Energy Technology Data Exchange (ETDEWEB)

Short communication.

International Nuclear Information System (INIS)

A multiwire proportional counter type detector with thin slits instead of wires is presented. It can detect either charged particles (positive or negative) or radiation. The detector can be used as a counter or as an image converter. In radiography, it can replace photographic film or TV camera systems. It can also be used to measure particle or radiation energy. The slits which replace wires in the anode are introduced between two parallel microstrip conductors with different potentials. A quasi-polar electric field is produced between these strips. To obtain high fields, the slits are extremely narrow. Microstrips less than a micron can be obtained, giving structural dimensions of a few microns, i.e., 100 times smaller than the spacing in a classic wire anode.

Energy Technology Data Exchange (ETDEWEB)

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. These technologies are: 1) Boron trifluoride (BF3)-filled proportional ...

International Nuclear Information System (INIS)

The atomic explosions in Hiroshima and Nagasaki made the name radiation itself become a nightmare. Notwithstanding this, radiation continued to serve the mankind specially in diagnosis of several human diseases and in the treatment of intractable malignancies. With their latest research tools biologists have now shown a significant shift in the earlier paradigm; even the concept that radiation initiates cancer appears to be no longer tenable. On the contrary, selective radiation doses inhibit growth of cancer cells and radiation in combination with many chemotherapeutic drugs, radiosensitizing chemicals and/or hyperthermia, is emerging as a new modality for cancer treatment which offers high therapeutic advantages. In addition, the deleterious effects of radiation can now be strategically counter poised by the use of many drugs and ...

Energy Technology Data Exchange (ETDEWEB)

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

Energy Technology Data Exchange (ETDEWEB)

In calibration measurements with low energy X-rays, a double peak effect appears in low pressure proportional counters with a helix, when used for simulation of tissue equivalent diameters considerably larger than 2 m. An interpretation of this phenomenon is discussed, based upon electron capture and electric field perturbation at the counter helix. A description of the physical processes is presented showing that the double peak effect is a problem in the case of helix counters (called also Rossi counters) for all simulated diameters. Conclusions are drawn on systematic errors introduced by the counter helix into microdosimetric spectra and anti y/sub D/ of photons and neutrons. The authors recommend to use cylindrical counters with optimized geometrical and electronic parameters rather than the spherical counters with a helix discussed.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

Science.gov (United States)

... Tanzania, and the attack on the USS COLE. ... vis another has no bearing on the legality of the attack. If the person attacked is a combatant, the use of ...

Energy Technology Data Exchange (ETDEWEB)

The paper presents a description of the physical processes governing the variations of the pulse rise-time which occur during the operation of the proportional counter and are due to varying either the count rate or the applied voltage. On the basis of the rise-time concept the differences in the count rate effect observed in various types of proportional counters are discussed.

International Nuclear Information System (INIS)

The 10.3-h "1"6"5Er, decaying by electron capture to stable "1"6"5Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in "1"6"5Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of "1"6"9Er and "1"7"1Er radioactive impurities in the reactor-produced "1"6"5Er sample are experimentally determined. Whole-body dose estimates for "1"6"5Er are given. These compare favorably with "9"9Tc dose.

International Nuclear Information System (INIS)

Pharmacokinetics is studied, radiation doses to patients when using domestic thallium-201 chloride in diagnosis of the heart ischemic disease is estimated; contribution into the total dose of thallium-201 (1.5 %), thallium-201 (0.2 %) and lead-201 + lead-203 (0.05 %) radionuclide impurities is also determined. Internal doses were estimated for a heterogeneous phantom of a standard man; the calculations were carried out using a computer. Scanning of patients which were treated with radiopharmaceuticals to be diagnosed was carried out using a whole body counter and gamma-chamber. Large intestine, kidneys and thyroid are the critical organs when using thallium-201 chloride. The highest contribution into the dose to organs and the whole body from thallium-200 and thallium-202 impurities being contained in thallium-201, doesn't exceed 8.6 %. The contribution into the dose from lead-201 and lead-203 may be ignored. Doses from thallium-199 preparation ...

Energy Technology Data Exchange (ETDEWEB)

Solid state nuclear track detectors (SSNTD) record radiation in the form of tracks. In the case of high track density, however, it is not always possible to distinguish each track separately. The track density might then be underestimated unless the loss of track number due to overlapping is compensated. An elaborated 'erosion' or curve fitting process is applied usually, for the separation of the overlapping tracks, to automatic track counting systems. This paper shows a much simpler correction method which was developed by the analogy of the correction equation for the dead time of GM counters. From a set of about 10 data obtained from high track density detectors, the equation for SSNTD can be determined by a least square fitting. Once the equation is found, true track density could be derived easily without any help of complex image processing or calculation, such as the erosion or curve fitting. This method also provides ...

International Nuclear Information System (INIS)

The ability of the Packard 2000 CA/LL liquid scintillation counter to reduce background count rates relies on pulse shape/duration analysis in which short duration organic scintillation events are discriminated from longer duration non-quenchable background events. A consequence of this is a loss in the counting efficiency. The results of this investigation indicate that much of the lost efficiency can be regained by sharpening the true #beta#"- pulse widths via the use of different scintillant combinations and by certain counter modifications. (author).

Energy Technology Data Exchange (ETDEWEB)

A multiple sampling dE/dx counter using a multiwire proportional chamber equipped with catbode pads was constructed for the multiple detection of dE/dx values along a particle trajectory. For low-energy particles this counter was proved to be useful as a Bragg-curve detector. At relativistic energies around E=14.6 GeV/nucleon good particle identification was obtained by cathode pad signals as well as anode signals for the range of projectile fragments from Z=1 (minimum ionization) up to a beam charge of Z=14. (orig.).

Science.gov (United States)

... keyboards, door knobs and counter tops, such surfaces should be cleaned with common household disinfectants regularly and after increased crowd contact. ...

Science.gov (United States)

... Page 25. US Department of Defense, Joint Operation Planning and Execution System, Vol 1, Planning Policies and Procedures (CJCSM 3122.01A). ...

International Nuclear Information System (INIS)

An investigation of the Ll x-#gamma# angular correlations following the decay of "2"0"7Bi is done by using a Si(Li) semiconductor counter as L x-ray detector. Coincidence measurements at five different angles were made between the 570-keV #gamma# ray (gated in the movable counter) and the Ll x spectrum (displayed in a multichannel analyzer).

Energy Technology Data Exchange (ETDEWEB)

Experimental results of ageing effects in proportional counters are presented. The measurements were carried out for 158 ZEUS-BAC gas system monitoring counters. Deterioration of the pulse height distribution in azimuth and along the anode wire are presented. The influence of water admixture on counting gas is also described. (orig.).

Science.gov (United States)

Large amounts of atmospheric dust are lifted from the North African deserts and are transported by the trade winds over the Caribbean region, especially during the summer months. How African dust particles influence the earth's radiative budget is not well understood because these particles are highly variable and their physical, optical, and chemical properties are poorly characterized, especially when they are atmospherically processed as are those that travel from Africa to the Caribbean region. Here we present results of aerosol measurements performed at Cape San Juan (CPR), a ground-based station located at the northeastern tip of the Caribbean island of Puerto Rico. We used a condensation particle counter to determine the particle number concentration, a sunphotometer (part of the AErosol RObotical NETwork, AERONET, aeronet.gsfc.nasa.gov) to determine volume size distributions and aerosol optical thickness, and a 3-wavelength ...

UK PubMed Central (United Kingdom)

BackgroundAcetaminophen, the major active metabolite of acetanilide in man, has become one of the most popular over-the-counter analgesic and antipyretic agents, consumed by millions...Full Text Available

Science.gov (United States)

In systems of fast decimal counters, there are three problems to be resolved: to study a bistable having a short switching time, to form with the aid of three bistables a circuit divisible by 5, and to normalize the input pulses. The solutions to these problems for the nonsecond scaler are presented. (J.S.R.)

