WorldWideScience
2

Driving with Hemianopia, II: Lane Position and Steering in a Driving Simulator  

UK PubMed Central (United Kingdom)

Purpose.The hypothesis that drivers with homonymous hemianopia (HH) would take a lane position that increased the safety margin on their blind side was tested with a driving simulator.Methods.Twelve...Full Text Available

2010-12-01

3

The heart and soul of Richard P. Feynman  

CERN Document Server

The heart and soul of Richard P. Feynman

1989-01-01

4

Neal Lane: Confessions of a President's Science Advisor  

ScienceCinema

...policy issues global warming global climate change ? there's a famous hockey ...global warming the greatest hopes for betray them and kind of forgotten ...

5

Heart Valve Replacement  

Medline Plus

X-Plain Heart Valve Replacement Reference Summary Introduction Sometimes people have serious problems with their heart valves. A heart valve repair or ...

6

Road ecology from a road-side assemblage of forest birds in south-western Australia  

Science.gov (United States)

... verges of a two-lane highway in continuous Jarrah Eucalyptus marginata forest of south-western Australia. Midway during this ... Birds were recorded from the beginning of continuous Jarrah Eucalyptus marg...

7

How to charge electric-powered automobiles; Volle Ladung, aber wie?  

Energy Technology Data Exchange (ETDEWEB)

Electric cars can be recharged via charging stations, battery exchange, or induction cable lanes in asphalted roads. The users' wishes remain unexplored, so a number of technologies are competing in this sector.

2011-01-15

10

Energy consumption by the private and commercial vehicles, and by public transport facilities, which comprise urban street traffic; Energiforbrug ved individuel og kollektiv trafik i bygader  

Energy Technology Data Exchange (ETDEWEB)

The aim was to compare the energy consumption by private and commercial vehicles with that of public transport facilities constituting urban street traffic, and to evaluate the influence of various traffic related plans such as green waves (where cars are able to drive through the town with relatively few accelerations and braking) streets with lower speed limits and special lanes and priorities for buses. The traffic pattern in four Copenhagen streets (Jagtvej, Soelvgade, Bredgade and Strandvejen) were measured and analyzed both in, and not in, the rush hour, and a special model was used to calculate the energy consumption. The model defines degree of acceleration and slow-down and speed when calculating energy consumption with regard to various driving patterns. It also calculates carbon dioxide emission. It was found that energy consumption decreased with increasing driving speed at 10-60 km/h for all vehicles. The case of buses is a little different because of ...

1993-03-01

11

Energy consumption by the private and commercial vehicles, and by public transport facilities, which comprise urban street traffic. Energiforbrug ved individuel og kollektiv trafik i bygader  

Energy Technology Data Exchange (ETDEWEB)

The aim was to compare the energy consumption by private and commercial vehicles with that of public transport facilities constituting urban street traffic, and to evaluate the influence of various traffic related plans such as green waves (where cars are able to drive through the town with relatively few accelerations and braking) streets with lower speed limits and special lanes and priorities for buses. The traffic pattern in four Copenhagen streets (Jagtvej, Soelvgade, Bredgade and Strandvejen) were measured and analyzed both in, and not in, the rush hour, and a special model was used to calculate the energy consumption. The model defines degree of acceleration and slow-down and speed when calculating energy consumption with regard to various driving patterns. It also calculates carbon dioxide emission. It was found that energy consumption decreased with increasing driving speed at 10-60 km/h for all vehicles. The case of buses is a little different because of ...

1993-03-01

12

Randomised trial of telephone intervention in chronic heart failure: DIAL trial  

UK PubMed Central (United Kingdom)

Objective To determine whether a centralised telephone intervention reduces the incidence of death or admission for worsening heart failure in outpatients with chronic heart failure.Design...Full Text Available

2005-08-20

13

Hypertrophy and Heart Failure in Mice Overexpressing the Cardiac Sodium-Calcium Exchanger  

UK PubMed Central (United Kingdom)

Background:The cardiac sodium–calcium exchanger (NCX1) is a key sarcolemmal protein for the maintenance of calcium homeostasis in the heart. Since heart failure...Full Text Available

2007-05-01

14

Electrophysiological Remodeling in Heart Failure  

UK PubMed Central (United Kingdom)

Heart failure affects nearly 6 million Americans, with a half-million new cases emerging each year. Whereas up to 50% of heart failure patients die of arrhythmia, the diverse mechanisms underlying...Full Text Available

2010-04-01

15

Cholesterol and Heart Disease: Current Concepts in Pathogenesis and Treatment  

UK PubMed Central (United Kingdom)

One of the modifiable risk factors associated with coronary heart disease (CHD) is hypercholesterolemia. This paper reviews the major plasma lipids and how they relate to coronary heart disease. Among...Full Text Available

1986-08-01

16

Road Interpretation for Driver Assistance Based on an Early Cognitive Vision System  

DEFF Research Database (Denmark)

In this work, we address the problem of road interpretation for driver assistance based on an early cognitive vision system. The structure of a road and the relevant traf?c are interpreted in terms of ego-motion estimation of the car, independently moving objects on the road, lane markers and large scale maps of the road. We make use of temporal and spatial disambiguation mechanisms to increase the reliability of visually extracted 2D and 3D information. This information is then used to interpret the layout of the road by using lane markers that are detected via Bayesian reasoning. We also estimate the ego-motion of the car which is used to create large scale maps of the road and also to detect independently moving objects. Sample results for the presented algorithms are shown on a stereo image sequence, that has been collected from a structured road.

2009-01-01

17

The Heart Failure Epidemic  

UK PubMed Central (United Kingdom)

Heart failure has been singled out as an emerging epidemic, which could be the result of increased incidence and/or increased survival leading to increased prevalence. Knowledge of the responsibility...Full Text Available

2010-04-01

18

Quality and availability of consumer information on heart failure in Australia  

UK PubMed Central (United Kingdom)

BackgroundProvision of consumer information and patient education are considered an essential part of chronic disease management programmes developed for patients with heart failure....Full Text Available

19

OXYGEN UPTAKE, HEART RATE, AND BODY ...  

Science.gov (United States)

... Joint Staff and other US Military (ie, Army, Navy, Air ... HEART RATE, AND BODY TEMPERATURE DURING WORK IN MAN, DOG, AND SWINE. ...

1962-03-01

20

Ion channels, transporters, and pumps as targets for heart failure  

UK PubMed Central (United Kingdom)

Congestive heart failure (CHF) is a leading cause of morbidity and mortality. CHF is marked by atrial and ventricular enlargement and reduced cardiac contractility, as well as an association...Full Text Available

2009-10-01

21

The alkali sorption process by solid sorbents at high temperature  

Energy Technology Data Exchange (ETDEWEB)

The removal of toxic metals and alkalis from gas streams at high temperatures was investigated. This is important for the development of coal-fired combined cycle power generation systems.

2000-03-01

22

High-Temperature Solar Cell Development - GLTRS - NASA  

Science.gov (United States)

High-Temperature Solar Cell Development. Geoffrey A. Landis,. NASA John Glenn Research Center. 21000 Brookpark Road, Cleveland, OH 44135. Danielle ...

23

Beta-21S: A High Temperature Metastable Beta Titanium Alloy ...  

Science.gov (United States)

... Accession Number : ADD144314. Title : Beta-21S: A High Temperature Metastable Beta Titanium Alloy. Descriptive Note : Conference Proceedings, ...

24

[Heart injuries: diagnosis and therapy].  

Science.gov (United States)

The clinical manifestation of wounds of the heart is determined by the mode, site and size of the injury as well as the structure of the pericardial and myocardial lesion. Diagnosis can be confirmed by ECG and echocardiography. Only 20% of the patients with penetrating wounds of the heart live for more than 30 minutes. Pericardio-centesis should be used only to gain time for a safe sternotomy, cardiac decompression and suture of the wound of the heart. An aggressive surgical approach is mandatory. Cardiopulmonary bypass is necessary only to correct of concomitant lesions. PMID:1983618

1990-01-01

25

Chalon/Saint-Marcel manufacturing plant; L'usine de Chalon/Saint-Marcel  

Energy Technology Data Exchange (ETDEWEB)

AREVA is the world leader in the design and construction of nuclear power plants, the manufacture of heavy components, and the supply of nuclear fuel and nuclear services such as maintenance and inspection. The Equipment Division provides the widest range of nuclear components and equipment, manufactured at its two facilities in Jeumont, northern France, and St. Marcel, in Burgundy. The St. Marcel plant, set on 35 ha (87.5 acres) near Chalon-sur-Saone, was established in 1973 in a region with a long history of specialized metalworking and mechanical activities to meet the demand for non-military nuclear requirements in France. The site offers two advantages: - excellent facilities for loading and transporting heavy components on the Saone river, - it's proximity to other group sites. Since its completion in 1975, the Chalon/St. Marcel facility has manufactured all the heavy components for French pressurized water reactors (PWRs) ranging from 900 MW to 1500 MW. It has also ...

2008-07-01

26

Wear resistant of Al{sub 2}O{sub 3}/heat-resistant steel at high temperature  

Energy Technology Data Exchange (ETDEWEB)

The high temperature abrasive wear resistant of the composites with different Al{sub 2}O{sub 3} volume fractions, particle coating and size were investigated and the failure action of composites under different conditions at high temperature was analyzed. The results showed that the high temperature abrasive wear resistant of composite with Ni coating and wide size and 39% volume fraction of particle is the best among all composites examined. (orig.)

2005-07-01

31

Interaction of silicides in the Pd - Mo - Si ternary system  

International Nuclear Information System (INIS)

... chemical reactions high temperature lattice parameters microhardness

33

Coated Superalloys for Power Installations  

International Science & Technology Center (ISTC)

Characterization and Testing of Coated Nickel- and Iron-Based Superalloys for Application in High-Temperature Power Installations

34

Ceramic Composite Materials  

International Science & Technology Center (ISTC)

Development of Ceramic Composite Materials and Structural Elements for High-Temperature Nuclear Reactors

35

Simulation of traffic flow and control using conventional, fuzzy, and adaptive methods  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the graphical simulation of a traffic environment. The environment includes streets leading to an intersection, the intersection, vehicle traffic, and signal lights in the intersection controlled by different methods. The simulation allows for the study of parameters affecting traffic environments and the study of different control strategies for traffic signal lights, including conventional, fuzzy, and adaptive control methods. Realistic traffic environments are simulated including a cross intersection, with one or more lanes of traffic in each direction, with and without turn lanes. Vehicle traffic patterns are a mixture of cars going straight and making right or left turns. The free velocities of vehicles follow a normal distribution with a mean of the ``posted`` speed limit. Actual velocities depend on such factors as the proximity and velocity of surrounding traffic, approaches to intersections, and human response ...

1992-06-01

36

What are the sources of hydrogen peroxide production by heart mitochondria?  

UK PubMed Central (United Kingdom)

Coupled rat heart mitochondria produce externally hydrogen peroxide at the rates which correspond to about 0.8 and 0.3 per cent of the total oxygen consumption at State 4 with succinate and...Full Text Available

2010-01-01

37

The zebrafish heart regenerates after cryoinjury-induced myocardial infarction  

UK PubMed Central (United Kingdom)

BackgroundIn humans, myocardial infarction is characterized by irreversible loss of heart tissue, which becomes replaced with a fibrous scar. By contrast, teleost fish and urodele...Full Text Available

38

The effect of swimming exercise on spontaneous ventricular defibrillation and ventricular fibrillation threshold in the isolated perfused rat heart.  

Science.gov (United States)

Effects of swimming exercise training on left ventricular contraction and relaxation, the incidence of spontaneous defibrillation and the ventricular fibrillation threshold were studied in the isolated, perfused rat heart. The heart/body weight ratio was 4.8 +/- 0.4 x 10(-3) in swimmers compared with 3.9 +/- 0.6 x 10(-3) in sedentary controls (p less than 0.0005). The spontaneous heart rate was lower in isolated hearts of trained animals (222 +/- 18 bpm compared with 244 +/- 28, p less than 0.05). Left ventricular systolic pressure was higher in trained hearts and the rate of ventricular relaxation enhanced (p less than 0.05). The ventricular fibrillation threshold was 7.2 +/- 5.2 and 10.8 +/- 6.1 mamp in hearts of swimmers and controls, respectively, the difference not being significant. The incidence of spontaneous defibrillation was not significantly ...

1990-12-01

39

The causes, consequences, and treatment of left or right heart failure  

UK PubMed Central (United Kingdom)

Chronic heart failure (HF) is a cardiovascular disease of cardinal importance because of several factors: a) an increasing occurrence due to the aging of the population, primary and secondary prevention...Full Text Available

2011-01-01

40

The Association of Alcohol and Alcohol Metabolizing Gene Variants with Diabetes and Coronary Heart Disease Risk Factors in a White Population  

UK PubMed Central (United Kingdom)

BackgroundEpidemiological studies have shown a J- or U-shaped relation between alcohol and type 2 diabetes and coronary heart disease (CHD). The underlying mechanisms are not clear....Full Text Available

41

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

42

Status of rheumatic heart disease in rural Pakistan  

UK PubMed Central (United Kingdom)

Objectives: To determine the community based prevalence of rheumatic heart disease (RHD) in the rural population of the district of Rahim Yaar Khan in Pakistan.Subjects...Full Text Available

2004-04-01

43

Radionuclide angiocardiography in the diagnosis of congenital heart disorders.  

UK PubMed Central (United Kingdom)

Radionuclide angiocardiography provides a noninvasive assessment of cardiac function and blood flow through the heart and lungs. During the past three years, this procedure has been used at the Duke...Full Text Available

1981-06-01

44

Protective effects of hydroalcoholic extract from rhizomes of Cynodon dactylon (L.) Pers. on compensated right heart failure in rats  

UK PubMed Central (United Kingdom)

BackgroundThe rhizomes of Cynodon dactylon are used for the treatment of heart failure in folk medicine. In the present study, we investigated the effects of hydroalcoholic...Full Text Available

45

Prevention and treatment of functional and structural radiation injury in the rat heart by pentoxifylline and alpha-tocopherol  

UK PubMed Central (United Kingdom)

PurposeRadiation-induced heart disease (RIHD) is a severe side effect of thoracic radiotherapy. This study examined the effects of PTX and α-tocopherol on...Full Text Available

2008-09-01

46

Physique and Serum Lipids of Young London Busmen in relation to Ischaemic Heart Disease  

UK PubMed Central (United Kingdom)

Earlier studies of white London busmen revealed that the ischaemic heart disease experience of conductors is better than that of drivers. Various factors which might be related to this difference have...Full Text Available

1967-07-01

47

Pharmacokinetics of multiple doses of valsartan in patients with heart failure.  

Science.gov (United States)

Angiotensin II has adverse actions in heart failure including vasoconstriction, aldosterone secretion, and activation of the sympathetic nervous system. Valsartan, a potent specific angiotensin II type 1 receptor blocker, may produce beneficial effects in heart failure. The purpose of this study was to evaluate the steady-state pharmacokinetics of valsartan 40, 80, and 160 mg each given every 12 h for 7 days in heart failure patients. Eighteen patients with chronic stable heart failure and left ventricular ejection fractions power model, showed that doubling the dose increased the AUC and Cmax 1.8 times. The pharmacokinetics of valsartan are predictable in heart failure patients within the dose range of 40-160 mg BID. Age did not appear to have influenced the valsartan clearance in heart failure patients. The pharmacokinetic values were higher in ...

2002-11-01

48

NASA - NASA COMPUTER ROCKET SCIENCE HELPS DEBAKEY HEART PUMP TEAM  

Science.gov (United States)

Feb 24, 2000 ... NASA computer experts have been using a supercomputer to improve the NASA/ DeBakey miniature heart assist pump, leading to on-going human ...

49

Matching ATP Supply and Demand in Mammalian Heart: In Vivo, In Vitro and In Silico Perspectives  

UK PubMed Central (United Kingdom)

Although the heart rapidly adapts cardiac output to match the body’s circulatory demands, the regulatory mechanisms ensuring that sufficient ATP is available to perform the required...Full Text Available

2010-02-01

50

Massachusetts' approach to the prevention of heart disease, cancer, and stroke.  

UK PubMed Central (United Kingdom)

Heart disease, cancer, and cerebrovascular disease together cause more than two out of three deaths in the United States annually. These three diseases are largely a result of widespread risk factors...Full Text Available

1986-01-01

51

Layered Functional Network Analysis of Gene Expression in Human Heart Failure  

UK PubMed Central (United Kingdom)

BackgroundAlthough dilated cardiomyopathy (DCM) is a leading cause of heart failure (HF), the mechanism underlying DCM is not well understood. Previously, it has been demonstrated...Full Text Available

52

Investigating the spatial variability in incidence of coronary heart disease in the Gazel cohort: the impact of area socioeconomic position and mediating role of risk factors  

UK PubMed Central (United Kingdom)

Study objectiveThe study aim was to improve our understanding of the relationships between contextual socioeconomic characteristics and coronary heart disease (CHD)...Full Text Available

2011-02-01

53

In vivo imaging of neutrotransmitter functions in brain, heart and tumors  

Energy Technology Data Exchange (ETDEWEB)

This volume contains the proceedings of a symposium entitled In Vivo Imaging of Neurotransmitter Function in Brain, Heart, and Tumors'' held August 24--25, 1990 in Montreal Canada. The six individual papers contained herein are separately abstracted and indexed for the database.

1991-01-01

54

Exercise training for systolic heart failure: Cochrane systematic review and meta-analysis  

UK PubMed Central (United Kingdom)

AimsTo determine the effect of exercise training on clinical events and health-related quality of life (HRQoL) of patients with systolic heart failure.Methods...Full Text Available

2010-07-01

55

Does amiodarone affect heart rate by inhibiting the intracellular generation of triiodothyronine from thyroxine?  

UK PubMed Central (United Kingdom)

The hypothesis that the antiarrhythmic drug amiodarone slows down the heart rate by its inhibitory action on the intracellular conversion of thyroxine (T4) to 3,5,3' triiodothyronine (T3) was investigated....Full Text Available

1984-05-01

56

Consequences of unlocking the cardiac myosin molecule in human myocarditis and cardiomyopathies  

UK PubMed Central (United Kingdom)

Myocarditis, often initiated by viral infection, may progress to autoimmune inflammatory heart disease, dilated cardiomyopathy and heart failure. Although cardiac myosin is a dominant autoantigen...Full Text Available

2008-09-01

57

Anger Expression and Risk of Coronary Heart Disease: Evidence From the Nova Scotia Health Survey  

UK PubMed Central (United Kingdom)

BackgroundWhile some studies have found that anger increases the risk of incident coronary heart disease (CHD), others found anger protective. Prior studies did not...Full Text Available

2010-02-01

58

Traffic flow theory and traffic flow simulation models. Transportation research record  

Energy Technology Data Exchange (ETDEWEB)

;Contents: Comparison of Simulation Modules of TRANSYT and INTEGRATION Models; Evaluation of SCATSIM-RTA Adaptive Traffic Network Simulation Model; Comparison NETSIM, NETFLO I, and NETFLO II Traffic Simulation Models for Fixed-Time Signal Control; Traffic Flow Simulation Through Parallel Processing; Cluster Analysis as Tool in Traffic Engineering; Traffic Platoon Dispersion Modeling on Arterial Streets; Hybrid Model for Estimating Permitted Left-Turn Saturations Flow Rate; and Passing Sight Distance and Overtaking Dilemma on Two-Lane Roads.

1996-12-31

59

Healthy Heart Handbook for Women  

Science.gov (United States)

... are old enough, teach them to use the cooktop, oven, microwave, and toaster safely. Show teens how ...

60

Traffic flow optimization on rural networks  

Energy Technology Data Exchange (ETDEWEB)

Seasonal traffic on intercity corridors often creates severe congestion at various bottlenecks, such as land-drops and drawbridges. A Traffic Simulation And Optimization model (TSAO) has been developed in order to 1) evaluate traffic impacts (including travel time, vehicle operating costs, accidents, air pollution and fuel consumption) of a given routing pattern on a network, and 2) determine the optimal flow pattern. In its latest version, the TSAO model uses: 1) a macroscopic simulation approach to trace vehicle platoons through a network; 2) Greenshield's equation to represent volume-speed relationship on freeways and multi-lane highways, and Highway Capacity Manual method for two-lane rural highways; 3) Lighthill's shockwave function to simulate queue propagation; 4) event-scan time management for simulation; 5) variable link capacity for two-lane rural highways or to stimulate incidents; 6) AASHTO ...

1983-01-01

61

Steam generator access modification and waterlance cleaning for Wolsong and other nuclear plants  

International Nuclear Information System (INIS)

Steam generators for nuclear plants require access to the primary and secondary side for various inspection, cleaning and repair procedures and upon achieving access various inspection and cleaning tasks must be carried out. Steam generators currently at manufacture are therefore provided with; primary side access via the primary manways, steam drum access via the steam drum manway, U-bend region access via the secondary manway and drum-internals access passages, tubesheet secondary side access via tubesheet level inspection ports and tube support plate access via tube support level access ports. Many CANDU steam generators were built with only primary and drum manways and either no tubesheet ports or ports which were located ineffectively. The steam generators at Wolsong 1 were built with secondary side inspection ports that provided only limited access away from the no-tube-lane. In addition they have very difficult internal no-tube-lane ...

2002-05-05

62

Novel Biomarkers in Acute Heart Failure  

British Library Electronic Table of Contents (United Kingdom)

Heart failure goes beyond mechanical dysfunction and involves an interplay of multiple pathophysiologic mechanisms, including inflammation, tissue remodeling, neurohormonal and endocrine signaling, and interactions with the renal and nervous systems. This article highlights some novel biomarkers that may aid in diagnosis, treatment, and prognosis of acute heart failure, specifically focusing on ST2, endoglin, galectin-3, cystatin C, neutrophil gelatinase?associated lipocalin, midregional pro-adrenomedullin, chromogranin A, adiponectin, resistin, and leptin and their emerging clinical roles.

2011-01-01

63

Liver function abnormalities and outcome in patients with chronic heart failure: data from the Candesartan in Heart Failure: Assessment of Reduction in Mortality and Morbidity (CHARM) program  

UK PubMed Central (United Kingdom)

AimsThe prevalence and importance of liver function test (LFT) abnormalities in a large contemporary cohort of heart failure patients have not been systematically evaluated.Full Text Available

2009-02-01

64

Mass spectrometric characterization of high-temperature outgassing of anisotropic pyrolytic boron nitride  

International Nuclear Information System (INIS)

This paper describes a system for fast mass spectrometric characterization of high-temperature outgassing measurements and measuring the total quantity of gas evolved for boron nitride. 2 references, 1 figure, 2 tables.

65

Designer himself throws light upon high-temperature reactor  

Energy Technology Data Exchange (ETDEWEB)

THe high-temperature reactor is one of the alternatives for the now predominantly employed water-reactors. In a recently published book designer Rudolf Schulten outlines his concept. In this article the book is reviewed. (author). 1 ref.; 1 fig.

