californium 254: Topics by WorldWideScience.org

Sample records for californium 254

Magnetism in californium

International Nuclear Information System (INIS)

Moore, J.R.

1988-03-01

A SQUID-based magnetic susceptometer has been constructed for studying small radioactive samples at temperatures below 350 K and in magnetic fields up to 50 kilogauss. The device has been used to study californium (element 98) in a number of solid-state forms: the dhcp metal, several oxides (Cf 2 O 3 in both the bcc and monoclinic structures, Cf 7 O 12 , CfO 2 and BaCfO 3 ), several monopnictides (CfN, CfAs and CfSb) and the trichloride (in both the hexagonal and orthorhombic structures). All of these materials were studied in polycrystalline form, and hexagonal CfCl 3 was studied in single-crystal form as well. The susceptometer has the sensitivity to measure samples containing less than 10 micrograms of californium. The magnetic susceptibilities of all of the californium materials at temperatures above about 100 K are described well by the Curie-Weiss relationship. This behavior is consistent with the assumption that the magnetic 5f electrons are localized and that the paramagnetic behavior can be interpreted in terms of the properties of the free ion. The measured values of the effective paramagnetic moment, μ/sub eff/, for all the californium materials that were studied are reasonably consistent with theoretical values based on intermediate coupling models. All of the californium materials showed some indications of cooperative magnetic effects. The dhcp metal was observed to order ferromagnetically at 52 K, and all of the californium compounds studied showed signs of antiferromagnetic ordering, mostly at temperatures below 25 K. 91 refs., 50 figs., 19 tabs
Medical applications of californium-252

International Nuclear Information System (INIS)

Oliver, G.D. Jr.

1975-01-01

Primarily, californium-252 sources have been utilized in medicine for the treatment of neoplastic lesions. For five years, a coordinated effort between several cancer research institutions and national laboratories has developed the necessary physics, radiobiology, and engineering skills to establish an evaluation program for californium. Several more years of combined effort are required before it is known whether californium therapy is as good as or better than conventional therapy with sources like radium. Recently, development of diagnostic applications of californium in medicine has received attention. Studies comparing neutron decay activation analysis versus prompt capture gamma ray analysis are in progress. A hopeful application of prompt analysis with reasonable quantities (200 μg) of californium is the elemental analysis of bone in the human body. (U.S.)
Californium-252 progress, report No. 7, April 1971

Energy Technology Data Exchange (ETDEWEB)

1971-12-31

This report contains discusses of the following topics on Californium-252: First sales of californium-252; encapsulation services discussed; three new participants in market evaluation program; summer training programs to use californium; Californium-252 shipping casks available; Californium-252 questions and answers, radiotherapy; neutron radiography; natural resources exploration; nuclear safeguards; process control; dosimetry; neutron radiography; neutron shielding; and nuclear safeguards.
Radiography using californium-252 neutron sources

International Nuclear Information System (INIS)

Ray, J.W.

1975-01-01

The current status in the technology of neutron radiography using californium-252 neutron sources is summarized. Major emphasis is on thermal neutron radiography since it has the widest potential applicability at the present time. Attention is given to four major factors which affect the quality and useability of thermal neutron radiography: source neutron thermalization, neutron beam extraction geometry, neutron collimator dimensions, and neutron imaging methods. Each of these factors has a major effect on the quality of the radiographs which are obtained from a californium source neutron radiography system and the exposure times required to obtain the radiographs; radiograph quality and exposure time in turn affect the practicality of neutron radiography for specific nondestructive inspection applications. A brief discussion of fast neutron radiography using californium-252 neutron sources is also included. (U.S.)
Historical review of californium-252 discovery and development

International Nuclear Information System (INIS)

Stoddard, D.H.

1985-01-01

This paper discusses the discovery and history of californium 252. This isotope may be synthesized by irradiating plutonium 239, plutonium 242, americium 243, or curium 244 with neutrons in a nuclear reactor. Various experiments and inventions involving 252 Cf conducted at the Savannah River Plant are discussed. The evolution of radiotherapy using californium 252 is reviewed
Californium-252 sales and loans at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

King, L.J.

1987-01-01

The production and distribution in the United States of 252 Cf has recently been consolidated at the Oak Ridge National Laboratory (ORNL). The 252 Cf Industrial Sales/Loan Program and the 252 Cf University Load Program, which were formerly located at the Savannah River Plant (SRP), have been combined with the californium production and distribution activities of the Transuranium Element Production Program at ORNL. Californium-252 is sold to commercial users in the form of bulk californium oxide, palladium-californium alloy pellets, or alloy wires. Neutron source capsules, which are fabricated for loans to DOE or other US government agencies, are still available in all forms previously available. The consolidation of all 252 Cf distribution activities at the production site is expected to result in better service to users. In particular, customers for neutrons sources will be ale to select from a wider range of neutron source forms, including custom designs, through a single contact point
Fabrication of californium-252 sources in the United Kingdom

International Nuclear Information System (INIS)

Ainsworth, A.; Brady, M.W.; Thornett, W.H.

1975-01-01

The advent of californium-252 in weighable quantities and at a reasonable price has caused some rethinking among neutron source suppliers. To explore this market the Radiochemical Center Ltd. has purchased 2 mg of californium-252, and subdivided this into a wide range of sources. To take advantage of its high specific neutron emission, a small double welded stainless steel capsule 7.8mm diameter x 10mm high was chosen for stock sources and this entailed the use of a microdispensing technique which had to be specially developed. The apparatus and procedure for subdividing milligram amounts of californium-252 are described. Some details of our experience in processing these one milligram shipments are given. 100 sources with activities from 200 microgram to 0.01 microgram have been produced. Losses have been small. Measurement of neutron spectra gamma spectra and dose rates from encapsulated sources has confirmed published data. Though it is early days, little industrial interest in californium-252 sources has been detected, most of the sources have so far been required for research into activation analysis and two examples of this are given. (U.S.)
Biomedical neutron research at the Californium User Facility for neutron science

International Nuclear Information System (INIS)

Martin, R.C.; Byrne, T.E.; Miller, L.F.

1997-01-01

The Californium User Facility for Neutron Science has been established at Oak Ridge National Laboratory (ORNL). The Californium User Facility (CUF) is a part of the larger Californium Facility, which fabricates and stores compact 252 Cf neutron sources for worldwide distribution. The CUF can provide a cost-effective option for research with 252 Cf sources. Three projects at the CUF that demonstrate the versatility of 252 Cf for biological and biomedical neutron-based research are described: future establishment of a 252 Cf-based neutron activation analysis system, ongoing work to produce miniature high-intensity, remotely afterloaded 252 Cf sources for tumor therapy, and a recent experiment that irradiated living human lung cancer cells impregnated with experimental boron compounds to test their effectiveness for boron neutron capture therapy
Biomedical neutron research at the Californium User Facility for Neutron Science

International Nuclear Information System (INIS)

Martin, R.C.; Byrne, T.E.; Miller, L.F.

1998-01-01

The Californium User Facility for Neutron Science has been established at Oak Ridge National Laboratory (ORNL). The Californium User Facility (CUF) is a part of the larger Californium Facility, which fabricates and stores compact 252 Cf neutron sources for worldwide distribution. The CUF can provide a cost-effective option for research with 252 Cf sources. Three projects at the CUF that demonstrate the versatility of 252 Cf for biological and biomedical neutron-based research are described: future establishment of a 252 Cf-based neutron activation analysis system, ongoing work to produce miniature high-intensity, remotely afterloaded 252 Cf sources for tumor therapy, and a recent experiment that irradiated living human lung cancer cells impregnated with experimental boron compounds to test their effectiveness for boron neutron capture therapy. (author)
Californium Multiplier. Part I. Design for neutron radiography

International Nuclear Information System (INIS)

Crosbie, K.L.; Preskitt, C.A.; John, J.; Hastings, J.D.

1982-01-01

The Californium Multiplier (CFX) is a subcritical assembly of enriched uranium surrounding a californium-252 neutron source. The function of the CFX is to multiply the neutrons emitted by the source to a number sufficient for neutron radiography. The CFX is designed to provide a collimated beam of thermal neutrons from which the gamma radiation is filtered, and the scattered neutrons are reduced to make it suitable for high resolution radiography. The entire system has inherent safety features, which provide for system and personnel safety, and it operates at moderate cost. In Part I, the CFX and the theory of its operation are described in detail. Part II covers the performance of the Mound Facility CFX
Californium-252 radiotherapy sources for interstitial afterloading

International Nuclear Information System (INIS)

Permar, P.H.; Walker, V.W.

1976-01-01

Californium-252 neutron sources for interstitial afterloading were developed to investigate the value of this radionuclide in cancer therapy. Californium-252 seed assemblies contain essentially point sources of 252 Cf permanently sealed on 1-cm centers within a flexible plastic tube. The seed assemblies are fabricated with remotely operated, specially designed machines. The fabrication process involves the production of a Pt-10 percent Ir-clad wire with a 252 Cf 2 O 3 -Pd cermet core. The wire is swaged and drawn to size, cut to length, and welded in a Pt-10 percent Ir capsule 0.8 mm in diameter and 6 mm long. Each seed capsule contains approximately 0.5 microgram of 252 Cf. Because the effective half-life of 252 Cf is 2.6 years, the seed assemblies are not disposable and must be reused until their activities have decreased to unsuitable levels. The flexible plastic components must therefore have sufficient resistance to radiation damage to survive the neutron-plus-gamma radiation from 252 Cf. On the basis of accelerated irradiation tests with a large 252 Cf source, a recently developed fluoropolymer, ''Tefzel'' (trademark of E. I. du Pont de Nemours and Company) has adequate radiation resistance for this application. Californium-252 seed assembly systems are loaned by the United States Energy Research and Development Administration for clinical investigations under a protocol of the Radiation Therapy Oncology Group, U.S. National Cancer Institute
Uranium standards for Californium Shuffler

International Nuclear Information System (INIS)

Gibbs, A.; Boynton, S.P.

1978-10-01

The Laboratories Department analyzed pieces of a U-Al log which were to be canned and used as a set of standards for the nondestructive Californium Shuffler instrument. Evaluation of this instrument is part of an on-going Safeguards Program and is a joint project between LASL and SRP. A U-Al casting of a nominal 30% to 70% composition was made with enriched uranium (56 wt % 235 U). The log was 6 in. in diameter and approximately 2 ft long. A 1/4-in. slice was made before and after each 1-in. slice taken for use as a standard. The 1-in. slices were scanned nondestructively by collimated gamma pulse height analysis. The 1/4-in. slices were divided into quadrants and one quadrant for each slice was destructively analyzed. Results from these tests showed an approximate 1.5% relative variation in uranium concentration from the high to the low point. Successive pieces showed less than 1% relative difference. The 1-in. pieces have been canned and shipped to LASL for testing and will be returned with the Californium Shuffler. The remaining 1/4-in. slices have been sent to NBL and LASL for destructive analysis
Californium-252: a remarkable versatile radioisotope

International Nuclear Information System (INIS)

Osborne-Lee, I.W.; Alexander, C.W.

1995-01-01

A product of the nuclear age, Californium-252 ( 252 Cf) has found many applications in medicine, scientific research, industry, and nuclear science education. Californium-252 is unique as a neutron source in that it provides a highly concentrated flux and extremely reliable neutron spectrum from a very small assembly. During the past 40 years, 252 Cf has been applied with great success to cancer therapy, neutron radiography of objects ranging from flowers to entire aircraft, startup sources for nuclear reactors, fission activation for quality analysis of all commercial nuclear fuel, and many other beneficial uses, some of which are now ready for further growth. Californium-252 is produced in the High Flux Isotope Reactor (HFIR) and processed in the Radiochemical Engineering Development Center (REDC), both of which are located at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The REDC/HFIR facility is virtually the sole supplier of 252 Cf in the western world and is the major supplier worldwide. Extensive exploitation of this product was made possible through the 252 Cf Market Evaluation Program, sponsored by the United States Department of Energy (DOE) [then the Atomic Energy Commission (AEC) and later the Energy Research and Development Administration (ERDA)]. This program included training series, demonstration centers, seminars, and a liberal loan policy for fabricated sources. The Market Evaluation Program was instituted, in part, to determine if large-quantity production capability was required at the Savannah River Laboratory (SRL). Because of the nature of the product and the means by which it is produced, 252 Cf can be produced only in government-owned facilities. It is evident at this time that the Oak Ridge research facility can meet present and projected near-term requirements. The production, shipment, and sales history of 252 Cf from ORNL is summarized herein
Californium-252: a remarkable versatile radioisotope

Energy Technology Data Exchange (ETDEWEB)

Osborne-Lee, I.W.; Alexander, C.W.

1995-10-10

A product of the nuclear age, Californium-252 ({sup 252}Cf) has found many applications in medicine, scientific research, industry, and nuclear science education. Californium-252 is unique as a neutron source in that it provides a highly concentrated flux and extremely reliable neutron spectrum from a very small assembly. During the past 40 years, {sup 252}Cf has been applied with great success to cancer therapy, neutron radiography of objects ranging from flowers to entire aircraft, startup sources for nuclear reactors, fission activation for quality analysis of all commercial nuclear fuel, and many other beneficial uses, some of which are now ready for further growth. Californium-252 is produced in the High Flux Isotope Reactor (HFIR) and processed in the Radiochemical Engineering Development Center (REDC), both of which are located at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The REDC/HFIR facility is virtually the sole supplier of {sup 252}Cf in the western world and is the major supplier worldwide. Extensive exploitation of this product was made possible through the {sup 252}Cf Market Evaluation Program, sponsored by the United States Department of Energy (DOE) [then the Atomic Energy Commission (AEC) and later the Energy Research and Development Administration (ERDA)]. This program included training series, demonstration centers, seminars, and a liberal loan policy for fabricated sources. The Market Evaluation Program was instituted, in part, to determine if large-quantity production capability was required at the Savannah River Laboratory (SRL). Because of the nature of the product and the means by which it is produced, {sup 252}Cf can be produced only in government-owned facilities. It is evident at this time that the Oak Ridge research facility can meet present and projected near-term requirements. The production, shipment, and sales history of {sup 252}Cf from ORNL is summarized herein.
Local Structure in Americium and Californium Hexa-cyanoferrates - Comparison with Their Lanthanide Analogues

International Nuclear Information System (INIS)

Dupouy, G.; Bonhoure, I.; Dumas, Th.; Moisy, Ph.; Petit, S.; Den Auwer, Ch.; Conradson, St.D.; Hennig, Ch.; Scheinost, A.C.; Le Naour, C.; Simoni, E.

2011-01-01

Metal hexa-cyanoferrates are well known molecular solids for a large variety of cations, although very little has been described for actinide adducts. Two new members of actinide(III) hexa-cyanoferrates were synthesized with the cations americium and californium. They were structurally characterized by infrared and X-ray absorption spectroscopy. Combined EXAFS data at the iron K edge and actinide L 3 edge provide evidence for a three-dimensional model for these two new compounds. Structural data in terms of bond lengths were compared to those reported for the parent lanthanide(III) compounds, neodymium and gadolinium hexa-cyanoferrates, respectively: the americium compound with (KNd(III)Fe(II)-Fe-III(CN) 6 .4H 2 O and the californium compound with (KGd(III)Fe(II)(CN) . 3.5H 2 O and (KGd(III)Fe(II)(CN) 6 .3H 2 O. This comparison between actinide and lanthanide homologues has been carried out on the basis of ionic radii considerations. The americium and neodymium environments appear to be very similar and are arranged in a tri-capped trigonal prism polyhedron of coordination number 9 (CN: 9), in which the americium atom is bonded to six nitrogen atoms and to three water molecules. For the californium adduct, a similar comparison and bond length and angle values derived from EXAFS studies suggest that the californium cation sits in a bi-capped trigonal prism (CN: 8) as in (KGd(III)Fe(II)(CN) 6 . 3H 2 O. This arrangement differs from that in the structure of (KGd(III)Fe(II)(CN) 6 .3.5H 2 O, in which the gadolinium atom is surrounded by 9 atoms. This is one of the rare pieces of information revealed by EXAFS spectroscopy for americium and californium in comparison to lanthanide atoms in molecular solid compounds. A discussion on the decrease in bond length and coordination number from americium to californium is also provided, on the basis of crystallographic results reported in the literature for actinide(III) and lanthanide(III) hydrate series. (authors)
Proposed Californium-252 User Facility for Neutron Science at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Martin, R.C.; Laxson, R.R.; Knauer, J.B.

1996-01-01

The Radiochemical Engineering Development Center (REDC) at ORNL has petitioned to establish a Californium-252 User Facility for Neutron Science for academic, industrial, and governmental researchers. The REDC Californium Facility (CF) stores the national inventory of sealed 252 Cf neutron source for university and research loans. Within the CF, the 252 Cf storage pool and two uncontaminated hot cells currently in service for the Californium Program will form the physical basis for the User Facility. Relevant applications include dosimetry and experiments for neutron tumor therapy; fast and thermal neutron activation analysis of materials; experimental configurations for prompt gamma neutron activation analysis; neutron shielding and material damage studies; and hardness testing of radiation detectors, cameras, and electronics. A formal User Facility simplifies working arrangements and agreements between US DOE facilities, academia, and commercial interests
Californium loan programme

International Nuclear Information System (INIS)

1974-01-01

The offer of the United States to loan Californium-252 sources to the IAEA was made by Dr. Glenn T. Seaborg, then chairman of the USAEC, in his opening statement at the 15th. General Conference of the IAEA held in Vienna in 1971. The purpose of this loan was to make neutron emitting sources available to universities in the Member States for use in educational programmes. The sources, in the form of small needles designed for medical use in radiation therapy, were judged highly suitable for didactic applications due to their small size, limited activity and well documented radiological parameters. Subsequently, in May 1973, the Director General announced the availability of the Californium sources to the Member States. To date, numerous sources have been loaned to universities in Czechoslovakia, Costa Rica, the Federal Republic of Germany, Ghana, India, Iran, Israel, Japan, South Africa, Switzerland, the United Kingdom and Uruguay; additional applications for loans are being processed. It is anticipated that the loan programme will be terminated in 1975 once all the available sources have been distributed. n order to provide guidance for the Member States on the safe exploitation of these sources, a prototype use and storage facility was designed by IAEA staff of the Dosimetry Section of the Division of Life Sciences, and constructed at the IAEA laboratory in Seibersdorf, Austria. Figures 2-5 illustrate some of the details of this container, which is being given to the Ghana Nuclear Centre in support of a training programme for students at the university in Accra. Further advice to users of these sources will be provided by the publication of an instructional syllabus, a laboratory manual for experiments and the safety precautions inherent in the proper handling of neutron emitting radionuclides, authored by Professors Erich J. Hall and Harald H. Rossi of Columbia University. The syllabus and manual will be published as part of the IAEA Technical Series in September
Production, Distribution, and Applications of Californium-252 Neutron Sources

International Nuclear Information System (INIS)

Balo, P.A.; Knauer, J.B.; Martin, R.C.

1999-01-01

The radioisotope 252 Cf is routinely encapsulated into compact, portable, intense neutron sources with a 2.6-year half-life. A source the size of a person's little finger can emit up to 10 11 neutrons/s. Californium-252 is used commercially as a reliable, cost-effective neutron source for prompt gamma neutron activation analysis (PGNAA) of coal, cement, and minerals, as well as for detection and identification of explosives, laud mines, and unexploded military ordnance. Other uses are neutron radiography, nuclear waste assays, reactor start-up sources, calibration standards, and cancer therapy. The inherent safety of source encapsulations is demonstrated by 30 years of experience and by U.S. Bureau of Mines tests of source survivability during explosions. The production and distribution center for the U. S Department of Energy (DOE) Californium Program is the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL). DOE sells 252 Cf to commercial reencapsulators domestically and internationally. Sealed 252 Cf sources are also available for loan to agencies and subcontractors of the U.S. government and to universities for educational, research, and medical applications. The REDC has established the Californium User Facility (CUF) for Neutron Science to make its large inventory of 252 Cf sources available to researchers for irradiations inside uncontaminated hot cells. Experiments at the CUF include a land mine detection system, neutron damage testing of solid-state detectors, irradiation of human cancer cells for boron neutron capture therapy experiments, and irradiation of rice to induce genetic mutations
Californium source transfer

International Nuclear Information System (INIS)

Wallace, C.R.

1995-01-01

In early 1995, the receipt of four sealed californium-252 sources from Oak Ridge National Lab was successfully accomplished by a team comprised of Radiological Engineering, Radiological Operations and Health Physics Instrumentation personnel. A procedure was developed and walked-down by the participants during a Dry Run Evolution. Several special tools were developed during the pre-planning phases of the project which reduced individual and job dose to minimal levels. These included a mobile lifting device for attachment of a transfer ball valve assembly to the undercarriage of the Cannonball Carrier, a transfer tube elbow to ensure proper angle of the source transfer tube, and several tools used during emergency response for remote retrieval and handling of an unshielded source. Lessons were learned in the areas of contamination control, emergency preparedness, and benefits of thorough pre-planning, effectiveness of locally creating and designing special tools to reduce worker dose, and methods of successfully accomplishing source receipt evolutions during extreme or inclement weather
Spectroscopic and redox properties of curium and californium ions in concentrated aqueous carbonate-bicarbonate media

International Nuclear Information System (INIS)

Hobart, D.E.; Varlashkin, P.G.; Samhoun, K.; Haire, R.G.; Peterson, J.R.

1983-01-01

Multimilligram quantities of trivalent curium-248 and californium-249 were investigated by absorption spectroscopy, cyclic voltammetry, and bulk solution electrolysis in concentrated aqueous carbonate-bicarbonate solution. Actinide concentrations between 10 -4 and 10 -2 M were studied in 2 M sodium carbonate and 5.5 M potassium carbonate solutions at pH values from 8 to 14. The solution absorption spectra of Cm(III) and Cf(III) in carbonate media are presented for the first time and compared to literature spectra of these species in noncomplexing aqueous solution. It was anticipated that carbonate complexation of the actinide ions could provide a sufficient negative shift in the formal potentials of the M(IV)/M(III) couples of Cm and Cf to permit the generation and stabilization of their tetravalent states in aqueous carbonate-bicarbonate medium. No conclusive evidence was found in the present work to indicate the existence of any higher oxidation states of curium or californium in carbonate solution. Some possible reasons for our inability to generate and detect oxidized species of curium and californium in this medium are discussed

Californium-252

International Nuclear Information System (INIS)

1975-01-01

This meeting constituted the third phase of a project initiated by the Dosimetry Section of the IAEA in 1973. The first step, early in 1973, consisted of the development of a programme for the loan of Cf-252 sources to the Member States in support of education, training and some limited research. To date, 14 institutions in 13 Member States have participated in this loan programme. In August last year, the Agency published an instructional syllabus and laboratory manual authored by Professors Eric J. Hall and Harald H. Rossi of Columbia University (Californium-252 in Teaching and Research, Technical Reports Series No. 159). The appearance of this publication, including guidance on the design and construction of a storage and use facility, was the second phase of this programme aimed at providing some support to potential users in the fields of radiation biology and dosimetry. The objective of the programme's third phase - the convening of an Educational Seminar - was to provide a forum to bring together participants in the Agency's loan programme and experts in various scientific fields. Specifically, the Seminar consisted of a series of expert presentations in spectrometry, activation and prompt gamma analyses, on-stream analysis, dosimetry, health physics, radiology and radiotherapy. (author)
X-ray-diffraction study of californium metal to 16 GPa

International Nuclear Information System (INIS)

Peterson, J.R.; Benedict, U.; Dufour, C.; Birkel, I.; Haire, R.G.

1983-01-01

The first series of measurements to determine the structural behavior of californium (Cf) metal under pressure has been carried out. The initial dhcp structure transformed sluggishly with increasing pressure to a fcc structure. A bulk modulus of 50(5) GPa was derived for dhcp Cf metal from the relative volume (V/V 0 ) data to 10 GPa
Study of the shielding for spontaneous fission sources of Californium-252

International Nuclear Information System (INIS)

Davila R, I.

1991-06-01

A shielding study is made to attenuate, until maximum permissible levels, the neutrons radiation and photons emitted by spontaneous fission coming from a source of Californium-252. The compound package by a database (Library DLC-23) and the ANISNW code is used, in it version for personal computer. (Author)
Convenient method of simultaneously analyzing aluminum and magnesium in pharmaceutical dosage forms using californium-252 thermal neutron activation

International Nuclear Information System (INIS)

Landolt, R.R.; Hem, S.L.

1983-01-01

A commercial antacid suspension containing aluminum hydroxide and magnesium hydroxide products was used as a model sample to study the use of a californium-252 thermal neutron activation as a method for quantifying aluminum content as well as for the simultaneous assay of aluminum and magnesium. A 3.5-micrograms californium-252 source was used for the activation, and the induced aluminum-28 and magnesium-27 activity was simultaneously measured by sodium iodide crystal gamma-ray spectrometry using dual single-channel analyzers and scalers. The antacid suspension was contained in a chamber designed with the unique capability of serving as the container for counting the induced radioactivity in addition to being the irradiation chamber itself. This pilot study demonstrated that use of more intense californium-252 sources, which are commonly available, would provide a method that is competitive with the ethylenediaminetetraacetic acid titration method in precision and in other aspects as well
48 CFR 53.303-DD-254 - Department of Defense DD Form 254, Contract Security Classification Specification.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Department of Defense DD Form 254, Contract Security Classification Specification. 53.303-DD-254 Section 53.303-DD-254 Federal... Illustrations of Forms 53.303-DD-254 Department of Defense DD Form 254, Contract Security Classification...
Atlantic Richfield Hanford Company californium multiplier/delayed neutron counter safety analysis

International Nuclear Information System (INIS)

Zimmer, W.H.

1976-08-01

The Californium Multiplier (CFX) is a subcritical assembly of uranium surrounding 252 Cf spontaneously fissioning neutron sources; its function is to multiply the neutron flux to a level useful for activation analysis. This document summarizes the safety analysis aspects of the CFX, DNC, pneumatic transfer system, and instrumentation and to detail all the aspects of the total facility as a starting point for the ARHCO Safety Analysis Review. Recognized hazards and steps already taken to neutralize them are itemized
Californium oxygen system for 1.50 < O/Cf < 1.72

International Nuclear Information System (INIS)

Turcotte, R.P.; Haire, R.G.

1975-01-01

The californium-oxygen system was studied as a function of temperature, oxygen pressure, and stoichiometry by manometric and x-ray diffraction methods. The results establish rhombohedral Cf 7 O 12 as the stable compound obtained by heating Cf 2 O 3 in air. The isobaric oxidation-reduction cycles Cf 2 O 3 → Cf 7 O 12 → Cf 2 O 3 , observed in constant rate of heating (cooling) experiments, occur with large hysteresis. A close parallel to other fluorite related lanthanide and actinide oxide systems is established. (auth)
Assessment of the neutron component in a neutron-gamma field of a californium-252 source

International Nuclear Information System (INIS)

Tetteh, G.K.

1978-12-01

Experiments have been performed to determine the percentages of the different components in the radiation field of californium-252 which has now some clinical applications. Using Rossi Chambers in conjunction with absorption investigations involving lead and aluminium thimbles, it is observed that the dose rates due to the different components are: neutrons 54%; gammas 30%; betas 16%
Dicty_cDB: VHK254 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available VH (Link to library) VHK254 (Link to dictyBase) - - - Contig-U16260-1 VHK254P (Link to Original site) VHK2...54F 616 VHK254Z 744 VHK254P 1340 - - Show VHK254 Library VH (Link to library) Clone ID VHK2...e URL http://dictycdb.biol.tsukuba.ac.jp/CSM/VH/VHK2-C/VHK254Q.Seq.d/ Representative seq. ID VHK2...54P (Link to Original site) Representative DNA sequence >VHK254 (VHK254Q) /CSM/VH/VHK2-C/VHK2...BJ446805 ) Dictyostelium discoideum cDNA clone:ddv63k21, 3' ... 1455 0.0 1 ( BJ446732 ) Dictyostelium discoi
Measurements of integral cross sections in the californium-252 fission neutron spectrum

International Nuclear Information System (INIS)

Alberts, W.G.; Guenther, E.; Matzke, M.; Rassl, G.

1977-01-01

In a low-scattering arrangement cross sections averaged over the californium-252 spontaneous fission neutron spectrum were measured. The reactions 27 Al(n,α) 46 Ti, 47 Ti, 48 Ti(n,p), 54 Fe, 56 Fe(n,p), 58 Ni(n,p), 64 Zn(n,p), 115 In(n,n') were studied in order to obtain a consistent set of threshold detectors used in fast neutron flux density measurements. Overall uncertainties between 2 and 2.5% could be achieved; corrections due to neutron scattering in source and samples are discussed
Instrumental neutron activation determination of gold in mineral raw materials using a californium neutron source

International Nuclear Information System (INIS)

Shilo, N.A.; Ippolitov, E.G.; Ivanenko, V.V.; Kustov, B.N.; Zheleznov, V.V.; Aristov, G.N.; Kovalenko, V.V.; Kondrat'ev, N.B.

1983-01-01

A facility using a californium neutron source and a method for the neutron activation analysis of gold were developed. The sensitivity of the determination is 0.1 g/t. The causes of random and systematic errors have been studied. It is concluded that in prospection and evaluation of gold ore deposists, the traditional test tube analysis for gold may be replaced with the developed method. (author)
7 CFR 254.1 - General purpose.

Science.gov (United States)

2010-01-01

... 7 Agriculture 4 2010-01-01 2010-01-01 false General purpose. 254.1 Section 254.1 Agriculture... GENERAL REGULATIONS AND POLICIES-FOOD DISTRIBUTION ADMINISTRATION OF THE FOOD DISTRIBUTION PROGRAM FOR INDIAN HOUSEHOLDS IN OKLAHOMA § 254.1 General purpose. This part sets the requirement under which...
20 CFR 632.254 - Program startup.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Program startup. 632.254 Section 632.254 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INDIAN AND NATIVE AMERICAN EMPLOYMENT AND TRAINING PROGRAMS Summer Youth Employment and Training Programs § 632.254 Program startup...
Neutron reflector design with Californium 252 neutron for Boron neutron chapter therapy facility using MCNP5 simulation method

International Nuclear Information System (INIS)

Muhammad Fakhrurreza; Kusminanto; Y Sardjono

2014-01-01

In this research has made a reflector design to provide beams of Neutron for BNCT with Californium-252 radioactive source. This collimator is useful to obtain optimum epithermal neutron flux with the smallest impurity radiation (thermal neutron, fast neutron, and gamma). The design process is done using Monte Carlo N-Particle simulation version 5 (MCNP5) code to calculate the neutron flux tally form. The chosen reflector design is the reflectors which use material such as BeO ceramic with 13 cm thick. Moderator use sulfur material with the slope angle of the cone is 30°. From the calculation result, it is obtained that Reflector with 1 gram Californium-252 source can produce a neutron output thermal which has thermal neutron specification 2.23189 x 10 9 n/s.cm 2 , epithermal neutron 3.51548 x 10 9 n/s.cm 2 , and fast neutron 4.82241 x 10 9 n/s.cm 2 From the result, it needs additional collimator because the BNCT requirement. (author)
Calibration of a Modified Californium Shuffler

International Nuclear Information System (INIS)

Sadowski, E.T.; Armstrong, F.; Oldham, R.; Ceo, R.; Williams, N.

1995-01-01

A californium shuffler originally designed to assay hollow cylindrical pieces of UA1 has been modified to assay solid cylinders. Calibration standards were characterized via chemical analysis of the molten UA1 taken during casting of the standards. The melt samples yielded much more reliable characterization data than drill samples taken from standards after the standards had solidified. By normalizing one well-characterized calibration curve to several standards at different enrichments, a relatively small number of standards was required to develop an enrichment-dependent calibration. The precision of this shuffler is 0.65%, and the typical random and systematic uncertainties are 0.53% and 0.73%, respectively, for a six minute assay of an ingot containing approximately 700 grams of 235 U. This paper will discuss (1) the discrepancies encountered when UA1 standards were characterized via melt samples versus drill samples, (2) a calibration methodology employing a small number of standards, and (3) a comparison of results from a previously unused shuffler with an existing shuffler. A small number of UA1 standards have been characterized using samples from the homogeneous molten state and have yielded enrichment-dependent and enrichment-independent calibration curves on two different shufflers
27 CFR 44.254 - Shipping containers.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Shipping containers. 44.254 Section 44.254 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Requirements § 44.254 Shipping containers. Each shipping case, crate, or other container, in which cigars are...
Prompt neutron spectrum of the spontaneous fission of californium-252

International Nuclear Information System (INIS)

Zamyatnin, Yu.S.; Kroshkin, N.I.; Korostylev, V.A.; Nefedov, V.N.; Ryazanov, D.K.; Starostov, B.I.; Semenov, A.F.

1976-01-01

The californium-252 spontaneous fission neutron spectrum was measured in the energy range of 0.01 to 10 MeV by the time-of-flight technique using various neutron detectors. The measurements of 252 Cf neutron spectrum at energies of 0.01 to 5 MeV were performed as a function of fission fragment kinetic energy. The mean neutron spectrum energy in the range of 0.7 to 10 MeV was found from the results of measurements. The irregularity in the 252 Cf neutron spectrum in the neutron energy range of less than 0.7 MeV compared to theoretical values is discussed. The mechanism of 252 Cf neutron emission is also discussed on the basis of neutron yield angle measurements. 12 references
Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory TRU Californium Shipping Container

International Nuclear Information System (INIS)

Box, W.D.; Shappert, L.B.; Seagren, R.D.; Klima, B.B.; Jurgensen, M.C.; Hammond, C.R.; Watson, C.D.

1980-01-01

An analytical evaluation of the Oak Ridge National Laboratory TRU Californium Shipping Container was made in order to demonstrate its compliance with the regulations governing off-site shipment of packages that contain radioactive material. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of this evaluation demonstrate that the container complies with the applicable regulations
Neutron emission in fission of highly excited californium nuclei (E*=76 MeV)

International Nuclear Information System (INIS)

Blinov, M.V.; Bordyug, V.M.; Kozulin, Eh.M.; Mozhaev, A.N.; Levitovich, M.; Muzychka, Yu.A.; Penionzhkevich, Yu.Eh.; Pustyl'nik, B.I.

1990-01-01

The differential cross sections for neutron production in the fission of highly excited californium nuclei formed in the 238 U+ 12 C (105 MeV) reaction have been measured. From the analysis of the experimental data is follows that the number of pre-fission neutrons substantially exceeds the value obtained in the framework of the standard statistical model. The saddle-to-scission time of the excited nucleus is estimated on the basis of the neutron multiplicity. The dependences of the neutron number and neutron average energies upon the fragment mass are determined
Neutron emission in fission of highly excited californium nuclei (E* = 76 MeV)

International Nuclear Information System (INIS)

Blinov, M.V.; Bordyug, V.M.; Kozulin, E.M.; Levitovich, M.; Mozhaev, A.N.; Muzychka, Yu.A.; Penionzhkevich, Yu.E.; Pustyl'nik, B.I.

1990-01-01

Differential cross sections for neutron production have been measured in fission of excited californium nuclei produced in the reaction 238 U + 12 C (105 MeV). It follows from analysis of the experimental results that the number of neutrons emitted before fission considerably exceeds the number obtained in the framework of the standard statistical model. On the basis of the multiplicity of neutrons they authors have estimated the time of fission of the excited nucleus. The dependence of the number of neutrons and their average energies on the mass of the fragments is determined

7 CFR 254.2 - Definitions.

Science.gov (United States)

2010-01-01

... 7 Agriculture 4 2010-01-01 2010-01-01 false Definitions. 254.2 Section 254.2 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE... (25 CFR part 81 et. seq.). (b) FNS service area means the areas over which FNS has approved the food...
A californium-252 source for radiobiological studies at Hiroshima University

International Nuclear Information System (INIS)

Kato, Kazuo; Takeoka, Seiji; Kuroda, Tokue; Tsujimura, Tomotaka; Kawami, Masaharu; Hoshi, Masaharu; Sawada, Shozo

1987-01-01

A 1.93 Ci (3.6 mg) californium-252 source was installed in the radiation facility of the Research Institute for Nuclear Medicine and Biology, Hiroshima University. This source produces fission neutrons (8.7 x 10 9 n/s at the time of its installation), which are similar to neutron spectrum of the atomic bombs. It is useful for studying biological effects of fission neutrons and neutron dosimetry. An apparatus was dosigned to accomodate this source and to apply it to such studies. It has resulted in profitable fission neutron exposures, while suppressing scattered neutrons and secondary gamma rays. This apparatus incorporates many safety systems, including one which interlocks with all of doors and an elevator serving the exposure room, so as to prevent accidents involving users. (author)
4 CFR 25.4 - Preservation of property.

Science.gov (United States)

2010-01-01

... 4 Accounts 1 2010-01-01 2010-01-01 false Preservation of property. 25.4 Section 25.4 Accounts GOVERNMENT ACCOUNTABILITY OFFICE GENERAL PROCEDURES CONDUCT IN THE GOVERNMENT ACCOUNTABILITY OFFICE BUILDING AND ON ITS GROUNDS § 25.4 Preservation of property. The improper disposal of rubbish in the GAO...
36 CFR 254.42 - Valuation of tracts.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Valuation of tracts. 254.42 Section 254.42 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP ADJUSTMENTS Conveyance of Small Tracts § 254.42 Valuation of tracts. (a) Approximately equal value shall be...
Californium production at the transuranium processing plant

International Nuclear Information System (INIS)

King, L.J.

1976-01-01

The Transuranium Processing Plant (TRU) at ORNL, which is the production, storage, and distribution center for the ERDA heavy element research program, is described. About 0.5 percent of 252 Cf is currently being produced. TRU is a hot-cell, chemical processing facility of advanced design. New concepts have been incorporated into the facility for absolute containment, remote operation, remote equipment installation, and remote maintenance. The facilities include a battery of nine heavily shielded process cells served by master-slave manipulators and eight laboratories, four on each of two floors. Processing includes chemical dissolution of the targets followed by a series of solvent extraction, ion exchange, and precipitation steps to separate and purify the transuranium elements. The transcurium elements Bk, Cf, Es, and Fm are distributed to users. Remote techniques are used to fabricate the Am and Cm into target rods for reirradiation in the HFIR. Californium-252 that is in excess of the needs of the heavy element research program and the Cf sales program is stored at TRU and processed repeatedly to recover the daughter product 248 Cm, which is a highly desirable research material
Comparison of the Savannah River Site billet active well coincidence counter and two Californium Shufflers

International Nuclear Information System (INIS)

Sadowski, E.T.; Griffin, J.C.; Rinard, P.M.

1991-01-01

A Scrap Californium Shuffler at the Savannah River Site (SRS) was calibrated to assay the U-Al cores of billets (an intermediate step in the SRS reactor fuel fabrication cycle.) The precision of the Scrap Shuffler over several years has been approximately 0.50%. A typical total uncertainty for the assay of a core on the Scrap Shuffler is approximately 0.33% for a twelve minute assay. The precision over several months and a typical total uncertainty for the Billet Active Well (neutron) Coincidence Counter (BAWCC) are approximately 1.0% and 1.9%, respectively, for a fifteen minute assay. A new Billet Californium Shuffler specifically designed for assaying SRS billets has yielded precision (over one month) and total uncertainty results of 0.40% and 0.69%, respectively, for an eight minute assay. The introduction of a measurement point into the fuel fabrication cycle to replace estimates based upon material weight will greatly enhance material and process control in the Reactor Materials area of SRS. The use of all three instruments provides a comparison of the relative merits of Active Well (neutron) Coincidence Counters (AWCCs) and shufflers for assay of homogeneous and geometrically simple material containing 235 U. The measurement precisions, systematic and random uncertainties, as well as the procurement and operation of each instrument will be compared. 3 refs., 5 figs., 1 tab
Measurement of californium-252 gamma photons depth dose distribution in tissue equivalent material. Vol. 4

Energy Technology Data Exchange (ETDEWEB)

Fadel, M A; El-Fiki, M A; Eissa, H M; Abdel-Hafez, A; Naguib, S H [National Institute of Standards, Cairo (Egypt)

1996-03-01

Phantom of tissue equivalent material with and without bone was used measuring depth dose distribution of gamma-rays from californium-252 source. The source was positioned at center of perspex walled phantom. Depth dose measurements were recorded for X, Y and Z planes at different distances from source. TLD 700 was used for measuring the dose distribution. Results indicate that implantation of bone in tissue equivalent medium cause changes in the gamma depth dose distribution which varies according to variation in bone geometry. 9 figs.
Hypoxic versus normoxic external-beam irradiation of cervical carcinoma combined with californium-252 neutron brachytherapy. Comparative treatment results of a 5-year randomized study

Czech Academy of Sciences Publication Activity Database

Tačev, T.; Vacek, Antonín; Ptáčková, B.; Strnad, V.

2005-01-01

Roč. 181, č. 5 (2005), s. 273-284 ISSN 0179-7158 Institutional research plan: CEZ:AV0Z50040507 Keywords : cervical carcinoma * hypoxyradiotherapy * californium-252 Subject RIV: BO - Biophysics Impact factor: 3.490, year: 2005
Ab initio full-potential study of mechanical properties and magnetic phase stability of californium monopnictides (CfN and CfP)

Energy Technology Data Exchange (ETDEWEB)

Amari, S., E-mail: siham_amari@yahoo.fr [Faculté des Sciences de la Nature et de la Vie, Université Hassiba Benbouali, Chlef, 02000 (Algeria); Bouhafs, B. [Laboratoire de Modélisation et Simulation en Sciences des Matériaux, Université Djillali Liabès de Sidi Bel-Abbés, Sidi Bel-Abbés, 22000 (Algeria)

2016-09-15

Based on the first-principles methods, the structural, elastic, electronic, properties and magnetic ordering of californium monopnictides CfX (X = P) have been studied using the full-potential augmented plane wave plus local orbitals (FP-L/APW + lo) method within the framework of density functional theory (DFT). The electronic exchange correlation energy is described by generalized gradient approximation GGA and GGA+U (U is the Hubbard correction). The GGA+U method is applied to the rare-earth 5f states. We have calculated the lattice parameters, bulk modulii and the first pressure derivatives of the bulk modulii. The elastic properties of the studied compounds are only investigated in the most stable calculated phase. In order to gain further information, we have calculated Young’s modulus, shear modulus, anisotropy factor and Kleinman parameter by the aid of the calculated elastic constants. The results mainly show that californium monopnictides CfX (X = P) have an antiferromagnetic spin ordering. Density of states (DOS) and charge densities for both compounds are also computed in the NaCl (B1) structure.
36 CFR 254.10 - Bargaining; arbitration.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Bargaining; arbitration. 254.10 Section 254.10 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE... determine values. Bargaining or any other process must be based on an objective analysis of the valuation in...
29 CFR 1910.254 - Arc welding and cutting.

Science.gov (United States)

2010-07-01

... 29 Labor 5 2010-07-01 2010-07-01 false Arc welding and cutting. 1910.254 Section 1910.254 Labor... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Welding, Cutting and Brazing § 1910.254 Arc welding and cutting. (a... following limits shall not be exceeded: (i) Alternating-current machines (A) Manual arc welding and cutting...
36 CFR 254.6 - Segregative effect.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Segregative effect. 254.6... ADJUSTMENTS Land Exchanges § 254.6 Segregative effect. (a) If a proposal is made to exchange Federal lands... segregative effect terminates as follows: (1) Automatically, upon issuance of a patent or other document of...
7 CFR 254.4 - Application by an ITO.

Science.gov (United States)

2010-01-01

... 7 Agriculture 4 2010-01-01 2010-01-01 false Application by an ITO. 254.4 Section 254.4 Agriculture... INDIAN HOUSEHOLDS IN OKLAHOMA § 254.4 Application by an ITO. (a) Application to FNS Regional Office. An ITO which desires to participate in the Food Distribution Program shall file an application with the...
7 CFR 254.3 - Administration by an ITO.

Science.gov (United States)

2010-01-01

... 7 Agriculture 4 2010-01-01 2010-01-01 false Administration by an ITO. 254.3 Section 254.3... FOR INDIAN HOUSEHOLDS IN OKLAHOMA § 254.3 Administration by an ITO. (a) Applicability of part 253. All... any claim and to settle and adjust any claim against an ITO. (d) ITO administration. The ITO, acting...
Study of the shielding for spontaneous fission sources of Californium-252; Estudio de blindaje para fuentes de fision espontanea de Californio-252

Energy Technology Data Exchange (ETDEWEB)

Davila R, I

1991-06-15

A shielding study is made to attenuate, until maximum permissible levels, the neutrons radiation and photons emitted by spontaneous fission coming from a source of Californium-252. The compound package by a database (Library DLC-23) and the ANISNW code is used, in it version for personal computer. (Author)
Possible stabilization of the tetravalent oxidation state of berkelium and californium in acetonitrile with triphenylarsine oxide

International Nuclear Information System (INIS)

Payne, G.F.; Peterson, J.R.

1987-01-01

It appears that we may have prepared Bk(IV) nitrate.nTPAs0 and Bk(IV) perchlorate.nTPAs0 complexes which formed the corresponding Cf(IV) complexes through the beta decay of Bk-249. Definitive proof should come from similar experiments with quantities of Bk-249 large enough to allow spectrophotometric detection of the characteristic f→f transitions in these berkelium and californium species. It is clear, however, that TPAs0 and acetonitrile can play a pivotal role in the stabilization of lanact(IV) species
Experimental studies on californium bioavailability to marine benthic invertebrates

International Nuclear Information System (INIS)

Fowler, S.W.; Carvalho, F.P.; Aston, S.R.

1986-01-01

252 Cf is readily taken up by benthic invertebrates from sea water, reaching whole-body concentration factors of 763 in the polychaete Hermione hystrix, 220 in the shrimp Lysmata seticaudata, 665 in the crab Pilumnus hirtellus and 78 in the bivalve mollusc Venerupis decussata after 3 weeks exposure. Surface sorption plays a predominant role in the uptake process. Depuration in clean sea water was a relatively slow process. The shrimp Lysmata eliminated 252 Cf very rapidly due to moulting. Absorption coefficients for ingested 252 Cf were high, approx. 23% in crabs and approx. 97% in brittlestars. The absorbed fraction was excreted twice as fast from crabs as brittlestars. Exposure of organisms to labelled sediment resulted in low transfer factors that were species dependent. There is some evidence to suggest that uptake from sediments is primarily due to 252 Cf transfer from the pore water. Comparison of these results with published experimental data on other transuranic nuclides in the same or similar species suggests that californium bioavailability is roughly equivalent to that of plutonium and americium. (author)
36 CFR 254.11 - Exchanges at approximately equal value.

Science.gov (United States)

2010-07-01

... equal value. 254.11 Section 254.11 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP ADJUSTMENTS Land Exchanges § 254.11 Exchanges at approximately equal value. (a) The authorized officer may exchange lands which are of approximately equal value upon a determination that: (1...
36 CFR 254.4 - Agreement to initiate an exchange.

Science.gov (United States)

2010-07-01

... exchange. 254.4 Section 254.4 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP ADJUSTMENTS Land Exchanges § 254.4 Agreement to initiate an exchange. (a) Exchanges may be proposed by the Forest Service or by any person, State, or local government. Initial exchange proposals...
40 CFR 52.254 - Organic solvent usage.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Organic solvent usage. 52.254 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.254 Organic solvent usage. (a) This... (d) of this section and the architectural coatings and solvent disposal emission limitations...

36 CFR 254.34 - Mineral survey fractions.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Mineral survey fractions. 254... LANDOWNERSHIP ADJUSTMENTS Conveyance of Small Tracts § 254.34 Mineral survey fractions. (a) Mineral survey fractions subject to conveyance under this subpart are limited to those tracts which: (1) Cannot be...
30 CFR 254.41 - Training your response personnel.

Science.gov (United States)

2010-07-01

... procedures; (3) Oil-spill trajectory analysis and predicting spill movement; and (4) Any other... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Training your response personnel. 254.41 Section 254.41 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL...
Californium-252 Brachytherapy Combined With External-Beam Radiotherapy for Cervical Cancer: Long-Term Treatment Results

International Nuclear Information System (INIS)

Lei Xin; Qian Chengyuan; Qing Yi; Zhao Kewei; Yang Zhengzhou; Dai Nan; Zhong Zhaoyang; Tang Cheng; Li Zheng; Gu Xianqing; Zhou Qian; Feng Yan; Xiong Yanli; Shan Jinlu; Wang Dong

2011-01-01

Purpose: To observe, by retrospective analysis, the curative effects and complications due to californium-252 ( 252 Cf) neutron intracavitary brachytherapy (ICBT) combined with external-beam radiotherapy (EBRT) in the treatment of cervical cancer. Methods and Materials: From February 1999 to December 2007, 696 patients with cervical cancer (Stages IB to IIIB) were treated with 252 Cf-ICBT in combination of EBRT. Of all, 31 patients were at Stage IB, 104 at IIA, 363 at IIB, 64 at IIIA, and 134 at IIIB. Californium-252 ICBT was delivered at 7–12 Gy per insertion per week, with a total dose of 29–45 Gy to reference point A in three to five insertions. The whole pelvic cavity was treated with 8-MV X-ray external irradiation at 2 Gy per fraction, four times per week. After 16–38 Gy of external irradiation, the center of the whole pelvic field was blocked with a 4-cm-wide lead shield, with a total external irradiation dose of 44–56 Gy. The total treatment course was 5 to 6 weeks. Results: Overall survival rate at 3 and 5 years for all patients was 76.0% and 64.9%, respectively. Disease-free 3- and 5-year survival rates of patients were 71.2% and 58.4%, respectively. Late complications included vaginal contracture and adhesion, radiation proctitis, radiation cystitis, and inflammatory bowel, which accounted for 5.8%, 7.1%, 6.2%, and 4.9%, respectively. Univariate analysis results showed significant correlation of stage, age, histopathologic grade, and lymph node status with overall survival. Cox multiple regression analysis showed that the independent variables were stage, histopathologic grade, tumor size, and lymphatic metastasis in all patients. Conclusion: Results of this series suggest that the combined use of 252 Cf-ICBT with EBRT is an effective method for treatment of cervical cancer.
Teratogenic effect of Californium-252 irradiation in rats

International Nuclear Information System (INIS)

Satow, Yukio; Lee, Juing-Yi; Hori, Hiroshi; Okuda, Hiroe; Tsuchimoto, Shigeo; Sawada, Shozo; Yokoro, Kenjiro

1989-01-01

The teratogenicity of Californium-252 (Cf-252) irradiation which generates approximately 70% 2.3 MeV fast neutron and 30% gamma rays was evaluated. A single whole body exposure of Cf-252 at various doses was given to pregnant rats on day 8 or 9 of pregnancy, followed by microscopic autopsy of the fetuses at the terminal stage of pregnancy to search for external and internal malformations. For comparison, pregnant rats were irradiated with various doses of Cobalt-60 (Co-60) standard gamma rays at the same dose rate (1 rad/min.). The doses were 20-120 rad of Cf-252 and 80-220 rad of Co-60. Using frequency of radiation induced malformations observed on day 8 of pregnancy as an index, relative biological effectiveness (RBE) of 2.3-2.7 was obtained from the straight line obtained by modifying by the least squares method the frequency curves of malformed fetuses in total implants and in surviving fetuses. The types of malformations induced by Cf-252 and Co-60 irradiation were alike. Using fetal LD 50 as an index, 2.4 was obtained as RBE when irradiated on day 8 of pregnancy and 3.1 as that when irradiated on day 9. The results showed that Cf-252 had stronger a teratogenic effect than Co-60 gamma rays. (author)
47 CFR 1.254 - Nature of the hearing; burden of proof.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Nature of the hearing; burden of proof. 1.254 Section 1.254 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Hearing Proceedings Hearing and Intermediate Decision § 1.254 Nature of the hearing; burden of proof. Any hearing upon...
Transport calculations of. gamma. -ray flux density and dose rate about implantable californium-252 sources

Energy Technology Data Exchange (ETDEWEB)

Shapiro, A; Lin, B I [Cincinnati Univ., Ohio (USA). Dept. of Chemical and Nuclear Engineering; Windham, J P; Kereiakes, J G

1976-07-01

..gamma.. flux density and dose rate distributions have been calculated about implantable californium-252 sources for an infinite tissue medium. Point source flux densities as a function of energy and position were obtained from a discrete-ordinates calculation, and the flux densities were multiplied by their corresponding kerma factors and added to obtain point source dose rates. The point dose rates were integrated over the line source to obtain line dose rates. Container attenuation was accounted for by evaluating the point dose rate as a function of platinum thickness. Both primary and secondary flux densities and dose rates are presented. The agreement with an independent Monte Carlo calculation was excellent. The data presented should be useful for the design of new source configurations.
Beyond Californium-A Neutron Generator Alternative for Dosimetry and Instrument Calibration in the U.S.

Science.gov (United States)

Piper, Roman K; Mozhayev, Andrey V; Murphy, Mark K; Thompson, Alan K

2017-09-01

Evaluations of neutron survey instruments, area monitors, and personal dosimeters rely on reference neutron radiations, which have evolved from the heavy reliance on (α,n) sources to a shared reliance on (α,n) and the spontaneous fission neutrons of californium-252 (Cf). Capable of producing high dose equivalent rates from an almost point source geometry, the characteristics of Cf are generally more favorable when compared to the use of (α,n) and (γ,n) sources or reactor-produced reference neutron radiations. Californium-252 is typically used in two standardized configurations: unmoderated, to yield a fission energy spectrum; or with the capsule placed within a heavy-water moderating sphere to produce a softened spectrum that is generally considered more appropriate for evaluating devices used in nuclear power plant work environments. The U.S. Department of Energy Cf Loan/Lease Program, a longtime origin of affordable Cf sources for research, testing and calibration, was terminated in 2009. Since then, high-activity sources have become increasingly cost-prohibitive for laboratories that formerly benefited from that program. Neutron generators, based on the D-T and D-D fusion reactions, have become economically competitive with Cf and are recognized internationally as important calibration and test standards. Researchers from the National Institute of Standards and Technology and the Pacific Northwest National Laboratory are jointly considering the practicality and technical challenges of implementing neutron generators as calibration standards in the U.S. This article reviews the characteristics of isotope-based neutron sources, possible isotope alternatives to Cf, and the rationale behind the increasing favor of electronically generated neutron options. The evaluation of a D-T system at PNNL has revealed characteristics that must be considered in adapting generators to the task of calibration and testing where accurate determination of a dosimetric quantity is
Neutron activation analysis at the Californium User Facility for Neutron Science

International Nuclear Information System (INIS)

Martin, R.C.; Smith, E.H.; Glasgow, D.C.; Jerde, E.A.; Marsh, D.L.; Zhao, L.

1997-12-01

The Californium User Facility (CUF) for Neutron Science has been established to provide 252 Cf-based neutron irradiation services and research capabilities including neutron activation analysis (NAA). A major advantage of the CUF is its accessibility and controlled experimental conditions compared with those of a reactor environment The CUF maintains the world's largest inventory of compact 252 Cf neutron sources. Neutron source intensities of ≤ 10 11 neutrons/s are available for irradiations within a contamination-free hot cell, capable of providing thermal and fast neutron fluxes exceeding 10 8 cm -2 s -1 at the sample. Total flux of ≥10 9 cm -2 s -1 is feasible for large-volume irradiation rabbits within the 252 Cf storage pool. Neutron and gamma transport calculations have been performed using the Monte Carlo transport code MCNP to estimate irradiation fluxes available for sample activation within the hot cell and storage pool and to design and optimize a prompt gamma NAA (PGNAA) configuration for large sample volumes. Confirmatory NAA irradiations have been performed within the pool. Gamma spectroscopy capabilities including PGNAA are being established within the CUF for sample analysis
50 CFR 216.254 - Mitigation.

Science.gov (United States)

2010-10-01

..., DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Taking Marine Mammals Incidental to Conducting Precision Strike Weapon Missions in the Gulf of Mexico § 216.254... greatest extent practicable, adverse impacts on marine mammal species and stocks and their habitats. When...
Application of californium-252 neutron sources for analytical chemistry

International Nuclear Information System (INIS)

Ishii, Daido

1976-01-01

The researches made for the application of Cf-252 neutron sources to analytical chemistry during the period from 1970 to 1974 including partly 1975 are reviewed. The first part is the introduction to the above. The second part deals with general review of symposia, publications and the like. Attention is directed to ERDA publishing the periodical ''Californium-252 Progress'' and to a study group of Cf-252 utilization held by Japanese Radioisotope Association in 1974. The third part deals with its application for radio activation analysis. The automated absolute activation analysis (AAAA) of Savannha River is briefly explained. The joint experiment of Savannha River operation office with New Brunswick laboratory is mentioned. Cf-252 radiation source was used for the non-destructive analysis of elements in river water. East neutrons of Cf-252 were used for the quantitative analysis of lead in paints. Many applications for industrial control processes have been reported. Attention is drawn to the application of Cf-252 neutron sources for the field search of neutral resources. For example, a logging sonde for searching uranium resources was developed. the fourth part deals with the application of the analysis with gamma ray by capturing neutrons. For example, a bore hole sonde and the process control analysis of sulfur in fuel utilized capture gamma ray. The prompt gamma ray by capturing neutrons may be used for the nondestructive analysis of enrivonment. (Iwakiri, K.)
Spectral investigation of neutron radiation in three-sectional concrete labyrinth from a californium-252 source

International Nuclear Information System (INIS)

Belogorlov, E.A.; Britvich, G.I.; Getmanov, V.B.

1985-01-01

Construction of labyrinths in points of communication output from the storage-ring under construction is accompanied by numerous difficulties due to a considerable number of gas and cryogenic pipelines, which require large cross sections at the minimal length of the pipelines proper for their location. It results in unfavourable for radiation attenuation ratios between cross section and length of the labyrinth separate sections. Neutron spectra in a model concrete labyrinth, at the entrance to which a neutron source with fission spectrum (californium-252) and the same source in a polyethylene moderator are located, are measured. On the basis of the spectra obtained the formation of fluence and equivalent dose along the labyrinth geometric axis is analyzed. Conditions permitting actually to reduce radiation dose in the labyrinth (dead end provision, the use of cover materials, construction of diaphragms and shielding plates) are simulated
Susceptibility to Stress Corrosion Cracking of 254SMO SS

Directory of Open Access Journals (Sweden)

De Micheli Lorenzo

2002-01-01

Full Text Available The susceptibility to stress corrosion cracking (SCC of solubilized and sensitized 254SMO SS was studied in sodium chloride, and sodium fluoride solutions at 80 °C and sulfuric acid solutions in presence of sodium chloride at 25 °C. The influence of salt concentration, pH values and the addition of thiosulfate was examined. The susceptibility to SCC was evaluated by Slow Strain Rate Tests (SSRT, at 1.5 x 10-6 s-1 strain rate. The behavior of 254SMO was compared to those of AISI 316L SS and Hastelloy C276. 254SMO showed an excellent resistance to SCC in all conditions, except in the more acidic solutions (pH <= 1 where, in the sensitized conditions, intergranular stress corrosion cracking occurred.
Comparative functional analysis of two fibroblast growth factor receptor 1 (FGFR1) mutations affecting the same residue (R254W and R254Q) in isolated hypogonadotropic hypogonadism (IHH).

