WorldWideScience
1

INITIATION OF EXPLOSIVES BY EXPLODING WIRES. VII. ...  

Science.gov (United States)

... The results should be of interest to personnel engaged in initiation research and design of exploding bridgewire ordnance systems. ...

1965-06-25

3

Reflected-shock initiation of explosives  

Energy Technology Data Exchange (ETDEWEB)

In a study of initiations caused by reflected shock from a high-impedance boundary, attempts to establish sufficient conditions for initiative are described. Shock polar analysis is used to discover the ranges of various flow regimes, general shock structures and pressure estimates of states behind the reflected wave. Using this knowledge, wave structure growth rates from hydrocode simulations are estimated and standard-shock initiation criteria are used; experiments are designed in which the initiation from a reflected-shock wave structure appears likely. Two experiments are described in which a reflected-shock wave from a uranium surface initiated PBX 9502. The experimental evidence is in good agreement with the assumptions and results of the analysis.

1993-08-01

4

The discovery of signal transduction by G proteins. A personal account and an overview of the initial findings and contributions that led to our present understanding  

UK PubMed Central (United Kingdom)

The realization that there existed a G-protein coupled signal transduction mechanism developed gradually and was initially the result of an ill fated quest for uncovering the mechanism of action...Full Text Available

2007-04-01

5

Calculations of physical and chemical reactions produced in irradiated water containing DNA  

Energy Technology Data Exchange (ETDEWEB)

Initial results obtained with a Monte Carlo computer program designed to link initial physical events in irradiated liquid water with subsequent chemical and biological events are presented. 10 refs., 4 figs., 3 tabs.

1985-01-01

6

Application of neutron transmutation doping method to initially p-type silicon material  

Energy Technology Data Exchange (ETDEWEB)

The neutron transmutation doping (NTD) method was applied to the initially p-type silicon in order to extend the NTD applications at HANARO. The relationship between the irradiation neutron fluence and the final resistivity of the initially p-type silicon material was investigated. The proportional constant between the neutron fluence and the resistivity was determined to be 2.3473x10{sup 19} n {omega} cm{sup -1}. The deviation of the final resistivity from the target for almost all the irradiation results of the initially p-type silicon ingots was at a range from -5% to 2%. In addition, the burn-up effect of the boron impurities, the residual {sup 32}P activity and the effect of the compensation characteristics for the initially p-type silicon were studied. Conclusively, the practical methodology to perform the neutron transmutation doping of the initially ...

2009-07-15

7

Application of neutron transmutation doping method to initially p-type silicon material  

International Nuclear Information System (INIS)

The neutron transmutation doping (NTD) method was applied to the initially p-type silicon in order to extend the NTD applications at HANARO. The relationship between the irradiation neutron fluence and the final resistivity of the initially p-type silicon material was investigated. The proportional constant between the neutron fluence and the resistivity was determined to be 2.3473x1019 n ? cm-1. The deviation of the final resistivity from the target for almost all the irradiation results of the initially p-type silicon ingots was at a range from -5% to 2%. In addition, the burn-up effect of the boron impurities, the residual 32P activity and the effect of the compensation characteristics for the initially p-type silicon were studied. Conclusively, the practical methodology to perform the neutron transmutation doping of the initially p-type silicon ingot was ...

2008-05-12

8

Summary of Omega West Reactor, Level 1, probabilistic risk assessment  

International Nuclear Information System (INIS)

This paper reports on a Level 1 PRA performed on the Omega West Reactor at Los Alamos National Laboratory. A Master Logic Diagram was used to identify possible initiating events. A chi-square distribution was used to quantify initiating event frequencies given that no initiating events have occurred in 30 years of OWR operation. The PRA results are presented as both probability density function and cumulative distribution function curves.

1990-10-04

9

Heat treatment effect on impact strength of 40Kh steel  

Energy Technology Data Exchange (ETDEWEB)

The paper presents results of studies on the effect of heat treatment on strength and pattern of 40Kh steel impact failure. Loading levels corresponding to macroscopic spalling microdamage initiation in the material are determined for three initial states. Metallographic study on the spalling failure pattern for 40Kh steel in different initial states and data on microhardness measurement are presented.

1984-01-01

10

Design of optimal control under uncertain initial conditions: A minimax approach  

British Library Electronic Table of Contents (United Kingdom)

The need for a game-theoretical formulation of the problem of linear-quadratic control under nonmeasurable plant state where the functional depends on the uncertain initial state was substantiated. The minimax output control law in terms of linear matrix inequalities that may be regarded as the optimal robust control law for the given set of the plant initial states was established assuming that the measurable components of the initial state were known and the nonmeasurable components take on values within the given ellipsoid. The results obtained were generalized to the plants with uncertain parameters.

2009-01-01

11

Immune aspects of sarcoidosis.  

UK PubMed Central (United Kingdom)

Although the initiating factor(s) is unknown, it is now accepted that pulmonary sarcoidosis develops as a result of an over-stimulated local cellular immune response. Starting as a lymphocytic alveolitis,...Full Text Available

1988-07-01

12

Phase Information and the Evolution of Cosmological Density Perturbations  

CERN Document Server

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel'dovich approximation as an initial motivation, we develop a statistic that quantifies the information content of the distribution of phases. Using numerical simulations beginning with more realistic Gaussian random-phase initial conditions, we show that the information content of the phases grows from zero in the initial conditions, first slowly and then rapidly when structures become non-linear. This growth of phase information can be expressed in terms of an effective entropy: Gaussian initial conditions are a maximum entropy realisation of the initial power spectrum, ...

2000-01-01

13

Application of neutron transmutation doping method to initially p-type silicon material  

British Library Electronic Table of Contents (United Kingdom)

The neutron transmutation doping (NTD) method was applied to the initially p-type silicon in order to extend the NTD applications at HANARO. The relationship between the irradiation neutron fluence and the final resistivity of the initially p-type silicon material was investigated. The proportional constant between the neutron fluence and the resistivity was determined to be 2.3473x1019ncm-1. The deviation of the final resistivity from the target for almost all the irradiation results of the initially p-type silicon ingots was at a range from -5% to 2%. In addition, the burn-up effect of the boron impurities, the residual 32P activity and the effect of the compensation characteristics for the initially p-type silicon were studied. Conclusively, the practical methodology to perform the neut...

2009-01-01

14

Modeling Blast and High-Velocity Impact of Composite Sandwich Panels  

Science.gov (United States)

Analytical models for predicting the deformation and failure of composite sandwich panels subjected to blast and projectile impact loading are presented in this paper. The analytical predictions of the transient deformations and damage initiation in the composite sandwich panels were compared with finite element solutions using ABAQUS Explicit. For the blast model, the predicted transient deformation of the sandwich panel was within 7%of FEA results, while the predicted damage initiation using Hashin's composite failure criteria was about 15%higher than FEA results in most cases. For the high velocity impact model, the predicted transient deformations were within 20%of FEA results.

2009-01-01

15

FMDP Reactor Alternative Summary Report: Volume 2 - CANDU heavy water reactor alternative  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 2 of a four volume report, summarizes the results of these analyses for the CANDU reactor based plutonium disposition alternative.

1996-09-01

16

Experimental research of spontaneous evolution from ultracold rydberg atoms to plasma  

International Nuclear Information System (INIS)

The spontaneous evolution from ultracold Rydberg atoms to plasma is investigated in a caesium MOT by using the method of field ionization. The plasma transferred from atoms in different Rydberg states (n=22-32) are obtained experimentally. Dependence of the threshold time of evolving to plasma and the threshold number of initial Rydberg atoms on the principal quantum number of initial Rydberg states is studied. The experimental results are in agreement with hot-cold Rydberg-Rydberg atom collision ionization theory. (authors)

2008-04-01

17

Evaluation of potential severe accidents during low power and shutdown operations at Surry: Unit 1, Volume 1  

International Nuclear Information System (INIS)

This document contains a summarization of the results and insights from the Level 1 accident sequence analyses of internally initiated events, internally initiated fire and flood events, seismically initiated events, and the Level 2/3 risk analysis of internally initiated events (excluding fire and flood) for Surry, Unit 1. The analysis was confined to mid-loop operation, which can occur during three plant operational states (identified as POSs R6 and R10 during a refueling outage, and POS D6 during drained maintenance). The report summarizes the Level 1 information contained in Volumes 2--5 and the Level 2/3 information contained in Volume 6 of NUREG/CR-6144.

1990-10-22

18

Causes of morbidity among HIV-infected children on antiretroviral therapy in primary care facilities in Lusaka, Zambia  

British Library Electronic Table of Contents (United Kingdom)

Summary Objectives To describe the pattern of incident illness in children after initiation of antiretroviral therapy (ART) in a large public health sector programme in Lusaka, Zambia. Methods Systematic chart review to retrospectively extract data from medical records of children (i.e. <15 years) initiating ART in the Lusaka, Zambia public sector. Incident conditions were listed separately and then grouped according to broad categories. Predictors for incident diagnoses were determined using univariate and multivariable analysis. Results Between May 2004 and June 2006, 1705 HIV-infected children initiated ART. Of these, 1235 (72%) had their medical records reviewed. Median age at ART initiation was 77 months and 554 (45%) were females. Eight hundred and forty-one (68%) children had an inc...

2009-01-01

19

California's Proposition 15: the what and why of its defeat  

International Nuclear Information System (INIS)

This analysis of the June 8, 1976 California Nuclear Initiative was prepared by the Pacific Gas and Electric Co. The defeat of Proposition 15 in the California election was successful for several reasons. A record 70 percent of the voters in California went to the polls and 97 percent of those voted on the nuclear issue with the results showing defeat by two-to-one. Apparently, the voters perceived the Nuclear Initiative as being too drastic. The campaign for defeat of the initiative stressed the consequences of closing down existing plants and closing off the nuclear option in California, namely: higher costs, job losses, and less-desirable alternatives. The campaign waged for the Initiative seems to have suffered from weak management and lack of consistent messages.

20

Dependence of Energy Thresholds on Laser Radiation Wavelength in Initiation of Heavy Metal Azides  

CERN Document Server

The behavior of silver and lead azides (scaly and threadlike crystals, and compacted powders) in initiation of explosive decomposition by laser pulsed radiation has been investigated. Initiation energy thresholds in irradiation at wavelengths of 1064 nm, 532 nm, 354.7 nm, 266 nm corresponding to four laser radiation harmonics have been measured. Samples both uncovered and covered with a transparent dielectric (a quartz plate) with the compressive force of up to 0.5GPa were initiated. In the transparent spectral region (the first and second laser harmonics) of the heavy metal azide matrix the effect of covering the sample surface with a plate on initiation energy threshold was insignificant, whereas, in the region of bandgap absorption (the fourth harmonic) strong dependence of the initiation threshold on whether the surface under irradiation is uncovered or covered. The ...

2010-01-01

21

An analysis of initial thickness and thinning status of feeder pipes in Wolsung unit 1  

Energy Technology Data Exchange (ETDEWEB)

The initial thichnesses of feeder pipes in Wolsung-1 are analyzed to estimate status of feeder thinning. The assumption of the estimation is that feeders of same type are decreased to same thickness by bending and have same thickness after bending. Following three methods are used to estimated thicknesses of the remains besides 52 feeders with initial thickness data in Wolsung-1. First is the estimating initial thickness of same type in Wolsung-1 from initial thickness data of Wolsung-2, -3 and -4. Second is the finding average value of each type from 52 initial thickness data of Wolsung-1. Last is the finding the thickness-after-bending of Wolsung-1 from thickness decrease rate of each type by bending in Wolsung-2, -3 and -4. The first method is eliminated by thickness-before-bending of Wolsung-1 lower than that of Wolsung 2, 3 and 4. The thinning rates of 2nd and 3rd method are ...

2001-05-01

22

An analysis of initial thickness and thinning status of feeder pipes in Wolsung unit 1  

International Nuclear Information System (INIS)

The initial thichnesses of feeder pipes in Wolsung-1 are analyzed to estimate status of feeder thinning. The assumption of the estimation is that feeders of same type are decreased to same thickness by bending and have same thickness after bending. Following three methods are used to estimated thicknesses of the remains besides 52 feeders with initial thickness data in Wolsung-1. First is the estimating initial thickness of same type in Wolsung-1 from initial thickness data of Wolsung-2, -3 and -4. Second is the finding average value of each type from 52 initial thickness data of Wolsung-1. Last is the finding the thickness-after-bending of Wolsung-1 from thickness decrease rate of each type by bending in Wolsung-2, -3 and -4. The first method is eliminated by thickness-before-bending of Wolsung-1 lower than that of Wolsung 2, 3 and 4. The thinning rates of 2nd and 3rd method are ...

2001-05-01

23

Technology  

Indian Academy of Sciences (India)

integration with available technology and initiatives ...

24

Localization of abnormal parathyroid glands using thallium-201  

Science.gov (United States)

Ectopically located parathyroid adenomas may be difficult to find during initial neck exploration. They account for over 70 percent of missed adenomas found at reexploration. Preoperative localization of parathyroid adenomas would reduce unnecessary dissection and possibly reduce the number of negative results of initial neck exploration. Before reoperative parathyroid surgery is performed, some means of localization is mandatory to detect ectopic adenomas in the neck and mediastinum. Computed tomography and ultrasonography cannot effectively evaluate the mediastinum. Angiography and venous parathyroid hormone sampling are invasive, costly, and tedious to perform. We have shown that thallium-201 will accurately localize ectopic parathyroid adenomas. All 10 adenomas found in positions not immediately adjacent to the thyroid gland were detected by thallium-201 scintigraphy. One was a mediastinal adenoma resected with a median ...

1984-07-01

25

Stress Ratio Effects on Small Fatigue Crack Growth in Ti-6Al ...  

Science.gov (United States)

... in Ti-6Al-4V has been studied quite thoroughly [5-7], much of the work resulting from the Air Force-sponsored High Cycle Fatigue initiative [8]. In ...

2008-11-01

26

Seismic Testing of Wolsung-1 Steam Generator Models.  

Science.gov (United States)

This 1978 annual report contains the results of ''Seismic testing of Wolsung-1 steam generator model'' which was initiated in 1977 as a part of a study on nuclear components testing. Model 78, improved version of Model 77 which did not take into account f...

1979-01-01

27

Scheme for Entangling Two Distant Cavity Mirrors  

International Nuclear Information System (INIS)

A scheme is presented for the generation of entangled states for two cavity mirrors. In the scheme each mirror initially in a vacuum state interacts with a weak coherent field, resulting in a photon-number dependent kick. The detection of a photon leaking from the cavities collapses the two mirrors to an entangled state.

2008-04-15

28

Recent Developments in Coal Liquefaction at the Wilsonville Advanced Coal Liquefaction Research and Development Facility.  

Science.gov (United States)

The results of the two most recently completed runs at the Wilsonville Advanced Coal Liquefaction Research and Development Facility are presented. In Run 255, initial screening of operating conditions for the liquefaction of a Texas lignite was completed....

1991-01-01

29

Nuclear structure properties for gamma-ray lasers  

Energy Technology Data Exchange (ETDEWEB)

We summarize some initial results in our investigation of the nuclear physics issues of gamma-ray lasers. We describe what is known thus far from existing experimental data and illustrate how theoretical models may be employed for systematic searches of candidate nuclei.

1986-08-15

30

Nuclear structure properties for gamma-ray lasers  

Energy Technology Data Exchange (ETDEWEB)

We summarize some initial results in our investigation of the nuclear physics issues of gamma-ray lasers. We describe what is known thus far from existing experimental data and illustrate how theoretical models may be employed for systematic searches of candidate nuclei.

1985-01-01

31

Metabolism of the benzidine-based azo dye Direct Black 38 by human intestinal microbiota.  

UK PubMed Central (United Kingdom)

Benzidine-based azo dyes are proven mutagens and have been linked to bladder cancer. Previous studies have indicated that their initial reduction is the result of the azo reductase activity of the intestinal...Full Text Available

1985-07-01

32

Identification of a Central DNA Flap in Feline Immunodeficiency Virus  

UK PubMed Central (United Kingdom)

A duplication of the polypurine tract (PPT) at the center of the human immunodeficiency virus type 1 (HIV-1) genome (the cPPT) has been shown to prime a separate plus-strand initiation and to result...Full Text Available

2001-10-01

33

Doublet III vacuum vessel neutral beam armor  

Science.gov (United States)

The evolution of the Doublet III neutral beam armor is followed from the initial design of a radiation cooled metallic tile to the present actively cooled graphite design. Results of the thermal and stress analyses that dictated the present design are reviewed.

1979-11-01

34

Clinical efficacy of the use of information technology in cardiology: initial results of angiographic teleconsultation in the Netherlands  

UK PubMed Central (United Kingdom)

Background With the increasing use of cineless diagnostic angiography laboratories, modern telecommunication networks provide an excellent opportunity to transfer dynamic cardiac...Full Text Available

2001-12-01

35

An Evaluation of the Value of Choice with Preschool Children  

UK PubMed Central (United Kingdom)

The current study examined the reinforcing effects of choosing among alternatives in a four-part evaluation. In the first study, initial-link responses in a concurrent-chains arrangement resulted in...Full Text Available

2006-01-01

36

Adult Morgagni Hernia: The Need for Clinical Awareness, Early Diagnosis and Prompt Surgical Intervention  

UK PubMed Central (United Kingdom)

We report an unusual case of strangulated diaphragmatic (Morgagni) hernia resulting in ischaemia of the small and large bowel, which was initially diagnosed as a pneumonia. This case highlights the...Full Text Available

2008-11-01

37

Absolute dimensions of unevolved O type close binaries  

Energy Technology Data Exchange (ETDEWEB)

A method is presented to derive the absolute dimensions of early-type detached binaries by combining the observed parameters with results of evolutionary computations. The method is used to obtain the absolute dimensions of nine close binaries. We find that most systems have an initial masss ratio near 1.

1984-03-15

38

Initial RF measurements of the CW normal-conducting RF injector  

Energy Technology Data Exchange (ETDEWEB)

The LANL 2.5-cell, normal-conducting radio-frequency (NCRF) injector has been fabricated. We present initial results of low-power RF measurements (cavity Q, cavity field map, coupling beta, etc.) of the NCRF injector. The measured cavity Q and relative fields are found to be in good agreement with the design calculations and earlier measurements of Glidcop properties. However, the coupling beta of the ridge-loaded waveguides is found to be significantly higher than the design point. The impact of these low-power measurement results on the planned high-power RF and electron beam tests will be discussed.

2008-01-01

39

Estimation of static formation temperatures in geothermal wells  

Energy Technology Data Exchange (ETDEWEB)

Stabilized formation temperatures were estimated at different depths in 40 wells from the Los Humeros geothermal field, Mexico, using the Horner and the spherical radial flow (SRF) methods. The results showed that the Horner method underestimates formation temperatures, while the SRF method gives temperatures that are closer to the true formation temperatures. This was supported by numerical simulation of a combined circulation and shut-in period in several wells, and results for well H-26 are presented. Numerical reproduction of logged temperature is more feasible if an initial temperature profile based on the SRF method is employed instead of using an initial temperature profile based on the Horner method. (Author)

2003-05-01

40

Direct laser initiation of PETN  

Energy Technology Data Exchange (ETDEWEB)

In the early 1970s Yang and Menichelli demonstrated that direct laser illumination of low-density secondary explosive prr:ssings through a transparent window could produce detonation. 'The energy requirement for threshold initiation of detonation was reduced when a thin metal coating of metal covered the side of the window against which the low-density explosive was pressed. We have obtained experimental results that are in general agreement with the results of Renllund, Stanton and Trott (1 989) and recent: work by Nagayama, hou and Nakahara (2001). We report exploration of the effects of laser beam diameter, PEiTN density and specific surface area, and thickness of a titanium coating on the window.

2001-01-01

41

Non-dissipative kinetic simulation and analytical solution of three-mode equations of ion temperature gradient instability  

Energy Technology Data Exchange (ETDEWEB)

A non-dissipative drift kinetic simulation scheme, which rigorously satisfies the time-reversibility, is applied to the three-mode coupling problem of the ion temperature gradient (ITG) instability. It is found from the simulation that the three-mode ITG system repeats growth and decay with a period which shows a logarithmic divergence for infinitesimal initial perturbations. Accordingly, time average of the mode amplitude vanishes, as the initial amplitude approaches to zero. An exact solution is analytically given for a class of initial conditions. An excellent agreement is confirmed between the analytical solution and numerical results. The results obtained here provide a useful reference for basic benchmarking of theories and simulation of the ITG modes. (author)

1999-12-01

42

Effect of initial conditions, boundary conditions and thickness on the moisture buffering capacity of spruce plywood  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the moisture buffering capacity of spruce plywood is measured by recording the change in mass of a test specimen when the air relative humidity (RH) is changed between 33% RH and 75% RH. The aim is to represent diurnal cycles in indoor humidity with 33% RH maintained for 16 h and 75% RH maintained for 8 h. Measurements are taken using two different apparatuses, which provide different convective transfer coefficients between the air and the plywood, and the results are compared to a numerical model for validation. The validated numerical model is then used to investigate the effect of initial conditions, boundary conditions and thickness on the moisture buffering capacity of plywood. The results show that the buffering capacity of plywood depends on the initial conditions and thickness of the plywood as well as the surface film coefficient and humidity cycle. (author)

2006-07-01

43

Ab initio-based approach on initial growth kinetics of GaN on GaN (001)  

British Library Electronic Table of Contents (United Kingdom)

We carried out theoretical analyses based on ab initio calculations that incorporate free energy of the vapor phase in order to determine the initial growth process of cubic GaN on GaN (001)-(4x1). The results suggest that a N-adsorbed structure appears at the initial growth stage and then Ga adsorbs on the N-adsorbed GaN (001)-(4x1) surface. Considering this process, we performed Monte Carlo simulations. The results suggest that the maximum point of Ga coverage after supplying a Formula Not Shown monolayer of atoms shifted toward a Ga-rich condition from V/III=1.0.

2007-01-01

44

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

Energy Technology Data Exchange (ETDEWEB)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K{sup Iscc}, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, ...

2002-07-01

45

Effect of crevice environment PH on corrosion damage of horizontal steam generator tubes  

International Nuclear Information System (INIS)

In support of a project on lifetime calculation experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K"I"s"c"c, and the crack growth rate were made to predict evolution of damage in tube walls. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show that the material of SG tubes is sensitive to transgranular environmentally assisted cracking in the three basic concentrated environments used, ...

2002-05-05

46

Dynamics and developing of natural circulation cooling from vertical upflow and downflow conditions  

International Nuclear Information System (INIS)

Several research programs have been conducted to evaluate the capability of natural circulation cooling of reactors following a loss of cooling accident. Both experimental and RELAP5 simulation results were obtained for these studies in a facility with vertical heated tube(s) and a unheated bypass channel. The analytical results showed that, under a certain power level, a natural circulation pattern can be developed from both initial upflow and downflow conditions, and maintained for a significant cooling period. This power level, for the discussion of this paper, is defined as the natural circulation cooling (NCC) power limit. Two import factors, namely the pump coastdown rate and the initial flow direction, are examined in this paper. In the benchmark case, as compared to the experimental results, the RELAP5 simulation program accurately predicted the transient phenomena from ...

1994-04-05

47

Determination of the initial energy in computerized tomography with proton beams; Determinacao da energia inicial em tomografia computadorizada com feixe de protons  

Energy Technology Data Exchange (ETDEWEB)

In earliest works devoted to proton computed tomography it was shown that the advantage of pCT image reconstruction appears when the energy is close to the Bragg peak region, since the proton passes the object. This effect provided by the Bragg peak makes the computerized tomography with protons possible. However, when decreasing the initial proton energy, with the increase of the irradiation dose, there are two effects that work simultaneously in opposite ways. First, the energy loss of a proton in an object becomes bigger at small initial energy. At the same time decreasing of the proton energy results in the increase of the energy straggling, requiring a larger number of protons. In this work the radiation dose dependence on the proton initial energy was studied using analytical formulas and computer simulations. The investigation determined that the radiation dose practically does not depend on the ...

2007-07-01

48

On synergism in inhibition of liquidphase oxidation of styrene and tetralin by organic phosphites and transition eleement acetylacetonates  

International Nuclear Information System (INIS)

Synergism has been observed during inhibiting initiated oxidation of styrene or tetralin by organic phosphites in the presence of complex compounds of some transition metals. The results are given of non-additive intensification of antioxidative activity of triphenylphosphite (TPP) and tri-(4-methyl-6-tert.-- butyl)-phenyl-phosphite (TMBP) in the process of initiated oxidation of styrene or tetralin with addition of acetylacetonates of cobalt and vanadyl. During styrene oxidation, inhibition of the reaction with chelate complex of vanadyl is weakened considerably when phosphite is added into the reaction system. During tetralin oxidation, postcatalytic (or branched) oxidation is observed only for large concentration of vanadyl complex. Addition of TPP to above complex sharply increases the induction period. When the induction period is completed, oxidation of tetralin follows the mechanism of usual, i.e. ...

49

Experimental characterisation and modelling of crack initiation and short crack propagation for fatigue life prediction of a #beta#-titanium alloy  

International Nuclear Information System (INIS)

Up to 90% of the life time of cyclically loaded components is determined by short crack initiation and propagation. This stage of the fatigue damage process is strongly influenced by microstructural features, e.g. grain boundaries and crystallographic grain orientation. Therefore LEFM can not be applied in a reasonable manner explaining the demand for a mechanism-related modelling method. The present study deals with mechanical testing and microstructural examinations applied to the relatively new #beta#-titanium alloy LCB. The results are used as data base to develop a new short crack model that is based on the model of Navarro and de los Rios. By using various techniques such as electron back-scattered diffraction and finite-element calculations the origin of crack initiation is revealed and the characteristics of crack propagation is determined. (orig.)

2000-02-24

50

Cost-time management for environmental restoration activities at the Department of Energy`s Idaho National Engineering Laboratory, Idaho Chemical Processing Plant  

Energy Technology Data Exchange (ETDEWEB)

Cost-time management methods have been developed by Westinghouse to examine business applications from a cost-time perspective. The initial application of cost-time management within Westinghouse was targeted at reducing cycle time in the manufacturing sector. As a result of the tremendous success of reduced cycle time in manufacturing, Westinghouse initiated application of the management technique to Environmental Restoration activities at its Government Owned Contractor Operated facilities. The Westinghouse initiative was proposed in support of the Department of Energy`s goals for cost effective Environmental Restoration activities. This paper describes the application of the cost-time method to Environmental Restoration work currently being performed at the Idaho National Engineering Laboratory (INEL) for the Department of Energy (DOE) by Westinghouse Idaho Nuclear Company (WINCO).

1992-05-22

51

Cost-time management for environmental restoration activities at the Department of Energy's Idaho National Engineering Laboratory, Idaho Chemical Processing Plant  

International Nuclear Information System (INIS)

Cost-time management methods have been developed by Westinghouse to examine business applications from a cost-time perspective. The initial application of cost-time management within Westinghouse was targeted at reducing cycle time in the manufacturing sector. As a result of the tremendous success of reduced cycle time in manufacturing, Westinghouse initiated application of the management technique to Environmental Restoration activities at its Government Owned Contractor Operated facilities. The Westinghouse initiative was proposed in support of the Department of Energy's goals for cost effective Environmental Restoration activities. This paper describes the application of the cost-time method to Environmental Restoration work currently being performed at the Idaho National Engineering Laboratory (INEL) for the Department of Energy (DOE) by Westinghouse Idaho Nuclear Company (WINCO).

1992-08-23

52

Alkaline treatment of biomass fly ash for reactive dye removal from aqueous solution  

British Library Electronic Table of Contents (United Kingdom)

Biomass fly ash was treated with alkaline solution to enhance its adsorption capacity of Reactive Black 5 dye. The results revealed that the alkaline concentration, solution to fly ash ratio, treatment temperature and treatment time had a positive effect on the dye adsorption capacity of the treated fly ash (TFA), due to dissolving SiO2 and increasing the proportion of unburned carbon. In addition, the dye adsorption behavior of the TFA in aqueous solution was investigated. The effects of various experimental parameters (initial pH, initial dye concentration and contact time) were determined spectrophotometrically. The dye adsorption capacity of the TFA was maximized at an alkaline pH (8.2-10.4). The adsorption capacity of dye by the TFA increased with increasing initial dye concentration....

2010-01-01

53

Stress corrosion cracking of Alloy 600 using the constant strain rate test  

International Nuclear Information System (INIS)

Nuclear grade production tubing of Alloy 600 was evaluated for stress corrosion cracking (SCC) susceptibility in high purity water at 365, 345, 325, and 290 C. Reverse tube U-bend specimens provided crack initiation data and constant extension rate tests were employed to determine the crack velocities experienced in th crack propagation stage. Initial results indicate that a linear extrapolation of data received from high temperature tests can be used to predict the service life of steam generator tubing that has been plastically deformed or is continually deforming by ''denting.''.

54

Preliminary reactor cavity melt dispersal model for direct containment heating scenarios  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of a series of experiments performed to study the effect of initial pressure vessel conditions on the extent of melt dispersal from scaled reactor cavities and describes progress in development of a mathematical model which is designed to predict the melt mass dispersed from reactor cavities as a function of reactor vessel initial conditions and on the vessel breach area. The model, which is being developed to also characterize the heat transfer and chemical reaction phenomena which would take place within the reactor cavity, is designed to be incorporated into a lumped-parameter containment analysis computer code.

1989-01-01

55

Hanford tanks initiative plan  

Energy Technology Data Exchange (ETDEWEB)

Abstract: The Hanford Tanks Initiative (HTI) is a five-year project resulting from the technical and financial partnership of the U.S. Department of Energy`s Office of Waste Management (EM-30) and Office of Science and Technology Development (EM-50). The HTI project accelerates activities to gain key technical, cost performance, and regulatory information on two high-level waste tanks. The HTI will provide a basis for design and regulatory decisions affecting the remainder of the Tank Waste Remediation System`s tank waste retrieval Program.

1997-07-01

56

Analytical laboratory and mobile sampling platform. Progress report, October 1, 1994--December 31, 1994  

Energy Technology Data Exchange (ETDEWEB)

This paper is a quarterly report describing the use of a new soil gas collection device which allows the collection of soil gas in the field for later analysis in the laboratory. It describes the installation of this sampling device and the procedure for setting the probe, extraction of soil gas beneath the surface, and sealing of the soil gas for transport. The sites used for initial testing was the top of Yucca Mountain and Crystal Spring in Ash Meadows National Wildlife Refuge. The results from this initial test showed no volatile matter present in the soil at these locations.

1994-12-31

57

Comparison of results of two dye-tracer tests at the Chestnut Ridge Security Pits, Y-12 Plant, Oak Ridge, Tennessee  

Energy Technology Data Exchange (ETDEWEB)

Personnel from Martin Marietta Energy Systems, Inc. (Energy Systems) manage a closed hazardous waste disposal unit the Chestnut Ridge Security Pits (CRSP), located on the crest of Chestnut Ridge near the Y-12 Plant, Oak Ridge, Tennessee. To investigate the discharge of groundwater from CRSP to springs and streams located along the flanks and base of Chestnut Ridge, an initial dye-tracer study was conducted during 1990. A hydraulic connection was inferred to exist between the injection well (GW-178) on Chestnut Ridge and several sites to the east-northeast, east, and southeast of CRSP. A second dye-tracer study was conducted in 1992 to verify the results of the initial test and identify additional discharge points that are active during wet-weather conditions. No definitive evidence for the presence of dye was identified at any of the 35 locations monitored during the second dye study. Although interpretations of the ...

1994-01-01

58

Status of the surry low power and shutdown PRA  

International Nuclear Information System (INIS)

The Surry low power and shutdown probabilistic risk analysis (PRA) is an ongoing project at Brookhaven National Laboratory (BNL) to identify and quantify potential accident scenarios that may occur in a pressurized water reactor (PWR) during low power and shutdown. It was initiated as a result of various incidents and accidents that have occurred within the United States and overseas. The project involves review and evaluation of PWR experience at shutdown, identification of accident scenarios, determination of methods to mitigate the accidents, and performance a level 1 PRA. An evaluation of accident progression, source terms and consequences has also been initiated. The results will be used to address issues related to shutdown conditions. The objective of this paper is to provide a progress report on the project, and to present the approach used as well as the preliminary results ...

1991-04-01

59

Development of a high-output dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of a new dual-fuel engine development program. The engine is the largest commercially available in terms of power output (650 hp/cyl) and features very low emissions (1 g/hp-hr NO[sub x]) and excellent fuel consumption (43 percent thermal efficiency). A two-cylinder turbocharged prototype was designed and built for the initial development. Results from testing on 18-cylinder production versions are also reported.

1993-10-01

60

Detecting mining subsidence from space  

Energy Technology Data Exchange (ETDEWEB)

The aim is to provide accurate data on elevation change due to mining activity, via the application of interferometry with ERS SAR data. Ultimately, these elevation changes can then be fed into subsidence models. Interferometry results are presented showing initial evidence of subsidence occurring within the 35 day repeat orbit period of the ERS satellites. The result of extending the monitoring period beyond 35 days is also shown.

1999-04-01

61

Energy efficient soil disinfestation by microwaves  

Energy Technology Data Exchange (ETDEWEB)

A major obstacle prohibiting the use of microwaves for soil disinfection and disinfestation is the large amount of energy required to obtain sufficient results. The present work presents an experimental study of the effect of initial soil temperature and soil moisture on energy consumption by application of microwaves for soil disinfection. All experiments were carried out by using a microwave generator of a nominal power output of 900 W. The ultra-high-frequency field (2450{+-}2 MHZ) was produced by a magnetron tube and channelled through a metal waveguide. The output opening of the waveguide was placed directly on the soil surface. It was found that a soil with 15% moisture content (w.b.) and an initial temperature of 20degC requires energy to be heated at a depth of 10 cm up to 61degC which is 3.2 times more than the energy required to heat the soil up to 5 cm depth at the same initial temperature. ...

2000-02-01

63

Theoretical approach to initial growth kinetics of GaN on GaN(001)  

British Library Electronic Table of Contents (United Kingdom)

We carried out theoretical analyses based on ab initio calculations incorporates in which free energy of the vapor phase is incorporated in order to determine the initial growth kinetics of c-GaN on GaN(001)-(4x1). The feasibility of the theoretical approach had been confirmed by calculations of Ga adsorption-desorption transition temperature and transition beam equivalent pressures on the GaAs(001)-(4x2)b2 surface in our previous work [Y. Kangawa, T. Ito, A. Taguchi, K. Shiraishi, T. Ohachi, Surf. Sci. 493 (2001) 178]. The results of calculations suggest that no Ga adsorption occurs on the initial surface under typical growth conditions but that a Ga adsorption site appears after N adsorption on GaN(001)-(4x1). That is, in the initial growth stage of c-GaN on GaN(001)-(4x1), a N-adsorbed ...

2007-01-01

64

Stress corrosion cracking in high-purity water of 3-31/2% NiCrMoV low-alloy steels for steam turbine disks and rotors. Pt. 1  

International Nuclear Information System (INIS)

In recent years intergranular stress corrosion cracking has occurred world-wide in the shrink-fitted discs of low pressure turbine rotors made of low alloy steels. Only in a few cases steam impurities such as NaOH, Na_2CO_3, Na_2SO_4, H_2S or NaCl, which initiate SCC, could be found. To clarify the SCC-behaviour experiments on turbine disc steels with different chemical compositions and yield strength were performed in high purity water. The results show, that chemical composition has no effect on the crack initiation. Under high purity water conditions no crack initiation due to stress corrosion cracking is observed on the steel with a yield strength of 850 N/mm"2. On the steel with a yield strength of 1250 N/mm"2 which is not used in service, crack initiation occurs in pure water. But if sharp cracks already exist, crack propagation occurs in both cases. The investigations showed, ...

65

Possible preparation of wood-plastic materials based on unsaturated polyester resins and methyl metacrylate, by radiation and chemical methods in combination  

Energy Technology Data Exchange (ETDEWEB)

The preparation of wood-plastic combinations (WPC) using combined methods for curing intermediate products and final products is described. In the first step, impregnated wood was irradiated using doses of 1 to 10 kGy in the presence of chemical initiators of polymerization. Thereafter, curing of this partly cured impregnating mixture was accomplished in the wood at elevated temperatures with the aid of chemical initiators of polymerization. Impregnation mixtures based on unsaturated polyester resins and methyl methacrylate, and the wood species European Beech (Fagus silvatica) and Black Alder (Alnus glutinosa) were used. The results indicate that this method of preparing WPC allows substantially lower radiation doses to be used, i.e., doses in the range of 1 to 2.5 kGy. These doses gelatinate the impregnation mixture in the wood so that the subsequent curing by chemical polymerization initiators ...

1982-04-01

66

Possible preparation of wood-plastic materials based on unsaturated polyester resins and methyl metacrylate, by radiation and chemical methods in combination  

International Nuclear Information System (INIS)

The preparation of wood-plastic combinations (WPC) using combined methods for curing intermediate products and final products is described. In the first step, impregnated wood was irradiated using doses of 1 to 10 kGy in the presence of chemical initiators of polymerization. Thereafter, curing of this partly cured impregnating mixture was accomplished in the wood at elevated temperatures with the aid of chemical initiators of polymerization. Impregnation mixtures based on unsaturated polyester resins and methyl methacrylate, and the wood species European Beech (Fagus silvatica) and Black Alder (Alnus glutinosa) were used. The results indicate that this method of preparing WPC allows substantially lower radiation doses to be used, i.e., doses in the range of 1 to 2.5 kGy. These doses gelatinate the impregnation mixture in the wood so that the subsequent curing by chemical polymerization initiators ...

1982-01-01

67

Equilibrium and thermodynamic parameters of single and binary mixture biosorption of lead (II) and copper (II) ions onto Pseudomonas putida: Effect of temperature  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm{sup -3}. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics ...

2006-07-31

68

Dissociative electron attachment to rovibrationally excited molecules. Annual technical report no. 1, 1 August 1984-30 September 1985  

Energy Technology Data Exchange (ETDEWEB)

The aim of this project is to investigate the dependence of the cross sections for dissociative electron attachment to a molecule on the initial rovibrational state of the molecule. An enhancement of the cross section results in the enhancement of the rate of production of negative ion beams. Preliminary investigations reveal that for lithium dimers, Li/sub 2/, the peak attachment cross sections can increase by almost an order of magnitude if the molecule is initially vibrationally excited to the v = 1 level. Excitation to higher vibrational levels would result in further enhancement of the attachment rates. As part of present investigations, the cross sections for vibrational excitation of various molecules, using both resonant and nonresonant mechanisms is calculated.

1985-09-30

69

Computer simulation of the initial rafting process of a nickel-base single-crystal superalloy  

Energy Technology Data Exchange (ETDEWEB)

Rafting of the {gamma}/{gamma}{prime} morphology of nickel-base superalloys is a well-known phenomenon during high-temperature deformation. The initial stages of this type of directional coarsening were modeled two-dimensionally by the method of finite elements (FEs) using an energy-perturbation approach. In addition to the elastic energy density, the effect of the local difference of the hydrostatic stresses in {gamma} and {gamma}{prime} in combination with the different lattice parameters of the two phases was considered in the calculations as a further driving force. From the results of modeling, the deformation-induced internal stresses and strains were determined and used to evaluate the direction-dependent lattice parameters and lattice misfits of the two phases. The results agree well with experimentally determined values.

2000-03-01

70

Application of a New Approach for Estimating LOCA and SGTR Frequencies  

Energy Technology Data Exchange (ETDEWEB)

The needs for more reasonable estimations for rare and extremely rare initiating events (IEs) have been reported in US peer review results. The American Society of Mechanical Engineers (ASME) PRA standard also proposes guidelines and requirements about the issues. Recently, US NRC addressed problems and the conservative assumptions on loss-of-coolant accident (LOCA) analysis and attempted to establish more rigorous methodology for estimating the frequencies depending on break size. The results of peer reviews for KHNP reference plants also represented that the data used in estimating IEs were outdated and the methodology also needed to be improved. In this paper, for more appropriate estimation of rare and extremely rare initiating events (IEs), e.g., LOCAs and steam generator tube ruptures (SGTRs), a new approach considering expert elicitation process is presented and corresponding core damage ...

2010-05-15

71

Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1. Volume 2, Part 1C: Analysis of core damage frequency from internal events for plant operational State 5 during a refueling outage, Main report (Sections 11--14)  

Energy Technology Data Exchange (ETDEWEB)

This document contains the accident sequence analysis of internally initiated events for Grand Gulf, Unit 1 as it operates in the Low Power and Shutdown Plant Operational State 5 during a refueling outage. The report documents the methodology used during the analysis, describes the results from the application of the methodology, and compares the results with the results from two full power analyses performed on Grand Gulf.

1994-06-01

72

Numerical modeling of slug flow initiation in a horizontal channels using a two-fluid model  

International Nuclear Information System (INIS)

This paper presents a methodology for modeling slug initiation and growth in horizontal ducts. Transient two-fluid equations are solved numerically using a class of high-resolution shock capturing methods. The advantage of this method is that slug formation and growth in a stratified regime can be calculated directly from the solutions to the flow field differential equations. In addition, by using high-resolution shock capturing methods that do not contain numerical diffusion, the discontinuity generated by slugging in the flow field can be modeled with good accuracy. The two-fluid model is shown to be well-posed mathematically only under certain conditions. Under these circumstances, the two-fluid model is capable of correctly predicting and modeling the flow physics. When ill-posed, an unbounded instability occurs in the flow field solution, and the instability amplitude increases exponentially with decreasing mesh sizes. This work shows that there are three ...

2011-02-01

73

Repeat Stereotactic Radiosurgery for Acoustic Neuromas  

International Nuclear Information System (INIS)

Purpose: To evaluate the outcome of repeat stereotactic radiosurgery (SRS) for acoustic neuromas, we assessed tumor control, clinical outcomes, and the risk of adverse radiation effects in patients whose tumors progressed after initial management. Methods and Materials: During a 21-year experience at our center, 1,352 patients underwent SRS as management for their acoustic neuromas. We retrospectively identified 6 patients who underwent SRS twice for the same tumor. The median patient age was 47 years (range, 35-71 years). All patients had imaging evidence of tumor progression despite initial SRS. One patient also had incomplete surgical resection after initial SRS. All patients were deaf at the time of the second SRS. The median radiosurgery target volume at the time of the initial SRS was 0.5 cc and was 2.1 cc at the time of the second SRS. The median margin dose at the time of the ...

2010-02-01

74

Thermal fatigue failure at the White Cliffs solar thermal power plant  

Energy Technology Data Exchange (ETDEWEB)

The failure of receivers has been one of the main operating problems at the White Cliffs solar thermal power plant. This Technical Note reports the results of an initial investigation that identifies the cause as having been their thermal fatiguing of the tube walls. The fatigue appears to be caused by unstable heat transfer at vapor qualities below the point where critical heat flux is generally exceeded. Methods for avoiding this problem are tested.

1995-02-01

75

The unique hypusine modification of eIF5A promotes islet ? cell inflammation and dysfunction in mice  

UK PubMed Central (United Kingdom)

In both type 1 and type 2 diabetes, pancreatic islet dysfunction results in part from cytokine-mediated inflammation. The ubiquitous eukaryotic translation initiation factor 5A (eIF5A), which is the...Full Text Available

2010-06-01

76

Some features of chemoradiopathomorphosis of Ewing's sarcoma and reticulum cell sarcoma  

International Nuclear Information System (INIS)

The paper is concerned with the results of a morphological study following chemoradiotherapy in 25 patients with Ewing's sarcoma and 14 patients with reticulum cell carcoma. The signs of therapeutic pathomophosis were observed in the first 3 days, and substitution of the connective tissue for a necrotized tumor started by the 3rd-4th week after the initiation of therapy. In some cases tumor growth and recurrences at the site of a treated tumor were observed.

77

Self-simulating motion of an ionized gas expelled by a magnetic piston  

Energy Technology Data Exchange (ETDEWEB)

The paper deals with a model in which the motion of a gas in plasma accerators and high-curent discharges in the present of a skin effect is treated as expulsion by a 'magnetic piston' under the action of surface current flow. Specifically examined is the situation where the initial gas pressure is negligible in comparison with the magnetic pressure, and the motion of the gas may be treated as a self-simulating one. A system of hydrodynamic equations of the problem is derived and integrated by Adam's method. Results are plotted and discussed.

1980-01-01

78

Radiation hardening of a high voltage IC technology (BCDMOS)  

International Nuclear Information System (INIS)

A program was undertaken to radiation harden an existing power integrated circuit technology (BCDMOS) to total dose, gamma dot, SEU, and neutrons. Efforts have centered around hardening and optimizing our CMOS, DMOS, and NPN devices. Initial results indicate a substantial improvement in hardness over our existing commercial technology.