1990-04-01

66

Designer himself throws light upon high-temperature reactor  

International Nuclear Information System (INIS)

THe high-temperature reactor is one of the alternatives for the now predominantly employed water-reactors. In a recently published book designer Rudolf Schulten outlines his concept. In this article the book is reviewed. (author). 1 ref.; 1 fig.

67

Altering high temperature subterranean formation permeability  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a delayed acrylamide containing polymer crosslinker having stability in an aqueous solution at high temperatures. It comprises: a combination of an aldehyde and a salicylic acid derivative selected from salicylamide and acetysalicylic acid.

1991-02-19

68

The effects of high-temperature exposure on the properties of heat-resistant alloys  

Energy Technology Data Exchange (ETDEWEB)

The exposure of heat-resistant alloys to high temperature can significantly change their mechanical properties. This paper presents and analyzes data on the effect of thermal exposure on the tensile and impact behavior of three cast materials -- the HK-40, HP-50, and 21Cr-32Ni-Fe alloys -- and of wrought material -- Alloy 800. The changes in tensile and impact properties caused by high-temperature exposure are reviewed. Reasons for these property changes and needs for considering them in the design, operation, and life assessment of high-temperature equipment are discussed.

1994-12-31

69

Self-Propagating High-Temperature Synthesis Technologies  

International Science & Technology Center (ISTC)

Development of SHS-technologies for SiC, Si3N4 and Ceramic Composites on Their Basis from Rocks

70

Ductile aluminide alloys for high temperature applications  

Energy Technology Data Exchange (ETDEWEB)

Alloys are described which contain nickel, aluminum, boron, iron and in some instances manganese, niobium and titanium.

1987-01-01

71

Damage and Repair of the APS Graphite/Epoxy Composite ...  

Science.gov (United States)

... Abstract : High temperature testing of graphite/epoxy laminates and composite sandwich panels was performed while the Shuttle was on orbit to ...

1982-10-12

72

Heart rate correction models to detect QT interval prolongation in novel pharmaceutical development  

British Library Electronic Table of Contents (United Kingdom)

Introduction: The QT interval of the electrocardiogram (ECG) reflects the duration of ventricular depolarization and repolarization. A drug-induced prolongation of ventricular repolarization, and thereby QT prolongation, is recognized to be a marker for an enhanced risk for ventricular arrhythmia. The assessment of a drug's effect on the QT interval has therefore become routine within pharmaceutical research and development. However, the heart rate has a major influence on the QT interval; the QT interval shortens as heart rate increases such that one needs to account for such heart rate-dependent changes when evaluating possible drug-induced effects on the QT interval. The relationship between the QT interval and heart rate can be modeled mathematically and using this function a so-called...

2011-01-01

73

High-temperature superconductivity (HTS): summary of case study results; Vorteile der Hochtemperatursupraleitung. Resultate von Fallstudie  

Energy Technology Data Exchange (ETDEWEB)

The system study 'High Temperature Superconductivity (HTS) in power systems' lists the technical and economical advantages for power generation, transmission and distribution systems using components made of HTS material as seen in the light of current knowledge in the superconductivity area. This report lists the advantages of using high-temperature superconductivity in the power industry area and summarises the results obtained in various case studies on the subject.

2000-07-01

74

High-temperature ceramic receivers  

Energy Technology Data Exchange (ETDEWEB)

An advanced ceramic dome cavity receiver is discussed which heats pressurized gas to temperatures above 1800/sup 0/F (1000/sup 0/C) for use in solar Brayton power systems of the dispersed receiver/dish or central receiver type. Optical, heat transfer, structural, and ceramic material design aspects of the receiver are reported and the development and experimental demonstration of a high-temperature seal between the pressurized gas and the high-temperature silicon carbide dome material is described.

1980-01-01

75

Heat transfer problems in high temperature heat exchangers  

International Nuclear Information System (INIS)

This paper deals with construction types of high temperature heat exchangers, their circulation loops and temperature differences. Most attention is given to gas dynamics, convective heat transfer, convection and radiant heat transfer interaction in high temperature heat exchangers. The ways of heat transfer augmentation and efficient heat exchanger construction are discussed.

1986-01-01

76

General corrosion of ALLOY 800 in high temperature water and its prevention  

Energy Technology Data Exchange (ETDEWEB)

General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).

1989-10-01

77

General corrosion of ALLOY 800 in high temperature water and its prevention  

International Nuclear Information System (INIS)

General corrosion behavior of ALLOY 800 in high temperature water was studied in relation to its surface film structure. The surface film formed in water was found to decrease the corrosion rate of ALLOY 800. This film is composed of Ni ferrite, and can be obtained by oxidation in air or steam. Based on these results, air or steam oxidation treatment to inhibit Ni and Co release of ALLOY 800 into high temperature water is proposed. (author).

78

Relationships of valve histology and mitochondrial and myofibril volume densities to hypertrophy of copper-deficient rat hearts  

Energy Technology Data Exchange (ETDEWEB)

Twenty-four male weanling rats were fed either copper-adequate or -deficient diets until 9 or 11 weeks of age. Deficient rat hearts had increased mitochondria: myofibril compared to adequate rats. Eleven week old deficient rat hearts had decreased mitochondria: myofibril as the hearts increased in weight, but the larger hearts had greater myofibril volume densities. Cardiac mitochondria of deficient rats appeared vacuolated with fragmented cristae and translucent matrix. Valves from copper deficient rats appeared to have less connective tissue and were fragmented in areas. For deficient rats, heart:body weights of 9 wk old rats were negatively correlated with bicuspid valve pathology scores, whereas tricuspid valve scores from 11 wk old rats were negatively correlated with myofibril volume densities. These data suggest that the enlargement of the copper-deficient rat ...

1991-03-15

79

Quantification of the local glucose utilization and local blood flow in the heart of the awake rat using the /sup 14/C-2-deoxyglucose and /sup 14/C-iodoantipyrine methods  

Science.gov (United States)

Local cardiac glucose utilization (LCarGU) was quantified in the rat heart according to the Sokoloff model and local cardiac blood flow (LCarBF) according to the /sup 14/C-iodoantipyrine method. For quantitative autoradiography calibration curves for heart slices were performed. They differed from the brain calibration curves by 8%. The lumped constant was 0.377 in isolated working hearts. LCarGU and LCarBF could then be quantified in awake rats. At different locations mean LCarGU of different hearts varied from 85 to 200 ..mu..moles/100g/min and mean LCarBF from 390 to 831 ml/100g/min. The ratio subendocardial/subepicardial glucose utilization or blood flow was not systematically different from 1. The results indicate that glucose can be an important fuel in the heart of the awake rat, although its contribution to overall metabolism varies from animal to animal.

1986-03-05

80

Models of cardiac electromechanics based on individual hearts imaging data  

British Library Electronic Table of Contents (United Kingdom)

Current multi-scale computational models of ventricular electromechanics describe the full process of cardiac contraction on both the micro- and macro- scales including: the depolarization of cardiac cells, the release of calcium from intracellular stores, tension generation by cardiac myofilaments, and mechanical contraction of the whole heart. Such models are used to reveal basic mechanisms of cardiac contraction as well as the mechanisms of cardiac dysfunction in disease conditions. In this paper, we present a methodology to construct finite element electromechanical models of ventricular contraction with anatomically accurate ventricular geometry based on magnetic resonance and diffusion tensor magnetic resonance imaging of the heart. The electromechanical model couples detailed repres...

2011-01-01

81

Cooperative use of unmanned sea surface and micro aerial vehicles at Hurricane Wilma  

British Library Electronic Table of Contents (United Kingdom)

On Oct. 24, 2005, Hurricane Wilma, a category 5 storm, made landfall at Cape Romano, Florida. Three days later, the Center for Robot-Assisted Search and Rescue at the University of South Florida deployed an iSENYS helicopter and a prototype unmanned water surface vehicle, AEOS-1, to survey damage in parts of Marco Island, 14 km from landfall. The effort was the first known use of unmanned sea surface vehicles (USVs) for emergency response and established their suitability for the recovery phase of disaster management by detecting damage to seawalls and piers, locating submerged debris (moorings and handrails), and determining safe lanes for sea navigation. It provides a preliminary domain theory of postdisaster port and littoral inspection with unmanned vehicles for use by the human-robot ...

2008-01-01

82

A Hundred Years of Physics on Show  

CERN Multimedia

The New Yorker Richard Feynman, well known to all physicists for his diagrams. Eleven vivid posters have recently been hung along the Theoretical Physics corridor on the first floor of Building 53. They tell the story of a century of physics, between 1900 and the end of the nineteen-nineties, the century that gave us atomic and quantum physics and the great breakthroughs that have rocked our understanding of the world and the universe. The posters are a gift from the American Physical Society to the CERN Library. As they were designed for high school and university book collections in the US, they necessarily have a somewhat American view of the history of science. But it is still instructive to revisit contemporary physics through its great figures, such as Marie Curie, Stephen Hawking, and Richard Feynman, not to mention Albert Einstein and many others. Why not take the time for a little trip down this particular stretch of Memory Lane?

2002-01-01

83

Uncorrelated Randomness of the Heart Rate Is Associated with Sepsis in Sick Premature Infants  

UK PubMed Central (United Kingdom)

BackgroundLate-onset sepsis in the premature infant is frequently revealed by severe, unusual and recurrent bradycardias. In view of the high morbidity and mortality...Full Text Available

2009-03-01

84

The pros and cons of phytoestrogens  

UK PubMed Central (United Kingdom)

Phytoestrogens are plant derived compounds found in a wide variety of foods, most notably soy. A litany of health benefits including a lowered risk of osteoporosis, heart disease, breast cancer,...Full Text Available

2010-10-01

85

The Mitoscriptome in Aging and Disease  

UK PubMed Central (United Kingdom)

Mitochondria are the major sites where energy is produced in the cell. Functions of organs such as the heart which has high energy demand are seriously affected by dysfunction of mitochondria....Full Text Available

2011-04-19

86

Phospholemman: A Novel Cardiac Stress Protein  

UK PubMed Central (United Kingdom)

Phospholemman (PLM), a member of the FXYD family of regulators of ion transport, is a major sarcolemmal substrate for protein kinases A and C in cardiac and skeletal muscle. In the heart, PLM...Full Text Available

2010-08-01

87

Myocardial pharmacokinetics of ebastine, a substrate for cytochrome P450 2J, in rat isolated heart  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE It is well established that cytochrome P450 2J (CYP2J) enzymes are expressed preferentially in the heart, and that ebastine is a substrate for CYP2J, but it is not known whether ebastine is metabolized in myocardium. Therefore, we investigated its pharmacokinetics in the rat isolated perfused heart. EXPERIMENTAL APPROACH Rat isolated hearts were perfused in the recirculating mode with ebastine for 130-min. The concentrations of ebastine and its metabolites, hydroxyebastine and carebastine, were measured using liquid chromatography with a tandem mass spectrometry. The data were analysed by a compartmental model. The time course of negative inotropic response was linked to ebastine concentration to determine the concentration-effect relationship. KEY RESULTS Ebastine w...

2011-01-01

88

FoxO, Autophagy, and Cardiac Remodeling  

UK PubMed Central (United Kingdom)

In response to changes in workload, the heart grows or shrinks. Indeed, the myocardium is capable of robust and rapid structural remodeling. In the setting of normal, physiological demand, the...Full Text Available

2010-08-01

91

APOD: October 19, 1997 - The Heart Of NGC 4261  

Science.gov (United States)

creating such active galactic nuclei as quasars. Strangely, the center of this fiery whirlpool is offset from the exact center of the galaxy - for a reason that for now remains an...

2011-10-07

92

Elevated temperature mechanical properties of fire resistant steel for building structural use. Kenchiku kozoyo taika kozai no koon kyodo tokusei  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the test results on high-temperature strength properties of fire resistant steel(FR steel) for building, the formulation, and the examples of application to member tests and actual buildings. Because of its components and manufacturing method, FR steel excels in strength at elevated temperature due to precipitation and dispersion strengthening. Tests on high temperature properties of FR steel showed that every property such as strength, stress-strain curve, elastic modulus, and creep performance at high temperature was superior to those of conventional steels. Then, it was confirmed in the tensile tests at room temperature and high temperature after heat history that FR steel could be reused after fire. It was also found in the member tests that columns and beams of FR steel could support loadings equivalent to long-term ...

1991-09-30

93

High temperature crystalline superconductors from crystallized glasses  

Energy Technology Data Exchange (ETDEWEB)

A method of preparing a high temperature superconductor from an amorphous phase. The method involves preparing a starting material of a composition of Bi.sub.2 Sr.sub.2 Ca.sub.3 Cu.sub.4 Ox or Bi.sub.2 Sr.sub.2 Ca.sub.4 Cu.sub.5 Ox, forming an amorphous phase of the composition and heat treating the amorphous phase for particular time and temperature ranges to achieve a single phase high temperature superconductor.

1992-01-01

94

Corrosion resistance of oxide scale formed on SiSiC in boiling sulfuric acid  

International Nuclear Information System (INIS)

SiSiC is one of selected materials for the thermal chemical hydrogen production IS (Iodine-Sulfur) process at JAERI. SiSiC was tested in boiling sulfuric acid for 1000 hours. The obtained results showed the following facts. The transverse strength was not changed by sulfuric corrosion, high temperature oxidation and oxidation. Silica scale formed on SiSiC by sulfate corrosion and high temperature oxidation had corrosion resistance in boiling sulfuric acid. Bilayer structure of silica scale produced by high temperature oxidation was not affected by sulfate corrosion. (S.Y.).

95

Trade Study and Design of a TRL-4, 100 degree C, 28- to 600 ...  

Science.gov (United States)

... The LVS bulk capacitance can be implemented using high temperature aluminum electrolytic capacitors with relatively low component volume. ...

2011-01-01

97

The formation and degradation of Ti-Ag and Ti-Pd-Ag solar cell contacts  

Science.gov (United States)

Ti-Ag and Ti-Pd-Ag solar cell contacts structure and degradation dependence on high temperature and humidity environmental exposure

1970-01-01

98

Study on the structural evolution of modified phenol-formaldehyde resin adhesive for the high-temperature bonding of graphite  

International Nuclear Information System (INIS)

A novel adhesive for carbon materials composed of phenol-formaldehyde resin, boron carbide and fumed silica, was prepared. The adhesive property of graphite joints bonded by the above adhesive treated at high-temperatures was tested. Results showed that the adhesive was found to have outstanding high-temperature bonding properties for graphite. The adhesive structure was dense and uniform even after the graphite joints were heat-treated at 1500 deg. C. Bonding strength was 17.1 MPa. The evolution of adhesive structure was investigated. The results indicated that the addition of the secondary additive, fumed silica, improved the bonding performance greatly. Borosilicate phase with better stability was formed during the heat-treatment process, and the volume shrinkage was restrained effectively, which was responsible for the satisfactory high-temperature bonding performance of graphite.

2006-01-01

102

Molten Boron Phase-Change Thermal Energy Storage ...  

Science.gov (United States)

... Advanced thermal storage systems based on very high temperature solid materials such as boron carbide or graphite have been investigated for ...

2011-06-01

103

Metallurgical instabilities during the high temperature low cycle fatigue of nickel-base superalloys  

Energy Technology Data Exchange (ETDEWEB)

In this letter, examples of microstructural instabilities that can significantly affect the low crystal fatigue (LCF) life are pointed out.

1983-01-01

104

High Temperature Superconducting Compounds  

Science.gov (United States)

... Voltage noise power spectral density measurements as a function of temperature, frequency, current, and magnetic field on DyBa2Cu3O7.x (DBCO ...

1992-11-30

105

Gordon Research Conference on High Temperature ...  

Science.gov (United States)

... (Argonne Nat. Lab., Speaker: M. Rand (AERE Harwell, UK) ... 19 - Discussion Leader: P. Potter (AERE Harwell, UK) Speaker: YA Chang (Univ. ...

1984-12-03

108

Corrosion behavior of iron and nickel base alloys in high temperature and pressure water  

International Nuclear Information System (INIS)

In equipment industries, the equipments handling industrial water and pure water are numerous. In power generation including nuclear power generation, water serves as a working medium. Review is made on the experiences in the corrosion of iron and nickel base alloys in high temperature, high pressure water and the results of researches derived from them. Under high temperature and high pressure, carbon steel, low alloy steel, stainless steel and high nickel alloy cause corrosion even in pure water. But in the case of serious corrosion, chlorine, oxygen, alkali and others in water take part. The following matters are described: corrosion by steam; stress corrosion cracking in pure water; corrosion by impurities in high temperature, high pressure pure water, i.e. chlorine ions, dissolved oxygen, and alkali; corrosion under radiation. (J.P.N.).

109

Right-sided invasive metastatic thymoma of the heart  

British Library Electronic Table of Contents (United Kingdom)

Cardiac tumours may display diverse symptoms through potential involvement of any structure of the heart. We describe a case of a highly malignant thymoma with involvement of different cardiac structures with important haemodynamic compromise. With the high sensitivity of transthoracic echocardiography for detection of intracardiac masses, computed tomography and magnetic resonance add essential structural preoperative information on the tumour and surrounding tissue as vessels, pleura, lung and mediastinum.

2011-01-01

110

Particulate air pollution and chronic ischemic heart disease in the eastern United States: a county level ecological study using satellite aerosol data  

UK PubMed Central (United Kingdom)

BackgroundThere are several known factors that cause ischemic heart disease. However, the part played by air pollution still remains something of a mystery. Recent attention has...Full Text Available

111

Blood EPA and DHA Independently Predict All-Cause Mortality in Patients with Stable Coronary Heart Disease. The Heart and Soul Study  

UK PubMed Central (United Kingdom)

BackgroundOmega-3 fatty acid (n-3 FA) blood levels and intakes have been inversely associated with risk for sudden cardiac death, but their relationship with all-cause...Full Text Available

2010-07-01

112

Technology for enhancing chest auscultation in clinical simulation.  

Science.gov (United States)

The ability to use an acoustic stethoscope to detect lung and/or heart sounds, and then to then communicate one's interpretation of those sounds is an essential skill for many medical professionals. Interpretation of lung and heart sounds, in the context of history and other examination findings, often aids the differential diagnosis. Bedside assessment of changing auscultation findings may also guide treatment. Learning lung and heart auscultation skills typically involves listening to pre-recorded normal and adventitious sounds, often followed by laboratory instruction to guide stethoscope placement, and finally correlating the sounds with the associated pathophysiology and pathology. Recently, medical simulation has become an important tool for teaching prior to clinical practice, and for evaluating bedside auscultation skills. When simulating cardiovascular or pulmonary problems, high-quality lung and ...

2011-02-11

113

MRI of congenital heart disease in childhood  

International Nuclear Information System (INIS)

MRI provides a non-invasive diagnostic tool complementing echocardiography on one hand, and showing advantages over echocardiography, on the other hand, especially after corrective procedures. The multiple different MRI sequences need to be adapted to examinations of children and patients with congenital heart disease (CHD), and can be used to detect morphologic changes, blood-flow in the heart and thoracic vessels and diastolic or systolic function of myocardium. Several factors determine the success of the examination of a complex congenital heart disease or a postoperative situs. Pediatric radiologists and radiologists experienced in congenital heart diseases have to work in close cooperation. Echocardiography should be performed before MRI. The results of prior examinations and the clinical history of the patients, including possible palliative or reconstructive operations, must be available before ...

2004-02-01

114

Use of alkali nitrate molten salts as electrolytes in intermediate temperature lithium batteries  

Energy Technology Data Exchange (ETDEWEB)

Advanced lithium batteries presently under development operate either at the high temperatures associated with the LiCl-KCl molten salt (350-450/degree/C), or at ambient temperatures employing organic solvent based electrolytes. An intermediate temperature lithium battery is proposed as an alternative if it reduces corrosion problems present at high temperatures and improved kinetic performance with respect to ambient temperature cells. 17 refs.

1981-01-01

115

The high-temperature reactor's attractiveness lies in passive safety  

International Nuclear Information System (INIS)

In the recent years the use of nuclear energy has turned from a technical and scientific issue to a political one. The high-temperature reactor (HTR) however, has always been advertised as particularly safe. The present situation and future developments of HTR-technology were the two issues that VDI-News brought up on the 27th October on an HTR-conference in an interview with the 'spiritual father' of the HTR, Prof. Dr. Rudolf Schulten of the Juelich Nuclear Research Centre. (orig.).

116

Review of the corrosion resistance properties of Alloy 800 in high-temperature steam  

International Nuclear Information System (INIS)

The investigations carried out on Alloy 800 in aqueous high-temperature environments in France as well as in other countries are reviewed. These studies are mainly concerned with nuclear industry where Alloy 800 can be used as structural material for steam generators of PWR, breeders or HTR. As results referred to in the literature on cracking in caustic environmens do not always agree, a discussion is presented on the matter. The behaviour of Alloy 800 in superheated steam is examined. (Auth.).

117

Mild acidic pretreatment to enhance low severity coal liquefaction promoted by cyclic olefins. Quarterly report, July 1995--September 1995  

Energy Technology Data Exchange (ETDEWEB)

Research continued on low severity coal liquefaction. Research using high temperature infrared of cyclic olefins progressed well during this quarter. Several fluorinated solvents were found that provide a high temperature medium for isotetralin and its aromatic and aliphatic analogues.

1996-03-01

118

Microstructural modifications and high-temperature strength of monocrystalline nickel-base superalloys  

Energy Technology Data Exchange (ETDEWEB)

The examples discussed demonstrate that in order to improve further the high-temperature strength properties of (monocrystalline) nickel-base superalloys, it is expedient to follow two parallel routes, namely alloy development, on the one hand, and suitable modifications of the microstructure by appropriate thermal and mechanical treatments, on the other hand. (orig.)

2000-07-01

119

Magnetic properties of FeSi with cobalt impurities  

Energy Technology Data Exchange (ETDEWEB)

Results of experimental researches of impurity level crystals Fe1-xCoxSi are presented in this article. Magnetic properties in a temperature range up to T {<=} 1000 K are analyzed. It was established that with Co impurities increasing origin of magnetic ordering exists at low temperatures. At high temperatures a high temperature maximum of susceptibility of nominally pure iron monosilicide crystal is observed.

2010-01-01

120

Investigation into superplasticity of Be alloys  

International Nuclear Information System (INIS)

Investigated are the characteristics of high-temperature plastic deformation the velocity sensitivity of flow stresses, deformation curves, flow stresses, deformation before rupture - as well as the structure of beryllium alloys containing nickel (0.5-4 %), yttrium (0.5-2 %) and aluminium (38 %). The alloys containing nickel (2%) and yttrium (0.5 %) are superplastic, however, deformation before fracture of the alloys is lower than that of the unalloyed beryllium. The singularities of high-temperature plastic flow of the alloys and the causes of deterioration of their plasticity are determined.

121

High temperature heat transfer augmentation  

International Nuclear Information System (INIS)

The heat transfer augmentation is reviewed in view of high temperature heat exchangers illuminating the contribution of radiative heat transfer. A number of means and/or devices are presented as well as the sophisticated concept which will be promoted to the extended applications in matured industries such as iron and steel, oir refinery, petro-chemical. It should be emphasized that the more creative and innovatory technology has to be promoted in order to stimulate and refresh the foregoing industries, recognizing the increasing importance of the energy resources.