Science.gov (United States)

Koika, Vasiliki; Varnavas, Petros; Valavani, Helen; Sidis, Yisrael; Plummer, Lacey; Dwyer, Andrew; Quinton, Richard; Kanaka-Gantenbein, Christine; Pitteloud, Nelly; Sertedaki, Amalia; Dacou-Voutetakis, Catherine; Georgopoulos, Neoklis A

2013-03-01

FGFR1 mutations have been identified in both Kallmann syndrome and normosmic HH (nIHH). To date, few mutations in the FGFR1 gene have been structurally or functionally characterized in vitro to identify molecular mechanisms that contribute to the disease pathogenesis. We attempted to define the in vitro functionality of two FGFR1 mutants (R254W and R254Q), resulting from two different amino acid substitutions of the same residue, and to correlate the in vitro findings to the patient phenotypes. Two unrelated GnRH deficient probands were found to harbor mutations in FGFR1 (R254W and R254Q). Mutant signaling activity and expression levels were evaluated in vitro and compared to a wild type (WT) receptor. Signaling activity was determined by a FGF2/FGFR1 dependent transcription reporter assay. Receptor total expression levels were assessed by Western blot and cell surface expression was measured by a radiolabeled antibody binding assay. The R254W maximal receptor signaling capacity was reduced by 45% (p<0.01) while R254Q activity was not different from WT. However, both mutants displayed diminished total protein expression levels (40 and 30% reduction relative to WT, respectively), while protein maturation was unaffected. Accordingly, cell surface expression levels of the mutant receptors were also significantly reduced (35% p<0.01 and 15% p<0.05, respectively). The p.R254W and p.R254Q are both loss-of-function mutations as demonstrated by their reduced overall and cell surface expression levels suggesting a deleterious effect on receptor folding and stability. It appears that a tryptophan substitution at R254 is more disruptive to receptor structure than the more conserved glutamine substitution. No clear correlation between the severity of in vitro loss-of-function and phenotypic presentation could be assigned. Copyright © 2012 Elsevier B.V. All rights reserved.
37 CFR 2.54 - Requirements for drawings submitted on paper.

Science.gov (United States)

2010-07-01

... submitted on paper. 2.54 Section 2.54 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK... drawings submitted on paper. The drawing must meet the requirements of § 2.52. In addition, in a paper submission, the drawing should: (a) Be on non-shiny white paper that is separate from the application; (b) Be...
cdc-25.4, a Caenorhabditis elegans Ortholog of cdc25, Is Required for Male Mating Behavior

Directory of Open Access Journals (Sweden)

Sangmi Oh

2016-12-01

Full Text Available Cell division cycle 25 (cdc25 is an evolutionarily conserved phosphatase that promotes cell cycle progression. Among the four cdc25 orthologs in Caenorhabditis elegans, we found that cdc-25.4 mutant males failed to produce outcrossed progeny. This was not caused by defects in sperm development, but by defects in male mating behavior. The cdc-25.4 mutant males showed various defects during male mating, including contact response, backing, turning, and vulva location. Aberrant turning behavior was the most prominent defect in the cdc-25.4 mutant males. We also found that cdc-25.4 is expressed in many neuronal cells throughout development. The turning defect in cdc-25.4 mutant males was recovered by cdc-25.4 transgenic expression in neuronal cells, suggesting that cdc-25.4 functions in neurons for male mating. However, the neuronal morphology of cdc-25.4 mutant males appeared to be normal, as examined with several neuronal markers. Also, RNAi depletion of wee-1.3, a C. elegans ortholog of Wee1/Myt1 kinase, failed to suppress the mating defects of cdc-25.4 mutant males. These findings suggest that, for successful male mating, cdc-25.4 does not target cell cycles that are required for neuronal differentiation and development. Rather, cdc-25.4 likely regulates noncanonical substrates in neuronal cells.
Use of polyethylene pellets in the design and construction of a storage safe, a transport vessel and a portable shield for californium-252

International Nuclear Information System (INIS)

Sharma, S.

1986-01-01

A storage and shielding facility for 300 μg of Californium-252 sources was designed and constructed. Though the safe was in a permanent location, the fact that it consisted of a lead bucket surrounded by polyethylene pellets made it simple, movable and inexpensive. If need be, more quantities of Cf-252 could be added without altering the basic design and sacrificing the radiation protection guidelines. The measured radiation levels from 300 μg of stored Cf-252 in and around the storage vault were lower than the expected dose rates by a factor of 5. The measured radiation levels around the occupied environs of the facility were below the maximum permissible yearly dose of 500mrem for non-occupational workers. A transport vessel was designed and constructed to carry up to 50 μg of Californium-252 sources. It consisted of a standard 55 gallon steel drum on casters containing cylindrical lead shield surrounded by polyethylene pellets. The measured maximum surface dose rates on the drum and at one meter away were within the radiation protection guidelines and were less than the expected dose rates. A portable shield was designed and constructed to protect the body in afterloading operations and handling of the sources. It consisted of polyethylene pellets in an aluminum box and an attached 10 cm thick plexiglass eye shield. The simple design, with the ease of using polyethylene pellets can be extended to construct bedside shields
High transfer cross sections from reactions with 254Es

International Nuclear Information System (INIS)

Schaedel, M.; Bruechle, W.; Bruegger, M.; Gaeggeler, H.; Moody, J.; Schardt, D.; Suemmerer, K.; Hulet, E.K.; Dougan, A.D.; Dougan, R.J.; Landrum, J.H.; Lougheed, R.W.; Wild, J.F.; O'Kelly, G.D.

1985-08-01

We report radiochemically determined cross sections for the heaviest known actinides produced in transfer reactions of 101 MeV 16 O, 98 MeV 18 O and 127 MeV 22 Ne with 254 Es as a target. A comparison with data for similar transfers from 248 Cm targets is made. Transfer cross sections are extrapolated for the production of unknown, neutron-rich isotopes of elements 101 through 105, and the unique potential of 254 Es as a target to make these exotic nuclei accessible is demonstrated. (orig.)
36 CFR 254.15 - Title standards.

Science.gov (United States)

2010-07-01

...) Conveyances of lands from the United States are made by patent, quitclaim deed, or deed and without express or implied warranties, except as to hazardous substances pursuant to § 254.3 of this subpart. (c) Title... of the existing use(s) authorized under the terms of the grant, permit, easement, or lease. The non...
Structure and formation mechanism of the transfermium isotope 254No

International Nuclear Information System (INIS)

Reiter, P.

1998-01-01

The ground-state band of the Z=102 isotope 254 No has been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadruple deformation, β = 0.27, is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of 254 No up to spin 14 means that its fission barrier persists at least up to that spin
17 CFR 230.254 - Solicitation of interest document for use prior to an offering statement.

Science.gov (United States)

2010-04-01

... subject to the antifraud provisions of the federal securities laws. No solicitation or acceptance of money... document for use prior to an offering statement. 230.254 Section 230.254 Commodity and Securities Exchanges...-Conditional Small Issues Exemption § 230.254 Solicitation of interest document for use prior to an offering...

Extraction of Trivalent Actinides and Lanthanides from Californium Campaign Rework Solution Using TODGA-based Solvent Extraction System

Energy Technology Data Exchange (ETDEWEB)

Benker, Dennis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Delmau, Laetitia Helene [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dryman, Joshua Cory [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-07-01

This report presents the studies carried out to demonstrate the possibility of quantitatively extracting trivalent actinides and lanthanides from highly acidic solutions using a neutral ligand-based solvent extraction system. These studies stemmed from the perceived advantage of such systems over cationexchange- based solvent extraction systems that require an extensive feed adjustment to make a low-acid feed. The targeted feed solutions are highly acidic aqueous phases obtained after the dissolution of curium targets during a californium (Cf) campaign. Results obtained with actual Cf campaign solutions, but highly diluted to be manageable in a glove box, are presented, followed by results of tests run in the hot cells with Cf campaign rework solutions. It was demonstrated that a solvent extraction system based on the tetraoctyl diglycolamide molecule is capable of quantitatively extracting trivalent actinides from highly acidic solutions. This system was validated using actual feeds from a Cf campaign.
Neutron activation analysis of the calcium content in vivo, using a 50μg source of californium 252

International Nuclear Information System (INIS)

Guey, A.; Zech, P.Y.; Meary, M.F.; Leitienne, P.

1975-01-01

Owing to the recent commercialisation of californium 252 it is now possible to obtain neutron fluxes strong enough for precise activation of the calcium content of biological targets. After the preliminary measurements necessary to establish the most suitable conditions for irradiating 3 to 5cm thick targets, two parallel sets of experiments were developed. In the first the medium-term total calcium variation was studied in 20 rats, 16 suffering from chronic kidney deficiency. In the second the precision expected as a function of the calcium content of the irradiated target was examined, using 3 sets of tissue equivalent standards of calcium contents 5, 20 and 50g respectively. The first results obtained on calcium 49 in vivo show that a calcium content variation can be followed with a sensitivity threshold below that obtained by conventional methods [fr
Identification of intermediates, acute toxicity removal, and kinetics investigation to the Ametryn treatment by direct photolysis (UV254), UV254/H2O2, Fenton, and photo-Fenton processes.

Science.gov (United States)

de Oliveira, Dirce Martins; Cavalcante, Rodrigo Pereira; da Silva, Lucas de Melo; Sans, Carme; Esplugas, Santiago; de Oliveira, Silvio Cesar; Junior, Amilcar Machulek

2018-02-09

This paper reports the degradation of 10 mg L -1 Ametryn solution with different advanced oxidation processes and by ultraviolet (UV 254 ) irradiation alone with the main objective of reducing acute toxicity and increase biodegradability. The investigated factors included Fe 2+ and H 2 O 2 concentrations. The effectiveness of the UV 254 and UV 254 /H 2 O 2 processes were investigated using a low-pressure mercury UV lamp (254 nm). Photo-Fenton process was explored using a blacklight blue lamp (BLB, λ = 365 nm). The UV 254 irradiation process achieved complete degradation of Ametryn solution after 60 min. The degradation time of Ametryn was greatly improved by the addition of H 2 O 2 . It is worth pointing out that a high rate of Ametryn removal was attained even at low concentrations of H 2 O 2 . The kinetic constant of the reaction between Ametryn and HO ● for UV 254 /H 2 O 2 was 3.53 × 10 8 L mol -1 s -1 . The complete Ametryn degradation by the Fenton and photo-Fenton processes was observed following 10 min of reaction for various combinations of Fe 2+ and H 2 O 2 under investigation. Working with the highest concentration (150 mg L -1 H 2 O 2 and 10 mg L -1 Fe 2+ ), around 30 and 70% of TOC removal were reached within 120 min of treatment by Fenton and photo-Fenton processes, respectively. Although it did not obtain complete mineralization, the intermediates formed in the degradation processes were hydroxylated and did not promote acute toxicity of Vibrio fischeri. Furthermore, a substantial improvement of biodegradability was obtained for all studied processes.
24 CFR 221.254 - Mortgage insurance premiums.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Mortgage insurance premiums. 221... Cost Homes § 221.254 Mortgage insurance premiums. (a) All of the provisions of §§ 203.260 through 203.295 of this chapter relating to mortgage insurance premiums shall apply to mortgages insured under...
Use of californium-252 neutron irradiator for in-vivo analysis of the bone calcium content of the hand

International Nuclear Information System (INIS)

Guey, A.; Leitienne, P.; Zech, P.Y.; Traeger, J.; Doyen, J.B.; Breton, J.P.

1979-01-01

With californium-252 it is easy to obtain a high neutron flux of the order of 10 9 n/s. The mean energy of this radiation, which is close on 2 MeV, activates calcium very well. The authors describe a storage and irradiator unit with a 100 μg californium source, with which it will henceforth be possible to develop this technique of measuring the calcium of the hand in a hospital. The test programme has three distinct phases: (1) irradiation of the biological target for 10 min; (2) after a transfer period of 30 s, detection of the radiation emitted by the 49 Ca for 600 s; (3) processing of the numerical data received, which are transmitted on line to a T 1600 calculator. The weight is found by comparing the activity induced in the unknown calcium mass with that induced in a phantom chosen as the activity standard. The reproducibility of the method is of the order of 3% (5% at the worst). The gross standardized result is edited automatically. For physical and clinical reasons, the hand is chosen as the reference part of the body in 70 control subjects. The local irradiation dose is less than 2 rem. The bone calcium content is 14.3+-1.9 g in men and 10.1+-1.3 g in women. In clinical application of the technique it is necessary to differentiate between the normal calcium content and the calcium content found with a pathological state. This makes it necessary to express the measurement in the form of a volume mass (rho). The volume of the hand skeleton (V in cm 3 ) is calculated from the corresponding bone surface (S in cm 2 ) measured by planimetry with the relationship V=8.925 exp 0.0205.S, found after studying 80 hand skeletons. In our control subjects the calcium bone volume mass was 0.288 g/cm 3 in men and 0.282 g/cm 3 in women. There is a very significant difference (p<0.001) in a population of 88 subjects with chronic renal insufficiencies at the terminal stage: rho=0.233 in men and 0.235 in women
40 CFR 264.254 - Monitoring and inspection.

Science.gov (United States)

2010-07-01

... Waste Piles § 264.254 Monitoring and inspection. (a) During construction or installation, liners (except in the case of existing portions of piles exempt from § 264.251(a)) and cover systems (e.g... increase in the permeability of the liner or cover. (b) While a waste pile is in operation, it must be...
48 CFR 53.204-1 - Safeguarding classified information within industry (DD Form 254, DD Form 441).

Science.gov (United States)

2010-10-01

... information within industry (DD Form 254, DD Form 441). 53.204-1 Section 53.204-1 Federal Acquisition....204-1 Safeguarding classified information within industry (DD Form 254, DD Form 441). The following... specified in subpart 4.4 and the clause at 52.204-2: (a) DD Form 254 (Department of Defense (DOD)), Contract...
Structure and formation mechanism of the transfermium isotope {sup 254}No.

Energy Technology Data Exchange (ETDEWEB)

Reiter, P.

1998-12-17

The ground-state band of the Z=102 isotope {sup 254}No has been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadruple deformation, {beta} = 0.27, is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of {sup 254}No up to spin 14 means that its fission barrier persists at least up to that spin.
Simulation and design of an electron beam ion source charge breeder for the californium rare isotope breeder upgrade

Directory of Open Access Journals (Sweden)

Clayton Dickerson

2013-02-01

Full Text Available An electron beam ion source (EBIS will be constructed and used to charge breed ions from the californium rare isotope breeder upgrade (CARIBU for postacceleration into the Argonne tandem linear accelerator system (ATLAS. Simulations of the EBIS charge breeder performance and the related ion transport systems are reported. Propagation of the electron beam through the EBIS was verified, and the anticipated incident power density within the electron collector was identified. The full normalized acceptance of the charge breeder with a 2 A electron beam, 0.024π mm mrad for nominal operating parameters, was determined by simulating ion injection into the EBIS. The optics of the ion transport lines were carefully optimized to achieve well-matched ion injection, to minimize emittance growth of the injected and extracted ion beams, and to enable adequate testing of the charge bred ions prior to installation in ATLAS.
36 CFR 254.33 - Road rights-of-way.

Science.gov (United States)

2010-07-01

... parcels subject to conveyance under this subpart are limited to those which are substantially surrounded by lands not owned by the United States. (b) Forest Service officials shall consider public road... Section 254.33 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP...
Long-term effects of an intracavitary treatment with californium-252 on normal tissue

International Nuclear Information System (INIS)

Sullivan, M.F.; Beamer, J.L.; Mahony, T.D.; Cross, F.T.; Lund, J.E.; Endres, G.W.R.

1976-01-01

About one hundred fifty swine were exposed to either radium-226 or californium-252 sources in the uterine cervix to determine an RBE for both acute and long-term effects. That value for early changes in the tissues at risk in the treatment of cervical cancer was between 6.2 and 6.8. The incidence of complications increased with time after exposure, especially among animals treated with 252 Cf. Analysis of rectal injury showed that ulceration occurred frequently within a year postexposure at doses between 1600 and 2400 rad calculated at 2 cm lateral to the source midline. Fat necrosis and smooth muscle atrophy, resulting in a local rectal stricture, were delayed changes observed in some animals. The lower ureter was the site for a greater frequency of complications than the GI tract. Ureteral stricture often occurred at doses of 1200 rad from 252 Cf and 7000 rad from 226 Ra. Observation of delayed effects in the uterine-cervix in animals held up to 4 years postexposure indicate that the RBE for 252 Cf may be increased to a value as high as 18, while repair may have even decreased it to about 5.6 in the rectum. Fifty swine are still being observed for long-term effects after doses above 800 rad from 252 Cf and 5000 rad from 226 Ra
75 FR 18047 - Amendment of Low Altitude Area Navigation Route T-254; Houston, TX

Science.gov (United States)

2010-04-09

...-254; Houston, TX AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends low altitude Area Navigation (RNAV) route T-254 in the Houston, TX, terminal area by... Houston, TX, terminal area. DATES: Effective Dates: 0901 UTC, June 3, 2010. The Director of the Federal...
In-beam spectroscopy of 253,254No

International Nuclear Information System (INIS)

Herzberg, R.D.; Amzal, N.; Bastin, J.E.; Brew, P.M.T.; Butler, P.A.; Chewter, A.J.C.; Hammond, N.J.; Humphreys, R.D.; Jones, G.D.; Becker, F.; Hauschild, K.; Houry, M.; Huerstel, A.; Cocks, J.F.C.; Dorvaux, O.; Greenlees, P.T.; Eskola, K.; Gerl, J.; Hessberger, F.; Helariutta, K.; Jones, P.M.; Julin, R.; Juutinen, S.; Kankaanpaeae, H.; Kettunen, H.; Khoo, T.L.; Korten, W.; Kuusiniemi, P.; Le Coz, Y.; Leino, M.; Leppaenen, C.J.; Lister, A.P.; Lucas, R.; Muikku, M.; Nieminen, P.; Page, R.D.; Page, T.; Rahkila, P.; Reiter, P.; Schlegel, Ch.; Scholey, C.; Sletten, G.; Stezowski, O.; Theisen, Ch.; Trzaska, W.H.; Uusitalo, J.; Wollersheim, H.J.

2002-01-01

In-beam conversion electron spectroscopy experiments have been performed on the transfermium nuclei 253, 254 No using the conversion electron spectrometer SACRED in nearly collinear geometry in conjunction with the gas-filled separator RITU at the University of Jyvaeskylae. The experimental setup is discussed and the spectra are compared to Monte Carlo simulations. The implications for the ground-state configuration of 253 No are discussed. (orig.)
Ground-State Band and Deformation of the Z = 102 Isotope N 254

International Nuclear Information System (INIS)

Reiter, P.; Khoo, T.L.; Lister, C.J.; Seweryniak, D.; Ahmad, I.; Alcorta, M.; Carpenter, M.P.; Cizewski, J.A.; Davids, C.N.; Gervais, G.; Greene, J.P.; Henning, W.F.; Janssens, R.V.; Lauritsen, T.; Siem, S.; Sonzogni, A.A.; Sullivan, D.; Uusitalo, J.; Wiedenhoever, I.; Amzal, N.; Butler, P.A.; Chewter, A.J.; Greenlees, P.T.; Herzberg, R.; Jones, G.D.; Cizewski, J.A.; Ding, K.Y.; Fotiades, N.; Fox, J.D.; Korten, W.; Leino, M.; Vetter, K.; Siem, S.

1999-01-01

The ground-state band of the Z=102 isotope 254 No has been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadrupole deformation, β=0.27 , is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of 254 No up to spin 14 means that its fission barrier persists at least up to that spin. copyright 1999 The American Physical Society
Feasibility and market potential of protein determination of wheat using californium-252

International Nuclear Information System (INIS)

Roberts, T.C. Jr.; Eckhoff, N.D.; Clack, R.W.; Roberts, T.C. Sr.

1976-01-01

To evaluate the feasibility of protein determination by capture gamma-ray analysis using californium-252 neutrons, an in-situ protein analysis system for use by grain handlers has been examined. Three 227 kilogram (approximately) lots of wheat were used to determine the amount of nitrogen present. Protein analyses by the Kjeldahl method were obtained from samples taken before and after the capture gamma-ray analyses. The 5.267-MeV gamma-ray was selected for use in this study as a compromise between efficiency and interference from other elements. The associated counting equipment was a multichannel analyzer with pulse shaping electronic and analysis computing equipment. A linear regression program was used to compare the regions of interest to the Kjeldahl protein averages. The counts composing each peak were summed and normalized using the total count of the hydrogen peak. The normalized nitrogen percentages indicate a significant correlation between the spectral regions and the Kjeldahl analyses. To a first approximation, the value of wheat is the wheat protein. At the present time, protein testing of wheat is destructive, cumbersome, and time-consuming as compared to the potential for capture gamma-ray analysis testing. Assuming that such a protein analysis unit can analyze 42 tonne of wheat per hour, over 120 units would be needed to monitor one-half the U.S. annual wheat production. A 0.5% improvement in processor realizations and grain throughput value of $167.00 per tonne will result in a projected savings of $150,000 per year per unit
75 FR 6319 - Proposed Amendment of Low Altitude Area Navigation Route T-254; Houston, TX

Science.gov (United States)

2010-02-09

... Amendment of Low Altitude Area Navigation Route T-254; Houston, TX AGENCY: Federal Aviation Administration... altitude Area Navigation (RNAV) route T-254 in the Houston, TX, terminal area by eliminating the segment... safety and the efficient use of the navigable airspace in the Houston, TX, terminal area. DATES: Comments...
Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source

International Nuclear Information System (INIS)

Cardoso, Antonio

1976-01-01

Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction 55 Mn (n.gamma) 56 Mn, high concentration of manganese in the matrix and short half - life of 56 Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions 56 Fe(n,p) 56 Mn and 59 Co (n, α) 56 were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)
37 CFR 254.2 - Definition of coin-operated phonorecord player.

Science.gov (United States)

2010-07-01

...-OPERATED PHONORECORD PLAYERS § 254.2 Definition of coin-operated phonorecord player. As used in this part..., currency, tokens, or other monetary units or their equivalent; (b) Is located in an establishment making no...
36 CFR 254.12 - Value equalization; cash equalization waiver.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Value equalization; cash... AGRICULTURE LANDOWNERSHIP ADJUSTMENTS Land Exchanges § 254.12 Value equalization; cash equalization waiver. (a..., either with or without adjustments of relative values as compensation for various costs, the parties to...
3C 254: the alignment effect and unification schemes

Science.gov (United States)

Bremer, M. N.

1997-01-01

3C 254 is a radio-loud quasar at z=0.734. Optical line and continuum emission from the underlying galaxy is clearly extended and aligned with the radio axis; the object shows the so-called `alignment effect' which is often seen in powerful radio galaxies. This is the clearest case yet of the continuum alignment effect in a radio-loud quasar. The object is one of the most lobe-dominated 3C quasars; the significance of the aligned emission in this source is discussed in terms of orientation-based unification schemes for radio-loud quasars and radio galaxies. 3C 254 is a very asymmetric radio source and it is shown that the radio structure on the side with the shortest nucleus-hotspot distance is interacting with the emission-line gas surrounding the quasar. It is also shown that the quasar is surrounded by an overdensity of faint objects, consistent with a cluster or group of galaxies around the object.

6 CFR 25.4 - Designation of qualified anti-terrorism technologies.

Science.gov (United States)

2010-01-01

... 6 Domestic Security 1 2010-01-01 2010-01-01 false Designation of qualified anti-terrorism... REGULATIONS TO SUPPORT ANTI-TERRORISM BY FOSTERING EFFECTIVE TECHNOLOGIES § 25.4 Designation of qualified anti-terrorism technologies. (a) General. The Under Secretary may Designate as a Qualified Anti-Terrorism...
47 CFR 25.254 - Special requirements for ancillary terrestrial components operating in the 1610-1626.5 MHz/2483.5...

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Special requirements for ancillary terrestrial components operating in the 1610-1626.5 MHz/2483.5-2500 MHz bands. 25.254 Section 25.254 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical...
Long-term effects of an intracavitary treatment with californium-252 on normal tissue. [Swine, /sup 226/Ra

Energy Technology Data Exchange (ETDEWEB)

Sullivan, M.F.; Beamer, J.L.; Mahony, T.D.; Cross, F.T.; Lund, J.E.; Endres, G.W.R.

1976-01-01

About one hundred fifty swine were exposed to either radium-226 or californium-252 sources in the uterine cervix to determine an RBE for both acute and long-term effects. That value for early changes in the tissues at risk in the treatment of cervical cancer was between 6.2 and 6.8. The incidence of complications increased with time after exposure, especially among animals treated with /sup 252/Cf. Analysis of rectal injury showed that ulceration occurred frequently within a year postexposure at doses between 1600 and 2400 rad calculated at 2 cm lateral to the source midline. Fat necrosis and smooth muscle atrophy, resulting in a local rectal stricture, were delayed changes observed in some animals. The lower ureter was the site for a greater frequency of complications than the GI tract. Ureteral stricture often occurred at doses of 1200 rad from /sup 252/Cf and 7000 rad from /sup 226/Ra. Observation of delayed effects in the uterine-cervix in animals held up to 4 years postexposure indicate that the RBE for /sup 252/Cf may be increased to a value as high as 18, while repair may have even decreased it to about 5.6 in the rectum. Fifty swine are still being observed for long-term effects after doses above 800 rad from /sup 252/Cf and 5000 rad from /sup 226/Ra.
Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

International Nuclear Information System (INIS)

Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.; Pikin, A. I.

2015-01-01

The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstrate stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this paper, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz
Understanding the different rotational behaviors of $^{252}$No and $^{254}$No in terms of high-order deformation

CERN Document Server

Liu, H L; Walker, P M

2012-01-01

Total Routhian surface calculations have been performed to investigate rapidly rotating transfermium nuclei, the heaviest nuclei accessible by detailed spectroscopy experiments. The observed fast alignment in $^{252}$No and slow alignment in $^{254}$No are well reproduced by the calculations incorporating high-order deformations. The different rotational behaviors of $^{252}$No and $^{254}$No can be understood for the first time in terms of $\\beta_6$ deformation that decreases the energies of the $\
Neutron flux characterization of californium-252 Neutron Research Facility at the University of Texas - Pan American by nuclear analytical technique

Science.gov (United States)

Wahid, Kareem; Sanchez, Patrick; Hannan, Mohammad

2014-03-01

In the field of nuclear science, neutron flux is an intrinsic property of nuclear reaction facilities that is the basis for experimental irradiation calculations and analysis. In the Rio Grande Valley (Texas), the UTPA Neutron Research Facility (NRF) is currently the only neutron facility available for experimental research purposes. The facility is comprised of a 20-microgram californium-252 neutron source surrounded by a shielding cascade containing different irradiation cavities. Thermal and fast neutron flux values for the UTPA NRF have yet to be fully investigated and may be of particular interest to biomedical studies in low neutron dose applications. Though a variety of techniques exist for the characterization of neutron flux, neutron activation analysis (NAA) of metal and nonmetal foils is a commonly utilized experimental method because of its detection sensitivity and availability. The aim of our current investigation is to employ foil activation in the determination of neutron flux values for the UTPA NSRF for further research purposes. Neutron spectrum unfolding of the acquired experimental data via specialized software and subsequent comparison for consistency with computational models lends confidence to the results.
Estimation of organic carbon deposition into forest ecosystems by determination of the spectral absorption of rainwater in range of ultraviolet radiation (SAC254)

International Nuclear Information System (INIS)

Bartels, U.

1988-01-01

Organic compounds are mostly neglected within deposition measurement programs because their determination is expensive and complicated. A very simple and rapid estimation of total organic carbon (TOC) is possible by determination of the spectral absorption coefficient in the range of ultraviolet radiation at 254 nm wave-length (SAC 254 ): TOC (mg/1) = 0,5 SAC 254 (m −1 ) - 0,15 (author) [de
Ferric ion mediated photochemical decomposition of perfluorooctanoic acid (PFOA) by 254 nm UV light

International Nuclear Information System (INIS)

Wang Yuan; Zhang Pengyi; Pan Gang; Chen Hao

2008-01-01

The great enhancement of ferric ion on the photochemical decomposition of environmentally persistent perfluorooctanoic acid (PFOA) under 254 nm UV light was reported. In the presence of 10 μM ferric ion, 47.3% of initial PFOA (48 μM) was decomposed and the defluorination ratio reached 15.4% within 4 h reaction time. While the degradation and defluorination ratio greatly increased to 80.2% and 47.8%, respectively, when ferric ion concentration increased to 80 μM, and the corresponding half-life was shortened to 103 min. Though the decomposition rate was significantly lowered under nitrogen atmosphere, PFOA was efficiently decomposed too. Other metal ions like Cu 2+ and Zn 2+ also slightly improved the photochemical decomposition of PFOA under irradiation of 254 nm UV light. Besides fluoride ion, other intermediates during PFOA decomposition including formic acid and five shorter-chain perfluorinated carboxylic acids (PFCAs) with C7, C6, C5, C4 and C3, respectively, were identified and quantified by IC or LC/MS. The mixture of PFOA and ferric ion had strong absorption around 280 nm. It is proposed that PFOA coordinates with ferric ion to form a complex, and its excitation by 254 nm UV light leads to the decomposition of PFOA in a stepwise way
25 CFR 900.254 - May the contractor be reimbursed for actual and reasonable “wind up costs” incurred after the...

Science.gov (United States)

2010-04-01

... up costs” incurred after the effective date of rescission? Yes. ... 25 Indians 2 2010-04-01 2010-04-01 false May the contractor be reimbursed for actual and reasonable âwind up costsâ incurred after the effective date of rescission? 900.254 Section 900.254 Indians...
Substitution of Tyr254 with Phe at the active site of flavocytochrome b2: consequences on catalysis of lactate dehydrogenation

International Nuclear Information System (INIS)

Dubois, J.; Chapman, S.K.; Mathews, F.S.; Reid, G.A.; Lederer, F.

1990-01-01

A role for Tyr254 in L-lactate dehydrogenation catalyzed by flavocytochrome b2 has recently been proposed on the basis of the known active-site structure and of studies that had suggested a mechanism involving the initial formation of a lactate carbanion. This role is now examined after replacement of Tyr254 with phenylalanine. The kcat is decreased about 40-fold, Km for lactate appears unchanged, and the mainly rate-limiting step is still alpha-hydrogen abstraction, as judged from the steady-state deuterium isotope effect. Modeling studies with lactate introduced into the active site indicate two possible substrate conformations with different hydrogen-bonding partners for the substrate hydroxyl. If the hydrogen bond is formed with Tyr254, as was initially postulated, the mechanism must involve removal by His373 of the C2 hydrogen, with carbanion formation. If, in the absence of the Tyr254 phenol group, the hydrogen bond is formed with His373 N3, the substrate is positioned in such a way that the reaction must proceed by hydride transfer. Therefore the mechanism of the Y254F enzyme was investigated so as to distinguish between the two mechanistic possibilities. 2-Hydroxy-3-butynoate behaves with the mutant as a suicide reagent, as with the wild-type enzyme. Similarly, the mutant protein also catalyzes the reduction and the dehydrohalogenation of bromopyruvate under transhydrogenation conditions
Corrective Action Plan for Corrective Action Unit 254: Area 25 R-MAD Decontamination Facility Nevada Test Site, Nevada

International Nuclear Information System (INIS)

Obi, C.M.

2000-01-01

The Area 25 Reactor Maintenance, Assembly, and Disassembly Decontamination Facility is identified in the Federal Facility Agreement and Consent Order (FFACO) as Corrective Action Unit (CAU) 254. CAU 254 is located in Area 25 of the Nevada Test Site and consists of a single Corrective Action Site CAS 25-23-06. CAU 254 will be closed, in accordance with the FFACO of 1996. CAU 254 was used primarily to perform radiological decontamination and consists of Building 3126, two outdoor decontamination pads, and surrounding soil within an existing perimeter fence. The site was used to decontaminate nuclear rocket test-car hardware and tooling from the early 1960s through the early 1970s, and to decontaminate a military tank in the early 1980s. The site characterization results indicate that, in places, the surficial soil and building materials exceed clean-up criteria for organic compounds, metals, and radionuclides. Closure activities are expected to generate waste streams consisting of nonhazardous construction waste. petroleum hydrocarbon waste, hazardous waste, low-level radioactive waste, and mixed waste. Some of the wastes exceed land disposal restriction limits and will require off-site treatment before disposal. The recommended corrective action was revised to Alternative 3- ''Unrestricted Release Decontamination, Verification Survey, and Dismantle Building 3126,'' in an addendum to the Correction Action Decision Document
Enhanced escape rate for Hg 254 nm resonance radiation in fluorescent lamps

International Nuclear Information System (INIS)

Lawler, James E; Raizen, Mark G

2013-01-01

The potential of the low-cost MAGIS isotopic separation method to improve fluorescent lamp efficacy is explored using resonance radiation transport simulations. New Hg isotopic mixes are discovered that yield escape rates for 254 nm Hg I resonance radiation equal to 117% to 122% of the rate for a natural isotopic mix under the same lamp conditions. (paper)
Coulomb dissociation of {sup 8}B at 254 A MeV

Energy Technology Data Exchange (ETDEWEB)

Suemmerer, K; Boue, F; Baumann, T; Geissel, H; Hellstroem, M; Koczon, P; Schwab, E; Schwab, W; Senger, P; Surowiecz, A [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); Iwasa, N; Ozawa, A [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); [RIKEN Institute of Physical and Chemical Research, Saitama (Japan); Surowka, G [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Blank, B; Czajkowski, S; Marchand, C; Pravikoff, M S [Centre d` Etudes Nucleaires de Bordeaux-Gradignan, 33 (France); Foerster, A; Lauer, F; Oeschler, H; Speer, J; Sturm, C; Uhlig, F; Wagner, A [Technische Univ. Darmstadt (Germany); Gai, M [Connecticut Univ., Storrs, CT (United States). Dept. of Physics; Grosse, E [Inst. fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, Dresden (Germany); Kohlmeyer, B [Philipps Univ., Marburg (Germany). Fachbereich Physik; Kulessa, R; Walus, W [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Motobayashi, T [Rikkyo Univ., Tokyo (Japan). Dept. of Physics; Teranishi, T [RIKEN Institute of Physical and Chemical Research, Saitama (Japan)

1998-06-01

As an alternative method for determining the astrophysical S-factor for the {sup 7}Be(p,{gamma}){sup 8}B reaction we have measured the Coulomb dissociation of {sup 8}B at 254 A MeV. From our preliminary results, we obtain good agreement with both the accepted direct-reaction measurements and the low-energy Coulomb dissociation study of Iwasa et al. performed at about 50 A MeV. (orig.)
Coulomb dissociation of 8B at 254 MeV/u

International Nuclear Information System (INIS)

Surowka, G.; Iwasa, N.; Boue, F.

1999-01-01

As an alternative method to determine the cross section of 7 Be (p, γ) 8 B, the Coulomb dissociation reaction 8 B → 7 Be + p at E inc = 254 MeV/u was measured. Our preliminary results show the dominant role of the dipole excitation in the Coulomb break-up process. The extracted astrophysical S 17 factor is consistent with the lower-value results both of the direct-capture studies, and the RIKEN Coulomb-dissociation experiment at ∼ 50 MeV/u. (author)
Comparative mutagenesis and interaction between near-ultraviolet (313- to 405-nm) and far-ultraviolet (254-nm) radiation in Escherichia coli strains with differing repair capabilities

International Nuclear Information System (INIS)

Turner, M.A.; Webb, R.B.

1981-01-01

Comparative mutagenesis and possible synergistic interaction between broad-spectrum (313- to 405-nm) near-ultraviolet (black light bulb [BLB]) radiation and 254-nm radiation were studied in Escherichia coli strains WP2 (wild type), WP2s (uvrA), WP10 (recA), WP6 (polA), WP6s (polA uvrA), WP100 (uvrA recA), and WP5 (lexA). With BLB radiation, strains WP2s and WP6s demonstrated a high level of mutagenesis, whereas strains WP2, WP5, WP6, WP10, and WP100 did not demonstrate significant mutagenesis. In contrast, 254-nm radiation was mutagenic in strains WP2, WP2s, WP6, and WP6s, but strains WP5, WP10, and WP100 were not significantly mutated. The absence of mutagenesis by BLB radiation in lexA and recA strains WP10, WP5, and WP100 suggests that lex + rec + repair may play a major role in mutagenesis by both BLB and 254-nm radiation. The hypothesis that BLB radiation selectively inhibits rec + lex + repair was tested by sequential BLB-254 nm radiation. With strain WP2, a fluence of 30 J/m 2 at 254 nm induced trp + revertants at a frequency of 15 x 10 -6 . However, when 10 5 J/m 2 or more BLB radiation preceded the 254-nm exposure, no trp + revertants could be detected. A similar inhibition of 254-nm mutagenesis was observed with strain WP6 (polA). However, strains WP2s (uvrA) and WP6s (polA uvrA) showed enhanced 254-nm mutagenesis when a prior exposure to BLB radiation was given
Optical and near-infrared study of the AM Herculis-type binary CW 1103 + 254

Energy Technology Data Exchange (ETDEWEB)

Bailey, J [Anglo-Australian Observatory, Epping (Australia); Watts, D J [Tasmania Univ., Sandy Bay (Australia). Dept. of Physics; Sherrington, M R [Leicester Univ. (UK). Dept. of Astronomy

1985-07-15

The AM Herculis-type binary CW 1103+254 has been observed using optical and near-infrared photometry and polarimetry, and optical spectroscopy and spectropolarimetry. It is found that from such a set of observations it is relatively easy to distinguish all the main components of the system.
A clinico-radiological study on 254 cases of pontine high signals on magnetic resonance imaging in relation to brain stem semiology

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

1993-11-01

A total of 254 patients who were proved to have pontine high intensity areas on T[sub 2]-weighted magnetic resonance imaging (MRI) were analyzed in relation to brain stem semiology. A comparative study on MRI and MR angiography was made between 254 patients with pontine high signals and 276 control cases showing no abnormality either on T[sub 1] or T[sub 2]-weighted images. Of the 254 patients, 62 had transient subjective complaints such as vertigo-dizziness. Supratentorial high signals, basilar artery tortuousness and vertebral artery asymmetry on MR angiography were seen more frequently in patients with pontine high signals than in the controls. In conclusion, pontine high signals may result from diffuse arteriosclerosis and MR angiography is considered to be a useful screening method. (author).
Crítica textual y estilo: nota a Farsalia I 254

Directory of Open Access Journals (Sweden)

Antonio Holgado Redondo

1981-12-01

Full Text Available Almost every Lucan's manuscript has in Pharsalia I 254 the variant furentem (only one gives ruentem, but almost every one of the editors prefers ruentem. The acceptance of ruentem is due to the nearby presence of a furentum and a furoris. Here we maintain furentem as the right reading, on grounds of Lucan's familiar stylistic procedure of repetition of the key terms of a passage. The poetic value of this repetition is endorsed in modern times by R. Jakobson and S. R. Levin.
Study of the average charge states of 188Pb and 252,254No ions at the gas-filled separator TASCA

International Nuclear Information System (INIS)

Khuyagbaatar, J.; Ackermann, D.; Andersson, L.-L.; Ballof, J.; Brüchle, W.; Düllmann, Ch.E.; Dvorak, J.; Eberhardt, K.; Even, J.; Gorshkov, A.; Graeger, R.; Heßberger, F.-P.; Hild, D.; Hoischen, R.; Jäger, E.; Kindler, B.

2012-01-01

The average charge states of 188 Pb and 252,254 No ions in dilute helium gas were measured at the gas-filled recoil separator TASCA. Hydrogen gas was also used as a filling gas for measurements of the average charge state of 254 No. Helium and hydrogen gases at pressures from 0.2 mbar to 2.0 mbar were used. A strong dependence of the average charge state on the pressure of the filling gases was observed for both, helium and hydrogen. The influence of this dependence, classically attributed to the so-called “density effect”, on the performance of TASCA was investigated. The average charge states of 254 No ions were also measured in mixtures of helium and hydrogen gases at low gas pressures around 1.0 mbar. From the experimental results simple expressions for the prediction of average charge states of heavy ions moving in rarefied helium gas, hydrogen gas, and in their mixture were derived.
Decay and Fission Hindrance of Two- and Four-Quasiparticle K Isomers in ^{254}Rf.

Science.gov (United States)

David, H M; Chen, J; Seweryniak, D; Kondev, F G; Gates, J M; Gregorich, K E; Ahmad, I; Albers, M; Alcorta, M; Back, B B; Baartman, B; Bertone, P F; Bernstein, L A; Campbell, C M; Carpenter, M P; Chiara, C J; Clark, R M; Cromaz, M; Doherty, D T; Dracoulis, G D; Esker, N E; Fallon, P; Gothe, O R; Greene, J P; Greenlees, P T; Hartley, D J; Hauschild, K; Hoffman, C R; Hota, S S; Janssens, R V F; Khoo, T L; Konki, J; Kwarsick, J T; Lauritsen, T; Macchiavelli, A O; Mudder, P R; Nair, C; Qiu, Y; Rissanen, J; Rogers, A M; Ruotsalainen, P; Savard, G; Stolze, S; Wiens, A; Zhu, S

2015-09-25

Two isomers decaying by electromagnetic transitions with half-lives of 4.7(1.1) and 247(73) μs have been discovered in the heavy ^{254}Rf nucleus. The observation of the shorter-lived isomer was made possible by a novel application of a digital data acquisition system. The isomers were interpreted as the K^{π}=8^{-}, ν^{2}(7/2^{+}[624],9/2^{-}[734]) two-quasineutron and the K^{π}=16^{+}, 8^{-}ν^{2}(7/2^{+}[624],9/2^{-}[734])⊗8^{-}π^{2}(7/2^{-}[514],9/2^{+}[624]) four-quasiparticle configurations, respectively. Surprisingly, the lifetime of the two-quasiparticle isomer is more than 4 orders of magnitude shorter than what has been observed for analogous isomers in the lighter N=150 isotones. The four-quasiparticle isomer is longer lived than the ^{254}Rf ground state that decays exclusively by spontaneous fission with a half-life of 23.2(1.1) μs. The absence of sizable fission branches from either of the isomers implies unprecedented fission hindrance relative to the ground state.

Human Factors evaluation of LCS 254 and 255

International Nuclear Information System (INIS)

Goffe, L.; Held, J.E.

1993-01-01

This report includes the results of the Human Factors evaluation of the local control stations (LCS) 254 and 255 performed by Savannah River Technology Center (SRTC) Human Factors. Recommendations are included in order that the panel designs will be upgraded to comply with human engineering design guidelines. Figures 1 and 2 are included as examples of recommended changes. Also, consideration was given to including the proposed engineering changes which are currently on-going for LCS 255. Appendix A identifies the human engineering requirements from NUREG-0700 which were used in the evaluation process, and the areas of the design which do not comply with the guidelines. Those areas of the panel design which fail to comply with the human engineering guidelines are label location, label content, location aids, panel layout, and control display integration. Each of these design deficiencies and proposed corrections are described in this report
Californium interrogation prompt neutron (CIPN) instrument for non-destructive assay of spent nuclear fuel—Design concept and experimental demonstration

International Nuclear Information System (INIS)

Henzlova, D.; Menlove, H.O.; Rael, C.D.; Trellue, H.R.; Tobin, S.J.; Park, Se-Hwan; Oh, Jong-Myeong; Lee, Seung-Kyu; Ahn, Seong-Kyu; Kwon, In-Chan; Kim, Ho-Dong

2016-01-01

This paper presents results of the first experimental demonstration of the Californium Interrogation Prompt Neutron (CIPN) instrument developed within a multi-year effort launched by the Next Generation Safeguards Initiative Spent Fuel Project of the United States Department of Energy. The goals of this project focused on developing viable non-destructive assay techniques with capabilities to improve an independent verification of spent fuel assembly characteristics. For this purpose, the CIPN instrument combines active and passive neutron interrogation, along with passive gamma-ray measurements, to provide three independent observables. This paper describes the initial feasibility demonstration of the CIPN instrument, which involved measurements of four pressurized-water-reactor spent fuel assemblies with different levels of burnup and two initial enrichments. The measurements were performed at the Post-Irradiation Examination Facility at the Korea Atomic Energy Institute in the Republic of Korea. The key aim of the demonstration was to evaluate CIPN instrument performance under realistic deployment conditions, with the focus on a detailed assessment of systematic uncertainties that are best evaluated experimentally. The measurements revealed good positioning reproducibility, as well as a high degree of insensitivity of the CIPN instrument's response to irregularities in a radial burnup profile. Systematic uncertainty of individual CIPN instrument signals due to assembly rotation was found to be <4.5%, even for assemblies with fairly extreme gradients in the radial burnup profile. These features suggest that the CIPN instrument is capable of providing a good representation of assembly average characteristics, independent of assembly orientation in the instrument.
Californium interrogation prompt neutron (CIPN) instrument for non-destructive assay of spent nuclear fuel—Design concept and experimental demonstration

Energy Technology Data Exchange (ETDEWEB)

Henzlova, D., E-mail: henzlova@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Menlove, H.O.; Rael, C.D.; Trellue, H.R.; Tobin, S.J. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Park, Se-Hwan; Oh, Jong-Myeong; Lee, Seung-Kyu; Ahn, Seong-Kyu; Kwon, In-Chan; Kim, Ho-Dong [Korea Atomic Energy Research Institute, Daejeong (Korea, Republic of)

2016-01-11

This paper presents results of the first experimental demonstration of the Californium Interrogation Prompt Neutron (CIPN) instrument developed within a multi-year effort launched by the Next Generation Safeguards Initiative Spent Fuel Project of the United States Department of Energy. The goals of this project focused on developing viable non-destructive assay techniques with capabilities to improve an independent verification of spent fuel assembly characteristics. For this purpose, the CIPN instrument combines active and passive neutron interrogation, along with passive gamma-ray measurements, to provide three independent observables. This paper describes the initial feasibility demonstration of the CIPN instrument, which involved measurements of four pressurized-water-reactor spent fuel assemblies with different levels of burnup and two initial enrichments. The measurements were performed at the Post-Irradiation Examination Facility at the Korea Atomic Energy Institute in the Republic of Korea. The key aim of the demonstration was to evaluate CIPN instrument performance under realistic deployment conditions, with the focus on a detailed assessment of systematic uncertainties that are best evaluated experimentally. The measurements revealed good positioning reproducibility, as well as a high degree of insensitivity of the CIPN instrument's response to irregularities in a radial burnup profile. Systematic uncertainty of individual CIPN instrument signals due to assembly rotation was found to be <4.5%, even for assemblies with fairly extreme gradients in the radial burnup profile. These features suggest that the CIPN instrument is capable of providing a good representation of assembly average characteristics, independent of assembly orientation in the instrument.
Stability of trans-fermium elements at high spin: Measuring the fission barrier of 254No

International Nuclear Information System (INIS)

Henning, Greg

2012-01-01

Super heavy nuclei provide opportunities to study nuclear structure near three simultaneous limits: in charge Z, spin I and excitation energy E*. These nuclei exist only because of a fission barrier, created by shell effects. It is therefore important to determine the fission barrier and its spin dependence B f (I), which gives information on the shell energy E(shell)(I). Theoretical calculations predict different fission barrier heights from B f (I = 0) = 6.8 MeV for a macro-microscopic model to 8.7 MeV for Density Functional Theory calculations using the Gogny or Skyrme interactions. Hence, a measurement of B f provides a test for theories.To investigate the fission barrier, an established method is to measure the rise of fission with excitation energy, characterized by the ratio of decay widths Γ(fission)/Γ(total), using transfer reactions. However, for heavy elements such as 254 No, there is no suitable target for a transfer reaction. We therefore rely on the complementary decay widths ratio Γ γ /Γ(fission) and its spin dependence, deduced from the entry distribution (I, E*).Measurements of the gamma-ray multiplicity and total energy for 254 No have been performed with beam energies of 219 and 223 MeV in the reaction 208 Pb( 48 Ca,2n) at ATLAS (Argonne Tandem Linac Accelerator System). The 254 No gamma rays were detected using the Gammasphere array as a calorimeter - as well as the usual high resolution γ-ray detector. Coincidences with evaporation residues at the Fragment Mass Analyzer focal plane separated 254 No gamma rays from those from fission fragments, which are ≥ 10 6 more intense. From this measurement, the entry distribution - i.e. the initial distribution of I and E* - is constructed. Each point (I,E*) of the entry distribution is a point where gamma decay wins over fission and, therefore, gives information on the fission barrier. The measured entry distributions show an increase in the maximum spin and excitation energy from 219 to 223 Me
40 CFR 60.254 - Standards for coal processing and conveying equipment, coal storage systems, transfer and loading...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for coal processing and conveying equipment, coal storage systems, transfer and loading systems, and open storage piles. 60.254... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Coal Preparation...
Photooxidation of polystyrene: irradiation at 254 and 365 nm

International Nuclear Information System (INIS)

Otocka, E.P.; Curran, S.; Porter, R.S.

1983-01-01

Studies have been made of the near surface photooxidation of atactic polystyrene films prepared in the absence of air. The samples were photooxidized on exposure to air at two frequencies, 254 and 365 nm, using a calibrated mercury irradiation source with filters. Most studies were made at 40 0 C and as a function of irradiation time with the reactions characterized by changes in molecular weight and composition. The former was evaluated by gel permeation chromatography and the latter by transmission Fourier transform infrared ir spectroscopy and by multiple-internal-reflectance ir spectra using different angles and different crystals to evaluate compositions as a function of film depth. Species identified in photooxidation include the generation of hydroperoxides and the appearance of carbonyl bands with the latter identified by the spectral shift associated with the exposure of the photooxidized polystyrene surface to ammonia. These results suggest that principal products of near-surface oxidation of polystyrene are carboxylic acids. 6 figures, 1 table
30 CFR 254.26 - What information must I include in the “Worst case discharge scenario” appendix?

Science.gov (United States)

2010-07-01

... and environmental importance, if any, specified in the appropriate Area Contingency Plan(s). (d) A... COAST LINE Oil-Spill Response Plans for Outer Continental Shelf Facilities § 254.26 What information... Control Systems for Use on Water, and ASTM F818-93, Standard Definitions Relating to Spill Response...
Removal of sulfamethoxazole, ibuprofen and nitrobenzene by UV and UV/chlorine processes: A comparative evaluation of 275 nm LED-UV and 254 nm LP-UV.

Science.gov (United States)

Kwon, Minhwan; Yoon, Yeojoon; Kim, Seonbaek; Jung, Youmi; Hwang, Tae-Mun; Kang, Joon-Wun

2018-05-15

The aim of this study is to evaluate the micropollutant removal capacity of a 275 nm light-emitting diode (LED)-UV/chlorine system. The sulfamethoxazole, ibuprofen, and nitrobenzene removal efficiencies of this system were compared with those of a conventional 254 nm low-pressure (LP)-UV system as a function of the UV dose. In a direct photolysis system, the photon reactivity of sulfamethoxazole is higher than that of nitrobenzene and ibuprofen at both wavelengths. The molar absorption coefficients and quantum yields of each micropollutant were as follows: sulfamethoxazole (ε SMX, 275 nm protonated  = 17,527 M -1  cm -1 , Φ SMX, 275 nm protonated  = 0.239, ε SMX, 275 nm deprotonated  = 8430 M -1  cm -1 , and Φ SMX, 275 nm deprotonated  = 0.026), nitrobenzene (ε NB, 275 nm  = 7176 M -1  cm -1 and Φ NB, 275 nm  = 0.057), and ibuprofen (ε NB, 275 nm  = 200 M -1  cm -1 and Φ IBF, 275 nm  = 0.067). The photon reactivity of chlorine species, i.e., HOCl and OCl-, were determined at 275 nm (ε HOCl, 275 nm  = 28 M -1  cm -1 , Φ HOCl, 275 nm  = 1.97, ε OCl-, 275 nm  = 245 M -1  cm -1 , and Φ OCl-, 275 nm  = 0.8), which indicate that the decomposition rate of OCl - is higher and that of HOCl is lower by 275 nm photolysis than that by 254 nm photolysis (ε HOCl, 254 nm  = 60 M -1  cm -1 , Φ HOCl, 254 nm  = 1.46, ε OCl-, 254 nm  = 58 M -1  cm -1 , and Φ OCl-, 254 nm  = 1.11). In the UV/chlorine system, the removal rates of ibuprofen and nitrobenzene were increased by the formation of OH and reactive chlorine species. The 275-nm LED-UV/chlorine system has higher radical yields at pH 7 and 8 than the 254 nm LP-UV/chlorine system. Copyright © 2018 Elsevier B.V. All rights reserved.
Uretritis masculina Estudio prospectivo de 254 casos

Directory of Open Access Journals (Sweden)

Federico Diaz G.

1983-06-01

Full Text Available La uretritis no gonocócica (UNG fue la forma predominante (78,0% en una serie de 254 hombres con síndrome de uretritis, estudiados prospectivamente en 1982. La Trichomonas vaginalis estuvo presente en el 4.0% de los casos de UNG. Con base en la comparación entre los pacientes de uretritis gonocócica (UG y los de UNO, puede proponerse un perfil de los segundo que oriente al médico en su sospecha diagnóstica: mayor probabilidad de no hallar secreción uretral o de que Ésta sea escasa y de las modalidades acuosa, mucoide o mixta; también mayor probabilidad de un período de incubación por encima de 9 días y de una evolución superior a un mes. A pesar de tales indicios hay mucha superposición clínica entre las dos formas de uretritis por lo que sigue siendo valedera la recomendación de recurrir al Gram como procedimiento confiable y económico para establecer el diagnóstico diferencial. Se llama la atención hacia la necesidad de disponer de datos sobre uretritis en otros grupos socioeconómicos y de investigar aspectos como la frecuencia en nuestro medio del síndrome de uretritis postgonocócica (U PG.
Alimentation impact of treatments of 254 oropharyngeal cancers (1998-2003).

Science.gov (United States)

Buiret, Guillaume; Daveau, Clémentine; Landry, Guillaume; Colin, Carole; Pignat, Jean-Christian; Poupart, Marc

2011-01-01

Objective. To analyze the functional impact of the various possible treatments of oropharyngeal squamous cell carcinomas to find the main prognostic factors of dysphagia induced by these treatments. Patients. Clinical data from 254 patients treated for squamous cell carcinoma of the oropharynx between 1998 and 2003 were retrospectively analyzed. A multivariate model enabled us to evaluate the role of each potentially harmful factor on swallowing. Main Outcome Measures. The significant factors influencing the consumption of liquid, pasty, and normal food were the same: the initial T stage and the type of treatment. Conclusion. Whatever the possible and selected treatment was, the impact on the functional capacities, and thus, the quality of life of the patients was considerable. Even though we could not significantly demonstrate exclusive radiotherapy caused more long-term undesirable effects than surgery followed by radiotherapy, our daily practice has shown that we should favour the latter.
Freeze drying method for preparing radiation source material

International Nuclear Information System (INIS)

Mosley, W.C.; Smith, P.K.

1976-01-01

Fabrication of a neutron source is specifically claimed. A palladium/californium solution is freeze dried to form a powder which, through conventional powder metallurgy, is shaped into a source containing the californium evenly distributed through a palladium metal matrix. (E.C.B.)
Reactor production of 252Cf and transcurium isotopes

International Nuclear Information System (INIS)

Alexander, C.W.; Halperin, J.; Walker, R.L.; Bigelow, J.E.

1990-01-01

Berkelium, californium, einsteinium, and fermium are currently produced in the High Flux Isotope Reactor (HFIR) and recovered in the Radiochemical Engineering Development Center (REDC) at the Oak Ridge National Laboratory (ORNL). All the isotopes are used for research. In addition, 252 Cf, 253 Es, and 255 Fm have been considered or are used for industrial or medical applications. ORNL is the sole producer of these transcurium isotopes in the western world. A wide range of actinide samples were irradiated in special test assemblies at the Fast Flux Test Facility (FFTF) at Hanford, Washington. The purpose of the experiments was to evaluate the usefulness of the two-group flux model for transmutations in the special assemblies with an eventual goal of determining the feasibility of producing macro amounts of transcurium isotopes in the FFTF. Preliminary results from the production of 254g Es from 252 Cf will be discussed. 14 refs., 5 tabs
Complete Genome Sequence of Streptomyces albus SM254, a Potent Antagonist of Bat White-Nose Syndrome Pathogen Pseudogymnoascus destructans.

Science.gov (United States)

Badalamenti, Jonathan P; Erickson, Joshua D; Salomon, Christine E

2016-04-14

We sequenced and annotated the complete 7,170,504-bp genome of a novel secondary metabolite-producingStreptomycesstrain,Streptomyces albusSM254, isolated from copper-rich subsurface fluids at ~220-m depth within the Soudan Iron Mine (Soudan, MN, USA). Copyright © 2016 Badalamenti et al.
The O-GlcNAc Transferase Intellectual Disability Mutation L254F Distorts the TPR Helix.

Science.gov (United States)

Gundogdu, Mehmet; Llabrés, Salomé; Gorelik, Andrii; Ferenbach, Andrew T; Zachariae, Ulrich; van Aalten, Daan M F

2018-05-17

O-linked β-N-acetyl- D -glucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential post-translational modification that is abundant in the brain. Recently, OGT mutations have been associated with intellectual disability, although it is not understood how they affect OGT structure and function. Using a multi-disciplinary approach we show that the L254F OGT mutation leads to conformational changes of the tetratricopeptide repeats and reduced activity, revealing the molecular mechanisms contributing to pathogenesis. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Kinetics and mechanism investigation on the destruction of oxytetracycline by UV-254nm activation of persulfate.

