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1

Boron Neutron Capture Therapy for Murine Malignant Gliomas  

Science Journals Connector (OSTI)

...September 1992 research-article Boron Neutron Capture Therapy for Murine Malignant Gliomas...Washington Street, Boston, MA 02111. Boron neutron capture therapy (BNCT) involves administration of a boron compound followed by neutron irradiation of the target organ. The...

Stephen C. Saris; Guido R. Solares; David E. Wazer; Guillermo Cano; Sarah E. Kerley; Melita A. Joyce; Lester S. Adelman; Otto K. Harling; Hywel Madoc-Jones; Robert G. Zamenhof

1992-09-01T23:59:59.000Z

2

A Critical Assessment of Boron Neutron Capture Therapy: An Overview  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when boron-10 is irradiated with neutrons of the appropriate...

Rolf F. Barth

2003-03-01T23:59:59.000Z

3

Pre-Clinical Studies on Boron Neutron Capture Therapy  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when boron-10 is irradiated with thermal neutrons to yield...1

Rolf F. Barth; Albert H. Soloway…

1989-01-01T23:59:59.000Z

4

Boron Neutron Capture Therapy of a Murine Melanoma  

Science Journals Connector (OSTI)

...glioblastoma multiforme treated by neutron capture therapy using boron-10. Cancer (Phila.), S: 601-615, 1955. 11. Asbury...of fourteen cases of malignant brain tumor treated by boron-10 slow neutron capture radiation. J. Neuropathol. Exp...

Jeffrey A. Coderre; John A. Kalef-Ezra; Ralph G. Fairchild; Peggy L. Micca; Lawrence E. Reinstein; John D. Glass

1988-11-15T23:59:59.000Z

5

Boron Neutron Capture Therapy of a Murine Melanoma  

Science Journals Connector (OSTI)

...research-article Basic Sciences Boron Neutron Capture Therapy of a Murine Melanoma 1...for reprints should be addressed. Boron neutron capture therapy has been carried out on...Irradiations with a predominantly thermal neutron beam were performed at the Brookhaven...

Jeffrey A. Coderre; John A. Kalef-Ezra; Ralph G. Fairchild; Peggy L. Micca; Lawrence E. Reinstein; John D. Glass

1988-11-15T23:59:59.000Z

6

Boron neutron capture therapy of primary and metastatic brain tumors  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when a stable isotope, boron-10, is irradiated with low energy (0....n th) to yield alpha (4He) particles and,7Li ...

Rolf F. Barth; Albert H. Soloway

7

Hypoxia-selective compounds for boron neutron capture therapy  

E-Print Network (OSTI)

Boron neutron capture therapy (BNCT) is a biochemically targeted form of radiotherapy for cancer. In BNCT, a compound labeled with the stable isotope boron-10 is systemically administered, and tumor cells selectively uptake ...

Shah, Jungal (Jugal Kaushik)

2008-01-01T23:59:59.000Z

8

Boron Neutron Capture Therapy of Intracerebral Melanoma Using Boronophenylalanine as a Capture Agent  

Science Journals Connector (OSTI)

...Kobayashi. T., and Kanda. K. Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radial...of fourteen cases of malignant brain tumors treated by boron-10 slow neutron capture radiation. J. Neuropalhol. & Exp...

Khalid Z. Matalka; Michael Q. Bailey; Rolf F. Barth; Alfred E. Staubus; Albert H. Soloway; Melvin L. Moeschberger; Jeffrey A. Coderre; Einar K. Rofstad

1993-07-15T23:59:59.000Z

9

Boron Neutron Capture Therapy of Intracerebral Melanoma Using Boronophenylalanine as a Capture Agent  

Science Journals Connector (OSTI)

...research-article Experimental Therapeutics Boron Neutron Capture Therapy of Intracerebral Melanoma...the Fourth International Symposium on Neutron Capture Therapy, Sydney, Australia...at the Fifth International Symposium on Neutron Therapy, Columbus, OH, September 13-17...

Khalid Z. Matalka; Michael Q. Bailey; Rolf F. Barth; Alfred E. Staubus; Albert H. Soloway; Melvin L. Moeschberger; Jeffrey A. Coderre; Einar K. Rofstad

1993-07-15T23:59:59.000Z

10

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1997-03-18T23:59:59.000Z

11

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

Miura, M.; Slatkin, D.N.

1997-03-18T23:59:59.000Z

12

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1995-10-03T23:59:59.000Z

13

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na{sub 4}B{sub 12}I{sub 11}SSB{sub 12}I{sub 11}, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy. 1 fig.

Miura, M.; Slatkin, D.N.

1997-08-05T23:59:59.000Z

14

Halogenated sulfidohydroboranes for nuclear medicine and boron neutron capture therapy  

DOE Patents (OSTI)

A method for performing boron neutron capture therapy for the treatment of tumors is disclosed. The method includes administering to a patient an iodinated sulfidohydroborane, a boron-10-containing compound. The site of the tumor is localized. by visualizing the increased concentration of the iodine labelled compound at the tumor. The targeted tumor is then irradiated with a beam of neutrons having an energy distribution effective for neutron capture. Destruction of the tumor occurs due to high LET particle irradiation of the tissue secondary to the incident neutrons being captured by the boron-10 nuclei. Iodinated sulfidohydroboranes are disclosed which are especially suitable for the method of the invention. In a preferred embodiment, a compound having the formula Na.sub.4 B.sub.12 I.sub.11 SSB.sub.12 I.sub.11, or another pharmaceutically acceptable salt of the compound, may be administered to a cancer patient for boron neutron capture therapy.

Miura, Michiko (Hampton Bays, NY); Slatkin, Daniel N. (Southold, NY)

1997-08-05T23:59:59.000Z

15

Boron thermal/epithermal neutron capture therapy  

SciTech Connect

The development of various particle beams for radiotherapy represents an attempt to improve dose distribution, and to provide high LET radiations which are less sensitive to ambient physical and radiobiological factors such as oxygen tension, cell cycle, and dose rate. In general, a compromise is necessary as effective RBE is reduced in order to spread the dose distribution over the anticipated tumor volume. The approach of delivering stable non-toxic isotopes to tumor, and then activating these atoms subsequently via an external radiation beam has mator advantages; problems associated with high uptake of these isotopes in competing cell pools are obviated, and the general tumor volume can be included in the treatment field of the activating beam. As long as the normal tissues supporting tumor show a low uptake of the isotope to be activated, and as long as the range of the reaction products is short, dose will be restricted to tumor, with a consequent high therapeutic ratio. Neutron Capture Therapy (NCT) is generally carried out by activating boron-10 with low energy neutrons. The range of the high LET, low OER particles from the /sup 10/B(n, ..cap alpha..)/sup 7/Li reaction is approx. 10..mu.., or one cell diameter, a situation that is optimal for cell killing. Significant advantages may be gained by using the NCT procedure in conjunction with improved tissue penetration provided with epithermal or filtered beams, and new compounds showing physiological binding to tumor.

Fairchild, R.G.

1982-01-01T23:59:59.000Z

16

Boron neutron capture enhancement of fast neutron radiotherapy  

Science Journals Connector (OSTI)

Clinical trials have revealed a therapeutic advantage for fast neutron radiation over conventional photon radiation for salivary gland cancer prostate cancer sarcoma and a subgroup of lung cancer. Conversely fast neutron treatment of high grade astrocytic brain tumors [glioblastoma multiforme (GBM)] resulted in tumor sterilization but also caused significant brain injury such that no therapeutic gain was attained. This effect was important however in that photon radiation and other conventional treatments have not demonstrated sterilization of GBM at any dose. Recent laboratory studies demonstrated that the hospital-based fast neutron beam from the University of Washington cyclotron has a thermal neutron component that may be used in a boron-10 neutron capture (BNC) reaction to enhance cell kill. The degree of enhancement was approximately 10 fold and was dependent upon the boron-10 concentration the boron-10 carrier agent and the fast neutron dose per fraction. The results of these experiments will be discussed in the context of creating a therapeutic window for treatment of glioblastoma using BNC-enhanced fast neutron radiation in a clinically tolerable regimen.

K. J. Stelzer; G. E. Laramore; R. Risler; L. Wiens; T. W. Griffin

1997-01-01T23:59:59.000Z

17

Radiobiological evaluation of new boron delivery agents for boron neutron capture therapy  

E-Print Network (OSTI)

This thesis evaluates the radiobiological effectiveness of three new boron compounds namely a boronated porphyrin (BOPP) and two liposome formulations for neutron capture therapy (BNCT). The methodology utilizes in vitro ...

Chung, Yoonsun

2008-01-01T23:59:59.000Z

18

BERAC Subcommittee Report on Boron Neutron Capture Therapy (BNCT) Clinical  

Office of Science (SC) Website

BERAC Subcommittee Report on Boron Neutron Capture BERAC Subcommittee Report on Boron Neutron Capture Therapy (BNCT) Clinical Trials. Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings Members Charges/Reports Current BERAC Charges Archive of BERAC Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Charges/Reports BERAC Subcommittee Report on Boron Neutron Capture Therapy (BNCT) Clinical Trials. Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Subcommittee Report on Boron Neutron Capture Therapy (BNCT) Clinical Trials. In response to the charge letter from Dr. Martha Krebs, Office of Science, dated November 5, 1998. Committee members: Bijay Mukherji, M.D., Chair, University of Connecticut Health Sciences Center, Walter Curran, M.D., Thomas Jefferson University;

19

Radiobiology of normal rat lung in Boron Neutron Capture Therapy  

E-Print Network (OSTI)

Boron Neutron Capture Therapy (BNCT) is a binary cancer radiation therapy that utilizes biochemical tumor cell targeting and provides a mixed field of high and low Linear Energy Transfer (LET) radiation with differing ...

Kiger, Jingli Liu

2006-01-01T23:59:59.000Z

20

Boron Neutron Capture Therapy for Murine Malignant Gliomas  

Science Journals Connector (OSTI)

...contamination from higher energy neutrons (fast and...performed with a General Electric 100-kV superficial...from the Department of Energy. The efforts of George...Sweet, W. H. Tissue distribution of boron compounds in...dosimetry and treatment planning for neutron capture...

Stephen C. Saris; Guido R. Solares; David E. Wazer; Guillermo Cano; Sarah E. Kerley; Melita A. Joyce; Lester S. Adelman; Otto K. Harling; Hywel Madoc-Jones; and Robert G. Zamenhof

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

A Novel Method of Boron Delivery Using Sodium Iodide Symporter for Boron Neutron Capture Therapy  

Science Journals Connector (OSTI)

......interact locally with sequestered boron, 10 B, in the target cells to produce...effectiveness of BNCT is how to concentrate boron-10 in cancer cells preferentially and...Bond VP (1980) Current status of boron-10- neutron capture therapy: enhancement......

Sanath Kumar; Svend O. Freytag; Kenneth N. Barton; Jay Burmeister; Michael C. Joiner; Bijan Sedghi; Benjamin Movsas; Peter J. Binns; Jae Ho Kim; Stephen L. Brown

2010-09-01T23:59:59.000Z

22

Boron containing compounds and their preparation and use in neutron capture therapy  

DOE Patents (OSTI)

The present invention pertains to boron containing thiouracil derivatives, their method of preparations, and their use in the therapy of malignant melanoma using boron neutron capture therapy.

Gabel, Detlef (Bremen, DE)

1992-01-01T23:59:59.000Z

23

Boron Neutron Capture Therapy for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model  

Science Journals Connector (OSTI)

Advances in Brief Boron Neutron Capture Therapy for the Treatment of...pouch model of oral cancer for boron neutron capture therapy (BNCT) studies and...irradiation with a thermal or epithermal neutron beam with tumor-seeking, boron-containing...

Erica L. Kreimann; Maria E. Itoiz; Juan Longhino; Herman Blaumann; Osvaldo Calzetta; Amanda E. Schwint

2001-12-15T23:59:59.000Z

24

A revised boron-neutron capture therapy for malignant brain tumours  

Science Journals Connector (OSTI)

Boron-Neutron Capture Therapy based on the nuclear reaction between low energy neutron and non-radioactive isotope Boron-10 which produces short-range alpha-particle has...

Hiroshi Hatanaka; Keiji Sano

25

Carborane derivative development for boron neutron capture therapy. Final report  

SciTech Connect

Boron Neutron Capture Therapy [BNCT] is a binary method of cancer therapy based on the capture of neutrons by a boron-10 atom [{sup 10}B]. Cytotoxic {sup 7}Li nuclei and {alpha}-particles are emitted, with a range in tissue of 9 and 5 {micro}m, respectively, about one cell diameter. The major obstacle to clinically viable BNCT is the selective localization of 5-30 ppm {sup 10}B in tumor cells required for effective therapy. A promising approach to BNCT is based on hydrophilic boron-rich oligomeric phosphate diesters, or ''trailers'' that have been shown to concentrate selectively in tumor tissue. Examples of these compounds were prepared previously at high cost using an automated DNA synthesizer. Direct synthesis methods are needed for the production of gram-scale quantities for further biological evaluation. The work accomplished as a result of the collaboration between Fluorochem, Inc. and UCLA demonstrates that short oligomers containing at least five carborane units with four phosphodiester linkages can be prepared in substantial quantities. This work was accomplished by the application of standard phosphoramidite coupling chemistry.

Barnum, Beverly A.; Yan Hao; Moore, Roger; Hawthorne, M. Frederick; Baum, Kurt

1999-04-01T23:59:59.000Z

26

Boron Neutron Capture Therapy of Cancer: Current Status and Future Prospects  

Science Journals Connector (OSTI)

...for Cancer Research Review Reviews Boron Neutron Capture Therapy of Cancer: Current Status...indicate this fact. Background: Boron neutron capture therapy (BNCT) is based on the...is irradiated with low-energy thermal neutrons to yield high linear energy transfer alpha...

Rolf F. Barth; Jeffrey A. Coderre; M. Graça H. Vicente; Thomas E. Blue

2005-06-01T23:59:59.000Z

27

Boron Analytical Studies on 10B1-BPA Administration for Neutron Capture Therapy of Malignant Melanoma  

Science Journals Connector (OSTI)

Success of boron neutron capture therapy (NCT) for cancer depends mainly upon selective boron accumulation in the targeted tumor. Since 1987 we have succeeded in treating human melanoma lesions by NCT utilizing10

C. Honda; N. Wadabayashi; K. Yoshino; J. Hiratsuka…

1996-01-01T23:59:59.000Z

28

Development of a gamma ray telescope for online synovial dosimetry in boron neutron capture synovectomy  

E-Print Network (OSTI)

Boron Neutron Capture Synovectomy (BNCS) is a novel application of the ¹?B(n,?) reaction for potential treatment of rheumatoid arthritis. During BNCS clinical trials, real-time knowledge of boron dose delivered to the ...

Jiang, Hongyu, 1971-

2003-01-01T23:59:59.000Z

29

A PC-Based Computer Program for the Estimation of the Radiation Dose in in Vitro and in Vivo Boron Neutron Capture Irradiation Experiments  

Science Journals Connector (OSTI)

In Boron Neutron Capture Therapy (BNCT) microdosimetry of charged particle radiation depends on total boron concentration and intracellular boron distribution. Due to the inhomogeneity of boron distribution in...

Ruud Verrijk; Rene Huiskamp; Adrian C. Begg

1993-01-01T23:59:59.000Z

30

Boron Neutron Capture Therapy for Murine Malignant Gliomas  

Science Journals Connector (OSTI)

...and epithermal neutron component comprised approximately 5% of the total dose; the majority (~80%) came from the boron-10 reaction and the rest from photons and thermal neutrons (data not shown). All subsequently described BNCT doses are...

Stephen C. Saris; Guido R. Solares; David E. Wazer; Guillermo Cano; Sarah E. Kerley; Melita A. Joyce; Lester S. Adelman; Otto K. Harling; Hywel Madoc-Jones; Robert G. Zamenhof

1992-09-01T23:59:59.000Z

31

Estimation of relative biological effectiveness for boron neutron capture therapy using the PHITS code coupled with a microdosimetric kinetic model  

Science Journals Connector (OSTI)

......Soloway AH, Goodman JH, et al. Boron neutron capture therapy of brain tumors: an emerging therapeutic modality. Neurosurgery (1999...distribution for intraoperative boron neutron capture therapy of brain tumours. Phys Med Biol (2002) 47:2387-96. 27 Nguyen......

Hironori Horiguchi; Tatsuhiko Sato; Hiroaki Kumada; Tetsuya Yamamoto; Takeji Sakae

2014-11-01T23:59:59.000Z

32

Boron Neutron Capture Therapy of Cancer: Current Status and Future Prospects  

Science Journals Connector (OSTI)

...nuclear reaction that occurs when boron-10 is irradiated with low-energy thermal...fission reactions that occur when boron-10 (10B), which is a nonradioactive...by neutron-capture therapy using boron 10. Cancer 1955;8:601-15. 36...

Rolf F. Barth; Jeffrey A. Coderre; M. Graça H. Vicente; Thomas E. Blue

2005-06-01T23:59:59.000Z

33

Treatment Planning for Accelerator-Based Boron Neutron Capture Therapy  

SciTech Connect

Glioblastoma multiforme and metastatic melanoma are frequent brain tumors in adults and presently still incurable diseases. Boron Neutron Capture Therapy (BNCT) is a promising alternative for this kind of pathologies. Accelerators have been proposed for BNCT as a way to circumvent the problem of siting reactors in hospitals and for their relative simplicity and lower cost among other advantages. Considerable effort is going into the development of accelerator-based BNCT neutron sources in Argentina. Epithermal neutron beams will be produced through appropriate proton-induced nuclear reactions and optimized beam shaping assemblies. Using these sources, computational dose distributions were evaluated in a real patient with diagnosed glioblastoma treated with BNCT. The simulated irradiation was delivered in order to optimize dose to the tumors within the normal tissue constraints. Using Monte Carlo radiation transport calculations, dose distributions were generated for brain, skin and tumor. Also, the dosimetry was studied by computing cumulative dose-volume histograms for volumes of interest. The results suggest acceptable skin average dose and a significant dose delivered to tumor with low average whole brain dose for irradiation times less than 60 minutes, indicating a good performance of an accelerator-based BNCT treatment.

Herrera, Maria S.; Gonzalez, Sara J. [Comision National de Energia Atomica and CONICET, Buenos Aires (Argentina); Minsky, Daniel M.; Kreiner, Andres J. [Comision National de Energia Atomica and CONICET, Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, UNSAM, Buenos Aires (Argentina)

2010-08-04T23:59:59.000Z

34

Abstract 738: Re-irradiation for recurrent malignant glioma by boron neutron capture therapy  

Science Journals Connector (OSTI)

...OBJECTIVE: Boron neutron capture therapy (BNCT) is based upon the nuclear reaction that occur when non-radioactive boron-10 (10B) is irradiated with low energy neutrons to produce high energy a particles (10B[n, alpha] 7Li). In order...

Shinji Kawabata; Shin-Ichi Miyatake; Ryo Hiramatsu; Toshihiko Kuroiwa; Koji Ono

2012-06-04T23:59:59.000Z

35

Design and construction of an optimized neutron beam shaping assembly for Boron Neutron Capture Therapy at the Tandar accelerator  

SciTech Connect

In this work we present an optimized neutron beam shaping assembly for epithermal Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) and discuss the simulations leading to its design.

Burlon, A. [Universidad de Gral San Martin (Argentina); Comision Nacional de Energia Atomica, (Argentina); Fundacion Sauberan (Argentina); Kreiner, A. J. [Universidad de Gral San Martin (Argentina); Comision Nacional de Energia Atomica (Argentina); CONICET (Argentina); Valda, A. A.; Somacal, H. [Universidad de Gral San Martin (Argentina); Minsky, D. M. [Comision Nacional de Energia Atomica (Argentina); Universidad de Gral San Martin (Argentina)

2007-02-12T23:59:59.000Z

36

Boron Neutron Capture Therapy of Brain Tumors: Enhanced Survival following Intracarotid Injection of either Sodium Borocaptate or Boronophenylalanine with or without Blood-Brain Barrier Disruption  

Science Journals Connector (OSTI)

...research-article Experimental Therapeutics Boron Neutron Capture Therapy of Brain Tumors: Enhanced...the Seventh International Symposium on Neutron Capture Therapy, Zurich, Switzerland...determine whether the efficacy of boron neutron capture therapy could be enhanced by means...

Rolf F. Barth; Weilian Yang; Joan H. Rotaru; Melvin L. Moeschberger; Darrel D. Joel; Marta M. Nawrocky; Joseph H. Goodman; Albert H. Soloway

1997-03-15T23:59:59.000Z

37

Design of a boron neutron capture enhanced fast neutron therapy assembly  

SciTech Connect

The use of boron neutron capture to boost tumor dose in fast neutron therapy has been investigated at several fast neutron therapy centers worldwide. This treatment is termed boron neutron capture enhanced fast neutron therapy (BNCEFNT). It is a combination of boron neutron capture therapy (BNCT) and fast neutron therapy (FNT). It is believed that BNCEFNT may be useful in the treatment of some radioresistant brain tumors, such as glioblastoma multiform (GBM). A boron neutron capture enhanced fast neutron therapy assembly has been designed for the Fermilab Neutron Therapy Facility (NTF). This assembly uses a tungsten filter and collimator near the patient's head, with a graphite reflector surrounding the head to significantly increase the dose due to boron neutron capture reactions. The assembly was designed using Monte Carlo radiation transport code MCNP version 5 for a standard 20x20 cm{sup 2} treatment beam. The calculated boron dose enhancement at 5.7-cm depth in a water-filled head phantom in the assembly with a 5x5 cm{sup 2} collimation was 21.9% per 100-ppm {sup 10}B for a 5.0-cm tungsten filter and 29.8% for a 8.5-cm tungsten filter. The corresponding dose rate for the 5.0-cm and 8.5-cm thick filters were 0.221 and 0.127 Gy/min, respectively; about 48.5% and 27.9% of the dose rate of the standard 10x10 cm{sup 2} fast neutron treatment beam. To validate the design calculations, a simplified BNCEFNT assembly was built using four lead bricks to form a 5x5 cm{sup 2} collimator. Five 1.0-cm thick 20x20 cm{sup 2} tungsten plates were used to obtain different filter thicknesses and graphite bricks/blocks were used to form a reflector. Measurements of the dose enhancement of the simplified assembly in a water-filled head phantom were performed using a pair of tissue-equivalent ion chambers. One of the ion chambers is loaded with 1000-ppm natural boron (184-ppm {sup 10}B) to measure dose due to boron neutron capture. The measured dose enhancement at 5.0-cm depth in the head phantom for the 5.0-cm thick tungsten filter is (16.6 {+-} 1.8)%, which agrees well with the MCNP simulation of the simplified BNCEFNT assembly, (16.4 {+-} 0.5)%. The error in the calculated dose enhancement only considers the statistical uncertainties. The total dose rate measured at 5.0-cm depth using the non-borated ion chamber is (0.765 {+-} 0.076) Gy/MU, about 61% of the fast neutron standard dose rate (1.255Gy/MU) at 5.0-cm depth for the standard 10x10 cm{sup 2} treatment beam. The increased doses to other organs due to the use of the BNCEFNT assembly were calculated using MCNP5 and a MIRD phantom. The activities of the activation products produced in the BNCEFNT assembly after neutron beam delivery were computed. The photon ambient dose rate due to the radioactive activation products was also estimated.

Wang, Zhonglu; /Georgia Tech; ,

2006-08-01T23:59:59.000Z

38

Relation Between Tolerance Dose of Skin and Boron-10 Concentration in Neutron Capture Therapy for Cutaneous Melanoma  

Science Journals Connector (OSTI)

In boron neutron capture therapy of cutaneous melanoma1, damage to scalp, facial skin and eyes must be strictly avoided. Two basic irradiation conditions follow: (1) ...

Tooru Kobayashi; Keiji Kanda; Yowri Ujeno…

1992-01-01T23:59:59.000Z

39

Dosimetry and spectrometry at accelerator based neutron source for boron neutron capture therapy  

Science Journals Connector (OSTI)

An innovative accelerator-based neutron source for boron neutron capture therapy has started operation at the Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10 mA. Epithermal neutrons are proposed to be generated by 1.915 MeV protons bombarding a lithium target using 7Li(p,n)7Be threshold reaction. In the article, techniques to detect neutron and gamma-rays at the facility are described. Gamma radiation is measured with NaI and BGO gamma-spectrometers. The total yield of neutrons is determined by measuring the 477 keV ?-quanta from beryllium decay. For the rough analysis of the generated neutron spectrum we used bubble detectors. As the epithermal neutrons are of interest for neutron capture therapy the NaI detector is used as activation detector. We plan to use a time-of-flight technique for neutron spectra measurement. To realize this technique a new solution of short time neutron generation is proposed.

B. Bayanov; A. Burdakov; A. Kuznetsov; A. Makarov; S. Sinitskii; Yu. Sulyaev; S. Taskaev

2010-01-01T23:59:59.000Z

40

The mapping of natural boron in histological sections of mouse tissues by the use of neutron-capture radiography  

Science Journals Connector (OSTI)

Neutron-capture radiography has been applied to the mapping of natural boron in mouse histological sections. The method is based on the fact that the stable isotope boron-10 has an extremely large cross-section f...

Maria Laurent-Pettersson; Bertrand Delpech; Michel Thellier

1992-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Boron Neutron Capture Therapy (BNCT) Dose Calculation using Geometrical Factors Spherical Interface for Glioblastoma Multiforme  

SciTech Connect

Boron Neutron Capture Therapy (BNCT) is a cancer therapy by utilizing thermal neutron to produce alpha particles and lithium nuclei. The superiority of BNCT is that the radiation effects could be limited only for the tumor cells. BNCT radiation dose depends on the distribution of boron in the tumor. Absorbed dose to the cells from the reaction 10B (n, {alpha}) 7Li was calculated near interface medium containing boron and boron-free region. The method considers the contribution of the alpha particle and recoiled lithium particle to the absorbed dose and the variation of Linear Energy Transfer (LET) charged particles energy. Geometrical factor data of boron distribution for the spherical surface is used to calculate the energy absorbed in the tumor cells, brain and scalp for case Glioblastoma Multiforme. The result shows that the optimal dose in tumor is obtained for boron concentrations of 22.1 mg {sup 10}B/g blood.

Zasneda, Sabriani; Widita, Rena [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10 Bandung, 40132 (Indonesia)

2010-06-22T23:59:59.000Z

42

Nuclear Physics meets Medicine and Biology: Boron Neutron Capture Therapy  

E-Print Network (OSTI)

BNCT is a tumour treatment based on thermal-neutron irradiation of tissues enriched with 10B, which according to the 10B(n, )7Li reaction produces particles with high Linear Energy Transfer and short range. Since this treatment can deliver a therapeutic tumour dose sparing normal tissues, BNCT represents an alternative for diffuse tumours and metastases, which show poor response to surgery and photontherapy. In 2001 and 2003, in Pavia BNCT was applied to an isolated liver, which was infused with boron, explanted, irradiated and re-implanted. A new project was then initiated for lung tumours, developing a protocol for Boron concentration measurements and performing organ-dose Monte Carlo calculations; in parallel, radiobiology studies are ongoing to characterize the BNCT effects down to cellular level. After a brief introduction, herein we will present the main activities ongoing in Pavia including the radiobiological ones, which are under investigation not only experimentally but also theoretically, basing on...

F. Ballarini, F; S. Bortolussi, S; P. Bruschi, P; A.M. Clerici, A M; A. De Bari, A; P. Dionigi, P; C. Ferrari, C; M.A. Gadan, M A; N. Protti, N; S. Stella, S; C. Zonta, C; A. Zonta, A; S. Altieri, S

2010-01-01T23:59:59.000Z

43

Accelerator-based neutron source for boron neutron capture therapy (BNCT) and method  

DOE Patents (OSTI)

A source for boron neutron capture therapy (BNCT) comprises a body of photoneutron emitter that includes heavy water and is closely surrounded in heat-imparting relationship by target material; one or more electron linear accelerators for supplying electron radiation having energy of substantially 2 to 10 MeV and for impinging such radiation on the target material, whereby photoneutrons are produced and heat is absorbed from the target material by the body of photoneutron emitter. The heavy water is circulated through a cooling arrangement to remove heat. A tank, desirably cylindrical or spherical, contains the heavy water, and a desired number of the electron accelerators circumferentially surround the tank and the target material as preferably made up of thin plates of metallic tungsten. Neutrons generated within the tank are passed through a surrounding region containing neutron filtering and moderating materials and through neutron delimiting structure to produce a beam or beams of epithermal neutrons normally having a minimum flux intensity level of 1.0.times.10.sup.9 neutrons per square centimeter per second. Such beam or beams of epithermal neutrons are passed through gamma ray attenuating material to provide the required epithermal neutrons for BNCT use.

Yoon, Woo Y. (Idaho Falls, ID); Jones, James L. (Idaho Falls, ID); Nigg, David W. (Idaho Falls, ID); Harker, Yale D. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

44

Accelerator-based neutron source for boron neutron capture therapy (BNCT) and method  

DOE Patents (OSTI)

A source for boron neutron capture therapy (BNCT) comprises a body of photoneutron emitter that includes heavy water and is closely surrounded in heat-imparting relationship by target material; one or more electron linear accelerators for supplying electron radiation having energy of substantially 2 to 10 MeV and for impinging such radiation on the target material, whereby photoneutrons are produced and heat is absorbed from the target material by the body of photoneutron emitter. The heavy water is circulated through a cooling arrangement to remove heat. A tank, desirably cylindrical or spherical, contains the heavy water, and a desired number of the electron accelerators circumferentially surround the tank and the target material as preferably made up of thin plates of metallic tungsten. Neutrons generated within the tank are passed through a surrounding region containing neutron filtering and moderating materials and through neutron delimiting structure to produce a beam or beams of epithermal neutrons normally having a minimum flux intensity level of 1.0{times}10{sup 9} neutrons per square centimeter per second. Such beam or beams of epithermal neutrons are passed through gamma ray attenuating material to provide the required epithermal neutrons for BNCT use. 3 figs.

Yoon, W.Y.; Jones, J.L.; Nigg, D.W.; Harker, Y.D.

1999-05-11T23:59:59.000Z

45

Tomographic image of prompt gamma ray from boron neutron capture therapy: A Monte Carlo simulation study  

SciTech Connect

Purpose of paper is to confirm the feasibility of acquisition of three dimensional single photon emission computed tomography image from boron neutron capture therapy using Monte Carlo simulation. Prompt gamma ray (478?keV) was used to reconstruct image with ordered subsets expectation maximization method. From analysis of receiver operating characteristic curve, area under curve values of three boron regions were 0.738, 0.623, and 0.817. The differences between length of centers of two boron regions and distance of maximum count points were 0.3?cm, 1.6?cm, and 1.4?cm.

Yoon, Do-Kun; Jung, Joo-Young; Suk Suh, Tae, E-mail: suhsanta@catholic.ac.kr [Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul 505 (Korea, Republic of); Jo Hong, Key [Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, 300 Pasteur Drive, Stanford, California 94305 (United States)

2014-02-24T23:59:59.000Z

46

Boron Neutron Capture Therapy for Newly Diagnosed Glioblastoma  

Science Journals Connector (OSTI)

......particle radiation, comprises a binary approach. First, a boron-10 (10 B)-labeled compound delivers high concentrations...2001) Quantitative imaging and microlo- calization of boron-10 in brain tumors and infiltrating tumor cells by SIMS ion......

Shinji Kawabata; Shin-Ichi Miyatake; Toshihiko Kuroiwa; Kunio Yokoyama; Atsushi Doi; Kyoko Iida; Shiro Miyata; Naosuke Nonoguchi; Hiroyuki Michiue; Masatsugu Takahashi; Taisuke Inomata; Yoshio Imahori; Mitsunori Kirihata; Yoshinori Sakurai; Akira Maruhashi; Hiroaki Kumada; Koji Ono

2009-01-01T23:59:59.000Z

47

Numerical characterization of a tomographic system for online dose measurements in Boron Neutron Capture Therapy  

SciTech Connect

A tomographic system for online dose measurements in Boron Neutron Capture Therapy (BNCT) based on the measurement of a specific 478 keV {gamma}-ray emitted after the neutron capture in boron is being developed. In the present work we study by means of Monte Carlo numerical simulations the effects of the finite spatial resolution and the limited number of counts, i. e. the statistical noise, on the reconstructed image contrast of numerical phantoms. These phantoms, of simple geometry, mimic the tumor (specific) and the normal tissue (non specific) boron concentrations. The simulated projection data were reconstructed using the expectation-maximization maximum-likelihood algorithm. These studies will help in the improvement of BNCT dosimetry.

Minsky, D. M.; Valda, A. A.; Somacal, H. [Escuela de Ciencia y Tecnologia (UNSAM), San Martin, Buenos Aires (Argentina); Dpto. de Fisica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Burlon, A. A. [Escuela de Ciencia y Tecnologia (UNSAM), San Martin, Buenos Aires (Argentina); Dpto. de Fisica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Fundacion J.B. Sauberan (Argentina); Kreiner, A. J. [Escuela de Ciencia y Tecnologia (UNSAM), San Martin, Buenos Aires (Argentina); Dpto. de Fisica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); CONICET (Argentina)

2007-02-12T23:59:59.000Z

48

Boron Neutron Capture Therapy (BCNT) for the Treatment of Liver Metastases: Biodistribution Studies of Boron Compounds in an Experimental Model  

SciTech Connect

Abstract We previously demonstrated the therapeutic efficacy of different boron neutron capture therapy (BNCT) protocols in an experimental model of oral cancer. BNCT is based on the selective accumulation of 10B carriers in a tumor followed by neutron irradiation. Within the context of exploring the potential therapeutic efficacy of BNCT for the treatment of liver metastases, the aim of the present study was to perform boron biodistribution studies in an experimental model of liver metastases in rats. Different boron compounds and administration conditions were assayed to determine which administration protocols would potentially be therapeutically useful in in vivo BNCT studies at the RA-3 nuclear reactor. A total of 70 BDIX rats were inoculated in the liver with syngeneic colon cancer cells DHD/K12/TRb to induce the development of subcapsular tumor nodules. Fourteen days post-inoculation, the animals were used for biodistribution studies. We evaluated a total of 11 administration protocols for the boron compounds boronophenylalanine (BPA) and GB-10 (Na210B10H10), alone or combined at different dose levels and employing different administration routes. Tumor, normal tissue, and blood samples were processed for boron measurement by atomic emission spectroscopy. Six protocols proved potentially useful for BNCT studies in terms of absolute boron concentration in tumor and preferential uptake of boron by tumor tissue. Boron concentration values in tumor and normal tissues in the liver metastases model show it would be feasible to reach therapeutic BNCT doses in tumor without exceeding radiotolerance in normal tissue at the thermal neutron facility at RA-3.

Marcela A. Garabalino; Andrea Monti Hughes; Ana J. Molinari; Elisa M. Heber; Emiliano C. C. Pozzi; Maria E. Itoiz; Veronica A. Trivillin; Amanda E. Schwint; Jorge E. Cardoso; Lucas L. Colombo; Susana Nievas; David W. Nigg; Romina F. Aromando

2011-03-01T23:59:59.000Z

49

Neutron-capture therapy of human cancer: in vivo results on tumor localization of boron-10-labeled antibodies to carcinoembryonic antigen in the GW-39 tumor model system  

Science Journals Connector (OSTI)

...results on tumor localization of boron-10-labeled antibodies to carcinoembryonic...their suitability for transporting boron-10 to tumors for use in neutron-capture...results on tumor localization of boron-10-labeled antibodies to carcinoembryonic...

D M Goldenberg; R M Sharkey; F J Primus; E Mizusawa; M F Hawthorne

1984-01-01T23:59:59.000Z

50

>18F-labeled BPA positron emmision tomography (PET) based Boron Neutron Capture Therapy on malignant glioma patients in Japan  

Science Journals Connector (OSTI)

...2006] B79 Boron neutron capture therapy (BNCT) is based upon the nuclear reaction that occur when non-radioactive boron-10 (10B) is irradiated with low energy neutrons to produce high energy a particles (10B[n,alpha] 7Li). In order...

Shinji Kawabata; Shin-Ichi Miyatake; Minoru Miyashita; Atsushi Doi; Kyouko Iida; Toshihiko Kuroiwa; Yoshio Imahori; Koji Ono

2006-10-01T23:59:59.000Z

51

Combination radiotherapy with boron neutron capture therapy and external beam X-tay irradiation for malignant glioma -our new protocol  

Science Journals Connector (OSTI)

...CA 5061 Boron neutron capture therapy (BNCT) is based upon the nuclear reaction that occur when non-radioactive boron-10 (10B) is irradiated with low energy neutrons to produce high energy a particles (10B[n,alpha] 7Li). In order...

Shinji Kawabata; Shin-Ichi Miyatake; Kyoko Iida; Atsushi Doi; Yoshinaga Kajimoto; Toshihiko Kuroiwa; Koji Ono

2007-05-01T23:59:59.000Z

52

Ion Microscopy Imaging of 10B from p-Boronophenylalanine in a Brain Tumor Model for Boron Neutron Capture Therapy  

Science Journals Connector (OSTI)

...prospects. Cancer (Phila.). 70: 2995-3007, 1992. Kobayashi, T., and Kanda. K. Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radi t.Res.. 91: 77-94. 1982. Gabel. D., Foster, S...

Duane R. Smith; Subhash Chandra; Jeffrey A. Coderre; George H. Morrison

1996-10-01T23:59:59.000Z

53

Chemistry and biology of some low molecular weight boron compounds for Boron Neutron Capture Therapy  

Science Journals Connector (OSTI)

Boronated DNA targeting agents are especially attractive candidatesfor BNCT because they may deliver boron-10 tothe nuclei of tumor cells. Numerous boron...

Stefan Sjöberg; Jörgen Carlsson; Hadi Ghaneolhosseini…

1997-05-01T23:59:59.000Z

54

Boron neutron capture therapy for oral precancer: proof of principle in an experimental animal model  

SciTech Connect

Field-cancerized tissue can give rise to second primary tumours, causing therapeutic failure. Boron neutron capture therapy (BNCT) is based on biological targeting and would serve to treat undetectable foci of malignant transformation. The aim of this study was to optimize BNCT for the integral treatment for oral cancer, with particular emphasis on the inhibitory effect on tumour development originating in precancerous conditions, and radiotoxicity of different BNCT protocols in a hamster cheek pouch oral precancer model.

A. Monti Hughes; ECC Pozzi; S. Thorp; M. A. Garabalino; R. O. Farias; S. J. Gonzalez; E. M. Heber; M. E. Itoiz; R. F. Aromando; A. J. Molinari; M. Miller; D. W. Nigg; P. Curotto; V. A. Trivillin; A. E. Schwint

2013-11-01T23:59:59.000Z

55

Dose point kernel for boron-11 decay and the cellular S values in boron neutron capture therapy  

Science Journals Connector (OSTI)

The study of the radiobiology of boronneutron capture therapy is based on the cellular level dosimetry of boron-10’s thermal neutron capture reaction B 10 ( n ? ) Li 7 in which one 1.47 MeV helium-4 ion and one 0.84 MeV lithium-7 ion are spawned. Because of the chemical preference of boron-10 carrier molecules the dose is heterogeneously distributed in cells. In the present work the (scaled) dose point kernel of boron-11 decay called B 11 -DPK was calculated by GEANT4Monte Carlo simulation code. The DPK curve drops suddenly at the radius of 4.26 ? m the continuous slowing down approximation (CSDA) range of a lithium-7 ion. Then after a slight ascending the curve decreases to near zero when the radius goes beyond 8.20 ? m which is the CSDA range of a 1.47 MeV helium-4 ion. With the DPK data S values for nuclei and cells with the boron-10 on the cell surface are calculated for different combinations of cell and nucleus sizes. The S value for a cell radius of 10 ? m and a nucleus radius of 5 ? m is slightly larger than the value published by Tung et al. [Appl. Radiat. Isot.61 739–743 (2004)]. This result is potentially more accurate than the published value since it includes the contribution of a lithium-7 ion as well as the alpha particle.

Yunzhi Ma; JinPeng Geng; Song Gao; Shanglian Bao

2006-01-01T23:59:59.000Z

56

Tandem-ESQ for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT)  

SciTech Connect

A folded tandem, with 1.25 MV terminal voltage, combined with an ElectroStatic Quadrupole (ESQ) chain is being proposed as a machine for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT). The machine is shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the on the 7Li(p,n)7Be reaction, to perform BNCT treatment for deep seated tumors in less than an hour.

Kreiner, A. J. [Departamento de Fisica, Comision Nacional de Energia Atomica (Argentina); Escuela de Ciencia y Tecnologia, Universidad de Gral San Martin (Argentina); CONICET, (Argentina); Kwan, J. W.; Henestroza, E. [Ernest Orlando Lawrence Berkeley National Laboratory, Univ. of California, Berkeley, CA (United States); Burlon, A. A.; Di Paolo, H.; Minsky, D.; Debray, M. [Departamento de Fisica, Comision Nacional de Energia Atomica, (Argentina); Escuela de Ciencia y Tecnologia, Universidad de Gral San Martin (Argentina); Valda, A.; Somacal, H. R. [Escuela de Ciencia y Tecnologia, Universidad de Gral San Martin (Argentina)

2007-02-12T23:59:59.000Z

57

Neutron Capture Therapy  

Science Journals Connector (OSTI)

... . Only those elements which have a high thermal-neutron capture cross-section, such as boron-10, lithium-6, and uranium-235, are useful. This suggestion was first put forward ... was first put forward in 1936 by Locher. The utilization of thermal neutron capture by boron-10 for the treatment of human-brain tumours, chiefly glioblastoma multiforme, has been under investigation ...

1961-09-23T23:59:59.000Z

58

Nuclear magnetic resonance study of Gd-based nanoparticles to tag boron compounds in boron neutron capture therapy  

SciTech Connect

We report the investigation of new organic complexes containing a magnetic moment (Gd-based molecular nanomagnets), which can serve the double purpose of acting as boron neutron capture therapy (BNCT) agents, and at the same time act as contrast agents to detect the molecule in the tissue by a proton magnetic resonance imaging (MRI). We also explore the possibility of monitoring the concentration of the BNCT agent directly via proton and boron NMR relaxation. The absorption of {sup 10}B-enriched molecules inside tumoral liver tissues has been shown by NMR measurements and confirmed by {alpha} spectroscopy. A new molecular Gd-tagged nanomagnet and BNCT agent (GdBPA) has been synthesized and characterized measuring its relaxivity R{sub 1} between 10 kHz and 66 MHz, and its use as a contrast agent in MRI has been demonstrated. The NMR-based evidence of the absorption of GdBPA into living tumoral cells is also shown.

Corti, M.; Bonora, M.; Borsa, F. [Dipartimento di Fisica A.Volta, Unita CNISM e Unita INSTM, Via Bassi 6, Universita di Pavia, I-27100 Pavia (Italy); Bortolussi, S.; Protti, N.; Santoro, D.; Stella, S.; Altieri, S. [Dipartimento di Fisica Nucleare e Teorica e INFN Pavia, Via Bassi 6, Universita di Pavia, I-27100 Pavia (Italy); Zonta, C.; Clerici, A. M.; Cansolino, L.; Ferrari, C.; Dionigi, P. [Dipartimento di Scienze Chirurgiche, Laboratorio di Chirurgia Sperimentale Botta2, Via Ferrata 9, Universita di Pavia, I-27100 Pavia (Italy); Porta, A.; Zanoni, G.; Vidari, G. [Dipartimento di Chimica Organica, Via Taramelli 10, Universita di Pavia, I-27100 Pavia (Italy)

2011-04-01T23:59:59.000Z

59

Boron-Containing Nucleosides as Potential Delivery Agents for Neutron Capture Therapy of Brain Tumors  

Science Journals Connector (OSTI)

...capture reaction that occurs when boron-10, which is a non-radioactive constituent...sufficient amount (20 mug/g tumor) of boron-10 to sustain a 10B(n,a)7Li capture...fields. Subcellular Localization of Boron-10 by Means of Secondary Ion Mass Spectrometry...

Rolf F. Barth; Weilian Yang; Ashraf S. Al-Madhoun; Jayaseharan Johnsamuel; Youngjoo Byun; Subhash Chandra; Duane R. Smith; Werner Tjarks; Staffan Eriksson

2004-09-01T23:59:59.000Z

60

Intercomparison of inductively coupled plasma mass spectrometry, quantitative neutron capture radiography, and prompt gamma activation analysis for the determination of boron in biological samples  

Science Journals Connector (OSTI)

Boron determination is of special interest for the analysis of biological samples in the context of boron neutron capture therapy (BNCT). BNCT is ... . This is achieved by enrichment of the isotope 10B in tumour ...

C. L. Schütz; C. Brochhausen; G. Hampel…

2012-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Properties of a Cold-Neutron Irradiation Facility for In Vitro Research on Boron Neutron Capture Therapy at the Geesthacht Neutron Facility  

SciTech Connect

A new irradiation facility, GBET (basic research on boron neutron capture therapy), especially designed for in vitro experiments on boron neutron capture therapy was put into operation at the Geesthacht Neutron Facility of the GKSS Research Center. Its location at a cold-neutron guide without direct view of the reactor core has two advantages: First, contamination of the primary beam with fast neutrons or photons is negligible. Second, GBET yields a high cold-neutron flux of 1.4 x 10{sup 8}/(cm{sup 2}.s) over an area of 3 x 4 cm. As a result of the energy dependence of the neutron absorption cross section of boron, this corresponds to a higher effective thermal flux of 4.7 x 10{sup 8}/(cm{sup 2}.s). This effect is used to reduce the irradiation times by a factor of 3.32.The effective flux is sufficient for irradiation of thin samples like cell monolayers in conventional culture flasks. For such in vitro irradiations, a survival fraction of 1% is achieved at a homogeneous boron concentration of 100 ppm {sup 10}B within {approx}20 min. Furthermore, the beam can be used for boron radiography. The respective experimental conditions are discussed, especially the neutron flux distribution, available for these different types of samples.