1985-08-01

122

Fifty successful years of the Institute of Plasma Physics, Academy of Sciences of the Czech Republic  

International Nuclear Information System (INIS)

The history of the Czech Institute of Plasma Physics is highlighted. The article is structured as follows: Cyclic accelerators; Interaction of an external high-frequency field and high-temperature plasma - the tokamak; Interaction of an external high-frequency field and high-temperature plasma - pulse plasma systems; Low-temperature plasma - plasma technologies and new materials; Laser plasma - PALS; Optical diagnosis; and Teaching, conferences and international cooperation. (P.A.)

123

Evaluation of high temperature accelerated aging tests used on integrated circuits. Final report  

Energy Technology Data Exchange (ETDEWEB)

Accelerated aging tests such as high temperature burn-in, which are in current use on Bendix Kansas City Division's (BKC) purchased small and medium scale integrated circuits, were evaluated to determine if they are effective and necessary to ensure the required reliability. A theoretical analysis, a literature search, and a study of lot acceptance results were used to assess the value of integrated circuit burn-in.

1986-04-01

124

Analysis of high-temperature superconducting films by x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of Cu, Y and Ba in very thin high-temperature superconducting films. The precision of the method is better than 3% for about 1 #mu#m thick films. The atomic emission ICP spectrometry was used to testify results of XRF analysis. An acceptable agreement of both methods was obtained. (author) 4 refs.; 2 tabs.

1991-09-01

125

Promising materials for HTGR high temperature heat exchangers  

International Nuclear Information System (INIS)

The service conditions for high-temperature heat-exchangers with helium coolant of HTGRs and requirements imposed on materials for their production are discussed. The choice of nickel-base alloys with solid-solution hardening for long-term service at high temperatures is grounded. Results of study on properties and structure of types Ni-25Cr-5W-5Mo and Ni-20Cr-20W alloy in the temperature range of 900 deg. - 1,000 deg. C are given. The ageing of Ni-25Cr-5W-5Mo alloy at 900 deg. - 950 deg. C results in decreased corrosion-mechanical properties and is caused by the change of structural metal stability. Alloy with 20% tungsten retains a high stability of both structure and properties after prolonged exposure in helium at above temperatures. The alloy has also increased resistance to delayed fracture and low-cycle fatigue at high temperatures. The developed alloy of type Ni-20Cr-20W ...

1989-06-01

126

Present status and problems of high temperature coatings by thermal spraying system. Yosha ho ni yoru koon coatings by thermal spraying system  

Energy Technology Data Exchange (ETDEWEB)

This report outlines on the corrosive damage which is inherent to a high temperature environment and introduces on thermal spraying system taking an example of a gas turbine. The recent coatings by thermal spraying for high temperature environment are positively used in such applications as a hearth roll for continuous annealing, a roll for hot dipped steelplate, a solid electrolyte for fuel cell, boilers and rockets. The coating formed will be positively used because of a convenient thermal spraying and availability of various sprayable materials. This report describes the following items. Corrosive damage under the high temperature environment. Types of high temperature corrosive coating by a thermal spraying and utilization thereof. Outline of MCrAlX alloy, and merits thereof. Coating to a turbine wing by rduced ...

1990-10-30

127

Evaluation on materials performance of Hastelloy Alloy XR for the High Temperature Engineering Test reactor components. Weldability and high temperature strength properties  

Energy Technology Data Exchange (ETDEWEB)

Weldability and high temperature strength properties of Hastelloy Alloy XR were investigated in order to evaluate the materials performance of base metal and filler metal for the High Temperature Engineering Test Reactor (HTTR) uses. The weldability was examined by means of the chemical analysis in the deposited metals, optical microscopy, FISCO test, hardness measurements and bend test. The high temperature strength properties were investigated through tensile tests at R.T., 800, 900 and 950degC in air, and creep and creep rupture tests at 900 and 950degC in air. The results obtained by each test showed favorable performance. In particular, the bend test which is considered to be critical pass demonstrated low susceptibility to weld cracking through the optimization of B and C contents in the filler metal and by narrowing the groove. Creep rupture strength was ...

1996-07-01

128

Rapamycin (sirolimus) protects against hypoxic damage in primary heart cultures via Na^+/Ca^2^+ exchanger activation  

British Library Electronic Table of Contents (United Kingdom)

Aims: Rapamycin (sirolimus) is an antibiotic that inhibits protein synthesis through mammalian targeting of rapamycin (mTOR) signaling, and is used as an immunosuppressant in the treatment of organ rejection in transplant recipients. Rapamycin confers preconditioning-like protection against ischemic-reperfusion injury in isolated mouse heart cultures. Our aim was to further define the role of rapamycin in intracellular Ca^2^+ homeostasis and to investigate the mechanism by which rapamycin protects cardiomyocytes from hypoxic damage. Main methods: We demonstrate here that rapamycin protects rat heart cultures from hypoxic-reoxygenation (H/R) damage, as revealed by assays of lactate dehydrogenase (LDH) and creatine kinase (CK) leakage to the medium, by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-d...

2011-01-01

129

Effect of Heart Rate on Ventricular Repolarization in Healthy Individuals Applying Vectorcardiographic T Vector and T Vector Loop Analysis  

British Library Electronic Table of Contents (United Kingdom)

Background: Ventricular repolarization (VR) is strongly influenced by heart rate (HR) and autonomic nervous activity, both of which also are important for arrhythmogenesis. Their relative influence on VR is difficult to separate, but might be crucial for understanding while some but not other individuals are at risk for life-threatening arrhythmias at a certain HR. This study was therefore designed to assess the -pure- effect of HR increase by atrial pacing on the ventricular gradient (VG) and other vectorcardiographically (VCG) derived VR parameters during an otherwise unchanged condition. Methods: In 19 patients with structurally normal hearts, a protocol with stepwise increased atrial pacing was performed after successful arrhythmia ablation. Conduction intervals were measured on averag...

2011-01-01

130

Chronic sympathetic activation promotes downregulation of ?-adrenoceptor-mediated effects in the guinea pig heart independently of structural remodeling and systolic dysfunction  

British Library Electronic Table of Contents (United Kingdom)

It is uncertain if downregulation of ?-adrenoceptor signaling pathway is promoted by an enhanced adrenergic tone at an early stage of cardiac disease, or it develops secondary to detrimental local myocardial changes in advanced heart failure. We examined the integrity of ?-adrenoceptor signaling pathway upon chronic infusion of isoproterenol, a ?-adrenoceptor agonist, at a dose producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400??g?kg?1?h?1 over 16?days) to guinea pigs using osmotic minipumps produced no change in cardiac weights, LV internal dimensions, myocyte cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations from isoproterenol-treated guinea ...

2011-01-01

131

A patient specific electro-mechanical model of the heart  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a patient specific deformable heart model that involves the known electrical and mechanical properties of the cardiac cells and tissue. The whole heart model comprises ten Tusscher's ventricular and Nygren's atrial cell models, the anatomical and electrophysiological model descriptions of the atria (introduced by Harrild et al.) and ventricle (given by Winslow et al.), and the mechanical model of the periodical cardiac contraction and resting phenomena proposed by Moireau et al. During the propagation of the depolarization wave, the kinetic, compositional and rotational anisotropy is handled by the tissue, organ and torso model. The applied patient specific parameters were determined by an evolutionary computation method. An intensive parameter reduction was performed u...

2011-01-01

132

Selection and Creep Property of Alloy 617 for the IHX Application  

Energy Technology Data Exchange (ETDEWEB)

Since the very high temperature reactor (VHTR) components such as hot gas ducts and intermediate heat exchanger (IHX) are operated during a design life of 30 to 60 years at 950 .deg. C and 3-8MPa in He impurities, their components are required to have good high temperature strength, creep-rupture strength, high temperature stability, and good corrosion resistance. Among them, creep properties are the most important, because the integrity of their components should be preserved during a design life of over 30 years at the maximum operating temperature up to 1000 .deg. C. So far, there are no materials approved by ASME III which is a nuclear code for temperatures reaching 1000 .deg. C, and until now, a material selection is still left as a key issue. Some leading candidate alloys can be selected from the high temperature ...

2007-07-01

133

HST/ACS observations of shell galaxies: inner shells, shell colours and dust  

CERN Document Server

AIM:Learn more about the origin of shells and dust in early type galaxies. METHOD: V-I colours of shells and underlying galaxies are derived, using HST Advanced Camera for Surveys (ACS) data. A galaxy model is made locally in wedges and subtracted to determine shell profiles and colours. We applied Voronoi binning to our data to get smoothed colour maps of the galaxies. Comparison with N-body simulations from the literature gives more insight to the origin of the shell features. Shell positions and dust characteristics are inferred from model galaxy subtracted images. RESULT: The ACS images reveal shells well within the effective radius in some galaxies (at 1.7 kpc in the case of NGC 5982). In some cases, strong nuclear dust patches prevent detection of inner shells. Most shells have colours which are similar to the underlying galaxy. Some inner shells are redder than the galaxy. All six shell galaxies show out of dynamical equilibrium dust features, like lanes or ...

2007-01-01

134

Evaluation of Dynamic Passing Sight Distance Problem Using a Finite Element Model  

Energy Technology Data Exchange (ETDEWEB)

Sufficient passing sight distance is an important control for two-lane rural highway design to minimize the possibility of a head-on collision between passing and opposing vehicles. Traditionally, passing zones are marked by checking passing sight distance that is potentially restricted by static sight obstructions. Such obstructions include crest curves, overpasses, and lateral objects along highways. This paper proposes a new concept of dynamic sight-distance assessment, which involves restricted passing sight distances due to the impeding vehicles that are traveling in the same direction. Using a finite-element model, the dynamic passing sight-distance problem was evaluated, and the writers analyzed the relationships between the available passing sight distance and other factors such as the horizontal curve radius, impeding vehicle dimensions, and a driver s following distance. It was found that the impeding vehicles may cause substantially insufficient passing ...

2008-06-01

135

ch6-1 - NASA's History Office  

Science.gov (United States)

Composed of Sun sensors, the Canopus sensor, the inertial reference unit, ... The heart of the system was a 100-pound-thrust rocket whose hypergolic, ... The spacecraft's low-gain antenna picked up all incoming signals from the NASA-JPL ...

136

Validity of Cardiac Markers as Diagnostic and Prognostic Indicators of Complications in Patients undergoing Percutaneous Coronary Intervention  

UK PubMed Central (United Kingdom)

ObjectivesThe aim of this study was to assess the diagnostic and prognostic value of heart-type fatty acid-binding protein (H-FABP) in elective percutaneous coronary intervention...Full Text Available

2010-04-01

137

Transmural distribution of extracellular purines in isolated guinea pig heart.  

UK PubMed Central (United Kingdom)

The purine adenosine appears to be involved in regulation of coronary vascular tone. Little is known concerning the levels and distribution of adenosine and related purines in the extracellular fluid...Full Text Available

1991-01-15

138

Transcatheter stent implantation to treat aortic coarctation in infancy.  

UK PubMed Central (United Kingdom)

A ten week old girl who had previously undergone a palliative procedure for the hypoplastic left heart syndrome had unrelieved aortic coarctation that did not respond to standard balloon dilatation....Full Text Available

1993-01-01

139

Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis  

International Nuclear Information System (INIS)

By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these ...

1965-01-01

140

Total prosthetic replacement of atrioventricular valves in the dog  

UK PubMed Central (United Kingdom)

The metal parts of cardiac valve prostheses cause reactions in the surrounding tissues of the heart. In some dogs rather abnormal reactions were found, and were attributed to corrosion of the stainless...Full Text Available

1972-01-01

141

Total Antioxidant Performance Is Associated with Diet and Serum Antioxidants in Participants of the Diet and Physical Activity Substudy of the Jackson Heart Study12  

UK PubMed Central (United Kingdom)

Total antioxidant performance (TAP) measures antioxidant capacities in both hydrophilic and lipophilic compartments of serum and interactions known to exist between them. Our objective was to assess...Full Text Available

2009-10-01

142

Subcellular distribution of ryanodine receptors in the cardiac muscle of carp (Cyprinus carpio).  

Science.gov (United States)

We examined the subcellular localization of ryanodine receptors (RyR) in the cardiac muscle of carp using biochemical, immunohistochemical, and electron microscopic methods and compared it with those of rats and guinea pigs. To achieve this goal, an anti-RyR antibody was newly raised against a synthetic peptide corresponding to an amino acid sequence that was conserved among all sequenced RyRs. Western blot analysis using this antibody detected a single RyR band following the SDS-PAGE of sarcoplasmic reticulum (SR) membranes from carp atrium and ventricle as well as from mammalian hearts and skeletal muscles. The carp heart band had slightly greater mobility than those of mammalian hearts. Although immunohistochemical staining showed evident striations corresponding to the Z lines in longitudinal sections of mammalian hearts, clusters of punctate staining, in contrast, were distributed ubiquitously ...

2003-06-12

143

Some aspects of the pharmacology of an homologous series of choline esters of fatty acids  

UK PubMed Central (United Kingdom)

The pharmacological effects of a series of fatty acid-choline esters have been studied on the isolated rabbit heart, the isolated guinea-pig ileum and the rat stomach. The effect changed with increasing...Full Text Available

1957-03-01

144

Seasonal proteomic changes reveal molecular adaptations to preserve and replenish liver proteins during ground squirrel hibernation  

UK PubMed Central (United Kingdom)

Hibernators are unique among mammals in their ability to survive extended periods of time with core body temperatures near freezing and with dramatically reduced heart, respiratory, and metabolic rates...Full Text Available

2010-02-01

145

Review: Interventional radiology in peripheral vascular disease  

UK PubMed Central (United Kingdom)

Peripheral vascular diseases (PVD) are referred to as diseases affecting the blood vessels other than the heart and the brain. Interventional endovascular treatment whenever feasible has become the...Full Text Available

2008-05-01

146

Resonance Raman enhancement of phenyl ring vibrational modes in phenyl iron complex of myoglobin.  

UK PubMed Central (United Kingdom)

Resonance Raman spectra are reported for the organometallic phenyl-FeIII complexes of horse heart myoglobin. We observed the resonance enhancement of the ring vibrational modes of the bound phenyl group....Full Text Available

1990-04-01

147

Relation of Kidney Function and Albuminuria with Atrial Fibrillation (From the Heart and Soul Study)  

UK PubMed Central (United Kingdom)

Atrial fibrillation (AF) is common in end-stage renal disease (ESRD), but the relationship between more modest decrements in kidney function or albuminuria with AF is uncertain. Among 956 outpatients...Full Text Available

2009-12-01

148

RXR activators molecular signalling: involvement of a PPAR?-dependent pathway in the liver and kidney, evidence for an alternative pathway in the heart  

UK PubMed Central (United Kingdom)

In this study we compared the molecular signalling elicited by rexinoids, selective retinoid X receptor (RXR)-activators, in several organs (i.e. liver, kidney,...Full Text Available

2003-03-01

149

Post traumatic stress symptoms and heart rate variability in Bihar flood survivors following yoga: a randomized controlled study  

UK PubMed Central (United Kingdom)

BackgroundAn earlier study showed that a week of yoga practice was useful in stress management after a natural calamity. Due to heavy rain and a rift on the banks of the Kosi river,...Full Text Available

150

Patent arterial duct  

UK PubMed Central (United Kingdom)

Patent arterial duct (PAD) is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher...Full Text Available

151

Online social support for individuals concerned with heart disease: observing gender differences.  

UK PubMed Central (United Kingdom)

Using a theoretical framework of social support, and content analysis, the content and pattern of support in messages posted in a 4-week period on a commercial health network for individuals concerned...Full Text Available

1999-01-01

152

Myofibrillogenesis in the developing zebrafish heart: A functional study of tnnt2  

UK PubMed Central (United Kingdom)

Various hypotheses have been proposed to explain the molecule processes of sarcomere assembly, partially due to the lack of systematic genetic studies of sarcomeric genes in an in vivo...Full Text Available

2009-07-15

153

MudPIT Analysis: Application to Human Heart Tissue  

UK PubMed Central (United Kingdom)

Although two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) has been used as the standard proteomic approach for separating proteins in a complex mixture, this technique has many drawbacks....Full Text Available

2009-01-01

154

Management of patients with unstable angina/non-ST-elevation myocardial infarction: a critical review of the 2007 ACC/AHA guidelines  

UK PubMed Central (United Kingdom)

Background:In 2007, the American College of Cardiology/American Heart Association (ACC/AHA) published new guidelines for the diagnosis and management of patients with unstable angina/non-ST...Full Text Available

2009-04-01

155

Long-Range Correlations in Rectal Temperature Fluctuations of Healthy Infants during Maturation  

UK PubMed Central (United Kingdom)

BackgroundControl of breathing, heart rate, and body temperature are interdependent in infants, where instabilities in thermoregulation can contribute to apneas or even life-threatening...Full Text Available

156

Lipotoxic heart disease in obese rats: Implications for human obesity  

UK PubMed Central (United Kingdom)

To determine the mechanism of the cardiac dilatation and reduced contractility of obese Zucker Diabetic Fatty rats, myocardial triacylglycerol (TG) was assayed chemically and morphologically. TG was...Full Text Available

2000-02-15

157

Linking Gene Expression and Functional Network Data in Human Heart Failure  

UK PubMed Central (United Kingdom)

BackgroundGene expression profiling and the analysis of protein-protein interaction (PPI) networks may support the identification of disease bio-markers and potential drug targets....Full Text Available

158

Learn CPR You Can Do It!  

Science.gov (United States)

Have a question about CPR? Click Here To Ask The Doctor Learn CPR is a free public service supported by the University of Washington School of Medicine . Learn the basics of CPR - cardiopulmonary resuscitation. The American Heart Association issued updated ...

159

JAMA Patient Page: Cardiopulmonary Resuscitation (CPR)  

Science.gov (United States)

... of the American Medical Association JAMA PATIENT PAGE Cardiopulmonary Resuscitation W hen the heart stops beating (cardiac arrest), ... circulation (blood flow) returns or is restored. Providing cardiopulmonary resuscitation ( CPR ) is a way to keep some circulation ...

160

Isolation of a bacterium resembling Pirellula species from primary tissue culture of the giant tiger prawn (Penaeus monodon).  

UK PubMed Central (United Kingdom)

During attempts to establish tissue cultures from hepatopancreas, heart, and hemolymph of the giant tiger prawn (Penaeus monodon), using a medium including penicillin, streptomycin, and amphotericin...Full Text Available

1991-11-01

161

Impact of sphingomyelin levels on coronary heart disease and left ventricular systolic function in humans  

UK PubMed Central (United Kingdom)

Sphingomyelin (SM) is an abundant phospholipid in cell membranes and in lipoproteins. In human plasma, SM is mainly found in atherogenic lipoproteins; therefore, higher levels of SM may promote atherogenesis....Full Text Available

162

If I Had - A Family History of Heart Disease  

Medline Plus

... Hospital & University Hospital Basel) If I Had - Pre-diabetes - Dr. Venkat Narayan, MD, MSc, MBA, Rollins School ... School, Massachusetts General Hospital, Discusses the Treatment of Diabetes Back to Home Page If I Had - A ...

163

Heterotopic transcatheter tricuspid valve implantation: first-in-man application of a novel approach to tricuspid regurgitation  

UK PubMed Central (United Kingdom)

AimsTranscatheter treatment of heart valve disease is well established today. However, for the treatment of tricuspid regurgitation (TR), no effective catheter-based approach is...Full Text Available

2011-05-01

164

Heart Rate Characteristics: Physiomarkers for Detection of Late-Onset Neonatal Sepsis  

UK PubMed Central (United Kingdom)

SynopsisEarly detection of late onset neonatal sepsis, prior to obvious and potentially catastrophic clinical signs, is an important goal in neonatal medicine. Sepsis causes a...Full Text Available

2010-09-01

165

From antibody insult to fibrosis in neonatal lupus - the heart of the matter  

UK PubMed Central (United Kingdom)

Few diseases exemplify the integration of research from bench to bedside as well as neonatal lupus, often referred to as a model of passively acquired autoimmunity. In essence, this disease encompasses...Full Text Available

2003-01-01

166

Evaluation of a diagnostic algorithm for heart disease in neonates.  

UK PubMed Central (United Kingdom)

OBJECTIVE--To develop, test, and validate an algorithm for diagnosing disease in neonates during an over the telephone referral to a specialist cardiac centre. DESIGN--A draft algorithm requiring only...Full Text Available

1991-04-20

167

Effects of p-Synephrine alone and in Combination with Selected Bioflavonoids on Resting Metabolism, Blood Pressure, Heart Rate and Self-Reported Mood Changes  

UK PubMed Central (United Kingdom)

Bitter orange (Citrus aurantium) extract is widely used in dietary supplements for weight management and sports performance. Its primary protoalkaloid is p-synephrine....Full Text Available

168

Effects of gradual coronary artery occlusion and exercise training on gene expression in swine heart  

UK PubMed Central (United Kingdom)

Gradual occlusion (O) of the swine left circumflex coronary artery (LCX) with an ameroid occluder results in complete O within 3 weeks, collateral vessel development, and compensatory hypertrophy....Full Text Available

2007-01-01

169

Clinical Application of Ischemic Preconditioning in the Elderly  

UK PubMed Central (United Kingdom)

A mild stress such as brief ischemic episodes may protect the heart from a successive and more prolonged myocardial ischemia (ischemic preconditioning). This phenomenon is considered a typical “hormetic...Full Text Available

170

Body mass index, waist circumference, and risk of coronary heart disease: a prospective study among men and women  

UK PubMed Central (United Kingdom)

ObjectiveThe purpose of the study was to assess the risk of CHD associated with excess weight measured by BMI and waist circumference (WC) in two large cohorts of...Full Text Available

2010-01-01

171

Association of B-Type Natriuretic Peptide Levels With Estimated Glomerular Filtration Rate and Congestive Heart Failure  

UK PubMed Central (United Kingdom)

Background: The causes of elevated B-Type natriuretic peptide (BNP) levels are multifactorial. Renal dysfunction has been shown to affect BNP levels in some studies and...Full Text Available

2010-03-01

172

Anxiety in Patients with Cardiac Disease.  

Science.gov (United States)

Anxiety may cause adverse outcomes through physiologic pathways in patients with cardiac disease. The purpose of this dissertation was to investigate anxiety and its correlates in persons with acute myocardial infarction (AMI) and heart failure (HF). The ...