Science.gov (United States)

Liu, Yiqing; He, Xuexiang; Fu, Yongsheng; Dionysiou, Dionysios D

2016-03-15

Oxytetracycline (OTC), an important broad-spectrum antibiotic, has been detected extensively in various environmental systems, which may have a detrimental impact on ecosystem and human health through the development of drug resistant bacteria and pathogens. In this study, the degradation of OTC was evaluated by UV-254nm activated persulfate (PS). The observed UV fluence based pseudo first-order rate constant (kobs) was found to be the highest at near neutral pH conditions (pH 5.5-8.5). Presence of various natural water constituents had different effects on OTC degradation, with a significant enhancement in the presence of bicarbonate or Cu(2+). Limited elimination of total organic carbon (TOC) and PS was observed during the mineralization of OTC. Transformation byproducts in the presence and absence of hydroxyl radical scavenging agent tert-butanol (t-BuOH) were identified using ultra-high definition accurate-mass quadrupole time-of-flight liquid chromatography/mass spectrometer (LC-QTOF/MS). Potential OTC degradation mechanism was subsequently proposed revealing four different reaction pathways by SO4(-) reaction including hydroxylation (+16Da), demethylation (-14Da), decarbonylation (-28Da) and dehydration (-18Da). This study suggests that UV-254nm/PS is a promising treatment technology for the control of water pollution caused by emerging contaminants such as OTC. Copyright © 2015 Elsevier B.V. All rights reserved.
Trends in radioisotope development and utilization in the United States

Energy Technology Data Exchange (ETDEWEB)

Mott, W E [Energy Research and Development Administration, Washington, D.C. (USA)

1976-06-01

The current trends in radioisotope and radiation technology in the United States are overviewed with emphasis on the developments since the 1973 Conference. The comments focus primarily on the research and development activities receiving the most attention today from the various agencies of the Government. Among the many available radionuclides, technetium-99m has played the single most important role for making possible the developments in the field of nuclear medicine. Many other short lived medium-lived nuclides are applied in the fields of nuclear medicine, cardiac pacemaker, artificial heart, and blood irradiator. Radiation processing is now firmly established in the United States. The trends in sewage treatment, polymer-impregnated materials, bioengineering, and food irradiation are reviewed. The programs for californium-252, strontium-90, cesium-137, plutonium-238, and krypton-85 are also reviewed. The author concludes this paper with the acknowledgement that Japanese researchers have contributed to and have been closely involved in many of the programs discussed. Of particular note is the participation in the clinical phase of the californium-252 radiotherapy program. Several Japanese hospitals have been cooperating with the United States since the very beginning of the californium-252 program in determining the value of the californium-252 neutron therapy. The research being performed is unique, and will contribute greatly to the decisions on the ultimate future of californium-252 for therapeutic purposes.
Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

International Nuclear Information System (INIS)

Fan, Yiqiang; Liu, Yang; Li, Huawei; Foulds, Ian G

2012-01-01

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct printing of the mask onto a polymer sheet using a commercial wax printer. The wax layer was then transferred to a PMMA substrate using a thermal laminator, exposed using deep-UV (with a wavelength of 254 nm), developed in an IPA:water solution, and completed by bonding on a PMMA cap layer. A sample microfluidic device fabricated with this method is also presented, with the microchannel as narrow as 50 µm. The whole process is easy to perform without the requirement for any microfabrication facilities. (technical note)
Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

KAUST Repository

Fan, Yiqiang

2012-01-13

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct printing of the mask onto a polymer sheet using a commercial wax printer. The wax layer was then transferred to a PMMA substrate using a thermal laminator, exposed using deep-UV (with a wavelength of 254 nm), developed in an IPA:water solution, and completed by bonding on a PMMA cap layer. A sample microfluidic device fabricated with this method is also presented, with the microchannel as narrow as 50 μm. The whole process is easy to perform without the requirement for any microfabrication facilities. © 2012 IOP Publishing Ltd.
Branching ratios of α-decay to ground and excited states of Fm, Cf, Cm and Pu

Science.gov (United States)

Hassanabadi, H.; Hosseini, S. S.

2018-06-01

We use the well-known Wentzel-Kramers-Brillouin (WKB) barrier penetration probability to calculate α-decay branching ratios for ground and excited states of heavy even-even nuclei of Fermium (248-254Fm), Californium (244-252Cf), Curium (238-248Cm) and Plutonium (234-244Pu) with 94 ≤Zp ≤100. We obtained the branching ratios for the excited states of daughter nucleus by the α-decay energy (Qα), the angular momentum of α-particle (ℓα), and the excitation probability of the daughter nucleus with the excitation energy of state ℓ in the daughter nucleus (i.e. Eℓ*). α-Decay half-lives have been evaluated by using the proximity potential model for the heavy even-even nuclei. We have reported the half-lives and compared the results with the experimental data. The theoretical branching ratios of α-transitions in our calculation are found to agree with the available experimental data well for 0+→ 0+, 0+→ 2+, 0+→ 4+, 0+→ 6+ and 0+ → 8+α-transitions.
Nuclear structure data from in beam and decay studies around 254No

International Nuclear Information System (INIS)

Jones, P.

2005-01-01

The study of trans-fermium nuclei, the heaviest nuclei for which in-beam spectroscopy studies are possible has provided over recent years a rich tapestry of data. These have enhanced the mean field theories important for the prediction of nuclear properties at the limits of the nuclear chart. Developments in spectrometer and data-acquisition techniques at the Department of Physics, University of Jyvaskyla have further enhanced the studies. Utilising the RITU gas-filled spectrometer, the GREAT focal plane spectrometer, the identification recoils and their subsequent decay modes (alpha-, fission-, and gamma-ray decay) have been studied. The JUROGAM gamma-ray array of 43 Compton-suppressed HPGe detectors has been employed in the in-beam spectroscopy of the trans-fermium region. In-beam gamma-ray spectroscopy studies of trans-fermium nuclei 253 No, 254 No, 250 Fm, 251 Md, 253 No and 255 Lr have been performed, as well as detailed focal plane spectroscopy. Selected highlights of the work will be presented

Induction of micronuclei by 2-hydroxypyridine in water and elimination of solution genotoxicity by UVC (254 nm) photolysis

International Nuclear Information System (INIS)

Skoutelis, Charalambos G.; Vlastos, Dimitris; Kortsinidou, Marianna C.; Theodoridis, Ioannis T.; Papadaki, Maria I.

2011-01-01

Highlights: ► 2-Hydroxypyridine (2-HPY) is the major metabolite of 2-halogenated pyridines photolysis. ► We examine the genotoxicity of 2-HPY in cultured human lymphocytes applying the micronucleus assay. ► 2-HPY was found to be genotoxic. ► Aqueous solutions of 2-HPY were irradiated by UV at 254 nm. ► Solution genotoxicity can be completely removed after prolonged phototreatment. - Abstract: 2-Hydroxypyridine (2-HPY) is a major first-stage product formed upon the photolytic destruction of 2-halogenated pyridines. Genotoxicity of 2-HPY in water was studied as a function of concentration. Aqueous solutions of 2-HPY were irradiated by ultraviolet (UV) at 254 nm. 2-HPY concentration, solution total organic carbon (TOC) concentration and solution genotoxicity were measured as a function of treatment time and their profile as a function of time is presented in this work. 2-HPY was found to be genotoxic at all concentrations in the range of 5–400 μg ml −1 . 2-HPY mineralises completely upon prolonged UV irradiation. All untreated and irradiated solution samples, taken at different photo-treatment times, were tested in cultured human lymphocytes applying the cytokinesis block micronucleus (CBMN) assay. The genotoxicity of the solution was reduced near to the control level after prolonged UV irradiation.
c-Abl phosphorylation of Yin Yang 1's conserved tyrosine 254 in the spacer region modulates its transcriptional activity.

Science.gov (United States)

Daraiseh, Susan I; Kassardjian, Ari; Alexander, Karen E; Rizkallah, Raed; Hurt, Myra M

2018-05-25

Yin Yang 1 (YY1) is a multifunctional transcription factor that can activate or repress transcription depending on the promotor and/or the co-factors recruited. YY1 is phosphorylated in various signaling pathways and is critical for different biological functions including embryogenesis, apoptosis, proliferation, cell-cycle regulation and tumorigenesis. Here we report that YY1 is a substrate for c-Abl kinase phosphorylation at conserved residue Y254 in the spacer region. Pharmacological inhibition of c-Abl kinase by imatinib, nilotinib and GZD824, knock-down of c-Abl using siRNA, and the use of c-Abl kinase-dead drastically reduces tyrosine phosphorylation of YY1. Both radioactive and non-radioactive in vitro kinase assays, as well as co-immunoprecipitation in different cell lines, show that the target of c-Abl phosphorylation is tyrosine residue 254. c-Abl phosphorylation has little effect on YY1 DNA binding ability or cellular localization in asynchronous cells. However, functional studies reveal that c-Abl mediated phosphorylation of YY1 regulates YY1's transcriptional ability in vivo. In conclusion, we demonstrate the novel role of c-Abl kinase in regulation of YY1's transcriptional activity, linking YY1 regulation with c-Abl tyrosine kinase signaling pathways. Copyright © 2018. Published by Elsevier B.V.
Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source; Determinacao de manganes em minerios, por analise por ativacao, usando californio-252 como fonte de neutrons

Energy Technology Data Exchange (ETDEWEB)

Cardoso, Antonio

1976-07-01

Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction {sup 55}Mn (n.gamma){sup 56} Mn, high concentration of manganese in the matrix and short half - life of {sup 56}Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions {sup 56}Fe(n,p){sup 56}Mn and {sup 59} Co (n, {alpha}){sup 56} were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)
Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source; Determinacao de manganes em minerios, por analise por ativacao, usando californio-252 como fonte de neutrons

Energy Technology Data Exchange (ETDEWEB)

Cardoso, Antonio

1976-07-01

Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction {sup 55}Mn (n.gamma){sup 56} Mn, high concentration of manganese in the matrix and short half - life of {sup 56}Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions {sup 56}Fe(n,p){sup 56}Mn and {sup 59} Co (n, {alpha}){sup 56} were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)
Source storage and transfer cask: Users Guide

International Nuclear Information System (INIS)

Eccleston, G.W.; Speir, L.G.; Garcia, D.C.

1985-04-01

The storage and shield cask for the dual californium source is designed to shield and transport up to 3.7 mg (2 Ci) of 252 Cf. the cask meets Department of Transportation (DOT) license requirements for Type A materials (DOT-7A). The cask is designed to transfer sources to and from the Flourinel and Fuel Storage (FAST) facility delayed-neutron interrogator. Californium sources placed in the cask must be encapsulated in the SR-CF-100 package and attached to Teleflex cables. The cask contains two source locations. Each location contains a gear box that allows a Teleflex cable to be remotely moved by a hand crank into and out of the cask. This transfer procedure permits sources to be easily removed and inserted into the delayed-neutron interrogator and reduces personnel radiation exposure during transfer. The radiation dose rate with the maximum allowable quantity of californium (3.7 mg) in the cask is 30 mR/h at the surface and less than 2 mR/h 1 m from the cask surface. This manual contains information about the cask, californium sources, describes the method to ship the cask, and how to insert and remove sources from the cask. 28 figs
Radionuclides in rodents

International Nuclear Information System (INIS)

Taylor, G.N.

1985-01-01

Studies are being conducted in mice comparing the toxicity of radium-226, plutonium-239, americium-241, californium-249 and californium-252 in C57B1/Do (albino) mice and the toxicity of americium-241, plutonium-239 and radium-226 in deer mice (Peromyscus maniculatus) and grasshopper mice (Onychomys leucogaster). These experiments will ultimately enable comparison of the toxicity of the above actinide toxicity in man to be made using radium toxicity as the baseline
Kinetics and mechanism investigation on the destruction of oxytetracycline by UV-254 nm activation of persulfate

Energy Technology Data Exchange (ETDEWEB)

Liu, Yiqing [Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756 (China); Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); He, Xuexiang [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); Fu, Yongsheng [Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756 (China); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States)

2016-03-15

Highlights: • The most effective destruction of OTC by UV/PS was achieved at near neutral pH. • Deprotonated HOTC{sup −} had the highest second-order rate constant with SO{sub 4}·{sup −}. • Presence of HCO{sub 3}{sup −} or Cu{sup 2+} enhanced the removal of OTC in UV/PS system. • Total organic carbon was degraded slowly during the mineralization of OTC. • Studies on the degradation mechanism revealed four different reaction pathways. - Abstract: Oxytetracycline (OTC), an important broad-spectrum antibiotic, has been detected extensively in various environmental systems, which may have a detrimental impact on ecosystem and human health through the development of drug resistant bacteria and pathogens. In this study, the degradation of OTC was evaluated by UV-254 nm activated persulfate (PS). The observed UV fluence based pseudo first-order rate constant (k{sub obs}) was found to be the highest at near neutral pH conditions (pH 5.5–8.5). Presence of various natural water constituents had different effects on OTC degradation, with a significant enhancement in the presence of bicarbonate or Cu{sup 2+}. Limited elimination of total organic carbon (TOC) and PS was observed during the mineralization of OTC. Transformation byproducts in the presence and absence of hydroxyl radical scavenging agent tert-butanol (t-BuOH) were identified using ultra-high definition accurate-mass quadrupole time-of-flight liquid chromatography/mass spectrometer (LC-QTOF/MS). Potential OTC degradation mechanism was subsequently proposed revealing four different reaction pathways by SO{sub 4}·{sup −} reaction including hydroxylation (+16 Da), demethylation (−14 Da), decarbonylation (−28 Da) and dehydration (−18 Da). This study suggests that UV-254 nm/PS is a promising treatment technology for the control of water pollution caused by emerging contaminants such as OTC.
Kinetics and mechanism investigation on the destruction of oxytetracycline by UV-254 nm activation of persulfate

International Nuclear Information System (INIS)

Liu, Yiqing; He, Xuexiang; Fu, Yongsheng; Dionysiou, Dionysios D.

2016-01-01

Highlights: • The most effective destruction of OTC by UV/PS was achieved at near neutral pH. • Deprotonated HOTC"− had the highest second-order rate constant with SO_4·"−. • Presence of HCO_3"− or Cu"2"+ enhanced the removal of OTC in UV/PS system. • Total organic carbon was degraded slowly during the mineralization of OTC. • Studies on the degradation mechanism revealed four different reaction pathways. - Abstract: Oxytetracycline (OTC), an important broad-spectrum antibiotic, has been detected extensively in various environmental systems, which may have a detrimental impact on ecosystem and human health through the development of drug resistant bacteria and pathogens. In this study, the degradation of OTC was evaluated by UV-254 nm activated persulfate (PS). The observed UV fluence based pseudo first-order rate constant (k_o_b_s) was found to be the highest at near neutral pH conditions (pH 5.5–8.5). Presence of various natural water constituents had different effects on OTC degradation, with a significant enhancement in the presence of bicarbonate or Cu"2"+. Limited elimination of total organic carbon (TOC) and PS was observed during the mineralization of OTC. Transformation byproducts in the presence and absence of hydroxyl radical scavenging agent tert-butanol (t-BuOH) were identified using ultra-high definition accurate-mass quadrupole time-of-flight liquid chromatography/mass spectrometer (LC-QTOF/MS). Potential OTC degradation mechanism was subsequently proposed revealing four different reaction pathways by SO_4·"− reaction including hydroxylation (+16 Da), demethylation (−14 Da), decarbonylation (−28 Da) and dehydration (−18 Da). This study suggests that UV-254 nm/PS is a promising treatment technology for the control of water pollution caused by emerging contaminants such as OTC.
Cold valleys in the radioactive decay of 248-254Cf isotopes

International Nuclear Information System (INIS)

Biju, R.K.; Sahadevan, Sabina; Santhosh, K.P.; Joseph, Antony

2008-01-01

Based on the concept of cold valley in cold fission and fusion, we have investigated the cluster decay process in 248-254 Cf isotopes. In addition to alpha particle minima, other deep minima occur for S, Ar and Ca clusters. It is found that inclusion of proximity potential does not change the position of minima but minima become deeper. Taking Coulomb and proximity potential as interacting barrier for post-scission region, we computed half-lives and other characteristics for various clusters from these parents. Our study reveals that these parents are stable against light clusters and unstable against heavy clusters. Computed half-lives for alpha decay agree with experimental values within two orders of magnitude. The most probable clusters from these parents are predicted to be 46 Ar, 48,50 Ca which indicate the role of doubly or near doubly magic clusters in cluster radioactivity. Odd A clusters are found to be favorable for emission from odd A parents. Cluster decay model is extended to symmetric region and it is found that symmetric fission is also probable which stresses the role of doubly or near doubly magic 132 Sn nuclei. Geiger-Nuttal plots were studied for various clusters and are found to be linear with varying slopes and intercepts. (author)
Clofibric acid degradation in UV254/H2O2 process: effect of temperature.

Science.gov (United States)

Li, Wenzhen; Lu, Shuguang; Qiu, Zhaofu; Lin, Kuangfei

2010-04-15

The degradation of clofibric acid (CA) in UV(254)/H(2)O(2) process under three temperature ranges, i.e. T1 (9.0-11.5 degrees C), T2 (19.0-21.0 degrees C) and T3 (29.0-30.0 degrees C) was investigated. The effects of solution constituents including NO(3)(-) and HCO(3)(-) anions, and humic acid (HA) on CA degradation were evaluated in Milli-Q waters. CA degradation behaviors were simulated with the pseudo-first-order kinetic model and the apparent rate constant (k(ap)) and half-life time (t(1/2)) were calculated. The results showed that higher temperature would favor CA degradation, and CA degradation was taken place mostly by indirect oxidation through the formation of OH radicals in UV(254)/H(2)O(2) process. In addition, the effects of both NO(3)(-) and HCO(3)(-) anions at two selected concentrations (1.0x10(-3) and 0.1 mol L(-1)) and HA (20 mg L(-1)) on CA degradation were investigated. The results showed that HA had negative effect on CA degradation, and this effect was much more apparent under low temperature condition. On the other hand, the inhibitive effect on CA degradation at both lower and higher concentrations of bicarbonate was observed, and this inhibitive effect was much more apparent at higher bicarbonate concentration and lower temperature condition. While, at higher nitrate concentration the inhibitive effect on CA degradation under three temperature ranges was observed, and with the temperature increase this negative effect was apparently weakened. However, at lower nitrate concentration a slightly positive effect on CA degradation was found under T2 and T3 conditions. Moreover, when using a real wastewater treatment plant (WWTP) effluent spiked with CA over 99% of CA removal could be achieved under 30 degrees C within only 15 min compared with 40 and 80 min under 20 and 10 degrees C respectively, suggesting a significant promotion in CA degradation under higher temperature condition. Therefore, it can be concluded that temperature plays an
Quantum-chemical consideration of extermal valent forms of actinides

International Nuclear Information System (INIS)

Ionova, G.V.; Pershina, V.G.; Spitsyn, V.I.

1982-01-01

Stability of valent forms of actinides that has not yet studied experimentally, is considered within the framework of quantum-chemical considerations. Oxidizing potentials E 0 for actinide elements are determined theoretically. A dependence of the definite valent state stability on relativistic effect is shown. A conclusion is made that oxidizing potential E 0 (4-5) for americium should be higher than E 0 (4-5) for plutonium. A relatively small oxidizing potential E 0 (4-5) for curium speaks about principle possibility of production of five-valent curium in solution, though it is less stable than the six-valent one. Oxidizing potential corresponding to transition of three-valent californium into the four-valent state should be less than the value adopted in literature. A relatively small oxidizing potential of californium E 0 (4-5) speaks about possible existence of five-valent californium in solution
Design of a homogeneous subcritical nuclear reactor based on thorium with a source of californium 252; Diseno de un reactor nuclear subcritico homogeneo a base de Torio con una fuente de Californio 252

Energy Technology Data Exchange (ETDEWEB)

Delgado H, C. E.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico); Sajo B, L., E-mail: ce_delgado89@hotmail.com [Universidad Simon Bolivar, Laboratorio de Fisica Nuclear, Apdo. 89000, 1080A Caracas (Venezuela, Bolivarian Republic of)

2015-10-15

Full text: One of the energy alternatives to fossil fuels which do not produce greenhouse gases is the nuclear energy. One of the drawbacks of this alternative is the generation of radioactive wastes of long half-life and its relation to the generation of nuclear materials to produce weapons of mass destruction. An option to these drawbacks of nuclear energy is to use Thorium as part of the nuclear fuel which it becomes in U{sup 233} when capturing neutrons, that is a fissile material. In this paper Monte Carlo methods were used to design a homogeneous subcritical reactor based on thorium. As neutron reflector graphite was used. The reactor core is homogeneous and is formed of 70% light water as moderator, 12% of enriched uranium UO{sub 2}(NO{sub 3}){sub 4} and 18% of thorium Th(NO{sub 3}){sub 4} as fuel. To start the nuclear fission chain reaction an isotopic source of californium 252 was used with an intensity of 4.6 x 10{sup 7} s{sup -1}. In the design the value of the effective multiplication factor, whose value turned out k{sub eff} <1 was calculated. Also, the neutron spectra at different distances from the source and the total fluence were calculated, as well as the values of the ambient dose equivalent in the periphery of the reactor. (Author)
48 CFR 15.403-4 - Requiring certified cost or pricing data (10 U.S.C. 2306a and 41 U.S.C. 254b).

Science.gov (United States)

2010-10-01

... or pricing data (10 U.S.C. 2306a and 41 U.S.C. 254b). 15.403-4 Section 15.403-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.403-4 Requiring certified cost or pricing data (10 U.S.C. 2306a and 41 U.S.C...
Radiochemical search for neutron-rich isotopes of nielsbohrium in the (16)O + (254)Es reaction

International Nuclear Information System (INIS)

Schaedel, M.; Jaeger, E.; Bruechle, W.; Suemmerer, K.; Hulet, E.K.; Wild, J.F.; Lougheed, R.W.; Dougan, R.J.; Moody, K.J.

1994-09-01

We have used on-line gas chromatography to search for new isotopes of element 107 near the deformed sub-shell at N = 162 and Z = 108. Enhanced nuclear stability is predicted for this region. 254g Es was irradiated with 16 O at barrier energies to minimize the fusion hindrance in the entrance channel and to reduce the excitation energy of the compound nucleus to a minimum value. For half-lives between roughly two seconds and two minutes no signal for a positive identification of a new isotope of element 107 was detected. Consequently, only an upper cross-section limit of a few nanobarns was obtained. While this cross-section limit was too high to probe the influence of the predicted enhanced nuclear ground-state stability on the survival probability in the fission/evaporation competition, a very large cross-section enhancement would have been detectable. (orig.)
A prospective study on time to recovery in 254 injured novice runners.

Directory of Open Access Journals (Sweden)

Rasmus Oestergaard Nielsen

Full Text Available Describe the diagnoses and the time to recovery of running-related injuries in novice runners.Prospective cohort study on injured runners.This paper is a secondary data analysis of a 933-person cohort study (DANO-RUN aimed at characterizing risk factors for injury in novice runners. Among those sustaining running-related injuries, the types of injuries and time to recovery is described in the present paper. All injured runners were diagnosed after a thorough clinical examination and then followed prospectively during their recovery. If they recovered completely from injury, time to recovery of each injury was registered.A total of 254 runners were injured. The proportion of runners diagnosed with medial tibial stress syndrome was 15%, 10% for patellofemoral pain, 9% for medial meniscal injury, 7% for Achilles tendinopathy and 5% for plantar fasciitis. Among the 220 runners (87% recovering from their injury, the median time to recovery was 71 days (minimum = 9 days, maximum = 617 days.Medial tibial stress syndrome was the most common injury followed by patellofemoral pain, medial meniscal injury and Achilles tendinopathy. Half of the injured runners were unable to run 2×500 meters without pain after 10 weeks. Almost 5% of the injured runners received surgical treatment.
Critical pitting temperature for Type 254 SMO stainless steel in chloride solutions

International Nuclear Information System (INIS)

Abd El Meguid, E.A.; Abd El Latif, A.A.

2007-01-01

The variation with time of the open circuit potential of high molybdenum containing stainless steel (Type 254 SMO) was measured in 4% sodium chloride solution in the temperatures range 30-100 deg. C. The plot of steady state potentials as function of temperature showed an inflection at 50 deg. C, attributed to the decrease of oxygen solubility in test solution above 50 deg. C. Potentiodynamic cycling anodic polarization technique was used to determine the critical pitting potential (E pit ) and the critical protection potential (E prot ) of the steel in 4-30% NaCl solutions at temperatures between 30 and 100 deg. C. By plotting the two values versus solution temperature, the corresponding critical pitting (CPT) and the critical protection (CPrT) temperatures were determined. Both parameters decreased with increasing chloride content. Above the CPT, E pit and E prot decreased linearly with log[Cl - ]. The addition of bromide ions to the solution shifted both E pit and E prot towards positive values. In 4% NaCl, E pit increased linearly with pH in the range 1-10. The combined effect of chloride ion concentration and pH on the morphology of the pits was examined by scanning electron microscopy (SEM) following potentiodynamic cycling anodic polarization
Determination of the total mercury in contaminated soils by direct solid sampling atomic absorption spectrometry using an AMA-254 device and radiochemical neutron activation analysis

Czech Academy of Sciences Publication Activity Database

Sysalová, J.; Kučera, Jan; Fikrle, Marek; Drtinová, B.

2013-01-01

Roč. 110, SEP (2013), s. 691-694 ISSN 0026-265X R&D Projects: GA ČR GAP503/12/0682; GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:61389005 Keywords : Mercury * contaminated soils * AMA-254 * RNAA Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.583, year: 2013
Photochemical Degradation of the Anticancer Drug Bortezomib by V-UV/UV (185/254 nm) Investigated by (1)H NMR Fingerprinting: A Way to Follow Aromaticity Evolution.

Science.gov (United States)

Martignac, Marion; Balayssac, Stéphane; Gilard, Véronique; Benoit-Marquié, Florence

2015-06-18

We have investigated the removal of bortezomib, an anticancer drug prescribed in multiple myeloma, using the photochemical advanced oxidation process of V-UV/UV (185/254 nm). We used two complementary analytical techniques to follow the removal rate of bortezomib. Nuclear magnetic resonance (NMR) is a nonselective method requiring no prior knowledge of the structures of the byproducts and permits us to provide a spectral signature (fingerprinting approach). This untargeted method provides clues to the molecular structure changes and information on the degradation of the parent drug during the irradiation process. This holistic NMR approach could provide information for monitoring aromaticity evolution. We use liquid chromatography, coupled with high-resolution mass spectrometry (LC-MS), to correlate results obtained by (1)H NMR and for accurate identification of the byproducts, in order to understand the mechanistic degradation pathways of bortezomib. The results show that primary byproducts come from photoassisted deboronation of bortezomib at 254 nm. A secondary byproduct of pyrazinecarboxamide was also identified. We obtained a reliable correlation between these two analytical techniques.
Closure Report for Corrective Action Unit 254: Area 25, R-MAD Decontamination Facility, Nevada Test Site, Nevada

Energy Technology Data Exchange (ETDEWEB)

G. N. Doyle

2002-02-01

Corrective Action Unit (CAU) 254 is located in Area 25 of the Nevada Test Site (NTS), approximately 100 kilometers (km) (62 miles) northwest of Las Vegas, Nevada. The site is located within the Reactor Maintenance, Assembly and Disassembly (R-MAD) compound and consists of Building 3126, two outdoor decontamination pads, and surrounding areas within an existing fenced area measuring approximately 50 x 37 meters (160 x 120 feet). The site was used from the early 1960s to the early 1970s as part of the Nuclear Rocket Development Station program to decontaminate test-car hardware and tooling. The site was reactivated in the early 1980s to decontaminate a radiologically contaminated military tank. This Closure Report (CR) describes the closure activities performed to allow un-restricted release of the R-MAD Decontamination Facility.
Comparative ultraviolet action spectra (254-320 nm) of five wild-type eukaryotic microorganisms and Escherichia coli

International Nuclear Information System (INIS)

Calkins, J.; Wheeler, J.S.; Keller, C.I.; Colley, E.; Hazle, J.D.

1988-01-01

The action spectra of five eukaryotic organisms and the prokaryote, Escherichia coli, were examined over the wavelength range, 254-320 nm. Both the repair competent and three repair defective strains (E. coli, Caenorhabditis elegans, Saccharomyces) were examined. Tetrahymena pyriformis action spectra were performed with and without the excision repair inhibitor caffeine present. Others have observed that lethality, mutation, and the production of pyrimidine dimers show much the same wavelength dependence as DNA absorption. The results presented here demonstrate several action spectra which deviate from the DNA absorption spectra. Ultraviolet sensitization ratios (repair competent/repair defective) were also examined and were shown to change over the wavelength range. These findings suggest that DNA may not be the only important chromophore leading to cell death in the uv wavelength range studied. Since uv-B is of major importance in solar uv damage, these findings may also yield important implications for solar uv studies

Lethal effect of short-wave (254 nm) UV-radiation on cells of Chlamidomonas reinhardii strains with different carotenoid content

International Nuclear Information System (INIS)

Kamchatova, I.E.; Chunaev, A.S.; Bronnikov, V.A.

1987-01-01

In experiments on related Chlamidomonas reinhardii strains of similar mating type a study was made of sensitivity of cells with different carotenoid content to UV-radiation of 254 nm. Mutants having a lower, as opposed to the wild type strain, content of carotenoids exhibited an increased radiosensitivity. A carotenoid-free mutant was found to possess a higher sensitivity to UV-radiation which was typical of the strain with the impaired excision repair system. The studied subclone of the UV-radiosensitive strain CC-888 was unable to photoreactivate the UV-induced damages which was typical of the wild-type strain. The content of carotenoids in cells of this subnuclone exceeded that in cells of mutants with the reduced pigmentation
Projecto 254 - Produção de suínos ao ar livre : unidade de demonstração Programa AGRO

OpenAIRE

Marinho, M.C.; Dias, S.F.; Rodrigues, J.P.V.

2006-01-01

A produção de suínos ao ar livre pode contribuir para a preservação e valorização das raças autóctones e dos produtos delas derivados, evitando assim a sua extinção. O projecto, Produção de suínos ao ar livre – Unidade de demonstração, cujo período de execução vai de setembro de 2004 a dezembro de 2006, tem como principal objectivo demonstrar a tecnologia de produção de leitões ao ar livre. Programa AGRO - Projecto 254, Medida 8.1.
Atomic gas temperature in a nonequilibrium high-intensity discharge lamp determined from the red wing of the resonance mercury line 254 nm

International Nuclear Information System (INIS)

Drakakis, E.; Karabourniotis, D.

2012-01-01

For developing low-wattage high intensity discharge (HID) lamps, a better understanding of the relatively unexplored nonequilibrium phenomena is essential. This needs interpretation of diagnostic results by methods free from equilibrium assumptions. In this paper, the atomic temperature is determined from the simulation of a quasistatic broadened resonance line by distinguishing between atomic temperature and excitation temperature in the equation of radiative transfer. The proposed method is applied to the red wing of the resonance mercury line 254 nm emitted from a HID lamp working on ac. The experimental results show severe deviation from local thermodynamic equilibrium. More than one thousand degrees difference was obtained between atomic and electron temperatures at the maximum current phase.
Atomic gas temperature in a nonequilibrium high-intensity discharge lamp determined from the red wing of the resonance mercury line 254 nm

Energy Technology Data Exchange (ETDEWEB)

Drakakis, E. [Technological Educational Institute, Department of Electrical Engineering, 71004 Heraklion (Greece); Karabourniotis, D. [Institute of Plasma Physics, Department of Physics, University of Crete, 71003 Heraklion (Greece)

2012-09-01

For developing low-wattage high intensity discharge (HID) lamps, a better understanding of the relatively unexplored nonequilibrium phenomena is essential. This needs interpretation of diagnostic results by methods free from equilibrium assumptions. In this paper, the atomic temperature is determined from the simulation of a quasistatic broadened resonance line by distinguishing between atomic temperature and excitation temperature in the equation of radiative transfer. The proposed method is applied to the red wing of the resonance mercury line 254 nm emitted from a HID lamp working on ac. The experimental results show severe deviation from local thermodynamic equilibrium. More than one thousand degrees difference was obtained between atomic and electron temperatures at the maximum current phase.
Corrective Action Decision Document for Corrective Action Unit 254: Area 25 R-MAD Decontamination Facility, Nevada Test Site, Nevada

International Nuclear Information System (INIS)

2000-01-01

This Corrective Action Decision Document identifies and rationalizes the US Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 254, R-MAD Decontamination Facility, under the Federal Facility Agreement and Consent Order. Located in Area 25 at the Nevada Test Site in Nevada, CAU 254 is comprised of Corrective Action Site (CAS) 25-23-06, Decontamination Facility. A corrective action investigation for this CAS as conducted in January 2000 as set forth in the related Corrective Action Investigation Plan. Samples were collected from various media throughout the CAS and sent to an off-site laboratory for analysis. The laboratory results indicated the following: radiation dose rates inside the Decontamination Facility, Building 3126, and in the storage yard exceeded the average general dose rate; scanning and static total surface contamination surveys indicated that portions of the locker and shower room floor, decontamination bay floor, loft floor, east and west decon pads, north and south decontamination bay interior walls, exterior west and south walls, and loft walls were above preliminary action levels (PALs). The investigation-derived contaminants of concern (COCs) included: polychlorinated biphenyls, radionuclides (strontium-90, niobium-94, cesium-137, uranium-234 and -235), total volatile and semivolatile organic compounds, total petroleum hydrocarbons, and total Resource Conservation and Recovery Act (Metals). During the investigation, two corrective action objectives (CAOs) were identified to prevent or mitigate human exposure to COCs. Based on these CAOs, a review of existing data, future use, and current operations at the Nevada Test Site, three CAAs were developed for consideration: Alternative 1 - No Further Action; Alternative 2 - Unrestricted Release Decontamination and Verification Survey; and Alternative 3 - Unrestricted
Oxidation-reduction properties of americium, curium, berkelium, californium, einsteinium and fermium, and thermodynamic consequences for the 5f series

International Nuclear Information System (INIS)

Samhoun, K.

1976-01-01

The amalgamation of 5f elements from Am to Fm has been studied by using 241 Am, 244 Cm, 249 Bk, 249 Cf, 252 Cf, 253 Es, 254 Es, 252 Fm and 255 Fm with two electrochemical methods, radiocoulometry and radiopolarography, perfectly adapted to investigate extremely diluted solutions when the concentration of electroactive species is as low as 10 -16 M. The theory of radiocoulometry has been developed in the general cases of reversible and irreversible electrode process. It has been used to interpret the experimental data on the kinetic curves of amalgamation, and to estimate the standard rate constant of the electrode process in complexing medium (citric). On the other hand the radiopolarographic method has been applied to study the mechanism of reduction at the dropping mercury electrode of cations M 3+ in aqueous medium to the metal M with formation of amalgam. The results are exploited into two directions: 1- Acquisition of some data concerning the oxidation-reduction properties of elements from Am to Fm. Therefore the standard electrode E 0 [M(III-0)] potentials for Bk, Cf and Es, and the standard electrode E 0 [M(II-0)] potential for Fm are estimated and the relative stability of each oxidation state (from II to VII) of 5f elements is discussed; 2- Acquisition of unknown thermodynamic data on transcalifornium elements. Correlations between 4f and 5f elements are precised and some divergences appear for the second half of 4f and 5f series (i.e. for 65 [fr
ONKALO pose experiment. Geophysical logging and imaging of drillholes ONK-PP223, ONK-PP226, ONK-PP254 and ONK-PP259...261

International Nuclear Information System (INIS)

Tarvainen, A.-M.

2011-08-01

Suomen Malmi Oy conducted geophysical drillhole logging as well as optical and acoustic imaging of shallow drillholes ONK-PP223, ONK-PP226, ONK-PP254, ONKPP259, ONK-PP260 and ONK-PP261 at ONKALO in the investigation niche ONKTKU- 3 (POSE) between December 2009 and June 2010. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and data processing. The report describes field operation, equipment as well as processing procedures and shows the obtained results and an analysis of their quality in the appendices. The raw and processed data are delivered digitally in WellCAD, PDF and Excel format. (orig.)
Definitive Brachytherapy for Kaposi's Sarcoma

International Nuclear Information System (INIS)

Williams, A.; Ezzell, G.; Zalupski, M.; Fontanesi, J.

1996-01-01

Purpose: To assess the efficacy and possible complications in patients diagnosed with Kaposi's sarcoma and treated with definitive brachytherapy. Methods and Materials: Between January, 1995 and December, 1995, four patients with Kaposi's sarcoma (KS) were treated with brachytherapy. Three patients, all with positive HIV status were treated using Iridium 192 (Ir-192) sources via a high-dose rate remote afterloader. One patient with endemic KS was treated using the application of catheters loaded with Californium 252. Eight sites were treated and included scalp, feet, nose, penis, hand, neck, and back. Dose rate for Ir-192 was 330cGy/fx to a total dose of 990cGy. The Californium was delivered as 100nGy/b.i.d. to a total dose of 900nGy. Follow-up as ranged from 2-6 months. Results: All four patients remain alive. Seven of eight sites have had complete clinical response and each patient has reported durable pain relief that has not subsided through last follow-up of 1/96. Two of eight sites, both treated with surface mold technique with Californium 252 developed moist desquamation. The remaining six sites did not demonstrate significant toxicity. Conclusion: Brachytherapy can offer Kaposi's sarcoma patients results that are equivalent to external beam radiation therapy, with minimal complications, a shorter treatment time and potential cost effectiveness
Californium Recovery from Palladium Wire

Energy Technology Data Exchange (ETDEWEB)

Burns, Jon D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-08-01

The recovery of ²⁵²Cf from palladium-²⁵²Cf cermet wires was investigated to determine the feasibility of implementing it into the cermet wire production operation at Oak Ridge National Laboratory’s Radiochemical Engineering Development Center. The dissolution of Pd wire in 8 M HNO₃ and trace amounts of HCl was studied at both ambient and elevated temperatures. These studies showed that it took days to dissolve the wire at ambient temperature and only 2 hours at 60°C. Adjusting the ratio of the volume of solvent to the mass of the wire segment showed little change in the kinetics of dissolution, which ranged from 0.176 mL/mg down to 0.019 mL/mg. A successful chromatographic separation of ¹⁵³Gd, a surrogate for ²⁵²Cf, from Pd was demonstrated using AG 50x8 cation exchange resin with a bed volume of 0.5 mL and an internal diameter of 0.8 cm.
Californium-252 Program Equipment Evaluation

Energy Technology Data Exchange (ETDEWEB)

Chattin, Fred Rhea [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wilson, Kenton [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ezold, Julie G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-12-01

To successfully continue the ²⁵²Cf production and meet the needs of the customers, a comprehensive evaluation of the Building 7920 processing equipment was requested to identify equipment critical to the operational continuity of the program.
The Effects of Short Wave UV Irradiation (254-366nm on Color Values of Recycled and Bleached ONP/OMP Pulps

Directory of Open Access Journals (Sweden)

Emrah Peşman

2011-04-01

Full Text Available ABSTRACT As it is known, mechanical pulp papers include significant amount of lignin and carbohydrates as well as cellulose. Thus, when these lignin reach papers irradiated with short wave UV light they could not protect their color. In this study, bleaching of ONP/OMG recycled pulps with hydrogen peroxide, sodium percarbonate, sodium dithyonite, sodium borohydride and formamidin sulfunic acid were performed. Then the test papers of these pulps were irradiated with 254-366nm UV light and changes in the ISO Brightness, CIE L*a*b*, yellowness (YI and whiteness (WI values were observed. At the result of study, all bleaching agents were determined as insufficient in the respect of color stability. But if they compared with each other, the two stages sodium percarbonate-sodium borohydride bleaching sequence was gave the best results against to color reversion. Keywords: Old news/old magazine papers (ONP/OMG, Bleaching, Color Stability, UV Irradiation
Low-energy fission systematics of the fermium isotopes: the transition from mass asymmetry at fermium-254 to symmetry at fermium-259

International Nuclear Information System (INIS)

Hoffman, D.C.

1976-01-01

Recent measurements have shown that 259 Fm gives the highest total kinetic energy release and the most symmetric mass division so far observed for spontaneous fission. These results continue the trends observed previously in the fermium isotopes toward higher total kinetic energies and more symmetric mass division with increasing mass of the fermium isotopes. The transition from asymmetric mass division ( 254 Fm) to highly favored symmetric mass division ( 259 Fm) now appears to have been completed. These features are consistent with the simple postulate that the more neutron-rich fermium isotopes show an increase in the yield of symmetric fragments and in the total kinetic energy because symmetric mass division of fermium (Z = 100) nuclei results in two fragments which have the magic proton number of 50 and are close to the magic neutron number of 82. The proximity of the fragments to the doubly magic configuration seems to have a profound effect on the mass division and total kinetic energy release in fission
Damage to uracil- and adenine-containing bases, nucleosides, nucleotides and polynucleotides: quantum yields on irradiation at 193 and 254 nm

International Nuclear Information System (INIS)

Gurzadyan, G.G.; Goerner, H.

1994-01-01

Photoreactions, such as base release and decomposition of the base moeity, induced by either 20 ns laser pulses at 193 nm or continuous 254 nm irradiation, were studied for a series of uracil and adenine derivatives in neutral aqueous solution. The quantum yield of chromophore loss (Φ cl ) depends significantly on the nature of the nucleic acid constituent and the saturating gas (Ar, N 2 O or O 2 ). In the case of polynucleotides the destruction of nucleotides was measured by high-performance liquid chromatography after hydrolysis; the quantum yields (Φ dn ) are comparable to those of chromophore loss or larger. The Φ cl and Φ dn of 0.04-0.1 for poly(U) and poly(dU), obtained for both wavelengths of irradiation, are due to processes originating from the lowest excited singlet state, i.e. formation of photohydrates and photodimers, and a second part from photoionization using λ irr = 193 nm. Irradiation at 193 nm effectively splits pyrimidine dimers and thus reverts them into monomers. (author)
Synthesis and antimicrobial screening of novel 2-(5-(4-(allyloxy-3-methoxyphenyl-1H-pyrazol-3-ylphenols analogues of 2-(4-(allyloxy-3-methoxyphenyl-4H-chromen-4-ones

Directory of Open Access Journals (Sweden)

Asha V. Chate

2012-01-01

Full Text Available A series of novel 2-(5-(4-(allyloxy-3-methoxyphenyl-1H-pyrazol-3-ylphenols derivatives have been synthesized via the ring opening of 2-(4-(allyloxy-3-methoxyphenyl-4H-chromen-4-ones in ethanol and hydrazine hydrate under reflux condition. The synthesized compounds were screened for antibacterial and antifungal activity against bacteria Staphylococcus aureus (MRSA E710 and Escherichia coli (ATCC 25922 and fungi Candida albicans and Aspergillus fumigates respectively. Some of the tested compounds showed significant antimicrobial activity. 1H NMR, IR, Mass spectral data and elemental analysis elucidated the structures of the all newly synthesized compounds.
Californium Cf-252 for pelvic radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Maruyama, Y; Feola, J M; Tai, D; Wilson, L C; Van Nagell, J R; Yoneda, J

1978-01-01

Clinical data about therapy concerning tumors of the female gynecological cancers of the cervix, vagina and uterus are reviewed. Dosimetric, laboratory and radiobiological research data form the basis for an approach to such tumors using Cf-252 as a form of boost brachytherapy. Extreme personnel hazards are a real and important consideration and indicate that maximal containment and isolation procedures should be exercised in its use.
International travel in the immunocompromised patient: a cross-sectional survey of travel advice in 254 consecutive patients.

Science.gov (United States)

Bialy, C; Horne, K; Dendle, C; Kanellis, J; Littlejohn, G; Ratnam, I; Woolley, I

2015-06-01

Our primary aim was to determine the rate of overseas travel in immunocompromised individuals attending appropriate clinics at an Australian tertiary care hospital. We also aimed to characterise health-seeking behaviour prior to travel and investigated sources of pre-travel advice, compared travel patterns and activities between three specific immunosuppressed groups, and examined pre-immunosuppression patient serology. We implemented a cross-sectional survey of patients between February and August 2012. This survey was implemented among three outpatient populations at Monash Medical Centre, an Australian tertiary care hospital. We recruited 254 immunosuppressed adults from three patient populations: human immunodeficiency virus-positive individuals, renal transplant patients and rheumatology patients requiring immunosuppressive therapy. No clinical intervention was performed. In the 10 years preceding the survey, 153 (60.2%) participants reported international travel. Of these, 105 (68.6%) were immunosuppressed at the time of travel. These patients were 47.6% male and 60% Australian born. Forty per cent were visiting friends and relatives as part of their travel. Fifty-four per cent of those immunocompromised at the time of travel were going to high-risk destinations. Pathology files indicated that serological screening was frequently not performed prior to immunosuppression in the renal transplant and rheumatology groups. Immunocompromised patients often travel to high-risk destinations with limited or inadequate pre-travel preparations. Doctors caring for the immunocompromised should be aware of travel risks, suitable vaccination protocols and when to refer to specialist travel clinics. © 2015 Royal Australasian College of Physicians.
Daniel Gallego Hernández (Ed.. Enfoques actuales en traducción económica e institucional. Actas del Congreso Internacional de Traducción Económica, Comercial, Financiera e Institucional. Suiça: Editorial Peter Lang, 2015. 254 p.

Directory of Open Access Journals (Sweden)

Miguel Tolosa Igualada

2016-05-01

Full Text Available http://dx.doi.org/10.5007/2175-7968.2016v36n2p291 Daniel Gallego Hernández (Ed.. Enfoques actuales en traducción económica e institucional. Actas del Congreso Internacional de Traducción Económica, Comercial, Financiera e Institucional. Suiça: Editorial Peter Lang, 2015. 254 p.
Neutron spectra from radionuclide sources for cardiac pacemakers

International Nuclear Information System (INIS)

Kluge, H.

1975-01-01

Neutron spectra from Plutonium 238 radioisotope batteries powering cardiac pacemakers are measured in the energy range above 0.7 MeV. The results are used to calculate radiation doses within a cylindrical phantom. There are only minor differences between the different types of plutonium 238-batteries and californium 252-batteries
Degradation and mineralization of organic UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) using UV-254 nm/H{sub 2}O{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Abdelraheem, Wael H.M. [Chemistry Department, Faculty of Science, Sohag University, Sohag 82524 (Egypt); Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); He, Xuexiang; Duan, Xiaodi [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); NIREAS-International Water Research Center, University of Cyprus, Nicosia 1678 (Cyprus); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); NIREAS-International Water Research Center, University of Cyprus, Nicosia 1678 (Cyprus)

2015-01-23

Graphical abstract: - Highlights: • UV-254 nm/H{sub 2}O{sub 2} AOP was utilized for the degradation and mineralization of PBSA and BSA. • Promotion of k{sub obs} with [H{sub 2}O{sub 2}]{sub 0} ≤ 4 mM and inhibition at higher [H{sub 2}O{sub 2}]{sub 0} were observed. • The S and N were released and monitored as SO{sub 4}{sup 2−} and NH{sub 4}{sup +}, respectively. • Br{sup −} inhibited both the degradation and mineralization much more significantly than Cl{sup −}. • There was an increase in [NH{sub 4}{sup +}] at higher [H{sub 2}O{sub 2}]{sub 0} and its further destruction at higher UV fluence. - Abstract: Various studies have revealed the non-biodegradable and endocrine disrupting properties of sulfonated organic UV absorbers, directing people's attention toward their risks on ecological and human health and hence their removal from water. In this study, UV-254 nm/H{sub 2}O{sub 2} advanced oxidation process (AOP) was investigated for degrading a model UV absorber compound 2-phenylbenzimidazole-5-sulfonic acid (PBSA) and a structurally similar compound 1H-benzimidazole-2-sulfonic acid (BSA), with a specific focus on their mineralization. At 4.0 mM [H{sub 2}O{sub 2}]{sub 0}, a complete removal of 40.0 μM parent PBSA and 25% decrease in TOC were achieved with 190 min of UV irradiation; SO{sub 4}{sup 2−} was formed and reached its maximum level while the release of nitrogen as NH{sub 4}{sup +} was much lower (around 50%) at 190 min. Sulfate removal was strongly enhanced by increasing [H{sub 2}O{sub 2}]{sub 0} in the range of 0–4.0 mM, with slight inhibition in 4.0–12.0 mM. Faster and earlier ammonia formation was observed at higher [H{sub 2}O{sub 2}]{sub 0}. The presence of Br{sup −} slowed down the degradation and mineralization of both compounds while a negligible effect on the degradation was observed in the presence of Cl{sup −}. Our study provides important technical and fundamental results on the HO{sup ·} based degradation and
Single-event burnout of power MOSFET devices for satellite application

International Nuclear Information System (INIS)

Xue Yuxiong; Tian Kai; Cao Zhou; Yang Shiyu; Liu Gang; Cai Xiaowu; Lu Jiang

2008-01-01

Single-event burnout (SEB) sensitivity was tested for power MOSFET devices, JTMCS081 and JTMCS062, which were made in Institute of Microelectronics, Chinese Academy of Sciences, using californium-252 simulation source. SEB voltage threshold was found for devices under test (DUT). It is helpful for engineers to choose devices used in satellites. (authors)

Daniel Gallego Hernández (Ed.). Enfoques actuales en traducción económica e institucional. Actas del Congreso Internacional de Traducción Económica, Comercial, Financiera e Institucional. Suiça: Editorial Peter Lang, 2015. 254 p.

OpenAIRE

Miguel Tolosa Igualada

2016-01-01

Daniel Gallego-Hernández (ed.). Current Approaches to Business and Institutional Translation. Proceedings of the International Conference on Economic, Business, Financial and Institutional Translation / Enfoques actuales en traducción económica e institucional. Actas del Congreso Internacional de Traducción Económica, Comercial, Financiera e Institucional. Suíça: Peter Lang, 2015, 254 páginas. ISBN 978-3-0343-1656-9.
Radioactive materials production

International Nuclear Information System (INIS)

Anon.

1985-01-01

The Radiochemical Processing Plant (RPP) at ORNL has served as the national repository and distribution center for 233 U for > 20 years. Several hundred kilograms of uranium, containing approximately 90 to 98% 233 U, are stored there in the form of metal, oxides, and nitrate solutions. All of these uranium materials contain small, but significant, concentrations of 232 U, ranging from 2 to 225 ppm. Most of the radioactivity associated with the 233 U comes from the decay daughters of 232 U (74-year half-life). The 252 Cf Industrial Sales/Loan Program involves loans of 252 Cf neutron sources to agencies of the US Government and sales of 252 Cf as the bulk oxide and as palladium-californium alloy pellets and wires. The program has been operated since 1968 in temporary facilities at the Savannah River Laboratory (SRL). The obsolete hot-cell facilities at SRL are now being decommissioned, and the program activities are being transferred to ORNL's Californium Facility in Bldg. 7930, which is managed by the staff of the Transuranium Processing Plant
Validation of the MCNP-DSP Monte Carlo code for calculating source-driven noise parameters of subcritical systems

International Nuclear Information System (INIS)

Valentine, T.E.; Mihalczo, J.T.

1995-01-01

This paper describes calculations performed to validate the modified version of the MCNP code, the MCNP-DSP, used for: the neutron and photon spectra of the spontaneous fission of californium 252; the representation of the detection processes for scattering detectors; the timing of the detection process; and the calculation of the frequency analysis parameters for the MCNP-DSP code
Magnetic measurements of the transuranium elements. Progress report, January 1, 1984-December 31, 1984

International Nuclear Information System (INIS)

Huray, P.G.; Nave, S.E.

1984-01-01

Measurements of the magnetic properties of dhcp californium-249 metal indicated the presence of three regions of differing magnetic character. Additional measurements are also reported. Magnetic moments and valence states of terbium in TbF 3 , BaTbO 3 , and TbO 1 8 are discussed. Progress on high-field operation of the micro-magnetic susceptometer is reported
Preparation and study of elemental californium-249

International Nuclear Information System (INIS)

Noe, M.; Peterson, J.R.

1975-01-01

Bulk samples of 249 Cf metal were prepared on the 10 μg scale via the Li metal vapor reduction of 249 CfF 3 . Above about 725 0 C elemental Cf exhibits a face-centered cubic (fcc) structure with an average, room-temperature lattice parameter of 5.75(1)A. Between about 600 0 C and 725 0 C, the stable form of Cf metal is another fcc structure with an average, room-temperature lattice parameter of 4.94(1)A. Below 600 0 C metallic Cf exhibits a double hexagonal closest packed (dhcp) structure with average, room temperature lattice parameters of a 0 = 3.39(1)A and c 0 = 11.01(5)A. By comparison of the metallic radii calculated for these three forms with those of the receding transuranium elements, it is suggested that the two, lower temperature modifications represent Cf with a metallic valence of three, while the highest temperature form represents a metallic valence of two. Although the data reported here are from the most complete study to date of elemental Cf, the limitations accompanying such microscale research are duly noted. (U.S.)
Photo-removal of sulfamethoxazole (SMX) by photolytic and photocatalytic processes in a batch reactor under UV-C radiation (λmax = 254 nm)

International Nuclear Information System (INIS)

Nasuhoglu, Deniz; Yargeau, Viviane; Berk, Dimitrios

2011-01-01

In this study, photolytic and photocatalytic removal of the antibiotic sulfamethoxazole (SMX) under UVC radiation (λ = 254 nm) was investigated. The light intensity distribution inside the batch photoreactor was characterized by azoxybenzene actinometry. The intensity of incident radiation was found to be a strong function of position inside the reactor. 12 mg L -1 of SMX was completely removed within 10 min of irradiation under UVC photolysis, compared to 30 min under TiO 2 photocatalysis. COD measurement was used as an indication of the mineralization efficiency of both processes and higher COD removal with photocatalysis was shown. After 6 h of reaction with photolysis and photocatalysis, 24% and 87% removal of COD was observed, respectively. Two of the intermediate photo-products were identified as sulfanilic acid and 3-amino-5-methylisoxazole by direct comparison of the HPLC chromatograms of standards to those of treated solutions. Ecotoxicity of treated and untreated solutions of SMX towards Daphnia magna was also investigated. It was found that a 3:1 ratio of sample to standard freshwater and a high initial concentration of 60 mg L -1 of SMX were used to obtain reliable and reproducible results. The photo-products formed during photocatalytic and photolytic processes were shown to be generally more toxic than the parent compound.
Solid-State Neutron Multiplicity Counting System Using Commercial Off-the-Shelf Semiconductor Detectors

Energy Technology Data Exchange (ETDEWEB)

Rozhdestvenskyy, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-08-09

This work iterates on the first demonstration of a solid-state neutron multiplicity counting system developed at Lawrence Livermore National Laboratory by using commercial off-the-shelf detectors. The system was demonstrated to determine the mass of a californium-252 neutron source within 20% error requiring only one-hour measurement time with 20 cm² of active detector area.
Tritium labelling of two highly selective agonists for CCK-B receptors : [[sup 3]H]propionyl-Tyr(SO[sub 3]Na)-gNle-mGly-Trp-(N-Me)Nle-Asp-Phe-NHsub (2) ([[sup 3]H]pBC 264) [[sup 3]H]propionyl-[gamma]D. Glu-Tyr(SO[sub 3]H)-Nle-D. Lys-Trp-Nle-Asp-Phe-NH[sub 2] ([[sup 3]H]pBC 254). [Cholecystokini-B receptors

Energy Technology Data Exchange (ETDEWEB)

Corringer, P J; Durieux, C; Ruiz-Gayo, M; Roques, B P [UA498 CNRS, U266 INSERM, UFR des Sciences Pharmaceutiques et Biologiques, 75 - Paris (France)

1992-06-01

Among the CCK-B receptor agonists reported to date, the two modified peptides BC 264 and BC 254 display a high affinity and selectivity for this binding site and are highly protected from enzymatic degradation. Recently, we reported the biological properties of a tritiated analog of this agonist, [[sup 3]H]pBC 264, which fullfils all the criteria required for in vitro as well as in vivo studies of the CCK-B receptor. On the other hand, BC 254 displays a high affinity for the CCK-B binding sites in the guinea-pig (K[sub i] = 0.56 nM) while its affinity in the rat is more than 60-fold lower, a difference which could be due to the occurrence of CCK-B receptor subtypes. In the present paper, we report the synthesis of [[sup 3]H]pBC 264 and of the new tritiated ligand [[sup 3]H]pBC 254 using [[sup 3]H] NPS (N-succinimidyl[2,3-[sup 3]H]propionate) as labelling agent. These two probes have high specific activity (70-100 Ci/mmol) and will enable extensive studies of the CCK-B receptors to be carried out. (author).
Citric complexes of trivalent cerium and berkelium

International Nuclear Information System (INIS)

Boulhassa, S.

1977-01-01

The extraction by thenoyltrifluoroacetone (TTA) in benzene of trivalent cerium, berkelium and californium, at the indicator scale, hydrolysis and complexation by citric acid of these cations are studied. The radionuclides used were 144 Ce, 249 Bk and 249 Cf respectively γ, β and α emitters. The solvent extraction technique of the elements by TTA in benzene from a perchloric medium at the ionic stength 0.1 was employed. The distribution coefficients D were measured by the γ, β or α radiometry. Cerium and berkelium, which have a comparable redox behavior, show in solution a relatively stable valency IV. Therefore the study by solvent extraction of their trivalent form required the standing up of complete reducing conditions of these elements and their stabilization in solution at the valency III. The thermodynamic data obtained for berkelium and californium contribute to understand the chemistry of these elements and permit to complete the third 'tetrad branch' of 5f elements from Cm 3+ to Es 3+ . This tetrad effect is a manifestation of thermodynamic consequence of the 'nephelauxetic effect'. As for Ce(III), the data confirm the pronounced acid property and may be show no neglected ligand effect for f 1 configuration [fr
Directed evolution of the periodic table: probing the electronic structure of late actinides.