1990-07-16

79

Performance of CDF calorimeter simulation for Tevatron Run II  

Energy Technology Data Exchange (ETDEWEB)

The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.

2002-09-19

80

On the Effects of Idiotypic Interactions for Recommendation Communities in Artificial Immune Systems  

CERN Document Server

It has previously been shown that a recommender based on immune system idiotypic principles can out perform one based on correlation alone. This paper reports the results of work in progress, where we undertake some investigations into the nature of this beneficial effect. The initial findings are that the immune system recommender tends to produce different neighbourhoods, and that the superior performance of this recommender is due partly to the different neighbourhoods, and partly to the way that the idiotypic effect is used to weight each neighbours recommendations.

2008-01-01

81

Non-uniqueness in conformal formulations of the Einstein constraints  

CERN Document Server

Standard methods in non-linear analysis are used to show that there exists a parabolic branching of solutions of the Lichnerowicz-York equation with an unscaled source. We also apply these methods to the extended conformal thin sandwich formulation and show that if the linearised system develops a kernel solution for sufficiently large initial data then we obtain parabolic solution curves for the conformal factor, lapse and shift identical to those found numerically by Pfeiffer and York. The implications of these results for constrained evolutions are discussed.

2006-01-01

82

Nature Of Tube Degradation In Horizontal Steam Generators  

Energy Technology Data Exchange (ETDEWEB)

Nature of tube degradation was studied in support of horizontal steam generator lifetime calculations. Experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K(ISCC), and the crack growth rate were made to predict evolution of damage in tube walls. Experimental results were compared with in-service inspections experience. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show ...

2002-07-01

83

Nature Of Tube Degradation In Horizontal Steam Generators  

International Nuclear Information System (INIS)

Nature of tube degradation was studied in support of horizontal steam generator lifetime calculations. Experiments were carried out to evaluate the resistance to environmentally assisted cracking (EAC) of steam generator tubes during operation. Estimations of the incubation period for crack initiation and the threshold K value, K(ISCC), and the crack growth rate were made to predict evolution of damage in tube walls. Experimental results were compared with in-service inspections experience. The paper summarizes results of experiments of C ring specimen for the initiation testing and results of SENT (single edge notch tensile) specimen for the crack growth rate (CGR) testing. The specimens were exposed to concentrated environments at elevated temperatures simulating crevice environments in secondary side crevices in horizontal steam generators. The results show ...

2002-09-23

84

Modelling of the wall jet in a direct injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

As a part of a phenomenological model, a method for simulating the wall/jet interaction in a direct injection diesel engine is proposed. The method is based on the application of the momentum conservation equation in the different directions in which the wall jet is spread, and takes into account both the interaction with the combustion chamber geometry and with swirl. It takes as initial conditions the results of calculating the free jet, which is divided into packages. The predictions provide good agreement with those by other researchers. (author).

1992-01-01

85

Modeling of defect-phosphorus pair diffusion in phosphorus-implanted silicon  

International Nuclear Information System (INIS)

The point-defect-impurity pair diffusion model proposed recently by Mulvaney and Richardson is adopted and modified to simulate the coupled diffusion of phosphorus and self-interstitials in phosphorus-implanted silicon. The assumption of implantation-induced, but empirically determined initial interstitial distributions of Gaussian shape allows a simulation of the net effect of transient enhanced diffusion. As a result an improved modeling of phosphorus diffusion in silicon is achieved for a broad range of ion-implantation and annealing conditions. (author).

86

Leveraging limited research and development (R&D) resources in the public sector  

Energy Technology Data Exchange (ETDEWEB)

Mission-directed public-sector research facilities are experiencing increasingly severe budget environments while seeing expanding missions and responsibilities. In an effort to identify research leveraging methodologies an information search was conducted in conjunction with some efforts to find the proper links to systems engineering fundamentals. The result is an initial model for use in a pre-concept/phase-1 engineering design organization, with a goal of improving the organizations performance.

1996-12-01

87

Late effects of "2"3"9Pu administered at representative stages of gestation  

International Nuclear Information System (INIS)

The protocol for a systematic comprehensive study of the influence of prenatal exposure on the tumorigenic and other adverse effects of "2"3"9Pu is described. The study has been initiated, all animals have been weaned, and postnatal function is being evaluated, although results are not yet available.

1977-05-01

88

Initial and mid-term results of a 4F compatible self-expanding low strut profile nitinol stent in the superficial femoral artery  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To evaluate the initial and mid-term results of a new self-expanding low strut profile nitinol stent for treatment of atherosclerotic lesions stenoses and occlusions in the superficial femoral artery (SFA). Materials and Methods: In 8 patients (4 male, 4 female, mean age 74.8 {+-} 8.8 years) with SFA lesions and non-satisfying results after PTA treatment alone, 10 self-expanding nitinol Xpert stents were deployed via a 4 F sheath. Stent characteristics and handling were graded by the interventionalist. Fontaine classification, duplex flow measurements and ankle brachial index (ABI) at rest and stress were taken prior and one day after stent placement. Patients were followed 3, 6 and 12 months after the procedure obtaining the same parameters at each appointment. Results: Initial stent treatment was successful in all patients. Stent handling and positioning were rated very ...

2007-07-15

89

Hazardous materials in Aquatic environments of the Mississippi River basin. Quarterly project status report, 1 January 1994--30 March 1994  

Energy Technology Data Exchange (ETDEWEB)

Projects associated with this grant for studying hazardous materials in aquatic environments of the Mississippi River Basin are reviewed and goals, progress and research results are discussed. New, one-year initiation projects are described briefly.

1994-06-01

90

GaInP/GaAs tandem concentrator cells  

Energy Technology Data Exchange (ETDEWEB)

We discuss the initial development of a concentrator device based on the GaInP/GaAs monolithic tandem cell structure. The very high one-sun efficiency of this device, coupled with its characteristic low operating current, make this a promising candidate for use under high concentration. Test results for a prototype device are presented. This device achieves an efficiency of 29.5% at a concentration of 102 suns.

1994-06-30

91

Enrichment of americium-242m and americium-242 isotopes by means of Szilard-Chalmers method using americium-241 diphthalocyanine complex  

International Nuclear Information System (INIS)

Results of americium-242m and americium-242 preparation by irradiating initial americium-241 at a reactor in the form of a diphtalocyanine complex are presented. The enrichment coefficient, equalling 10, has been obtained using the extraction method of recoil atom separation from the parent isotope. Application of the chromatographic column with Dowex-50 permits to increase the enrichment coefficient of isotopes upto 24.6.

92

Effect of lifetime nutrition on ruminant carcass and meat quality  

Environmental Research Database

DescriptionThis application is a request for Bridge Link funds to support studies in order to develop a full proposal under the Link Sustainable Livestock Scheme in collaboration with Dr Nigel Scollan of IGER. The hypothesis being examined is that the poor performance of some ruminants is due to poor nutrition at strategic time points during the animal's development. The initial hypothesis will be tested in sheep and the results from this will be used to develop the full proposal. Excessive fat in ruminan [continued...

2006-01-31

93

Dynamical evolution and molecular abundances of interstellar clouds  

International Nuclear Information System (INIS)

Dynamical models are presented that start with interstellar gas in an initial diffuse state and consider their gravitational collapse and the formation of dense cores. Frozen-in tangled magnetic fields are included to mimic forces that might oppose gravitational contraction and whose effectiveness may increase with increasing core densities. Results suggest the possibility that dense cloud cores may be dynamically evolving ephemeral objects, such that their lifespan at a given core density decreases as that density increases. 66 refs.

94

Development of an experimental installation for short-lived isotopes production in INR linac  

International Nuclear Information System (INIS)

A possibility of short-lived isotopes production in inter-tank section between the first and the second drift tube tanks (20.45 MeV) in INR linac is considered. At the initial stage the main efforts are concentrated on production of fluorine-18 used for positron emission tomography. The results of beam forming calculations, target heating calculations, equipment activation calculations as well as installation configuration and design are presented.

2010-01-01

95

DISPOSAL OF FLUE GAS DESULFURIZATION WASTES: EPA SHAWNEE FIELD EVALUATION  

Science.gov (United States)

The report summarizes results of the flue gas desulfurization (FGD) waste disposal field evaluation project sponsored by EPA at TVA's Shawnee steam plant, Paducah, KY. This pilot-scale project, initiated in 1974 and completed in September 1980, evaluated methods and costs for dis...

96

Catalysis over activated zeolites  

Science.gov (United States)

A process is provided for conducting organic compound conversion over a catalyst composition comprising a supported crystalline zeolite having a high initial silica-to-alumina mole ratio, said supported zeolite being prepared by compositing said crystalline zeolite with alumina, reacting the composite with a particular hydrogen fluoride solution in a specified way, drying the hydrogen fluoride reacted composite, treating the dried composite by hydrolysis, ammonolysis and/or by contact with an ammonium salt solution, and calcining the resulting material.

1985-02-19

97

Are there tachyons in extensive air showers?  

International Nuclear Information System (INIS)

The results obtained by studying double-front extensive air showers in which more than 107 particles are contained and in which the fronts are separated by a time interval of #DELTA#t #approx# 100 ns are presented. Serious difficulties in explaining 'delayed' showers are revealed. In this connection, a hypothesis that the 'leading' showers are initiated by tachyons produced in the first interaction of primary particles is proposed.

2010-05-01

98

A multi-megawatt X-band solid state microwave switch  

Energy Technology Data Exchange (ETDEWEB)

The authors present design methodology and initial experimental results for a high power microwave switch. The switch is designed for application to the pulse compression system associated with the Next Linear Collider Test Accelerator (NLCTA). The switch is based on the excitation of a plasma layer within a silicon wafer by either a laser or an electron beam. They investigate problems associated with high power operation of such a switch. They explore solutions to the problems of thermal runaway, avalanche breakdown, photo-emission, and secondary emission.

1995-12-31

99

Measurement and analysis of temperature, strain and stress of foundation mat concrete in nuclear and thermal power stations  

International Nuclear Information System (INIS)

The problems of the thermal stress in concrete structures are roughly divided into the initial stress due to setting heat and the stress due to external temperature after hardening. The initial stress exists in every concrete structure, and it is usually neglected in beams and columns, but it must be taken into account in case of the foundation mat structures in nuclear power stations, for example. In this paper, (1) the results of measurement of temperature, strain and stress in each lift at the time of and after placing concrete in the foundation mat of a nuclear power station and the comparison of them with the results of analysis, (2) the results of measurement of the temperature and stress in a foundation mat, which was carried out to rationalize the design method for the raft type foundation mats in thermal power stations, and (3) the results of ...

100

Thulium laser resection via a flexible cystoscope for recurrent non-muscle-invasive bladder cancer: initial clinical experience  

British Library Electronic Table of Contents (United Kingdom)

OBJECTIVE To present our initial experience of thulium laser resection via a flexible cystoscope for recurrent non-muscle-invasive bladder cancer (ThuRBT), as transurethral resection for bladder tumour (TURBT) is regarded as the reference standard for treating this disease, but alternative laser resection or ablation is suitable especially for recurrent tumours. PATIENTS AND METHODS From January 2005 to October 2005, 32 patients with early recurrent bladder tumour (recurrent within a year after TURBT) were treated with ThuRBT via a flexible cystoscope. The follow-up included urine analysis, ultrasonography and cystoscopy every 3 months. RESULTS All patients were treated successfully with ThuRBT in one session, with no bladder haemorrhage, obturator nerve reflex or vesicle perforation. Rand...

2008-01-01

101

Texture development and texture influence on the mechanical properties of the Mg-alloy AZ31  

Energy Technology Data Exchange (ETDEWEB)

The texture influence on tensile tests of AZ31, one of the common Mg alloys, has been studied. Starting material was a rectangular extruded bar, which has a strong texture. Due to the preparation of three tensile samples with 0 , 45 , 90 to the extrusion direction, the initial bar texture influences differently on the mechanical behaviour under tensile load. This results in a variation of the yield strength (90 MPa and 175 MPa) the ultimate tensile strength (250 MPa - 278 MPa) and the final texture. Experimental texture analysis was completed by texture simulations using the VPSC-model (visco plastic self-consistent). The good agreement between experimental and simulated pole figures allows the determination of the activated deformation modes related to the initial texture. (orig.)

2002-07-01

102

Surfactant studies for bench-scale operation. Quarterly technical progress report No. 1, 1 July-30 September 1992  

Energy Technology Data Exchange (ETDEWEB)

A phase 2 study was initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: the refurbishment of the high-pressure, high-temperature reactor autoclave, the completion of four coal liquefaction runs with Pittsburgh No. 8 coal, two each with and without sodium lignosulfonate surfactant, and the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.

1992-12-01

103

Study of technetium chemistry. Pt.10: Qsar analysis of "9"9Tc"m-labelled N_2S_2 analogues of brain imaging agents  

International Nuclear Information System (INIS)

Quantitative structure activity relationship (QSAR) analysis of the correlations between initial brain uptake and structure parameters, for example lipophilicity F_r, molar refractivity MR and electronic parameters #sigma#_1 of the "9"9Tc"m-N_2S_2 complexes have been studied with multiple regression analysis method. The main structural factors which affect the initial brain uptake of this kind of brain imaging agents have been discussed. The results may give some theoretical information for designing new brain imaging agents

1998-02-01

104

Greenhouse gas management - discussion paper  

International Nuclear Information System (INIS)

Canada has undertaken to stabilize greenhouse gas emissions to 1990 levels by the year 2000. To achieve that objective, a voluntary challenge registry (VCR) plan was initiated by the federal and provincial governments to encourage industry, governments, and public sector to take voluntary actions that would contribute to the reduction of greenhouse gas emissions. The initiatives that CAPP member companies have taken were outlined in CAPP's 1995 Action Plan: Climate Change Voluntary Challenge, which was included with this report. The measures reported to date resulted in CO_2 reductions of 812,722 tonnes per year. The report provided a chronological review of CAPP actions in the field of climate changes since 1989, a summary of member action plans, and a listing of new technologies and their impact on greenhouse gas emissions.

105

Desorption of b-carotene from mesoporous carbon coated monolith: Isotherm, kinetics and regeneration studies  

British Library Electronic Table of Contents (United Kingdom)

b-carotene, a natural antioxidant, beneficial form human health prospective. In this study we had examined the recovery of b-carotene form mesoporous carbon coated monolith (MCCM) by batch process. Desorption kinetics and isotherm studies were carried out by using n-hexane as an eluent. Isotherm studies showed better applicability of Langmuir model. The first-order two-compartment three-parameter kinetics model as a function of initial loading concentration and reaction temperature was applied. It was observed that b-carotene desorption process is controlled by both rapid and slow desorption. Results showed that the slow desorption fraction increases from 0.8446 to 0.9007 with increase in initial loading concentration from 10.83 to 39.72mg/g while, the slow desorption fraction decreases fr...

2011-01-01

106

Computational study of non-stationary cluster size distribution and rate of nucleation in case of pre-existing clusters  

International Nuclear Information System (INIS)

The dynamics of a cluster-type system formed by constant total number of molecules, M, is studied when clusters change their sizes by nearest-size transitions (the Szilard model) with time-dependent boundary conditions and non-zero initial cluster size distribution. We compare these results to those reported previously, when non-stationary cluster size distribution was considered under the condition that only monomers are present in the system at the initial moment t=0, and describe the effect of arbitrary pre-existing clusters on the time evolution of the interacting clusters with different sizes, n. The average group size problem is also solved, and the process of relaxation in the system is studied. authors)

107

Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

2010-06-15

108

Assessment of the efficiency of short term countermeasures following a severe accident on a PWR  

Energy Technology Data Exchange (ETDEWEB)

In case of a severe nuclear accident at a PWR plant, countermeasures will be initiated in the short term by authorities to reduce the consequences of the atmospheric radioactive releases on the neighbouring population. Various factors influence the level of protection afforded by countermeasures. For instance, a too late intervention would lead to a Jack of efficiency in terms of dose reduction if the actual evolution of the accident is not considered. Thus, implementation of countermeasures should be optimized. In general, the projected doses (those without countermeasure) are compared with those expected when a particular countermeasure or strategy is implemented. In this paper, an in-depth analysis associates the kinetics of the release with the corresponding evolution of the dosimetric efficiency of countermeasures. This is done at different times in the short term of the accident and for various distances from the plant. Results are ...

2001-07-01

109

Aerobic Decolorization and Detoxification of a Disperse Dye in Textile Effluent by a New Isolate of Bacillus sp.  

British Library Electronic Table of Contents (United Kingdom)

A number of aerobic species capable of decolorizing some of the dyes in a textile mill effluent were isolated. One of the isolates was able to decolorize Terasil black dye under aerobic conditions in the presence of an exogenous carbon source after 5 days. Glucose or starch (%1 ea) are essential for decolorization but the process proceeds faster in the presence of 0.5% yeast extract. Results of the BOD5 show that the untreated effluent samples have a low BOD value, whereas treated samples show an initial increase in BOD up to 15 days followed by a decrease after 20 days. FT-IR and GC-MS data also reveal that the initial components in the untreated effluent disappear after 20 days of treatment, confirming biodegradation of the dye. Phytotoxicity tests on the untreated effluent samples using...

2006-01-01

110

A novel approach to the dynamics of Szekeres dust models  

CERN Document Server

We obtain an elegant and useful description of the dynamics of Szekeres dust models (in their full generality) by means of "quasi--local" scalar variables constructed by suitable integral distributions that can be interpreted as weighed proper volume averages of the local covariant scalars. In terms of these variables, the field equations and basic physical and geometric quantities are formally identical to their corresponding expressions in the spherically symmetric LTB dust models. Since we can map every Szekeres model to a unique LTB model, rigorous results valid for the latter models can be readily generalized to a non--spherical Szekeres geometry. The new variables lead naturally to an initial value formulation in which all scalars are expressed as scaling laws in terms of their values at an arbitrary initial space slice. These variables also yield a significant simplification of numerical work, since the fluid flow ...

2011-01-01

111

Systems analysis of the CANDU 3 Reactor  

International Nuclear Information System (INIS)

This report presents the results of a systems failure analysis study of the CANDU 3 reactor design; the study was performed for the US Nuclear Regulatory Commission. As part of the study a review of the CANDU 3 design documentation was performed, a plant assessment methodology was developed, representative plant initiating events were identified for detailed analysis, and a plant assessment was performed. The results of the plant assessment included classification of the CANDU 3 event sequences that were analyzed, determination of CANDU 3 systems that are ''significant to safety,'' and identification of key operator actions for the analyzed events.

112

Simulation of Pulsed Neutron Activation using a CFD code  

International Nuclear Information System (INIS)

Tests for the applicability of a CFD (Computational Fluid Dynamics) code for simulating activity transport in PNA (Pulsed Neutron Activation) fluid measurements have been performed. The CFD code was combined with a Monte Carlo code used for the calculation of the initial activity distribution. The results from the calculations show that it is possible to use CFD for calculation of the activity distribution in PNA. The mainly qualitative results in this work are encouraging and suggest further work. In the continuation of this work a response function for the gamma detector will be calculated so that a PNA time spectrum can be simulated. A more accurate comparison with experimental data can then be performed

2008-09-14

113

Proposition of the Interactive Pareto Iterated Local Search Procedure - Elements and Initial Experiments  

CERN Document Server

The article presents an approach to interactively solve multi-objective optimization problems. While the identification of efficient solutions is supported by computational intelligence techniques on the basis of local search, the search is directed by partial preference information obtained from the decision maker. An application of the approach to biobjective portfolio optimization, modeled as the well-known knapsack problem, is reported, and experimental results are reported for benchmark instances taken from the literature. In brief, we obtain encouraging results that show the applicability of the approach to the described problem.

2008-01-01

114

Low temperature proton irradiation of amorphous Pd/sub 80/Si/sub 20/ prepared by ion implantation  

Energy Technology Data Exchange (ETDEWEB)

The damage induced by low-temperature proton irradiation in amorphous Pd/sub 80/Si/sub 20/ prepared by ion implantation is studied via electrical resistivity measurements. Our experimental results concerning the initial damage rate and the resistivity saturation are compared to the results obtained for electron and high energy /sup 16/O irradiation of amorphous Pd/sub 80/Si/sub 20/ quenched from the melt. The resistivity curve is analyzed in terms of irradiation-induced point defects.

1984-05-01

115

Initial results from 50mm short SSC dipoles at Fermilab  

Energy Technology Data Exchange (ETDEWEB)

Several short model SSC 50 mm bore dipoles are being built and tested at Fermilab. Mechanical design of these magnets has been determined from experience involved in the construction and testing of 40 mm dipoles. Construction experience includes coil winding, curing and measuring, coil end part design and fabrication, ground insulation, instrumentation, collaring and yoke assembly. Fabrication techniques are explained and construction problems are discussed. Similarities and differences from the 40 mm dipole tooling and management components are outlined. Test results from the first models are presented. 19 refs., 12 figs.

1991-03-01

116

Improved economies in the use of natural gas  

Energy Technology Data Exchange (ETDEWEB)

Preheating processed materials and combustion air can result in processing and fuel-efficiency gains in industrial smelting furnaces. For example, fuel consumption in reverberatory furnaces used in copper smelting would drop by as much as 63% at the same throughput by preheating the charge in a countercurrent mode to 1400/sup 0/F by exhaust gases that have an initial temperature of 2500/sup 0/F. Concurrent charge preheating would result in a maximum decrease of 46% in natural gas consumption. An analysis of these gains also provides equations for calculating investment returns and nomographs for optimizing charge-preheating temperatures for reverberatory furnaces.

1981-12-01

117

How to start a utility TQM program  

Energy Technology Data Exchange (ETDEWEB)

Huntsville, Alabama Utilities has successfully provided services for over 53 years. However, the quality of service demands from customers are changing every day! Part of this demand is due to updated digital appliances, home and business computers, and automated systems. A quality program was initiated in 1992 as a result of an internal assessment. The Malcolm Baldrige approach was selected which includes seven areas: (1) Leadership; (2) Information and Analysis; (3) Strategic Planning; (4) Human Resource Utilization; (5) Quality Assurance of Products and Services: (6) Quality Results: (7) Customer Satisfaction. Training for and implementation of the Quality program is discussed in detail.

1994-12-31

118

Conditional risk assessment of SNR 300 in case of an unprotected loss of flow accident  

International Nuclear Information System (INIS)

This paper gives a summary of a risk study assuming unprotected loss of flow (ULOF) in the SNR 300. This study was initiated in 1979/80 by the Karlsruhe Nuclear Research Center and performed in close cooperation with Science Applications Inc., Palo Alto, USA, and Interatom Company. Part of the results also was integrated in the 'Risk Related Analysis for the SNR 300' carried out by the Gesellschaft fuer Reactorsicherheit. The character of the study described here is similar to other risk studies like the Reactor Safety Study and the German Risk Study for Nuclear Power Plants. The objectives and the methodology of the analyses are described and its results are discussed. (orig./RW).

119

Calculation of eddy current losses in metal parts of power transformers  

Energy Technology Data Exchange (ETDEWEB)

To maintain quality, performance and competitiveness, the eddy current losses in metal parts of power transformers in the range of 50-200 MVA are investigated in a more detailed form. The finite element calculations utilize different modelling strategies for the current carrying metal parts. Several global and local results are further used to obtain simplified calculation approaches for an inclusion in the initial design and the design optimization. The results from two finite element approaches using nodal and edge based formulations will be compared with measurements. (Author)

2003-04-01

120

Simulation of natural convection cooling phenomena for research reactors using the code PARET  

International Nuclear Information System (INIS)

This study deals with testing the capability of the code PARET to simulate natural convection cooling phenomena under different boundary conditions. In addition to applying and testing some new options related to simulation of the control rod movement and studying the reactivity effect of thermal expansion fuel elements. The experiments of the simple thermal hydraulic loop of Missouri university about natural cooling phenomena in two narrow paralled channels were used to validate the code. The study indicate good results regarding the distribution of coolant flux velocity and clad temperature. In particular the heat transfer coefficient of natural convection has been calculated in good agreement with the experiment. On the other hand, the core of MNSR reactor has been modelled to simulate the reactor dynamic behaviour under natural convection cooling conditions for different initial power level. The observed oscillation during the ...

121

Simulation of natural convection cooling phenomena for research reactors using the code PARET  

International Nuclear Information System (INIS)

This study deals with testing the capacity of the code PARET to simulate natural circulation phenomena under different boundary conditions in addition to assessment of some new options related to simulation of control rod movement and the reactivity effect of thermal expansion fuel elements. the experiments of the simple thermal hydraulic loop of Missouri University about natural circulation phenomena in narrow parallel channel were used to validate the code. The results indicate good agreements regarding the evolution of coolant velocity and clad temperature. In particular the heat transfer coefficient of natural convection has been calculated in good agreement with the experiment. On the other hand, the core of MNSR reactor has been modelled to stimulate the reactor dynamic behaviour under natural circulation condition for different initial power level. The observed oscillations during the initial phase vanish gradually ...

122

Differential expression of fatty acid uptake in 3T3-L1 cells  

Energy Technology Data Exchange (ETDEWEB)

Cultured 3T3-L1 cells have been used as a model system to investigate the mechanism of fatty acid uptake by adipose tissue. Using a 1:1 molar ratio of /sup 14/C-oleate and defatted bovine serum albumin (BSA), fatty acid (FA) uptake was quantitated at 4/sup 0/ and 37/sup 0/ as cell associated radioactivity. The profile of FA uptake in preadipocytes and adipocytes was biphasic; an initial rapid phase (1-20s) followed by a second slower phase (60-480s). At 37/sup 0/ the initial rate of FA accumulation in preadipocytes was identical to that in adipocytes, whereas the rate of accumulation during the second phase increased 7-fold (100 ..mu..M total FA) as a consequence of adipose conversion. When uptake measurements were made at 4/sup 0/ in adipocytes, the initial rate was identical to that at 37/sup 0/, however the rate of second phase decreased 5-fold. Incubation of /sup 14/C-BSA and nonradiolabeled FA with adipocyte monolayers ...

1987-05-01

123

Resistance and resilience of tundra plant communities to disturbance by winter seismic vehicles  

International Nuclear Information System (INIS)

Effects of winter seismic exploration on arctic tundra were evaluated on the coastal plain of the Arctic National Wildlife Refuge, four to five growing seasons after disturbance. Plant cover, active layer depths, and track depression were measured at plots representing major tundra plant communities and different levels of initial disturbance. Results are compared with the initial effects reported earlier. Little resilience was seen in any vegetation type, with no clearly decreasing trends in community dissimilarity. Active layer depths remained greater on plots in all nonriparian vegetation types, and most plots still had visible trails. Decreases in plant cover persisted on most plots, although a few species showed recovery or increases in cover above predisturbance level. Moist sedge-shrub tundra and dryas terraces had the largest community dissimilarities initially, showing the least resistance to ...

124

Reactions of 3-methylpentane and 2,3-dimethylbutane on aluminosilicate catalysts  

Science.gov (United States)

Catalytic reactions of 3-methylpentane and 2,3-dimethylbutane on HY, amorphous silica-alumina, and HZSM-5 have been studied at 500{degree}C. Both kinetic phenomena and product selectivities have been reported. Cracking reactions an HZSM-5 can be attributed to initiation through protonation occurring at Bronsted sites. Bimolecular processes leading to chain reaction via hydride transfer are restricted within the narrow pore pentasil zeolite. On HY and amorphous silica-alumina, initiation of cracking also occurs at Bronsted sited. No direct evidence was found for participation of Lewis acid sites on the catalyst framework itself. Following initiation, reactions on these catalysts are accelerated through a chain process occurring at Lewis sites generated by adsorption of product olefins at Bronsted sites. The resulting change in the dominant cracking mechanism is reflected in the product selectivity, ...

1990-12-01

125

Localized deformation and IASCC initiation in austenitic stainless steels  

International Nuclear Information System (INIS)

Localized deformation may play a key role in the underlying mechanism of irradiation assisted stress corrosion cracking (IASCC) in light water reactor core components. In this study, four austenitic alloys, 18Cr8Ni, 15Cr12Ni, 13Cr15Ni and 21Cr32Ni, with different stacking fault energies were irradiated to 1 and 5 dpa at 360 deg. C using 3.2 MeV protons. Interrupted constant extension rate tensile (CERT) tests were conducted in a simulated BWR environment to determine IASCC susceptibility. In order to characterize the localized deformation in slip channels and grain boundaries, parallel CERT experiments were also performed in an argon atmosphere. Results show that the IASCC susceptibility of the tested alloys increases with increasing irradiation dose and decreasing stacking fault energy. IASCC tends to initiate at locations where slip channels intersect grain boundaries. Localized deformation in the form of grain boundary sliding due to the ...

2008-12-01

126

Hyperfractionated radiotherapy with simultaneous chemotherapy in Ewing's sarcoma  

International Nuclear Information System (INIS)

In 1981, the German Society of Pediatric Oncology initiated a multi-institutional study for the treatment of Ewing's sarcoma. The protocol (Cooperative Ewing's Sarcoma Study, CESS 81) consisted of four courses of a four-drug-regimen (VACA), each course taking nine weeks. Local therapy (radical surgery or resection plus irradiation or radiotherapy alone) was performed after the second course. The results of CESS 81 can be summarized as follows: VACA-chemotherapy is effective in controlling systemic disease. Initial tumor mass and response to initial chemotherapy are of major prognostic value for local control and survival. Permanent local control is a problem, especially in irradiated patients. The high local failure rate in irradiated patients in CESS 81 could be attributable to the following reasons: Late start of local therapy (after 18 weeks of chemotherapy), uneven distribution of prognostic ...

127

A corporate social responsibility initiative in the field of nuclear power  

International Nuclear Information System (INIS)

Societatea Nationala Nuclearelectrica SA is the operator of the Cernavoda nuclear power plant and the second largest energy producer in Romania, after Hidroelectrica, ensuring 18% of the internal energy demand. The production of nuclear power differs from other industrial activities through the risks it involves and through the legacy it leaves to the future generations, i.e. the nuclear waste. Taking into account these considerations, public acceptance represents a constant preoccupation for nuclear companies around the world. Corporate Social Responsibility (CSR) is a new practice in the nuclear industry. After a long tradition of involvement in the life of the local community through the Social Program for Cernavoda, Nuclearelectrica has initiated a CSR campaign with the theme 'Welcome a tree in your family', addressed to pupils and high school students from Cernavoda. By this campaign, we aimed at creating relevance, not just green lots and to launch a chain of ...

2009-10-12

128

Comparative thermal cyclic test of different beryllium grades previously subjected to simulated disruption loads  

Energy Technology Data Exchange (ETDEWEB)

Considering beryllium as plasma facing armour this paper presents recent results obtained in Russia. A special process of joining beryllium to a Cu-alloy material structure is described and recent results of thermal cycling tests of such joints are presented. Summarizing the results, the authors show that a Cu-alloy heat sink structure armoured with beryllium can survive high heat fluxes ({>=}10 MW/m{sup 2}) during 1000 heating/cooling cycles without serious damage to the armour material and its joint. The principal feasibility of thermal cycling of beryllium grades and their joints directly in the core of a nuclear reactor is demonstrated and the main results of this test are presented. The paper also describes the thermal cycling of different beryllium grades having cracks initiated by previously applied high heat loads simulating plasma disruptions. (orig.)

1999-11-01

129

UNITED STATES DEPARTMENT OF ENERGY WASTE PROCESSING ANNUAL TECHNOLOGY DEVELOPMENT REPORT 2007  

Energy Technology Data Exchange (ETDEWEB)

The Office of Environmental Management's (EM) Roadmap, U.S. Department of Energy--Office of Environmental Management Engineering & Technology Roadmap (Roadmap), defines the Department's intent to reduce the technical risk and uncertainty in its cleanup programs. The unique nature of many of the remaining facilities will require a strong and responsive engineering and technology program to improve worker and public safety, and reduce costs and environmental impacts while completing the cleanup program. The technical risks and uncertainties associated with cleanup program were identified through: (1) project risk assessments, (2) programmatic external technical reviews and technology readiness assessments, and (3) direct site input. In order to address these needs, the technical risks and uncertainties were compiled and divided into the program areas of: Waste Processing, Groundwater and Soil Remediation, and Deactivation and Decommissioning (D&D). Strategic ...

2008-08-12

130

Optimization of sorghum-methane production systems  

Energy Technology Data Exchange (ETDEWEB)

This dissertation concerns a study of the utilization of sorghum biomass as the fuel for a methane production system. The objective of this research is to determine an optimal sorghum-methane production system based on anaerobic batch digestion technology. The system is described as the interaction of three components: estimation of available biomass, storage of biomass, and the gas production. Levelized costs are obtained for each component. The biomass supply is assumed to decay exponentially in quality with storage time. The gas production process is a batch type of digestion with an exponential production rate. Gas production is formulated for a fixed planning horizon (one year) as a function of the number of batches and the batch residence times. The cost equation is then described as a function of these gas production equations and their levelized costs. The structure of this resulting equation is exploited to obtain the minimum unit gas cost. This analysis ...

1984-01-01

131

Development of advanced residential cooktop burner with low NO/sub x/ emissions. Annual report Feb 82-Jan 83  

Science.gov (United States)

This report describes the results of work conducted during February 1982 - January 1983. A literature search was initiated to identify the state-of-the-art of NOx (NO + NO/sub 2/) reduction technologies, including NOx measurement methodologies, air infiltration and ventilation trends, the impact of NOx (NO/sub 2/) emissions on health, and air quality standards. As a result of the literature search NOx (NO/sub 2/) reduction goals were established for the project and technologies to achieve these goals identified. This report also covers the development of a prototype burner which examined flue gas recirculation, burner designs, secondary air baffling and flame inserts as potential technologies to reduce NOx (NO/sub 2/). Because of their potential for NOx (NO/sub 2/) reduction shown by initial experiments, an in-depth analysis of ring insert configurations was conducted. These ...

1983-02-28

132

Characterization and remediation of highly radioactive contaminated soil at Hanford  

Energy Technology Data Exchange (ETDEWEB)

The Hanford Site, Richland, Washington, contains over 1,500 identified waste sites and numerous groundwater plumes that will be characterized and remediated over the next 30 years. As a result of the Hanford Federal Facility Agreement and Consent Order, the US Department of Energy (DOE) has initiated a remedial investigation/feasibility study (RI/FS) at the 200-BP-1 operable unit. The 200-BP-1 RI/FS is the first Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) investigation on the Hanford Site that involves highly radioactive and chemically contaminated soils. The initial phase of site characterization was designed to assess the nature and extent of contamination associated with the source waste sites within the 200-BP-1 operable unit. Characterization activities consisted of drilling and sampling, chemical and physical analysis of samples, and development of a conceptual vadose zone model. ...

1993-09-01

133

Pit Lake modelling phase 2 task A : validation and refinement of existing RMA10 and DYRESM Pit Lake hydrodynamic results[End Pit Lake phase 2 modelling  

Energy Technology Data Exchange (ETDEWEB)

This interim technical report presented a summary of results obtained from Pit Lake models developed from different simulation models. The models were used to predict stratification in a hypothetical Pit Lake. Predictions were used to assess the hydrodynamic similarities and differences between the 2 models and to determine if the models would produce similar stratification profiles for the Pit Lakes to previous models. Results showed that the models produced similar results for both temperatures and salinities. The main difference between the RMA10 and CE-QUAL-W2 model used in a previous study was found to be run time. A sensitivity analysis of the RMA10 and CE-QUAL-W2 model predictions was completed to assess the effects of segmentation; time step; lake surface area; lake orientation; and model coefficients or parameters. Results showed that the selected time step and model segmentation were ...

2006-06-15

134

[Fast neutron cross section measurements]. Progress report  

Energy Technology Data Exchange (ETDEWEB)

In this report, we outline the progress achieved in two distinct under the DOE-sponsored cross section project: the initial results obtained from the pulsed 14 MeV neutron facility, and a cooperative effort with Argonne National Laboratory in the measurement of fast neutron cross sections in yttrium. In the 14 MeV neutron laboratory, this year has seen the maturation of the project into one in which initial scattering measurements are now underway. We have improved the accelerator and ion source in several significant ways, so that neutron intensities have now been proven to be adequate for our series of elastic scattering angular distribution measurements outlined in our initial proposal of two years ago. We have successfully tested all components of the time-of-flight spectrometer and recorded initial neutron spectra from the ring targets that we have obtained for our first ...

1991-12-31

135

Regional yields simulation for winter wheat in North China based on assimilating remote sensing data  

Science.gov (United States)

Accurate crop growth monitoring and yield forecasting are significant to food security and sustainable development of agriculture. However, regional crop growth simulation faces the difficulties in determining the spatial distribution of some model parameters and initial conditions. In this study, regional biomasses at turn-green stage of winter wheat were re-estimated by linking WOFOST model and Soil Adjusted Vegetation Index (SAVI) synthesized from remote sensing data. Moreover, we proposed a way of combining evapotranspiration derived from satellite remote sensing data to crop grow simulation model. Thus, the regional initial available soil water and irrigation at earring stage were re-initialized and re-estimated by using remote sensing data. Those methods were well applied to simulate the growth and development for winter wheat at local site. After regionalizing of weather data, crop model parameters and ...

2006-09-01

136

Environmental mitigation for SCC initiation of BWR core internals by hydrogen injection during start-up  

Energy Technology Data Exchange (ETDEWEB)

Hydrogen injection into the reactor water has been applied to many BWR power stations. Since hydrogen injected accelerates recombination of oxidant generated by water radiolysis, oxidant concentration, such as dissolved oxygen concentration in reactor water can be reduced. As the result of the reduction of oxidant concentration, Electrochemical Corrosion Potential (ECP) at the surface of structural material can be lowered. Lowered ECP moderates Stress Corrosion Cracking (SCC) sensitivity of structural materials, such as stainless steels. As usual, hydrogen injection system begins to work after the plant start-up is finished, when the condition of normal operation is established. Accordingly, Hydrogen Water Chemistry (HWC) does not cover all the period of plant operation. As far as SCC crack growth is considered, loss of HWC during plant start-up does not result in significant crack growth, because of duration of plant start-up is much shorter ...

2004-07-01

138

A new self-expanding nitinol stent (Enterprise) for the treatment of wide-necked intracranial aneurysms: initial clinical and angiographic results in 31 aneurysms  

Energy Technology Data Exchange (ETDEWEB)

We report the results of a prospective clinical study using a new self-expanding nitinol stent (Enterprise) designed for the treatment of wide-necked intracranial aneurysms. We treated 31 saccular, wide-necked intracranial aneurysms in 30 patients. Ten aneurysms had recanalized after prior endovascular treatment without a stent, and 21 aneurysms had not been treated before. Stent deployment was successful in all procedures. Additional coil embolization was performed in all aneurysms. Initial complete angiographic occlusion was achieved in 6 aneurysms, a neck remnant was left in 18 aneurysms and there were 7 residual aneurysms. Angiographic follow-up examinations of 30 lesions after 6 months demonstrated 15 complete occlusions, 8 neck remnants and 7 residual aneurysms. One patient refused the 6-month angiographic follow-up. Spontaneous occlusion of the aneurysm had occurred in 14 patients, and 6 aneurysms showed recanalization. Four of these ...

2007-07-15

139

PROCEEDINGS OF ELECTRIC INITIATOR SYMPOSIUM. ...  

Science.gov (United States)

... 5. EXPLODING BRIDGEWIRE INITIATION OF RDX WITH 50 MILLIJOUUS RM Hillyer, Naval Ordnance Laboratory, Corona, Calif. .... ...

1963-10-01

140

EXPLODING BRIDGEWIRE INITIATION OF CAST ...  

Science.gov (United States)

... Accession Number : AD0368940. Title : EXPLODING BRIDGEWIRE INITIATION OF CAST EXPLOSIVES. Descriptive Note : Final rept. ...

1965-12-01

141

Thermal cracking of black oil fuel in a mixture with shale  

British Library Electronic Table of Contents (United Kingdom)

The results of studies performed for the development of a new process of the thermal cracking of tar as a suspension with ground Baltic oil shale in order to obtain motor fuel components are reported. The experimental results suggest undoubted advantages of the process over industrial thermal cracking because the deep degradation of tar (the yields of a gasoline fraction with bp to 180?C, middle distillates with bp of 180?360?C, and feedstock for catalytic cracking with bp of 360?520?C were ~12, 43?44, and ~15?16 wt % on an initial tar basis) was achieved upon the single-stage processing of the raw material under relatively mild conditions (5 MPa, 425?C, and a feed space velocity of 1.0 h?1). The resulting coke-like products and V and Ni contained in the raw material were deposited on the ...

2011-01-01

142

Observation of the study of protein metabolism in relation to nutrition  

International Nuclear Information System (INIS)

It is a useful hypothesis to thing of the reaction to protein deprivation as made up of two parts. First there is an initial adaptation involving rapid losses of protein. This is followed by slow continuing depletion. When considering two organ groups, such as the liver and muscle, it appears that the curve of urinary nitrogen excretion reflects the different parts they play in these two phases. The changes in the relative amounts of protein in different organs results in an alteration in the pattern of body protein at the level of the organ, the tissue and the cell. These changes are themselves the result of altered rates of synthesis and breakdown. The questions that must be asked and hopefully will be answered with the help of isotopes, are how these changes are brought about, how they are inter-related and controlled, and what is their significance? This paper contains a discussion of the few ...

1965-06-01

143

Auger electron spectroscopy studies of GaAs and Si metal-semiconductor structures  

Science.gov (United States)

The use of Auger electron spectroscopy (AES) combined with in situ sputter etching for revealing the metallurgy of the metal-semiconductor interface is presented. The physical basis, measurement techniques, and data interpretation for Auger analysis of thin-film structures are briefly reviewed. Results of a detailed study of an alloyed multilayered contact (Ni/Au-Ge) on n-type epitaxial GaAs are summarized to illustrate how electrical and metallurgical contact properties can be correlated using AES. In addition, the results of a study of the growth kinetics and chemical phase identification of palladium silicide on single-crystal Si is given, as well as the initial results of a study of aluminum-palladium silicide interaction at elevated temperature. (auth)

1975-01-01

144

Auger electron spectroscopy studies of GaAs and Si metal-semiconductor structures  

International Nuclear Information System (INIS)

The use of Auger electron spectroscopy (AES) combined with in situ sputter etching for revealing the metallurgy of the metal-semiconductor interface is presented. The physical basis, measurement techniques, and data interpretation for Auger analysis of thin-film structures are briefly reviewed. Results of a detailed study of an alloyed multilayered contact (Ni/Au-Ge) on n-type epitaxial GaAs are summarized to illustrate how electrical and metallurgical contact properties can be correlated using AES. In addition, the results of a study of the growth kinetics and chemical phase identification of palladium silicide on single-crystal Si is given, as well as the initial results of a study of aluminum-palladium silicide interaction at elevated temperature.

145

The Mass Spectra, Hierarchy and Cosmology of B-L MSSM Heterotic Compactifications  

CERN Document Server

The matter spectrum of the MSSM, including three right-handed neutrino supermultiplets and one pair of Higgs-Higgs conjugate superfields, can be obtained by compactifying the E_{8} x E_{8} heterotic string and M-theory on Calabi-Yau manifolds with specific SU(4) vector bundles. These theories have the standard model gauge group augmented by an additional gauged U(1)_{B-L}. Their minimal content requires that the B-L gauge symmetry be spontaneously broken by a vacuum expectation value of at least one right-handed sneutrino. In previous papers, we presented the results of a quasi-analytic renormalization group analysis showing that B-L gauge symmetry is indeed radiatively broken with an appropriate B-L/electroweak hierarchy. In this paper, we extend these results by 1) enlarging the initial parameter space and 2) explicitly calculating all renormalization group equations numerically, without approximation. The regions of the ...

2010-01-01

146

Supporting Thermal Hydraulic Calculations for the SGTR Event Tree of SMART Level 1 PSA  

International Nuclear Information System (INIS)

SMART (System integrated Modular Advanced ReacTor) , is under development at the Korea Atomic Energy Research Institute (KAERI). SMART is an integral type pressurized water reactor which contains a pressurizer, 4 reactor coolant pumps (RCPs), and 8 steam generator cassettes(S/Gs) in a single reactor vessel. This reactor has substantially enhanced its safety with an integral layout of its major components, 4 trains of safety injection system (SIS), and an adoption of 4 trains of passive residual heat removal system (PRHRS) instead of an active auxiliary feedwater system . The thermal power is 330 MWth. During the conceptual design stage, a preliminary PSA was performed. PSA results identified that a steam generator tube rupture (SGTR) is one of the most important initiating events which results in a high core damage frequency. Clear understanding of accident progression with various combinations of the safety systems helps ...