2005-01-01

173

Angina with a normal coronary angiogram caused by amyloidosis  

UK PubMed Central (United Kingdom)

A case of severe intractable angina pectoris with normal angiography is presented. Following video assisted thoracic sympathectomy the patient died of heart failure. Microvascular cardiac amyloidosis...Full Text Available

2004-09-01

174

An Integrated System for Total Cardiac Monitoring of the Critically Ill  

UK PubMed Central (United Kingdom)

An integrated system of micro-and mini-computers is described to acquire, analyze, store and report data on the total activity of the heart of a critically ill patient. Real-time beat and rhythm diagnoses...Full Text Available

1977-10-05

175

Acute atrial arrhythmogenicity and altered Ca2+ homeostasis in murine RyR2-P2328S hearts  

UK PubMed Central (United Kingdom)

AimsThe experiments explored for atrial arrhythmogenesis and its possible physiological background in recently developed hetero-(RyR2+/S) and homozygotic...Full Text Available

2011-03-01

176

'Hair-on-end' skull changes resembling thalassemia caused by marrow expansion in uncorrected complex cyanotic heart disease  

Energy Technology Data Exchange (ETDEWEB)

''Hair-on-end'' skull changes resembling thalassemia were rarely described in the 1950s and 1960s in children with cyanotic congenital heart diseases; these changes were described almost entirely in patients with tetralogy of Fallot or D-transposition of the great arteries. As these lesions have become correctable, the osseous changes, never common, seem now only to exist in a small number of patients with uncorrectable complex cyanotic congenital heart disease who survive in a chronic hypoxic state. We present two cases: a case of marked marrow expansion in the skull of a 5-year-old boy with uncorrectable cyanotic heart disease studied by CT, and a second case of an 8-year-old with tetralogy of Fallot and pulmonary atresia studied by plain skull radiographs. The true incidence of these findings is unknown. (orig.)

2005-07-01

177

Quantitative non-destructive evaluation of high-temperature superconducting materials  

Energy Technology Data Exchange (ETDEWEB)

Even though the currently intensive research efforts on high- temperature superconducting materials have not yet converged on a well specified practical material, the indications are that such a material may be quite brittle, anisotropic, and may contain many flaws such as microcracks and voids at grain boundaries. Consequently, practical applications of high temperature superconducting materials will require a very careful strength analysis based on fracture mechanics considerations. Because of the high sensitivity of the strength of such materials to the presence of defects, methods of quantitative non-destructive evaluation may be expected to play an important role in strength determinations. This proposal is concerned with the use of ultrasonic methods to detect and characterize isolated cracks, clusters of microcracks and microcracks distributed throughout the material. Particular attention has ...

1991-06-14

178

Observation of Fluorescence for some lanthanides in LiCl-KCl molten salt media at high temperature  

Energy Technology Data Exchange (ETDEWEB)

To our knowledge, the fluorescence studies of lanthanides in LiCl-KCl eutectic molten salt at a high temperature are not reported yet. The fluorescence of the lanthanide-ions was generally decreased when the temperature was increased. Moreover, the fluorescence of the lanthanides was strong when the sample was solidified to or from the melt. The temperature, where the fluorescence was decreased, was identified to be different depending on the species of the lanthanides and the substrates was considered to possibly be from quenching of the fluorescence due to either the collisions of melted samples induced by high temperature media or the re-absorption of fluorescence by the samples. Several comparison experiments were performed to explain and understand this phenomenon and improve the fluorescence. In this way, an on-line monitoring of chemical species and the concentration for lanthanides elements in ...

2008-08-15

179

High-temperature investigations of the rare earth NZP phosphates R {sub 1/3}Zr{sub 2}(PO{sub 4}){sub 3} (R = La, Nd, Eu, Lu) by drop calorimetry  

Energy Technology Data Exchange (ETDEWEB)

The high-temperature enthalpy increments of the phosphates La{sub 1/3}Zr{sub 2}(PO{sub 4}){sub 3}, Nd{sub 1/3}Zr{sub 2}(PO{sub 4}){sub 3}, Eu{sub 1/3}Zr{sub 2}(PO{sub 4}){sub 3} and Lu{sub 1/3}Zr{sub 2}(PO{sub 4}){sub 3} have been measured by high-temperature drop calorimetry in the temperature range 484.5-1090.7 K. From these results the heat capacity of the studied compounds has been derived.

2007-07-31

180

GaP/Al/sub x/Ga/sub 1-x/P heterojunction transistors for high-temperature electronic applications  

Science.gov (United States)

Useful bipolar transistor action over the temperature range from -195 to 550 /sup 0/C has been demonstrated for heterojunction bipolar transistors in the GaP/AlGaP chemical system. This represents the highest temperature at which useful bipolar solid-state transistor action has ever been demonstrated in any material. Improvements in the materials technology and in the understanding of device characteristics at high temperatures were essential to the successful fabrication of these devices. These results demonstrate that the GaP/AlGaP heterojunction system is an excellent technology for active electronic components operated at high temperatures.

1983-10-01

181

Electrochemical properties and growth mechanism of passive films on Alloy 690 in high-temperature alkaline environments  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on Alloy 690 in high-temperature alkaline environments were investigated by potentiodynamic polarization, X-ray photoelectron spectroscopy, transmission electron microscopy and Mott-Schottky approach. Passive current density and donor density of the passive films increase with increasing temperature, due to increased diffusion rates of metallic ions and dehydration of hydroxide phases. The passive films show a duplex structure including an inner layer of fine-grained Cr oxide or spinel oxide and an outer layer of Ni-Fe spinel oxide and Ni hydroxide. A growth model of the passive films on Alloy 690 in high-temperature alkaline environments is proposed and discussed.

2010-10-15

182

Electrochemical properties and growth mechanism of passive films on Alloy 690 in high-temperature alkaline environments  

International Nuclear Information System (INIS)

Passive films formed on Alloy 690 in high-temperature alkaline environments were investigated by potentiodynamic polarization, X-ray photoelectron spectroscopy, transmission electron microscopy and Mott-Schottky approach. Passive current density and donor density of the passive films increase with increasing temperature, due to increased diffusion rates of metallic ions and dehydration of hydroxide phases. The passive films show a duplex structure including an inner layer of fine-grained Cr oxide or spinel oxide and an outer layer of Ni-Fe spinel oxide and Ni hydroxide. A growth model of the passive films on Alloy 690 in high-temperature alkaline environments is proposed and discussed.

2010-10-01

183

Effects of boron addition on weldability and high temperature strength properties of Hastelloy alloy XR  

Energy Technology Data Exchange (ETDEWEB)

The effects of boron addition on weldability and high temperature strength properties were investigated for Hastelloy alloy XR used TIG welding process with the filler metals. Four versions of filler metals with different boron contents were used. The results obtained may be summarized as follows: (1) The influence of boron addition on weldability was not observed within the range of the present experiment. (2) The result of chemical analysis for deposited metals showed that boron desorption did not occur during welding. (3) The tensile properties of weldments, particularly in high temperature ductility were raised with increasing boron content. (4) In the creep properties of weldments, creep rupture life increased with increasing boron content under the given stress conditions. (author).

1990-11-01

184

Effects of boron addition on weldability and high temperature strength properties of Hastelloy alloy XR  

International Nuclear Information System (INIS)

The effects of boron addition on weldability and high temperature strength properties were investigated for Hastelloy alloy XR used TIG welding process with the filler metals. Four versions of filler metals with different boron contents were used. The results obtained may be summarized as follows: 1) The influence of boron addition on weldability was not observed within the range of the present experiment. 2) The result of chemical analysis for deposited metals showed that boron desorption did not occur during welding. 3) The tensile properties of weldments, particularly in high temperature ductility were raised with increasing boron content. 4) In the creep properties of weldments, creep rupture life increased with increasing boron content under the given stress conditions. (author).

185

Development and validation of a CATHENA fuel channel model for a post-blowdown analysis of the high temperature thermal-chemical experiment CS28-1  

British Library Electronic Table of Contents (United Kingdom)

To form a licensing basis for a new methodology for a fuel channel safety analysis code for CANDU-6 nuclear reactor, a CATHENA model for a post-blowdown fuel channel analysis has been developed, and tested for a high temperature thermal-chemical experiment CS28-1 [Lei, Q.M., 1993. Post-test analysis of the 28-element high-temperature thermal-chemical experiment CS28-1. In: 4th International Conference on Simulation Methods in Nuclear Engineering, Montreal, PQ, 1993]. Pursuant to the objective of this investigation, the current study has focused on understanding the involved phenomena, their interrelations, and how to maintain a good accuracy of the temperature and H2 generation rate prediction without losing the important physics of the involved phenomena. The transient simulation results ...

2009-01-01

186

Carbon dioxide absorption mechanisms of sodium added to calcium oxide at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

To apply the CO{sub 2} absorber at about 1000{sup o}C for integrated coal gasification combined cycle (IGCC) furnace, the reactions of calcium oxide and CO{sub 2} at high temperatures was examined. Calcium carbonate reacts with sodium hydrogen carbonate below 200{sup o}C and forms sodium-calcium complex carbonate. The sodium-calcium complex carbonate melts at 813{sup o}C, and the carbon dioxide absorption and discharge reversible reactions of calcium-oxide takes place via liquid at around 1000{sup o}C. Sintering of calcium oxide at high temperature has been successfully avoided by the addition of sodium.

2004-07-01

187

Rapid clearance of iodine-131 MIBG from the heart and liver of patients with adrenergic dysfunction and pheochromocytoma  

Energy Technology Data Exchange (ETDEWEB)

Iodine-131 MIBG, a radiolabeled adrenergic neuron-blocking agent, decreased rapidly from the heart and liver of patients with adrenergic dysfunction and pheochromocytoma when compared with eight controls. However, there was no significant difference in the rate of (/sup 131/I)MIBG decrease in these organs between controls and patients in the intervals subsequent to 4 hr. These findings suggest that adrenergic neuronal uptake of (/sup 131/I)MIBG in these organs is smaller in the patients than in the controls. Measurements of time-activity relationships of radioiodinated MIBG may be useful for assessment of adrenergic function of these organs and thus of generalized disorders of adrenergic innervation.

1985-04-01

188

Single Molecule Source Reagents for CVD of Beta Silicon Carbide.  

Science.gov (United States)

Beta silicon carbide is an excellent candidate semiconductor material for demanding applications in high power and high temperature electronic devices due to its high breakdown voltage, relatively large band gap, high thermal conductivity and high melting...

1991-01-01

189

Research and development program on solar thermal use in the high temperature range. Forschungs- und Entwicklungsprogramm zur solarthermischen Nutzung im Hochtemperaturbereich  

Energy Technology Data Exchange (ETDEWEB)

In the context of the research project, the physical basis of the direct decoupling of highly concentrated solar radiation in materials without the detour via absorbing heat exchanger walls was examined. Also, the first chemical processes suitable for the effective long-term storage of solar energy were analysed, relevant experiments were carried out and the necessary receiver techniques for high temperature applications were provided. The principle of direct coupling was examined on fluidized beds on the one hand and on cavity receivers, on the other hand. The contribution shows the results achieved in detail. It is recorded that first processes for storing solar energy in chemical reactions were able to be examined. Alkaline earth hydroxides accommodated in ceramic honeycomb structures seem to be possible as stores for medium temperature ranges around 500deg C. Investigations on receiver structure materials are also making progress. Highly ...

1988-03-01

190

Research and development for the upgrading of Rhenish brown coal  

Energy Technology Data Exchange (ETDEWEB)

Product control procedures, the development of new technologies, and the extension of the applications of solid fuels are described. Hydrogasification and high-temperature Winkler gasification are discussed. The design and function of a continuous, semi-industrial plant for hydrogenating liquefaction in the sump phase are gone into. (MOS).

1988-07-01

191

Quality assurance requirements for installation, inspection, and testing of mechanical equipment and systems  

International Nuclear Information System (INIS)

The guide describes a method acceptable to the NRC staff for complying with the Commission's regulations with regard to quality assurance requirements for installation, inspection, and testing of mechanical equipment and systems for water-cooled and high-temperature gas-cooled nuclear power plants.

192

Influence of Yttrium Addition and Superficial Y(sub 2)O(sub 3) ...  

Science.gov (United States)

... Title : Influence of Yttrium Addition and Superficial Y(sub 2)O(sub 3) Powder Application to Fe-26Cr-21Ni-1.8Si Alloy on Its High Temperature ...

1984-02-01

193

Experiments With Phase at Very High Pressure - NASA Technical ...  

Science.gov (United States)

The A-15 compounds Nb3Sn, V3Si, etc., have been studied extensively as high temperature superconductors. High pressure studies were carried ...

194

Effect of the molybdenum content and of further factors on the creep strength of high-temperature, CrMoV alloy tube steels. [chemical composition of the steels 0,4-1,2% Cr, 0,2-1% Mo, 0,15-0,3% V  

Energy Technology Data Exchange (ETDEWEB)

With regard to long-term high-temperature strength, molybdenum is an effective alloying element but rather expensive as well. The author describes its influence on high-temperature strength properties of CrMoV alloyed steel. Besides molybdenum, also vanadium and carbon have an increasing effect on limiting rupture stress which furthermore may be effected by heat treatment, the cooling rate being a dominating factor in this process. To guarantee optimum long-term high-temperature strength properties, a minimum of a least 0.5% Mo and 0.35% V is required. The cooling rate after austentizing must be high enough to enable transformation in the bainitic structure to take place. A two-to-three-hour tempering treatment at about 720/sup 0/C is regarded as an optimum.

1988-07-01

195

Effect of V and W addition on the high temperature strength properties of 12%Cr-15%Mn austenitic steels. 12%Cr-15%Mn austenite ko no ondo kyodo ni oyobosu V to W tenka no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Experimental discussions were given on effect of V and W addition on the high temperature strength properties of 12% Cr-15% Mn austenite steels. The test samples were added with W at 0% to 3.5% and V at 0% to 0.5% in addition to C and N, and were given aging treatment or solution treatment. This paper describes the following matters on the results of high-temperature strength measurements and structural observation: A remarkable trend was observed that M23 Cb type carbides precipitate in the aging treatment, wherein aging hardening appears prominently which is attributable to ultra-fine deposits of vanadium nitride (VN) in the V-added material; the V addition is very effective in increasing the high-temperature tensile strength and creep fracture strength as compared with single W addition, wherein the said carbides that accelerate the precipitation as a result of the V addition make a large ...

1992-11-01

196

CaF sub 2 passivation layers for high temperature superconductors  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method comprising applying a passivation layer of CaF{sub 2} to the surface of a superconductive ceramic oxide by evaporation. The CaF{sub 2} layer is effective to passivate the oxide surface without disrupting the superconductive properties.

1990-10-23

197

Atomic-scale insight and design principles for turbine engine thermal barrier coatings from theory  

UK PubMed Central (United Kingdom)

To maximize energy efficiency, gas turbine engines used in airplanes and for power generation operate at very high temperatures, even above the melting point of the metal alloys from which they are...Full Text Available

2011-04-05

198

Alternate alloying for environmental resistance; Proceedings of the Symposium, New Orleans, LA, Mar. 2-6, 1986  

Energy Technology Data Exchange (ETDEWEB)

Papers are presented on the development of oxidation- and sulfidation-resistant ferritic alloys; the microstructural stability of sulfidation-resistant FeCrAl stainless steels around 500 C; age hardening in Fe-Mn-Al-C austenitic alloys; the oxidation/corrosion behavior of low-Cr Fe-Cr-Ni alloys containing Zr or Nb; the high temperature oxidation/corrosion of iron-based superalloys; and the role of Mo in the Na/sub 2/SO/sub 4/ induced corrosion of superalloys at high temperature. Topics discussed include the effect of variations of Co content on the cyclic oxidation resistance of selected Ni-base superalloys; high temperature oxidation of Fe based alloys; the morphological development of high temperature oxide scales of Fe-Mn-Al base alloys; and the oxidation of an Fe-Mn-Al-C alloy at 1000 C. Consideration is given to the ...

1987-01-01

199

A thermochemical hydrogen production system based on a high-temperature fusion reactor blanket  

International Nuclear Information System (INIS)

A conceptual fusion synfuel production system has been developed with the unique features of: (1) a fusion blanket producing high-temperature (1250"0C) process heat, and (2) the GA sulfur-iodine thermochemical cycle. The system incorporates a two-zone blanket which achieves a tritium breeding ratio of 1.1 while delivering a high fraction (30%) of the fusion heat at high temperatures (1250"0C). The multiple barriers to tritium permeation in the blanket design permit the hydrogen product to meet 10CFR20 regulatory requirements without stringent requirements on the tritium recovery systems. A ceramic heat exchanger, incorporating SiC tubes and headers to contain the process stream and a cooled, Inconel 718 pressure shell to contain the helium, was designed for transferring the heat from the high-temperature coolant to the process. A good heat-line match of the blanket heatsource temperature distribution to ...

1983-04-26

200

The study of thermal characteristics of high temperature oven for atomic spectroscopy  

International Nuclear Information System (INIS)

We present a high temperature heat oven with merits of conventional heat pipe oven and study ots thermal characteristics. The oven consists of stainless steel body and heating part of three layers of ceramic tubes. We obtained the maximum temperature of about 1350. deg. C at the center which was measured by thermocouple and infrared thermometer. And we compared the heating characteristics in the cases of external heating and no extent heating. It was applied to self diffraction experiment in the samarium gas which was one of the high melting point material.

1997-11-01

201

Strain softening and hardening effects in Ti-6Al-4V during high temperature deformation  

International Nuclear Information System (INIS)

Effect of strain and temperature on high temperature deformation properties of an alpha + beta titanium alloy Ti-6Al-4V has been investigated in the temperature range 800 to 910 deg. C by using the method of cross head speed cycling. On the basis of flow stress strain rate-strain rate sensitivity data and microstructural studies of the undeformed and deformed regions of tensile test pieces, both strain introduced hardening and softening effects were observed during the course of deformation which could be associated with grain coarsening and refining respectively. (author)

202

Steady-state neutronic investigations to the accident of water ingress in systems with pebble-bed high-temperature gas-cooled reactor fuel  

Energy Technology Data Exchange (ETDEWEB)

For light water reactors, loss of coolant is an important point in safety analysis, whereas for gas-cooled reactors the ingress of water into the core region is an incident of safety relevance. The applicability of the computer code system GAMTEREX to pebble beds of spherical high-temperature gas-cooled reactor fuel elements with simulated water ingress is verified by experiment. The measurements were performed at a Siemens-Argonaut reactor, using its ring core as a driver zone for a pebble-bed core in the center of the reactor.

1987-09-01

203

Simple method for the high-temperature isolation of /sup 111/In from silver  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative high-temperature isolation of /sup 111/In from silver irradiated by ..cap alpha..-particles into a gas phase containing a mixture of HCl and H/sub 2/O with a total pressure of about 3 Pa for these gases. It is shown that the indium evolved into the gas phase probably occurs in the form of at least three compounds, viz.., the trichloride, monochloride, and oxychloride, which have adsorption temperatures on quartz of around 385, 475, and 655 K, respectively. All these compounds are readily washed from the surface of quartz apparatus by a weak (0.05 M) solution of hydrochloric acid.

1987-07-01

204

Secondary hazards of high power laser beam welding  

International Nuclear Information System (INIS)

Hazardous UV-radiation and short-wavelength visible (blue) light is emitted by the high temperature plasma above the welding-keyhole. Ozone and NO_x is produced due to UV-induced photodissociation of oxygen and high temperature gas-phase reactions. Spectral measurements of the plasma emission show that the allowed dose for UV-radiation and blue light exposure per work day can be exceeded in as short as a few seconds. Similarly, measurements and models of the ozone and NO_x concentration show that the maximum workplace concentrations might be reached quickly if no appropriate exhaust and filter system is installed. (author)

1996-01-01

205

Operation of a high temperature ion source at the helium-jet on-line isotope separator facility HELIOS  

Energy Technology Data Exchange (ETDEWEB)

The performance of a high temperature ion source coupled to a helium gas-jet transport system for an efficient mass separation of neutron-rich alkaline earth and lanthanide isotopes is reported and the results of overall efficiency measurements using different cluster materials in the gas-jet are given. A fast, microprocessor controlled tape transport system for ..gamma..-spectroscopic studies on short-lived isotopes is described. Some results on the decay of 3.8sub(-s) /sup 152/Pr are presented. (orig.).

1985-02-01

206

Operation of a high temperature ion source at the helium-jet on-line isotope separator facility HELIOS  

Energy Technology Data Exchange (ETDEWEB)

The performance of a high temperature ion source coupled to a helium gas-jet transport system for an efficient mass separation of neutron-rich alkaline earth and lanthanide isotopes is reported and the results of overall efficiency measurements using different cluster materials in the gas-jet are given. A fast, microprocessor controlled tape transport system for ..gamma..-spectroscopic studies on short-lived isotopes is described. Some results on the decay of 3.8sub(-s) /sup 152/Pr are presented.

1985-02-01

207

Ionizing radiation hardening procedure of CCD's  

International Nuclear Information System (INIS)

The procedure of charge-coupled devices (CCD) are investigated by using MOS capacitors for enhancing their ionizing radiation tolerance. Authors have found that the gate oxidation temperature, thickness of SiO_2 gate insulator and high temperature processes after gate oxidation are crucial for determining the radiation tolerance of the devices, and proposed to decrease the thickness of gate insulator, perform gate oxidation at 1000 deg C by means of dry oxidation and minimize the number of high temperature procedure steps after gate oxidation. All stated above is a necessary preparation for priducing radiation hardened charge-coupled devices.

208

Ion beam analysis of high temperature superconducting samples  

Energy Technology Data Exchange (ETDEWEB)

Characterization of high temperature superconducting film and bulk samples has been carried out using 2 MeV [alpha]-particle Rutherford backscattering, 2.4 MeV proton elastic scattering, 2.4 MeV proton-induced x-ray emission, 9 MeV proton induced [gamma]-ray emission and 100 MeV iodine elastic recoil detection analysis techniques. The objective was to compare different ion beam based techniques for: (i) compositional analysis; and (ii) consistency of the results obtained for samples prepared using similar preparation methodology. (author).

1994-02-01

209

High-temperature reactor's attractiveness lies in passive safety. Fierce competition between nuclear and solar energy expected for the year 205  

Energy Technology Data Exchange (ETDEWEB)

In the recent years the use of nuclear energy has turned from a technical and scientific issue to a political one. The high-temperature reactor (HTR) however, has always been advertised as particularly safe. The present situation and future developments of HTR-technology were the two issues that VDI-News brought up on the 27th October on an HTR-conference in an interview with the 'spiritual father' of the HTR, Prof. Dr. Rudolf Schulten of the Juelich Nuclear Research Centre.

1987-11-13

210

High temperature fatigue example of creep life time prediction for grade 2 alloy 800 at 550 C  

Energy Technology Data Exchange (ETDEWEB)

Experimental data on the material characteristics of structures subjected to thermal and mechanical cycling are needed for designing structural parts for creep and creep-fatigue interaction. Moreover, high-temperature low-cycle fatigue data are not sufficient to predict the fatigue creep lifetime. In order to check the reliability of steam generators, tests on pipe materials are conducted under cyclic thermal loading. The tests have been performed on an iron-nickel chromium alloy (alloy 800). Isothermal low-cycle fatigue tests have been conducted at 550 C. 15 refs.

1994-04-01

211

HTR looking forward to his future with confidence. An interview with Professor R. Schulten, the father of the high-temperature reactor  

Energy Technology Data Exchange (ETDEWEB)

The days of high-temperature reactors in the Federal Republic of Germany are numbered. The AVR has been decommissioned, and an application has been filed for licensing the decommissioning of the THTR. Nevertheless, Prof. Dr. Rudolf Schulten who is the director of Juelich Nuclear Research Center's Institute for Reactor Development, and also full professor of Aachen Technical University in the field of reactor safety, predicts a good future for the HTR reactor line on a worldwide level, due to the inherent safety of this reactor type. (orig.).