Science.gov (United States)

Marsh, M L; Albrecht-Schmitt, T E

2017-07-25

Recent investigations of the coordination chemistry and physical properties of berkelium (Z = 97) and californium (Z = 98) have revealed fundamental differences between post-curium elements and lighter members of the actinide series. This review highlights these developments and chronicles key findings and concepts from the last half-century that have helped usher in a new understanding of the evolution of electronic structure in the periodic table.
Properties of neutron sources

International Nuclear Information System (INIS)

1987-03-01

The Conference presentations were divided into sessions devoted to the following topics: white neutron sources, primarily pulsed (6 papers); fast neutron fields (5 papers); Californium-252 prompt fission neutron spectra (14 papers); monoenergetic sources and filtered beams (11 papers); 14 MeV neutron sources (10 papers); selected special application (one paper); and a general interest session (4 papers). Individual abstracts were prepared separately for the papers
Computer-assisted nuclear fuel manufacture

International Nuclear Information System (INIS)

Maloney, J.P.; Schaumann, S.M.; Stone, E.

1976-01-01

At the ERDA Savannah River Plant, a process monitor, which incorporates an online digital computer, assists in manufacturing fuel elements used to produce nuclides such as plutonium, tritium, and californium in the plant's nuclear reactors. Also, inventory functions assist in safeguarding fissile material and protecting against accidental nuclear criticality. Terminals at strategic locations throughout the process area enable production operators to send and receive instructions and information on each manufacturing step
Photo-removal of sulfamethoxazole (SMX) by photolytic and photocatalytic processes in a batch reactor under UV-C radiation ({lambda}{sub max} = 254 nm)

Energy Technology Data Exchange (ETDEWEB)

Nasuhoglu, Deniz; Yargeau, Viviane [Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, H3A 2B2 (Canada); Berk, Dimitrios, E-mail: dimitrios.berk@mcgill.ca [Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, H3A 2B2 (Canada)

2011-02-15

In this study, photolytic and photocatalytic removal of the antibiotic sulfamethoxazole (SMX) under UVC radiation ({lambda} = 254 nm) was investigated. The light intensity distribution inside the batch photoreactor was characterized by azoxybenzene actinometry. The intensity of incident radiation was found to be a strong function of position inside the reactor. 12 mg L{sup -1} of SMX was completely removed within 10 min of irradiation under UVC photolysis, compared to 30 min under TiO{sub 2} photocatalysis. COD measurement was used as an indication of the mineralization efficiency of both processes and higher COD removal with photocatalysis was shown. After 6 h of reaction with photolysis and photocatalysis, 24% and 87% removal of COD was observed, respectively. Two of the intermediate photo-products were identified as sulfanilic acid and 3-amino-5-methylisoxazole by direct comparison of the HPLC chromatograms of standards to those of treated solutions. Ecotoxicity of treated and untreated solutions of SMX towards Daphnia magna was also investigated. It was found that a 3:1 ratio of sample to standard freshwater and a high initial concentration of 60 mg L{sup -1} of SMX were used to obtain reliable and reproducible results. The photo-products formed during photocatalytic and photolytic processes were shown to be generally more toxic than the parent compound.
Automated absolute activation analysis with californium-252 sources

International Nuclear Information System (INIS)

MacMurdo, K.W.; Bowman, W.W.

1978-09-01

A 100-mg 252 Cf neutron activation analysis facility is used routinely at the Savannah River Laboratory for multielement analysis of many solid and liquid samples. An absolute analysis technique converts counting data directly to elemental concentration without the use of classical comparative standards and flux monitors. With the totally automated pneumatic sample transfer system, cyclic irradiation-decay-count regimes can be pre-selected for up to 40 samples, and samples can be analyzed with the facility unattended. An automatic data control system starts and stops a high-resolution gamma-ray spectrometer and/or a delayed-neutron detector; the system also stores data and controls output modes. Gamma ray data are reduced by three main programs in the IBM 360/195 computer: the 4096-channel spectrum and pertinent experimental timing, counting, and sample data are stored on magnetic tape; the spectrum is then reduced to a list of significant photopeak energies, integrated areas, and their associated statistical errors; and the third program assigns gamma ray photopeaks to the appropriate neutron activation product(s) by comparing photopeak energies to tabulated gamma ray energies. Photopeak areas are then converted to elemental concentration by using experimental timing and sample data, calculated elemental neutron capture rates, absolute detector efficiencies, and absolute spectroscopic decay data. Calculational procedures have been developed so that fissile material can be analyzed by cyclic neutron activation and delayed-neutron counting procedures. These calculations are based on a 6 half-life group model of delayed neutron emission; calculations include corrections for delayed neutron interference from 17 O. Detection sensitivities of 239 Pu were demonstrated with 15-g samples at a throughput of up to 140 per day. Over 40 elements can be detected at the sub-ppM level
Savannah River Plant californium-252 Shuffler electronics manual

International Nuclear Information System (INIS)

Bourret, S.C.; Crane, T.W.; Eccleston, G.W.; Gallegos, E.A.; Garcia, D.L.

1980-03-01

Detailed information is presented in this report, an electronics manual for the Savannah River Plant Shuffler, about the electronics associated with the various control and data acquisition functions of the Shuffler subsystems. Circuit diagrams, interconnection information, and details about computer control and programming are included
Savannah River Plant Californium-252 Shuffler software manual

International Nuclear Information System (INIS)

Johnson, S.S.; Crane, T.W.; Eccleston, G.W.

1979-03-01

A software manual for operating the Savannah River Plant Shuffler nondestructive assay instrument is presented. The procedures for starting up the instrument, making assays, calibrating, and checking the performance of the hardware units are described. A list of the error messages with an explanation of the circumstances prompting the message and possible corrective measures is given. A summary of the software package is included showing the names and contents of the files and subroutines. The procedure for modifying the software package is outlined
Quantum mechanical and spectroscopic (FT-IR, 13C, 1H NMR and UV) investigations of 2-(5-(4-Chlorophenyl)-3-(pyridin-2-yl)-4,5-dihydropyrazol-1-yl)benzo[d]thiazole by DFT method

Science.gov (United States)

Diwaker

2014-07-01

The electronic, NMR, vibrational, structural properties of a new pyrazoline derivative: 2-(5-(4-Chlorophenyl)-3-(pyridine-2-yl)-4,5-dihydropyrazol-1-yl)benzo[d]thiazole has been studied using Gaussian 09 software package. Using VEDA 4 program we have reported the PED potential energy distribution of normal mode of vibrations of the title compound. We have also reported the 1H and 13C NMR chemical shifts of the title compound using B3LYP level of theory with 6-311++G(2d,2p) basis set. Using time dependent (TD-DFT) approach electronic properties such as HOMO and LUMO energies, electronic spectrum of the title compound has been studied and reported. NBO analysis and MEP surface mapping has also been calculated and reported using ab initio methods.
Computer-assisted nuclear fuel manufacture

International Nuclear Information System (INIS)

Maloney, J.P.; Schaumann, C.M.; Stone, E.

1976-06-01

At the ERDA Savannah River Plant, a process monitor, which incorporates an online digital computer, assists in manufacturing fuel elements used to produce nuclides such as plutonium, tritium, and californium in the plant's nuclear reactors. Also, inventory functions assist in safeguarding fissile material and protecting against accidental nuclear criticality. Terminals at strategic locations throughout the process area enable production operators to send and receive instructions and information on each manufacturing step. 11 fig
The protective cell petrus for the production of californium 252; Cellule blindee petrus pour la production et l'etude du californium 252

Energy Technology Data Exchange (ETDEWEB)

Sontag, R; Berger, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1967-07-01

The alpha, beta, gamma, neutron cell which is described in the present paper is devoted to the transplutonium element production and study. It is located at the CEN in Fontenay-aux-Roses (France). The 4 feet ordinary concrete shielding made of stacked blocs allows the manipulation of radioactive sources as high as 1000 curies of 1 MeV gamma rays and with a fast neutrons flux of 10{sup 9} n.cm{sup -2}.s{sup -1}. The airtight alpha containment box is equipped with two transfer systems, one consists of a parallelepiped shaped airtight box located in a turntable, the other uses standard cylindrical containers made of polyethylene. The general equipment and the main setting up are also described. (authors) [French] La cellule alpha, beta, gamma, neutron, qui fait l'objet du present article, est destinee a la production et a l'etude des elements transplutoniens. Elle est construite au C.E.N. de Fontenay-aux-Roses (France). La protection biologique, calculee pour une activite de 1000 curies de rayonnement gamma d'energie 1 MeV accompagnee d'un flux de neutrons rapides de 10{sup 9}/cm{sup 2}s, est constituee par des parois en beton de 1,20 m d'epaisseur. L'enceinte alpha est une boite etanche qui comporte devx systemes de transferts: l'un consiste en une boite parallelepipedique etanche logee dans un barillet, l'autre fait appel a des recipients cylindriques standard en polyethylene. L'equipement general et les installations les plus importantes sont ensuite decrits. (auteurs)
Heavy ion tests on programmable VLSI

International Nuclear Information System (INIS)

Provost-Grellier, A.

1989-11-01

The radiation from space environment induces operation damages in onboard computers systems. The definition of a strategy, for the Very Large Scale Integrated Circuitry (VLSI) qualification and choice, is needed. The 'upset' phenomena is known to be the most critical integrated circuit radiation effect. The strategies for testing integrated circuits are reviewed. A method and a test device were developed and applied to space applications candidate circuits. Cyclotron, synchrotron and Californium source experiments were carried out [fr

Charge breeding of radioactive isotopes at the CARIBU facility with an electron beam ion source

Science.gov (United States)

Vondrasek, R. C.; Dickerson, C. A.; Hendricks, M.; Ostroumov, P.; Pardo, R.; Savard, G.; Scott, R.; Zinkann, G.

2018-05-01

An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne National Laboratory as part of the californium rare ion breeder upgrade. For the past year, the EBIS-CB has been undergoing commissioning as part of the ATLAS accelerator complex. It has delivered both stable and radioactive beams with A/Q 18% into a single charge state. The operation of this device, challenges during the commissioning phase, and future improvements will be discussed.
Safety analysis report for packaging: neutron shipping cask, model 0.5T

International Nuclear Information System (INIS)

Peterson, R.T.

1976-01-01

The Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The shipping cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual
NWIS casting measurements taken during demonstrations to Russian visitors

International Nuclear Information System (INIS)

Mullens, J.A.; Valentine, T.E.; Mihalczo, J.T.

1998-01-01

This report describes a set of NWIS measurements made during demonstrations to Russian visitors on August 28, 1997. These measurements will be given to the Russian visitors from Arzamus-16 as part of their NWIS training (part of a DOE laboratory-to-laboratory exchange program). These measurements are made on standard highly enriched Uranium annular castings (as used for storage). Associated NWIS calibration runs were made in air (no casting, just the NWIS Californium source and detectors)
Health physics aspects of 252Cf

International Nuclear Information System (INIS)

Bhagwat, A.M.

1974-01-01

After briefly describing the methods of production, radioactive, chemical and biological properties of californium-252, its health physics aspects are reviewed in detail. Its external and internal radiation hazards can be minimised through control of radiation and contamination and proper shield design. Use of various shielding materials is evaluated. The following aspects are also discussed : (1) radiation detectors for neutrons and gamma radiation (2) personnel monitoring techniques (3) bioassay and (4) storage and transportation. (M.G.B.)
Survey of potential markets for devices using Californium-252

International Nuclear Information System (INIS)

Permar, P.H.

1975-01-01

Potential applications for devices or systems containing 252 Cf in the years from 1975 to 1980 are estimated. The estimated number of devices and associated business value were derived from a survey of 46 industrial, educational and governmental organizations conducted from Jan. to May, 1975. Applications for devices and systems based on 252 Cf are expected to increase by a factor of 7 in the 6-y period from 1975 to 1980. The annual business value of 252 Cf devices should increase from 1.5 million dollars in 1975 to 10.8 million dollars in 1980. The potential European market should be several times as large as the US market, based on actual sales of 252 Cf, which have been two to four times greater in Europe than in the US
Californium-252 interstitial implants in carcinoma of the tongue

International Nuclear Information System (INIS)

Vtyurin, B.M.; Ivanov, V.N.; Medvedev, V.S.; Galantseva, G.F.; Abdulkadyrov, S.A.; Ivanova, L.F.; Petrovskaya, G.A.; Plichko, V.I.

1985-01-01

A clinical study using 252 Cf sources in brachytherapy of tumors began in the Research Institute of Medical Radiology of the Academy of Medical Sciences of the USSR in 1973. 252 Cf afterloading cells were utilized by the method of simple afterloading. Dosimetry and radiation protection of medical personnel were developed. To substantiate optimal therapeutic doses of 252 Cf neutrons, a correlation of dose, time, and treatment volume factors with clinical results of 252 Cf interstitial implants in carcinoma of the tongue for 47 patients with a minimum follow-up period of 1 year was studied. Forty-nine interstitial implants have been performed. Seventeen patients received 252 Cf implants alone (Group I), 17 other patients received 252 Cf implants in combination with external radiation (Group II), and 15 patients were treated with interstitial implants for recurrent or residual tumors (Groups III). Complete regression of carcinoma of the tongue was obtained in 48 patients (98%). Thirteen patients (27%) developed radiation necrosis. The therapeutic dose of neutron radiation from 252 Cf sources in interstitial radiotherapy of primary tongue carcinomas (Group I) was found to be 7 to 9 Gy. Optimal therapeutic neutron dose in combined interstitial and external radiotherapy of primary tumors (Group II) was 5 to 6 Gy with an external radiation dose of 40 Gy. For recurrent and residual tumors (Group III), favorable results were obtained with tumor doses of 6.5 to 7 Gy
Undergraduate experiments using the neutron radiation from californium-252

International Nuclear Information System (INIS)

Rossel, J.; Golecki, I.

1976-01-01

Three experiments designed to demonstrate and measure several properties of the neutron radiation emitted by a 3μg 252 Cf source are described. The experiments constitute a special project carried out by a third-year undergraduate student at the Institute of Physics of the University of Neuchatel. The 252 Cf source is enclosed in a shield which allows a pencil of fast neutrons to pass through a central tube, while reducing the ambient radiation below the tolerance level. The shield consists of layers of borated paraffin wax, iron and cadmium. The first experiment uses an air-alcohol diffusion cloud chamber for the demonstration of tracks of recoil protons produced by the neutrons. Semi-quantitative measurements of track lengths give the correct order of magnitude of the proton energies. In the second experiment a liquid scintillator detector is used to scan the beam profile across the radiation shield enclosing the source. A pulse-shape-discrimination system discriminates between neutrons and gamma photons. The third experiment makes use of the nuclear emulsion technique to study the neutron energy distribution of 252 Cf. Preliminary results are compared with published values. (author)
Safety analysis report for packaging: neutron shipping cask, model 4T

International Nuclear Information System (INIS)

Peterson, R.T.

1977-01-01

This Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual, Safety Standards for the Packaging of Fissile and Other Radioactive Materials
30 CFR 254.6 - Definitions.

Science.gov (United States)

2010-07-01

... dangerous or impossible to respond to a spill. Area Contingency Plan means an Area Contingency Plan prepared... Contingency Plan means the National Oil and Hazardous Substances Pollution Contingency Plan prepared and... Comprehensive Environmental Response Compensation and Liability Act (42 U.S.C. 9605). National Contingency Plan...
36 CFR 254.3 - Requirements.

Science.gov (United States)

2010-07-01

... of fish and wildlife habitats, cultural resources, watersheds, and wilderness and aesthetic values... use of the conveyed Federal land will not substantially conflict with established management... human health and the environment with respect to any such substances remaining on the property has been...
16 CFR 254.1 - Definitions.

Science.gov (United States)

2010-01-01

... corporate charter to operate or license to do business as a school and should not be used unless the represented “approval” has been affirmatively required or authorized by State or Federal law. (c) Industry...
36 CFR 254.2 - Definitions.

Science.gov (United States)

2010-07-01

..., use, physical characteristics, and other amenities. Arbitration is a process to resolve a disagreement... public domain for national forest purposes and the Geothermal Steam Act of 1970 (30 U.S.C. 1001 et seq.... Resource values means any of the various commodity values or non-commodity values, such as wildlife habitat...
36 CFR 254.9 - Appraisals.

Science.gov (United States)

2010-07-01

....9 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP... contributory value of any interest in land such as water rights, minerals, or timber, to the extent they are... the physical characteristics of the land being appraised; a statement of all encumbrances; title...
Dicty_cDB: [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available VF (Link to library) VFC254 (Link to dictyBase) - - - Contig-U15456-1 VFC254P (Link... to Original site) VFC254F 509 VFC254Z 569 VFC254P 1078 - - Show VFC254 Library VF (Link to library) Clone ID VFC254 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U15456-1 Original site URL http://dict...mology vs DNA Score E Sequences producing significant alignments: (bits) Value N Y16962 |Y16962.1 Dictyostel...ium discoideum mRNA for cathepsin D. 910 0.0 3 AJ243946 |AJ243946.1 Dictyostelium
Method for measuring multiple scattering corrections between liquid scintillators

Energy Technology Data Exchange (ETDEWEB)

Verbeke, J.M., E-mail: verbeke2@llnl.gov; Glenn, A.M., E-mail: glenn22@llnl.gov; Keefer, G.J., E-mail: keefer1@llnl.gov; Wurtz, R.E., E-mail: wurtz1@llnl.gov

2016-07-21

A time-of-flight method is proposed to experimentally quantify the fractions of neutrons scattering between scintillators. An array of scintillators is characterized in terms of crosstalk with this method by measuring a californium source, for different neutron energy thresholds. The spectral information recorded by the scintillators can be used to estimate the fractions of neutrons multiple scattering. With the help of a correction to Feynman's point model theory to account for multiple scattering, these fractions can in turn improve the mass reconstruction of fissile materials under investigation.
Nuclear assay of coal. Volume 1. Coal composition by prompt neutron activation analysis: basic experiments. Final report

International Nuclear Information System (INIS)

Reynolds, G.; Bozorganesh, H.; Elias, E.; Gozani, T.; Maung, T.; Orphan, V.

1979-01-01

Using californium-252 as a source of exciting neutrons, prompt gamma photons emitted by elemental nuclei in the coal have been measured using several detectors, including sodium--iodide and germanium--lithium. Several coal types, including bituminous, subbituminous lignite and anthracite were crushed to various top sizes and analyzed carefully be traditional ASTM wet chemistry techniques at two or three different laboratories. The elements (sulfur, hydrogen, carbon, aluminum, silicon, iron, calcium, sodium, nitrogen, and chlorine) were determined by prompt neutron activations and the quantities compared with those of the wet chemical analyses
Actinides

International Nuclear Information System (INIS)

Martinot, L.; Fuger, J.

1985-01-01

The oxidation behavior of the actinides is explained on the basis of their electronic structure. The actinide elements, actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium, and laurencium are included. For all except the last three elements, the points of discussion are oxidation states, Gibbs energies and potentials, and potential diagram for the element in acid solution; and thermodynamic properties of these same elements are tabulated. References are cited following discussion of each element with a total of 97 references being cited. 13 tables
The protective cell petrus for the production of californium 252

International Nuclear Information System (INIS)

Sontag, R.; Berger, R.

1967-01-01

The alpha, beta, gamma, neutron cell which is described in the present paper is devoted to the transplutonium element production and study. It is located at the CEN in Fontenay-aux-Roses (France). The 4 feet ordinary concrete shielding made of stacked blocs allows the manipulation of radioactive sources as high as 1000 curies of 1 MeV gamma rays and with a fast neutrons flux of 10 9 n.cm -2 .s -1 . The airtight alpha containment box is equipped with two transfer systems, one consists of a parallelepiped shaped airtight box located in a turntable, the other uses standard cylindrical containers made of polyethylene. The general equipment and the main setting up are also described. (authors) [fr
Effect of Key Parameters on the Photocatalytic Oxidation of Toluene at Low Concentrations in Air under 254 + 185 nm UV Irradiation

Energy Technology Data Exchange (ETDEWEB)

Quici, Natalia; Vera, Maria L.; Choi, Hyeok; Puma, Gianluca Li; Dionysiou, Dionysios D.; Litter, Marta I.; Destaillats, Hugo

2009-07-01

The effect of key experimental parameters on the removal of toluene under 254 + 185 nm irradiation was investigated using a benchtop photocatalytic flow reactor. Toluenewas introduced at low concentrations between 10 and 500 ppbv, typical of indoorenvironments, and reacted on TiO2-coated Raschig rings. Two different TiO2-coated rings were prepared: in one case, by dip-coating using a P25 aqueous suspension and, on the other, using an organic/inorganic sol-gel method that produced thin films of mesoporous anatase. Flow rates in the photoreactor varied between 4 L min-1 and 125 mL min-1, leading to residence times in the range 100 ms< tau< 2 s. For these conditions, toluene removal efficiencies were between 30 and 90percent, indicating that the system did not achieve total conversion in any case. For each air flow rate, the conversion oftoluene was significantly higher when the reactor length was 10 cm, as compared with 5 cm; however, only marginal increases in conversions were achieved in the two reactor lengths at equal residence time and different concentration of toluene, suggesting that that the reactor is effectively behaving as an ideal reactor and that the reaction is first-order in the concentration of toluene. Experiments were carried out between 0 and 66percent relative humidity (RH), the fastest reaction rate being observed at moderately low humidity conditions (10percent RH), with respect to both dry air and higher humidity levels. Formaldehyde was formed as a partial oxidation byproduct at low and at high residence times (240 and 960 ms), although higher formaldehyde molar yields (up to 20percent) were observed at low tau (240 ms) and moderate humidity conditions (10 and 33percent), suggesting that both tau and RH can be optimized toreduce the formation of harmful intermediates. Toluene removal efficiency increased with the TiO2 thickness (i.e., mass) until a maximum value of 500 nm, beyond which the removal efficiency decreased. This should be
Radiation protection data sheet. Radiation protection data sheets for the use of radionuclides in unsealed sources

International Nuclear Information System (INIS)

Anon.

1999-01-01

These radiation protection data sheet are devoted to responsible persons and employees of various laboratories or medical, pharmaceutical, university and industrial departments where radionuclides are handled as well as all the persons who attend to satisfy in this field. They contain the essential radiation protection data for the use of unsealed sources: physical characteristics, risk assessment, administrative procedures, recommendations, regulations and bibliography. This new series includes the following radionuclides: californium 252, curium 244, gallium 67, indium 113m, plutonium 238, plutonium 239, polonium 210, potassium 42, radium 226, thorium 232, uranium 238 and zinc 65. (O.M.)

Determination of the relative power density distribution in a heterogeneous reactor from the results of measurements of the reactivity effects and the neutron importance function

International Nuclear Information System (INIS)

Bobrov, A. A.; Glushkov, E. S.; Zimin, A. A.; Kapitonova, A. V.; Kompaniets, G. V.; Nosov, V. I.; Petrushenko, R. P.; Smirnov, O. N.

2012-01-01

A method for experimental determination of the relative power density distribution in a heterogeneous reactor based on measurements of fuel reactivity effects and importance of neutrons from a californium source is proposed. The method was perfected on two critical assembly configurations at the NARCISS facility of the Kurchatov Institute, which simulated a small-size heterogeneous nuclear reactor. The neutron importance measurements were performed on subcritical and critical assemblies. It is shown that, along with traditionally used activation methods, the developed method can be applied to experimental studies of special features of the power density distribution in critical assemblies and reactors.
Publications | Page 254 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

Madagascar, the world's fourth largest island, is home to an astonishing range of life forms found nowhere else on the planet. Much of this biodiversity is highly vulnerable to climate change. So too are ... Blood on the Stone Ian Smillie in his own words. Below, Ian Smillie traces his involvement in the struggle to halt conflict ...
Reference: 254 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available plant cell growth and identify a plant S-acyl transferase, an essential research tool if we are to unders...tand how this important, reversible lipid modification operates in plant cells. The
Publications | Page 254 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

restricted access). India''s trade policy has seen a marked shift towards regional trade agreements (RTAs). However, results of this survey show that a Generalized Scheme of Preferences (GSP) is a better preference-giving scheme than all of India''s ...
7 CFR 1944.254 - Program costs.

Science.gov (United States)

2010-01-01

... Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... supplies (including food) necessary to provide services; (iv) Operational costs of a transportation service... development of the application and plan of operations before the effective date of CHSP grant award; (vi...
Grover, Dr Arun Kumar

Indian Academy of Sciences (India)

Specialization: Magnetism & Superconductivity, Vortex State Studies in Superconductors, Strongly Correlated Systems Address: Vice Chancellor, Panjab University, Chandigarh 160 014, U.T.. Contact: Office: (0172) 254 1945. Residence: (0172) 254 1428. Fax: (0172) 254 1022. Email: vc@pu.ac.in, arunkgrover@gmail.com.
Spectrum-averaged cross-section measurement of /sup 103/Rh(n,n)/sup 103m/Rh in the /sup 252/Cf fission neutron spectrum

International Nuclear Information System (INIS)

Lamaze, G.P.; Schima, F.J.; Eisenhauer, C.M.; Spiegel, V.

1988-01-01

Because of the similarity in energy dependence of the /sup 103/Rh(n,n') differential cross section to the kerma muscle response function for neutrons, rhodium may be useful as a neutron kerma monitor. In support of its use as a neutron monitor, the spectrum-averaged cross section σ-bar has been measured for a /sup 252/Cf fission neutron spectrum. Pairs of thin rhodium samples were irradiated on opposite sides of a thinly encapsulated /sup 252/Cf neutron source. The neutron emission rate of the /sup 252/Cf source was determined by the manganous sulfate (MnSO/sub 4/) bath technique. In this method, the californium source emission rate is determined by comparison to the known emission rate of NBS-I, a standard radium-beryllium neutron source. The neutron fluence incident on the rhodium samples is determined from the californium source strength, average sample-to-source distance, and the duration of the irradiation. Corrections are made for neutron scattering saturation of activity, and attenuation of the X rays by the sample during counting. The X rays were detected with an intrinsic germanium detector designed specifically for low-energy X-ray detection. The activity was not determined by absolute counting so that the final results depend on the value of P/sub Κx/, to total Κ X-ray emission probability. The results of five separate irradiations yield a value of σ-bar . P/sub Κx/ = 62.3 +- 1.9 mb. Using the most recently published value of P/sub Κx/ gives a value of σ-bar = 739 +- 22 mb. A discussion of systematic uncertainties is given
Use of californium-252 sources in Hungary for teaching and research

International Nuclear Information System (INIS)

Csikai, J.

1976-01-01

An activation facility was designed to accommodate up to 50 mg of 252 Cf; it contains at present a 500 μg source. The absolute values of thermal, epithermal and fast neutron fluxes were determined by the foil activation method using In, Dy, Au, Al and Fe detectors. Cross-sections averaged for unmoderated 252 Cf neutrons were determined for 22 different reactions for elements with atomic weights lying between A=27 and 204. The sensitivity for determination of Al, Ti, Cu, As, Sr, Mo, In, Cd, Ba, Au, Hg and Pb was calculated for NaI(Tl) and Ge(Li) detectors. Average (n,2n) cross-sections for 252 Cf spectrum were calculated for 49 nuclei lying between A=14 and 204. Angular distributions and cross-sections for the fragments from 252 Cf neutron-induced fission of 232 Th and 238 U were measured. Titanium in bauxite and manganese in aluminium alloys were determined with a 252 Cf source. The applicability of solid-state track detectors for neutron dosimetry, radiography and for the determination of fuel burn-up were investigated using 252 Cf neutron and fragment sources. Characteristics of a jumping spark counter for counting fission fragments were studied with 252 Cf sources. (author)
Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

International Nuclear Information System (INIS)

Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

1976-01-01

This paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: the spontaneous californium-252 fission neutron spectrum standard field; the thermal-neutron induced uranium-235 fission neutron spectrum standard field; the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN-ΣΣ facilities; the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility; the reference neutron field at the center of the 10% enriched uranium metal, cylindrical, fast critical; the (primary) Intermediate-Energy Standard Neutron Field
Development of a transportable neutron radiography system for non-destructive tests application

International Nuclear Information System (INIS)

Silva, Ademir X. da; Crispim, Verginia R.

1999-01-01

This paper presents a study of a transportable neutron radiography system utilizing californium-252. Studies about moderation, collimation and shielding are showed. A Monte Carlo Code, MCNP3b, has been used to obtain a maximum and more homogeneous thermal neutron flux in the collimator outlet next to the image plain, and an adequate radiation shielding to attend radiological protection rules. With the presented collimator, it was possible to obtain for the thermal neutron flux, at the collimator outlet and next to the image plain, a L/D ratio 7,5, for neutron flux up to 6 X 10 -6 cm -2 .s -1 per neutron source. (author)
Neutron crosstalk between liquid scintillators

Energy Technology Data Exchange (ETDEWEB)

Verbeke, J.M., E-mail: verbeke2@llnl.gov; Prasad, M.K., E-mail: prasad1@llnl.gov; Snyderman, N.J., E-mail: snyderman1@llnl.gov

2015-09-11

A method is proposed to quantify the fractions of neutrons scattering between liquid scintillators. Using a spontaneous fission source, this method can be utilized to quickly characterize an array of liquid scintillators in terms of crosstalk. The point model theory due to Feynman is corrected to account for these multiple scatterings. Using spectral information measured by the liquid scintillators, fractions of multiple scattering can be estimated, and mass reconstruction of fissile materials under investigation can be improved. Monte Carlo simulations of mono-energetic neutron sources were performed to estimate neutron crosstalk. A californium source in an array of liquid scintillators was modeled to illustrate the improvement of the mass reconstruction.
Neutron crosstalk between liquid scintillators

International Nuclear Information System (INIS)

Verbeke, J.M.; Prasad, M.K.; Snyderman, N.J.

2015-01-01

A method is proposed to quantify the fractions of neutrons scattering between liquid scintillators. Using a spontaneous fission source, this method can be utilized to quickly characterize an array of liquid scintillators in terms of crosstalk. The point model theory due to Feynman is corrected to account for these multiple scatterings. Using spectral information measured by the liquid scintillators, fractions of multiple scattering can be estimated, and mass reconstruction of fissile materials under investigation can be improved. Monte Carlo simulations of mono-energetic neutron sources were performed to estimate neutron crosstalk. A californium source in an array of liquid scintillators was modeled to illustrate the improvement of the mass reconstruction
Radiological safety considerations in the design and operation of the ORNL Transuranium Research Laboratory (TRL)

International Nuclear Information System (INIS)

Haynes, C.E.

1976-01-01

The Transuranium Research Laboratory (TRL) is the central facility at Oak Ridge National Laboratory (ORNL) for chemical and physical research involving transuranium elements. Transuranium Research Laboratory investigations are about equally divided between studies of inorganic and structural chemistry of the heavy elements and nuclear structure and properties of their isotopes. Elements studied include neptunium, plutonium, americium, curium, berkelium, californium, and einsteinium, each in microgram-to-gram quantities depending upon availability and experimental requirements. This paper describes an eight-step safety procedure followed in planning and approving individual research projects. This procedure should provide an optimum margin of safety and should permit the accomplishment of successful research
Determination of alpha activity and fissile mass content in solid waste by systems using neutron interrogation

International Nuclear Information System (INIS)

Romeyer Dherbey, J.; Lacruche, G.; Berne, R.; Auge, J.; Martin Deidier, L.; Butez, M.

1990-01-01

The Quantitative control (determination of heavy nuclides and alpha activity) of alpha radioactive wastes is necessary, particularly to determine if the waste is in accordance with the surface storage limits. In order to reduce the uncertainty on the alpha activity resulting from unknown isotopic composition, inhomogeneity of heavy nuclides in the matrix, combination of several methods is necessary. In the paper we present the Cadarache development work in the NDA of solid waste using the Californium shuffler, 14 Mev neutron generator, and also passive techniques such as neutron emission measurement and gamma spectrometry. Experimental systems combining active and passive methods are presented (COSAC, BANCO, DANAIDE, PROMETHEE)
Beam test of a grid-less multi-harmonic buncher

International Nuclear Information System (INIS)

Ostroumov, P.N.; Aseev, V.N.; Barcikowski, A.; Clifft, B.; Pardo, R.; Sharamentov, S.I.; Sengupta, M.

2008-01-01

The Argonne Tandem Linear Accelerator System (ATLAS) is the first superconducting heavy-ion linac in the world. Currently ATLAS is being upgraded with the Californium Rare Ion Breeder Upgrade (CARIBU). The latter is a funded project to expand the range of shortlived, neutron-rich rare isotope beams available for nuclear physics research at ATLAS. To avoid beam losses associated with the existing gridded multi-harmonic buncher (MHB), we have developed and built a grid-less four-harmonic buncher with fundamental frequency of 12.125 MHz. In this paper, we report the results of the MHB commissioning and ATLAS beam performance with the new buncher.
Composition containing transuranic elements for use in the homeopathic treatment of aids

International Nuclear Information System (INIS)

Lustig, D.

1996-01-01

A homeopathic remedy consisting of a composition containing one or more transuranic elements, particularly plutonium, for preventing and treating acquired immunodeficiency syndrome (AIDS) in humans, as well as seropositivity for human immunodeficiency virus (HIV). Said composition is characterized in that it uses any chemical or isotopic form of one or more transuranic elements (neptunium, plutonium, americium, curium, berkelium, californium or einsteinium), particularly plutonium, said form being diluted and dynamized according to conventional homeopathic methods, particularly the so-called Hahnemann and Korsakov methods, and provided preferably but not exclusively in the form of lactose and/or saccharose globules or granules impregnated with the active principle of said composition. (author)
PROCEEDINGS OF THE SYMPOSIUM COMMEMORATING THE 25th ANNIVERSARY OF ELEMENTS 97 and 98 HELD ON JAN. 20, 1975

Energy Technology Data Exchange (ETDEWEB)

Seaborg, Glenn T.; Street Jr., Kenneth; Thompson, Stanley G.; Ghiorso, Albert

1976-07-01

This volume includes the talks given on January 20, 1975, at a symposium in Berkeley on the occasion of the celebration of the 25th anniversary of the discovery of berkelium and californium. Talks were given at this symposium by the four people involved in the discovery of these elements and by a number of people who have made significant contributions in the intervening years to the investigation of their nuclear and chemical properties. The papers are being published here, without editing, in the form in which they were submitted by the authors in the months following the anniversary symposium, and they reflect rather faithfully the remarks made on that occasion.
TOWARD AN IMPROVED UNDERSTANDING OF STRUCTURE AND MAGNETISM IN NEPTUNIUM AND PLUTONIUM PHOSPHONATES AND SULFONATES

Energy Technology Data Exchange (ETDEWEB)

Albrecht-Schmitt, Thomas

2012-03-01

This grant supported the exploratory synthesis of new actinide materials with all of the actinides from thorium to californium with the exceptions of protactinium and berkelium. We developed detailed structure-property relationships that allowed for the identification of novel materials with selective ion-exchange, selective oxidation, and long-range magnetic ordering. We found novel bonding motifs and identified periodic trends across the actinide series. We identified structural building units that would lead to desired structural features and novel topologies. We also characterized many different spectroscopic trends across the actinide series. The grant support the preparation of approximately 1200 new compounds all of which were structurally characterized.
Triton and alpha-particle contribution from LiF converter for neutron dosimeter

CERN Document Server

Camacho, M E; Balcazar, M

1999-01-01

A personnel neutron dosimeter prototype based on chemical and electrochemical etched CR-39 detector, combined with LiF converter, has been calibrated using an ICRP-like phantom, under a heavy-water moderated Californium source neutron spectra; A conversion factor of 1.052+-126 spots cm sup - sup 2 mSv sup - sup 1 was obtained. The sealing properties of the detector holder showed a ten-fold reduction in radon background when it was tested in a high radon atmosphere. A convenient mechanical shock resistance was achieved in LiF converters by sintering to 11 tons pressure LiF powder at 650 deg. C, during one hour.
Destruction of microcystins (cyanotoxins) by UV-254 nm-based direct photolysis and advanced oxidation processes (AOPs): influence of variable amino acids on the degradation kinetics and reaction mechanisms.

Science.gov (United States)

He, Xuexiang; de la Cruz, Armah A; Hiskia, Anastasia; Kaloudis, Triantafyllos; O'Shea, Kevin; Dionysiou, Dionysios D

2015-05-01

Hepatotoxic microcystins (MCs) are the most frequently detected group of cyanobacterial toxins. This study investigated the degradation of common MC variants in water, MC-LR, MC-RR, MC-YR and MC-LA, by UV-254 nm-based processes, UV only, UV/H2O2, UV/S2O8(2-) and UV/HSO5(-). Limited direct photolysis of MCs was observed, while the addition of an oxidant significantly improved the degradation efficiency with an order of UV/S2O8(2-) > UV/HSO5(-) > UV/H2O2 at the same initial molar concentration of the oxidant. The removal of MC-LR by UV/H2O2 appeared to be faster than another cyanotoxin, cylindrospermopsin, at either the same initial molar concentration or the same initial organic carbon concentration of the toxin. It suggested a faster reaction of MC-LR with hydroxyl radical, which was further supported by the determined second-order rate constant of MCs with hydroxyl radical. Both isomerization and photohydration byproducts were observed in UV only process for all four MCs; while in UV/H2O2, hydroxylation and diene-Adda double bond cleavage byproducts were detected. The presence of a tyrosine in the structure of MC-YR significantly promoted the formation of monohydroxylation byproduct m/z 1061; while the presence of a second arginine in MC-RR led to the elimination of a guanidine group and the absence of double bond cleavage byproducts. It was therefore demonstrated in this study that the variable amino acids in the structure of MCs influenced not only the degradation kinetics but also the preferable reaction mechanisms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Study of reproducibility of measurements with the spectrometer of Bonner multispheres

International Nuclear Information System (INIS)

Azevedo, G.A.; Pereira, W.W.; Patrao, K.C.S.; Fonseca, E.S.

2013-01-01

This work aims to study the metrological behavior of the Bonner Multisphere Spectrometer (BMS) of the LN / LNMRI / IRD - Laboratorio Metrologia de Neutrons / Laboratorio Nacional de Metrologia e Radiacao Ionizante / Instituto de Radioprotecao e Dosimetria, for measurements in repeatability and reproducibility conditions. Initially, a simulation was done by applying the Monte Carlo method, using the MCNP code and respecting the ISO 8529-1 (2001), using the sources of Californium ( 252 Cf), Americium-Beryllium ( 241 AmBe) and californium in heavy water (Cf + D 2 O), all located at a distance of 100 cm from the neutron detector ( 6 Li (Eu) - crystal scintillator). In this program, the counting of neutrons that are captured by the detector was made. The source is located in the center of a sphere of radius 300 cm. Analyzes the impact of these neutrons in a point of the sphere wall, which in this case acted as a neutron detector and from there, it is estimated the number of neutrons that collide in the whole sphere. The purpose is to obtain the neutron count for different energy bands in a solid field of neutrons, since they have a spectrum ranging from a low to a high energy that can also vary within a particular environment. Wishes to obtain new fields with different sources and moderators materials to be used as new reference fields. Measurements are being conducted for these fields, with the aim of analyzing the variability conditions of the measurement (repeatability and reproducibility) in LEN - Laboratorio de Espectrometria de Neutrons of the LN/LMNRI/IRD. Thus, the spectrometer will be used to improve both the knowledge of the spectrum as the standard of neutrons of the lab, proving that a spectrometry is essential for correct measurement
Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

Energy Technology Data Exchange (ETDEWEB)

Jones, C.G.

1990-08-01

This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs.
Alternative irradiation system for efficiency manganese bath determination

Energy Technology Data Exchange (ETDEWEB)

Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Xavier da Silva, Ademir, E-mail: ademir@con.ufrj.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil)

2010-12-15

An alternative irradiation system, which works with a radionuclide neutron source and manganese sulphate solution volume have been proposed for efficiency determination of a Manganese Bath System (MBS). This irradiation system was designed by simulation with MCNP5 code, considering a californium neutron source in several manganese sulphate volumes and different neutron reflectors. Although its solution specific activity are less than those in nuclear reactors, the simulation results have showed that the irradiation system proposed takes a manganese neutron capture increase up to 200 times when it compared to manganese neutron capture from a MBS whose diameter is about 100 cm. That becomes possible to use those samples for some of the absolute specific activity measuring methods.
Experimental survey of the potential energy surfaces associated with fission

International Nuclear Information System (INIS)

Britt, H.C.

1980-01-01

Progress in the experimental determination of the properties of the potential energy surface associated with fission is reviewed. The importance of nuclear symmetry effects on the calculation of fission widths is demonstrated. Evidence is presented for the fragmentation of the mass-asymmetric second barrier in the thorium region and the axial asymmetric first barrier in the californium region. Detailed analyses of experimental data suggest the presence of two parallel second barriers; the normal mass-asymmetric, axial-symmetric barrier and a slightly higher mass-symmetric, axial-asymmetric barrier. Experimental barrier parameters are determined systematically and compared with calculations from various theoretical models. Techniques for expanding fission probability measurements to higher energies are discussed. (author)
Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

International Nuclear Information System (INIS)

Jones, C.G.

1990-08-01

This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs
Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

International Nuclear Information System (INIS)

Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

1976-10-01

The paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: (1) the spontaneous californium-252 fission neutron spectrum standard field; (2) the thermal-neutron induced uranium-235 fission neutron spectrum standard field; (3) the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN--ΣΣ facilities; (4) the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility (CFRMF); (5) the reference neutron field at the center of the 10 percent enriched uranium metal, cylindrical, fast critical; and (6) the (primary) Intermediate-Energy Standard Neutron Field
Polarimetry of ST LMi (CW1103+254)

Energy Technology Data Exchange (ETDEWEB)

Cropper, M

1986-10-15

White-light simultaneous photometry and linear and circular polarimetry is presented for the AM Her type variable ST LMi. Linear polarization evident throughout the faint phase is tentatively attributed to electron scattering from gas in the accretion column at heights greater than 5 Rsub(wd) above the surface. The values of inclination and magnetic dipole offset are revised to take into account the height and extent of the cyclotron emission regions which are also determined. A model of two closely connected emitting regions is proposed to account for the asymmetries observed in the light curve and polarization data for this and other AM Her systems. The size of the soft X-ray pole cap is calculated. Various parameters such as masses, accretion rates and luminosities are calculated for the system.
16 CFR 254.0 - Scope and application.

Science.gov (United States)

2010-01-01

..., business, or clerical skills, or that is for the purpose of enabling a person to improve his appearance..., marketing, and sale of courses or programs of instruction offered by private vocational or distance...
36 CFR 254.20 - Purpose and scope.

Science.gov (United States)

2010-07-01

..., needed by a community, may be sold under the Townsite Act, for fair market value if those lands would serve indigenous community objectives that outweigh the public objectives and values of retaining the... projects that would change the character of the local community. ...
42 CFR 403.254 - Calculation of premiums.

Science.gov (United States)

2010-10-01

... rate credits. (4) Unearned premium reserve means the portion of gross premiums due that provide for...) Written premiums for the period; plus— (ii) The total premium reserve at the beginning of the period; less— (iii) The total premium reserve at the end of the period. (2) Written premiums in a period means— (i...
42 CFR 422.254 - Submission of bids.

Science.gov (United States)

2010-10-01

... principles. (i) A qualified actuary must certify the plan's actuarial valuation (which may be prepared by others under his or her direction or review). (ii) To be deemed a qualified actuary, the actuary must be a member of the American Academy of Actuaries. (iii) Applicants may use qualified outside actuaries...
Frequency of Tabagism and N34S and P55S Mutations of Serine Peptidase Inhibitor, Kazal Type 1 (SPINK1) and R254W Mutation of Chymotrypsin C (CTRC) in Patients With Chronic Pancreatitis and Controls.

Science.gov (United States)

da Costa, Marianges Zadrozny Gouvêa; Pires, Júlia Glória Lucatelli; Nasser, Paulo Dominguez; Ferreira, Camila da Silva; Teixeira, Ana Cristina de Sá; Paranaguá-Vezozzo, Denise Cerqueira; Guarita, Dulce Reis; Carrilho, Flair José; Ono, Suzane Kioko

2016-10-01

This study aimed to investigate the association between chronic pancreatitis and smoking or genetic mutations. The study sample comprised 148 patients with chronic pancreatitis, 110 chronic alcoholic subjects without pancreatic disease, and 297 volunteer blood donors. Of the patients with chronic pancreatitis, 74% had alcoholic etiology and 26% had idiopathic pancreatitis. The frequency of smoking was 91.4% in patients with alcoholic pancreatitis, higher than 73.3% in alcoholic subjects without pancreatitis (P pancreatitis and blood donors. The N34S mutation of serine peptidase inhibitor, Kazal type 1 (SPINK1) was found in 2.7% of patients with chronic alcoholic pancreatitis, in 5.3% of patients with idiopathic pancreatitis, and in 0.4% of blood donors (P = 0.02). The P55S mutation of SPINK1 was found in 2.7% of patients with alcoholic pancreatitis and in 0.7% of blood donors (P = 0.12). The R254W mutation of chymotrypsin C was found in 0.9% of patients with alcoholic pancreatitis, in 0.9% of chronic alcoholic subjects without pancreatitis, and in 0.4% of blood donors (P = 0.75). In all cases, the mutations were heterozygous. Smoking and the N34S mutation of SPINK1 were positively correlated with chronic pancreatitis.
A tetrameric peptide derived from bovine lactoferricin as a potential therapeutic tool for oral squamous cell carcinoma: A preclinical model.

Directory of Open Access Journals (Sweden)

Víctor Alfonso Solarte

Full Text Available Oral squamous cell carcinoma is the fifth most common epithelial cancer in the world, and its current clinical treatment has both low efficiency and poor selectivity. Cationic amphipathic peptides have been proposed as new drugs for the treatment of different types of cancer. The main goal of the present work was to determine the potential of LfcinB(20-254, a tetrameric peptide based on the core sequence RRWQWR of bovine lactoferricin LfcinB(20-25, for the treatment of OSCC. In brief, OSCC was induced in the buccal pouch of hamsters by applying 7,12-Dimethylbenz(aanthracene, and tumors were treated with one of the following peptides: LfcinB(20-254, LfcinB(20-25, or vehicle (control. Lesions were macroscopically evaluated every two days and both histological and serum IgG assessments were conducted after 5 weeks. The size of the tumors treated with LfcinB(20-254 and LfcinB(20-25 was smaller than that of the control group (46.16±4.41 and 33.92±2.74 mm3 versus 88.77±10.61 mm3, respectively. Also, LfcinB(20-254 caused acellularity in the parenchymal tumor compared with LfcinB(20-25 and vehicle treatments. Furthermore, our results demonstrated that both LfcinB(20-254 and LfcinB(20-25 induced higher degree of apoptosis relative to the untreated tumors (75-86% vs 8%, respectively. Moreover, although the lowest inflammatory response was achieved when LfcinB(20-254 was used, this peptide appeared to induce higher levels of IgG antibodies relative to the vehicle and LfcinB(20-25. In addition the cellular damage and selectivity of the LfcinB(20-254 peptide was evaluated in vitro. These assays showed that LfcinB(20-254 triggers a selective necrotic effect in the carcinoma cell line. Cumulatively, these data indicate that LfcinB(20-254 could be considered as a new therapeutic agent for the treatment of OSCC.
Californium-252 neutron activation analysis of high-level processed nuclear tank waste

International Nuclear Information System (INIS)

Troyer, G.L.; Purcell, M.A.

2000-01-01

The basis for production assessment of the vitrification of Hanford nuclear fuel reprocessing wastes will be high-precision measurements of the elemental sodium content. However, the chemical analysis of both radioactive and nonradioactive components in nuclear waste can be challenged by high radiation dose rates. The dose rates compromise many analytical techniques as well as pose personnel dosimetry risks. In many cases, reduction of dose rates through dilution compromises the precision and sensitivity for certain key components. The use of neutron activation analysis (NAA) provides a method of analysis that avoids the need for dilutions or extensive sample preparation. These waste materials also contain trace quantities of fissionable isotopes, which, through neutron activation, can be estimated by delayed neutron counting of fissioned fragments
Californium-252: isotope for modern radiotherapy of cervix, uterine and vaginal carcinomas

International Nuclear Information System (INIS)

Maruyama, J.; Beach, J.L.; Nagell, J.R. van

1984-01-01

Cf-252 is an isotope that can easily be afterloaded into available gynecological applicators and used for bulky cervix, uterus or vaginal cancer therapy. It is economical, time and cost effective in use, and can be applied to the therapy of many patients throughout the world. It is more effective for neutron therapy than machine fast neutron therapy and is the only form of neutron therapy producing consistent complication-free 5-year cure of advanced cancers currently available. Cf-252 is an isotope for modern gynecological tumor therapy for the future. Isodose curves for Cf-252 implants revealed dose distributions conforming well to tumor. (orig.) [de
ORF Alignment: NC_005090 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available YYWRICASKGVKILLLGEYVLNLFFKEIENLPSNMVAEQSE 60 ... Query: 121 FANSLPKSPKNPPVFEIDGIKIAPLFGYEAHFDEFWLKFKRLDVDLALIPSAS...TFDSLNR 180 ... FANSLPKSPKNPPVFEIDGIKIAPLFGYEAHFDEFWLKFKRLDVDLALIPSASTFD...SLNR Sbjct: 121 FANSLPKSPKNPPVFEIDGIKIAPLFGYEAHFDEFWLKFKRLDVDLALIPSASTFDSLNR 180 ... Query: 241 XXXXXXXXXIRRSW 254 ... IRRSW Sbjct: 241 ELDQGYLEEIRRSW 254
An Investigation of the Performance of a Ribbon and Small Planar Magnetic Transducer, Made for Use in Air, as an Underwater Acoustic Velocity Sensor

Science.gov (United States)

2016-09-01

excitation of a sensor by independently calculable means may be possible. For example, pistonphones and electrostatic actuators are common devices for...the model RE-254, shown in Figure 17, which is manufactured by Audio Components DIY in Latvia. The RE-254 employs an aluminum foil, 2.5 microns thick...Aug. 7, 2016. [8] RE-254 ribbon microphone motor for DIY mic project. (n.d.); DiY Audio Components. [Online]. Available: http
Dissolved organic carbon in coral-reef lagoons, by high temperature catalytic oxidation and UV spectrometry

Science.gov (United States)

Pagès, Jean; Torréton, Jean-Pascal; Sempéré, Richard

1997-06-01

Two surveys were carried out on ten atolls in the Tuamotu archipelago (French Polynesia, Pacific Ocean). In vitro UV (250-400 nm) spectra of water samples gave absorption at 254 nm, A 254, and spectrum slope, S ⋆ (computed from In A λ versus λ).These two descriptors are negatively correlated, and data points are arrayed along a hyperbola spanned between an oceanic pole (high S ⋆, low A 254) and a confined pole (low 5 ⋆, high A 254). Dissolved organic carbon (DOC) concentrations, [C], as assessed by HTCO, exhibit a narrow range (0.7-1.0 mg C.L -1 for most lagoons) contrasting with the wide diversity of optical characteristics. [C] and A 254 are positively correlated, with a significant intercept (0.5 mg C.L -1) representing non-chromophoric DOC. Carbon-specific absorption, ɛ 254 increases (from 0.4 to 1.3 m 2.g -1) with increasing [C], mainly according to the literature) owing to increased average molecular weight (MW) of the chromophoric DOC fraction, which also lowers S ⋆. Our optical data thus illustrate a gradient of confinement (or residence time) that corresponds to a continuum in DOC nature, especially in MW and hence in bioavailability. Optical methods are confirmed as quick and effective means of assessing DOM distribution.
Degradation kinetics and mechanism of β-lactam antibiotics by the activation of H2O2 and Na2S2O8 under UV-254 nm irradiation

International Nuclear Information System (INIS)

He, Xuexiang; Mezyk, Stephen P.; Michael, Irene; Fatta-Kassinos, Despo; Dionysiou, Dionysios D.

2014-01-01

Graphical abstract: - Highlights: • Removal efficiency was comparable at different UV fluence rates but same fluence. • Reducing pH to 3 or 2 did not inhibit the removal of nitrobenzene by UV/S 2 O 8 2− . • 1.84 × 10 −14 M [HO • ] ss and 3.10 × 10 −13 M [SO 4 • − ] ss in UV/S 2 O 8 2− were estimated. • HO • reacted faster with the β-lactams than SO 4 • − but sharing similar byproducts. • Transformation pathways included hydroxylation, hydrolysis and decarboxylation. - Abstract: The extensive production and usage of antibiotics have led to an increasing occurrence of antibiotic residuals in various aquatic compartments, presenting a significant threat to both ecosystem and human health. This study investigated the degradation of selected β-lactam antibiotics (penicillins: ampicillin, penicillin V, and piperacillin; cephalosporin: cephalothin) by UV-254 nm activated H 2 O 2 and S 2 O 8 2− photochemical processes. The UV irradiation alone resulted in various degrees of direct photolysis of the antibiotics; while the addition of the oxidants improved significantly the removal efficiency. The steady-state radical concentrations were estimated, revealing a non-negligible contribution of hydroxyl radicals in the UV/S 2 O 8 2− system. Mineralization of the β-lactams could be achieved at high UV fluence, with a slow formation of SO 4 2− and a much lower elimination of total organic carbon (TOC). The transformation mechanisms were also investigated showing the main reaction pathways of hydroxylation (+16 Da) at the aromatic ring and/or the sulfur atom, hydrolysis (+18 Da) at the β-lactam ring and decarboxylation (–44 Da) for the three penicillins. Oxidation of amine group was also observed for ampicillin. This study suggests that UV/H 2 O 2 and UV/S 2 O 8 2− advanced oxidation processes (AOPs) are capable of degrading β-lactam antibiotics decreasing consequently the antibiotic activity of treated waters
A new type-B cask design for transporting 252Cf

International Nuclear Information System (INIS)

Simmons, C.M.

2000-01-01

A project to design, certify, and build a new US Department of Energy (DOE) Type B container for transporting >5 mg of 252 Cf is more than halfway to completion. This project was necessitated by the fact that the existing Oak Ridge National Laboratory (ORNL) Type B containers were designed and built many years ago and thus do not have the records and supporting data that current regulations require. Once the new cask is available, it will replace the existing Type B containers. The cask design is driven by the unique properties of 252 Cf, which is a very intense spontaneous fission neutron source and necessitates a large amount of neutron shielding. The cask is designed to contain up to 60 mg of 252 Cf in the form of californium oxide or californium oxysulfate, in pellet, wire, or sintered material forms that are sealed inside small special-form capsules. The new cask will be capable of all modes of transport (land, sea, and air). The ORNL team, composed of technical and purchasing personnel and using rigorous selection criteria, chose NAC, International (NAC), as the subcontractor for the project. In January 1997, NAC started work on developing the conceptual design and performing the analyses. The original design concept was for a tungsten alloy gamma shield surrounded by two concentric shells of NS-4-FR neutron shield material. A visit to US Nuclear Regulatory Commission (NRC) regulators in November 1997 to present the conceptual design for their comments resulted in a design modification when the question of potential straight-line cracking in the NS-4-FR neutron shield material arose. NAC's modified design includes offset, wedgelike segments of the neutron shield material. The new geometry eliminates concerns about straight-line cracking but increases the weight of the packaging and makes the fabrication more complex. NAC has now completed the cask design and performed the analyses (shielding, structural, thermal, etc.) necessary to certify the cask. The cask

Physical-chemical studies of transuranium elements: Progress report for the period April 1, 1985-March 31, 1988

International Nuclear Information System (INIS)

Peterson, J.R.

1987-01-01

New knowledge is being accumulated in the role of the 5f electrons in the bonding in actinide elements and compounds, the relationships of metallic structures to metallic valence and radius, the extent and magnitude of the actinide contraction, the magnetic, thermodynamic, spectroscopic, and crystallographic properties of these materials as related to general theories, the effect of self-irradiation on chemical and physical properties, the chemical and physical consequences of radioactive decay in the bulk-phase solid state, and in general, the range of validity of the actinide hypothesis. Separate reports are given on: spectrophotometric studies of Cf(III) ions in lanthanide trihalide hosts, new ternary transplutonium chalcogenide halides, Raman spectrometric studies of lanthanide trihalides as function of T or P, and solution calorimetry of californium halides
Radionuclide toxicity

International Nuclear Information System (INIS)

Galle, P.

1982-01-01

The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr
Fabrication of 50-mg 252Cf neutron sources for the FDA [Food and Drug Administration] activation analysis facility

International Nuclear Information System (INIS)

Bigelow, J.E.; Cagle, E.B.; Knauer, J.B.

1987-01-01

The Transuranium Processing Plant (TPP) at ORNL has been requested by the Food and Drug Administration (FDA) to furnish 200 mg of 252 Cf for use in their new activation analysis facility. This paper discusses the procedure to be employed in fabricating the californium into four neutron sources, each containing a nominal 50-mg of 252 Cf. The ORNL Model LSD (Large, Stainless steel, Doubly encapsulated) neutron source consists of a 6.33-mm-diam aluminum pellet doubly encapsulated in Type 304L stainless steel. The pellet is comprised of an aluminum tube holding Cf 2 O 2 SO 4 microspheres confined by pressed aluminum powder. The microspheres are prepared in a separate vessel and then transferred into the specially designed aluminum tube prior to pressing
Adaptive changes in NAD+ metabolism in ultraviolet light-irradiated murine lymphoma cells

International Nuclear Information System (INIS)

Kleczkowska, H.E.; Szumiel, I.; Althaus, F.R.

1990-01-01

We have determined the ability of UV254nm-irradiated murine lymphoma cells to adapt their NAD+ metabolism to the increased NAD+ consumption for the poly ADP-ribosylation of chromatin proteins. Two murine lymphoma sublines with differential UV-sensitivity and poly(ADP-ribose) turnover were used as a model system. The first subline, designated LY-R is UV254nm-sensitive and tumorigenic in DBA/2 mice. The second subline, LY-S is UV254nm-resistant and nontumorigenic. Following treatment of these cells with 2 mM benzamide, an inhibitor of the NAD(+)-utilizing enzyme poly(ADP-ribose) polymerase, NAD+ levels slowly increased up to about 160% of control levels after 3 hours. When benzamide was added to these cultures 20 min after UV254nm irradiation, a dramatic transient increase of NAD+ levels was observed within 4 min in LY-R cells and more moderately in LY-S cells. At later times after UV254nm irradiation, the NAD+ levels increased in both sublines reaching up to 200% of the concentrations prior to benzamide treatment. These results demonstrate an adaptative response of NAD+ metabolism to UV254nm irradiation. In parallel, we observed a differential repartitioning of ADP-ribosyl residues between the NAD+ and poly(ADP-ribose) pools of LY-R and LY-S cells that correlates with the differential UV sensitivity of these cells
Dimeric Structure of the Blue Light Sensor Protein Photozipper in the Active State.