Luedemann, L. [Institut fur Werkstofforschung, GKSS-Forschungszentrum Geesthacht (Germany); Kampmann, R. [Institut fur Werkstofforschung, GKSS-Forschungszentrum Geesthacht (Germany); Sosaat, W. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Staron, P. [Institut fur Werkstofforschung, GKSS-Forschungszentrum Geesthacht (Germany); Wille, P. [Institut fur Werkstofforschung, GKSS-Forschungszentrum Geesthacht (Germany)

2000-05-15T23:59:59.000Z

62

In Vitro Determination of Uptake, Retention, Distribution, Biological Efficacy, and Toxicity of Boronated Compounds for Neutron Capture Therapy: A Comparison of Porphyrins with Sulfhydryl Boron Hydrides  

Science Journals Connector (OSTI)

...capture therapy. Radi t.Res., ///: 14-25, 1987. 2. Kobayashi, T., and Kanda. K. Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radi t.Res., 91: 77-94, 1982. 3. Fairchild, R. C...

R. G. Fairchild; S. B. Kahl; B. H. Laster; J. Kalef-Ezra; E. A. Popenoe

1990-08-15T23:59:59.000Z

63

Microdosimetric considerations in the use of the boron neutron capture reaction in radiation therapy  

Science Journals Connector (OSTI)

This thesis attempts to further the understanding of the dosimetric and microdosimetric aspects of the boronneutron capture reaction (BNCR) in two distinct radiation therapy modalities the conventional BNCT and boronneutron capture enhanced fast neutron therapy (BNCEFNT). The absorbed dose in these two modalities consists of contributions from gamma rays neutrons and the neutron capture reactions in tissue including the BNCR. The use of low pressure tissue equivalent proportional counters for the dual purpose of dosimetry and microdosimetry of the complex radiation fields used in BNCT and BNCEFNT has been thoroughly investigated. Commercially obtained paired 1/2? Rossi type LET counters (with and without boron-10 in the A-150 TEP wall) were used in this work. The counters were dose calibrated by positioning the proton edge in the measured spectra at a lineal energy of 150 keV/micrometer. Using this paired counter technique the gamma neutron and BNCR dose components in different radiation fields were resolved. Experimental results indicate that this technique is well suited for the dosimetry of BNCT and BNCEFNT fields. The uncertainties in these dose measurements are smaller than or comparable to those achieved using conventional techniques. The microdosimetric spectra measured by the proportional counters have been found to be useful for evaluating the quality of these radiation fields.

Chandrasekhar Kota

1997-01-01T23:59:59.000Z

64

Neutron dosimetry in boron neutron capture therapy using aqueous solutions of lithium acetate  

Science Journals Connector (OSTI)

This paper presents the development of a dosimetry method, based on liquid scintillation (LS) counting of the tritium that is produced in aqueous solutions of lithium acetate, for the determination of the boron and nitrogen absorbed doses in-phantom in BNCT. The dosimeter is passive, integrating, approximately tissue equivalent, and insensitive to gamma rays and the elastic scattering of fast neutrons. The dosimetry method exhibits a response which is proportional to the boron and nitrogen absorbed doses and which can be calibrated to NIST standard solutions of water spiked with tritium. For 0.2 g of lithium acetate dissolved in a milliliter of water, the measured sensitivity is (1.73±0.04)×10?9 cpm per unit of thermal neutron fluence (in neutrons/cm2). For the LS analyzer that was used, the background signal was 12.84±0.02 cpm, yielding a thermal neutron fluence threshold for this detection method of approximately 7×109 neutrons/cm2.

L.J. Rakovan; T.E. Blue; A.L. Vest

1998-01-01T23:59:59.000Z

65

Development of the JAERI computational dosimetry system (JCDS) for boron neutron capture therapy. Cooperative research  

E-Print Network (OSTI)

The Neutron Beam Facility at JRR-4 enables us to carry out boron neutron capture therapy with epithermal neutron beam. In order to make treatment plans for performing the epithermal neutron beam BNCT, it is necessary to estimate radiation doses in a patient's head in advance. The JAERI Computational Dosimetry System (JCDS), which can estimate distributions of radiation doses in a patient's head by simulating in order to support the treatment planning for epithermal neutron beam BNCT, was developed. JCDS is a software that creates a 3-dimentional head model of a patient by using CT and MRI images, and that generates a input data file automatically for calculation of neutron flux and gamma-ray dose distributions in the brain with the Monte Carlo code MCNP, and that displays these dose distributions on the head model for dosimetry by using the MCNP calculation results. JCDS has any advantages as follows; By using CT data and MRI data which are medical images, a detail three-dimensional model of patient's head is...

Kumada, H; Matsumura, A; Nakagawa, Y; Nose, T; Torii, Y; Uchiyama, J; Yamamoto, K; Yamamoto, T

2003-01-01T23:59:59.000Z

66

A study on the optimum fast neutron flux for Boron Neutron Capture Therapy of deep-seated tumors  

Science Journals Connector (OSTI)

Abstract High-energy neutrons, named fast neutrons which have a number of undesirable biological effects on tissue, are a challenging problem in beam designing for Boron Neutron Capture Therapy, BNCT. In spite of this fact, there is not a widely accepted criterion to guide the beam designer to determine the appropriate contribution of fast neutrons in the spectrum. Although a number of researchers have proposed a target value for the ratio of fast neutron flux to epithermal neutron flux, it can be shown that this criterion may not provide the optimum treatment condition. This simulation study deals with the determination of the optimum contribution of fast neutron flux in the beam for BNCT of deep-seated tumors. Since the dose due to these high-energy neutrons damages shallow tissues, delivered dose to skin is considered as a measure for determining the acceptability of the designed beam. To serve this purpose, various beam shaping assemblies that result in different contribution of fast neutron flux are designed. The performances of the neutron beams corresponding to such configurations are assessed in a simulated head phantom. It is shown that the previously used criterion, which suggests a limit value for the contribution of fast neutrons in beam, does not necessarily provide the optimum condition. Accordingly, it is important to specify other complementary limits considering the energy of fast neutrons. By analyzing various neutron spectra, two limits on fast neutron flux are proposed and their validity is investigated. The results show that considering these limits together with the widely accepted IAEA criteria makes it possible to have a more realistic assessment of sufficiency of the designed beam. Satisfying these criteria not only leads to reduction of delivered dose to skin, but also increases the advantage depth in tissue and delivered dose to tumor during the treatment time. The Monte Carlo Code, MCNP-X, is used to perform these simulations.

Fatemeh S. Rasouli; S. Farhad Masoudi

2015-01-01T23:59:59.000Z

67

Optimization of Boron Neutron Capture Therapy for the Treatment of Undifferentiated Thyroid Cancer  

SciTech Connect

Purpose: To analyze the possible increase in efficacy of boron neutron capture therapy (BNCT) for undifferentiated thyroid carcinoma (UTC) by using p-boronophenylalanine (BPA) plus 2,4-bis ({alpha},{beta}-dihydroxyethyl)-deutero-porphyrin IX (BOPP) and BPA plus nicotinamide (NA) as a radiosensitizer of the BNCT reaction. Methods and Materials: Nude mice were transplanted with a human UTC cell line (ARO), and after 15 days they were treated as follows: (1) control, (2) NCT (neutrons alone), (3) NCT plus NA (100 mg/kg body weight [bw]/day for 3 days), (4) BPA (350 mg/kg bw) + neutrons, (5) BPA + NA + neutrons, and (6) BPA + BOPP (60 mg/kg bw) + neutrons. The flux of the mixed (thermal + epithermal) neutron beam was 2.8 x 10{sup 8} n/cm{sup 2}/sec for 83.4 min. Results: Neutrons alone or with NA caused some tumor growth delay, whereas in the BPA, BPA + NA, and BPA + BOPP groups a 100% halt of tumor growth was observed in all mice at 26 days after irradiation. When the initial tumor volume was 50 mm{sup 3} or less, complete remission was found with BPA + NA (2 of 2 mice), BPA (1 of 4), and BPA + BOPP (7 of 7). After 90 days of complete regression, recurrence of the tumor was observed in BPA + NA (2 of 2) and BPA + BOPP (1 of 7). The determination of apoptosis in tumor samples by measurements of caspase-3 activity showed an increase in the BNCT (BPA + NA) group at 24 h (p < 0.05 vs. controls) and after the first week after irradiation in the three BNCT groups. Terminal transferase dUTP nick end labeling analysis confirmed these results. Conclusions: Although NA combined with BPA showed an increase of apoptosis at early times, only the group irradiated after the combined administration of BPA and BOPP showed a significantly improved therapeutic response.

Dagrosa, Maria Alejandra; Thomasz, Lisa M.Sc. [Department of Radiobiology (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Longhino, Juan [Nuclear Reactor RA-6 (Bariloche Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Perona, Marina [Department of Radiobiology (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Calzetta, Osvaldo; Blaumann, Herman [Nuclear Reactor RA-6 (Bariloche Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Rebagliati, Raul Jimenez [Department of Chemistry (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Cabrini, Romulo [Department of Radiobiology (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Kahl, Steven [Department of Pharmaceutical Chemistry, University of California, San Francisco, CA (United States); Juvenal, Guillermo Juan [Department of Radiobiology (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Pisarev, Mario Alberto [Department of Radiobiology (Constituyentes Atomic Center), National Atomic Energy Commission of Argentina, Buenos Aires (Argentina); Department of Human Biochemistry, School of Medicine, University of Buenos Aires, Buenos Aires (Argentina)], E-mail: pisarev@cnea.gov.ar

2007-11-15T23:59:59.000Z

68

Boron neutron capture therapy (BNCT) for liver metastasis: therapeutic efficacy in an experimental model  

SciTech Connect

Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. The present study evaluates tumor control and potential radiotoxicity of BNCT in an experimental model of liver metastasis. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA–BNCT, boronophenylalanine (BPA) ? neutron irradiation; Beam only, neutron irradiation; Sham, matched manipulation. The total absorbed dose administered with BPA–BNCT was 13 ± 3 Gy in tumor and 9 ± 2 Gy in healthy liver. Three weeks posttreatment, the tumor surface area post-treatment/pre-treatment ratio was 0.46 ± 0.20 for BPA–BNCT, 2.7 ± 1.8 for Beam only and 4.5 ± 3.1 for Sham. The pre-treatment tumor nodule mass of 48 ± 19 mgfell significantly to 19 ± 16 mg for BPA–BNCT, but rose significantly to 140 ± 106 mg for Beam only and to 346 ± 302 mg for Sham. For both end points, the differences between the BPA–BNCT group and each of the other groups were statistically significant (ANOVA). No clinical, macroscopic or histological normal liver radiotoxicity was observed. It is concluded that BPA– BNCT induced a significant remission of experimental colorectal tumor nodules in liver with no contributory liver toxicity.

David W. Nigg

2012-08-01T23:59:59.000Z

69

Determination of Boron-Containing Compounds in Urine and Blood Plasma from Boron Neutron Capture Therapy Patients. The Importance of Using Coupled Techniques  

Science Journals Connector (OSTI)

Since only 10B (comprising 20% of elemental boron in nature) has the large cross-section for neutron capture reaction and is thereby useful for BNCT, the boron in the BPA transport molecules used in the Studsvik therapy was enriched with the 10B isotope to nearly 100%. ... A 1000 ?g/mL certified boric acid standard was purchased from BDH Chemicals (Poole, U.K.) and diluted to 2?10 ppm (?g/g) of boron in 0.1 M hydrochloric acid. ... To get a hint of the accuracy of the BPA determination, a spinach sample, IAEA-331, with a certified boron content of (37.6 ± 1.0) mg kg-1 was digested in nitric acid in a steel bomb and determined with ICP-AES. ...

Eva Svantesson; Jacek Capala; Karin E. Markides; Jean Pettersson

2002-09-12T23:59:59.000Z

70

Molecular Medicine: Synthesis and In Vivo Detection of Agents for use in Boron Neutron Capture Therapy. Final Report  

SciTech Connect

The primary objective of the project was the development of in vivo methods for the detection and evaluation of tumors in humans. The project was focused on utilizing positron emission tomography (PET) to monitor the distribution and pharamacokinetics of a current boron neutron capture therapy (BNCT) agent, p-boronophenylalanine (BPA) by labeling it with a fluorine-18, a positron emitting isotope. The PET data was then used to develop enhanced treatment planning protocols. The study also involved the synthesis of new tumor selective BNCTagents that could be labeled with radioactive nuclides for the in vivo detection of boron.

Kabalka, G. W.

2005-06-28T23:59:59.000Z

71

Improvement of the Tumor-Suppressive Effect of Boron Neutron Capture Therapy for Amelanotic Melanoma by Intratumoral Injection of the Tyrosinase Gene  

Science Journals Connector (OSTI)

...30 Smith DR, Chandra S, Barth RF, Yang W, Joel DD, Coderre JA. Quantitative imaging and microlocalization of boron-10 in brain tumors and infiltrating tumor cells by SIMS ion microscopy: relevance to neutron capture therapy. Cancer Res...

Norimasa Morita; Junichi Hiratsuka; Hirohumi Kondoh; Masako Uno; Tomoyuki Asano; Yoko Niki; Yoshinori Sakurai; Koji Ono; Tamotsu Harada; Yoshinari Imajo

2006-04-01T23:59:59.000Z

72

A Bystander Effect Observed in Boron Neutron Capture Therapy: A Study of the Induction of Mutations in the HPRT Locus  

SciTech Connect

Purpose: To investigate bystander mutagenic effects induced by {alpha}-particles during boron neutron capture therapy, we mixed cells that were electroporated with borocaptate sodium (BSH), which led to the accumulation of {sup 10}B inside the cells, and cells that did not contain the boron compound. The BSH-containing cells were irradiated with {alpha}-particles produced by the {sup 10}B(n,{alpha}){sup 7}Li reaction, whereas cells without boron were affected only by the {sup 1}H(n,{gamma}){sup 2}H and {sup 14}N(n,{rho}){sup 14}C reactions. Methods and Materials: The lethality and mutagenicity measured by the frequency of mutations induced in the hypoxanthine-guanine phosphoribosyltransferase locus were examined in Chinese hamster ovary cells irradiated with neutrons (Kyoto University Research Reactor: 5 MW). Neutron irradiation of 1:1 mixtures of cells with and without BSH resulted in a survival fraction of 0.1, and the cells that did not contain BSH made up 99.4% of the resulting cell population. The molecular structures of the mutations were determined using multiplex polymerase chain reactions. Results: Because of the bystander effect, the frequency of mutations increased in the cells located nearby the BSH-containing cells compared with control cells. Molecular structural analysis indicated that most of the mutations induced by the bystander effect were point mutations and that the frequencies of total and partial deletions induced by the bystander effect were less than those induced by the original neutron irradiation. Conclusion: These results suggested that in boron neutron capture therapy, the mutations caused by the bystander effect and those caused by the original neutron irradiation are induced by different mechanisms.

Kinashi, Yuko [Research Reactor Institute, Kyoto University, Osaka (Japan)]. E-mail: kinashi@rri.kyoto-u.ac.jp; Masunaga, Shinichiro [Research Reactor Institute, Kyoto University, Osaka (Japan); Nagata, Kenji [Research Reactor Institute, Kyoto University, Osaka (Japan); Suzuki, Minoru [Research Reactor Institute, Kyoto University, Osaka (Japan); Takahashi, Sentaro [National Institute of Radiological Sciences, Chiba (Japan); Ono, Koji [Research Reactor Institute, Kyoto University, Osaka (Japan)

2007-06-01T23:59:59.000Z

73

Evaluation of Micronucleus Induction in Lymphocytes of Patients Following Boron-Neutron-Capture-Therapy: A Comparison with Thyroid Cancer Patients treated with radioiodine  

Science Journals Connector (OSTI)

......radiotherapy modality that combines a stable isotope of boron (10 B), which releases alpha-paticles, and a beam of...Kobayashi T. and Kanda K. (1982) Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radiation......

Yuko Kinashi; Yoshinori Sakurai; Shinichiro Masunaga; Minoru Suzuki; Kenji Nagata; Koji Ono

2007-05-01T23:59:59.000Z

74

Model studies directed toward the boron neutron-capture therapy of cancer: boron delivery to murine tumors with liposomes.  

Science Journals Connector (OSTI)

...requires the selective concentration of boron-10 within malignant tumors. The potential...requires the selective concentration of boron-10 within malignant tumors. The potential...the selective con- centration of boron-10 within malignant tumors. The potential...

K Shelly; D A Feakes; M F Hawthorne; P G Schmidt; T A Krisch; W F Bauer

1992-01-01T23:59:59.000Z

75

Combination of the vascular targeting agent ZD6126 with boron neutron capture therapy  

SciTech Connect

Purpose: The aim of this study was to evaluate the antitumor efficacy of the vascular targeting agent ZD6126 (N-acetylcochinol-O-phosphate) in the rodent squamous cell carcinoma (SCC) VII carcinoma model, in combination with boron neutron capture therapy (BNCT). Methods and materials: Sodium borocaptate-{sup 10}B (BSH, 125 mg/kg, i.p.) or l-p-boronophenylalanine-{sup 10}B (BPA, 250 mg/kg, i.p.) was injected into SCC VII tumor-bearing mice, and 15 min later, ZD6126 (100 mg/kg, i.p.) was administered. Then, the {sup 10}B concentrations in tumors and normal tissues were measured by prompt {gamma}-ray spectrometry. On the other hand, for the thermal neutron beam exposure experiment, SCC VII tumor-bearing mice were continuously given 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) cells in the tumors, followed by treatment with a {sup 10}B-carrier and ZD6126 in the same manner as the above-mentioned {sup 10}B pharmacokinetics analyses. To obtain almost similar intratumor {sup 10}B concentrations during neutron exposure, thermal neutron beam irradiation was started from the time point of 30 min after injection of BSH only, 90 min after BSH injection for combination with ZD6126, 120 min after the injection of BPA only, and 180 min after BPA injection for combination with ZD6126. Right after irradiation, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (quiescent [Q] cells) was determined using immunofluorescence staining for BrdU. Meanwhile, the MN frequency in total (P + Q) tumor cells was determined from the tumors that were not pretreated with BrdU. The clonogenic cell survival assay was also performed in mice given no BrdU. Results: Pharmacokinetics analyses showed that combination with ZD6126 greatly increased the {sup 10}B concentrations in tumors after 60 min after BSH injection and after 120 min after BPA injection. The concentrations of {sup 10}B from BSH in normal tissues were also raised by combination with ZD6126, although not so clearly as those in tumors. Combination with ZD6126 had almost no effect on the concentrations of {sup 10}B from BPA in normal tissues. The clonogenic surviving fractions of total tumor cells and the MN frequencies of both total and Q tumor cells were reduced and increased by combination with ZD6126, respectively, whether BSH or BPA was employed. However, the degrees of these changes in the clonogenic surviving fractions and the MN frequencies were more obviously observed in tumors from BSH-injected mice than from BPA-injected mice, and in Q tumor cells than in total tumor cells regardless of the employed {sup 10}B-carrier. Conclusions: Combination with ZD6126 was regarded as more promising in BSH-BNCT than BPA-BNCT, and more effective for enhancing the sensitivity of the Q tumor cells than that of the total tumor cells. This resulted in the decrease in the extended difference in the sensitivity between the total and Q tumor cells caused by the use of {sup 10}B-carrier for BNCT.

Masunaga, Shin-ichiro [Radiation Oncology Research Laboratory, Research Reactor Institute, Kyoto University, Osaka (Japan)]. E-mail: smasuna@rri.kyoto-u.ac.jp; Sakurai, Yoshinori [Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Suzuki, Minoru [Radiation Oncology Research Laboratory, Research Reactor Institute, Kyoto University, Osaka (Japan); Nagata, Kenji [Radiation Oncology Research Laboratory, Research Reactor Institute, Kyoto University, Osaka (Japan); Maruhashi, Akira [Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Kinash, Yuko [Division of Radiation Safety, Research Reactor Institute, Kyoto University, Osaka (Japan); Ono, Koji [Radiation Oncology Research Laboratory, Research Reactor Institute, Kyoto University, Osaka (Japan)

2004-11-01T23:59:59.000Z

76

Neutron capture therapies  

DOE Patents (OSTI)

In one embodiment there is provided an application of the .sup.10 B(n,.alpha.).sup.7 Li nuclear reaction or other neutron capture reactions for the treatment of rheumatoid arthritis. This application, called Boron Neutron Capture Synovectomy (BNCS), requires substantially altered demands on neutron beam design than for instance treatment of deep seated tumors. Considerations for neutron beam design for the treatment of arthritic joints via BNCS are provided for, and comparisons with the design requirements for Boron Neutron Capture Therapy (BNCT) of tumors are made. In addition, exemplary moderator/reflector assemblies are provided which produce intense, high-quality neutron beams based on (p,n) accelerator-based reactions. In another embodiment there is provided the use of deuteron-based charged particle reactions to be used as sources for epithermal or thermal neutron beams for neutron capture therapies. Many d,n reactions (e.g. using deuterium, tritium or beryllium targets) are very prolific at relatively low deuteron energies.

Yanch, Jacquelyn C. (Cambridge, MA); Shefer, Ruth E. (Newton, MA); Klinkowstein, Robert E. (Winchester, MA)

1999-01-01T23:59:59.000Z

77

Experimental and Simulated Characterization of a Beam Shaping Assembly for Accelerator- Based Boron Neutron Capture Therapy (AB-BNCT)  

SciTech Connect

In the frame of the construction of a Tandem Electrostatic Quadrupole Accelerator facility devoted to the Accelerator-Based Boron Neutron Capture Therapy, a Beam Shaping Assembly has been characterized by means of Monte-Carlo simulations and measurements. The neutrons were generated via the {sup 7}Li(p, n){sup 7}Be reaction by irradiating a thick LiF target with a 2.3 MeV proton beam delivered by the TANDAR accelerator at CNEA. The emerging neutron flux was measured by means of activation foils while the beam quality and directionality was evaluated by means of Monte Carlo simulations. The parameters show compliance with those suggested by IAEA. Finally, an improvement adding a beam collimator has been evaluated.

Burlon, Alejandro A.; Valda, Alejandro A. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av Gral. Paz 1499, San Martin (1650) (Argentina); Escuela de Ciencia y Tecnologia, Universidad de San Martin, M. Irigoyen 3100 (1650), San Martin (Argentina); Girola, Santiago [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av Gral. Paz 1499, San Martin (1650) (Argentina); Escuela de Ciencia y Tecnologia, Universidad de San Martin, M. Irigoyen 3100 (1650), San Martin (Argentina); Vidt Centro Medico, Vidt 1924 (1425), Buenos Aires (Argentina); Minsky, Daniel M.; Kreiner, Andres J. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, Av Gral. Paz 1499, San Martin (1650) (Argentina); Escuela de Ciencia y Tecnologia, Universidad de San Martin, M. Irigoyen 3100 (1650), San Martin (Argentina); CONICET, Av Rivadavia 1917 (1033), Buenos Aires (Argentina)

2010-08-04T23:59:59.000Z

78

Evaluation of Human Thymidine Kinase 1 Substrates as New Candidates for Boron Neutron Capture Therapy  

Science Journals Connector (OSTI)

...candidate for selective delivery of boron-10 to malignant cells, and additional...fission reactions that occur when boron-10 (10B) is irradiated with low-energy...candidate for selective delivery of boron-10 to malignant cells, and additional...

Ashraf S. Al-Madhoun; Jayaseharan Johnsamuel; Rolf F. Barth; Werner Tjarks; Staffan Eriksson

2004-09-01T23:59:59.000Z

79

Positron emission tomography-based boron neutron capture therapy using boronophenylalanine for high-grade gliomas: part I.  

Science Journals Connector (OSTI)

...for high-grade gliomas: part I Determination of tumor boron-10 (10B) levels is required for accurate neutron dosimetry...high-grade gliomas: part I. | Determination of tumor boron-10 (10B) levels is required for accurate neutron dosimetry...

Y Imahori; S Ueda; Y Ohmori; K Sakae; T Kusuki; T Kobayashi; M Takagaki; K Ono; T Ido; R Fujii

1998-08-01T23:59:59.000Z

80

Capillary electrophoresis–electrospray mass spectrometry and HR–ICP–MS for the detection and quantification of 10B-boronophenylalanine (10B–BPA) used in boron neutron capture therapy  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is a bimodal radiotherapeutic treatment based on the irradiation of neoplastic tissues with neutrons after the tissues have selectively accumulated molecules loaded with nu...

Aurélien Pitois; Laura Aldave de las Heras…

2006-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
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81

Quantitative Imaging and Microlocalization of Boron-10 in Brain Tumors and Infiltrating Tumor Cells by SIMS Ion Microscopy: Relevance to Neutron Capture Therapy  

Science Journals Connector (OSTI)

...Tumors and Infiltrating Tumor Cells by SIMS Ion MicroscopyRelevance to Neutron Capture...of boron delivery agents. However, the SIMS-based technique of ion microscopy (14...these analytes are strong indicators that SIMS matrix effects 8 are minimal and that the...

Duane R. Smith; Subhash Chandra; Rolf F. Barth; Weilian Yang; Darrel D. Joel; Jeffrey A. Coderre

2001-11-15T23:59:59.000Z

82

User's manual of a supporting system for treatment planning in boron neutron capture therapy. JAERI computational dosimetry system  

E-Print Network (OSTI)

A boron neutron capture therapy (BNCT) with epithermal neutron beam is expected to treat effectively for malignant tumor that is located deeply in the brain. It is indispensable to estimate preliminarily the irradiation dose in the brain of a patient in order to perform the epithermal neutron beam BNCT. Thus, the JAERI Computational Dosimetry System (JCDS), which can calculate the dose distributions in the brain, has been developed. JCDS is a software that creates a 3-dimensional head model of a patient by using CT and MRI images and that generates a input data file automatically for calculation neutron flux and gamma-ray dose distribution in the brain by the Monte Carlo code: MCNP, and that displays the dose distribution on the head model for dosimetry by using the MCNP calculation results. JCDS has any advantages as follows; By treating CT data and MRI data which are medical images, a detail three-dimensional model of patient's head is able to be made easily. The three-dimensional head image is editable to ...

Kumada, H

2002-01-01T23:59:59.000Z

83

Homogeneous immunoconjugates for boron neutron-capture therapy: Design, synthesis, and preliminary characterization  

Science Journals Connector (OSTI)

...require the efficient delivery of 103 boron-10 atoms by each antigen-binding protein...concentrations of the stable isotope boron-10 ( 10 B) in a tumor target, followed...the efficient delivery of 10(3) boron-10 atoms by each antigen-binding protein...

Lufeng Guan; Letitia A. Wims; Robert R. Kane; Mark B. Smuckler; Sherie L. Morrison; M. Frederick Hawthorne

1998-01-01T23:59:59.000Z

84

Synthesis and in vivo murine evaluation of Na4[1-(1?-B10H9)-6-SHB10H8] as a potential agent for boron neutron capture therapy  

Science Journals Connector (OSTI)

...is based on the propensity of the boron-10 isotope to capture thermal neutrons...the selective concentration of boron-10 nuclei within tumor cells, followed...high yield reactions, amenable to boron-10 enrichment, from decaborane, B 10 H 14 (6...

Debra A. Feakes; R. Corey Waller; Deborah K. Hathaway; Veronica S. Morton

1999-01-01T23:59:59.000Z

85

Computational validation of the stereology principle applied to the microdosimetry of boron neutron capture therapy  

Science Journals Connector (OSTI)

High resolution quantitative autoradiography (HRQAR) is a novel technique that has been developed in our laboratory and applied to the microdosimetry of boronneutron capture therapy (BNCT). High resolution quantitative autoradiography is employed to define the microdistribution of boron-10 atoms within a 1–2 ?m frozen tissue section. This microdistribution is used as input to a novel two-dimensional Monte Carlo charged particle transport calculation that computes various microdosimetric parameters such as the number of nuclear “hits ” energy absorbed in the nuclei etc. within the environment of actual tissue morphology (i.e. cell nuclei cytoplasm and intracellular space). Stereological transformation is then implemented to transform the two-dimensional calculations into effectively three-dimensional results. In the present study no seek to demonstrate the validity of the surrogate two-dimensional 2-D computation as being quantitatively equivalent to a hypothetical full 3-D calculation. The results show that within the limitations of the test parameters used the surrogate 2-D and 3-D results are completely equivalent within the statistical constraints of the Monte Carlo calculations. Limitations of this approach also are evaluated including a Monte Carlo calculation of the influence of the thickness of the histological tissue section and the track detector and the influence of 4 He and 7 Li particle lateral and range straggling.

C. S. Yam; R. G. Zamenhof

2000-01-01T23:59:59.000Z

86

Thymidine kinase 1 as a molecular target for boron neutron capture therapy of brain tumors  

Science Journals Connector (OSTI)

...that is based on the selective delivery of nonradioactive boron-10 ( 10 B), followed by irradiation with either low energy...CED N5–2OH) 17.3 ± 4.3 Boron-10 enriched N5–2OH was administered i.c. by means of...

Rolf F. Barth; Weilian Yang; Gong Wu; Michele Swindall; Youngjoo Byun; Sureshbabu Narayanasamy; Werner Tjarks; Kevin Tordoff; Melvin L. Moeschberger; Staffan Eriksson; Peter J. Binns; Kent J. Riley

2008-01-01T23:59:59.000Z

87

First Evaluation of the Biologic Effectiveness Factors of Boron Neutron Capture Therapy (BNCT) in a Human Colon Carcinoma Cell Line  

SciTech Connect

Purpose: DNA lesions produced by boron neutron capture therapy (BNCT) and those produced by gamma radiation in a colon carcinoma cell line were analyzed. We have also derived the relative biologic effectiveness factor (RBE) of the neutron beam of the RA-3- Argentine nuclear reactor, and the compound biologic effectiveness (CBE) values for p-boronophenylalanine ({sup 10}BPA) and for 2,4-bis ({alpha},{beta}-dihydroxyethyl)-deutero-porphyrin IX ({sup 10}BOPP). Methods and Materials: Exponentially growing human colon carcinoma cells (ARO81-1) were distributed into the following groups: (1) BPA (10 ppm {sup 10}B) + neutrons, (2) BOPP (10 ppm {sup 10}B) + neutrons, (3) neutrons alone, and (4) gamma rays ({sup 60}Co source at 1 Gy/min dose-rate). Different irradiation times were used to obtain total absorbed doses between 0.3 and 5 Gy ({+-}10%) (thermal neutrons flux = 7.5 10{sup 9} n/cm{sup 2} sec). Results: The frequency of micronucleated binucleated cells and the number of micronuclei per micronucleated binucleated cells showed a dose-dependent increase until approximately 2 Gy. The response to gamma rays was significantly lower than the response to the other treatments (p < 0.05). The irradiations with neutrons alone and neutrons + BOPP showed curves that did not differ significantly from, and showed less DNA damage than, irradiation with neutrons + BPA. A decrease in the surviving fraction measured by 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolium bromide (MTT) assay as a function of the absorbed dose was observed for all the treatments. The RBE and CBE factors calculated from cytokinesis block micronucleus (CBMN) and MTT assays were, respectively, the following: beam RBE: 4.4 {+-} 1.1 and 2.4 {+-} 0.6; CBE for BOPP: 8.0 {+-} 2.2 and 2.0 {+-} 1; CBE for BPA: 19.6 {+-} 3.7 and 3.5 {+-} 1.3. Conclusions: BNCT and gamma irradiations showed different genotoxic patterns. To our knowledge, these values represent the first experimental ones obtained for the RA-3 in a biologic model and could be useful for future experimental studies for the application of BNCT to colon carcinoma.

Dagrosa, Maria Alejandra, E-mail: dagrosa@cnea.gov.a [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); National Research Council (Argentina); Crivello, Martin [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires(Argentina); Perona, Marina [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); National Research Council (Argentina); Thorp, Silvia; Santa Cruz, Gustavo Alberto [Department of Instrumentation and Control, National Atomic Energy Commission, Buenos Aires (Argentina); Pozzi, Emiliano [Argentina Reactor, National Atomic Energy Commission, Buenos Aires (Argentina); Casal, Mariana [Institute of Oncology 'Angel H. Roffo', University of Buenos Aires (Argentina); Thomasz, Lisa; Cabrini, Romulo [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); Kahl, Steven [Department of Pharmaceutical Chemistry, University of California, San Francisco, CA (United States); Juvenal, Guillermo Juan [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); National Research Council (Argentina); Pisarev, Mario Alberto [Department of Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); National Research Council (Argentina); Department of Human Biochemistry, School of Medicine, University of Buenos Aires (Argentina)

2011-01-01T23:59:59.000Z

88

Quantitative Neutron Capture Radiography for Studying the Biodistribution of Tumor-seeking Boron-containing Compounds  

Science Journals Connector (OSTI)

...detectors. Phys. Med. Biol., 28:1453-1457, 1983. 13. Amano, K., and Sweet, W. H. a-Autoradiography of boron-10 compound distribution in tissue by use of superimposition technique. Nippon Acta Radio!., 33: 267-272, 1973...

Detlef Gabel; Hartmut Holstein; Börje Larsson; Lillian Gille; Gunilla Ericson; Donald Sacker; Prantika Som; Ralph G. Fairchild

1987-10-15T23:59:59.000Z

89

Neutron-capture therapy of human cancer: in vitro results on the preparation of boron-labeled antibodies to carcinoembryonic antigen  

Science Journals Connector (OSTI)

...based on the nuclear property of boron-10 to absorb thermal neutrons, releasing...normal tissue and in tissue containing boron-10 has been investigated (2), and...trials was attributed to the low boron-10 concentration differential between...

E Mizusawa; H L Dahlman; S J Bennett; D M Goldenberg; M F Hawthorne

1982-01-01T23:59:59.000Z

90

Lithium-6 filter for a fission converter-based Boron Neutron Capture Therapy irradiation facility beam  

E-Print Network (OSTI)

(cont.) A storage system was designed to contain the lithium-6 filter safely when it is not in use. A mixed field dosimetry method was used to measure the photon, thermal neutron and fast neutron dose. The measured advantage ...

Gao, Wei, Ph. D.

2005-01-01T23:59:59.000Z

91

Monte Carlo calculations of lung dose in ORNL phantom for boron neutron capture therapy  

Science Journals Connector (OSTI)

......radiation is localised inside the cells containing boron. This advantage is even more pronounced when the whole organs such as brain, liver, lung, pancreas and prostate(2) are treated. In clinical application of BNCT, 10B compounds such as BPA (boronophenylalanine......

D. Krstic; V. M. Markovic; Z. Jovanovic; B. Milenkovic; D. Nikezic; J. Atanackovic

2014-10-01T23:59:59.000Z

92

Optimisation of Neutron Capture Radiography for Analysis of Boron-10 in Tissues  

Science Journals Connector (OSTI)

The 14N(n,p)14C reaction concomitantly occurs with the10B(n,?)7Li reaction in tissue. Although the cross section of nitrogen-14 is much lower than that for boron-10, the abundance of the former in tissue ... and ...

Haider A. Meriaty; Barry J. Allen

1993-01-01T23:59:59.000Z

93

Brain Tolerance in Dogs to Boron Neutron Capture Therapy with Borocaptate Sodium (BSH) or Boronophenylalanine (BPA)  

Science Journals Connector (OSTI)

Research programs investigating the potential use of BNCT for brain tumors have been initiated in Europe and in the U.S. using epithermal neutron beams and either borocaptate sodium (BSH) or boronophenylalanine (

R. Huiskamp; P. R. Gavin; J. A. Coderre; K. H. I. Philipp…

1996-01-01T23:59:59.000Z

94

Computer simulation of neutron capture therapy.  

E-Print Network (OSTI)

Analytical methods are developed to simulate on a large digital computer the production and use of reactor neutron beams f or boron capture therapy of brain tumors. The simulation accounts for radiation dose distributions ...

Olson, Arne Peter

1967-01-01T23:59:59.000Z

95

Computer simulation of neutron capture therapy  

E-Print Network (OSTI)

Analytical methods are developed to simulate on a large digital computer the production and use of reactor neutron beams f or boron capture therapy of brain tumors. The simulation accounts for radiation dose distributions ...

Olson, Arne Peter

1967-01-01T23:59:59.000Z

96

Impact of intra-arterial administration of boron compounds on dose-volume histograms in boron neutron capture therapy for recurrent head-and-neck tumors  

SciTech Connect

Purpose: To analyze the dose-volume histogram (DVH) of head-and-neck tumors treated with boron neutron capture therapy (BNCT) and to determine the advantage of the intra-arterial (IA) route over the intravenous (IV) route as a drug delivery system for BNCT. Methods and Materials: Fifteen BNCTs for 12 patients with recurrent head-and-neck tumors were included in the present study. Eight irradiations were done after IV administration of boronophenylalanine and seven after IA administration. The maximal, mean, and minimal doses given to the gross tumor volume were assessed using a BNCT planning system. Results: The results are reported as median values with the interquartile range. In the IA group, the maximal, mean, and minimal dose given to the gross tumor volume was 68.7 Gy-Eq (range, 38.8-79.9), 45.0 Gy-Eq (range, 25.1-51.0), and 13.8 Gy-Eq (range, 4.8-25.3), respectively. In the IV group, the maximal, mean, and minimal dose given to the gross tumor volume was 24.2 Gy-Eq (range, 21.5-29.9), 16.4 Gy-Eq (range, 14.5-20.2), and 7.8 Gy-Eq (range, 6.8-9.5), respectively. Within 1-3 months after BNCT, the responses were assessed. Of the 6 patients in the IV group, 2 had a partial response, 3 no change, and 1 had progressive disease. Of 4 patients in the IA group, 1 achieved a complete response and 3 a partial response. Conclusion: Intra-arterial administration of boronophenylalanine is a promising drug delivery system for head-and-neck BNCT.

Suzuki, Minoru [Particle Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka (Japan)]. E-mail: msuzuki@rri.kyoto-u.ac.jp; Sakurai, Yoshinori [Division of Medical Physics, Department of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Nagata, Kenji [Particle Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka (Japan); Kinashi, Yuko [Particle Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka (Japan); Masunaga, Shinichiro [Particle Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka (Japan); Ono, Koji [Particle Oncology Research Center, Research Reactor Institute, Kyoto University, Osaka (Japan); Maruhashi, Akira [Division of Medical Physics, Department of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Kato, Ituro [Department of Oral and Maxillofacial Surgery II, Osaka University Graduate School of Dentistry, Osaka (Japan); Fuwa, Nobukazu [Department of Radiation Oncology, Aichi Cancer Center, Aichi (Japan); Hiratsuka, Junichi [Department of Radiation Oncology, Kawasaki Medical School, Okayama (Japan); Imahori, Yoshio [Cancer Intelligence Care Systems, Inc., Tokyo (Japan)

2006-12-01T23:59:59.000Z

97

Feasibility of boron neutron capture therapy (BNCT) for malignant pleural mesothelioma from a viewpoint of dose distribution analysis  

SciTech Connect

Purpose: To investigate the feasibility of boron neutron capture therapy (BNCT) for malignant pleural mesothelioma (MPM) from a viewpoint of dose distribution analysis using Simulation Environment for Radiotherapy Applications (SERA), a currently available BNCT treatment planning system. Methods and Materials: The BNCT treatment plans were constructed for 3 patients with MPM using the SERA system, with 2 opposed anterior-posterior beams. The {sup 1}B concentrations in the tumor and normal lung in this study were assumed to be 84 and 24 ppm, respectively, and were derived from data observed in clinical trials. The maximum, mean, and minimum doses to the tumors and the normal lung were assessed for each plan. The doses delivered to 5% and 95% of the tumor volume, D{sub 05} and D{sub 95}, were adopted as the representative dose for the maximum and minimum dose, respectively. Results: When the D{sub 05} to the normal ipsilateral lung was 5 Gy-Eq, the D{sub 95} and mean doses delivered to the normal lung were 2.2-3.6 and 3.5-4.2 Gy-Eq, respectively. The mean doses delivered to the tumors were 22.4-27.2 Gy-Eq. The D{sub 05} and D{sub 95} doses to the tumors were 9.6-15.0 and 31.5-39.5 Gy-Eq, respectively. Conclusions: From a viewpoint of the dose-distribution analysis, BNCT has the possibility to be a promising treatment for MPM patients who are inoperable because of age and other medical illnesses.

Suzuki, Minoru [Particle Oncology Research Center, Osaka (Japan)]. E-mail: msuzuki@rri.kyoto-u.ac.jp; Sakurai, Yoshinori [Division of Medical Physics, Department of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Masunaga, Shinichiro [Particle Oncology Research Center, Osaka (Japan); Kinashi, Yuko [Particle Oncology Research Center, Osaka (Japan); Nagata, Kenji [Particle Oncology Research Center, Osaka (Japan); Maruhashi, Akira [Division of Medical Physics, Department of Radiation Life Science, Research Reactor Institute, Kyoto University, Osaka (Japan); Ono, Koji [Particle Oncology Research Center, Osaka (Japan)

2006-12-01T23:59:59.000Z

98

Boron-10 Prompt Gamma Analysis Using a Diffracted Neutron Beam  

Science Journals Connector (OSTI)

A prompt gamma neutron activation analysis (PGNAA) facility has been built at the 5 MW MITR-II Research Reactor to support our ongoing boron neutron capture therapy (NCT) program. This facility is used to dete...

R. Rogus; O. K. Harling; I. Olmez…

1992-01-01T23:59:59.000Z

99

Thiourea derivatives, methods of their preparation and their use in neutron capture therapy of malignant melanoma  

DOE Patents (OSTI)

The present invention pertains to boron containing thiouracil derivatives, their method of preparations, and their use in the therapy of malignant melanoma using boron neutron capture therapy.

Gabel, Detlef (Bremen, DE)

1991-01-01T23:59:59.000Z

100

Compact D-D Neutron Source-Driven Subcritical Multiplier and Beam-Shaping Assembly for Boron Neutron Capture Therapy  

SciTech Connect

This work assesses the feasibility of using a small, safe, and inexpensive keff 0.98 subcritical fission assembly [subcritical neutron multiplier (SCM)] to amplify the treatment neutron beam intensity attainable from a compact deuterium-deuterium (D-D) fusion neutron source delivering [approximately]1012 n/s. The objective is to reduce the treatment time for deep-seated brain tumors to [approximately]1 h. The paper describes the optimal SCM design and two optimal beam-shaping assemblies (BSAs) - one designed to maximize the dose rate and the other designed to maximize the total dose that can be delivered to a deep-seated tumor. The neutron beam intensity amplification achieved with the optimized SCM and BSA results in an increase in the treatment dose rate by a factor of 18: from 0.56 Gy/h without the SCM to 10.1 Gy/h. The entire SCM is encased in an aluminum structure. The total amount of 20% enriched uranium required for the SCM is 8.5 kg, and the cost (not including fabrication) is estimated to be less than $60,000. The SCM power level is estimated at 400 W when driven by a 1012 n/s D-D neutron source. This translates into consumption of only [approximately]0.6% of the initially loaded 235U atoms during 50 years of continuous operation and implies that the SCM could operate continuously for the entire lifetime of the facility without refueling. Cooling the SCM does not pose a challenge; it may be accomplished by natural circulation as the maximum heat flux is only 0.034 W/cm2.

Francesco Ganda; Jasmina Vujic; Ehud Greenspan; Ka-Ngo Leung

2010-12-01T23:59:59.000Z

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101

"Sequential” Boron Neutron Capture Therapy (BNCT): A Novel Approach to BNCT for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model  

SciTech Connect

Boron Neutron Capture Therapy (BNCT) is a binary treatment modality that involves the selective accumulation of 10B carriers in tumors followed by irradiation with a thermal or epithermal neutron beam. The minor abundance stable isotope of boron, 10B, interacts with low energy (thermal) neutrons to produce high linear energy transfer (LET) a-particles and 7Li ions. These disintegration products are known to have a high relative biological effectiveness (RBE). Their short range (<10 {micro}m) would limit the damage to cells containing 10B (1,2). Thus, BNCT would target tumor tissue selectively, sparing normal tissue. Clinical trials of BNCT for the treatment of glioblastoma multiforme and/or melanoma and, more recently, head and neck tumors and liver metastases, using boronophenylalanine (BPA) or sodium mercaptoundecahydrododecaborane (BSH) as the 10B carriers, have been performed or are underway in Argentina, Japan, the US and Europe (e.g. 3-8). To date, the clinical results have shown a potential, albeit inconclusive, therapeutic advantage for this technique. Contributory translational studies have been carried out employing a variety of experimental models based on the implantation of tumor cells in normal tissue (e.g. 5).

Ana J. Molinari; Andrea Monti Hughes; Elisa M. Heber; Marcela A. Garabalino; Veronica A. Trivillin; Amanda E. Schwint; Emiliano C. C. Pozzi; Maria E. Itoiz; Silvia I. Thorp; Romina F. Aromando; David W. Nigg; Jorge Quintana; Gustavo A. Santa Cruz

2011-04-01T23:59:59.000Z

102

Workshop on neutron capture therapy  

SciTech Connect

Potentially optimal conditions for Neutron Capture Therapy (NCT) may soon be in hand due to the anticipated development of band-pass filtered beams relatively free of fast neutron contaminations, and of broadly applicable biomolecules for boron transport such as porphyrins and monoclonal antibodies. Consequently, a number of groups in the US are now devoting their efforts to exploring NCT for clinical application. The purpose of this Workshop was to bring these groups together to exchange views on significant problems of mutual interest, and to assure a unified and effective approach to the solutions. Several areas of preclinical investigation were deemed to be necessary before it would be possible to initiate clinical studies. As neither the monomer nor the dimer of sulfhydryl boron hydride is unequivocally preferable at this time, studies on both compounds should be continued until one is proven superior.

Fairchild, R.G.; Bond, V.P. (eds.)

1986-01-01T23:59:59.000Z

103

Model studies directed toward the application of boron neutron capture therapy to rheumatoid arthritis: Boron delivery by liposomes in rat?collagen-induced?arthritis  

Science Journals Connector (OSTI)

...rheumatoid arthritis requires the selective delivery of the boron-10 isotope to the synovitic tissue. The use of liposomes...rheumatoid arthritis requires the selective delivery of the boron-10 isotope to the synovitic tissue. The use of liposomes...