1989-06-02

212

Electron self-energy of high temperature superconductors as revealed by angle-resolved photoemission.  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we review some of the work our group has done in the past few years to obtain the electron self-energy of high temperature superconductors by analysis of angle-resolved photoemission data. We focus on three examples which have revealed: (1) a d-wave superconducting gap, (2) a collective mode in the superconducting state, and (3) pairing correlations in the pseudogap phase. In each case, although a novel result is obtained which captures the essence of the data, the conventional physics used leads to an incomplete picture. This indicates that new physics needs to be developed to obtain a proper understanding of these materials.

1997-12-05

213

Development of commercial high temperature gas-cooled reactor in China  

Energy Technology Data Exchange (ETDEWEB)

The high temperature gas-cooled test reactor HTR-10 achieved the first criticality in last December in Institute of Nuclear Energy Technology of Tsinghua University in Beijing. Fuji Electric and Nissho Iwai have a cooperative information exchange agreement on the commercialization of the HTGRs with INET, and held an information exchange meeting in last March in INET. INET has started a study on the modification of the HTR-10 to couple with gas turbine system and a pre-feasibility study on the commercial HTGR under the cooperation with China State Power Company. The experiences and abilities of INET in the field of the HTGR and the aggressive plan for commercialization of the HTGR in China are summarized and discussed. (author)

2001-07-01

214

Vladimir P. Demikhov, a pioneer of organ transplantation.  

Science.gov (United States)

Vladimir P. Demikhov was born in a Russian peasant family in 1916. As a biology student at The Moscow University in 1937, he constructed a metal artificial heart and maintained the circulation of a dog for 5.5 hours. From 1946, after his military service, he worked in the Surgical Institute of The Moscow Academy of Sciences performing heterotopic heart transplantations in dogs. In 1947, he performed the first orthotopic lung transplant. Later he performed complex cardiothoracic transplantations as well as renal and hepatic transplantations. He restarted his investigations with the artificial heart and performed coronary bypass operations in dogs. In 1954 he performed a head transplantation, for which he gained worldwide infamy. Stalinist propaganda advertised this fact as the superiority of Soviet science. In fact, it was the upper body of a smaller dog to the neck of a bigger one. The two heads could eat and drink ...

2011-05-01

215

Novel snake venom ligand dendroaspis natriuretic peptide is selective for natriuretic peptide receptor-A in human heart: downregulation of natriuretic peptide receptor-A in heart failure.  

Science.gov (United States)

The natriuretic peptides are considered to be cardioprotective; however, their receptors have not been identified in human myocardium using radiolabeled analogs. Dendroaspis natriuretic peptide (DNP) has been recently identified as a new member of this peptide family and is thought to be less susceptible to enzymatic degradation. Therefore, we have developed the novel radiolabeled analog [125I]-DNP and used this to localize high-affinity (K(D)=0.2 nmol/L), saturable, specific binding sites in adult human heart (n=6) and coronary artery (n=8). In competition binding experiments, atrial natriuretic peptide and brain type natriuretic peptide had greater affinity for [125I]-DNP binding sites than C-type natriuretic peptide and the natriuretic peptide receptor (NPR)-C ligand, cANF. This rank order of potency suggested binding of [125I]-DNP was specific to NPR-A. Messenger RNA encoding NPR-A was identified in left ventricle and coronary artery smooth muscle, and ...

2006-06-15

216

Effects of ischemic-like insult on myocardial /sup 201/Tl accumulation  

Energy Technology Data Exchange (ETDEWEB)

Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The fraction of /sup 201/Tl content in injured compared with control hearts was not significantly lower after 1 hour of insult. By ...

1983-04-01

217

Effects of chronic swimming training on cardiac sarcolemmal function and composition.  

Science.gov (United States)

Cardiac contractile function is dependent on the integrity and function of the sarcolemmal membrane. Swimming exercise training is known to increase cardiac contractile performance. The purpose of the present study was to examine whether a swimming exercise program would alter sarcolemmal enzyme activity, ion flux, and composition in rat hearts. After approximately 11 wk of exercise training, cardiac myosin and actomyosin Ca2+-adenosinetriphosphatase (ATPase) activity was significantly higher in exercised rat hearts than in sedentary control rat hearts. Glycogen content was increased in plantaris and gastrocnemius muscles from exercised animals as was succinic dehydrogenase activity in gastrocnemius muscle of exercised rats in comparison to sedentary rat preparations. Sarcolemmal vesicles were isolated from hearts of exercise-trained and control rats. Sarcolemmal Na+-K+-ATPase and ...

1989-04-01

218

Alterations in heart looping induced by overexpression of the tight junction protein Claudin-1 are dependent on its C-terminal cytoplasmic tail.  

Science.gov (United States)

In vertebrates, the positioning of the internal organs relative to the midline is asymmetric and evolutionarily conserved. A number of molecules have been shown to play critical roles in left-right patterning. Using representational difference analysis to identify genes that are differentially expressed on the left and right sides of the chick embryo, we cloned chick Claudin-1, an integral component of epithelial tight junctions. Here, we demonstrate that retroviral overexpression of Claudin-1, but not Claudin-3, on the right side of the chick embryo between HH stages 4 and 7 randomizes the direction of heart looping. This effect was not observed when Claudin-1 was overexpressed on the left side of the embryo. A small, but reproducible, induction of Nodal expression in the perinodal region on the right side of the embryo was noted in embryos that were injected with Claudin-1 retroviral particles on their right sides. However, no changes in Lefty,Pitx2 or cSnR ...

2006-02-24

219

Theory and delivery of health programming in the community: the Pawtucket Heart Health Program.  

Science.gov (United States)

The Pawtucket Heart Health Program is one of the community studies examining whether population-based efforts to lower cardiovascular risk factors will reduce cardiovascular morbidity and mortality. The Pawtucket Heart Health Program intervention is based on a blend of social learning theory, community organization models, community psychology tenets, and diffusion research. This model allows for multifaceted programs that target individuals, groups, organizations, and the entire community to alter their cardiovascular risk through managing blood pressure, lowering blood cholesterol, quitting smoking, increasing fitness, and maintaining desirable weight levels. A dominant feature of the intervention is the emphasis that it places on volunteers for program delivery. The role of volunteers in providing direct services to help citizens lower their blood pressure and lose weight is highlighted to demonstrate the feasibility and effectiveness of ...

1987-01-01

220

Prevention and Treatment of Functional and Structural Radiation Injury in the Rat Heart by Pentoxifylline and Alpha-Tocopherol  

British Library Electronic Table of Contents (United Kingdom)

Purpose Radiation-induced heart disease (RIHD) is a severe side effect of thoracic radiotherapy. This study examined the effects of pentoxifylline (PTX) and a-tocopherol on cardiac injury in a rat model of RIHD. Methods and Materials Male Sprague-Dawley rats received fractionated local heart irradiation with a daily dose of 9 Gy for 5 days and were observed for 6 months after irradiation. Rats were treated with a combination of PTX, 100 mg/kg/day, and a-tocopherol (20 IU/kg/day) and received these compounds either from 1 week before until 6 months after irradiation or starting 3 months after irradiation, a time point at which histopathologic changes become apparent in our model of RIHD. Results Radiation-induced increases in left ventricular diastolic pressure (in mm Hg: 35 +- 6 after sham...

2008-01-01

221

Anti-muscarinic actions of mitoxantrone in isolated heart muscles of guinea pigs.  

Science.gov (United States)

A hypotheses that mitoxantrone is a competitive antagonist at muscarinic cholinergic receptors was examined in guinea-pig hearts. In isolated left atrial muscle preparations, electrically paced at 2 Hz, the muscarinic agonist, carbachol, caused a concentration-dependent decrease in developed tension. Mitoxantrone caused a parallel right-ward shift of the concentration-response curve for carbachol. Schild plots for the effect of mitoxantrone on the carbachol concentration-response relationship were linear with a slope of 0.88 which was not significantly different from the unity. The right-ward shift of the carbachol concentration-response relationship by mitoxantrone significantly reversed after an additional incubation with a mitoxantrone-free solution, although the reversal was incomplete after a 2-h incubation in the mitoxantrone-free solution. Mitoxantrone caused a concentration-dependent displacement of specific [3H]quinuclidinyl benzilate binding to membrane ...

2000-10-27

222

Ambient air pollution and congenital heart disease: a register-based study.  

Science.gov (United States)

Maternal exposure to ambient air pollution has increasingly been linked to adverse pregnancy outcomes. The evidence linking this exposure to congenital anomalies is still limited and controversial. This case-control study investigated the association between maternal exposure to ambient particulate matter with aerodynamic diameter less than 10 ?m (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxide, nitric oxide (NO), ozone (O(3)), and carbon monoxide (CO) and the occurrence of congenital heart disease in the population of Northeast England (1993-2003). Each case and control was assigned weekly average (weeks 3-8 of pregnancy) of pollutant levels measured by the closest monitor to the mother's residential postcode. Using exposure as both continuous and categorical variables, logistic regression models were constructed to quantify the adjusted odds ratios of exposure to air pollutants and the occurrence of each outcome group. We found exposure to CO and NO to be ...

2011-02-17

223

Systematics of high temperature perturbation theory: The two-loop electron self-energy in QED  

International Nuclear Information System (INIS)

In order to investigate the systematics of the loop expansion in high temperature gauge theories beyond the leading order hard thermal loop (HTL) approximation, we calculate the two-loop electron proper self-energy #SIGMA# in high temperature QED. The two-loop bubble diagram of #SIGMA# contains a linear infrared divergence. Even if regulated with a nonzero photon mass M of order of the Debye mass, this infrared sensitivity implies that the two-loop self-energy contributes terms to the fermion dispersion relation that are comparable to or even larger than the next-to-leading order (NLO) contributions of the one-loop #SIGMA#. Additional evidence for the necessity of a systematic restructuring of the loop expansion comes from the explicit gauge-parameter dependence of the fermion damping rate at both one and two loops. The leading terms in the high temperature ...

2010-01-15

224

The value of cardiac catheterization and cineangiography in infantile lobar emphysema  

International Nuclear Information System (INIS)

Lobar emphysema is an uncommon cause of respiratory distress in infancy. Congenital heart disease is seen in about 20% of the patients with infantile (congenital) lobar emphysema. We described six infants with lobar emphysema. In three of them a congenital heart disease was demonstrated by cardiac catheterization and cineangiography; two had a tetralogy of Fallot with right aortic arch and the third infant a ventricular septal defect. The pulmonary angiography showed stretching of the arteries with very poor filling of the peripheral arteries and a characteristic smaller pulmonary vein in the affected lobe. In all the six patients the pulmonary artery pressure was normal. All the patients underwent lobectomy with good results. We feel that a preoperative cardiac catheterization and cineangiography is of value in this very sick group of infants. (orig.).

225

The effects of sedative music, arousal music, and silence on electrocardiography signals  

British Library Electronic Table of Contents (United Kingdom)

Introduction: Research indicates that music can affect heart rate, blood pressure, and skin conductance. Music can stimulate central emotions in the brain and release biochemical materials that change the physiologic state. We sought to compare changes in the electrical function of the heart in response to music. Method: Subjects were asked to listen to 2 types of music, namely, sedative and arousal music, in conjunction with two 30-second periods of complete silence. The experiment was conducted in 4 segments: the first and third parts were silence, and the second and fourth parts were music. First, the response to each type of music was compared with that to the preceding period of silence. Next, the responses to both types of music were compared. Finally, the response to music regardles...

2011-01-01

226

The Impact of Proactive Chronic Care Management on Hospital Admissions in a German Senior Population  

British Library Electronic Table of Contents (United Kingdom)

Abstract An increase in chronic disease prevalence is contributing to health care cost growth and decreased quality of life in industrialized nations worldwide. Inadequate management of chronic diseases is a leading cause of hospitalizations and, thus, avoidable expenditures. In this study, we evaluated the impact of nurse-delivered care calls, the primary intervention of a proactive chronic care management (CCM) program, in a population aged 65 and older in Germany. In this analysis, hospital admission rates were evaluated among program enrollees who were diagnosed with diabetes, heart failure, coronary heart disease, or chronic obstructive pulmonary disease. The Intervention group comprised those members who participated in care calls (n?=?13,486), whereas the Comparison group included e...

2011-01-01

227

Protective effects of long term dietary restriction on swimming exercise-induced oxidative stress in the liver, heart and kidney of rat  

British Library Electronic Table of Contents (United Kingdom)

In this study, we evaluated the hypothesis that long term dietary restriction would have beneficial effects on the oxidative stress and antioxidant enzyme systems in liver, heart and kidney in adult male rats undergoing different intensities of swimming exercise. Sixty male, Sprague-Dawley rats were assigned as either dietary restricted on every other week day (DR) or fed ad libitum (AL) groups, and each group was further subdivided into sedentary, endurance swimming exercise training (submaximal exercise) and exhaustive swimming exercise (maximal exercise) groups. Animals in the submaximal exercise group swam 5 days/week for 8 weeks, while maximal exercise was performed as an acute bout of exercise. In parallel with the increase in the intensity of the exercise, the degree of lipid peroxi...

2007-01-01

228

Mother and infant coordinate heart rhythms through episodes of interaction synchrony  

British Library Electronic Table of Contents (United Kingdom)

Animal studies demonstrated the powerful impact of maternal-infant social contact on the infant's physiological systems, yet the online effects of social interactions on the human infant's physiology remain poorly understood. Mothers and their 3-month old infants were observed during face-to-face interactions while cardiac output was collected from mother and child. Micro-analysis of the partners' behavior marked episodes of gaze, affect, and vocal synchrony. Time-series analysis showed that mother and infant coordinate heart rhythms within lags of less than 1s. Bootstrapping analysis indicated that the concordance between maternal and infant biological rhythms increased significantly during episodes of affect and vocal synchrony compared to non-synchronous moments. Humans, like other mamm...

2011-01-01

229

Inhibition of the heterotetrameric K++ channel KCNQ1/KCNE1 by the AMP-activated protein kinase  

British Library Electronic Table of Contents (United Kingdom)

Abstract The heterotetrameric K++-channel KCNQ1/KCNE1 is expressed in heart, skeletal muscle, liver and several epithelia including the renal proximal tubule. In the heart, it contributes to the repolarization of cardiomyocytes. The repolarization is impaired in ischemia. Ischemia stimulates the AMP-activated protein kinase (AMPK), a serine/threonine kinase, sensing energy depletion and stimulating several cellular mechanisms to enhance energy production and to limit energy utilization. AMPK has previously been shown to downregulate the epithelial Na++ channel ENaC, an effect mediated by the ubiquitin ligase Nedd4-2. The present study explored whether AMPK regulates KCNQ1/KCNE1. To this end, cRNA encoding KCNQ1/KCNE1 was injected into Xenopus oocytes with and without additional injection o...

2011-01-01

230

Histological analysis of 70-nm silica particles-induced chronic toxicity in mice  

British Library Electronic Table of Contents (United Kingdom)

Nano-sized silica is a promising material for disease diagnosis, cosmetics and drugs. For the successful application of nano-sized material in bioscience, evaluation of nano-sized material toxicity is important. We previously found that nano-sized silica particles with a diameter of 70nm showed acute liver failure in mice. Here, we performed histological analysis of major organs such as the liver, spleen, lung, kidney, brain and heart in mice, chronically injected with 70-nm silica particles for 4weeks. Histological analysis revealed hepatic microgranulation and splenic megakaryocyte accumulation in these 70-nm silica particles treated mice, while the kidney, lung, brain and heart remained unaffected. Thus, liver and spleen appear to be the major target organs for toxicity by the chronic a...

2009-01-01

231

Flow mapping for assessment of native and repaired valves  

International Nuclear Information System (INIS)

Color Doppler flow mapping (CDFM) was performed in 47 normal women ages 18-41 mean (m) 28 to determine the normal flow phenomena across each of the 4 heart valves. The group included: 15 elite marathon runners average run (ave.) 70 miles/week, heart rate (HR) 35-54 (m 45); 14 joggers ave. 40 mi/wkm HR 40-69 (m 53); and 17 controls 0 mi/wk, HR 49-93 (m 77). 2-D echo and CDFM defined the motion of each valve, including the presence of mitral valve prolapse (MVP), the ventricular inflow and outflow patterns and the presence of regurgitation.

232

Evaluation of Neonatal Membrane Oxygenators With Respect to Gaseous Microemboli Capture and Transmembrane Pressure Gradients  

British Library Electronic Table of Contents (United Kingdom)

Abstract A series of studies performed at our center demonstrates that gaseous microemboli (GME) remain a challenge in cardiac surgical procedures. Evaluation of novel oxygenators must address hemodynamic parameters and microemboli capture capability. The objective of this study is to compare two neonatal membrane oxygenators, the Quadrox i (MAQUET Cardiopulmonary AG, Hirrlingen, Germany) and the Capiox RX05 (Terumo Corporation, Tokyo, Japan), with respect to GME capture and hemodynamic energy delivery. The experimental circuit included a Maquet HL 20 heart lung machine, a Heater Cooler Unit HCU 30 (MAQUET Cardiopulmonary AG), a membrane oxygenator (Quadrox i Neonatal or Capiox RX05), and inch tubing from the COBE Heart/Lung Perfusion Pack (COBE Cardiovascular, Inc., Arvada, CO, USA). A Ca...

2010-01-01

233

Establishment of functional primary cultures of heart cells from the clam Ruditapes decussatus  

British Library Electronic Table of Contents (United Kingdom)

Heart cells from the clam Ruditapes decussatus were routinely cultured with a high level of reproducibility in sea water based medium. Three cell types attached to the plastic after 2?days and could be maintained in vitro for at least 1?month: epithelial-like cells, round cells and fibroblastic cells. Fibroblastic cells were identified as functional cardiomyocytes due to their spontaneous beating, their ultrastructural characteristics and their reactivity with antibodies against sarcomeric ?-actinin, sarcomeric tropomyosin, myosin and troponin T-C. Patch clamp measurements allowed the identification of ionic currents characteristic of cardiomyocytes: a delayed potassium current (I K?slow) strongly suppressed (95%) by tetraethylammonium (1?mM), a fast inactivating potassium current (I K?fas...

2011-01-01

234

Effects of rosiglitazone on the configuration of action potentials and ion currents in canine ventricular cells  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE In spite of its widespread clinical application, there is little information on the cellular cardiac effects of the antidiabetic drug rosiglitazone in larger experimental animals. In the present study therefore concentration-dependent effects of rosiglitazone on action potential morphology and the underlying ion currents were studied in dog hearts. EXPERIMENTAL APPROACH Standard microelectrode techniques, conventional whole cell patch clamp and action potential voltage clamp techniques were applied in enzymatically dispersed ventricular cells from dog hearts. KEY RESULTS At concentrations -10-M rosiglitazone decreased the amplitude of phase-1 repolarization, reduced the maximum velocity of depolarization and caused depression of the plateau potential. These effects d...

2011-01-01

235

Straining electrode behavior and corrosion resistance of nickel base alloys in high temperature acidic solution  

International Nuclear Information System (INIS)

Repassivation behavior and IGA resistance of nickel base alloys containing 0#approx#30 wt% chromium was investigated in high temperature acid sulfate solution. (1) The repassivation rate was increased with increasing chromium content. And so the amounts of charge caused by the metal dissolution were decreased with increasing chromium content. (2) Mill-annealed Alloy 600 suffered IGA at low pH environment below about 3.5 at the fixed potentials above the corrosion potential in 10%Na_2SO_4+H_2SO_4 solution at 598K. On the other hand, thermally-treated Alloy 690 was hard to occur IGA at low pH environments which mill-annealed Alloy 600 occurred IGA. (3) It was considered that the reason, why nickel base alloys containing high chromium content such as Alloy 690 (60%Ni-30%Cr-10%Fe) had high IGA/SCC resistance in high temperature acidic solution containing sulfate ion, is due to both the promotion of the ...

1991-08-25

236

Recent advances and developments in refractory alloys  

Energy Technology Data Exchange (ETDEWEB)

Refractory metal alloys based on Mo, W, Re, Ta, and Nb (Cb) find applications in a wide range of aerospace applications because of their high melting points and high-temperature strength. This paper, presents recent progress in understanding and applications of these alloys. Recent studies to improve the oxidation and mechanical behavior of refractory metal alloys, and particularly Nb alloys, are also discussed. Some Re structures, for extremely high temperature applications (> 2000C), made by CVD and P/M processes, are also illustrated. Interesting work on the development of new W alloys (W-HfC-X) and the characterization of some commercial refractory metals, e.g., K-doped W, TZM, and Nb-1%Zr, continues. Finally, recent developments in high temperature composites reinforced with refractory metal filaments, and refractory metal-based intermetallics, e.g., Nb{sub 3}Al, Nb{sub ...

1993-11-01

237

Preliminary Guideline for the High Temperature Structure Integrity Assessment Procedure Part I. High Temperature Structure Design Guide  

Energy Technology Data Exchange (ETDEWEB)

A preliminary guideline for the design and evaluation of LMR high temperature structure is presented based upon ASME B and PV Code, Section III, Subsection NH. The main contents of this guideline are the materials, general design, vessel, piping, core support structure, pumps, valves, fabrication, examination, and testing for the class 1 components. The ratcheting evaluation, enhanced creep assessment, welds design and evaluation, inelastic analysis approach, piping design alternatives, and bellows design method are described in appendices. A user of this guideline should follow the essential procedures and may refer to other pertinent codes, standards, laws, regulations, or other pertinent documents when this guideline does not lead to proper design of the structure. While this guideline adopts major procedures of Subsection NH, it refers to the RCC-MR and/or DDS in some amount for the items where these codes have excellency to improve this ...

2007-02-15

238

Mechanical property of superplastic-deformed ceramics by micro-indentation method  

Energy Technology Data Exchange (ETDEWEB)

A neutron irradiation test on superplastic ceramic materials at high temperature has been proposed as an innovative basic research on high-temperature engineering using the High Temperature Engineering Test Reactor (HTTR). We investigated mechanical properties, such as the hardness and Young's modulus, of ceramic specimens after superplastic deformation. The tested material was 3Y-TZP (3mol% Yttria stabilized Tetragonal Zirconia Polycrystal) which is one of the representative superplastic ceramics. The properties were measured by a microindentation method. We also studied the relationship between crystal microstructures and the mechanical properties of deformed 3Y-TZP by scanning electron microscope (SEM). The indentation test showed that the mechanical properties of the specimens were reduced to about 1/2 by 30% deformation and to about 1/4 by 150% deformation. The SEM ...