Science.gov (United States)

Ozeki, Kohei; Tsukuno, Hiroyuki; Nagashima, Hiroki; Hisatomi, Osamu; Mino, Hiroyuki

2018-02-06

The light oxygen voltage-sensing (LOV) domain plays a crucial role in blue light (BL) sensing in plants and microorganisms. LOV domains are usually associated with the effector domains and regulate the activities of effector domains in a BL-dependent manner. Photozipper (PZ) is monomeric in the dark state. BL induces reversible dimerization of PZ and subsequently increases its affinity for the target DNA sequence. In this study, we report the analyses of PZ by pulsed electron-electron double resonance (PELDOR). The neutral flavin radical was formed by BL illumination in the presence of dithiothreitol in the LOV-C254S (without the bZIP domain) and PZ-C254S mutants, where the cysteine residue responsible for adduct formation was replaced with serine. The magnetic dipole interactions of 3 MHz between the neutral radicals were detected in both LOV-C254S and PZ-C254S, indicating that these mutants are dimeric in the radical state. The PELDOR simulation showed that the distance between the radical pair is close to that estimated from the dimeric crystal structure in the "light state" [Heintz, U., and Schlichting, I. (2016) eLife 5, e11860], suggesting that in the radical state, LOV domains in PZ-C254S form a dimer similar to that of LOV-C254S, which lacks the bZIP domain.
Fiscal consequences of monetary integration within the common economic area: the case of Belarus, Kazakhstan and Russia

Czech Academy of Sciences Publication Activity Database

Uzagalieva, Ainura

-, č. 254 (2005), s. 1-46 ISSN 1211-3298 Institutional research plan: CEZ:AV0Z70850503 Keywords : seigniorage * monetary integration * transition economies Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp254.pdf
Determination of the average number of neutrons per fission event for californium-252

International Nuclear Information System (INIS)

Aleksandrov, B.M.; Belov, L.M.; Drapchinskij, L.V.

1982-01-01

By means of a separate determination of neutron yields and fission event rates, the value of #betta#-bar( 252 Cf) has been measured for a series of new high-purity sources. The improved quality of the source active layers has reduced the error in determining the fission rate to 0.35%. The value obtained for #betta#-bar( 252 Cf) is 3.747+-0.036. A description is given of the design and the parameters of a spherical manganese bath in which the work on refining the value of #betta#-bar( 252 Cf) will be continued. (author)
Chromatographic cation exchange separation of decigram quantities of californium and other transplutonium elements

Energy Technology Data Exchange (ETDEWEB)

Benker, D.E.; Chattin, F.R.; Collins, E.D.; Knauer, J.B.; Orr, P.B.; Ross, R.G.; Wiggins, J.T.

1980-01-01

Decigram quantities of highly radioactive transplutonium elements are routinely partitioned at TRU by chromatographic elution from cation resin using AHIB eluent. By using two high-pressure ion exchange columns, a small one for the initial loading of the feed and a large one for the elution, batch runs containing up to 200 mg of /sup 252/Cf can be made in about 5 hours (2 hours to load the feed and 3 hours for the elution). The number of effluent product fractions and the amount of actinides that must be collected in intermediate fractions are minimized by monitoring response from a flow-through alpha-detector. This process has been reliable and relatively easy to operate, and will continue to be used for partitioning transplutonium elements at TRU.
Dicty_cDB: VFM254 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available (All Frames) Frame A: ---xxxxxxxxxxxxxxxxvxxxxxxxrxxxxxxxxxxxxxxxkvxxxxxkxxfxxvxnx xmvvlxxittfkrnplsi*ssd*ev...vckflskpslvrllhxklkvlitlrmlkpksktkk vfhqinnvsfspvnnwrmvvlslittfkrnplsi*fsd*evvckfl*klslvkplhsklk vvttlrm*kqkfktkkvshq Frame B: ---xxx...xxxxxxxxxxxxwxxxxxxsxgxxxxxxcxxxxxxxxryxxxxxxxxfxw*xix x
Dicty_cDB: SHL254 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available IXIXIIX*xfyxilk*lviivshs lxpyisxxckgyd*ixxklfitrfmmvvxvhgqinhchlvvrasqvwwcfxsclqcxxcs gkecxiqrllvvfvkrygflkx...iihn**lllh*hnnkliq*lyhh *enqmllkhgwkl*ecv--- ---XLXPVQVXEPNFQMXXFHFXLXLETXFXXDFRRIXIXIIX*xfyxilk*lviivshs lxpyisxxc
40 CFR 180.254 - Carbofuran; tolerances for residues.

Science.gov (United States)

2010-07-01

...) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances... than 1 ppm is carbamates) 2 12/31/09 Pumpkin (of which not more than 0.6 ppm is carbamates) 0.8 12/31...
7 CFR 1710.254 - Alternative sources of power.

Science.gov (United States)

2010-01-01

... proposals on an economic, present-value basis, giving consideration to cost-effectiveness, reliability of... reliability problems. (Approved by the Office of Management and Budget under control number 0572-0032) [57 FR...
Transuranium Processing Plant semiannual report of production, status, and plans for period ending June 30, 1975

International Nuclear Information System (INIS)

King, L.J.; Bigelow, J.E.; Collins, E.D.

1976-03-01

During the period January 1, 1975, through June 30, 1975, the following amounts of transuranium elements were recovered from 22 irradiated HFIR targets: 2g 243 Am, 59 g 244 Cm, 51 mg 249 Bk, 465 mg 252 Cf, 2.5 mg 253 Es, and 1.4 pg 257 Fm. In addition, 45 mg of high-purity 248 Cm was operated from 252 Cf which had been recovered and purified during earlier periods, and 56 mg of a lower-quality 248 Cm was separated from californium purification rework solutions. Five HFIR targets, each containing approximately 9 g of actinides (predominantly curium), were fabricated. A new long-term projection showed that 252 Cf production in the TRU-HFIR complex could increase to as much as 2.5 g/year. During the next 18 months, we expect to recover totals of 46 mg of 249 Bk, 520 mg of 252 Cf, 2.0 mg of 253 Es (in a mixture of isotopes), 220 μg of high-purity 253 Es, and 1.6 pg of 257 Fm. We also expect to obtain 125 mg of high-purity 248 Cm from purified californium now in storage. There are no plans to process any of the remaining SRP Pu-Al tubes or to irradiate any plutonium targets in the HFIR; thus, we do not expect to recover any 244 Pu. Two neutron sources were fabricated, bringing the total fabricated to 77. Two sources that had been used previously in various projects were returned to the TRU inventory and are available for reassignment. In special projects, we (1) produced about 1 mg of 250 Cf by irradiation of 249 Bk in HFIR rabbits, and (2) processed some irradiated 248 Cm samples and obtained yield and isotopic composition data for use in determining the capture cross section of 249 Cm in the HFIR. The values that are currently being used for transuranium element decay data and for cross-section data in planning irradiation-processing cycles, calculating production forecasts, and assaying products are tabulated in the Appendix
Swelling of cross-linked polymers: interpretations and misinterpretations

Czech Academy of Sciences Publication Activity Database

Dušek, Karel; Dušková-Smrčková, Miroslava

2017-01-01

Roč. 254, 20 August (2017), s. 102 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] Institutional support: RVO:61389013 Keywords : swelling * cross-linked polymer Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science
Smart ampholytic ABC block copolypeptide

Czech Academy of Sciences Publication Activity Database

Schlaad, H.; Sun, J.; Černoch, Peter; Ruokolainen, J.

2017-01-01

Roč. 254, 20 August (2017), s. 79 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] Institutional support: RVO:61389013 Keywords : block copolypeptide * smart ampholytic Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science
Decay Curves and Half-Lives of Gamma-Emitting States from a Study of Prompt Fission Gamma Radiation

Energy Technology Data Exchange (ETDEWEB)

Albinsson, H [Chalmers Univ. of Technology, Goeteborg (SE)

1971-04-15

Measurements were made on the time distributions of the prompt gamma radiation emitted from fragments in the thermal-neutron induced fission of 235U. The gamma radiation emitted during different time intervals after the fission event was studied with the help of a collimator, the position of which was changed along the path of the fragments. In this way decay curves were obtained from which half-lives could be estimated. Time components with half-lives of 7.5, 18 and 60 ps were found and their relative intensities were calculated. Half-lives and associated intensities are in good agreement with earlier data from uranium and californium fission. Problems involved in this type of study are discussed. The collimator technique has proved to be effective for determination of half lives down to less than 10 ps
Neutron radiography for nondestructive testing

International Nuclear Information System (INIS)

John, J.

1979-01-01

Neutron radiography is similar to X-ray inspection in that both depend upon use of radiation that penetrates some materials and is absorbed by others to provide a contrast image of conditions not readily available for visual inspection. X-rays are absorbed by dense materials, such as metals, whereas neutrons readily penetrate metals, but are absorbed by materials containing hydrogen. The neutron radiography has been successfully applied to a number of inspection situations. These include the inspection of explosives, advanced composites, adhesively bonded structures and a number of aircraft engine components. With the availability of Californium-252, it has become feasible to construct mobile neutron radiography systems suitable for field use. Such systems have been used for in-situ inspection of flight line aircraft, particularly to locate and measure hidden corrosion
The CARIBU EBIS control and synchronization system

Science.gov (United States)

Dickerson, Clayton; Peters, Christopher

2015-01-01

The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. The control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.
Reliability of semiconductor and gas-filled diodes for over-voltage protection exposed to ionizing radiation

Directory of Open Access Journals (Sweden)

Stanković Koviljka

2009-01-01

Full Text Available The wide-spread use of semiconductor and gas-filled diodes for non-linear over-voltage protection results in a variety of possible working conditions. It is therefore essential to have a thorough insight into their reliability in exploitation environments which imply exposure to ionizing radiation. The aim of this paper is to investigate the influence of irradiation on over-voltage diode characteristics by exposing the diodes to californium-252 combined neutron/gamma radiation field. The irradiation of semiconductor over-voltage diodes causes severe degradation of their protection characteristics. On the other hand, gas-filled over-voltage diodes exhibit a temporal improvement of performance. The results are presented with the accompanying theoretical interpretations of the observed changes in over-voltage diode behaviour, based on the interaction of radiation with materials constituting the diodes.
Designing on-line analyzer for coal on belt conveyor using neutron activation technique

International Nuclear Information System (INIS)

Rony Djokorayono; Agus Cahyono

2014-01-01

Basic design of on-line analyzer for coal on belt conveyor using neutron activation technique has been carried out. Compared with sampling technique, this neutron activation technique has some advantages in term of analysis accuracy and time. The design activities performed include the establishment of design requirements, functional requirements, technical requirements, technical specification, detection sub-system design, data acquisition subsystem design, and operator computer console design. This program will use Nal(Tl) scintillation detector to detect gamma-rays emitted by elements in coal due to neutron activation of a neutron source, "2"5"2Cf (Californium-252). This basic design of on-line analyzer for coal on belt conveyor using neutron activation technique should be followed up with the development of detailed design, prototype construction, and field testing. (author)

Nuclear assay of coal. Volume 8. Continuous nuclear assay of coal (CONAC). Final report

International Nuclear Information System (INIS)

Lagarias, J.; Irminger, P.; Dodson, W.

1979-01-01

Using californium-252 as a source of exciting neutrons, prompt gamma photons emitted by elemental nuclei in the coal have been measured using several detectors, including sodium-iodide and germanium-lithium. Several coal types, including bituminous, subbituminous lignite and anthracite were crushed to various top sizes and analyzed carefully by traditional ASTM wet chemistry techniques at two or three different laboratories. The elements (sulfur, hydrogen, carbon, aluminum, silicon, iron, calcium, sodium, nitrogen, and chlorine) were determined by prompt neutron activations and the quantities compared with those of the wet chemical analyses. Since satisfactory correlation has been obtained at bench-scale level using 100 to 200 kG samples, an apparatus has been designed to analyze a coal stream of up to 50 ton/hour, at an electric power generating station
Neutron dosimetry and spectrometry with Bonner spheres. Working out a log-normal reference matrix

International Nuclear Information System (INIS)

Zaborowski, Henrick.

1981-11-01

From the experimental and theoretical studies made upon the BONNER's spheres System with a I 6 Li(Eu) crystal and with a miniaturized 3 He counter we get the normalized energy response functions R*sub(i)(E). This normalization is obtained by the mathematization of the Resolution Function R*(i,E) in the Log-Normal distribution hypothesis to mono energetic neutrons given in April 1976 to the International Symposium on Californium 252. The fit of the Log-Normal Hypothesis with the experimental and Theoretical data is very satisfactory. The parameter's tabulated values allow a precise interpolation, at all energies between 0.4 eV and 15 MeV and for all spheres diameters between 2 and 12 inches, of the discretized R*sub(ij) Reference Matrix for the applications to neutron dosimetry and spectrometry [fr
The CARIBU EBIS control and synchronization system

Energy Technology Data Exchange (ETDEWEB)

Dickerson, Clayton, E-mail: cdickerson@anl.gov; Peters, Christopher, E-mail: cdickerson@anl.gov [Argonne National Laboratory, Argonne, IL 60439 (United States)

2015-01-09

The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. The control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.
Chemical consequences of radioactive decay. 1. Study of 249Cf ingrowth into crystalline 249BkBr3: a new crystalline phase of CfBr3

International Nuclear Information System (INIS)

Young, J.P.; Haire, R.G.; Peterson, J.R.; Ensor, D.D.; Fellows, R.L.

1980-01-01

Spectrophotometric and x-ray powder diffraction methods have been applied to a study of the ingrowth of californium-249 by β - decay of berkelium-249 in crystalline 249 BkBr 3 . It was found that the Cf daughter grows in with the same oxidation state and crystal structure as the parent. Thus, six-coordinate BkBr 3 (AlCl 3 -type monoclinic structure) generates six-coordinate CfBr 3 , and eight-coordinate BkBr 3 (PuBr 3 -type orthorhombic structure) generates eight-coordinate CfBr 3 , a previously unknown form of CfBr 3 . It was also found that the daughter Cf(III) in the BkBr 3 parent compound can be reduced to Cf(II) by treatment with H 2 , as it can in pure CfBr 3 . 5 figures
Provenance and composition study on Terengganu inscribed stone using in-situ nuclear technology

International Nuclear Information System (INIS)

Jaafar Abdullah; Roslan Yahya; Hearie Hassan; Engku Mohd Fahmi Engku Chik; Mohamad Rabaie Shari; Airwan Affendi Mahmood; Abdul Quddoss Abu Bakar; Ainul Mardhiah Terry

2012-01-01

This paper focused on the analysis of trace elements and provenance study of the Inscribed Stone of Terengganu (BBPT) using Neutron-induced Prompt Gamma-Ray Techniques (NIPGAT). In this study, portable NIPGAT system was designed and developed by using volume-based measurement. It is a nondestructive testing technique for the samples. This system uses low activity of isotopic neutron radioactive source from californium-252 (Cf-252) as an irradiation source. Gamma ray spectroscopy as well as specialized computer software has been utilized to conduct the research. The study has determined that the stone was a dolerite stone based on the composition of the stone elements. Although most of the scientific data for this study have been collected, this project is still running to complete the scope of provenance study. (author)
Nuclear fission and the transuranium elements

International Nuclear Information System (INIS)

Seaborg, G.T.

1989-02-01

Many of the transuranium elements are produced and isolated in large quantities through the use of neutrons furnished by nuclear fission reactions: plutonium (atomic number 94) in ton quantities; neptunium (93), americium (95), and curium (96) in kilogram quantities; berkelium (97) in 100 milligram quantities; californium (98) in gram quantities; and einsteinium (99) in milligram quantities. Transuranium isotopes have found many practical applications---as nuclear fuel for the large-scale generation of electricity, as compact, long-lived power sources for use in space exploration, as means for diagnosis and treatment in the medical area, and as tools in numerous industrial processes. Of particular interest is the unusual chemistry and impact of these heaviest elements on the periodic table. This account will feature these aspects. 9 refs., 5 figs
Nuclear fission and the transuranium elements

Energy Technology Data Exchange (ETDEWEB)

Seaborg, G.T.

1989-02-01

Many of the transuranium elements are produced and isolated in large quantities through the use of neutrons furnished by nuclear fission reactions: plutonium (atomic number 94) in ton quantities; neptunium (93), americium (95), and curium (96) in kilogram quantities; berkelium (97) in 100 milligram quantities; californium (98) in gram quantities; and einsteinium (99) in milligram quantities. Transuranium isotopes have found many practical applications---as nuclear fuel for the large-scale generation of electricity, as compact, long-lived power sources for use in space exploration, as means for diagnosis and treatment in the medical area, and as tools in numerous industrial processes. Of particular interest is the unusual chemistry and impact of these heaviest elements on the periodic table. This account will feature these aspects. 9 refs., 5 figs.
Interpenetrating polymer network hydrogels based on poly(2-hydroxyethyl methacrylate): morphology effects on formation, swelling, optical, and mechanical properties

Czech Academy of Sciences Publication Activity Database

Dušková-Smrčková, Miroslava; Sadakbayeva, Zhansaya; Steinhart, Miloš; Šturcová, Adriana; Pfleger, Jiří; Dušek, Karel

2017-01-01

Roč. 254, 20 August (2017), s. 40 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] Institutional support: RVO:61389013 Keywords : IPN * poly(2-hydroxyethyl methacrylate) * hydrogel Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science
Pilot investigation of two-stage biofiltration for removal of natural organic matter in drinking water treatment.

Science.gov (United States)

Fu, Jie; Lee, Wan-Ning; Coleman, Clark; Meyer, Melissa; Carter, Jason; Nowack, Kirk; Huang, Ching-Hua

2017-01-01

A pilot study employing two parallel trains of two-stage biofiltration, i.e., a sand/anthracite (SA) biofilter followed by a biologically-active granular activated carbon (GAC) contactor, was conducted to test the efficiency, feasibility and stability of biofiltration for removing natural organic matter (NOM) after coagulation in a drinking water treatment plant. Results showed the biofiltration process could effectively remove turbidity (24% of dissolved organic carbon (DOC), >57% of UV 254 , and >44% of SUVA 254 ), where the SA biofilters showed a strong capacity for turbidity removal, while the GAC contactors played the dominant role in NOM removal. The vertical profile of water quality in the GAC contactors indicated the middle-upper portion was the critical zone for the removal of NOM, where relatively higher adsorption and enhanced biological removal were afforded. Fluorescence excitation-emission matrix (EEM) analysis of NOM showed that the GAC contactors effectively decreased the content of humic-like component, while protein-like component was refractory for the biofiltration process. Nutrients (NH 4 -N and PO 4 -P) supplementation applied upstream of one of the two-stage biofiltration trains (called engineered biofiltration) stimulated the growth of microorganisms, and showed a modest effect on promoting the biological removal of small non-aromatic compositions in NOM. Redundancy analysis (RDA) indicated influent UV 254 was the most explanatory water quality parameter for GAC contactors' treatment performance, and a high load of UV 254 would result in significantly reduced removals of UV 254 and SUVA 254 . Copyright © 2016 Elsevier Ltd. All rights reserved.
78 FR 9056 - Agency Information Collection Activities: Proposed Collection; Comment Request

Science.gov (United States)

2013-02-07

... agent/brokers provided during training will be used to record their training history through CMS LMS... small business health options plan (SHOP) employers/employees through the Exchange. Additionally, CMS...: Private Sector: Business or other for-profits; Number of Respondents: 254,095; Total Annual Responses: 254...
Communications dated 15 and 22 March 1994 received from the permanent mission of South Africa to the International Atomic Energy Agency

International Nuclear Information System (INIS)

1994-01-01

The Director General received notes verbales dated 15 and 22 March 1994 from the Permanent Mission of South Africa providing information on the nuclear export policies and practices of the Government of South Africa. These notes verbales contain, in their attachments, copies of the relevant legislation and other documentation pertaining to South Africa's policy to act in accordance with the provisions of INFCIRC/254/Rev.1/Part 1 and INFCIRC/254/Rev.1/Part 1/Mod.1 and INFCIRC/254/Rev.1/Part 2 as amended. The documents are available on request from the Secretariat of the IAEA
Modification of a hydrophobic layer by a point mutation in syntaxin 1A regulates the rate of synaptic vesicle fusion.

Directory of Open Access Journals (Sweden)

Robert D Lagow

2007-04-01

Full Text Available Both constitutive secretion and Ca(2+-regulated exocytosis require the assembly of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE complexes. At present, little is known about how the SNARE complexes mediating these two distinct pathways differ in structure. Using the Drosophila neuromuscular synapse as a model, we show that a mutation modifying a hydrophobic layer in syntaxin 1A regulates the rate of vesicle fusion. Syntaxin 1A molecules share a highly conserved threonine in the C-terminal +7 layer near the transmembrane domain. Mutation of this threonine to isoleucine results in a structural change that more closely resembles those found in syntaxins ascribed to the constitutive secretory pathway. Flies carrying the I254 mutant protein have increased levels of SNARE complexes and dramatically enhanced rate of both constitutive and evoked vesicle fusion. In contrast, overexpression of the T254 wild-type protein in neurons reduces vesicle fusion only in the I254 mutant background. These results are consistent with molecular dynamics simulations of the SNARE core complex, suggesting that T254 serves as an internal brake to dampen SNARE zippering and impede vesicle fusion, whereas I254 favors fusion by enhancing intermolecular interaction within the SNARE core complex.
ORF Alignment: NC_003305 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_003305 gi|17938192 >1v7zA 16 254 17 254 3e-36 ... ref|NP_534981.1| creatinine amid...ohydrolase [Agrobacterium tumefaciens str. C58] ... gb|AAL45297.1| creatinine amidohydrolase [Agrobac... C58] pir||AC3110 ... creatinine amidohydrolase [imported] - Agrobacterium
ORF Alignment: NC_003063 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_003063 gi|15890482 >1v7zA 16 254 17 254 3e-36 ... ref|NP_534981.1| creatinine amid...ohydrolase [Agrobacterium tumefaciens str. C58] ... gb|AAL45297.1| creatinine amidohydrolase [Agrobac... C58] pir||AC3110 ... creatinine amidohydrolase [imported] - Agrobacterium
Predicting trace organic compound breakthrough in granular activated carbon using fluorescence and UV absorbance as surrogates.

Science.gov (United States)

Anumol, Tarun; Sgroi, Massimiliano; Park, Minkyu; Roccaro, Paolo; Snyder, Shane A

2015-06-01

This study investigated the applicability of bulk organic parameters like dissolved organic carbon (DOC), UV absorbance at 254 nm (UV254), and total fluorescence (TF) to act as surrogates in predicting trace organic compound (TOrC) removal by granular activated carbon in water reuse applications. Using rapid small-scale column testing, empirical linear correlations for thirteen TOrCs were determined with DOC, UV254, and TF in four wastewater effluents. Linear correlations (R(2) > 0.7) were obtained for eight TOrCs in each water quality in the UV254 model, while ten TOrCs had R(2) > 0.7 in the TF model. Conversely, DOC was shown to be a poor surrogate for TOrC breakthrough prediction. When the data from all four water qualities was combined, good linear correlations were still obtained with TF having higher R(2) than UV254 especially for TOrCs with log Dow>1. Excellent linear relationship (R(2) > 0.9) between log Dow and the removal of TOrC at 0% surrogate removal (y-intercept) were obtained for the five neutral TOrCs tested in this study. Positively charged TOrCs had enhanced removals due to electrostatic interactions with negatively charged GAC that caused them to deviate from removals that would be expected with their log Dow. Application of the empirical linear correlation models to full-scale samples provided good results for six of seven TOrCs (except meprobamate) tested when comparing predicted TOrC removal by UV254 and TF with actual removals for GAC in all the five samples tested. Surrogate predictions using UV254 and TF provide valuable tools for rapid or on-line monitoring of GAC performance and can result in cost savings by extended GAC run times as compared to using DOC breakthrough to trigger regeneration or replacement. Copyright © 2015 Elsevier Ltd. All rights reserved.
Book Review: John M. Hobson and Leonard Seabrooke (2007) (eds) Everyday Politics of the World Economy

DEFF Research Database (Denmark)

Strange, Michael Stewart

2009-01-01

Book Review: John M. Hobson and Leonard Seabrooke (2007) (eds) Everyday Politics of the World Economy (Cambridge: Cambridge University Press), 254pp. Udgivelsesdato: 2009......Book Review: John M. Hobson and Leonard Seabrooke (2007) (eds) Everyday Politics of the World Economy (Cambridge: Cambridge University Press), 254pp. Udgivelsesdato: 2009...
Utilization of radiation facilities at TNRC for shielding researches and related topics

Energy Technology Data Exchange (ETDEWEB)

Akki, T S [Physics Department, Nuclear Physics and Radiation Shielding Division Tajura Nuclear Research Center, Tripoli (Libyan Arab Jamahiriya)

1997-12-31

This paper presents the running shielding research activities at Tajura Nuclear research center. The main area of researches are concentrated on the investigation of different types of concrete made from local materials such as conventional concrete, Magnetite-Limonite concrete, and heat resistant concrete. The measuring techniques used were neutron-gamma spectrometry, and activation foils. The measurements were performed using collimated beam of reactor neutrons emitted from one of the horizontal channels, as well as from californium-252 neutron source. The transmitted neutron spectra through concrete barriers of different thicknesses were measured by a scintillation spectrometer with NE-213 liquid organic scintillator. A non-destructive testing of some reactor materials were also carried out using neutron and gamma ray computerized tomography technique (CT). Some experiments were also carried out related to measurements of neutron depth dose distributions inside tissue equivalent materials. 10 figs.
Dust grain charges in a nuclear-track plasma and the formation of dynamic vortex dust structures

International Nuclear Information System (INIS)

Rykov, V.A.; Khudyakov, A.V.; Filinov, V.S.; Vladimirov, V.I.; Deputatova, L.V.; Krutov, D.V.; Nefedov, A.P.; Fortov, V.E.

2002-01-01

Results are presented from Monte Carlo calculations of the electric charge of dust grains in a plasma produced during the slowing down of the radioactive decay products of californium nuclei in neon. The dust grain charging is explained for the first time as being due to the drift of electrons and ions in an external electric field. It is shown that the charges of the grains depend on their coordinates and strongly fluctuate with time. The time-averaged grain charges agree with the experimental data obtained on ordered liquidlike dust structures in a nuclear-track plasma. The time-averaged dust grain charges are used to carry out computer modeling of the formation of dynamic vortex structures observed in experiments. Evidence is obtained of the fact that the electrostatic forces experienced by the dust grains are potential in character
Transuranic biokinetic parameters for marine invertebrates--a review.

Science.gov (United States)

Ryan, T P

2002-04-01

A catalogue of biokinetic parameters for the transuranic elements plutonium, americium, curium, neptunium, and californium in marine invertebrates is presented. The parameters considered are: the seawater-animal concentration factor (CF); the sediment-animal concentration ratio (CR); transuranic assimilation efficiency; transuranic tissue distribution and transuranic elimination rates. With respect to the seawater-animal CF, authors differ considerably on how they define this parameter and a seven-point reporting system is suggested. Transuranic uptake from sediment by animals is characterised by low CRs. The assimilation efficiencies of transuranic elements in marine invertebrates are high compared to vertebrates and mammals in general and the distribution of transuranics within the body tissue of an animal is dependent on the uptake path. The elimination of transuranics from most species examined conformed to a standard biphasic exponential model though some examples with three elimination phases were identified.
Off-line commissioning of EBIS and plans for its integration into ATLAS and CARIBU

Energy Technology Data Exchange (ETDEWEB)

Ostroumov, P. N., E-mail: ostroumov@anl.gov; Barcikowski, A.; Dickerson, C. A.; Mustapha, B.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2016-02-15

An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne Tandem Linac Accelerator System (ATLAS). The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and significantly improve the purity of reaccelerated radioactive ion beams. The CARIBU EBIS-CB has been successfully commissioned offline with an external singly charged cesium ion source. The performance of the EBIS fully meets the specifications to breed rare isotope beams delivered from CARIBU. The EBIS is being relocated and integrated into ATLAS and CARIBU. A long electrostatic beam transport system including two 180° bends in the vertical plane has been designed. The commissioning of the EBIS and the beam transport system in their permanent location will start at the end of this year.

Off-line commissioning of EBIS and plans for its integration into ATLAS and CARIBU

Science.gov (United States)

Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Mustapha, B.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G.

2016-02-01

An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne Tandem Linac Accelerator System (ATLAS). The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and significantly improve the purity of reaccelerated radioactive ion beams. The CARIBU EBIS-CB has been successfully commissioned offline with an external singly charged cesium ion source. The performance of the EBIS fully meets the specifications to breed rare isotope beams delivered from CARIBU. The EBIS is being relocated and integrated into ATLAS and CARIBU. A long electrostatic beam transport system including two 180° bends in the vertical plane has been designed. The commissioning of the EBIS and the beam transport system in their permanent location will start at the end of this year.
Robotics and remote systems applications

International Nuclear Information System (INIS)

Rabold, D.E.

1996-01-01

This article is a review of numerous remote inspection techniques in use at the Savannah River (and other) facilities. These include: (1) reactor tank inspection robot, (2) californium waste removal robot, (3) fuel rod lubrication robot, (4) cesium source manipulation robot, (5) tank 13 survey and decontamination robots, (6) hot gang valve corridor decontamination and junction box removal robots, (7) lead removal from deionizer vessels robot, (8) HB line cleanup robot, (9) remote operation of a front end loader at WIPP, (10) remote overhead video extendible robot, (11) semi-intelligent mobile observing navigator, (12) remote camera systems in the SRS canyons, (13) cameras and borescope for the DWPF, (14) Hanford waste tank camera system, (15) in-tank precipitation camera system, (16) F-area retention basin pipe crawler, (17) waste tank wall crawler and annulus camera, (18) duct inspection, and (19) deionizer resin sampling
Separation of 248Cm (III) from 252Cf (III) and its use in time resolved fluorescence spectroscopic (TRFS) studies

International Nuclear Information System (INIS)

Murali, M.S.; Nair, A.G.C.; Gujar, R.B.; Jain, A.; Tomar, B.S.; Godbole, S.V.; Reddy, A.V.R.; Manchanda, V.K.

2008-07-01

The present report gives a description of the methodology for the separation of 248 Cm(III) from decayed 252 Cf (III) waste solution. The waste solution was first assayed for 252 Cf content by neutron counting using a neutron well coincidence counter. The sample was subjected to the chemical separation of 248 Cm (III) from 252 Cf (III) following anion and cation exchange chromatography. The alpha spectrum of the separated curium fraction showed peaks due to 246 Cm and 248 Cm while the corresponding alpha spectrum of californium fraction showed 249,250,251,252 Cf. The gamma ray abundances of 249 Cf were determined with respect to its gamma rays of 387 keV and the data agreed well with that in literature. Separated Cm(III) was further characterized by recording its time resolved fluorescence spectrum (TRFS) in aqueous medium. (author)
Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes

International Nuclear Information System (INIS)

Bringer, O.

2007-10-01

This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of 241 Am and 237 Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the 241 Am isomeric branching ratio were precisely measured at thermal energy point. (author)
Testing of ENDF/B cross section data in the Californium-252 neutron benchmark field

International Nuclear Information System (INIS)

Mannhart, W.

1979-01-01

The fission neutron field of 252 Cf presently represents one of the most well-known neutron benchmark fields. For 13 neutron reactions which are of importance in reactor metrology, measurements of spectrum-averaged cross sections, [sigma], performed in this neutron field were compared with calculated average cross sections. This comparison allows one to draw conclusions as to the quality of different sigma(E) data taken from ENDF/B-IV, from ENDF/B-V, and from recent experiments and used in the calculation of average cross sections. The comparison includes an uncertainty analysis regarding the different uncertainty contributions of [sigma], of sigma(E), and of the spectral distribution of 252 Cf fission neutrons. Additionally, in a few examples, sensitivity studies were carried out. The sensitivity of the spectrum-averaged cross sections to individual characteristics of the sigma(E) data, such as normalization factors or shifts in the energy scale, was investigated. Similarly, the sensitivity of [sigma] to the spectral distribution of 252 Cf was determined. 4 figures, 2 tables
Total neutron cross sections of berkelium-249 and californium-249 below 100 eV

International Nuclear Information System (INIS)

Benjamin, R.W.; Harvey, J.A.; Hill, N.W.; Pandey, M.S.; Carlton, R.F.

1979-01-01

The neutron total cross sections of 249 Bk and 249 Cf have been measured from 0.03 to 100 eV using the Oak Ridge Electron Linear Accelerator (ORELA) as a source of pulsed neutrons. The 1.6 mm dia. cylindrical transmission samples contained initially up to 5.3 mg of 98% 249 Bk and 2% 249 Cf: 4.5 years later, when the final measurements were made, the composition of the samples had become 2.5% 249 Bk, 96.9% 249 Cf, and 0.6% 245 Cm. Samples were cooled with liquid nitrogen to reduce Doppler broadening. Thirty-nine resonances were identified in 249 Bk and analyzed using a single-level Breit-Wigner formalism. Fifty-five resonances were identified in 249 Cf and analyzed using an R-matrix multilevel formalism. Fifty-five resonances were identified in 249 Cf and analyzed using an R-matrix multilevel formalism. The resonance parameters obtained have been used to determine the average level spacings and the s-wave neutron and fission strength functions. Where possible, bound-level parameters were derived to fit the thermal neutron total cross section data
HPMA-based drug delivery system and its interactions of human serum albumin: SAXS, ITC, and NMR study

Czech Academy of Sciences Publication Activity Database

Filippov, Sergey K.; Kaberov, Leonid; Zhang, X.; Niebuur, B.-J.; Chytil, Petr; Etrych, Tomáš; Wieland, F.; Velychkivska, Nadiia; Starovoytova, Larisa; Svergun, D.; Papadakis, C.

2017-01-01

Roč. 254, 20 August (2017), s. 455 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] R&D Projects: GA ČR(CZ) GC15-10527J Institutional support: RVO:61389013 Keywords : HPMA * human serum albumin * SAXS Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry
Learning Preference Models for Autonomous Mobile Robots in Complex Domains

Science.gov (United States)

2010-12-01

templates,” in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 167–172, 2009. 128, 153 [254] J. Z. Kolter , P. Abbeel, and A. Y...92] Knepper, R. A. [246] Koller, D. [234] Kolter , J. Z. [254] Konolige, K. [148] Koutsougeras, C. [32] Krotkov, E. [96, 123, 178] Kuffner, J. [252
Novel fluorinated 2-alkyl-2-oxazolines: Three-fold increasing of reactivity in polymerization reaction

Czech Academy of Sciences Publication Activity Database

Kaberov, Leonid; Verbraeken, B.; Riabtseva, Anna; Brus, Jiří; Štěpánek, Petr; Hoogenboom, R.; Filippov, Sergey K.

2017-01-01

Roč. 254, 20 August (2017), s. 304 ISSN 0065-7727. [ACS National Meeting & Exposition /254./. 20.08.2017-24.08.2017, Washington] R&D Projects: GA ČR(CZ) GC15-10527J Institutional support: RVO:61389013 Keywords : poly-2-oxazolines * triblocks * fluorinated Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry
The pin pixel detector--neutron imaging

CERN Document Server

Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Rhodes, N J; Schooneveld, E M; Simmons, J E; Stephenson, R

2002-01-01

The development and testing of a neutron gas pixel detector intended for application in neutron diffraction studies is reported. Using standard electrical connector pins as point anodes, the detector is based on a commercial 100 pin connector block. A prototype detector of aperture 25.4 mmx25.4 mm has been fabricated, giving a pixel size of 2.54 mm which matches well to the spatial resolution typically required in a neutron diffractometer. A 2-Dimensional resistive divide readout system has been adapted to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics. The timing properties of the device match well to the requirements of the ISIS-pulsed neutron source.
7 CFR 1220.254 - Patents, copyrights, inventions, and publications.

Science.gov (United States)

2010-01-01

...) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF..., franchising, or other uses of such patents, copyrights, inventions, or publications, inure to the benefit of...
All projects related to | Page 254 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

2012-02-10

related Violence in Mexico. Project. Violent conflict related to drug trafficking in Mexico has had a profound impact on the quality of life and health of affected communities. Start Date: February 10, 2012. End Date: May 10, 2014. Topic: NARCOTICS ...
24 CFR 92.254 - Qualification as affordable housing: Homeownership.

Science.gov (United States)

2010-04-01

... residents, percentage of owner-occupants) in relation to housing and incomes in the housing market area. An... public facilities and services. If a participating jurisdiction in preparing a neighborhood revitalization strategy under § 91.215(e)(2) of its consolidated plan or Empowerment Zone or Enterprise Community...
40 CFR 25.4 - Information, notification, and consultation responsibilities.

Science.gov (United States)

2010-07-01

... participation in all significant decisions covered by § 25.2(a), particularly where alternative courses of... shall highlight significant issues that will be the subject of decision-making. Whenever possible... distribution of information and must occur sufficiently in advance of decision-making to allow the agency to...
18 CFR 367.2540 - Account 254, Other regulatory liabilities.

Science.gov (United States)

2010-04-01

... accounts, imposed on the service company by the ratemaking actions of regulatory agencies. (See Definitions § 367.1(a)(38).) (b) The amounts included in this account are to be established by those credits which... authorized to charge for its services; or refunds to customers, not provided for in other accounts, will be...
40 CFR 98.254 - Monitoring and QA/QC requirements.

Science.gov (United States)

2010-07-01

...) Standard Test Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter (incorporated... methods. (1) ASTM D4809-06 Standard Test Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb...) Method 18 at 40 CFR part 60, appendix A-6. (2) ASTM D1945-03 Standard Test Method for Analysis of Natural...
Study of the stability of the ground states and K-isomeric states of 250Fm and 254102 against spontaneous fission

International Nuclear Information System (INIS)

Lazarev, Yu.A.; Lobanov, Yu.V.; Sagajdak, R.N.; Utenkov, V.K.; Kharitonov, Yu.P.; Shirokovskij, I.V.; Tret'yakova, S.P.; Oganessyan, Yu.Ts.

1988-01-01

By employing the 249 Cf( 4 He, 3n) and 208 Pb( 48 Ca,2n) reactions, experiments to study the stability against spontaneous fission of the nuclides 250 Fm and 254 102 as well as of the two-quasi-particle (2 q-p) K isomers 250 Fm (T 1/2 =1,8±0,1 s) and 254 102 (T 1/2 =0,28±0,04 s) have been performed. The groundstate spontaneous fission of the two nuclides has been discovered and the corresponding branching ratios b sf and partial half-lives T sf , respectively, have been determined to be: (6,9±1,0)x10 -5 , 0,83±0,15 yr for 250 Fm; (1,7±0,5)x10 -3 , (3,2±0,9)x10 4 s for 254 102. As a by-product of these studies, new data about cross sections of the 206,208 Pb( 48 Ca,xn) reactions have been obtained. Experiments designed to search for the spontaneous fission of the 2 q-p K-isometric states in 250 Fm and 254 102 have not revealed the effect in question. The lower limits of the ratios of the partial spontaneous fission half-lives for the 2 q-p K-isomeric states to those for the respective ground states, T * sf /T sf , have been established to be≥10 -1 for 250m Fm/ 250 Fm and ≥5x10 -3 for 254m 102/ 254 102. This means that the stability of the 2 q-p K-isomeric states in 250 Fm and 254 102 against spontaneous fission is practically not inferior to that of the ground states of these nuclei. In accord with the experimental findings, the theoretical estimates of T * sf /T sf made in the present paper show that, due to the influence of the specialization and blocking effects on the potential energy and the effective mass associated with fission, spontaneous fission from 2 q-p K-isomeric states cannot be facilitated but, on the contrary, should be essentially hindered compared with ground-state spontaneous fission
IDENTITY THEFT SERVICES: Services Offer Some Benefits but Are Limited in Preventing Fraud

Science.gov (United States)

2017-03-01

17-254 Identity Theft Services standards. Those standards require that we plan and perform the audit to obtain sufficient, appropriate evidence to... audited financial statements. Page 34 GAO-17-254 Identity Theft Services Although the websites of many identity theft services ...reasonable assurance that significant decisions on the use of identity theft services are appropriately documented. We provided a draft of this
Transuranium Processing Plant semiannual report of production, status, and plans for period ending June 30, 1975

Energy Technology Data Exchange (ETDEWEB)

King, L.J.; Bigelow, J.E.; Collins, E.D.

1976-03-01

During the period January 1, 1975, through June 30, 1975, the following amounts of transuranium elements were recovered from 22 irradiated HFIR targets: 2g /sup 243/Am, 59 g /sup 244/Cm, 51 mg /sup 249/Bk, 465 mg /sup 252/Cf, 2.5 mg /sup 253/Es, and 1.4 pg /sup 257/Fm. In addition, 45 mg of high-purity /sup 248/Cm was operated from /sup 252/Cf which had been recovered and purified during earlier periods, and 56 mg of a lower-quality /sup 248/Cm was separated from californium purification rework solutions. Five HFIR targets, each containing approximately 9 g of actinides (predominantly curium), were fabricated. A new long-term projection showed that /sup 252/Cf production in the TRU-HFIR complex could increase to as much as 2.5 g/year. During the next 18 months, we expect to recover totals of 46 mg of /sup 249/Bk, 520 mg of /sup 252/Cf, 2.0 mg of /sup 253/Es (in a mixture of isotopes), 220 ..mu..g of high-purity /sup 253/Es, and 1.6 pg of /sup 257/Fm. We also expect to obtain 125 mg of high-purity /sup 248/Cm from purified californium now in storage. There are no plans to process any of the remaining SRP Pu-Al tubes or to irradiate any plutonium targets in the HFIR; thus, we do not expect to recover any /sup 244/Pu. No changes were made in the chemical processing flowsheets normally used at TRU. Two neutron sources were fabricated, bringing the total fabricated to 77. In special projects, we (1) produced about 1 mg of /sup 250/Cf by irradiation of /sup 249/Bk in HFIR rabbits, and (2) processed some irradiated /sup 248/Cm samples and obtained yield and isotopic composition data for use in determining the capture cross section of /sup 249/Cm in the HFIR. The values that are currently being used for transuranium element decay data and for cross-section data in planning irradiation-processing cycles, calculating production forecasts, and assaying products are tabulated in the Appendix.
Microscopic nature of inhomogeneous line broadening: Analysis of the excitation-line-narrowing spectra of Cf4+ in CeF4

International Nuclear Information System (INIS)

Liu, G.K.; Huang, J.; Beitz, J.V.

1993-01-01

Optical transitions between 5f states of tetravalent californium ion doped (1 metal-atom %) into CeF 4 exhibit unusually large inhomogeneous broadening. The nature of the inhomogeneous broadening in this system has been studied by using fluorescence line narrowing and excitation line narrowing (ELN). It is shown that the energy distributions of different electronic states of Cf 4+ in this system are correlated. In the ELN experiments, reduced excitation linewidth was obtained when selectively monitoring fluorescence emission. A linear relation was observed between the excitation energies of crystal-field states of the 5 G 4' manifold and the fluorescence wavelength monitored across the inhomogeneous profile of a 5 G 6' -- 7 F 6' transition. Analysis of these results by means of a microscopic theory proposed by Laird and Skinner [J. Chem. Phys. 90, 3880 (1989)] has provided insights into the structural properties of this disordered system

Chelation and stabilization of berkelium in oxidation state +IV

Science.gov (United States)

Deblonde, Gauthier J.-P.; Sturzbecher-Hoehne, Manuel; Rupert, Peter B.; An, Dahlia D.; Illy, Marie-Claire; Ralston, Corie Y.; Brabec, Jiri; de Jong, Wibe A.; Strong, Roland K.; Abergel, Rebecca J.

2017-09-01

Berkelium (Bk) has been predicted to be the only transplutonium element able to exhibit both +III and +IV oxidation states in solution, but evidence of a stable oxidized Bk chelate has so far remained elusive. Here we describe the stabilization of the heaviest 4+ ion of the periodic table, under mild aqueous conditions, using a siderophore derivative. The resulting Bk(IV) complex exhibits luminescence via sensitization through an intramolecular antenna effect. This neutral Bk(IV) coordination compound is not sequestered by the protein siderocalin—a mammalian metal transporter—in contrast to the negatively charged species obtained with neighbouring trivalent actinides americium, curium and californium (Cf). The corresponding Cf(III)-ligand-protein ternary adduct was characterized by X-ray diffraction analysis. Combined with theoretical predictions, these data add significant insight to the field of transplutonium chemistry, and may lead to innovative Bk separation and purification processes.
Operation manual for the INEL on-line mass-separator facility

International Nuclear Information System (INIS)

Anderl, R.A.

1984-06-01

This report is an operation manual for an on-line mass-separator facility which is located in Building 661 at the Test Reactor Area of the Idaho National Engineering Laboratory. The facility provides mass-separated sources of short-lived fission-product radionuclides whose decay properties can be studied using a variety of nuclear spectroscopic techniques. This facility is unique in that it utilizes the gas-jet technique to transport fission products from a 252 Cf source located in a hot cell to the ion source of the mass separator. This document includes the following: (a) a detailed description of the facility, (b) identification of equipment hazards and safety controls, (c) detailed operating procedures for startup, continuous operation and shutdown, (d) operating procedures for the californium hot cell, and (e) an operator's manual for the automated moving tape collector/data acquisition system. 7 references, 16 figures, 8 tables
Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes; Mesures des sections efficaces de capture et potentiels d'incineration des actinides mineurs dans les hauts flux de neutrons: Impact sur la transmutation des dechets

Energy Technology Data Exchange (ETDEWEB)

Bringer, O

2007-10-15

This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of {sup 241}Am and {sup 237}Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the {sup 241}Am isomeric branching ratio were precisely measured at thermal energy point. (author)
Operational safety at the radiometallurgy laboratory of Fontenay-aux-Roses

International Nuclear Information System (INIS)

Hayet, Lucien; Petit, Pierre; Conche, Roger.

1976-01-01

Opened in 1967, the Radiometallurgy Laboratory is responsible for the examination of plutonium 239 based nuclear fuels of breeder reactors such as Rapsodie and Phenix. Part of the same laboratory is also responsible for the manufacture of californium 252 sources. These neutron sources can have a neutron fluency yield of 2,3 10 10 n/s/4π (i.e. 10mg of 252cf). This large laboratory includes a total area of 117m 2 of hot surfaces. It also includes 14 high activity cells with a capacity of 100000Ci at 1MeV. Located only 7km from the center of Paris, it must incorporate a special design and a particularly sure safety policy. Several statistics are given: irradiations, contaminations, incidents, quantity of fissile material, solid and liquid wastes etc... The principles of safety management are outlined and an analysis given of this basic nuclear facility [fr
Lethal action of ultraviolet and visible (blue violet) radiations at defined wavelengths on human lymphoblastoid cells; action spectra and interaction sites

Energy Technology Data Exchange (ETDEWEB)

Tyrrell, R.M.; Werfelli, P.; Moraes, E.C. (Institut Suisse de Recherches Experimentales sur le Cancer, Lausanne)

1984-02-01

The repair proficient human lymphoblastoid line (TK6) has been employed to construct an action spectrum for the lethal action of ultraviolet (UV) radiation in the range 254 to 434 nm and to examine possible interactions between longer (334, 365 and 405 nm) and shorter wavelength (254 and 313 nm) radiations. The action spectrum follows a DNA absorption spectrum fairly closely out to 360 nm. As in previously determined lethal action spectra for procaryotic and eucaryotic cell populations, there is a broad shoulder in the 334 to 405 nm region which could reflect the existence of either (a) a non-DNA chromophore or (b) a unique photochemical reaction in the DNA over this region. Pre-treatment with radiation at 334 or 365 nm causes either a slight sensitivity to (low fluences) or protection from (higher fluences) subsequent exposure to radiation at a shorter wavelength (254 or 313 nm). Pre-irradiation at a visible wavelength (405 nm) at all fluence levels employed sensitizes the populations to treatment with 254 or 313 nm radiations. These interactions will influence the lethal outcome of cellular exposure to broad-band radiation sources.
Thin layer chromatographic analyses of pesticides in a soil ecosystem

International Nuclear Information System (INIS)

Afful, S.; Dogbe, S.A.; Ahmad, K.; Ewusie, A.T.

2008-01-01

Silica gel 60, silica gel 60 F 254 , and aluminium oxide as adsorbents were used to investigate their suitability for the analysis and detection of the pesticides: nitrofen, atrazine, diuron, dioxacarb, propoxur, propanil, carbaryl and cypermethrin in soil ecosystem using ethyl acetate, chloroform, dichloromethane and ethyl acetate/chloroform (1:1) as developing solvents. O-tolidine and potassium iodide reagent were used for the detection of pesticides. R f values obtained for the pesticides using the silica gel 60-ethyl acetate. silica gel 60F 254 -ethyl acetate, silica gel 60 chloroform, silica gel 60 F 254 - chloroform, silica gel 60 - (1:1) ethyl acetate/chloroform and silica gel 60 F 254 - (1:1) ethyl acetate/chloroform systems generally were within the stipulated range of 0.4-0.8. R f values obtained for the pesticides using silica gel 60-dichloromethane systems were very low except for cypermethrin and nitrofen. Analysis with aluminium oxide coated plates gave a heavy yellow background with the detection reagent making visualization of spots difficult. Aluminium oxide coated plate is, therefore, not recommended when o-tolidine plus potassium iodide is used as detection reagent. (au)
Lethal action of ultraviolet and visible (blue violet) radiations at defined wavelengths on human lymphoblastoid cells; action spectra and interaction sites

International Nuclear Information System (INIS)

Tyrrell, R.M.; Werfelli, P.; Moraes, E.C.

1984-01-01

The repair proficient human lymphoblastoid line (TK6) has been employed to construct an action spectrum for the lethal action of ultraviolet (UV) radiation in the range 254 to 434 nm and to examine possible interactions between longer (334, 365 and 405 nm) and shorter wavelength (254 and 313 nm) radiations. The action spectrum follows a DNA absorption spectrum fairly closely out to 360 nm. As in previously determined lethal action spectra for procaryotic and eucaryotic cell populations, there is a broad shoulder in the 334 to 405 nm region which could reflect the existence of either (a) a non-DNA chromophore or (b) a unique photochemical reaction in the DNA over this region. Pre-treatment with radiation at 334 or 365 nm causes either a slight sensitivity to (low fluences) or protection from (higher fluences) subsequent exposure to radiation at a shorter wavelength (254 or 313 nm). Pre-irradiation at a visible wavelength (405 nm) at all fluence levels employed sensitizes the populations to treatment with 254 or 313 nm radiations. These interactions will influence the lethal outcome of cellular exposure to broad-band radiation sources. (author)
The biogeochemical fingerprint of urbanization: increasing carbon quality in Maine headwater streams

Science.gov (United States)

Parr, T.; Cronan, C.; Ohno, T.; Simon, K. S.

2012-12-01

Conversion of land cover to urban use is an accelerating global phenomenon. Physical landscape change manifests as the replacement of forests, grasslands, and wetlands with buildings, novel vegetation, and infrastructure. This physical change also brings with it a change in the human management of the landscape for aesthetic and practical purposes (i.e. road salt applications). Although urbanization's effects on inorganic nutrients have been well studied, far less is known about the interactive influences of urbanization and urban landscape management practices on dissolved organic matter (DOM), a key energy source essential to ecosystem function. We examined the seasonal abundance and composition of DOM, nutrients, and common cations in 116 small streams along a gradient of urbanization (0-60% total watershed imperviousness, TWI), in Maine, USA. Dissolved organic carbon concentration ranged from 0.5 to 20 ppm with no clear relationship to watershed urbanization. In contrast, DOM composition, quantified with specific ultra violet absorbance at 254 nm (SUVA_{254}), fluorescence indices, and parallel factor analysis (PARAFAC), changed considerably with increasing urbanization. SUVA_{254} indicated a shift from higher molecular weight humic compounds (SUVA_{254}>4) toward lower molecular weight compounds (SUVA_{254}road salt application may mobilize base cations into streams draining urbanized watersheds. There was a strong negative relationship between humic-like DOM components and Ca^{2+} (R^2=0.3-0.5, psalts over a natural range (0 - 6 mM) showed that ^{2+} cations (esp. Ca^{2+}) preferentially flocculated the humic fraction of DOM (R^2=0.6-0.9, premoving terrestrial C from the aquatic DOM pool in urban landscapes.
The Effect of Conformational Variability of Phosphotriesterase upon N-acyl-L-homoserine Lactone and Paraoxon Binding: Insights from Molecular Dynamics Studies

Directory of Open Access Journals (Sweden)

Dongling Zhan

2013-12-01

Full Text Available The organophosphorous hydrolase (PTE from Brevundimonas diminuta is capable of degrading extremely toxic organophosphorous compounds with a high catalytic turnover and broad substrate specificity. Although the natural substrate for PTE is unknown, its loop remodeling (loop 7-2/H254R led to the emergence of a homoserine lactonase (HSL activity that is undetectable in PTE (kcat/km values of up to 2 × 104, with only a minor decrease in PTE paraoxonase activity. In this study, homology modeling and molecular dynamics simulations have been undertaken seeking to explain the reason for the substrate specificity for the wild-type and the loop 7-2/H254R variant. The cavity volume estimated results showed that the active pocket of the variant was almost two fold larger than that of the wild-type (WT enzyme. pKa calculations for the enzyme (the WT and the variant showed a significant pKa shift from WT standard values (ΔpKa = 3.5 units for the His254residue (in the Arg254 variant. Molecular dynamics simulations indicated that the displacement of loops 6 and 7 over the active site in loop 7-2/H254R variant is useful for N-acyl-L-homoserine lactone (C4-HSL with a large aliphatic chain to site in the channels easily. Thence the expanding of the active pocket is beneficial to C4-HSL binding and has a little effect on paraoxon binding. Our results provide a new theoretical contribution of loop remodeling to the rapid divergence of new enzyme functions.
A comparative study on the efficiency of ozonation and coagulation-flocculation as pretreatment to activated carbon adsorption of biologically stabilized landfill leachate.

Science.gov (United States)

Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim T M; Demeestere, Kristof; Van Hulle, Stijn W H

2015-09-01

The present work investigates the potential of coagulation-flocculation and ozonation to pretreat biologically stabilized landfill leachate before granular activated carbon (GAC) adsorption. Both iron (III) chloride (FeCl3) and polyaluminium chloride (PACl) are investigated as coagulants. Better organic matter removal is observed when leachate was treated with FeCl3. At a dose of 1mg FeCl3/mg CODo (CODo: initial COD content), the COD and α254 removal was 66% and 88%, respectively. Dosing 1mg PACl/mg CODo resulted in 44% COD and 72% α254 removal. The settle-ability of sludge generated by PACl leveled off at 252mL/g, while a better settle-ability of 154mL/g was obtained for FeCl3 after dosing 1mg coagulant/mg CODo. For ozonation, the percentage of COD and α254 removal increased as the initial COD concentration decreased. Respectively 44% COD and 77% α254 removal was observed at 112mg COD/L compared to 5% COD and 26% α254 removal at 1846mg COD/L. Subsequent activated carbon adsorption of ozonated, coagulated and untreated leachate resulted in 77%, 53% and 8% total COD removal after treatment of 6 bed volumes. Clearly showing the benefit of treating the leachate before GAC adsorption. Mathematical modeling of the experimental GAC adsorption data with Thomas and Yoon-Nelson models show that ozonation increases the adsorption capacity and breakthrough time of GAC by a factor of 2.5 compared to coagulation-flocculation. Copyright © 2015 Elsevier Ltd. All rights reserved.
Integration of biofiltration and advanced oxidation processes for tertiary treatment of an oil refinery wastewater aiming at water reuse.

Science.gov (United States)

Nogueira, A A; Bassin, J P; Cerqueira, A C; Dezotti, M

2016-05-01

The combination of biological and chemical oxidation processes is an interesting approach to remove ready, poor, and non-biodegradable compounds from complex industrial wastewaters. In this study, biofiltration followed by H2O2/UV oxidation (or microfiltration) and final reverse osmosis (RO) step was employed for tertiary treatment of an oil refinery wastewater. Biofiltration alone allowed obtaining total organic carbon (TOC), chemical oxygen demand (COD), UV absorbance at 254 nm (UV254), ammonium, and turbidity removal of around 46, 46, 23, 50, and 61 %, respectively. After the combined biological-chemical oxidation treatment, TOC and UV254 removal amounted to 88 and 79 %, respectively. Whereas, the treatment performance achieved with different UV lamp powers (55 and 95 W) and therefore distinct irradiance levels (26.8 and 46.3 mW/cm(2), respectively) were very similar and TOC and UV254 removal rates were highly affected by the applied C/H2O2 ratio. Silt density index (SDI) was effectively reduced by H2O2/UV oxidation, favoring further RO application. C/H2O2 ratio of 1:4, 55 W UV lamp, and 20-min oxidation reaction corresponded to the experimental condition which provided the best cost/benefit ratio for TOC, UV254, and SDI reduction from the biofilter effluent. The array of treatment processes proposed in this study has shown to be adequate for tertiary treatment of the oil refinery wastewater, ensuring the mitigation of membrane fouling problems and producing a final effluent which is suitable for reuse applications.
Regional variation in wood modulus of elasticity (stiffness) and modulus of rupture (strength) of planted loblolly pine in the United States

Science.gov (United States)

Antony Finto; Lewis Jordan; Laurence R. Schimleck; Alexander Clark; Ray A. Souter; Richard F. Daniels

2011-01-01

Modulus of elasticity (MOE), modulus of rupture (MOR), and specific gravity (SG) are important properties for determining the end-use and value of a piece of lumber. This study addressed the variation in MOE, MOR, and SG with physiographic region, tree height, and wood type. Properties were measured from two static bending samples (dimensions 25.4 mm Ã 25.4 mm Ã 406.4...
Maximum permissible concentration (MPC) values for spontaneously fissioning radionuclides

International Nuclear Information System (INIS)

Ford, M.R.; Snyder, W.S.; Dillman, L.T.; Watson, S.B.

1976-01-01

The radiation hazards involved in handling certain of the transuranic nuclides that exhibit spontaneous fission as a mode of decay were reaccessed using recent advances in dosimetry and metabolic modeling. Maximum permissible concentration (MPC) values in air and water for occupational exposure (168 hr/week) were calculated for 244 Pu, 246 Cm, 248 Cm, 250 Cf, 252 Cf, 254 Cf, /sup 254m/Es, 255 Es, 254 Fm, and 256 Fm. The half-lives, branching ratios, and principal modes of decay of the parent-daughter members down to a member that makes a negligible contribution to the dose are given, and all daughters that make a significant contribution to the dose to body organs following inhalation or ingestion are included in the calculations. Dose commitments for body organs are also given
Multiplicity and correlated energy of gamma rays emitted in the spontaneous fission of Californium-252

International Nuclear Information System (INIS)

Brunson, G.S. Jr.