Rachel A. Watson-Clark; Mona Lisa Banquerigo; Kenneth Shelly; M. Frederick Hawthorne; Ernest Brahn

1998-01-01T23:59:59.000Z

104

Neutron detectors comprising boron powder  

SciTech Connect

High-efficiency neutron detector substrate assemblies comprising a first conductive substrate, wherein a first side of the substrate is in direct contact with a first layer of a powder material comprising .sup.10boron, .sup.10boron carbide or combinations thereof, and wherein a conductive material is in proximity to the first layer of powder material; and processes of making said neutron detector substrate assemblies.

Wang, Zhehui; Morris, Christopher; Bacon, Jeffrey Darnell; Makela, Mark F; Spaulding, Randy Jay

2013-05-21T23:59:59.000Z

105

Biodistribution of the boron carriers boronophenylalanine (BPA) and/or decahydrodecaborate (GB-10) for Boron Neutron Capture Therapy (BNCT) in an experimental model of lung metastases  

SciTech Connect

BNCT was proposed for the treatment of diffuse, non-resectable tumors in the lung. We performed boron biodistribution studies with 5 administration protocols employing the boron carriers BPA and/or GB-10 in an experimental model of disseminated lung metastases in rats. All 5 protocols were non-toxic and showed preferential tumor boron uptake versus lung. Absolute tumor boron concentration values were therapeutically useful (25–76 ppm) for 3 protocols. Dosimetric calculations indicate that BNCT at RA-3 would be potentially therapeutic without exceeding radiotolerance in the lung.

D.W. Nigg; Various Others

2014-06-01T23:59:59.000Z

106

Biodistribution of the boron carriers boronophenylalanine (BPA) and/or decahydrodecaborate (GB-10) for Boron Neutron Capture Therapy (BNCT) in an experimental model of lung metastases  

Science Journals Connector (OSTI)

Abstract BNCT was proposed for the treatment of diffuse, non-resectable tumors in the lung. We performed boron biodistribution studies with 5 administration protocols employing the boron carriers BPA and/or GB-10 in an experimental model of disseminated lung metastases in rats. All 5 protocols were non-toxic and showed preferential tumor boron uptake versus lung. Absolute tumor boron concentration values were therapeutically useful (25–76 ppm) for 3 protocols. Dosimetric calculations indicate that BNCT at RA-3 would be potentially therapeutic without exceeding radiotolerance in the lung.

V.A. Trivillin; M.A. Garabalino; L.L. Colombo; S.J. González; R.O. Farías; A. Monti Hughes; E.C.C. Pozzi; S. Bortolussi; S. Altieri; M.E. Itoiz; R.F. Aromando; D.W. Nigg; A.E. Schwint

2014-01-01T23:59:59.000Z

107

l-Amino Acid Transporter-1 and Boronophenylalanine-Based Boron Neutron Capture Therapy of Human Brain Tumors  

Science Journals Connector (OSTI)

...nebulizer, quartz spray chamber, and nickel cones. Calibration used matrix-matched aqueous standards prepared from boron-10-enriched boric acid. Standards and specimens to be assayed were diluted with an aqueous solution containing 2 butanol...

Allah Detta and Garth S. Cruickshank

2009-03-01T23:59:59.000Z

108

Scattering of Fast Neutrons by Boron  

Science Journals Connector (OSTI)

The cross section of boron for the scattering of fast neutrons through angles greater than 30° was measured at neutron energies between 0.2 and 3 Mev.

H. H. Barschall; M. E. Battat; W. C. Bright

1946-10-01T23:59:59.000Z

109

Computational aspects of treatment planning for neutron capture therapy  

E-Print Network (OSTI)

Boron Neutron Capture Therapy (BNCT) is a biochemically targeted form of binary radiation therapy that has the potential to deliver radiation to cancers with cellular dose selectivity. Accurate and efficient treatment ...

Albritton, James Raymond, 1977-

2010-01-01T23:59:59.000Z

110

“Sequential” Boron Neutron Capture Therapy (BNCT): A Novel Approach to BNCT for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model  

SciTech Connect

In the present study we evaluated the therapeutic effect and/or potential radiotoxicity of the novel “Tandem” Boron Neutron Capture Therapy (T-BNCT) for the treatment of oral cancer in the hamster cheek pouch model at RA-3 Nuclear Reactor. Two groups of animals were treated with “Tandem BNCT”, i.e. BNCT mediated by boronophenylalanine (BPA) followed by BNCT mediated by sodium decahydrodecaborate (GB-10) either 24 h (T-24h-BNCT) or 48 h (T-48h-BNCT) later. A total tumor dose-matched single application of BNCT mediated by BPA and GB-10 administered jointly [(BPA + GB-10)-BNCT] was administered to an additional group of animals. At 28 days post-treatment, T-24h-BNCT and T-48h-BNCT induced, respectively, overall tumor control (OTC) of 95% and 91%, with no statistically significant differences between protocols. Tumor response for the single application of (BPA + GB-10)-BNCT was 75%, significantly lower than for T-BNCT. The T-BNCT protocols and (BPA + GB-10)-BNCT induced reversible mucositis in dose-limiting precancerous tissue around treated tumors, reaching Grade 3/4 mucositis in 47% and 60% of the animals respectively. No normal tissue radiotoxicity was associated to tumor control for any of the protocols. “Tandem” BNCT enhances tumor control in oral cancer and reduces or, at worst, does not increase, mucositis in dose-limiting precancerous tissue.

Ana J. Molinari; Emiliano C. C. Pozzi; Andrea Monti Hughes; Elisa M. Heber; Marcela A. Garabalino; Silvia I. Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; David W. Nigg; Jorge Quintana; Gustavo A. Santa Cruz; Veronica A. Trivillin; Amanda E. Schwint

2011-04-01T23:59:59.000Z

111

The potential of transferrin-pendant-type polyethyleneglycol liposomes encapsulating decahydrodecaborate-{sup 1}B (GB-10) as {sup 1}B-carriers for boron neutron capture therapy  

SciTech Connect

Purpose: To evaluate GB-10-encapsulating transferrin (TF)-pendant-type polyethyleneglycol (PEG) liposomes as tumor-targeting {sup 1}B-carriers for boron neutron capture therapy. Methods and Materials: A free mercaptoundecahydrododecaborate-{sup 1}B (BSH) or decahydrodecaborate-{sup 1}B (GB-10) solution, bare liposomes, PEG liposomes, or TF-PEG liposomes were injected into SCC VII tumor-bearing mice, and {sup 1}B concentrations in the tumors and normal tissues were measured by {gamma}-ray spectrometry. Meanwhile, tumor-bearing mice were continuously given 5-bromo-2'-deoxyuridine (BrdU) to label all intratumor proliferating cells, then injected with these {sup 1}B-carriers containing BSH or GB-10 in the same manner. Right after thermal neutron irradiation, the response of quiescent (Q) cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for BrdU. The frequency in the total tumor cells was determined from the BrdU nontreated tumors. Results: Transferrin-PEG liposomes showed a prolonged retention in blood circulation, low uptake by reticuloendothelial system, and the most enhanced accumulation of {sup 1}B in solid tumors. In general, the enhancing effects were significantly greater in total cells than Q cells. In both cells, the enhancing effects of GB-10-containing {sup 1}B-carriers were significantly greater than BSH-containing {sup 1}B-carriers, whether loaded in free solution or liposomes. In both cells, whether BSH or GB-10 was employed, the greatest enhancing effect was observed with TF-PEG liposomes followed in decreasing order by PEG liposomes, bare liposomes, and free BSH or GB-10 solution. In Q cells, the decrease was remarkable between PEG and bare liposomes. Conclusions: In terms of biodistribution characteristics and tumor cell-killing effect as a whole, including Q cells, GB-10 TF-PEG liposomes were regarded as promising {sup 1}B-carriers.

Masunaga, Shin-ichiro [Particle Radiation Oncology Research Laboratory, Kyoto University, Kumatori, Osaka (Japan)]. E-mail: smasuna@rri.kyoto-u.ac.jp; Kasaoka, Satoshi [Laboratory of Pharmaceutics, Faculty of Pharmaceutical Sciences, Hiroshima International University, Hiroshima (Japan); Maruyama, Kazuo [Department of Pharmaceutics, Teikyo University, Kanagawa (Japan); Nigg, David [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States); Sakurai, Yoshinori [Department of Physics, Faculty of Medicine, Sapporo Medical University, Sapporo (Japan); Nagata, Kenji [Particle Radiation Oncology Research Laboratory, Kyoto University, Kumatori, Osaka (Japan); Suzuki, Minoru [Particle Radiation Oncology Research Laboratory, Kyoto University, Kumatori, Osaka (Japan); Kinashi, Yuko [Division of Radiation Safety, Kyoto University, Kumatori, Osaka (Japan); Maruhashi, Akira [Division of Radiation Life Science, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan); Ono, Koji [Particle Radiation Oncology Research Laboratory, Kyoto University, Kumatori, Osaka (Japan)

2006-12-01T23:59:59.000Z

112

L-Boronophenylalanine-Mediated Boron Neutron Capture Therapy for Malignant Glioma Progressing After External Beam Radiation Therapy: A Phase I Study  

SciTech Connect

Purpose: To investigate the safety of boronophenylalanine-mediated boron neutron capture therapy (BNCT) in the treatment of malignant gliomas that progress after surgery and conventional external beam radiation therapy. Methods and Materials: Adult patients who had histologically confirmed malignant glioma that had progressed after surgery and external beam radiotherapy were eligible for this Phase I study, provided that >6 months had elapsed from the last date of radiation therapy. The first 10 patients received a fixed dose, 290 mg/kg, of L-boronophenylalanine-fructose (L-BPA-F) as a 2-hour infusion before neutron irradiation, and the remaining patients were treated with escalating doses of L-BPA-F, either 350 mg/kg, 400 mg/kg, or 450 mg/kg, using 3 patients on each dose level. Adverse effects were assessed using National Cancer Institute Common Toxicity Criteria version 2.0. Results: Twenty-two patients entered the study. Twenty subjects had glioblastoma, and 2 patients had anaplastic astrocytoma, and the median cumulative dose of prior external beam radiotherapy was 59.4 Gy. The maximally tolerated L-BPA-F dose was reached at the 450 mg/kg level, where 4 of 6 patients treated had a grade 3 adverse event. Patients who were given >290 mg/kg of L-BPA-F received a higher estimated average planning target volume dose than those who received 290 mg/kg (median, 36 vs. 31 Gy [W, i.e., a weighted dose]; p = 0.018). The median survival time following BNCT was 7 months. Conclusions: BNCT administered with an L-BPA-F dose of up to 400 mg/kg as a 2-hour infusion is feasible in the treatment of malignant gliomas that recur after conventional radiation therapy.

Kankaanranta, Leena [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Seppaelae, Tiina; Koivunoro, Hanna [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Department of Physics, University of Helsinki, Helsinki (Finland); Boneca Corporation, Helsinki (Finland); Vaelimaeki, Petteri [Department of Physics, University of Helsinki, Helsinki (Finland); Boneca Corporation, Helsinki (Finland); Beule, Annette [HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Collan, Juhani [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Kortesniemi, Mika [HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Uusi-Simola, Jouni [Department of Physics, University of Helsinki, Helsinki (Finland); HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Kotiluoto, Petri; Auterinen, Iiro; Seren, Tom [VTT Technical Research Centre of Finland, Espoo (Finland); Paetau, Anders [Department of Pathology, Helsinki University Central Hospital, Helsinki (Finland); Saarilahti, Kauko [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Savolainen, Sauli [Department of Physics, University of Helsinki, Helsinki (Finland); HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Joensuu, Heikki, E-mail: heikki.joensuu@hus.f [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland)

2011-06-01T23:59:59.000Z

113

Indication of boron neutron capture therapy based on 18F-labeled BPA positron emission tomography of individual patients: New indications and possibility for other brain malignancies  

Science Journals Connector (OSTI)

...therapy (BNCT) is cell selective particle irradiation based upon the nuclear reaction that occur when non-radioactive boron-10 (10B) is irradiated with low energy neutrons to produce high energy alpha particles (10B[n,alpha] 7Li). In...

Shinji Kawabata; Kyoko Iida; Shin-Ichi Miyatake; Naosuke Nonoguchi; Minoru Miyashita; Toshihiko Kuroiwa; Yoshio Imahori; Koji Ono

2007-10-01T23:59:59.000Z

114

Tumor blood vessel "normalization" improves the therapeutic efficacy of boron neutron capture therapy (BNCT) in experimental oral cancer  

SciTech Connect

We previously demonstrated the efficacy of BNCT mediated by boronophenylalanine (BPA) to treat tumors in a hamster cheek pouch model of oral cancer with no normal tissue radiotoxicity and moderate, albeit reversible, mucositis in precancerous tissue around treated tumors. It is known that boron targeting of the largest possible proportion of tumor cells contributes to the success of BNCT and that tumor blood vessel normalization improves drug delivery to the tumor. Within this context, the aim of the present study was to evaluate the effect of blood vessel normalization on the therapeutic efficacy and potential radiotoxicity of BNCT in the hamster cheek pouch model of oral cancer.

D. W. Nigg

2012-01-01T23:59:59.000Z

115

Tandem Accelerator with Vacuum Insulation for Boron-Neutron-Capture Therapy and Detection of Explosives by Resonance Absorption of ?-Rays  

Science Journals Connector (OSTI)

The status of the design work on an electrostatic tandem-accelerator with vacuum insulation for 2.5 MeV protons and ... neutron therapy and the detection of explosives by nuclear-resonance absorption of ?-rays.

G. I. Dimov; Yu. I. Bel'chenko; G. S. Krainov; R. A. Salimov…

2003-02-01T23:59:59.000Z

116

Carrier doping into boron nanobelts by neutron transmutation  

SciTech Connect

We report the effects of a neutron-capture reaction of isotope {sup 10}B on the structure and electrical transport of {sup 10}B-enriched single-crystalline boron nanobelts. Partial amorphization, particularly at the surface of the nanobelt, was observed after thermal neutron irradiation with a dose of 2x10{sup 19} cm{sup -2}. Carrier doping into the nanobelts by neutron transmutation is expected after postannealing. The change in conductance is discussed based on the distribution of localized states in the band gap of {alpha}-tetragonal boron.

Kirihara, Kazuhiro; Shimizu, Yoshiki; Sasaki, Takeshi; Koshizaki, Naoto [Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565 (Japan); Yamada, Yoichi [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Esaka, Fumitaka [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Yamamoto, Hiroyuki; Shamoto, Shin-ichi [Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195 (Japan); Kimura, Kaoru [Department of Advanced Materials Science, The University of Tokyo, Kashiwa, Chiba 277-8561 (Japan)

2010-11-22T23:59:59.000Z

117

Boron Neutron Capture Therapty (BNCT) in an Oral Precancer Model: Therapeutic Benefits and Potential Toxicity of a Double Application of BNCT with a Six-Week Interval  

SciTech Connect

Given the clinical relevance of locoregional recurrences in head and neck cancer, we developed a novel experimental model of premalignant tissue in the hamster cheek pouch for long-term studies and demonstrated the partial inhibitory effect of a single application of Boron Neutron Capture Therapy (BNCT) on tumor development from premalignant tissue. The aim of the present study was to evaluate the effect of a double application of BNCT with a 6 week interval in terms of inhibitory effect on tumor development, toxicity and DNA synthesis. We performed a double application, 6 weeks apart, of (1) BNCT mediated by boronophenylalanine (BPA-BNCT); (2) BNCT mediated by the combined application of decahydrodecaborate (GB-10) and BPA [(GB-10 + BPA)-BNCT] or (3) beam-only, at RA-3 nuclear reactor and followed the animals for 8 months. The control group was cancerized and sham-irradiated. BPA-BNCT, (GB- 10 + BPA)-BNCT and beam-only induced a reduction in tumor development from premalignant tissue that persisted until 8, 3, and 2 months respectively. An early maximum inhibition of 100% was observed for all 3 protocols. No normal tissue radiotoxicity was detected. Reversible mucositis was observed in premalignant tissue, peaking at 1 week and resolving by the third week after each irradiation. Mucositis after the second application was not exacerbated by the first application. DNA synthesis was significantly reduced in premalignant tissue 8 months post-BNCT. A double application of BPA-BNCT and (GB-10 + BPA)-BNCT, 6 weeks apart, could be used therapeutically at no additional cost in terms of radiotoxicity in normal and dose-limiting tissues.

Andrea Monti Hughes; Emiliano C.C. Pozzi; Elisa M. Heber; Silvia Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; Ana J. Molinari; Marcela A. Garabalino; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

2011-11-01T23:59:59.000Z

118

High-power electron beam tests of a liquid-lithium target and characterization study of 7Li(p,n) near-threshold neutrons for accelerator-based boron neutron capture therapy  

Science Journals Connector (OSTI)

Abstract A compact Liquid-Lithium Target (LiLiT) was built and tested with a high-power electron gun at Soreq Nuclear Research Center (SNRC). The target is intended to demonstrate liquid-lithium target capabilities to constitute an accelerator-based intense neutron source for Boron Neutron Capture Therapy (BNCT) in hospitals. The lithium target will produce neutrons through the 7Li(p,n)7Be reaction and it will overcome the major problem of removing the thermal power >5 kW generated by high-intensity proton beams, necessary for sufficient therapeutic neutron flux. In preliminary experiments liquid lithium was flown through the target loop and generated a stable jet on the concave supporting wall. Electron beam irradiation demonstrated that the liquid-lithium target can dissipate electron power densities of more than 4 kW/cm2 and volumetric power density around 2 MW/cm3 at a lithium flow of ~4 m/s, while maintaining stable temperature and vacuum conditions. These power densities correspond to a narrow (?=~2 mm) 1.91 MeV, 3 mA proton beam. A high-intensity proton beam irradiation (1.91–2.5 MeV, 2 mA) is being commissioned at the SARAF (Soreq Applied Research Accelerator Facility) superconducting linear accelerator. In order to determine the conditions of LiLiT proton irradiation for BNCT and to tailor the neutron energy spectrum, a characterization of near threshold (~1.91 MeV) 7Li(p,n) neutrons is in progress based on Monte-Carlo (MCNP and Geant4) simulation and on low-intensity experiments with solid LiF targets. In-phantom dosimetry measurements are performed using special designed dosimeters based on CR-39 track detectors.

S. Halfon; M. Paul; A. Arenshtam; D. Berkovits; D. Cohen; I. Eliyahu; D. Kijel; I. Mardor; I. Silverman

2014-01-01T23:59:59.000Z

119

Recent advances in neutron capture therapy (NCT)  

SciTech Connect

The application of the /sup 10/B(n,..cap alpha..)/sup 7/Li reaction to cancer radiotherapy (Neutron Capture therapy, or NCT) has intrigued investigators since the discovery of the neutron. This paper briefly summarizes data describing recently developed boronated compounds with evident tumor specificity and extended biological half-lives. The implication of these compounds to NCT is evaluated in terms of Therapeutic Gain (TG). The optimization of NCT using band-pass filtered beams is described, again in terms of TG, and irradiation times with these less intense beams are estimated. 24 refs., 3 figs., 3 tabs.

Fairchild, R.G.

1985-01-01T23:59:59.000Z

120

Comparison of doses to normal brain in patients treated with boron neuron capture therapy at Brookhaven National Laboratory and MIT  

E-Print Network (OSTI)

A number of boron neutron capture therapy (BNCT) clinical trials are currently underway around the world. Due to the small number of patients at each of the individual centers, it is desirable to pool the clinical data ...

Turcotte, Julie Catherine

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Quantitative Imaging and Microlocalization of Boron-10 in Brain Tumors and Infiltrating Tumor Cells by SIMS Ion Microscopy: Relevance to Neutron Capture Therapy  

Science Journals Connector (OSTI)

...Imaging and Microlocalization of Boron-10 in Brain Tumors and Infiltrating...on the selective accumulation of boron-10 in tumor cells relative to the contiguous...evaluate the microdistribution of boron-10 from p-boronophenylalanine (BPA...

Duane R. Smith; Subhash Chandra; Rolf F. Barth; Weilian Yang; Darrel D. Joel; Jeffrey A. Coderre

2001-11-15T23:59:59.000Z

122

Neutron capture therapy at the MEPhI reactor  

Science Journals Connector (OSTI)

The article discusses the results of the creation and development of the irradiation base for Neutron Capture Therapy (NCT) at the MEPhI Reactor, development and studies of boron- and gadolinium-containing compounds, and presents the results of pre-clinical NCT studies in large laboratory animals â?? dogs with spontaneous melanoma.

K.N. Zaitsev; A.A. Portnov; O.V. Mishcherina; V.N. Kulakov; V.F. Khokhlov; I.N. Sheino; V.V. Meshcherikova; V.N. Mitin; N.G. Kozlovskaya; I.A. Shikunova

2004-01-01T23:59:59.000Z

123

Neutron detection using boron gallium nitride semiconductor material  

SciTech Connect

In this study, we developed a new neutron-detection device using a boron gallium nitride (BGaN) semiconductor in which the B atom acts as a neutron converter. BGaN and gallium nitride (GaN) samples were grown by metal organic vapor phase epitaxy, and their radiation detection properties were evaluated. GaN exhibited good sensitivity to ?-rays but poor sensitivity to ?-rays. Moreover, we confirmed that electrons were generated in the depletion layer under neutron irradiation. This resulted in a neutron-detection signal after ?-rays were generated by the capture of neutrons by the B atoms. These results prove that BGaN is useful as a neutron-detecting semiconductor material.

Atsumi, Katsuhiro [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Inoue, Yoku; Nakano, Takayuki, E-mail: ttnakan@ipc.shizuoka.ac.jp [Department of Electrical and Materials Science, Graduate School of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Mimura, Hidenori; Aoki, Toru [Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011 (Japan)

2014-03-01T23:59:59.000Z

124

Uranium-loaded apoferritin with antibodies attached: molecular design for uranium neutron-capture therapy  

Science Journals Connector (OSTI)

...Molecular design for uranium neutron-capture therapy (cancer/immunotherapy...methodology for cancer therapy. Boron...system using uranium, as described...800 to =400 uranium atoms per apoferritin...uranyl ions were depleted, and loading...

J F Hainfeld

1992-01-01T23:59:59.000Z

125

Boron neutron capture therapy (BNCT) for liver metastasis in an experimental model: dose–response at five-week follow-up based on retrospective dose assessment in individual rats  

SciTech Connect

Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. Employing an experimental model of liver metastases in rats, we recently demonstrated that BNCT mediated by boronophenylalanine (BPA-BNCT) at 13 Gy prescribed to tumor is therapeutically useful at 3-week follow-up. The aim of the present study was to evaluate dose–response at 5-week follow-up, based on retrospective dose assessment in individual rats. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA-BNCT (n = 19), Beam only (n = 8) and Sham (n = 7) (matched manipulation, no treatment). For each rat, neutron flux was measured in situ and boron content was measured in a pre-irradiation blood sample for retrospective individual dose assessment. For statistical analysis (ANOVA), individual data for the BPA-BNCT group were pooled according to absorbed tumor dose, BPA-BNCT I: 4.5–8.9 Gy and BPA-BNCT II: 9.2–16 Gy. At 5 weeks post-irradiation, the tumor surface area post-treatment/pre-treatment ratio was 12.2 +/- 6.6 for Sham, 7.8 +/- 4.1 for Beam only, 4.4 +/- 5.6 for BPA-BNCT I and 0.45 +/- 0.20 for BPA-BNCT II; tumor nodule weight was 750 +/- 480 mg for Sham, 960 +/- 620 mg for Beam only, 380 +/- 720 mg for BPA-BNCT I and 7.3 +/- 5.9 mg for BPA-BNCT II. The BPA-BNCT II group exhibited statistically significant tumor control with no contributory liver toxicity. Potential threshold doses for tumor response and significant tumor control were established at 6.1 and 9.2 Gy, respectively.

Emiliano C. C. Pozzi; Veronica A. Trivilin; Lucas L. Colombo; Andrea Monti Hughes; Silvia I. Thorp; Jorge E. Cardoso; Marcel A. Garabalino; Ana J. Molinari; Elisa M. Heber; Paula Curotto; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; David W. Nigg; Amanda E. Schwint

2013-11-01T23:59:59.000Z

126

Neutron capture cross sections for neutron-rich isotopes  

Science Journals Connector (OSTI)

Average continuum (Hauser-Feshbach) and resonance (Breit-Wigner) neutron capture rates for neutron-rich isotopes, determined on the basis of...

B. Leist; W. Ziegert; M. Wiescher…

1985-01-01T23:59:59.000Z

127

Boron-Lined Neutron Detector Measurements  

SciTech Connect

PNNL-18938 Revision Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. Reported here are the results of tests of a newly designed boron-lined proportional counter option. This testing measured the neutron detection efficiency and gamma ray rejection capabilities of two successive prototypes of a system manufactured by GE Reuter Stokes.

Lintereur, Azaree T.; Kouzes, Richard T.; Ely, James H.; Erikson, Luke E.; Siciliano, Edward R.; Woodring, Mitchell L.

2010-03-07T23:59:59.000Z

128

Boron-Lined Neutron Detector Measurements  

SciTech Connect

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. Reported here are the results of tests of a newly designed boron-lined proportional counter option. This testing measured the neutron detection efficiency and gamma ray rejection capabilities of a system manufactured by Reuter Stokes.

Lintereur, Azaree T.; Kouzes, Richard T.; Ely, James H.; Erikson, Luke E.; Siciliano, Edward R.

2009-11-02T23:59:59.000Z

129

High Resolution Quantitative Auto-Radiography to determine microscopic distributions of B-10 in neutron capture therapy  

E-Print Network (OSTI)

The success of Boron Neutron Capture Therapy (BNCT) is heavily dependent on the microscopic distribution of B-10 in tissue. High Resolution Quantitative Auto-Radiography (HRQAR) is a potentially valuable analytical tool ...

Harris, Thomas C. (Thomas Cameron)

2006-01-01T23:59:59.000Z

130

Synthesis and Evaluation of Amine Reactive Carboranyl Derivatives for Application to Boron-10 Containing Polymers  

Science Journals Connector (OSTI)

The use of monoclonal antibodies to selectively deliver boron-10 to cancer cells for boron neutron capture ... of boronated antibodies is the high concentrations of boron-10 required in the tumor tissue (e.g ... ...

D. S. Wilbur; D. K. Hamlin; R. R. Srivastava…

1993-01-01T23:59:59.000Z

131

Neutron detectors comprising ultra-thin layers of boron powder  

SciTech Connect

High-efficiency neutron detector substrate assemblies comprising a first conductive substrate, wherein a first side of the substrate is in direct contact with a first layer of a powder material having a thickness of from about 50 nm to about 250 nm and comprising .sup.10boron, .sup.10boron carbide or combinations thereof, and wherein a conductive material is in proximity to the first layer of powder material; and processes of making said neutron detector substrate assemblies.

Wang, Zhehul; Morris, Christopher

2013-07-23T23:59:59.000Z

132

Introduction to Neutron Coincidence Counter Design Based on Boron-10  

SciTech Connect

The Department of Energy Office of Nonproliferation Policy (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is ultimately to design, build and demonstrate a boron-lined proportional tube based alternative system in the configuration of a coincidence counter. This report, providing background information for this project, is the deliverable under Task 1 of the project.

Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.

2012-01-22T23:59:59.000Z

133

A toolkit for epithermal neutron beam characterisation in BNCT  

Science Journals Connector (OSTI)

......beams used in boron neutron capture...of different isotopes irradiated both...in-phantom for determination of the neutron...INTRODUCTION In boron neutron capture...of different isotopes irradiated both...in-phantom for determination of the neutron...Body Burden Boron Neutron Capture......

Iiro Auterinen; Tom Serén; Jouni Uusi-Simola; Antti Kosunen; Sauli Savolainen

2004-08-01T23:59:59.000Z

134

Vascular endothelial growth factor selectively targets boronated dendrimers to tumor vasculature  

Science Journals Connector (OSTI)

...delivery|Near-IR imaging| Introduction Boron neutron capture therapy (BNCT) is based on the selective delivery of boron-10 (10B) to tumor cells (1, 2). Following irradiation with low-energy neutrons, nuclear capture and fission reactions...

Marina V. Backer; Timur I. Gaynutdinov; Vimal Patel; Achintya K. Bandyopadhyaya; B.T.S. Thirumamagal; Werner Tjarks; Rolf F. Barth; Kevin Claffey; Joseph M. Backer

2005-09-01T23:59:59.000Z

135

Uranium Neutron Coincidence Collar Model Utilizing Boron-10 Lined Tubes  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report, providing results for model development of Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) designs, is a deliverable under Task 2 of the project.

Rogers, Jeremy L.; Ely, James H.; Kouzes, Richard T.; Lintereur, Azaree T.; Siciliano, Edward R.

2012-09-18T23:59:59.000Z

136

Biodistribution of Boron in Dogs with Spontaneous Intracranial Tumors following Borocaptate Sodium Administration  

Science Journals Connector (OSTI)

...pharmacokinetics Boron Neutron Capture Therapy...for boron neutron capture therapy...realistic spectrum of data and...with a high neutron capture cross-section...resulting thermal neutron capture...high LET fission particles...linear energy transfer...anesthesia (induced and main...

Susan L. Kraft; Patrick R. Gavin; Charles W. Leathers; Constance E. DeHaan; William F. Bauer; David L. Miller; Ronald V. Dorn III; and Merle L. Griebenow

1994-03-01T23:59:59.000Z

137

Boron-copper neutron absorbing material and method of preparation  

DOE Patents (OSTI)

A composite, copper clad neutron absorbing material is comprised of copper powder and boron powder enriched with boron 10. The boron 10 content can reach over 30 percent by volume, permitting a very high level of neutron absorption. The copper clad product is also capable of being reduced to a thickness of 0.05 to 0.06 inches and curved to a radius of 2 to 3 inches, and can resist temperatures of 900.degree. C. A method of preparing the material includes the steps of compacting a boron-copper powder mixture and placing it in a copper cladding, restraining the clad assembly in a steel frame while it is hot rolled at 900.degree. C. with cross rolling, and removing the steel frame and further rolling the clad assembly at 650.degree. C. An additional sheet of copper can be soldered onto the clad assembly so that the finished sheet can be cold formed into curved shapes.

Wiencek, Thomas C. (Bolingbrook, IL); Domagala, Robert F. (Indian Head Park, IL); Thresh, Henry (Palos Hts., IL)

1991-01-01T23:59:59.000Z

138

Neutron halo effect on direct neutron capture and photodisintegration  

Science Journals Connector (OSTI)

A novel effect of the neutron halo formation is presented for the direct radiative neutron capture where a p-wave neutron is captured into an s orbit with neutron halo by emitting an E1 ? ray. As an example, an enormous enhancement is demonstrated for the cross section of C12(n,?)13C(1/2+) at low energy in excellent agreement with a recent experiment. The S factor of the final state is evaluated. The inverse process, i.e., photo disintegration is discussed for an example of Be11. A sharp but nonresonant peak near the threshold is obtained as a result of the neutron halo in its anomalous ground state.

T. Otsuka; M. Ishihara; N. Fukunishi; T. Nakamura; M. Yokoyama

1994-05-01T23:59:59.000Z

139

E-Print Network 3.0 - accelerator-based boron neutron Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

University Collection: Materials Science ; Physics 46 A novel solid-state self powered neutron detector Nicholas LiCausi*a Summary: . For the nuclear physics and neutron boron...

140

Neutron capture in laser-fusion pellets  

Science Journals Connector (OSTI)

Investigating the feasibility of obtaining slow neutron fluencies sufficient for multiple-capture nucleosynthesis, we have applied a Monte Carlo technique to determine the moderation of neutrons in a superdense laser-energized fusion pellet. We studied pellets of varying chemical composition and structure ranging in size from ?R?1 to 50 g/cm2 and found our results to be rather insensitive to the parametrization of the hydrodynamic motion. That is, the neutron spectra were largely unaffected by reasonable variations of peak density, time of disassembly, and shape of the density profile. A useful method of improving the ratio of moderated to unmoderated neutrons was to dilute the thermonuclear fuel with hydrogen and/or the addition of a beryllium reflector. We also calculated the ratio of fission, neutron capture, and (n, p) reactions in pellets seeded with traces of U238 target material.NUCLEAR REACTIONS Calculated neutron fluxes and neutron-nucleus reactions for parametrized thermonuclear explosions of H2H3 and H2H2 laser-fusion pellets with moderators and target material.

John Henley and Heiner W. Meldner

1975-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Boron-Lined Multitube Neutron Proportional Counter Test  

SciTech Connect

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. These technologies are: 1) Boron trifluoride (BF3)-filled proportional counters, 2) Boron-lined proportional counters, 3) Lithium-loaded glass fibers, and 4) Coated non-scintillating plastic fibers. In addition, a few other companies have detector technologies that might be competitive in the near term as an alternative technology. Reported here are the results of tests of a boron-lined, “multitube” proportional counter manufactured by Centronic Ltd. (Surry, U.K. and Houston, TX). This testing measured the required performance for neutron detection efficiency and gamma-ray rejection capabilities of the detector.

Woodring, Mitchell L.; Ely, James H.; Kouzes, Richard T.; Stromswold, David C.

2010-09-07T23:59:59.000Z

142

Boronated porhyrins and methods for their use  

DOE Patents (OSTI)

The present invention covers boronated porphyrins containing multiple carborane cages which selectively accumulate in neoplastic tissue within the irradiation volume and thus can be used in cancer therapies such as boron neutron capture therapy and photodynamic therapy. 3 figs.

Miura, M.; Shelnutt, J.A.; Slatkin, D.N.

1999-03-02T23:59:59.000Z

143

Boronated porhyrins and methods for their use  

DOE Patents (OSTI)

The present invention covers boronated porphyrins containing multiple carborane cages which selectively accumulate in neoplastic tissue within the irradiation volume and thus can be used in cancer therapies such as boron neutron capture therapy and photodynamic therapy.

Miura, Michiko (Hampton Bays, NY); Shelnutt, John A. (Tijeras, NM); Slatkin, Daniel N. (Southhold, NY)

1999-03-02T23:59:59.000Z

144

Resonance Neutron Capture in Nb93  

Science Journals Connector (OSTI)

Spectra from radiative capture in S- and P-wave resonances in Nb93 have been compared. Differences in these spectra are interpreted to indicate the presence of sizable two-particle—one-hole components in the capturing states. S-wave intensities show no correlation with (d,p) intensities to the same final states, but P-wave intensities exhibit a significant correlation. Lack of a correlation with the initial-state reduced widths rules out an appreciable channel-capture effect in this experiment. The differences in S- and P-wave total radiation widths are discussed. Seven neutron-resonance spin assignments are made, based on the capture ?-ray spectra, and 11 new final states in Nb94 are observed and tabulated.

R. E. Chrien; K. Rimawi; J. B. Garg

1971-05-01T23:59:59.000Z

145

Neutron Captures in the r-Process  

E-Print Network (OSTI)

The r-process involves neutron-rich nuclei far off stability for which no experimental cross sections are known. Therefore, one has to rely on theory. The difficulties in the predictions are briefly addressed. To investigate the impact of altered rates, a comparison of r-process production in hot bubble models with largely varied rates is shown. Due to the (n,gamma)-(gamma,n) equilibrium established at the onset of the r-process, only late-time neutron captures are important which mainly modify the abundances around the third r-process peak.

T. Rauscher

2004-04-12T23:59:59.000Z

146

Thermal Neutron Capture y's (CapGam)  

DOE Data Explorer (OSTI)

The National Nuclear Data Center (NNDC) presents two tables showing energy and photon intensity with uncertainties of gamma rays as seen in thermal-neutron capture.  One table is organized in ascending order of gamma energy, and the second is organized by Z, A of the target. In the energy-ordered table the three strongest transitions are indicated in each case. The nuclide given is the target nucleus in the capture reaction. The gamma energies given are in keV. The gamma intensities given are relative to 100 for the strongest transition. %I? (per 100 n-captures) for the strongest transition is given, where known. All data are taken from the Evaluated Nuclear Structure Data File (ENSDF), a computer file of evaluated nuclear structure data and from the eXperimental Unevaluated Nuclear Data List (XUNDL). (Specialized Interface)

147

Three-dimensional boron particle loaded thermal neutron detector  

DOE Patents (OSTI)

Three-dimensional boron particle loaded thermal neutron detectors utilize neutron sensitive conversion materials in the form of nano-powders and micro-sized particles, as opposed to thin films, suspensions, paraffin, etc. More specifically, methods to infiltrate, intersperse and embed the neutron nano-powders to form two-dimensional and/or three-dimensional charge sensitive platforms are specified. The use of nano-powders enables conformal contact with the entire charge-collecting structure regardless of its shape or configuration.

Nikolic, Rebecca J.; Conway, Adam M.; Graff, Robert T.; Kuntz, Joshua D.; Reinhardt, Catherine; Voss, Lars F.; Cheung, Chin Li; Heineck, Daniel

2014-09-09T23:59:59.000Z

148

Predicting Boron-10 Concentrations in Normal Brain and GBM from Blood Measurements  

Science Journals Connector (OSTI)

In boron neutron capture therapy (BNCT), radiation dose delivered to the target and surrounding tissues is a complex function of neutron energies, fluxes, tissue compositions, boron concentrations and relative...

M. R. Palmer; C. Chuang; W. S. Kiger; P. M. Busse…

2001-01-01T23:59:59.000Z

149

Continuous Measurement of Boron-10 Concentration in Rabbit Brain Tissue and Blood Using Prompt Gamma-Ray Spectrometry  

Science Journals Connector (OSTI)

One of the important factors which influences the efficacy of boron neutron capture therapy (BNCT) in patients with malignant brain tumour is the boron-10 concentrations in tumours. The boron-10 concentration in ...

Yoshinobu Nakagawa; Tooru Kobayashi…

1992-01-01T23:59:59.000Z

150

Thermal neutron capture gamma-rays  

SciTech Connect

The energy and intensity of gamma rays as seen in thermal neutron capture are presented. Only those (n,..cap alpha..), E = thermal, reactions for which the residual nucleus mass number is greater than or equal to 45 are included. These correspond to evaluations published in Nuclear Data Sheets. The publication source data are contained in the Evaluated Nuclear Structure Data File (ENSDF). The data presented here do not involve any additional evaluation. Appendix I lists all the residual nuclides for which the data are included here. Appendix II gives a cumulated index to A-chain evaluations including the year of publication. The capture gamma ray data are given in two tables - the Table 1 is the list of all gamma rays seen in (n,..gamma..) reaction given in the order of increasing energy; the Table II lists the gamma rays according to the nuclide.

Tuli, J.K.

1983-01-01T23:59:59.000Z

151

Neutron degeneracy and plasma physics effects on radiative neutron captures in neutron star crust  

Science Journals Connector (OSTI)

We consider the astrophysical reaction rates for radiative neutron capture reactions (n,?) in the crust of a neutron star. The presence of degenerate neutrons at high densities (mainly in the inner crust) can drastically affect the reaction rates. Standard rates assuming a Maxwell-Boltzmann distribution for neutrons can underestimate the rates by several orders of magnitude. We derive simple analytical expressions for reaction rates at a variety of conditions with account for neutron degeneracy. We also discuss the plasma effects on the outgoing radiative transition channel in neutron radiative capture reactions and show that these effects can also increase the reaction rates by a few orders of magnitude. In addition, using detailed balance, we analyze the effects of neutron degeneracy and plasma physics on reverse (?,n) photodisintegration. We discuss the dependence of the reaction rates on temperature and neutron chemical potential and outline the efficiency of these reactions in the neutron star crust.

P. S. Shternin; M. Beard; M. Wiescher; D. G. Yakovlev

2012-07-24T23:59:59.000Z

152

Boron-Lined Straw-Tube Neutron Detector Test  

SciTech Connect

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. Reported here are the results of tests of a boron-lined proportional counter design variation. In the testing described here, the neutron detection efficiency and gamma ray rejection capabilities of a system manufactured by Proportional Technologies, Inc, was tested.

Kouzes, Richard T.; Ely, James H.; Stromswold, David C.

2010-08-07T23:59:59.000Z

153

Experimental evaluation of neutron performance in boron-doped low activation concrete  

Science Journals Connector (OSTI)

......concrete (LAC) without boron-doping exposed to reactor...and special limestone. Boron (0.8 wt.%) was introduced in the form of boron carbide. NaCl powder...counted twice to detect two isotopes, 97Zr and 95Zr. The...uncertainty in neutron spectra determination is independent from uncertainties......

T. Ogawa; M. N. Morev; T. Abe; T. Iimoto; T. Kosako; K. Kimura; M. Kinno

2010-06-01T23:59:59.000Z

154

Neutron capture therapy with deep tissue penetration using capillary neutron focusing  

DOE Patents (OSTI)

An improved method for delivering thermal neutrons to a subsurface cancer or tumor which has been first doped with a dopant having a high cross section for neutron capture. The improvement is the use of a guide tube in cooperation with a capillary neutron focusing apparatus, or neutron focusing lens, for directing neutrons to the tumor, and thereby avoiding damage to surrounding tissue.

Peurrung, Anthony J. (Richland, WA)

1997-01-01T23:59:59.000Z

155

Measurement of Thermal Neutron Flux in Photo-Neutron Source  

Science Journals Connector (OSTI)

The Photo-Neutron Source (PNS) project is a study ... design, simulation and construction an accelerator based neutron source for Boron Neutron Capture Therapy (BNCT). The system uses ... medical linear accelerat...

A. Taheri; A. Torkamani; A. Pazirandeh…

2013-01-01T23:59:59.000Z

156

Preliminary study of neutron absorption by concrete with boron carbide addition  

SciTech Connect

Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

Abdullah, Yusof, E-mail: yusofabd@nuclearmalaysia.gov.my; Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Ariffin, Fatin Nabilah Tajul; Ahmad, Sahrim [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Hamid, Roszilah [Department of Civil and Structural Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Mohamed, Abdul Aziz [College of Engineering, Universiti Tenaga National, Jalan Ikram-Uniten, 43000 Kajang, Selangor (Malaysia)

2014-02-12T23:59:59.000Z

157

Interaction of Neutrons with Matter  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is a binary radiotherapy modality used in treatment of brain lesions. First, the patient is injected with a tumor seeking drug containing a stable boron-10 nuclide that has a ...

Ervin B. Podgoršak

2014-01-01T23:59:59.000Z

158

Neutron Capture Gamma-Ray Libraries for Nuclear Applications  

SciTech Connect

The neutron capture reaction is useful in identifying and analyzing the gamma-ray spectrum from an unknown assembly as it gives unambiguous information on its composition. this can be done passively or actively where an external neutron source is used to probe an unknown assembly. There are known capture gamma-ray data gaps in the ENDF libraries used by transport codes for various nuclear applications. The Evaluated Gamma-ray Activation file (EGAF) is a new thermal neutron capture database of discrete line spectra and cross sections for over 260 isotopes that was developed as part of an IAEA Coordinated Research project. EGAF is being used to improve the capture gamma production in ENDF libraries. For medium to heavy nuclei the quasi continuum contribution to the gamma cascades is not experimentally resolved. The continuum contains up to 90% of all the decay energy and is modeled here with the statistical nuclear structure code DICEBOX. This code also provides a consistency check of the level scheme nuclear structure evaluation. The calculated continuum is of sufficient accuracy to include in the ENDF libraries. This analysis also determines new total thermal capture cross sections and provides an improved RIPL database. For higher energy neutron capture there is less experimental data available making benchmarking of the modeling codes more difficult. They are investigating the capture spectra from higher energy neutrons experimentally using surrogate reactions and modeling this with Hauser-Feshbach codes. This can then be used to benchmark CASINO, a version of DICEBOX modified for neutron capture at higher energy. This can be used to simulate spectra from neutron capture at incident neutron energies up to 20 MeV to improve the gamma-ray spectrum in neutron data libraries used for transport modeling of unknown assemblies.

Sleaford, B W; Firestone, R B; Summers, N; Escher, J; Hurst, A; Krticka, M; Basunia, S; Molnar, G; Belgya, T; Revay, Z; Choi, H D

2010-11-04T23:59:59.000Z

159

Sensitivity studies for the weak r process: neutron capture rates  

SciTech Connect

Rapid neutron capture nucleosynthesis involves thousands of nuclear species far from stability, whose nuclear properties need to be understood in order to accurately predict nucleosynthetic outcomes. Recently sensitivity studies have provided a deeper understanding of how the r process proceeds and have identified pieces of nuclear data of interest for further experimental or theoretical study. A key result of these studies has been to point out the importance of individual neutron capture rates in setting the final r-process abundance pattern for a ‘main’ (A ? 130 peak and above) r process. Here we examine neutron capture in the context of a ‘weak’ r process that forms primarily the A ? 80 r-process abundance peak. We identify the astrophysical conditions required to produce this peak region through weak r-processing and point out the neutron capture rates that most strongly influence the final abundance pattern.

Surman, R., E-mail: surmanr@union.edu [Department of Physics and Astronomy, Union College, Schenectady, NY 12308 (United States); Mumpower, M. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)] [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Sinclair, R.; Jones, K. L. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States)] [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Hix, W. R. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States) [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); McLaughlin, G. C. [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States)] [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States)

2014-04-15T23:59:59.000Z

160

Noninvasive in-vivo Detection of Boron-10 by Magnetic Resonance  

Science Journals Connector (OSTI)

One of the major problems associated with the successful clinical implementation of boron neutron capture therapy (BNCT), is the ability to determine boron-10 concentrations in the tumor and the surrounding...

Peter Bendel; Judith Zilberstein; Yoram Salomon…

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Neutron capture cross sections: from theory to experiments and back  

E-Print Network (OSTI)

The method for an experimental determination of the stellar enhancement factor for the cross section of the $^{151}$Sm$(n,\\gamma)$ reaction process is proposed. This study offered the pretext for an excursus on the interconnections between capture and dissociation reactions and the interplay between theory and experiments in the determination of neutron capture cross sections.

Alberto Mengoni

2005-01-31T23:59:59.000Z

162

Methods for boron delivery to mammalian tissue  

DOE Patents (OSTI)

Boron neutron capture therapy can be used to destroy tumors. This treatment modality is enhanced by delivering compounds to the tumor site where the compounds have high concentrations of boron, the boron compounds being encapsulated in the bilayer of a liposome or in the bilayer as well as the internal space of the liposomes. Preferred compounds, include carborane units with multiple boron atoms within the carborane cage structure. Liposomes with increased tumor specificity may also be used.