International Nuclear Information System (INIS)

ASTROSAT, India's first dedicated astronomy satellite is slated for launch in 2007. The primary science objective of ASTROSAT is to explore the Universe using broad-band instruments covering optical, UV, soft X-ray and hard X-ray studies

UK PubMed Central (United Kingdom)

Cellular hypertrophy is regulated by coordinated pro- and antigrowth machineries. Foxo transcription factors initiate an atrophy-related gene program to counter hypertrophic growth. This study was designed...Full Text Available

International Nuclear Information System (INIS)

An array of multiwire proportional counters has been employed to image, in 'real-time', a collimated neutron beam produced at an electron linac facility. Test results are presented, along with a discussion of the advantages of this technique. (orig.).

International Nuclear Information System (INIS)

... organizations irradiation radiation doses radiation effects RADIATIONS.

International Nuclear Information System (INIS)

... halogenation ionizing radiations kinetics radiations reaction kinetics

CERN Document Server

Counting is among the most fundamental operations in computing. For example, counting the pth frequency moment has been a very active area of research, in theoretical computer science, databases, and data mining. When p=1, the task (i.e., counting the sum) can be accomplished using a simple counter. Compressed Counting (CC) is proposed for efficiently computing the pth frequency moment of a data stream signal A_t, where 0= 0, which includes the strict Turnstile model as a special case. For natural data streams encountered in practice, this restriction is minor. The underly technique for CC is what we call skewed stable random projections, which captures the intuition that, when p=1 a simple counter suffices, and when p = 1+/\\Delta with small \\Delta, the sample complexity of a counter system should be low (continuously as a function of \\Delta). We show at small \\Delta the sample complexity (number of projections) k = ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

Science.gov (United States)

... radiation during clinical therapy and exposures due to radiation accidents or attacks, in which the doses are uncontrolled ... only be used off-label in victims of radiation accidents or attacks. The idea...

Energy Technology Data Exchange (ETDEWEB)

A detector has been developed and used to measure dose distributions versus linear energy transfer to thin gas targets in spherical geometry from fast neutron irradiation of tissue-equivalent plastic and carbon. The detector is a hemispherical proportional counter with a Cs(T1) scintillator at the center of the hemisphere. The coincidence of the proportional counter signals constrain the measurements to charged particles traversing the radius of the hemisphere. The charged particle energy deposition distributions are directly measured for a known pathlength. The A-150 kerma factor was measured at a neutron energy of 14.8 MeV and is in agreement with tabulated values. The carbon kerma factor measurements are less than the tabulated value at 14.8 MeV. The alpha-particle production in carbon was measured for neutron energies from 14.1 to 14.8 MeV and is compared with existing data.

British Library Electronic Table of Contents (United Kingdom)

An experimental investigation on the air/water counter-current two-phase flow in a horizontal rectangular channel connected to an inclined riser has been conducted. This test-section representing a model of the hot leg of a pressurized water reactor is mounted between two separators in a pressurized experimental vessel. The cross-section and length of the horizontal part of the test-section are (0.25mx0.05m) and 2.59m, respectively, whereas the inclination angle of the riser is 50degree. The flow was captured by a high-speed camera in the bended region of the hot leg, delivering a detailed view of the stratified interface as well as of dispersed structures like bubbles and droplets. Countercurrent flow limitation (CCFL), or the onset of flooding, was found by analyzing the water levels mea...

Energy Technology Data Exchange (ETDEWEB)

By using a charge-sensitive preamplifier and methods of energy spectroscopy we investigated the response of a parallel plate avalanche counter in order to scan the Bragg curve. The detector was operated in butane, pentane and heptane which also served as stopping gases. In this paper, we report on results obtained with fission fragments from a /sup 252/Cf source. We achieved a separation of the light and heavy fragment groups in the interval of gas absorber thickness from about 500 ..mu..g cm/sup 2/ to 1.5 mg cm/sup 2/. The best energy loss resolution was achieved with pentane at E/papprox.=70 V cm/sup 1/ Torr/sup 1/ resulting in delta..delta..E/..delta..Eapprox.=13%. The corresponding shape of the ..delta..E spectrum reproduces correctly the nuclear charge distribution of the fragments. (orig.).

International Nuclear Information System (INIS)

... radiation effects human populations low dose irradiation neoplasms radiation

International Nuclear Information System (INIS)

... defects doped materials germanium infrared radiation monocrystals neutron

International Nuclear Information System (INIS)

... pathological changes patients radiation protection radiotherapy diseases

International Nuclear Information System (INIS)

... compounds polymers polyolefins polyvinyls radiation effects SYNTHESIS.

CERN Document Server

Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy

International Nuclear Information System (INIS)

Carbon-14 was analysed by direct absorption of carbon dioxide on the mixture of organic amine compound and scintillation cocktail then counted by low level liquid scintillation counter. This method can be applied for radiocarbon dating. In this study, the effects of carbon dioxide absorption, and counting efficiency were investigated using various commercial available cocktail. It was found that permafluor V and Ready Gel showed the highest carbon dioxide absorption whereas the Permafluor V showed the highest counting efficiency

International Nuclear Information System (INIS)

We describe the continued development of a portable, real-time neutron spectrometer. The spectrometer is composed of two distinct detector systems: a Helium 3 gas filled proportional counter for the lower neutron energy interval between 20 KeV and 2 MeV and a bulk silicon solid state detector for the higher energy interval between 2 MeV and 500 MeV. Modeling and experimental results with mono-energetic neutron beams are reported.

Energy Technology Data Exchange (ETDEWEB)

A new method of particle identification of heavy ions through the measurement of the Bragg curve centroid and particle energy has been developed using a gas ionization chamber with a resistive anode layer. Z-resolutions comparable to the conventional ..delta..E-E counter telescope could be rather easily attained.

International Nuclear Information System (INIS)

This study mainly concerns medical explorations by radioisotopes. Detectors with medical exams and applications are described. Ionisation chambers, semiconductor detectors and scintillation counters are also presented. Uses of radioisotopes in medicine in vivo and in vitro techniques are explained. Examples of scintiscanning are given like: angiography, nuclear cardiography and thyroid scintiscanning. The importance of the study is to present a panorama of nuclear medicine laboratories -at the time- in hospitals in Lebanon.

Science.gov (United States)

Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4? geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon.

International Nuclear Information System (INIS)

Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4#pi# geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon. (orig.).

International Nuclear Information System (INIS)

A search for tachyons, or other particles detectable by G-M counter tubes or liquid scintillators, arriving during the approximately 100#mu#s immediately preceding extensive air showers (primary energy approximately 10"1"5 eV) has provided no positive evidence for the existence of such particles. (orig.).

International Nuclear Information System (INIS)

Objective: To develop a computerized method of internal dose estimation on radiation protection. Methods: Based on MIRD mathematic model of the organs and by means of the programming language of MS Visual Basic 6.0, a computer program of dose estimation in internal radiation was developed for radiation protection. Results: The computerized method of dose estimation for internal radiation was completed. Conclusions: This computerized method is very convenient for internal radiation dose estimation of several aspects. It can also be used in radiation accident. (authors)

International Nuclear Information System (INIS)

Portuguese Sep-Oct 1996 p. 571 Brazil Campos, Patricia Sao Paulo

Science.gov (United States)

The principles of radionuclide excitation of X-ray fluorescence radiation and its application in

International Nuclear Information System (INIS)

This book gives an overview of the entire field of radiation protection with the subject areas radioactivity, X-rays, UV radiation, laser beams and high-frequency electromagnetic fields. It deals graphically with the most important physical notions, the incidence, origin, properties and biological effects of types of radiation, administrative and practical protection measures and the code of rules governing them. Apart from fundamentals of radiation protection the emphasis on the following: natural radiation exposure, radiation exposure to radon, disaster relief plans in the environment of nuclear plant, the precautionary radiation protection system evolved after Chernobyl, radiation exposure through UV radiation devices, radio, RF communication, radar, microwave ovens and high-voltage transmission ...

ScienceCinema

...spontaneous radiation ...

International Nuclear Information System (INIS)

Short communications only.

International Nuclear Information System (INIS)

Short communication.

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

Short communication.

Science.gov (United States)

Cancer and Tobacco Abuse

International Nuclear Information System (INIS)

The Tissue Equivalent Proportional Counter (TEPC) was developed to monitor low level neutron exposure rates at working stations in a nuclear fuel fabrication facility. It has proven capable of accurately measuring neutron dose rates at levels from 0.1 to 0.2 mrem/hr. It also calculates the Quality Factor which is of importance in locations where the neutron to gamma ratio may vary significantly and irregularily. The system described is computerized to monitor 100 work locations simulationeously and can be expanded to monitor 384 locations. Neutron dose is accumulated on a real time basis and after the proton drop point is established, dose rate can be read out at any time for the dose accumulated over a specified period of time. The current development program which provides reduced system maintenance, lower detection limits, and improved accuracy is discussed along with examples of measurement data and work experience with the current system.