2001-03-01

239

High temperature susceptibilities of actinide monopnictides and monochalcogenides  

International Nuclear Information System (INIS)

The inverse susceptibilities of the monopnictides and monochalcogenides of the light rare earths plotted vs. temperature flatten off at high temperatures. This behaviour is well explained by van Vleck paramagnetism of the excited states of the multiplet. For almost all actinide pnictides and chalcogenides a similar flattening-off is observed. Since spin orbit coupling is much stronger than in the light rare earth compounds an analogous interpretation is not possible. Susceptibility curves for uranium compounds can be fitted by adding a temperature dependent enhanced Pauli paramagnetism to the Curie-Weiss term (modified Curie-Weiss law). The high temperature susceptibility behaviour of neptunium compounds is very similar to uranium compounds i.e. an appreciable deviation from the Curie-Weiss law is only visible for the chalcogenides. The plutonium chalcogenides show a temperature independent ...

1998-06-12

240

High temperature strengthening mechanism of hafnium carbide in a tungsten-rhenium matrix  

Energy Technology Data Exchange (ETDEWEB)

The interrelationship between the testing temperature and HfC strength increment of an arc-melted W-3.6Re-0.4HfC was determined from 1950 K to 2980 K in a vacuum of better than 1.3{times}10{sup {minus}5} Pa (10{sup {minus}7} torr). The present research was focused on the characteristic temperature at which the rapid coarsening of HfC particles occurred and the effect of the second-phase particle size on the high temperature strength properties of this material. It was found that the HfC particle strengthening was effective in a W-Re matrix up to a characteristic temperature of 2450 K in the short-term tensile test. Carbon was found to be the rate-limiting solute in the HfC particle growth. The strength of HfC strengthened alloy at temperature above 0.5 T{sub m} is proportional to the square root of particle volume fraction. The yield strengths of W-3.6Re-0.26HfC calculated based on the particle statistical distribution had good agreement with ...

1991-01-01

241

High temperature strengthening mechanism of hafnium carbide in a tungsten-rhenium matrix  

International Nuclear Information System (INIS)

The interrelationship between the testing temperature and HfC strength increment of an arc-melted W-3.6Re-0.4HfC was determined from 1950 K to 2980 K in a vacuum of better than 1.3x10"-"5 Pa (10"-"7 torr). The present research was focused on the characteristic temperature at which the rapid coarsening of HfC particles occurred and the effect of the second-phase particle size on the high temperature strength properties of this material. It was found that the HfC particle strengthening was effective in a W-Re matrix up to a characteristic temperature of 2450 K in the short-term tensile test. Carbon was found to be the rate-limiting solute in the HfC particle growth. The strength of HfC strengthened alloy at temperature above 0.5 T_m is proportional to the square root of particle volume fraction. The yield strengths of W-3.6Re-0.26HfC calculated based on the particle statistical distribution had good agreement with the experimental values from ...

1991-01-06

242

High temperature deformation behavior of AZ31 Mg alloy  

Energy Technology Data Exchange (ETDEWEB)

High temperature deformation behavior of AZ31 Mg alloy was investigated in this study on the basis of a processing map ({epsilon} {approx} 0.6). To construct a processing map, compression tests were carried out at various temperatures and strain rates. Two regions of high deformation efficiency ({eta}) were identified as: (1) a dynamic recrystallization (DRX) domain at 250 C and 1/s and (2) a superplasticity domain at 450 C and 10{sup -4}/s. The average grain size observed in the DRX region was considerably smaller (2.9{mu}m) than in any other region. In the superplastic condition, tensile elongation to failure approached to 1040%. At the high Z regions, flow softening occurred resulting from the dynamic recrystallization but below 10{sup 10} of Z value, flow hardening occurred due to the grain growth. Possible deformation mechanisms operating at high temperature were discussed in relation to the ...

2005-07-01

243

Effects of relative thickness of the duplex-treated layer on surface properties of AlSl H13 steel  

Energy Technology Data Exchange (ETDEWEB)

A duplex surface treatment technique based on calorizing and plasma nitriding was developed to improve the wear and oxidation resistance of H13 steel at high temperatures. The effects of the relative thickness of the calorized layer to the depth of plasma nitriding on the wear and oxidation properties at temperatures up to 900 C were investigated in this work. High-temperature wear tests were performed at 500 C with dry conditions in open air using a ball-on-disk type tribotest machine. Isothermal oxidation tests were performed at 900 C for up to 100 h under controlled atmosphere. The results indicated that the specimens with a calorized layer as an intermediate phase between the surface duplex layer and the base metal showed higher wear and oxidation resistance than the specimens with a nitrided layer alone. During exposure to elevated temperatures, the aluminum in the calorized layer diffused to the surface and formed an ...

1997-10-01

244

Development of in-vessel type control rod drive mechanism for marine reactor  

Energy Technology Data Exchange (ETDEWEB)

A highly reliable control rod drive mechanism (CRDM) installed inside the reactor vessel has developed for use of an advanced marine reactor. This CRDM contributes to compactness and simplicity of the reactor system, and it can eliminate the possibility of a rod ejection accident. The CRDM works in the high temperature and high pressure water - 310degC and 12 MPa, the same atmosphere as the primary loop. Driving force is produced by a synchronous motor with the rotor of a permanent magnet, which has been developed. An innovative latch mechanism using separable ball nuts can latch driving shaft connecting the control rod and de-latch it for scram. The rod position detector using a magnetostrictive wire type sensor on the principle of Wiedeman effect has been developed, accuracy of which is verified to have a detecting error within 1.2 mm. Ball bearings for thrust and radial supports in rotation have been developed to be capable of working under ...

2001-07-01

245

Development of a filler metal for Hastelloy alloy XR weldment  

Energy Technology Data Exchange (ETDEWEB)

The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. ...

1991-11-01

246

Development of a filler metal for Hastelloy alloy XR weldment  

International Nuclear Information System (INIS)

The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. ...

247

Combustion for high temperature heating process  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the high-temperature (1500/sup 0/C or higher) heating technology by combusting natural gas. The theoretical adiabatic flame temperature is 1957/sup 0/C at the theoretical air ratio and 2801/sup 0/C at the theoretical oxygen ratio. The flame temperature is increased by 40/sup 0/C every 1%-increase of oxygen up to 25% of the concentration of oxygen and by 28/sup 0/C to 30% of it. The flame temperature is increased by 37 to 38/sup 0/C every 100/sup 0/C-increase of the temperature of preheated air. The practical temperatures are significantly lower than the theoretical ones. The ceramic calciner is provided with a two-stage burner for 1600 to 1800/sup 0/C which can use also the oxygen-riched air. The glass melting furnace is operated at 1500/sup 0/C and the flat flame burner is used for a single kiln. A stabilizing burner is used for reducing the multing time for the steel making electric arc furnace. A high-temperature ...

1987-12-05

248

Advanced concept on high temperature strength based on NRIM creep data sheet; Kinzaigiken kuripu deta shito kara umareta koon kyodo no atarashii toraekat  

Energy Technology Data Exchange (ETDEWEB)

National Research Institute for Materials started in FY1966 a creep data sheet project aiming at obtaining the creep test data until 360Ms (about 11 years and half) in maximum, and has continuously been conducting the above on more than 40 kinds of heat resistant metallic materials for practical use for 30 years already as of January, 1996. The 360Ms creep rupture strength which has been aimed at by this project is the basic important strength property referred to at the time of determining design allowable stress of high temperature structural members. The Institute has published the accumulation of the test data of long range creeps lasting beyond 360Ms of the Institute as a creep data sheet, and in this article, the tremendous volume of this long range creep test data is analyzed and studied systematically, the new knowledge concerning the high temperature strength properties thereby obtained is ...

1996-05-20

249

A partitioned central solar receiver  

International Nuclear Information System (INIS)

Else of solar energy as substitute for conventional fuels at a competitive cost requires efficient conversion from solar radiation to usable forms of energy. In solar thermal or thermochemical applications, high efficiency usually re- quires high temperature and high concentration of incoming radiation. The main form of energy loss from high temperature solar central receivers is thermal emission ('re radiation'), at an effective temperature close to the maximum receiver temperature. This loss is reduced if the aperture is divided into segments, most of which are maintained at lower temperatures. A two-stage partitioned receiver demonstrating this concept is under construction at the Weizman Solar Tower. The high-temperature stage is the DIAPR (Directly Irradiated Annular Pressurized Receiver). The low-temperature stage is made of tubular cavity receivers of simpler design. ...

1996-05-01

250

High Temperature Capacitor Development  

Energy Technology Data Exchange (ETDEWEB)

The absence of high-temperature electronics is an obstacle to the development of untapped energy resources (deep oil, gas and geothermal). US natural gas consumption is projected to grow from 22 trillion cubic feet per year (tcf) in 1999 to 34 tcf in 2020. Cumulatively this is 607 tcf of consumption by 2020, while recoverable reserves using current technology are 177 tcf. A significant portion of this shortfall may be met by tapping deep gas reservoirs. Tapping these reservoirs represents a significant technical challenge. At these depths, temperatures and pressures are very high and may require penetrating very hard rock. Logistics of supporting 6.1 km (20,000 ft) drill strings and the drilling processes are complex and expensive. At these depths up to 50% of the total drilling cost may be in the last 10% of the well depth. Thus, as wells go deeper it is increasingly important that drillers are able to monitor conditions down-hole such as temperature, pressure, ...

2009-06-30

251

Utilisation of the binders prepared from coal tar pitch and phenolic resins for the production metallurgical quality briquettes from coke breeze and the study of their high temperature carbonization behaviour  

British Library Electronic Table of Contents (United Kingdom)

To reduce the cost of the formed coke briquettes which can be used as a substitute fuel to the metallurgical coke for the blast furnace from the coke breeze alternative binders and their blends were used. The high temperature behavior was investigated. The binders tested were: the nitrogen blown, air blown coal tar pitch and the blend of air blown coal tar pitch with the phenolic resins blends. The phenolic resin blends were prepared by mixing equal amount of resole and novalac. From the results, nitrogen blowing resulted in the weakest briquettes. The air blowing procedure should be preferred in place of nitrogen blowing for this purpose. When the air blown coal tar pitch was used alone as a binder, the briquettes must be cured at 200^oC for 2h, then carbonized at a temperature above 670^...

2010-01-01

252

Use of semi-detailed kinetic schemes for a study of the temperature dependence in the reforming of fuels without catalyst; L'utilisation de schemas cinetiques semi-detailles pour une etude de l'influence de la temperature dans le reformage de combustibles sans catalyseur  

Energy Technology Data Exchange (ETDEWEB)

In order to avoid the use of catalysts in the process of auto-thermal reforming, it is possible to adopt a running at high temperature. In this study are presented the results of simulations of an auto-thermal/recuperator hybrid reforming system; these results are obtained with the oxidation model of alkanes developed by Ranzi and Faravelli. An isothermal configuration at high temperature improves the hydrogen yield and avoids the formation of soots. The analysis of the powers to be furnished to assure such an experimental mode, and the global approach of the fuel cell system show that the management of the heat exchanges is a key parameter in this process. (O.M.)

2000-07-01

253

Tunneling spectra of high-temperature superconductors  

International Nuclear Information System (INIS)

The frequency dependence of the tunneling spectrum #alpha#"2F (#omega#) is analyzed in terms of electron pairing induced by exchange of acoustic plasmons in addition to the usual phonon-exchange mechanism. Analytic expressions are obtained for the electron self-energy, the tunneling function #alpha#"2F, and the electron pairing coupling lambda which determines the superconducting properties. The resulting theory is applied to recent tunneling data of Nb_3Sn in order to examine the anomalous discrepancies with the phonon density of states found by neutron scattering experiments. The results demonstrate how the high-temperature (T/sub c/ approx. 20 "0K) superconducting properties of A-15 compounds are enhanced by acoustic-plasmon contributions, and thus they reconcile these high transition temperatures with the relatively small values of the phonon part of lambda estimated from several independent experiments.

254

The effect of V and W addition on the high temperature strength properties of 12%Cr-15%Mn austenitic steels  

International Nuclear Information System (INIS)

The effect of W and V on the high temperature strength properties of 12%Cr-15%Mn austenitic steels was studied from the view point of precipitation hardening and internal stress. The contribution of W addition to the tensile and creep-rupture strength was not so large. By contrast the combined addition of W and V increased the strength considerably. These are resulted from the precipitation of fine vanadium nitride (VN) within grains and the enhancement of M_2_3C_6 type carbide precipitation at grain boundaries. The V added material had large internal stress value which is considered to be due to dislocation movement disturbed by fine vanadium nitrides. (author).

255

The basic experiment on the high-temperature chemical reaction between sodium compound and iron-base material. Pt. 2. Structure observations  

Energy Technology Data Exchange (ETDEWEB)

This experiment is carried out in the series of the investigation on the damage mechanism of carbon steel. In this paper, the damage situation is considered by structure observations. The test were carried out in 600degC-1200degC temperature range, in blowing an argon gas. The reagents are Na{sub 2}O, Na{sub 2}O{sub 2} and NaOH. From structure observations, the holes are observed on the surface of iron-base material in some test conditions. This result is indicated that the selective reaction occurs. The selective reaction is more obvious as the time exposed to the high temperature is longer. It is considered that the selective reaction occurs after the chemical reaction between iron-base material and sodium compound. The areas, in which Mn-concentration is higher, are observed in products on the surface of specimen. (author)

1997-07-01

256

Synthesis of ceramic powders by novel microwave-hydrothermal processing  

Energy Technology Data Exchange (ETDEWEB)

Microwave-hydrothermal processing was compared with conventional hydrothermal processing in the crystallization of hematite from 1M ferric nitrate and hydroxyapatite from calcium oxide and phosphoric acid. Microwave-hydrothermal processing led to the crystallization of hematite while convention-hydrothermal process led to the crystallization of a mixture of goethite and hematite under the same temperature conditions. Thus the crystallization of hematite which is the stable iron oxide phase at high temperatures has been catalyzed by microwaves. Microwave-hydrothermal processing also led to highly crystalline hydroxyapatite powders compared to the conventional hydrothermal processing which also points to the catalytic role of microwaves. The microwave induced effects may be attributed to the generation of localized high temperatures at the reaction sites which enhance reaction rates.

1996-06-01

257

Study on the crystallization behaviour and thermal stability of glass-ceramics used as solid oxide fuel cell-sealing materials  

British Library Electronic Table of Contents (United Kingdom)

Glass ceramics are commonly used as sealing materials for planar solid oxide fuel cells (SOFCs). The major requirements of stack and module builders for these materials are the stability of the coefficient of thermal expansion (CTE), excellent bonding (sticking) behaviour and the absence of volatile ingredients, which can lead to changes of the material properties and the sealing ability. SCHOTT Electronic Packaging has developed special glasses and glass-ceramics for various solid oxide fuel cell designs and operating temperatures. The glass compositions are based on the system MgO-Al2O3-BaO-SiO2-B2O3. In this study the evaluation of the developed materials was done by high temperature aging tests for up to 1000h, high temperature XRD-studies and Rietveld calculations, combined with scann...

2011-01-01

258

Structural material trends in future power plants  

Energy Technology Data Exchange (ETDEWEB)

Future power plants will be more fuel efficient, environmentally benign, and economical than current power plants. A high performance power system (HIPPS), based on a coal-fired combined cycle, is currently being developed. The corrosion and temperature-strength properties of currently available metallic materials limit the maximum efficiency of this cycle. Recently, ceramic matrix composites have shown promise in overcoming the design limitations on the future power plants. In particular, the high-temperature, and corrosion and erosion resistant properties of continuous fiber ceramic composites (CFCCs) will allow engineers to design high-temperature heat exchangers, cyclone vortex finder tubes, and other components. Research being performed to evaluate candidate materials for use in future power plants is discussed.

2000-07-01

259

Solar receiver-reactor with specularly reflecting walls for high-temperature thermoelectrochemical and thermochemical processes. Technical report  

Energy Technology Data Exchange (ETDEWEB)

A new kind of receiver-reactor for high-temperature solar furnaces is proposed. The main body of the receiver component is an ellipsoid of revolution with specularly reflecting inner walls. The reactor component, a crucible, is placed at one focal point and the aperture at the other. With this arrangement, substantially all of the incident radiation from the concentrator should reach the reactor directly or after one reflection from the cavity walls. An analysis of the radiative exchange among the surfaces is presented. The analysis provides a tool for a parametric study and optimization of the design. It is found that, in contrast to that of conventional well-insulated cavity receivers, its collection efficiency is not very sensitive to the size of its aperture.

1987-10-27

260

Sialon sintering product excellent in liquid sodium corrosion resistance  

International Nuclear Information System (INIS)

A sialon sintering product of the present invention comprises #beta#'-sialon grains and less than 2vol% of a grain boundary phase, and a relative density of the sintering product is greater than 98%. It exhibits a high temperature strength of greater than 500Mpa at 650degC and shows such high corrosion resistances that the reduction of the volume due to corrosion is less than 0.5mg/cm"2 in a liquid sodium immersion test, and the corrosion of the grain boundary is not observed. Accordingly, there can be provided a sialon sintering product excellent in corrosion resistance in a liquid sodium circumstance while keeping the high temperature strength as an excellent characteristic of the sialon sintering product. (T.M.).

1995-04-19

261

Research on Actinides in Nuclear Fuel Cycles  

International Nuclear Information System (INIS)

The electrochemical/spectroscopic integrated measurement system was designed and set up for spectro-electrochemical measurements of lanthanide and actinide ions in high temperature molten salt media. A compact electrochemical cell and electrode system was also developed for the minimization of reactants, and consequently minimization of radioactive waste generation. By applying these equipment, oxidation and reduction behavior of lanthanide and actinide ions in molten salt media have been made. Also, thermodynamic parameter values are determined by interpreting the results obtained from electrochemical measurements. Several lanthanide ions exhibited fluorescence properties in molten salt. Also, UV-VIS measurement provided the detailed information regarding the oxidation states of lanthanide and actinide ions in high temperature molten salt media

2007-04-01

262

Research and development project for flywheel energy storage system using high-temperature superconducting magnetic bearing  

Energy Technology Data Exchange (ETDEWEB)

Recent progress in yttrium-based oxide high-temperature superconductors has enabled the production of a large diameter bulk with a strong flux-pinning force. A combination of this superconductor and a permanent magnet makes it feasible to fabricate a noncontact, non-controlled superconducting magnetic bearing with a very small rotational loss, applicable to a flywheel energy storage system. A conceptual design of an 8 MWh flywheel energy storage system using the new bearing has been developed, based on measured data on a miniature bearing model, which proved to be potentially capable of achieving a high energy storage efficiency of 84 pc. A 100 W h-class experimental system was then built, which attained a high revolution rate of 17000 rpm, with a rotational loss of about 0.6 W. (authors). 2 refs., 7 figs., 3 tabs.

1995-12-31

263

Power efficiency for very high temperature solar thermal cavity receivers  

Science.gov (United States)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the solar ...

1984-01-01

264

Power efficiency for very high temperature solar thermal cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the solar ...

1984-10-30

265

Performance of high-temperature central receiver systems  

Energy Technology Data Exchange (ETDEWEB)

The development of central receiver technology for the production of electricity is reasonably well established. One possible direction for future research and development efforts funded by the Department of Energy is high-temperature, high-performance systems. In this paper, the performance of central receiver systems is investigated for a range of heliostat sizes, field configurations, plant sizes, and receiver temperatures. The maximum plant efficiency achievable in a central receiver system that uses simple cavity geometry is shown for a range of receiver temperatures. The impact of changes in heliostat size, field packing density, and canting and focusing strategies on system efficiency are investigated over a range of plant sizes. The results of the study underscore the importance of accommodating high absorber plane fluxes in order to efficiently produce working temperatures at or above 1200/sup 0/C.

1984-07-01

266

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

267

Neutron physical investigations on the shutdown effect of small boronated absorbing spheres for pebble-bed high-temperature gas-cooled reactors  

Energy Technology Data Exchange (ETDEWEB)

An emergency shutdown system for high-temperature gas-cooled pebble-bed reactors is proposed in addition to the common absorber rod shutdown system. This system is based on the strongly absorbing effect of small boronated graphite spheres (called KLAK), which trickle in case of emergency by gravity from the top reflector into the reactor core. The inner reflector of the Siemens-Argonaut reactor was substituted by an assembly of spherical Arbeitsgemeinschaft Versuchsreaktor fuel elements, and the shutdown effect was examined by installing well-defined KLAK nests inside this assembly. The purpose was to develop and prove a calculational procedure for determining criticality values for assemblies of large fuel spheres and small absorbing spheres.

1987-09-01

268

Magnetic properties of B and AB-spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Ni, Mg) materials  

Energy Technology Data Exchange (ETDEWEB)

The magnetic properties of diluted spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) systems have been studied by mean field theory, probability law and high-temperature series expansions method in the range 0 {<=} x {<=} 1. The exchange interactions are calculated by the first and second theory, respectively. The magnetic phase diagrams of Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) are calculated by the high-temperature series expansions, combined with the Pade approximants method. The critical exponent associated with the magnetic susceptibility ({gamma}) is deduced.

2010-08-06

269

Influence of pH on electrochemical properties of passive films formed on Alloy 690 in high temperature aqueous environments  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on Alloy 690 in different pH solutions at high temperatures were studied by potentiodynamic polarization, Auger electron spectroscopy, thermodynamic diagrams and the Mott-Schottky relation. The chemical compositions and electronic structures of the passive films were found to be strongly pH-dependent. In alkaline solutions, a secondary passivation was clearly observed on potentiodynamic polarization curves. The passive films were a mixture of Cr{sub 2}O{sub 3} and FeCr{sub 2}O{sub 4} below the flat band potential of nickel oxide and were NiFe{sub 2}O{sub 4} above this potential. Electronic structure models, describing the electrochemical properties of the passive films, are proposed and discussed.

2009-12-15

270

Influence of pH on electrochemical properties of passive films formed on Alloy 690 in high temperature aqueous environments  

International Nuclear Information System (INIS)

Passive films formed on Alloy 690 in different pH solutions at high temperatures were studied by potentiodynamic polarization, Auger electron spectroscopy, thermodynamic diagrams and the Mott-Schottky relation. The chemical compositions and electronic structures of the passive films were found to be strongly pH-dependent. In alkaline solutions, a secondary passivation was clearly observed on potentiodynamic polarization curves. The passive films were a mixture of Cr2O3 and FeCr2O4 below the flat band potential of nickel oxide and were NiFe2O4 above this potential. Electronic structure models, describing the electrochemical properties of the passive films, are proposed and discussed.

2009-12-01

271

Improved power efficiency for very-high-temperature solar-thermal-cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positiond in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts radiation from the front of the absorber. With this arrangement, a high percentage of the solar power input ...

1982-04-14

272

High-temperature property data: Ferrous alloys  

Energy Technology Data Exchange (ETDEWEB)

In this book over 250 alloys are organized by AISI number into 10 major sections: Irons, Carbon Steels, Alloy Steels, Low Alloy Constructional Steels, Ultra High Strength Steels, Tool Steels, Maraging Steels, Wrought Stainless Steels, Heat Resistnat Casting Alloys, and Iron Based Rought Superalloys. Each alloy record lists the designation, specifications, UNS number, composition, product forms and a comment on the high-temperature properties and applications. Referenced data is then given for physical properties such as density, specific heat, thermal conductivity, thermal expansion, electrical conductivity, Poisson's ratio, moduli of elasticity and rigidity, etc. Mechanical properties follow, and include tensile properties, shearing and bearing properties, impact properties, creep, stress rupture and stress relaxation and fatigue properties. The last part of the alloy record gives other effects of temperature, such as hot hardness, corrosion, and growth.