Hawthorne, M. Frederick (Encino, CA); Feaks, Debra A. (Los Angeles, CA); Shelly, Kenneth J. (Los Angeles, CA)

2003-01-01T23:59:59.000Z

163

Direct measurements of neutron capture on radioactive isotopes  

E-Print Network (OSTI)

We simulated the response of a 4p calorimetric g-detector array to decays of radioactive isotopes on the s-process path. The GEANT 3.21 simulation package was used. The main table contains estimates on the maximum sample size and required neutron flux based on the latest available neutron capture cross section at 30 keV. The results are intended to be used to estimate the feasibility of neutron capture measurements with 4p arrays using the time of flight technique.

A. Couture; R. Reifarth

2009-09-30T23:59:59.000Z

164

Neutron capture therapy with deep tissue penetration using capillary neutron focusing  

DOE Patents (OSTI)

An improved method is disclosed for delivering thermal neutrons to a subsurface cancer or tumor which has been first doped with a dopant having a high cross section for neutron capture. The improvement is the use of a guide tube in cooperation with a capillary neutron focusing apparatus, or neutron focusing lens, for directing neutrons to the tumor, and thereby avoiding damage to surrounding tissue. 1 fig.

Peurrung, A.J.

1997-08-19T23:59:59.000Z

165

Neutron capture of 26Mg at thermonuclear energies  

E-Print Network (OSTI)

The neutron capture cross section of 26Mg was measured relative to the known gold cross section at thermonuclear energies using the fast cyclic activation technique. The experiment was performed at the 3.75 MV Van-de-Graaff accelerator, Forschungszentrum Karlsruhe. The experimental capture cross section is the sum of resonant and direct contributions. For the resonance at E(n,lab) = 220 keV our new results are in disagreement with the data from Weigmann et al. An improved Maxwellian averaged capture cross section is derived from the new experimental data taking into account s- and p-wave capture and resonant contributions. The properties of so-called potential resonances which influence the p-wave neutron capture of 26}Mg are discussed in detail.

P. Mohr; H. Beer; H. Oberhummer; G. Staudt

1998-05-20T23:59:59.000Z

166

Short and long-term exposure of CNS cell lines to BPA-f a radiosensitizer for Boron Neutron Capture Therapy: safety dose evaluation by a battery of cytotoxicity tests  

Science Journals Connector (OSTI)

Despite the current clinical use of boronophenylalanine-fructose (BPA-f), as radiosensitizer, in BNCT application for brain tumors, still remains to be determined the safety dose of this agent. We evaluated the potential risk of primary BPA-f toxicity before neutronic irradiation at different concentrations (0–100 ?g Beq/ml) after short- and long-term exposure (4–48 h and 7–10 days), using a battery of tests (i.e. MTT assay, calcein-AM/Propidium Iodide staining, clonogenic test) in CNS cell models (D384 and SH-SY5Y), and non-neuronal primary human fibroblasts (F26). MTT data showed: (i) no cytotoxic effects after short-term exposure (4 h) to any of BPA-f concentrations tested in all cell models; (ii) dose- and time-dependent mitochondrial activity impairment in D384 and SH-SY5Y cells only (with 60% and 40% cell death in D384 and SH-SY5Y, respectively, after 48 h exposure to BPA-f 100 ?g Beq/ml). By Calcein-AM/PI staining, BPA-f treatment was specific toward SH-SY5Y cells only: a dose-dependent cell density reduction was observed, with a more pronounced effect after 48 h exposure (15–40% at doses ranging 20–100 ?g Beq/ml). Clonogenic data revealed dose-dependent decrease of cell proliferative capacity in all cell lines, still the SH-SY5Y cells were the most sensitive ones: the lowest dose (20 ?g Beq/ml) produced 90% cell decrease. These results indicate dose- and time-dependent cytotoxic effects of BPA-f, with CNS cells showing a lower tolerance compared to fibroblasts. Long-term exposure to BPA-f compromised the proliferative capacity regardless of cell model type (cell sensitivity being SH-SY5Y > D384 > F26). In short-time exposure, BPA-f exhibits a safe dosage up to 40 ?g Beq/ml for the viability of CNS cell lines.

U. De Simone; L. Manzo; C. Ferrari; J. Bakeine; C. Locatelli; T. Coccini

2013-01-01T23:59:59.000Z

167

Modelling boron-lined proportional counter response to neutrons  

Science Journals Connector (OSTI)

......of lithium. BF3 and boron-lined proportional...counters that employ 10B isotopes, the first in the gaseous...might be expected that boron-lined counters would...function of a typical boron-lined counter (2013...Koohi-Fayegh R. Determination of 4.43 MeV gamma-ray......

A. Shahri; N. Ghal-Eh; G. R. Etaati

2013-09-01T23:59:59.000Z

168

Boron-containing amino carboxylic acid compounds and uses thereof  

DOE Patents (OSTI)

Novel compounds which are useful for boron neutron capture therapy (BNCT) are disclosed. The compounds comprise a stable boron-containing group and an aminocycloalkane carboxylic acid group or a boronated acyclic hydrocarbon-linked amino carboxylic acid. Methods for synthesis of the compounds and for use of the compounds in BNCT are disclosed.

Kabalka, George W. (Knoxville, TN); Srivastava, Rajiv R. (Knoxville, TN)

2000-03-14T23:59:59.000Z

169

Radiative Neutron Capture on Carbon-14 in Effective Field Theory  

E-Print Network (OSTI)

The cross section for radiative capture of neutron on carbon-14 is calculated using the model-independent formalism of halo effective field theory. The dominant contribution from E1 transition is considered, and the cross section is expressed in terms of elastic scattering parameters of the effective range expansion. Contributions from both resonant and non-resonant interaction are calculated. Significant interference between these leads to a capture contribution that deviates from simple Breit-Wigner resonance form.

Gautam Rupak; Lakma Fernando; Akshay Vaghani

2012-04-19T23:59:59.000Z

170

Radiative Neutron Capture on Carbon-14 in Effective Field Theory  

E-Print Network (OSTI)

The cross section for radiative capture of neutron on carbon-14 is calculated using the model-independent formalism of halo effective field theory. The dominant contribution from E1 transition is considered, and the cross section is expressed in terms of elastic scattering parameters of the effective range expansion. Contributions from both resonant and non-resonant interaction are calculated. Significant interference between these leads to a capture contribution that deviates from simple Breit-Wigner resonance form.

Rupak, Gautam; Vaghani, Akshay

2012-01-01T23:59:59.000Z

171

Neutron capture and neutron-induced fission experiments on americium isotopes with DANCE  

SciTech Connect

Neutron capture cross section data on Am isotopes were measured using the Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory. The neutron capture cross section was determined for {sup 241}Am for neutron energies between thermal and 320 keV. Preliminary results were also obtained for {sup 243}Am for neutron energies between 35 eV and 200 keV. The results on concurrent neutron-induced fission and neutron-capture measurements on {sup 242m}Am will be presented, where the fission events were actively triggered during the experiments. In these experiments, the Parallel-Plate Avalanche Counter (PPAC) detector that surrounds the target located in the center of the DANCE array was used as a fission-tagging detector to separate (n,{gamma}) from (n,f) events. The first evidence of neutron capture on {sup 242m}Am in the resonance region in between 2 and 9 eV of the neutron energy was obtained.

Jandel, Marian [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

172

Neutron capture and neutron-induced fission experiments on americium isotopes with DANCE  

SciTech Connect

Neutron capture cross section data on Am isotopes were measured using the Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory. The neutron capture cross section was determined for {sup 241}Am for neutron energies between thermal and 320 keV. Preliminary results were also obtained for {sup 243}Am for neutron energies between 10 eV and 250 keV. The results on concurrent neutron-induced fission and neutron-capture measurements on {sup 242m}Am will be presented where the fission events were actively triggered during the experiments. In these experiments, a Parallel-Plate Avalanche Counter (PPAC) detector that surrounds the target located in the center of the DANCE array was used as a fission-tagging detector to separate (n,{gamma}) events from (n,f) events. The first direct observation of neutron capture on {sup 242m}Am in the resonance region in between 2 and 9 eV of the neutron energy was obtained.

Jandel, M.; Bredeweg, T. A.; Fowler, M. M.; Bond, E. M.; Couture, A.; Haight, R. C.; Keksis, A. L.; O'Donnell, J. M.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M. [Los Alamos National Laboratory, Los Alamos, NM, 87545 (United States); Stoyer, M. A.; Wu, C. Y.; Becker, J. A.; Haslett, R. J.; Henderson, R. A. [Lawrence Livermore National Laboratory, Livermore, CA, 94550 (United States)

2009-01-28T23:59:59.000Z

173

Continuum quasiparticle random phase approximation for astrophysical direct neutron capture reaction of neutron-rich nuclei  

E-Print Network (OSTI)

We formulate a many-body theory to calculate the cross section of direct radiative neutron capture reaction by means of the Hartree-Fock-Bogoliubov mean-field model and the continuum quasiparticle random phase approximation (QRPA). A focus is put on very neutron-rich nuclei and low-energy neutron kinetic energy in the range of O(1 keV) - O(1 MeV), relevant for the rapid neutron-capture process of nucleosynthesis. We begin with the photo-absorption cross section and the E1 strength function, then, in order to apply the reciprocity theorem, we decompose the cross section into partial cross sections corresponding to different channels of one- and two-neutron emission decays of photo-excited states. Numerical example is shown for the photo-absorption of $^{142}$Sn and the neutron capture of $^{141}$Sn.

Masayuki Matsuo

2014-10-31T23:59:59.000Z

174

Cubic boron nitride: a new prospective material for ultracold neutron application  

E-Print Network (OSTI)

For the first time, the neutron optical wall-potential of natural cubic boron nitride (cBN) was measured at the ultracold neutron (UCN) source of the research reactor TRIGA Mainz using the time-of-flight method (TOF). The samples investigated had a wall-potential of (305 +/- 15) neV. This value is in good agreement with the result extracted from neutron reflectometry data and theoretical expectations. Because of its high critical velocity for UCN and its good dielectric characteristics, cubic boron nitride coatings (isotopically enriched) will be useful for a number of applications in UCN experiments.

Sobolev, Yu; Borisov, Yu; Daum, M; Fresne, N du; Goeltl, L; Hampel, G; Heil, W; Knecht, A; Keunecke, M; Kratz, J V; Lang, T; Meister, M; Plonka-Spehr, Ch; Pokotilovski, Yu; Reichert, P; Schmidt, U; Krist, Th; Wiehl, N; Zenner, J

2009-01-01T23:59:59.000Z

175

Thermal neutron response of a boron-coated GEM detector via GEANT4 Monte Carlo code  

Science Journals Connector (OSTI)

Abstract In this work, we report the design configuration and the performance of the hybrid Gas Electron Multiplier (GEM) detector. In order to make the detector sensitive to thermal neutrons, the forward electrode of the GEM has been coated with the enriched boron-10 material, which works as a neutron converter. A total of 5×5 cm2 configuration of GEM has been used for thermal neutron studies. The response of the detector has been estimated via using GEANT4 MC code with two different physics lists. Using the QGSP_BIC_HP physics list, the neutron detection efficiency was determined to be about 3%, while with QGSP_BERT_HP physics list the efficiency was around 2.5%, at the incident thermal neutron energies of 25 meV. The higher response of the detector proves that GEM-coated with boron converter improves the efficiency for thermal neutrons detection.

M. Jamil; J.T. Rhee; H.G. Kim; Farzana Ahmad; Y.J. Jeon

2015-01-01T23:59:59.000Z

176

Thermal Neutron Capture for Nuclei A = 3 - 20  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermal Neutron Capture Evaluated Data for Nuclei A 3 - 20 Go to the Text Only below if you prefer to view the nuclides in a text list. 19Ne 20Ne 18F 19F 20F 15O 16O 17O 18O 19O...

177

Neutron Capture Measurements and Resonance Analysis of Dysprosium  

Science Journals Connector (OSTI)

Abstract The electron linear accelerator facility at the Rensselaer Polytechnic Institute was used to measure neutron capture yields of dysprosium with the time-of-flight method in the neutron energy region from 10 eV to 1 keV. The neutron capture experiments were made at a flight path length of 25.5 m with a 16-section NaI multiplicity detector. High purity isotopic samples of 161Dy, 162Dy, 163Dy, 164Dy as well as one natural dysprosium sample with thickness of 0.508 mm were used in this measurement. Resonance parameters were extracted from the data using simultaneous fit with the multilevel R-matrix Bayesian code SAMMY 8.0. New resonances are proposed, and other resonances previously identified in the literature have been revised. The present results are compared with other evaluated values of ENDF/B-VII.1 and JENDL 4.0.

Y.R. Kang; M.W. Lee; T.I. Ro; G.N. Kim; Y. Danon; D. Williams

2014-01-01T23:59:59.000Z

178

Proposed experiment to measure {gamma}-rays from the thermal neutron capture of gadolinium  

SciTech Connect

Gadolinium-157 ({sup 157}Gd) has the largest thermal neutron capture cross section among any stable nuclei. The thermal neutron capture yields {gamma}-ray cascade with total energy of about 8 MeV. Because of these characteristics, Gd is applied for the recent neutrino detectors. Here, we propose an experiment to measure the multiplicity and the angular correlation of {gamma}-rays from the Gd neutron capture. With these information, we expect the improved identification of the Gd neutron capture.

Yano, Takatomi; Ou, I.; Izumi, T.; Yamaguchi, R.; Mori, T.; Sakuda, M. [Department of Physics, Okayama University, Okayama, 700-8530 (Japan)

2012-11-12T23:59:59.000Z

179

Improved Neutron-Capture Element Abundances in Planetary N. C. SterlingA,I  

E-Print Network (OSTI)

Improved Neutron-Capture Element Abundances in Planetary Nebulae N. C. SterlingA,I , H. L of neutron(n)-capture elements that cannot be detected in asymptotic giant branch (AGB) stars. However Approximately half of the neutron(n)-capture elements (atomic number Z > 30) in the Universe are created by slow

Royer, Dana

180

Standard specification for boron-Based neutron absorbing material systems for use in nuclear spent fuel storage racks  

E-Print Network (OSTI)

1.1 This specification defines criteria for boron-based neutron absorbing material systems used in racks in a pool environment for storage of nuclear light water reactor (LWR) spent-fuel assemblies or disassembled components to maintain sub-criticality in the storage rack system. 1.2 Boron-based neutron absorbing material systems normally consist of metallic boron or a chemical compound containing boron (for example, boron carbide, B4C) supported by a matrix of aluminum, steel, or other materials. 1.3 In a boron-based absorber, neutron absorption occurs primarily by the boron-10 isotope that is present in natural boron to the extent of 18.3 ± 0.2 % by weight (depending upon the geological origin of the boron). Boron, enriched in boron-10 could also be used. 1.4 The materials systems described herein shall be functional – that is always be capable to maintain a B10 areal density such that subcriticality Keff <0.95 or Keff <0.98 or Keff < 1.0 depending on the design specification for the service...

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Estimation of Performance of an Active Well Coincidence Counter Equipped with Boron-Coated Straw Neutron Detectors - 13401  

SciTech Connect

He-3, a very rare isotope of natural helium gas, has ideal properties for the detection of thermal neutrons. As such it has become the standard material for neutron detectors and sees ubiquitous use within many radiometric applications that require neutron sensitivity. Until recently, there has been a fairly abundant supply of He-3. However, with the reduction in nuclear weapons, production of tritium ceased decades ago and the stockpile has largely decayed away, reducing the available He-3 supply to a small fraction of that needed for neutron detection. A suitable and rapidly-deployable replacement technology for neutron detectors must be found. Many potential replacement technologies are under active investigation and development. One broad class of technologies utilizes B-10 as a neutron capture medium in coatings on the internal surfaces of proportional detectors. A particular implementation of this sort of technology is the boron-coated 'straw' (BCS) detectors under development by Proportional Technologies, Inc. (PTi). This technology employs a coating of B-10 enriched boron carbide (B{sub 4}C) on the inside of narrow tubes, roughly 4 mm in diameter. A neutron counter (e.g. a slab, a well counter, or a large assay counter designed to accommodate 200 liter drums) could be constructed by distributing these narrow tubes throughout the polyethylene body of the counter. One type of neutron counter that is of particular importance to safeguards applications is the Active Well Coincidence Counter (AWCC), which is a Los Alamos design that traditionally employs 42 He-3 detectors. This is a very flexible design which can accurately assay small samples of uranium- and plutonium-bearing materials. Utilizing the MCNPX code and benchmarking against measurements where possible, the standard AWCC has been redesigned to utilize the BCS technology. Particular aspects of the counter performance include the single-neutron ('singles') detection efficiency and the time constant for the decrease in neutron population in the counter following a fission event (a.k.a. the die-away time). Results of the modeling and optimization are presented. (authors)

Young, B.M. [Canberra Industries, Inc., 800 Research Parkway, Meriden, CT 06450 (United States)] [Canberra Industries, Inc., 800 Research Parkway, Meriden, CT 06450 (United States); Lacy, J.L.; Athanasiades, A. [Proportional Technologies, Inc., 8022 El Rio Street, Houston, TX 77054 (United States)] [Proportional Technologies, Inc., 8022 El Rio Street, Houston, TX 77054 (United States)

2013-07-01T23:59:59.000Z

182

Solar Abundance of Elements from Neutron-Capture Cross Sections  

E-Print Network (OSTI)

Excess lightweight products of slow neutron capture in the photosphere, over the mass range of 25 to 207 amu, confirm the solar mass separation recorded by excess lightweight isotopes in the solar wind, over the mass range of 3 to 136 amu [Solar Abundance of the Elements, Meteoritics, volume 18, 1983, pages 209 to 222]. Both measurements show that major elements inside the Sun are Fe, O, Ni, Si and S, like those in rocky planets.

O. Manuel; W. A. Myers; Y. Singh; M. Pleess

2004-12-19T23:59:59.000Z

183

Experimental evaluation of neutron performance in boron-doped low activation concrete  

Science Journals Connector (OSTI)

......exposed to neutrons escaping...prediction of induced activity...Long-lived induced activity...capture of thermal and resonance neutrons by traces...neutrons in the spectrum. Consequently...monitored using a fission chamber was...resonance energy (E eff 6......

T. Ogawa; M. N. Morev; T. Abe; T. Iimoto; T. Kosako; K. Kimura; M. Kinno

2010-06-01T23:59:59.000Z

184

First Measurements of the Inclined Boron Layer Thermal-Neutron Detector for Reflectometry  

SciTech Connect

A prototype detector based on the inclined boron layer principle is introduced. For typical measurement conditions at the Liquids Reflectometer at the Spallation Neutron Source, its count rate capability is shown to be superior to that of the current detector by nearly two orders of magnitude.

Clonts, Lloyd G [ORNL; Crow, Lowell [ORNL; Van Vuure, Thorwald L [ORNL; Robertson, Lee [ORNL; Riedel, Richard A [ORNL; Richards, John D [ORNL; Cooper, Ronald G [ORNL; Remec, Igor [ORNL; Ankner, John Francis [ORNL; Browning, Jim [ORNL

2010-01-01T23:59:59.000Z

185

Toward a cancer therapy with boron-rich oligomeric phosphate diesters that target the cell nucleus  

Science Journals Connector (OSTI)

...agents that contain large numbers of boron-10 (10B) atoms and are readily taken...the capture of thermal neutrons by boron-10 ( 10 B) nuclei that have been selectively...agents that contain large numbers of boron-10 (10B) atoms and are readily...

Akira Nakanishi; Lufeng Guan; Robert R. Kane; Harumi Kasamatsu; M. Frederick Hawthorne

1999-01-01T23:59:59.000Z

186

Design and Simulation of a Boron-loaded Neutron Spectrometer  

E-Print Network (OSTI)

The measurement of the distribution of kinetic energy carried by neutron particles is of interest to the health physics and radiation protection industry. Neutron particle spectral fluence is essential to the calculation of absorbed dose, equivalent...

Martin, Thomas

2012-10-19T23:59:59.000Z

187

Early detection of deteriorations affecting neutrons boron detectors  

SciTech Connect

The objective of these studies is to design and to industrialize a new device taking back the features of the actual system of control of boron detectors and updating them by adding some analysis of the pulses shapes for predictive maintenance. (authors)

Domenech, T.; Hamrita, H.; Normand, S. [CEA, LIST, Laboratoire Capteur et Architectures Electroniques, F-91191 Gif/Yvette (France); Daviaud, J. P. [EDF, DPN, 1 place Pleyel, 93 282 Saint Denis Cedex (France); Laroche, M. [EDF, SEPTEN, 12-14 rue Dutrievoz, 69628 Villeurbanne Cedex (France)

2011-07-01T23:59:59.000Z

188

The use of isotopically tailored boron for advanced neutron shielding and moderating applications  

E-Print Network (OSTI)

cm. The incident neutron flux was measured first without any shielding slab between the source and the detector. The first slab of shielding material was then placed nearest to the source and the transmitted intensity was measured by the detector... effects of nuclear radiation. This analysis examined the use of isotopically tailored boron for the purpose of moderating, reflecting and shielding neutrons. The source of neutrons in this study varied in energy from 0. 2 keV to 14 MeV. The material...

Deere, Laura Marie

2012-06-07T23:59:59.000Z

189

Phenomenological description of neutron capture cross sections at 30 keV  

E-Print Network (OSTI)

Studying published data of Maxwellian averaged neutron capture cross sections, we found simple phenomenological rules obeyed by the cross sections as a function of proton and neutron number. We use these rules to make predictions for cross sections of neutron capture on nuclei with proton number above 83, where very few data are available.

Miklos Kiss; Zoltan Trocsanyi

2011-04-01T23:59:59.000Z

190

Neutron Capture Measurements and Resonance Analysis of Dysprosium Y.R. Kang,1  

E-Print Network (OSTI)

Neutron Capture Measurements and Resonance Analysis of Dysprosium Y.R. Kang,1 M.W. Lee,1 T.I. Ro,2 The electron linear accelerator facility at the Rensselaer Polytechnic Institute was used to measure neutron capture yields of dysprosium with the time-of-flight method in the neutron energy region from 10 eV to 1

Danon, Yaron

191

Measurements of gamma dose and thermal neutron fluence in phantoms exposed to a BNCT epithermal beam with TLD-700  

Science Journals Connector (OSTI)

......epithermal neutron beam for boron neutron capture therapy...separation. INTRODUCTION Boron neutron capture therapy...accumulation of the isotope 10B in tumour tissue...necessary and that for the determination of the ratio R n, a...Carrara M., Borroni M. Determination of gamma dose and thermal......

G. Gambarini; D. Magni; V. Regazzoni; M. Borroni; M. Carrara; E. Pignoli; J. Burian; M. Marek; V. Klupak; L. Viererbl

2014-10-01T23:59:59.000Z

192

Transplantable Mouse Neoplasm Control by Neutron Capture Therapy  

Science Journals Connector (OSTI)

... Elemental boron enriched to 96 per cent of boron-10 was converted to borax, and then to the more soluble sodium pentaborate. For injections ... intravenous injection in the mouse. Drug, sodium pentaborate decahydrate; dose, 35 mg as boron-10/g body weight. Each point represents an average obtained from ten animals. The analyses ...

LEE E. FARR; T. KONIKOWSKI

1967-07-29T23:59:59.000Z

193

Neutron scattering length of lithium and boron and their isotopes  

Science Journals Connector (OSTI)

Coherent neutron scattering lengths and free cross sections were measured in order to determine the spin dependent scattering lengths of the isotopes of Li and B.

L. Koester; K. Knopf; W. Waschkowski

1983-01-01T23:59:59.000Z

194

Measurement of neutron capture on 50Ti at thermonuclear energies  

E-Print Network (OSTI)

At the Karlsruhe and Tuebingen 3.75 MV Van de Graaff accelerators the thermonuclear 50Ti(n,gamma)51Ti(5.8 min) cross section was measured by the fast cyclic activation technique via the 320.852 and 928.65 keV gamma-ray lines of the 51Ti-decay. Metallic Ti samples of natural isotopic composition and samples of TiO2 enriched in 50Ti by 67.53 % were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 30, 52, and 145 keV, respectively. The direct capture cross section was determined to be 0.387 +/- 0.011 mbarn at 30 keV. We found evidence for a bound state s-wave resonance with an estimated radiative width of 0.34 eV which destructively interfers with direct capture. The strength of a suggested s-wave resonance at 146.8 keV was determined. The present data served to calculate, in addition to the directly measured Maxwellian averaged capture cross sections at 25 and 52 keV, an improved stellar 50Ti(n,gamma)51Ti rate in the thermonuclear energy region from 1 to 250 keV. The new stellar rate leads at low temperatures to much higher values than the previously recommended rate, e.g., at kT=8 keV the increase amounts to about 50 %. The new reaction rate therefore reduces the abundance of 50Ti due to s-processing in AGB stars.

P. V. Sedyshev; P. Mohr; H. Beer; H. Oberhummer; Yu. P. Popov; W. Rochow

1999-07-28T23:59:59.000Z

195

A Neutron Resonance Capture Analysis Experimental Station at the ISIS Spallation Source  

Science Journals Connector (OSTI)

Neutron resonance capture analysis (NRCA) is a nuclear technique that is used to determine the elemental composition of materials and artifacts (e.g., bronze objects) of...

Pietropaolo, Antonino; Gorini, Giuseppe; Festa, Giulia; Reali, Enzo; Grazzi, Francesco; Schooneveld, Erik M

2010-01-01T23:59:59.000Z

196

Laser annealing of neutron irradiated boron-10 isotope doped diamond  

Science Journals Connector (OSTI)

10B isotope doped p-type diamond epilayer grown by chemical vapor deposition on (110) oriented type IIa diamond single crystal substrate was subjected to neutron transmutation at a fluence of 2.4...

K. Jagannadham; M. J. Lance; J. E. Butler

2011-04-01T23:59:59.000Z

197

Neutron-capture elements in the very metal-poor star HD88609: another st ar with excesses of light neutron-capture elements  

E-Print Network (OSTI)

We obtained a high resolution, high signal-to-noise UV-blue spectrum of the extremely metal-poor red giant HD88609 to determine the abundances of heavy elements. Nineteen neutron-capture elements are detected in the spectrum. Our analysis revealed that this object has large excesses of light neutron-capture elements while heavy neutron-capture elements are deficient. The abundance pattern shows a continuously decreasing trend, as a function of atomic number, from Sr to Yb, which is quite different from those in stars with excesses of r-process elements. Such an abundance pattern is very similar to that of HD122563 that was studied by our previous work. The results indicate that the abundance pattern found in the two stars could represent the pattern produced by the nucleosynthesis process that provided light neutron-capture elements in the very early Galaxy.

Satoshi Honda; Wako Aoki; Yuhri Ishimaru; Shinya Wanajo

2007-05-27T23:59:59.000Z

198

Glossary Term - Electron Capture  

NLE Websites -- All DOE Office Websites (Extended Search)

Electron Electron Previous Term (Electron) Glossary Main Index Next Term (Electron Volt (eV)) Electron Volt (eV) Electron Capture After electron capture, an atom contains one less proton and one more neutron. Electron capture is one process that unstable atoms can use to become more stable. During electron capture, an electron in an atom's inner shell is drawn into the nucleus where it combines with a proton, forming a neutron and a neutrino. The neutrino is ejected from the atom's nucleus. Since an atom loses a proton during electron capture, it changes from one element to another. For example, after undergoing electron capture, an atom of carbon (with 6 protons) becomes an atom of boron (with 5 protons). Although the numbers of protons and neutrons in an atom's nucleus change

199

The Thermal Neutron Capture Cross Sections of Pa231 and Pa232  

Science Journals Connector (OSTI)

The neutron capture cross section of Pa231 has been determined to be 293 barns, the largest uncertainty in this determination being due to the uncertainty in the half-life of U232 and being of the order of 15 percent.The neutron capture cross section of Pa232 was determined to be about 40{+40}{-20} barns.

R. Elson; P. A. Sellers; E. R. John

1953-04-01T23:59:59.000Z

200

Novel Boron-10-based detectors for Neutron Scattering Science  

E-Print Network (OSTI)

Nowadays neutron scattering science is increasing its instrumental power. Most of the neutron sources in the world are pushing the development of their technologies to be more performing. The neutron scattering development is also pushed by the European Spallation Source (ESS) in Sweden, a neutron facility which has just started construction. Concerning small area detectors (1m^2), the 3He technology, which is today cutting edge, is reaching fundamental limits in its development. Counting rate capability, spatial resolution and cost-e?ectiveness, are only a few examples of the features that must be improved to ful?fill the new requirements. On the other hand, 3He technology could still satisfy the detector requirements for large area applications (50m^2), however, because of the present 3He shortage that the world is experiencing, this is not practical anymore. The recent detector advances (the Multi-Grid and the Multi-Blade prototypes) developed in the framework of the collaboration between the Institut Laue...

Piscitelli, Francesco

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Neutron and gamma width correlations in neutron capture reactions: A comparative study  

Science Journals Connector (OSTI)

Three different procedures are generally adopted in the analysis of correlation observed between neutron and ? widths in neutron capture experiments. We present a quantitative comparison of the three methods, the valence model, optical model, and shell model with an "exact" calculation including core excitation effects. The Sn28(n, ?) reaction is taken as an example which demonstrates that the approximation used for the single particle amplitudes and the omission of core excitation effects are possible sources of error in conventional calculations. Among the conventional procedures we conclude that because of possible external region contributions and its lack of sensitivity to the potential used, the optical model formulation of Lane and Mughabgab represent the most useful alternative.NUCLEAR REACTIONS (?, ?) reaction, neutron and ? width correlation.

D. Halderson and B. Castel

1978-09-01T23:59:59.000Z

202

Muon capture on deuteron and the neutron-neutron scattering length  

E-Print Network (OSTI)

The muon capture reaction mu + 2H --> nu_mu + n + n is studied with nuclear potentials and charge-changing weak currents, derived within chiral effective field theory. The next-to-next-to-next-to leading order (N3LO) chiral potential with cutoff parameter Lambda=500 MeV is used, but the low-energy constant (LEC) determining the neutron-neutron S-wave scattering length (a_{nn}) is varied so as to obtain four different values, which are a_{nn}=-18.95 fm, -16.0 fm, -22.0 fm, and +18.22 fm. The first value is the present empirical one, while the last one is chosen such as to lead to a di-neutron bound system with a binding energy of 139 keV. The LEC's c_D and c_E, present in the three-nucleon potential and axial-vector current (c_D), are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The muon capture rate on the deuteron in the doublet hyperfine initial state is found to be 399(3) s^{-1} for a_{nn}=-18.95 and -16.0 fm; and 400(3) s^{-1} for a_{nn}=-22.0 fm. However, in the case of a_{nn}=+18.22 fm, the result of 275(3) s^{-1} (135(3) s^{-1}) is obtained, when the di-neutron system in the final state is unbound (bound). The muon capture mu + 3He --> nu_mu + 3H is also analyzed, and the total capture rate is found to be 1494(15) s^{-1}, 1491(16) s^{-1}, 1488(18) s^{-1}, and 1475(16) s^{-1} for a_{nn}=-18.95 fm, -16.0 fm, -22.0 fm, and +18.22 fm, respectively. All the theoretical uncertainties are due to the fitting procedure and radiative corrections. Our results seem to exclude the possibility of constraining a negative a_{nn} with an uncertainty of less than ~ +/-3 fm through an accurate determination of the muon capture rates. However, a comparison with the already available experimental data discourages the possibility of a bound di-neutron state (positive a_{nn}).

L. E. Marcucci; R. Machleidt

2014-09-15T23:59:59.000Z

203

Neutron-capture elements in the s- and r-process-rich stars: Constraints on neutron-capture nucleosynthesis processes  

E-Print Network (OSTI)

The chemical abundances of the very metal-poor double-enhanced stars are excellent information for setting new constraints on models of neutron-capture processes at low metallicity. These stars are known as s+r stars, since they show enhancements of both s-process and r-process elements. The observed abundance ratios for the double-enhanced stars can be explained by those of stars that were polluted by an AGB star and subsequently accreted very significant amounts of r-process material out of an AIC (accretion-induced collapse) or Type 1.5 supernova. In this paper we present for the first time an attempt to fit the elemental abundances observed in the s- and r-rich, very metal-poor stars using a parametric model and suggest a new concept of component coefficients to describe the contributions of the individual neutron-capture processes to double-enhanced stars. We find that the abundance ratios of these stars are best fitted by enrichments of s- and r-process material. The overlap factor in the AGB stars where the observed s-process elements were produced lies between 0.1 and 0.81. Taking into account the dependence of the initial-final mass relations on metallicity, this wide range of values could possibly be explained by a wide range of core-mass values of AGB stars at low metallicity. The component coefficient of the r-process is strongly correlated with the component coefficient of the s-process for the double-enhanced stars. This is significant evidence that the r-process material in double-enhanced stars comes from an AIC or Type 1.5 supernova.

Bo Zhang; Kun Ma; Guide Zhou

2006-05-14T23:59:59.000Z

204

Boron-10 Distribution of p-Boronophenylalanine in the Experimental Brain Tumor in the Rats  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) has been employed in the treatment of malignant brain tumor in human. In this type of radiation therapy, biodistribution of 10B in tumor and peritumoral tissue is highly impor...

Munekazu Nakaichi; Yuko Hori; Toshinari Hasegawa…

2001-01-01T23:59:59.000Z

205

Muon capture on deuteron and the neutron-neutron scattering length  

E-Print Network (OSTI)

The muon capture reaction mu + 2H --> nu_mu + n + n is studied with nuclear potentials and charge-changing weak currents, derived within chiral effective field theory. The next-to-next-to-next-to leading order (N3LO) chiral potential with cutoff parameter Lambda=500 MeV is used, but the low-energy constant (LEC) determining the neutron-neutron S-wave scattering length (a_{nn}) is varied so as to obtain four different values, which are a_{nn}=-18.95 fm, -16.0 fm, -22.0 fm, and +18.22 fm. The first value is the present empirical one, while the last one is chosen such as to lead to a di-neutron bound system with a binding energy of 139 keV. The LEC's c_D and c_E, present in the three-nucleon potential and axial-vector current (c_D), are constrained to reproduce the A=3 binding energies and the triton Gamow-Teller matrix element. The muon capture rate on the deuteron in the doublet hyperfine initial state is found to be 399(3) s^{-1} for a_{nn}=-18.95 and -16.0 fm; and 400(3) s^{-1} for a_{nn}=-22.0 fm. However, ...

Marcucci, L E

2014-01-01T23:59:59.000Z

206

Computational characterization and experimental validation of the thermal neutron source for neutron capture therapy research at the University of Missouri  

SciTech Connect

Parameter studies, design calculations and neutronic performance measurements have been completed for a new thermal neutron beamline constructed for neutron capture therapy cell and small-animal radiobiology studies at the University of Missouri Research Reactor. The beamline features the use of single-crystal silicon and bismuth sections for neutron filtering and for reduction of incident gamma radiation. The computational models used for the final beam design and performance evaluation are based on coupled discrete-ordinates and Monte Carlo techniques that permit detailed modeling of the neutron transmission properties of the filtering crystals with very few approximations. Validation protocols based on neutron activation spectrometry measurements and rigorous least-square adjustment techniques show that the beam produces a neutron spectrum that has the anticipated level of thermal neutron flux and a somewhat higher than expected, but radio-biologically insignificant, epithermal neutron flux component. (authors)

Broekman, J. D. [University of Missouri, Research Reactor Center, 1513 Research Park Drive, Columbia, MO 65211-3400 (United States); Nigg, D. W. [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415 (United States); Hawthorne, M. F. [University of Missouri, International Institute of Nano and Molecular Medicine, 1514 Research Park Dr., Columbia, MO 65211-3450 (United States)

2013-07-01T23:59:59.000Z

207

Neutron-Capture Nucleosynthesis in the First Stars  

E-Print Network (OSTI)

Recent studies suggest that metal-poor stars enhanced in carbon but containing low levels of neutron-capture elements may have been among the first to incorporate the nucleosynthesis products of the first generation of stars. We have observed 16 stars with enhanced carbon or nitrogen using the MIKE Spectrograph on the Magellan Telescopes at Las Campanas Observatory and the Tull Spectrograph on the Smith Telescope at McDonald Observatory. We present radial velocities, stellar parameters, and detailed abundance patterns for these stars. Strontium, yttrium, zirconium, barium, europium, ytterbium, and other heavy elements are detected. In four stars, these heavy elements appear to have originated in some form of r-process nucleosynthesis. In one star, a partial s-process origin is possible. The origin of the heavy elements in the rest of the sample cannot be determined unambiguously. The presence of elements heavier than the iron group offers further evidence that zero-metallicity rapidly-rotating massive stars a...

Roederer, Ian U; Thompson, Ian B; Shectman, Stephen A; Sneden, Chris

2014-01-01T23:59:59.000Z

208

Neutron Capture Cross Section Measurement on $^{238}$Pu at DANCE  

SciTech Connect

The proposed neutron capture measurement for {sup 238}Pu was carried out in Nov-Dec, 2010, using the DANCE array at LANSCE, LANL. The total beam-on-target time is about 14 days plus additional 5 days for the background measurement. The target was prepared at LLNL with the new electrplating cell capable of plating the {sup 238}Pu isotope simultaneously on both sides of the 3-{micro}m thick Ti backing foil. A total mass of 395 {micro}g with an activity of 6.8 mCi was deposited onto the area of 7 mm in diameter. The {sup 238}Pu sample was enriched to 99.35%. The target was covered by 1.4 {micro}m double-side aluminized mylar and then inserted into a specially designed vacuum-tight container, shown in Fig. 1, for the {sup 238}Pu containment. The container was tested for leaks in the vacuum chamber at LLNL. An identical container without {sup 238}Pu was made as well and used as a blank for the background measurement.

Chyzh, A; Wu, C Y

2011-02-14T23:59:59.000Z

209

Production of heavy and superheavy neutron-rich nuclei in neutron capture processes  

Science Journals Connector (OSTI)

The neutron capture process is considered as an alternative method for production of superheavy (SH) nuclei. Strong neutron fluxes might be provided by nuclear reactors and nuclear explosions in the laboratory frame and by supernova explosions in nature. All these cases are discussed in the paper. There are two gaps of short-lived nuclei (one is the well-known fermium gap and the other one is located in the region of Z=106–108 and N?170) which impede the formation of SH nuclei by rather weak neutron fluxes realized at available nuclear reactors. We find that in the course of multiple (rather “soft”) nuclear explosions these gaps may be easily bypassed, and thus, a measurable amount of the neutron-rich long-living SH nuclei located at the island of stability may be synthesized. Existing pulsed reactors do not allow one to bypass these gaps. We formulate requirements for the pulsed reactors of the next generation that could be used for production of long-living SH nuclei. Natural formation of SH nuclei (in supernova explosions) is also discussed. The yield of SH nuclei relative to lead is estimated to be about 10?12, which is not beyond the experimental sensitivity for a search of SH elements in cosmic rays.

V. I. Zagrebaev; A. V. Karpov; I. N. Mishustin; Walter Greiner

2011-10-24T23:59:59.000Z

210

Molecular Targeting and Treatment of an Epidermal Growth Factor Receptor–Positive Glioma Using Boronated Cetuximab  

Science Journals Connector (OSTI)

...neutron capture therapy (BNCT) is based on the nuclear capture and fission reactions that occur when nonradioactive boron-10 is irradiated with low energy (e 0.025 eV) thermal neutrons to produce 11B in an unstable form, which undergoes...

Gong Wu; Weilian Yang; Rolf F. Barth; Shinji Kawabata; Michele Swindall; Achintya K. Bandyopadhyaya; Werner Tjarks; Behrooz Khorsandi; Thomas E. Blue; Amy K. Ferketich; Ming Yang; Gregory A. Christoforidis; Thomas J. Sferra; Peter J. Binns; Kent J. Riley; Michael J. Ciesielski; Robert A. Fenstermaker

2007-02-15T23:59:59.000Z

211

Thermal-Neutron-Capture Gamma Rays in Yb170, Yb172, and Yb174  

Science Journals Connector (OSTI)

A Ge(Li) detector was used to investigate the ? spectra following thermal neutron capture in enriched isotope targets of Yb170, Yb172, and Yb174. In addition to capture in these isotopes, ? lines were identified as resulting from thermal capture in Yb171 and Yb173. The neutron separation energies of Yb171, Yb172, Yb173, Yb174, and Yb175 were found to be 6616, 8023, 6365, 7465, and 5819 keV, respectively. The experimental error is ±3 keV in all cases. For capture by the even-even isotopes, the energies and intensities of ? transitions originating from the capture state are presented together with the spins and Nilsson assignments of the low-lying rotational bands which they populate. Our measurements are compared with those in other experiments, and the results of our measurements are discussed. Regularities in the decay of the capture state to low-lying Nilsson levels have now been observed in comparing thermal neutron capture by different even-even nuclei in the region A=176. The regularities include relatively strong population of Nilsson bands with ? equal to zero or 1 as compared to population of bands with ? greater than 1. In addition, there seems to be a preference for the capture state decaying to particle rather than hole bands. A purely statistical version of thermal neutron capture would not seem to hold in this mass region.

A. I. Namenson and J. C. Ritter

1969-07-20T23:59:59.000Z

212

Investigation of elemental analysis using neutron-capture gamma ray spectra  

E-Print Network (OSTI)

This thesis evaluated the potential of neutron-capture gamma rays in elemental analysis. A large portion of the work was devoted to the development of a method for the analysis of weak peaks in gamma ray spectra. This was ...

Hamawi, John Nicholas

1969-01-01T23:59:59.000Z

213

Lambda-Neutron Scattering Lengths from Radiative K-minus Capture  

E-Print Network (OSTI)

Radiative capture of the K-minus by the deuteron as a reaction for measurement of the Lambda-neutron scattering lengths. The use of spin information to separate the singlet and triplet scattering lengths is treated.

W. R. Gibbs; S. A. Coon; H. K. Han; B. F. Gibson

2000-01-02T23:59:59.000Z

214

Neutron capture measurement on {sup 173}Lu at LANSCE with DANCE detector  

SciTech Connect

The (n,{gamma}) cross section on the unstable {sup 173}Lu(t{sub 1/2} = 1.37y) has been measured from thermal energy up to 200 eV at Los Alamos Neutron Science Center (LANSCE) with The Detector for Advanced Neutron Capture Experiements (DANCE). The main aim of this study is to validate and optimize reaction models for unstable nucleus. A preliminary capture yield will be presented in this paper.

Theroine, C.; Ebran, A.; Meot, V.; Roig, O. [CEA DAM DIF, F-91297 Arpajon (France); Bond, E. M.; Bredeweg, T. A.; Couture, A.; Haight, R. C.; Jandel, M.; Nortier, F. M.; O'Donnell, J. M.; Rundberg, R. S.; Taylor, W. A.; Ullmann, J. L.; Viera, D. J.; Wilhelmy, J. B.; Wouters, J. M. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2013-06-10T23:59:59.000Z

215

Convection-enhanced Delivery of Boronated Epidermal Growth Factor for Molecular Targeting of EGF Receptor-positive Gliomas  

Science Journals Connector (OSTI)

...Chandra S., Barth R. F., Yang W., Joel D. D., Coderre J. Quantitative imaging and microlocalizaton of boron-10 in brain tumors and infiltrating tumor cells by SIMS ion microscopy: Relevance to neutron capture therapy. Cancer Res...

Weilian Yang; Rolf F. Barth; Dianne M. Adams; Michael J. Ciesielski; Robert A. Fenstermaker; Supriya Shukla; Werner Tjarks; Michael A. Caligiuri

2002-11-15T23:59:59.000Z

216

Precision Measurement of PArity Violation in Polarized Cold Neutron Capture on the Proton: the NPDGamma Experiment  

E-Print Network (OSTI)

The NPDGamma experiment at the Los Alamos Neutron Science Center (LANSCE) is dedicated to measure with high precision the parity violating asymmetry in the $\\gamma$ emission after capture of spin polarized cold neutrons in para-hydrogen. The measurement will determine unambiguously the weak pion-nucleon-nucleon ($\\pi NN$) coupling constant {\\it f$^1_{\\pi}$}

Lauss Bernhard

2006-01-02T23:59:59.000Z

217

Design and optimization of 6li neutron-capture pulse mode ion chamber  

E-Print Network (OSTI)

The purpose of this research is to design and optimize the performance of a unique, inexpensive 6Li neutron-capture pulse-mode ion chamber (LiPMIC) for neutron detection that overcomes the fill-gas contamination stemming from outgas of detector...

Chung, Kiwhan

2009-05-15T23:59:59.000Z

218

Measurement of the keV-neutron capture cross section and capture gamma-ray spectrum of isotopes around N=82 region  

SciTech Connect

The keV-neutron capture cross section and capture {gamma}-ray spectra of nuclides with a neutron magic number N= 82, {sup 139}La and {sup 142}Nd, were newly measured by the time-of-flight method. Capture {gamma}-rays were detected with an anti-Compton NaI(T1) spectrometer, and the pulse-height weighting technique was applied to derive the neutron capture cross section. The results were provided with our previous measurements of other nuclides around N= 82, {sup 140}Ce, {sup 141}Pr, {sup 143}Nd and {sup 145}Nd.

Katabuchi, Tatsuya; Igashira, Masayuki [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

2012-11-12T23:59:59.000Z

219

Measurements of neutron capture cross section for {sup 207,208}Pb  

SciTech Connect

The neutron capture cross sections for {sup 207,208}Pb have been measured in the neutron energy region from 10 to 110 keV. The ?-rays cascaded from a capture state to the ground state or low-lying states of {sup 208,209}Pb were observed for the first time, using an anti-Compton Nal(Tl) spectrometer and a TOF method. The observed discrete ?-ray energy spectra enabled us to determine neutron capture cross sections for {sup 207,208}Pb with small systematic errors, since we could distinguish ?-ray of {sup 207,208}Pb(n,?) reactions from background ?-ray with use of the ?-ray spectra. The obtained cross sections include both contributions of resonance and direct capture components different from the previous TOF measurements.