2010-10-01

147

Repair of the radiation induced rectovaginal fistulas without or with interposition of the bulbocavernosus muscle (Martius procedure)  

Energy Technology Data Exchange (ETDEWEB)

Two local repair procedures, one without (9) and the other with (14) a bulbocavernosus muscle graft were performed on 20 patients with a radiation induced rectovaginal fistula. Four patients had two procedures successively. The initial success rate of both procedures was 7/9 and 14/14 respectively. Though the initial result of the bulbocavernosus graft was obviously better, in many of the local repair procedures, subclinical radiation damage progressed, resulting in recurrence of rectovaginal fistula (5), rectovesical fistula (4), pararectal abscess (2) etc. After a mean follow up of around 10 years, the success rate of fistula repair decreased to 5/9 and 13/14 and only 2/9 and 6/14 finally remained without a colostomy. A local repair operation should be restricted to carefully selected cases. The musculus gracilis is proposed as a better vascular graft. If the general condition of the patient does not ...

1988-04-01

148

PET/MRI hybrid imaging: devices and initial results  

International Nuclear Information System (INIS)

The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest PET/MRI developments use solid-state light detectors that can be operated even at high magnetic fields. Initial pilot studies with prototype animal PET/MRI systems have shown ...

2008-06-01

149

Design/build/mockup of the Waste Isolation Pilot Plant gas generation experiment glovebox  

Energy Technology Data Exchange (ETDEWEB)

A glovebox was designed, fabricated, and mocked-up for the WIPP Gas Generation Experiments (GGE) being conducted at ANL-W. GGE will determine the gas generation rates from materials in contact handled transuranic waste at likely long term repository temperature and pressure conditions. Since the customer`s schedule did not permit time for performing R&D of the support systems, designing the glovebox, and fabricating the glovebox in a serial fashion, a parallel approach was undertaken. As R&D of the sampling system and other support systems was initiated, a specification was written concurrently for contracting a manufacturer to design and build the glovebox and support equipment. The contractor understood that the R&D being performed at ANL-W would add additional functional requirements to the glovebox design. Initially, the contractor had sufficient information to design the glovebox shell. Once the shell design was approved, ANL-W ...

1996-10-01

150

DELAYED FAILURE AND HYDROGEN EMBRITTLEMENT IN TITANIUM. Period covered February 3, 1957 to February 3, 1958  

Science.gov (United States)

S>Hydrogen-induced delayed failure in an alpha-beta titanium alloy (4Al-- 4Mn) was sensitive to microstructure. A quenched structure was less susceptible to delayed failure than aged or annealed structures. The tendency for delayed failure was magnified in all structures by an increase in hydrogen content or an increase in strength level. Hydrogen-induced delayed failure occurred by a process of crack initiation and controlled crack growth. Delayed failures resulting from creep were also encountered. Plastic strain resulting from creep tended to retard crack initiation. Changes occurring in material under static load prior to formation of cracks were reversible, as long as no appreciable plastic strain occurred, indicating stress-induced diffusion of hydrogen. Hydrogen-induced delayed failure disappeared at both high and low temperatares. The time required for failure as ...

1958-02-01

151

Biased power spectrum and bispectrum for an ensemble of three-dimensional scale free numerical simulations  

CERN Document Server

We examine the effect of a threshold bias on the power spectrum and the bispectrum in an ensemble of numerical simulations (Gaussian initial perturbations with power law spectra P(k) \\sim k^n, n=+1, 0, -1, -2) and compare our results with theoretical predictions. Our simulations are evolved sufficiently that on the scale where we apply the threshold the rms fluctuation has developed significantly into the nonlinear regime. Thus, predictions based on perturbation theory do not necessarily apply. Nevertheless, we find our results for the power spectrum, biased power simply amplified by a numerical factor, follow predicted trends, far beyond the regime where perturbation theory is expected to be valid. We find that the biased bispectrum continues to follow the so-called hierarchical form, with reduced three-point amplitude Q \\approx 1 in the strongly nonlinear regime, independent of initial spectrum. In ...

1994-01-01

152

Adiabatic interpretation of particle creation in a de Sitter universe  

Energy Technology Data Exchange (ETDEWEB)

The choice of vacuum state for a quantum scalar field propagating in a de Sitter spacetime (massive and arbitrarily coupled to the gravitational field) is discussed. The problem of finite-time initial conditions for the mode functions is analyzed, as well as how these determine the vacuum state of the quantum system. The principle guiding the choice of vacuum state is the following: one wants the vacuum contribution to the energy-momentum tensor to contain all the ultraviolet divergent terms, so that the particle creation terms are finite, and covariantly conserved. There is a suitable set of modes (instantaneous adiabatic basis) in which this splitting of the expectation value of the energy-momentum tensor can be carried out. Numerical results are presented for different finite-time initial conditions (m = 0.6, {zeta} = 1/6). The nature of the particle creation effect is described and its relationship to the concept of a ...

1998-06-10

153

A pulse-width modulated, high reliability charge controller for small photovoltaic systems  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of a development effort to design, test and begin production of a new class of small photovoltaic (PV) charge controllers. Sandia National Laboratories provided technical support, test data and financial support through a Balance-of-System Development contract. One of the objectives of the development was to increase user confidence in small PV systems by improving the reliability and operating life of the system controllers. Another equally important objective was to improve the economics of small PV systems by extending the battery lifetimes. Using new technology and advanced manufacturing techniques, these objectives were accomplished. Because small stand-alone PV systems account for over one third of all PV modules shipped, the positive impact of improving the reliability and economics of PV systems in this market segment will be felt throughout the industry. The results of verification testing of the new ...

1997-02-01

154

Wood-plastic composites with high toughness and dimensional stability  

International Nuclear Information System (INIS)

Using acrylic-group containing isocyanates together with methyl methacrylate as impregnating mixture and gamma rays for curing wood-plastic composites have been produced, which show high-dimensional stability and toughness (low brittleness) compared to commonly used wood-plastics. The syntheses of proper acrylic-group containing isocyanates are as well described as the properties of the produced composites, made from maple wood. Also the direct use of the initial compounds, necessary for the syntheses, resulted in products of similar properties. These wood-plastic composites are to be suggested for the production of high-class products, e.g. wood-wind instruments. (author).

1982-10-01

155

Wastewater treatment of industrial effluent using activated dolomite adsorption  

Environmental Research Database

SummaryInitial results from the use of activated dolomite from QUESTOR project L1 have proved extremely encouraging in terms of metallic ion (also phosphate, nitrate and dye) removal from wastewater, with capacities in some instances in excess of commercially available activated carbons.This new project involves investigating actual plant effluent in laboratory scale columns and the design of a pilot scale rig for on site trials. The project also involves investigating disposal options and an economic [continued...

2007-01-01

156

Vortex generator induced heat transfer augmentation past a rib in a heated duct air flow  

Energy Technology Data Exchange (ETDEWEB)

The present investigation represents the initial phase of a comprehensive experimental program designed to study the potential for increasing the heat transfer per unit pressure drop in a ribbed duct by positioning vortex generators at key locations in the flow. In particular, the present investigation consists of a rib positioned at the inlet to a rectangular test section with uniform heating at its bottom wall. Local and average Nusselt number results are obtained for a circular rod positioned either immediately above or just downstream of the rib.

1992-02-01

157

Thermal Cycling of Thin and Thick Ply Composites  

Energy Technology Data Exchange (ETDEWEB)

An experimental study was conducted to determine the effects of ply thickness in composite laminates on thermally induced cracking and changes in the coefficient of thermal expansion (CTE). After a few thermal cycles, laminates with thick-plies cracked, resulting in large changes in CTE. CTE`s of the thin-ply laminates were unaffected by microcracking during the first 500 thermal cycles, whereas, the CTE`s of the thick-ply laminates changed significantly. After about 1500 cycles, microdamage had also reduced the CTE of the thin-ply laminates to a value of about half of their initial value.

1994-01-01

158

The Stefan problem of evaporation of a volatile component from a binary liquid mixture  

Science.gov (United States)

The study is concerned with the Stefan problem of evaporation of a volatile component from its solution with a virtually non-volatile material. The analysis provides an analytical solution to the problem based on mass-transfer fundamentals. Results yield the evaporation rate, interfacial mole fractions, concentration profiles in the gas and liquid phases, and the location of the evaporation front. The analysis can be used to provide the binary liquid diffusion coefficient of the volatile component based on experimental data for the liquid gas interface position as a function of time. The requirements for such a measurement are discussed in terms of the volatility of the evaporating component and its initial concentration in the liquid mixture.[Figure not available: see fulltext.

2006-01-01

159

The Italian survey as the basis of the national radon policy  

Energy Technology Data Exchange (ETDEWEB)

One of the most important goals of the Italian survey, initiated in 1989, was to promote ad hoc policies to reduce radon exposure of the population. In the survey a statistical representative sample of 5000 dwellings was chosen; two six-month measurements were made of the indoor radon concentration, in combination with one six-month measurement of gamma exposure. The results of the radon concentration measurements are reported here: they refer to 80% of the sample. The annual mean value was 81.5Bq.m{sup -3}, which is higher than that reported for other industrialised countries. (author).

1994-12-31

160

Temporary endovascular control of a bleeding aortoenteric fistula by transcatheter coil embolization.  

Science.gov (United States)

A 67-year-old man presented with gastrointestinal bleeding resulting from a fistula between the aortic stump and the fourth part of the duodenum 14 months after an axillobifemoral bypass, graft excision, and aortic stump closure for aortic graft infection. The patient initially refused any attempt at definitive surgical treatment so coil embolization of the aortic stump was performed via a brachial approach. Coil embolization may be a useful adjunct in the management of such difficult problems. This approach may buy time and allow careful planning of a definitive treatment or may serve as a palliative procedure in inoperable patients. PMID:15947052

2005-06-01

161

Studies on technology improvement in the production of iodine and bromine  

International Nuclear Information System (INIS)

Results of studies dealing with improvement of the currently employed technology of iodine and bromine production by processing iodine- and bromine-containing borehole effluent water were considered. Potentiality of selective oxidation of iodide-ions in the presence of bromide-ions in acidified borehole effluent water with addition of ozone for initiating oxidation of iodide-ions and iron(2) salt to prevent bromine evolution was confirmed experimentally. Conditions were determined that rule out bromine formation in the solution, but simultaneously permit varying the yield of iodine within 70-100%

2001-07-01

162

Strong Convergence towards homogeneous cooling states for dissipative Maxwell models  

CERN Document Server

We show the propagation of regularity, uniformly in time, for the scaled solutions of the inelastic Maxwell model for small inelasticity. This result together with the weak convergence towards the homogenous cooling state present in the literature implies the strong convergence in Sobolev norms and in the $L^1$ norm towards it depending on the regularity of the initial data. The strategy of the proof is based on a precise control of the growth of the Fisher information for the inelastic Boltzmann equation. Moreover, as an application we obtain a bound in the $L^1$ distance between the homogeneous cooling state and the corresponding Maxwellian distribution vanishing as the inelasticity goes to zero.

2008-01-01

163

Response to 'Comment on 'Experimental observation of carbon dioxide reduction in exhaust gas from hydrocarbon fuel burning'' [Phys. Plasmas 17, 014701 (2010)  

International Nuclear Information System (INIS)

A high-voltage cathode initiates an electron emission, resulting in a reduction in the carbon dioxide concentration in exhaust gas from the burning of hydrocarbon fuel. Assuming that the observed carbon dioxide reduction is originated from the molecular decomposition, the energy needed for the endothermic reaction of this carbon dioxide reduction may stem primarily from the internal energy reduction in the exhaust gas in accordance of the first law of the thermodynamics. An oxygen increase due to the reduction in carbon dioxide in a discharge gas was observed in real time.

2010-01-01

164

Remote handling and robotics at the BNFL Sellafield reprocessing plant  

International Nuclear Information System (INIS)

As a direct result of its interest in the use of robotics within active plants, British Nuclear Fuels Ltd. (BNFL) has adopted a positive attitude toward both national and European initiatives in this area. During the early operation of the Sellafield reprocessing plant, the process vessels and cell voids were monitored using simple pole and camera combinations. In 1985, BNFL embarked on the provision of a series of machines intended to satisfy the advancing needs for inspection while increasing the level of expertise within the company in this important area. DIMAN 1, DIMAN 2, RODMAN, REPMAN, and RAFFMAN remote handling and robotic machines are described.

1990-11-11

165

Rapid vegetative propagation of conifers  

Energy Technology Data Exchange (ETDEWEB)

Factors influencing the rooting-potential of stem cuttings of conifers were studied for the purpose of improving methods of rapid vegetative propagation. Within the bounds of hereditary limits, root regeneration depends, to a considerable extent, on the qualities of rooting-media, date of cutting excision, age and physiological conditions of the stock plant, age of the cutting-wood, its position on the plant, and chemical treatment. Hardwood cuttings, which have a relatively high content of endogenous auxin and carbohydrates, and morphological root initials, gave the best results. This method made it possible to increase the growth rate of cuttings 2.5-5 times that of cuttings taken from shoots of current growth. (Refs. 21).

1981-04-01

166

Pricing and hedging of derivatives based on non-tradable underlyings  

CERN Document Server

This paper is concerned with the study of insurance related derivatives on financial markets that are based on non-tradable underlyings, but are correlated with tradable assets. We calculate exponential utility-based indifference prices, and corresponding derivative hedges. We use the fact that they can be represented in terms of solutions of forward-backward stochastic differential equations (FBSDE) with quadratic growth generators. We derive the Markov property of such FBSDE and generalize results on the differentiability relative to the initial value of their forward components. In this case the optimal hedge can be represented by the price gradient multiplied with the correlation coefficient. This way we obtain a generalization of the classical 'delta hedge' in complete markets.

2007-01-01

167

Pitting corrosion of zirconium and hafnium  

Energy Technology Data Exchange (ETDEWEB)

The initiation and inhibition of pitting corrosion on zirconium and hafnium in aqueous solutions have been investigated by potentiodynamic, potentiostatic and galvanostatic measurements at 25/sup 0/C. Effects of Cl/sup -/, Br/sup -/and I/sup -/ have been examined over a range of salt concentrations and pH. All three halide ions cause pitting attack on the two metals, but this may be inhibited by other anions. The results show that hafnium is more easily protected against pitting than is zirconium. The data are treated by the Butler-Volmer equation to yield more information about the mechanisms of the pitting corrosion.

1988-02-01

168

Parameter optimization of a planar BEGe detector using Monte Carlo simulations  

International Nuclear Information System (INIS)

This work reports on the use of three state-of-the-art Monte Carlo codes (MCNPX, PENELOPE, FLUKA) in the efficiency calibration of a Broad-Energy Germanium (BEGe) detector. Initial discrepancies found between the experimental and computational efficiency values are related to the poor knowledge of some physical parameters of the detector (dead-layers, crystal dimensions, etc.). As a consequence, a sensitivity analysis was carried out. Each parameter was systematically analyzed, and an accurate model of the detector was determined. The obtained results are consistent, allowing this model to be used in computational efficiency calibrations of the equipment at stake.

2010-11-21

169

Operational status of the Brookhaven National Laboratory Accelerator Test Facility  

International Nuclear Information System (INIS)

Initial design parameters and early operational results of a 50 MeV high brightness electron linear accelerator are described. The system utilizes a radio frequency electron gun operating at a frequency of 2.856 GHz and a nominal output energy of 4.5 MeV followed by two, 2#pi#/3 mode, disc loaded, traveling wave accelerating sections. The gun cathode is photo excited with short (6 psec) laser pulses giving design peak currents of a few hundred amperes. The system will be utilized to carry out infra-red FEL studies and investigation of new high gradient accelerating structures.

1990-06-11

170

On the stability of the Einstein static universe  

Energy Technology Data Exchange (ETDEWEB)

We show using covariant techniques that the Einstein static universe containing a perfect fluid is always neutrally stable against small inhomogeneous vector and tensor perturbations and neutrally stable against adiabatic scalar density inhomogeneities so long as c{sup 2}{sub s} > 1/5, and unstable otherwise. We also show that the stability is not significantly changed by the presence of a self-interacting scalar field source, but we find that spatially homogeneous Bianchi type IX modes destabilize an Einstein static universe. The implications of these results for the initial state of the universe and its pre-inflationary evolution are also discussed. (letter to the editor)

2003-06-07

171

On the stability of the Einstein static universe  

International Nuclear Information System (INIS)

We show using covariant techniques that the Einstein static universe containing a perfect fluid is always neutrally stable against small inhomogeneous vector and tensor perturbations and neutrally stable against adiabatic scalar density inhomogeneities so long as c"2_s > 1/5, and unstable otherwise. We also show that the stability is not significantly changed by the presence of a self-interacting scalar field source, but we find that spatially homogeneous Bianchi type IX modes destabilize an Einstein static universe. The implications of these results for the initial state of the universe and its pre-inflationary evolution are also discussed. (letter to the editor)

2003-06-07

172

On the 2D Cahn-Hilliard equation with inertial term  

CERN Document Server

P. Galenko et al. proposed a modified Cahn-Hilliard equation to model rapid spinodal decomposition in non-equilibrium phase separation processes. This equation contains an inertial term which causes the loss of any regularizing effect on the solutions. Here we consider an initial and boundary value problem for this equation in a two-dimensional bounded domain. We prove a number of results related to well-posedness and large time behavior of solutions. In particular, we analyze the existence of bounded absorbing sets in two different phase spaces and, correspondingly, we establish the existence of the global attractor. We also demonstrate the existence of an exponential attractor.

2008-01-01

173

Multilayer ultra high gradient insulator technology  

Energy Technology Data Exchange (ETDEWEB)

We are investigating a novel insulator concept which involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform many times better (about 1.5 to 4 times higher breakdown electric field) than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present our ongoing studies investigating the degradation of the breakdown electric field resulting from surface roughness, the effect of gas pressure, and the performance of the insulator structure under bi-polar stress. Further, we present our initial modeling studies.

1998-03-27

174

Measurement error modeling and nutritional epidemiology association analyses  

British Library Electronic Table of Contents (United Kingdom)

Abstract This article summarizes the results of a Nutrient Biomarker Study in the Women's Health Initiative, and its application to studies of the association between energy and protein consumption and the risk of major cancers and cardiovascular diseases. The presentation emphasizes measurement error modeling and related data analysis methods, since addressing measurement issues appears to be central to these topics and to progress in nutritional epidemiology more generally. The manner in which body mass index is modeled in disease association analysis is particularly challenging, since it could serve as a mediator or as a confounder of the association, and at the same time contributes valuably to energy and protein consumption assessment. A hazard ratio parameter estimation procedure tha...

2011-01-01

175

Lossless Coding with Generalised Criteria  

CERN Document Server

This paper presents prefix codes which minimize various criteria constructed as a convex combination of maximum codeword length and average codeword length or maximum redundancy and average redundancy, including a convex combination of the average of an exponential function of the codeword length and the average redundancy. This framework encompasses as a special case several criteria previously investigated in the literature, while relations to universal coding is discussed. The coding algorithm derived is parametric resulting in re-adjusting the initial source probabilities via a weighted probability vector according to a merging rule. The level of desirable merging has implication in applications where the maximum codeword length is bounded.

2011-01-01

176

Ion beam crystallography of metal-silicon interfaces: Pd-Si(111)  

Energy Technology Data Exchange (ETDEWEB)

The application of medium energy ion scattering in combination with channelling and blocking to the study of the initial stages of palladium silicide formation is discussed. After a brief description of the experimental arrangement and method, the effects on the Rutherford backscattering spectra of depositing small quantities of palladium on clean Si(111) are reported. The uniformity and thermal stability of thin palladium silicide films grown at room temperature were measured. Finally, channelling and blocking results were used to carry out a structural analysis of thin epitaxial Pd/sub 2/Si layers.

1982-07-09

177

Ion beam crystallography of metal-silicon interfaces: Pd-Si(111)  

International Nuclear Information System (INIS)

The application of medium energy ion scattering in combination with channelling and blocking to the study of the initial stages of palladium silicide formation is discussed. After a brief description of the experimental arrangement and method, the effects on the Rutherford backscattering spectra of depositing small quantities of palladium on clean Si(111) are reported. The uniformity and thermal stability of thin palladium silicide films grown at room temperature were measured. Finally, channelling and blocking results were used to carry out a structural analysis of thin epitaxial Pd_2Si layers. (Auth.).

178

Initial electron-beam characterizations for the Los Alamos APEX Facility  

Energy Technology Data Exchange (ETDEWEB)

The ongoing upgrade of the Los Alamos Free-Electron Laser (FEL) Facility involves the addition of a photoelectric injector (PEI) and acceleration capability to about 40 MeV. The electron-beam and high-speed diagnostics provide key measurements of charge, beam position and profile, divergence emittance, energy (centroid, spread, slew, and extraction efficiency), micropulse duration, and phase stability. Preliminary results on the facility include optical transition radiation interferometer measurements of divergence (1 to 2 mrad), FEL extraction efficiency (0.6 {plus minus} 0.2%), and drive laser phase stability (< 2 ps (rms)). 10 refs.

1991-01-01

179

Initial electron-beam characterizations for the Los Alamos APEX Facility  

Energy Technology Data Exchange (ETDEWEB)

The ongoing upgrade of the Los Alamos Free-Electron Laser (FEL) Facility involves the addition of a photoelectric injector (PEI) and acceleration capability to about 40 MeV. The electron-beam and high-speed diagnostics provide key measurements of charge, beam position and profile, divergence emittance, energy (centroid, spread, slew, and extraction efficiency), micropulse duration, and phase stability. Preliminary results on the facility include optical transition radiation interferometer measurements of divergence (1 to 2 mrad), FEL extraction efficiency (0.6 {plus_minus} 0.2%), and drive laser phase stability (< 2 ps [rms]). 10 refs.

1991-12-31

180

Indirect stabilization of weakly coupled systems with hybrid boundary conditions  

CERN Document Server

We investigate stability properties of indirectly damped systems of evolution equations in Hilbert spaces, under new compatibility assumptions. We prove polynomial decay for the energy of solutions and optimize our results by interpolation techniques, obtaining a full range of power-like decay rates. In particular, we give explicit estimates with respect to the initial data. We discuss several applications to hyperbolic systems with {\\em hybrid} boundary conditions, including the coupling of two wave equations subject to Dirichlet and Robin type boundary conditions, respectively.

2011-01-01

181

Generation of microwaves and hard X-rays in a flash X-ray tube  

Energy Technology Data Exchange (ETDEWEB)

High interelectrode voltage peaks have been observed simultaneously with the emission of hard X-ray bursts from a flash X-ray tube. The magnitude of the voltage peaks may exceed twice the initial charging voltage. It has also been observed that the discharge emits bursts of X-and P-band microwaves radiation which are coincident with the emission of the hard X-ray bursts. The results indicate that the microwaves and X-rays have a common origin in discharge plasma movements and an acceleration model for electrons in the plasma is presented as one possible explanation of the observed phenomena.

1982-01-01

182

Feynman scaling violation due to baryon number diffusion in rapidity space  

CERN Document Server

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of a baryon charge diffusion in rapidity space. Evidently, such a diffusion should decrease the baryon charge in the fragmentation region leading to the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. We present the quantitative predictions for the Feynman scaling violation at LHC energies and even at highier energies that can be important for cosmic ray physics.

2011-01-01

183

Experimental Study of Plasma-Surface Interaction and Material Damage Relevant to ITER Type I Elms  

International Nuclear Information System (INIS)

The paper presents experimental investigations of main features of plasma surface interaction and energy transfer to the material surface in dependence on plasma heat loads. The experiments were performed with QSPA repetitive plasma pulses of the duration of 0.25 ms and the energy density up to 2.5 MJ/m2. Surface morphology of the targets exposed to QSPA plasma screams is analyzed. Relative contribution of the Lorentz force and plasma pressure gradient to the resulting surface profile is discussed. development of cracking on the tungsten surface and swelling of the surface are found to be in strong dependence on initial temperature of the target.

2006-01-01

184

Evaluation of aged concrete structures for continued service in nuclear power plants  

International Nuclear Information System (INIS)

Results are summarized of a study on concrete component aging and its significance relative to continued service of nuclear power plants (NPPs) beyond the initial period for which they were granted operating licenses. Progress is presented of a second study being conducted to identify and provide acceptance criteria for structural safety issues which the USNRC staff will need to address when applications are submitted for continued service of NPPs. Major activities under this program include: development of a materials property data base, establishment of structural component assessment and repair procedures, and development of a methodology for determination of structural reliability. 19 refs., 5 figs., 3 tabs.

1988-10-24

185

European Space Power Conference  

International Nuclear Information System (INIS)

To support the Space Exploration Initiative (SEI), a study was performed to investigate power system alternatives for the rover vehicles and servicers that were subsequently generated for each of these rovers and servicers, candidate power sources incorporating various power generation and energy storage technologies were identified. The technologies were those believed most appropriate to the SEI missions, and included solar, electrochemical, and isotope systems. The candidates were characterized with respect to system mass, deployed area, and volume. For each of the missions a preliminary selection was made. Results of this study depict the available power sources in light of mission requirements as they are currently defined.

1991-09-02

186

Dextranomer/hyaluronic acid copolymer (Deflux) implants mimicking distal ureteral calculi on CT  

Energy Technology Data Exchange (ETDEWEB)

Periureteral or subtrigonal injection of dextranomer/hyaluronic acid (Dx/HA) copolymer (Deflux, Q-Med, Uppsala, Sweden) is an increasingly common endoscopic treatment for vesicoureteral reflux. We report a confusing radiographic finding of bilateral calcified Dx/HA injections initially thought to represent bilateral distal ureteral stones in a boy who presented with intermittent periumbilical pain. Urologists, radiologists, and emergency room physicians should be aware of the potential for calcification of ureteral implants of Dx/HA, and of the potentially confusing radiographic images that may result. (orig.)

2008-01-15

187

Depolarization in the SLC collider arcs  

Energy Technology Data Exchange (ETDEWEB)

In the 1993 running cycle of the Stanford Linear Collider electron spin polarization measurements with a Moller polarimeter at the end of the linac and a Compton polarimeter near the interaction point (IP) indicated a relative polarization loss of up to 20% across the arc. We present calculations of the depolarizing effects where variations in energy, energy spread and transverse emittance as well as changes in orbit and initial spin orientation are taken into account. We compare our results with measurements and conclude that, in standard operating conditions, the relative polarization loss is only 3+/-2%.

1994-06-27

188

Dependence of laser assisted cleaning of clad surfaces on the laser fluence  

International Nuclear Information System (INIS)

The decontamination factor is studied as a function of laser fluence for three kinds of clad surfaces viz., plain zircaloy, autoclaved zircaloy and SS with cesium as the test contamination. It has been found that the decontamination factor exhibits a maximal behaviour with the laser fluence and its maximum value occurs at different laser fluences in the three cases. The maximal behaviour is attributed to reduced coupling of energy from the laser beam to the substrate due to the initiation of surface-assisted optical breakdown. The results obtained in the experiment carried out in helium environment qualitatively support this explanation (author)

2005-11-01

189

Chiral crystallization and the origin of chiral life on earth  

British Library Electronic Table of Contents (United Kingdom)

Abstract The creation of chirality on Earth and the development of chiral life have been discussed in this highlight. Convincing evidence for the introduction of chirality on Earth is still fragmentary. We believe that by a combination of chiral crystallization and formation of helical polymers with preferred chiral conformational structure is the key to this question. This concept of macromolecular asymmetry has inspired ideas and resulted in possible rules for how chiral life as we know it, could have been introduced. These investigations needed the understanding of the requirements for chiral crystallization, for the stereochemistry of the initial formation of helical polymers, the measurements of optical activity of solids and their coordination with the fundamentals of chirality. Spac...

2011-01-01

190

Chalk Point Cooling Tower Project. Environmental systems corporation's comprehensive project status report for FY75, July 1, 1974--October 1, 1975. [Environmental effects of natural draft cooling towers of oil-fired power plant  

Science.gov (United States)

Results are reported from initial characterization tests on the environmental effects of the natural draft cooling tower of the Chalk Point Unit 3 oil-fired power plant located on the shore of Chesapeake Bay. Data are included on updraft air velocity, plume drift, and sea salt deposition in relation to meteorological conditions.

1976-05-01

191

Application of the combined integral method to Stefan problems  

British Library Electronic Table of Contents (United Kingdom)

In this paper we present a new, accurate form of the heat balance integral method, termed the combined integral method (CIM). The application of this method to Stefan problems is discussed. For simple test cases the results are compared with exact and asymptotic limits. In particular, it is shown that the CIM is more accurate than the second order, large Stefan number, perturbation solution for a wide range of Stefan numbers. In the initial examples it is shown that the CIM reduces the standard problem, consisting of a PDE defined over a domain specified by an ODE, to the solution of one or two algebraic equations. The latter examples, where the boundary temperature varies with time, reduce to a set of three first order ODEs.

2011-01-01

192

Analytical solution of tt dilepton equations  

International Nuclear Information System (INIS)

The top quark antiquark production system in the dilepton decay channel is described by a set of equations which is nonlinear in the unknown neutrino momenta. Its most precise and least time consuming solution is of major importance for measurements of top quark properties like the top quark mass and tt spin correlations. The initial system of equations can be transformed into two polynomial equations with two unknowns by means of elementary algebraic operations. These two polynomials of multidegree two can be reduced to one univariate polynomial of degree four by means of resultants. The obtained quartic equation is solved analytically.

2006-03-01

193

AFS Cupola Model Verification--Initial Investigations  

Science.gov (United States)

The cupola furnace is used to melt scrap steel, pig iron, foundry returns, and alloying additives to a prescribed tapping chemistry and temperature for iron casting applications. The melting process within the cupola is highly complex and not well quantified. The American Foundrymen's Society is developing a mathematical model to aid in the understanding of these processes. This model is reaching maturity, and has been successful in estimating a number of melting parameters. This paper details the results of efforts to verify the model in a controlled system, equipped wit the appropriate sensors, for model verification. The work was performed on a research-scale cupola furnace located at the Department of Energy's Albany Research Center.

1998-01-01

194

A method for locating where the real part of the Riemann zeta function becomes negative for its real argument greater than one  

CERN Document Server

This paper describes a search algorithm to locate values of t where the real part of the Riemann zeta function, zeta(sigma+it), is negative for sigma>1. The run-time to execute the search is much less than a brute-force approach and relies on certain symmetries of congruence equations related to the zeta function. Initial results show the smallest value of t where this begins to occur is much nearer to the real axis than conservative estimates would suggest.

2010-01-01

195

Spiral Structures and Shocks in Accretion Discs in Close Binary Systems: the Role of the Injection Velocity at the Inner Lagrangian Point  

Science.gov (United States)

In our previous paper (Lanzafame et al. 2000, PASJ 52, 515) we showed, through 2D SPH simulations, that the stellar mass ratio, M 2 / M 1, of a close binary system (that determines the position and then the initial specific angular momentum at L 1) plays a fundamental role in the formation and development of spiral structures and shock fronts in the radial flow of accretion discs. In that work only a quasi-sonic value of the injection velocity at L 1 was considered. In the present work we also carried out 2D SPH simulations with the aim to investigate the development of such structures, while keeping constant the mass of the compact primary (M 1 = 1 M odot) and the separation between the two components, and assuming as an initial condition of two different supersonic injection velocities at L 1, characterizing two sets of simulations. For each set we considered four values of the secondary to primary mass ratio, M 2 / M 1. We worked out 2D ...

2001-02-01

196

Relic abundance of WIMPs in non-standard cosmological scenarios  

Energy Technology Data Exchange (ETDEWEB)

In this thesis we study the relic density n{sub {chi}} of non--relativistic long--lived or stable particles {chi} in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles {chi} to achieve full chemical equilibrium. We also investigated the case where {chi} particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T{sub 0} of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the {chi} number ...

2007-08-06

197

Emplacement ages of Jurassic-Cretaceous South African kimberlites by the Rb-Sr method on phlogopite and whole-rock samples  

International Nuclear Information System (INIS)

Rb-Sr phlogopite age determinations, interpreted as emplacement ages, are reported for 15 southern African kimberlites. Jagersfontein and Rietfontein (85 and 95 Ma) have ages typical of the majority of well-known Cretaceous kimberlites, whereas somewhat older ages of about 118 to 125 Ma have been obtained for localities in the Postmasburg, Barkly West and Boshoff districts. Previous zircon ages of 90Ma for Finsch and Roberts Victor are believed to be incorrect. Two other localities in the Barkly West area have significantly younger emplacement ages of about 114 Ma relative to most Barkly West occurrences. Two off-craton kimberlites, Uintjiesberg and Mzongwana, are 100 and 150 Ma in age respectively. Swartruggens and Elandskloof have ages of 150-160 and 165 Ma respectively. A Barkly West occurrence, Klipfontein, also has an apparent age of 160 Ma, but this result cannot be considered reliable. The emplacement ages and initial "8"7Sr/"8"6Sr ...

198

Characterization of the corrosion behavior of the carbon steel liner in Hanford Site single-shell tanks  

Energy Technology Data Exchange (ETDEWEB)

Six safety initiatives have been identified for accelerating the resolution of waste tank safety issues and closure of unreviewed safety questions. Safety Initiative 5 is to reduce safety and environmental risk from tank leaks. Item d of Safety Initiative 5 is to complete corrosion studies of single-shell tanks to determine failure mechanisms and corrosion control options to minimize further degradation by June 1994. This report has been prepared to fulfill Safety Initiative 5, Item d. The corrosion mechanisms that apply to Hanford Site single-shell tanks are stress corrosion cracking, pitting/crevice corrosion, uniform corrosion, hydrogen embrittlement, and microbiologically influenced corrosion. The corrosion data relevant to the single-shell tanks dates back three decades, when results were obtained from in-situ corrosion coupons in a few single-shell tanks. Since that time there ...

1994-06-01

199

Characterization of detonator performance using photonic Doppler velocimetry  

Science.gov (United States)

Detonators are used to convert electrical or other energy into an explosive output. This output can then be used to initiate further explosive charges. To aid in the development of explosive systems, it is important to characterize the output of detonators, in particularly the pressure produced. Recent advances over the last five years in high-speed digitizing oscilloscopes and high-bandwidth photodiodes, driven primarily by the telecommunications industry, have enabled the development of a new type of interferometer for measuring high velocities, such as those found in detonics experiments. The Photonic Doppler Velocimeter (PDV) can be visualized as a fiber-based Michelson interferometer. The light from a single-mode fiber laser at 1550 nm is passed through a circulator, which acts to separate bi-directional light. The beam is then reflected via free-space optics off the surface of interest, and then focused back into the same fiber. This reflected light is then ...

2008-08-01

200

A review of initiatives to reduce energy-related CO_2 emissions from the city of Oxford: past, present and future  

International Nuclear Information System (INIS)

This paper reviews three key initiatives undertaken in the historical city of Oxford to bring about reductions in energy-related CO_2 emissions on a city-wide scale. The author has been part of all the three initiatives. In 2002, a collaborative partnership between academia, industry and city council started the Oxford Solar Initiative (OSI) which uses a community-based approach to help households and organisations in Oxford, financially and technically, to install solar energy systems and energy efficiency measures in buildings. So far OSI has facilitated the installation of 80 active solar systems, over 450 energy efficiency measures and 3,000 low energy bulbs. The scientific basis of OSI is a GIS-based DECoRuM model which estimates and maps baseline energy use and CO_2 emissions on a house-by house level, identifies 'pollution' hotspots, predicts the potential for reductions in CO_2 emissions and monitors reductions ...

2007-06-04

201

Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction (TOPCARE-AMI): final 5-year results suggest long-term safety and efficacy  

British Library Electronic Table of Contents (United Kingdom)

Background Limited data is available for investigating the long-term safety and effects of intracoronary progenitor cell therapy in patients with acute myocardial infarction (AMI). Objective To assess the clinical course, NT-proBNP and MRI data as objective markers of cardiac function of the TOPCARE-AMI patients at 5-year follow-up. Design The TOPCARE-AMI trial was the first randomized study investigating the effects of intracoronary infusion of circulating (CPC) or bone marrow-derived progenitor cells (BMC) in 59 patients with successfully reperfused AMI. Results Five-year follow-up data were completed in 55 patients, 3 patients were lost to follow-up. None of the patients showed any signs of intramyocardial calcification or tumors at 5?years. One patient died during the initial hospitali...

2011-01-01

202

The assessment of defects in thin shells subject to secondary stress  

International Nuclear Information System (INIS)

This paper is concerned with the fracture analysis of thin cylindrical shells subject to secondary bending stresses with some degree of elastic follow-up. A P.Y.F.M. failure assessment route is utilised for an initial investigation. Results are presented graphically and indicate the differences obtained by considering the stresses as primary or secondary in nature. The Jsup(*) contour integral is computed from the results of a non-linear finite element analysis of a thermally loaded cracked cylinder. Comparison is made between Jsup(*) and the P.Y.F.M. failure criteria demonstrating the degree of conservatism in the latter. It is observed that LEFM may be appropriate for moderate load levels but that the elastic follow-up of the structure causes enhancement of Jsup(*) for higher loads, at which stage LEFM becomes non-conservative. (orig.).

1981-08-21

203

Study on fracture behaviour of Al?15%Mg2Si metal matrix composite with and without beryllium additions  

British Library Electronic Table of Contents (United Kingdom)

In this study, the influence of Beryllium (Be) content on the fracture behaviour of Al?15%Mg2Si composite was investigated. The results showed an increase in mechanical properties with increasing of Be content. The stress?strain curves of samples showed a same category of serrations reflecting non-uniform deformation. Scanning electron microscopy was employed to examine the crack nucleation and fracture model. The results indicate that Al?15%Mg2Si composite shows different behaviours of crack initiation and fracture for samples with and without Be. Differences observed in the fracture behaviour were attributed to microstructural changes as well as morphological aspects of primary Mg2Si particles.

2011-01-01

204

Results of cycling with battery charging management; Resultats de cyclage avec gestion de charge au niveau batterie  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the charging mode of an in-series assembly of lithium-carbon battery cells, a test has been performed on 5 commercial cells (18650) of 0.95 Ah nominal capacity. Results show that it is possible to cycle the cells at 80% of their output capacities during more than 2000 cycles. The management of the battery consists in maintaining a constant battery voltage as soon as a cell reaches its limit voltage during constant current charging. The initial dispersion of cells has been maintained practically constant during the cycling and the charge state of all cells has decreased progressively. (J.S.)

1996-12-31

205

Radiation processing of fibre-reinforced composites  

International Nuclear Information System (INIS)

Electron beam (EB) processing involves using electrons to initiate polymerization or cross-linking reactions in suitable substrates, thereby enhancing specific physical and chemical properties. A relatively new use of EB processing is now emerging: the production of fibre-reinforced composites. EB curing at ambient temperature has the potential to reduce the residual stresses in an advanced composite, a result of expansion during thermal curing, and to significantly increase the overall cure speed and process throughput. Wood fibres are used as a filler material for various thermoplastics such as polypropylene. EB treatment, combined with selected EB-curable coupling agents, significantly increases the adhesion between the wood fibres and the thermoplastic polymer, resulting in improved material properties. Work to develop both products and processes for the EB curing of fibre-reinforced composites is currently underway at ...

1991-06-09

206

Pitting corrosion of stainless steels; Lochkorrosion an nichtrostenden Staehlen  

Energy Technology Data Exchange (ETDEWEB)

Stainless steels can get pitting corrosion in halide containing solution, which make them a big risk in industrial production. Many investigations were made in the past in order to understand processes involved in pitting corrosion, pit initiation and pit growth. Results about the influence of alloying elements, their contents, the state of the structure, the condition of the surface, the content of chloride, the temperature, the pH-value, the velocity of flow and of the oxidizer on the chloride induced pitting corrosion of passive stainless steels are presented. Electrochemical measurements and the application of surface analytical methods (SEM, SAM, XPS) with high lateral resolution are carried out. A part of the samples received a diffusion annealing in order to obtain reproducible results. Pitting Resistance Equivalents (PRE) - Pitting Index - with different multipliers are given and discussed critical. An ...

1996-01-01

207

Personal nuclear accident dosimetry at Sandia National Laboratories  

Energy Technology Data Exchange (ETDEWEB)

DOE installations possessing sufficient quantities of fissile material to potentially constitute a critical mass, such that the excessive exposure of personnel to radiation from a nuclear accident is possible, are required to provide nuclear accident dosimetry services. This document describes the personal nuclear accident dosimeter (PNAD) used by SNL and prescribes methodologies to initially screen, and to process PNAD results. In addition, this report describes PNAD dosimetry results obtained during the Nuclear Accident Dosimeter Intercomparison Study (NAD23), held during 12-16 June 1995, at Los Alamos National Laboratories. Biases for reported neutron doses ranged from -6% to +36% with an average bias of +12%.

1996-09-01

208

New Permeameters for In Situ Characterization of Unsaturated Heterogeneous Permeability: Development, Design, Testing, and Application  

Energy Technology Data Exchange (ETDEWEB)

The original objective of our EMSP research was to design, develop, and test new in situ field permeameters for use in spatial variability studies of unsaturated hydraulic properties. We initially focused on activities related to development and testing of techniques for inverting permeameter data, development of numerical tools for data inversion, error evaluation for permeameter design, and permeameter component design. However, the results of error evaluations for permeameter design caused us to redirect our research, and reformulate our research objectives. We discovered that small, simple measurement errors lead to significant bias in the estimated hydraulic properties and their spatial statistics. Our reformulated research objective became the evaluation of the origin, impact and relevance of spatial bias in field-and laboratory-estimated unsaturate hydraulic properties, with an emphasis on spatial statistics and the ...

2001-12-01

209

Modeling of Anisotropic Inelastic Behavior  

Energy Technology Data Exchange (ETDEWEB)

An experimental capability, developed at Lawrence Livermore National Laboratory (LLNL), is being used to study the yield behavior of elastic-plastic materials. The objective of our research is to develop better constitutive equations for polycrystalline metals. We are experimentally determining the multidimensional yield surface of the material, both in its initial state and as it evolves during large inelastic deformations. These experiments provide a more complete picture of material behavior than can be obtained from traditional uniaxial tests. Experimental results show that actual material response can differ significantly from that predicted by simple idealized models. These results are being used to develop improved constitutive models of anisotropic plasticity for use in continuum computer codes.

2000-02-25

210

MODELING AN ION EXCHANGE PROCESS FOR CESIUM REMOVAL FROM ALKALINE RADIOACTIVE WASTE SOLUTIONS  

Energy Technology Data Exchange (ETDEWEB)

The performance of spherical Resorcinol-Formaldehyde ion-exchange resin for the removal of cesium from alkaline radioactive waste solutions has been investigated through computer modeling. Cesium adsorption isotherms were obtained by fitting experimental data using a thermodynamic framework. Results show that ion-exchange is an efficient method for cesium removal from highly alkaline radioactive waste solutions. On average, two 1300 liter columns operating in series are able to treat 690,000 liters of waste with an initial cesium concentration of 0.09 mM in 11 days achieving a decontamination factor of over 50,000. The study also tested the sensitivity of ion-exchange column performance to variations in flow rate, temperature and column dimensions. Modeling results can be used to optimize design of the ion exchange system.

2008-08-26

211

Increased capability of Strassy: the decision making aid for the inspection of nuclear materials; Prolongement des capacites de Strassy: systeme d`aide a la decision pour le controle des matieres nucleaires  

Energy Technology Data Exchange (ETDEWEB)

The paper describes the latest developments in STRASSY (Strategy Assistance System), the strategy assistance system for the inspection of nuclear materials. The user can now select the fuel cycle he wishes to investigate from an initial range of 19 facilities. An inspection interface has been developed to enable the details and dates of inspections to be modified. One of the special features of the application of STRASSY in international safeguards is the taking into account of timeliness of detection; certain aspects of the time manager algorithms are presented and analysed, including the guaranteed existence of a solution. The results of a study of diversion paths in a simplified cycle consisting of our facilities are presented. Finally, the modifications necessary to enable STRASSY to be used for a posterior analysis of inspection results are discussed. (authors). 7 refs., 3 figs.

1994-12-31

212

Field Generation and Dissipation Currents in Thunderclouds as a Result of the Movement of Charged Hydrometeors.  

Science.gov (United States)

The calculations of Gay et al. of the terminal velocities of charged hydrormeteors in the presence of electric fields have formed the basis of computations of the charging current density J flowing through a thunder-cloud as a result of the operation of a precipitative mechanism of cloud electrification. Values of J were calculated for a range of values of field strength E, precipitation rate pO, precipitation content L, cloud water content C, charge distribution, total separated charge, and the fraction of the small particles that have undergone a charging event.It is found that the estimated field required for the initiation of a lightning stroke (3.5 kV cm1 can be achieved only over a narrow range of conditions. The ease with which precipitative mechanisms can produce breakdown fields is considerably increased, however, if account is taken of spatial inhomogenities in the field.