1982-06-01

An array of eight high-speed plastic scintillation detectors has been used to infer a mathematical model for the emission multipliciy of prompt gammas in the spontaneous fission of 252 Cf. Exceptional time resolution and coincidence capability permitted the separation of gammas from fast neutrons over a flight path of approximately 10 cm. About 20 different distribution models were tested. The average energy of the prompt gammas is inversely related to the number emitted; however, this inverse relationship is not strong and the total gamma energy does increase with increasing gamma number. An extension of the experiment incorporated a lithium-drifted germanium gamma spectrometer that resolved nearly 100 discrete gammas associated with fission. Of these gammas, some were preferentially associated with fission in which few gammas were emitted. Certain others were more frequent when many gammas were emitted. Results are presented
Remarkably High Stability of Late Actinide Dioxide Cations: Extending Chemistry to Pentavalent Berkelium and Californium.

Science.gov (United States)

Dau, Phuong D; Vasiliu, Monica; Peterson, Kirk A; Dixon, David A; Gibson, John K

2017-12-06

Actinyl chemistry is extended beyond Cm to BkO 2 + and CfO 2 + through transfer of an O atom from NO 2 to BkO + or CfO + , establishing a surprisingly high lower limit of 73 kcal mol -1 for the dissociation energies, D[O-(BkO + )] and D[O-(CfO + )]. CCSD(T) computations are in accord with the observed reactions, and characterize the newly observed dioxide ions as linear pentavalent actinyls; these being the first Bk and Cf species with oxidation states above IV. Computations of actinide dioxide cations AnO 2 + for An=Pa to Lr reveal an unexpected minimum for D[O-(CmO + )]. For CmO 2 + , and AnO 2 + beyond EsO 2 + , the most stable structure has side-on bonded η 2 -(O 2 ), as An III peroxides for An=Cm and Lr, and as An II superoxides for An=Fm, Md, and No. It is predicted that the most stable structure of EsO 2 + is linear [O=Es V =O] + , einsteinyl, and that FmO 2 + and MdO 2 + , like CmO 2 + , also have actinyl(V) structures as local energy minima. The results expand actinide oxidation state chemistry, the realm of the distinctive actinyl moiety, and the non-periodic character towards the end of the periodic table. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Neutron Protection Factor Determination and Validation for a Vehicle Surrogate Using a Californium Fission Source

Science.gov (United States)

2017-06-01

study the laws governing shock wave propagation, and evaluate the suitability of military operations after being subjected to their use. During...14]. MCNP6.1 then outputs a dose spectrum, instead of the standard fluence spectrum created from the “ f4 ” tally [14]. In order to produce the dose...manually, an unmodified fluence tally ( f4 ) was exported externally to a spreadsheet. The energy bins were summed and grouped to mimic the energy bin
Crevice Corrosion Behavior of 45 Molybdenum-Containing Stainless Steels in Seawater.

Science.gov (United States)

1981-12-01

Armco, Avesta Jernverks, Cabot, Carpenter Technology, Crucible, Eastern, Firth-Brown, Huntington, Jessup, Langley Alloys, and Uddeholm. 16...Department of Energy, Report ANL/OTEC-BCM-022. 7. Wallen, B., and M. Liljas, " Avesta 254 SMO - A New, High Molybdenum Stainless Steel," presented at NKM8...1977).; 11. Wallen, B., " Avesta 254 SMO - A Stainless Steel for Seawater Service," presented at the Advanced Stainless Steels for Turbine Condensors
Degradation kinetics and mechanism of β-lactam antibiotics by the activation of H{sub 2}O{sub 2} and Na{sub 2}S{sub 2}O{sub 8} under UV-254 nm irradiation

Energy Technology Data Exchange (ETDEWEB)

He, Xuexiang [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); Department of Civil and Environmental Engineering and Nireas-International Water Research Centre, School of Engineering, University of Cyprus, PO Box 20537, 1678 Nicosia (Cyprus); Mezyk, Stephen P. [Department of Chemistry and Biochemistry, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, CA 90840 (United States); Michael, Irene; Fatta-Kassinos, Despo [Department of Civil and Environmental Engineering and Nireas-International Water Research Centre, School of Engineering, University of Cyprus, PO Box 20537, 1678 Nicosia (Cyprus); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States); Department of Civil and Environmental Engineering and Nireas-International Water Research Centre, School of Engineering, University of Cyprus, PO Box 20537, 1678 Nicosia (Cyprus)

2014-08-30

Graphical abstract: - Highlights: • Removal efficiency was comparable at different UV fluence rates but same fluence. • Reducing pH to 3 or 2 did not inhibit the removal of nitrobenzene by UV/S{sub 2}O{sub 8}{sup 2−}. • 1.84 × 10{sup −14} M [HO{sup •} ]{sub ss} and 3.10 × 10{sup −13} M [SO{sub 4}{sup •} {sup −}]{sub ss} in UV/S{sub 2}O{sub 8}{sup 2−} were estimated. • HO{sup •} reacted faster with the β-lactams than SO{sub 4}{sup •} {sup −} but sharing similar byproducts. • Transformation pathways included hydroxylation, hydrolysis and decarboxylation. - Abstract: The extensive production and usage of antibiotics have led to an increasing occurrence of antibiotic residuals in various aquatic compartments, presenting a significant threat to both ecosystem and human health. This study investigated the degradation of selected β-lactam antibiotics (penicillins: ampicillin, penicillin V, and piperacillin; cephalosporin: cephalothin) by UV-254 nm activated H{sub 2}O{sub 2} and S{sub 2}O{sub 8}{sup 2−} photochemical processes. The UV irradiation alone resulted in various degrees of direct photolysis of the antibiotics; while the addition of the oxidants improved significantly the removal efficiency. The steady-state radical concentrations were estimated, revealing a non-negligible contribution of hydroxyl radicals in the UV/S{sub 2}O{sub 8}{sup 2−} system. Mineralization of the β-lactams could be achieved at high UV fluence, with a slow formation of SO{sub 4}{sup 2−} and a much lower elimination of total organic carbon (TOC). The transformation mechanisms were also investigated showing the main reaction pathways of hydroxylation (+16 Da) at the aromatic ring and/or the sulfur atom, hydrolysis (+18 Da) at the β-lactam ring and decarboxylation (–44 Da) for the three penicillins. Oxidation of amine group was also observed for ampicillin. This study suggests that UV/H{sub 2}O{sub 2} and UV/S{sub 2}O{sub 8}{sup 2−} advanced
MOLECULAR DETECTION AND CLONING FOR RICKETTSIA-LIKE BACTERIA OF MILKY HAEMOLYMPH DISEASE OF SPINY LOBSTER Panulirus spp.

Directory of Open Access Journals (Sweden)

Isti Koesharyani

2017-01-01

Full Text Available Spiny lobster (Panulirus homarus and Panulirus ornatus are important commodities for Indonesia. The aquaculture of lobster is susceptible for several diseases like parasite, fungi, bacteria, and virus. Among those diseases, milky haemolymph disease (MHD is often seen as a symptom to mass mortality occurred at lobster farms in Gerupuk Bay of Lombok. The purpose of this study was to determine the lobster diseases on cage culture in Gerupuk Bay of Lombok, West Nusa Tenggara. The study was undertaken from January to March 2015. Diseases status was determined by application of molecular plat-form, polymerase chain reaction (PCR with designation of specific primer for MHD (254F/R, 254F: 5’-CGA-GGA-CCA-GAG-ATG-GAC-CTT-3’ and 254R: 5’-GCT-CAT-TGT-CAC-CGC-CAT-TGT-3’ with PCR size product of 254 bp. and for cloned the pathogen was used TA-cloning Invitrogen for the DNA plasmid as positive control for other analysis. Several tissue samples i.e hepatopancreas, haemolymph, part of muscle hepatopancreas P. homarus and P. ornatus were taken from cage culture farms at Gerupuk Bay then preserved on 90% ethanol for further analysis by PCR and then the amplificated DNA were cloned into pCR®2.1 plasmid and transformed into competent E. coli. The result showed that almost all lobster samples from Gerupuk Bay were positive infected by MHD, as the results of PCR amplification whereas the band appeared at 254bp. Also MHD plasmid has been successfully cloned and will be used for further examination. Histopathologically in hepatopancreas infection have seen necrosis that contain numerous of rickettsia-like bacteria.
Photodegradation of the azole fungicide climbazole by ultraviolet irradiation under different conditions: Kinetics, mechanism and toxicity evaluation

Energy Technology Data Exchange (ETDEWEB)

Liu, Wang-Rong; Ying, Guang-Guo, E-mail: guang-guo.ying@gig.ac.cn; Zhao, Jian-Liang; Liu, You-Sheng; Hu, Li-Xin; Yao, Li; Liang, Yan-Qiu; Tian, Fei

2016-11-15

Highlights: • Climbazole (CZ) could be effectively degraded under UV-254 irradiation. • CZ underwent direct and self-sensitized photolysis involving ROS. • The main photodegradation by-products of CZ were identified and semi-quantitated. • Pathway includes hydroxylative dechlorination, dechlorination, and de-pinacolone. • The toxicity of the photodegradation system reduced after UV-254 irradiation. - Abstract: Climbazole (CZ) has been known to persist in various environmental media, and may cause potential risks to aquatic organisms. This study investigated the photodegradation of CZ by ultraviolet (UV, 254 nm) under different conditions. The results revealed that CZ could be effectively degraded in aqueous solutions under UV-254 irradiation with a half-life of 9.78 min (pH = 7.5), and the photodegradation followed pseudo-first-order kinetics. pH had almost no effect on its rate constants and quantum yields; but the water quality of natural waters could affect the photolysis of CZ, and the coexisting constituents such as Fe{sup 3+}, NO{sub 3}{sup −}, and HA obviously inhibited its photolysis. The addition of different radical scavengers also inhibited the photodegradation of CZ due to the reduction of reactive oxygen species (ROS). CZ underwent direct and self-sensitized photolysis involving ROS. Based on the identified photodegradation by-products, the proposed pathways included hydroxylative dechlorination, dechlorination and de-pinacolone. Moreover, toxicity evaluation using duckweed found significant toxicity reduction in the photodegradation system of CZ after the irradiation of UV-254, and the remaining by-products did not pose extra toxicity compared with CZ itself. These findings from present study suggest that CZ in effluent could be further reduced by applying UV photolysis treatment.

Comparison of the Performance of Poly Aluminum Chloride (PACl, Ferric Chloride (FeCl3, in Turbidity and Organic Matter Removal; from Water Source, Case-Study: Karaj River, in Tehran Water Treatment Plant No. 2

Directory of Open Access Journals (Sweden)

Mohammad Abdolah zadeh

2009-06-01

Full Text Available Coagulation and flocculation are the principal units in water treatment processes. In this study, the Jar test was used to investigate the effects of the pH and TOC on FeCl3 and PACl coagulants for further removal of turbidity, organic matter, aluminum, total organic carbon (TOC, dissolved organic carbon (DOC, organic Aadsorption at a wavelength of 254 nm (UV254 nm , alkalinity, residual aluminum and ferric, total trihalomethans (TTHMs in the Karaj River in the year 2007- 2008. These experiments were conducted through a bench scale study using conventional coagulation in the influent to Tehran Water Treatment Plant No. 2 (TWTP2.With normal pH levels, PACl demonstrated more efficiency than FeCl3 in removing turbidity, TOC, UV254 nm, and TTHMs. The lower coagulant consumption, high floc size, lower floc detention time, lower sludge production, lack of the need for pH adjustment in turbidity of 25 NTU and the lower alum consumption were the advantages of PACl application instead of FeCl3 as a coagulant. Also, PACl application was efficient at low turbidity (2 NTU, average turbidity (6 NTU, and high turbidity (100 NTU in TOC, turbidity, UV254 nm , and DOC removal. Thus, PACl is an economical alternative as a coagulant in TWTP2.
Iranian Influence in Iraqi Shi’a Groups

Science.gov (United States)

2012-06-01

Movement in Iraq, 254. 60 Jabar, The Shīʻite Movement in Iraq, 254. 61 Robert Fisk, The Great War For Civilisation : the Conquest of the Middle East...by Iran in 62 Fisk, The Great War For Civilisation : the Conquest of the Middle East, 647. 63 John...U.S. soldier missing in Iraq. AAH sources indicated that the group was not behind the killing but rather just mediators in the process of returning
The significance of chromosome deletions in atomic-bomb survivors

International Nuclear Information System (INIS)

Tanaka, Kimio; Shigeta, Chiharu; Oguma, Nobuo; Kamada, Nanao; Deng, Z.; Niimi, Masanobu; Aisaka, Tadaichi.

1986-01-01

In 39 A-bomb survivors 40 years after exposure at ≤ 1,000 m from ground zero, the frequency and features of chromosome deletions in peripheral lymphocytes were examined using a differential staining technique. Simultaneously, in vitro irradiation experiment with Cf-252 was made to infer chromosome aberrations occuring immediately after exposure. Californium-252 with 100 rad induced dicentric and ring chromosomes in 40 % of the cells and acentric fragments in 44 %. Among the A-bomb survivors, chromosome aberrations were observed in 651 (21 %) of the total 3,136 cells. There were 146 cells with deletions (22 % of abnormal cells; 5 % of the total cells), and 10 cells with acentric fragment (0.3 % of the total cells). The figure for deletions was far higher than that reported in the literature. A large number of deletions were seen in chromosomes no.4, no.21, and no.22, and a few deletions in chromosomes no.7 and no.20. Significance of chromosome deletions is discussed. (Namekawa, K.)
Cleanex process: a versatile solvent extraction process for recovery and purification of lanthanides, americium, and curium

International Nuclear Information System (INIS)

Bigelow, J.E.; Collins, E.D.; King, L.J.

1979-01-01

At a concentration of 1 M in straight-chain hydrocarbon diluent, HDEHP will extract americium, curium, and other trivalent actinide and lanthanide elements from dilute acid or salt solutions. The solute is back-extracted with more concentrated acid, either nitric or hydrochloric. The process has been used in the continuous, countercurrent mode, but its greatest advantage arises in batch extractions where the excess acid can be titrated with NaOH to produce a final acidity of about 0.03 M. Under these conditions, 99% recovery can be achieved, usually in one stage. Cleanex was used on the 50-liter scale at the Transuranium Processing Plant at Oak Ridge for 12 years to provide a broad spectrum cleanup to transuranium elements before applying more sophisticated techniques for separating individual products. The process is also used routinely to recover excessive losses of curium and/or californium from plant waste streams. The solvent system is relatively resistant to radiation damage, being usable up to 200 W-h/liter
Dynamic vortex dust structures in a nuclear-track plasma

International Nuclear Information System (INIS)

Rykov, V A; Khudyakov, A V; Filinov, V S; Vladimirov, V I; Deputatova, L V; Krutov, D V; Fortov, V E

2003-01-01

Results are presented from Monte Carlo calculations of the electric charge on dust grains in a plasma produced during the slowing down of radioactive decay products of californium nuclei in neon. The dust grain charging is explained as being due to the drift of electrons and ions in an external electric field. It is shown that the charges of the grains depend on their coordinates and strongly fluctuate with time. The time-averaged grain charges agree with the experimental data obtained on ordered liquid-like dust structures in a nuclear-track plasma. The time-averaged dust grain charges are used to carry out computer modelling of the formation of dynamic vortex structures observed in experiments. Evidence is obtained for the fact that the electrostatic forces experienced by the dust grains are potential in character. The paper is supplemented by a video clip showing the typical dynamics of the simulated vortex dust structure
Monitoring taconite process streams with thermal neutron capture-gamma ray analysis. Report of investigations/1980

International Nuclear Information System (INIS)

Woodbury, F.B.W.

1980-12-01

The Bureau of Mines is evaluating alternative technologies to treat oxidized taconites. Since process control is an essential element in the application of these process technologies, research was performed on a prototype monitoring system utilizing a californium-252 (252-Cf) neutron source and a thermal neutron capture-gamma ray spectra analysis method to measure the amount of iron and percent solids in process slurries. The prototype system was used to monitor the concentrate and tailing streams in a 900-lb/hr flotation pilot plant during continuous around-the-clock tests. The iron content of the process slurries was determined by measuring the total peak areas under the capture spectrum peaks at 7.626-7.632 MeV, the associated escape peaks at 7.136-7.122 and 6.626-6.612 MeV, and the iron doublets at 4.900 and 4.998 MeV. A potential method for determining the percent solids in process slurries using the 2.22 MeV hydrogen capture peak is discussed
A survey of uses and users of 252Cf

International Nuclear Information System (INIS)

Bigelow, J.E.; Alexander, C.W.; King, L.J.; Knauer, J.B.; Notz, K.J.

1989-01-01

Californium-252, which is one of the transuranium-element isotopes being produced in the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL), has found many applications in service to industry and medicine. As a neutron source, 252 Cf is unique in providing a highly concentrated and extremely reliable neutron spectrum from a very small assembly. Over the past 22 years, 252 Cf has been applied with great success to cancer therapy, to neutron radiography of objects ranging from flowers to entire aircraft, to startup sources for nuclear reactors, to fission activation assay for quality control and safeguards of all commercial nuclear fuel, and to many other beneficial uses, some of which are now poised for further growth. The extensive exploitation of this highly specialized product has been made possible through 252 Sales/Loan programs sponsored by the US DOE Office of Nuclear Materials Production, initially at the Savannah River Laboratory and now at ORNL
Actinide metals

Energy Technology Data Exchange (ETDEWEB)

Brown, Paul L. [Geochem Australia, Kiama, NSW (Australia); Ekberg, Christian [Chalmers Univ. of Technology, Goeteborg (Sweden). Nuclear Chemistry/Industrial Materials Recycling

2016-07-01

All isotopes of actinium are radioactive and exist in aqueous solution only in the trivalent state. There have been very few studies on the hydrolytic reactions of actinium(III). The hydrolysis reactions for uranium would only be important in alkaline pH conditions. Thermodynamic parameters for the hydrolysis species of uranium(VI) and its oxide and hydroxide phases can be determined from the stability and solubility constants. The hydrolytic behaviour of neptunium(VI) is quite similar to that of uranium(VI). The solubility constant of NpO{sub 2}OH(am) has been reported a number of times for both zero ionic strength and in fixed ionic strength media. Americium can form four oxidation states in aqueous solution, namely trivalent, tetravalent, pentavalent and hexavalent. Desire, Hussonnois and Guillaumont determined stability constants for the species AmOH{sup 2+} for the actinides, plutonium(III), americium(III), curium(III), berkelium(III) and californium(III) using a solvent extraction technique.
Actinide metals

International Nuclear Information System (INIS)

Brown, Paul L.; Ekberg, Christian

2016-01-01

All isotopes of actinium are radioactive and exist in aqueous solution only in the trivalent state. There have been very few studies on the hydrolytic reactions of actinium(III). The hydrolysis reactions for uranium would only be important in alkaline pH conditions. Thermodynamic parameters for the hydrolysis species of uranium(VI) and its oxide and hydroxide phases can be determined from the stability and solubility constants. The hydrolytic behaviour of neptunium(VI) is quite similar to that of uranium(VI). The solubility constant of NpO 2 OH(am) has been reported a number of times for both zero ionic strength and in fixed ionic strength media. Americium can form four oxidation states in aqueous solution, namely trivalent, tetravalent, pentavalent and hexavalent. Desire, Hussonnois and Guillaumont determined stability constants for the species AmOH 2+ for the actinides, plutonium(III), americium(III), curium(III), berkelium(III) and californium(III) using a solvent extraction technique.
Nuclear Chemistry Institute, Mainz University. Annual Report 1995

International Nuclear Information System (INIS)

Denschlag, H.O.

1996-03-01

The annual report of the Institut fuer Kernchemie addresses inter alia three main research activities. The first belongs to the area of basic research, covering studies in the fields of nuclear fission, chemistry of the super-heavy elements and of heavy-ion reactions extending from the Coulomb barrier to relativistic energies, and nuclear astrophysics in connection with the ''r process''. By means of laser technology, high-precision data could be measured of the ionization energies of berkelium and californium. Studies of atomic clusters in the vacuum of an ionization trap revealed interesting aspects. The second major activity was devoted to the analysis of environmental media, applying inter alia neutron activation analysis and resonance ionization mass spectroscopy (RIMS). The third activity resulted in the development of novel processes, or the enhancement of existing processes or methods, for applications in basic research work and in environmental analytics. Another item of interest is the summarizing report on the operation of the TRIGA research reactor. (orig./SR) [de
Test and evaluation results of the 252Cf shuffler at the Savannah River Plant

International Nuclear Information System (INIS)

Crane, T.W.

1981-03-01

The 252 Cf Shuffler, a nondestructive assay instrument employing californium neutron source irradiation and delayed-neutron counting, was developed for measuring 235 U content of scrap and waste items generated at the Savannah River Plant (SRP) reactor fuel fabrication facility. The scrap and waste items include high-purity uranium-aluminum alloy ingots as well as pieces of castings, saw and lathe chips from machining operations, low-purity items such as oxides of uranium or uranium intermixed with flux materials found in recovery operations, and materials not recoverable at SRP such as floor sweepings or residues from the uranium scrap recovery operation. The uranium contains about 60% 235 U with the remaining isotopes being 236 U, 238 U, and 234 U in descending order. The test and evaluation at SRP concluded that the accuracy, safety, reliability, and ease of use made the 252 Cf Shuffler a suitable instrument for routine use in an industrial, production-oriented plant
General purpose nuclear irradiation chamber

International Nuclear Information System (INIS)

Nurul Fadzlin Hasbullah; Nuurul Iffah Che Omar; Nahrul Khair Alang Md Rashid; Jaafar Abdullah

2013-01-01

Nuclear technology has found a great need for use in medicine, industry, and research. Smoke detectors in our homes, medical treatments and new varieties of plants by irradiating its seeds are just a few examples of the benefits of nuclear technology. Portable neutron source such as Californium-252, available at Industrial Technology Division (BTI/ PAT), Malaysian Nuclear Agency, has a 2.645 year half-life. However, 252 Cf is known to emit gamma radiation from the source. Thus, this chamber aims to provide a proper gamma shielding for samples to distinguish the use of mixed neutron with gamma-rays or pure neutron radiation. The chamber is compatible to be used with other portable neutron sources such as 241 Am-Be as well as the reactor TRIGA PUSPATI for higher neutron dose. This chamber was designed through a collaborative effort of Kulliyyah Engineering, IIUM with the Industrial Technology Division (BTI) team, Malaysian Nuclear Agency. (Author)
People and things. CERN Courier, May 1985, v. 25(4)

Energy Technology Data Exchange (ETDEWEB)

Anon.

1985-05-15

The article reports on achievements of various people, staff changes and position opportunities within the CERN organization and contains news updates on upcoming or past events. A workshop is being arranged to discuss the potential of the CERN SPS proton-antiproton Collider for the early 90s in view of the then simultaneous operation of the Tevatron at Fermilab, LEP at CERN and HERA at DESY, and to evaluate the need for a new Collider detector.
40 CFR 421.254 - Standards of performance for new sources.

Science.gov (United States)

2010-07-01

... property Maximum for any 1 day Maximum for monthly average mg/troy ounce of gold and silver smelted Lead 0... Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver... average mg/troy ounce of gold refined electrolytically Lead 5.544 2.574 Mercury 2.970 1.188 Silver 5.742 2...
TASK 2.5.4 DEVELOPMENT OF AN ENERGY SAVINGS CALCULATOR

Energy Technology Data Exchange (ETDEWEB)

Miller, William A [ORNL; New, Joshua Ryan [ORNL; Desjarlais, Andre Omer [ORNL; Huang, Joe [Lawrence Berkeley National Laboratory (LBNL); Erdem, Ender [Lawrence Berkeley National Laboratory (LBNL); Ronnen, Levinson [Lawrence Berkeley National Laboratory (LBNL)

2010-03-01

California s major energy utilities and the California Energy Commission (CEC) are seeking to allocate capital that yields the greatest return on investment for energy infrastructure that meets any part of the need for reliable supplies of energy. The utilities are keenly interested in knowing the amount of electrical energy savings that would occur if cool roof color materials are adopted in the building market. To meet this need the Oak Ridge National Laboratory and the Lawrence Berkeley National Laboratory (LBNL) have been collaborating on a Public Interest Energy Research (PIER) project to develop an industry-consensus energy-savings calculator. The task was coordinated with an ongoing effort supported by the DOE to develop one calculator to achieve both the DOE and the EPA objectives for deployment of cool roof products. Recent emphasis on domestic building energy use has made the work a top priority by the Department of Energy s (DOE) Building Technologies Program. The Roof Savings Calculator (RSC) tool is designed to help building owners, manufacturers, distributors, contractors and practitioners easily run complex simulations. The latest web technologies and usability design were employed to provide an easy input interface to an annual simulation of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim. Building defaults were assigned based on the best available statistical evidence and can provide energy and cost savings after the user selects nothing more than the building location. A key goal for the tool is to promote the energy benefits of cool color tile, metal and asphalt shingle roof products and other energy saving systems. The RSC tool focuses on applications for the roof and attic; however, the code conducts a whole building simulation that puts the energy and heat flows of the roof and attic into the perspective of the whole house. An annual simulation runs in about 30 sec. In addition to cool reflective roofs, the RSC tool will simulate high- medium- and low-slope roofs, and has a custom selection for the user whose house has a unique inclination. There is an option for above sheathing ventilation, which is prevalent in tile and stone-coated metal roof assemblies. The tool also accommodates the effects of radiant barriers and low-emittance surfaces in the inclined air space above the sheathing. The practitioner can select to have air-conditioning ducts either in the conditioned space or in the attic. If in the attic, the user can select one of three air leakage options. Option 1 is an inspected duct having 4% leakage and code level of duct insulation; option 2 is a poorly insulated duct having 14% air leakage; and option 3 is a custom leakage rate specified by the user. The practitioner can setup multiple layers of ceiling insulation. AtticSim is benchmarked against the field data acquired for Ft. Irwin located near Barstow, CA, first as a standalone simulation program and then again integrated within the DOE-2.1E program. The standalone benchmark was very useful to determining how well AtticSim replicates the building physics of an attic. The coupled benchmark was useful to verify that the DOE-2.1E/AtticSim code is modeling correctly the dynamic relationship between the attic and the occupied space below, as well as the interactions between the attic and the HVAC system, in particular when the ducts are located in the attic.
Monitoring changes in the structure and properties of humic substances following ozonation using UV-Vis, FTIR and (1)H NMR techniques.

Science.gov (United States)

Rodríguez, Francisco J; Schlenger, Patrick; García-Valverde, María

2016-01-15

The main objective of this work is to conduct a comprehensive structural characterization of humic substances using the following experimental techniques: FTIR, 1H NMR and several UV–Vis parameters (Specific UV Absorbance at 254 nm or SUVA254, SUVA280, A400, the absorbance ratios A210/254, A250/365, A254/203, A254/436, A265/465, A270/400, A280/350, A465/665, the Absorbance Slope Index (ASI), the spectral slopes S275–295, S350–400 and the slope ratio SR). These UV–Vis parameters have also been correlated with key properties of humic substances such as aromaticity, molecular weight (MW) and trihalomethane formation potential (THMFP). An additional objective of this work is also to evaluate the usefulness of these techniques to monitor structural changes in humic substances produced by the ozonation treatment. Four humic substances were studied in this work: three of them were provided by the International Humic Substances Society (Suwannee River Fulvic Acid Standard: SRFA, Suwannee River Humic Acid Standard: SRHA and Nordic Reservoir Fulvic Acid Reference: NLFA) and the other one was a terrestrial humic acid widely used as a surrogate for aquatic humic substances in various studies (Aldrich Humic Acid: AHA). The UV–Vis parameters showing the best correlations with aromaticity in this study were SUVA254, SUVA280, A280/A350 ratio and A250/A364 ratio. The best correlations with molecular weight were for SUVA254, SUVA280 and A280/A350 ratio. Finally, in the case of the THMFP it was STHMFP-per mol HS the parameter showing good correlations with most of the UV–Vis parameters studied (especially with A280/A350 ratio, A265/A465 ratio and A270/A400 ratio) whereas STHMFP-per mg C showed poor correlations in most cases. On the whole, the UV–Vis parameter showing the best results was A280/A350 ratio as it showed excellent correlations for the three properties studied (aromaticity, MW and THMFP). A decrease in aromaticity following ozonation of humic substances can
Csapody, Tamás. 2014. Bortól Szombathelyig - Tanulmányok a bori munkaszolgálatról és a bori munkaszolgálatosok részleges névlistája ('From Bor to Szombathely- Studies on the Forced Labor Service at Bor Camp and the Partial List of the Forced Laborers in Bor'. Budapest: Zrinyi Kadó. 254 pp. ; Csapody, Tamás. 2015. A Cservenkai tömeggyilkosság ('The Mass Murder at Cservenka'. Budapest: Zsidó Tudományok Szabadegyeteme Alapítvány. 150 pp.

Directory of Open Access Journals (Sweden)

Julia Bock

2016-10-01

Full Text Available Csapody, Tamás. 2014. Bortól Szombathelyig - Tanulmányok a bori munkaszolgálatról és a bori munkaszolgálatosok részleges névlistája ('From Bor to Szombathely- Studies on the Forced Labor Service at Bor Camp and the Partial List of the Forced Laborers in Bor'. Budapest: Zrinyi Kadó. 254 pp. ; Csapody, Tamás. 2015. A Cservenkai tömeggyilkosság ('The Mass Murder at Cservenka'. Budapest: Zsidó Tudományok Szabadegyeteme Alapítvány. 150 pp. (e-book; a shorter version is accessible at: http://zsido.com/konyvek/a-cservenkai-tomeggyilkossag/.
Time resolution measurements with an improved discriminator and conical scintillators

International Nuclear Information System (INIS)

McGervey, J.D.; Vogel, J.; Sen, P.; Knox, C.

1977-01-01

A new constant fraction discriminator with improved stability and walk characteristics is described. The discriminator was used with RCA C31024 photomultiplier tubes to test scintillators of conical and cylindrical shapes. Conical scintillators of 2.54 cm base diameter, 1.0 cm top diameter, and 2.54 cm height gave a fwhm of 155 ps for 60 Co gamma rays; larger conical scintillators gave an improvement of 10-15% in fwhm over cylindrical scintillators of equal volume. (Auth.)
UV-radiation and the flavonoid content in callus culture of Ononis arvensis L

International Nuclear Information System (INIS)

Tumowa, L.; Psotowa, R.

1998-01-01

The paper discussed a possible influence on the production of secondary metabolites - the flavonoids, by the method of elicitation in the callus cultures of Ononis arvensis L., the elicitor employed being the UV 254 and 366 nm and the sun-lamp. In some cases there was an increase in the production of flavonoids particularly 60, 120, 240 and 300 s after sun-lamp irradiation and in case of 15 and 30 min irradiation with UV-254 nm
Therapeutic Efficacy of the Small Molecule GS-5734 against Ebola virus in Rhesus Monkeys

Science.gov (United States)

2016-03-02

culture. The diastereomeric mixture at phosphorous 858 containing GS-5734 was incubated continuously for 72 h at 1 µM and levels of intracellular NTP...constants (J) in Hertz. Analytical thin–layer chromatography was performed using Merck KGaA Silica gel 60 F254 glassplates with UV visualization. Preparative...trifluoroacetic acid in water and 0.1% trifluoroacetic acid in acetonitrile; flow rate, 2 mL/min; acquisition time, 6 min; wavelength, UV 214 and 254 nm

A preliminary parasitological survey of hepatozoon spp. Infection in dogs in mashhad, iran.

Science.gov (United States)

Amoli, Aa Rahmani; Khoshnegah, J; Razmi, Ghr

2012-01-01

We attempted to determine the prevalence of Hepatozoon spp. infection in Mashhad, northeast of Iran, via blood smear parasitology. The prevalence was investigated by examination of blood smear parasitology, using blood samples collected from 254 dogs (51 strays and 203 privately owned-dogs). Two stray dogs (2/51; 3.92%) and two privately-owned dogs (2/203; 0.98%) were infected with Hepatozoon spp. Therefore, as per blood smear parasitology, the prevalence of Hepatozoon spp. infection was 1.57% (4/254). Sixteen out of 254 dogs (6.29%) were infested with ticks; all of which were Rhipicephalus sanguineus. One of the dogs infected with Hepatozoon spp. exhibited ticks at the time of examination. Concurrent infection with Ehrlichia canis and Leishmania infantum was not detected in the four Hepatozoon spp. infected dogs. This is the first epidemiological study on the prevalence of Hepatozoon spp. infection in dogs in Iran.
Nuclear reactions and the synthesis of new species

International Nuclear Information System (INIS)

Anon.

1983-01-01

Targets of relatively short-lived, neutron-rich transplutonium isotopes, such as 254 Es, which are produced by the HFIR/TRU, when combined with the capabilities of modern heavy-ion accelerators, offer a unique possibility to expand our knowledge of chemical elements and atomic nuclei toward the limits of nuclear stability. This knowledge should enable us to delineate the forces that eventually terminate the periodic table at its upper end. Specifically, the panel concludes that significant research opportunities exist in several areas, which are highlighted below: Nucleon-transfer reactions between light heavy-ion projectiles (such as 18 O, 22 Ne, or 48 Ca) and 254 Es targets will give access to a completely uncharted region of neutron-rich isotopes. Cold-fusion reactions of 48 Ca projectiles with /sup 254,255/Es targets should yield superheavy nuclei with neutron numbers very close to the predicted closed neutron shell at N = 184
Generation of soluble microbial products by bio-activated carbon filter during drinking water advanced treatment and its influence on spectral characteristics

Energy Technology Data Exchange (ETDEWEB)

Shen, Hong, E-mail: song.wei0326@163.com [National Engineering Research Center for Urban Pollution Control, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Chen, Xin, E-mail: 742702437@qq.com [National Engineering Research Center for Urban Pollution Control, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Zhang, Dong, E-mail: zhdongtj7021@sina.com [National Engineering Research Center of Urban Water Resources, Shanghai National Engineering Research Center of Urban Water Resources Co. Ltd, Shanghai 200082 (China); Chen, Hong-bin, E-mail: hbctxc@tongji.edu.cn [National Engineering Research Center for Urban Pollution Control, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

2016-11-01

In order to improve our understanding of bio-activated carbon (BAC) filter, the water quality of influent and effluent treated with BAC in a drinking water treatment plant (DWTP) of Shanghai during 2015 was valued. Combining the results from UV{sub 254}, SUVA{sub 254}, dissolved organic carbon (DOC) and scanning electron microscopic (SEM), it is found that performance of BAC treatment will be affected by characteristics of activated carbon (AC), which is relevant to the type of activated carbon (including shape and operating time) in this study. Fluorescence excitation–emission matrix (FEEM) shows that the humification index (HIX) and index of recent autochthonous contribution (BIX) is a reliable indicator to descript the variation of dissolved organic matter (DOM) during BAC process. The pattern of variation in BIX and HIX implies that soluble microbial products (SMPs) are formed and humic-like substances are removed during BAC treatment, which is also confirmed by the change of peaks of FEEM in BAC effluent. Large, positive correlations between SUVA{sub 254} and disinfection by-products formation potential yield (DBPFP yield) demonstrate that UV-absorbing DOM is directly related to the generation of DBPs. Poor correlations of HIX with DBPFP suggest that non-humic substances with UV-absorbing properties play an important role in the generation of DBPs in water with low SUVA{sub 254}. Finally, strong but negative correlations between BIX and DBPFP suggest that vigorous microbial metabolism of BAC results in a decrease in DBPFP. However, the DBPFP yield will be enhanced for the generation of SMPs by BAC, especially in summer. - Highlights: • SMPs can be produced by BAC during drinking water advanced treatment. • BAC can reduce DBPFP, while there are risks associated with increasing DBPFP yield. • SUVA{sub 254} is strongly correlated with the DBPFP yields. • BIX is strongly correlated with DBPFP and THMFP, but weakly with HAAFP.
Is high prevalence of Vitamin D deficiency evidence for autism disorder?: In a highly endogamous population

Science.gov (United States)

Bener, Abdulbari; Khattab, Azhar O.; Al-Dabbagh, Mohamad M.

2014-01-01

Aim: To determine the association between Vitamin D and autism, and the difference in level of Vitamin D in autism children and control. Design: Case–control study conducted between June 2011 and May 2013, among autism at the Hamad Medical Corporation and controls at the School Health Clinics and Primary Health Care Clinics Subjects and Methods: A total of 254 cases and 254 controls. The Autism Diagnostic Observation Schedule-Generic is a semi-structured, standardized assessment of social interaction, communication, play and imaginative use of materials for individuals suspected of having autism spectrum disorders. Data on clinical manifestations and laboratory, family history, body mass index (BMI) and clinical biochemistry variables including serum 25-hydroxy Vitamin D, calcium, phosphorus and magnesium were obtained. Univariate and multivariate statistical analyzes were performed. Results: Of the total number of 508 children surveyed, 254 of autism and 254 of healthy children were contacted. The mean age (± standard deviation, in years) for autism versus control children was 5.51 ± 1.58 versus 5.76 ± 1.56. There were statistically significant differences between autism and healthy children control subjects with respect to educational level of mother (P = 0.016); occupation of mother (P = 0.005); BMI (P 30 ng/ml). Similarly, of the total 254 of healthy children 8.3% had severe Vitamin D deficiency (30 ng/ml). Furthermore, there was statistically significant differences between autism and control subjects with respect to the serum level of Vitamin D (P = 0.023). Conclusion: The present study revealed that Vitamin D deficiency was higher in autism children compared to healthy children and supplementing infants with Vitamin D might be a safe and more effective strategy for reducing the risk of autism. PMID:25624924
The influence of the wavelength of ultraviolet radiation on survival, mutation induction and DNA repair in irradiated Chinese hamster cells

International Nuclear Information System (INIS)

Zelle, B.; Reynolds, R.J.; Kottenhagen, M.J.; Schuite, A.; Lohmann, P.H.M.

1980-01-01

Chinese hamster ovary cells were used to compare the cytotoxicity and mutagenicity of far-UV radiation emitted by a low-pressure mercury, germicidal lamp (wavelength predominantly 254 nm) with that of near UV radiation emitted by a fluorescent lamp with a continuous spectrum (Westinghouse Sun Lamp), of which only the radiation with wavelengths greater than 290 nm or greater than 310 nm was transmitted to the cells. The radiation effects were compared on the basis of an equal number of pyrimidine dimers, the predominant lesion induced in DNA by far-UV, for the induction of which much more energy is needed with near-UV than with 254-nm radiation. The numbers of dimers induced were determined by a biochemical method detecting UV-endonuclease-susceptible sites. The equivalence of these sites with pyrimidine dimers was established, qualitatively and quantitatively, in studies with enzymic photoreactivation in vitro and chromatographic analysis of dimers. On the basis of induced dimers, more cells were killed by UE 310-nm UV than by UE 290-nm UV; both forms of radiation were more cytotoxic than 254-nm UV when equal numbers of dimers were induced. Moreover, 5-6 times as many mutants were induced per dimer by UE 310-nm UV than by UE 290-nm UV; the latter appeared approximately as mutagenic as 254-nm UV. The differences in lethality and mutagenicity were not caused by differences in repair of dimers: cells with an equal number of dimers induced by either 254-nm or near-UV showed the same removal of sites susceptible to a UV endonuclease specific for dimers, as well as an identical amount of repair replication. The results indicate that near-UV induces, besides pyrimidine dimers, other lesions that appear to be of high biological significance. (orig.)
The Association between Oxidative Stress and Metabolic Syndrome in Adults

OpenAIRE

Chung, So-Won; Kang, Sung-Goo; Rho, Jun-Seung; Kim, Ha-Na; Song, In-Sun; Lee, Yun-Ah; Heo, Soo-Jeong; Song, Sang-Wook

2013-01-01

Background In this Study, we investigated the effects of lifestyle and metabolic syndrome on free oxygen radical levels in men and women in Korea. Methods A total of 254 adults were included in this study from February 2011 to June 2012 at a health promotion center. Information of the lifestyles and presence of metabolic syndrome factors was obtained. Biochemical markers were measured and free oxygen radicals test (FORT) was performed on the blood. Results Of the 254 subjects, 86 (33.9%) had ...
Conversion electron spectroscopy in transfermium nuclei

International Nuclear Information System (INIS)

Herzberg, R.D.

2003-01-01

Conversion electron spectroscopy is an essential tool for the spectroscopy of heavy deformed nuclei. The conversion electron spectrometer SACRED has been used in conjunction with the gas-filled recoil separator RITU to study conversion electron cascades in 254 No. The spectra reveal the ground state rotational bands down to low spin. A detailed analysis of the background seen for 254 No shows that approximately 40% of the decay path goes via excited high K bands which may be built on an isomer. (orig.)
Test Methods for Measuring Material Properties of Composite Materials in all Three Material Axes

Science.gov (United States)

2012-01-24

eccentricities in the test setup. Therefore, the research team purchased a special test fixture for performing out-of-plane tension testing in which the...coated wheels as shown in Figure 6. The 15.2 cm long by 2.54 cm thick blocks were separated into five pieces, each with a length of 2.67 cm using the...composite plate. Figure 6. Blocks reduced to a thickness of 2.54 cm using surface grinder and custom electro plated diamond coated wheels Figure 7
Ultraviolet absorbance as a proxy for total dissolved mercury in streams

Science.gov (United States)

Dittman, J.A.; Shanley, J.B.; Driscoll, C.T.; Aiken, G.R.; Chalmers, A.T.; Towse, J.E.

2009-01-01

Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THgd), DOC concentration and DOC composition, and UV254 absorbance across the three sites over different seasons and flow conditions. Pooling data from all sites, we found a strong positive correlation of THgd to DOC (r2 = 0.87), but progressively stronger correlations of THgd with the hydrophobic acid fraction (HPOA) of DOC (r2 = 0.91) and with UV254 absorbance (r2 = 0.92). The strength of the UV254 absorbance-THgd relationship suggests that optical properties associated with dissolved organic matter may be excellent proxies for THgd concentration in these streams. Ease of sample collection and analysis, the potential application of in-situ optical sensors, and the possibility for intensive monitoring over the hydrograph make this an effective, inexpensive approach to estimate THgd flux in drainage waters. ?? 2009 Elsevier Ltd.
Remoción de sustancias húmicas por coagulación con alumbre

Directory of Open Access Journals (Sweden)

Miller Camargo Valero

1999-09-01

Full Text Available En la búsqueda de mejores condiciones para remover material precursor en la formación de subproductos de desinfección con cloro libre, se encontró que la absorbancia al ultravioleta a 254 nm (AUV 254 nm es un parámetro que puede ser usado como medida no específica para estimar concentraciones de material precursor, específicamente sustancias húmicas, y además, como instrumento de control en las operaciones y procesos previos a la desinfección con cloro libre. El estudio plantea la importancia para que en los ensayos de tratabilidad de agua para potabilización se incluya la AUV 254 nm como parámetro de control, ya que en ensayos de coagulación con alumbre se encontró que la remoción de estas sustancias depende de la dosis de coagulante y el pH de coagulación.
Stretchable microelectrode array using room-temperature liquid alloy interconnects

International Nuclear Information System (INIS)

Wei, P; Ziaie, B; Taylor, R; Chung, C; Higgs, G; Pruitt, B L; Ding, Z; Abilez, O J

2011-01-01

In this paper, we present a stretchable microelectrode array for studying cell behavior under mechanical strain. The electrode array consists of gold-plated nail-head pins (250 µm tip diameter) or tungsten micro-wires (25.4 µm in diameter) inserted into a polydimethylsiloxane (PDMS) platform (25.4 × 25.4 mm 2 ). Stretchable interconnects to the outside were provided by fusible indium-alloy-filled microchannels. The alloy is liquid at room temperature, thus providing the necessary stretchability and electrical conductivity. The electrode platform can withstand strains of up to 40% and repeated (100 times) strains of up to 35% did not cause any failure in the electrodes or the PDMS substrate. We confirmed biocompatibility of short-term culture, and using the gold pin device, we demonstrated electric field pacing of adult murine heart cells. Further, using the tungsten microelectrode device, we successfully measured depolarizations of differentiated murine heart cells from embryoid body clusters
A Preliminary Parasitological Survey of Hepatozoon Spp. Infection in Dogs in Mashhad, Iran

Directory of Open Access Journals (Sweden)

J Khoshnegah

2012-12-01

Full Text Available Background: We attempted to determine the prevalence of Hepatozoon spp. infection in Mashhad, northeast of Iran, via blood smear parasitology.Methods: The prevalence was investigated by examination of blood smear parasitology, using blood samples collected from 254 dogs (51 strays and 203 privately owned-dogs.Results: Two stray dogs (2/51; 3.92% and two privately-owned dogs (2/203; 0.98% were infected with Hepatozoon spp. Therefore, as per blood smear parasitology, the prevalence of Hepatozoon spp. infection was 1.57% (4/254. Sixteen out of 254 dogs (6.29% were infested with ticks; all of which were Rhipicephalus sanguineus. One of the dogs infected with Hepatozoon spp. exhibited ticks at the time of examination. Concurrent infection with Ehrlichia canis and Leishmania infantum was not detected in the four Hepatozoon spp. infected dogs.Conclusion: This is the first epidemiological study on the prevalence of Hepatozoon spp. infection in dogs in Iran.
Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

International Nuclear Information System (INIS)

Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

1981-01-01

Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads mg -1 h -1 +- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads mg -1 h -1 . These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less
Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

International Nuclear Information System (INIS)

Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

1981-01-01

Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads micrograms-1 h-1 +/- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads micrograms-1 h-1. These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less
Communication Received from the Permanent Mission of the Republic of Serbia to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

International Nuclear Information System (INIS)

2012-01-01

The Director General has received a note verbale dated 28 September 2012 from the Permanent Mission of Serbia to the International Atomic Energy Agency providing information on the decision of the Government of Serbia to adhere to the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2 [es
Communication Received from the Permanent Mission of the Republic of Serbia to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

International Nuclear Information System (INIS)

2012-01-01

The Director General has received a note verbale dated 28 September 2012 from the Permanent Mission of Serbia to the International Atomic Energy Agency providing information on the decision of the Government of Serbia to adhere to the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2 [fr
Communication Received from the Permanent Mission of the Republic of Serbia to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

International Nuclear Information System (INIS)

2012-01-01

The Director General has received a note verbale dated 28 September 2012 from the Permanent Mission of Serbia to the International Atomic Energy Agency providing information on the decision of the Government of Serbia to adhere to the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2
UV sensitivity of various solid state detectors

International Nuclear Information System (INIS)

Knezevic, Zeljka; Ranogajec-Komor, Maria; Miljanic, Saveta

2008-01-01

Full text: The light sensitivity is an important characteristic of solid state passive dosimeters used in individual, clinical and environmental dosimetry. Light sensitivity stands for the response directly induced by visible or UV light in a fully annealed material. For the above mentioned applications a negligible light sensitivity is an advantage. However, high light sensitivity and linear response allows the use of detectors as UV dosimeters. For this purpose various TL detectors and the glass element of the RPL dosemeter type SC-1 were systematically investigated after exposure to UV light (254 and 366 nm) as a function of time. The following solid state detectors were investigated relative to TLD-100: Li 2 B 4 O 7 :Cu,Ag,P LiF:Mg,Cu,P, LiF:Mg,Cu,Si, Al 2 O 3 :C and the glass element of RPL dosimeter. UV irradiations were performed with Camag UV lamp at 254 nm and at 366 nm. The illumination times were 5, 10 and 20 minutes. Day light illumination was also carried out at room temperature over time period of several hours up to 2 weeks. The UV light response of each detector was compared to the response obtained after irradiation with 137 Cs. Al 2 O 3 :C, showed high light sensitivity; after 10 minutes illumination with 254 nm UV light the response was equivalent to 130 mGy 137 Cs gamma irradiation. The 254 nm UV response of LiF:Mg,Cu,P (GR-200 A), as well as TLD-700H and Li 2 B 4 O 7 :Cu,Ag,P were proportional to the time of illumination. The responses after 10 min UV illumination were equivalent to 0.001 mGy, 0.01 mGy and 0.1 mGy 137 Cs gamma irradiation, respectively. The complete SC-1 RPL dosimeter is insensitive to light because the glass element is encapsulated in light protected holder throughout the automatic evaluation process following the annealing (irradiation, preheat, readout). The responses of the previously annealed glass element after 20 min illumination with 254 nm and 366 nm UV light were equivalent to 45μSv and 3 μSv of 137 Cs gamma
Dissolved organic matter removal using magnetic anion exchange resin treatment on biological effluent of textile dyeing wastewater.

Science.gov (United States)

Fan, Jun; Li, Haibo; Shuang, Chendong; Li, Wentao; Li, Aimin

2014-08-01

This study investigated the removal of dissolved organic matter (DOM) from real dyeing bio-treatment effluents (DBEs) with the use of a novel magnetic anion exchange resin (NDMP). DOMs in two typical DBEs were fractionized using DAX-8/XAD-4 resin and ultrafiltration membranes. The hydrophilic fractions and the low molecular weight (MW) (50%) of DOMs for the two effluents. The hydrophilic and low MW fractions of both effluents were the greatest contributors of specific UV254 absorbance (SUVA254), and the SUVA254 of DOM fractions decreased with hydrophobicity and MW. Two DBEs exhibited acute and chronic biotoxicities. Both acute and chronic toxicities of DOM fractions increased linearly with the increase of SUVA254 value. Kinetics of dissolved organic carbon (DOC) removal via NDMP treatment was performed by comparing it with that of particle active carbon (PAC). Results indicated that the removal of DOC from DBEs via NDMP was 60%, whereas DOC removals by PAC were lower than 15%. Acidic organics could be significantly removed with the use of NDMP. DOM with large MW in DBE could be removed significantly by using the same means. Removal efficiency of NDMP for DOM decreased with the decrease of MW. Compared with PAC, NDMP could significantly reduce the acute and chronic bio-toxicities of DBEs. NaCl/NaOH mixture regenerants, with selected concentrations of 10% NaCl (m/m)/1% NaOH (m/m), could improve desorption efficiency. Copyright © 2014. Published by Elsevier B.V.
Actinopolyspora biskrensis sp. nov., a novel halophilic actinomycete isolated from Northern Sahara.

Science.gov (United States)

Saker, Rafika; Bouras, Noureddine; Meklat, Atika; Zitouni, Abdelghani; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

2015-03-01

A novel halophilic, filamentous actinomycete, designated H254(T), was isolated from a Saharan soil sample collected from Biskra (Northern Sahara), and subjected to a polyphasic taxonomic characterization. The strain is Gram-positive, aerobic, and halophilic, and the optimum NaCl concentration for growth is 15-20 % (w/v). The cell-wall hydrolysate contained meso-diaminopimelic acid, and the diagnostic whole-cell sugars were arabinose and galactose. The diagnostic phospholipid detected was phosphatidylcholine, and MK-9(H4) was the predominant menaquinone. The major fatty acid profiles were anteiso-C17:0 (32.8 %), C15:0 (28 %), and iso-C17:0 (12.3 %). Comparative analysis of the 16S rRNA gene sequences revealed that the strain H254(T) formed a well-separated sub-branch within the radiation of the genus Actinopolyspora, and the microorganism was most closely related to Actinopolyspora saharensis DSM 45459(T) (99.2 %), Actinopolyspora halophila DSM 43834(T) (99.1 %), and Actinopolyspora algeriensis DSM 45476(T) (99.0 %). Nevertheless, the strain had relatively lower mean values for DNA-DNA relatedness with the above strains (57.2, 68.4, and 45.6 %, respectively). Based on phenotypic features and phylogenetic position, we propose that strain H254(T) represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora biskrensis sp. nov. is proposed. The type strain of A. biskrensis is strain H254(T) (=DSM 46684(T) =CECT 8576(T)).

Photoprotective role of epidermal melanin granules against ultraviolet damage and DNA repair in guinea pig skin

International Nuclear Information System (INIS)

Ishikawa, T.; Kodama, K.; Matsumoto, J.; Takayama, S.

1984-01-01

We previously developed a quantitative autoradiographic technique with special forceps for measuring unscheduled DNA synthesis (UDS) in mouse skin after treatment with ultraviolet light in vivo. By this method, we investigated the relationship between the protective role of melanin and UV-induced DNA repair in black-and-white guinea pigs. Flat areas containing a sharp border between pigmented and unpigmented skin were selected. The skin of the selected areas was shaved and irradiated with short-wave UV (254 nm) or UV-AB (270 to 440 nm, emission peak at 312 nm) at various doses. Immediately after irradiation, the skin was clamped off with forceps, and an isotonic aqueous solution of [methyl- 3 H]thymidine was injected s.c. into the clamped off portion. UDS was clearly demonstrated as silver grains in this portion of the skin after irradiation with 254 nm UV or UV-AB. Errors due to individual differences were avoided by comparing the intensities of UDS in basal cells from pigmented skin and unpigmented skin of the same animals. Unexpectedly, in groups of animals treated with 254 nm UV or UV-AB, no difference in UDS in pigmented and unpigmented skin was seen at any UV dose. These results suggested that epidermal melanin granules do not significantly protect DNA of basal cells against 254 nm UV or UV-AB irradiation. Results of a study on the effect of the wavelength of irradiation on the UDS response of albino guinea pigs are also reported
ORF Alignment: NC_003888 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... Length = 309 ... Query: 254 LRPGEQVQIDTTRLDIMAILEDGSLGRPELTIAVDVATRSILAAVLRPYSTKAVDAALLL 313 ... LRPGEQVQIDTTRLDIMAIL...EDGSLGRPELTIAVDVATRSILAAVLRPYSTKAVDAALLL Sbjct: 1 ... LRPGEQVQIDTTRLDIMAILEDGSLGRPELTIAVDVA
ORF Alignment: NC_006350 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available 98 ... Query: 254 IVAAARDYVLAHRSRPVGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD 313 ... IVAAARDYVLAHRSRP...VGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD Sbjct: 1 ... IVAAARDYVLAHRSRPVGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD 60 ...
Communication Received from the PermanentMission of Mexico to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-06-19

The Director General has received a note verbale dated 15 June 2012 from the Permanent Mission of Mexico to the International Atomic Energy Agency providing information on the decision of the Government of Mexico to act in accordance with the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2.
Communication Received from the Permanent Mission of Mexico to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-06-19

The Director General has received a note verbale dated 15 June 2012 from the Permanent Mission of Mexico to the International Atomic Energy Agency providing information on the decision of the Government of Mexico to act in accordance with the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2.
Communication Received from the Permanent Mission of Mexico to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

International Nuclear Information System (INIS)

2012-01-01

The Director General has received a note verbale dated 15 June 2012 from the Permanent Mission of Mexico to the International Atomic Energy Agency providing information on the decision of the Government of Mexico to act in accordance with the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2
Communication Received from the PermanentMission of Mexico to the International Atomic Energy Agency Regarding Guidelines for the Export of Nuclear Material, Equipment and Technology and the Guidelines for Transfers of Nuclear-related Dual-use Equipment, Materials, Software and Related Technology

International Nuclear Information System (INIS)

2012-01-01

The Director General has received a note verbale dated 15 June 2012 from the Permanent Mission of Mexico to the International Atomic Energy Agency providing information on the decision of the Government of Mexico to act in accordance with the 'Guidelines for the Export of Nuclear Material, Equipment and Technology', issued as document INFCIRC/254/Rev.10/Part 1, including its Annexes, and with the 'Guidelines for Transfers of Nuclear-Related Dual-Use Equipment, Material, Software and Related Technology', issued as document INFCIRC/254/Rev.8/Part 2
1397-1403suppl.doc

Indian Academy of Sciences (India)

2. 2.92. 2.44. 1.25. 2.54. 3.66. C57B3. 2.97. 2.44. 1.25. 2.54. 3.49. C60. LiAlH4. 2.91. 2.60. 1.64. 2.36. 3.37. C59B. 2.76. 2.63. 1.63. 2.36. 3.47. C58B2. 2.80. 2.64. 1.65. 2.32. 3.49. C57B3. 2.72. 2.61. 1.64. 2.32. 3.47. C60. LiBH4. 2.20. 2.20. 1.26.
AAS determination of total mercury content in environmental samples

International Nuclear Information System (INIS)

Moskalova, M.; Zemberyova, M.

1997-01-01

Two methods for determination of total mercury content in environmental samples soils, and sediments, were compared. Dissolution procedure of soils, sediments, and biological material under elevated pressure followed by determination of mercury by cold vapour atomic absorption spectrometry using a MHS-1 system and direct total mercury determination without any chemical pretreatment from soil samples using a Trace Mercury Analyzer TMA-254 were compared. TMA-254 was also applied for the determination of mercury in various further standard reference materials. Good agreement with certified values of environmental reference materials was obtained. (authors)
Reflective optical imaging system for extreme ultraviolet wavelengths

Science.gov (United States)

Viswanathan, V.K.; Newnam, B.E.