Segawa, M.; Toh, Y.; Harada, H.; Kitatani, F.; Koizumi, M.; Fukahori, T.; Iwamoto, N.; Iwamoto, O. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Oshima, M. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan and Japan Chemical Analysis Center (Japan); Hatsukawa, Y. [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Nagai, Y. [Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Igashira, M. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550 (Japan); Kamada, S. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550, Japan and National Maritime Research Institute (Japan); Tajika, M. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550, Japan and Hitachi Solutions, Ltd. (Japan)

2014-05-02T23:59:59.000Z

220

Multi-Grid Boron-10 detector for large area applications in neutron scattering science  

E-Print Network (OSTI)

The present supply of 3He can no longer meet the detector demands of the upcoming ESS facility and continued detector upgrades at current neutron sources. Therefore viable alternative technologies are required to support the development of cutting-edge instrumentation for neutron scattering science. In this context, 10B-based detectors are being developed by collaboration between the ESS, ILL, and Link\\"{o}ping University. This paper reports on progress of this technology and the prospects applying it in modern neutron scattering experiments. The detector is made-up of multiple rectangular gas counter tubes coated with B4C, enriched in 10B. An anode wire reads out each tube, thereby giving position of conversion in one of the lateral co-ordinates as well as in depth of the detector. Position resolution in the remaining co-ordinate is obtained by segmenting the cathode tube itself. Boron carbide films have been produced at Link\\"{o}ping University and a detector built at ILL. The characterization study is pres...

Andersen, Ken; Birch, Jens; Buffet, Jean-Claude; Correa, Jonathan; van Esch, Patrick; Guerard, Bruno; Hall-Wilton, Richard; Hultman, Lars; Höglund, Carina; Jensen, Jens; Khaplanov, Anton; Kirstein, Oliver; Piscitelli, Francesco; Vettier, Christian

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Nuclear Instruments and Methods in Physics Research A 562 (2006) 380388 Modeling solid-state boron carbide low energy neutron detectors  

E-Print Network (OSTI)

carbide low energy neutron detectors C. Lundstedta,b , A. Harkena,c , E. Daya,c , B.W. Robertsona,c , S types of solid-state boron carbide detector. These results provide the basis for distinguishing between-section. At the University of Nebraska, Lincoln (UNL), a semiconducting form of boron carbide has been developed over

222

Neutron-capture elements in the metal-poor globular cluster M15  

E-Print Network (OSTI)

We report on observations of six giants in the globular cluster M15 (NGC 7078) using the Subaru Telescope to measure neutron-capture elemental abundances. Our abundance analyses based on high-quality blue spectra confirm the star-to-star scatter in the abundances of heavy neutron-capture elements (e.g., Eu), and no significant s-process contribution to them, as was found in previous studies. We have found, for the first time, that there are anti-correlations between the abundance ratios of light to heavy neutron-capture elements ([Y/Eu] and [Zr/Eu]) and heavy ones (e.g., Eu). This indicates that light neutron-capture elements in these stars cannot be explained by only a single r-process. Another process that has significantly contributed to the light neutron-capture elements is required to have occurred in M15. Our results suggest a complicated enrichment history for M15 and its progenitor.

Kaori Otsuki; Satoshi Honda; Wako Aoki; Toshitaka Kajino; Grant J. Mathews

2006-03-13T23:59:59.000Z

223

The Role of Dynamic Positron Emission Tomography for Quantifying Boron-10 in Vivo Using the Fructose Complex of Fluorine-18 Labeled Boronophenylalanine  

Science Journals Connector (OSTI)

One of the major difficulties facing successful boron neutron capture therapy (BNCT) is the paucity of in vivo pharmacokinetic data.1 Analytical techniques such as prompt gamma analysis, secondary ion mass spectr...

G. W. Kabalka; G. T. Smith; T. L. Nichols…

2001-01-01T23:59:59.000Z

224

Neutron Capture Reactions in a d(14)+Be Fast Neutron Beam  

Science Journals Connector (OSTI)

Since 1978 at the Essen University Hospital a compact cyclotron has been used for fast neutron therapy with neutrons produced by 14 MeV deuterons incident on ... seated tumors (Fig 1). During fast neutron therapy...

W. Sauerwein; I. Heselmann; F. Pöller…

1992-01-01T23:59:59.000Z

225

Measurement on the thermal neutron capture cross section of w-180  

E-Print Network (OSTI)

We have measured the thermal neutron capture cross section for w-180 nucleus. There is only one previous data on this cross section with a value of 30 $^{+300%}_{-100%}$ barn. To consider w-181 as a low energy neutrino source, the thermal neutron capture cross section should be measured more precisely to estimate the production rate of w-181 inside a nuclear reactor. We measured the cross section of w-180 with a natural tungsten foil and obtained a new value of 21.9 $\\pm$ 2.5 barn

W. G. Kang; Y. D. Kim; J. I. Lee; I. S. Hahn; A. R. Kim; H. J. Kim

2007-04-24T23:59:59.000Z

226

Neutron capture on 130Sn during r-process freeze-out  

E-Print Network (OSTI)

We examine the role of neutron capture on 130Sn during r-process freeze-out in the neutrino-driven wind environment of the core-collapse supernova. We find that the global r-process abundance pattern is sensitive to the magnitude of the neutron capture cross section of 130Sn. The changes to the abundance pattern include not only a relative decrease in the abundance of 130Sn and an increase in the abundance of 131Sn, but also a shift in the distribution of material in the rare earth and third peak regions.

J. Beun; J. C. Blackmon; W. R. Hix; G. C. McLaughlin; M. S. Smith; R. Surman

2008-06-24T23:59:59.000Z

227

Polarized-Neutron Capture in the Giant-Resonance Region of Ca41  

Science Journals Connector (OSTI)

The capture of fast polarized neutrons incident on Ca40 has been measured at an incident neutron energy of 10.0 MeV. The results indicate a significant non-E1 contribution in the giant-dipole-energy region of Ca41. When the data at En=10 MeV are analyzed with the use of a model, they are found to be consistent with an E2 strength which is (3.2±2.7)% of the total capture cross section. Some of the implications of this result are discussed.

M. Jensen; D. R. Tilley; H. R. Weller; N. R. Roberson; S. A. Wender; T. B. Clegg

1979-08-27T23:59:59.000Z

228

On the capture of dark matter by neutron stars  

E-Print Network (OSTI)

We calculate the number of dark matter particles that a neutron star accumulates over its lifetime as it rotates around the center of a galaxy, when the dark matter particle is a self-interacting boson but does not self-annihilate. We take into account dark matter interactions with baryonic matter and the time evolution of the dark matter sphere as it collapses within the neutron star. We show that dark matter self-interactions play an important role in the rapid accumulation of dark matter in the core of the neutron star. We consider the possibility of determining an exclusion region of the parameter space for dark matter mass and dark matter interaction cross sections based on the observation of old neutron stars with strong dark matter self-interactions. We show that for a dark matter density of $~10^3$ GeV/cm$^3$ and dark matter mass $m_\\chi$ less than approximately 10 GeV, there is a potential exclusion region for dark matter interactions with nucleons that is three orders of magnitude more stringent than without self-interactions. The potential exclusion region for dark matter self-interaction cross sections is many orders of magnitude stronger than the current Bullet Cluster limit. For example, for high dark matter density regions, we find that for $m_\\chi\\sim 10$ GeV when the dark matter interaction cross section with the nucleons ranges from $\\sigma_{\\chi n}\\sim 10^{-52}$ cm$^2$ to $10^{-57}$ cm$^2$, the dark matter self-interaction cross section limit is $\\sigma_{\\chi\\chi}ten orders of magnitude stronger than the Bullet Cluster limit.

Tolga Guver; Arif Emre Erkoca; Mary Hall Reno; Ina Sarcevic

2014-04-09T23:59:59.000Z

229

Subcellular boron and fluorine distributions with SIMS ion microscopy in BNCT and cancer research  

SciTech Connect

The development of a secondary ion mass spectrometry (SIMS) based technique of Ion Microscopy in boron neutron capture therapy (BNCT) was the main goal of this project, so that one can study the subcellular location of boron-10 atoms and their partitioning between the normal and cancerous tissue. This information is fundamental for the screening of boronated drugs appropriate for neutron capture therapy of cancer. Our studies at Cornell concentrated mainly on studies of glioblastoma multiforme (GBM). The early years of the grant were dedicated to the development of cryogenic methods and correlative microscopic approaches so that a reliable subcellular analysis of boron-10 atoms can be made with SIMS. In later years SIMS was applied to animal models and human tissues of GBM for studying the efficacy of potential boronated agents in BNCT. Under this grant the SIMS program at Cornell attained a new level of excellence and collaborative SIMS studies were published with leading BNCT researchers in the U.S.

Subhash Chandra

2008-05-30T23:59:59.000Z

230

Quantitative interpretation of pulsed neutron capture logs: Part 1 --Fast numerical simulation  

E-Print Network (OSTI)

Jordan G. Mimoun1 , Carlos Torres-Verdi´n2 , and William E. Preeg3 ABSTRACT Pulsed neutron capture (PNC for shoulder-bed effects on R logs acquired in sand- shale laminated reservoirs. Because of diffusion effects responses of pure-sand and pure- shale end members of the sedimentary sequence. We have developed a new

Torres-Verdín, Carlos

231

Neutron-capture elements in the very metal-poor star HD122563  

E-Print Network (OSTI)

We obtained high resolution, high S/N spectroscopy for the very metal-poor star HD122563 with the Subaru Telescope High Dispersion Spectrograph. Previous studies have shown that this object has excesses of light neutron-capture elements, while its abundances of heavy ones are very low. In our spectrum covering 3070 - 4780 A of this object, 19 neutron-capture elements have been detected, including seven for the first time in this star (Nb, Mo, Ru, Pd, Ag, Pr, and Sm). Upper limits are given for five other elements including Th. The abundance pattern shows a gradually decreasing trend, as a function of atomic number, from Sr to Yb, which is quite different from those in stars with excesses of r-process elements. This abundance pattern of neutron-capture elements provides new strong constraints on the models of nucleosynthesis responsible for the very metal-poor stars with excesses of light neutron-capture elements but without enhancement of heavy ones.

S. Honda; W. Aoki; Y. Ishimaru; S. Wanajo; S. G. Ryan

2006-02-06T23:59:59.000Z

232

Accelerator based neutron source for neutron capture therapy B. Bayanov, Yu. Belchenko, V. Belov, V. Davydenko, A. Donin, A. Dranichnikov, A. Ivanov,  

E-Print Network (OSTI)

approach is based upon vacuum insulation tandem accelerator (VITA) and near threshold 7 Li(p,n)7 Be neutron Fig. 1. Negative hydrogen ion beam is injected into electrostatic vacuum insulation tandem acceleratorAccelerator based neutron source for neutron capture therapy B. Bayanov, Yu. Belchenko, V. Belov, V

Taskaev, Sergey Yur'evich

233

A microdosimetric approach to the thermal neutron fluence prescription for clinical BNCT  

Science Journals Connector (OSTI)

......Comput. Assist. Tomogr. 4 , 489-491 (1980). 15. Kobayashi, T. and Kanda, K. Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radiat. Res. 91 , 77-94 (1982). 16. Coderre, J. A......

E. H. Kim; C. H. Rhee

2004-12-01T23:59:59.000Z

234

Diversity of abundance patterns of neutron-capture elements in very metal-poor stars  

SciTech Connect

Observations of Very Metal-Poor stars indicate that there are at least two sites to r-process; “weak r-process” and “main r-process”. A question is whether these two are well separated or there exists a variation in the r-process. We present the results of abundance analysis of neutron-capture elements in the two Very Metal-Poor stars HD107752 and HD110184 in the Milky Way halo observed with the Subaru Telescope HDS. The abundance patterns show overabundace at light n-capture elements (e.g. Sr, Y), inferring the element yielding of weak r-process, while heavy neutron-capture elements (e.g. Ba, Eu) are deficient; however, the overabundance of light ones is not as significant as that previously found in stars representing the weak r-process (e.g. HD122563; Honda et al. 2006). Our study show diversity in the abundance patterns from light to heavy neutron-capture elements in VMP stars, suggesting a variation in r-process, which may depend on electron fraction of environment.

Aoki, Misa; Ishimaru, Yuhri [International Christian University 10-2, Osawa, Mitaka, Tokyo 181-0015 (Japan); Aoki, Wako; Wanajo, Shinya [National Astronomical Observatory of Japan (NAOJ) 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

2014-05-02T23:59:59.000Z

235

Non-standard Fickian self-diffusion of isotopically pure boron observed by neutron reflectometry and depth profiling  

SciTech Connect

Neutron reflectometry (NR) studies of thin films of amorphous {sup 11}B/{sup 10}B on silicon indicate that a non-standard form of Fickian diffusion occurs across the boron interface upon annealing. In order to verify this observation, the samples were examined by neutron depth profiling (NDP). Comparison of the results from models of a step function, standard Fickian diffusion and Fickian diffusion with a fixed composition at the interface were made and compared to the previous NR results. The diffusion constant resulting from the non-standard Fickian model for the NDP data differs slightly from that obtained from the commonly used Fickian diffusion model and is not inconsistent with the NR results. This finding suggests that more information regarding diffusion at interfaces can be gained from these higher resolution neutron scattering techniques.

Baker, S.M.; Wu, K. [Harvey Mudd Coll., Claremont, CA (United States). Dept. of Chemistry; Smith, G.S.; Hubbard, K.M.; Nastasi, M. [Los Alamos National Lab., NM (United States); Downing, R.G.; Lamaze, G.P. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1995-12-31T23:59:59.000Z

236

Parity violation in neutron capture on the proton: determining the weak pion-nucleon coupling  

E-Print Network (OSTI)

We investigate the parity-violating analyzing power in neutron capture on the proton at thermal energies in the framework of chiral effective field theory. By combining this analysis with a previous analysis of parity violation in proton-proton scattering, we are able to extract the size of the weak pion-nucleon coupling constant. The uncertainty is significant and dominated by the experimental error which is expected to be reduced soon.

de Vries, J; Meißner, Ulf-G; Nogga, A; Epelbaum, E; Kaiser, N

2015-01-01T23:59:59.000Z

237

Gamma-ray cascade transitions from resonant neutron capture in Cd-111 and Cd-113  

SciTech Connect

A neutron-capture experiment on {sup nat}Cd has been carried out at DANCE. Multiple-fold coincidence {gamma}-ray spectra have been collected from J=0, 1 resonances in {sup 111}Cd and {sup 113}Cd. The cascades ending at the ground state can be described by the SLO model while the cascades ending at the 2+ states are better reproduced by the mixed SLO+KMF model.

Rusev, Gencho Y. [Los Alamos National Laboratory

2012-08-27T23:59:59.000Z

238

Molecular Targeting of the Epidermal Growth Factor Receptor for Neutron Capture Therapy of Gliomas  

Science Journals Connector (OSTI)

...targeting of sufficient amounts of boron-10 to sustain a lethal 10B (n, a...selective uptake of sufficient amounts of boron-10 (109 atoms/cell) by tumor cells...starburst pattern, was boronated with a boron-10 enriched (98% 10B) methylisocyanato...

Rolf. F. Barth; Weilian Yang; Dianne M. Adams; Joan H. Rotaru; Supriya Shukla; Masaru Sekido; Werner Tjarks; Robert A. Fenstermaker; Michael Ciesielski; Marta M. Nawrocky; Jeffrey A. Coderre

2002-06-01T23:59:59.000Z

239

Measurement of neutron capture on $^{48}$Ca at thermal and thermonuclear energies  

E-Print Network (OSTI)

At the Karlsruhe pulsed 3.75\\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$\\gamma$)$^{49}$Ca(8.72\\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\\,keV $\\gamma$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\\,\\% were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 151, 176, and 218\\,keV, respectively. Additionally, the thermal capture cross-section was measured at the reactor BR1 in Mol, Belgium, via the prompt and decay $\\gamma$-ray lines using the same target material. The $^{48}$Ca(n,$\\gamma$)$^{49}$Ca cross-section in the thermonuclear and thermal energy range has been calculated using the direct-capture model combined with folding potentials. The potential strengths are adjusted to the scattering length and the binding energies of the final states in $^{49}$Ca. The small coherent elastic cross section of $^{48}$Ca+n is explained through the nuclear Ramsauer effect. Spectroscopic factors of $^{49}$Ca have been extracted from the thermal capture cross-section with better accuracy than from a recent (d,p) experiment. Within the uncertainties both results are in agreement. The non-resonant thermal and thermonuclear experimental data for this reaction can be reproduced using the direct-capture model. A possible interference with a resonant contribution is discussed. The neutron spectroscopic factors of $^{49}$Ca determined from shell-model calculations are compared with the values extracted from the experimental cross sections for $^{48}$Ca(d,p)$^{49}$Ca and $^{48}$Ca(n,$\\gamma$)$^{49}$Ca.

H. Beer; C. Coceva; P. V. Sedyshev; Yu. P. Popov; H. Herndl; R. Hofinger; P. Mohr; H. Oberhummer

1996-08-07T23:59:59.000Z

240

Determination of wax deposition and corrosion in pipelines by neutron back diffusion collimation and neutron capture gamma rays  

Science Journals Connector (OSTI)

Wax deposition in pipelines can be very costly for plant operation in oil industry. New techniques are needed for allocation and thickness determination of wax deposits. The timely removal of wax can make large saving in operational cost. Neutron back diffusion and neutron capture gamma rays were used in this study to measure paraffin, asphalt and polyethylene deposition thicknesses inside pipes and to enable simultaneous determination of scale and pipe corrosion. It was possible to determine a thickness change of less than one mm in 2 min. It was also possible to detect localized scale from a small region of the pipe of approximately 2 cm in diameter. Although experiments were performed in lab, the system can be made portable for field applications.

Samir Abdul-Majid

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Ionisation chamber containing boron as a neutron detector in medical accelerator fields  

Science Journals Connector (OSTI)

......oxfordjournals.org August 2007 research-article POSTER Presentations Ionisation chamber containing boron...was partially supported by the Polish Ministry of Science and Higher Education under the grant No. 2P05D06530. The authors would......

M. Zielczynski; M. A. Gryzinski; N. Golnik; P. Tulik

2007-08-01T23:59:59.000Z

242

Boron Neutron Capture Therapy (BNCT) of F98 Glioma Bearing Rats Using Boronophenylalanine (BPA) as a Capture Agent  

Science Journals Connector (OSTI)

Fifty percent of primary malignancies of the central nervous system are anaplastic astrocytomas and glioblastoma multiforme1. The prognosis of patients with these tumors is dismal despite aggressive surgery follo...

Khalid Z. Matalka; Rolf F. Barth; Alfred E. Staubus…

1993-01-01T23:59:59.000Z

243

Boron Neutron Capture Therapy of Cancer: Current Status and Future Prospects  

Science Journals Connector (OSTI)

...yield high linear energy transfer alpha particles...countries, and Argentina. Accelerators also...the Japan Atomic Energy Research Institute...reactor in Bariloche, Argentina (136). Other...yield high linear energy transfer alpha particles...countries, and Argentina. Accelerators also...

Rolf F. Barth; Jeffrey A. Coderre; M. Graça H. Vicente; and Thomas E. Blue

2005-06-01T23:59:59.000Z

244

Boron Neutron Capture Therapy for the Treatment of Oral Cancer in the Hamster Cheek Pouch Model  

Science Journals Connector (OSTI)

...National Atomic Energy Commission, 1429 Buenos Aires, Argentina, and Oral Pathology...National Atomic Energy Commission...Buenos Aires, Argentina. Phone: 54-11-6772-7149...National Atomic Energy Commission, 1429 Buenos Aires, Argentina. | Journal...

Erica L. Kreimann; Maria E. Itoiz; Juan Longhino; Herman Blaumann; Osvaldo Calzetta; and Amanda E. Schwint

2001-12-15T23:59:59.000Z

245

Boron Neutron Capture Therapy of Cancer: Current Status and Future Prospects  

Science Journals Connector (OSTI)

...reactor at the Nuclear Research Institute...in Kumatori, Japan (134); (g...will be a low-power fast-flux reactor...proportional to the power, measured in...reactors with high power, because a larger...by Hatanaka in Japan in 1967 following...several different nuclear reactors. Because...

Rolf F. Barth; Jeffrey A. Coderre; M. Graça H. Vicente; and Thomas E. Blue

2005-06-01T23:59:59.000Z

246

WHOLE-BODY DOSE EVALUATION WITH AN ADAPTIVE TREATMENT PLANNING SYSTEM FOR BORON NEUTRON CAPTURE THERAPY  

Science Journals Connector (OSTI)

......thoracoabdominal organ dose during BNCT for a brain tumour and maxillary sinus tumour was 50-360...for various organs during BNCT BNCT for a brain tumour The authors evaluated the undesirable...various organs during BNCT irradiation of a brain tumour, using a whole-body phantom......

Kenta Takada; Hiroaki Kumada; Tomonori Isobe; Toshiyuki Terunuma; Satoshi Kamizawa; Hideyuki Sakurai; Takeji Sakae; Akira Matsumura

2014-12-01T23:59:59.000Z

247

Delivery of Boron-10 for Neutron Capture Therapy by Means of Monoclonal Antibody - Starburst Dendrimer Immunoconjugates  

Science Journals Connector (OSTI)

The use of monoclonal antibodies (MoAbs) for the delivery of radionuclides, drugs and toxins for therapeutic purposes has been the subject of intensive investigation over the past decade. A few investigators, inc...

Rolf F. Barth; Albert H. Soloway…

1992-01-01T23:59:59.000Z

248

Strong neutrino cooling by cycles of electron capture and decay in neutron star crusts  

SciTech Connect

The temperature in the crust of an accreting neutron star, which comprises its outermost kilometre, is set by heating from nuclear reactions at large densities, neutrino cooling and heat transport from the interior. The heated crust has been thought to affect observable phenomena at shallower depths, such as thermonuclear bursts in the accreted envelope. Here we report that cycles of electron capture and its inverse, decay, involving neutron-rich nuclei at a typical depth of about 150 metres, cool the outer neutron star crust by emitting neutrinos while also thermally decoupling the surface layers from the deeper crust. This Urca mechanism has been studied in the context of white dwarfs13 and type Ia supernovae, but hitherto was not considered in neutron stars, because previous models1, 2 computed the crust reactions using a zero-temperature approximation and assumed that only a single nuclear species was present at any given depth. The thermal decoupling means that X-ray bursts and other surface phenomena are largely independent of the strength of deep crustal heating. The unexpectedly short recurrence times, of the order of years, observed for very energetic thermonuclear superbursts are therefore not an indicator of a hot crust, but may point instead to an unknown local heating mechanism near the neutron star surface.

Schatz, Hendrik [Michigan State University, East Lansing] [Michigan State University, East Lansing; Gupta, Sanjib [Indian Institute of Technology, Kanpur] [Indian Institute of Technology, Kanpur; Moeller, Peter [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Beard, Mary [University of Notre Dame, IN] [University of Notre Dame, IN; Brown, Edward [Michigan State University, East Lansing] [Michigan State University, East Lansing; Deibel, A. T. [Michigan State University, East Lansing] [Michigan State University, East Lansing; Gasques, Leandro [University of Sao Paulo, BRAZIL] [University of Sao Paulo, BRAZIL; Hix, William Raphael [ORNL] [ORNL; Keek, Laurens [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta; Lau, Rita [National Superconducting Cyclotron Laboratory (NSCL)] [National Superconducting Cyclotron Laboratory (NSCL); Steiner, Andrew M [University of Washington, Seattle] [University of Washington, Seattle; Wiescher, Michael [University of Notre Dame, IN] [University of Notre Dame, IN

2013-01-01T23:59:59.000Z

249

Alanine and TLD coupled detectors for fast neutron dose measurements in neutron capture therapy (NCT)  

Science Journals Connector (OSTI)

......the gamma rays in the reactor is different from that...Sesonske, A. Nuclear Reactor Engineering (Van Nostrand...column of the Tapiro reactor (ENEA-Casaccia RC...hence the precision and reliability of the fast neutron...Design Equipment Failure Analysis Gamma Rays therapeutic......

A. Cecilia; S. Baccaro; A. Cemmi; V. Colli; G. Gambarini; G. Rosi; L. Scolari

2004-08-01T23:59:59.000Z

250

Thermoluminescence dosimetry of a thermal neutron field and comparison with Monte Carlo calculations  

Science Journals Connector (OSTI)

......dosemeters (TLDs) regarding the determination of photon and neutron absorbed...disks, 8 1 mm2; Institute of Isotope and Surface Chemistry, IKI...thermoluminescence dosemeters for Boron Neutron Capture Therapy...dosemeters (TLDs) regarding the determination of photon and neutron absorbed......

A. C. Fernandes; J. P. Santos; A. Kling; J. G. Marques; I. C. Gonçalves; A. Ferro Carvalho; L. Santos; J. Cardoso; M. Osvay

2004-08-01T23:59:59.000Z

251

Calculations of the cross sections for the neutron acceleration, slowing down, and capture by the isomer "OmHf  

E-Print Network (OSTI)

Calculations of the cross sections for the neutron acceleration, slowing down, and capture for the isomer lsomHf in the energy range of the incoming neutron from 1keV to 5 MeV. Below 0.7 MeV the energy transferred to the neutron in the collision is positive on the average, i.e., the isomer is acting

Shlyakhter, Ilya

252

Neutron Capture in the r-Process -- Do We Know Them And Does It Make Any Difference?  

E-Print Network (OSTI)

The r-process involves neutron-rich nuclei far off stability for which no experimental cross sections are known. Therefore, one has to rely on theory which might be prone to considerable uncertainties far off stability. To investigate the impact of such uncertainties, nucleosynthesis in hot bubble models followed completely from high-temperature NSE to low-temperature neutron capture freeze-out were calculated with largely varied rates. Due to the (n,gamma)-(gamma,n) equilibrium established at the onset of the r-process, only late-time neutron captures are important which mainly modify the abundances around the third r-process peak.

T. Rauscher

2004-07-16T23:59:59.000Z

253

Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis  

E-Print Network (OSTI)

The $^{63}$Ni($n, \\gamma$) cross section has been measured for the first time at the neutron time-of-flight facility n\\_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian Averaged Cross Sections were calculated for thermal energies from kT = 5 keV to 100 keV with uncertainties around 20%. Stellar model calculations for a 25 M$_\\odot$ star show that the new data have a significant effect on the $s$-process production of $^{63}$Cu, $^{64}$Ni, and $^{64}$Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

C. Lederer; C. Massimi; S. Altstadt; J. Andrzejewski; L. Audouin; M. Barbagallo; V. Bécares; F. Bevá; F. Belloni; E. Berthoumieux; J. Billowes; V. Boccone; D. Bosnar; M. Brugger; M. Calviani; F. Calviño; D. Cano-Ott; C. Carrapiço; F. Cerutti; E. Chiaveri; M. Chin; N. Colonna; G. Cortés; M. A. Cortés-Giraldo; M. Diakaki; C. Domingo-Pardo; I. Duran; R. Dressler; N. Dzysiuk; C. Eleftheriadis; A. Ferrari; K. Fraval; S. Ganesan; A. R. García; G. Giubrone; M. B. Gómez-Hornillos; I. F. Gonçalves; E. González-Romero; E. Griesmayer; C. Guerrero; F. Gunsing; P. Gurusamy; D. G. Jenkins; E. Jericha; Y. Kadi; F. Käppeler; D. Karadimos; N. Kivel; P. Koehler; M. Kokkoris; G. Korschinek; M. Krtika; J. Kroll; C. Langer; H. Leeb; L. S. Leong; R. Losito; A. Manousos; J. Marganiec; T. Martínez; P. F. Mastinu; M. Mastromarco; M. Meaze; E. Mendoza; A. Mengoni; P. M. Milazzo; F. Mingrone; M. Mirea; W. Mondelaers; C. Paradela; A. Pavlik; J. Perkowski; M. Pignatari; A. Plompen; J. Praena; J. M. Quesada; T. Rauscher; R. Reifarth; A. Riego; F. Roman; C. Rubbia; R. Sarmento; P. Schillebeeckx; S. Schmidt; D. Schumann; G. Tagliente; J. L. Tain; D. Tarrío; L. Tassan-Got; A. Tsinganis; S. Valenta; G. Vannini; V. Variale; P. Vaz; A. Ventura; R. Versaci; M. J. Vermeulen; V. Vlachoudis; R. Vlastou; A. Wallner; T. Ware; M. Weigand; C. Weiß; T. J. Wright; P. Zugec

2013-04-11T23:59:59.000Z

254

Upper bounds on parity-violating ?-ray asymmetries in compound nuclei from polarized cold neutron capture  

Science Journals Connector (OSTI)

Parity-odd asymmetries in the electromagnetic decays of compound nuclei can sometimes be amplified above values expected from simple dimensional estimates by the complexity of compound nuclear states. Using a statistical approach, we estimate the root-mean-square of the distribution of expected parity-odd correlations s?n·k??, where s?n is the neutron spin and k?? is the momentum of the ?, in the integrated ? spectrum from the capture of cold polarized neutrons on Al, Cu, and In. We present measurements of the asymmetries in these and other nuclei. Based on our calculations, large enhancements of asymmetries were not predicted for the studied nuclei and the statistical estimates are consistent with our measured upper bounds on the asymmetries.

M. T. Gericke et al. (NPDGamma Collaboration)

2006-12-19T23:59:59.000Z

255

BINP accelerator based epithermal neutron source V. Aleynik a  

E-Print Network (OSTI)

: Boron neutron capture therapy Epithermal neutron source Accelerator a b s t r a c t Innovative facility in order to prevent the propagation of 7 Be radioactive isotope, (ii) the controlled eva- poration, which is the most power- ful and determines the further beam transport. To exclude the effect of non

Taskaev, Sergey Yur'evich

256

System and method for delivery of neutron beams for medical therapy  

DOE Patents (OSTI)

A neutron delivery system that provides improved capability for tumor control during medical therapy is disclosed. The system creates a unique neutron beam that has a bimodal or multi-modal energy spectrum. This unique neutron beam can be used for fast-neutron therapy, boron neutron capture therapy (BNCT), or both. The invention includes both an apparatus and a method for accomplishing the purposes of the invention. 5 figs.

Nigg, D.W.; Wemple, C.A.

1999-07-06T23:59:59.000Z

257

System and method for delivery of neutron beams for medical therapy  

DOE Patents (OSTI)

A neutron delivery system that provides improved capability for tumor control during medical therapy. The system creates a unique neutron beam that has a bimodal or multi-modal energy spectrum. This unique neutron beam can be used for fast-neutron therapy, boron neutron capture therapy (BNCT), or both. The invention includes both an apparatus and a method for accomplishing the purposes of the invention.

Nigg, David W. (Idaho Falls, ID); Wemple, Charles A. (Idaho Falls, ID)

1999-01-01T23:59:59.000Z

258

Neutron Transmission, Capture, and Scattering Measurements at the Gaerttner LINAC Center Y. Danon, L. Liu, E.J. Blain, A.M. Daskalakis, B.J. McDermott, K. Ramic, C.R. Wendorff  

E-Print Network (OSTI)

Neutron Transmission, Capture, and Scattering Measurements at the Gaerttner LINAC Center Y. Danon . As the energy of the neutrons increases to the keV region neutron resonance scattering becomes dominant compared to capture, and scattered neutrons can penetrate the 10 B4C liner of the NaI capture detector and get

Danon, Yaron

259

Are There Any Stars Lacking Neutron-Capture Elements? Evidence from Strontium and Barium  

E-Print Network (OSTI)

The cosmic dispersion in the abundances of the heavy elements strontium and barium in halo stars is well known. Strontium and barium are detected in most cool, metal-poor giants, but are these elements always detectable? To identify stars that could be considered probable candidates for lacking these elements, I examine the stellar abundance data available in the literature for 1148 field stars and 226 stars in dwarf galaxies, 776 of which have metallicities lower than [Fe/H]Strontium or barium have been detected in all field, globular cluster, and dwarf galaxy environments studied. All upper limits are consistent with the lowest detected ratios of [Sr/H] and [Ba/H]. The frequent appearance of these elements raises the intriguing prospect that at least one kind of neutron-capture reaction operates as often as the nucleosynthesis mechanisms that produce lighter elements, like magnesium, calcium, or iron, although the yields of heavy elements may be more variable.

Roederer, Ian U

2012-01-01T23:59:59.000Z

260

Gamma-gamma directional correlation measurements in 84Kr following thermal neutron capture by natural krypton  

Science Journals Connector (OSTI)

Directional correlations of gamma-ray cascades in 84Kr have been measured following thermal neutron capture by a pressurised natural krypton gas target. Gamma-ray singles spectra were measured up to 5.5 MeV and the correlation data were obtained for the energy range 0.2-2.5 MeV. A decay scheme was developed on the basis of coincidence measurements. The data allow spin-parity assignments to be made to most levels lying below 3.5 MeV and multipole mixing ratios to be evaluated for the more intense transitions. The results are fitted to the SU(5) limit of the IBM-1 and to the IBM-2 and are also compared with the predictions of the dynamic deformation model which indicates that 84Kr is the only krypton isotope with a prolate equilibrium shape. A possible mixed symmetry 2+ state at 2.623 MeV is identified.

S A Hamada; W D Hamilton; F Hoyler

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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261

Near-UV Observations of CS29497-030: New Constraints on Neutron-Capture Nucleosynthesis Processes  

E-Print Network (OSTI)

Employing spectra obtained with the new Keck I HIRES near-UV sensitive detector, we have performed a comprehensive chemical composition analysis of the binary blue metal-poor star CS29497-030. Abundances for 29 elements and upper limits for an additional seven have been derived, concentrating on elements largely produced via neutron-capture nucleosynthesis. Included in our analysis are the two elements that define the termination point of the slow neutron-capture process, lead and bismuth. We determine an extremely high value of [Pb/Fe] = +3.65 +/- 0.07 (sigma = 0.13) from three features, supporting the single-feature result obtained in previous studies. We also detect Bi for the first time in a metal-poor star. Our derived Bi/Pb ratio is in accord with those predicted from the most recent FRANEC calculations of the slow neutron-capture process in low-mass AGB stars. We find that the neutron-capture elemental abundances of CS29497-030 are best explained by an AGB model that also includes very significant amounts of pre-enrichment of rapid neutron-capture process material in the protostellar cloud out of which the CS29497-030 binary system formed. Thus, CS29497-030 is both an ``r+s'' and ``extrinsic AGB'' star. Furthermore, we find that the mass of the AGB model can be further constrained by the abundance of the light odd-element [Na/Fe] which is sensitive to the neutron excess.

Inese I. Ivans; Christopher Sneden; Roberto Gallino; John J. Cowan; George W. Preston

2005-04-29T23:59:59.000Z

262

0-600 kev Gamma-Ray Spectra from Thermal Neutron Capture in the Region A=104 to 198  

Science Journals Connector (OSTI)

The energies and absolute intensities of prominent peaks in the 0-600 kev region of the gamma-ray spectrum following thermal neutron capture have been measured with a single NaI(Tl) scintillation spectrometer. The elements investigated were rhodium, silver, cadmium, indium, antimony, tellurium, iodine, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, hafnium, tantalum, rhenium, iridium, platinum, and gold.

James E. Draper

1959-04-01T23:59:59.000Z

263

Europium resonance parameters from neutron capture and transmission measurements in the energy range 0.01200 eV  

E-Print Network (OSTI)

Europium resonance parameters from neutron capture and transmission measurements in the energy University. The current measure- ment has better energy resolution and updated analysis methods. Other-yield tail at the high end of the fission fragment mass distribution. Measure- ments have been made

Danon, Yaron

264

Chemical evolution of neutron capture elements in our Galaxy and in the dwarf spheroidal galaxies of the Local Group  

E-Print Network (OSTI)

By adopting a chemical evolution model for the Milky Way already reproducing the evolution of several chemical elements, we compare our theoretical results with accurate and new stellar data of neutron capture elements and we are able to impose strong constraints on the nucleosynthesis of the studied elements. We can suggest the stellar sites of production for each element. In particular, the r-process component of each element (if any) is produced in the mass range from 10 to 30 Msun, whereas the s-process component arises from stars in the range from 1 to 3 Msun. Using the same chemical evolution model, extended to different galactocentric distances, we obtain results on the radial gradients of the Milky Way. We compare the results of the model not only for the neutron capture elements but also for alpha-elements and iron peak elements with new data of Cepheids stars. We give a possible explanation to the considerable scatter of neutron capture elements observed in low metallicity stars in the solar vicinity, compared to the small star to star scatter observed for the alpha-elements. In fact, we have developed a stochastic chemical evolution model, in which the main assumption is a random formation of new stars, subject to the condition that the cumulative mass distribution follows a given initial mass function. With our model we are able to reproduce the different features of neutron capture elements and alpha-elements. Finally, we test the prescriptions for neutron capture elements also for the dwarf spheroidal galaxies of the Local Group. We predict that the chemical evolution of these elements in dwarf spheroidal galaxies is different from the evolution in the solar vicinity and indicates that dwarf spheroidal galaxies (we see nowadays) cannot be the building blocks of our Galaxy.

Gabriele Cescutti

2007-08-30T23:59:59.000Z

265

Search for Redshifted 2.2 MeV Neutron Capture Line From A0535+262 in Outburst  

E-Print Network (OSTI)

The Be/X-ray binary system A0535+262 underwent a giant outburst in May-June 2005, followed by a dimmer outburst in August-September 2005. This increased intensity provided an opportunity to search for redshifted neutron-capture lines from the surface of the neutron star. If discovered, such lines would constrain the neutron star equation of state, providing the motivation of this search. The spectrometer (SPI) on board the INTEGRAL satellite observed the dimmer outburst and provided the data for this research. We have not detected a line with enough significance, with the width-dependent upper limits on the broadened and redshifted neutron capture line in the range of (2 - 11) x 10^(-4) photons cm^(-2) s^(-1). To our knowledge, these are the strongest upper limits on the redshifted 2.2 MeV emission from an accreting neutron star. Our analysis of the transparency of the neutron star surface for 2.2 MeV photons shows that photons have a small but finite chance of leaving the atmosphere unscattered, which diminishes the possibility of detection.

Sirin Caliskan; Emrah Kalemci; Matthew G. Baring; Steven E. Boggs; Peter Kretschmar

2008-12-15T23:59:59.000Z

266

First Measurements of the Inclined Boron Layer Thermal-Neutron Detector for Reflectometry  

SciTech Connect

A prototype detector based on the inclined absorber layer principle is introduced. For the Liquids Reflectometer at the Spallation Neutron Source, it is shown to be a significant improvement over its current detector, which imposes an instantaneous count rate limitation of 50 kcps.

Van Vuure, Thorwald L [ORNL] [ORNL; Clonts, Lloyd G [ORNL] [ORNL; Crow, Lowell [ORNL] [ORNL; Cooper, Ronald G [ORNL] [ORNL; Richards, John D [ORNL] [ORNL; Riedel, Richard A [ORNL] [ORNL; Robertson, Lee [ORNL] [ORNL

2008-01-01T23:59:59.000Z

267

The radiative neutron capture on 2H, 6Li, 7Li, 12C and 13C at astrophysical energies  

E-Print Network (OSTI)

The continued interest to the study of the radiative neutron capture on atomic nuclei is caused, on the one hand, by the important role of this process in the analysis of many fundamental properties of nuclei and nuclear reactions, and, on the other hand, by the wide use of the capture cross section data in the various applications of nuclear physics and nuclear astrophysics, and, also, by the analysis of the processes of primordial nucleosynthesis in the Universe. This review is devoted to description of the results obtained for the processes of the radiative neutron capture at thermal and astrophysical energies on certain light atomic nuclei. The consideration of these processes is done in the frame of the potential cluster model, the general principles of which and calculation methods were described earlier. The methods of usage of the obtained on the basis of the phase shift analysis intercluster potentials will be directly demonstrated for calculations of the radiative capture characteristics. The considered capture reactions are not a part of stellar thermonuclear cycles, but they get in the basic reaction chain of primordial nucleosynthesis, taken place in the time of the Universe formation.

S. B. Dubovichenko; A. V. Dzhazairov-Kakhramanov; N. A. Burkova

2014-01-28T23:59:59.000Z

268

Compositions for boron delivery to mammalian tissue  

DOE Patents (OSTI)

Boron neutron capture therapy can utilize X.sub.y B.sub.20 H.sub.17 L where X is an alkali metal, y is 1 to 4, and L is a two electron donor such as NH.sub.3, and Na.sub.2 B.sub.10 H.sub.9 NCO, among others. These borane salts may be used free or encapsulated in liposomes. Liposomes may also have embedded within their bilayers carboranes to increase the amount of delivered .sup.10 B and/or to increase the tumor specificity of the liposome.

Hawthorne, M. Frederick (Encino, CA); Feaks, Debra Arlene (Los Angeles, CA); Shelly, Kenneth John (Los Angeles, CA)

2001-01-01T23:59:59.000Z

269

ARE THERE ANY STARS LACKING NEUTRON-CAPTURE ELEMENTS? EVIDENCE FROM STRONTIUM AND BARIUM  

SciTech Connect

The cosmic dispersion in the abundances of the heavy elements strontium and barium in halo stars is well known. Strontium and barium are detected in most cool, metal-poor giants, but are these elements always detectable? To identify stars that could be considered probable candidates for lacking these elements, I examine the stellar abundance data available in the literature for 1148 field stars and 226 stars in dwarf galaxies, 776 of which have metallicities lower than [Fe/H] <-2.0. Strontium or barium have been detected in all field, globular cluster, and dwarf galaxy environments studied. All upper limits are consistent with the lowest detected ratios of [Sr/H] and [Ba/H]. The frequent appearance of these elements raises the intriguing prospect that at least one kind of neutron-capture reaction operates as often as the nucleosynthesis mechanisms that produce lighter elements, such as magnesium, calcium, or iron, although the yields of heavy elements may be more variable.

Roederer, Ian U., E-mail: iur@obs.carnegiescience.edu [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2013-01-01T23:59:59.000Z

270

Importance of nuclear triaxiality for electromagnetic strength, level density and neutron capture cross sections in heavy nuclei  

E-Print Network (OSTI)

Cross sections for neutron capture in the range of unresolved resonances are predicted simultaneously to level distances at the neutron threshold for more than 100 spin-0 target nuclei with A >70. Assuming triaxiality in nearly all these nuclei a combined parameterization for both, level density and photon strength is presented. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians adding up to the TRK sum rule and theory-based predictions for the A-dependence of pole energies and spreading widths. For the small spins reached by capture level densities are well described by only one free global parameter; a significant collective enhancement due to the deviation from axial symmetry is observed. Reliable predictions for compound nuclear reactions also outside the valley of stability as expected from the derived global parameterization are important for nuclear astrophysics and for the transmutation of nuclear waste.

Grosse, Eckart; Massarczyk, Ralph

2014-01-01T23:59:59.000Z

271

Importance of nuclear triaxiality for electromagnetic strength, level density and neutron capture cross sections in heavy nuclei  

E-Print Network (OSTI)

Cross sections for neutron capture in the range of unresolved resonances are predicted simultaneously to level distances at the neutron threshold for more than 100 spin-0 target nuclei with A >70. Assuming triaxiality in nearly all these nuclei a combined parameterization for both, level density and photon strength is presented. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians adding up to the TRK sum rule and theory-based predictions for the A-dependence of pole energies and spreading widths. For the small spins reached by capture level densities are well described by only one free global parameter; a significant collective enhancement due to the deviation from axial symmetry is observed. Reliable predictions for compound nuclear reactions also outside the valley of stability as expected from the derived global parameterization are important for nuclear astrophysics and for the transmutation of nuclear waste.

Eckart Grosse; Arnd R. Junghans; Ralph Massarczyk

2014-01-05T23:59:59.000Z

272

Radiative neutron capture on 9be, 14c, 14n, 15n and 16o at thermal and astrophysical energies  

E-Print Network (OSTI)

The total cross sections of the radiative neutron capture processes on 9Be, 14C, 14N, 15N, and 16O are described in the framework of the modified potential cluster model with the classification of orbital states according to Young tableaux. The continued interest in the study of these reactions is due, on the one hand, to the important role played by this process in the analysis of many fundamental properties of nuclei and nuclear reactions, and, on the other hand, to the wide use of the capture cross section data in the various applications of nuclear physics and nuclear astrophysics, and, also, to the importance of the analysis of primordial nucleosynthesis in the Universe. This article is devoted to the description of results for the processes of the radiative neutron capture on certain light atomic nuclei at thermal and astrophysical energies. The considered capture reactions are not part of stellar thermonuclear cycles, but involve in the reaction chains of inhomogeneous Big Bang models.

Sergey Dubovichenko; Albert Dzhazairov-Kakhramanov; Nadezhda Afanasyeva

2014-01-28T23:59:59.000Z

273

Thermal neutron shield and method of manufacture  

DOE Patents (OSTI)

A thermal neutron shield comprising boron shielding panels with a high percentage of the element Boron. The panel is least 46% Boron by weight which maximizes the effectiveness of the shielding against thermal neutrons. The accompanying method discloses the manufacture of boron shielding panels which includes enriching the pre-cursor mixture with varying grit sizes of Boron Carbide.

Metzger, Bert Clayton; Brindza, Paul Daniel

2014-03-04T23:59:59.000Z

274

Europium resonance parameters from neutron capture and transmission measurements in the energy range 0.01–200 eV  

Science Journals Connector (OSTI)

Abstract Europium is a good absorber of neutrons suitable for use as a nuclear reactor control material. It is also a fission product in the low-yield tail at the high end of the fission fragment mass distribution. Measurements have been made of the stable isotopes with natural and enriched samples. The linear electron accelerator center (LINAC) at the Rensselaer Polytechnic Institute (RPI) was used to explore neutron interactions with europium in the energy region from 0.01 to 200 eV. Neutron capture and transmission measurements were performed by the time-of-flight technique. Two transmission measurements were performed at flight paths of 15 and 25 m with 6Li glass scintillation detectors. The neutron capture measurements were performed at a flight path of 25 m with a 16-segment sodium iodide multiplicity detector. Resonance parameters were extracted from the data using the multilevel R-matrix Bayesian code SAMMY. A table of resonance parameters and their uncertainties is presented. To prevent air oxidation metal samples were sealed in airtight aluminum cans in an inert environment. Metal samples of natural europium, 47.8 atom% 151Eu, 52.2 atom% 153Eu, as well as metal samples enriched to 98.77 atom% 153Eu were measured. The measured neutron capture resonance integral for 153Eu is (9.9 ± 0.4)% larger than ENDF/B-VII.1. The capture resonance integral for 151Eu is (7 ± 1)% larger than ENDF/B-VII.1. Another significant finding from these measurements was a significant increase in thermal total cross section for 151Eu, up (9 ± 3)% from ENDF/B-VII.1. The thermal total cross section for 153Eu is down (8 ± 3)% from ENDF/B-VII.1, but it is larger than that of ENDF/B-VII.0. The resolved resonance region has been extended from 100 eV to 200 eV for both naturally-occurring isotopes. Uncertainties in resonance parameters have been propagated from a number of experimental quantities using a Bayesian analysis. Uncertainties have also been estimated from fitting each Eu sample measurement individually.