1975-05-01

213

FY2000 Annual Self-Evaluation Report for the Pacific Northwest National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

This self-evaluation report offers a summary of results from FY2000 actions to achieve Pacific Northwest National Laboratory's strategy and provides an analysis of the state of their self-assessment process. The result of their integrated planning and assessment process identifies Laboratory strengths and opportunities for improvement. Critical elements of that process are included in this report; namely, a high-level summary of external oversight activities, progress against Operations Improvement Initiatives, and a summary of Laboratory strengths and areas for improvement developed by management from across the laboratory. Some key areas targeted for improvement in FY2001 are: systems approach to resource management; information protection; integrated safety management flow-down to the benchtop; cost management; integrated assessment; Price Anderson Amendments Act (PAAA) Program; and travel risk mitigation.

2000-11-15

214

Development of Point Arguello field, offshore California  

Energy Technology Data Exchange (ETDEWEB)

Development drilling from Chevron-operated Platform Hermosa, located on OCS-P 0316 of the Point Arguello field, began on January 30, 1987. To date, seven development wells have been drilled in to the northwest-southeast-trending, doubly plunging anticlinal structure. The results from drilling have confirmed the presence of intense folding and fracturing in the targeted Monterey Formation. Over 700 ft of conventional core were recovered from the B-2 well in the lower Sisquoc and Monterey Formations. Analysis of the core material has yielded important information on lithologic variations and fracture patterns in the productive Monterey Formation. Initial results of core studies, DST data, and wireline studies indicate a correlation between rock type and fracturing. Fracture trends and directional permeability suggested by drill-stem testing may affect future drilling patterns in the field.

1988-03-01

215

CERT tribal internship program. Final intern report: Karen Sandoval, 1994  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the project was to: create a working relationship between CERT and Colorado State University (CSU); involve and create relationships among individuals and departments at CSU; empower Native communities to run their own affairs; establish programs for the benefit of Tribes; and create Native American Program Development Office at CSU. The intern lists the following as the project results: revised a Native American Program Development document; confirmation from 45 departments across campus for Summit attendance [Tribal Human Resource Development Summit]; created initial invitee list from CSU departments and colleges; and informed CERT and CSU staff of results. Much of the response from the campus community has been positive and enthusiastic. They are ready to develop new Native American programs on campus, but need the awareness of what they can do to be respectful of Tribal needs.

1998-09-01

216

Behavioral Momentum during a Continuous Reading Task: An Exploratory Study  

Science.gov (United States)

Adolescents with emotional and behavioral disorders (EBD) often fail to master literacy skills, in part because disruptive behaviors interfere with task engagement and persistence. The theory of behavioral momentum explains the persistence of behavior in the face of changing environmental conditions. The current exploratory study examined variables related to behavioral momentum in the context of a continuous reading task. Participants were three adolescents identified with EBD who were instructional on fifth-grade material. Results indicated that when participants read a third-grade paragraph immediately before a fifth-grade paragraph, they decreased the latency to initiate reading of the fifth-grade paragraph and increased words read correctly per minute on the first 10 words of the fifth-grade paragraph. Results are discussed in terms of the theory of behavioral momentum and the nature of interventions that may be ...

2011-09-01

217

An analytical study on excitation of nuclear-coupled thermal hydraulic instability due to seismically induced resonance in BWR  

Energy Technology Data Exchange (ETDEWEB)

A core-wide in-phase neutron flux oscillation, which took place, for example, at LaSalle-2 in the USA in 1988, is one of the nuclear-coupled thermal hydraulic instabilities in boiling water reactors (BWRs). In this study, an analysis has been performed focusing on the excitation of this type of instability in BWRs due to seismically induced resonance, within the scope of a point kinetics model. For this purpose, the TRAC-BF1 code has been modified to take into account the external acceleration in addition to gravity. As a result of this analysis, it is shown that reactivity insertion can occur accompanied by in-surge of the coolant into the core resulting from excitation. It is also shown that the amount of reactivity inserted largely depends on the degree of stability of the initial state and the amplitude of the seismic wave, whose frequency is the same as the characteristic frequency of the instability. (orig.).

1996-04-01

218

An analytical study on excitation of nuclear-coupled thermal hydraulic instability due to seismically induced resonance in BWR  

International Nuclear Information System (INIS)

A core-wide in-phase neutron flux oscillation, which took place, for example, at LaSalle-2 in the USA in 1988, is one of the nuclear-coupled thermal hydraulic instabilities in boiling water reactors (BWRs). In this study, an analysis has been performed focusing on the excitation of this type of instability in BWRs due to seismically induced resonance, within the scope of a point kinetics model. For this purpose, the TRAC-BF1 code has been modified to take into account the external acceleration in addition to gravity. As a result of this analysis, it is shown that reactivity insertion can occur accompanied by in-surge of the coolant into the core resulting from excitation. It is also shown that the amount of reactivity inserted largely depends on the degree of stability of the initial state and the amplitude of the seismic wave, whose frequency is the same as the characteristic frequency of the instability. (orig.).

1996-01-01

219

Adalimumab treatment in Crohn's disease does not induce early changes in regulatory T cells  

British Library Electronic Table of Contents (United Kingdom)

Abstract Objective. Anti-TNF-a antibodies has been suggested to modulate regulatory T cell (Treg) percentages in rheumatoid arthritis, but results from studies of Crohn's disease (CD) are conflicting. We investigated dynamic changes of circulating Tregs in CD during treatment with the anti-TNF-a-antibody adalimumab (Humira, Abbott Laboratories A/S, Emdrupvej 28C, DK-2100 Copenhagen). Material and methods. Blood samples from 26 CD patients were analysed using flow cytometry before and 1 and 26 weeks after initiation of adalimumab treatment to determine the percentage of Tregs among CD4++ T cells. Results. In spite of a significant decline in disease activity scores and biochemical markers of inflammation, during the first week of treatment, we did not observe early modulating effects of ada...

2011-01-01

220

Absorption of carbon dioxide at high partial pressures in 1-amino-2-propanol aqueous solution. Considerations of thermal effects  

Energy Technology Data Exchange (ETDEWEB)

In the present work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA)), in relation to the thermal effects involved. All experiments were made in a stirred-tank reactor with a plane unbroken gas-liquid interface. The variables considered were the MIPA concentration within the range 0.1--2.0 M and the temperature within the interval 288--308 K. From the results, the authors deduce that the absorption process takes place in the nonisothermal instantaneous regime and propose an equation which not only relates the experimental results of flow density with the initial concentration of amine but at the same time enables the evaluation of the rise in temperature in the gas-liquid interface.

1997-10-01

221

Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates  

Energy Technology Data Exchange (ETDEWEB)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, which prevented the internal nitridation typically observed for these alloys, and ...

2007-01-01

222

Protective nitride formation on stainless steel alloys for proton exchange membrane fuel cell bipolar plates  

Energy Technology Data Exchange (ETDEWEB)

Gas nitridation has shown excellent promise to form dense, electrically conductive and corrosion-resistant Cr-nitride surface layers on Ni-Cr base alloys for use as proton exchange membrane fuel cell (PEMFC) bipolar plates. Due to the high cost of nickel, Fe-base bipolar plate alloys are needed to meet the cost targets for many PEMFC applications. Unfortunately, nitridation of Fe-base stainless steel alloys typically leads to internal Cr-nitride precipitation rather than the desired protective surface nitride layer formation, due to the high permeability of nitrogen in these alloys. This paper reports the finding that it is possible to form a continuous, protective Cr-nitride (CrN and Cr{sub 2}N) surface layer through nitridation of Fe-base stainless steel alloys. The key to form a protective Cr-nitride surface layer was found to be the initial formation of oxide during nitridation, which prevented the internal nitridation typically observed for these alloys, and ...

2007-11-22

223

Fuel management optimization in CANDU reactors cooled with light water; Optimisation de la gestion du combustible dans les reacteurs CANDU refroidis a l'eau lege  

Energy Technology Data Exchange (ETDEWEB)

This research has two main goals. First, we wanted to introduce optimization tools in the diffusion code DONJON, mostly for fuel management. The second objective is more practical. The optimization capabilities are applied to the fuel management problem for different CANDU reactors at refueling equilibrium state. Two kinds of approaches are considered and implemented in this study to solve optimization problems in the code DONJON. The first methods are based on gradients and on the quasi-linear mathematical programming. The method initially developed in the code OPTEX is implemented as a reference approach for the gradient based methods. However, this approach has a major drawback. Indeed, the starting point has to be a feasible point. Then, several approaches have been developed to be more general and not limited by the initial point choice. Among the different methods we developed, two were found to be very efficient: the multi-step method ...

2006-07-01

224

Deliberate ignition of hydrogen-air-steam mixtures in condensing steam environments  

Energy Technology Data Exchange (ETDEWEB)

Large scale experiments were performed to determine the effectiveness of thermal glow plug igniters to burn hydrogen in a condensing steam environment due to the presence of water sprays. The experiments were designed to determine if a detonation or accelerated flame could occur in a hydrogen-air-steam mixture which was initially nonflammable due to steam dilution but was rendered flammable by rapid steam condensation due to water sprays. Eleven Hydrogen Igniter Tests were conducted in the test vessel. The vessel was instrumented with pressure transducers, thermocouple rakes, gas grab sample bottles, hydrogen microsensors, and cameras. The vessel contained two prototypic engineered systems: (1) a deliberate hydrogen ignition system and (2) a water spray system. Experiments were conducted under conditions scaled to be nearly prototypic of those expected in Advanced Light Water Reactors (such as the Combustion Engineering (CE) System 80+), with prototypic spray drop ...

1997-05-01

225

A Human reliability analysis of post-accident human errors in the PSA of KSNP  

International Nuclear Information System (INIS)

Korea Atomic Energy Research Institute, using the ASME PRA Standard, evaluated the PSA model of the Korea Standard Nuclear Power Plant (KSNP) and identified the items to be improved to enhance its quality. The new risk monitor PSA model for the KSNP of which quality was enhanced is called as PRiME-U3i. The evaluation results of human reliability analysis (HRA) of the post-accident human errors in the PSA model of the KSNP showed that 10 items among 19 items of supporting requirements for those in the ASME PRA Standard were identified as them to be improved. Thus, we newly carried out a HRA for post-accident human errors for the KSNP PSA model as the target of grading its quality above ASME PRA Standard Category I+. Following tasks were additionally major tasks performed in the HRA of post-accident human errors of PRiME-U3i compared with the previous PSA model of the KSNP: interviews with operators in the collection and review of input data need for the HRA, ...

2004-10-28

226

The Brazilian spherical detector: progress and plans  

International Nuclear Information System (INIS)

We are building the Schenberg gravitational wave detector at the Physics Institute of University of Sao Paulo as programmed by the Brazilian Graviton Project. The antenna and its vibration isolation system are already built, and we have made a first cryogenic run for an overall test, in which we measured the antenna mechanical Q (figure of merit). We also have built a 10.21 GHz oscillator with phase noise performance better than -120 dBc at 3.2 kHz to pump an initial CuAl6% two-mode transducer. We plan to prepare this spherical antenna for a first operational run at 4.2 K with a single transducer and an initial target sensitivity of h #approx# 2 x 10"-"2"1 Hz"-"1"/"2 in a 50 Hz bandwidth around 3.2 kHz soon. Here we present details of this plan and some recent results of the development of this project.

2004-03-07

227

Spiral Structures and Shocks in Accretion Discs in Close Binary Systems: the Role of the Stellar Mass Ratio.  

Science.gov (United States)

% In this work we investigated, in the Smooth Particle Hydrodynamics (SPH) framework, the development of spiral structures and shock fronts in the radial flow of accretion discs in close binary systems. These shock waves take place when the initially supersonic radial flow penetrating the disc bulk, reduces substantially its speed becoming suddenly subsonic. To this purpose, keeping constant the mass of the compact primary (M1 = 1 MO ), the separation between the two components and the injection speed at the inner Lagrangian point L1 (close to the local sound speed), we carried out 2D SPH simulations for four values of the stellar mass ratio M2/M1. We worked out 2D models because the damping effect of the artificial viscosity is too strong in 3D. Furthermore, the 2D environment seems the most suitable in order to evidence shock fronts in highly compressible gases. The results show that spiral structures and shock fronts develop for low values ...

2000-06-01

228

Radionuclide liver and bone scanning in the evaluation of patients with endometrial carcinoma  

International Nuclear Information System (INIS)

Staging bone scans or skeletal surveys were obtained of 97 patients with endometrial carcinoma. Of the 77 patients with Stage I or II disease, no metastases were identified at staging. Three patients in the entire series demonstrated bony metastases; all of these metastases were detectable by radionuclide bone scan and radiographic bone survey. Eighty-nine patients were examined with radionuclide liver/spleen scanning at the time of staging. Four of the 89 initial scans were interpreted as demonstrating hepatocellular disease, and all four patients had abnormal liver function studies. Only one patient demonstrated a possible hepatic metastasis at initial diagnosis. This patient also had abnormal liver function studies. Based on these results, bone surveys and radionuclide bone scans are not indicated as screening procedures in endometrial carcinoma. It is suggested that screening for liver metastases in patients with ...

229

Radiation hardening revisited: role of intracascade clustering  

International Nuclear Information System (INIS)

Experimental observations related to the initiation of plastic deformation in metals and alloys irradiated with fission neutrons have been analyzed. The experimental results, showing irradiation-induced increase in the upper yield stress followed by a yield drop and plastic instability, cannot be explained in terms of conventional dispersed-barrier hardening because (a) the grown-in dislocations are not free, and (b) irradiation-induced defect clusters are not rigid indestructible Orowan obstacles. A new model called 'cascade-induced source hardening' is presented where glissile loops produced directly in cascades are envisaged to decorate the grown-in dislocations so that they cannot act as dislocation sources. The upper yield stress is related to the breakaway stress which is necessary to pull the dislocation away from the clusters/loops decorating it. The magnitude of the breakaway stress has been estimated and is found to be in good ...

230

Radiation decoherence, state vector collapse and QED nonequivalent representations  

CERN Document Server

The state vector evolution in the interaction of initial measured pure state with collective quantum system or the field with a very large number of degrees of freedom N is analysed in a nonperturbative QED formalism. As the example the measurement of the electron final state scattered on nucleus or neutrino is considered.In the nonperturbative field theory the complete manifold of the system states is nonseparable i.e. is described by tensor product of infinitely many independent Hilbert spaces. The interaction of this system with the measured state can result in the final states which belong to different Hilbert spaces which corresponds to different values of some classical observables,i.e. spontaneous symmetry breaking occurs. Interference terms (IT) between such states in the measurement of any Hermitian observable are infinitely small and due to it the final pure states can't be distinguished from the mixed ones, characteristic for the ...

1996-01-01

231

Pilot studies at industrial sources with an electrostatic precipitator having wide plate spacing. Pilotuntersuchungen an industriellen Quellen mit einem elektrischen Abscheider grosser Gassenweite  

Energy Technology Data Exchange (ETDEWEB)

With a pilot electrostatic precipitator having wider plate spacings than usual tests were performed under industrial conditions. In the two-section two-duct pilot precipitator with a precipitation area of 60 m/sup 2/ the plate spacing was increased up to 1,000 mm. As gas velocities values between 0.5 and 2.0 m/s were selected. The precipitator was tested with the flue gases of a coal-fired power station and in the room dedustion of an iron ore sintering plant. Starting with a plate spacing of 250 mm increasing the spacing results initially in a small increase of the precipitation rate. After reaching a maximum the rate decreases and finally with passing a critical spacing it goes below the initial value. Dedusting flue gases the spacing with the maximum and the critical spacing depend on the gas velocity. Cost analyses demonstrate that increasing the up to now used plate spacings may led to considerable savings. Depending ...

1983-01-01

232

Newtonian hydrodynamics of the coalescence of black holes with neutron stars IV Irrotational binaries with a soft equation of state  

CERN Document Server

We present the results of three-dimensional hydrodynamical simulations of the final stages of inspiral in a black hole-neutron star binary, when the separation is comparable to the stellar radius. We use a Newtonian Smooth Particle Hydrodynamics (SPH) code to model the evolution of the system, and take the neutron star to be a polytrope with a soft (adiabatic index G=2 and G=5/3) equation of state and the black hole to be a Newtonian point mass. The only non-Newtonian effect we include is a gravitational radiation back reaction force, computed in the quadrupole approximation for point masses. We use irrotational binaries as initial conditions for our dynamical simulations, which are begun when the system is on the verge of initiating mass transfer and followed for approximately 23 ms. For all the cases studied we find that the star is disrupted on a dynamical time-scale, and forms a massive (the disc mass is approximately ...

2001-01-01

233

New fuzzy dynamic programming approach for solving the hydrothermal scheduling problem  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new approach for solving multistage decision problems in power system operation by using a new fuzzy dynamic programming technique. To investigate its validity, the hydrothermal scheduling problem is used as an example problem. Within this problem, uncertainty elements exist such as load demand and natural hydraulic inflows to reservoirs exist which can be expressed by fuzzy numbers. Two new fuzzy decision making techniques for selecting the optimal operating states at each stage are introduced. Further, the hydrothermal scheduling solution obtained had an operating band defined by upper and lower bounds. To further enhance the information that this operating band provides, a midpoint operation technique that applies both forward and backward fuzzy DP is also introduced. This allows the system operator to consider current operating conditions to determine a suitable stage by stage operation policy within the bounds of the initial solution. By ...

1997-03-20

234

Modeling jet penetration in glass  

Energy Technology Data Exchange (ETDEWEB)

It is well known that composite armors, consisting of glass elements confined with metallic tampers, are extraordinarily effective against shaped charge attack. Early experiments showed that jets fired against glass targets appeared to be bombarded by tiny fragments that destroyed alignment and reduced residual jet penetration. This result was attributed to an elastic rebound effect in which the outward radial motion of the target around the jet periphery was supposed to be arrested by tensile hoop stresses which developed behind the divergent shock front. Glass fragments were then accelerated radially inward and these destabilized the jet. To sustain the large tensile hoop stresses required, the glass must not have been fractured by the initial shock, behind which the stress state is typically well above the Hugoniot elastic limit. Modeling the penetration of a jet into glass requires not only determining the spall strength, i.e., the tensile ...

1990-04-05

235

Measurements of the DDT Process in Laser and Exploding Bridgewire Detonators  

Science.gov (United States)

The deflagration-to-detonation transition of low density (0.88 g/cc) PETN during initiation by both an exploding bridgewire and laser driven source is being studied using both laser interferometry and streak photography. Cutback experiments using VISAR have confirmed a 1.0 mm run-distance to detonation in low density PETN powder. In a detonation system using a combination of low and high density powders, an apparent center of initiation (COI) analysis of streak data has yielded a surprisingly similar result. This data suggests that a compaction of low density powder to near theoretical maximum density (TMD) occurs before the onset of detonation, which is consistent with work done previously.^1 Additionally, data analysis shows that although function time increases significantly with decreasing firing voltage, the apparent COI changes very little. This indicates that the detonation criteria is not dependant upon the rate of ...

2005-07-01

236

Kinetic and isotherm studies of Cu(II) biosorption onto valonia tannin resin  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of Cu(II) from aqueous solutions by valonia tannin resin was investigated as a function of particle size, initial pH, contact time and initial metal ion concentration. The aim of this study was to understand the mechanisms that govern copper removal and find a suitable equilibrium isotherm and kinetic model for the copper removal in a batch reactor. The experimental isotherm data were analysed using the Langmuir, Freundlich and Temkin equations. The equilibrium data fit well in the Langmuir isotherm. The experimental data were analysed using four sorption kinetic models - the pseudo-first- and second-order equations, the Elovich and the intraparticle diffusion model equation - to determine the best fit equation for the biosorption of copper ions onto valonia tannin resin. Results show that the pseudo-second-order equation provides the best correlation for the biosorption process, whereas the Elovich equation ...

2009-03-15

237

Initiation of depleted uranium oxide and spent fuel testing for the spent fuel sabotage aerosol ratio programme  

Energy Technology Data Exchange (ETDEWEB)

We provide a detailed overview of an on-going, multinational test programme that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolised materials plus volatilised fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy/density device. The programme participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research programme. Sandia National Laboratories has the lead role for conducting this research programme; test programme support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. We provide a summary of the overall, multiphase test design and a description of all explosive containment and aerosol collection ...

2004-07-01

238

Initiation of depleted uranium oxide and spent fuel testing for the spent fuel sabotage aerosol ratio programme  

International Nuclear Information System (INIS)

We provide a detailed overview of an on-going, multinational test programme that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolised materials plus volatilised fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy/density device. The programme participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research programme. Sandia National Laboratories has the lead role for conducting this research programme; test programme support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. We provide a summary of the overall, multiphase test design and a description of all explosive containment and aerosol collection ...

239

Initiation of depleted uranium oxide and spent fuel testing for the spent fuel sabotage aerosol ratio program.  

Energy Technology Data Exchange (ETDEWEB)

The authors provide a detailed overview of an on-going, multinational test program that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolized materials plus volatilized fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy-density device. The program participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research program. Sandia National Laboratories has the lead role for conducting this research program; test program support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. The authors provide a summary of the overall, multiphase test design and a description of all explosive containment and aerosol ...

2004-08-01

240

Initiation of depleted uranium oxide and spent fuel testing for the spent fuel sabotage aerosol ratio program  

International Nuclear Information System (INIS)

The authors provide a detailed overview of an on-going, multinational test program that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolized materials plus volatilized fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy-density device. The program participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research program. Sandia National Laboratories has the lead role for conducting this research program; test program support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. The authors provide a summary of the overall, multiphase test design and a description of all explosive containment and aerosol ...

241

Independent oversight review of the Department of Energy Quality Assurance Program for suspect/counterfeit parts. Revision 1  

Energy Technology Data Exchange (ETDEWEB)

To address the potential threat that suspect/counterfeit parts could pose to DOE workers and the public, the Office of the Deputy Assistant Secretary for Oversight initiated a number of activities beginning in mid-1995. Oversight placed increased emphasis on the field`s quality assurance-suspect/counterfeit parts programs during safety management evaluations, in keeping with the Office of Environment, Safety and Health (EH) oversight responsibilities, which include oversight of the Department`s quality assurance (QA) programs. In addition, Oversight reviewed relevant policy documents and occurrence reports to determine the nature and magnitude of the problem within the Department. The results of that review, contained in an Office of Oversight report, Independent Oversight Analysis of Suspect/Counterfeit Parts Within the Department of Energy (November 1995), indicate a lack of consistency and comprehensiveness in the Department`s ...

1996-05-01

242

Identification method for gas-liquid two-phase flow regime based on singular value decomposition and least square support vector machine  

International Nuclear Information System (INIS)

Aiming at the non-stationary characteristics of differential pressure fluctuation signals of gas-liquid two-phase flow, and the slow convergence of learning and liability of dropping into local minima for BP neural networks, flow regime identification method based on Singular Value Decomposition (SVD) and Least Square Support Vector Machine (LS-SVM) is presented. First of all, the Empirical Mode Decomposition (EMD) method is used to decompose the differential pressure fluctuation signals of gas-liquid two-phase flow into a number of stationary Intrinsic Mode Functions (IMFs) components from which the initial feature vector matrix is formed. By applying the singular vale decomposition technique to the initial feature vector matrixes, the singular values are obtained. Finally, the singular values serve as the flow regime characteristic vector to be LS-SVM classifier and flow regimes are identified by the output of the classifier. The ...

2007-12-01

243

Hawaii Clean Energy Initiative Existing Building Energy Efficiency Analysis: November 17, 2009 - June 30, 2010  

Energy Technology Data Exchange (ETDEWEB)

In June 2009, the State of Hawaii enacted an Energy Efficiency Portfolio Standard (EEPS) with a target of 4,300 gigawatt hours (GWh) by 2030 (Hawaii 2009). Upon setting this goal, the Hawaii Clean Energy Initiative, Booz Allen Hamilton (BAH), and the National Renewable Energy Laboratory (NREL), working with select local stakeholders, partnered to execute the first key step toward attaining the EEPS goal: the creation of a high-resolution roadmap outlining key areas of potential electricity savings. This roadmap was divided into two core elements: savings from new construction and savings from existing buildings. BAH focused primarily on the existing building analysis, while NREL focused on new construction forecasting. This report presents the results of the Booz Allen Hamilton study on the existing building stock of Hawaii, along with conclusions on the key drivers of potential energy efficiency savings and on the steps necessary to attain ...

2010-06-01

244

Equilibrium, thermodynamic and kinetic studies for the biosorption of aqueous lead(II) ions onto the seed husk of Calophyllum inophyllum  

British Library Electronic Table of Contents (United Kingdom)

Biosorption of lead(II) ions from aqueous solution onto the seed husk of Calophyllum inophyllum was investigated in a batch system. Equilibrium, thermodynamics and kinetic studies were conducted by considering the effects of pH, initial metal ion concentration, contact time, and temperature. The results showed that the uptake of the metal ions increased with increase in initial metal ion concentration. The pH for optimum adsorption was 4 for the Pb(II) ions (q=4.86mg/g and 97.2% adsorption). Langmuir isotherm described the biosorption of Pb(II) ions onto the biomass (R^2=0.9531) better than the Freundlich model (R^2=0.7984), and the Temkin model (R^2=0.8761). Biosorption kinetics data obtained for the metal ions sorption were fitted using pseudo-first-order and pseudo-second-order. It was ...

2010-01-01

245

Effect of sulfur or hydrogen sulfide on initial stage of coal liquefaction in tetralin; Sekitan ekika shoki katei ni okeru io to ryuka suiso no hatasu yakuwari  

Energy Technology Data Exchange (ETDEWEB)

It is well known that the solubilization of coal can be accelerated by adding sulfur or hydrogen sulfide during direct liquefaction of difficult coals. From the studies of authors on the coal liquefaction under the conditions at rather low temperatures between 300 and 400{degree}C, liquefaction products with high quality can be obtained by suppressing the aromatization of naphthene rings, but it was a problem that the reaction rate is slow. For improving this point, results obtained by changing solvents have been reported. In this study, to accelerate the liquefaction reaction, Illinois No.6 coal was liquefied in tetralin at temperature range from 300 to 400{degree}C by adding a given amount of sulfur or hydrogen sulfide at the initial stage of liquefaction. The addition of sulfur or hydrogen sulfide provided an acceleration effect of liquefaction reaction at temperature range between 300 and 400{degree}C. The addition of sulfur or hydrogen ...

1996-10-28

246

Effect of a reminder video using a mobile phone on the retention of CPR and AED skills in lay responders.  

Science.gov (United States)

BACKGROUND: : Skills related to cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use by lay responders decay rapidly after training, and efforts are required to maintain competence among trainees. We examined whether repeated viewing of a reminder video on a mobile phone would be an effective means of maintaining CPR and AED skills in lay responders. METHODS: : In a single-blind case-control study, 75 male students received training in CPR and AED use. They were allocated either to the control or to the video-reminded group, who received a memory card containing a video clip about CPR and AED use for their mobile phone, which they were repeatedly encouraged to watch by SMS text message. CPR and AED skills were assessed in scenario format by examiners immediately and 3 months after initial training. RESULTS: : Three months after initial training, the video-reminded group showed more accurate ...

2011-09-26

247

Deterministic secure direct communication using GHZ states and swapping quantum entanglement  

International Nuclear Information System (INIS)

We present a deterministic secure direct communication scheme via entanglement swapping, where a set of ordered maximally entangled three-particle states (GHZ states), initially shared by three spatially separated parties, Alice, Bob and Charlie, functions as a quantum information channel. After ensuring the safety of the quantum channel, Alice and Bob apply a series of local operations on their respective particles according to the tripartite stipulation and the secret message they both want to send to Charlie. By three of Alice, Bob and Charlie's Bell measurement results, Charlie is able to infer the secret messages directly. The secret messages are faithfully transmitted from Alice and Bob to Charlie via initially shared pairs of GHZ states without revealing any information to a potential eavesdropper. Since there is no transmission of the qubits carrying the secret message between any two of them in the public channel, ...

2005-06-24

248

Design for environment for the National Ignition Facility  

Energy Technology Data Exchange (ETDEWEB)

The National Ignition Facility (NIF) will be a U.S. Department of Energy (DOE) national center for inertial confinement fusion (ICF) and other research into the physics of high temperatures and high densities, and a vital element of the DOE`s nuclear weapons Stockpile Stewardship and Management Program. It will be used by scientists from a numerous different institutions and disciplines to support research advancements in national security, energy, basic science, and economic development. Multiple powerful laser beams will `ignite` small fusion targets, helping liberate more energy than is required to initiate the fusion reactions. This paper discusses the Design for Environment process for NIF, some of the subsequent activities resulting from the initial study, and a few of the lessons learned from this process. Subsequent activities include the development of a Pollution Prevention and Waste Minimization Plan (P2/WMin) ...

1998-05-01

249

Collisional cooling of negative-ion beams  

Energy Technology Data Exchange (ETDEWEB)

Studies have been conducted to determine the feasibility of using collisional cooling for reducing emittances and energy spreads in negative-ion beams to levels commensurate with effective isobaric purification with conventional high-resolution electromagnetic isobar separators as required for use at the Holifield Radioactive Ion Beam Facility (HRIBF). We have designed a gas-filled radio frequency quadrupole ion cooler equipped with provisions for retarding energetic negative-ion beams to energies below thresholds for electron detachment at injection and for re-acceleration to initial energies after the cooling process. The device has been used to cool several ion beams with initial energy spreads, {delta}E>10 eV to final energy spreads, {delta}E{approx}2 eV FWHM, including O{sup -} and F{sup -}. Overall transmission efficiencies of {approx}14% for F{sup -} beams have been obtained. Experimental results show that ...

2002-01-01

250

Carbon steel corrosion rates and mechanisms in aqueous nickel chloride at 300C  

International Nuclear Information System (INIS)

Rapid corrosion of PWR steam generator carbon steel support structures and consequential denting of steam generator tubes led to considerable investigation of the mechanism of corrosion and for palliatives. The basic mechanism is now fairly well understood. Chloride present in the boiler feedwater from condenser leakage is concentrated in the support plate crevice as a result of the superheat present. This leads to the formation of a low pH acid ferrous chloride environment either through the hydrolysis of a weak base chloride such as MgCl_2 or the combined action of a neutral chloride with an oxidizing agent. Rapid attack of the carbon steel ensues with the Fe_3O_4 corrosion product forming at the metal/oxide interface. This oxide has a volume approximately twice that of the steel consumed and thus eventually fills the crevice between the tube and the support plate. Oxide growth continues leading to compression of the Alloy 600 primary tube and to distortion and ...

1985-03-01

251

Burnup determination of spent nuclear fuel in the pool  

Energy Technology Data Exchange (ETDEWEB)

A algorithm was developed to determine the characteristic parameters of PWR spent fuel, such as burnup, cooling time and initial enrichment of {sup 235}U by use of gamma-ray activity ratios of {sup 134}Cs/{sup 137}Cs, {sup 154}Eu/{sup 137}Cs and {sup 106}Ru/{sup 137}Cs from the high resolution gamma-ray spectroscopy and ORIGEN-S calculations. For the verification of the method developed, gamma-ray measurements of Kori-1 and Kori-2 nuclear fuel rods were carried out using HPGe gamma ray scanning system. As a results, it is revealed that the measured values are in a good agreement with the operator declared values within the about {+-} 5% errors. Besides, the under-water burnup measuring device has been designed to measure the gamma-ray from the PWR spent fuel assembly. This device will be set up in the pool of Post-Irradiation Examination Facility(PIEF), and used in determination of the average burnup, cooling time and ...

1998-06-01

252

Basic studies on design supporting system of offshore structures; Kaiyo kozobutsu wo taisho toshita sekkei shien system ni kansuru kisoteki kenkyu  

Energy Technology Data Exchange (ETDEWEB)

Authors already reported the integrated system so called SODAS (System Of Design and Assembling for Shipbuilding) which was based on product model concept. And products in shipbuilding industry today are not limited to ship structures alone. Therefore, it is desirable that a more global product model which can describe another products such as offshore structures should be considered. In this paper, a product model of offshore structures is discussed. Compared with the case of ship structures, the distinctive feature in the design stage of offshore structures lies in the initial design stage. Thus in this paper, some of the new model in initial design stage are introduced. Some of them are `Function Element Model` which expresses functional concept by designers. In the other design stage, product information such as `Room` and `Part` which were already introduced in SODAS are used effectively for a product model of offshore structures. By the ...

1995-12-31

253

Assessment of RELAP5/MOD3/CANDU"+ to Wolsung-1 D_2O leakage event  

International Nuclear Information System (INIS)

In order to evaluate the integrated performance of RELAP5/MOD3/CANDU"+ for CANDU operational transient analysis, we assesed the code to the D_2O leakage event occurred at Wolsung-I, 600 MW(e) CANDU reactor, on Oct. 20, '94. D_2O leakage event was initiated by stuck opening of liquid relief valve No.4 in primary coolant pressure and level control system. Assessment calculation was performed for the plant transients up to 1000 seconds after the initiating event. Calculation results are compared with those measured in primary heat transport system, pressure and inventory control system and boiler secondary system. Comparison with the plant trip log shows that the RELAP5/CANDU"+ is able to simulate the plant transients properly, from which we can conclude that the RELAP5/CANDU"+ is validated for application to CANDU operational transient analysis. CANDU specific models used in the assessment are fuel bundle heat transfer model, ...

2001-10-01

254

Reaction of solid sorbents with hydrogen chloride gas at high temperature in a fixed-bed reactor  

Energy Technology Data Exchange (ETDEWEB)

The gas-solid reaction and breakthrough curves in the fixed-bed reactor are of great importance, and being influenced by a number of factors makes the prediction of these factors a difficult problem. In this study, the reaction rate between solid sorbents and hydrogen chloride gas at high temperature was first investigated. On the basis of a fixed-bed reactor, the experimental results were analyzed by the shrinking core model of diffusion and surface chemical reaction control. The results showed that reaction rates of two sorbents with hydrogen chloride gas were controlled by the combination of the surface chemical reaction and diffusion of product layers, and the reaction rates nearly keep constant within 15 h of the initial reaction period and then decrease gradually. The results of the breakthrough curves show that solid sorbents in the fixed-bed reactor are capable of reducing the HCl level to ...

2005-12-01

255

Blunt renal trauma in children: healing of renal injuries and recommendations for imaging follow-up  

International Nuclear Information System (INIS)

Initial CT grading of renal injury was correlated with the frequency of complications and the time course of healing in 35 children. All renal contusions (grade 1, 8) and small parenchymal lacerations (grade 2, 8) healed without complications. All lacerations extending to the collecting system (grade 3, 9) resulted in mild to severe loss of renal function with progressive healing over 4 months. One of four segmental infarcts (grade 4 A), and five of six vascular pedicle injuries (grade 4 B) resulted in severe loss of renal function. Complications, including urinoma (2), sepsis (1), hydronephrosis (1), and persistent hypertension (2), were limited to grade 3 and 4 injuries. Our results suggest that mild renal injuries do not require follow-up imaging. Major renal lacerations and vascular pedicle injuries, however, often result in loss of renal function and should be followed up ...

256

Experiments in High-Frequency Imaging of the 2004 M6.0 Parkfield Earthquake  

Science.gov (United States)

We attempt to image the rupture propagation of the 2004 M6.0 Parkfield earthquake by analyzing records from the USGS Parkfield seismic array (UPSAR) and other strong-motion stations. The UPSAR array consists of 12 stations distributed over about one square kilometer at a distance of 10~km from the San Andreas fault near Parkfield, California. We employ a method that uses reverse time migration to stack the seismograms at back-projected locations along the fault. We use waveform cross-correlation to align the initial P-wave arrivals and correct for small static time shifts in the records. This forces a coherent image at the hypocenter at the quake origin time. Initial results at later time steps show some evidence of the expected rupture propagation to the north. However, the resolution of the back-projection is limited by the small aperture of the UPSAR array. Records from other strong-motion stations can improve the ...

2006-12-01

257

Toward a theory of the initiation of cancer by ionizing radiation: the twin doublet pair model  

Science.gov (United States)

Models are proposed which explain the mechanism of action on a molecular level for the initiation of cancer by electrons or alpha particles. (ACR)

1980-01-01

258

Barriers to Initiating Depression Treatment in Primary Care Practice  

UK PubMed Central (United Kingdom)

OBJECTIVE AND DESIGNThis study used qualitative and quantitative methods to examine the reasons primary care physicians and nurses offered for their inability to initiate guideline-concordant...Full Text Available

2002-02-01

259

Utilization of fermentation waste (Corynebacterium glutamicum) for biosorption of Reactive Black 5 from aqueous solution  

Energy Technology Data Exchange (ETDEWEB)

A fermentation waste, Corynebacterium glutamicum, was successfully employed as a biosorbent for Reactive Black 5 (RB5) from aqueous solution. This paper initially studied the effect of pretreatment on the biosorption capacity of C. glutamicum toward RB5, using several chemical agents, such as HCl, H{sub 2}SO{sub 4}, HNO{sub 3}, NaOH, Na{sub 2}CO{sub 3}, CaCl{sub 2} and NaCl. Among these reagents, 0.1 M HNO{sub 3} gave the maximum enhancement of the RB5 uptake, exhibiting 195 mg/g at pH 1 with an initial RB5 concentration of 500 mg/l. The solution pH and temperature were found to affect the biosorption capacity, and the biosorption isotherms derived at different pHs and temperatures revealed that a low pH (pH 1) and high temperature (35 deg. C) favored biosorption. The biosorption isotherm was well represented using three-parameter models (Redlich-Peterson and Sips) compared to two-parameter models (Langmuir and Freundlich models). As a ...

2007-03-06

260

The thematic plant life assessment network (PLAN)  

Energy Technology Data Exchange (ETDEWEB)

The Plant Life Assessment Network (PLAN) is a Brite Euram Type II Thematic Network, initiated by the European Commission to facilitate structured co-operation between all cost shared action projects already funded by the Commission which fall under this common technical theme. The projects involved address a multiplicity of problems associated with plant life assessment and are drawn from Brite-Euram, Standards, Measurement and Testing, Nuclear Fission Safety and Esprit EC programmes. The main aim of the Network is to initiate, maintain and monitor a fruitful co-operation process between completed, ongoing and future EC R and D projects, thereby promoting improved cross fertilization and enhanced industrial exploitation of R and D results. As the project is in its infancy, this presentation covers the background to the initiative in some detail. In particular two key aspects are highlighted, namely, the ...

1998-12-31

261

RAILPLUG IGNITION SYSTEM FOR ENHANCED ENGINE PERFORMANCE AND REDUCED MAINTENANCE  

Energy Technology Data Exchange (ETDEWEB)

During the first 18 months of this project, four experimental subtasks were to have begun but only one of these was to have been completed. Additionally, five modeling subtasks were scheduled to begin, four of which were to have been completed. We are on schedule for all but one of these subtasks. All four experimental tasks are progressing on schedule. Initial durability tests were completed. The conclusions drawn from this first round of durability tests are being used to design the next set of tests. Initial baseline engine data were acquired and showed that the engine selected for this task behaves as hoped. However, the dyno controller is inadequate. The engine will be moved to another dyno during the near future. The modeling tasks are also progressing well. A model for the dynamic response of the ignition circuit was developed and validated. Two technical papers resulting from this model were submitted for ...

2003-09-19

262

Prognostic factors in the treatment of Ewing's sarcoma  

International Nuclear Information System (INIS)

From 1981 up to February 1985, a total of 93 protocol patients entered the study CESS 81. The protocol recommended an initial 18-week period of polychemotherapy (VACA) followed by local therapy and two additional cycles of chemotherapy. Local therapy consisted either of radical surgery or of incomplete resection plus postoperative irradiation with 36 Gy or of radiotherapy alone (46 and 60 Gy). Centrally located lesions were always irradiated with 60 Gy. This article summarizes the data after 5 years. Data of 93 patients were analysed in October 1986 after a median follow-up of 37 months. The projected 5-year survival is 50%. The relapse rate was 42%, distant relapses occurred in 19%, local (plus distant) relapses in 23%. Most of the relapses occurred during the first 3 years of observation. Failure rate was high in patients undergoing irradiation alone (44%). Initial tumour mass (> 100 ml) and histopathologic response to ...

263

Preparation and biodistribution of yttrium-90 lipiodol in rats following hepatic arterial injection  

Energy Technology Data Exchange (ETDEWEB)

We labelled Lipiodol with yttrium-90 and analysed the biodistribution in rats after intrahepatic arterial injection. An RP-18 column was used to separate {sup 90}Y from strontium-90. {sup 90}Y was retained on the column, which had been pretreated with yttrium-selective extraction reagent, di(2-ethylhexyl) phosphate, while {sup 90}Sr was washed out. A hexadentate nitrogen-donor chelating ligand N,N,N`,N`-tetrakis(2-benzymidazolylmethyl)-1,2-ethanediamine (EDTB) was synthesized by condensation of 1,2-benzenediamine and ethylene diamine tetra-acetic acid (EDTA). Lipiodol was covalently conjugated with EDTB. The final product was obtained by eluting the retained {sup 90}Y from the RP-18 column with EDTB-Lipiodol. Sixteen male rats (Sprague-Dawley) were sacrificed at 1 h, 24 h, 48 h and 72 h (four rats at each time) after injection of approximately 0.1 mCi {sup 90}Y-Lipiodol via the hepatic artery. Samples of liver, spleen, muscle, lung, kidney, bone, whole blood and testis were obtained ...

1995-03-01

264

Outcome of moderately dosed radiosurgery for limited brain metastases. Report of a single-center experience  

International Nuclear Information System (INIS)

Purpose: Efficacy and safety of the own single-center experience with moderately dosed radiosurgery (SRS) for limited (one to four) brain metastases were analyzed and correlated with patient- and treatment-related variables. Patients and Methods: Between 05/1998 and 10/2006, 93 patients received SRS for a total of 142 brain metastases. The median number of brain metastases treated per patient was one (range, one to four). 46 patients (49%) received initial SRS alone, 13 patients (14%) SRS with up-front whole-brain radiotherapy (WBRT), and 34 patients (37%) SRS for recurrent metastases after WBRT. Median dose was 16 Gy (range, 10-20 Gy). Results: Median overall survival (OS) was 7.5 months. The actuarial 6- and 12-month data for OS were 60% and 35%, for local brain control (LBC) 87% and 79%, and for distant brain control (DBC) 48% and 37%, respectively. Only ten of 46 patients (22%) with initial SRS alone ultimately received ...

2010-02-01

265

Initiation process of type 1 pitting corrosion on copper water-tubes; Reisui yo dokan ni okeru 1 gata koshoku no hassei  

Energy Technology Data Exchange (ETDEWEB)

Copper tubes have been widely used for water supply and heat exchangers. In such systems copper tubes often suffer from type 1 pitting-corrosion. A mechanism, of the type I pitting-corrosion on copper tubing has been presented, but a initiation mechanism of the pitting corrosion is still unknown. In this paper we aimed to clarify the initiation mechanism of the pitting corrosion. Copper-tube specimens were immersed in a circulating solution. The solution had been used for heat exchangers at a Japanese factory where the water leakage occurred by the pitting corrosion on copper tubes. The solution contained tiny precipitates resulted from corrosion of galvanized steel pipe. During the immersion test changes in the surface state of a copper tube was analyzed by in situ RAMAN (in situ Raman Spectroscopy), SEM (Scanning Electron Microscope), EPMA (Electron Probe Microanalysis), AES (Auger Electron Spectroscopy) and XPS (X-ray ...

1999-07-15

266

Impact of different auxins of the regeneration of chrysanthemum (dendranthema morifolium) through in vitro shoot tip culture  

International Nuclear Information System (INIS)

Shoot tip explants of chrysanthemum were checked for their in vitro regeneration capability when they were inoculated on MS media supplemented with three different auxins viz., IAA, NAA and IBA with their different concentrations (Control, 0.1, 0.3 and 0.5 mg/l IAA; Control, 0.5, 1.0 and 1.5 mg/l NAA; Control, 0.3, 0.7 and 1.0 mg/l IBA). The lowest concentration of IAA (0.1 mg/l) showed the best response in all the parameters, as it gave the highest (86.6%) shoot initiation, maximum (3.9) shoots per explant, shoot length (4.3 cm), 10.0 leaves per shoot and 4.8 nodes per shoot. Comparing different concentrations of NAA, it was evident from the results that the lowest concentration of 0.5 mg/l NAA showed its superiority over the other concentrations, as it produced as high as 80.0% shoot initiation, maximum 3.2 shoots per explant, shoot length (4.0 cm), 9.5 and 4.5 leaves nodes per shoots. Whereas, amongst the various IBA ...