1993-05-18

A projection reflection optical system has two mirrors in a coaxial, four reflection configuration to reproduce the image of an object. The mirrors have spherical reflection surfaces to provide a very high resolution of object feature wavelengths less than 200 [mu]m, and preferably less than 100 [mu]m. An image resolution of features less than 0.05-0.1 [mu]m, is obtained over a large area field; i.e., 25.4 mm [times] 25.4 mm, with a distortion less than 0.1 of the resolution over the image field.
ORF Alignment: NC_004461 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available AIVKGYFADQLQQYFLSHGVSSAIIDLGGNVLTIGRQPETLE 180 ... Query: 254 ASVTIISDHGIDGEVWSTICSFGQSQKNIELLNLIDGIEGIIVTRDGSV...LMTSKMQKY 311 ... ASVTIISDHGIDGEVWSTICSFGQSQKNIELLNLIDGIEGIIVTRDGSVLMTSKMQKY Sbjct: 241 ASVTIISDHGIDGEVWSTICSFGQSQKNIELLNLIDGIEGIIVTRDGSVLMTSKMQKY 298
Generation of soluble microbial products by bio-activated carbon filter during drinking water advanced treatment and its influence on spectral characteristics

International Nuclear Information System (INIS)

Shen, Hong; Chen, Xin; Zhang, Dong; Chen, Hong-bin

2016-01-01

In order to improve our understanding of bio-activated carbon (BAC) filter, the water quality of influent and effluent treated with BAC in a drinking water treatment plant (DWTP) of Shanghai during 2015 was valued. Combining the results from UV_2_5_4, SUVA_2_5_4, dissolved organic carbon (DOC) and scanning electron microscopic (SEM), it is found that performance of BAC treatment will be affected by characteristics of activated carbon (AC), which is relevant to the type of activated carbon (including shape and operating time) in this study. Fluorescence excitation–emission matrix (FEEM) shows that the humification index (HIX) and index of recent autochthonous contribution (BIX) is a reliable indicator to descript the variation of dissolved organic matter (DOM) during BAC process. The pattern of variation in BIX and HIX implies that soluble microbial products (SMPs) are formed and humic-like substances are removed during BAC treatment, which is also confirmed by the change of peaks of FEEM in BAC effluent. Large, positive correlations between SUVA_2_5_4 and disinfection by-products formation potential yield (DBPFP yield) demonstrate that UV-absorbing DOM is directly related to the generation of DBPs. Poor correlations of HIX with DBPFP suggest that non-humic substances with UV-absorbing properties play an important role in the generation of DBPs in water with low SUVA_2_5_4. Finally, strong but negative correlations between BIX and DBPFP suggest that vigorous microbial metabolism of BAC results in a decrease in DBPFP. However, the DBPFP yield will be enhanced for the generation of SMPs by BAC, especially in summer. - Highlights: • SMPs can be produced by BAC during drinking water advanced treatment. • BAC can reduce DBPFP, while there are risks associated with increasing DBPFP yield. • SUVA_2_5_4 is strongly correlated with the DBPFP yields. • BIX is strongly correlated with DBPFP and THMFP, but weakly with HAAFP.
Spectroscopy of odd-proton nuclei in the region of 254No

International Nuclear Information System (INIS)

Ketelhut, S.; Greenlees, P. T.; Eeckhaudt, S.; Jones, P.; Julin, R.; Juutinen, S.; Kettunen, H.; Leino, M.; Leppaenen, A.-P.; Nieminen, P.; Nyman, M.; Perkowski, J.; Rahkila, P.; Saren, J.; Scholey, C.; Uusitalo, J.; Chatillon, A.; Bouchez, E.; Clement, E.; Goergen, A.

2008-01-01

Two rotational bands have been found in the transfermium nuclei 251 Md and 255 Lr, the latter being the heaviest nucleus so far studied in-beam. Both are assigned to a [521]1/2 - Nilsson state by comparison to theory. The experiments have been carried out in the Accelerator Laboratory of the University of Jyvaeskylae (JYFL), where the array of germanium detectors JUROGAM was used in conjunction with the recoil-seperator RITU and the focal-plane setup GREAT for gamma-spectroscopic studies
30 CFR 254.42 - Exercises for your response personnel and equipment.

Science.gov (United States)

2010-07-01

..., communication, and decisionmaking in managing a response. You must not reveal the spill scenario to team members... the complete 3-year exercise cycle. Records should be maintained at the facility or at a corporate...
: tous les projets | Page 254 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

La production de petits mils, en dépit des vertus nutritionnelles de cette céréale, de sa capacité de croître dans des conditions difficiles et de sa facilité de stockage, a toujours été négligée par les politiques agricoles déployées en Asie du Sud. Ces dernières, en effet, ont privilégié les cultures de rente et les céréales comme ...
Peculiarities of near-ultraviolet (365 nm) and visible light effects in Paramecium Caudatum cells

International Nuclear Information System (INIS)

Samoilova, K.A.; Sushchenko, N.B.

1977-01-01

After treatment with 365 nm or visible light Paramecium caudatum cells fail to divide and die shortly after irradiation; no death occurs long after irradiation, as well as after several cell cycles, unlike the situation after the action of 254 nm or 300-380 nm. Irradiation inhibits mainly the first cell cycle following which the recovery of cells starts. Thus no after-effects take place after the action of 365 nm and visible light, and the patterns of their effects are rather similar. The photoreactivation of damages induced by 365 nm is quite small, being about 2 times less than that for 254 nm and 300-380 nm. Similarity of the action of 254, 300-380, 365 nm and visible light was established by the stimulation of cell division by low doses and increase in viability of infusoria from cultures with low survival and depressed rate of multiplication. This effect of 365 nm is not eliminated by visible light; moreover, the latter promotes the 'therapeutic' effect of the 365 nm line. (author)
Effects of ultraviolet radiation on the survival and metabolic end products of Bacteroides melaninogenicus

International Nuclear Information System (INIS)

Smith-Kappus, S.D.

1987-01-01

In experiments investigating DNA repair, it was shown that B. melaninogenicus does not repair UV light induced damage via photoreactivation. Survival curves constructed for the organism after exposure to UV light at 254 nm and 365 nm under aerobic and anaerobic conditions while the organisms were in exponential or stationary growth phase, revealed that the cells were most sensitive to UV induced damage when exposed to radiation while in the exponential growth phase under aerobic conditions at either wavelength. B. melaninogenicus exposed to UV light under anaerobic conditions while the cells were in stationary growth phase were much more sensitive to UV induced damage at 254 nm than cells irradiated under the same conditions at 365 nm UV. Survival studies of B. melaninogenicus after co-insult with UV light and subinhibitory concentrations of chloramphenicol, metronidazole, caffeine, or fluoroacetate, at 254 nm UV or 365 nm UV, under aerobic and anaerobic atmospheric conditions illustrated a decreased shoulder region on the curves, particularly after 365 nm UV exposure, when compared to UV irradiation applied without subsequent chemical treatment
Near-ultraviolet radiation blocks SOS responses to DNA damage in Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Turner, M.A.; Eisenstark, A.

1984-01-01

Escherichia coli cells in which the recA promoter is fused to a lac structural gene, (Mu) Mud(Ap,lac)::rec, were irradiated with two far-ultraviolet light wavelengths (254 and 290 nm), selected monochromatic near-ultraviolet (NUV) wavelengths 313 nm, 334 nm, 365 nm, or broad band solar-UV (290-420 nm) from a solar simulator. Irradiation with the two far-ultraviolet wavelengths was followed by high yields of ..beta..-galactosidase, lambda prophage induction, and Weigle reactivation. These end points were not observed after irradiation with the selected NUV wavelengths or the broad spectrum solar-UV. Thus, neither broad spectrum solar-UV nor monochromatic NUV wavelengths resulted in the derepression of the recA promoter. Further, prior exposure of the cells either to the selected monochromatic NUV wavelengths or to solar-UV inhibited a) the induction of ..beta..-galactosidase by subsequent 254-nm radiation, b) subsequent 254-nm induction of lambda prophage, c) Weigle reactivation, and d) mutation frequency. These observations are consistent with the hypothesis that NUV blocks subsequent recA protease action.
A radiographic study on the condylar position in temporomandibular joint dysfunction patients

International Nuclear Information System (INIS)

Bang, Seo Howan; Kim, Jae Duck

1987-01-01

The author obtained the transcranial-oblique lateral radiograms from 78 patients (26 male, 52 female) with temporom andibular dysfunction problem. And then, the author analyzed the dimensional changes of the TMJ space on centric occlusion, horizontal condylar movement and antero-posterior positional relationship of condyle to the articular eminence on 2.54 cm mouth opening with clicking, TMJ pain and mouth opening limitation respectively, which were the symptoms of the temporomandibular joint pain dysfunction problem, and compared these data with control group. The results were as follow: 1. In centric occlusion, anterior and posterior TMJ space of experimental group was slightly lesser than those of the control group, also superior TMJ space of experimental group was significantly lesser than that of the control group. (p 2. In 2.54 cm mouth opening, the condylar horizontal movement and the antero-posterior positional relationship to the articular eminence were significantly lesser than those of the control group. (p 3. Examined experimental group, the degree of condylar horizontal movement of affected side was lesser than that of the normal side in 2.54 cm mouth opening.
Oxygen-independent inactivation of Haemophilus influenzae transforming DNA by monochromatic radiation: action spectrum, effect of histidine and repair

Energy Technology Data Exchange (ETDEWEB)

Cabrera-Juarez, E; Setlow, J K; Swenson, P A; Peak, M J

1976-01-01

The action spectrum for the oxygen-independent inactivation of native transforming DNA from Haemophilus influenzae with near-uv radiation revealed a shoulder beginning at 334 and extending to 460 nm. The presence of 0.2 M histidine during irradiation produced a small increase in inactivation at 254, 290 and 313 nm, a large increase at 334 nm and a decrease in inactivation at 365, 405, and 460 nm. Photoreactivation did not reverse the DNA damage produced at pH 7.0 at 334, 365, 405 and 460 nm, but did reactivate the DNA after irradiation at 254, 290 and 313 nm. The inactivation of DNA irradiated at 254, 290 and 313 nm was considerably greater when the transforming ability was assayed in an excision-defective mutant compared with the wild type, although DNA irradiated at 334, 365, 405 and 460 nm showed smaller differences. These results suggest that the oxygen-independent inactivation of H. influenzae DNA at pH 7 by irradiation at 334, 365, 405 and 460 nm is caused by lesions other than pyrimidine dimers.

Lethal effects of solar radiation in proficient and deficient bacteria in repair systems

International Nuclear Information System (INIS)

Sousa Neto, A. de.

1980-01-01

A study of the lethal action of solar radiation on strains of E.coli K12, proficient or deficient in repair systems, as well as the wild type strain gene products are involved in repair of damage induced by solar radiation. The inactivation of the various bacterial strains (normalized to a dose equivalent to radiation at a wavelength 254 nm) suggests that the more energetic wavelengths of the solar spectrum (290-320 nm) could be responsible for the primary damage that occurs in the DNA. The reduction in the shoulder of the survival curve in wild type strains in indicative of induction of sub-lethal damage in this region of the curve. Analysing solar inactivation curves of the bacterial strains (normalised by spore dosimetry) together with those of the same strains irradiated with UV at 254 nm, it was evident that 254 nm is not the ideal wavelength for comparison. This analysis also indicated that in addition to damage to DNA, other factors are involved in the solar radiation inactivation of wild type strains. (author)
UV-induced changes in cell cycle and gene expression within rabbit lens epithelial cells

International Nuclear Information System (INIS)

Sidjanin, D.; Grdina, D.; Woloschak, G.E.

1996-01-01

Damage to lens epithelial cells is a probable initiation process in cataract formation mediated by UV radiation. In these experiments, we investigated the effects of exposure to 254 nm radiation on cell cycle progression in the rabbit lens epithelial cell line N/N1003A. The RNA was harvested at various times following exposure to UV (254 nm) radiation and analyzed by dot-blot and northern blot hybridizations. These results revealed that during the first 6 h following exposure of the cells to UV, there was, associated with decreasing dose, a decrease in accumulation of transcripts specific for histones H3 and H4 and an increase in the mRNA encoding protein kinase C and β- and γ-actin. Using flow cytometry, we detected an accumulation of cells in G1/S phase of the cell cycle 1 h following exposure to 254 nm radiation. The observed changes in gene expression, especially the decreased accumulation of histone transcripts reported here, may play a role in UV-induced inhibition of cell cycle progression. (Author)
Ultraviolet absorbance as a proxy for total dissolved mercury in streams

International Nuclear Information System (INIS)

Dittman, Jason A.; Shanley, James B.; Driscoll, Charles T.; Aiken, George R.; Chalmers, Ann T.; Towse, Janet E.

2009-01-01

Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THg d ), DOC concentration and DOC composition, and UV 254 absorbance across the three sites over different seasons and flow conditions. Pooling data from all sites, we found a strong positive correlation of THg d to DOC (r 2 = 0.87), but progressively stronger correlations of THg d with the hydrophobic acid fraction (HPOA) of DOC (r 2 = 0.91) and with UV 254 absorbance (r 2 = 0.92). The strength of the UV 254 absorbance-THg d relationship suggests that optical properties associated with dissolved organic matter may be excellent proxies for THg d concentration in these streams. Ease of sample collection and analysis, the potential application of in-situ optical sensors, and the possibility for intensive monitoring over the hydrograph make this an effective, inexpensive approach to estimate THg d flux in drainage waters. - Ultraviolet absorbance measurements are a cost-effective proxy to estimate dissolved mercury concentration in stream water.
Damage to UV-sensitive cells by short UV in photographic flashes

International Nuclear Information System (INIS)

Menezes, S.; Monteiro, C.

1996-01-01

Light emitted by electronic photographic flash units is shown to damage bacteria and human skin fibroblasts deficient in repair systems, with survival curves very similar to those produced by 254 nm short UV. The lesions induced by these flashes are as photorepairable by the photolyase enzyme as those induced by 254 nm UV and result in equivalent survival rates. Biological dosimetry performed with microorganisms highly sensitive to UV (Escherichia coli K12 AB2480, deficient in excision and recombinational-dependent repair systems and Bacillus subtilis UVSSP spores, deficient in excision and in a specific spore repair process) revealed that each 1 ms flash of light from the photographic unit used in this work contained the equivalent of 0.25 J m -2 of 254 nm UV, when measured at a distance of 7.0 cm. This dose of UV was found to be lethal to both repair-deficient E. coli bacteria and repair-deficient human skin fibroblasts obtained from xeroderma pigmentosum donors, as well as mutagenic in B/r wild-type and HCR-mutant bacteria. (Author)
Lethal effects of solar radiation in proficient and deficient bacteria in repair systems; Efeitos letais da luz solar em bacterias proficientes e deficientes em reparos: acoes e interacoes

Energy Technology Data Exchange (ETDEWEB)

Sousa Neto, A de

1981-12-31

A study of the lethal action of solar radiation on strains of E.coli K12, proficient or deficient in repair systems, as well as the wild type strain gene products are involved in repair of damage induced by solar radiation. The inactivation of the various bacterial strains (normalized to a dose equivalent to radiation at a wavelength 254 nm) suggests that the more energetic wavelengths of the solar spectrum (290-320 nm) could be responsible for the primary damage that occurs in the DNA. The reduction in the shoulder of the survival curve in wild type strains in indicative of induction of sub-lethal damage in this region of the curve. Analysing solar inactivation curves of the bacterial strains (normalised by spore dosimetry) together with those of the same strains irradiated with UV at 254 nm, it was evident that 254 nm is not the ideal wavelength for comparison. This analysis also indicated that in addition to damage to DNA, other factors are involved in the solar radiation inactivation of wild type strains. (author).
In-situ elemental analysis of coal by neutron activation

International Nuclear Information System (INIS)

Mikesell, J.L.; Senftle, F.E.; Tanner, A.B.

1986-01-01

The U.S. Geological Survey (USGS) has worked to develop neutron techniques for the borehole measurement of the elemental composition of ores since 1969, and first demonstrated a borehole ultimate analysis of coal in 1977. Borehole measurements such as these permit real-time evaluation of coal quality without the expense of coring or the delays associated with laboratory analyses. Two technological innovations make such measurements possible: the availability, from Savannah River Operations Office, DOE, of small californium-252 (/sup 252/Cf) fission neutron sources, and the development, by USGS and Princeton Gamma-Techn, of the melting-cryogen-cooled high-purity germanium borehole gamma-ray detector. A technique of relating mass fractions to measured gamma-ray intensities, which eliminates the need for detailed knowledge of the geometry of the neutron distribution, is used to calculate elemental compositions without resorting to the test pits or computer borehole modeling. In coal, all of the major constituents (C, H, N, S, Si, Al, Fe, Ti) except oxygen can be determined quantitatively by thermal neutron capture gamma-ray spectroscopy
Report on the workshop "Decay spectroscopy at CARIBU: advanced fuel cycle applications, nuclear structure and astrophysics". 14-16 April 2011, Argonne National Laboratory, USA.

Energy Technology Data Exchange (ETDEWEB)

Kondev, F.; Carpenter, M.P.; Chowdhury, P.; Clark, J.A.; Lister, C.J.; Nichols, A.L.; Swewryniak, D. (Nuclear Engineering Division); (Univ. of Massachusetts); (Univ. of Surrey)

2011-10-06

A workshop on 'Decay Spectroscopy at CARIBU: Advanced Fuel Cycle Applications, Nuclear Structure and Astrophysics' will be held at Argonne National Laboratory on April 14-16, 2011. The aim of the workshop is to discuss opportunities for decay studies at the Californium Rare Isotope Breeder Upgrade (CARIBU) of the ATLAS facility with emphasis on advanced fuel cycle (AFC) applications, nuclear structure and astrophysics research. The workshop will consist of review and contributed talks. Presentations by members of the local groups, outlining the status of relevant in-house projects and availabile equipment, will also be organized. time will also be set aside to discuss and develop working collaborations for future decay studies at CARIBU. Topics of interest include: (1) Decay data of relevance to AFC applications with emphasis on reactor decay heat; (2) Discrete high-resolution gamma-ray spectroscopy following radioactive decya and related topics; (3) Calorimetric studies of neutron-rich fission framgents using Total ABsorption Gamma-Ray Spectrometry (TAGS) technique; (4) Beta-delayed neutron emissions and related topics; and (5) Decay data needs for nuclear astrophysics.
Time-of-flight mass spectrometry with desorption-ionization multiprobes (UV photons and KeV and MeV particles). Cluster atoms are used as projectiles

International Nuclear Information System (INIS)

Brunelle, A.

1990-09-01

A new time-of-flight mass spectrometer, Super-Depil, is used to study secondary ion emission from solid surfaces bombarded by various kinds of primary particles. Three different desorption probes were set up on this machine: a 252 californium source, providing by spontaneous fission about 1 MeV/u energy heavy ions, a 5 to 30 keV energy pulsed caesium ion gun and a pulsed nitrogen laser, which wavelength is 337 mm. A two stages electrostatic mirror was added to the spectrometer. The time spread due to the initial kinetic energy of secondary ions leaving the surface was minimized. The mass resolution is greater than 5000. The analysis of glycosidic terpenes showed the complementarity of the three probes. The study of such metastable ions, with the electrostatic mirror, showed that some fragment ions may conserve the memory of the stereochemistry of the neutral lost. Clusters ions were used as projectiles in the energy range 5-60 keV. A strong non linear enhancement was observed in the secondary ion yield from various targets [fr
Peculiarities of extraction of carbonate complexes of trivalent transplutonium elements by alkylpyrocatechins

International Nuclear Information System (INIS)

Karalova, Z.K.; Bukina, T.I.; Myasoedov, B.F.; Fedorov, L.A.; Sokolovskij, S.A.

1987-01-01

Extraction of trivalent americium, curium, californium and europium by technical mixture of mono- and didecylpyrocatechin (TAP) in various diluents from carbonate solutions is investigated. Effect of many factors (pH, K 2 CO 3 concentration, TAP, metal; the time of phase contact) on the completeness of element isolation and separation is clarified. It is ascertained that the elements listed are quantitatively extracted by TAP solution in toluene and cyclohexane in the range of K 2 CO 3 concentrations from 0.25 to 1.5 mol/l. The difference in americium and curium distribution coefficient during their extraction by TAP from 0.25 mol/l of K 2 CO 3 solution is detected. Separation coefficients of the pair increase with the increase of carbonate solution pH. The separation can be improved at the stage of element reextraction by the mixture of K 2 CO 3 and DTPA or EDTA from alkylpyrocatechin, sunce rate constants of americium and curium reextraction differ greatly. Using 13 C NMR the composition of compounds in organic phase on the basis of 4-(α, α-dioctylethyl)pyrocatechin is investigated
Fast neutron tomography with real-time pulse-shape discrimination in organic scintillation detectors

Energy Technology Data Exchange (ETDEWEB)

Joyce, Malcolm J., E-mail: m.joyce@lancaster.ac.uk [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom); Agar, Stewart [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom); Aspinall, Michael D. [Hybrid Instruments Ltd., Gordon Manley Building, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YW (United Kingdom); Beaumont, Jonathan S.; Colley, Edmund; Colling, Miriam; Dykes, Joseph; Kardasopoulos, Phoevos; Mitton, Katie [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom)

2016-10-21

A fast neutron tomography system based on the use of real-time pulse-shape discrimination in 7 organic liquid scintillation detectors is described. The system has been tested with a californium-252 source of dose rate 163 μSv/h at 1 m and neutron emission rate of 1.5×10{sup 7} per second into 4π and a maximum acquisition time of 2 h, to characterize two 100×100×100 mm{sup 3} concrete samples. The first of these was a solid sample and the second has a vertical, cylindrical void. The experimental data, supported by simulations with both Monte Carlo methods and MATLAB®, indicate that the presence of the internal cylindrical void, corners and inhomogeneities in the samples can be discerned. The potential for fast neutron assay of this type with the capability to probe hydrogenous features in large low-Z samples is discussed. Neutron tomography of bulk porous samples is achieved that combines effective penetration not possible with thermal neutrons in the absence of beam hardening.
[Fast neutron cross section measurements]: Progress report

International Nuclear Information System (INIS)

1988-01-01

As projected in our previous proposal, the past year on the cross section project at the University of Michigan has been one primarily of construction and assembly of our 14 MeV pulsed Neutron Facility. All the components of the system have now been either purchased or fabricated in our shop facilities and have been assembled in their final configuration. We are now in the process of testing the rf components that have been designed to deliver voltage to both the pulser and buncher stages. We expect that the system will be operational by the end of the current contract year. We have also accomplished the design and construction of several other major pieces of equipment that are needed to begin fast neutron time-of-flight measurements. These include the primary proton recoil detector, and a californium fission chamber needed in the efficiency calibration of the primary detector. We have also added considerable concrete shielding designed to lower the neutron background in the experimental area. 10 figs., 5 tabs
Estimation of the sub-criticality of the sodium-cooled fast reactor Monju using the modified neutron source multiplication method

International Nuclear Information System (INIS)

Truchet, G.; Van Rooijen, W. F. G.; Shimazu, Y.; Yamaguchi, K.

2012-01-01

The Modified Neutron Source Method (MNSM) is applied to the Monju reactor. This static method to estimate sub-criticality has already given good results on commercial Pressurized Water Reactors. The MNSM consists both in the extraction of the fundamental mode seen by a detector to avoid the effect of higher modes near sources, and the correction of flux distortion effects due to control rod movement. Among Monju's particularities that have a big influence on MNSM factors are: the presence of two californium sources and the position of the detector which is located far from the core outside of the reactor vessel. The importance of spontaneous fission and (α, n) reactions which have increased during the shutdown period of 15 years will also be discussed. The relative position of detectors and sources deeply affect the correction factors in some regions. In order to evaluate the detector count rate, an analytical propagation has been conducted from the reactor vessel. For two subcritical states, an estimation of the reactivity has been made and compared to experimental data obtained in the restart experiments at Monju (2010). (authors)
Measurement of neutron dose and spectra at light-water reactors

International Nuclear Information System (INIS)

Soldat, K.L.; Endres, G.W.R.; Cummings, F.M.

1982-08-01

In choosing one dosimeter over another, both sensitivity and precision must be addressed. It has been determined that dosimeters employing NTA film lack adequate sensitivity for use inside containment of nuclear plants. From this study, it is apparent that CR-39 and polycarbonate track etch films used without radiators are also inadequate. The rest of the dosimeters tested displayed adequate sensitivity. The two general types of dosimeters which comprise that group are: (1) TLDs and (2) the polycarbonate track etch which was used in conjunction with (n, α) radiators. The precision of the TLD dosimeter depends on the calibration technique and response correction technique. TLD dosimeters calibrated to D 2 O-moderated californium-252 or corrected based on 9- to 3-in. sphere response rates seemed to function best inside reactor containment. Polycarbonate track etch film with (n, α) radiators was found to be sensitive enough for use inside reactor containment; however, the standard deviation for the results was roughly twice the value of the most precise TLD albedo dosimeters. Also, several of the polycarbonate dosimeters saturated, rendering any evaluation impossible
Development of an analytical theory to describe the PNAR and CIPN nondestructive assay techniques

International Nuclear Information System (INIS)

Bolind, Alan Michael

2014-01-01

Highlights: • Neutron albedo is modeled by a discrete and iterative reflection process. • The theory enables the PNAR and CIPN NDA techniques to be compared quantitatively. • Improvements to the data analysis and to the CIPN instrument design are suggested. • A correction to translate real no-reflection PNAR data into ideal data is provided. - Abstract: This paper develops an analytical theory to describe how neutron albedo (reflection) increases the multiplication of neutrons by a used fuel assembly. With this theory, the two nondestructive assay (NDA) techniques of Passive Neutron Albedo Reactivity (PNAR) and Californium-252 Interrogation with Prompt Neutron Detection (CIPN) can be compared directly. Specifically, the theory derives expressions for the PNAR and CIPN metrics in terms of the physical properties of the used fuel assembly, such as the neutron multiplications and fate probabilities. The theory thus clarifies the interpretation of these two NDA techniques and suggests ways to improve both the design of the NDA instruments and the algorithms for analyzing the measurement results
Robotics at Savannah River site: activity report

International Nuclear Information System (INIS)

Byrd, J.S.

1984-09-01

The objectives of the Robotics Technology Group at the Savannah River Laboratory are to employ modern industrial robots and to develop unique automation and robotic systems to enhance process operations at the Savannah River site (SRP and SRL). The incentives are to improve safety, reduce personnel radiation exposure, improve product quality and productivity, and to reduce operating costs. During the past year robotic systems have been installed to fill chemical dilution vials in a SRP laboratory at 772-F and remove radioactive waste materials in the SRL Californium Production Facility at 773-A. A robotic system to lubricate an extrusion press has been developed and demonstrated in the SRL robotics laboratory and is scheduled for installation at the 321-M fuel fabrication area. A mobile robot was employed by SRP for a radiation monitoring task at a waste tank top in H-Area. Several other robots are installed in the SRL robotics laboratories and application development programs are underway. The status of these applications is presented in this report
Efficiency of interaction between various radiation and chemicals

International Nuclear Information System (INIS)

Kim, Jin Kyu; Song, H. S.; Kim, J. S.; Chun, K. J.; Lee, Y. K.; Lee, B. H.; Shin, H. S.; Lee, K. H.; Petin, Vladislav G.

2002-01-01

KAERI and INP (Poland) have been carried out parallel study and joint experiments on the major topics according to MOU about their cooperative project. Major experimental techniques were TSH assay, comet assay, and synergism assay. The research consisted of the following workscopes. 1) Application of TSH bioindicator for studying the biological efficiency of radiation, 2) Relative biological efficiency of californium-252 neutrons in the induction of gene and lethal mutations in TSH cells normal and enriched with boron compound, 3) Effect of pesticide on radiation-induced mutations in TSH cells, 4) Interaction of radiation with pesticide on DNA damage in human peripheral blood lymphocytes, 5) Radiomodifying effect of boron and gadolinium compounds in human peripheral blood lymphocytes, 6) Mathematical description of synergistic interactions, 7) General regularities of synergistic interactions, and 8) Determinant of synergistic interaction between radiation, heat and chemicals in cell killing. Both institutes have established wide variety of research techniques applicable to various radiation research through the cooperation. The results of research can make the role of fundamental basis for the better relationship between Korea and Poland
Separation of Am-Cm from Al(NO3)3 waste solutions by in-canyon-tank precipitation as oxalates

International Nuclear Information System (INIS)

Gray, L.W.; Burney, G.A.; Wilson, T.W.; McKibben, J.M.; Bibler, N.E.; Holtzscheiter, E.W.; Campbell, T.G.

1982-04-01

A process for recovery of Am-Cm residues from high-activity waste concentrates has been developed specifically for application in Savannah River Plant (SRP) canyon tanks. The Am-Cm residues were collected from a campaign to produce plutonium containing high isotopic concentrations of 242 Pu. The separation of Am-Cm from the high-activity waste stream, containing about 2M Al(NO 3 ) 3 , is necessary to produce an acceptable feed solution for a later pressurized cation exchange chromatography separation and purification step. The new process includes formic acid denitration, adjustment of contaminating cations by evaporation and water dilution, and oxalate precipitation of the actinides and lanthanides. After washing, the precipitate was dissolved in 8M nitric acid and the oxalate was destroyed by nitric acid oxidation that was catalyzed by manganous ions. This new process generates about one-fourth the waste of the californium solvent extraction process, which it replaced. The new process also produces a cleaner feed solution for the pressurized cation exchange chromatography separation and purification step
Fabrication of intense neutron sources for medical applications

International Nuclear Information System (INIS)

Boulogne, A.R.; Walker, V.W.

1975-01-01

Simulated sources containing 252 Cf equivalents of 0.1 to 1.0 milligrams were prepared. Samarium was used as the simulant in a modified chemical plating technique similar to that used to prepare palladium-californium oxide cermet for industrial applications. The length of the platinum-10 percent iridium doubly encapsulated source with its protective sheath is 0.545 in. (14.1 mm). Outside dia of the source, including its sheath, is 0.109 in. (2.8 mm). Existing ''Brachytrons'' can accommodate this source form. This capsule system will withstand internal gas pressures from helium due to alpha decay and fission gases from a 1 mg 252 Cf source after ten years if the source is subjected to a maximum temperature of 800 0 C, the theoretical temperature of an accidental fire. Under these conditions the safety factor is 3. The capsule system is being tested with tracer amounts of 252 Cf to ensure that it will withstand adverse service conditions as well as tests specified for Special Form Materials. (auth)
4π-spectrometer technique for measurements of secondary neutron average number in nuclear fission by 252Cf neutrons

International Nuclear Information System (INIS)

Vasil'ev, Yu.A.; Barashkov, Yu.A.; Golovanov, O.A.; Sidorov, L.V.

1977-01-01

A method for determining the average number of secondary neutrons anti ν produced in nuclear fission by the neutrons of the 252 Cf fission spectra by means of a 4π time-of-flight spectrometer is described. Layers of 252 Cf and an isotope studied are placed close to each other; if the isotope layer density is 1 mg/cm 2 probability of its fission is about 10 -5 per one spontaneous fission of californium. Fission fragments of 252 Cf and the isotope investigated have been detected by two surface-barrier counters with an efficiency close to 100%. The layers and the counters are situated in a measuring chamber placed in the center of the 4π time-of-flight spectrometer. The latter is utilized as a neutron counter because of its fast response. The method has been verified by carrying out measurements for 235 U and 239 Pu. A comparison of the experimental and calculated results shows that the method suggested can apply to determine the number of secondary neutrons in fission of isotopes that have not been investigated yet
B(E2) ↑ (01+ -> 21+) predictions for even–even nuclei in the differential equation model

International Nuclear Information System (INIS)

Nayak, R.C.; Pattnaik, S.

2015-01-01

We use the recently developed differential equation model (DEM) for the reduced electric quadrupole transition probability B(E2)↑ for the transition from the ground to the first 2 + state for predicting its values for a wide range of even–even nuclides almost throughout the nuclear landscape from Neon to Californium. This is made possible as the principal equation in the model, namely, the differential equation connecting the B(E2)↑ value of a given even–even nucleus with its derivatives with respect to the neutron and proton numbers, provides two different recursion relations, each connecting three different neighboring even–even nuclei from lower- to higher-mass numbers and vice versa. These relations are primarily responsible in extrapolating from known to unknown terrain of the B(E2)↑-landscape and thereby facilitate the predictions throughout. As a result, we have succeeded in predicting its hitherto unknown value for the adjacent 251 isotopes lying on either side of the known B(E2)↑ database. (author)

Reprocessing of nuclear fuels at the Savannah River Plant

International Nuclear Information System (INIS)

Gray, L.W.

1986-01-01

For more than 30 years, the Savannah River Plant (SRP) has been a major supplier of nuclear materials such as plutonium-239 and tritium-3 for nuclear and thermonuclear weapons, plutonium-238 for space exploration, and isotopes of americium, curium, and californium for use in the nuclear research community. SRP is a complete nuclear park, providing most of the processes in the nuclear fuel cycle. Key processes involve fabrication and cladding of the nuclear fuel, target, and control assemblies; rework of heavy water for use as reactor moderator; reactor loading, operation, and unloading; chemical recovery of the reactor transmutation products and spent fuels; and management of the gaseous, liquid, and solid nuclear and chemical wastes; plus a host of support operations. The site's history and the key processes from fabrication of reactor fuels and targets to finishing of virgin plutonium for use in the nuclear weapons complex are reviewed. Emphasis has been given to the chemistry of the recovery and purification of weapons grade plutonium from irradiated reactor targets
Test and evaluation of infrared detectors and arrays; Proceedings of the Meeting, Orlando, FL, Mar. 27-29, 1989

Science.gov (United States)

Hoke, Forney M.

Papers on the testing and evaluation of IR detectors and arrays are presented, covering topics such as a short wavelength IR test system, pulse height analysis, the use of an expert system for IR detector testing, low-background IR focal plane testing, electron beam testing, high performance silicide Schottky photodiodes, the SDI organization focal plane test program, the absorption cross section of arsenic in silicon, and long wavelength IR hybrids. Other topics include low background radiometric detector measurements, an ultralow background dewar for IR detector characterization studies, a computer assisted mosaic array test station, a configurable detector array test station, automated detector material characterization capabilities, and a test system for mercury cadmium telluride photoconductor arrays. Additional topics include ionization dosimetry measurements inside a dewar for linac electron and californium-252 neutron environments, a radiation test facility using a variable-flux electron beam source, automated visual inspection of IR focal plane arrays, a titanium cryostat for low temperature radiation effects studies, a low dose rate gamma test facility, and the test and evaluation of stability in IR staring focal plane arrays after nonuniformity correction.
Dust vortices, clouds, and jets in nuclear-induced plasmas

International Nuclear Information System (INIS)

Vladimirov, V.I.; Deputatova, L.V.; Nefedov, A.P.; Fortov, V.E.; Rykov, V.A.; Khudyakov, A.V.

2001-01-01

The collective movement of dust particles in a plasma formed during deceleration of decay products of californium nuclei in neon is investigated experimentally. For the first time, compact vortex structures containing a large number of coagulating dust particles and dense dust clouds evolving in time are observed. Dust formations have clearly defined boundaries and particles in them form ordered liquid-type structures. Under steady-state conditions, dust structures exist from several minutes to hours. An increase in the voltage applied to the high-voltage electrode leads to the formation of dust particle jets. A change in the electric field configuration transforms the structures from one type to another. A strong recombination of electrons and ions at dust particles is observed. The momentum transfer from ions drifting in an external field to gas molecules is studied using the Monte Carlo method. It is shown that the transferred momentum is so large that it may cause a gas flow. The characteristic features of vortex flow in neon and in air are explained
Glasses impregnated with lead for radiation shielding

International Nuclear Information System (INIS)

Abd El Monem, A.M.; Kansouh, W.A.; Megahid, R.M.; Ismail, A.L.; Awad, E.M.

2005-01-01

The attenuation properties of glasses with different concentration of lead have been investigated for the attenuation of gamma-rays from cesium-137 and for total gamma rays using a beam of neutrons and gamma rays emitted from californium-252 source. Measurements have been performed using a gamma-ray spectrometer with Nal(T1) detector for gamma-rays emitted from 137 Cs and a neutron/gamma spectrometer with stilbene scintillator for measurement of total gamma-rays from 252 Cf neutron source. The latter applied the pulse shape discrimination technique to distinguish between recoil proton and recoil electron pulses. The obtained results given the form displayed pulse height spectra and attenuation relations which were used to derive the linear attenuation coefficient (μ), and the mass attenuation coefficient (mu/p) of the investigated glasses. In addition, calculations were performed to determine the attenuation properties of glass shields under investigation using XCOM code given by the others. A comparison of the shielding properties of these glasses with some standard shielding materials indicated that, the investigated glasses process the shielding advantages required for different nuclear technology applications
Calibration techniques and results for the Portsmouth Cf shuffler

International Nuclear Information System (INIS)

Gross, J.C.; Wines, K.M.

1993-01-01

As environmental concerns over radioactive waste disposal continue to rise, the importance of Californium shufflers as a versatile waste monitoring and segregation instrument also continue to increase. The extent to which different amounts and types of materials can be measured by the shuffler is directly related to the extent of its calibration. As shufflers become more common place and their waste management uses also rise, the importance of a wide ranging and thorough calibration becomes critical. This paper presents the techniques used at the Portsmouth Gaseous Diffusion Plant for calibrating the shuffler to detect levels of U-235 in radioactive waste. While the calibration techniques are similar to those used by Los Alamos, the standards that were used were constructed somewhat differently so that geometric effects are maximized. Also presented are shuffler transmission measurements that are used to determine the matrix type and the corresponding calibration. A discussion of the calibration data is given. This discussion includes specific aspects of the calibration such as overall range, high end limits, and poly shielding range and usefulness
Genetic exchanges caused by ultraviolet photoproducts in phage lamda DNA molecules: the role of DNA replication

International Nuclear Information System (INIS)

Lin, P.F.; Howard-Flanders, P.; Yale Univ., New Haven, Conn.

1976-01-01

Genetic recombination induced by structural damage in DNA molecules was investigated in E. coli K12(lamda) lysogens infected with genetically marked phage lamda. Photoproducts were induced in the phage DNA before infection by exposing them either to 313 nm light in the presence of acetophenone or to 254 nm light. To test the role of the replication of the damage phage DNA on the frequency of the induced recombination , both heteroimmune and homoimmune crosses were performed, and scored for P + recombinants. In heteroimmune crosses, recombination was less frequent in infected cells exposed to visible light and in wild type cells able to perform excision repair than in excision-defective lysogens. Therefore, much of the induced recombination can be attributed to the pyrimidine dimers in the phage DNA. In homoimmune crosses, replication of the phage DNA containing ultraviolet photoproducts was represented by lamda immunity, and was further blocked by the lack of the P gene product needed for replication. The 254 nm photoproducts increased the frequency of recombination in these homoimmune crosses, even though phage DNA replication was blocked. Irradiation with 313 nm light and acetophenone M, which produces dimers and unknown photoproducts, was not as effective per dimer as the 254 nm light. It is concluded from these results that certain unidentified 254 nm photoproducts can cause recombination even in the absence of DNA replication. They are not pyrimidine dimers, as they are not susceptible to excision repair or photoreactivation. In contrast, pyrimidine dimers appear to cause recombination only when the DNA containing them undergoes replication. (orig./MG) [de
Regional Groundwater and Storms Are Hydrologic Controls on the Quality and Export of Dissolved Organic Matter in Two Tropical Rainforest Streams, Costa Rica

Science.gov (United States)

Osburn, Christopher L.; Oviedo-Vargas, Diana; Barnett, Emily; Dierick, Diego; Oberbauer, Steven F.; Genereux, David P.

2018-03-01

A paired-watershed approach was used to compare the quality and fluxes of dissolved organic matter (DOM) during stormflow and baseflow in two lowland tropical rainforest streams located in northeastern Costa Rica. The Arboleda stream received regional groundwater (RGW) flow, whereas the Taconazo stream did not. DOM quality was assessed with absorbance and fluorescence and stable carbon isotope (δ13C-DOC) values. RGW DOM lacked detectable fluorescence and had specific ultraviolet absorption (SUVA254) and absorbance slope ratio (SR) values consistent with low aromaticity and low molecular weight material, respectively. We attributed these properties to microbial degradation and sorption of humic DOM to mineral surfaces during transport through bedrock. SUVA254 values were lower and SR values were higher in the Arboleda stream during baseflow compared to the Taconazo stream, presumably due to dilution by RGW. However, no significant difference in SUVA254 or SR occurred between the streams during stormflow. SUVA254 was negatively correlated to δ13C-DOC (r2 = 0.61, P runoff containing soil and throughfall C sources. Mean DOC export from the Taconazo stream during the study period was 2.62 ± 0.39 g C m-2 year-1, consistent with other tropical streams, yet mean DOC export from the Arboleda stream was 13.79 ± 2.07 g C m-2 year-1, one of the highest exports reported and demonstrating a substantial impact of old RGW from outside the watershed boundary can have on surface water carbon cycling.
Positron annihilation studies of icosahedral quasicrystals and their approximants in the Al-Cu-Ru-(Si) alloy systems

International Nuclear Information System (INIS)

Uchiyama, H; Takahashi, T; Arinuma, K; Sato, K; Kanazawa, I; Hamada, E; Suzuki, T; Kirihara, K; Kimura, K

2004-01-01

The positron lifetimes for the icosahedral quasicrystal Al 62.4 Cu 25.4 Ru 12.2 and its cubic approximants (1/ 1-Al 58 Cu 31.5 Ru 10.5 , 1/ 1-Al 68 Cu 7 Ru 17 Si 8 , and 1/0-Al 55 Cu 15 Ru 20 Si 10 ), two-detector coincident Doppler broadening for the icosahedral quasicrystal Al 62.4 Cu 25.4 Ru 12.2 and its 1/ 1-Al 68 Cu 7 Ru 17 Si 8 cubic approximant, and the Doppler broadening obtained by making use of a slow positron beam for the 1/ 1-Al 58 Cu 31.5 Ru 10.5 cubic approximant have been measured. Structurally intrinsic trapping sites giving rise to saturation trapping were detected by lifetime measurements. The chemical environments of the trapping sites in the icosahedral quasicrystal Al 62.4 Cu 25.4 Ru 12.2 and the 1/ 1-Al 68 Cu 7 Ru 17 Si 8 cubic approximant were determined by coincident Doppler broadening techniques to be dominantly surrounded by Al atoms. The positron diffusion length in the 1/ 1-Al 58 Cu 31.5 Ru 10.5 cubic approximant derived from the measured S parameter measured by means of a slow positron beam was ∼ 180 A, which is clearly too short, probably due to the high concentration of trapping sites as described above. The atomic structures of the icosahedral quasicrystal Al 62.4 Cu 25.4 Ru 12.2 and its variety of approximants are discussed and compared to the present proposed model
ORF Alignment: NT_033777 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available Query: 134 SDCHELDEGVRVDGVYRFLVPERNEVQRDLYERYCAFATDGPAWTVIQSRGGSFDPHENF 193 ... SDCHELDEGVRVDGVYRFLVP...ERNEVQRDLYERYCAFATDGPAWTVIQSRGGSFDPHENF Sbjct: 1 ... SDCHELDEGVRVDGVYRFLVPERNEVQRDL...YERYCAFATDGPAWTVIQSRGGSFDPHENF 60 ... Query: 254 SYNYQLSVAGEFRGSLPDALEQHNRMDFSTYDRRRNHAKSADSTCGEDYGGGWWFDRCTQ 3
ORF Alignment: NC_000921 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NLVVLQELNPYSYFCQSENPKFFDLGEYFEEDKAFFS 60 ... Query: 134 DLGFEPIATSVGKLGLMVCWDQWYPEAARIMALKGAEILIYPSAIGFLEEDSNEE...KKRQQ 193 ... DLGFEPIATSVGKLGLMVCWDQWYPEAARIMALKGAEILIYPSAIGFLEEDSNEEKKRQQ... Sbjct: 121 DLGFEPIATSVGKLGLMVCWDQWYPEAARIMALKGAEILIYPSAIGFLEEDSNEEKKRQQ 180 ... Query: 254 EEILYAEIELERTEEVRRM
The pin pixel detector--X-ray imaging

CERN Document Server

Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Simmons, J E; Stephenson, R

2002-01-01

The development and testing of a soft X-ray gas pixel detector, which uses connector pins for the anodes is reported. Based on a commercial 100 pin connector block, a prototype detector of aperture 25.4 mm centre dot 25.4 mm can be economically fabricated. The individual pin anodes all show the expected characteristics of small gas detectors capable of counting rates reaching 1 MHz per pin. A 2-dimensional resistive divide readout system has been developed to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics.
Bacterial growth in humic waters exposed to UV-radiation and simulated sunlight

DEFF Research Database (Denmark)

Corin, N.; Backlund, P.; Wiklund, T.

1998-01-01

Sterile filtered (0.45 mu m) humic lake water was exposed to simulated sunlight (300-800 nm) or W-radiation (254 run)for various periods of times and the dissolved organic carbon content, absorbance at 254 and 460 nm and PH were recorded. The irradiated water was inoculated with a natural bacterial...... assemblage and the number of viable bacteria war estimated 3 and 5 days after the inoculation using the plate count technique. The number of viable bacteria increased with the irradiation time indicating that the chemical changes of the humus macromolecules observed during irradiation resulted...
In situ x-ray fluorescence and californium-252 neutron activation analysis for marine and terrestrial mineral exploration

International Nuclear Information System (INIS)

Wogman, N.A.

1976-12-01

Instrumentation has been designed for in situ analysis of marine and terrestrial minerals using the techniques of x-ray fluorescence and neutron activation analysis. The energy-dispersive x-ray fluorescence analyzer allows more than 20 elements to be quantitatively measured at the 10 ppM level in water depths to 300 m. The analyzer consists of a solid cryogen-cooled Si(Li) detector, a 50 mCi 109 Cd or 57 Co excitation source, and an analyzer-computer system for data storage and manipulation. The neutron activation analysis, which is designed to measure up to 30 elements at parts per hundred to ppM levels, utilizes the man-made element 252 Cf as its neutron activation source. The resulting radioelements which emit characteristic gamma radiation are then analyzed in situ during 2- to 200-s counting intervals with Ge(Li) or NaI(T1) detector systems. An extension of this latter technique, which uses a 252 Cf- 235 U fueled subcritical multiplier, is also being studied. The subcritical facility allows the neutrons from the 252 Cf source to be multiplied, thus providing greater neutron flux. Details of these in situ analysis systems, actual in situ spectra, and recorded data are discussed with respect to the detection of minerals at their varying concentration levels. The system response of each illustrates its usefulness for various rapid environmental mineral exploration studies. These techniques can be utilized on terrestrial surfaces and marine or fresh water sediments. 5 figures, 2 tables
ORF Alignment: NC_005296 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... palustris CGA009] ... Length = 77 ... Query: 195 NRRKVYPESARQTRQQGTASLSFAIGASGEVISYKITRSTGSDALDRAIDS...MMKTARPPP 254 ... NRRKVYPESARQTRQQGTASLSFAIGASGEVISYKITRSTGSDALDRAIDSMMKTA...RPPP Sbjct: 1 ... NRRKVYPESARQTRQQGTASLSFAIGASGEVISYKITRSTGSDALDRAIDSMMKTARPPP 60 ...
Hurricane Matthew's Effects on Wetland Sources of Organic Matter to North Carolina Coastal Waters.

Science.gov (United States)

Rudolph, J. C.; Osburn, C. L.; Paerl, H. W.; Hounshell, A.

2017-12-01

Increased frequency and intensity of storm events such as tropical cyclones will have a major impact on estuarine and coastal biogeochemical cycling. Here, we determined the sources of dissolved and particulate organic matter (DOM and POM) as part of a larger study to quantify the short-term (several months) response of carbon and nitrogen cycling in the Neuse River Estuary-Pamlico Sound (NRE-PS) ecosystem to floodwaters associated with Hurricane Matthew. Sampling was conducted weekly in both the NRE-PS (October 2016 to January 2017), the Neuse River (NR) (October to December 2016) and in freshwater wetlands of the Neuse River above head of tide in March 2017. Specific ultraviolet (UV) absorbance at 254 nm (SUVA254) and stable carbon isotope ratios (δ13C-DOC) were used to determine the sources of DOM and POM transported to the NRE-PS in post-hurricane floodwaters. For DOM, SUVA254 values increased from 3.23 ±0.52 mg C L-1 m-1 in the NR to 4.14±0.52 mg C L-1 m-1 in the NRE and then declined to 3.63±0.32 mg C L-1 m-1 in PS. Combined with depleted δ13C-DOC values (-26 to -32‰) and elevated C:N values in the estuary and sound, these results confirm continued loading of fresh terrestrial organic matter into NRE-PS weeks after the storm. For POM, δ13C-POC and C:N ratio results likewise indicated a terrestrial source in floodwaters. SUVA254 values >3.5 mg C L-1 m-1 coupled with the depleted δ13C values and large C:N values were consistent with DOM primarily sourced from wetlands (e.g., wetland SUVA254 = 3.77±0.52 mg C L-1 m-1 in March 2017). We hypothesize that floodwaters connected riverine wetlands to the main channel of the NR, exporting DOM and POM into the NRE-PS. Our results indicate that upstream wetlands play a central and potentially significant role in organic matter enrichment and metabolism of estuarine and coastal waters, in light of increasing frequencies and intensities of tropical cyclones impacting coastal watersheds.
Mutagenesis and cytotoxicity in human epithelial cells by far- and near-ultraviolet radiations: action spectra

International Nuclear Information System (INIS)

Jones, C.A.; Huberman, E.; Cunningham, M.L.; Peak, M.J.

1987-01-01

Action spectra were determined for cell killing and mutation by monochromatic ultraviolet and visible radiations (254-434 nm) in cultured human epithelial P3 cells. Cell killing was more efficient following radiation at the shorter wavelengths (254-434 nm) than at longer wavelengths (365-434 nm). At 254 nm, for example, a fluence of 11 Jm-2 gave 37% cell survival, while at 365 nm, 17 X 10(5) Jm-2 gave equivalent survival. At 434 nm little killing was observed with fluences up to 3 X 10(6) Jm-2. Mutant induction, determined at the hypoxanthine-guanine phosphoribosyltransferase locus, was caused by radiation at 254, 313, and 365 nm. There was no mutant induction at 334 nm although this wavelength was highly cytotoxic. Mutagenesis was not induced by 434 nm radiation, either. There was a weak response at 405 nm; the mutant frequencies were only slightly increased above background levels. For the mutagenic wavelengths, log-log plots of the mutation frequency against fluence showed linear regressions with positive slopes of 2.5, consistent with data from a previous study using Escherichia coli. The data points of the action spectra for lethality and mutagenesis were similar to the spectrum for DNA damage at wavelengths shorter than 313 nm, whereas at longer wavelengths the lethality spectrum had a shoulder, and the mutagenesis spectrum had a secondary peak at 365 nm. No correlation was observed for the P3 cells between the spectra for cell killing and mutagenesis caused by wavelengths longer than 313 nm and the induction of DNA breakage or the formation of DNA-to-protein covalent bonds in these cells
Using dissolved organic matter age and composition to detect permafrost thaw in boreal watersheds of interior Alaska

Science.gov (United States)

O'Donnell, Jonathan A.; Aiken, George R.; Walvoord, Michelle A.; Raymond, Peter A.; Butler, Kenna D.; Dornblaser, Mark M.; Heckman, Katherine

2014-11-01

Recent warming at high latitudes has accelerated permafrost thaw, which can modify soil carbon dynamics and watershed hydrology. The flux and composition of dissolved organic matter (DOM) from soils to rivers are sensitive to permafrost configuration and its impact on subsurface hydrology and groundwater discharge. Here, we evaluate the utility of DOM composition and age as a tool for detecting permafrost thaw in three rivers (Beaver, Birch, and Hess Creeks) within the discontinuous permafrost zone of interior Alaska. We observed strong temporal controls on Δ14C content of hydrophobic acid isolates (Δ14C-HPOA) across all rivers, with the most enriched values occurring during spring snowmelt (75 ± 8‰) and most depleted during winter flow (-21 ± 8‰). Radiocarbon ages of winter flow samples ranged from 35 to 445 yr BP, closely tracking estimated median base flow travel times for this region (335 years). During spring snowmelt, young DOM was composed of highly aromatic, high molecular-weight compounds, whereas older DOM of winter flow had lower aromaticity and molecular weight. We observed a significant correlation between Δ14C-HPOA and UV absorbance coefficient at 254 nm (α254) across all study rivers. Using α254 as an optical indicator for Δ14C-HPOA, we also observed a long-term decline in α254 during maximum annual thaw depth over the last decade at the Hess Creek study site. These findings suggest a shift in watershed hydrology associated with increasing active layer thickness. Further development of DOM optical indicators may serve as a novel and inexpensive tool for detecting permafrost degradation in northern watersheds.
Tracking ultrasonically structural changes of natural aquatic organic carbon: Chemical fractionation and spectroscopic approaches.

Science.gov (United States)

Al-Juboori, Raed A; Yusaf, Talal; Aravinthan, Vasantha; Bowtell, Leslie

2016-02-01

In this study, the structural alteration to DOC for a range of ultrasound treatments was investigated with chemical fractionation and UV-vis spectroscopic measurement. Ultrasound treatments were applied in continuous and pulsed modes at power levels of 48 and 84 W for effective treatment times of 5 and 15 min. Overall results show that the ultrasound treatments tended to degrade the hydrophobic aromatic fraction, while increasing the hydrophilic fraction to a lesser extent. The highest recorded reduction of hydrophobic DOC (17.8%) was achieved with pulse treatment of 84 W for15 min, while the highest increase in the hydrophilic DOC (10.5%) was obtained with continuous treatment at 84 W and 5 min. The optimal ultrasound treatment conditions were found to be pulse mode at high power and short treatment time, causing a minimal increase in the hydrophilic fraction of 1.3% with moderate removal of the hydrophobic fraction of 15.52%. The same treatment conditions, with longer treatment time, resulted in the highest removal of SUVA254 and SUVA280 of 17.09% and 16.93, respectively. These results indicate the potential for ultrasound treatments in DOC structural alteration. The hydrophobic fraction showed strong and significant correlations with UV absorbance at 254 and 280 nm. A254/A204 also exhibited strong and significant correlations with the hydrophobic/hydrophilic ratio. The other UV ratios (A250/A365 (E2/E3) and A254/A436) had weak and insignificant correlations with the hydrophobic/hydrophilic ratio. This confirms the applicability of UV indices as a suitable surrogate method for estimating the hydrophobic/hydrophilic structure. Copyright © 2015 Elsevier Ltd. All rights reserved.
Treatment of high strength distillery wastewater (cherry stillage) by integrated aerobic biological oxidation and ozonation.

Science.gov (United States)

Beltrán, F J; Alvarez, P M; Rodríguez, E M; García-Araya, J F; Rivas, J

2001-01-01

The performance of integrated aerobic digestion and ozonation for the treatment of high strength distillery wastewater (i.e., cherry stillage) is reported. Experiments were conducted in laboratory batch systems operating in draw and fill mode. For the biological step, activated sludge from a municipal wastewater treatment facility was used as inoculum, showing a high degree of activity to distillery wastewater. Thus, BOD and COD overall conversions of 95% and 82% were achieved, respectively. However, polyphenol content and absorbance at 254 nm (A(254)) could not be reduced more than 35% and 15%, respectively, by means of single biological oxidation. By considering COD as substrate, the aerobic digestion process followed a Contois' model kinetics, from which the maximum specific growth rate of microorganisms (mu(max)) and the inhibition factor, beta, were then evaluated at different conditions of temperature and pH. In the combined process, the effect of a post-ozonation stage was studied. The main goals achieved by the ozonation step were the removal of polyphenols and A(254). Therefore, ozonation was shown to be an appropriate technology to aid aerobic biological oxidation in the treatment of cherry stillage.
Comparative analysis of upper gastrointestinal endoscopy, double-contrast upper gastrointestinal barium X-ray radiography, and the titer of serum anti-Helicobacter pylori IgG focusing on the diagnosis of atrophic gastritis.

Science.gov (United States)

Yamamichi, Nobutake; Hirano, Chigaya; Takahashi, Yu; Minatsuki, Chihiro; Nakayama, Chiemi; Matsuda, Rie; Shimamoto, Takeshi; Takeuchi, Chihiro; Kodashima, Shinya; Ono, Satoshi; Tsuji, Yosuke; Fujishiro, Mitsuhiro; Wada, Ryoichi; Mitsushima, Toru; Koike, Kazuhiko

2016-04-01

Upper gastrointestinal endoscopy (UGI-ES) and double-contrast upper gastrointestinal barium X-ray radiography (UGI-XR) are two major image-based methods to diagnose atrophic gastritis, which is mostly induced by Helicobacter pylori infection. However, there have been few studies directly comparing them. Atrophic gastritis was evaluated using the data of 962 healthy subjects who underwent UGI-ES and UGI-XR within 1 year. Based on UGI-ES and UGI-XR, 602 subjects did not have atrophic gastritis and 254 subjects did have it. Considering UGI-ES-based atrophic gastritis as the standard, sensitivity and specificity of UGI-XR-based atrophic gastritis were 92.0 % (254/276) and 92.8 % (602/649), respectively. The seven-grade Kimura-Takemoto classification of UGI-ES-based atrophic gastritis showed a strong and significant association with the four-grade UGI-XR-based atrophic gastritis. Sensitivity and specificity of serum anti-Helicobacter pylori IgG to detect UGI-ES/UGI-XR-based atrophic gastritis were 89.4 % (227/254) and 99.8 % (601/602), indicating that atrophic gastritis can be overlooked according to serum anti-Helicobacter pylori IgG alone.

Accelerating the discovery of hidden two-dimensional magnets using machine learning and first principle calculations

Science.gov (United States)

Miyazato, Itsuki; Tanaka, Yuzuru; Takahashi, Keisuke

2018-02-01

Two-dimensional (2D) magnets are explored in terms of data science and first principle calculations. Machine learning determines four descriptors for predicting the magnetic moments of 2D materials within reported 216 2D materials data. With the trained machine, 254 2D materials are predicted to have high magnetic moments. First principle calculations are performed to evaluate the predicted 254 2D materials where eight undiscovered stable 2D materials with high magnetic moments are revealed. The approach taken in this work indicates that undiscovered materials can be surfaced by utilizing data science and materials data, leading to an innovative way of discovering hidden materials.
Mycological studies housed in the Apollo 16 microbial ecology evaluation device

Science.gov (United States)

Volz, P. A.

1973-01-01

Survival, death, and phenotype count have yielded variation in the number of fungi recovered from the controls and the flight exposed cuvettes during preliminary analysis of postflight first phase data. Also the preliminary analysis was indicative that fungi exposed to specific space flight conditions demonstrated variable survival rates and phenotype counts. Specific space flight conditions included full light space exposure for Chaetomium globosum, exposure at 300- and 254-nanometer wavelengths for Rhodotorula rubra, full light and 280-nanometer wavelength exposure for Trichophyton terrestre, and 254-nanometer wavelength exposure for Saccharomyces cerevisiae. In general, phenotype counts for flight cuvettes and survival rates for control cuvettes were higher compared with the remaining cuvettes.
Four channel Cosmic Ray detector based on polymaq

Science.gov (United States)

Herrera-Guzman, K. N.; Gutierrez-Sanchez, R. A.; Felix, J.