G. Leinweber; D.P. Barry; J.A. Burke; M.J. Rapp; R.C. Block; Y. Danon; J.A. Geuther; F.J. Saglime III

2014-01-01T23:59:59.000Z

275

Standard guide for establishing surveillance test program for boron-based neutron absorbing material systems for use in nuclear spent fuel storage racks  

E-Print Network (OSTI)

1.1 This guide provides guidance for establishing a surveillance test program to monitor the performance of boron-based neutron absorbing material systems (absorbers) necessary to maintain sub-criticality in nuclear spent fuel storage racks in a pool environment. The practices presented in this guide, when implemented, will provide a comprehensive surveillance test program to verify the presence of sufficient neutron absorbing material within the storage racks. The performance of a surveillance test program provides added assurance of the safe and effective operation of a high-density storage facility for nuclear spent fuel. 1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2007-01-01T23:59:59.000Z

276

E-Print Network 3.0 - arc neutron capture Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Oak Ridge National Laboratory Collection: Materials Science 4 For more information: Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Summary:...

277

Review of the Development and Testing of a New Family of Boron and Gadolinium-Bearing Dual Thermal Neutron Absorbing Alloys - 13026  

SciTech Connect

The development of a new class of Fe-based thermal neutron absorbing alloys (patent pending) containing both natural boron (B) and gadolinium (Gd) is reviewed. Testing has shown that Ar and N inert gas atomized powder metallurgy (PM) variants offer superior processability coupled with improved mechanical properties that exhibit reduced anisotropy and reduced corrosion rates compared to conventional cast/wrought processed material. PM processing results in a microstructure containing a uniform distribution of second phase borides and gadolinides, and the morphology of the gadolinides prevents the formation low melting point Gd-bearing phases at solidifying austenite boundaries. The new T316-based materials containing both B and Gd exhibit superior corrosion resistance compared to straight B-bearing T304 materials. By keeping the B content < 1 weight percent (%) and using Gd to attain an equivalent B (B{sub Eq}) content higher than that achievable through the use of B only, the new materials exhibit superior ductility, toughness and bendability as a result of significantly reduced area fraction of Cr-rich M{sub 2}B borides. Limiting the total area fraction of second phase particles to < 22% insures a product with superior bendability. By restricting B to < 1% and using Gd up to 2.5%, B{sub Eq} levels approaching 12% can be attained that provide a cost effective improvement in thermal neutron absorption capability compared to using B-10 enriched boron. The new materials can be easily bent during fabrication compared to existing metal matrix composite materials while offering similar thermal neutron absorption capability. Production lots containing B{sub Eq} levels of 4.0 and 7.5% (Micro-Melt{sup R} DuoSorb{sup TM} 316NU-40 and 75, respectively) are in the process of being fabricated for customer trial material. (authors)

Schmidt, M.L.; Del Corso, G.J.; Klankowski, K.A. [Carpenter Tech., Corp., P.O. Box 14662, Reading PA 19612-4662 (United States)] [Carpenter Tech., Corp., P.O. Box 14662, Reading PA 19612-4662 (United States); Lherbier, L.W.; Novotnak, D.J. [Carpenter Powder Products, 600 Mayer St., Bridgeville, PA 15017 (United States)] [Carpenter Powder Products, 600 Mayer St., Bridgeville, PA 15017 (United States)

2013-07-01T23:59:59.000Z

278

The Hamster Cheek Pouch as a Model of Oral Cancer for Boron Neutron Capture Therapy Studies: Selective Delivery of Boron by Boronophenylalanine  

Science Journals Connector (OSTI)

...of Buenos Aires, Argentina. 2 To whom requests...National Atomic Energy Commission, Avenida...1429 Buenos Aires, Argentina. Phone: 54-11-6772-7149...National Atomic Energy Commission, 1429 Buenos Aires, Argentina. | Journal Article...

Erica L. Kreimann; Maria E. Itoiz; Alejandra Dagrosa; Ricardo Garavaglia; Silvia Farías; Daniel Batistoni; and Amanda E. Schwint

2001-12-15T23:59:59.000Z

279

Folate receptor-mediated boron-10 containing carbon nanoparticles as potential delivery vehicles for boron neutron capture therapy of nonfunctional pituitary adenomas  

Science Journals Connector (OSTI)

Invasive nonfunctional pituitary adenomas (NFPAs) are difficult to completely resect and often develop tumor recurrence after initial surgery. Currently, no medications are clinically effective in the control of ...

CongXin Dai; Feng Cai; Kuo Chu Hwang; YongMao Zhou…

2013-02-01T23:59:59.000Z

280

>18F-labeled BPA positron emmision tomography (PET) based Boron Neutron Capture Therapy on malignant glioma patients in Japan  

Science Journals Connector (OSTI)

...Development, Sep 12-15, 2006 18F-labeled BPA positron emmision tomography (PET) based...borocaptate (BSH) and boronophenylalanine (BPA), both of which have been used clinically...at Osaka Medical College.18F-labeled BPA positron emmision tomography (BPA-PET...

Shinji Kawabata; Shin-Ichi Miyatake; Minoru Miyashita; Atsushi Doi; Kyouko Iida; Toshihiko Kuroiwa; Yoshio Imahori; Koji Ono

2006-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Neutron capture cross sections of /sup 178/,/sup 179/,/sup 180/Hf and the origin of nature's rarest stable isotope /sup 180/Ta  

SciTech Connect

The neutron capture cross sections of /sup 178/,/sup 179/,/sup 180/Hf were measured in the energy range 2.6 keV to 2 MeV. The average capture cross sections were derived and fitted in terms of strength functions. Resonance parameters for the observed resonances below 10 keV were determined by shape analysis. Maxwellian-averaged capture cross sections were computed for thermal energies with kT between 5 and 100 keV. The cross sections for kT = 30 keV were used to determine the population probability of the 8- isomeric level in /sup 180/Hf by neutron capture as (1.24 +- 0.06)% and the r-process abundance of /sup 180/Hf as 0.0290 (Si = 10/sup 6/). These quantities served to analyze s- and r-process nucleosynthesis of /sup 180/Ta, nature's rarest stable isotope.

Beer, H.; Macklin, R.L.

1982-01-01T23:59:59.000Z

282

Effect of boron and gadolinium concentration on the calculated neutron multiplication factor of U(3)O/sub 2/ fuel pins in optimum geometries  

SciTech Connect

The KENO-Va improved Monte Carlo criticality program is used to calculate the neutron multiplication factor for TMI-U2 fuel compositions in a variety of configurations and to display parametric regions giving rise to maximum reactivity contributions. The lattice pitch of UO/sub 2/ fuel pins producing a maximum k/sub eff/ is determined as a function of boron concentrations in the coolant for infinite and finite systems. The characteristics of U/sub 3/O/sub 8/-coolant mixtures of interest to modeling the rubble region of the core are presented. Several disrupted core configurations are calculated and comparisons made. The results should be useful to proposed defueling of the TMI-U2 reactor.

Thomas, J.T.

1984-10-01T23:59:59.000Z

283

Principle and Uncertainty Quantification of an Experiment Designed to Infer Actinide Neutron Capture Cross-Sections  

SciTech Connect

An integral reactor physics experiment devoted to infer higher actinide (Am, Cm, Bk, Cf) neutron cross sections will take place in the US. This report presents the principle of the planned experiment as well as a first exercise aiming at quantifying the uncertainties related to the inferred quantities. It has been funded in part by the DOE Office of Science in the framework of the Recovery Act and has been given the name MANTRA for Measurement of Actinides Neutron TRAnsmutation. The principle is to irradiate different pure actinide samples in a test reactor like INL’s Advanced Test Reactor, and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after neutron irradiation allows the energy integrated neutron cross-sections to be inferred since the relation between the two are the well-known neutron-induced transmutation equations. This approach has been used in the past and the principal novelty of this experiment is that the atom densities of the different transmutation products will be determined with the Accelerator Mass Spectroscopy (AMS) facility located at ANL. While AMS facilities traditionally have been limited to the assay of low-to-medium atomic mass materials, i.e., A < 100, there has been recent progress in extending AMS to heavier isotopes – even to A > 200. The detection limit of AMS being orders of magnitude lower than that of standard mass spectroscopy techniques, more transmutation products could be measured and, potentially, more cross-sections could be inferred from the irradiation of a single sample. Furthermore, measurements will be carried out at the INL using more standard methods in order to have another set of totally uncorrelated information.

G. Youinou; G. Palmiotti; M. Salvatorre; G. Imel; R. Pardo; F. Kondev; M. Paul

2010-01-01T23:59:59.000Z

284

Neutron capture in low mass Asymptotic Giant Branch stars: cross sections and abundance signatures  

E-Print Network (OSTI)

The recently improved information on the stellar (n,gamma) cross sections of neutron-magic nuclei at N = 82, and in particular of 142Nd, turned out to represent a sensitive test for models of s-process nucleosynthesis. While these data were found to be incompatible with the classical approach based on an exponential distribution of neutron exposures, they provide significantly better agreement between the solar abundance distribution of s nuclei and the predictions of models for low mass AGB stars. Particular attention is paid to a consistent description of s-process branchings in the region of the rare earth elements. It is shown that - in certain cases - the nuclear data are sufficiently accurate that the resulting abundance uncertainties can be completely attributed to stellar modelling. Thus, the s process becomes important for testing the role of different stellar masses and metallicities as well as for constraining the assumptions for describing the low neutron density provided by the 13C source.

C. Arlandini; F. Kaeppeler; K. Wisshak; R. Gallino; M. Lugaro; M. Busso; O. Straniero

1999-06-16T23:59:59.000Z

285

Capture of a neutron to excited states of a {sup 9}Be nucleus taking into account resonance at 622 keV  

SciTech Connect

Radiative capture of a neutron to the ground and excited states of the 9Be nucleus is considered using the potential cluster model with forbidden states and with classification of cluster states by the Young schemes taking into account resonance at 622 keV for thermal and astrophysical energies.

Dubovichenko, S. B., E-mail: dubovichenko@gmail.com [National Space Agency of the Republic of Kazakhstan, Fessenkov Astrophysical Institute, National Space Research and Technologies Center (Kazakhstan)

2013-10-15T23:59:59.000Z

286

Investigation for the puzzling abundance pattern of the neutron-capture elements in the ultra metal-poor star: CS 30322-023  

E-Print Network (OSTI)

The s-enhanced and very metal-poor star CS 30322-023 shows a puzzling abundance pattern of the neutron-capture elements, i.e. several neutron-capture elements such as Ba, Pb etc. show enhancement, but other neutron-capture elements such as Sr, Eu etc. exhibit deficient with respect to iron. The study to this sample star could make people gain a better understanding of s- and r-process nucleosynthesis at low metallicity. Using a parametric model, we find that the abundance pattern of the neutron-capture elements could be best explained by a star that was polluted by an AGB star and the CS 30322-023 binary system formed in a molecular cloud which had never been polluted by r-process material. The lack of r-process material also indicates that the AGB companion cannot have undergone a type-1.5 supernova, and thus must have had an initial mass below 4.0M$_\\odot$, while the strong N overabundance and the absence of a strong C overabundance indicate that the companion's initial mass was larger than 2.0M$_\\odot$. The smaller s-process component coefficient of this star illustrates that there is less accreted material of this star from the AGB companion, and the sample star should be formed in the binary system with larger initial orbital separation where the accretion-induced collapse (AIC) mechanism can not work.

W. Y. Cui; B. Zhang; K. Ma; L. Zhang

2007-02-26T23:59:59.000Z

287

Thermal neutron capture cross-section to {sup 113}Cd isomer for the study of s-process origin of {sup 115}Sn  

SciTech Connect

The astrophysical origin of a p-nucleus {sup 115}Sn has remained still an open question. The nucleus {sup 115}Sn may be produced by a weak branch of the s-process through a beta-unstable isomer in {sup 113}Cd. However, a neutron capture cross-section to this isomer has not been measured with high accuracy at any energy. A neutron capture cross-section for the {sup 112}Cd(n,gamma){sup 113}Cd{sup m} reaction has been measured with neutrons provided from a nuclear reactor. The nucleus {sup 115}Sn may be produced by a nucleosynthesis flow through {sup 113}Cd{sup m} in the s-process. We have obtained the thermal neutron capture cross-section of 0.028+-0.009[b] and the resonance integral of 1.1+-0.3[b] using a cadmium difference method. The cross-section ratio of the isomer to the ground state has been calculated as a function of the incident neutron energy, E, by using a statistical model. The calculated ratios are almost constant over a wide range of E<100 keV. We have evaluated the s-process contribution to the solar abundance of {sup 115}Sn using the classical steady-flow model. This calculated result has shown that the production through {sup 113}Cd{sup m} may be minor contribution to {sup 115}Sn.

Hayakawa, Takehito; Shizuma, Toshiyuki [Kansai Photon Science Institute, Japan Atomic Energy Agency, Kizu, Kyoto 619-0215 (Japan); Chiba, Satoshi; Hatsukawa, Yuichi; Iwamoto, Nobuyuki; Shinohara, Nobuo; Harada, Hideo [Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Kajino, Toshitaka [National Astronomical Observatory, Osawa, Mitaka, Tokyo 181-8588 (Japan)

2010-06-01T23:59:59.000Z

288

THE WEAK s-PROCESS IN MASSIVE STARS AND ITS DEPENDENCE ON THE NEUTRON CAPTURE CROSS SECTIONS  

SciTech Connect

The slow neutron capture process in massive stars (weak s process) produces most of the s-process isotopes between iron and strontium. Neutrons are provided by the {sup 22}Ne(alpha,n){sup 25}Mg reaction, which is activated at the end of the convective He-burning core and in the subsequent convective C-burning shell. The s-process-rich material in the supernova ejecta carries the signature of these two phases. In the past years, new measurements of neutron capture cross sections of isotopes beyond iron significantly changed the predicted weak s-process distribution. The reason is that the variation of the Maxwellian-averaged cross sections (MACS) is propagated to heavier isotopes along the s path. In the light of these results, we present updated nucleosynthesis calculations for a 25 M{sub sun} star of Population I (solar metallicity) in convective He-burning core and convective C-burning shell conditions. In comparison with previous simulations based on the Bao et al. compilation, the new measurement of neutron capture cross sections leads to an increase of s-process yields from nickel up to selenium. The variation of the cross section of one isotope along the s-process path is propagated to heavier isotopes, where the propagation efficiency is higher for low cross sections. New {sup 74}Ge, {sup 75}As, and {sup 78}Se MACS result in a higher production of germanium, arsenic, and selenium, thereby reducing the s-process yields of heavier elements by propagation. Results are reported for the He core and for the C shell. In shell C-burning, the s-process nucleosynthesis is more uncertain than in the He core, due to higher MACS uncertainties at higher temperatures. We also analyze the impact of using the new lower solar abundances for CNO isotopes on the s-process predictions, where CNO is the source of {sup 22}Ne, and we show that beyond Zn this is affecting the s-process yields more than nuclear or stellar model uncertainties considered in this paper. In particular, using the new updated initial composition, we obtain a high s-process production (overproduction higher than {sup 16}O, {approx}100) for Cu, Ga, Ge, and As. Using the older abundances by Anders and Grevesse, also Se, Br, Kr, and Rb are efficiently produced. Our results have important implications in explaining the origin of copper in the solar abundance distribution, pointing to a prevailing contribution from the weak s-process in agreement with spectroscopic observations and Galactic chemical evolution calculations. Because of the improvement due to the new MACS for nickel and copper isotopes, the nucleosynthesis of copper is less affected by nuclear uncertainties compared to heavier s-process elements. An experimental determination of the {sup 63}Ni MACS is required for a further improvement of the abundance prediction of copper. The available spectroscopic observations of germanium and gallium in stars are also discussed, where most of the cosmic abundances of these elements derives from the s-process in massive stars.

Pignatari, M.; Herwig, F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P5C2 Canada (Canada); Gallino, R.; Bisterzo, S. [Dipartimento di Fisica Generale, Universita di Torino, Via Pietro Giuria 1, Torino 10125 (Italy); Heil, M. [Gesellschaft fuer Schwerionenforschung (GSI), D-64291 Darmstadt (Germany); Wiescher, M. [Joint Institute for Nuclear Astrophysics, University of Notre Dame, Notre Dame, IN 46556 (United States); Kaeppeler, F., E-mail: marcop@uvic.c [Forschungszentrum Karlsruhe, Institut fuer Kernphysik, Postfach 3640, 76021 Karlsruhe (Germany)

2010-02-20T23:59:59.000Z

289

Boron determinations in pressure vessel steels  

SciTech Connect

Several studies have suggested that low-energy neutrons contribute to reactor pressure vessel (PV) embrittlement through interactions with boron impurities in the steel. Until now, the available information on boron contents in pressure vessel steels has been based on nominal concentrations or estimates provided by the materials manufacturers. To help resolve the question of boron contribution to PV steel embrittlement, samples of 38 different PV steels were analyzed by high-sensitivity gas mass spectrometry for their helium and boron contents. The boron contents were determined by measuring the increase in helium content in each material as a result of additional thermal neutron exposure. The results of these analyses showed natural boron contents that ranged from 0.23 to 5.11 wt. ppm in the various alloys.

Oliver, B.M. [Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.; McElroy, W.N. [Consultants and Technology Services, Richland, WA (United States); Kellogg, L.S. [Battelle-Pacific Northwest Lab., Richland, WA (United States); Farrar, H. IV

1994-12-31T23:59:59.000Z

290

A Monte Carlo study of the effect of coded-aperture material and thickness on neutron imaging  

Science Journals Connector (OSTI)

......best efficiency in the simulations as pure element due to the expense. It is therefore more likely a system utilising boron-10 or cadmium would be used. This would give a saving on the cost whilst keeping the neutron capture cross section high......

S. C. Hayes; K. A. A. Gamage

2014-10-01T23:59:59.000Z

291

Prompt gamma-ray neutron activation analysis methodology for determination of boron from trace to major contents  

Science Journals Connector (OSTI)

Prompt gamma ray neutron activation analysis (PGNAA) is an isotope specific online nuclear analytical technique for non-destructive determination of elements in diverse matrices [1–5...]. Though in principle all ...

R. Acharya

2009-08-01T23:59:59.000Z

292

An Accelerator Neutron Source for BNCT  

SciTech Connect

The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were 1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, 2) that the patient treatment time be reasonable, 3) that the proton current required to treat patients in reasonable times be technologially achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally 4) that the treatment be safe for the patients.

Blue, Thomas, E

2006-03-14T23:59:59.000Z

293

The Harwell Neutron Project  

Science Journals Connector (OSTI)

... 2 cm. thick, placed on three sides of the neutron booster. A layer of boron-10 metal placed between these tanks and the uranium-235 core prevents return of slow neutrons ...

M. J. POOLE; E. R. RAE

1960-01-30T23:59:59.000Z

294

Measurement of the energy, multiplicity and angular correlation of ?-rays from the thermal neutron capture reaction Gd(n, ?) using JPARC-ANNRI  

SciTech Connect

We conducted an experiment using the JPARC-ANNRI spectrometer to measure the energy, multiplicity and correlation of ?-rays from the neutron capture of natural gadolinium. We incorporated the GEANT4 Monte Carlo (MC) simulation into the detector, and compared the data with the results of the MC simulation. We report our data analysis and compare our data with those obtained by the MC simulation.

Ou, Iwa; Yamada, Yoshiyuki; Yano, Takatomi; Mori, Takaaki; Kayano, Tsubasa; Sakuda, Makoto [Department of Physics, Okayama University, Okayama, 700-8530 (Japan); Kimura, Atsushi; Harada, Hideo [Japan Atomic Energy Agency, 2-4 Shirakata Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan)

2014-05-02T23:59:59.000Z

295

Electroextraction of boron from boron carbide scrap  

SciTech Connect

Studies were carried out to extract elemental boron from boron carbide scrap. The physicochemical nature of boron obtained through this process was examined by characterizing its chemical purity, specific surface area, size distribution of particles and X-ray crystallite size. The microstructural characteristics of the extracted boron powder were analyzed by using scanning electron microscopy and transmission electron microscopy. Raman spectroscopic examination of boron powder was also carried out to determine its crystalline form. Oxygen and carbon were found to be the major impurities in boron. Boron powder of purity ? 92 wt. % could be produced by the electroextraction process developed in this study. Optimized method could be used for the recovery of enriched boron ({sup 10}B > 20 at. %) from boron carbide scrap generated during the production of boron carbide. - Highlights: • Recovery of {sup 10}B from nuclear grade boron carbide scrap • Development of process flow sheet • Physicochemical characterization of electroextracted boron • Microscopic examination of electroextracted boron.

Jain, Ashish [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – 603102 (India); Anthonysamy, S., E-mail: sas@igcar.gov.in [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – 603102 (India); Ghosh, C. [Physical Metallurgy Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – 603102 (India); Ravindran, T.R. [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – 603102 (India); Divakar, R.; Mohandas, E. [Physical Metallurgy Group, Indira Gandhi Centre for Atomic Research, Kalpakkam – 603102 (India)

2013-10-15T23:59:59.000Z

296

Boron-10 Lined Proportional Counter Wall Effects  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a boron-lined proportional tube based system in the configuration of a coincidence counter. This report provides information about how variations in proportional counter radius and gas pressure in a typical coincident counter design might affect the observed signal from boron-lined tubes. A discussion comparing tubes to parallel plate counters is also included.

Siciliano, Edward R.; Kouzes, Richard T.

2012-05-01T23:59:59.000Z

297

Boron-Loaded Silicone Rubber Scintillators  

SciTech Connect

Silicone rubber received attention as an alternative to polyvinyltoluene in applications in which the scintillator is exposed to high doses because of the increased resistance of the rubber to the formation of blue-absorbing color centers. Work by Bowen, et al., and Harmon, et al., demonstrated their properties under gamma/x-ray irradiation, and Bell, et al. have shown their response to thermal neutrons. This last work, however, provided an example of a silicone in which both the boron and the scintillator were contained in the rubber as solutes, a formulation which led to the precipitation of solids and sublimation of the boron component. In the present work we describe a scintillator in which the boron is chemically bonded to the siloxane and so avoids the problem of precipitation and loss of boron to sublimation. Material containing up to 18% boron, by weight, was prepared, mounted on photomultipliers, and exposed to both neutron and gamma fluxes. Pulse height spectra showing the neutron and photon response were obtained, and although the light output was found to be much poorer than from samples in which boron was dissolved, the higher boron concentrations enabled essentially 100% neutron absorption in only a few millimeters' thickness of rubber.

Bell, Z.W.; Maya, L.; Brown, G.M.; Sloop, F.V.Jr

2003-05-12T23:59:59.000Z

298

NEUTRON CAPTURE CROSS SECTION TO {sup 113}Cd ISOMER AND s-PROCESS CONTRIBUTION TO RARE p-NUCLIDE {sup 115}Sn  

SciTech Connect

A neutron capture cross section for the {sup 112}Cd(n, gamma){sup 113}Cd{sup m} reaction has been measured with neutrons provided from a nuclear reactor in order to study the astrophysical origin of a rare p-process isotope {sup 115}Sn, which may be produced by a nucleosynthesis flow through {sup 113}Cd{sup m} in the s-process. We have obtained the thermal neutron capture cross section of 0.028 +- 0.009 [b] and the resonance integral of 1.1 +- 0.3 [b] using a cadmium difference method. The cross section ratio of the isomer to the ground state has been calculated as a function of the incident neutron energy, E, by using a statistical model. The calculated ratios are almost constant over a wide range of E < 100 keV. We have evaluated the s-process contribution to the solar abundance of {sup 115}Sn using the classical steady-flow model with various astrophysical parameters. This calculated result has shown that the production through {sup 113}Cd{sup m} may give minor contribution to {sup 115}Sn.

Hayakawa, T.; Shizuma, T. [Advanced Photon Research Center, Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan); Chiba, S.; Kajino, T. [National Astronomical Observatory, Mitaka, Tokyo 181-8588 (Japan); Hatsukawa, Y.; Iwamoto, N.; Shinohara, N.; Harada, H. [Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)

2009-12-20T23:59:59.000Z

299

Analytical techniques for boron and boron 10 analysis in a solid experimental tumor EO. 771  

Science Journals Connector (OSTI)

If a tumor can be preferentially loaded with a suitable boron-10 compound and irradiated with thermal neutrons, malignant...?-particle + Li 7-nucleus from the reaction10B(n,?)7Li.

W. Porschen; J. Marx; F. Dallacker; H. Mückter…

1987-01-01T23:59:59.000Z

300

Neutron Detection with Mercuric Iodide  

SciTech Connect

Mercuric iodide is a high-density, high-Z semiconducting material useful for gamma ray detection. This makes it convertible to a thermal neutron detector by covering it with a boron rich material and detecting the 478 keV gamma rays resulting from the {sup 10}B(n, {alpha}){sup 7}Li* reaction. However, the 374 barn thermal capture cross section of {sup nat}Hg, makes the detector itself an attractive absorber, and this has been exploited previously. Since previous work indicates that there are no low-energy gamma rays emitted in coincidence with the 368 keV capture gamma from the dominant {sup 199}Hg(n, {gamma}){sup 200}Hg reaction, only the 368 keV capture gamma is seen with any efficiency a relatively thin (few mm) detector. In this paper we report preliminary measurements of neutrons via capture reactions in a bare mercuric iodide crystal and a crystal covered in {sup 10}B-loaded epoxy. The covered detector is an improvement over the bare detector because the presence of both the 478 and 368 keV gamma rays removes the ambiguity associated with the observation of only one of them. Pulse height spectra, obtained with and without lead and cadmium absorbers, showed the expected gamma rays and demonstrated that they were caused by neutrons.

Bell, Z.A.

2003-06-17T23:59:59.000Z

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to obtain the most current and comprehensive results.


301

High-Resolution Neutron Capture and Total Cross-Section Measurements, and the Astrophysical 95Mo(n,gamma) Reaction Rate at s-process Temperatures  

E-Print Network (OSTI)

Abundances of Mo isotopes predicted by stellar models of the s process are, except for 95Mo, in good agreement with data from single grains of mainstream presolar SiC. Because the meteorite data seemed sound and no reasonable modification to stellar theory resulted in good agreement for 95Mo, it has been suggested that the recommended neutron capture reaction rate for this nuclide is 30% too low. Therefore, we have made a new determination of the 95Mo(n,gamma) reaction rate via high-resolution measurements of the neutron-capture and total cross sections of 95Mo at the Oak Ridge Electron Linear Accelerator. These data were analyzed with the R-matrix code SAMMY to obtain parameters for resonances up to En = 10 keV. Also, a small change to our capture apparatus allowed us to employ a new technique to vastly improve resonance spin and parity assignments. These new resonance parameters, together with our data in the unresolved range, were used to calculate the 95Mo(n,gamma) reaction rate at s-process temperatures. We compare the currently recommended rate to our new results and discuss their astrophysical impact.

P. E. Koehler; J. A. Harvey; K. H. Guber; D. Wiarda

2008-09-16T23:59:59.000Z

302

Measurement of the neutron capture cross section of the s-only isotope 204Pb from 1 eV to 440 keV  

E-Print Network (OSTI)

The neutron capture cross section of 204Pb has been measured at the CERN n_TOF installation with high resolution in the energy range from 1 eV to 440 keV. An R-matrix analysis of the resolved resonance region, between 1 eV and 100 keV, was carried out using the SAMMY code. In the interval between 100 keV and 440 keV we report the average capture cross section. The background in the entire neutron energy range could be reliably determined from the measurement of a 208Pb sample. Other systematic effects in this measurement could be investigated and precisely corrected by means of detailed Monte Carlo simulations. We obtain a Maxwellian average capture cross section for 204Pb at kT=30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at kT=5 keV is about 35% larger than the values reported so far. The implications of the new cross section for the s-process abundance contributions in the Pb/Bi region are discussed.

C. Domingo-Pardo

2006-10-24T23:59:59.000Z

303

Cyclotron-based neutron source for BNCT  

SciTech Connect

Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation and treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8 Multiplication-Sign 109 neutrons/cm{sup 2}/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with {sup 10}B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K. [Sumitomo Heavy Industries, Ltd (Japan); Tanaka, H.; Sakurai, Y.; Maruhashi, A. [Kyoto University Research Reactor Institute (Japan)

2013-04-19T23:59:59.000Z

304

Boron-10 ABUNCL Active Testing  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report provides results from testing of the active mode of the General Electric Reuter-Stokes Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) at Los Alamos National Laboratory using sources and fuel pins.

Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.

2013-07-09T23:59:59.000Z

305

The Chemical Composition of Carbon-Rich, Very Metal-Poor Stars: A New Class of Mildly Carbon-Rich Objects Without Excess of Neutron-Capture Elements  

E-Print Network (OSTI)

We report on an analysis of the chemical composition of five carbon-rich, very metal-poor stars based on high-resolution spectra. One star, CS22948-027, exhibits very large overabundances of carbon, nitrogen, and the neutron-capture elements, as found in the previous study of Hill et al.. This result may be interpreted as a consequence of mass transfer from a binary companion that previously evolved through the asymptotic giant branch stage. By way of contrast, the other four stars we investigate exhibit no overabundances of barium ([Ba/Fe]carbon and/or nitrogen ([C+N]+1). We have been unable to determine accurate carbon and nitrogen abundances for the remaining star (CS30312-100). These stars are rather similar to the carbon-rich, neutron-capture-element-poor star CS22957-027 discussed previously by Norris et al., though the carbon overabundance in this object is significantly larger ([C/Fe]=+2.2). Our results imply that these carbon-rich objects with ``normal'' neutron-capture element abundances are not rare among very metal-deficient stars. One possible process to explain this phenomenon is as a result of helium shell flashes near the base of the AGB in very low-metallicity, low-mass (M~carbon enhancements reported herein ([C/Fe]+1) are similar to those reported in the famous r-process-enhanced star CS22892-052. We discuss the possibility that the same process might be responsible for this similarity, as well as the implication that a completely independent phenomenon was responsible for the large r-process enhancement in CS22892-052.

Wako Aoki; John E. Norris; Sean G. Ryan; Timothy C. Beers; Hiroyasu Ando

2001-11-15T23:59:59.000Z

306

Determination of the properties of nuclear energy levels of La¹³? and Pr¹?¹ by the resonance fluorescence of neutron capture gamma rays  

E-Print Network (OSTI)

DE ERMINATION OF THE PROPERTIES OF NUCLEAR ENEPGY LEVELS OF La~ AND Pr-"' BY THE RESCNANCE FLUORESCENCE CF Ni". UTRON CAPTURE BAI'IMA RAYS A Thesis William Bradley Wilson Submitted to the Graduate College of Texas ASM University in partial... fulfil'men o. the reouirement for ti. e degr e of Master of Science January, 1969 MaJ'or Sub) ect Nuclea Eng. '. u:eering DE' EPM1INATION OF THE PROPERTIES OF NUCLEAR ENERGY LEVELS OF La ~ AND Pr'" BY THE RFSONANCE FLUORESCENCE OF NEUTRON CAP URE...

Wilson, William Bradley

2012-06-07T23:59:59.000Z

307

Direct current sputtering of boron from boron/boron mixtures  

DOE Patents (OSTI)

A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached; and, coating the substrate material with boron by sputtering from the boron-containing rod. 2 figures.

Timberlake, J.R.; Manos, D.; Nartowitz, E.

1994-12-13T23:59:59.000Z

308

Report to the DOE nuclear data committee. [EV RANGE 10-100; CROSS SECTIONS; PHOTONEUTRONS; NEUTRONS; GAMMA RADIATION; COUPLED CHANNEL THEORY; DIFFERENTIAL CROSS SECTIONS; MEV RANGE 01-10; ; CAPTURE; GAMMA SPECTRA; THERMAL NEUTRONS; COMPUTER CALCULATIONS; DECAY; FISSION PRODUCTS; FISSION YIELD; SHELL MODELS; NUCLEAR DATA COLLECTIONS  

SciTech Connect

Topics covered include: studies of (n, charged particle) reactions with 14 to 15 MeV neutrons; photoneutron cross sections for /sup 15/N; neutron radiative capture; Lane-model analysis of (p,p) and (n,n) scattering on the even tin isotopes; neutron scattering cross sections for /sup 181/Ta, /sup 197/Au, /sup 209/Bi, /sup 232/Th, and /sup 238/U inferred from proton scattering and charge exchange cross sections; neutron-induced fission cross sections of /sup 245/Cm and /sup 242/Am; fission neutron multiplicities for /sup 245/Cm and /sup 242/Am; the transport of 14 MeV neutrons through heavy materials 150 < A < 208; /sup 249/Cm energy levels from measurement of thermal neutron capture gamma rays; /sup 231/Th energy levels from neutron capture gamma ray and conversion electron spectroscopy; new measurements of conversion electron binding energies in berkelium and californium; nuclear level densities; relative importance of statistical vs. valence neutron capture in the mass-90 region; determination of properties of short-lived fission products; fission yield of /sup 87/Br and /sup 137/I from 15 nuclei ranging from /sup 232/Th to /sup 249/Cf; evaluation of charged particle data for the ECPL library; evaluation of secondary charged-particle energy and angular distributions for ENDL; and evaluated nuclear structure libraries derived from the table of isotopes. (GHT)

Struble, G.L.; Haight, R.C.

1981-03-01T23:59:59.000Z

309

In vitro biological effectiveness of JRR-4 epithermal neutron beam. Experiment under free air beam and in water phantom. Cooperative research  

E-Print Network (OSTI)

The surviving curve and the biological effectiveness factor of dose components generated in boron neutron capture therapy (BNCT) were separately determined in neutron beams at Japan Research Reactor No.4. Surviving fraction of V79 Chinese hamster cell with or without sup 1 sup 0 B was obtained using an epithermal neutron beam (ENB), a mixed thermal-epithermal neutron beam (TNB-1), and a thermal neutron beam (TNB-2), which were used or planned to use for BNCT clinical trial. The cell killing effect of these neutron beams with or without the presence of sup 1 sup 0 B depended highly on the neutron beam used, according to the epithermal and fast neutron content in the beam. The biological effectiveness factor values of the boron capture reaction for ENB, TNB-1 and TNB-2 were 3.99+-0.24, 3.04+-0.19 and 1.43+-0.08, respectively. The biological effectiveness factor values of the high-LET dose components based on the hydrogen recoils and the nitrogen capture reaction were 2.50+-0.32, 2.34+-0.30 and 2.17+-0.28 for EN...

Yamamoto, T; Horiguchi, Y; Kishi, T; Kumada, H; Matsumura, A; Nose, T; Torii, Y; Yamamoto, K

2002-01-01T23:59:59.000Z

310

Carbon-Enhanced Metal-Poor Stars. Osmium and Iridium Abundances in the Neutron-Capture-Enhanced Subgiants CS31062-050 and LP625-44  

E-Print Network (OSTI)

We have investigated the abundances of heavy neutron-capture elements, including osmium (Os) and iridium (Ir), in the two Carbon-Enhanced Metal-Poor (CEMP) subgiants CS31062-050 and LP625-44. CS31062-050 is known to be a so-called CEMP-r/s star, which exhibits large excesses of s-process elements such as barium (Ba) and lead (Pb), as well as a significant enhancement of europium (Eu) that cannot be explained by conventional s-process production in Asymptotic Giant Branch star models. Our analysis of the high-resolution spectrum for this object has determined, for the first time, the abundances of Ir and Os, elements in the third peak of the r-process nucleosynthesis. They also exhibit significant excesses relative to the predictions of standard s-process calculations. These two elements are not detected in a similar-quality spectrum of LP625-44; the derived upper limits on their abundances are lower than the abundances in CS31062-050. We compare the observed abundance patterns of neutron-capture elements, including Os and Ir, in these two stars with recent model calculations of the s-process, and discuss possible interpretations.

Wako Aoki; Sara Bisterzo; Roberto Gallino; Timothy C. Beers; John E. Norris; Sean G. Ryan; Stelios Tsangarides

2006-09-06T23:59:59.000Z

311

Boron-10 Lined Proportional Counter Model Validation  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards (NA-241) is supporting the project “Coincidence Counting With Boron-Based Alternative Neutron Detection Technology” at Pacific Northwest National Laboratory (PNNL) for the development of an alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a boron-lined proportional tube-based alternative system in the configuration of a coincidence counter. This report discusses the validation studies performed to establish the degree of accuracy of the computer modeling methods current used to simulate the response of boron-lined tubes. This is the precursor to developing models for the uranium neutron coincidence collar under Task 2 of this project.

Lintereur, Azaree T.; Siciliano, Edward R.; Kouzes, Richard T.

2012-06-30T23:59:59.000Z

312

Characteristics of Some Radionuclides of Tungsten, Rhenium, and Osmium Formed by Second-Order Thermal Neutron Capture  

Science Journals Connector (OSTI)

The identification and characteristics of several beta-emitting nuclides are reported. The half-life of W188 is 65 days, Os194 about 700 days, while Re189 might be either of two isotopes having half-lives of about 150 days or of at least five years. The mass assignment of W181 has been confirmed in view of its presence in thermal-neutron irradiated tungsten. Re188 was found to have a half-life of 16.9 hours. No gamma-radiation could be found by absorption measurements to be associated with the 18-hour Ir194 daughter of Os194. Thermal-neutron activation cross sections are reported for most of the nuclides.

Manfred Lindner

1951-10-15T23:59:59.000Z

313

Abstract 2676: Feasible evaluation of neutron capture therapy for local recurrenced breast cancer according to boron uptake in tumour with estimating by F-BPA positron emission tomograpy  

Science Journals Connector (OSTI)

...Abstract IA13: Chemicals in the environment: BPA and other worries. Gail S. Prins University...estradiol or the endocrtine disruptor bisphenol A (BPA) over a range of doses (0.1 to 5,000 ug BPA/kg BW) increases susceptibility of the adult...

Hironobu Yanagie; Hiroyuki Takahashi; Yoshitaka Furuya; Hiroaki Kumada; Takemi Nakamura; Hironori Horiguchi; Hirotaka Sugiyama; Koji Ono; Minoru Ono; Masazumi Eriguchi

2011-07-12T23:59:59.000Z

314

Boron nitride nanotubes  

DOE Patents (OSTI)

Boron nitride nanotubes are prepared by a process which includes: (a) creating a source of boron vapor; (b) mixing the boron vapor with nitrogen gas so that a mixture of boron vapor and nitrogen gas is present at a nucleation site, which is a surface, the nitrogen gas being provided at a pressure elevated above atmospheric, e.g., from greater than about 2 atmospheres up to about 250 atmospheres; and (c) harvesting boron nitride nanotubes, which are formed at the nucleation site.

Smith, Michael W. (Newport News, VA); Jordan, Kevin (Newport News, VA); Park, Cheol (Yorktown, VA)

2012-06-06T23:59:59.000Z

315

Neutron Radiative Capture Cross Section of {sup 232}Th in the Energy Range from 0.06 to 2 MeV  

SciTech Connect

The neutron capture cross section of {sup 232}Th has been measured relative to {sigma}(n, {gamma}) for {sup 197}Au and {sigma}(n,f) for {sup 235}U in the energy range from 60 keV to 2 MeV. Neutrons were produced by the {sup 7}Li(p,n) and T(p,n) reactions at the 4-MV Van de Graaff Accelerator of CEN Bordeaux-Gradignan. The activation technique was used, and the cross section was measured relative to the {sup 197}Au(n,{gamma}) standard cross section up to 1 MeV. The characteristic gamma lines of the product nuclei {sup 233}Pa and {sup 198}Au were measured with a 40% high-purity germanium detector. Above this energy, the reaction {sup 235}U(n,f) was also used as a second standard, and the fission fragments were detected with a photovoltaic cell. The results, after applying the appropriate corrections, indicate that the cross sections are close to the JENDL-3 database values up to 800 keV and over 1.4 MeV. For energies in the intermediate range, our values are slightly lower than those from all the libraries.

Karamanis, D. [CEN Bordeaux-Gradignan (France); Petit, M. [CEN Bordeaux-Gradignan (France); Andriamonje, S. [CEN Bordeaux-Gradignan (France); Barreau, G. [CEN Bordeaux-Gradignan (France); Bercion, M. [CEN Bordeaux-Gradignan (France); Billebaud, A. [ISN Grenoble (France); Blank, B. [CEN Bordeaux-Gradignan (France); Czajkowski, S. [CEN Bordeaux-Gradignan (France); Moral, R. del [CEN Bordeaux-Gradignan (France); Giovinazzo, J. [CEN Bordeaux-Gradignan (France); Lacoste, V. [CERN (Switzerland); Marchand, C. [CEN Bordeaux-Gradignan (France); Perrot, L. [ISN Grenoble (France); Pravikoff, M. [CEN Bordeaux-Gradignan (France); Thomas, J.C. [CEN Bordeaux-Gradignan (France)

2001-11-15T23:59:59.000Z

316

Use of gamma-ray spectroscopy for direct detection of thermal neutrons  

Science Journals Connector (OSTI)

A neutron detector based on detection of the prompt gamma-radiation emitted as a result of neutron interaction with a suitable neutron absorber is described. Boron-10 loaded polyethylene is used as the neutron...

F. Ghanbari; A. H. Mohagheghi

2001-05-01T23:59:59.000Z

317

Neutron Generators Developed at LBNL for Homeland Security andImaging Applications  

SciTech Connect

The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0-9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration with a sub-surface material characterization on Mars. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Four main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-compact axial neutron generator for elemental analysis applications. Current status of the neutron generator development with experimental data will be presented.

Reijonen, Jani

2006-08-13T23:59:59.000Z

318

Neutron Radiography Facility in a Storage Pond of a Nuclear Power Station Equipped with Antimony-Beryllium Neutron Source  

Science Journals Connector (OSTI)

A neutron radiography facility is described, which has been ... . Some of the control elements contain the neutron absorbing material boron carbide, filled in tubes. Neutron radiography can be applied to detect a...

L. Greim; F. Borchers; M. Greim; G. W. Schumacher; H.-W. Schmitz…

1987-01-01T23:59:59.000Z

319

A High-Efficiency Neutron Detector  

Science Journals Connector (OSTI)

... for neutrons with energies lying between 100 and 100,000 eV. A practicable thickness of boron-10 (2-2J cm.) is effectively 'black' to neutrons of up to 10, ...

J. C. DUCKWORTH; A. W. MERRISON; A. WHITTAKER

1950-01-14T23:59:59.000Z

320

Muon Capture by Deuterons  

Science Journals Connector (OSTI)

Rates of muon capture from the separate ?d hyperfine states are computed. The dependence of the measurement of effective coupling constants on the neutron energy is explicitly demonstrated. The calculation of the neutron energy spectra includes mainly the following refinements: (1) use of two-nucleon wave functions with hard core, (2) corrections for the target-proton momentum, and (3) inclusion of certain induced pseudoscalar terms. The capture rates obtained are 334 and 15 sec-1 for the ?d doublet and quartet states, respectively.

I-T. Wang

1965-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Gamma-gamma directional correlation measurements in 130,132Xe following thermal neutron capture by natural xenon  

Science Journals Connector (OSTI)

Directional correlations of gamma-ray cascades in 130,132Xe have been measured following thermal n capture by a pressurised natural xenon gas target. Gamma-ray singles spectra were measured up to 5.5 MeV and the coincidence correlation data were obtained for the energy range 0.2-2.5 MeV. Decay schemes were developed on the basis of the coincidence measurements. The data spin-parity assignments to be made to most levels lying below 3.5 MeV in the 132Xe and the multiple mixing ratios to be evaluated for the more intense transitions. The results are fitted to IBM-1 and IBM-2 and are also compared with the prediction of the dynamic deformation model of Kumar (1983). The 23+ level at 1985 keV in 132Xe is considered to be a mixed-symmetry state with B(M1; 23+ to 21+)=0.29 mu N2.

S A Hamada; W D Hamilton; B More

1988-01-01T23:59:59.000Z

322

Cosmic Abundance of Boron  

Science Journals Connector (OSTI)

... of low energy cosmic rays might be the necessary mechanism to produce the additional boron.Boron-10 is produced by the reaction 13C(p,a)10B, which has a Q value ...

A. G. W. CAMERON; S. A. COLGATE; L. GROSSMAN

1973-05-25T23:59:59.000Z

323

Boron-10 ABUNCL Models of Fuel Testing  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report provides results from MCNP simulations of the General Electric Reuter-Stokes Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) active configuration model with fuel pins previously measured at Los Alamos National Laboratory. A comparison of the GE-ABUNCL simulations and simulations of 3He based UNCL-II active counter (the system for which the GE-ABUNCL was targeted to replace) with the same fuel pin assemblies is also provided.

Siciliano, Edward R.; Lintereur, Azaree T.; Kouzes, Richard T.; Ely, James H.

2013-10-01T23:59:59.000Z

324

Embrittlement of Stainless Steels and Nickel-Based Alloys at High Temperature Induced by Neutron Radiation  

Science Journals Connector (OSTI)

... not recovered15. Thus, the precipitation effects are not the prime cause of the embrittlement.Boron-10 appeared the most likely isotope because of its high thermal neutron cross-section. Rather ... metallurgical changes induced) a constant amount of boron was added in the form of either boron-10 or boron-11. Irradiation of these chemically and metallurgically similar steels clearly showed that ...