1987-01-01

273

High-temperature low-cycle fatigue and tensile properties of Hastelloy X and alloy 617 in air and HTGR-helium  

Energy Technology Data Exchange (ETDEWEB)

Results of strain controlled fatigue and tensile tests are presented for two nickel base solution hardened alloys which are reference structural alloys for use in several high temperature gas cooled reactor concepts. These alloys, Hastelloy X Inconel 617, were tested at temperatures ranging from room temperature to 871/sup 0/C in air and impure helium. Materials were tested in the solution annealed as well as in the pre-aged condition where aging consisted of isothermal exposure at one of several temperatures for periods of up to 20,000 h. Comparisons are also given between the strain controlled fatigue lives of these alloys and several other commonly used alloys all tested at 538/sup 0/C.

1981-01-01

274

High-temperature hysteretic electronic effects of (Al{sub x}Ga{sub 1{minus}x}){sub 0.5}In{sub 0.5}P (x > 0.65)  

Science.gov (United States)

The authors have studied (Al{sub x}Ga{sub 1{minus}x}){sub 0.5}In{sub 0.5}P doped with tellurium using deep level transient spectroscopy and associated electrical measurements. Several defect states are observed in the upper half of the band gap, that are believed to be intrinsic to the alloy system as well as related to the tellurium donors. Defects observed at measurement temperatures above 390 K exhibit a hysteretic behavior. The observed spectra depend on the biasing conditions applied to the Schottky diode during cooling. The hysteretic behavior suggests the existence of different defect configurations, which can be accessed under conditions of high temperatures and electrical stress, but remain stable below 300 K.

2000-02-01

275

High-temperature hysteretic electronic effects of (Al{sub x}Ga{sub 1{minus}x}){sub 0.5}In{sub 0.5}P (x > 0.65)  

Energy Technology Data Exchange (ETDEWEB)

The authors have studied (Al{sub x}Ga{sub 1{minus}x}){sub 0.5}In{sub 0.5}P doped with tellurium using deep level transient spectroscopy and associated electrical measurements. Several defect states are observed in the upper half of the band gap, that are believed to be intrinsic to the alloy system as well as related to the tellurium donors. Defects observed at measurement temperatures above 390 K exhibit a hysteretic behavior. The observed spectra depend on the biasing conditions applied to the Schottky diode during cooling. The hysteretic behavior suggests the existence of different defect configurations, which can be accessed under conditions of high temperatures and electrical stress, but remain stable below 300 K.

2000-02-01

276

High-specific-output diesel engines  

Energy Technology Data Exchange (ETDEWEB)

The diesel engine is the most efficient device for converting chemical energy stored in liquid hydrocarbon fuels into useful work. Up to 50% of the energy in the fuel is converted into output shaft work. The modern diesel engine is twice as efficient as the early diesel engines and produces as much as sixty times as much power for a given cylinder size. These developments have, in recent years, been accompanied by a substantial reduction in the noxious elements in the exhaust gas so that engines are now, relatively speaking, ecologically clean. The developments have centred around exhaust gas turbocharging and improved fuel injection systems, but recent work on low-heat-rejection engines has resulted in significant advances in structural ceramics and in high-temperature lubricating oil, as well as an enhanced understanding of heat transfer in high-temperature combustion chambers. (author).

1991-01-01

277

High temperature structural silicides  

Energy Technology Data Exchange (ETDEWEB)

Structural silicides have important high temperature applications in oxidizing and aggressive environments. Most prominent are MoSi{sub 2}-based materials, which are borderline ceramic-intermetallic compounds. MoSi{sub 2} single crystals exhibit macroscopic compressive ductility at temperatures below room temperature in some orientations. Polycrystalline MoSi{sub 2} possesses elevated temperature creep behavior which is highly sensitive to grain size. MoSi{sub 2}-Si{sub 3}N{sub 4} composites show an important combination of oxidation resistance, creep resistance, and low temperature fracture toughness. Current potential applications of MoSi{sub 2}-based materials include furnace heating elements, molten metal lances, industrial gas burners, aerospace turbine engine components, diesel engine glow plugs, and materials for glass processing.

1997-03-01

278

High temperature deformation of the Al-5Cr-2Zr alloy as a function of powder particle diameter  

International Nuclear Information System (INIS)

The powder particle size, D, influences the creep behaviour of Al-Cr-Zr alloys. The alloy studied in this work, Al-5Cr-2Zr (mass%), was prepared by argon atomization. Three size fractions of powder particles were selected: 24-50 #mu#m, 50-100#mu#m and 100-200 #mu#m in diameter. They were consolidated by extrusion. Independently of D, the flow behaviour of the alloy can be described by the power law equation. As test temperature increases, the stress exponent n decreases up to a value close to 5. A decrease of D causes an increase of n and delays the alloy degradation at high temperature. (Author) 11 refs.

1998-01-01

279

High temperature deformation behaviour of Ti-10V Alloy and associated activation energy  

International Nuclear Information System (INIS)

High temperature deformation behaviour of an experimental Beta-titanium alloy Ti-10V has been studied in the temperature range 800 to 945 degree C by using the method of crosshead speed cycling. Although subgrain formation was observed but the alloy did not exhibit superplastic behaviour in the entire temperature range studied. A very large initial grain size and elongation of grains during the deformation are considered the main factors responsible for absence of superplastic behaviour. The activation energy values for regions II and III of the ln sigma vs. ln small epsilon plots are close to the lower of the two activation energy values proposed together to describe self diffusion in beta-phase suggesting that the rate controlling mechanism is that for lattice diffusion rather then grain boundary diffusion. (author)

2004-06-01

280

Hardening effect in Ti-3Al-2.5V during high temperature deformation  

International Nuclear Information System (INIS)

High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-2.5V has been investigated in the temperature range 830 deg. C to 910 deg. C by using the method of cross head speed cycling. On the basis of flow stress-strain rate and strain rate sensitivity data, it was found that the alloy exhibits a hardening effect in the entire temperature range studied, amount of hardening being significant at the highest test temperature of 910 deg. C which resulted in a degradation of superplastic properties of the alloy. Grain growth in beta-phase due to strain was considered responsible for the hardening effect observed.

281

HYFIRE: a tokamak- high-temperature electrolysis system  

Energy Technology Data Exchange (ETDEWEB)

Brookhaven National Laboratory is involved in a conceptual design study of a commercial nuclear power system which utilizes high-temperature electrolysis to produce synthetic fuels. The system is called HYFIRE. It includes a tokamak fusion power reactor supplying electrical and thermal energy to an array of electrolytes. The electrolytes produce hydrogen which can be used either directly as a fuel or in the production of hydrocarbons. The purpose of the study is to provide a mechanism for DOE to further assess the commercial potential of fusion using a tokamak reactor to produce synthetic fuel. The HYFIRE design is based on the tokamak commercial power reactor, STARFIRE. STARFIRE uses the deuterium/tritium/lithium fuel cycle. The HYFIRE study assumes the plasma shape and characteristics of STARFIRE study but uses a different blanket design. This study is particularly interested in the possibility of using the STARFIRE tokamak in the production of synthetic fuels.

1980-01-01

282

Geometry effects in the pulsed magnetization of high-temperature superconductor bulk parts  

International Nuclear Information System (INIS)

The dynamic response of cylindrical and ring-shaped YBaCuO bulk parts to pulsed magnetic fields is calculated by using small sets of finite elements. Some comparisons with experimental results are provided, and they give confidence in the modelling of the superconducting properties. Transient magnetizations as a function of time and space as well as shapes and absolute values of trapped magnetic flux profiles are presented. The influence of the sample geometry is investigated for different millisecond pulsed magnetization processes. Results are reported for different radial thicknesses and heights, different pulse durations, peak magnetic fields and pulse sequences with and without stepwise cooling. Comparisons concerning the achievable trapped magnetic field and flux are made, and implications for the use of high-temperature superconductor bulk parts as cryo-permanent magnets in potential applications like electric machinery are discussed.

2005-02-01

283

Filler metal development for Hastelloy alloy XR. Filler metal for hastelloy alloy XR structure with thick wall  

Energy Technology Data Exchange (ETDEWEB)

In order to develop the filler metal for Hastelloy alloy XR structure with thick wall, the weldability and high temperature strength properties of Hastelloy alloy XR weldment were investigated using the filler metals, which were alloy-designed on the basis of multiple regression analysis. The former was examined through the chemical analysis in the deposited metal, bend test, FISCO cracking test, optical microscopy and hardness measurement. The latter was investigated by means of tensile and creep test. It was found from these results that the crack susceptibility in the weldment was apparent to be lowered without degrading the high temperature strength properties. Therefore, it is concluded that these filler metals possess excellent performance as the filler metal for Hastelloy alloy XR structure with thick wall. (author).

1991-11-01

284

Experimental Investigations into Phosphoric Acid Adsorption on Platinum Catalysts in a High Temperature PEM FuelCell  

British Library Electronic Table of Contents (United Kingdom)

Abstract Dynamic testing of a phosphoric acid-based high temperature PEM fuel cell shows a peculiar phenomenon. A certain current loss is observed after temperature cycling at constant voltage. This loss is incidentally recovered by applying a cell voltage spike to open circuit voltage. Experimental investigations into temperature, cell voltage, and ageing effects show that this phenomenon might occur due to the orientation of the adsorbed phosphate species on the platinum catalyst surface. Along with some supporting literature and experimental results, a hypothesis is presented in order to explain this occurrence. Phosphoric acid adsorption hysteresis on platinum catalyst due to temperature cycling could cause the temporary cell current loss. Electrode potential-dependent molecule symmetr...

2011-01-01

285

EPR and luminescence studies of Eu(II) magnetically diluted in LiCl-KCl salt  

Energy Technology Data Exchange (ETDEWEB)

High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu{sub 2}O{sub 3} as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.

2007-12-15

286

EPR and luminescence studies of Eu(II) magnetically diluted in LiCl-KCl salt  

International Nuclear Information System (INIS)

High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu_2O_3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.

2007-12-01

287

EPR and luminescence studies of Eu(II) magnetically diluted in LiCl-KCl salt  

British Library Electronic Table of Contents (United Kingdom)

High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723K by using Eu2O3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.

2007-01-01

288

Development of ball bearings with solid film for high-vacuum, high-temperature, high-speed application  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the experimental results of long-life solid lubricated ball bearings tested under high-vacuum of 10 exp -4 Pa, high-temperature of 300 C, and high-speed (9000 rpm) conditions. For full ball-type bearings, the thin soft metals, either Ag or Pb, which were coated on the races and balls, appeared to have good torque properties. However, the durability of such bearings was less than 300 hours. The transfer films from the lamellar solid MoS2 and metal composite retainers improved the torque and wear properties. For ceramic, i.e., silicon nitride, balls used with steel rings, wear occurred on the inner rings. All ceramic bearings with composite retainers showed improved torque and wear properties. 18 refs.

1993-04-01

289

Detection of Fluorescence for Lanthanides in LiCl-KCl Molten Salt Medium  

Energy Technology Data Exchange (ETDEWEB)

In the electrorefining step of the pyrochemical process, actinide ions dissolved in the LiCl-KCl eutectic salt are recovered as pure actinide metals at a cathode for a re-use as a nuclear fuel from the aspect of its nonproliferation of the nuclear fuel cycles. The lanthanide species dissolved in the LiCl-KCl eutectic salt play an important role in an effective metal purification during the electrorefining step, so it is necessary to understand the chemical and physical behaviors of lanthanides in molten salt. The in situ spectroscopic measurement system and studies according to temperature changes are essential for better understandable information. To our knowledge, the absorption studies of lanthanides at high temperatures have been reported before, but the fluorescence studies of those at high temperature are not reported yet. We will discuss here the fluorescence behaviors of lanthanides in LiCl-KCl ...

2007-10-15

290

Detection of Fluorescence for Lanthanides in LiCl-KCl Molten Salt Medium  

International Nuclear Information System (INIS)

In the electrorefining step of the pyrochemical process, actinide ions dissolved in the LiCl-KCl eutectic salt are recovered as pure actinide metals at a cathode for a re-use as a nuclear fuel from the aspect of its nonproliferation of the nuclear fuel cycles. The lanthanide species dissolved in the LiCl-KCl eutectic salt play an important role in an effective metal purification during the electrorefining step, so it is necessary to understand the chemical and physical behaviors of lanthanides in molten salt. The in situ spectroscopic measurement system and studies according to temperature changes are essential for better understandable information. To our knowledge, the absorption studies of lanthanides at high temperatures have been reported before, but the fluorescence studies of those at high temperature are not reported yet. We will discuss here the fluorescence behaviors of lanthanides in LiCl-KCl ...

2007-10-01

291

Creep performance and microstructure of the iron alloy Alloy 800 HT  

International Nuclear Information System (INIS)

The examination of the high-temperature properties of the alloy Alloy 800HT has shown that both the creep performance and the microstructure of the material can be purposefully set by the initial heat treatment. At the high temperatures applied, (700-900 C), a rapid softening process sets in induced by carbide precipitation, stabilization, and coarsening. This softening process causes creep velocities strongly accelerating as a function of duration of the heat treatment prior to the creep test. The identified cause of the softening effect is a change in particle size that could be verified by SEM and TEM. It is shown that two different carbide precipitate size classes are responsible for the softening effect. While the precipitates dectable by TEM become effective primarily via interactions with dislocations, the carbide precipitates detectable only by SEM contribute to a hardening of the grain boundaries and the ...

1997-11-28

292

Corrosion behaviour of Alloy 800 in high temperature aqueous solutions: Electrochemical studies  

International Nuclear Information System (INIS)

The anodic behaviour and passivity breakdown of Alloy 800 in aqueous solutions of sodium chloride, sodium sulphate and sodium bicarbonate were studied by electrochemical techniques in the temperature range from 60 C to 280 C. The pitting resistance and pitting morphology of the alloy in chloride plus sulphate and chloride plus bicarbonate mixtures, at 60 C and 280 C, were also examined. Increasing bicarbonate or sulphate additions to chloride solutions shift the characteristic pitting potential of Alloy 800 to higher values, both at low and high temperatures. Changes in pitting morphology were observed in sulphate containing solutions while the morphology of the attack found in bicarbonate containing solutions was similar to that in pure chloride solutions. Finally, no localized or substantial generalized corrosion was detected in pure sulphate or bicarbonate solutions at any temperature. (orig.).

293

Atomic processes in high temperature plasmas  

International Nuclear Information System (INIS)

Much theoretical and experimental efforts have been expended in recent years to study those atomic processes which are specially relevant to understanding high temperature laboratory plasmas. For magnetically confined fusion plasmas, the temperature range of interest spans from the hundreds of eV at plasma edges to 10 keV at the center of the plasma, where most of the impurity ions are nearly fully ionized. These highly stripped ions interact strongly with electrons in the plasma, leading to further excitation and ionization of the ions, as well as electron capture. Radiations are emitted during these processes, which easily escape to plasma container walls, thus cooling the plasma. One of the dominant modes of radiation emission has been identified with dielectronic recombination. This paper reviews this work.

1990-01-01

294

Alloy 800 specifications in compliance with component requirements  

Energy Technology Data Exchange (ETDEWEB)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...

1990-04-01

295

Alloy 800 specifications in compliance with component requirements  

International Nuclear Information System (INIS)

In view of the importance of the material Alloy 800 in high-temperature reactor plants (HTR), a material data bank was established which is used for statistical evaluation of mechanical and physical material behaviour. Based on investigations on the interconnection between the mechanical properties at high temperatures and the metallurgical parameters, different types of Alloy 800 were specified in compliance with the component requirements. In addition, aspects of corrosion and toughness behaviour were taken into consideration. The specifications and strength characteristics for the different variants of Alloy 800 were incorporated into draft DIN standards after discussion and approval in expert committees. Further important characteristics of the mechanical and physical material behaviour were summarized in HTR material data sheets so as to furnish an improved basis for the design and stress analyses of Alloy 800 ...

296

Activation energy for high temperature deformation of Ti-10V alloy on the basis of second strain rate cycles  

International Nuclear Information System (INIS)

Activation energy values for high temperature deformation of a beta -titanium alloy Ti-10V were determined from the flow stress strain rate data taken from the second increasing strain rate cycles, in order to find the rate controlling mechanism. Although the data obtained from first increasing strain rate cycles are considered most appropriated by the author in a previous study due to obvious reasons, the values obtained in present work are again indicative of lattice self diffusion in beta -phase as the rate controlling mechanism for this alloy and nevertheless suggest that two different activation energy values for a deformation process could be possible in a given temperature range, depending upon the data. (author)

2007-12-01

297

Study of the origin of elements of the uranium-235 family observed in excess in the vicinity of the experimental nuclear EL4 reactor under dismantling. Lessons got at this day and conclusions; Etude de l'origine des elements de la famille de l'uranium-235 observes en exces dans les environs du reacteur nucleaire experimental EL4 en cours de demantelement. Enseignements retires a ce jour et conclusion  

Energy Technology Data Exchange (ETDEWEB)

This study resumes the discovery of an excess of actinium 227 found around by EL4 nuclear reactor actually in dismantling. The search for the origin of this excess revealed a real inquiry of investigation during three years. Because a nuclear reactor existed in this area a particular attention will have concerned this region. The doubt became the line of conduct to find the answer to the human or natural origin of this excess. Finally and against any evidence, it appears that the origin of this phenomenon was natural, consequence of the particular local geology. The detail of the different investigations is given: search of a possible correlation with the composition of elevations constituent of lanes, search (and underlining) of new sites in the surroundings of the Rusquec pond and the Plouenez station, study of the atmospheric deposits under winds of the nuclear power plant and in the east direction, search of a possible relationship with the gaseous effluents of ...

2007-07-01

298

Optical Properties and Wave Propagation in Semiconductor-Based Two-Dimensional Photonic Crystals  

Energy Technology Data Exchange (ETDEWEB)

This work is a theoretical investigation on the physical properties of semiconductor-based two-dimensional photonic crystals, in particular for what concerns systems embedded in planar dielectric waveguides (GaAs/AlGaAs, GaInAsP/InP heterostructures, and self-standing membranes) or based on macro-porous silicon. The photonic-band structure of photonic crystals and photonic-crystal slabs is numerically computed and the associated light-line problem is discussed, which points to the issue of intrinsic out-of-lane diffraction losses for the photonic bands lying above the light line. The photonic states are then classified by the group theory formalism: each mode is related to an irreducible representation of the corresponding small point group. The optical properties are investigated by means of the scattering matrix method, which numerically implements a variable-angle-reflectance experiment; comparison with experiments is also provided. The analysis of surface ...

2002-12-31

299

Northeast U.S. LNG project expansions : are they competing or complementary projects?  

Energy Technology Data Exchange (ETDEWEB)

The Northeast Gateway Energy Bridge Deepwater Port project was commissioned in 2005 and is based on a proprietary energy bridge shipboard regasification technology. The offshore liquefied natural gas (LNG) facility will be located in federal waters 13 miles southeast of Gloucester and was designed to cope with the extreme weather of the Massachusetts Bay. A dual-buoy system will be capable of ensuring continuous delivery of natural gas. Throughput capacity will range from 400 to over 800 MMcf/d. Vessels used at the port have capacities of 138,000 m{sup 3} and 150,900 m{sup 3} with peak sendout rates of 600 MMcf/d. The vessels have the capacity to rapidly increase and decrease their delivery rates. During periods of peak demand, 2 vessels can be simultaneously accommodated at the port, which has been designed to accommodate larger vessels to maximize future throughput. This presentation presented details of the port's design phases and the review processes undertaken to gain ...

2006-07-01

300

Energy in Asia. An Outline of Some Strategic Energy Issues in Asia  

Energy Technology Data Exchange (ETDEWEB)

The Asian countries are expected to generate 45% of the world energy consumption and Japan is the absolutely greatest consumer in Asia, but China is the country that will be most important as a new consumer on the world energy markets. China, like India and later possibly even Japan try to change to natural gas as a source of energy as much as possible. This is causing a competition about the resources that can be reached by pipelines for gas, which in practice means those in Russia and Central Asia. Russia is trying to control the gas in Central Asia. The competition is also increasing about oil. China is becoming heavily dependent on Muslim countries in the Middle East and Central Asia. This also leads to an effort to increase the safety along the sea lanes, which may collide with the interests of other countries. Territorial conflicts with gas and oil as underlying elements exist in Asia. USA is a player on the energy market, who is using military means as well, ...

2003-01-01

301

DETECTION OF A PSEUDOBULGE HIDDEN INSIDE THE 'BOX-SHAPED BULGE' OF NGC 4565  

International Nuclear Information System (INIS)

Numerical simulations show that box-shaped bulges of edge-on galaxies are not bulges: they are bars seen side-on. Therefore, the two components that are seen in edge-on Sb galaxies such as NGC 4565 are a disk and a bar. But face-on SBb galaxies always show a disk, a bar, and a (pseudo)bulge. Where is the (pseudo)bulge in NGC 4565? We use archival Hubble Space Telescope H-band images and Spitzer Space Telescope 3.6 #mu#m wavelength images, both calibrated to Two Micron All Sky Survey K_s band, to penetrate the prominent dust lane in NGC 4565. We find a high surface brightness, central stellar component that is clearly distinct from the boxy bar and from the disk. Its brightness profile is a Sersic function with index n = 1.55 #+-# 0.07 along the major axis and 1.33 #+-# 0.12 along the minor axis. Therefore, it is a pseudobulge. It is much less luminous than the boxy bar, so the true pseudobulge-to-total luminosity ratio of the galaxy is PB/T = 0.06 #+-# 0.01, much ...

2010-06-01

302

Superoxide production by NAD(P)H oxidase and mitochondria is increased in genetically obese and hyperglycemic rat heart and aorta before the development of cardiac dysfunction. The role of glucose-6-phosphate dehydrogenase-derived NADPH  

UK PubMed Central (United Kingdom)

Increased oxidative stress is a known cause of cardiac dysfunction in animals and patients with diabetes, but the sources of reactive oxygen species [e.g., superoxide anion (O2)]...Full Text Available

2009-07-01

303

Spectroscopic, Structural, and Functional Characterization of the Alternative Low-Spin State of Horse Heart Cytochrome c  

UK PubMed Central (United Kingdom)

The alternative low-spin states of Fe3+ and Fe2+ cytochrome c induced by SDS or AOT/hexane reverse micelles exhibited the heme group in a less...Full Text Available

2008-05-15

304

Prevent Diabetes Problems: Keep Your Heart and Blood Vessels Healthy  

Science.gov (United States)

... mini-stroke," also called a TIA or a transient ischemic attack . If you have any of these warning signs, ... ur-uhl) (ar-TEE-ree-uhl) (dih-ZEEZ) transient ischemic attack (TRANZ-see-uhnt) (iss-KEE-mik) (uh-TAK) [ ...

305

Physical activity at work and job responsibility as risk factors for fatal coronary heart disease and other causes of death.  