International Nuclear Information System (INIS)

Service water, 100 l each, was collected at an intake of a water treatment plant and at a tap after water was left running for five minutes. The carriers of strontium and cesium were added to water immediately after sampling, and the sample was vigorously stirred and filtered. Then it was passed through a cation exchange column at a rate of 80 ml/min. Strontium and cesium were eluted with hydrochloric acid from the cation exchange column, and separated. After the radiochemical separation, the mounted precipitates were counted for activity using low background beta counters normally for 60 min. Net sample counting rates were corrected for counter efficiency, recovery, self absorption and decay to obtain the content of strontium-90 and cesium-137 radioactivity per sample aliquot. From the results, concentrations of these nuclides in the original sample were calculated. The maximum values obtained were 0.29 pCi/l of Sr-90 in Kyoto in August, 1981, ...

International Nuclear Information System (INIS)

A complete heavy ion identification system in heavy ion reaction studies consists, in general, of: 1) a position sensitive avalanche counter, and 2) ionization chamber to obtain total energy as well as a heavy ion identifier signal (such as the E#DELTA#E signal from a E-#DELTA#E type detector or the height of the Bragg peak that scales as Z of the heavy ion in a Bragg curve ionization chamber). In addition, a time-of-flight information may be needed to resolve the masses of the ions. With this motivation in mind, a composite detector system consisting of a Bragg curve spectroscopy ionization chamber (BCS-IC) and a one dimensional position sensitive parallel grid avalanche counter (XPS-PGAC) has been developed and used successfully at the BARC-TIFR pelletron accelerator facility. The design and performance of this gas detector system are reported. (author). 4 refs., 2 figs.

Energy Technology Data Exchange (ETDEWEB)

A new focal plane detector for an Enge split pole spectrograph has been developed which is able to resolve individual elements and isotopes up to the mass 100 region. It consists of a 60 cm long position sensitive parallel plate avalanche counter backed by a large Bragg curve detector. Compared with other position sensitive focal plane counters the new detector system has a very good time resolution (less than 300 ps) and can be operated at much higher counting rates (up to 25 kHz). The intrinsic resolution of the position detector is less than 1 mm. In addition to the energy and the nuclear charge signal obtained from the Bragg curve detector the angle of incidence into the detector can be measured with an accuracy of better than 1/sup 0/. The detector has already been used in a variety of experiments where good timing, counting rate behavior, and excellent mass resolution over a large energy range were essential.

Energy Technology Data Exchange (ETDEWEB)

This patent describes an energy storage device. It comprises: a working electrode, a counter electrode, electrically isolated from the working electrode; an electrolyte in contact with the working electrode and the counter electrode, and means for collecting electrical current therefrom; the working electrode consisting essentially of an amorphous metal alloy of the formula: A{sub {ital a}}M{sub {ital b}}M{prime}{sub {ital c}}, wherein A is at least one metal selected from the group consisting of Ag, Hg and Pt; M is at least one metal selected from the group consisting of Pb, Cu, Cr, Mo, W, Ni, Al, Co, Fe, Zn, Ru, Cd and Mn; M{prime} is at lest one of the elements selected from the group consisting of Ca, Mg, Ti, Zr, Hf, V, Nb and Ta; and wherein a ranges from about 0.005 to about 0.80; b ranges from 0.05 to about 0.70; and c ranges from about 0.08 to about 0.95.

Energy Technology Data Exchange (ETDEWEB)

We have developed a Bragg curve counter (BCC) equipped with an active cathode to extend the energy acceptance to lower energies than for a conventional BCC to measure differential cross-sections of fragment production reactions induced by tens of MeV protons. The signal from the active cathode providing the timing signal of fragment incidence and the time difference signal between the cathode and anode gives information on the fragment range in the BCC on the basis of electron drift time. Utilization of the range information made possible identification of fragments less than 0.5 MeV/u that is lower than the identification threshold of a conventional BCC technique. After investigations on fundamental properties of a newly constructed BCC using heavy ion beams and alpha-particles, this method was applied successfully to a fragment production measurement for 70 MeV proton-induced reactions on carbon. With this technique, the energy threshold of the BCC was improved ...

International Nuclear Information System (INIS)

This text-book (electronic book - multi-media CD-ROM) constitutes a course-book - author's collection of lectures. It consists of 13 lectures in which the reader acquaints with the basis of radiobiology: Introduction to radiobiology; Physical fundamentals of radiobiology; Radiation of cells; Modification of radiation damage of cells; Reparation of radiation damage of cells; Radiation syndromes and their modification; Radiation injury; Radiation damage of tissues; Effect of radiation on embryo and fetus; Biological effects of incorporated radionuclides; Therapy of acute irradiation sickness; Delayed consequences of irradiation; Radiation oncology and radiotherapy. This course-book may be interesting for students, post-graduate students of chemistry, biology, physics, medicine as well as for teachers, scientific workers ...

Science.gov (United States)

Cervical Cancer; Radiation Toxicity

International Nuclear Information System (INIS)

... beam monitoring betatrons delay circuits errors fluctuations gamma radiation

British Library Electronic Table of Contents (United Kingdom)

This article considers the appeal of cognitive neuroscience research to the general public within the context of the deep puzzles involved in using our minds to understand how our minds work. It offers a few promising examples of findings that illuminate the ways of the mind and reveal these workings to be counter-intuitive with our subjective experience. However, this promise is tempered by the powerful role that perception, attention, and cognition play in how we reason about evidence. It argues that the interplay between what we believe about the nature of our minds and what the findings suggest constitutes a primary challenge in encouraging public understanding of cognitive neuroscience findings.

Energy Technology Data Exchange (ETDEWEB)

Copper alloys are a suitable tubing material for turbine condensers and heat exchangers. Due to problems with corrosions copper alloys increasingly are displaced by high-grade steel and titanium. Blockages and surface formation in the pipes, disturbance of the oxide coating formation, erosion and quality faults with the production are the causes for the corrosion. In the contribution under consideration counter measures are designated for the solution of the problems with corrosions. The application limits for different copper alloys are designated. Recommendations for the optimized operation are given.

Energy Technology Data Exchange (ETDEWEB)

Neutron spectra measured in the FFTF In-Reactor Thimble (IRT) by proton recoil proportional counters, proton recoil emulsions, and passive dosimeters have been evaluated and compared with each other and with three-dimensionl diffusion theory calculated spectra for the purpose of validating the passive dosimeter spectrum adjustment technique. The least squares data adjustment code, FERRET, was used to combine measured reaction rates, calculated spectra, and dosimeter cross sections, resulting in adjusted spectra and cross sections with uncertainties and correlations that properly account for uncertainties and correlations on the input parameters.

Energy Technology Data Exchange (ETDEWEB)

A full scale experiment was carried out to investigate the texture characteristics of the falling water of free falling and slope failing types. According to the increase of Reynolds number, the texture of falling water was classified into three categories for both types: stability of free surface, transition and whole turbulence. In the first category the stability of the free surface was related to the growth of minute disturbance. Surface tension works as a counter, force to the disturbance in free falling water, and gravity in slope falling water. 14 refs., 15 figs., 3 tabs.

Energy Technology Data Exchange (ETDEWEB)

As a counter measure to protect against global warming, the development of CO{sub 2} recovery technology from fossil fuel power plant flue gas has continued. MEA processes are widely used for CO{sub 2} recovery from combustion flue gas in average use etc. However, if we consider power plant scale CO{sub 2} recovery, the biggest theme is the reduction of energy needed to recover CO{sub 2}. The paper focuses on sterically hindered amines and a new absorber packing. Also optimum steam system analysis results are indicated. 1 ref., 16 figs., 3 tabs.