R. S. BARNES

1965-06-26T23:59:59.000Z

325

Combined TL and 10B-alanine ESR dosimetry for BNCT  

Science Journals Connector (OSTI)

......Mijnheer, B. J. Determination of dose components...neutron beam for boron neutron capture...Validation Studies | 0 Isotopes 7440-42-8 Boron | Body Burden...radiation effects Boron Neutron Capture...therapeutic use Humans Isotopes radiation effects......

A. Bartolotta; M. C. D'Oca; B. Lo Giudice; M. Brai; R. Borio; N. Forini; P. Salvadori; S. Manera

2004-08-01T23:59:59.000Z

326

Neutron detector  

DOE Patents (OSTI)

A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

Stephan, Andrew C. (Knoxville, TN); Jardret; Vincent D. (Powell, TN)

2011-04-05T23:59:59.000Z

327

Muon Capture by the Triton  

Science Journals Connector (OSTI)

Muon capture by the triton is investigated. "Exact" ground-state wave functions extracted from realistic nucleon-nucleon interactions are incorporated in the calculations. The treatment involves non-energy-weighted sum rules and explicit introduction of the three-neutron final state. Beside results on muon capture by He3, a lower limit is established for the muon-capture rate in H3.

J. Torre; Cl. Gignoux; G. Goulard

1978-02-20T23:59:59.000Z

328

Technologies for Boron Removal  

Science Journals Connector (OSTI)

Tests were performed to examine the removal of boron from aqueous solution either with polyvinyl alcohol (PVA) alone or by both PVA and other inorganic additives under room temperature. ... Added calcium hydroxide increased the co-removal of borate with PVA, and this offers a polishing treatment after borate removal by liming. ... As boron removal can be achieved by chemical precipitation and coagulation, it is logical to assume that the EC could remove boron from water and industrial effluent. ...

Yonglan Xu; Jia-Qian Jiang

2007-11-23T23:59:59.000Z

329

Designing an Epithermal Neutron Beam for Boron Neutron Capture Therapy for the Fusion Reactions 2H(d,n)3He and 3H(d,n)4He  

E-Print Network (OSTI)

of a Heterogeneous Phan- tom", MIRD Pamphlet No. 5 Revised,degrees with the axis of the MIRD 5 phantom backbone in the

Verbeke, J.M.; Costes, S.V.; Bleuel, D.; Vujic, J.; Leung, K.N.

1998-01-01T23:59:59.000Z

330

Microwave sintering of boron carbide  

DOE Patents (OSTI)

A method for forming boron carbide into a particular shape and densifying the green boron carbide shape. Boron carbide in powder form is pressed into a green shape and then sintered, using a microwave oven, to obtain a dense boron carbide body. Densities of greater than 95% of theoretical density have been obtained. 1 tab.

Blake, R.D.; Katz, J.D.; Petrovic, J.J.; Sheinberg, H.

1988-06-10T23:59:59.000Z

331

First neutron generation in the BINP accelerator based neutron source B. Bayanova  

E-Print Network (OSTI)

First neutron generation in the BINP accelerator based neutron source B. Bayanova , A. Burdakova c l e i n f o Keywords: Epithermal neutrons Lithium target Neutron capture therapy Tandem accelerator a b s t r a c t Pilot innovative facility for neutron capture therapy was built at Budker

Taskaev, Sergey Yur'evich

332

Neutron dose equivalent meter  

DOE Patents (OSTI)

A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

1996-01-01T23:59:59.000Z

333

Boron-10 ABUNCL Prototype Initial Testing  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report provides results of initial testing of an Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) design built by General Electric Reuter-Stokes. Several configurations of the ABUNCL models, which use 10B-lined proportional counters in place of 3He proportional counters for the neutron detection elements, were previously reported. The ABUNCL tested is of a different design than previously modeled. Initial experimental testing of the as-delivered passive ABUNCL was performed, and modeling will be conducted. Testing of the system reconfigured for active testing will be performed in the near future, followed by testing with nuclear fuel.

Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.

2012-12-01T23:59:59.000Z

334

Thermal Neutron Capture Therapy Using 10B1-Bpa: Inducement of Marked Lethal Effect on Melanoma Cells Irrespective of X-Ray Sensitivity  

Science Journals Connector (OSTI)

The G-361 cell line exposed to thermal neutron radiation after treatment with 10B1-BPA (100 ?g/ml medium), however, showed similar sensitivity to the P-39 cell line.

M. Ichihashi; H. Utsumi; H. Tsukamoto; Y. Mishima…

1993-01-01T23:59:59.000Z

335

Helical nanotubes of hexagonal boron nitride  

Science Journals Connector (OSTI)

......Physical: Full-length Papers Helical nanotubes of hexagonal boron nitride Masami Terauchi...Hongo, Bunkyo-ku, Tokyo 113, Japan Nanotubes of hexagonal boron nitride (h-BN...discovered. hexagonal boron nitride,|nanotube,|nanoball,|amorphous boron| C......

Masami Terauchi; Michiyoshi Tanaka; Hirofumi Matsuda; Masatoshi Takeda; Kaoru Kimura

1997-01-01T23:59:59.000Z

336

Neutron absorbing coating for nuclear criticality control  

DOE Patents (OSTI)

A neutron absorbing coating for use on a substrate, and which provides nuclear criticality control is described and which includes a nickel, chromium, molybdenum, and gadolinium alloy having less than about 5% boron, by weight.

Mizia, Ronald E. (Idaho Falls, ID); Wright, Richard N. (Idaho Falls, ID); Swank, William D. (Idaho Falls, ID); Lister, Tedd E. (Idaho Falls, ID); Pinhero, Patrick J. (Idaho Falls, ID)

2007-10-23T23:59:59.000Z

337

Comparison of CF4 and SF6 based plasmas for ECR etching of isotopically enriched 10Boron films  

SciTech Connect

Isotopically enriched {sup 10}boron films have been successfully etched in an ECR etching tool using CF{sub 4} and SF{sub 6} based plasmas. Comparisons between the two are made with regards to etch rate, selectivity to the underlying Si device structure, and morphology of the {sup 10}boron post-etching. The present film etching development is expected to be critical for the fabrication of next generation thermal neutron solid state detectors based on {sup 10}boron.

Voss, L F; Reinhardt, C E; Graff, R T; Conway, A M; Nikolic, R J; Deo, N; Cheung, C L

2009-02-23T23:59:59.000Z

338

Accelerator-based neutron brachytherapy  

Science Journals Connector (OSTI)

The development and evaluation of a new approach to neutronbrachytherapy is described. This approach accelerator-based fast neutronbrachytherapy involves the interstitial or intracavity insertion of a narrow evacuated accelerator beam tube such that its tip containing the neutron-producing target is placed in or near the tumor.Tumorirradiation via brachytherapy should result in a reduction in the healthy tissue complication rate observed when poorly collimated and/or low energy external neutron beam are used for treatment. Use of a variable energy accelerator provides an advantage over isotopesources for neutronbrachytherapy in that the neutron beam can be turned on and off and the neutronenergy spectrum varied for different treatment applications. A prototype accelerator-based fast neutronbrachytherapy device 10 cm long and 6 mm outer diameter has been constructed and evaluated in terms of its dosimetric output treatment time and practical feasibility. The prototype device is a tube-in-tube design with cooling water running between the inner and outer tubes to cool a beryllium target located at the tip of the inner tube. Cooling experiments were performed and coupled with Monte Carlo simulations to determine treatment times as a function of heat load for various neutron-producing reactions. Using the 9 Be (d n) 10 B reaction at E d =1.5 MeV 66 RBE-Gy (12 Gy physical dose) can be delivered to the boundary of a 4.5-cm-diam treatment volume in 8 min at a heat load of 130 W. Other reactions offer similar treatment times at somewhat higher bombarding energies and also show higher potential for dose enhancement with the boron-10 neutron capture reaction due to their softer neutron spectra. Dose distributions in a water phantom were measured with the prototype brachytherapy tube using the dual-ion chamber technique for the 9 Be (d n) 10 B reaction at E d =1.5 MeV. The measurements and simulations agree within uncertainties and demonstrate that fast neutrons contribute more than 90% of the dose to the target volume.

Haijun Song; Jacquelyn C. Yanch; Robert E. Klinkowstein

2002-01-01T23:59:59.000Z

339

Process for making boron nitride using sodium cyanide and boron  

DOE Patents (OSTI)

This a very simple process for making boron nitride by mixing sodium cyanide and boron phosphate and heating the mixture in an inert atmosphere until a reaction takes place. The product is a white powder of boron nitride that can be used in applications that require compounds that are stable at high temperatures and that exhibit high electrical resistance.

Bamberger, Carlos E. (Oak Ridge, TN)

1990-01-01T23:59:59.000Z

340

Boron nitride nanotubes as novel sorbent for solid-phase microextraction of polycyclic aromatic hydrocarbons in environmental water samples  

Science Journals Connector (OSTI)

Boron nitride nanotube (BNNT) is a novel material that shows potential ability in capturing organic pollutants. In this study, BNNTs fixed on a stainless steel fiber by a sol–gel technique were used as sorbent fo...

Meizhen Fu; Hanzhu Xing; Xiangfeng Chen…

2014-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

The Properties of Amorphous Boron  

Science Journals Connector (OSTI)

... few particles of amorphous boron are allowed to fall into fused potassium chlorate, quite a pyrotechnic display is produced. The behaviour of certain fluorides towards amorphous boron is interesting. Silver ...

A. E. TUTTON

1892-03-31T23:59:59.000Z

342

The System Boron—Oxygen  

Science Journals Connector (OSTI)

This presentation covers the years 1985 to 1988 and, in part, to 1992. It continues the previous discussion of the system boron—oxygen in “Boron Compounds” 3rd Suppl. Vol. 2, 1987, pp. 1/184, and earlier liter...

Gert Heller

1993-01-01T23:59:59.000Z

343

The System Boron-Nitrogen  

Science Journals Connector (OSTI)

This section, which is completed in “Boron Compounds” 4th Suppl. Vol. 3b (to be published), covers the period 1985 through 1988. It continues the treatment of “Boron Compounds” 3rd Suppl. Vol. 3, 1988, pp. 1/230.

Anton Meller

1991-01-01T23:59:59.000Z

344

Boron-10 ABUNCL Prototype Models And Initial Active Testing  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards and Security (NA-241) is supporting the project Coincidence Counting With Boron-Based Alternative Neutron Detection Technology at Pacific Northwest National Laboratory (PNNL) for the development of a 3He proportional counter alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a system based upon 10B-lined proportional tubes in a configuration typical for 3He-based coincidence counter applications. This report provides results from MCNPX model simulations and initial testing of the active mode variation of the Alternative Boron-Based Uranium Neutron Coincidence Collar (ABUNCL) design built by General Electric Reuter-Stokes. Initial experimental testing of the as-delivered passive ABUNCL was previously reported.

Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T.; Siciliano, Edward R.

2013-04-23T23:59:59.000Z

345

Design and Testing of a Boron Carbide Capsule for Spectral Tailoring in Mixed-Spectrum Reactors  

SciTech Connect

A boron carbide capsule has been designed and used for spectral-tailoring experiments at the TRIGA reactor at Washington State University. Irradiations were conducted in pulsed mode and in continuous operation for up to 4 hours. A cadmium cover was used to reduce thermal heating. The neutron spectrum calculated with MCNP was found to be in good agreement with reactor dosimetry measurements using the STAY'SL computer code. The neutron spectrum resembles that of a fast reactor. Design of a capsule using boron carbide enriched in {sup 10}B shows that it is possible to produce a neutron spectrum similar to {sup 235}U fission.

Greenwood, Lawrence R.; Wittman, Richard S.; Pierson, Bruce D.; Metz, Lori A.; Payne, Rosara F.; Finn, Erin C.; Friese, Judah I.

2012-03-01T23:59:59.000Z

346

It's Elemental - Isotopes of the Element Boron  

NLE Websites -- All DOE Office Websites (Extended Search)

Beryllium Beryllium Previous Element (Beryllium) The Periodic Table of Elements Next Element (Carbon) Carbon Isotopes of the Element Boron [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 10 19.9% STABLE 11 80.1% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 6 No Data Available Double Proton Emission (suspected) No Data Available 7 3.255×10-22 seconds Proton Emission No Data Available Alpha Decay No Data Available 8 770 milliseconds Electron Capture 100.00% Electron Capture with delayed Alpha Decay 100.00% 9 8.439×10-19 seconds Proton Emission 100.00% Double Alpha Decay 100.00%

347

Process for microwave sintering boron carbide  

DOE Patents (OSTI)

A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

Holcombe, C.E.; Morrow, M.S.

1993-10-12T23:59:59.000Z

348

Process for microwave sintering boron carbide  

DOE Patents (OSTI)

A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

Holcombe, Cressie E. (440 Sugarwood Dr., Knoxville, TN 37922); Morrow, Marvin S. (Rte. #3, Box 113, Kingston, TN 37763)

1993-01-01T23:59:59.000Z

349

Muon Capture in Heavy Nuclei  

Science Journals Connector (OSTI)

The systematics of muon capture rates in complex nuclei is discussed in the closure approximation. It is shown that for calculations in infinite nuclear matter, the nuclear ground state can be reasonably approximated by an infinite Fermi gas. The closure approximation and Fermi-gas model for the nuclear ground state are then used in an analysis of the experimental capture rates in a large number of nuclei. We find that this procedure does allow one to satisfactorily interpret quantitatively the muon-capture rates in the heavier nuclei and that it is possible to interpret the analysis in a manner which is not inconsistent with a universal Fermi interaction. The possibility of using muon capture rates to determine a neutron-proton nuclear-radius difference is also explored but with negative results.

R. Klein

1966-06-17T23:59:59.000Z

350

Characterization of a thermal neutron beam monitor based on gas electron multiplier technology  

Science Journals Connector (OSTI)

......from gadolinium isotopes (which adsorb neutrons...about 3980b and boron and thermal neutrons...Experimental details Boron carbide (B C...view allows the determination of the coating thickness...Simulation of different isotopes is obtained with...High-voltage scan and determination of working point......

Gabriele Croci; Carlo Cazzaniga; Gerardo Claps; Marco Tardocchi; Marica Rebai; Fabrizio Murtas; Espedito Vassallo; Roberto Caniello; Enrico Perelli Cippo; Giovanni Grosso; Valentino Rigato; Giuseppe Gorini

2014-08-01T23:59:59.000Z

351

Detection of Neutrons with Scintillation Counters  

DOE R&D Accomplishments (OSTI)

Detection of slow neutrons by: detection of single gamma rays following capture by cadmium or mercury; detection of more than one gamma ray by observing coincidences after capture; detection of heavy charged particles after capture in lithium or baron nuclei; possible use of anthracene for counting fast neutrons investigated briefly.

Hofstadter, R.

1948-11-01T23:59:59.000Z

352

Rhodium self-powered neutron detector as a suitable on-line thermal neutron flux monitor in BNCT treatments  

SciTech Connect

Purpose: A rhodium self-powered neutron detector (Rh SPND) has been specifically developed by the Comision Nacional de Energia Atomica (CNEA) of Argentina to measure locally and in real time thermal neutron fluxes in patients treated with boron neutron capture therapy (BNCT). In this work, the thermal and epithermal neutron response of the Rh SPND was evaluated by studying the detector response to two different reactor spectra. In addition, during clinical trials of the BNCT Project of the CNEA, on-line neutron flux measurements using the specially designed detector were assessed. Methods: The first calibration of the detector was done with the well-thermalized neutron spectrum of the CNEA RA-3 reactor thermal column. For this purpose, the reactor spectrum was approximated by a Maxwell-Boltzmann distribution in the thermal energy range. The second calibration was done at different positions along the central axis of a water-filled cylindrical phantom, placed in the mixed thermal-epithermal neutron beam of CNEA RA-6 reactor. In this latter case, the RA-6 neutron spectrum had been well characterized by both calculation and measurement, and it presented some marked differences with the ideal spectrum considered for SPND calibrations at RA-3. In addition, the RA-6 neutron spectrum varied with depth in the water phantom and thus the percentage of the epithermal contribution to the total neutron flux changed at each measurement location. Local (one point-position) and global (several points-positions) and thermal and mixed-field thermal neutron sensitivities were determined from these measurements. Thermal neutron flux was also measured during BNCT clinical trials within the irradiation fields incident on the patients. In order to achieve this, the detector was placed on patient's skin at dosimetric reference points for each one of the fields. System stability was adequate for this kind of measurement. Results: Local mixed-field thermal neutron sensitivities and global thermal and mixed-field thermal neutron sensitivities derived from measurements performed at the RA-6 were compared and no significant differences were found. Global RA-6-based thermal neutron sensitivity showed agreement with pure thermal neutron sensitivity measurements performed in the RA-3 spectrum. Additionally, the detector response proved nearly unchanged by differences in neutron spectra from real (RA-6 BNCT beam) and ideal (considered for calibration calculations at RA-3) neutron source descriptions. The results confirm that the special design of the Rh SPND can be considered as having a pure thermal response for neutron spectra with epithermal-to-thermal flux ratios up to 12%. In addition, the linear response of the detector to thermal flux allows the use of a mixed-field thermal neutron sensitivity of 1.95 {+-} 0.05 x 10{sup -21} A n{sup -1}{center_dot}cm{sup 2}{center_dot}s. This sensitivity can be used in spectra with up to 21% epithermal-to-thermal flux ratio without significant error due to epithermal neutron and gamma induced effects. The values of the measured fluxes in clinical applications had discrepancies with calculated results that were in the range of -25% to +30%, which shows the importance of a local on-line independent measurement as part of a treatment planning quality control system. Conclusions: The usefulness of the CNEA Rh SPND for the on-line local measurement of thermal neutron flux on BNCT patients has been demonstrated based on an appropriate neutron spectra calibration and clinical applications.

Miller, Marcelo E.; Sztejnberg, Manuel L.; Gonzalez, Sara J.; Thorp, Silvia I.; Longhino, Juan M.; Estryk, Guillermo [Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429 (Argentina); Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429, Argentina and CONICET, Av. Rivadavia 1917, Ciudad de Buenos Aires 1033 (Argentina); Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429 (Argentina)

2011-12-15T23:59:59.000Z

353

New analysis of the two carbon-rich stars CS 22948-27 and CS 29497-34 : binarity and neutron-capture elements  

E-Print Network (OSTI)

We have carried out a new determination of abundances in the very metal-poor CH/CN strong stars CS 29497-34 and CS 22948-27, using high-resolution spectra obtained with the HARPS spectrograph at the 3.6m telescope of ESO, La Silla, that covers the range 400 - 690 nm at a resolution of R = 100,000. Both stars are found to be long period binaries. It is confirmed that the abundance patterns show an enhancement of all the alpha-elements (like Mg, Ca), of the proton capture elements (like Na and Al) and a strong enrichment in "r" and "s" process elements, where the s-enrichment is probably due to a mass transfer episode from a companion in its AGB phase. The possible origins of the abundance pattern and especially of the strong enhancement of both "s" and "r" elements are discussed.

B. Barbuy; M. Spite; F. Spite; V. Hill; R. Cayrel; B. Plez; P. Petitjean

2004-09-09T23:59:59.000Z

354

Radiative neutron capture by {sup 2}H, {sup 7}Li, {sup 14}C, and {sup 14}N nuclei at astrophysical energies  

SciTech Connect

The possibility of describing experimental data on the total cross sections for the n{sup 2}H, n{sup 7}Li, n{sup 14}C, and n{sup 14}N radiative-capture processes within the potential cluster model involving forbidden states and their classification according to Young's tableaux is considered. It is shown that this model and the methods used here to construct potentials make it possible to describe correctly the behavior of the experimental cross sections at energies between 5 to 10 meV (5 Multiplication-Sign 10{sup -3}-10 Multiplication-Sign 10{sup -3} eV) and 1 to 15MeV.

Dubovichenko, S. B., E-mail: dubovichenko@mail.ru [V.G. Fessenkov Astrophysical Institute NCSRT NSA RK (Kazakhstan)

2013-07-15T23:59:59.000Z

355

Application of different TL detectors for the photon dosimetry in mixed radiation fields used for BNCT  

Science Journals Connector (OSTI)

......neutrons as used for Boron Neutron Capture...The experimental determination of the thermal neutron...INTRODUCTION In BNCT a boron compound enriched...and 7LiF of such isotope compositions are...neutrons as used for Boron Neutron Capture...The experimental determination of the thermal neutron......

B. Burgkhardt; P. Bilski; M. Budzanowski; R. Böttger; K. Eberhardt; G. Hampel; P. Olko; A. Straubing

2006-09-01T23:59:59.000Z

356

neutron density. The neutron density (nn) of the source was modeled by solving the simul-  

E-Print Network (OSTI)

neutron density. The neutron density (nn) of the source was modeled by solving the simul- taneousT is the thermal neutron velocity, l is the decay constant, Ns is the s-process abun- dance, bs� is the maxwellian-averaged neutron capture cross-section, and t0 is the average neutron exposure (21). The branching decay of 186Re

West, Stuart

357

A neutron producing target for BINP accelerator-based neutron source B. Bayanova  

E-Print Network (OSTI)

A neutron producing target for BINP accelerator-based neutron source B. Bayanova , E. Kashaeva b l e i n f o Keywords: Target Lithium Neutron capture therapy Epithermal neutrons a b s t r a c t An innovative accelerator-based neutron source for BNCT has just started operation at the Budker Institute

Taskaev, Sergey Yur'evich

358

The polarographic microdetermination of boron  

E-Print Network (OSTI)

? ment, has been demonstrated by the ferrous metals industry. Minute amounts of boron have been employed to increase the hardenability of steel. For instance, 0.003 % boron may be substituted for 0.3 % chromium, 0.2 % manganese, 0.12 % vanadium or 0...? ment, has been demonstrated by the ferrous metals industry. Minute amounts of boron have been employed to increase the hardenability of steel. For instance, 0.003 % boron may be substituted for 0.3 % chromium, 0.2 % manganese, 0.12 % vanadium or 0...

Peacock, Dixon Williams

2013-10-04T23:59:59.000Z

359

Dose Sparing of Capillary Endothelial Cells for BSH and BPA  

Science Journals Connector (OSTI)

In Boron Neutron Capture Therapy (BNCT), boron is selectively taken up by cancer cells and activated in situ by a beam of neutrons. However, boron is also taken up by normal cells in some fixed relationship wi...

D. E. Charlton; B. J. Allen

1996-01-01T23:59:59.000Z

360

Distribution of BPA and metabolic assessment in glioblastoma patients during BNCT treatment: a microdialysis study  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is dependent on the selective accumulation of boron-10 in tumour cells. To maximise the radiation effect, the neutrons should be delivered when the ratio between the boron ...

A. Tommy Bergenheim; Jacek Capala; Michael Roslin…

2005-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Radionuclide neutron sources in calibration laboratory—neutron and gamma doses and their changes in time  

Science Journals Connector (OSTI)

......radiation require the determination of this component...been applied for the determination of neutron ambient...equivalent rate and for the determination of neutron and gamma...nominal decay of the main isotope. After 15-20 y...blocks, enclosing the boron or helium proportional......

K. Józefowicz; N. Golnik; P. Tulik; M. Zielczynski

2007-08-01T23:59:59.000Z

362

Boron containing multilayer coatings and method of fabrication  

DOE Patents (OSTI)

Hard coatings are fabricated from multilayer boron/boron carbide, boron carbide/cubic boron nitride, and boron/boron nitride/boron carbide, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron and boron carbide used in forming the multilayers are formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/boron carbide, and boron carbide/cubic boron nitride is produced by depositing alternate layers of boron, cubic boron nitride or boron carbide, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be of a discrete or a blended or graded composition.

Makowiecki, Daniel M. (Livermore, CA); Jankowski, Alan F. (Livermore, CA)

1997-01-01T23:59:59.000Z

363

It's Elemental - The Element Boron  

NLE Websites -- All DOE Office Websites (Extended Search)

Beryllium Beryllium Previous Element (Beryllium) The Periodic Table of Elements Next Element (Carbon) Carbon The Element Boron [Click for Isotope Data] 5 B Boron 10.811 Atomic Number: 5 Atomic Weight: 10.811 Melting Point: 2348 K (2075°C or 3767°F) Boiling Point: 4273 K (4000°C or 7232°F) Density: 2.37 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Semi-metal Period Number: 2 Group Number: 13 Group Name: none What's in a name? From the Arabic word Buraq and the Persian word Burah, which are both words for the material "borax." Say what? Boron is pronounced as BO-ron. History and Uses: Boron was discovered by Joseph-Louis Gay-Lussac and Louis-Jaques Thénard, French chemists, and independently by Sir Humphry Davy, an English chemist,

364

Functionalized boron nitride nanotubes  

DOE Patents (OSTI)

A plasma treatment has been used to modify the surface of BNNTs. In one example, the surface of the BNNT has been modified using ammonia plasma to include amine functional groups. Amine functionalization allows BNNTs to be soluble in chloroform, which had not been possible previously. Further functionalization of amine-functionalized BNNTs with thiol-terminated organic molecules has also been demonstrated. Gold nanoparticles have been self-assembled at the surface of both amine- and thiol-functionalized boron nitride Nanotubes (BNNTs) in solution. This approach constitutes a basis for the preparation of highly functionalized BNNTs and for their utilization as nanoscale templates for assembly and integration with other nanoscale materials.

Sainsbury, Toby; Ikuno, Takashi; Zettl, Alexander K

2014-04-22T23:59:59.000Z

365

Dry etching techniques for active devices based on hexagonal boron nitride epilayers  

SciTech Connect

Hexagonal boron nitride (hBN) has emerged as a fundamentally and technologically important material system owing to its unique physical properties including layered structure, wide energy bandgap, large optical absorption, and neutron capture cross section. As for any materials under development, it is necessary to establish device processing techniques to realize active devices based on hBN. The authors report on the advancements in dry etching techniques for active devices based on hBN epilayers via inductively coupled plasma (ICP). The effect of ICP radio frequency (RF) power on the etch rate and vertical side wall profile was studied. The etching depth and angle with respect to the surface were measured using atomic force microscopy showing that an etching rate ?1.25 ?m/min and etching angles >80° were obtained. Profilometer data and scanning electron microscope images confirmed these results. This work demonstrates that SF{sub 6} is very suitable for etching hBN epilayers in RF plasma environments and can serve as a guide for future hBN device processing.

Grenadier, Samuel; Li, Jing; Lin, Jingyu; Jiang, Hongxing [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)] [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)

2013-11-15T23:59:59.000Z

366

Neutron detection properties of Li6Y(BO3)3:Ce crystal  

Science Journals Connector (OSTI)

Abstract Li6Y(BO3)3:Ce crystal is a promising type of scintillator for neutron detection. In this study, the properties of Li6Y(BO3)3:3at%Ce are studied, including its ? sensitivity, neutron efficiency, ?/? ratio, relative light yield, neutron pulse-height spectrum and decay time. Geant4 simulations indicate that its capture efficiency for thermal neutrons is as high as 78% for the natural abundances of the boron and lithium elements. The ?/? ratio of Li6Y(BO3)3:Ce is measured to be 0.03, which is 10 times lower than that of lithium glass. If the per-MeV light yield of lithium glass is defined to be 100, then the light yields generated by Li6Y(BO3)3:Ce for ? rays and ? particles are 253.3 and 24.8, respectively. Under ?-ray irradiation, the light yield of Li6Y(BO3)3:Ce is approximately 6 times lower than that of NaI:Tl. In neutron detection, the neutron signal can be clearly distinguished from the backgrounds caused by the 252Cf source itself. Li6Y(BO3)3:Ce is also a fast scintillator, with decay times of 48.6 ± 14.4 ns, 24.6 ± 13.3 ns and 37.8 ± 17.8 ns under irradiation with ? rays, ? particles and thermal neutrons, respectively. This study offers a systematic study of useful parameters of Li6Y(BO3)3:3at%Ce crystal for application in and the improvement of neutron detection.

Zaiwei Fu; Shangke Pan; Fan Yang; Shenjie Gu; Xiangcui Lei; Yuekun Heng; Guohao Ren; Ming Qi

2015-01-01T23:59:59.000Z

367

European Developments in Radiotherapy with Beams of Large Radiobiological Effectiveness  

Science Journals Connector (OSTI)

......FRM II in Munich.4) Boron Neutron Capture Therapy...the positron emitting isotopes by a PET camera during...for the on-line PET determination of the dose distribution...patients treated with boron neutron capture therapy......

Ugo Amaldi; Gerhard Kraft

2007-03-01T23:59:59.000Z

368

E-Print Network 3.0 - astrophysical rapid proton-capture Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron and proton capture reactions... explosions 3, as well ass type I X-ray bursts (rapid proton capture process, rp-process) 4, and might... iron 2. Meanwhile...

369

Sub-barrier capture reactions with $^{16,18}$O beams  

E-Print Network (OSTI)

Various sub-barrier capture reactions with beams $^{16,18}$O are treated within the quantum diffusion approach. The role of neutron transfer in these capture reactions is discussed.

V. V. Sargsyan; G. G. Adamian; N. V. Antonenko; W. Scheid; H. Q. Zhang

2012-11-19T23:59:59.000Z

370

Characterization of electrodeposited elemental boron  

SciTech Connect

Elemental boron was produced through electrowinning from potassium fluoroborate dissolved in a mixture of molten potassium fluoride and potassium chloride. The characteristics of the electrodeposited boron (raw boron) as well as the water and acid-leached product (processed boron) were studied. The chemical purity, specific surface area, size distribution of particles and X-ray crystallite size of the boron powders were investigated. The morphology of the deposits was examined using scanning electron microscopy (SEM). The chemical state of the matrix, as well as the impurity phases present in them, was established using X-ray photoelectron spectroscopy (XPS). In order to interpret and understand the results obtained, a thermodynamic analysis was carried out. The gas-phase corrosion in the head space as well as the chemistry behind the leaching process were interpreted using this analysis. The ease of oxidation of these powders in air was investigated using differential thermal analysis (DTA) coupled with thermogravimetry (TG). From the results obtained in this study it was established that elemental boron powder with a purity of 95-99% could be produced using a high temperature molten salt electrowinning process. The major impurities were found to be oxygen, carbon, iron and nickel.

Jain, Ashish [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102 (India); Anthonysamy, S. [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102 (India)], E-mail: sas@igcar.gov.in; Ananthasivan, K.; Ranganathan, R. [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102 (India); Mittal, Vinit; Narasimhan, S.V. [Water and Steam Chemistry Division, BARC (F), Kalpakkam, 603102 (India); Vasudeva Rao, P.R. [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102 (India)

2008-07-15T23:59:59.000Z

371

Dose imaging with gel-dosemeter layers: optical analysis and dedicated software  

Science Journals Connector (OSTI)

......Fricke-gel dosimetry in boron neutron capture therapy...all dose components in boron neutron capture therapy...Three-dimensional determination of absorbed dose by spectrophotometric...gel matrix of suitable isotopes does not sensibly alter...improving its suitability to boron neutron capture therapy......

G. Gambarini; M. Carrara; S. Gay; S. Tomatis

2006-09-01T23:59:59.000Z

372

Capturing carbon | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Capturing carbon Capturing carbon New technology enables molecular-level insight into carbon sequestration Carbon sequestration is a potential solution for reducing greenhouse...

373

Light radioactive nuclei capture reactions with phenomenological potential models  

E-Print Network (OSTI)

Light radioactive nuclei play an important role in many astrophysical environments. Due to very low cross sections of some neutron and proton capture reactions by these radioactive nuclei at energies of astrophysical interest, direct laboratory measurements are very difficult. For radioactive nuclei such as 8Li and 8B, the direct measurement of neutron capture reactions is impossible. Indirect methods have been applied to overcome these difficulties. In this work we will report on the results and discussion of phenomenological potential models used to determine some proton and neutron capture reactions. As a test we show the results for the 16O(p,g)17F_gs(5/2+) and 16O(p,g)17F_ex(1/2+) capture reactions.We also computed the nucleosynthesis cross sections for the 7Li(n,g)8Li, 8Li(n,g)9Li and 8B(p,g)9C capture reactions.

V. Guimaraes; C. A. Bertulani

2009-12-01T23:59:59.000Z

374

280 TECIINICAL NOTES Statistical Estimates of Thermal Neutron  

E-Print Network (OSTI)

280 TECIINICAL NOTES Statistical Estimates of Thermal Neutron Capture Cross Sections Yu. V. PetrovDecember9, I983 AcceptedJune 13, 1984 Abstract-Fluctuations of neutron resonance param- eters result in the observed distribution of the thermal neutron capture crosssections. The statistical approach allowing

Shlyakhter, Ilya

375

280 TECHNICAL NOTES Statistical Estimates of Thermal Neutron  

E-Print Network (OSTI)

280 TECHNICAL NOTES Statistical Estimates of Thermal Neutron Capture Cross Sections Yu. V. Petrov December 9, 1983 Accepted June 13, 1984 Abstract-Fluctuations of neutron resonance param- eters result in the observed distribution of the thermal neutron capture cross sections. Thestatistical approach allowingfor

Shlyakhter, Ilya

376

Muon Capture in Gaseous Hydrogen  

Science Journals Connector (OSTI)

An experiment to measure the muon nuclear capture rate in ultrapure gaseous hydrogen (8 atm, 293°K) has been performed using a special target in which a system of gas proportional counters, working with the pure hydrogen of the target itself, were operating. Neutrons from the capture reactions were detected using a scintillation-counter technique, and the ?-ray background was eliminated by pulse-shape discrimination. The working conditions ensured that the captures were taking place in ?p atomic systems in a singlet total-spin state. The experimental result is ?expt=651±57 sec-1, which has to be compared with the theoretical rate ?s, theor=626±26 sec-1. From the experimental capture rate, and within the framework of the currently accepted theory, we have obtained for the induced pseudoscalar coupling constant gp=(-7.3±3.7)gV. The results of the present experiment are analyzed, together with results obtained from stopping negative muons in liquid hydrogen.

A. Alberigi Quaranta; A. Bertin; G. Matone; F. Palmonari; G. Torelli; P. Dalpiaz; A. Placci; E. Zavattini

1969-01-25T23:59:59.000Z

377

Disintegration of Boron-10 by Protons  

Science Journals Connector (OSTI)

... -particles from the disintegration of boron-11 were eliminated by using a target of separated boron-10. The accompanying graph shows the number of particles counted as a function of current ... (1) at 630 keV. proton energy, and

W. E. BURCHAM; JOAN M. FREEMAN

1949-01-29T23:59:59.000Z

378

Boron Nitride Porous Microbelts for Hydrogen Storage  

Science Journals Connector (OSTI)

Boron Nitride Porous Microbelts for Hydrogen Storage ... However, the attention paid to their potential applications in gas sorption, especially in case of hydrogen, has obviously been insufficient. ... boron nitride; porous; microbelts; specific surface area; hydrogen storage ...

Qunhong Weng; Xuebin Wang; Chunyi Zhi; Yoshio Bando; Dmitri Golberg

2013-01-09T23:59:59.000Z

379

First neutron generation in the BINP accelerator based neutron source  

Science Journals Connector (OSTI)

Pilot innovative facility for neutron capture therapy was built at Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10 mA. Epithermal neutrons are proposed to be generated by 1.915 MeV protons bombarding a lithium target using 7Li(p,n)7Be threshold reaction. The results of the first experiments on neutron generation are reported and discussed.

B. Bayanov; A. Burdakov; V. Chudaev; A. Ivanov; S. Konstantinov; A. Kuznetsov; A. Makarov; G. Malyshkin; K. Mekler; I. Sorokin; Yu. Sulyaev; S. Taskaev

2009-01-01T23:59:59.000Z

380

Neutron production by cosmic-ray muons at shallow depth J. Busenitz,1  

E-Print Network (OSTI)

Neutron production by cosmic-ray muons at shallow depth F. Boehm,3 J. Busenitz,1 B. Cook,3 G Received 23 June 2000; published 12 October 2000 The yield of neutrons produced by cosmic ray muons of one and two neutron captures was determined. Modeling the neutron capture efficiency allowed us

Piepke, Andreas G.

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Boron doping a semiconductor particle  

DOE Patents (OSTI)

A method (10,30) of boron doping a semiconductor particle using boric acid to obtain a p-type doped particle. Either silicon spheres or silicon powder is mixed with a diluted solution of boric acid having a predetermined concentration. The spheres are dried (16), with the boron film then being driven (18) into the sphere. A melt procedure mixes the driven boron uniformly throughout the sphere. In the case of silicon powder, the powder is metered out (38) into piles and melted/fused (40) with an optical furnace. Both processes obtain a p-type doped silicon sphere with desired resistivity. Boric acid is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirements.

Stevens, Gary Don (18912 Ravenglen Ct., Dallas, TX 75287); Reynolds, Jeffrey Scott (703 Horizon, Murphy, TX 75094); Brown, Louanne Kay (2530 Poplar Tr., Garland, TX 75042)

1998-06-09T23:59:59.000Z

382

Neutron scattering in concrete and wood: Part II—oblique incidence  

Science Journals Connector (OSTI)

......Scientific and Technical Notes Neutron scattering in concrete and wood: Part...radiotherapy rooms. (b) Geometry of neutron scattering simulations. Another empirical...due to capture gamma rays. NEUTRON SCATTERING-MONTE CARLO SIMULATION RESULTS......

A. Facure; A. X. Silva; J. C. Rivera; R. C. Falcão

2008-02-01T23:59:59.000Z

383

SOURCES: a code for calculating (,n), spontaneous fission, and delayed neutron sources and spectra  

Science Journals Connector (OSTI)

......available nuclides are isotopes of Po, Rn, Ra, Th...as well as six Pu isotopes and one Be isotope were present. Reasonable...including lithium, 9Be, boron, carbon, oxygen...23. Stewart, L. Determination of the neutron spectrum......

W. B. Wilson; R. T. Perry; W. S. Charlton; T. A. Parish; E. F. Shores

2005-12-20T23:59:59.000Z

384

Development of 10B2O3 processing for use as a neutron conversion material  

Science Journals Connector (OSTI)

Development of thermal neutron detectors is critical for a number of homeland security and physics applications. In this work, we describe our efforts towards developing boron-10 oxide (10B2O3) as a thermal neutr...

L. F. Voss; J. Oiler; A. M. Conway…

2012-01-01T23:59:59.000Z

385

A Potential New BNCT Agent  

Science Journals Connector (OSTI)

Boron neutron capture therapy (BNCT) is a binary approach to cancer therapy.1 In this protocol, boron-10 is delivered to the tumor tissue, and ... the selective delivery of a sufficient quantity of boron-10 to th...

G. W. Kabalka; G. Li; R. R. Srivastava

2001-01-01T23:59:59.000Z

386

Muon Capture in Gaseous Deuterium  

Science Journals Connector (OSTI)

We report the results of an experiment performed to measure the muon nuclear capture rate by free deuterons. The muons were slowed down in ultrapure gaseous hydrogen at 7.6 atm and 293 °K, containing 5% of deuterium. A special target was used, in which a system of gas proportional counters, working with the (H2 + D2) gaseous mixture itself, was operating. Neutrons from the capture reactions were detected using liquid scintillation counters, and the ?-ray background was eliminated by pulse-shape discrimination. The experimental result is ?exp=(445±60) sec-1, which is consistent with muon-electron universality and with the assumption that the nuclear capture proceeds from the doublet spin state of the ?d muonic atoms. Combining the present experimental value with a previous result obtained with a liquid-hydrogen deuterated target, one obtains a ratio between the axial-vector and vector coupling constants given by gA,?gV,?=-1.35±0.1.

A. Bertin; A. Vitale; A. Placci; E. Zavattini

1973-12-01T23:59:59.000Z

387

Carbon Capture and Storage  

Science Journals Connector (OSTI)

The main object of the carbon capture and storage (CCS) technologies is the...2...emissions produced in the combustion of fossil fuels such as coal, oil, or natural gas. CCS involves first the capture of the emit...

Ricardo Guerrero-Lemus; José Manuel Martínez-Duart

2013-01-01T23:59:59.000Z

388

Design and development of a 3He replacement safeguards neutron counter based on 10B-lined proportional detector technology  

SciTech Connect

This presentation represents an overview of the experimental evaluation of a boron-lined proportional technology performed within an NA-241 sponsored project on testing of boron-lined proportional counters for the purpose of replacement of {sup 3}He technologies. The presented boron-lined technology will be utilized in a design of a full scale safeguards neutron coincidence counter. The design considerations and the Monte Carlo performance predictions for the counter are also presented.

Henzlova, Daniela [Los Alamos National Laboratory; Evans, Louise [Los Alamos National Laboratory; Menlove, Howard O. [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Rael, Carlos D. [Los Alamos National Laboratory; Martinez, Isaac P. [Los Alamos National Laboratory; Marlow, Johnna B. [Los Alamos National Laboratory

2012-07-16T23:59:59.000Z

389

EVOLUTION OF PROGENITORS FOR ELECTRON CAPTURE SUPERNOVAE  

SciTech Connect

We provide progenitor models for electron capture supernovae (ECSNe) with detailed evolutionary calculation. We include minor electron capture nuclei using a large nuclear reaction network with updated reaction rates. For electron capture, the Coulomb correction of rates is treated and the contribution from neutron-rich isotopes is taken into account in each nuclear statistical equilibrium (NSE) composition. We calculate the evolution of the most massive super asymptotic giant branch stars and show that these stars undergo off-center carbon burning and form ONe cores at the center. These cores become heavier up to the critical mass of 1.367 M{sub Sun} and keep contracting even after the initiation of O+Ne deflagration. Inclusion of minor electron capture nuclei causes convective URCA cooling during the contraction phase, but the effect on the progenitor evolution is small. On the other hand, electron capture by neutron-rich isotopes in the NSE region has a more significant effect. We discuss the uniqueness of the critical core mass for ECSNe and the effect of wind mass loss on the plausibility of our models for ECSN progenitors.

Takahashi, Koh; Umeda, Hideyuki [Department of Astronomy, University of Tokyo, Tokyo 113-0033 (Japan); Yoshida, Takashi, E-mail: ktakahashi@astron.s.u-tokyo.ac.jp, E-mail: umeda@astron.s.u-tokyo.ac.jp, E-mail: yoshida@yukawa.kyoto-u.ac.jp [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

2013-07-01T23:59:59.000Z

390

Alternative Neutron Detection Testing Summary  

SciTech Connect

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. Most currently deployed radiation portal monitors (RPMs) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large area neutron detector. This type of neutron detector is used in the TSA and other RPMs installed in international locations and in the Ludlum and Science Applications International Corporation RPMs deployed primarily for domestic applications. There is a declining supply of 3He in the world and, thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. These technologies are: 1) Boron trifluoride-filled proportional counters, 2) Boron-lined proportional counters, 3) Lithium-loaded glass fibers, and 4) Coated wavelength-shifting plastic fibers. Reported here is a summary of the testing carried out at Pacific Northwest National Laboratory on these technologies to date, as well as measurements on 3He tubes at various pressures. Details on these measurements are available in the referenced reports. Sponsors of these tests include the Department of Energy (DOE), Department of Homeland Security (DHS), and the Department of Defense (DoD), as well as internal Pacific Northwest National Laboratory funds.

Kouzes, Richard T.; Ely, James H.; Erikson, Luke E.; Kernan, Warnick J.; Lintereur, Azaree T.; Siciliano, Edward R.; Stromswold, David C.; Woodring, Mitchell L.

2010-04-08T23:59:59.000Z

391

Sub-barrier capture reactions with $^{16,18}$O and $^{40,48}$Ca beams  

E-Print Network (OSTI)

Various sub-barrier capture reactions with beams $^{16,18}$O and $^{40,48}$Ca are treated within the quantum diffusion approach. The role of neutron transfer in these capture reactions is discussed. The quasielastic and capture barrier distributions are analyzed and compared with the recent experimental data.

V. V. Sargsyan; G. G. Adamian; N. V. Antonenko; W. Scheid; H. Q. Zhang

2013-04-22T23:59:59.000Z

392

Structure and transformation of the metastable boron- and oxygen-related defect center in crystalline silicon  

Science Journals Connector (OSTI)

We analyze the core structure of the carrier-lifetime-reducing boron- and oxygen-related metastable defect center in crystalline silicon by measuring the correlation of the defect concentration with the boron and the oxygen contents on a large number of different silicon materials. The experimental results indicate that the defect is composed of one substitutional boron and two interstitial oxygen atoms. Formation and annihilation of the metastable boron-oxygen complex are found to be thermally activated processes, characterized by two strongly differing activation energies. Measurements of the defect generation rate as a function of light intensity show that the defect generation rate increases proportionally with light intensity below 1 mW/cm2 and saturates at higher intensities. All experimental results can be consistently explained using a defect reaction model based on fast-diffusing oxygen dimers (O2i), which are captured by substitutional boron (Bs) to form a metastable Bs-O2i complex. Based on this model, new strategies for an effective reduction of the light degradation of solar cells made on oxygen-rich silicon materials are derived. The model also explains why no lifetime degradation is observed in aluminum-, gallium-, and indium-doped oxygen-rich silicon.

Jan Schmidt and Karsten Bothe

2004-01-22T23:59:59.000Z

393

Neutron reflectometry  

Science Journals Connector (OSTI)

Neutron reflectivity is a powerful tool for the ... chapter include: the theory of elastic specular neutron diffraction; polarized neutron reflectivity; surface roughness; experimental methodology; resolution in ...

G. S. Smith; C. F. Majkrzak

2004-01-01T23:59:59.000Z

394

PALM - Laser Capture Microdissection | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

PALM - Laser Capture Microdissection PALM - Laser Capture Microdissection This Laser Capture Microdissection system is equipped with 100 x objective lens for enriching distinct...