2017-01-01

The Cherenkov radiation has been widely studied in transparent materials, and applied to detect and identify elementary particles. But it has not been widely studied in opaque materials. A four channels radiation detector has been designed, built, characterized, and operated; based on four polymaq (UHMW-PE) bars of 2.54 cm X 5.08 cm X 25.4 cm, which is an opaque material to visible radiation to the human eye. Silicon photo detectors, Hamamatsu, avalanche type (APD) are used to detect the radiation produced by the passage of particles in the detector blocks. The design, construction, characterization, operation, and preliminary results of this cosmic ray detector details are presented.
ORF Alignment: NT_037436 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... gb|AAM10986.1| AT04143p [Drosophila melanogaster] ... Length = 254 ... Query: 12 ... STALRLLGANVEL...FGVLTRNPTYRMILDDLEQRGIDISHCTFTDASPPFSTIVQDRWTRR 71 ... STALRLLGANVELFGVLT...RNPTYRMILDDLEQRGIDISHCTFTDASPPFSTIVQDRWTRR Sbjct: 1 ... STALRLLGANVELFGVLTRNPTYRMILDDLEQRGIDISHCTFTDASPPFSTIVQ
S. Afr. J. Anim. Sci. I I , 247- 254 ( I 981 ) PRACTICAL ...

African Journals Online (AJOL)

In the case of sheep the treatment of OF-collected samples (total extrusa vs. solid frac- tion) had a significant ... of laboratory drying equipment, is discussed. Oesophageally ..... Chemistry of browning reactions in model system. J. Agric. Food ...
SSC 254 Screen-Based Word Processors: Production Tests. The Lanier Word Processor.

Science.gov (United States)

Moyer, Ruth A.

Designed for use in Trident Technical College's Secretarial Lab, this series of 12 production tests focuses on the use of the Lanier Word Processor for a variety of tasks. In tests 1 and 2, students are required to type and print out letters. Tests 3 through 8 require students to reformat a text; make corrections on a letter; divide and combine…
50 CFR 14.254 - What are the requirements contained in these regulations?

Science.gov (United States)

2010-10-01

... IMPORTATION OF WILDLIFE AND PLANTS IMPORTATION, EXPORTATION, AND TRANSPORTATION OF WILDLIFE Captive Wildlife... exemption in § 14.255, an accredited wildlife sanctuary must maintain complete and accurate records of any..., sold, or otherwise transferred; and the dates of these transactions. The accredited wildlife sanctuary...
Adsorption and photocatalytic oxidation of formaldehyde on a clay-TiO{sub 2} composite

Energy Technology Data Exchange (ETDEWEB)

Kibanova, Daria [Facultad de Quimica, Universidad Nacional Autonoma de Mexico (Mexico); Departamento de Procesos y Tecnologia, Universidad Autonoma Metropolitana (Mexico); Sleiman, Mohamad [Lawrence Berkeley National Laboratory, Indoor Environment Group, Environmental Energy Technologies Division (United States); Cervini-Silva, Javiera, E-mail: jcervini@correo.cua.uam.mx [Departamento de Procesos y Tecnologia, Universidad Autonoma Metropolitana (Mexico); NASA Astrobiology Institute (United States); Destaillats, Hugo, E-mail: HDestaillats@lbl.gov [Lawrence Berkeley National Laboratory, Indoor Environment Group, Environmental Energy Technologies Division (United States); Arizona State University, Department of Chemistry and Biochemistry (United States)

2012-04-15

Highlights: Black-Right-Pointing-Pointer Formaldehyde adsorption and photocatalytic elimination on hectorite-TiO{sub 2} nanocomposites. Black-Right-Pointing-Pointer Dark adsorption in dry air >4 times higher than P25 (reference). Black-Right-Pointing-Pointer Dark adsorption in humid air dominated by adsorbed water layer. Black-Right-Pointing-Pointer Photocatalytic removal efficiency proportional to the Ti content, increased with contact time. Black-Right-Pointing-Pointer More complete elimination with 254 + 185 nm irradiation. - Abstract: We investigated the adsorption capacity and photocatalytic removal efficiency of formaldehyde using a hectorite-TiO{sub 2} composite in a bench flow reactor. The same experimental conditions were applied to pure TiO{sub 2} (Degussa P25) as a reference. The catalysts were irradiated with either a UVA lamp (365 nm) or with one of two UVC lamps of 254 nm and 254 + 185 nm, respectively. Formaldehyde was introduced upstream at concentrations of 100-500 ppb, with relative humidity (RH) in the range 0-66% and residence times between 50 and 500 ms. Under dry air and without illumination, saturation of catalyst surfaces was achieved after {approx}200 min for P25 and {approx}1000 min for hectorite-TiO{sub 2}. The formaldehyde uptake capacity by hectorite-TiO{sub 2} was 4.1 times higher than that of P25, almost twice the BET surface area ratio. In the presence of humidity, the difference in uptake efficiency between both materials disappeared, and saturation was achieved faster (after {approx}200 min at 10% RH and {approx}60 min at 65% RH). Under irradiation with each of the three UV sources, removal efficiencies were proportional to the Ti content and increased with contact time. The removal efficiency decreased at high RH. A more complete elimination of formaldehyde was observed with the 254 + 185 nm UV source.
PELOLOSAN IKAN KURISI (Nemipterus japonicus MELALUI JUVENILE AND TRASH EXLUDER DEVICES PADA JARING ARAD

Directory of Open Access Journals (Sweden)

Hufiadi Hufiadi

2016-06-01

Full Text Available Permasalahan utama pada perikanan jaring arad adalah banyaknya jumlah hasil tangkap sampingan berukuran kecil yang belum layak tangkap. Dalam upaya untuk mengurangi tangkapan ikan muda yang belum layak tangkap telah dilakukan observasi dan ujicoba operasi penangkapan melalui penggunaan perangkat juvenile and trash exluder devices pada alat tangkap jaring arad yang dioperasikan nelayan di Pekalongan. Perangkat juvenile and trash exluder devices yang digunakan dibedakan pada ukuran jarak antar kisi, yaitu 10,0; 17,5; dan 25,4 mm. Analisis selektivitas kisi menggunakan model kurva logistik dengan bantuan solver pada Microsoft Excel. Hasil penelitian menunjukkan bahwa penggunaan juvenile and trash exluder devices pada jaring arad dapat meloloskan ikan kurisi (Nemipterus spp. berukuran kecil. Ukuran jarak antar kisi 25,4 mm mempunyai selektivitas yang paling baik terhadap ikan kurisi berdasarkan atas ukuran panjang baku dan jarak antar kisi 17,5 mm mempunyai selektivitas paling baik berdasarkan atas ukuran lingkar tubuh ikan kurisi. The serius problem on bottom mini trawl has the large number caught of bycatch caught especially for juvenile and trash fish. Improvement to reduce catches of juvenile was conducted through observation and experimental fishing using juvenile and trash exluder devices of mini bottom trawl in Pekalongan. The juvenile and trash excluder devices (juvenile and trash exluder devices in the experimental fishing with different space bar of the juvenile and trash exluder devices i.e. 10.0; 17.5; and 25.4 mm. The selectivity analysis of logistic curve by using solver on Microsoft Excel was applied. The results showed that juvenile and trash excluder devices might reduce catches of threadfin breams juvenile. Where as 25.4 space bar had the best selectivity based on the size of threadfin breams fork length and 17.5 mm space bar had the best selectivity based on the size of threadfin breams body girth.
Dissolved organic matter composition of winter flow in the Yukon River basin: Implications of permafrost thaw and increased groundwater discharge

Science.gov (United States)

O'Donnell, Jonathan A.; Aiken, George R.; Walvoord, Michelle Ann; Butler, Kenna D.

2012-01-01

Groundwater discharge to rivers has increased in recent decades across the circumpolar region and has been attributed to thawing permafrost in arctic and subarctic watersheds. Permafrost-driven changes in groundwater discharge will alter the flux of dissolved organic carbon (DOC) in rivers, yet little is known about the chemical composition and reactivity of dissolved organic matter (DOM) of groundwater in permafrost settings. Here, we characterize DOM composition of winter flow in 60 rivers and streams of the Yukon River basin to evaluate the biogeochemical consequences of enhanced groundwater discharge associated with permafrost thaw. DOC concentration of winter flow averaged 3.9 ± 0.5 mg C L−1, yet was highly variable across basins (ranging from 20 mg C L−1). In comparison to the summer-autumn period, DOM composition of winter flow had lower aromaticity (as indicated by specific ultraviolet absorbance at 254 nm, or SUVA254), lower hydrophobic acid content, and a higher proportion of hydrophilic compounds (HPI). Fluorescence spectroscopy and parallel factor analysis indicated enrichment of protein-like fluorophores in some, but not all, winter flow samples. The ratio of DOC to dissolved organic nitrogen, an indicator of DOM biodegradability, was positively correlated with SUVA254 and negatively correlated with the percentage of protein-like compounds. Using a simple two-pool mixing model, we evaluate possible changes in DOM during the summer-autumn period across a range of conditions reflecting possible increases in groundwater discharge. Across three watersheds, we consistently observed decreases in DOC concentration and SUVA254 and increases in HPI with increasing groundwater discharge. Spatial patterns in DOM composition of winter flow appear to reflect differences in the relative contributions of groundwater from suprapermafrost and subpermafrost aquifers across watersheds. Our findings call for more explicit consideration of DOC loss and stabilization
Two low-level gamma spectrometry systems of the IAEA Safeguards Analytical Laboratory

Energy Technology Data Exchange (ETDEWEB)

Parus, J L [IAEA, SAL, Vienna (Austria); Raab, W [IAEA, SAL, Vienna (Austria); Donohue, D [IAEA, SAL, Vienna (Austria); Jansta, V [IAEA, SAL, Vienna (Austria); Kierzek, J [IAEA, SAL, Vienna (Austria)

1997-03-01

A gamma spectrometry system designed for the measurement of samples with low and medium radioactivity (activity from a few to about 10{sup 4} Bq in the energy range from 25 to 2700 keV) has been installed at the IAEA Safeguards Analytical Laboratory in Seibersdorf. The system consists of 3 low level detectors: (1) n-type coaxial Ge with 42.4% relative efficiency, 1.85 keV FWHM at 1.33 MeV (2) planar Ge with 2000 mm{sup 2} area and 20 mm thickness, 562 eV FWHM at 122 keV (3) NaI(Tl) annulus of 25.4 cm diameter and 25.4 cm height, hole diameter 90 mm. (orig./DG)
Lon gene and photoprotection in Escherichia coli K-12

Energy Technology Data Exchange (ETDEWEB)

Waksman, G.; Thomas, G.; Favre, A. (Institut de Recherche en Biologie Moleculaire, Group de Photobiologie Moleculaire, Paris (France))

1984-03-01

Photoprotection, i.e. the increased resistance of the cells preilluminated with near ultraviolet light (300-380 nm) to the lethal action of 254nm radiations requires either an integrated prophage or a recA mutation in Escherichia coli K12 strains. Significant photoprotection occurs in an Escherichia coli K12 recA/sup +/ cell containing the lon allele responsible for filamentous growth after 254nm irradiation. The Fil phenotype can be suppressed by the sfiA or sfiB suppressor genes. Since the E. coli K12 recA/sup +/ lon sfiB strain exhibits no more photoprotection, it is concluded that in lon strains photoprotection is due to the abolition of the 254nm induced filamentation by the near ultraviolet treatment. In addition, near ultraviolet illumination of the cells leads to a severe restriction of the bulk protein synthesis. This effect is observed only in nuv/sup +/ cells that contain 4-thiouridine the chromophore responsible for photoprotection. It is proposed that in lon (lysogenic strains) photoprotection is due to prevention of the SOS response. During the growth lag, the low residual level of protein synthesis does not allow the induction of the SOS response and accordingly prevents filamentation (the lytic cycle).
The lon gene and photoprotection in Escherichia coli K-12

International Nuclear Information System (INIS)

Waksman, G.; Thomas, G.; Favre, A.

1984-01-01

Photoprotection, i.e. the increased resistance of the cells preilluminated with near ultraviolet light (300-380 nm) to the lethal action of 254nm radiations requires either an integrated prophage or a recA mutation in Escherichia coli K12 strains. Significant photoprotection occurs in an Escherichia coli K12 recA + cell containing the lon allele responsible for filamentous growth after 254nm irradiation. The Fil phenotype can be suppressed by the sfiA or sfiB suppressor genes. Since the E. coli K12 recA + lon sfiB strain exhibits no more photoprotection, it is concluded that in lon strains photoprotection is due to the abolition of the 254nm induced filamentation by the near ultraviolet treatment. In addition, near ultraviolet illumination of the cells leads to a severe restriction of the bulk protein synthesis. This effect is observed only in nuv + cells that contain 4-thiouridine the chromophore responsible for photoprotection. It is proposed that in lon (lysogenic strains) photoprotection is due to prevention of the SOS response. During the growth lag, the low residual level of protein synthesis does not allow the induction of the SOS response and accordingly prevents filamentation (the lytic cycle). (author)
Investigation of nitrogen transformations in a southern California constructed wastewater treatment wetland

Science.gov (United States)

Sartoris, J.J.; Thullen, J.S.; Barber, L.B.; Salas, D.E.

2000-01-01

A 9.9-ha combined habitat and wastewater treatment demonstration wetland was constructed and planted in the summer of 1994, at Eastern Municipal Water District’s (EMWD) Hemet/San Jacinto Regional Water Reclamation Facility (RWRF) in southern California. From January 1996 through September 1997, the marsh–pond–marsh wetland system was operated to polish an average of 3785 m3 d−1 (1×106 gal day−1) of secondary-treated effluent from the RWRF. Nitrogen removal was a major objective of this wetland treatment. Weekly inflow/outflow water quality monitoring of the wetland was supplemented with biannual, 45-station synoptic surveys within the system to determine internal distribution patterns of the nitrogen species (total ammonia, nitrite, nitrate, and organic nitrogen), total organic carbon (TOC), and ultraviolet absorbance at 254 nm (UV254). Synoptic surveys were carried out during May 22 and September 17, 1996, and May 6 and September 25, 1997 and the results were mapped using the ARC/INFO processing package and inverse distance weighted mathematical techniques. Distribution patterns of the various nitrogen species, TOC, and UV254 within the wetland indicate that the nitrogen dynamics of the system are influenced both by variations in treatment plant loading, and, increasingly, by the degree of coverage and maturity of the emergent vegetation.
The effects of photosensitizing antibiotics and ultraviolet irradiation on the biosynthesis of prostaglandins

International Nuclear Information System (INIS)

Lord, J.T.; Ziboh, V.A.; Blick, G.; Poitier, J.; Kursunoglu, I.; Penneys, N.S.

1978-01-01

Oxygenation of arachidonic acid in vitro by calf skin microsomal acetone powder was enhanced by UV-irradiation at wavelengths of 254 and 360 nm. Further enhancement of the oxygenation reaction was observed in the presence of two photosensitizing cyclic antibiotics, tetracycline and demethylchlortetracycline. To test whether or not the oxygenation of arachidonic acid was related to the biosynthesis of prostaglandins, [I- 14 C]-arachidonic acid was incubated with calf skin acetone powder in the presence of UV-irradiation and the cyclic antibiotics. Prostaglandin biosynthesis from arachidonic acid by the calf skin microsomal acetone powder was enhanced after exposure to UV-irradiation at 254 nm and moderately at 360 nm. Incubation in the presence of demethylchlortetra-cycline (0.2 mM) increased prostaglandin biosynthesis approximately 95% over control by UV-irradiation at 254 nm. No significant stimulation of prostaglandin biosynthesis was observed at 360 nm. Non-photosensitizing antibiotics had no effect either on the oxygenation of arachidonic acid or on the biosynthesis of prostaglandin with or without UV-irradiation. It is suggested that the inflammatory reactions associated with these photo-reactive antibiotics may in part, be via the biosynthesis and release of the prostaglandins which are known to produce cutaneous inflammatory reactions. (author)
Evaluation of extracts of Moringa oleifera Lam seeds obtained with NaCl and their effects on water treatment - doi: 10.4025/actascitechnol.v34i3.9605

Directory of Open Access Journals (Sweden)

Vanessa Jurca Seolin

2012-05-01

Full Text Available Several natural coagulants have been studied for use in water treatment. The seed of Moringa oleifera Lam, for example, is a natural coagulant whose extract has been mentioned as effective not only for removing color, turbidity, and compounds with absorption at UV-254 nm, but also for significantly reducing the amount of sludge and bacteria in wastewaters. Therefore, the present study (1 evaluated the molecular weight of the extract of Moringa oleifera seed utilizing electrophoresis, and (2 compared the efficiency of different extracts obtained, using solutions of NaCl (0.01 M, 0.1 M and 1 M, distilled water, and Moringa oleifera Lam seed, acting as a natural coagulant in order to obtain drinking water. The tests were performed in Jar Test, and the effectiveness of the process was assessed regarding the removal of color, turbidity and UV-254 nm. It was observed that the molecular weight found in this study is consistent with literature data. Moreover, the highest removal efficiency of color, turbidity, and UV-254 nm occurred with 1M NaCl solution, with coagulant concentration between 100 and 300 mg L-1. The results obtained evidenced that the seed of Moringa oleifera Lam is a great alternative for use as a coagulant in drinking water treatment systems.
Importance of (n,xn) reactions in evaluating kinetic parameters of subcritical assemblies: from classic to modern formalism

Energy Technology Data Exchange (ETDEWEB)

Talamo, Alberto; Gohar, Yousry, E-mail: alby@anl.gov [Argonne National Laboratory, Lemont, IL (United States); Dulla, Sandra; Ravetto, Piero [Politecnico di Torino (Italy)

2011-07-01

The importance of (n,xn) reactions must be taken into consideration while calculating the kinetic parameters of subcritical assemblies driven by an external neutron source. This study is divided into two parts, the first part is dedicated to the classic definition of the neutron source multiplication factor and two alternative calculation methodologies are compared. The second part considers a new definition of the kinetic parameters for subcritical assemblies, with particular emphasis on the delayed neutron fraction and generation time. This new definition has been modified to take into account the external neutron source and (n,xn) reactions, which increase the fraction of prompt neutrons. The developed theoretical framework has been applied by Monte Carlo and deterministic calculations to the YALINA Thermal subcritical assembly in Belarus. This facility can be driven by californium, deuterium-deuterium (D-D), or deuterium-tritium (D-T) external neutron sources. For the D-T neutron source, (n,xn) reactions must be taken into account in order to produce accurate results because the average energy of D-T source neutrons is 14.1 MeV, a value much higher than the threshold energy of the (n,2n) cross section of uranium isotopes. (author)
Importance of (n,xn) reactions in evaluating kinetic parameters of subcritical assemblies: from classic to modern formalism

International Nuclear Information System (INIS)

Talamo, Alberto; Gohar, Yousry; Dulla, Sandra; Ravetto, Piero

2011-01-01

The importance of (n,xn) reactions must be taken into consideration while calculating the kinetic parameters of subcritical assemblies driven by an external neutron source. This study is divided into two parts, the first part is dedicated to the classic definition of the neutron source multiplication factor and two alternative calculation methodologies are compared. The second part considers a new definition of the kinetic parameters for subcritical assemblies, with particular emphasis on the delayed neutron fraction and generation time. This new definition has been modified to take into account the external neutron source and (n,xn) reactions, which increase the fraction of prompt neutrons. The developed theoretical framework has been applied by Monte Carlo and deterministic calculations to the YALINA Thermal subcritical assembly in Belarus. This facility can be driven by californium, deuterium-deuterium (D-D), or deuterium-tritium (D-T) external neutron sources. For the D-T neutron source, (n,xn) reactions must be taken into account in order to produce accurate results because the average energy of D-T source neutrons is 14.1 MeV, a value much higher than the threshold energy of the (n,2n) cross section of uranium isotopes. (author)
Neutron activation determination of gold in technogenic raw materials with different mineral composition

Directory of Open Access Journals (Sweden)

Yudakov Aleksandr A.

2015-01-01

Full Text Available The methods used to determine the gold content in the technogenic objects of gold mining were analyzed regarding their non-homogeneity and complexity of chemical and mineral compositions. A possible application of the neutron activation analysis with the use of the californium source of neutrons for determining the content of fine-grained and extra-fine-grained gold in the technogenic objects, including the bottom-ash waste of energy providers, is considered. It was demonstrated that the chemical composition of the sample affects the neuron flux distribution in the sample, which can essentially distort the results of the neutron activation analysis. In order to eliminate possible systematic errors investigations of the effect of the sample mineral composition on the results of the gold determination using the neutron activation analysis were carried out. Namely, a large mass of rock (3-5 kg was loaded into an activation zone using four matrix types such as silicate, carbon-containing, iron-containing, and titanium magnetite. It was shown that there wereno significant difference between the dispersal of the fluxes of thermal and resonance neutrons emitted from 252Cf during activation of the gold-containing technogenic samples with different mineral compositions.
A technique for combining neutron and gamma-ray data into a single assay value

International Nuclear Information System (INIS)

Pickrell, M.M.; Mercer, D.; Sharpe, T.J.

1998-01-01

The authors explored the potentials of using both neutron and gamma-ray measurements on a single item and combining these data into a single assay value. The purpose was to improve assay capability for sample matrices that are difficult to measure. They chose an empirical approach because they wanted to address difficult-to-measure items for which the assay problem is complex. They used the tomographic gamma scanner; a passive, high-efficiency neutron counter with add-a-source and multiplicity; and an active neutron, californium shuffler to obtain measurements. Twenty-four 200-L drums were measured with various matrices using all three machines. The matrices were chosen specifically to spain the difficult-to-measure assay problems for some or all of the instruments. For example, the authors measured a drum filled with concrete and another filled with metal. The data from these measurements were analyzed using the alternating conditional expectation algorithm, which is one of a class of generalized additive models. Other data fusion algorithms are also possible and are being explored. The intent was to find ways to combine the data that would reduce the matrix-induced measurement error

Activation analysis of stainless steel flux monitors using 252Cf neutron sources

International Nuclear Information System (INIS)

Williams, J.G.; Newton, T.H. Jr.; Cogburn, C.O.

1984-01-01

Activation analysis was performed on stainless steel beads from a chain which is used in reactor pressure vessel surveillance experiments at the Arkansas Power and Light Company reactors. The beads allow monitoring of two fast and three thermal neutron induced reactions: 58 Ni(n,p) 58 Co, 54 Fe(n,p) 54 Mn, 58 Fe(n,γ) 59 Fe, 59 Co(n,γ) 60 Co and 50 Cr(n,γ) 51 Cr. The analysis was performed using 12 beads from various positions along 5 different batches of chain and standard materials in an H 2 O moderator tank using two intense californium sources which had a total neutron emission rate of 3.97 x 10 10 /s. Semiconductor gamma spectrometers were used to count the products of the above reactions in the specimens. The percentage by weight of the iron, chromium and cobalt in the beads were found to be 62.1%, 20.2% and 0.120%, respectively. The excellent uniformity found in the bead compositions demonstrates the reproducibility of the experimental techniques and enhances considerably the value of the beads as neutron flux montitors
Interface detection by neutron scattering

International Nuclear Information System (INIS)

De Monchy, A.R.; Kok, C.A.; Dorrepaal, J.

1979-01-01

A method and apparatus for detecting an interface of materials having different hydrogen content present in a metal vessel or pipe eg. made of steel, are described. Steel walls of columns, reactors, pipelines etc can be monitored. It is very suitable for detection of liquid water or hydrocarbons present in gas pipelines and also for the detection of a liquid hydrocarbon in a vessel or column. A series of measurements of the hydrogen density of the contents of a vessel or pipe are made using at least one californium-252 neutron source located near the outer side of the pipe. Neutrons are emitted and are scattered by the contents of the pipe. At least one neutron detector is located near the outer side of the metal wall. The detectors have a higher sensitivity for scattered neutrons (from the light hydrogen nuclei present in water or hydrocarbons). A source of 0.1 - 1 micrograms produces enough neutrons for most technical applications so the handling is relatively safe although shielding is advocated. The detectors contain helium-3 at a pressure of about 10 bar. Current pulses from the detector are counted. (U.K.)
MinT: Middleware for Cooperative Interaction of Things.

Science.gov (United States)

Jeon, Soobin; Jung, Inbum

2017-06-20

This paper proposes an Internet of Things (IoT) middleware called Middleware for Cooperative Interaction of Things (MinT). MinT supports a fully distributed IoT environment in which IoT devices directly connect to peripheral devices easily construct a local or global network, and share their data in an energy efficient manner. MinT provides a sensor abstract layer, a system layer and an interaction layer. These enable integrated sensing device operations, efficient resource management, and active interconnection between peripheral IoT devices. In addition, MinT provides a high-level API to develop IoT devices easily for IoT device developers. We aim to enhance the energy efficiency and performance of IoT devices through the performance improvements offered by MinT resource management and request processing. The experimental results show that the average request rate increased by 25% compared to Californium, which is a middleware for efficient interaction in IoT environments with powerful performance, an average response time decrease of 90% when resource management was used, and power consumption decreased by up to 68%. Finally, the proposed platform can reduce the latency and power consumption of IoT devices.
Design of active-neutron fuel rod scanner

International Nuclear Information System (INIS)

Griffith, G.W.; Menlove, H.O.

1996-01-01

An active-neutron fuel rod scanner has been designed for the assay of fissile materials in mixed oxide fuel rods. A 252 Cf source is located at the center of the scanner very near the through hole for the fuel rods. Spontaneous fission neutrons from the californium are moderated and induce fissions within the passing fuel rod. The rod continues past a combined gamma-ray and neutron shield where delayed gamma rays above 1 MeV are detected. We used the Monte Carlo code MCNP to design the scanner and review optimum materials and geometries. An inhomogeneous beryllium, graphite, and polyethylene moderator has been designed that uses source neutrons much more efficiently than assay systems using polyethylene moderators. Layers of borated polyethylene and tungsten are used to shield the detectors. Large NaI(Tl) detectors were selected to measure the delayed gamma rays. The enrichment zones of a thermal reactor fuel pin could be measured to within 1% counting statistics for practical rod speeds. Applications of the rod scanner include accountability of fissile material for safeguards applications, quality control of the fissile content in a fuel rod, and the verification of reactivity potential for mixed oxide fuels. (orig.)
Sources of Radioactive Isotopes for Dirty Bombs

Science.gov (United States)

Lubenau, Joel

2004-05-01

From the security perspective, radioisotopes and radioactive sources are not created equal. Of the many radioisotopes used in industrial applications, medical treatments, and scientific research, only eight, when present in relatively large amounts in radioactive sources, pose high security risks primarily because of their prevalence and physical properties. These isotopes are americium-241, californium-252, cesium-137, cobalt-60, iridium-192, radium-226, plutonium-238, and strontium-90. Except for the naturally occurring radium-226, nuclear reactors produce the other seven in bulk commercial quantities. Half of these isotopes emit alpha radiation and would, thus, primarily pose internal threats to health; the others are mainly high-energy gamma emitters and would present both external and internal health hazards. Therefore, the response to a "dirty bomb" event depends on what type of radioisotope is chosen and how it is employed. While only a handful of major corporations produce the reactor-generated radioisotopes, they market these materials to thousands of smaller companies and users throughout the world. Improving the security of the high-risk radioactive sources will require, among other efforts, cooperation among source suppliers and regulatory agencies.
[Using UV-Vis Absorbance for Characterization of Maturity in Composting Process with Different Materials].

Science.gov (United States)

Zhao, Yue; Wei, Yu-quan; Li, Yang; Xi, Bei-dou; Wei, Zi-min; Wang, Xing-lei; Zhao, Zhi-nan; Ding, Jei

2015-04-01

The present study was conducted to assess the degree of humification in DOM during composting using different raw materials, and their effect on maturity of compost based on UV-Vis spectra measurements and chemometrics method. The raw materials of composting studied included chicken manure, pig manure, kitchen waste, lawn waste, fruits and vegetables waste, straw waste, green waste, sludge, and municipal solid waste. During composting, the parameters of UV-Vis spectra of DOM, including SUVA254 , SUVA280 , E250/E365, E4/E6, E2/E4, E2/E6, E253/E203, E253/E220, A226-400, S275-295 and S350-400 were calculated, Statistical analysis indicated that all the parameter were significantly changed during composting. SUVA254 and SUVA280 of DOM were continuously increased, E250/E365 and E4/E6 were continuously decreased in DOM, while A226-400, S275-295 and S350-400 of DOM at the final stage were significantly different with those at other stages of composting. Correlation analysis indicated that the parameters were significantly correlated with each other except for E2/E4 and E235/E203. Furthermore, principal component analysis suggested that A226-400, SUVA254, S350-400, SUVA280 and S275~295 were reasonable parameters for assessing the compost maturity. To distinguish maturity degree among different composts, hierarchical cluster analysis, an integrated tool utilizing multiple UV-Vis parameters, was performed based on the data (A226-400, SUVA254, S350-400, SUVA280 and S275-295) of DOM derived from the final stage of composting. Composts from different sources were clustered into 2 groups. The first group included chicken manure, pig manure, lawn waste, fruits and vegetables waste, green waste, sludge, and municipal solid waste characterized by a lower maturity degree, and the second group contained straw waste and kitchen waste associated with a higher maturity degree. The above results suggest that a multi-index of UV-Vis spectra could accurately evaluate the compost maturity
Dissolved organic matter signatures vary between naturally acidic, circumneutral and groundwater-fed freshwaters in Australia.

Science.gov (United States)

Holland, Aleicia; Stauber, Jenny; Wood, Chris M; Trenfield, Melanie; Jolley, Dianne F

2018-06-15

Dissolved organic matter (DOM) plays important roles in both abiotic and biotic processes within aquatic ecosystems, and these in turn depend on the quality of the DOM. We collected and characterized chromophoric DOM (CDOM) from different Australian freshwater types (circumneutral, naturally acidic and groundwater-fed waterways), climatic regions and seasons. CDOM quality was characterized using absorbance and fluorescence spectroscopy. Excitation emission scans followed by parallel factor (PARAFAC) analysis showed that CDOM was characterized by three main components: protein-like, fulvic-like and humic-like components commonly associated with various waters globally in the Openfluor database. Principal component analysis showed that CDOM quality varied between naturally acidic, circumneutral and groundwater-fed waters, with unique CDOM quality signatures shown for each freshwater type. CDOM quality also differed significantly within some sites between seasons. Clear differences in dominant CDOM components were shown between freshwater types. Naturally acidic waters were dominated by highly aromatic (as indicated by the specific absorbance co-efficient (SAC 340 ) and the specific UV absorbance (SUVA 254 ) values which ranged between 31 and 50 cm 2  mg -1 and 3.9-5.7 mg C -1  m -1 respectively), humic-like CDOM of high molecular weight (as indicated by abs 254/365 which ranged from 3.8 to 4.3). In contrast, circumneutral waters were dominated by fulvic-like CDOM of lower aromaticity (SAC 340 : 7-21 cm 2  mg -1 and SUVA 254 : 1.5-3.0 mg C -1  m -1 ) and lower molecular weight (abs 254/365 5.1-9.3). The groundwater-fed site had a higher abundance of protein-like CDOM, which was the least aromatic (SAC 340 : 2-5 cm 2  mg -1 and SUVA 254 : 0.58-1.1 mg C -1  m -1 ). CDOM was generally less aromatic, of a lower molecular weight and more autochthonous in nature during the summer/autumn sampling compared to winter/spring. Significant
Systema Naturae. Classification of living things.

OpenAIRE

Alexey Shipunov

2007-01-01

Original classification of living organisms containing four kingdoms (Monera, Protista, Vegetabilia and Animalia), 60 phyla and 254 classes, is presented. The classification is based on latest available information.
75 FR 39040 - National Register of Historic Places; Notification of Pending Nominations and Related Actions

Science.gov (United States)

2010-07-07

... Manistee Iron Works Machine Shop, 254 River St., Manistee, 10000477 Wayne County Rosedale Gardens Historic... Berry Morot Car Service Building, (Auto-Related Resources of St. Louis, Missouri [[Page 39041
Johannes Müller, Exile Memories and the Dutch Revolt: The Narrated Diaspora, 1550-1750

Directory of Open Access Journals (Sweden)

C.A. (Annemieke Romein

2017-10-01

Full Text Available Johannes Müller, Exile Memories and the Dutch Revolt: The Narrated Diaspora, 1550-1750 (Dissertation Leiden University 2014; Leiden/ Boston: Brill. 2016, 254 pp., ISBN 9789004315914.
ISSN 2073-9990 East Cent Afr J Surg

African Journals Online (AJOL)

Appendicular perforation (25.4%) and gangrenous intussusception (23.8%) were the ... Successful management of peritonitis requires timely surgical intervention to ... perforations (especially peptic ulcer perforations) are more common in ...
76 FR 12364 - Agency Information Collection Activities: Bonded Warehouse Regulations

Science.gov (United States)

2011-03-07

... respondents or record keepers from the collection of information (a total capital/ startup costs and... Total Annual Responses: 9,254. Estimated Time per Response: 32 minutes. Estimated Total Annual Burden...
Effect of Permanganate Preoxidation to Natural Organic Matter and Disinfection by-Products Formation Potential Removal

Science.gov (United States)

Hidayah, E. N.; Yeh, H. H.

2018-01-01

Laboratory scale experiments was conducted to examine effect of permanganate (KMnO4) peroxidation in characterizing and to remove natural organic matter (NOM) in source water. The experimental results shows that increasing permanganate dosage could decreased aromatic matter, as indicated by decreasing UV254 and SUVA value about 23% and 28%, respectively. It seems that permanganate preoxidation caused the breakdown of high molecular weight (MW) organics into low MW ones, as represented by increasing NPDOC about 10%. Further, disinfection by-products formation potential (DBPFP) in terms of trihalomethanes formation potential (THMFP) and haloacetic acid formation potential (HAAP) decreased about 15% and 23%, respectively. HAAFP removal is higher than THMFP removal and that DPBFP removal is consistent with UV254 and NPDOC removal.
Communication received from the permanent mission of Australia on behalf of the Member States of the nuclear suppliers group

International Nuclear Information System (INIS)

1997-01-01

The document reproduces the text of a letter dated 13 August 1997 received by the Director General of the IAEA from the Permanent Mission of Australia to the Agency on behalf of the Member States of the 'Nuclear Suppliers Group (NSG)'. Attached to this letter was a paper entitled 'The Nuclear Suppliers Group: Its origins, role and activities'. The purpose of the letter and the attached paper was to provide detailed background to the origins of guidelines that govern the export of items exclusively for nuclear use and the export of nuclear related dual-use items and technologies. These guidelines were published by the Agency in documents INFCIRC/254/Rev.3/Part 1 and INFCIRC/254/Rev.2/Part 2/Mod.1
The competitive action of UV of different wavelengths of the survival of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Ivanova, Eh.V.; Pospelov, M.E.; Strakhovskaya, M.G.; Frajkin, G.Ya.

1982-01-01

During investigation into combined action of different wavelengths of UV spectrum on Saccharomyces cerevisiae yeast (strains XII and CI-9) it was established that 334 nm preliminary irradiation causes photoprotection of cells from lethal action of 254 and 313 nm UV-rays. During 334 postradiation irradiation strengthening of lethal action of 254 and 313 nm UV-rays for strain XII, not capable of photoreactivation, is observed. Using specific inhibitor of serotonin-biosynthesis- parachlorophenyl alanine it is shown that 334 nm serotonin synthesis induced by light lies in the base of mechanism of both effects. The effect of postradiation action of 334 nm light for strain CI-9, capable of photoreactivation, depends on interaction of two different photobiological reactions caused by light, photoreactivation and photoinduced synthesis of serotonin
UV induced photoluminescence and thermally stimulated luminescence of ThO{sub 2}:Tb{sup 3+} phosphor

Energy Technology Data Exchange (ETDEWEB)

Godbole, S.V.; Nagpal, J.S.; Page, A.G. E-mail: agpage@magnum.barc.ernet.in

2000-08-15

Thorium oxide doped with trivalent terbium ions offers itself as a novel phosphor with its photo- and thermally-stimulated luminescence (PL and TSL) characteristics showing a marked change on sustained exposure to 254 and 365 nm ultraviolet (UV) radiation. The reduction in luminescence intensity of Tb{sup 3+} ions, on irradiation with 254 nm photons and subsequent restoration on exposure to 365 nm, has been correlated with the complimentary behaviour in UV-induced TSL. These changes are, in turn, ascribed to inter-configurational (f-d) transitions and e-h formation and recombination processes. UV radiation induced TSL output increases linearly with incident UV radiant energy at a constant radiation flux; however, for a fixed exposure, TSL output increases with increase in radiant flux.
UV induced photoluminescence and thermally stimulated luminescence of ThO2:Tb3+ phosphor

International Nuclear Information System (INIS)

Godbole, S.V.; Nagpal, J.S.; Page, A.G.

2000-01-01

Thorium oxide doped with trivalent terbium ions offers itself as a novel phosphor with its photo- and thermally-stimulated luminescence (PL and TSL) characteristics showing a marked change on sustained exposure to 254 and 365 nm ultraviolet (UV) radiation. The reduction in luminescence intensity of Tb 3+ ions, on irradiation with 254 nm photons and subsequent restoration on exposure to 365 nm, has been correlated with the complimentary behaviour in UV-induced TSL. These changes are, in turn, ascribed to inter-configurational (f-d) transitions and e-h formation and recombination processes. UV radiation induced TSL output increases linearly with incident UV radiant energy at a constant radiation flux; however, for a fixed exposure, TSL output increases with increase in radiant flux
LANDFILL LEACHATES PRETREATMENT BY OZONATION

Directory of Open Access Journals (Sweden)

Jacek Leszczyński

2016-06-01

Full Text Available In this paper, the application of ozonation processes for stabilized landfill leachate treatment was investigated. The leachate came from a municipal sanitary landfill located nearby Bielsk Podlaski. The average values of its main parameters were: pH 8.23; COD 870 mgO2/dm3; BOD 90 mgO2/dm3; NH4+ 136.2 mgN/dm3; UV254 absorbance 0.312 and turbidity 14 NTU. The ozone dosages used were in the range of 115.5 to 808.5 mgO3/dm3 of the leachate. The maximum COD, color and UV254 absorbance removal wa.5 mgO3/dm3. After oxidation, the ratio of BOD/COD was increased from 0.1 up to 0.23.
Enforcement and Effectiveness of Consumer Law in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Pauknerová, Monika; Skalská, H.

2017-01-01

Roč. 7, č. 4 (2017), s. 243-254 ISSN 1805-8396 Institutional support: RVO:68378122 Keywords : consumer law * enforcement * alternative dispute resolution Subject RIV: AG - Legal Sciences OBOR OECD: Law
Magnetically responsive biological materials and their applications

Czech Academy of Sciences Publication Activity Database

Šafařík, Ivo; Pospíšková, K.; Baldíková, E.; Šafaříková, Miroslava

2016-01-01

Roč. 7, č. 4 (2016), s. 254-261 ISSN 0976-3961 Institutional support: RVO:60077344 Keywords : adsorbents * biological materials * carriers * magnetic modification * whole-cell biocatalyst Subject RIV: EI - Biotechnology ; Bionics

Je to neobyčejně milý člověk, ten znamenitý Einstein! (Reflexe Viktora Trkala ze studijního pobytu na univerzitě v Leidenu v letech 1919-1920)

Czech Academy of Sciences Publication Activity Database

Těšínská, Emilie

2015-01-01

Roč. 60, č. 3 (2015), s. 239-254 ISSN 0032-2423 Institutional support: RVO:68378114 Keywords : general theory of relativity * Albert Einstein * history of science * Viktor Trkal Subject RIV: AB - History
CAMEX-4 NOAA LYMAN-ALPHA HYGROMETER V1

Data.gov (United States)

National Aeronautics and Space Administration — Ozone is measured in situ using a photometer consisting of a mercury lamp, two sample chambers and two detectors. The detectors measure the 254nm radiation...
Glia: the fulcrum of brain diseases

Czech Academy of Sciences Publication Activity Database

Giaume, C.; Kirchhoff, F.; Matute, C.; Reichenbach, A.; Verkhratsky, Alexei

2007-01-01

Roč. 14, - (2007), s. 1324-1335 ISSN 1350-9047 Institutional research plan: CEZ:AV0Z50390512 Keywords : Glia * Astrocyte * Oligodendrocyte Subject RIV: FH - Neurology Impact factor: 8.254, year: 2007
Bactericidal effect of the photocatalystic reaction of titanium dioxide using visible wavelengths on Streptococcus mutans biofilm.

Science.gov (United States)

Kim, Chan-Hee; Lee, Eun-Song; Kang, Si-Mook; de Josselin de Jong, Elbert; Kim, Baek-Il

2017-06-01

The aim of this study was to determine the effect of titanium dioxide (TiO 2 ) photocatalysis induced by the application of clinically acceptable visible light at 405nm on the growth of Streptococcus mutans biofilms. S. mutans biofilms were grown on a hydroxyapatite (HA) disk and deposited in a rutile-type TiO 2 solution at a concentration of 0.1mg/mL. TiO 2 photocatalysis was measured for exposure to visible light (405nm) and ultraviolet (UV) light (254nm) produced by light-emitting diodes for 10, 20, 30, and 40min. After two treatments, the number of colonies formed in the final S. mutans biofilm on the HA disk were measured to confirm their viability, and the morphological changes of S. mutans were evaluated using scanning electronic microscopy. The bactericidal effects of 254- and 405-nm light resulted in > 5-log and 4-log reductions, respectively (p7-log reduction after 40min of treatment in both treatment groups relative to the control group. It was confirmed that the antibacterial effect could be shown by causing the photocatalytic reaction of TiO 2 in S. mutans biofilm even at the wavelength of visible light (405nm) as at the wavelength of ultraviolet light (254nm). Copyright © 2017 Elsevier B.V. All rights reserved.
TREATMENT OF LANDFILL LEACHATE BY COUPLING COAGULATION-FLOCCULATION OR OZONATION TO GRANULAR ACTIVATED CARBON ADSORPTION.

Science.gov (United States)

Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H

2015-01-01

A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation.
Roles of singlet oxygen and triplet excited state of dissolved organic matter formed by different organic matters in bacteriophage MS2 inactivation

KAUST Repository

Rosado-Lausell, Sahid L.; Wang, Hanting; Gutié rrez, Leonardo A.; Romero-Maraccini, Ofelia C.; Niu, Xi-Zhi; Gin, Karina; Croue, Jean-Philippe; Nguyen, Thanh Ha

2013-01-01

Inactivation of bacteriophage MS2 by reactive oxygen species (ROS) and triplet excited state of dissolved organic matter (3DOM*) produced by irradiation of natural and synthetic sensitizers with simulated sunlight of wavelengths greater than 320nm was investigated. Natural sensitizers included purified DOM isolates obtained from wastewater and river waters, and water samples collected from Singapore River, Stamford Canal, and Marina Bay Reservoir in Singapore. Linear correlations were found between MS2 inactivation rate constants (kobs) and the photo-induced reaction rate constants of 2,4,6-trimethylphenol (TMP), a probe compound shown to react mainly with 3DOM*. Linear correlations between MS2 kobs and singlet oxygen (1O2) concentrations were also found for both purified DOM isolates and natural water samples. These correlations, along with data from quenching experiments and experiments with synthetic sensitizers, Rose Bengal (RB), 3'-methoxyacetophenone (3'-MAP), and nitrite (NO2-), suggest that 1O2, 3DOM*, and hydroxyl radicals (•OH) could inactivate bacteriophage MS2. Linear correlations between MS2 kobs and Specific Ultraviolet Absorption determined at 254nm (SUVA254) were also found for both purified DOM isolates and natural samples. These results suggest the potential use of TMP as a chemical probe and SUVA254 as an indicator for virus inactivation in natural and purified DOM water samples. © 2013 Elsevier Ltd.
Reductions of dissolved organic matter and disinfection by-product precursors in full-scale wastewater treatment plants in winter.

Science.gov (United States)

Xue, Shuang; Jin, Wujisiguleng; Zhang, Zhaohong; Liu, Hong

2017-07-01

The reductions of dissolved organic matter (DOM) and disinfection byproduct precursors in four full-scale wastewater treatment plants (WWTPs) (Liaoning Province, China) where different biological treatment processes were employed in winter were investigated. The total removal efficiencies of dissolved organic carbon (DOC), ultraviolet light at 254 nm (UV-254), trihalomethane formation potential (THMFP), and haloacetic acid formation potential (HAAFP) were in the range of 70.3-76.0%, 49.6-57.3%, 54.4-65.0%, and 53.7-63.8% in the four WWTPs, respectively. The biological treatment was the predominant process responsible for the removal of DOC, THMFP, and HAAFP in WWTPs. Differences in the reduction of UV-254 were not significant (p > 0.05) among biochemical reaction pool, secondary sedimentation tank, and disinfection tank. Biological aerated filter and suspended carrier activated sludge processes achieved higher DOM removal than the conventional active sludge and anaerobic-anoxic-oxic processes. Hydrophobic neutral and hydrophilic fraction were removed to a higher degree through biological treatment than the other three DOM fractions. HAAFP removal was more efficient than THMFP reduction during biological treatment. During primary treatment, fluorescent materials in secondary sedimentation tanks were preferentially removed, as compared to the bulk DOM. Humic-like fluorescent compounds were not readily eliminated during biological treatment. The fluorescent materials were more susceptible to chlorine than nonfluorescent compounds. Copyright © 2017. Published by Elsevier Ltd.
Roles of singlet oxygen and triplet excited state of dissolved organic matter formed by different organic matters in bacteriophage MS2 inactivation

KAUST Repository

Rosado-Lausell, Sahid L.

2013-09-01

Inactivation of bacteriophage MS2 by reactive oxygen species (ROS) and triplet excited state of dissolved organic matter (3DOM*) produced by irradiation of natural and synthetic sensitizers with simulated sunlight of wavelengths greater than 320nm was investigated. Natural sensitizers included purified DOM isolates obtained from wastewater and river waters, and water samples collected from Singapore River, Stamford Canal, and Marina Bay Reservoir in Singapore. Linear correlations were found between MS2 inactivation rate constants (kobs) and the photo-induced reaction rate constants of 2,4,6-trimethylphenol (TMP), a probe compound shown to react mainly with 3DOM*. Linear correlations between MS2 kobs and singlet oxygen (1O2) concentrations were also found for both purified DOM isolates and natural water samples. These correlations, along with data from quenching experiments and experiments with synthetic sensitizers, Rose Bengal (RB), 3\\'-methoxyacetophenone (3\\'-MAP), and nitrite (NO2-), suggest that 1O2, 3DOM*, and hydroxyl radicals (•OH) could inactivate bacteriophage MS2. Linear correlations between MS2 kobs and Specific Ultraviolet Absorption determined at 254nm (SUVA254) were also found for both purified DOM isolates and natural samples. These results suggest the potential use of TMP as a chemical probe and SUVA254 as an indicator for virus inactivation in natural and purified DOM water samples. © 2013 Elsevier Ltd.
A facile route to synthesis of CoPt magnetic nanoparticles

International Nuclear Information System (INIS)

Liu, Yang; Yang, Yanting; Zhang, Yongjun; Wang, Yaxin; Zhang, Xiaolong; Jiang, Yuhong; Wei, Maobin; Liu, Yanqing; Liu, Xiaoyan; Yang, Jinghai

2013-01-01

Graphical abstract: CoPt NPs are successfully synthesized by sol–gel method. Different distinct particle sizes with narrow particle size distribution of CoPt nanoparticles are obtained. The maximum coercivity of 254,720.3 A/m is obtained for 800 °C heat-treated sample. Display Omitted Highlights: ► L1 0 -CoPt NPs with FCT structure are successfully synthesized by sol–gel method. ► The maximum value of 254,720.3 A/m is obtained for the samples heated at 800 °C. ► The synthetic route proposed in this study is less toxic and easy-to-handle. -- Abstract: The face-centered tetragonal (FCT) ordered L1 0 CoPt nanoparticles (NPs) are prepared by the sol–gel method. Their structure and magnetic properties are characterized by the X-ray diffraction (XRD), the transmission electron microscope (TEM) and the vibrating sample magnetometer (VSM). The results indicate that the CoPt NPs heated at 400 °C are the disordered face-centered cubic (FCC) structure, whereas the samples annealed at the temperature above 600 °C exhibit an ordered FCT structure. TEM images show the increase of the particle size as the annealing temperature increases. SAED images show the appearance of the L1 0 phase at 800 °C, and the maximum coercivity is 254,720.3 A/m.
Feasibility and desirability of employing the thorium fuel cycle for power generation - 254

International Nuclear Information System (INIS)

Sehgal, B.R.

2010-01-01

Thorium fuel cycle for nuclear power generation has been considered since the very start of the nuclear power era. In spite of a very large amount of research, experimentation, pilot scale and prototypic scale installations, the thorium fuel was not adopted for large scale power generation [1,2]. This paper reviews the developments over the years on the front and the back-end of the thorium fuel cycle and describes the pros and cons of employing the thorium fuel cycle for large generation of nuclear power. It examines the feasibility and desirability of employing the thorium fuel cycle in concert with the uranium fuel cycle for power generation. (authors)
16 CFR 254.3 - Misrepresentation of extent or nature of accreditation or approval.

Science.gov (United States)

2010-01-01

...) Misrepresent that students successfully completing a course or program of instruction can transfer the credit... subject of unsolicited testimonials or endorsements from former students. It is deceptive for an industry member to use testimonials or endorsements that do not accurately reflect current practices of the school...
Printed wax masks for 254 nm deep-UV pattering of PMMA-based microfluidics

KAUST Repository

Fan, Yiqiang; Liu, Yang; Li, Huawei; Foulds, Ian G.

2012-01-01

This paper reports a new technique for masking deep-UV exposure of poly(methyl methacrylate) (PMMA) using a printed wax mask. This technique provides an inexpensive and bulk fabrication method for PMMA structures. The technique involves the direct
Arno Rafael Cederberg ja Eesti ajalooteadus / Hans Kruus

Index Scriptorium Estoniae

Kruus, Hans, 1891-1976

2005-01-01

Soome ajalooprofessorist Arno Rafael Cederbergist (1885-1948). Tartu Ülikoolis töötades oli tema peamine õppe-ja uurimisaine Eesti ja Põhjamaade ajalugu. Ilm.: Eesti Kirjandus, 1935, nr. 6., lk. 254-255
Gender differences in seasonal movement of dice snakes in Histria, southeastern Romania

Czech Academy of Sciences Publication Activity Database

Kärvemo, S.; Carlsson, M.; Tudor, M.; Sloboda, M.; Mihalca, A. D.; Ghira, I.; Bel, L.; Modrý, David

2011-01-01

Roč. 18, 20 September 2011 (2011), s. 245-254 ISSN 0934-6643 Institutional support: RVO:60077344 Keywords : Squamata * Natrix tessellata * dice snake * seasonal movements * activity patterns * sex ratio Subject RIV: EG - Zoology
Carotenoid-protein interaction alters the S1 energy of hydroxyechinenone in the Orange Carotenoid Protein

Czech Academy of Sciences Publication Activity Database

Polívka, Tomáš; Chábera, P.; Kerfeld, C.A.

2013-01-01

Roč. 1827, č. 3 (2013), s. 248-254 ISSN 0005-2728 Institutional support: RVO:60077344 Keywords : orange-carotenoid protein * excited states * photoprotection Subject RIV: BO - Biophysics Impact factor: 4.829, year: 2013
37(4) All.cdr

African Journals Online (AJOL)

HP

. 254 responses or injuries to asphyxia. (Shakespare, 2012). Although overwhelming aspiration of regurgitated contents had been considered a potential cause of instant death in mature bovines (Lopez, 2012, Shakespare,. 2012; McEwen ...
Inverse gamma ray dose rate effect in californium-252 RBE experiment with human T-1 cells irradiated in vitro

International Nuclear Information System (INIS)

Todd, P.; Feola, J.M.

1986-01-01

Metabolically deoxygenated suspensions of human T-1 cells were used to determine the RBE in hypoxia of low dose rate (LDR) Cf-252 radiation compared to LDR gamma radiation. Based upon the initial portion of the survival curves the RBE was 5.0 ± 1.0 for all components of the Cf-252 radiation and 7.1 ± 1.7 for the neutrons alone. An inverse dose rate effect was observed for LDR gamma radiation in which greater cell sensitivity was observed at lower dose rates and longer irradiation periods. It was demonstrated that there was little or no sublethal damage repair or cell progression during LDR at 21 deg C, and the observed decrease in cell survival probability with increasing irradiation time at a given dose was attributable to reoxygenation of the cell suspensions during the course of LDR exposures. (Auth.)
Pharmacogenetic characterization of naturally occurring germline NT5C1A variants to chemotherapeutic nucleoside analogs

Science.gov (United States)

Saliba, Jason; Zabriskie, Ryan; Ghosh, Rajarshi; Powell, Bradford C; Hicks, Stephanie; Kimmel, Marek; Meng, Qingchang; Ritter, Deborah I; Wheeler, David A; Gibbs, Richard A; Tsai, Francis T F; Plon, Sharon E

2016-01-01

Background Mutations or alteration in expression of the 5’ nucleotidase gene family can confer altered responses to treatment with nucleoside analogs. While investigating leukemia susceptibility genes, we discovered a very rare p.L254P NT5C1A missense variant in the substrate recognition motif. Given the paucity of cellular drug response data from NT5C1A germline variation, we characterized p.L254P and eight rare variants of NT5C1A from genomic databases. Methods Through lentiviral infection, we created HEK293 cell lines that stably overexpress wildtype NT5C1A, p.L254P, or eight NT5C1A variants reported in the NHLBI Exome Variant server (one truncating and seven missense). IC50 values were determined by cytotoxicity assays after exposure to chemotherapeutic nucleoside analogs (Cladribine, Gemcitabine, 5-Fluorouracil). In addition, we used structure-based homology modeling to generate a 3D model for the C-terminal region of NT5C1A. Results The p.R180X (truncating), p.A214T, and p.L254P missense changes were the only variants that significantly impaired protein function across all nucleotide analogs tested (>5-fold difference versus WT; p<.05). Several of the remaining variants individually displayed differential effects (both more and less resistant) across the analogs tested. The homology model provided a structural framework to understand the impact of NT5C1A mutants on catalysis and drug processing. The model predicted active site residues within NT5C1A motif III and we experimentally confirmed that p.K314 (not p.K320) is required for NT5C1A activity. Conclusion We characterized germline variation and predicted protein structures of NT5C1A. Individual missense changes showed substantial variation in response to the different nucleoside analogs tested, which may impact patients’ responses to treatment. PMID:26906009
Utilizing Colored Dissolved Organic Matter to Derive Dissolved Black Carbon Export by Arctic Rivers

Science.gov (United States)

Stubbins, Aron; Spencer, Robert; Mann, Paul; Holmes, R.; McClelland, James; Niggemann, Jutta; Dittmar, Thorsten

2015-10-01

Wildfires have produced black carbon (BC) since land plants emerged. Condensed aromatic compounds, a form of BC, have accumulated to become a major component of the soil carbon pool. Condensed aromatics leach from soils into rivers, where they are termed dissolved black carbon (DBC). The transport of DBC by rivers to the sea is a major term in the global carbon and BC cycles. To estimate Arctic river DBC export, 25 samples collected from the six largest Arctic rivers (Kolyma, Lena, Mackenzie, Ob’, Yenisey and Yukon) were analyzed for dissolved organic carbon (DOC), colored dissolved organic matter (CDOM), and DBC. A simple, linear regression between DOC and DBC indicated that DBC accounted for 8.9 ± 0.3% DOC exported by Arctic rivers. To improve upon this estimate, an optical proxy for DBC was developed based upon the linear correlation between DBC concentrations and CDOM light absorption coefficients at 254 nm (a254). Relatively easy to measure a254 values were determined for 410 Arctic river samples between 2004 and 2010. Each of these a254 values was converted to a DBC concentration based upon the linear correlation, providing an extended record of DBC concentration. The extended DBC record was coupled with daily discharge data from the six rivers to estimate riverine DBC loads using the LOADEST modeling program. The six rivers studied cover 53% of the pan-Arctic watershed and exported 1.5 ± 0.1 million tons of DBC per year. Scaling up to the full area of the pan-Arctic watershed, we estimate that Arctic rivers carry 2.8 ± 0.3 million tons of DBC from land to the Arctic Ocean each year. This equates to ~8% of Arctic river DOC export, slightly less than indicated by the simpler DBC vs DOC correlation-based estimate. Riverine discharge is predicted to increase in a warmer Arctic. DBC export was positively correlated with river runoff, suggesting that the export of soil BC to the Arctic Ocean is likely to increase as the Arctic warms.
The Influence of Water Circulation on Dissolved Organic Matter Dynamics in Bald Head Creek

Science.gov (United States)

Lebrasse, M. C.; Osburn, C. L.; Bohnenstiehl, D. R.; He, R.

2016-12-01

Dissolved organic matter (DOM) plays an important role in biogeochemical cycles in estuaries such as tidal creeks draining coastal wetlands such as salt marshes. However, significant knowledge gaps remain regarding the quantity and quality of the DOM that tidally exchanges between salt marshes and their adjacent estuaries. Tidal movements play a central role in lateral exchanges of materials and bidirectional flow results in the mixing of DOM from marsh plants and estuarine DOM. The aim of this study was to better understand the role of water circulation on the distribution and quality of DOM in Bald Head Creek, a tributary to the Cape Fear River estuary in eastern North Carolina. Dissolved organic carbon (DOC) concentration, stable carbon isotopes, and chromophoric DOM (CDOM) absorbance at 254 nm (a254) were used to distinguish between DOM quantity and quality at three locations along the creek: Site 3 (upstream), Site 2 (middle stream), and Site 1 (near the creek mouth). Samples were collected over four tidal cycles between March-August 2016 and compared to time series data collected approximately weekly from 2014-2016. DOM characteristics differed substantially over the tidal cycle. Higher CDOM and DOC concentration were observed at low tide than at high tide at all three sites, suggesting greater export of carbon from the marsh into the creek as the tides recede. Analysis of CDOM quality based on specific UV absorbance at 254 nm (SUVA254) and spectral slope ratio (SR) showed that the marsh end-member (Site 3) source of DOM had greater aromaticity and higher molecular weight. Site 1 showed greater variability over the tidal cycle most likely due to a greater tidal influence, being closer to the mouth. Additionally, an unmanned surface vehicle (USV) and a hydrodynamic model were used to map water circulation and DOC concentration along the creek to compute exchanges with the adjacent estuary. Results suggest that estuarine OM dynamics are strongly controlled by

Some links on this page may take you to non-federal websites. Their policies may differ from this site.