Energy Technology Data Exchange (ETDEWEB)

This book describes the uses, coatings, and fabrication of laser materials. Topics considered include: optical waveguide materials; optical storage materials; holographic recording materials; phase conjunction materials; holographic recording materials; phase conjunction materials; laser crystals; laser glasses; quantum counter materials; thin films and coatings; multilayer dielectric coatings; graded-index surfaces and films; optical materials fabrication; fabrication techniques; fabrication procedures for specific materials.

International Nuclear Information System (INIS)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

International Nuclear Information System (INIS)

On the basis of legally provided area dose measurements and time records of fluoroscopic examinations during the operation, radiation doses to medical personnel and patients are evaluated. Adequate radiation protection measures and a careful behaviour in the operating room keep the radiation exposure to the personnel below the maximum permissible exposure. Taking into account the continuous personnel radiation monitoring and medical supervision, radiation hazards in the operating room can be considered low.

Energy Technology Data Exchange (ETDEWEB)

An experimental investigation on the air/water counter-current two-phase flow in a horizontal rectangular channel connected to an inclined riser has been conducted. This test-section representing a model of the hot leg of a pressurized water reactor is mounted between two separators in a pressurized experimental vessel. The cross-section and length of the horizontal part of the test-section are (0.25 m x 0.05 m) and 2.59 m, respectively, whereas the inclination angle of the riser is 50 deg. The flow was captured by a high-speed camera in the bended region of the hot leg, delivering a detailed view of the stratified interface as well as of dispersed structures like bubbles and droplets. Countercurrent flow limitation (CCFL), or the onset of flooding, was found by analyzing the water levels measured in the separators. The counter-current flow limitation is defined as the maximum air mass flow rate at which the discharged water mass flow rate is ...

Energy Technology Data Exchange (ETDEWEB)

Atomization of liquid fuel in aircraft engines requires application of airblast atomizers, where the kerosene is supplied into the shear layer between two swirling airstreams. The transfer of this functional principle towards gaseous fuel, as illustrated in Fig. 1, yielded a strong influence of the swirl arrangement of the airflows on flame stability and homogeneity of the fuel/air-mixture. Compared to the co-swirl configuration the flow field of the counter-swirl arrangement exhibits a marked increase of the mass flow recirculated in the internal recirculation zone and a reduction of its length in axial direction. This is attributed to the faster decay of tangential velocity maxima in case of counter-rotating airflows. This generates a stronger positive axial pressure gradient dp/dx, thus enhancing the internal recirculation zone. Analysis of local turbulence quantities yields a restriction of turbulent exchange to smaller radial sections and ...

International Nuclear Information System (INIS)

The most propagated mechanisms of stimulated radiation of electron beam such as Cherenkov one-particle and collective effects, ondulator and magnetic bremsshrahlung radiations, Doppler anomalous effect, Thompson and Raman scattering and radiation are discussed. Relation of spontaneous radiation mechanisms of individual electron and stimulated radiation effects in electron beams has been elucidated, grounds of linear electrodynamics of radiative beam instabilities are stated, and main mechanisms of their nonlinear stabilization are elucidated as well. Various simulated processes in electron beams are considered from the unique point of view using a simple mathematical apparatus and such physical laws as conservation and Newton laws.

British Library Electronic Table of Contents (United Kingdom)

Abstract Satellite measurements and numerical forecast model reanalysis data are used to compute an updated estimate of the cloud radiative effect on the global multi-annual mean radiative energy budget of the atmosphere and surface. The cloud radiative cooling effect through reflection of short wave radiation dominates over the long wave heating effect, resulting in a net cooling of the climate system of - 21 Wm-2. The short wave radiative effect of cloud is primarily manifest as a reduction in the solar radiation absorbed at the surface of - 53 Wm-2. Clouds impact long wave radiation by heating the moist tropical atmosphere (up to around 40 Wm-2 for global annual means) while enhancing the radiative cooling of the atmosphere over other regions, in particular higher latitudes and sub-trop...

Science.gov (United States)

The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents. PMID:21809627

Energy Technology Data Exchange (ETDEWEB)

The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation.

International Nuclear Information System (INIS)

The radiation burden of the people of the GDR in relation to biomedical radiography altogether as well as organ doses, gonad doses and genetically significant doses in detail are outlined. The concepts of radiation protection and standards of radiographic examination are demonstrated. Possibilities of influencing radiation exposure by scientifically based indication of X-ray examination, application of new and improvement of usual examination techniques are discussed with regard to quality assurance and control. Proposals concerning the reduction of radiation exposure of the GDR population are presented.

International Nuclear Information System (INIS)

Correlation characteristics of quantum noise on the shadow radiation image (RI) of the object under nondestructive testing are studied. Mathematical model of RI occasional distortions is derived. The model takes into account the parameters of object under testing and of radiation beam by radiation quanta flux density. The results obtained can be used as a component in the process of investigation of various radiation testing systems

Science.gov (United States)

A new type of radiation which occurs when particles are accelerated in the field of a longitudinal wave and in a transverse magnetic field is studied. The characteristics of such spontaneous radiation are obtained, and the influence of collective effects on the radiation is analyzed. The application of the findings to the theory of free electron lasers is discussed. 8 references.

UK PubMed Central (United Kingdom)

Objectives To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental,...Full Text Available

International Nuclear Information System (INIS)

Exact anatomic knowledge about the location of the gonads and the application of corresponding measures of radiation protection are the preconditions for an efficient reduction of the danger of a possible genetic damage as a result of radiation exposition during X-ray examination of the hip joint of newborns. (VJ).

Science.gov (United States)

Analytical method of theoretical simulation of collective hydrodynamic instabilities of intensive flows of discrete radiators, interacting with each other only through the coherent fields of their spontaneous radiation in corresponding media was suggested...

International Nuclear Information System (INIS)

The different radiation loads caused by natural and artificial radionuclides are compared in this paper. This examples will serve to illustrate that the problem of population exposure to radiation can only be solved in consideration of all components and to show which effects of the radiation from natural sources are of special importance in this connexion. (orig./AK).

International Nuclear Information System (INIS)

An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate

Science.gov (United States)

Mar 1, 2011 ... Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation ...

Energy Technology Data Exchange (ETDEWEB)

The report gives general principles of treatment and care of casualties caused by radiation accidents or nuclear explosions.

International Nuclear Information System (INIS)

... bollworm fertility gamma radiation genetic radiation effects life span mating

Science.gov (United States)

... Solar Cell Radiation Respinnse Near the Interface o~f fliffprerv- ... 5 4. CALCUTl-ATED SOLAR CELL RLSPONSE FOR VARIOUS BASE MATERIALS ...

Wastenet

...References | Radiation Protection | US EPA This page provides links to the reference material on EPA's Radiation Protection Web site. U.S. EPA/...OAR/ORIA/Radiation Protection Division Jump to main content. Radiation Protection Contact Us Search: All EPA This Area You are here: EPA Home ... Radiation Protection References PageName Technical Users General Public Reporters Librarians Students/Teachers PROGRAMS TOPICS REFERENCES References The Reference Section provides general material that support the ...other sections of EPA's Radiation Protection Web site. You will find links within the information to related pages throughout the Radiation Protection , EPA ...

Energy Technology Data Exchange (ETDEWEB)

The fundamental product of tetracycline hydrochlorine gamma radiolysis was separated in its solid state. From the results of spectroscopic studies it has been established that it is des-N,N-dimethylaminotetracycline.

Science.gov (United States)

the probability of its spontaneous radiation de-excitation increases. ... consider spontaneous radiation transitions. We will examine the ...

International Nuclear Information System (INIS)

Turbulent premixed methane-air combustion in a cylindrical chamber is numerically simulated considering radiation effect. Reaction rates are considered as minimum rates between Arrhenius rates and eddy break up rates. A five step reduced mechanism is used. Turbulent modeling is done via standard k-? model imposed by empirical inlet boundary conditions. Source terms of energy equation consist of reaction rates and radiation effects. The discrete ordinate method (DOM) is employed to solve the radiative transfer equation (RTE) and the weighted sum of gray gas model (WSGGM) is imposed to consider radiation effect of non-gray gases. The results indicate that in the case of turbulent combusting flows, the effect of radiation of gases can affect the temperature and species concentrations. The numerical results obtained considering radiation effect are closer to the ...

Science.gov (United States)

... iFfficiency-en- enhanced spontaneous radiation at the free-electron- ... as enhanced spontaneous radiation at the free-electron-laser wavelength. ...