395

NETL: Carbon Capture FAQs  

NLE Websites -- All DOE Office Websites (Extended Search)

How is CO2 captured? How is CO2 captured? Chilled Ammonia CO2 Capture Process Facility at American Electric Power's (AEP) Mountaineer Plant Chilled Ammonia CO2 Capture Process Facility at American Electric Power's (AEP) Mountaineer Plant Carbon dioxide (CO2) capture involves separating CO2 from other gases generated by industrial processes or burning fossil fuels. CO2 capture can remove as much as 95% of the CO2 from these processes. There are two major types of anthropogenic CO2 sources: mobile and stationary. Mobile sources include things like cars, trucks, trains, boats, and aircrafts that burn fossil fuels and generate CO2. Capturing CO2 from mobile sources is currently impractical. Stationary sources include power plants and industrial facilities that burn fossil fuels, as

396

Cryogenic Carbon Capture  

SciTech Connect

IMPACCT Project: SES is developing a process to capture CO2 from the exhaust gas of coal-fired power plants by desublimation - the conversion of a gas to a solid. Capturing CO2 as a solid and delivering it as a liquid avoids the large energy cost of CO2 gas compression. SES’ capture technology facilitates the prudent use of available energy resources. Coal is our most abundant energy resource and is an excellent fuel for baseline power production. SES capture technology can capture 99% of the CO2 emissions in addition to a wide range of other pollutants more efficiently and at lower costs than existing capture technologies. SES’ capture technology can be readily added to our existing energy infrastructure.

None

2010-07-15T23:59:59.000Z

397

Neutron-Neutron Interaction  

Science Journals Connector (OSTI)

The present status of the problem of charge dependence is discussed. The information about the neutron-neutron interaction derived from the two-neutron system, three-nucleon systems, final-state interactions in multiparticle reactions, and peripheral processes is critically evaluated. The experimental data indicate the breakdown of charge independence by about 3-5%. Evidence concerning the violation of charge symmetry is inconclusive, but it seems that most of the data are consistent with the assumption that charge symmetry is satisfied within 0.5-1%. The most suitable studies which might improve the knowledge of the neutron-neutron forces are indicated.

IVO ŠLAUS

1967-07-01T23:59:59.000Z

398

-ray Irradiation Enhanced Boron-10 Compound Accumulation in Murine Tumors  

Science Journals Connector (OSTI)

......gamma-ray Irradiation Enhanced Boron-10 Compound Accumulation in Murine Tumors...effects of gamma-ray irradiation on boron-10 compound accumulation in a murine...sodium) administration. Then, the boron-10 concentrations in tumor and normal......

Yong Liu; Kenji Nagata; Shin-ichiro Masunaga; Minoru Suzuki; Genro Kashino; Yuko Kinashi; Hiroki Tanaka; Yoshinori Sakurai; Akira Maruhashi; Koji Ono

2009-11-01T23:59:59.000Z

399

Alternative materials to cadmium for neutron absorbers in safeguards applications  

SciTech Connect

Cadmium is increasingly difficult to use in safeguards applications because of rising cost and increased safety regulations. This work examines the properties of two materials produced by Ceradyne, inc. that present alternatives to cadmium for neutron shielding. The first is an aluminum metal doped with boron and the second is a boron carbide powder, compressed into a ceramic. Both are enriched in the {sup 10}B isotope. Two sheets of boron doped aluminum (1.1 mm and 5.2mm thick) and one sheet of boron carbide (8.5mm thick) were provided by Ceradyne for testing. An experiment was designed to test the neutron absorption capabilities of these three sheets against two different thicknesses of cadmium (0.6mm and 1.6mm thick). The thinner piece of aluminum boron alloy (1.1mm) performed as well as the cadmium pieces at absorbing neutrons. The thicker aluminum-boron plate provided more shielding than the cadmium sheets and the boron carbide performed best by a relatively large margin. Monte Carlo N-Particle eXtended (MCNPX) transport code modeling of the experiment was performed to provide validaLed computational tools for predicting the behavior of systems in which these materials may be incorporated as alternatives to cadmium. MCNPX calculations predict that approximately 0.17mm of the boron carbide is equivalent to 0.6mm of cadmium. There are drawbacks to these materials that need to be noted when considering using them as replacements for cadmium. Notably, they may need to be thicker than cadmium, and are not malleable, requiring machining to fit any curved forms.

Freeman, Corey R [Los Alamos National Laboratory; Geist, William H [Los Alamos National Laboratory; West, James D [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

400

Method for making boron carbide cermets  

DOE Patents (OSTI)

A method for synthesizing low density cermets of boron carbide and a metal binder, using decomposition of a metallic compound at controlled temperature and pressure is disclosed.

Cline, C.F.; Fulton, F.J.

1987-11-03T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Method for making boron carbide cermets  

DOE Patents (OSTI)

A method for synthesizing low density cermets of boron carbide and a metal binder, using decomposition of a metallic compound at controlled temperature and pressure.

Cline, Carl F. (Danville, CA); Fulton, Fred J. (Livermore, CA)

1987-01-01T23:59:59.000Z

402

Boron mullite: Formation and basic characterization  

SciTech Connect

Graphical abstract: Display Omitted Highlights: ? Decrease of B-mullite formation temperature with increasing boron content. ? Decrease of lattice parameters b and c with increasing boron content. ? Significant reduction of thermal expansion (?15%) due to incorporation of boron. ? Decomposition of B-mullite at 1400 °C, long-term stability at 800 °C. -- Abstract: A series of boron doped mullites (B-mullite) was prepared from single-phase gels with initial compositions based on a 1:1 isomorphous substitution of Si by B, starting from a 3:2 mullite composition (Al{sub 4.5}Si{sub 1.5}O{sub 9.75}). A high amount of boron (>10 mol.%) can be incorporated into the crystal structure of mullite where it most likely replaces Si. In situ phase formation of B-mullites was studied with high temperature X-ray diffraction and thermal analysis. A decrease of the formation temperature for B-mullite with increasing boron content was observed. With increasing boron content lattice parameters b and c significantly decrease, while no systematic evolution of a is observed. Long annealing at 1400 °C results in decomposition of B-mullite to boron free mullite and ?-alumina. At 800 °C B-mullite appears to be stable over a period of at least 12 days. The mean thermal expansion coefficient was reduced by 15% upon incorporation of boron which makes the material technologically interesting.

Lührs, Hanna, E-mail: hanna.luehrs@uni-bremen.de [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany)] [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany); Fischer, Reinhard X. [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany)] [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany); Schneider, Hartmut [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany) [Universität Bremen, FB 5 Geowissenschaften, Klagenfurter Straße, D-28359 Bremen (Germany); Universität Köln, Institut für Kristallographie, Greinstraße 6, D-50939 Kölm (Germany)

2012-12-15T23:59:59.000Z

403

High linear-energy-transfer radiation can overcome radioresistance of glioma stem-like cells to low linear-energy-transfer radiation  

Science Journals Connector (OSTI)

......irradiation, especially thermal neutron irradiation. Boron-10 (10B) releases alpha (4He) and 7Li particles through...14 Kobayashi T , Kanda K. Analytical calculation of boron-10 dosage in cell nucleus for neutron capture therapy. Radiat......

Yuki Hirota; Shin-Ichiro Masunaga; Natsuko Kondo; Shinji Kawabata; Hirokazu Hirakawa; Hirohiko Yajima; Akira Fujimori; Koji Ono; Toshihiko Kuroiwa; Shin-Ichi Miyatake

2014-01-01T23:59:59.000Z

404

Boron containing multilayer coatings and method of fabrication  

DOE Patents (OSTI)

Hard coatings are fabricated from multilayer boron/boron carbide, boron carbide/cubic boron nitride, and boron/boron nitride/boron carbide, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron and boron carbide used in forming the multilayers are formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/boron carbide, and boron carbide/cubic boron nitride is produced by depositing alternate layers of boron, cubic boron nitride or boron carbide, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be of a discrete or a blended or graded composition. 6 figs.

Makowiecki, D.M.; Jankowski, A.F.

1997-09-23T23:59:59.000Z

405

Effect of boron on the deep donors (DX centers) in GaAs:Si  

SciTech Connect

We found that, when boron was introduced into GaAs:Si, the deep donors induced by pressure exceeding 20 kbar reported previously by M. Mizuta, M. Tachikawa, H. Kukimoto, and S. Minomura (J. Appl. Phys. 24, L143 (1985)) disappeared while new donor levels with reduced binding energies and capture barrier heights appeared. It is proposed that B atoms paired up with Si donor atoms and the resultant change in the short-range potential of the Si donor atoms depressed the capture barrier height of the pressure-induced deep donor.

Li, M.F.; Yu, P.Y.; Shan, W.; Hansen, W.; Weber, E.R.

1989-04-03T23:59:59.000Z

406

Muon capture rates within the projected QRPA  

E-Print Network (OSTI)

The conservation of the number of particles within the QRPA plays an important role in the evaluation muon capture rates in all light nuclei with A \\precsim 30 . The violation of the CVC by the Coulomb field in this mass region is of minor importance, but this effect could be quite relevant for medium and heavy nuclei studied previously. The extreme sensitivity of the muon capture rates on the 'pp' coupling strength in nuclei with large neutron excess when described within the QRPA is pointed out. We reckon that the comparison between theory and data for the inclusive muon capture is not a fully satisfactory test on the nuclear model that is used. The exclusive muon transitions are much more robust for such a purpose.

Danilo Sande Santos; Arturo R. Samana; Francisco Krmpoti?; Alejandro J. Dimarco

2012-03-03T23:59:59.000Z

407

Industry - ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

PartTec PartTec ORNL, PartTec Inc. Licensing Agreement ORNL and PartTec sign licensing agreement (Front) ORNL Deputy Director for Science & Technology Thomas Zacharia and PartTec CEO Herschel Workman. (Back) Bruce Hannan (SNS), PartTec production manager Craig Kline, Rick Riedel (SNS), Jason Hodges (SNS) and Ron Cooper (SNS). The SNS guys were on the development team. Representatives from Oak Ridge National Laboratory and PartTec, an Indiana-based firm, formally signed a licensing agreement Thursday, Aug. 12, to market an advanced neutron detector system developed for the Spallation Neutron Source. The Shifting Scintillator Neutron Detector can determine the time and position of captured neutrons, which enables researchers to obtain very accurate time-of-flight measurements.

408

The Motion Capture Pipeline.  

E-Print Network (OSTI)

?? Motion Capture is an essential part of a world full of digital effects in movies and games. Understanding the pipelines between software is a… (more)

Holmboe, Dennis

2008-01-01T23:59:59.000Z

409

Capturing Energy Upgrades  

Energy.gov (U.S. Department of Energy (DOE))

Provides an overview of how to capture the value of energy efficiency upgrades in the real estate market, from CNT Energy.

410

Reversible Acid Gas Capture  

SciTech Connect

Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

Dave Heldebrant

2009-08-01T23:59:59.000Z

411

Reversible Acid Gas Capture  

ScienceCinema (OSTI)

Pacific Northwest National Laboratory scientist David Heldebrant demonstrates how a new process called reversible acid gas capture works to pull carbon dioxide out of power plant emissions.

Dave Heldebrant

2012-12-31T23:59:59.000Z

412

Low energy neutron-proton interactions  

E-Print Network (OSTI)

There have been few measurements of cross sections for neutron-proton scattering and radiative capture below 1 MeV. Those measurements which do exist are at a small number of energies and are often inconsistent with ...

Daub, Brian (Brian Hollenberg)

2012-01-01T23:59:59.000Z

413

Design and testing of a boron carbide capsule for spectral-tailoring in mixed-spectrum reactors  

SciTech Connect

A boron carbide capsule has been designed and used for spectral-tailoring experiments at the TRIGA reactor at Washington State Univ.. Irradiations were conducted in pulsed mode and in continuous operation for up to 4 h. A cadmium cover was used to reduce thermal heating. The neutron spectrum calculated with the Monte Carlo N-particle transport code was found to be in good agreement with reactor dosimetry measurements using the STAY'SL computer code. The neutron spectrum resembles that of a fast reactor. The design of a capsule using boron carbide fully enriched in {sup 10}B shows that it is possible to produce a neutron spectrum similar to that of {sup 235}U fission. (authors)

Greenwood, L.R.; Wittman, R. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Pierson, B.P. [Univ. of Michigan, Ann Arbor, MI 48109 (United States); Metz, L.A.; Payne, R.; Finn, E.C.; Friese, J.I. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States)

2011-07-01T23:59:59.000Z

414

How Carbon Capture Works  

Energy.gov (U.S. Department of Energy (DOE))

Carbon capture, utilization and storage is a process that captures carbon dioxide emissions from sources like coal-fired power plants and either reuses or stores it so it will not enter the atmosphere. We'll break down the process step by step so you can learn how this technology can help us lower our carbon pollution.

415

Bamboo-like boron nitride nanotubes  

Science Journals Connector (OSTI)

......Full-length paper Bamboo-like boron nitride nanotubes Renzhi Ma Yoshio Bando Tadao Sato To...305-0044, Japan Bamboo-like boron nitride nanotubes (BN-NTs), synthesized from melamine...the temperature gradient applied in the nanotube growth process was considered as the......

Renzhi Ma; Yoshio Bando; Tadao Sato

2002-03-01T23:59:59.000Z

416

Resonance capture cross section of 207Pb  

E-Print Network (OSTI)

The radiative neutron capture cross section of 207Pb has been measured at the CERN neutron time of flight installation n_TOF using the pulse height weighting technique in the resolved energy region. The measurement has been performed with an optimized setup of two C6D6 scintillation detectors, which allowed us to reduce scattered neutron backgrounds down to a negligible level. Resonance parameters and radiative kernels have been determined for 16 resonances by means of an R-matrix analysis in the neutron energy range from 3 keV to 320 keV. Good agreement with previous measurements was found at low neutron energies, whereas substantial discrepancies appear beyond 45 keV. With the present results, we obtain an s-process contribution of 77(8)% to the solar abundance of 207Pb. This corresponds to an r-process component of 23(8)%, which is important for deriving the U/Th ages of metal poor halo stars.

C. Domingo-Pardo

2006-10-26T23:59:59.000Z

417

IMPACCT: Carbon Capture Technology  

SciTech Connect

IMPACCT Project: IMPACCT’s 15 projects seek to develop technologies for existing coal-fired power plants that will lower the cost of carbon capture. Short for “Innovative Materials and Processes for Advanced Carbon Capture Technologies,” the IMPACCT Project is geared toward minimizing the cost of removing carbon dioxide (CO2) from coal-fired power plant exhaust by developing materials and processes that have never before been considered for this application. Retrofitting coal-fired power plants to capture the CO2 they produce would enable greenhouse gas reductions without forcing these plants to close, shifting away from the inexpensive and abundant U.S. coal supply.

None

2012-01-01T23:59:59.000Z

418

Environment assisted electron capture  

E-Print Network (OSTI)

Electron capture by {\\it isolated} atoms and ions proceeds by photorecombination. In this process a species captures a free electron by emitting a photon which carries away the excess energy. It is shown here that in the presence of an {\\it environment} a competing non-radiative electron capture process can take place due to long range electron correlation. In this interatomic (intermolecular) process the excess energy is transferred to neighboring species. The asymptotic expression for the cross section of this process is derived. We demonstrate by explicit examples that under realizable conditions the cross section of this interatomic process can clearly dominate that of photorecombination.

Kirill Gokhberg; Lorenz S. Cederbaum

2009-11-09T23:59:59.000Z

419

Chaos and Tidal Capture  

E-Print Network (OSTI)

We review the tidal capture mechanism for binary formation, an important process in globular cluster cores and perhaps open cluster cores. Tidal capture binaries may be the precursors for some of the low-mass X-ray binaries observed in abundance in globular clusters. They may also play an important role in globular cluster dynamics. We summarize the chaos model for tidal interaction (Mardling 1995, ApJ, 450, 722, 732), and discuss how this affects our understanding of the circularization process which follows capture.

Rosemary A. Mardling

1995-12-07T23:59:59.000Z

420

Neutron Polarimetry  

Science Journals Connector (OSTI)

8 July 1993 research-article Neutron Polarimetry P. Jane Brown J. Bruce Forsyth Francis Tasset Zero-field neutron polarimetry is a technique which has...polarization analysis to be carried out in a neutron scattering experiment. The incident...

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Capture.PDF  

NLE Websites -- All DOE Office Websites (Extended Search)

Barriers for Carbon Capture, Storage and Sequestration Barriers for Carbon Capture, Storage and Sequestration Sarah M. Forbes, National Energy Technology Laboratory November, 2002 The success of carbon capture, storage and sequestration as a greenhouse gas mitigation strategy will be, in part, dependent on the regulatory framework used to govern its implementation. Creating a science-based regulatory framework that is designed with enough flexibility to encourage greenhouse gas offset activity, effective means of measuring the costs of taking action to reduce greenhouse gas emissions, and ample protection for human and ecosystem health may prove challenging. For the purposes of this paper we will assume that there is an existing incentive to capture, store and sequester carbon and focus on how to regulate the process. Accounting practices and

422

Introduction to Carbon Capture  

Science Journals Connector (OSTI)

Chapters 7–9 examine nontraditional separation technologies that in the most ideal sense may be considered carbon-neutral. The topics covered in these chapters include the role that algae plays in CO2 capture, CO

Prof. Jennifer Wilcox

2012-01-01T23:59:59.000Z

423

ATK - Supersonic Carbon Capture  

SciTech Connect

ATK and ACEnt Laboratories, with the help of ARPA-E funding, have taken an aerospace problem, supersonic condensation, and turned it into a viable clean energy solution for carbon capture.

Castrogiovanni, Anthony (ACEnT Laboratories, President and CEO) [ACEnT Laboratories, President and CEO; Calayag, Bon (ATK, Program Manager) [ATK, Program Manager

2014-03-05T23:59:59.000Z

424

Striving To Capture Carbon  

Science Journals Connector (OSTI)

Striving To Capture Carbon ... Energy ministers from around the world met in Washington, D.C., for three days earlier this month to wrestle with how to reenergize efforts to cut carbon emissions from coal-fired power plants. ... Their solution, not surprisingly, is a rapid acceleration of R&D for technologies that capture and sequester underground carbon dioxide emitted by power plants, refineries, and industrial manufacturers that burn fossil fuels. ...

JEFF JOHNSON

2013-11-25T23:59:59.000Z

425

Measurements of neutron-induced reactions in inverse kinematics  

E-Print Network (OSTI)

Neutron capture cross sections of unstable isotopes are important for neutron induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes.

René Reifarth; Yuri A. Litvinov

2013-12-13T23:59:59.000Z

426

RESULTS OF FIRST EXPERIMENTS ON NEUTRON GENERATION IN THE VITA NEUTRON SOURCE  

E-Print Network (OSTI)

as activation detector due to capture of epithermal neutrons by iodine also. Bubble detectors were used shell and reliably protected from magnetic fields and electromagnetic noises. Stability of the power

Taskaev, Sergey Yur'evich

427

BACKSCATTER GUAGE DESCRIPTION FOR INSPECTION OF NEUTRON ABSORBER AND UNIFORMITY  

SciTech Connect

This paper describes design, calibration, and testing of a dual He-3 detector neutron backscatter gauge for use in the Savannah River Site Mixed Oxide Fuel project. The gauge is demonstrated to measure boron content and uniformity in concrete slabs used in the facility construction.

Dewberry, R.; Gibbs, K.; Couture, A.

2012-05-23T23:59:59.000Z

428

Radiative muon capture  

Science Journals Connector (OSTI)

It is shown by relating the transition amplitude of radiative muon capture to that of radiative pion capture, that the transition amplitude of radiative muon capture proposed recently by Hwang and Primakoff differs from the others mainly by Low's counter terms. Despite the fact that the "original" transition amplitude does not violate seriously the conservation of the hadronic electromagnetic current, Low's counter terms, as introduced via Low's prescription to secure the presence of small conservation-of-hadronic-electromagnetic-current-breaking terms, are confirmed to be of numerical importance. Further, it is found in the "elementary-particle" treatment of radiative muon capture that the uncertainty arising from the nuclear structure can be reduced to become negligible. Therefore, an exclusive radiative muon capture experiment can in principle differentiate the Hwang-Primakoff theory from the others and yet provide a comprehensive test of partial conservation of axial-vector current.RADIOACTIVITY Theories of radiative muon capture, linearity hypothesis versus Low's prescription; nuclear structure and PCAC.

W -Y. P. Hwang

1980-07-01T23:59:59.000Z

429

Boron-10 Neutron Detectors for Helium-3 Replacement  

NLE Websites -- All DOE Office Websites (Extended Search)

to tell the difference between radiation emitted by nuclear materials and naturally occurring gamma radiation emitted by benign cargos, such as bananas. Finally, the United...

430

Porcelain enamel neutron absorbing material  

DOE Patents (OSTI)

A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compounds of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved.

Iverson, Daniel C. (Aiken, SC)

1990-01-01T23:59:59.000Z

431

Porcelain enamel neutron absorbing material  

DOE Patents (OSTI)

A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compound of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved. 2 figs.

Iverson, D.C.

1987-11-20T23:59:59.000Z

432

Carbon Capture Research and Development  

NLE Websites -- All DOE Office Websites (Extended Search)

Center Lawrence Berkeley National Laboratory Research Institute of Innovative Energy Carbon Capture Research and Development Carbon capture and storage from fossil-based power...

433

Booster Subharmonic RF Capture Design  

NLE Websites -- All DOE Office Websites (Extended Search)

Booster Subharmonic RF Capture Design 1 Booster Subharmonic RF Capture Design Nicholas S. Sereno, 7102002 1.0 Motivation and Requirements Successful operation of the APS storage...

434

Preliminary design of a GD?NCT neutron beam based on compact D?T neutron source  

Science Journals Connector (OSTI)

......J. Roentgenol. 36 , 1-13 (1936). 2. Sweet, W. H. and Javid, M. The possible use of slow neutrons plus boron-10 in the therapy of intracranial tumors. Trans. Am. neurol. Ass. 76 , 60-63 (1951). 3. Sweet, W. H., Soloway......

N. Cerullo; J. Esposito; D. Bufalino; A. Mastrullo; L. Muzi; S. Palmerini

2005-12-20T23:59:59.000Z

435

Transmutation of Elements through Capture of Electrons by Nuclei  

E-Print Network (OSTI)

A proton can capture an electron and turn into a neutron provided the electron has a kinetic energy of 0.782 MeV or more.An element of the Periodic Table can change into another on being exposed to such high energy electrons.

A. Mukherji

2011-05-11T23:59:59.000Z

436

Neutron Production, Neutron Facilities and Neutron Instrumentation  

Science Journals Connector (OSTI)

...Mexico, 87545, U.S.A, e-mail: sven@lanl.gov Hans-Georg Priesmeyer Geesthacht Neutron Scattering Facility, GKSS Research Center, 21502 Geesthacht, Germany, e-mail: hans-georg.priesmeyer@gkss.de NEUTRON GENERATION The...

Sven C. Vogel; Hans-Georg Priesmeyer

437

Isotope ratio determination in boron analysis  

Science Journals Connector (OSTI)

Traditionally, boron (B) isotope ratios have been determined using thermal ionization...+, Cs+, or O-...for analyte ionization. TIMS can be used in negative or positive ion modes with high sensitivity and precisi...

Ram N. Sah; Patrick H. Brown

1998-12-01T23:59:59.000Z

438

Abrasive slurry composition for machining boron carbide  

DOE Patents (OSTI)

An abrasive slurry particularly suited for use in drilling or machining boron carbide consists essentially of a suspension of boron carbide and/or silicon carbide grit in a carrier solution consisting essentially of a dilute solution of alkylaryl polyether alcohol in octyl alcohol. The alkylaryl polyether alcohol functions as a wetting agent which improves the capacity of the octyl alcohol for carrying the grit in suspension, yet without substantially increasing the viscosity of the carrier solution.

Duran, Edward L. (Santa Fe, NM)

1985-01-01T23:59:59.000Z

439

Average resonance capture study of Te124  

Science Journals Connector (OSTI)

An average resonance capture study of Te124 was carried out by bombarding samples of Te123 with 2- and 24-keV neutron beams. The complete set of 0+, 1+, 2+ states disclosed by the experiment is consistent with the data of Robinson, Hamilton, and Snelling, demonstrating that there are no undetected states of these spins (especially 0+ states) below about 2500 keV. In particular, proposed 0+ levels at 1156 and 1290 keV are ruled out. This impacts various attempted interpretations in terms of intruder states, U(5), and O(6) symmetries.

R. F. Casten; J.-Y. Zhang; B.-C. Liao

1991-07-01T23:59:59.000Z

440

Neutron Reflectivity  

Science Journals Connector (OSTI)

Neutron Reflectivity ... This article is part of the Neutron Reflectivity special issue. ... The articles in this special issue on neutron reflectivity cover a broad range of the applications of this technique and the related X-ray and neutron scattering experiments of SAXS, SANS, GISAXS, and GISANS. ...

Jeffrey Penfold

2009-03-31T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Basic features of boron isotope separation by SILARC method in the two-step iterative static model  

Science Journals Connector (OSTI)

Boron isotopes have a broad spectrum of applications in industry. Naturally occurring boron consists of two stable isotopes—19.9 % of boron-10 and 81.1 % of boron-11. A useful property of pure boron-10 isotopes a...

K. A. Lyakhov; H. J. Lee

2013-05-01T23:59:59.000Z

442

CAPTURE DOCUMENT ORAUTEAM  

Office of Legacy Management (LM)

DATA DATA CAPTURE DOCUMENT ORAUTEAM ---- Dose Reconstruction ~v~:7 DISCOVERY AND REVIEW dA'~ Project for NIOSH The attached document may contain Privacy Act data. This information is protected by the Privacy Act, 5 U.S.C. §552a; disclosure to any third party without written consent of the individual to whom the information pertains is strictly prohibited. Data Capture Team or Other ORAU Team Member Capturing Data: Complete all information that applies to the data/document being submitted lor uploading to the Site Research Database (SRDB), attach this lonm to the lront olthe document, and send to: ORAU Team, Attention: SRDB Uploading, 4850 Smith Rd., Suite 200, Cincinnati, Ohio 45212. I ~ -!-R"e"guestor and Reviewer 1. Data Requestor: RSET Group 2. Reviewer Name (if different from Requestor): Don Morris 3. Target Data: Document Specified by Requestor Any relevant

443

About Neutrons  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron Basics Neutron Basics A neutron is one of the fundamental particles that make up matter. This uncharged particle exists in the nucleus of a typical atom, along with its positively charged counterpart, the proton. Protons and neutrons each have about the same mass, and both can exist as free particles away from the nucleus. In the universe, neutrons are abundant, making up more than half of all visible matter. Find Out What a Neutron Is Youtube icon Properties of Neutrons How Can Neutrons Be Used for Research? Image of glucose movement in plants Neutron imaging techniques have been able to determine the precise movement of glucose in plants. This knowledge can help scientists better understand how biomass can be efficiently converted into fuel. Neutrons have many properties that make them ideal for certain types of

444

Motion Capture Technologies Jessica Hodgins  

E-Print Network (OSTI)

a few dof) #12;Production Pipeline #12;What is captured? · Dynamic motions? House of Moves #12;What is captured? · Scale? Motion Analysis #12;What is captured? · Non-rigid objects? House of Moves #12;What is captured? · Props often cause problems ­ Ball in pingpong ­ Fly fishing ­ Sword · Passive behaviors

Treuille, Adrien

445

Adiabatic capture and debunching  

SciTech Connect

In the study of beam preparation for the g-2 experiment, adiabatic debunching and adiabatic capture are revisited. The voltage programs for these adiabbatic processes are derived and their properties discussed. Comparison is made with some other form of adiabatic capture program. The muon g-2 experiment at Fermilab calls for intense proton bunches for the creation of muons. A booster batch of 84 bunches is injected into the Recycler Ring, where it is debunched and captured into 4 intense bunches with the 2.5-MHz rf. The experiment requires short bunches with total width less than 100 ns. The transport line from the Recycler to the muon-production target has a low momentum aperture of {approx} {+-}22 MeV. Thus each of the 4 intense proton bunches required to have an emittance less than {approx} 3.46 eVs. The incoming booster bunches have total emittance {approx} 8.4 eVs, or each one with an emittance {approx} 0.1 eVs. However, there is always emittance increase when the 84 booster bunches are debunched. There will be even larger emittance increase during adiabatic capture into the buckets of the 2.5-MHz rf. In addition, the incoming booster bunches may have emittances larger than 0.1 eVs. In this article, we will concentrate on the analysis of the adiabatic capture process with the intention of preserving the beam emittance as much as possible. At this moment, beam preparation experiment is being performed at the Main Injector. Since the Main Injector and the Recycler Ring have roughly the same lattice properties, we are referring to adiabatic capture in the Main Injector instead in our discussions.

Ng, K.Y.; /Fermilab

2012-03-01T23:59:59.000Z

446

Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances  

SciTech Connect

Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5 20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,g)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,g)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

Thompson, I J [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Escher, Jutta E [ORNL] [ORNL; Arbanas, Goran [ORNL] [ORNL

2013-01-01T23:59:59.000Z

447

Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances  

Science Journals Connector (OSTI)

Abstract Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5–20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,?)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,?)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

I.J. Thompson; J.E. Escher; G. Arbanas

2014-01-01T23:59:59.000Z

448

Research Highlights | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron/Proton Capture Neutron/Proton Capture Beam Line 13 Fuels Discovery Fever for Fundamental Physicists Research Contact: Geoff Greene June 2011, Written by Agatha Bardoel Serpil Kucuker Dogan (left) and Matthew Musgrave prepare a helium-3 cooling cell that is used to measure the angle at which the neutron beam strikes the liquid hydrogen sample. The simplest, most sensible " Big Bang" universe, theoretical physicists believe, would be one in which equal numbers of particles and antiparticles are formed in pairs. As the universe cools, most of these particles would encounter their antiparticles, and they would annihilate. "In many ways, the most reasonable universe would be one in which there is no matter," says the University of Tennessee's Dr. Geoff Greene.

449

A Boron Subphthalocyanine Polymer: Poly(4-methylstyrene)-co-poly(phenoxy boron subphthalocyanine)  

Science Journals Connector (OSTI)

A Boron Subphthalocyanine Polymer: Poly(4-methylstyrene)-co-poly(phenoxy boron subphthalocyanine) ... Deuterated chloroform with 0.05% (v/v) tetramethylsilane (TMS) was purchased from Cambridge Isotope Laboratories (St. ... Before additional effort was put into obtaining a BsubPc vinyl monomer we first wanted to determine whether or not the BsubPc group is a radical scavenger. ...

Jeremy D. Dang; Jessica D. Virdo; Benoît H. Lessard; Elijah Bultz; Andrew S. Paton; Timothy P. Bender

2012-09-28T23:59:59.000Z

450

Boron isotope ratios in commercial produce and boron-10 foliar and hydroponic enriched plants  

Science Journals Connector (OSTI)

Boron isotope ratios in commercial produce and boron-10 foliar and hydroponic enriched plants ... The Absorption and Tissue Distribution of Selenium from High-Selenium Broccoli Are Different from Selenium from Sodium Selenite, Sodium Selenate, and Selenomethionine As Determined in Selenium-Deficient Rats ...

Richard A. Vanderpool; Phyllis E. Johnson

1992-03-01T23:59:59.000Z

451

4. Heterogeneous Energy Deposition from External Radiations  

Science Journals Connector (OSTI)

......irradiation yielding large values of energy absorbed in regions of microscopic dimensions around the neutron-capture site. Boron-10, for example, has a very large cross section for thermal-neutron capture (Zamenhof et al., 1999) compared to......

4. Heterogeneous Energy Deposition from External Radiations

2011-12-01T23:59:59.000Z

452

Report 86  

Science Journals Connector (OSTI)

......irradiation yielding large values of energy absorbed in regions of microscopic dimensions around the neutron- capture site. Boron-10, for example, has a very large cross section for thermal-neutron capture (Zamenhof et al., 1999) compared to......

Report 86

2011-12-01T23:59:59.000Z

453

Carbon Smackdown: Carbon Capture  

SciTech Connect

In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

Jeffrey Long

2010-07-12T23:59:59.000Z

454

Muon capture in hydrogen  

E-Print Network (OSTI)

Theoretical difficulties in reconciling the measured rates for ordinary and radiative muon capture are discussed, based on heavy-baryon chiral perturbation theory. We also examine ambiguity in our analysis due to the formation of p$\\mu$p molecules in the liquid hydrogen target.

S. Ando; F. Myhrer; K. Kubodera

2001-10-30T23:59:59.000Z

455

Uranium Neutron Coincidence Collar Model Utilizing 3He  

SciTech Connect

The Department of Energy Office of Nuclear Safeguards (NA-241) is supporting the project 'Coincidence Counting With Boron-Based Alternative Neutron Detection Technology' at Pacific Northwest National Laboratory (PNNL) for development of an alternative neutron coincidence counter. The goal of this project is to design, build and demonstrate a boron-lined proportional tube based alternative system in a configuration typically used for 3He-based coincidence counter applications. The specific application selected for boron-lined tube replacement in this project was one of the Uranium Neutron Coincidence Collar (UNCL) designs. This report, providing results for model development of a UNCL, is a deliverable under Task 2 of the project. The current UNCL instruments utilize 3He tubes. As the first step in developing and optimizing a boron-lined proportional counter based version of the UNCL, models of eight different 3He-based UNCL detectors currently in use were developed and evaluated. A comparison was made between the simulated results and measured efficiencies for those systems with values reported in the literature. The reported experimental measurements for efficiencies and die-away times agree to within 10%.

Siciliano, Edward R.; Rogers, Jeremy L.; Schweppe, John E.; Lintereur, Azaree T.; Kouzes, Richard T.

2012-07-30T23:59:59.000Z

456

Sample preparation for isotopic determination of boron in clay sediments  

Science Journals Connector (OSTI)

The procedures of sample preparation for isotopic determination of boron in clay sediments is very cumbersome, by ... experiments were carried out. In this paper, boron in clay sediments was extracted with HCl .....

Yanling Zhang; Yingkai Xiao; Yunqi Ma; Qin Zhuge…

2013-06-01T23:59:59.000Z

457

Boron-Nitride Nanotubes Show Potential in Cancer Treatment |...  

NLE Websites -- All DOE Office Websites (Extended Search)

Boron-Nitride Nanotubes Show Potential in Cancer Treatment NEWPORT NEWS, VA, April 26 - A new study has shown that adding boron-nitride nanotubes to the surface of cancer cells can...

458

Neutron-Neutron Scattering Length  

Science Journals Connector (OSTI)

The final-state interaction of the two neutrons from the reaction ?-+d?2n+? has a pronounced and distinctive effect on the momentum spectrum of the outgoing particles. In particular, the neutron spectrum is sharply peaked in the neighborhood of 2 Mev, with a shape that is quite sensitive to the strength of the nn interaction. In the region of this peak, the relative neutron-neutron momentum is so small that the nn interaction is completely characterized by its scattering length. Hence it is proposed that a measurement of the shape of the neutron spectrum from this reaction may provide a convenient means of measuring the neutron-neutron scattering length. Neutron spectra are calculated in an impulse approximation, for several assumed values of the scattering length. It appears from their shapes that, in this way, present neutron-detection techniques should be capable of determining the scattering length to within 25%.

Kirk W. McVoy

1961-03-01T23:59:59.000Z

459

Electrons from Muon Capture  

Science Journals Connector (OSTI)

We have searched for the process ?-+p?p+e- or ?-+n?n+e- for ? mesons stopped in a Cu target. Scintillation counters were employed to detect the electrons from the process. No counts attributable to the electrons were obtained and we place an upper limit of ?5×10-4 for the relative rate of this process to that for the usual nuclear capture reaction.

J. Steinberger and Harry B. Wolfe

1955-12-01T23:59:59.000Z

460

Radiative Muon Capture  

Science Journals Connector (OSTI)

The theory of radiative muon capture is developed. The discussion includes both parity conserving and nonconserving effects. The Gell-Mann weak magnetic term and the induced pseudoscalar are included, along with comparable relativistic effects in the nucleons. The theory is applied to light nuclei and especially to the radiative Godfrey reaction ?-+C126??+?+B125. An experiment to detect the induced pseudoscalar directly is proposed.

Jeremy Bernstein

1959-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "boron neutron capture" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Neutron skins and neutron stars  

SciTech Connect

The neutron-skin thickness of heavy nuclei provides a fundamental link to the equation of state of neutron-rich matter, and hence to the properties of neutron stars. The Lead Radius Experiment ('PREX') at Jefferson Laboratory has recently provided the first model-independence evidence on the existence of a neutron-rich skin in {sup 208}Pb. In this contribution we examine how the increased accuracy in the determination of neutron skins expected from the commissioning of intense polarized electron beams may impact the physics of neutron stars.

Piekarewicz, J. [Department of Physics, Florida State University, Tallahassee, FL 32306-4350 (United States)

2013-11-07T23:59:59.000Z

462

Neutron scattering  

Science Journals Connector (OSTI)

... likely to be able to contribute to many different branches of chemistry and secondly because neutron ...neutronscattering ...

A. J. Leadbetter

1977-12-01T23:59:59.000Z

463

A system to deposit boron films (boronization) in the DIII-D tokamak  

SciTech Connect

A system has been added to the D3-D tokamak to coat its plasma facing surfaces with a film of boron using diborane gas. The system includes special health and safety equipment for handling the diborane gas which is toxic and inflammable. The purpose of the boron film is to reduce the levels of impurity atoms in the D3-D plasmas. Experiments following the application of the boron film in D3-D have led to significant reductions in plasma impurity levels and the observation of a new, very high confinement regime. 9 refs., 1 fig.

Hodapp, T.R.; Jackson, G.L.; Phillips, J.; Holtrop, K.L.; Petersen, P.I. (General Atomics, San Diego, CA (United States)); Winter, J. (Forschungszentrum Juelich GmbH (Germany). Inst. fuer Plasmaphysik)

1991-09-01T23:59:59.000Z

464

Muon Capture and Nuclear Structure  

Science Journals Connector (OSTI)

We have studied the fundamental muon-nucleon interaction from the muon capture in gaseous and molecular hydrogen and ... problem upon the knowledge of the former from muon captures in C12 and O16.

M. Morita; H. Ohtsubo; A. Fujii

1970-01-01T23:59:59.000Z

465

Neutron guide  

DOE Patents (OSTI)

A neutron guide in which lengths of cylindrical glass tubing have rectangular glass plates properly dimensioned to allow insertion into the cylindrical glass tubing so that a sealed geometrically precise polygonal cross-section is formed in the cylindrical glass tubing. The neutron guide provides easier alignment between adjacent sections than do the neutron guides of the prior art.

Greene, Geoffrey L. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

466

Neutron Diffraction  

Science Journals Connector (OSTI)

22 February 1949 research-article Neutron Diffraction G. E. Bacon J. Thewlis The problem of neutron diffraction by crystals is treated by analogy...deals with a comparison between X-ray and neutron diffraction and it is shown that quantitatively...

1949-01-01T23:59:59.000Z

467

Decreasing the leachibility of boron wood preservatives  

E-Print Network (OSTI)

. Recommendation for Further Research. 64 66 LITERATURE CITED. 68 APPENDIX A APPENDIX B 104 VITA. 147 LIST OF FIGURES FIGURE Page 1 World boron sources. 2 World boron production 75 76 Boric acid retention in conditioned southern pine wood samples 77...-block test on soil from forested area ? test fungus Lenti nus 1epi deus. 93 20 Weight loss for boric acid+PEG-600 treated blocks put through soil-block test on soil from agricultural area ? test fungus Pari a montico1a FIGURE Page 21 Weight loss...

Gezer, Engin Derya

2012-06-07T23:59:59.000Z

468

Localization and Therapeutic Potential of Tritiated Tetracycline in Rodent Tumors  

Science Journals Connector (OSTI)

...Gillchriest, W. C., and Shaw, D. H. Effectiveness of Boronated Tetracy cline Antibiotic Derivatives (TZB2)as the Boron-10 Carrier in Neutron Capture Therapy. Oncology, 27: 97-104, 1973. 9. Gordon, B. Oxytetracycline, A Medium for...

Richard C. Davis; Paula Wood; Mortimer L. Mendelsohn

1977-12-01T23:59:59.000Z

469

Capturing the Daylight Dividend  

SciTech Connect

Capturing the Daylight Dividend conducted activities to build market demand for daylight as a means of improving indoor environmental quality, overcoming technological barriers to effective daylighting, and informing and assisting state and regional market transformation and resource acquisition program implementation efforts. The program clarified the benefits of daylight by examining whole building systems energy interactions between windows, lighting, heating, and air conditioning in daylit buildings, and daylighting's effect on the human circadian system and productivity. The project undertook work to advance photosensors, dimming systems, and ballasts, and provided technical training in specifying and operating daylighting controls in buildings. Future daylighting work is recommended in metric development, technology development, testing, training, education, and outreach.

Peter Boyce; Claudia Hunter; Owen Howlett

2006-04-30T23:59:59.000Z

470

How Carbon Capture Works | Department of Energy  

Energy Savers (EERE)

past two decades. Carbon capture, utilization and storage (CCUS) -- also referred to as carbon capture, utilization and sequestration -- is a process that captures carbon dioxide...

471

Leaching of boron from coal ash  

Science Journals Connector (OSTI)

Leaching of boron from coal ash ... First High-Resolution 11B Nuclear Magnetic Resonance (NMR) Spectra of Coal Fly Ash by Satellite-Transition Magic Angle Spinning (STMAS) NMR ... First High-Resolution 11B Nuclear Magnetic Resonance (NMR) Spectra of Coal Fly Ash by Satellite-Transition Magic Angle Spinning (STMAS) NMR ...

James A. Cox; Gary L. Lundquist; Andrzej Przyjazny; C. David Schmulbach

1978-06-01T23:59:59.000Z

472

Tetrahedral boron in naturally occurring tourmaline  

SciTech Connect

Evidence for boron in both trigonal and tetrahedral coordination has been found in {sup 11}B magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) spectra of natural, inclusion-free specimens of aluminum-rich lithian tourmaline from granitic pregmatites.

Tagg, S.L.; Cho, H. [Pacific Northwest National Lab., Richland, WA (United States). Environmental Molecular Sciences Lab.; Dyar, M.D. [Mount Holyoke Coll., South Hadley, MA (United States). Dept. of Geology and Geography; Grew, E.S. [Univ. of Maine, Orono, ME (United States). Dept. of Geological Sciences

1999-09-01T23:59:59.000Z

473

Neutron skins and neutron stars  

Science Journals Connector (OSTI)

Background: The neutron skin of a heavy nucleus as well as many neutron-star properties are highly sensitive to the poorly constrained density dependence of the symmetry energy.Purpose: To provide for the first time meaningful theoretical errors and to assess the degree of correlation between the neutron-skin thickness of 208Pb and several neutron-star properties.Methods: A proper covariance analysis based on the predictions of an accurately calibrated relativistic functional “FSUGold” is used to quantify theoretical errors and correlation coefficients.Results: We find correlation coefficients of nearly 1 (or ?1) between the neutron-skin thickness of 208Pb and a host of observables of relevance to the structure, dynamics, and composition of neutron stars.Conclusions: We suggest that a follow-up Lead Radius Experiment (PREX) measurement, ideally with a 0.5% accuracy, could significantly constrain the equation of state of neutron-star matter.

F. J. Fattoyev and J. Piekarewicz

2012-07-05T23:59:59.000Z

474

Neutron Scattering Tutorials | Neutron Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron Scattering Tutorials SHARE Neutron Scattering Tutorials The following lectures were presented at the 2011 and 2010 National School on Neutron & X-Ray Scattering. This...

475

Motion capture och skräck; Motion capture and horror.  

E-Print Network (OSTI)

?? Det här arbetet syftade till att undersöka om de skakningar och ryck som uppstår vid en dålig motion capture-inspelning, kan användas till fördel i… (more)

Åsén, Kristina Helene

2014-01-01T23:59:59.000Z

476

Radial elasticity of multi-walled boron nitride nanotubes  

SciTech Connect

We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

Michael W. Smith, Cheol Park, Meng Zheng, Changhong Ke ,In-Tae Bae, Kevin Jordan

2012-02-01T23:59:59.000Z

477

Microstructural characterization of superalloy 718 with boron and phosphorus additions  

SciTech Connect

Boron and phosphorus additions are known to improve the stress rupture properties of IN-718. One possible mechanism to explain this property improvement relies on the boron and phosphorus additions slowing down the growth of {gamma}{double_prime} and {gamma}{prime} precipitates during high temperature service or aging. However, atom probe analysis found no segregation of boron and phosphorus to {gamma}-{gamma}{double_prime} or to {gamma}-{gamma}{prime} interfaces in the alloys with the high boron and high phosphorus levels. No difference in growth rates were found by transmission electron microscopy in the sizes of the {gamma}{double_prime} or {gamma}{prime} in alloys with high phosphorus and high boron as compared to commercial alloys and to alloys with even lower levels of phosphorus and boron. Atom probe analysis further found that much of the phosphorus, boron, and carbon segregated to grain boundaries. Creep curves comparing the alloys with high levels of phosphorus and boron and alloys with low levels of phosphorus and boron show a large difference in strain rate in the first hours of the test. These results suggest that the boron and phosphorus may have a direct effect on dislocation mobility by some pinning mechanism.

Horton, J.A.; McKamey, C.G.; Miller, M.K. [Oak Ridge National Lab., TN (United States); Cao, W.D.; Kennedy, R.L. [Teledyne Allvac, Monroe, NC (United States)

1997-06-01T23:59:59.000Z

478

Fragment capture device  

DOE Patents (OSTI)

A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point of the solid fragment is located within a cavity at least partially enclosed by the array of bars.

Payne, Lloyd R. (Los Lunas, NM); Cole, David L. (Albuquerque, NM)

2010-03-30T23:59:59.000Z

479

Neutron Scattering  

Science Journals Connector (OSTI)

... Magnetic Neutron Diffraction By Yurii A. Izyumov and Ruslan P. Ozerov. Translated from the Russian. ... York; Heydon: London, June 1970.) 350s; $37.50; 150 DM.

G. L. SQUIRES

1970-12-05T23:59:59.000Z

480

The capture into parametric autoresonance  

E-Print Network (OSTI)

In this work we show that the capture into parametric resonance may be explained as the pitchfork bifurcation in the primary parametric resonance equation. We prove that the solution close to the moment of the capture is described by the Painleve-2 equation. We obtain the connection formulas for the asymptotic solution of the primary parametric resonance equation before and after the capture using the matching of the asymptotic expansions.

O M Kiselev; S G Glebov

2005-11-04T23:59:59.000Z