267

Evaluation of a positive ventilation delivery system (PVDS) in administering technegas to the noncompliant patient  

International Nuclear Information System (INIS)

Full text: Certain groups of patients have been excluded from ventilation lung scanning due to their inability to comply with instruction. Tetley Manufacturing have recently developed a Positive Ventilation Delivery System (PVDS) which assists in delivering Technegas to patients who are unable to cooperate fully. The aim of this study is to evaluate the PVDS in the clinical setting. Fifteen frail aged and psychogeriatric patients (n=l 5), mean age 78 years (range 60-93), were ventilated with Technegas using the PVDS. The decision to ventilate the patient with the PVDS was based on an initial assessment of the patients ability to comply with instructions, or failure of the conventional ventilation method, to produce an adequate count rate. Technegas was prepared in the usual manner and then delivered to the patients lungs by squeezing a black anesthetic bag synchronously with the patients breathing, until a count rate of approximately 1000 counts/second was ...

1998-06-01

268

Comparison of Ceramic, Metal and Polymer Crevice Formers on the Crevice Corrosopn Behavior of Ni-CR-Mo Alloy C22  

Energy Technology Data Exchange (ETDEWEB)

A necessary condition for crevice corrosion is that a crevice former create a sufficiently tight, restricted geometry on the metal surface to support the development of critical crevice chemistry. Crevice corrosion is affected by the crevice geometry (tightness) and the properties of the crevice former. The objective of this study is to determine the effect of the crevice former material on the evolution of localized corrosion-damage. A standard crevice corrosion test method is modified by (a) the use of ceramic, metal or polymer materials as the crevice former and (b) the variation of size and shape of the crevice. This study focuses on the post initiation stage of crevice corrosion and addresses factors that may limit the initiation of localized corrosion and also slow or stop the continued propagation of corrosion. Controlled crevice corrosion tests are performed under aggressive, accelerated conditions on Ni-Cr-Mo alloy C-22 and other ...

2006-05-08

269

Biosorption of Cd(II), Ni(II) and Pb(II) from aqueous solution by dried biomass of aspergillus niger: application of response surface methodology to the optimization of process parameters  

Energy Technology Data Exchange (ETDEWEB)

In this study, the biosorption of Cd(II), Ni(II) and Pb(II) on Aspergillus niger in a batch system was investigated, and optimal condition determined by means of central composite design (CCD) under response surface methodology (RSM). Biomass inactivated by heat and pretreated by alkali solution was used in the determination of optimal conditions. The effect of initial solution pH, biomass dose and initial ion concentration on the removal efficiency of metal ions by A. niger was optimized using a design of experiment (DOE) method. Experimental results indicated that the optimal conditions for biosorption were 5.22 g/L, 89.93 mg/L and 6.01 for biomass dose, initial ion concentration and solution pH, respectively. Enhancement of metal biosorption capacity of the dried biomass by pretreatment with sodium hydroxide was observed. Maximal removal efficiencies for Cd(II), Ni(III) and Pb(II) ions of 98, 80 and ...

2009-10-15

270

Application of the porous media model for the LWR process components  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: A porous media solution PORFLO has been developed for the 3-dimensional two-phase flow by describing the process facility in Cartesian or cylindrical coordinates. The local porosity fraction is applied for distinguishing the fluid filled volumes from the solid structures. The solid structure contribute the two-phase flow through the wall friction, flow area and heat transfer. Optionally the solid structure may contain primary liquid of steam generators, steam in the higher temperature and pressure to be condensed or electrical heating power. By using these optional boundary conditions three different process facilities have been analysed. The thermohydraulic solution based on 5-equation approach, where the conservation equations are solved for the liquid and gas (vapour) mass, mixture momentum (giving the velocity only for the mixture), liquid and gas energy, is described shortly. In addition to that the principles modelling optional boundary ...

2005-07-01

271

Upgrading Athabasca tar sand using toe-to-heel air injection  

Energy Technology Data Exchange (ETDEWEB)

A new air injection process called toe-to-heel air injection (THAI) has been developed to achieve very stable combustion performance in heavy oil wells by controlling gas override. In the THAI process, injected air migrates preferentially to the combustion front into a horizontal producer well by the oxygen diffusional gradient created under steady state conditions. This is possible because of the balance between the stoichiometric oxygen flux needed to burn the fuel (coke) laid down ahead of the combustion front and the removal of downstream combustion gases and mobilised fluids. This study involved a numerical simulation of the THAI process to increase the understanding of the processes involving fluid flow, heat transfer and chemical reactions taking place during in situ combustion. Two tests were conducted involving one dry and one wet combustion using heavy Wolf Lake Oil. The objective was to determine if the behaviour of the oil could be predicted. A corresponding ...

2000-11-01

272

Steam Generator Group Project: Annual report, 1985  

Energy Technology Data Exchange (ETDEWEB)

This report is a summary of the Steam Generator Group Project progress for 1985. Statistical analyses are presented of data from nondestructive examination (NDE) round robin tests that were performed on the Surry generator in 1984. In the first round robin, teams acquired and analyzed their own data on a selected 10% subset of tubes. In the second round robin, analysts from each participating team analyzed identical sets of data which were provided to them by the Project. Results from several examinations utilizing advanced/alternate NDE technologies including alternate eddy current probes and techniques, ultrasonics, and profilometry are also reported. Criteria are listed for selecting tube specimens that will be removed from the generator. A sampling plan based on these criteria is detailed graphically in the report. The initial steps that have been taken to carry out the plan are described; tooling fabricated for the sample removals is ...

1987-04-01

273

Steam Generator Group Project: Annual report, 1985  

International Nuclear Information System (INIS)

This report is a summary of the Steam Generator Group Project progress for 1985. Statistical analyses are presented of data from nondestructive examination (NDE) round robin tests that were performed on the Surry generator in 1984. In the first round robin, teams acquired and analyzed their own data on a selected 10% subset of tubes. In the second round robin, analysts from each participating team analyzed identical sets of data which were provided to them by the Project. Results from several examinations utilizing advanced/alternate NDE technologies including alternate eddy current probes and techniques, ultrasonics, and profilometry are also reported. Criteria are listed for selecting tube specimens that will be removed from the generator. A sampling plan based on these criteria is detailed graphically in the report. The initial steps that have been taken to carry out the plan are described; tooling fabricated for the sample removals is ...

274

Science and common sense in Port Valdez, Alaska  

Energy Technology Data Exchange (ETDEWEB)

Valdez, Alaska achieved worldwide attention with the Exxon Valdez oil spill. This exacerbated an already polarized situation (industry, government, citizens, environmental groups) regarding the Valdez Terminal of the Trans Alaska Pipeline System. Other than spills, the major focus of environmental concern was and remains the Terminal`s Ballast Water Treatment Plant (BWTP) which discharges into Port Valdez. The previous NPDES wastewater discharge permits for this facility have been contentious for almost the entire period of pipeline operation. The draft NPDES permit is scheduled to be proposed for reissuance this year. However, a significant change has been initiated which so far is resulting in cooperation rather than confrontation between the various primary stakeholders. This presentation will explain how this change was initiated, how it is being maintained, and how what is happening could be a model for progress ...

1995-12-31

275

General-purpose heat source development: Extended series test program SRB fragment/fuselage tests  

Energy Technology Data Exchange (ETDEWEB)

General-Purpose Heat Source radioisotope thermoelectric generators (GPHS-RTGs) will provide electrical power for the NASA Galileo and European Space Agency (ESA) Ulysses missions. Each GPHS-RTG comprises two major components: GPHS modules, which provide thermal energy, and a thermoelectric converter, which converts the thermal energy into electrical power. Each of the 18 GPHS modules in a GPHS-RTG contains four /sup 238/PuO/sub 2/-fueled capsules. LANL conducted a series of safety verification tests on the GPHS-RTG before the scheduled May 1986 launch of the Galileo spacecraft to assess the ability of the GPHS modules to contain plutonia in potential accident environments. As a result of the Challenger 51-L accident in January 1986, NASA postponed the launch of Galileo; the spacecraft launch vehicle was reconfigured and the spacecraft trajectory modified. These actions prompted NASA to reevaluate potential mission accidents and the extended series safety test ...

1989-06-01

276

Flow-system analysis of exfoliated pulmonary cells: results of initial characterization studies in hamsters  

Science.gov (United States)

This paper summarizes results of preliminary experiments to develop cytological and biochemical indicators for estimating damage to respiratory cells in test animals exposed by inhalation to toxic agents associated with nonnuclear energy production, the specific goal being the application of advanced multiparameter flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. Normal Syrian hamster lung cell samples composed of histiocytes, leukocytes, macrophages, ciliated columnar cells, and epithelial cells were stained with fluorescent dyes specific for different biochemical parameters and were analyzed in liquid suspension as they flowed through a chamber intersecting a laser beam of exciting light. Multiple sensors measured the total or two-color fluorescence and light scatter on a cell-by-cell basis. Cellular parameters proportional to optical measurements (i.e., cell size, DNA content, total protein, nonspecific esterase ...

1976-01-01

277

Diffusion and adsorption of methane confined in nanoporous carbon aerogel: a combined quasi-elastic and small-angle neutron scattering study  

Energy Technology Data Exchange (ETDEWEB)

The diffusion of methane confined in nano-porous carbon aerogel with the average pore size 48 {angstrom} and porosity 60% was investigated as a function of pressure at T = 298 K using quasi-elastic neutron scattering (QENS). The diffusivity of methane shows a clear effect of confinement: it is about two orders of magnitude lower than in bulk at the same thermodynamic conditions and is close to the diffusivity of liquid methane at 100 K (i.e. {approx} 90 K below the liquid-gas critical temperature T{sub C} {approx} 191 K). The diffusion coefficient (D) of methane initially increases with pressure by a factor of {approx}2.5 from 3.47 {+-} 0.41 x 10{sup -10} m{sup 2} s{sup -1} at 0.482 MPa to D = 8.55 {+-} 0.33 x 10{sup -10} m{sup 2} s{sup -1} at 2.75 MPa and starts to decrease at higher pressures. An explanation of the observed non-monotonic behavior of the diffusivity in the confined fluid is based on the results of small-angle neutron ...

2010-04-01

278

A study on the regulatory approach of KNGR multiple failure events  

Energy Technology Data Exchange (ETDEWEB)

This project is to provide the regulatory direction of containment bypass during multiple steam generator tube failure issue for the Korean Next Generation Reactors, which is a part of major technical issues resulted from the safety regulation R and D on the KNGR. The outstanding results are as follows : the Multiple Steam Generator Tube Repture(MSGTR) event has never been occurred in the history of commercial nuclear reactor operation but single Steam Generator Tube Rupture(SGTR) event is reported to occur every two years. A probabilistic safety analysis study on MSGTR event, however, show its probability of occurrence is to be the same order as the design basis accidents such as LACA. In this regard, the ability of NPPs to cope with MSGTR event is required. Some requirements on initial and boundary conditions are suggested to be used in the analyses of NPPs during MSGTR events. The items that should be considered in ...

2001-01-15

279

[Reactive collisions of high-temperature systems]. [Technical progress report 1990  

Energy Technology Data Exchange (ETDEWEB)

The object of this research is to study reactivity at superthermal collision energies using a fast neutral beam that is generated by photodetachment. Systems scheduled for initial study include basic oxygen-hydrogen reactions. Unfortunately, we can not yet report realization of this goal, but during this funding period we have made advances that are anticipated to lead to successful measurements during the next year. The parameters described below refer to the model system O + H{sub 2} {yields} OH + H. The basic design involves the collision of fast neutrals, created by photodetachment of the corresponding negative molecular ion, with a stable reactant gas in a collision cell. Products are detected by ionization and mass analysis. We are equipped to study rotational effects on reactivity by comparing results for rotational levels J = 0 and 1 of H{sub 2}. Highlights during the funding period are given in this report.

1990-12-31

280

Wetlands mapping with spot multispectral scanner data  

Energy Technology Data Exchange (ETDEWEB)

Government facilities such as the US Department of Energy's Savannah River Plant (SRP) near Aiken, South Carolina, often use remote sensing data to assist in environmental management. Airborne multispectral scanner (MSS) data have been acquired at SRP since 1981. Various types of remote sensing data have been used to map and characterize wetlands. Regional Landsat MSS and TM satellite data have been used for wetlands mapping by various government agencies and private organizations. Furthermore, SPOT MSS data are becoming available and provide opportunities for increased spacial resolution and temporal coverage for wetlands mapping. This paper summarizes the initial results from using five dates of SPOT MSS data from April through October, 1987, as a means to monitor seasonal wetland changes in freshwater wetlands of the SRP. 11 refs., 4 figs.

1989-01-01

281

Use of shell model calculations in R-matrix studies of neutron-induced reactions  

Energy Technology Data Exchange (ETDEWEB)

R-matrix analyses of neutron-induced reactions for many of the lightest p-shell nuclei are difficult due to a lack of distinct resonance structure in the reaction cross sections. Initial values for the required R-matrix parameters, E,sub(lambda) and ..gamma..sub(lambdac) for states in the compound system, can be obtained from shell model calculations. In the present work, the results of recent shell model calculations for the lithium isotopes have been used in R-matrix analyses of /sup 6/Li+n and /sup 7/Li+n reactions for E sub(n) < 8 MeV. Consequences of the shell model predictions for the level structure of /sup 7/Li and /sup 8/Li on the /sup 6/Li+n and /sup 7/Li+n reaction mechanisms and cross sections are discussed.

1986-01-01

282

Traditional Medicine Collection Tracking System (TM-CTS): A database for ethnobotanically driven drug-discovery programs  

British Library Electronic Table of Contents (United Kingdom)

Ethnopharmacological relevance: Ethnobotanically driven drug-discovery programs include data related to many aspects of the preparation of botanical medicines, from initial plant collection to chemical extraction and fractionation. The Traditional Medicine Collection Tracking System (TM-CTS) was created to organize and store data of this type for an international collaborative project involving the systematic evaluation of commonly used Traditional Chinese Medicinal plants. Materials and methods: The system was developed using domain-driven design techniques, and is implemented using Java, Hibernate, PostgreSQL, Business Intelligence and Reporting Tools (BIRT), and Apache Tomcat. Results: The TM-CTS relational database schema contains over 70 data types, comprising over 500 data fields. Th...

2011-01-01

283

Thyroid cancer stem cells  

British Library Electronic Table of Contents (United Kingdom)

Thyroid cancer is the most frequently diagnosed endocrine cancer and causes more deaths than all other endocrine cancers combined. Research findings support the concept that a subpopulation of thyroid cancer cells displays properties characteristic of stem cells. These putative cancer-forming entities drive tumorigenesis as a result of their dual ability to undergo self-renewal and to differentiate into various types of cancer cells; they also mediate metastasis and are resistant to the effects of chemotherapy and radiation therapy. This Review discusses the cellular origin of thyroid cancer and the properties of the thyroid cancer stem cell niche. The article critically evaluates the methods used to identify molecular markers expressed by thyroid-cancer-initiating cells and outlines prosp...

2011-01-01

284

Throwaway versus regeneration of condensate resin: Radwaste impact  

International Nuclear Information System (INIS)

The evaluation methodology utilized in deciding to change over Oyster Creek plant operation from chemical regeneration of condensate demineralizer resin beds to throwaway of this spent resin is presented. Both the economic and operational aspects considered are discussed. The evaluation shows that potential savings in the $1.1M range are feasible over a 5 year cycle. Cost sensitivity analysis results define the throwaway versus regeneration breakeven point to be 47 condensate demineralization beds per 5 year cycle. The evaluation also discusses the trade off between resin and evaporator concentrates burial volumes. Analyses are given which show that the burial volume cost equivalency of resin to solidified concentrates is 150 ft./sup 3/ of resin equals 400 ft./sup 3/ of concentrates. Based on one year of power operation in the throwaway mode, the savings and operational value anticipated in the initial study are being realized.

285

The use of peritoneal venous shunting for intractable neonatal ascites: a short case series  

British Library Electronic Table of Contents (United Kingdom)

Introduction: Intractable ascites in neonates has a varied etiology; and often, the cause is idiopathic. The management usually consists of observation, diuretics, paracentesis, albumin replacements, and self correction. However, in some cases, the above treatment remains unsuccessful. Results: We present 2 cases of intractable ascites causing metabolic abnormalities, severe protein and immunoglobulin loss, and respiratory compromise. Although the use of peritoneovenous shunts for intractable ascites has been reported previously, our cases differ in both technique and patient size. Our first patient is an ex-28-week premature, 1.4-kg infant with intractable ascites for which a peritoneal drain was initially placed. After 3 weeks and putting out nearly 300 mL of ascitic fluid daily, we plac...

2011-01-01

286

The role of natural circulation in the FFTF [Fast Flux Test Facility] passive safety tests  

International Nuclear Information System (INIS)

A series of tests were completed at the Fast Flux Test Facility to demonstrate the passive safety characteristics of liquid metal reactors with natural circulation flow. The first test consisted of transition from forced to natural circulation flow at an initial decay power of 0.3%. The second test represented an unprotected loss-of-flow transient to natural circulation from 50% power with the control rods prevented from scramming into the core. The third test was a steady-state, natural circulation condition with core fission powers up ato about 2.3%. Core sodium data and results of single and multi-channel computer models confirmed the reliability and effectiveness of natural circulation flow for liquid metal reactor safety.

1987-12-13

287

The influence of normal human ageing on automatic movements  

British Library Electronic Table of Contents (United Kingdom)

There is evidence that aged normal subjects have more difficulty in achieving automaticity than young subjects. The underlying central neural mechanism for this phenomenon is unclear. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the effect of normal ageing on automaticity. Aged healthy subjects were asked to practice self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Although it took more time, most aged subjects eventually performed the tasks automatically at the same level as the young subjects. Functional MRI results showed that, for bot...

2005-01-01

288

The influence of heating rate on the response and trapping parameters of {alpha}-Al{sub 2}O{sub 3}:C  

Energy Technology Data Exchange (ETDEWEB)

The effects of the heating rate from 0.6 up to 50{sup o}C.s{sup -1} on the thermoluminescence of {alpha}-Al{sub 2}O{sub 3}:C are very intensive. The material rapidly loses its high sensitivity as the heating rate increases. The peak shape characteristics, peak maximum and full width at half maximum agree only qualitatively with those theoretically predicted. The trapping parameters calculated by the curve fitting method, the peak shape method, the variable heating rate method and the initial rise method, were found to decrease as the heating rate increases. The validity of the results are discussed in the framework of the kinetic models. (author).

1994-12-31

289

The influence of heating rate on the response and trapping parameters of #alpha#-Al_2O_3:C  

International Nuclear Information System (INIS)

The effects of the heating rate from 0.6 up to 50"oC.s"-"1 on the thermoluminescence of #alpha#-Al_2O_3:C are very intensive. The material rapidly loses its high sensitivity as the heating rate increases. The peak shape characteristics, peak maximum and full width at half maximum agree only qualitatively with those theoretically predicted. The trapping parameters calculated by the curve fitting method, the peak shape method, the variable heating rate method and the initial rise method, were found to decrease as the heating rate increases. The validity of the results are discussed in the framework of the kinetic models. (author).

290

The effect of neutrals on the performance of plasma opening switches  

Energy Technology Data Exchange (ETDEWEB)

The authors address the question of the limitations on voltage and current transfer to loads in magnetic storage systems utilizing microsecond conduction time plasma opening switches. They propose that the limitation of performance results from neutral atoms that are not entrained into the ionized material that is driven by the magnetic field of the rising generator current. Evidence in support of this proposition is gathered from experiments performed on the Ace-4 and Hawk generators. They set forth a theory to describe the effect of neutrals on the electrical performance of plasma opening switches. The neutral gas is assumed to be present in the region between the moving plasma mass and the generator, primarily in the region in which the plasma is injected initially. The essential elements of the theory are a weak photoionization source to seed the gas with a low concentration of electrons, and joule heating accompanied by further ionization ...

1996-12-31

291

The effect of biomass pyrolysis gas reburning on N2O emission in a coal-fired fluidized bed boiler  

British Library Electronic Table of Contents (United Kingdom)

The fossil fuel consumption and pollutant emissions in a coal fired fluidized bed boiler could be reduced by biomass pyrolysis gas reburning. The influence of three kinds of biomass pyrolysis gases on the emission of N2O in a laboratory scale fluidized bed was investigated using the mechanism of GRI3.0 in this paper. The results showed that: the effect of sawdust pyrolysis gas reburning on N2O was more significant than that of rice husk and orange peel under the same conditions; the increase of initial oxygen content from 1% to 8% in flue gas would restrain the decomposition of N2O; the N2O decomposition was enhanced by increasing reaction temperature from 1073.15 K to 1323.15 K, and the decomposition rate may reach 99% at 1223.15 K.

2011-01-01

292

The EKC for SO2: Does firm size matter?  

British Library Electronic Table of Contents (United Kingdom)

The environmental Kuznets curve hypothesis (EKC) predicts an inverse U-shaped relationship between environmental pollution and per capita income. The literature with respect to the EKC is vast but far from conclusive. This paper adds firm size to the standard EKC reduced form regression and analyses whether firm size matters once income and composition are controlled for. Results suggest that large firm countries are initially associated with higher levels of environmental damage. However, as economies develop, large firm countries find it easier to adopt more stringent environmental legislation. Once environmental damage starts to decrease, the decrease is much larger in large firm countries.

2006-01-01

293

Texture transformations in thermomechanically treated steels having increased nitrogen content and alloys  

International Nuclear Information System (INIS)

In this study the results of mathematical simulation and experimental research of texture transition in stress assisted shear phase transformations are discussed. The orientation distribution function (ODF) calculation model to the any type crystalline lattice symmetry materials has been suggested. By crystalline lattice symmetry analysis this computer program determines necessary amount of the initial experimental data. The experimental verification supports this model well. The ODF calculation model after shear phase transformation with equal use of all possible variants of orientation relationship or with various degrees of variant selection worked out. In this study the experimental and calculating data of the direct and reversal shear transformations #alpha# <=> #gamma# in Fe-alloys and B2 <=> B19' in Ti-Ni alloys are discussed. The stress assisted shear phase transformation model and computer program to calculate ODF after ...

294

Technological evolution and interdependence in China's emerging biofuel industry  

British Library Electronic Table of Contents (United Kingdom)

This study uses the European Patent Office worldwide patent database and applies two-stage interactive data collection methods to reveal the evolving technological interdependence for China's emerging biofuel industry. Three findings are excerpted from our empirical results. First, due to dominant patterns of business ownership, China's biofuel technology is seen as largely based on the evolutionary strength of the foodstuff and chemical fields. Second, China's biofuel technology development has evolved in the mode of 'forward engineering', led by Chinese universities rather than initiated by the public research institutes as in the experience of other East Asian latecomers. Third, our patent map and technology trajectory analyses illustrate that China's biofuel technology tends to be appl...

2011-01-01

295

Surface oxidation of Co2+ and its dependence on ligand coordination number in silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

Coordination of CoCl2 solutions to the silica polyamine composite, WP-1, made with the branched polymer polyethylenimine (PEI) shows irreversible binding resulting from surface oxidation of the Co2+-Co3+. This is not the case for the silica polyamine composite BP-1 made with the linear polymer polyallylamine where reversible binding and no oxidation is observed. These observations suggested that oxidation of the cobalt was related to the greater coordination number available with the branched polyamine relative to the linear polyamine. A study of the kinetics of cobalt binding to WP-1 indicated initial loading of Co2+ at relatively low coordination number followed by desorption of Co2+ leading to oxidation and irreversible binding. Exclusion of oxygen from the composite-cobalt solution mix...

2010-01-01

296

Superphenix 1 steam generator fabrication  

Energy Technology Data Exchange (ETDEWEB)

The Superphenix 750-MW (thermal), once-throughtype steam generators are the result of over 10 years of intensive research and development. Detailed design and manufacture of the components lasted from 1977 to 1982. The main difficulties encountered during the construction of these prototype units concerned: demonstration of satisfactory high-temperature properties of Alloy 800 tubes; proven resistance of tube welds to thermal fatigue and of structures and shells to sodium/ water reaction effects; prevention of the tube bundle to flow-induced vibration; necessity of manual welding of shells to prevent hot cracking hazards related to the boron content of the steel; and welding of heat exchange tubes. None of these difficulties, however, invalidated initial major design choices, but provided a wealth of technical and technological experience and knowledge for the steam generators of the future. Plans for the future include revision of the ...

1985-02-01

297

Study of even-A zirconium and strontium isotopes with the (d,"6Li) reaction  

International Nuclear Information System (INIS)

All stable even-A molybdenum isotopes and sup(90,92)Zr have been investigated with the (d, "6Li) reaction at Esub(d) = 45 MeV to study proton- and neutron-pair correlations. Differential cross sections were measured for states up to Esub(x) = 3 MeV in "8"6Sr, sup(88,92,94,96)Zr and up to 6 MeV in "8"8Sr and "9"0Zr. Particular attention was paid to the comparison of #alpha#-pickup data with two-nucleon pickup data. The population of low-lying 0"+ and 5"- states for two-neutron and four-nucleon pickup reactions was calculated using simple phenomenological wave functions for the initial and final states. The results of these calculations are in satisfactory agreement with the data. (orig.).

298

Structure and properties of a metastable #beta#-alloy aged after plastic deformation  

International Nuclear Information System (INIS)

Phase and structural transformations in a multicomponent (5.05 mas.% Mo-4.95V-3.00Cr-3.05Al) metastable #beta#-titanium alloy on aging after plastic deformation are studied using methods of electron microscopy and X-ray diffraction analysis. The alloy is deformed by twinning in a #left brace#332#right brace# system, and even at initial stages the formation of a twin skeleton takes place in the structure, on further loading the deformation of the skeleton is by secondary twinning resulting in a high plasticity of the alloy. On annealing mechanical twins transform into #alpha#-phase - a ductile twin skeleton is replaced by a rigid skeleton of #alpha#-phase plates. The aging enhances the yield strength of the alloy but decreases sharply its plasticity

2004-12-01

299

Structural analysis and modifications-2 tankers for offshore FPSO and FSO service  

British Library Electronic Table of Contents (United Kingdom)

This paper addresses the unique structural requirements for successful conversion of tankers for floating production storage and offloading (FPSO) or floating storage and offloading (FSO) service. A description is given of the steps undertaken during two recent and very different conversions of a highly optimized 1980s VLCC to FPSO service, and a typical robust 1970s ULCC to FSO service. The paper describes the steps needed for ensuring the FPSO or FSO requirements are successfully met during conversion of the two tankers - each having its own history, e.g. date of build, original design, material choices, class society, voyage history and repairs. Firstly, the paper describes the procedure and results of an early initial structural assessment procedure on the basis of an American Bureau o...

2008-01-01

300

Split anterior tibial tendon transfer for varus equinus spastic foot deformity  

British Library Electronic Table of Contents (United Kingdom)

Spastic equinovarus foot deformity commonly occurs after stroke or head trauma. Management by split anterior tibial tendon transfer to the lateral border of the foot was chosen by the authors. The purpose of that work was to assess the reliability of this method to improve patient's functional autonomy and investigate the relationship between the initial clinical examination findings and the quality of the functional results. 84 feet, operated in 82 patients out of 130, of mean age 46 years, were reviewed at a mean follow-up of 65 months. Very few complications were observed. Toe deformities remain a commonly associated problem. 80 patients were able to walk barefoot, 74 reported an increase in their walking distance, and 73 could regularly wear normal shoes. There is a strong relationship...

2011-01-01

301

Space reactor fuel element testing in upgraded TREAT  

Energy Technology Data Exchange (ETDEWEB)

The testing of candidate fuel elements at prototypic operating conditions with respect to temperature, power density, hydrogen coolant flow rate, etc., a crucial component in the development and qualification of nuclear rocket engines based on the Particle Bed Reactor (PBR), NERVA-derivative, and other concepts. Such testing may be performed at existing reactors, or at new facilities. A scoping study has been performed to assess the feasibility of testing PBR based fuel elements at the TREAT reactor. initial results suggest that full-scale PBR, elements could be tested at an average energy deposition of {approximately}60--80 MW-s/L in the current TREAT reactor. If the TREAT reactor was upgraded to include fuel elements with a higher temperature limit, average energy deposition of {approximately}100 MW/L may be achievable.

1993-05-01

302

Smoothing of laser energy deposition by gas jets  

International Nuclear Information System (INIS)

Smoothing of laser beam non-uniformities using gas jets has been studied. The experiment has been performed with the PALS (Prague Asterix Laser System) laser working at 0.44 ?m with an intensity of about 1015 W/cm2. The laser beam has been split in two by a prism thus creating an artificial large-scale non-uniformity (? 90 ?m). We recorded time resolved and static images of laser-gas jet interaction with and without an Al target. Multi 1-dimensional and 2-dimensional simulations show that such interaction acts redistributing the over-intensities over larger surface. This effect has to be attributed to ionization processes with consequent laser beam refraction. Results show that Argon gas jet produces a strong refraction of the laser beam thus strongly reducing the initial two spots separation. (authors)

2009-08-01

303

Seasonal variation measurements of radon levels in caves using SSNTD method  

Energy Technology Data Exchange (ETDEWEB)

The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm{sup -3}, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves.

2008-08-15

304

Seasonal variation measurements of radon levels in caves using SSNTD method  

International Nuclear Information System (INIS)

The results of radon concentration measurements inside of the Gabriel caves of Mexico, during three consecutive two-month periods covering almost three seasons, are reported in the present work. The radio-ecological importance of this site is related to the radon and its concentration-dynamic behavior in the cave. Further interest in radiation safety motivated this initiative since routine biological field work is done, with people spending long periods of time there. CR-39 passive nuclear track detector was chosen for this survey. Radon concentration levels decrease during the rainy season and show different values depending on the ventilation and geometeorological structure. Measured values range between 956 and 4931Bqm-3, an indication that radon doses may exceed the allowed values for workers. This project is part of a larger study of indoor radon alpha emitters in Mexican caves.

2008-08-01

305

Roles and challenges of the health information management educator: a national HIM faculty survey.  

Science.gov (United States)

Health information technology initiatives created the framework for a national health information infrastructure that concomitantly fostered a need to build intellectual capacity within our current and future health information management (HIM) work force. Results from the 2008 HIM Educator Survey are discussed. Developed for voluntary electronic participation, the survey comprised a series of questions about educators' professional interests and responsibilities. Summary data from the 402 respondents are provided and highlight areas such as academic rank, teaching status, salary range, levels of interest in various issues, and use of virtual learning tools. Data from this survey provide insights into the concerns and challenges many HIM educators face in today's training institutions and suggest implications for future directions in work force training and professional development within the HIM field. PMID:19424453

2009-04-30

306

Robust curve fitting method for single binding site mass action model of radioimmunoassay  

International Nuclear Information System (INIS)

The difficulty and unstability of the parameter estimation of mass action model for radioimmunoassay are the major obstacles to its application in routine work. A unique robust curve fitting method for the mass action model was introduced. large numbers of simulated data were generated with Monte Carlo method to compare the accuracy and robustness of the robust fitting and the least squre fitting (Marquardt method) of the mass action model. The results demonstrated that the new robusst method significantly increased the accuracy and reliability of data processing with the mass action model. It also markedly reduced the influence of outliers in the fitting of RIA data, and it was always 'convergent'. This robust method could also be applied to other mathematical models which can be transformed into high degree equations and no initial estimates are needed for curve fitting.

307

Results of laboratory studies to investigate new gel-forming composites for temporary capping of beds  

Energy Technology Data Exchange (ETDEWEB)

Formulas were developed based on an aqueous solution of hydrolyzed polyacrylonitrile widely used in the oil industry. The additive used consisted of products of industrial production: synthetic resin TEG-1 with hardening agent PEPA (polyehtylene polyamine) and technical formalin. The mixtures containing about 80-85% by volume 5% hydrolyzed polyacrylonitrile, 10-15% by volume of resin TEG-1 with hardening agent PEPA and 3-5% by volume formalin satisfy the requirements made for the plugging materials. The initial mixtures are distinguished by technological efficiency of preparation and have controllable hardening periods. Physical-chemical properties are given for the gel polymers. In the set of properties, the mixtures based on hydrolyzed polyacrylonitrile, resin TEG-1 with hardening agent PEPA and formalin can be recommended as plugging materials of temporary action with complex treatment of the heterogeneous beds.

1982-01-01

308

Resonances in gravitational scenario given by deformed branes  

Science.gov (United States)

In this work we examine a five-dimensional brane-world model with brane structure driven by a real scalar field. From the deformation of a kink-like defect we find a new class of brane solutions containing internal structures which have implications for the way the background space-time is constructed and the way its curvature behaves. Initially, for spin 0 scalar field, we find a zero mode which can be localized on the deformed brane. However, this result can change by the gravitational interaction with the brane internal structure. Analyzing the massive modes of the scalar field, using two different methods, we find resonance structures similar to those found in the study of gravity localization. The main objective here is to observe the contributions of the deformation procedure to the resonances and to the well known field localization methods.

2011-08-01

309

Removal of aqueous phenol and 2-chlorophenol with purified soybean peroxidase and raw soybean hulls  

Energy Technology Data Exchange (ETDEWEB)

The removal phenol and 2-chlorophenol using soybean seed-hulls in the presence of hydrogen peroxide was demonstrated. The performance of a stirred membrane reactor containing soluble purified SEP was compared with a batch stirred reactor containing raw soybean seed-hulls. The purified enzyme reactor proved to be ineffective while good results were obtained with the crude seed-hulls for the removal of phenol and 2-chlorophenol. A single batch reactor containing raw seed-hulls was effective in removing more than 98.5% of 2-chlorophenol (initially at 10000 ppm) in less than 15 min. The performance of these rectors is comparable to existing HRP-based technology. The stability of the soybean peroxidase (SBP) enzyme was also examined in the presence of detergents (SDS, Tween 20 and Triton X-100).

1999-08-01

310

Reconnaissance radiological characterization for the White Point Nike Missile Site, San Pedro, California  

International Nuclear Information System (INIS)

This report is the result of field work performed at the former White Point Nike Missile Site, San Pedro, California. The Hazardous Waste Remedial Actions Program tasked the Oak Ridge National Laboratory Pollutant Assessments Group in Grand Junction, Colo., with this project. The objective was to determine whether or not radioisotopes possibly associated with past Department of Defense (DOD) operations were present and within accepted background levels. The radiation survey was accomplished by performing three independent radiation surveys, both outdoors and indoors, and random soil sampling. Initially, the site was land surveyed to develop a grid block system. A background radiation investigation was performed out in the San Pedro area.

311

Reborn quadrant anode image sensor  

International Nuclear Information System (INIS)

We describe a position sensitive photon counting microchannel plate based detector with an improved quadrant anode (QA) readout system. The technique relies on a combination of the four planar elements pattern and an additional fifth electrode. The charge cloud induced by single particle detection is split between the electrodes. The measured charge values uniquely define the position of the initial event. QA has been first published in 1976 by Lampton and Malina. This anode configuration was undeservedly forgotten and its potential has been hardly underestimated. The presented approach extends the operating spatial range to the whole sensitive area of the microchannel plate surface and demonstrates good linearity over the field of view. Therefore, the novel image sensor results in spatial resolution better then 50?m and count rates up to one million events per second.

2009-06-01

312

Reborn quadrant anode image sensor  

British Library Electronic Table of Contents (United Kingdom)

We describe a position sensitive photon counting microchannel plate based detector with an improved quadrant anode (QA) readout system. The technique relies on a combination of the four planar elements pattern and an additional fifth electrode. The charge cloud induced by single particle detection is split between the electrodes. The measured charge values uniquely define the position of the initial event. QA has been first published in 1976 by Lampton and Malina. This anode configuration was undeservedly forgotten and its potential has been hardly underestimated. The presented approach extends the operating spatial range to the whole sensitive area of the microchannel plate surface and demonstrates good linearity over the field of view. Therefore, the novel image sensor results in spatial...

2009-01-01

313

Real time study of the crystallization of aluminium-base icosahedral phases by neutron powder diffraction  

International Nuclear Information System (INIS)

The thermal transformation of Al-base icosahedral phases was studied in-situ by real time neutron powder diffraction. Different compositions have been selected in order to vary the initial phase morphology and change the neutron scattering contrast between species. Alloys with low silicon and large aluminium contents produce first the orthorhombic O-Al_6Mn modification. In alloys with larger silicon content, the #alpha#-AlMnSi cubic phase appears soon after the beginning of the transformation but is still preceeded by O-Al_6Mn. Depending on compositions, the crystallization of the icosahedral phase is controlled either by the diffusion of Al through its interface with the residual fcc aluminium or that of Si within the bulk. The results are discussed in the light of current structural models. (author) 40 refs., 14 figs., 3 tabs.

1987-01-01

314

Radioactive waste disposal for fission and fusion reactors  

Energy Technology Data Exchange (ETDEWEB)

The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only material out of reactor at least one year is considered. The total activity in Ci/W(th) of the Starfire tokamak is slightly greater than that of the PWR during the active lifetimes of the two reactors and beyond 1000 years. However, using reduced activation materials in Starfire can result in about 1/2000 as much long-lived radioactivity as in the fission reactor. It is stressed that comparison of wastes on this basis is not straightforward, since the radioisotopes and methods required for their disposal are different for fusion and fission reactors. 2 refs., 1 fig., 2 tabs.

1989-01-01

315

Polymer-metal complex as gel electrolyte for quasi-solid-state dye-sensitized solar cells  

International Nuclear Information System (INIS)

A kind of polymer-metal complex gel electrolyte is successfully prepared and is used in dye-sensitized solar cells. Raman and X-ray photoelectron spectroscopy confirm the structure of this complex and is found that the metal ion reacts with nitrogen in the polymer. This novel electrolyte shows apparent diffusion coefficient of iodide of 8.37 x 10-7 cm2 s-1 and the energy conversion efficiency of 6.10% when the amount of ZnI2 is 0.04 M. By studying the dissociation active energy of the inorganic salt in electrolytes, we find that the metal salts can dissociate more easily after reacting with polymer and as a result can provide extra free iodide ion. The cell maintains ca. 93% of its initial efficiency after 20 d without further sealing, which shows good long-time stability.

2011-01-01

316

Penile rehabilitation therapy with PDE-V inhibitors following radical prostatectomy: proceed with caution.  

Science.gov (United States)

Penile rehabilitation therapy following radical prostatectomy is a much debated topic. Erectile dysfunction is still a significant contributor to postoperative morbidity following radical prostatectomy, despite meticulous nerve-sparing technique. Secondary smooth muscle changes in the penis have been identified as the underlying causes of penile atrophy, veno-occlusive dysfunction, and fibrosis. Initial observations that intracavernous injection therapies used on a regular basis postoperatively resulted in improvements in the return of spontaneous erectile function led to the development of penile rehabilitation protocols. Chronic dosing of PDE-V inhibitors is now commonly used by urologists after radical prostatectomy. Despite the current enthusiasm of penile rehabilitation therapy, current scientific evidence with clinical trials is still limited. PMID:19255627

2009-01-25

317

Pd adsorption on Si(1 1 3) surface: STM and XPS study  

Energy Technology Data Exchange (ETDEWEB)

Pd-induced surface structures on Si(1 1 3) have been studied by scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). In the initial process of the Pd adsorption below 0.10 ML, Pd silicide (Pd{sub 2}Si) clusters are observed to form randomly on the surface. By increasing the Pd coverage to 0.10 ML, the clusters cover the entire surface, and an amorphous layer is formed. After annealing the Si(1 1 3)-Pd surface at 600 deg. C, various types of islands and chain protrusions appears. The agglomeration, coalescence and crystallization of these islands are observed by using high temperature (HT-) STM. It is also found by XPS that the islands correspond to Pd{sub 2}Si structure. On the basis of these results, evolution of Pd-induced structures at high temperatures is in detail discussed.

2008-09-30

318

PSA for CANDU-6 pressurized heavy water reactors: Wolson Units 2,3 and 4 of Korea  

International Nuclear Information System (INIS)

Level 1 and 2 probabilistic safety assessments (PSAs) for both internal and external events are being performed to meet one of the conditions for a construction permit for Wolsong units 2, 3, and 4 in Korea. These units are CANDU-6 Pressurized Heavy Water Reactors (PHWRs), and the study is the first comprehensive level 1 and 2 PSAs for CANDU type plants in the world. The detailed PSA includes and extensive fault tree, event tree analysis, human reliability analysis, and common cause failure analysis. Event trees have been developed for 35 internal initiating event groups. The preliminary results show that the total core damage frequency for Wolsong units 2, 3, and 4 each is similar to that for a typical PWR plant. (author).

1997-06-01

319

PET/MRI hybrid imaging: devices and initial results  

British Library Electronic Table of Contents (United Kingdom)

The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest...

2008-01-01

320

Numerical simulation of fluid flow and heat transfer in a concentric tube heat exchanger  

International Nuclear Information System (INIS)

In this paper, numerical simulation of a concentric tube heat exchanger is presented to determine the convective heat transfer coefficient and friction factor in a smooth tube. Increasing the convective heat transfer coefficient can increase heat transfer rate in a concentric tube heat exchanger from a given tubular surface area. This can be achieved by using heat transfer augmentation devices. This work constitutes the initial phase of the numerical simulation of heat transfer from tubes employing augmentation devices, such as twisted tapes, wire-coil inserts, for heat transfer enhancement. A computational fluid dynamics (CFD) simulation tool was developed with CFX software and the results obtained from the simulations are validated with the empirical correlations for a smooth tube heat exchanger. The difficulties associated with the simulation of a heat exchanger augmented with wire-coil inserts are discussed. (author)

2003-05-28

321

Numerical simulation of coalbed methane generation, dissipation and retention in SE edge of Ordos Basin, China  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a numerical study on the formation history of coalbed methane (CBM) reservoir in the southeast edge of Ordos Basin, China. The coal seams studied belong to the Late Palaeozoic coal-bearing series. These coal seams have a burial history and experienced the process of subsidence, rapid subsidence alternated with uplift and then uplift, sequentially, and underwent the geothermal actions at normal, extremely high, and then normal temperatures, respectively. Coal organic matter of the coal seams matured in the Triassic Period and in the Late Jurassic to Early Cretaceous Period. The results from numerical simulation reveal that CBM reservoir evolution history can be classified into five stages, namely primary, initial, stagnant, active and dissipative stages. In the first (pr...

2010-01-01

322

Mutual interactions of two planetary objects in a protoplanetary accretion disc: 2D SPH simulations .  

Science.gov (United States)

We present here a study based on the migration of protoplanets in an accretion disc of a forming star, as the mainly proposed scenario for the formation of planetary systems. Attention is here focused on the mutual interactions between two protoplanets, both embedded in the accretion disc, as a function of the protoplanets masses, their relative positions, the dynamic properties of the accretion disc particles. The study is performed through a 2D SPH code and preliminary results show an oscillation of the distance between the two protoplanets, together with a slow migration of the two planets towards the central star when two Jupiter-like planets are considered. Less correlated behaviour is observed when at least one of the two protoplanets has an Earth-like mass. The role played by the disc particles initial angular momentum is discussed.

2010-01-01

323

Mottling score predicts survival in septic shock  

British Library Electronic Table of Contents (United Kingdom)

Background Experimental and clinical studies have identified a crucial role of microcirculation impairment in severe infections. We hypothesized that mottling, a sign of microcirculation alterations, was correlated to survival during septic shock. Methods We conducted a prospective observational study in a tertiary teaching hospital. All consecutive patients with septic shock were included during a 7-month period. After initial resuscitation, we recorded hemodynamic parameters and analyzed their predictive value on mortality. The mottling score (from 0 to 5), based on mottling area extension from the knees to the periphery, was very reproducible, with an excellent agreement between independent observers [kappa?=?0.87, 95% CI (0.72?0.97)]. Results Sixty patients were included. The SOFA scor...

2011-01-01

324

Modeling of MeV alpha particle energy transfer to lower hybrid waves  

Energy Technology Data Exchange (ETDEWEB)

The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. An initial analytic study was done by Fisch and Rax. Here the authors calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favorable for wave amplification from alpha energy. They find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. This technique is ...

1993-10-01

325

Membrane barriers for radon gas flow restrictions  

International Nuclear Information System (INIS)

Research was performed to assess the feasibility of barrier membrane substances, for use within mining or associated high risk environments, in restricting the diffusion transport of radon gas quantities. Specific tests were conducted to determine permeability parameters of a variety of membrane materials with reference to radon flow capabilities. Tests were conducted both within laboratory and in-situ emanation environments where concentrations and diffusion flows of radon gas were known to exist. Equilibrium radon gas concentrations were monitored in initially radon-free chambers adjacent to gas sources, but separated by specified membrane substances. Membrane barrier effectiveness was demonstrated to result in reduced emanation concentrations of radon gas within the sampling chamber atmosphere. Minimum gas concentrations were evidenced where the barrier membrane material was shown to exhibit lowest radon permeability characteristics.