International Nuclear Information System (INIS)

When energetic bunches of electrons traverse an undulator field, they can spontaneously emit radiation both coherently and incoherently. Although it has generally been assumed that undulator radiation is incoherent at wavelengths short compared to the longitudinal size of the electron bunch, several recent observations have proved this assumption false. Furthermore, the appearance of coherent radiation is often accompanied by a significant increase in radiated power. Here we report observations of strongly enhanced coherent spontaneous radiation together with direct measurements, using transition radiation techniques, of the electron distributions responsible for the coherent emission. We also report demonstrated enhancements in the predicted spontaneous radiated power by as much as 6x10"4 using electron bunch compression. copyright 1996 ...

International Nuclear Information System (INIS)

General mechanisms of radiation damage to biomolecules was studied by using substituted pyrimidines, particularly barbituric acid derivatives.

Science.gov (United States)

... Except for isolated radiation accidents over the ensuing years, little practical experience has been gained in the treatment of thermal injuries ...

UK PubMed Central (United Kingdom)

PurposeTo evaluate four planning techniques for stereotactic body radiation therapy (SBRT) in lung tumors.Methods...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The superconducting Tevatron accelerator at Fermi National Accelerator Laboratory (Fermilab) has surpassed twenty years of operation. The Tevatron is still the highest energy particle accelerator in the world and will remain so until the commissioning of the LHC in Europe later this decade. The Tevatron has operated in a Fixed Target mode, accelerating a proton beam into stationary targets/detectors, as well as a Colliding Beam mode, continuously colliding counter rotating beams of protons and antiprotons. Upon completion, the Tevatron cryogenic system became the world's largest helium refrigeration system. In 1993, the Tevatron cryogenic system was given the designation of International Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers. The operational history, experiences and statistics of the Tevatron, with an emphasis on the cryogenic system, is presented. Improvements, upgrades and current challenges of the ...

Energy Technology Data Exchange (ETDEWEB)

This paper discusses the application of a Computational Fluid Dynamics (CFD) code (FLUENT) to predict temperature and velocity profiles, and particle trajectories in an industrial fired by a low NO{sub x} pulverized coal swirl burner. The predictions of the code were compared to experimental measurements of gas temperature, particle size distribution, and particle velocities. The diagnostics employed were a suction pyrometer and a Particle Counter Sizer Velocimeter Probe (PCSV-P). Good agreement was found between the temperature predictions and the measurements. In situ particle size distributions were predicted accurately using the Baum and Street model with a swelling factor of zero. The numerical modeling indicated that the Type II flow issued from the burner could be transformed into Type III flow, by eliminating swirl from the primary air stream, which provided the preferred particle trajectories and increased the combustion efficiency.

International Nuclear Information System (INIS)

Water chemistry of nuclear power plants has played an important role in reduction of personnel doses, structural materials and fuel integrity assurance, and reduction of radioactive wastes production. Further contributions are requested for advanced utilization of the LWR, advanced fuels and aging management of plants. Since water chemistry has an effect on all structure and materials immersed and at the same time affected by them, the optimum control not sticking to specific issues and covering the whole plant is required for these requests. Taking account of roles and activities of the industry, governmental institutes and academia, road maps on research and development plans for water chemistry were compiled into identified eleven items with targets and counter measures taken, such as common basic technologies, dose reduction, SCC mitigation, fuel cans corrosion/hydrogen absorption mitigation, condition based maintenance and flow accelerated corrosion ...

Energy Technology Data Exchange (ETDEWEB)

The crystal structure of Ca{sub 2}RuD{sub 6} has been determined by neutron powder diffraction: space group Fm3m, K{sub 2}PtCl{sub 6} structure, as found for other hexahydride salts of group 8 metals with alkaline earth or lanthanide counter ions. No structural phase transition was observed between 340 K and 50 K. The deuterium nuclear quadrupole coupling constant, 54.7 kHz, leads to an ionic character of the Ru-D bond of 76%. The known trends in the behaviour of A{sub 2}MH{sub 6} salts are interpreted in terms of the ionization energies of the cation and the central metal atom.

CERN Document Server

Research shows that comment spamming (comments which are unsolicited, unrelated, abusive, hateful, commercial advertisements etc) in online discussion forums has become a common phenomenon in Web 2.0 applications and there is a strong need to counter or combat comment spamming. We present a method to automatically detect comment spammer in YouTube (largest and a popular video sharing website) forums. The proposed technique is based on mining comment activity log of a user and extracting patterns (such as time interval between subsequent comments, presence of exactly same comment across multiple unrelated videos) indicating spam behavior. We perform empirical analysis on data crawled from YouTube and demonstrate that the proposed method is effective for the task of comment spammer detection.

British Library Electronic Table of Contents (United Kingdom)

Urban heritage areas throughout the world have experienced cycles of neglect and upgrade that were at times intentional and at other times due to economic difficulties or an unbalanced ideological focus on technological, social or political developments. Modernism of the early and mid-1900s was clearly against keeping heritage areas as they were perceived to hinder future developments. Postmodernist thinking afterwards was more sympathetic to heritage as a means of countering the 'placelessness' of the modern city. Global appreciation of urban heritage and the world's cultural diversity at the end of the century made the occurrence of 'physical neglect' cycles very unlikely in the future. This research paper takes the stand that urban planners and designers face cycles of higher or lower u...

International Nuclear Information System (INIS)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alphy source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm diameter plexiglass cell can be extended to at least 50 cm length without difficulty from insufficient pulse ...

British Library Electronic Table of Contents (United Kingdom)

Virtualized infrastructure providers demand new methods to increase the accuracy of the accounting models used to charge their customers. Future data centers will be composed of many-core systems that will host a large number of virtual machines (VMs) each. While resource utilization accounting can be achieved with existing system tools, energy accounting is a complex task when per-VM granularity is the goal. In this paper, we propose a methodology that brings new opportunities to energy accounting by adding an unprecedented degree of accuracy on the per-VM measurements. We present a system - which leverages CPU and memory power models based in performance monitoring counters (PMCs) - to perform energy accounting in virtualized systems. The contribution of this paper is threefold. First, w...

British Library Electronic Table of Contents (United Kingdom)

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up inc...

Energy Technology Data Exchange (ETDEWEB)

Normal butylamine compounds are studied as salt-free wash reagents for degraded solvent used in PUREX process in spent fuel reprocessing. The solvent wash tests were carried out with two types of butylamine compounds, n-butylamine oxalate and n-butylamine bicarbonate, by counter-current mode using a small size mixer-settler composed of two 4-stage wash steps. Di-n-butyl phosphoric acid (HDBP), the main degradation product from TBP, was removed from real degraded solvent with decontamination factor of 2.5 {approx} 7.9. The study on electrolytic decomposition of butylamine compounds was also conducted for waste treatment.

International Nuclear Information System (INIS)

Researchers at the Laboratory of Nuclear Microanalysis in Besancon (France) are developing and improving radon measurements in order to detect and analyse, more precisely radon emanation anomalies in both fields of Earth Sciences and Radioprotection. In order to characterize radon emanation, two complementary techniques are developed; continuous measurement through a portable proportional counter and passive measurements by nuclear track detectors for both fieldwork and laboratory analysis. A mathematical model is being devised to interpret the nuclear track detector response. This model is performed according to the device characteristics: type of detectors, shape and size of cells and whether a membrane is used or not. In addition to the theoritical study, experimental radon concentration measurements will be reported. (author).

CERN Document Server

We consider 4-dimensional space-times which are asymptotically flat at spatial infinity and show that, in the first order framework, action principle is well-defined \\emph{without the need of infinite counter terms.} It naturally leads to a covariant phase space in which the Hamiltonians generating asymptotic symmetries provide the total energy-momentum and angular momentum of the space-time. We address the subtle but important problems that arise because of logarithmic translations and super-translations both in the Langrangian and Hamiltonian frameworks. As a forthcoming paper will show, the treatment of higher dimensions is considerably simpler. Our first order framework also suggests a new direction for generalizing the spectral action of non-commutative geometry.

Energy Technology Data Exchange (ETDEWEB)

Linear-optical passive (LOP) devices and photon counters are sufficient to implement universal quantum computation with single photons, and particular schemes have already been proposed. In this paper we discuss the link between the algebraic structure of LOP transformations and quantum computing. We first show how to decompose the Fock space of N optical modes in finite-dimensional subspaces that are suitable for encoding strings of qubits and invariant under LOP transformations (these subspaces are related to the spaces of irreducible unitary representations of U (N). Next we show how to design in algorithmic fashion LOP circuits which implement any quantum circuit deterministically. We also present some simple examples, such as the circuits implementing a cNOT gate and a Bell state generator/analyser.

British Library Electronic Table of Contents (United Kingdom)

The Baobab tree (Adansonia digitata L.) is a key multipurpose species for the African region. In the recent years there has been an extended commercial interest for different A. digitata products. As a spectacular African key species there has been a growing interest from NGO?s and various research groups. A research group, focussing on the following countries Burkina Faso, Mali and Niger, has participated in a concerted research action with cross counter disciplinary cooperation between plant physiology, population genetics, tree breeding, food science, and socioeconomics. This paper presents a review and the way knowledge gaps are being addressed using the above mentioned approach. The overall work was initiated in 2005?2006 when a large collection of A. digitata seeds was carried out in...

British Library Electronic Table of Contents (United Kingdom)

An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of par...

International Nuclear Information System (INIS)

A large area Bragg curve spectroscopy (BCS) detector and a position sensitive parallel grid avalanche counter have been developed to study heavy ion reactions, such as inelastic excitations and few nucleon transfer reactions near the Coulomb barrier. Reasonably good resolutions have been achieved for energy, atomic number and angle. A theoretical investigation on the mass dependence of the Bragg peak signal from the BCS detector, shows that there is a negligible mass dependence related to the geometry of the detector. The mass number of the heavy ions which cannot be obtained by the above method, has been identified by detecting the corresponding characteristic gamma rays from the product nuclei with two large solid angle gamma ray detectors. (orig.).

International Nuclear Information System (INIS)

... v. 1267(1) RADIATION CHEMISTRY, RADIOCHEMISTRY AND NUCLEAR

Energy Technology Data Exchange (ETDEWEB)

The book is divided into two approximately equal parts. The first four chapters are relatively lengthy and cover the basic principles of radiation biology, carcinogenesis and therapy, along with a brief introduction to radiological physics to orient the reader without background in this specialized related discipline. The remainder consists of twenty-four relatively brief chapters, each covering the radiation biology of a specific organ, tissue, or systems tissues, with emphasis on the tumorigenic and tumoricidal action of ionizing radiations.

Energy Technology Data Exchange (ETDEWEB)

Short communication. 5 refs., 2 figs.

International Nuclear Information System (INIS)

... VDPEAZ (Bonn 2010 issue) NUCLEAR PHYSICS AND RADIATION PHYSICS

KoreaScience (Korea)

Full Text Available

Science.gov (United States)

Not Available

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

Disclosed herein is a radiation detector providing for the in situ automatic sampling of fluids containing substances emitting radiation, especially Cerenkov radiation. The detector permits sampling within well casings and is self-purging such that no additional provisions must be established for the storage and disposal of contaminated fluids.

Energy Technology Data Exchange (ETDEWEB)

A brief guide to training and equipment needed to effectively manage victims of radiation accidents. (DT)

Science.gov (United States)

Not Available

International Nuclear Information System (INIS)

A study is made of the mechanical properties of vanadium irradiated with fast neutrons up to dose 8.6.10"-"4 dpa, as a function of the temperature of post-radiation annealing. The radiation-annealing hardening (RAH) effect is observed at 300"oC, in agreement with previous studies. It is established for the first time that RAH is accompanied by fall in ductility. A phenomenological model is described which explains the dependence of RAH on radiation dose and temperature, as well as on the content of chemically active alloying impurities. (author).

International Nuclear Information System (INIS)

Japanese (Mar 1974). Japan Mabuchi, Toshio Kuwada, Hikaru . Kagawa Univ.,

International Nuclear Information System (INIS)

Short communication.

Science.gov (United States)

... biologically important compounds is sharply lowered with passage of the solutions to the cell an organ, where their sensitivity ...

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

... radiation parity photonuclear reactions polarized beams resonance

Energy Technology Data Exchange (ETDEWEB)

A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array.

International Nuclear Information System (INIS)

(1985). USSR Nedavnij, OI Tomskij Politekhnicheskij Inst. (USSR).

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

... electron spin resonance gamma radiation lipids lyophilization lysozyme radicals

International Nuclear Information System (INIS)

Due to the intensity and vast number of subjects, this Bremen experts' discussion, too, could discuss only part of the problem of the possibilitiy to quantify the radiation hazard. One preliminary result is that there is no scientific proof of the harmlessness of radiation exposure during normal operation of a nuclear power plant, either within the plant or in its vicinity. Other results are that some important questions can not be answered yet, and that there are important hints on the dangers even of low radiation doses. (GL).

International Nuclear Information System (INIS)

Short note.

Science.gov (United States)

PMID:20602289

Energy Technology Data Exchange (ETDEWEB)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of {sup 6}Li and {sup 7}Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of {sup 6}Li and {sup 7}Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

International Nuclear Information System (INIS)

The total radiation rate, angular distribution of the emitted energy and photon correlations of the cooperative spontaneous radiation from two atoms with different resonance frequencies and spontaneous decay rates are calculated. Contrary to the case of two identical atoms oscillations appear in the total radiation rate and the spatial distribution of the total number of emitted photons differs from the single-atom radiation pattern. The effect of the dipole-dipole near-field interaction on the time evolution of the atomic system is discussed. (author).

UK PubMed Central (United Kingdom)

BackgroundTo compare two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the setting of hypofractionated...Full Text Available

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

Short communication.

International Nuclear Information System (INIS)

Published in summary form only.

Science.gov (United States)

radionuclide X-ray fluorescence analysis: the resolving power of the ... The radiation detectors used in radionuclide X-ray fluorescence ...

CERN Document Server

We formulate a complete theory of Edge Radiation based on a novel method relying on Fourier Optics techniques. Similar types of radiation like Transition Undulator Radiation are addressed in the framework of the same formalism. Special attention is payed in discussing the validity of approximations upon which the theory is built. Our study makes consistent use of both similarity techniques and comparisons with numerical results from simulation. We discuss both near and far zone. Physical understanding of many asymptotes is discussed. Based on the solution of the field equation with a tensor Green's function technique, we also discuss an analytical model to describe the presence of a vacuum chamber. In particular, explicit calculations for a circular vacuum chamber are reported. Finally, we consider the use of Edge Radiation as a tool for electron beam diagnostics. We discuss Coherent Edge ...

International Nuclear Information System (INIS)

The stages of processes leading to radiation damage are studied, as well as, the direct and indirect mechanics of its production. The radiation effects on nucleic acid and protein macro moleculas are treated. The physical and chemical factors that modify radiosensibility are analysed, in particular the oxygen effects, the sensibilization by analogues of nitrogen bases, post-effects, chemical protection and inherent cell factors. Consideration is given to restoration processes by excision of injured fragments, the bloching of the excision restoration processes, the restoration of lesions caused by ionizing radiations and to the restoration by genetic recombination. Referring to somatic effects of radiation, the early ones and the acute syndrome of radiation are discussed. The difference of radiosensibility observed in mammalian cells and main observable alterations in tissues and ...

Energy Technology Data Exchange (ETDEWEB)

A zinc-air battery using zinc regeneration electrolysis with propanol oxidation as a counter electrode reaction is reported in this paper. It possesses functions of both zincate reduction and electrochemical preparation, showing the potential for increasing the electronic energy utilization. Charge/discharge tests and scanning electron microscopy (SEM) micrographs reveal that when a nickel sheet plated with the high-H{sub 2}-overpotential metal, cadmium, was used as the negative substrate electrode, the dendritic formation and hydrogen evolution are suppressed effectively, and granular zinc deposits become larger but relatively dense with the increase of charge time. The performance of batteries is favorable even if the charge time is as long as 5 h at the current density of 20 mA cm{sup -2}. Better discharge performance is achieved using a 'cavity-opening' configuration for the discharge cell rather than a 'gas-introducing' ...