326

Marker experiments in growth studies of Ni_2Si, Pd_2Si, and CrSi_2 formed both by thermal annealing and by ion mixing  

International Nuclear Information System (INIS)

Inert markers (evaporated tungsten and silver) were used in growth studies of silicides formed both by thermal annealing and by ion mixing in the Ni/Si, Pd/Si, and Cr/Si systems. The markers were initially imbedded inside silicides and backscattering spectrometry was used to determine the marker displacement after different processing conditions. The results obtained in thermal annealing are quite consistent with that found in previous investigations. Ni is the dominant diffusing species in Ni_2Si, while Si is the diffusing species in CrSi_2. In Pd_2Si, both Pd and Si are moving species with Pd the faster of the two. In contrast, in growth of silicides by ion irradiation Si is the faster diffusing species in all three systems.

327

Marker experiments in growth studies of Ni/sub 2/Si, Pd/sub 2/Si, and CrSi/sub 2/ formed both by thermal annealing and by ion mixing  

Energy Technology Data Exchange (ETDEWEB)

Inert markers (evaporated tungsten and silver) were used in growth studies of silicides formed both by thermal annealing and by ion mixing in the Ni/Si, Pd/Si, and Cr/Si systems. The markers were initially imbedded inside silicides and backscattering spectrometry was used to determine the marker displacement after different processing conditions. The results obtained in thermal annealing are quite consistent with that found in previous investigations. Ni is the dominant diffusing species in Ni/sub 2/Si, while Si is the diffusing species in CrSi/sub 2/. In Pd/sub 2/Si, both Pd and Si are moving species with Pd the faster of the two. In contrast, in growth of silicides by ion irradiation Si is the faster diffusing species in all three systems.

1985-08-15

328

Management of young onset colorectal cancer: divergent practice in the East of England  

British Library Electronic Table of Contents (United Kingdom)

Abstract Aim- According to the revised Bethesda Guidelines, colorectal cancer (CRC) occurring under age 50-years should be screened to exclude Lynch syndrome. However, in current practice in East Anglia, tumour screening is initiated only after genetics referral, reserved for those with a strong pedigree. This study aimed to determine how many patients with young-onset CRC undergo tumour screening in hospitals in East Anglia. Method- A retrospective case notes review over 5-years in four hospitals was undertaken to determine what proportion of those with young-onset CRC underwent referral for tumour screening and to assess local practices in terms of patient counselling and management. Results- One hundred and twenty-two patients were included. There was an average yearly caseload of 6-9 p...

2011-01-01

329

Lithium isotopic separation: preliminary studies; Separacao isotopica de litio: estudos preliminares  

Energy Technology Data Exchange (ETDEWEB)

In order to get the separation of natural isotopes of lithium by electrolytic amalgamation, an electrolytic cell with a confined mercury cathode was used to obtain data for the design of a separation stage. The initial work was followed by the design of a moving mercury cathode electrolytic cell and three experiments with six batches stages were performed for the determination of the elementary separation factor. The value obtained, 1.053, was ill agreement: with the specialized literature. It was verified in all experiments that the lithium - 6 isotope concentrated in the amalgam phase and that the lithium - 7 isotope concentrated in the aqueous phase. A stainless-steel cathode for the decomposition of the lithium amalgam and the selective desamalgamation were also studied. In view of the results obtained, a five stages continuous scheme was proposed. (author)

1998-07-01

330

Large (≥2cm) non-hypervascular nodules depicted on MRI in the cirrhotic liver: fate and implications  

British Library Electronic Table of Contents (United Kingdom)

Aim To determine the fate and clinical implication of large (?2cm), non-hypervascular nodules depicted on magnetic resonance imaging (MRI) in the cirrhotic liver. Materials and methods In 21 patients with cirrhosis (14 hepatitis B, two ethanol abuse, four cryptogenic, one Wilson's disease), 25 large (?2cm in the longest dimension) non-hypervascular nodules were identified on dynamic MRI. The implications for diagnosis of the initial size, contour, and signal characteristics on MRI in addition to patients' age and cause of cirrhosis were assessed in our analysis. Results Twelve (75%) out of 16 lesions were malignant or potentially-malignant from 14 hepatitis B patients, while seven (78%) of the nine lesions from other patients were benign (p=0.016). The mean age of the patients who ha...

2008-01-01

331

Kinetic and mass transfer analyses of metal biosorption by Caulerpa lentillifera  

British Library Electronic Table of Contents (United Kingdom)

This study examined kinetics and mass transfer in the biosorption of heavy metals onto Caulerpa lentillifera. The sorption capacity of Cu^2^+, Pb^2^+ and Cd^2^+ from aqueous solution increased with initial metal concentration and decreased with biosorbent dose. Kinetic data were well described using the pseudo-second-order model. Results showed that both external mass transfer and intraparticle diffusion were rate limiting steps in the biosorption process. Activation energy of biosorption kinetics fell in the range of 3-13kJ/mol. The biosorption of Cu^2^+, Cd^2^+ and Pb^2^+ on the biomass correlated well with the Langmuir isotherm (R^2>0.99) with maximum sorption capacities at 293K of 0.169, 0.085 and 0.177mol/kg for Cu^2^+, Cd^2^+ and Pb^2^+ ions, respectively. Thermodynamic studies demon...

2011-01-01

332

Is hyperhomocysteinemia an Alzheimer's disease (AD) risk factor, an AD marker, or neither?  

British Library Electronic Table of Contents (United Kingdom)

Alzheimer's disease (AD) is the most common form of neurodegenerative disease. The vast majority cases of AD are sporadic, without clear cause, and a combination of environmental and genetic factors has been implicated. The hypothesis that homocysteine (Hcy) is a risk factor for AD was initially prompted by the observation that patients with histologically confirmed AD had higher plasma levels of Hcy, termed hyperhomocysteinemia (HHcy), than age-matched controls. Most evidence accumulated so far implicates HHcy as a risk factor for AD onset, but there are also conflicting results. In this review we summarize reports on the relationship between HHcy and AD from epidemiological investigations, including observational studies and randomized controlled clinical trials. We also examine recent i...

2011-01-01

333

Ion-induced phase formation in metal-silicon systems. [Xenon ion implantation effects  

Energy Technology Data Exchange (ETDEWEB)

By using megaelectronvolt /sup 4/He ion backscattering techniques and transmission electron microscopy, the authors have investigated the interactions of ion beams with thin film structures in a number of silicide-forming systems. The mixed layer was found to be an equilibrium compound for near-noble metals and an amorphous phase for refractory metals. Differences in behavior have also been observed in near-noble metal systems. For palladium, the Pd/sub 2/Si phase grew with ion dose and remained crystalline up to high dose. For nickel, the compound Ni/sub 2/Si was formed initially and became amorphous on prolonged irradiation. All the results indicate the significance of atomic mobility at target temperatures in determining the phase formation and in explaining the sensitivity of the silicides to ion bombardment.

1985-01-11

334

Ion-induced phase formation in metal-silicon systems  

International Nuclear Information System (INIS)

By using megaelectronvolt "4He ion backscattering techniques and transmission electron microscopy, the authors have investigated the interactions of ion beams with thin film structures in a number of silicide-forming systems. The mixed layer was found to be an equilibrium compound for near-noble metals and an amorphous phase for refractory metals. Differences in behavior have also been observed in near-noble metal systems. For palladium, the Pd_2Si phase grew with ion dose and remained crystalline up to high dose. For nickel, the compound Ni_2Si was formed initially and became amorphous on prolonged irradiation. All the results indicate the significance of atomic mobility at target temperatures in determining the phase formation and in explaining the sensitivity of the silicides to ion bombardment. (Auth.).

335

Intermediate Strain-Rate Loading Experiments - Technique and Applications to Ceramics  

Energy Technology Data Exchange (ETDEWEB)

A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.

1999-08-16

336

Innovative wind turbines. Circulation controlled vertical axis wind turbine. Progress report, March 1-December 31, 1976  

Science.gov (United States)

Theoretical and experimental research efforts in evaluating an innovative concept for vertical axis wind turbines (VAWT) are described. The concept is that of using straight blades composed of circulation controlled airfoil sections. The theoretical analysis has been developed to determine the unsteady lift and moment characteristics of multiple-blade cross-flow wind turbines. To determine the drag data needed as input to the theoretical analysis, an outdoor test model VAWT has been constructed; design details, instrumentation, and calibration results are reported. Initial testing is with fixed pitch blades having cross-sections of conventional symmetrical airfoils. Costs of building the test model are included, as well as estimates for blades constructed with composite materials. These costs are compared with those of other types of wind turbines.

1978-10-01

337

Initial airborne CO{sub 2} DIAL measurements: Discussion of results and data analysis considerations  

Energy Technology Data Exchange (ETDEWEB)

A detailed discussion of airborne CO{sub 2}, DIAL measurements obtained from the first joint N-ABLE field campaign at INEL is presented. System performance characteristics, including return signal strength, averaging statistics, and temporal correlation as well as multi-line DIAL spectral data are discussed. In particular, we review data acquisition and analysis strategies pertinent to chemical detection from a moving platform, such as range determination and correction, and return signal processing (waveform vs. box-car integration, baseline correction). We also report observed effects and variations due to near-field light scattering, pointing and tracking stability, and stack-release plume dynamics.

1997-07-01

338

Influence of sulfur dioxide content of 20% and 92% sulfuric acid on anodic behavior of stainless steels  

Energy Technology Data Exchange (ETDEWEB)

This paper investigates steels 12Kh18N10T, 10Kh17N13M2T, 08Kh22N6T, and 08Kh21N6M2T. In corrosion of stainless steels in sulfuric acid solutions, dissolved sulfur dioxide acts as a cathodic depolarizer, capable of being reduced to elemental sulfur or forming sulfides with the metal. Depending on the conditions, this is associated with some increase in potential and greater or lesser increase in corrosion or facilitation of passivation of active steel. After passivation the influence of SO/sub 2/ is negligible. The results of this investigation were used as initial data for developing systems of anodic protection for shell-and-tube heat exchangers for sulfuric acid.

1986-07-01

339

Impact properties of low alloy TRIP steels; Teigokin TRIP ko no shogeki tokusei  

Energy Technology Data Exchange (ETDEWEB)

The impact properties of high-strength low alloy TRIP steels such as 'TRIP-aided dual-phase steel' and 'TRIP-aided bainitic steel' associated with the transformation-induced plasticity (TRIP) of retained austenite were investigated for some applications to the automotive impact members. The TRIP steels possessed far higher impact absorbed value and lower ductile-brittle transition temperature than the conventional ferrite-martensite and ferrite-pearlite steels. The stress relaxation resulting from the strain-induced transformation of retained austenite islands or films improved the impact properties in terms of suppressing void and/or crack initiation and these propagation. The best impact properties were completed in the steel composing of uniform fine bainitic lath structure and a large amount of stable interlath retained austenite films. (author)

2000-08-01

340

Human factors assessments of innovative technologies: Robotics sector  

International Nuclear Information System (INIS)

The U.S. Department of Energy (DOE) has funded major environmental technology developments over the past several years. One area that received significant attention is robotics, which has resulted in the development of a wide range of unique robotic systems tailored to the many tasks unique to the DOE complex. These systems are often used in highly hazardous environments, which reduces or eliminates worker exposures. The DOE, concurrent with the technology development initiative, also established and funded a 5-yr cooperative agreement intended to interface with the technology development community-with specific attention to the occupational safety and health aspects associated with individual technologies through human factors and hazard assessments. This program is now in its third year.

1997-11-16

341

Gouge initiation in high-velocity rocket sled testing  

Energy Technology Data Exchange (ETDEWEB)

A model is presented which describes the formation of surface damage ``gouging`` on the rails that guide rocket sleds. An unbalanced sled can randomly cause a very shallow-angle, oblique impact between the sled shoe and the rail. This damage phenomenon has also been observed in high-velocity guns where the projectile is analogous to the moving sled shoe and the gun barrel is analogous to the stationary rail. At sufficiently high velocity, the oblique impact will produce a thin hot layer of soft material on the contact surfaces. Under the action of a normal moving load, the soft layer lends itself to an anti-symmetric deformation and the formation of a ``hump`` in front of the moving load. A gouge is formed when this hump is overrun by the sled shoe. The phenomenon is simulated numerically using the CTH strong shock physics code, and the results are in good agreement with experimental observation.

1994-07-01

342

Gluino-Squark Production at the LHC: The Threshold  

CERN Document Server

An analysis of the cross section for hadronic production of gluino-squark pairs close to threshold is presented. Within the framework of non-relativistic QCD a significant enhancement compared to fixed order perturbation theory is observed which originates from the characteristic remnants of the gluino-squark resonances below the nominal pair threshold. The analysis includes all colour configurations of S-wave gluino-squark pairs, i.e. triplet, sextet and 15 representation. Matching coefficients at leading order are separately evaluated for all colour configurations. The dominant QCD corrections, arising from initial- and final-state radiation are included. The non-relativistic dynamics of the gluino pair is solved by calculating the Green's function in Next-to-Leading Order (NLO). The results are applied to benchmark scenarios, based on Snowmass Points and Slopes (SPS). As a consequence of the large decay rate of at least one of the ...

2011-01-01

343

Geometry of elastic hydrofracturing by injection of an over pressured non-Newtonian Fluid  

CERN Document Server

The nucleation and propagation of hydrofractures by injection of over pressured fluids in an elastic and isotropic medium are studied experimentally. Non-Newtonian fluids are injected inside a gelatine whose mechanical properties are assumed isotropic at the experimental strain rates. Linear elastic theory predicts that plastic deformation associated to breakage of gelatin bonds is limited to a small zone ahead of the tip of the propagating fracture and that propagation will be maintained while the fluid pressure exceeds the normal stress to the fracture walls (Ch\\'avez-\\'Alvarez,2008) (i.e., the minimum compressive stress), resulting in a single mode I fracture geometry. However, we observed the propagation of fractures type II and III as well as nucleation of secondary fractures, with oblique to perpendicular trajectories with respect to the initial fracture. In the Video (http://hdl.handle.net/1813/14122) experimental evidence shows that ...

2009-01-01

344

Gamow-Teller #beta#-transition from the 2"- ground state of "8"8Rb to the 3"- excited state of "8"8Sr  

International Nuclear Information System (INIS)

The Gamow-Teller #beta#-transition from the ground state 2"- of "8"8Rb to the 3"- level at 2.734 MeV of "8"8Sr is studied. The nuclear matrix element and the log ft value are calculated using complete nuclear wave functions for the initial and final states. It is shown that, contrary to the normal assumption, the component of the final state does give a very important contribution to due to the presence of strong cancellation effects. Although our calculations favour a wave function for the 3"- level "8"8Sr where neutron 1h-1p configurations are not included, there are still some facts which make that our results cannot be taken as conclusive. (orig.).

345

Flame propagation characteristics and flame structures of zirconium particle cloud in a small-scale chamber  

British Library Electronic Table of Contents (United Kingdom)

Flame propagating through zirconium particle cloud in a small-scale vertical rectangle chamber was investigated experimentally. In the experiments, the zirconium quoted 99% purity was used and the diameter of particles was distributed 1?22 ?m. The zirconium dust was dispersed into the chamber by air flow and ignited by an electrode spark. A high-speed video camera was used to record the images of the propagating flame. Micro-thermocouples, schlieren optical system and microscopic lens were used to obtain temperature profiles and flame structure, respectively. Based on the experimental results, flame propagation characteristics and flame structure of zirconium particle cloud were analyzed. The propagation velocity of the flame is quite slow in the initial 14 ms and then accelerates to maxim...

2010-01-01

346

Five-year Changes in Periodontal Parameters after Apical Surgery  

British Library Electronic Table of Contents (United Kingdom)

IntroductionMost clinical studies on the outcome of apical surgery concentrate on periapical healing based on radiographic and clinical characteristics (signs and symptoms). This study focuses on long-term changes in periodontal parameters after apical surgery. MethodsPeriodontal parameters (ie, probing depth [PD], level of gingival margin [GM], and calculated clinical attachment level [CAL]) were collected at baseline and at 1 and 5 years after apical surgery. Changes in PD, GM, and CAL were calculated over time and were also evaluated in relation to patient-, tooth-, and treatment-related covariables. ResultsOne hundred eighty-six of 242 initially identified teeth could be evaluated. Significant changes in GM and CAL were observed at facial sites during the first year after surgery (mean...

2011-01-01

347

Fission neutron damage rates and efficiencies in several metals  

International Nuclear Information System (INIS)

Initial rates of resistivity-measured low-temperature damage production by fission-spectrum fast neutrons have been determined for 14 metals in the same very well characterized irradiation facility. Six of these metals were fcc, 5 bcc, and 3 hcp. Most were of quite high purity. Observed damage rates, after correction for all known extraneous resistivity-producing effects, were compared with rates predicted by the damage calculation code RECOIL, using parameters chosen from the literature. These parameters, effective displacement threshold energy, E/sub d/, and Frenkel-pair resistivity, rho/sub F/, were in many cases only best estimates, the further refinement of which may be aided by the present results. Damage efficiencies (measured/predicted rates) follow the same trends by crystal classes as seen in other fast-neutron studies.

2003-04-01

348

First ICRF heating experiment in the large helical device  

Energy Technology Data Exchange (ETDEWEB)

Initial ICRF heating experiment in the LHD was carried out in 1998. One pair of the movable loop antennas was used and the coupling resistance was around one ohm for the low density ECH plasma. The loading characteristics were consistent with the fast wave excitation. By applying the ICRF heating of 300 kW to the ECH target plasma, the diamagnetic energy was increased from 13 kJ to 26 kJ. The heating performance was decided by hydrogen mixture rate on puffing gas. Efficient electron heating was observed at the higher hydrogen gas ratio. These results can be explained by the one dimensional wave analysis calculation on slab plasma model. (J.P.N.)

1999-07-01

349

Fatigue and creep-fatigue testing of steam filled tubular Alloy 800 specimens  

Energy Technology Data Exchange (ETDEWEB)

A test program was conducted under contract to Sandia National Laboratories to investigate water/steam effects on elevated temperature low cycle fatigue and creep-fatigue of Alloy 800. This report presents interpretation and analysis of the test results. Tubular specimens with water sealed inside were cycled to failure under strain control. Tests were conducted to 616K (650/sup 0/F) and 922K (1200/sup 0/F); some at 922K included tensile or compressive hold periods to simulate creep-fatigue conditions. The tubular specimens showed significantly lower lives than solid bar specimens cycled at equivalent strain ranges. Rough internal surfaces contributed to early crack initiation with these specimens. Inclusion of hold periods caused further large reductions in cycles to failure.

1982-05-01

350

Experimental and analytical studies of pipe whip tests under PWR LOCA conditions  

Energy Technology Data Exchange (ETDEWEB)

A series of pipe rupture tests has been performed at JAERI to demonstrate the safety of primary coolant circuits in the event of pipe rupture in nuclear power plants. Pipe whip tests and jet discharge tests have been conducted under BWR and PWR loss-of-coolant accident (LOCA) conditions. The present paper describes the experimental and analytical results of the pipe whip tests performed under PWR LOCA conditions using 4, 6 and 8-inch test pipes. The tests were carried out at an initial pressure and temperature of 15.7 MPa and 325/sup 0/C, respectively. Moreover, a dynamic analysis of pipe whip tests was carried out using the general purpose finite element programm ADINA.

1987-09-01

351

Evolutionary developments advancing the floating production, storage, and offloading concept  

Energy Technology Data Exchange (ETDEWEB)

Tanker-based floating production, storage and offloading (FPSO) systems have been in operation since Aug. 1977, when a single-well FPSO was put into production by Shell Espana in the Mediterranean. The overall operational experience with this system at this field is reviewed. Special attention is directed to the wireline workover facilities which have proven to be satisfactory. A subsequent evolutionary step, a FPSO accommodating multiple wells, necessitated development of a multiple-bore product swivel. A design program for this swivel was initiated in 1978, a prototype was built and fullscale testing finalized in 1980. A summary of the test results is presented. Simultaneous with the multiple-bore swivel development, detailed engineering for an 8-well FPSO was begun. This sytem includes gas lift a

1982-01-01

352

Evaluation of minderal resource potential, Caldera geology, and volcano-tectonic framework at and near Yucca Mountain, Task 3  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the results of Task 3 work that was initially discussed in our monthly reports for the period October 1, 1992 through September 30, 1993, and contained in our various papers and abstracts, both published and currently in press or in review. Our work during this period was involved (a) the continuation of studies begun prior to October, 1992, focussed mainly on aspects of the caldera geology, volcanic stratigraphy, magmatic activity, hydrothermal mineralization and extensional tectonics of the western and northwestern parts of the southwestern and Nevada volcanic field (SWNVF), studies of the subsurface rocks of Yucca Mountain utilizing drill hole samples obtained in 1991 and 1992, and (b) new studies of veins and siliceous rocks cropping out in northwestern Yucca Mountain that provide evidence for previously unrecognized hydrothermal activity during the Crater Flat Tuff period of volcanism.

1993-09-30

353

Energy saver A-sector power test results  

Energy Technology Data Exchange (ETDEWEB)

The superconducting magnets and associated cryogenic components in A-sector represent the initial phase of installation of the Fermilab superconducting accelerator, designed to accelerate proton beams to energies of 1 TeV. Installation of the magnets, comprising one-eighth of the ring, was completed in December, 1981. Cooldown and power tests took place in the first half of 1982, concurrent with main ring use for 400 GeV high energy physics. The tests described in this paper involved 151 cryogenic components in the tunnel: 94 dipoles, 24 quadrupoles, 25 spool pieces, 3 feed cans, 4 turn-around boxes and 1 bypass. Refrigeration was supplied by three satellite refrigerators, the Central Helium Liquefier, and two compressor buildings. The magnets were powered by a single power supply.

1982-09-15

354

Electron binding to isolated polar molecules and molecular dipole assemblies  

International Nuclear Information System (INIS)

In a sufficiently large cluster of several polar molecules, collective interactions lead to localization or 'solvation' of electrons. The existence of the solvated electron is known since 1863 in liquid ammonia and since 1962 for liquid water. In 1984, electron localization in clusters was experimentally demonstrated in (H_2O)_N_#>=#_1_1 and (NH_3)_N_#>=#_3_4 clusters. In cooperation with K. Bowen, we recently initiated a test of the theory of electron binding by a dipole and a new ground state dipole bound dimer anion, (H_2O..NH_3), was predicted and observed. We here describe results of a search for new dipole-bound and solvated electron systems. (author).

1994-03-20

355

Electrolytic membrane formation of fluoroalkyl polymer using a UV-radiation-based grafting technique and sulfonation  

Science.gov (United States)

A sulfonated fluoroalkyl graft polymer (FGP) membrane was prepared as a polymer electrolyte. First, the FGP membrane was grafted with styrene under UV irradiation. The grafted FGP was then sulfonated to functionalize it for proton conductivity. The grafting degree of the membrane increased with increasing grafting time during UV irradiation. The proton conductivity of the membrane increased with increasing grafting degree. The swelling ratio was independent of the grafting time, however, the water uptake increased with increasing grafting degree. Based on these results, it was found that the UV-initiated styrene grafting occurred along the membrane thickness direction. Moreover, the membrane was embedded within the glass fibers of the composite. This composite electrolytic membrane had 1.15 times the proton conductivity of a Nafion 117 membrane.

2011-03-01

356

Effects of coolant chemistry on corrosion of 3003 aluminum alloy in automotive cooling system  

British Library Electronic Table of Contents (United Kingdom)

In this work, effects of coolant chemistry, including concentrations of chloride ions and ethylene glycol and addition of various ions, on corrosion of 3003 Al alloy were investigated by electrochemical impedance spectroscopy measurements and scanning electron microscopy characterization. In chloride-free, ethylene glycol-water solution, a layer of Al-alcohol film is proposed to form on the electrode surface. With the increase of ethylene glycol concentration, more Al-alcohol film is formed, resulting in the increase in film resistance and charge-transfer resistance. In the presence of Cl- ions, they would be involved in the film formation, decreasing the stability of the film. In 50% ethylene glycol-water solution, the threshold value of Cl- concentration for pitting initiation is within ...

2010-01-01

357

Effect of Sb addition on the creep property of AZ31 alloy  

Energy Technology Data Exchange (ETDEWEB)

The effects of antimony addition on the microstructures and creep behavior of AZ31 have been studied. Constant load creep tests were carried out at 200 C and an initial stress of 50MPa for AZ31 alloys containing antimony up to 0.84% by weight. Results show that Small additions of antimony to AZ31 effectively decreased the creep extension and steady state creep rates. The steady state creep rate of AZ31 was reduced 2.5 times by the addition of 0.84% of antimony by weight. The main reason for the higher creep resistance is due to the presence of high volume fraction ({proportional_to} 20%) of second phases including Mg{sub 3}Sb{sub 2}, which effectively hindered the movement of dislocations during the elevated temperature creep. (orig.)

2004-07-01

358

Effect of Nisin?s Controlled Release on Microbial Growth as Modeled for Micrococcus luteus  

British Library Electronic Table of Contents (United Kingdom)

The need for safe food products has motivated food scientists and industry to find novel technologies for antimicrobial delivery for improving food safety and quality. Controlled release packaging is a novel technology that uses the package to deliver antimicrobials in a controlled manner and sustain antimicrobial stress on the targeted microorganism over the required shelf life. This work studied the effect of controlled release of nisin to inhibit growth of Micrococcus luteus (a model microorganism) using a computerized syringe pump system to mimic the release of nisin from packaging films which was characterized by an initially fast rate and a slower rate as time progressed. The results show that controlled release of nisin was strikingly more effective than instantly added (?formulated...

2011-01-01

359

Dynamical Quasi-Stationary States in a system with long-range forces  

CERN Document Server

The Hamiltonian Mean Field model describes a system of N fully-coupled particles showing a second-order phase transition as a function of the energy. The dynamics of the model presents interesting features in a small energy region below the critical point. In particular, when the particles are prepared in a ``water bag'' initial state, the relaxation to equilibrium is very slow. In the transient time the system lives in a dynamical quasi-stationary state and exhibits anomalous (enhanced) diffusion and L\\'evy walks. In this paper we study temperature and velocity distribution of the quasi-stationary state and we show that the lifetime of such a state increases with N. In particular when the $N\\to \\infty$ limit is taken before the $t \\to \\infty$ limit, the results obtained are different from the expected canonical predictions. This scenario seems to confirm a recent conjecture proposed by C.Tsallis.

2001-01-01

360

Dye Removal, Energy Consumption and Operating Cost of Electrocoagulation of Textile Wastewater as a Clean Process  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this research, the efficiency of electrocoagulation treatment process using aluminum electrodes to treat synthetic wastewater containing Reactive Red198 (RR198) was studied. The effects of parameters such as voltage, time of reaction, electrode connection mode, initial dye concentration, electrolyte concentration, and inter electrode distance on dye removal efficiency were investigated. In addition, electrical energy consumption, electrode consumption, and operating cost at optimum condition have been investigated. The results showed that dye and chemical oxygen demand removals were 98.6 and 84%, respectively. Electrode consumption, energy consumption and operating cost were 0.052-kg/m3, 1.303-kWh/m3 and 0.256-US$/m3, respectively. Dye removal kinetic followed first order kinet...

2011-01-01

361

Dissipative dynamics of circuit-QED in the mesoscopic regime  

CERN Document Server

We investigate the behavior of a circuit QED device when the resonator is initially populated with a mesoscopic coherent field. The strong coupling between the cavity and the qubit produces an entangled state involving mesoscopic quasi-pointer states with respect to cavity dissipation. The overlap of the associated field components results in collapse and revivals for the Rabi oscillation. Although qubit relaxation and dephasing do not preserve these states, a simple analytical description of the dissipative dynamics of the circuit QED device including cavity relaxation as well as qubit dissipation is obtained from the Monte-Carlo approach. Explicit predictions for the spontaneous and induced Rabi oscillation signals are derived and sucessfully compared with exact calculations. We show that these interesting effects could be observed with a 10 photon field in forthcoming circuit QED experiments.

2007-01-01

362

Direct coal liquefaction using iron-titanium hydride as a hydrogen distribution and catalytic material. Quarterly report No. 2, December 1, 1984-February 28, 1985  

Science.gov (United States)

During this reporting period the experimental apparatus was completed after substantial delays by the manufacturer. The equipment has been fully tested to familiarize the staff with its operating and safety procedures. An initial liquefaction study has begun on samples of Utah coal (60 microns or less) using 50 grams of iron-titanium alloy, 500 ml of tetralin, and 150 grams of powdered coal at 500/sup 0/F and 500 psig. Results will be available in the next quarterly report. A new researcher has been added to the project to address the hydrogen absorption of new and recycled alloy samples. 2 figs.

1985-03-28

363

Diffusion modeling of ion implanted boron in Si during RTA: Correlation of extended defect formation and annealing with the enhanced diffusion of boron  

International Nuclear Information System (INIS)

Accurate modeling of the enhanced diffusion of boron during rapid thermal annealing has been accomplished by incorporating the effects of extended defect formation and annealing on enhanced diffusion into a multizone, semiempirical model. The multizone model divides the implant profile into three zones defining regions of different defects and diffusion enhancements. The model also contains the initial enhanced diffusion and the transient diffusion effects associated with the dissolution of defect clusters and the annealing of extended defects, respectively. The saturation time for transient-enhanced diffusion contains an exponential function of implant dose in order to model the increase in point defect generated with higher implant dose. As a result, the model accurately simulates the boron diffusion profile over a wide range of implant doses and also shows the immobile boron peak of precipitated dopants produced during high dose ...

364

Development of the Weapon Borne Sensor parachute system  

Energy Technology Data Exchange (ETDEWEB)

A parachute system was designed and prototypes built to deploy a telemetry package behind an earth-penetrating weapon just before impact. The parachute was designed to slow the 10 lb. telemetry package and wire connecting it to the penetrator to 50 fps before impact occurred. The parachute system was designed to utilize a 1.3-ft-dia cross pilot parachute and a 10.8-ft-dia main parachute. A computer code normally used to model the deployment of suspension lines from a packed parachute system was modified to model the deployment of wire from the weapon forebody. Results of the design calculations are presented. Two flight tests of the WBS were conducted, but initiation of parachute deployment did not occur in either of the tests due to difficulties with other components. Thus, the trajectory calculations could not be verified with data. Draft drawings of the major components of the parachute system are presented.

1998-06-01

365

Development of new CAD system for steel structures of nuclear power plants  

Energy Technology Data Exchange (ETDEWEB)

IHI has developed a new Three-Dimensional Computer-Aided Design (3D-CAD) system to improve the design efficiency and quality of the steel structure of nuclear power plants. This system covers every design phase from the initial arrangement of structure to the production design sharing the same database. The system incorporates the design rules and professional expertise of designers, and enable easy and efficient design. The system can easily generate the three-dimensional data for structures, model data for stress analyses and composite arrangement data. The system has already been applied to several plants under construction and has achieved excellent results. The outline of the new CAD system is introduced. (author)

1999-09-01

366

Development of a computerized portal verification scheme for pelvic treatment fields  

International Nuclear Information System (INIS)

Purpose/Objective: At present, treatment verification between portal and reference images is performed based on manually-identified features by radiation oncologist, which is both time-consuming and potentially error-prone. There is a demand for the computerized verification procedure in clinical application. The purpose of this study is to develop a computerized portal verification scheme for pelvic treatment fields. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature matching between reference and portal images and quantitative evaluation of patient setup. Electronic portal images with a matrix size of 256 x 256 and 12 bit gray levels were acquired using a liquid matrix electronic portal imaging device. Simulation images were acquired by digitizing simulation films using a TV camera into images with 256 x 256 matrix and 8 bit gray levels. Initially a Canny edge detector is applied to identify the ...

1996-09-01

367

Determination of two-phase natural circulation interfacial parameters by real-time neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena between the liquid and the gas.

2003-07-01

368

Determination of two-phase natural circulation interfacial parameters by real-time neutron radiography  

International Nuclear Information System (INIS)

Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena between the liquid and the gas.

2003-10-05

369

Control area performance improvement by extended security constrained economic dispatch  

Energy Technology Data Exchange (ETDEWEB)

An algorithm for solving the extended security constrained economic dispatch (ESCED) problem with real-time economic dispatch grade speed and reliability is presented. The ESCED problem is formulated by adding regulating margin and ramp rate constraints to the network security constrained economic dispatch problem previously solved by the CEDC algorithm. Starting with Newton`s method to optimize the Lagrangian, the ESCED is developed by superimposing on Newton`s method eight major components called Tracking Start Initialization, Hessian Pre-Elimination, Implicit Dual Variable Calculations, Regulating Margin Sensitivity Coefficient Calculations, Traumatic Event Evaluation, Constraint Relaxation, Implicit Ramp Rate Constraint Implementation, and Relaxed Incremental Cost Calculations. Test results are also presented.

1997-02-01

370

Contribution of several mechanisms to the alpha particle elastic scattering in the angle range near 180 deg  

International Nuclear Information System (INIS)

The contribution of exchange processes (heavy stripping and substitution) into the amplitude of the 25-30 MeV #alpha#-particle elastic scattering by "1"2C and "4"0Ca nuclei is examined taking into account the distortion of plane waves of initial and finite particles. The eikonal approximation is used for accounting for distortions. The matrix elements of exchange processes are calculated. The results of calculations show that the Wronskian cutoff radii are close to those which have been obtained for calculation of exchange processes in the plane-wave approximation. The moduli of the values defining the contribution of exchange processes to the total S matrix are plotted. Also presented are Argand diagrams and angular distributions for both reactions. It has been established that the account for exchange processes improves the agreement of theoretical curves with the experiment in the whole range of angles, as compared with the optical model.

371

Continuum theory of axial segregation in a long rotating drum  

Energy Technology Data Exchange (ETDEWEB)

We develop a continuum description for the axial segregation of granular materials in a long rotating drum based on the dynamics of the thin near-surface granular flow coupled to bulk flow. The equations of motion are reduced to the one-dimensional system for two local variables only, the concentration difference and the dynamic angle of repose, or the average slope of the free surface. The parameters of the system are established from comparison with experimental data. The resulting system describes both initial transient traveling wave dynamics and the formation of quasi-stationary bands of segregated materials. A long-term evolution proceeds through slow logarithmic coarsening of the band structure which is analogous to the spinoidal decomposition described by the Cahn-Hilliard equation. {copyright} {ital 1999} {ital The American Physical Society}

1999-08-01

372

Continuum theory of axial segregation in a long rotating drum  

International Nuclear Information System (INIS)

We develop a continuum description for the axial segregation of granular materials in a long rotating drum based on the dynamics of the thin near-surface granular flow coupled to bulk flow. The equations of motion are reduced to the one-dimensional system for two local variables only, the concentration difference and the dynamic angle of repose, or the average slope of the free surface. The parameters of the system are established from comparison with experimental data. The resulting system describes both initial transient traveling wave dynamics and the formation of quasi-stationary bands of segregated materials. A long-term evolution proceeds through slow logarithmic coarsening of the band structure which is analogous to the spinoidal decomposition described by the Cahn-Hilliard equation. copyright 1999 The American Physical Society

1999-08-01

373

Continuous emission monitoring and quality assurance requirements for new power plants  

International Nuclear Information System (INIS)

Electric utility plants, for which construction commenced after September 18, 1978, must install and operate continuous emission monitoring (CEM) systems to demonstrate compliance with SO_2 and NO_x emission standards. Furthermore, effective December 4, 1987, each plant must develop and implement a CEM quality assurance (QA) program. This paper reviews the CEM and QA requirements set forth by new source performance standards (NSPS) promulgated by the Environmental Protection Agency. The paper summarizes operating characteristics of the 32 power plants currently subject to NSPS and describes the types of CEM systems used by these plants. Also, to the extent available, the paper presents the results of initial (i.e., first quarter 1988) QA activities (e.g., audits and calibration drift assessments) conducted by these plants.

1988-09-25

374

Computed tomography of the acetabular fractures  

Energy Technology Data Exchange (ETDEWEB)

In a retrospective study of 21 patients, in whom the acetabular fractures were suspected on initial radiographs, we compared and analysed the computed tomographic findings and plain radiographic findings. The results were as follow: 1. In patients with multiple trauma, no further change in position was required during CT examinations. 2. CT showed intraarticular loose bodies, which were invisible on plain radiographs. 3. CT was useful in detecting the fractures of acetabular rims, medial wall of acetabulum, and femoral head. 4. CT permitted better evaluation of shape, extent, and degree of separation of fracture fragments. 5. CT was helpful in detecting the associated fractures and soft tissue injuries. 6. CT also demonstrated the adequacy of reduction, the position of metallic fixation devices, and the presence or absence of remaining intraarticular osseous fragments after surgery.

1986-04-15

375

Compression molded energy storage flywheels  

Energy Technology Data Exchange (ETDEWEB)

Flywheels containing fiber-reinforced composite materials have attributes suitable for vehicular propulsion, indicating the need for rotor designs which are easily manufactured and low in cost. This development goal was pursued in a cooperative effort between Owens-Corning Fiberglas and Lawrence Livermore Laboratory which investigated flywheels made from compression-molded sheet molding compound (SMC). The design resulted from a Lawrence Livermore analysis, with successful fabrication achieved using a procedure developed by Owens-Corning. Details concerning materials selection, rotor fabrication, and testing are discussed. Owens-Corning subsequently initiated a technical/marketing survey to determine current industrial interests in a low-cost flywheel design; precursory information, pertaining to composite flywheels in particular, is described.

1982-08-01

376

Combining innovative technology demonstrations with dense nonaqueous phase liquids cleanup  

Energy Technology Data Exchange (ETDEWEB)

Radioactively contaminated acidic aqueous wastes and organic liquids were discharged to the soil column at three disposal sites within the 200 West Area of the Hanford Site, Washington. As a result, a portion of the underlying groundwater is contaminated with carbon tetrachloride several orders of magnitude above the maximum contaminant level accepted for a drinking water supply. Treatability testing and cleanup actions have been initiated to remove the contamination from both the unsaturated soils to minimize further groundwater contamination and the groundwater itself. To expedite cleanup, innovative technologies for (1) drilling, (2) site characterization, (3) monitoring, (4) well field development, and (5) contaminant treatment are being demonstrated and subsequently used where possible to improve the rates and cost savings associated with the removal of carbon tetrachloride from the soils and groundwater.

1993-05-01

377

Collisional Cooling of Negative Ion Beams  

Science.gov (United States)

Investigations have been conducted to determine the feasibility of using collisional cooling for reducing the energy spreads and, consequently, the emittances of negative-ion beams. We have designed a gas-filled RF-quadrupole ion cooler equipped with provisions for retarding energetic negative ion beams to energies below thresholds for electron detachment at injection and for re-acceleration to high energies after the cooling process. The device has been used to cool O{sup -} and F{sup -} ion beams with initial energy spreads, {Delta}E > 10 eV to final energy spreads, {Delta}E {approx} 2 eV FWHM. Overall transmission efficiencies of {approx}14% for F{sup -} beams have been obtained. Experimental results show that electron detachment is the major loss mechanism for negative ions.

2001-06-29

378

Collisional Cooling of Negative Ion Beams  

Energy Technology Data Exchange (ETDEWEB)

Investigations have been conducted to determine the feasibility of using collisional cooling for reducing the energy spreads and, consequently, the emittances of negative-ion beams. We have designed a gas-filled RF-quadrupole ion cooler equipped with provisions for retarding energetic negative ion beams to energies below thresholds for electron detachment at injection and for re-acceleration to high energies after the cooling process. The device has been used to cool O{sup -} and F{sup -} ion beams with initial energy spreads, {Delta}E > 10 eV to final energy spreads, {Delta}E {approx} 2 eV FWHM. Overall transmission efficiencies of {approx}14% for F{sup -} beams have been obtained. Experimental results show that electron detachment is the major loss mechanism for negative ions.

2001-06-29

379

Clinical Evaluation of the Zilver Vascular Stent for Symptomatic Iliac Artery Disease  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate the safety and effectiveness of the Zilver vascular stent in the treatment of de novo or restenotic lesions in the external and common iliac arteries.Materials and MethodsRegardless of the results of an initial percutaneous transluminal angioplasty (PTA), 151 consecutive patients were implanted with Zilver vascular stents (Cook, Bloomington, Ind) in up to two stenotic (?10 cm) or occluded (?5 cm) atherosclerotic lesions of the external or common iliac arteries. The primary endpoint was the rate of major adverse events within 9 months after the procedure. Major adverse events were defined as death, myocardial infarction, target lesion revascularization, and limb loss. Secondary endpoints included acute procedural success, 30-day clinical success, 9-month pat...

2008-01-01

380

Cavitation erosion of advanced ceramics in water  

Energy Technology Data Exchange (ETDEWEB)

The performance of advanced ceramics under cavitation loading in distilled water was studied by using a laboratory test with vibration-induced cavitation following the pattern of the ASTM standard G32-92. The hardened and tempered martensitic steel 100Cr6 was used as a reference. The aim was to identify mechanisms and the effects of important microstructural parameters on damage of polished Al{sub 2}O{sub 3}, Al{sub 2}O{sub 3}-ZrO{sub 2}, ZrO{sub 2} and SiC ceramics. Results showed that surface damage of brittle ceramics was mainly dominated by intergranular fracture, followed by detachment of single grains or fragments of them. Both incubation time and erosion rate were affected by the amount of initial surface cavities, grain sizes and secondary phases at grain boundaries. (orig.)

2006-10-15

381

Black hole radiation in Bose-Einstein condensates  

CERN Document Server

We study the phonon fluxes emitted when the condensate velocity crosses the speed of sound, i.e., in backgrounds which are analogue to that of a black hole. We focus on elongated one dimensional condensates, and on stationary flows. Our theoretical analysis and numerical results are based on the Bogoliubov-de-Gennes equation without any further approximation. The spectral properties of the fluxes and of the long distance density-density correlations are obtained, with and without an initial temperature. In realistic conditions, we show that the condensate temperature dominates the fluxes, and thus hides the presence of the spontaneous emission (the Hawking effect). We also explain why the temperature amplifies the long distance correlations which are intrinsic to this effect. This confirms that the correlations pattern offers a neat signature of the Hawking effect. Optimal conditions to observe the pattern are discussed.

2009-01-01

382

Assessment and control of fetal exposure  

Energy Technology Data Exchange (ETDEWEB)

The assessment and control of fetal exposure to radiation in the workplace is an issue that is complicated by both biological and political/social ramifications. As a result of the dramatic increase in the number of women employed as radiation workers during the past 10 years, many facilities using radioactive materials have instituted fetal protection programs with special requirements for female radiation workers. It is necessary, however, to ensure that any fetal protection program be developed in such a way as to be nondiscriminatory. A study has been initiated whose purpose is to balance the political/social and the biological ramifications associated with occupational protection of the developing embryo/fetus. Several considerations are involved in properly balancing these factors. These considerations include appropriate methods of declaring the pregnancy, training workers, controlling the dose to the embryo/fetus, measuring and ...

1991-10-01

383

Applications of magnetorheological brakes in manual control of lifting devices and manipulators  

International Nuclear Information System (INIS)

The article is aimed to design and testing of joystick with force feedback used in direct, human control of lifting device. The paper starts with the basic description of designed and tested by us MR rotary brake. Some initial laboratory investigations results of such brakes are presented. The usage of MR brakes in 2 axis joystick is proposed. Such, built by as joystick, is described. It was used as Human-Machine Interface in active control of lifting device. The designed and built 2 axis manipulator with electrohydraulic drive is described. In the paper, the based on PC with input/output card, control system of mentioned above joystick with MR brake and manipulator is described. Finally the control algorithm is proposed.

2009-02-01

384

Application of electrochemically dissolved iron in the removal of tannic acid from water  

British Library Electronic Table of Contents (United Kingdom)

Effects of some experimental parameters (supporting electrolyte, initial pH and current density) on the performance of electrocoagulation process using iron electrodes were investigated. Results of experiments showed that dissolution of iron is purely electrochemical and fits well with Faraday's law and leads to Fe^2^+ which are chemically oxidized into Fe^3^+ in aerated conditions. In neutral and alkaline conditions, the reaction between hydroxyl ions generated at the cathode and dissolved iron ions forms insoluble hydroxo-iron species. Potentiodynamic polarization tests showed that the formation of passive film on iron anode limits the continuous electrochemical dissolution of iron. Corrosion and pitting potentials largely depend on the nature of supporting electrolyte. The dissolution o...

2011-01-01

385

Analysis of thermoluminescence glow curves of minerals sphene and epidote for radiation damage studies  

Energy Technology Data Exchange (ETDEWEB)

Thermoluminescence (TL) properties of sphene and epidote are of interest in studies related to their radiation damage. Natural and artificially induced TL of these minerals has, therefore, been investigated. Both minerals exhibit complex glow curves with several overlapping peaks. The Tsub(m) -Tsub(STOP) thermal cleaning procedure has revealed three peaks in the ..gamma.. ray induced glow curve of each mineral. That these peaks obey second order kinetics was indicated by the continuously slanting structure of the Tsub(m)-Tsub(STOP) curve. The TL parameters E and s have been calculated using (i) the initial rise method, and (ii) the glow-peak shape method. In general, the values of E calculated by the first method are found to be higher than those from the second. The TL curve-fitting method is also applied in order to calculate these parameters and to serve as a cross-check on the results.

1986-01-01

386

Analysis of the dynamics of coal char combustion with ignition and extinction phenomena: Shrinking core model  

Energy Technology Data Exchange (ETDEWEB)

Single-particle combustion of coal char is analyzed using a generalized shrinking core model. Finite volume method, which was earlier employed by the authors in solving moving boundary problems involving fluid-solid noncatalytic reactions in general, is used to solve fully transient mass and energy equations. The model takes into account convection and diffusion inside the particle as well as in the boundary layer. The computed results are compared with the experimental data of the authors for combustion of coal char in a fluidized bed combustor. The effects of parameters such as bulk temperature and initial particle radius on the combustion dynamics are examined. The phenomena of ignition and extinction are also investigated. Finally, the importance of Stefan flow, originating due to nonequimolar counterdiffusion, on combustion of coal char is analyzed.

2008-09-15

387

Alpha-induced reactions in iridium  

Energy Technology Data Exchange (ETDEWEB)

The excitation function of ({alpha},{ital xn}) reactions on {sup 191}Ir (abundance 37.3%) and on {sup 193}Ir (abundance 62.7%) has been measured for the 17--55 MeV alpha-particle bombarding energy range. The stacked foil activation technique and {gamma}-ray spectroscopy were used to determine the cross sections. The experimental data were compared with calculated values obtained by means of a geometry-dependent hybrid model. The initial exciton number {ital n}{sub 0}=4 with {ital n}=2, {ital p}=2, and {ital h}=0 gives the best agreements with the presently measured results. To calculate the excitation function theoretically a computer code was used. This set of excitation functions provides a data basis for probing the validity of combined equilibrium and preequilibrium reaction models in a considerable energy range.

1992-05-01

388

Adsorption of hexavalent chromium from aqueous solution by using activated red mud  

Energy Technology Data Exchange (ETDEWEB)

Adsorption by activated red mud (ARM) is investigated as a possible alternative to the conventional methods of Cr(VI) removal from aqueous synthetic solutions and industrial effluents. Adsorption characteristics suggest the heterogenous nature of the adsorbent surface sites with respect to the energy of adsorption. Various factors such as pH, contact time, Cr(VI) concentration, amount of adsorbent, and temperature are taken into account, and promising results are obtained. The applicability of the Langmuir as well as Freundlich adsorption isotherms for the present system is tested. The loading factor (i.e., milligrams Cr(VI) adsorbed per gram of ARM) increased with initial Cr(VI) concentration, whereas a negative trend was observed with increasing temperature. The influence of the addition of anions on the adsorption of Cr(VI) depends on the relative affinity of the anions for the surface and the relative concentrations of the anions.

1999-09-01

389

Accelerated aging of catalytically airblown asphalt membranes under simulated uranium mill tailings impoundment conditions  

International Nuclear Information System (INIS)

This paper evaluates the performance of asphalt membranes by examining the chemical and permeability changes experienced by the asphalt during aging tests. The aging process was accelerated by exposing the asphalt to elevated temperatures, high oxygen concentrations, and increased strengths of aqueous oxidizing agents. The synergistic effects of the variables are evaluated by using a fractional factorial experimental design. The installation costs for a catalytically airblown asphalt liner are roughly half that of the typical polymeric materials, and also less than the rubberized asphalt membrane. The results of the initial accelerated aging tests of the asphalt membranes indicate that this material will provide stable, long-term leachate isolation in a mill tailings environment.

1982-12-01

390

A phenomenological model for the macroscopic characteristics of irradiated silicon  

International Nuclear Information System (INIS)

The dependence of the carrier concentrations, of the resistivity and of the Hall coefficient of irradiated silicon on the neutron fluences has been investigated, starting from the supposition that the main phenomena induced by irradiation in the semiconductor bulk are shallow-donor removal and deep-centres creation. The free parameters of the model are initial doping of the starting material, the permitted energy level values of the radiation-induced centres in the semiconductor band gap and their introduction rates. The influence of each parameter on the calculated dependences is studied in detail, for three cases: one deep acceptor-like centre, two deep acceptors and one deep acceptor plus one deep donor-like centre. each of the three cases is discussed in correspondence with different experimental results.

391

A partnership approach to service needs assessment with family caregivers of an aging relative living at home: A qualitative analysis of the experiences of caregivers and practitioners  

British Library Electronic Table of Contents (United Kingdom)

Background: As the global population ages, support for family caregivers who provide the bulk of care to community-dwelling older people is becoming ever more important. However, in many countries, homecare-service practitioners currently do not follow a systematic approach to assessing and responding to caregiver needs. Objectives: The aim of this study was to explore the experiences of caregivers and practitioners who took part in a field test of the Family Caregivers Support Agreement (FCSA) tool, a modified version of the Carers Outcome Agreement Tool (COAT) initially developed as the result of an Anglo-Swedish study. Both the COAT and the FCSA are designed to facilitate partnerships between caregivers and practitioners so that needs assessment and subsequent support services are negot...

2010-01-01

392

2D SPH simulations of a single planet migration in a protoplanetary disc  

Science.gov (United States)

Migration of protoplanets inside an accretion disc of a forming star is the most probable scenario for planetary system formation according to current models. Unsolved problems exist, concerning migration times and mechanisms. We report here the results of a 2D hydrodynamic study within an SPH scheme, analysing migration of an Earth-like or a Jupiter-like planet inside an inviscid sub-Keplerian accretion disc, as a function of the initial specific angular momentum of the infalling accretion disc matter. Particle capture by the protoplanet causes a rapid migration, within a few orbits, for the Earth like planet, and about 104 orbits for the Jupiter like planets. The effect of a planet pseudo-atmosphere is also discussed.

2010-01-01

393

2010 power generation sector restructuring in Romania-A critical assessment  

International Nuclear Information System (INIS)

In the spring of 2009, the Romanian government has proposed a restructuring of the national power generation sector segment that is still owned by the state. As most of the power generation capacity is still state-owned, this restructuring will dramatically alter the competitive landscape of this sector. This paper is analyzing the rationale and principles of the restructuring as stated by government documents and officials, the assessment methodology and criteria proposed by the government, as well as the proposed final outcome of the restructuring initiative. Based on this critical assessment and the early results of the restructuring's implementation, we are able to make recommendations that can be considered for a revised restructuring approach. - Research highlights: #-># Power generation sector restructuring is proposed in 2009 by the Romanian government. #-># We assess the objectives, methodology and proposed outcome of the ...

2011-03-01

394

Relation between frequency of seismic wave and resolution of tomography; Danseiha tomography kaiseki ni okeru shuhasu to bunkaino no kankei  

Energy Technology Data Exchange (ETDEWEB)

With regard to the elastic wave exploration, discussions have been given on the relationship between frequency and resolution in P-wave velocity tomography using the initial travel time. The discussions were carried out by using a new analysis method which incorporates the concept of Fresnel volume into tomography analysis. The following two arrangements were used in the calculation: a cross hole arrangement, in which seismic source and vibration receiving points were arranged so as to surround the three directions of a region extending 250 m in the horizontal direction and 500 m in the vertical direction, and observation is performed between two wells, and a permeation VSP arrangement in which the seismic source is installed on the ground surface and receiving points installed in wells. Restructuring was performed on the velocity structure by using a total of 819 observation travel times. This method has derived results of the restructuring ...

1997-05-27

395

Optimization of Valve Disc Using Orthogonal Array and Kriging Model  

Science.gov (United States)

A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing. Currently, FEA is often used to predict the safety in the design of valve disc. Also, the study about the affection of butterfly valve's disc to the valve flow characteristics by using CFD has been done by many researchers. Along with the development of computer technique, design and analysis of computer experiments has becoming more and more important in engineering design and optimization. Hereinto Kriging model is one popular analysis approach for the purpose of creating a cheap ``meta-model'' as a surrogate to a computationally expensive simulation model. In this paper, the numerical analysis considered the strength, pressure loss coefficient and weight of valve disc simultaneously is investigated to improve the shape of a traditional butterfly valve disc. Firstly, an initial model of butterfly valve is made to evaluate the performance of the valve disc by using CFD ...

2008-10-01

396

Numerical heat transfer studies of PCMs used in a box-type solar cooker  

Energy Technology Data Exchange (ETDEWEB)

Theoretical investigations on the phase change materials (PCMs) used as the heat storage media for box-type solar cookers have been conducted in this study. The selected PCMs are magnesium nitrate hexahydrate, stearic acid, acetamide, acetanilide and erythritol. For a two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Different materials such as glass, stainless steel, tin, aluminum mixed, aluminum and copper are used as the heat exchanger container materials in the numerical calculations. The large value of thermal conductivity of heat exchanger container material did not make a significant contribution on the melt fraction except for at very low thermal conductivities. Based on the theoretical results, stearic acid and acetamide are found to be good compatibility with latent heat storage system. It is also found that the initial temperature of PCM does not ...

2008-05-15

397

Monte-Carlo-based simulation of LWR cores with innovative fuel concepts  

International Nuclear Information System (INIS)

High resolution Monte-Carlo simulations show that the neutron spectrum, fuel burnup and fuel temperature feedback effect of a PWR core loaded with Thoria-based fuel (Th/Pu-O_2) do not significantly differ from the MOX fuelled one due to the similar neutronic characteristics of both fertile materials (Th-232, U-238). The core physics of this fuel variant is characterized by an enhanced moderator/void temperature coefficient (by factor 2.4) and high incineration rate for Pu (approx. 60 %). A PWR core loaded with the Molybdenum-based inert matrix fuel (IMF) - in contrast to MOX-, shows a harder spectrum, resulting in small temperature coefficients of reactivity and particularly in a higher fuel depletion rate as well as an enhanced TRU reduction performance. The incineration of Pu amounts to 46 % resulting, in turn, in generation of minor actinides of about 10 % of the total Pu consumption. The higher excess reactivity ...

2009-05-03

398

Graphite electrode arc melter demonstration Phase 2 test results  

Energy Technology Data Exchange (ETDEWEB)

Several U.S. Department of Energy organizations and the U.S. Bureau of Mines have been collaboratively conducting mixed waste treatment process demonstration testing on the near full-scale graphite electrode submerged arc melter system at the Bureau`s Albany (Oregon) Research Center. An initial test series successfully demonstrated arc melter capability for treating surrogate incinerator ash of buried mixed wastes with soil. The conceptual treatment process for that test series assumed that buried waste would be retrieved and incinerated, and that the incinerator ash would be vitrified in an arc melter. This report presents results from a recently completed second series of tests, undertaken to determine the ability of the arc melter system to stably process a wide range of {open_quotes}as-received{close_quotes} heterogeneous solid mixed wastes containing high levels of organics, representative of the wastes buried and stored at the Idaho ...

1996-06-01

399

Evaluation of measuring data of small photovoltaic power systems within the framework of the German Federal-State 1000 Roofs PV programme. Final report; 1000-Daecher Mess- und Auswerteprogramm. Auswertung der Messdaten von photovoltaischen Kleinanlagen im Rahmen des Bund-Laender-1000 Daecher-Photovoltaik-Programms. Wissenschaftlicher Endbericht  

Energy Technology Data Exchange (ETDEWEB)

Within the framework of the German Federal-State 1000 Roofs Photovoltaic Programme monthly measuring data and verbal comments on the PV system operation (reports on failures and defects) have been collected, stored in a databank and evaluated for the period 1991 to 1997 for a differing number of PV systems. In addition to this came along data of initially 100, then 40 intensively measured systems. The results of the measuring data evaluation as well as the results of further accompanying research projects to the Federal-State 1000 Roofs Photovoltaic Programme (e.g. low energy yield analysis, on-site inspections and measuring of nominal powers) are summarised. Starting from the gained results, conclusions and recommendations are given for the design, installation and operation for future grid-connected PV-systems. Also it is pointed to the remaining need for optimisation and R and D. Additional part of ...

1998-10-16

400

Contribution to the study of sputtering and damage of uranium dioxide by fast heavy ions; Contribution a l'etude de la pulverisation et de l'endommagement du dioxyde d'uranium par les ions lourds rapides  

Energy Technology Data Exchange (ETDEWEB)

Swift heavy ion-solid interaction leads in volume to track creation and on the surface to the ejection of particles into the vacuum. To learn more about initial mechanisms of track formation, we are focused on the sputtering of uranium dioxide by fast heavy ions. This present study is exclusively devoted to the influence of the electronic stopping power on the emission of neutral particles and especially on their angular distribution. These measurements are completed by those of the ions emitted from UO{sub 2} targets bombarded with swift heavy ions. The whole experimental results give access to: i) the nature of the sputtered particles; ii) the charge state of the emitted particles; iii) the direction of ejection of the sputtered particles ; iv) the sputtering yields deduced from the angular distributions. These results are compared to the prediction of the sputtering models proposed in the literature and it seems that the ...

2001-03-01

401

Characterization of iron nitrides prepared by spark erosion, plasma nitriding, and plasma immersion ion implantation  

Energy Technology Data Exchange (ETDEWEB)

The effect of the nitrogen uptake in {alpha}-iron upon spark erosion in gaseous and liquid ammonia, plasma nitriding, and plasma immersion ion implantation is studied. The resulting phases and hyperfine parameters, measured by the Moessbauer spectroscopy, are discussed from the point of view of initial conditions of their preparation and subsequent heat and/or mechanical treatment. Spark erosion in the ammonia gas produces fine particles with the dominating ferromagnetic {alpha}-Fe phase (50%). The 20% of specimen volume form {alpha}'-Fe and {alpha}''-Fe{sub 16}N{sub 2} phases. The last 30% occupy the {gamma}'-Fe{sub 4}N, ferro- and paramagnetic {epsilon} phases, and {gamma}-Fe(N). Nitriding in the liquid ammonia allows to incorporate the higher content of nitrogen into {alpha}-iron particles which results in the formation of paramagnetic {epsilon}({zeta})-Fe{sub 2}N phase. This phase ...

2001-09-01

402

Characterization of iron nitrides prepared by spark erosion, plasma nitriding, and plasma immersion ion implantation  

International Nuclear Information System (INIS)

The effect of the nitrogen uptake in #alpha#-iron upon spark erosion in gaseous and liquid ammonia, plasma nitriding, and plasma immersion ion implantation is studied. The resulting phases and hyperfine parameters, measured by the Moessbauer spectroscopy, are discussed from the point of view of initial conditions of their preparation and subsequent heat and/or mechanical treatment. Spark erosion in the ammonia gas produces fine particles with the dominating ferromagnetic #alpha#-Fe phase (50%). The 20% of specimen volume form #alpha#'-Fe and #alpha#''-Fe_1_6N_2 phases. The last 30% occupy the #gamma#'-Fe_4N, ferro- and paramagnetic #epsilon# phases, and #gamma#-Fe(N). Nitriding in the liquid ammonia allows to incorporate the higher content of nitrogen into #alpha#-iron particles which results in the formation of paramagnetic #epsilon#(#zeta#)-Fe_2N phase. This phase also dominates the surface of #alpha#-iron specimen ...

2001-09-01

403

Assessment of vesical-ureteral reflux in transplant patients using radionuclide cystography; Exploration scintigraphique des reflux vesico-renaux chez les patients transplantes renaux  

Energy Technology Data Exchange (ETDEWEB)

Direct radionuclide cystography is known to be sensitive and safe in children with suspected vesical-ureteral reflux. In this study we have investigated the utility of direct radionuclide cystography in renal transplant recipients with a recent history of pyelonephritis or recurrent urinary infections. Direct radionuclide cystography is a simple test, however it requires a rigorous methodology in order to obtain images during fill-in as well as during voiding in both men and women. The images must be interpreted using a rigorous image display methodology. Twenty-eight radionuclide cystographies were performed in 17 patients. Among the 17 tests performed for the initial diagnosis of reflux , 12 were positive. Four patients with positive results and four patients with negative results were also investigated by radiologic cystography. Similar results were obtained in those patients. Nine scintigraphies ...

1995-12-31

404

Accurate, stable, explicit, parabolized navier-stokes solver for high speed flows  

Energy Technology Data Exchange (ETDEWEB)

A stable, accurate, and efficient implementation of MacCormack's explicit algorithm for the Parabolized Navier-Stokes equations is demonstrated. The familiar problem of decoding the conservative axial flux vector is solved, resulting in accurate, smooth dependent variable profiles through the viscous-layer sonic line. Source terms due to transformation of the parabolized governing equations into the computational plane and the equations into the computational plane and the resulting metric differencing have been identified and eliminated through inclusion of appropriate geometric conservation law terms. Test cases computed include two- and three-dimensional supersonic and hypersonic flow at laminar and turbulent Reynolds numbers. The computed results demonstrate very good agreement with experiment and with solutions of the full Navier-Stokes equations. Computational times required for the MacCormack explicit PNS ...

1986-01-01

405

Accelerated stability test techniques for middle distillate fuels  

Energy Technology Data Exchange (ETDEWEB)

Improved test techniques are needed for evaluating the inherent stability of middle distillate fuels both in surveillance and in procurement activities. A project was initiated to define and evaluate the contributing conditions leading to the formation of deleterious products in accelerated aging tests of middle distillate fuels and to relate these results to an experimental definition of more repeatable/reliable middle distillate fuel stability test technique(s). A literature search was conducted to provide a list of stability test techniques and their interpretations which could be used in a correlative middle distillate fuel stability test program. For this program, seven accelerated stability tests were chosen and evaluated using a set of six test fuels. The test techniques were selected to represent a wide variety of test conditions, including temperature, aging time, and oxygen availability. These six test fuels were purposely chosen to ...

1981-01-01

406

A personal computer based system to evaluate J-integral by a single specimen unloading compliance method: Pt. 2  

International Nuclear Information System (INIS)

A personal computer based single specimen unloading technique has been demonstrated using a nuclear grade pressure vessel material, A533B Class I steel, and an #alpha#-#beta# titanium alloy, CORONA-5. Experimental parameters investigated in the case of steel include the effect of test temperature, loading rate and neutron irradiation. Results revealed the effect of dynamic strain aging (DSA) as a drop in the critical crack initiation fracture toughness (Jsub(q)); the minimum in Jsub(q) shifts to higher temperatures at higher test speeds as predicted from DSA models. In CORONA-5, the effects of microstructure and heat treatment for two different sizes of equiaxed #alpha# morphology in a #beta#-matrix heat treated to different yield strengths were investigated. It is found that the observed higher values of Jsub(q) and tearing modulus result from a greater tortuosity of the crack path and ease of crack blunting. The largest ...

407

Therapeutic Approaches to the Treatment of Botulism  

Science.gov (United States)

... above. In the initial round of experiments, the venom of Dendroaspis augustepsis was tested for its actions on neuromuscular transmission. ...

1989-10-01

408

Symposium (International) (4th) on DETONATION Held at ...  

Science.gov (United States)

... 442 RHF Stresau CONFINEMENT EFFECTS IN EXPLODING BRIDGEWIRE INITIATION OF DETONATION ..... ...

1965-10-15

410

Mechanisms of EBW HE initiation  

Science.gov (United States)

Exploding bridgewire (EBW) initiation of high explosives (HE) has been used for many years without a clear understanding of the mechanisms involved. Evidence indicates that the shock pressures produced by the EBW may be insufficient for direct initiation and that the electric field about the wire at the time of burst ionizes the surface of the HE. We hypothesize that the ionization pre-sensitizes the HE so that a weak shock can then initiate a detonation wave. 13 refs., 7 figs.

1991-05-15

411

Means for the Elimination of a Cartridge Rim.  

Science.gov (United States)

... Descriptors : *Combustible cartridge cases, *Patents, Cartridge cases, Explosive trains, Explosives initiators, Consumption. ...

1975-12-30

412

Insensitive fuze train for high explosives  

Energy Technology Data Exchange (ETDEWEB)

A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124.

1994-01-01

416

A Report on the Evaluation of the NSF's Informal Science Education (ISE) Program  

Science.gov (United States)

... science in places outside of schools, with materials and activities initially not developed for ...

417

Prediction of response of blood lead to airborne and dietary lead from volunteer experiments with lead isotopes  

Energy Technology Data Exchange (ETDEWEB)

To predict the response of blood lead to airborne and dietary lead requires knowledge of the rate of uptake of lead into the body from lung and gut, its subsequent partitioning between compartments, the stay time in those compartments, and its redistribution or excretion. Tracer studies with volunteers have shown no differences in systemic distribution of inorganic lead between tissues whether it is taken by inhalation, ingestion or injection. Lead is rapidly transferred from plasma to red cells, and there is slower movement thence into liver and other soft tissues, to bone, and to excreta. Work at Harwell and elsewhere with /sup 203/Pb has shown that the initial rapid distribution leaves rather over half the assimilated lead attached to red cells. The result is remarkably consistent, and applies also to dogs and baboons. The renal clearance (Vu) (ratio of U to CB, or daily urinary output expressed as mass of blood having the same lead ...

1985-04-22

418

The Preliminary GAMMA Code Thermal hydraulic Analysis for the Steady State of HTR-10 Initial Core  

Energy Technology Data Exchange (ETDEWEB)

This report describes the preliminary thermalhydraulic analysis of HTR-10 steady state full power initial core to provide a benchmark calculation of VHTGR(Very High-Temperature Gas-Cooled Reactors) safety analysis code of GAMMA(GAs Multicomponent Mixture Analysis). The input data of GAMMA code are produced for the models of fluid block, wall block, radiation heat transfer and each component material properties in HTR-10 reactor. The temperature and flow distributions of HTR-10 steady state 10 MW{sub th} full power initial core are calculated by GAMMA code with boundary conditions of total reactor inlet flow rate of 4.32 kg/s, inlet temperature of 250 .deg. C, inlet pressure of 3 MPa, outlet pressure of 2.992 MPa and the fixed temperature at RCCS water cooling tube of 50 .deg C. The calculation results are compared with the measured solid material temperatures at 22 fixed instrumentation positions in HTR-10. The wall ...

2006-07-15

419

Virostatic potential of micro-nano filopodia-like ZnO structures against herpes simplex virus-1.  

Science.gov (United States)

Herpes simplex virus type-1 (HSV-1) entry into target cell is initiated by the ionic interactions between positively charged viral envelop glycoproteins and a negatively charged cell surface heparan sulfate (HS). This first step involves the induction of HS-rich filopodia-like structures on the cell surface that facilitate viral transport during cell entry. Targeting this initial first step in HSV-1 pathogenesis, we generated different zinc oxide (ZnO) micro-nano structures (MNSs) that were capped with multiple nanoscopic spikes mimicking cell induced filopodia. These MNSs were predicted to target the virus to compete for its binding to cellular HS through their partially negatively charged oxygen vacancies on their nanoscopic spikes, to affect viral entry and subsequent spread. Our results demonstrate that the partially negatively charged ZnO-MNSs efficiently trap the virions via a novel virostatic mechanism rendering them ...

2011-08-26

420

The corrosion behaviour of nanocrystalline PVD model steel films. Influence of structure and Molybdenum content; Das Korrosionsverhalten von nanokristallinen PVD-Modellstahlschichten. Einfluss der Struktur und des Molybdaen-Gehaltes  

Energy Technology Data Exchange (ETDEWEB)

By magnetron sputtering model steel films with specific properties can be prepared for purposive surveys. By changing the deposition parameters certain properties of these films can be influenced. For this thesis steel films with 18% Cr and 8% Ni have been prepared in order to study specific parameters on the corrosion resistance of bulk stainless steel. Chemical composition, microstructure, and surface morphology of these films have been characterized. In comparison to bulk steel sheets with the same chemical composition they have a smaller grain size and a ferritic structure. In contrast to bulk steel sheets they don`t contain any nonmetallic inclusions like Mn-sulfides. The influence of these structural differences on the corrosion resistance has been studied. For this purpose the electrochemical properties of the sputter-deposited steels have been compared with the properties of steel sheets with a similar chemical composition (DIN 1.4301, AISI 304) in neutral and acidic Cl{sup ...

1995-12-31

421

Safety-technical characteristics of biomass, coal and straw. Final report  

Energy Technology Data Exchange (ETDEWEB)

Safety-technical factors related to spontaneous ignition and dust explosions of biomasses were investigated. Parametres of dust explosions and effect of inertisation on the maximum pressure (pmax) and the maximum rate of pressure rise (Kstmax) were studied at elevated initial pressure (1-9 bar). The level of inertisation required to prevent dust explosions totally was determined at different initial pressures. The sensitivity of fuels to spontaneous ignition and the effect of pressure on the sensitivity to and temperature of spontaneous ignition were studied on a pressurised dynamic self-ignition equipment. The effect of inertisation on the self-ignition temperature and alternatives of preventing spontaneous ignition by effective inertisation in the pressure ranges of 1 and 25 bar were investigated. As an example of application, results obtained with the laboratory test equipment were extrapolated to bin sizes used in ...

1995-12-31

422

Quantitative descriptions of nonlinear gravitational galaxy clustering  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate nonlinear gravitational galaxy clustering, three different quantitative analyses were carried out: two-point correlation functions, {xi}(r); fractal dimensions, D{sub q}; and f(N) statistics. The relation between the exponent {gamma} of the correlation function ({xi}(r) {proportional to} r{sup -{gamma}}) and the fractal dimensions, D{sub q}, was derived with the help of the probability distribution function, f(N), for finding N galaxies within a volume V. The methods were applied to analyze the results of N-body simulations with power law initial density fluctuations ( {delta}{sub k} {sup 2} {proportional to} k{sup n}, n = 1, 0, -1 and -2). These analyses show that the exponent, {gamma}, of the power law {xi}(r) is approximately 2 in the nonlinear regime for models with n = 1 and 0. For models with n = -1 and -2, the correlation functions comprise two parts of the intermediate and small scales in the nonlinear regime. ...

1990-01-01

423

Peroxi-coagulation degradation of C.I. Basic Yellow 2 based on carbon-PTFE and carbon nanotube-PTFE electrodes as cathode  

International Nuclear Information System (INIS)

The electrochemical treatment of solutions containing C.I. Basic Yellow 2 (BY2) in aqueous solutions with carbon-PTFE (polytetrafluoroethylene) and carbon nanotube (CNT)-PTFE electrodes as cathode has been studied. The fabricated electrodes were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The amount of electrogenerated H2O2 on the surface of these electrodes was investigated, too. The results showed that the amount of H2O2 obtained with the CNT-PTFE electrode was nearly three times higher than that of carbon-PTFE electrode. The decolorization efficiency of BY2 in peroxi-coagulation process reached 62% and 96% in the first 10 min by carbon-PTFE and CNT-PTFE electrodes at 100 mA, respectively. The effect of operational parameters such as applied current, initial pH and initial dye concentration was studied in an attempt to reach higher decolorization efficiency. The degradation and ...

2009-11-01

424

Modeling pitting corrosion damage of high-level radioactive-waste containers, with emphasis on the stochastic approach  

Energy Technology Data Exchange (ETDEWEB)

Recent efforts to identify methods of modeling pitting corrosion damage of high-level radioactive-waste containers are described. The need to develop models that can provide information useful to higher level system performance assessment models is emphasized, and examples of how this could be accomplished are described. Work to date has focused upon physically-based phenomenological stochastic models of pit initiation and growth. These models may provide a way to distill information from mechanistic theories in a way that provides the necessary information to the less detailed performance assessment models. Monte Carlo implementations of the stochastic theory have resulted in simulations that are, at least qualitatively, consistent with a wide variety of experimental data. The effects of environment on pitting corrosion have been included in the model using a set of simple phenomenological equations relating the parameters of the stochastic ...

1993-01-01

425

Magnetobiostratigraphy of the continental Paleocene upper Coalspur and Paskapoo formations near Hinton, Alberta  

Energy Technology Data Exchange (ETDEWEB)

A chronology for Paleocene strata of the Hinton area of west-central Alberta was developed from the integration of a magnetostratigraphic and palynostratigraphic study of the upper Coalspur and middle to upper Paskapoo strata in the Coal Valley to Obed Mountain area. The study resulted in the compilation of a complete section of 1100 m of strata with a maximum sediment accumulation rate of 250 m/m.y. Four new informal biostratigraphic units were used to highlight stratigraphically useful bioevents not previously recognized in existing zonations. These strata range in age from magnetochron 29r to 24r and palynozones Wodehouseia spinata Zone, Aquilapollenites reticulatus Subzone through the Pistillipollenite mcgregorii Zone. The 3 intervals with the most rapid changes in the palynoflora were the earliest Paleocene; the transition from the early to middle Paleocene; and in the late Paleocene. Each coincides with critical times in basin development, notably the ...

2008-06-15

426

Irradiation with and without razoxane in the treatment of incompletely resected or inoperable recurrent rectal cancer. Results of a small randomized multicenter study  

Energy Technology Data Exchange (ETDEWEB)

Background and Purpose: In an earlier phase II study, irradiation together with razoxane was shown to improve local control in recurrent rectal cancer. Therefore, the Austrian Society of Radiooncology (OeGRO) initiated a randomized controlled trial in 1992 to compare this combined treatment versus radiation therapy alone. Patients and Methods: Between 1992 and 1999, 36 patients with localized recurrences of rectal cancer were randomized to receive radiotherapy without (group A) or with razoxane (group B). The prognostic variables of the two groups were similar except for a longer median latency period from initial surgery to local recurrence in group A. High-energy photons with daily fractions between 170 and 200 cGy were used. The median total radiation dose was 60 Gy in each group. The patients in group B received a median razoxane dose of 9.6 g (range, 5-12 g). Main outcome measures were local control, overall survival, and toxicity. ...

2007-07-15

427

Final report of the second dye-tracer test at the Chesnut Ridge Security Pits, Y-12 Plant, Oak Ridge, Tennessee  

Energy Technology Data Exchange (ETDEWEB)

Martin Marietta Energy Systems, Inc. (Energy Systems) manages a closed hazardous waste disposal unit, Chestnut Ridge Security Pits (CRSP), in the form of two trenches and several auger-holes, located on top of the eastern portion of Chestnut Ridge at the Department of Energy (DOE) Oak Ridge Y-12 Plant in Tennessee. The groundwater monitoring system for the unit presently consists of a network of upgradient and downgradient monitor wells. To investigate the discharge of groundwater to springs and streams, Energy Systems, through Geraghty and Miller, Inc., conducted an initial dye-tracer study during the driest part of 1990. The dye was detected at some of the monitoring sites, but verification was necessary due to the proximity of some sites to extraneous dye sources. Based on the results of the initial study, Energy Systems recommended to the Tennessee Department of Environment and Conservation (TDEC) in the 1990 ...

1992-11-01

428

Experimental studies of 4-inch pipe whip test under BWR LOCA conditions  

Energy Technology Data Exchange (ETDEWEB)

Pipe whip tests or jet discharge tests have been performed at the Japan Atomic Energy Research Institute, which simulate the instantaneous circumferential guillotine break of primary coolant piping in nuclear power plants. The present paper describes the results of the pipe whip tests using test pipes of 4 inch diameter, under the BWR LOCA conditions, which were performed from 1979 to 1981. The tests were carried out at an initial pressure of about 6.8 MPa and an initial temperature of about 285/sup 0/C. The test pipe was 114.3 mm (4 in) in diameter, 8.6 mm in thickness and 4500 mm in length. The four pipe whip restraints used in the tests were the U-bar type of 8 mm in diameter and frabricated from Type 304 stainless steel. The experimental parameters were the clearance (30, 50 and 100 mm) and the overhang length (250, 400, 550 and 1000 mm). The main purpose of these tests is to investigate the effects of the clearance and ...

1983-10-01

429

Estimation of a stress field in the earth`s crust using drilling-induced tensile fractures observed at well WD-1 in the Kakkonda geothermal field; Kakkonda WD-1 sei de kansokusareta drilling induced tensile fracture ni yoru chikaku oryokuba no suitei  

Energy Technology Data Exchange (ETDEWEB)

This paper describes estimation of a stress field in the earth`s crust in the Kakkonda geothermal field. Formation micro imager (FMI) logging known as a crack detecting logging was performed in the well WD-1. This FMI logging has made observation possible on cracks along well axis thought to indicate size and direction of the crust stress, and drilling-induced tensile fractures (DTF). It was verified that these DTFs are generated initially in an azimuth determined by in-situ stress (an angle up to the DTF as measured counterclockwise with due north as a starting point, expressed in {theta}) in the well`s circumferential direction. It was also confirmed that a large number of cracks incline at a certain angle to the well axis (an angle made by the well axis and the DTF, expressed in {gamma}). The DTF is a crack initially generated on well walls as a result of such tensile stresses as mud pressure and thermal stress acting on ...

1997-05-27

430

Crystal field analysis of the energy level structure of Cs{sub 2}NaAlF{sub 6}:Cr{sup 3+}  

Energy Technology Data Exchange (ETDEWEB)

An analysis of the energy level structure of Cr{sup 3+} ions in Cs{sub 2}NaAlF{sub 6} crystal is performed using the exchange charge model (ECM) together with the crystal field analysis/microscopic spin Hamiltonian (CFA/MSH) computer package. Utilizing the crystal structure data, our approach enables modelling of the crystal field parameters (CFPs) and thus the energy level structure for Cr{sup 3+} ions at the two crystallographically inequivalent sites in Cs{sub 2}NaAlF{sub 6}. Using the ECM initial adjustment procedure, the CFPs are calculated in the crystallographic axis system centred at the Cr{sup 3+} ion at each site. Additionally the CFPs are also calculated using the superposition model (SPM). The ECM and SPM predicted CFP values match very well. Consideration of the symmetry aspects for the so-obtained CFP datasets reveals that the latter axis system matches the symmetry-adapted axis system related directly to the six Cr-F bonds well. Using the ECM ...

2006-06-07

431

Crystal field analysis of the energy level structure of Cs2NaAlF6:Cr3+  

International Nuclear Information System (INIS)

An analysis of the energy level structure of Cr3+ ions in Cs2NaAlF6 crystal is performed using the exchange charge model (ECM) together with the crystal field analysis/microscopic spin Hamiltonian (CFA/MSH) computer package. Utilizing the crystal structure data, our approach enables modelling of the crystal field parameters (CFPs) and thus the energy level structure for Cr3+ ions at the two crystallographically inequivalent sites in Cs2NaAlF6. Using the ECM initial adjustment procedure, the CFPs are calculated in the crystallographic axis system centred at the Cr3+ ion at each site. Additionally the CFPs are also calculated using the superposition model (SPM). The ECM and SPM predicted CFP values match very well. Consideration of the symmetry aspects for the so-obtained CFP datasets reveals that the latter axis system matches the symmetry-adapted axis system related directly to the six Cr-F bonds well. Using the ECM predicted CFPs as an input for the CFA/MSH ...

2006-06-07

432

Additives to lower and stabilize the viscosity of pyrolysis oils during storage  

Energy Technology Data Exchange (ETDEWEB)

The initial development of additives to stabilize the viscosity of biocrude during long-term storage has produced dramatic results. The additives investigated were ethyl acetate, methyl isobuyl ketone and methanol, acetone, methanol, acetone and methanol, and ethanol. These additives represent three chemical families, which all demonstrated the ability to drastically reduce the aging rate of biocrude, as defined by the increase in viscosity with time. Accelerated aging tests were run at 90{degree}C to screen the additives. The additives not only lowered the initial viscosity at 40{degree}C by half but also reduced the aging rate of a hot gas filtered pyrolysis oil made from hybrid poplar (NREL run 175) by factors of 1-18 compared to the original pure oil. With the best additive, methanol, at a 10 wt% level in the pyrolysis oil, the modified biocrude was still a single-phase liquid and still met the ASTM no. 4 diesel fuel ...

1997-09-01

433

Working paper on candidate mining sites for surface mining of western oil shales  

Energy Technology Data Exchange (ETDEWEB)

This report describes the selection of candidate surface mining sites for the development of oil shale resources in the western United States. The purpose of this study is to input the various scenarios into an economic mine model developed for underground oil shale mines in an earlier project. Site selection was a three-phase effort. Phase I consisted of a thorough review of available resource data, which resulted in a definition of surface mineable areas. Phase II was a detailed investigation of the regions identified in the initial phase. The end result of this task was a list of potential sites having favorable overburden, grade, shale thickness, and topography values. Phase III identified those sites from which a wide range of site specific parameters can be obtained for mine design and model testing purposes. This report describes the procedures used to obtain the candidate mining scenarios. Section 2.0 discusses the ...

1981-09-02

434

Use of single-well simulators and economic performance criteria to optimize fracturing treatment design  

Energy Technology Data Exchange (ETDEWEB)

Low-permeability reservoirs are currently being propped with sand, resin-coated sand, intermediate-density proppants, and bauxite. This wide range of proppant cost and performance has resulted in the proliferation of proppant selection models. Initially, a rather vague relationship between well depth and proppant strength dictated the choice of proppant. More recently, computerized models of varying complexity that use net-present-value (NPV) calculations have become available. The input is based on the operator's performance goals for each well and specific reservoir properties. Simpler, noncomputerized approaches include cost/performance comparisons and nomographs. Each type of model, including several of the computerized models, is examined here. By use of these models and NPV calculations, optimum fracturing treatment designs have been developed for such low-permeability reservoirs as the Prue in Oklahoma. Typical well conditions ...

1990-02-01

435

Thermal responses to 5. 6-GHz radiofrequency radiation in anesthetized rats. Effect of chlorpromazine  

Energy Technology Data Exchange (ETDEWEB)

Anesthetized rats were exposed to 5.6-GHz continuous-wave radiofrequency radiation (RFR) at an average power density of 60 mW/Sq. cm (average specific absorption rate 12 W/kg). Exposure was performed to raise colonic temperature from 38.5 to 39.5C. Following acute administration of chlorpromazine, body temperature exhibited a faster return to baseline temperature when exposure was discontinued. When exposure was initiated at 38.5C and continued until lethal temperature resulted, chlorpromazine-treated animals exhibited significantly shorter survival times than saline-treated animals. Thus, although chlorpromazine enhanced thermoregulatory efficiency at colonic temperature below 39.5 deg C, the drug caused increased susceptibility to terminal RFR. The present results, when compared with previous studies of irradiation at 2.8 GHz, indicate that the effects of chlorpromazine on thermal response to RFR during intermittent and ...

1988-01-01

436

The runaway instability of thick discs around black holes. II. Non constant angular momentum discs  

CERN Document Server

We present results from a comprehensive number of relativistic, time-dependent, axisymmetric simulations of the runaway instability of non-constant angular momentum thick discs around black holes. This second paper extends earlier results where only constant angular momentum discs were considered. All relevant aspects of the theory of stationary thick discs around rotating black holes, necessary to build the initial state in our simulations, are presented in great detail. The angular momentum of the discs is assumed to increase outwards with the radial distance according to a power law. The main simplifying assumptions of our approach are not to include magnetic fields and self-gravity in the discs. Furthermore, the dynamics of the spacetime is accounted for by computing the transfer of mass and angular momentum from the disc to the black hole through the event horizon : the evolution of the central black hole is assumed to ...

2004-01-01

437

The nucleon interaction and neutron matter from the renormalization group  

CERN Document Server

We show that the renormalization group decimation of modern nucleon potential models to low momenta results in a unique nucleon interaction V_{low k}. This interaction is free of short-ranged singularities and can be used directly in many-body calculations. The RG scaling properties follow directly from the invariance of the scattering phase shifts. We discuss the RG treatment of Fermi liquids. The RG equation for the scattering amplitude in the two particle-hole channels is given at zero temperature. The flow equations are simplified by retaining only the leading term in an expansion in small momentum transfers. The RG flow is illustrated by first studying a system of spin-polarized fermions in a simple model. Finally, results for neutron matter are presented by employing the unique low momentum interaction V_{low k} as initial condition of the flow. The RG approach yields the amplitude for non-forward scattering, which is ...

2002-01-01

438

Supplementation of pyruvate prevents palmitate-induced impairment of glucose uptake in C2 myotubes.  

Science.gov (United States)

Elevated fatty acid levels have been thought to contribute to insulin resistance. Repression of the glucose transporter 4 (GLUT4) gene as well as impaired GLUT4 translocation may be a mediator for fatty acid-induced insulin resistance. This study was initiated to determine whether palmitate treatment repressed GLUT4 expression, whether glucose/fatty acid metabolism influenced palmitate-induced GLUT4 gene repression (PIGR), and whether attempts to prevent PIGR restored palmitate-induced impairment of glucose uptake (PIIGU) in C2 myotubes. Not only stimulators of fatty acid oxidation, such as bezafibrate, AICAR, and TOFA, but also TCA cycle substrates, such as pyruvate, leucine/glutamine, and ?-ketoisocaproate/monomethyl succinate, significantly prevented PIGR. In particular, supplementing with pyruvate through methyl pyruvate resulted in nearly complete prevention of PIIGU, whereas palmitate treatment reduced the intracellular pyruvate level. ...

2011-07-23

439

Studies of initial stage in coal liquefaction. Effect of prethermal treatment condition with process solvent to increase oil yields; Ekika hanno no shoki katei ni kansuru kenkyu. Sekitan no maeshori joken to yozai koka  

Energy Technology Data Exchange (ETDEWEB)

Process solvent was hydrogenated in the brown coal liquefaction, to investigate the influence of it on the prethermal treatment and liquefaction. Consequently, it was found that the n-hexane soluble (HS) yield was improved. In this study, capacity of hydrogen transfer from solvent during prethermal treatment and effects of catalyst were investigated. Since prethermal treatment in oil was effective for improving the oil yield in the presence of hydrogen/catalyst or high hydrogen-donor solvent, influence of hydrogen-donor performance of solvent or addition of catalyst on the hydrogenation behavior of coal and the characteristics of products during prethermal treatment were investigated in relation to successive liquefaction results. As a result, it was found that the increase of HS yield was due to the acceleration of conversion of THF-insoluble using high hydrogen-donor solvent and/or by adding catalyst. It was also found that the use of high ...

1996-10-28

440

Studies of initial stage in coal liquefaction. 4. Radical formation and structural change with thermal decomposition of coal; Ekika hanno no shoki katei ni kansuru kenkyu. 4. Netsubunkai ni tomonau radical seisei kyodo to kozo henka  

Energy Technology Data Exchange (ETDEWEB)

In relation to coal liquefaction reaction, the effect of the coexistence of transferable hydrogen (TH) from process solvent on reduction of radical concentration and the effect of pre-heat treatment on average structure of coals were studied. In experiment, change in radical concentration with temperature rise was measured using the system composed of Yallourn coal and process solvent. The results are as follows. Process solvent with a wide boiling point range of 180-420{degree}C is effective in suppressing an increase in radical concentration even at higher temperature. The effect of hydrogen-donating solvent increases with TH. It was also suggested that high-boiling point constituents in solvent stabilize radicals even over 400{degree}C by vapor phase hydrogenation. The experimental results of pre-heat treatment are as follows. Although the conversion improvement effect of TH is equivalent to that of the model solvent, TH tends to produce ...

1996-10-28

441

Review of fires and fire control methods for nuclear air cleaning systems  

International Nuclear Information System (INIS)

The nuclear power industry has experienced four carbon based adsorbent fires in its history, one was of the Monticello Standby Gas Treatment System and other three were in various off-gas delay beds. Although, some of the latter may not be classified as a full fledged fires. There were a number of experiments performed relating to igniting carbon beds and experiments relating to attempts at extinguishing set fires reported in the literature. Review of these experiments indicates that fire resulting from decay heat of adsorbed radioactive iodine is not justified even under the somewhat unrealistic source terms still in effect. At the same time the non-nuclear chemical industry application of carbon base adsorbents for solvent recovery has resulted in numerous fires and significant property losses. Fire control systems installed in nuclear air cleaning systems in the US consists of water deluge. Accidental initiation of these ...

1987-05-01

442

Radiolabelled D_2 agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989  

International Nuclear Information System (INIS)

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of "3"5S-cysteamine, evaluation of "1"8F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various ...

443

Radiolabelled D/sub 2/ agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989  

Energy Technology Data Exchange (ETDEWEB)

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of /sup 35/S-cysteamine, evaluation of /sup 18/F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of ...