International Nuclear Information System (INIS)

We measured neutron time-of-flight spectra from 90 MeV protons and 140 MeV alpha particles bombarding thin targets of Al, Ni, Zr, and Bi at laboratory angles between 20_0 and 135_0. The low-energy (5 to 45 MeV) portions of the spectra were measured with 5 cm diameter by 5 cm deep NE-213 counters at 1 m flight paths with n-#betta# pulse-shape discrimination. The high-energy (35 to 150 MeV) portions of the spectra were measured with 12.7 cm diameter by 10.2 cm deep NE-102 counters at flight paths of 2.0 to 5.0 m. The proton-induced measured neutron spectra reveal three distinct energy regions: a low-energy evaporation region, a high-energy region dominated by the quasifree scattering process, and an intermediate-energy region dominated by multistep, preequilibrium processes. In the latter two regions, the spectra show strong angular dependence. The alpha-particle induced neutron spectra show these same distinct energy regions plus an exponential ...

International Nuclear Information System (INIS)

In 65 adult rabbits of both sexes (2.5 to 6 kg) the following salvaging procedures were performed after simulated trauma: (1) Continuous suture line; (2) closure with fibrin sealant after temporary clamping; (3) hemisplenectomy with omental wrap; (4) suture fixation of fragments and slices of spleen tissue to the peritoneum; (5) suture fixation of spleen fragments to the omentum; (6) extraperitoneal subcutaneous transposition of spleen cubes. In addition, the likelihood of spontaneous splenosis was examined in a preliminary study involving 5 animals by introducing unattached spleen meal and fragments. Scanning was repeated 4 to 12 weeks postoperatively. The functional competence of minor parenchymal islands was also investigated with well counter measurements of organ and muscle tissue homogenates. Spontaneous splenosis after abdominal injuries was not found to be the rule. Salvaging procedures at the natural vascular hilus by sutures, fibrin sealant and ...

Science.gov (United States)

The LLNL Chemical & Biological National Security Program (CBNP) provides science, technology and integrated systems for chemical and biological security. Our approach is to develop and field advanced strategies that dramatically improve the nation's capabilities to prevent, prepare for, detect, and respond to terrorist use of chemical or biological weapons. Recent events show the importance of civilian defense against terrorism. The 1995 nerve gas attack in Tokyo's subway served to catalyze and focus the early LLNL program on civilian counter terrorism. In the same year, LLNL began CBNP using Laboratory-Directed R&D investments and a focus on biodetection. The Nunn-Lugar-Domenici Defense Against Weapons of Mass Destruction Act, passed in 1996, initiated a number of U.S. nonproliferation and counter-terrorism programs including the DOE (now NNSA) Chemical and Biological Nonproliferation Program (also known as CBNP). In ...

International Nuclear Information System (INIS)

Scattered radiation generated in patient and imaging system has to be considered when quality-assurance tests involve dose detection or image-quality estimations. Measurement of automatic-exposure control dose can be altered by backscattering from intensifying screens of more than 10% and the equipment transmission factor can be overestimated up to a factor of 10 when only primary radiation is used. The sensitivity of intensifying screens depends on the angle of incidence of the radiation and so primary and scattered radiation are detected differently. The quality-control aspects of anti-scatter grids are discussed. (author).

International Nuclear Information System (INIS)

The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation. (author).

Energy Technology Data Exchange (ETDEWEB)

The authors give a survey of the somatic radiation risk in X-ray diagnostics. A somatic dose index is calculated for different examination methods containing the organ doses to the red bone marrow, the lung, the female breast, and the thyroid gland and evaluating their somatic significance. If this somatic dose index by which the individual radiation risk is described, is multiplied by the examination frequencies per year in the German Federal Republic, one gets the somatically significant dose index, which is a measure of the collective somatic radiation risk. In this sense, mammography has the highest, and dental radiography the lowest collective radiation risk.

Energy Technology Data Exchange (ETDEWEB)

The diffusion coefficient of particles in radioactive gases has been calculated with account of random wandering of aerosols (occurrence of local fields affecting the particles; recoils accompanying radiation emitted by particles, etc.). To determine the diffusion coefficient, the method of Fokker-Planck equation derivation was used. A formula is presented for calculating the radiation-stimulated diffusion coefficient. A linear growth of the diffusion coefficient with radioactivity is noted according to the formula, the diffusion coefficient is mainly determined by the field in the radiation damage region. The aerosol radioactivity may result in a more rapid deposition of aerosols in the pipelines and aerosol purification systems. The diffusion rate grows not only in the presence of intrinsic radioactivity but in case of external radiation exposure as well.

Energy Technology Data Exchange (ETDEWEB)

RADSOLVER is a computer program which calculates the radiation energy transport in cavity type receivers having an arbitrary number of apertures through which collimated beams of solar radiation enter. In contrast to the common assumption of gray (or semi-gray) surfaces used in the modeling of radiation transport, RADSOLVER accounts for the wavelength-dependence of emission, absorption and reflection with a band model of the radiative properties. It is intended that this report serve both as an instruction manual for the use of the RADSOLVER code and a vehicle for presenting the underlying theory. Illustrative examples along with input and output are presented.

International Nuclear Information System (INIS)

In radiation risk assessment it must be differentiated between somatic and genetic effect on the one hand as well as between stochastic and non-stochastic effect on the other. According to definitions of the ICRP report 26 the limit for the dose equivalent of all tissues prevents non-stochastic radiation effects. With stochastic radiation effects probably exist no threshold doses; therefore the ALARA principle must be applied concerning radiation protection. The individual risk by stochastic radiation effects in its linear, linear-quadratic and quadratic extrapolations, respectively, is discussed in detail. The effective stochastic dose equivalent (H/sub eff/) as well as collective dose and collective damage are outlined.

Energy Technology Data Exchange (ETDEWEB)

Delayed cerebral necroses after irradiation are to be divided into hemispheric and midline lesions, as they differ from each other in several aspects. Apart from the symptoms, they are differing in the duration of latency, in the course and prognosis, and also with regard to morphology. Though there is no doubt that radiation tolerance of cerebral midline structures is relatively limited, on biological grounds, evidence of a difference between the tolerated doses could not be given from the existent inhomogeneous radiation data, with the help of the NSD-concept. Radiation planning for the region of the head, nevertheless, carefully should avoid in every case to involve the structures of the cerebral midline.

International Nuclear Information System (INIS)

Investigations were carried out of radiation level around Daya Bay for three times since the construction and operation Daya bay Nuclear Power Station and Lingao Nuclear Power Station in Guangdong province in the period of 1988 to 2000. As shown by the investigation, the radiation levels both in the field and indoors remains unchanged by and large but slightly higher than before on the roads. Also this paper gives the analysis of variations in radiation levels form site to site and from time to time. It was shown that, for environmental ? radiation levels measurements, typical measuring sites have significant impact on the meaning results. (authors)

Science.gov (United States)

Spontaneous radiation emitted from relativistic electrons undergoing betatron motion in a plasma-focusing channel is analyzed, and applications to plasma wake-field accelerator experiments and to the ion-channel laser (ICL) are discussed. Important similarities and differences between a free electron laser (FEL) and an ICL are delineated. It is shown that the frequency of spontaneous radiation is a strong function of the betatron strength parameter a(beta), which plays a role similar to that of the wiggler strength parameter in a conventional FEL. For a(beta) > or approximately 1, radiation is emitted in numerous harmonics. Furthermore, a(beta) is proportional to the amplitude of the betatron orbit, which varies for every electron in the beam. The radiation spectrum emitted from an electron beam is calculated by averaging the single-electron spectrum over the electron distribution. This leads to a ...

International Nuclear Information System (INIS)

The incidence of hilar cholangiocarcinoma is very rare worldwide. Radical resection is the only prognostic factor for long survival in patients with hilar cholangiocarcinoma. Postoperative radiation therapy can improve local control and survival rates for patients with palliative resection, but it remains controversial in patients with radical resection. Biliary drainage can effectively release bile duct obstruction for the majority of patients with locally advanced disease, and may even prolong survival when combined with radiation therapy. Radiation therapy includes extrernal beam therapy alone, external beam therapy with intraluminal brachytheapy and new radiation technique, such as three dimentional conformal therapy and intensity modulated radiation therapy. The propective randomized clinical study is needed for further investigation in the role of combined modality therapy ...