1988-10-15

444

Plasma dynamics in the PF-1000 device under full-scale energy storage: II. Fast electron and ion characteristics versus neutron emission parameters and gun optimization perspectives  

International Nuclear Information System (INIS)

Electron and ion beam dynamics of the PF-1000 facility were investigated for the first time at its upper energy limit (?1 MJ) in relation to neutron emission, the pinch's plasma ('target') characteristics and some other parameters with the help of a number of diagnostics with ns temporal resolution. Special attention was paid to the temporal and the spatial cross correlations of different phenomena. Results of these experiments are in favour of a neutron emission model based on ion beam-plasma interaction with three important features: (1) the plasma target is hot and confined during a few 'inertial confinement times'; (2) the ions of the main part of the beam are magnetized and entrapped around the pinch plasma target for a period longer than the characteristic time of the plasma inductive storage system and (3) ion-ion collisions (both fusion collisions, due to head-on impacts and Coulomb collisions) are responsible for neutron emission. Analysis has shown that ...

2007-06-21

445

Observing Evolution in the Supergranular Length Scale During Periods of Low Solar Activity  

CERN Document Server

We present the initial results of an observational study into the variation of the dominant length-scale of quiet solar emission: supergranulation. This length-scale reflects the radiative energy in the plasma of the upper solar chromosphere and transition region at the magnetic network boundaries forming as a result of the relentless interaction of magnetic fields and convective motions of the Sun's interior. We demonstrate that a net difference of ~0.5Mm in the supergranular emission length-scale occurs when comparing observations cycle 22/23 and cycle 23/24 minima. This variation in scale is reproduced in the datasets of multiple space- and ground-based instruments and using different diagnostic measures. By means of extension, we consider the variation of the supergranular length-scale over multiple solar minima by analyzing a subset of the Mt Wilson Solar Observatory (MWO) Ca II K image record. The observations and ...

2011-01-01

446

New options for simulating swivel momentum in car door hinges with neural networks. Neue Moeglichkeiten zur Simulation von Schwenkmomenten an Automobiltuerscharnieren mit Neuronalen Netzen  

Energy Technology Data Exchange (ETDEWEB)

The generation of a defined swivel momentum in car door hinges depends on numerous constructional and technical manufacturing parameters. If these parameters and their influence are to be investigated, then in addition to detailed experiments with variations in the parameters, methods are also required which enable the measuring data produced to be assessed in such a way that, in general, the non-linear relationships between initial and target size can be described sufficiently accurately. This paper explains the parameter reduction necessary in the experimental investigation, gives the results of the data assessment with conventional statistical methods and describes in particular the use of artificial neural networks (ANN) to construct so-called 'neuro hinge models' on the basis of the data resulting from the experiments. Parameter variations can be simulated with the hinge models and in this way optimal ...

1999-04-01

447

Nanostructuring the graphite basal plane by focused ion beam patterning and oxygen etching  

International Nuclear Information System (INIS)

Ga"+ focused ion beam (FIB) patterning was used to structure highly oriented pyrolytic graphite surfaces with square, periodic arrays of amorphous carbon defects (mesh sizes: 300 nm-2 #mu#m). Controlled oxygen etching of these arrays leads to matrices of uniform, orientationally aligned, nm-sized, hexagonal holes. The properties of the resulting hole assembly (hole depths and lateral hole dimensions) have been investigated by means of atomic force microscopy, scanning electron microscopy and FIB sectioning. The hole dimensions and uniformity both depend on the FIB parameters and etching conditions. Etching temperatures from 500 to 700 deg. C were applied. Initial etch rates of up to 10"6 C s"-"1 per individual hole were observed when using oxygen pressures of 200 mbar. For an etch temperature of 590 deg. C the rate of etching of individual holes was found to depend measurably on the inter-hole separation. This confirms that the associated ...

2006-12-14

448

Matter and dynamics in closed cosmologies  

International Nuclear Information System (INIS)

To systematically analyze the dynamical implications of the matter content in cosmology, we generalize earlier dynamical systems approaches so that perfect fluids with a general barotropic equation of state can be treated. We focus on locally rotationally symmetric Bianchi type IX and Kantowski-Sachs orthogonal perfect fluid models, since such models exhibit a particularly rich dynamical structure and also illustrate typical features of more general cases. For these models, we recast Einstein's field equations into a regular system on a compact state space, which is the basis for our analysis. We prove that models expand from a singularity and recollapse to a singularity when the perfect fluid satisfies the strong energy condition. When the matter source admits Einstein's static model, we present a comprehensive dynamical description, which includes the qualitative asymptotic behavior, of models in the neighborhood of the Einstein model; the results refute earlier ...

2005-04-15

449

Loss of flow incident - Simulation and measurements in the MPR  

International Nuclear Information System (INIS)

As part of the Probabilistic Safety Analysis of the Multi Purpose Reactor, MPR, the list of Postulated Initiating Events was analyzed and one of these PIEs corresponds to the Loss of Coolant Flow. It is well known that during the operation life of a research reactor a LOFA could eventually occur and, once this event takes place, in time detection and automatic actions, thanks to the engineering safety features of the system, will mitigate the incident evolution. The postulated event corresponds to a loss of flow due to a total loss of power supply. The goal of the present work is to provide a general description and the engineering safety features of the MPR, as well as describe the sequence of scenarios during a LOFA. Temporal evolution of main parameters is presented, also. During Stage A of the Commissioning Program measurements of the core cooling system pump coast-down were performed in order to validate previous simulation results, as ...

1999-10-26

450

Iterative Dense Correspondence Correction Through Bundle Adjustment Feedback-Based Error Detection  

Energy Technology Data Exchange (ETDEWEB)

A novel method to detect and correct inaccuracies in a set of unconstrained dense correspondences between two images is presented. Starting with a robust, general-purpose dense correspondence algorithm, an initial pose estimate and dense 3D scene reconstruction are obtained and bundle-adjusted. Reprojection errors are then computed for each correspondence pair, which is used as a metric to distinguish high and low-error correspondences. An affine neighborhood-based coarse-to-fine iterative search algorithm is then applied only on the high-error correspondences to correct their positions. Such an error detection and correction mechanism is novel for unconstrained dense correspondences, for example not obtained through epipolar geometry-based guided matching. Results indicate that correspondences in regions with issues such as occlusions, repetitive patterns and moving objects can be identified and corrected, such that a more accurate set of ...

2009-11-23

451

Inverse spinel materials. A new class of high voltage cathode materials for Li-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

The influence of Cr on the structure and electrochemical properties of LiCoVO{sub 4} was studied using X-Ray diffraction, scanning electron microscopy, Raman Spectroscopy and cycle tests. Doping levels up to 10 mol% were achieved, which improved the electrochemical stability of the structure of LiCoVO{sub 4}, resulting in a significant increase in the initial charge and discharge capacity. The Raman spectroscopy data for the Cr-doped LiCoVO{sub 4} is similar as for LiCoVO{sub 4}. The replacement of a dopant for the Co-ion in the inverse spinel structure causes several Raman shifts. The X-ray diffraction patterns show no new phases and combined with the Raman spectroscopy data it is concluded that the Cr dopant will be located at the octahedral site (16d) where they create an electronic pathway that enhances the electronic conductivity. However, the capacity dropped significantly after prolonged cycling, which is due to the diffusion of V{sup ...

2003-07-01

452

Integrated verification test of Severe Accident Analysis Code SAMPSON in super Simulation 'IMPACT' system  

International Nuclear Information System (INIS)

The Four years of the IMPACT, 'Integrated Modular Plant Analysis and Computing Technology', project Phase 1 have been completed. The verification study of Severe Accident Analysis Code SAMPSON prototype developed in Phase 1 was conducted in two steps. First, each analysis module was run independently and analysis results were compared and verified against separate-effect test data with good results. Second, with the Simulation Supervisory System, up to 11 analysis modules were executed concurrently in the parallel environment (currently, NUPEC uses IBM-SP2 with 72 process elements), to demonstrate the code capability and integrity. The target plant was Surry as a typical PWR and the initiation events were a 10-inch cold leg failure. The analysis is divided to two cases; one is in-vessel retention analysis when the gap cooling is effective (In-vessel scenario test), the other is analysis of phenomena event is extended to ...

1999-07-01

453

In field nuclear forensics: An overview of applicable instrumentation  

International Nuclear Information System (INIS)

Recent seizures of nuclear materials, and particularly of fissionable nuclear materials, have resulted in an increased awareness of the need for fieldable instrumentation for the detection and characterization of suspect packages and materials. The ability to perform in-field assessments of materials contained in suspect packages is important for several reasons. First, and most importantly, determination of the type and quantity of material provides information critical to personnel safety. The personnel at potential risk may include both the general population in the area of the package and incident response personnel. Additionally, it would be advantageous to gain information that could result in attribution of the suspect package to a particular facility or pathway as soon as possible after interception. Limited access to a suspect package could also require the use of fieldable characterization instrumentation as opposed to transporting ...

1997-06-12

454

Implementing climate wise at Johnson & Johnson  

Energy Technology Data Exchange (ETDEWEB)

Johnson & Johnson has had a formal energy program since the early 1970`s. A corporate energy department was formed as a result of the disruption of energy supplies and rising energy costs. Johnson & Johnson is a decentralized company with many independent operating companies throughout the world. The corporate energy department cuts across the different levels of management to delivery energy related information to the actual implementers at all of our locations worldwide. Like many other energy programs, Johnson & Johnson`s program had highs and lows depending on worldwide energy activities. Unlike many other corporate programs that were disbanded in the late 1980`s, our program remained in place, although there was not a high level of interest or attention. In the early 1990`s, the link was made between electricity generation and greenhouse gas emissions, initially by the Green Lights program and strongly reinforced by the United ...

1996-05-01

455

Implementation Plan. Environmental Restoration and Waste Management Programmatic Environmental Impact Statement  

Energy Technology Data Exchange (ETDEWEB)

In accordance with the Department of Energy`s National Environmental Policy Act implementing procedures in Volume 10 of the Code of Federal Regulations, Section 1021,312, the Environmental Restoration and Waste Management Programmatic Environmental Impact Statement Implementation Plan has two primary purposes: to provide guidance for the preparation of the Programmatic Environmental Impact Statement and to record the issues resulting from the scoping and the extended public participation process. The Implementation Plan identifies and discusses the following: background of Environmental Restoration and Waste Management activities, the purpose of the Programmatic Environmental Impact Statement, and the relationship of the Programmatic Environmental Impact Statement to other Departmental initiatives (Chapter 1); need and purposes for action (Chapter 2); scoping process and results of the public participation program in ...

1994-01-01

456

Fatigue crack detection in aircraft skin structures using eddy current array technique  

International Nuclear Information System (INIS)

Detection of fatigue damage cracks in aircraft skin structures is an ongoing NDT challenge. Cracks growing rate is difficult to predict, and for this reason, it is important to detect them as soon as possible to avoid a catastrophic break. Eddy current methods are known and well-accepted techniques which are relatively simple to carry out. However, with conventional inspection of airframe structures using standard driver-pickup eddy current probes, it is difficult to detect small fatigue cracks initiated in the second layer of the skin and in the shadow region at fastener holes. Such difficulty is related to fasteners length and their spacing which reduces test sensitivity. This report explains the development of improved eddy current probe/technique to detect and visualize fatigue cracks in fasteners. In this study, an eddy current array probe was evaluated and new coil design was suggested. Several tests were conducted on an A-300 circumferential joint sample ...

2004-01-01

457

Effects of oxygen, copper and acid chlorides on denting corrosion  

Energy Technology Data Exchange (ETDEWEB)

The effect of dissolved oxygen and copper on denting corrosion at 280/sup 0/C in solutions of NaCl at pH 9 with ammonia was investigated using a packed tube/support plate crevice in a laboratory simulation. The onset of corrosion was detected with a hydrogen analyzer sensitive to 0.2 ppB. In the absence of copper, rapidly rising hydrogen concentrations were detected only when the product of the chloride and oxygen concentrations were detected only when the product of the chloride and oxygen concentrations in the boiler-water exceeded 25 (ppM)/sup 2/, but at these high concentrations, unheated low-carbon steel surfaces in the system were as sensitive to corrosion as the heated crevice. When copper metal was present in the feed system, corrosion of the heated crevice occurred in the absence of oxygen, provided the copper had previously been exposed to dissolved oxygen. Dosing hydrazine into the feedwater eventually suppressed the ability of copper to initiate ...

1986-07-01

458

Effects of nitrogen on the passivity and the pitting corrosion of stainless steels; Stainless ko no fudotai to koshoku ni oyobosu chisso no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Described herein are effects of nitrogen dissolved in steel on passivity and pitting corrosion, as one of the major corrosion phenomena observed in stainless steel. Mechanisms involved in controlling pitting corrosion by nitrogen are also discussed. Nitrogen contained in austenic stainless steel is concentrated in the surface area, in particular in the vicinity of the interface between the passive film and metal matrix. Nitrogen tends to decrease critical current density in an acid, when it is added to steel of high critical current density (approximately 1mA/cm{sup 2} or higher). This phenomenon is considered to result from accumulation of nitrogen preferentially in the surface area to prevent dissolution of steel. Nitrogen dissolved in the austenic phase improves resistance of the steel to pitting corrosion. This phenomenon is considered to result from controlled decrease in pH level during the initial stage of pitting ...

1998-09-15

459

Effect of rich and high turbulence combustion on emissions and flame behavior in a direct-injection diesel engine; Chokusetsu funshashiki diesel kikan ni okeru haki tokusei to kaen kyodo ni oyobosu kano koranryu nensho no eikyo  

Energy Technology Data Exchange (ETDEWEB)

This study tried to reduce NO{sub x} and particulate emissions simultaneously in a high speed direct-injection diesel engine. Fuel-rich combustion was used to reduce NO{sub x} emission at initial combustion stage and high turbulence combustion was used to reduce particulate emission at diffusion combustion stage. Experiments were carried out to investigate the effects of high squish combustion chambers with small throat on combustion process and exhaust emissions. Results showed that in the high squish combustion chamber, both NO{sub x} and particulate emissions reduced with retarded injection timing. Endoscopic high speed photography was employed to analyze experimental results. In the original combustion chamber at the early combustion stage, the high luminosity flame tended to spread out of the cavity. Fuel-rich mixture burned slowly over the piston crown. In the high squish combustion chamber, flame rotated violently ...

1999-09-25

460

EXPLORATORY RESEARCH ON NOVEL COAL LIQUEFACTION CONCEPT  

Science.gov (United States)

All first-stage experimental tests were completed for Task 4 (and the Contract). The first-stage one-liter autoclave tests that were made were duplicates of Run 41-LA. The conditions used were chosen last quarter to reduce the cost of the first-stage of the process from those used at the conclusion of Task 3. Filtration and second-stage tests were made using the products of the first-stage tests. Post-second-stage filtration, tested as an alternative to interstage (pre-second- stage) filtration, resulted in low filtration rates. Different catalyst loadings and type and residence time for second-stage hydrotreating were explored. Longer residence times did not result in significantly more resid conversion. Higher catalyst loadings were more effective in converting the resid at the same residence time. The material and elemental balances for the first-stage were completed. The material and elemental balances for the second-stage were ...

1998-06-30

461

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM  

Energy Technology Data Exchange (ETDEWEB)

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period January 1, 2005 through March 31, 2005. The following tasks have been completed. First, the renovation of the new Combustion Laboratory is nearly complete, and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building is in the final stages. Second, the fabrication and manufacture of the CFBC Facility is being discussed with a potential contractor. Discussions with potential contactor regarding the availability of materials and current machining capabilities have resulted in the modification of the original designs. The selection of the fabrication contractor for the CFBC Facility is expected during the next quarter. Third, co-firing experiments conducted with coal and chicken waste have been ...

2005-04-30

462

Conceptual design of the Fast-Liner Reactor (FLR) for fusion power  

International Nuclear Information System (INIS)

The generation of fusion power from the Fast-Liner Reactor (FLR) concept envisages the implosion of a thin (3-mm) metallic cylinder (0.2-m radius by 0.2-m length) onto a preinjected plasma. This plasma would be heated to thermonuclear temperatures by adiabatic compression, pressure confinement would be provided by the liner inertia, and thermal insulation of the wall-confined plasma would be established by an embedded azimuthal magnetic field. A 2- to 3-mu s burn would follow the approx. 10"4 m/s radial implosion and would result in a thermonuclear yield equal to 10 to 15 times the energy initially invested into the liner kinetic energy. For implosions occurring once every 10 s a gross thermal power of 430 MWt would be generated. The results of a comprehensive systems study of both physics and technology (economics) optima are presented. Despite unresolved problems associated with both the physics and technology of the FLR, ...

463

Cogeneration in air separation cryogenic plants; Cogeracao em plantas criogenicas de separacao de ar  

Energy Technology Data Exchange (ETDEWEB)

A thermal and economic study, carried on by using the first and second law of thermodynamics concepts demonstrated the economic feasibility of the cogeneration system, and proposed modifications to be done in the studied cryogenic plant, a typical T-240 NA MPL3 plant. The thermodynamic analysis showed that the second law efficiency of the processes could be improved, together with a 12% electric energy consumption reduction. Four cogeneration schemes were analyzed with both the first and second laws of thermodynamics and, then, the economic analysis was performed. Rankine, Brayton, Otto and Combined gas-steam basic cycles were used in this analysis.The combined gas-steam cycle was shown to be more economically feasible than others. Thermal and electric loads were well balanced, resulting in a higher second law efficiency. Although the initial investment for the modification was higher, the savings resulted to be higher, ...

2000-07-01

464

Co-Authorship Networks in the Digital Library Research Community  

CERN Document Server

The field of digital libraries (DLs) coalesced in 1994: the first digital library conferences were held that year, awareness of the World Wide Web was accelerating, and the National Science Foundation awarded $24 Million (U.S.) for the Digital Library Initiative (DLI). In this paper we examine the state of the DL domain after a decade of activity by applying social network analysis to the co-authorship network of the past ACM, IEEE, and joint ACM/IEEE digital library conferences. We base our analysis on a common binary undirectional network model to represent the co-authorship network, and from it we extract several established network measures. We also introduce a weighted directional network model to represent the co-authorship network, for which we define $AuthorRank$ as an indicator of the impact of an individual author in the network. The results are validated against conference program committee members in the same period. The ...

2005-01-01

465

Characterization of atmospheric aerosol near motor way: Bassa Valle Susa (Italy); Caratterizzazione dell`aerosol atmosferico in prossimita` di un`autostrada: Bassa Valle Susa  

Energy Technology Data Exchange (ETDEWEB)

Results related to the experimental measurement campaign to characterize atmospheric aerosol carried out near Avigliana (Turin) from 18 to 22 October 1994 are presented in this paper. In the frame of the project aimed at evaluating the impact of the mountain motor way A-32 Rivoli-Bardonecchia-Frejus on the Susa Valley environment and on man the present measurement campaign is the second, and last, one envisaged in the project. The sampling place is in the initial part of the Susa Valley while previous measurements were carried out in the high part of it. Mass mean concentrations result greater in the low than in the high part of the valley approximately by a factor of 3. It is not possible to prove a difference between the 3 sampling positions transversely placed from 20 to 80 m. in comparison with the motor way axis. Whereas mass mean concentrations dropped substantially due to atmospheric precipitations during the last ...

1995-10-01

466

Building an internet-based workflow system - the case of Lawrence Livermore National Laboratories` Zephyr project  

Energy Technology Data Exchange (ETDEWEB)

Lawrence Livermore National Laboratories` Zephyr System provides a showcase for the ways in which emerging technologies can help streamline procurement processes and improve the coordination between participants in engineering projects by allowing collaboration in ways that have not been possible before. The project also shows the success of a highly pragmatic approach that was initiated by the end user community, and that intentionally covered standard situations, rather than aiming at also automating the exceptions. By helping push purchasing responsibilities down to the end user, thereby greatly reducing the involvement of the purchasing department in operational activities, it was possible to streamline the process significantly resulting in time savings of up to 90%, major cost reductions, and improved quality. Left with less day-to- day purchasing operations, the purchasing department has more time for strategic tasks such as selecting ...

1998-04-01

467

Analytical solution for Joule-Thomson cooling during CO2 geo-sequestration in depleted oil and gas reservoirs  

Energy Technology Data Exchange (ETDEWEB)

Mathematical tools are needed to screen out sites where Joule-Thomson cooling is a prohibitive factor for CO{sub 2} geo-sequestration and to design approaches to mitigate the effect. In this paper, a simple analytical solution is developed by invoking steady-state flow and constant thermophysical properties. The analytical solution allows fast evaluation of spatiotemporal temperature fields, resulting from constant-rate CO{sub 2} injection. The applicability of the analytical solution is demonstrated by comparison with non-isothermal simulation results from the reservoir simulator TOUGH2. Analysis confirms that for an injection rate of 3 kg s{sup -1} (0.1 MT yr{sup -1}) into moderately warm (>40 C) and permeable formations (>10{sup -14} m{sup 2} (10 mD)), JTC is unlikely to be a problem for initial reservoir pressures as low as 2 MPa (290 psi).

2010-05-21

468

A new kind of immobilized lipase in organic solvent and its structure model.  

Science.gov (United States)

In this paper, we used Ca-alginate gel beads coated with polyetheneimine and glutaraldehyde to adsorb Expansum penicillium lipase. The immobilized lipase catalyzed esterification of 1-dodecanol with dodecanoic acid in benzene. The results show that when the concentration of Ca-alginate, polyetheneimine (PEI) and glutaraldehyde is 1%, 6% and 1%, respectively, the activity of the immobilized lipase and the amount of adsorbed protein are the highest. The immobilized lipase is better than the SDS-immobilized lipase. The activity of the immobilized lipase connected by glutaraldehyde is higher than the activity of that without glutaraldehyde. The initial rate of the immobilized lipase and lyophilized lipase powder is 5.9 x 10(2) nmol/min.mgpr and 2.8 x 10(1) nmol/min.mgpr, respectively. After the immobilized lipase catalyzed the esterification reaction at 37 degrees C for about 12 hours, 93.3% of 1-dodecanol was converted to ester, but for ...

1994-04-15

469

Scale-up of two-phase flow in heterogeneous chalk. Matrix properties  

Energy Technology Data Exchange (ETDEWEB)

This investigation presents scale-up of a detailed heterogeneous geostatistical model to a full field reservoir simulation model, considering both single and two-phase flow properties. The model represents a typical low permeability Danish North Sea chalk reservoir and includes capillary pressure and saturation end-point variations. Two new up-scaling methods has been investigated, all based on fine scale simulation on a cross section of the geomodel. The first methods assumes piston style behaviour and a coupled viscosity is introduced into the basic Darcy`s equations. The second method is a modification of the JBN method traditionally applied in analysing results from core flooding experiments, which emerged as the most successful and therefore also the recommended method. 1. In addition to the up scaling work we review the Equivalent Radius Method for capillary pressure normalisation with explicit derivation of type functions for Maastrichtian and Danian chalk ...

1998-02-01

470

TYPE Ib/c SUPERNOVAE IN BINARY SYSTEMS. I. EVOLUTION AND PROPERTIES OF THE PROGENITOR STARS  

International Nuclear Information System (INIS)

We investigate the evolution of Type Ib/c supernova (SN Ib/c) progenitors in close binary systems, using new evolutionary models that include the effects of rotation, with initial masses of 12-25 M_s_u_n for the primary components, and of single helium stars with initial masses of 2.8-20 M_s_u_n. We find that, despite the impact of tidal interaction on the rotation of primary stars, the amount of angular momentum retained in the core at the presupernova stage in different binary model sequences converges to a value similar to those found in previous single star models. This amount is large enough to produce millisecond pulsars, but too small to produce magnetars or long gamma-ray bursts. We employ the most up-to-date estimate for the Wolf-Rayet mass-loss rate, and its implications for SN Ib/c progenitors are discussed in detail. In terms of stellar structure, SN Ib/c progenitors in binary systems at solar metallicity are predicted to have a ...

2010-12-10

471

NORTH HILL CREEK 3-D SEISMIC EXPLORATION PROJECT  

Energy Technology Data Exchange (ETDEWEB)

Wind River Resources Corporation (WRRC) received a DOE grant in support of its proposal to acquire, process and interpret fifteen square miles of high-quality 3-D seismic data on non-allotted trust lands of the Uintah and Ouray (Ute) Indian Reservation, northeastern Utah, in 2000. Subsequent to receiving notice that its proposal would be funded, WRRC was able to add ten square miles of adjacent state and federal mineral acreage underlying tribal surface lands by arrangement with the operator of the Flat Rock Field. The twenty-five square mile 3-D seismic survey was conducted during the fall of 2000. The data were processed through the winter of 2000-2001, and initial interpretation took place during the spring of 2001. The initial interpretation identified multiple attractive drilling prospects, two of which were staked and permitted during the summer of 2001. The two initial wells were drilled in September and October of ...

2004-05-06

472

The role of acid incubation in rapid immobilization of hydrogen-producing culture in anaerobic upflow column reactors  

Energy Technology Data Exchange (ETDEWEB)

An approach of acidification was examined on formation of hydrogen-producing granules and biofilms in upflow column-shaped reactors. The reactors were fed with synthetic glucose wastewater and operated at 37 C and pH 5.5. The acclimated anaerobic culture was inoculated in four reactors designated R1, R2, R3 and R4, with R3 and R4 filled with granular activated carbon as support medium. To unveil the roles of acidification, microbial culture in R2 and R3 was subject to an acid incubation for 24 h by shifting the culture pH from 5.5 to 2.0. The experimental results suggested that the acidification substantially accelerated microbial granulation, but not biofilm formation. Microbial activities were inhibited by the acid incubation for about 78 h, resulting in the retarded formation of biofilms of the acidified culture. Reducing culture pH resulted in improvement in cell surface physicochemical properties favoring microbial ...

2008-10-15

473

The denoising of Monte Carlo dose distributions using convolution superposition calculations  

International Nuclear Information System (INIS)

Monte Carlo (MC) dose calculations can be accurate but are also computationally intensive. In contrast, convolution superposition (CS) offers faster and smoother results but by making approximations. We investigated MC denoising techniques, which use available convolution superposition results and new noise filtering methods to guide and accelerate MC calculations. Two main approaches were developed to combine CS information with MC denoising. In the first approach, the denoising result is iteratively updated by adding the denoised residual difference between the result and the MC image. Multi-scale methods were used (wavelets or contourlets) for denoising the residual. The iterations are initialized by the CS data. In the second approach, we used a frequency splitting technique by quadrature filtering to combine low frequency components derived from MC simulations with high ...

2007-09-07

474

ERRICCA radon model intercomparison exercise  

Energy Technology Data Exchange (ETDEWEB)

Numerical models based on finite-difference or finite-element methods are used by various research groups in studies of radon-222 transport through soil and building materials. Applications range from design of radon remediation systems to more fundamental studies of radon transport. To ascertain that results obtained with these models are of good quality, it is necessary that such models are tested. This document reports on a benchmark test organized by the EU project ERRICCA: European Research into Radon in Construction Concerted Action. The test comprises the following cases: 1) Steady-state diffusive radon profiles in dry and wet soils, 2) steady-state entry of soil gas and radon into a house, 3) time-dependent radon exhalation from a building-material sample. These cases cover features such as: soil heterogeneity, anisotropy, 3D-effects, time dependency, combined advective and diffusive transport of radon, flux calculations, and partitioning of radon between ...

1999-04-01

475

Top of tubesheet cracking in Bruce A NGS steam generator tubing - recent experience  

Energy Technology Data Exchange (ETDEWEB)

During the Bruce A Nuclear Generating Station (BNGS-A) Unit 1 1997 planned outage, a dew point search method identified a leak in one steam generator(SG) tube. Subsequently, the tube was inspected with all available eddy current probes and removed for examination. The initial inspection results and metallurgical examination of the removed tube confirmed that the leak was due to intergranular attack/stress corrosion cracking (IGA/SCC) emanating from the secondary side of the tube at the top of the tubesheet location. Subsequently, eddy current and ultrasonic indications were found at the top of the tubesheet of other Alloy 600 SG tubes. To investigate the source of the indications and to validate the inspection probes, sections of 40 tubes with various levels of damage were removed. The metallurgical examination of the removed sections showed that both secondary side and primary side initiated, circumferential, stress ...

1998-07-01

476

The effect of age hardening on creep crack growth in alloy 800  

International Nuclear Information System (INIS)

The creep crack growth properties of two versions of Alloy 800 have been compared at 500 and 600"0C in the Grade II condition in tests up to 10"4 hours duration. The two alloys were a low carbon alloy containing (wt.%) 0.024 C, 0.5 Ti, 0.3 Al (Alloy B) and a higher carbon alloy containing (wt.%) 0.038 C, 0.2-0.3 Ti, 0.2-3.0 Al (Alloy J). At 600"0C, Alloy B attained maximum age hardening in 10"2 hours, whereas J did not harden significantly in time up to 10"4 hours. Both alloys age hardened at 550"0C with Alloy J hardening more rapidly than B. The creep displacements and displacement rates in small compact tension specimens at 600"0C were smaller than Alloy B than in Alloy J. However, failure times were shorter in Alloy B because of lower displacements for crack initiation and propagation and higher crack growth rates. At 550"0C the displacements for initiation and propagation in Alloy J were smaller than at 600"0C. A consequence of this ...

477

Study of the effect of noncondensable gas on heat transfer phenomena in horizontal steam generator of pactel facility with CATHARE2 V1.5a  

International Nuclear Information System (INIS)

Lappeenranta University of Technology (LTKK) and VTT Energy carried out a series of preliminary tests in 1999 to study the behavior of noncondensable (NC) gases in VVER geometry. The tests aimed at studying the effect of NC gases on system thermal-hydraulics and on heat transfer in a horizontal steam generator (HSG). The system behavior can be affected by hydrogen produced in the core in case of a severe accident, by nitrogen from hydro-accumulators released into the primary circuit in case of a loss-of-coolant accident (LOCA) and more generally by any NC gas in all cases where cooling is ensured by natural circulation. A secondary objective of the tests - the first series of tests ever performed with NC gas with PACTEL - was to find out, if the instrumentation of PACTEL was adequate for this type of tests and if it was functioning properly. This paper presents the measured and calculated (CATHARE code version V15a mod 2.1) results of the test NCg-l. It was carried ...

2001-03-20

478

Secure data communication for safeguards implementation  

International Nuclear Information System (INIS)

Full text: Secure, reliable and cost-effective communications are becoming an increasingly important tool for safeguards verification. This trend began with the initiation of remote monitoring implementation, where secure and cost effective data communications were required both to satisfy the confidentiality requirements of Member States and in order to meet the rigorous data authenticity requirements which allow the International Atomic Energy Agency (IAEA) to draw credible and independent conclusions. In addition, the implementation of additional protocols and integrated safeguards increases the importance of information (obtained in the course of an inspection, visit, complementary access or design information verification) being analyzed and corroborated with other information sources stored at IAEA Headquarters or Regional Offices, often while the inspector is still on-site. This requires the capability of enabling the inspector, wherever he is in the field, ...

2006-10-16

479

SUPPLEMENTAL COLUMBIA RIVER PROTECTION ACTIVITIES AT THE DEPARTMENT OF ENERGY HANFORD SITE: 2006 TECHNICAL PEER REVIEW  

Energy Technology Data Exchange (ETDEWEB)

Prompted by a $10 million Congressional allocation to identify supplemental actions to protect the Columbia River from groundwater contamination beneath the Hanford Reservation, the U. S. Department of Energy (DOE) Environmental Management (EM) Office of Clean-up Technology identified twenty-three potential technical projects and then down-selected ten of these for further evaluation. An independent expert peer review was conducted for the ten down-selected proposals. The review panel consisted of twenty-three recognized subject matter experts that broadly represented academia, industry, and federal laboratories. Of the initial ten proposals reviewed, one was given unconditional support, six were given conditional support, and three were not supported as proposed. Three additional proposals were then submitted by DOE for review--these proposals were structured, in part, to respond to the initial round of technical peer review comments. Peer ...

2006-12-20

480

Rate and mechanism of the atmospheric degradation of 2 H-heptafluoropropane (HFC-227)  

Energy Technology Data Exchange (ETDEWEB)

The atmospheric chemical behaviour of 2H-Heptafluoropropane (CF[sub 3]CHFCF[sub 3], HFC-227) with respect to its rate and mechanism of degradation in the troposphere has been investigated. The rate coefficient for the reaction of HFC-227 with OH radicals has been determined in direct time resolved experiments using a combination of laser-pulse initiation and LIF. In the temperature range T=298-463 K the Arrhenius expression k(T)=(3.8[+-]0.8) 10[sup -13] exp(-1596[+-]77 K/T) cm[sup 3]/s, which corresponds to k (298 K) = (1.8[+-]0.3) 10[sup -15] cm[sup 3]/s, was found. The mechanism of the atmospheric degradation of HFC-227 has been investigated using both, laser-pulse initiated/time resolved and UV photolysis/FTIR product studies. It is concluded that the major carbonyl products are CF[sub 3]COF and CF[sub 2]O which result from the decomposition of the oxy radical CF[sub 3]CF(O)CF[sub 3] by C-C bound fission. The rate ...

1994-02-01

481

Radial dose distribution of 6.0 MeV/n #alpha#-particle in water  

International Nuclear Information System (INIS)

For the study of radiation biology and its application to radiotherapy, the double differential cross section of electron emission from water vapor induced by 6.0 MeV alpha particle beam is measured. The energy spectra of electrons ranging 7- 10000 eV are detected by the electrostatic analyzer and micro channel plate. The measurements are made at angles between 20 and 160 degrees. With use of this data set, the radial dose distribution in water is calculated by using KURBUC code. It is the Monte Carlo type code of the electron transport process, where the track of the electron is simulated through each individual interactions including elastic scattering, ionization cross section and total excitation cross section in case that electrons with certain energy are put in the liquid-density water. In order to understand the effect of radiation when the particle flux is injected in the human body like radiotherapy using accelerator beam, the dose distribution in the biological substances is ...

2003-08-17

482

Prospective evaluation of femoral head viability following femoral neck fracture  

International Nuclear Information System (INIS)

The bone scans of 33 patients (pts) with recent subcapital fractures (fx) of the femur were evaluated prospectively to determine their value in predicting femoral head visability. Each of the 33 pts (ll men, 22 women, age range 30-92) had a pre-operative bone scan within 72 hrs of the fx (23 pts within 24 hrs). Anterior and posterior planar views of both hips and pinhole views (50% of pts) were obtained 2 hrs after administration of Tc-99m HDP. The femoral head was classified as perfused if it showed the same activity as the opposite normal side or if it showed only slightly decreased activity. Femoral heads showing absent activity were classified as nonperfused. Overall, 20 of the 33 pts showed a photopenic femoral head on the side of the fx. Only 2 pts showed increased activity at hte site of the fx. Internal fixation of the fx was performed in 23 pts, 12 of whom had one or more follow-up scans. Five of these 12 pts showed absent femoral head activity on their ...

1984-06-05

483

Meadow voles, Microtus pennsylvanicus, have the capacity to recall the "what", "where", and "when" of a single past event.  

Science.gov (United States)

Some non-human animals may possess the ability to recall the "what", "where", and "when" of a single past event. We tested the hypothesis that male meadow voles possess the capacity to recall the "what", "where", and "when" of a single past event associated with mate selection in two experiments. Briefly, male voles were allowed to explore an apparatus that contained two chambers. One chamber contained a day-20 pregnant female (24 h prepartum). The other chamber contained a sexually mature female that was neither pregnant nor lactating (REF female). Twenty-four hour after the exposure, the males were placed in the same apparatus, which was empty and clean. At this time, the pregnant female would have entered postpartum estrus (PPE), a period of heightened sexual receptivity. Males initially chose and spent significantly more time investigating the chamber that originally housed the pregnant female (now a PPE female) than the chamber that originally housed the REF ...

2007-07-26

484

Laser-assisted solar cell metallization processing: Final report for the period September 13, 1983 to September 30, 1986  

Energy Technology Data Exchange (ETDEWEB)

Laser-assisted processing techniques for producing high-quality solar cell metallization patterns have been investigated, developed, and characterized. During the early stages, preliminary investigations were carried out on a variety of promising laser-assisted metallization schemes, and the best of these was selected for further development. A comprehensive literature search initially yielded information on state-of-the-art laser-assisted techniques for metal deposition such as laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. Initial experiments on laser-enhanced electroplating yielded very promising results with linewidths as narrow as 25 ..mu..m and local plating speeds as high as 12 ..mu..m/s being achieved. Metal deposition experiments were carried out utilizing laser-assisted pyrolysis of a variety of metal-bearing polymer films and metallo-organic inks ...

1986-01-08

485

Internalized insulin-receptor complexes are unidirectionally translocated to chloroquine-sensitive degradative sites. Dependence on metabolic energy  

Energy Technology Data Exchange (ETDEWEB)

Insulin receptors on the surface of isolated rat adipocytes were photoaffinity labeled at 12 degrees C with the iodinated photoreactive insulin analogue, 125I-B2 (2-nitro-4-azidophenylacetyl)-des-PheB1-insulin, and the pathways in the intracellular processing of the labeled receptors were studied at 37 degrees C. During 37 degrees C incubations, the labeled 440-kDa insulin receptors were continuously internalized (as assessed by trypsin inaccessibility) and degraded such that up to 50% of the initially labeled receptors were lost by 120 min. Metabolic poisons (0.125-0.75 mM 2,4-dinitrophenol (DNP) and 1-10 mM NaF), which led to dose-dependent depletion of adipocyte ATP pools, inhibited receptor loss, and caused up to 3-fold increase in intracellular receptor accumulation. This effect was due to inhibition of intracellular receptor degradation, and there was no apparent effect of the metabolic poisons on initial internalization of the receptors. ...

1988-04-25

486

Initial review of the treatment operations at the Installation Logistics Center, Fort Lewis, Washington  

Energy Technology Data Exchange (ETDEWEB)

An initial review was conducted of the current treatment operations for remediation of groundwater contaminated with trichloroethene (TCE) at the Fort lewis Logistics Center. Results from this review indicate the two pump-and-treat systems are effectively containing the TCE plume within the upper unconfined aquifer (Vashon Drift). However, mass balance calculations show the existing treatment systems alone will not accomplish the remedial action objective of cleaning up the aquifer to drinking water standards within 30 years as specified in the Record of Decision (ROD). This conclusion is based on the estimated mass of TCE at the source term (51,000 kg), the calculated mass of TCE in the aquifer (4,900 kg), and the removal rate of the pump-and-treat systems that currently ranges from 324 to 667 kg of TCe per year. Four areas within the TCE plume have been identified where enhancements could be made to the existing treatment operations. These ...

1998-07-01

487

Hg2+ reduction and re-emission from simulated wet flue gas desulfurization liquors.  

Science.gov (United States)

In this study, considering that Hg(2+) in wet flue gas desulfurization (FGD) systems can easily be reduced and then released into atmosphere, causing secondary pollution, the researches about Hg(2+) reduction and Hg(0) re-emission mechanism were carried out. The effects of several experimental parameters on the reduction were studied, including initial pH, temperature, and concentrations of Cl(-) and S(IV). Our experimental results indicated that Cl(-) had a restraining effect on the Hg(2+) reduction and Hg(0) re-emission, after 24h reaction, only 20.5% of Hg(2+) was reduced with 100mM Cl(-) in simulated desulfurization solution. Cl(-) can slow Hg(2+) reduction and Hg(0) re-emissions dramatically through changing reaction mechanism, with formation of new intermediate: ClHgSO(3)(-), which can decompose to Hg(0), but much more slowly than Hg(SO(3))(2)(2-) or HgSO(3). Simulating the conditions of the practical application ...

2009-08-03

488

Enzymatic catalysis in cosolvent modified pressurized organic solvents.  

Science.gov (United States)

An important advantage of carrying out enzymatic catalysis in organic media is the increased solubility of hydrophobic substrates. This study compares a model lipase catalyzed esterification of cholesterol using vinyl acetate (VA) in two such nontraditional media: high-pressure hexane and supercritical (SCF) ethane. The effect of using one of the reactants (VA) as a cosolvent to increase the solubility of the other reactant (cholesterol) in SCF ethane has been investigated. The thermodynamic activity of water (a(w)) in the reaction media was controlled by the direct addition of the salt hydrate pair Na(4)P(2)O(7)/Na(4)P(2)O(7).10H(2)O. The a(w) of the salt hydrate system is shown to be a function of pressure and its variation over the pressure range 104-173 bar has been estimated. The initial reaction rate in pressurized hexane was found to vary linearly with the cholesterol concentration. The reaction rate was also a function of pressure-the effect being more ...

1999-11-01

489

Environmental Biosciences Report for Year 3  

Energy Technology Data Exchange (ETDEWEB)

In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally ...

2007-10-31

490

Environmental Biosciences Quarterly Report  

Energy Technology Data Exchange (ETDEWEB)

In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally ...

2007-01-31

491

Environmental Biosciences Program Report for Year 3  

Energy Technology Data Exchange (ETDEWEB)

In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally ...

2007-04-30

492

Environmental Biosciences Program Quarterly Report  

Energy Technology Data Exchange (ETDEWEB)

In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally ...

2008-01-31

493

Environmental Biosciences Program Quarterly Report  

Energy Technology Data Exchange (ETDEWEB)

In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally ...

2007-07-31

494

Carbon dioxide postcombustion capture: a novel screening study of the carbon dioxide absorption performance of 76 amines  

Energy Technology Data Exchange (ETDEWEB)

The significant and rapid reduction of greenhouse gas emissions is recognized as necessary to mitigate the potential climate effects from global warming. The postcombustion capture (PCC) and storage of carbon dioxide (CO{sub 2}) produced from the use of fossil fuels for electricity generation is a key technology needed to achieve these reductions. The most mature technology for CO{sub 2} capture is reversible chemical absorption into an aqueous amine solution. In this study the results from measurements of the CO{sub 2} absorption capacity of aqueous amine solutions for 76 different amines are presented. Measurements were made using both a novel isothermal gravimetric analysis (IGA) method and a traditional absorption apparatus. Seven amines, consisting of one primary, three secondary, and three tertiary amines, were identified as exhibiting outstanding absorption capacities. Most have a number of structural features in common including steric hindrance and ...

2009-08-15

495

Bench-scale Kinetics Study of Mercury Reactions in FGD Liquors  

Energy Technology Data Exchange (ETDEWEB)

This document is the final report for Cooperative Agreement DE-FC26-04NT42314, 'Kinetics Study of Mercury Reactions in FGD Liquors'. The project was co-funded by the U.S. DOE National Energy Technology Laboratory and EPRI. The objective of the project has been to determine the mechanisms and kinetics of the aqueous reactions of mercury absorbed by wet flue gas desulfurization (FGD) systems, and develop a kinetics model to predict mercury reactions in wet FGD systems. The model may be used to determine optimum wet FGD design and operating conditions to maximize mercury capture in wet FGD systems. Initially, a series of bench-top, liquid-phase reactor tests were conducted and mercury species concentrations were measured by UV/visible light spectroscopy to determine reactant and byproduct concentrations over time. Other measurement methods, such as atomic absorption, were used to measure concentrations of vapor-phase elemental mercury, that cannot be ...

2008-03-31

496

An investigation of the origin of the electrochemical hydrogen storage capacities of the ball-milled Co-Si composites  

Energy Technology Data Exchange (ETDEWEB)

The Co-Si composites with a molar ratio of 2:1 are synthesized by ball-milling method and their potential as negative electrode materials of Ni-MH batteries is investigated. The microstructure, morphology and chemical state of the ball-milled Co-Si composites are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). XRD patterns show that the ball-milled samples for 10 and 20 h contain Co, Si and Co{sub 2}Si phases, and the ball-milled samples for 40 and 60 h are mainly amorphous Co{sub 2}Si alloys. In contrast to the high initial discharge capacity (1012 mAh/g) obtained for the sample ball-milled for 10 h, the discharge capacities of the samples ball-milled for 40 and 60 h are very low. It indicates that the hydrogen storage capacity of pure Co{sub 2}Si alloy is very low. It is found that the formation of active Co nanoparticles and Si oxidation are responsible for the high values of the ...

2010-02-15

497

Alternative fuels in diesel engine  

Energy Technology Data Exchange (ETDEWEB)

In this investigation natural gas has been used as an alternative fuel in diesel engines. Experiments have been performed to study the performance of the dual fuel engine with different diesel quantities as pilot injection. It was suggested in this research that combustion in the dual fuel engine occurred in four stages: the delay period, the slow stage of combustion, the rapid stage of combustion and the fourth stage of combustion. Because of the slower flame speed of natural gas and also because of the prolonged delay period, the combustion of the gas-air continued well into the expansion stroke. These resulted in lower efficiency and higher brake specific fuel consumption, and also higher exhaust gas temperature and higher carbon monoxide in the exhaust when the engine ran on dual fuel. The carbon dioxide and black smoke in the exhaust decreased as the gas was introduced in the engine. The ratio of alternative to diesel fuel was varied at the same load also at ...

1991-01-01