International Nuclear Information System (INIS)

Microprocessor based ''smart'' pressure, level, and flow transmitters were tested to determine the radiation hardness of this class of electronic instrumentation for use in reactor building applications. Commercial grade Complementary Metal Oxide Semiconductor (CMOS) integrated circuits used in these transmitters were found to fail at total gamma dose levels between 2500 and 10,000 rad. This results in an unacceptably short lifetime in many reactor building radiation environments. Radiation hardened integrated circuits can, in general, provide satisfactory service life for normal reactor operations when not restricted to the extremely low power budget imposed by standard 4--20 mA two-wire instrument loops. The design of these circuits will require attention to vendor radiation hardness specifications, dose rates, process control with respect to radiation hardness factors, and ...

International Nuclear Information System (INIS)

Presented are the investigation results of electrophysical and physico-mechanical properties of KLF-20, Viksint U-4-21, Viksint KT-73, UF-7-21, KG-184, KL-4, KL-16SE-305, VIAT-1 and PPK-21 sealants, irradiated with sources of continuous and pulse #gamma#-radiation, as well as pulse #gamma#-neutron radiation. It is shown that electrophysical and physico-mechanical properties of sealants after irradiation by continuous #gamma#-radiation up to 10"6 doses and pulse gamma-neutron radiation with neutron fluence of 10"1"3 neutron/cm"2 and #gamma#-radiation dose of 10"4R do not practically change. Electric conductivity and tangent of the angle of dielectric losses increase in the process of irradiation. Electric conductivity depends on irradiation type, is proportional to dose rate and does not depend on temperature and pulse duration.

Energy Technology Data Exchange (ETDEWEB)

Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

International Nuclear Information System (INIS)

In radiation processing of food, the product often has to be prepackaged to prevent microbial recontamination during and after irradiation. The packaging material is exposed to radiation during radiation processing and radiation stability is a key consideration in the selection of packaging materials. The effects of ionizing radiation on many food packaging materials at the dose levels recommended for food precessing can be minimized by selecting appropriate radiation resistant materials. It is important to select materials in which chemicals formed as a result of the radiation treatment do not migrate and interact with the food, affecting its organoleptic and toxicological aspects. It is also important to select materials in which the physical properties are not altered to the extent they cannot resist damage during commercial production, ...

Science.gov (United States)

The somatically significant dose index can be considered as a measure for the somatic radiation risk to which the population is exposed. Figures are stated for conventional tomography of the skull and thorax. These are compared with the corresponding data for other x-ray examinations, especially computerised tomography. PMID:7134769

International Nuclear Information System (INIS)

A brief description of the physical process of dose enhancement effects produced by X-ray radiation on materials is given, with emphasis on the influence on electronic devices. The damages caused by X-ray radiation dose enhancement is more serious than that of #gamma#-ray with higher energy.

UK PubMed Central (United Kingdom)

PurposeWe conducted a comparative study of Clinical Target Volume (CTV) definition of pelvic lymph nodes by multiple GU radiation oncologists looking at the levels...Full Text Available

CERN Document Server

We show that, in addition to radiation travelling at the speed of light, QED theory predicts a second type of radiation with an infinite velocity. We also show that charge, as it appears in the Dirac equation, may have a triune nature.

UK PubMed Central (United Kingdom)

To capitalize on the response of tumor cells to ionizing radiation, we developed a controlled-release nanoparticle drug delivery system using a targeting peptide that recognizes a radiation-induced...Full Text Available

International Nuclear Information System (INIS)

The somatically significant dose index can be considered as a measure for the somatic radiation risk to which the population is exposed. Figures are stated for conventional tomography of the skull and thorax. These are compared with the corresponding data for other X-ray examinations, especially computerised tomography. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This paper describes a radiation shield verification survey of a large hot cell at the Fast Flux Test Facility (FFTF). The following aspects of the shield test are discussed: description of the FFTF; description of the hot cell; the test procedures; radiation protection, and the test results.

Energy Technology Data Exchange (ETDEWEB)

The effect of adriamycin in combination with radiation on the skin reactions of mouse feet has been examined under a variety of experimental conditions including: (a) hyperthermic treatment of the foot immediately following adriamycin administration, with the former given either just before or just after x irradiation, and (b) fractionated treatments of drug and radiation in a variety of sequences over an 18-day period. In the case of the most severe hyperthermic treatment, no increased radiation reactions were observed in the presence of adriamycin. However, in the case of the less severe hyperthermic treatment a small but significant increase in skin reactions was observed. In the study of fractionated drug and radiation treatments, an enhancement of reaction in those animals receiving combined modality treatment over those receiving radiation alone was seen in those groups where ...

International Nuclear Information System (INIS)

The radiation method has been employed for the modification of the surface of vascular prostheses by means of acrylamide. As a result of the treatment, the tightness of the prosthesis walls was improved as well as an increase of surface hydrophilicity. Upon autoclaving, stable binding of polyacrylamide to prostheses is achieved. (author).

International Nuclear Information System (INIS)

Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives and is highly efficient. Its dose requirement is moderate. Radiation doses of 3-10 kGy (0.3-1 mrad) have proved sufficient to reduce the viable counts to a satisfactory level. Ionising radiations do not cause any significant rise in temperature. The flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for satisfactory decontamination, and radiation obviates the chemical residue problem. The microflora surviving radiation decontamination of dry ingredients are more susceptible to subsequent antimicrobial treatments. Recontamination can be prevented as the product can be ...

UK PubMed Central (United Kingdom)

Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe aim of this study was to compare and to validate different dose calculation algorithms for the use in radiation therapy of small lung lesions and to optimize the treatment...Full Text Available

Science.gov (United States)

Spontaneous radiation by an atom in a Rydberg state is inhibited by use of parallel conducting planes to eliminate the vacuum modes at the transition frequency. Spontaneous radiation emission is observed to turn off abruptly at the cutoff frequency of the waveguidelike structure, and the natural lifetime is measured to increase by a factor of at least 20.

UK PubMed Central (United Kingdom)

Purpose: Understanding the kinetics of tumor growth∕shrinkage represents a critical step in quantitative assessment of therapeutics and realization of adaptive radiation therapy....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

In the synthesis of the peptidyl-polymer corresponding to the sequence (57-100) of the ..beta.. chain of human hemoglobin on Teflon with radiationally grafted polystyrene a comparative study was made of different methods of fragment condensation. It was shown that the most effective methods are azide condensation and condensation with the use of complex F.

Energy Technology Data Exchange (ETDEWEB)

A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.

Energy Technology Data Exchange (ETDEWEB)

Electron spin resonance spectroscopy can provide a powerful approach to the study of radiation effects in biological materials. This memorandum gives an overview of current and future research. (author).

International Nuclear Information System (INIS)

The risks to human health from small doses of ionizing radiation raise questions which remain largely unanswered. This paper begins by explaining the historical background to this subject; it goes on to discuss recent developments and concludes with a personal view of the dose-reponse relationship. (author).

UK PubMed Central (United Kingdom)

Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes...Full Text Available

UK PubMed Central (United Kingdom)

PurposeA dosimetric comparison between multiple static-field intensity-modulated radiation therapy (IMRT), multi-arc intensity-modulated arc therapy (IMAT) and single-arc...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This guidebook organizes the profusion of rules and regulations surrounding radiation protection into a single-volume reference. Employee and public protection, accident prevention, and emergency preparedness are included in this comprehensive coverage. Whenever possible, information is presented in convenient checklists, tables, or outlines that enable you to locate information quickly.

International Nuclear Information System (INIS)

Many mechanical parts are subjected to stresses and strains that may eventually lead to their failure. In order to prevent the costly delays associated with equipment down-time, many parts have to be tested for weaknesses and defects when machinery is constructed or dismantled for maintenance. These procedures are known as Non-Destructive Testing (NDT) methods. Five types of non-destructive testing methods routinely used are radiographic testing, ultrasonic testing, magnetic particle inspection, liquid penetrant testing and eddy current testing. Out of these five techniques industrial radiography plays an important role in non-destructive testing to reveal interior defects in materials. In radiography almost two-thirds of the radiation reaching the film is scattered radiation which does not form the image of defects. Scattered radiation generated inside and outside a material has a very large effect on sensitivity of flaw ...