UK PubMed Central (United Kingdom)

Altogether 99 029 men aged 40-59, employed on the Italian railroad system, were classified in three levels of physical activity at work and three levels of job responsibility and then followed up for...Full Text Available

1985-12-01

306

Patient Monitoring during Mechanotherapy Based on Electrocutaneous Impedance Measurement  

British Library Electronic Table of Contents (United Kingdom)

Patient monitoring during mechanotherapy based on electrocutaneous impedance measurement is discussed. Methods implemented by the Alpharhythmica computer-assisted system are described. Mechanotherapy modifies electrocutaneous impedance as compared to other parameters: heart rate, arterial pressure, and body temperature. Real time criteria of mechanotherapy efficacy based on electrocutaneous impedance measurement are suggested. Results of electrocutaneous impedance monitoring are presented.

2011-01-01

307

New steam heart for the Pernis refinery [in the Netherlands]; Nieuw stoomhart voor Pernis  

Energy Technology Data Exchange (ETDEWEB)

The Construction of a natural gas-fired combined heat and power plant at the site of the Pernis refinery will further reduce the emission of SO2 and NOx. [mk]. [Dutch] Met de bouw van een aardgasgestookte warmte/kracht-installatie op het terrein van de raffinaderij Pernis wordt de emissie van SO2 en NOx verder gereduceerd.

2009-05-15

308

New insights in LV torsion for the selection of cardiac resynchronisation therapy candidates  

British Library Electronic Table of Contents (United Kingdom)

Recent literature indicates that torsion of the left ventricle (LV) is a promising predictor for response to cardiac resynchronisation therapy (CRT). Among patients with severe heart failure, 45 to 75% of patients show rigid body rotation, where the base and apex rotate in the same direction, instead of normal, opposite rotation. The occurrence of this phenomenon seems to be a good indicator for response to CRT. From this review, it can be concluded that LV torsion might be a welcome addition to current selection criteria.

2011-01-01

309

National Renewable Energy Laboratory 2005 Research Review  

Energy Technology Data Exchange (ETDEWEB)

Science and technology are at the heart of everything we do at the National Renewable Energy Laboratory, as we pursue innovative, robust, and sustainable ways to produce energy--and as we seek to understand and illuminate the physics, chemistry, biology, and engineering behind alternative energy technologies. This year's Research Review highlights the Lab's work in the areas of alternatives fuels and vehicles, high-performing commercial buildings, and high-efficiency inverted, semi-mismatched solar cells.

2006-06-01

310

Mapping of the nucleotide-binding sites in the ADP/ATP carrier of beef heart mitochondria by photolabeling with 2-azido[#alpha#-"3"2P]adenosine diphosphate  

International Nuclear Information System (INIS)

2-Azido[#alpha#-"3"2P]adenosine diphosphate (2-azido[#alpha#-"3"2P]ADP) has been used to photolabel the ADP/ATP carrier in beef heart mitochondria. In reversible binding assays carried out in the dark, this photoprobe was found to inhibit ADP/ATP transport in beef heart mitochondria and to bind to two types of specific sites of the ADP/ATP carrier characterized by high-affinity binding (K/sub d/ = 20 #mu#M) and low-affinity binding (K/sub d/ = 400 #mu#M). In contrast, it was unable to bind to specific carrier sites in inverted submitochondrial particles. Upon photoirradiation of beef heart mitochondria in the presence of 2-azido[#alpha#-"3"2P]ADP, the ADP/ATP carrier was covalently labeled. After purification, the photolabeled carrier protein was cleaved chemically by acidolysis or cyanogen bromide and enzymatically with the Staphylococcus aureus V8 protease. In the ADP/ATP carrier protein, which is 297 amino acid residues ...

311

Kappa-opioid receptor activation during reperfusion limits myocardial infarction via ERK1/2 activation in isolated rat hearts  

UK PubMed Central (United Kingdom)

BackgroundWe investigated whether p42/p44 extracellular signal-regulated kinases (ERK1/2) and/or phosphatidylinositol-3-OH kinase (PI3K)-Akt play a crucial role in cardioprotection...Full Text Available

2011-05-01

312

Increased levels of the calcification marker Matrix Gla Protein and the inflammatory markers YKL-40 and CRP in patients with type 2 diabetes and ischemic heart disease  

UK PubMed Central (United Kingdom)

Objective and designLow grade inflammation is of pathogenic importance in atherosclerosis and in the development of cardiovascular disease (CVD) and type 2 diabetes (T2D). Matrix...Full Text Available

313

Improved Mobilization of the CD34+ and CD133+ Bone Marrow-Derived Circulating Progenitor Cells by Freshly Isolated Intracoronary Bone Marrow Cell Transplantation in Patients with Ischemic Heart Disease  

UK PubMed Central (United Kingdom)

Cell therapy is a promising novel option for treatment of cardiovascular disease. Because the role of bone marrow-derived circulating progenitor cells (BM-CPCs) after cell therapy is less clear, we...Full Text Available

2011-09-01

314

Efficacy and tolerability of 0.5% timolol maleate ophthalmic gel-forming solution QD compared with 0.5% levobunolol hydrochloride BID in patients with open-angle glaucoma or ocular hypertension.  

Science.gov (United States)

We compared the efficacy of timolol maleate ophthalmic gel-forming solution 0.5% QD with that of levobunolol hydrochloride 0.5% BID, as measured by change in intraocular pressure (IOP), effect on heart rate, and ocular tolerability. The study had a positive-controlled, double-masked, randomized, multicenter, 12-week, two-period (6 weeks each), crossover design. One hundred fifty-two patients with open-angle glaucoma or ocular hypertension were randomized to receive either timolol maleate gel-forming solution QD or levobunolol BID for 6 weeks, followed by a crossover to the alternate treatment. IOP and heart rate were measured at morning trough and peak during weeks 3, 6, 9, and 12. Timolol maleate gel-forming solution QD was comparable to levobunolol BID in reducing IOP at peak and trough. Although the effects on peak heart rate were similar between the two medications, the effect on trough heart rate ...

315

Check-Up America: Know Your Risk, Lower Your Risk for Diabetes and Heart Disease  

Medline Plus

... Cholesterol High Blood Glucose High Blood Pressure Overweight Physical Activity Small Steps for Your Health Smoking Age, ... blood pressure, unhealthy cholesterol, and high blood glucose. Physical Activity Staying active helps manage your blood glucose, ...

316

Catestatin (chromogranin A344-364) is a novel cardiosuppressive agent: inhibition of isoproterenol and endothelin signaling in the frog heart  

UK PubMed Central (United Kingdom)

The catecholamine release-inhibitory catestatin [Cts; human chromogranin (Cg) A352-372, bovine CgA344-364] is a vasoreactive and anti-hypertensive peptide derived...Full Text Available

2008-07-01

317

Assessment of Glucagon-Like Peptide-1 Analogue and Renin Inhibitor on the Binding and Regulation of GLP-1 Receptor in Type 1 Diabetic Rat Hearts  

UK PubMed Central (United Kingdom)

This study focuses on the effects of long-term renin-angiotensin system suppression and/or incretin mimetic therapies on the regulation and binding affinity of GLP-1 to its receptor in the coronary...Full Text Available

2011-01-01

318

Advances in sensor technology  

Energy Technology Data Exchange (ETDEWEB)

During thirty years the techniques used for sensing the environment have changed dramatically. This paper describes the latest generation of sensors available. This new generation of sensors includes those two most critical gas sensors for methane and carbon monoxide and new sensors for airflow and air temperature. When these sensors are combined with the new sensors for machine condition monitoring it forms the heart of the Sentex system. 2 figs.

1989-06-01

319

A region in the cytosolic domain of the epidermal growth factor receptor antithetically regulates the stimulatory and inhibitory guanine nucleotide-binding regulatory proteins of adenylyl cyclase.  

UK PubMed Central (United Kingdom)

Epidermal growth factor (EGF) stimulates adenylyl cyclase in the heart via activation of the stimulatory GTP-binding protein Gs. Therefore, employing peptides corresponding to regions in the cytosolic...Full Text Available

1995-03-14

320

Use of (high temperature) ammoniated citric acid for boiler chemical cleaning  

Energy Technology Data Exchange (ETDEWEB)

Georgia Power`s primary boiler cleaning solvent in the past has been hydrochloric acid. Citric acid has recently been used on two boilers in an effort to move to a safer and more environmentally acceptable cleaning solvent. As with any change, there is a learning curve and the (new) cleaning process has to be proven with regard to process consistency and cleaning effectiveness. This paper describes our experiences with citric acid along with comparisons of past hydrochloric acid cleanings.

1995-01-01

321

Thermal dissolution of mechanically activated Barzas sapromyxite coal with benzene under supercritical conditions  

British Library Electronic Table of Contents (United Kingdom)

The results of the thermal dissolution of Barzas sapromyxite coal in benzene under supercritical conditions in a flow system are reported. It was found that the mechanical pretreatment of coal under intense impact bending conditions resulted in an increase in the yield and a change in the group composition of the liquid products: in the high-temperature region of the process, the concentration of high-molecular-weight components (preasphaltenes, asphaltenes, and resins) increased.

2011-01-01

322

The development and testing of emissivity enhancement coatings for thermophotovoltaic (TPV) radiator applications  

Energy Technology Data Exchange (ETDEWEB)

One requirement of a thermophotovoltaic (TPV) radiator is to efficiently emit photons at high temperatures to TPV cells for conversion to electric power. Because many candidate radiator materials with adequate structural properties display low emissivity, coatings or other surface modifications are required for enhancement of emissivity. Six plasma sprayed coatings and one textured surface demonstrated adequate thermal stability and emittance values of 0.8 or greater. Promising attributes of modified surfaces are identified.

1999-03-01

323

Study on carbonization of spherical fuel elements for 10 MW high temperature gas-cooled reactor  

International Nuclear Information System (INIS)

The principle for working out the time-temperature schedule of the carbonization was determined through the investigation on the carbonization process of the green body and the phenol formaldehyde resin. During the carbonization process, the crack at lower temperatures is due to strain inhomogeneity produced in press. But the crack at higher temperatures results from the improper increasing rate of temperature. The application of the autoclave-carbonization process can increase the mechanical properties of the spherical fuel elements.

324

Study of transient enhanced dopant diffusion in silicon and proposed limiting methods  

International Nuclear Information System (INIS)

The transient enhanced diffusion in crystalline silicon implanted with dopants ad followed by high temperature annealing to activate the dopants is introduced. The physical mechanisms of transient enhanced dopant diffusion are then reviewed together with a short introduction to the proposed suppressing methods. Finally, the perspectives with using high energy heavy ions in this field are briefly discussed

2001-09-01

325

Structural instability and superconductivity in A-15 compounds  

International Nuclear Information System (INIS)

Structural instabilities are now being found in many high-temperature superconductors. Compounds with the A-15 (#beta#-W) structure comprise the most important group of these materials, and their properties have been extensively studied for over 15 years. A review is given of some of these results, particularly those relating to the elastic behavior. The empirical relation of the structural instability and the anharmonicity to the high superconducting transition temperature is discussed.

326

Strength of VT22 titanium alloy in various structural states  

International Nuclear Information System (INIS)

The influence of heat treatment on the structure, mechanical properties and fracture peculiarities of high-strength (#alpha#+#beta#)-titanium alloy VT22 has been studied. It is ascertained that thermal cycling and subsequent high-temperature aging permit to reduce considerably crack growth rate. Thermal cycling is realized in the following mode: heating in #beta#-region, cooling and allowance in (#alpha#+#beta#)-region, heating in #beta#-region.

327

Statistical mechanics and thermodynamics for tachyons  

International Nuclear Information System (INIS)

Momentum- and speed-dependent Maxwell-Boltzmann equilibrium distributions have been derived for tachyons and compared with the corresponding relativistic distributions. This is followed by a calculation of the mean, most probable and r.m.s. speeds for both the relativistic and tachyonic distributions. The ideal gas of tachyons is discussed, including calculations of the internal energy and entropy. In each case a comparison is made with the corresponding bradyonic results. It is found that tachyons behave just like bradyons in the high-temperature limit, but have markedly different behaviour at low temperatures.

328

Researches on Plasma Physics and Controlled Fusion in IPP NSC KIPT  

International Nuclear Information System (INIS)

Recent results of experimental and theoretical investigations, carried out in the Institute of plasma Physics of the NSC KIPT, are presented in the report. The main problems of discussion are as follows: plasma confinement and heating in stellarators and electromagnetic traps; powerful quasi-steady-state plasma accelerators (QSPA); experiments relevant for ITER; fusion Plasma theory; methods of high temperature plasma diagnostics; plasma technology. The main prospects on the IPP investigators are discussed also.

2006-01-01

329

Reactivity of ceramic superconductors with palladium alloys  

Science.gov (United States)

This paper reports Palladium alloy compositions investigated for suitability as a nonreactive material for the processing of ceramic superconductors. Barium-based superconductors were tested on Pd-Au and Pd-Ag alloys for reactivity. Bismuth-based superconductors were tested on a Pd-Ag alloy. The least reactive was found to be 70% Pd-30% Ag for the barium-based high-temperature superconductors (HTSC), whereas 30% Pd-70% Ag was found to be least reactive for bismuth-based HTSC.

1990-06-01

330

Radiative Heat Transfer Augmentation in High Temperature Combustion Systems with Application to Radiant Tube Burners. Final Report, April 1987-March 1990.  

Science.gov (United States)

Gas fired radiant tube heaters provide an indirect heating source for applications in which direct contact cannot be permitted between combustion gases and the workpiece. The program was an investigation of ways to improve performance of such burners thro...

1990-01-01

331

Powder metallurgical high performance materials. Proceedings. Volume 3: general topics  

International Nuclear Information System (INIS)

The proceedings of these seminars form an impressive chronicle of the continued progress in the understanding of refractory metals and cemented carbides and in their manufacture and application. The 15"t"h Plansee Seminar was convened under the general theme 'Powder Metallurgy High Performance Materials'. Under this broadened perspective the seminar will strive to look beyond the refractory metals and cemented carbides, which remain at its focus, to novel classes of materials, such as intermetallic compounds, with potential for high temperature applications. (boteke)

2001-05-01

332

Non-destructive measurement of corrosion effects on high temperature coatings  

Energy Technology Data Exchange (ETDEWEB)

Non-destructive methods for measuring the remaining anticorrosive or antioxidative ability of coatings are investigated. For anticorrosive chromium coatings the increasing ferromagnetism caused by loss of chromium is measured by a permeability probe. Measured values on blades after operation are correlated with the progress of corrosion as determined by metallographic methods. For antioxidative aluminum coatings the diminishing layer thickness is taken as indication for the exhaustion of their protection ability. The layer thickness is measured eddy current probes, especially developed for this application.

1990-01-01

333

Mechanism of denting corrosion  

International Nuclear Information System (INIS)

The rapid corrosion of carbon steels in high temperature, acid chloride solutions is shown to be rate limited by the anodic reaction, 3Fe + 4H_2O = Fe_3O_4 + 8H"+ + 8e"-, based on experiments which find that the corrosion rate in 0.1M NiCl_2 solution has an activation energy of 60 kJ/ mole and is unaffected by adding NaCl or by replacing NiCl_2 with PtCl_4. (author).

334

Measurement of the susceptibility of solid "3He along the melting curve from 20 mK down to the nuclear ordering temperature  

International Nuclear Information System (INIS)

The susceptibility of solid "3He is deduced from multiple echoes observed in pulsed NMR experiments. It follows a Curie Weiss law at high temperature, increases faster than this law below 5 mK and drops abruptly around 1 mK. (Auth.).

1977-02-01

335

Long-term high temperature fatigue properties of new structural materials for nuclear reactors  

Energy Technology Data Exchange (ETDEWEB)

This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10{sup -6}/s and its experimental verification could be carried out. And, it was ...

2003-01-01

336

Long-term high temperature fatigue properties of new structural materials for nuclear reactors  

International Nuclear Information System (INIS)

This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10"-"6/s and its experimental verification could be carried out. And, it was also ...

2003-01-01

337

Koyo engineering journal, No. 147, April 1995. Special issue on automotive bearings and applicable products  

Energy Technology Data Exchange (ETDEWEB)

Special Issue on Automotive Bearings and Applicable Products; Reports include Performance of Ceramic Cam Roller Follower for Automotive Engine; Performance of Drawn Cup Needle Roller Bearing for Propellershaft; Plastic Bearing Retainer for High Temperature Oil Lubrication; Bearing Device for Vehicle Axle; and Flush Mounting Type Programmable Cam Switches.

1995-12-31

338

Joining of technical ceramics  

International Nuclear Information System (INIS)

Large, complex, high purity ceramic shapes are required by a variety of emerging technologies for their electrical insulation and high temperature strength properties coupled with their refractoriness and purity. Ceramic sealant bonding, using crystalline and vitreous sealant materials, has recently shown significant potential for joining technical ceramics to form the required shapes. Materials and techniques for joining technical ceramics including alumina, magnesia, zirconia and thoria are discussed. (orig.).

339

Investigation of corrosion experienced in a spray calciner/ceramic melter vitrification system  

Energy Technology Data Exchange (ETDEWEB)

After periodic testing of a large-scale spray calciner/ceramic melter vitrification system over a 2-yr period, sufficient corrosion was noted on various parts of the vitrification system to warrant its disassembly and inspection. A majority of the 316 SS sintered metal filters on the spray calciner were damaged by chemical corrosion and/or high temperature oxidation. Inconel-601 portions of the melter lid were attacked by chlorides and sulfates which volatilized from the molten glass. The refractory blocks, making up the walls of the melter, were attacked by the waste glass. This attack was occurring when operating temperatures were >1200/sup 0/C. The melter floor was protected by a sludge layer and showed no corrosion. Corrosion to the Inconel-690 electrodes was minimal, and no corrosion was noted in the offgas treatment system downstream of the sintered metal filters. It is believed that most of the melter corrosion occurred during one ...

1980-08-01

340

Highly efficient ion source for analysis of transuranium elements  

Energy Technology Data Exchange (ETDEWEB)

Results are described of the study of the analytical applicability of a highly efficient ion source developed for a mass spectrometer. Its ionizer is in the form of a partially closed cavity with a small aperture for leading out ions, heated to a high temperature. The new ion source increases the sensitivity of the apparatus in operations with transuranium elements by almost two orders of magnitude. It is possible to perform isotopic analyses with a high salt content in the sample, and to study the characteristics of nuclear fuel, even without chemical separation of the sample elements.

1987-01-01

341

High temperature strength properties of Mod.9Cr-1Mo steel forging weld zone  

International Nuclear Information System (INIS)

In the feasibility study on commercialized FBR systems, the application of 12Cr steel, with its physical properties and high-temperature strength properties, as structural material is considered in order to greatly reduce construction costs by compacted instruments and structures. In this report, creep, fatigue and the creep-fatigue properties of Mod.9Cr-1Mo steel forging (thickness 550mm) weld, representing conventional steels, were evaluated in order to obtain the needed basic data for the evaluation of the high-temperature strength of 12Cr steel weld. The results obtained are as follows: (1) Metal suitable for HAZ was made by applying thermal treatment to simulate the thermal hysteresis during welding to clearly define creep and fatigue properties in a HAZ softened zone. (2) Creep strength of the weld metal and the welded joint was equal to that of the base metal. However, the welded joint ruptured in the HAZ softened zone and its ductility ...

342

High temperature materials experience at the Central Receiver Test Facility  

Science.gov (United States)

During four years of operation at the Central Receiver Test Facility (CRTF) ceramics have performed well in cyclic solar flux densities of less than 30 W/cm/sup 2/. Above 100 W/cm/sup 2/, serious limitations exist. Important application considerations include: the geometry, cyclic and long time exposures, flux density gradients, thermal shock, weathering, and soiling.

1982-01-01

343

High temperature liquid level sensor  

International Nuclear Information System (INIS)

A length of metal sheathed metal oxide cable is perforated to permit liquid access to the insulation about a pair of conductors spaced close to one another. Changes in resistance across the conductors will be a function of liquid level, since the wetted insulation will have greater electrical conductivity than that of the dry insulation above the liquid elevation.

1983-03-01

344

High temperature electrochemical polishing of H{sub 2}S from coal gasification process streams. Quarterly progress report, April 1, 1995--June 30, 1995  

Energy Technology Data Exchange (ETDEWEB)

This program is concerned with the development of an advanced method for the separation of hydrogen sulfides from coal gas. The process utilizes an electrochemical membrane which removes hydrogen sulfide without cooling the gas and with negligible pressure loss through the separator.

1996-02-01

345

HTR looking forward to his future with confidence  

International Nuclear Information System (INIS)

The days of high-temperature reactors in the Federal Republic of Germany are numbered. The AVR has been decommissioned, and an application has been filed for licensing the decommissioning of the THTR. Nevertheless, Prof. Dr. Rudolf Schulten who is the director of Juelich Nuclear Research Center's Institute for Reactor Development, and also full professor of Aachen Technical University in the field of reactor safety, predicts a good future for the HTR reactor line on a worldwide level, due to the inherent safety of this reactor type. (orig.).

346

Fabrication of a 275/sup 0/C geothermal temperature tool  

Energy Technology Data Exchange (ETDEWEB)

The fabrication of a Prototype 275/sup 0/C Geothermal Temperature Tool is reviewed. This tool fabrication uses hybrid circuits that were developed at Sandia National Laboratories and are now being built at Teledyne Philbrick. To achieve high-temperature operation, the standard military specification hybrid technology was modified in fabrication processes and materials.

1981-01-01

347

Electronic instabilities and phonon softening in A-15 compounds  

International Nuclear Information System (INIS)

The structural instability in high temperature A-15 superconductors is examined from a phenomenological, Landau theoretic point of view, based on the picture of an electronically driven lattice instability. emphasis is given to lattice properties--in particular, the extended softening of phonons in k-pace and phonon linewidth. Implications of the extended softening on the microscopic picture of the transition, and the interplay between structural and superconducting instabilities in the A-15 compounds are discussed.

348

Effect of mating surface on the high temperature wear of 253 MA alloy  

Energy Technology Data Exchange (ETDEWEB)

The wear behaviour of metallic material is influenced by the friction force, which in turn, is governed by the hardness and oxidation kinetics of the mating surface. In view of this, present investigation is undertaken to find the influence of mating surface on the high temperature wear of 253 MA alloy. This alloy is developed for high temperature application. In this work 253 MA alloy is made to slide against two different types of counter face material, namely 100Cr6 steel and PM 1000 alloy, at five different temperatures. 100Cr6 steel gets soften with increase of temperature whereas PM 1000 alloy retains its strength even at high temperature. The friction coefficient and the thickness loss of 253 MA alloy is measured and compared against both variety of mating surfaces as function of temperatures. The morphology of the worn surfaces and the transverse section ...

2004-04-01

349

Dynamic recrystallization behavior of a directionally solidified superalloy  

Energy Technology Data Exchange (ETDEWEB)

This paper investigates the dynamic recrystallization behavior of a directionally solidified (DS) nickel-base superalloy. The dynamic recrystallization occurs after the uncoated superalloy has been tested by tensile creep at elevated temperature for a long time. The dynamic recrystallization temperature is slightly lower than that of the static recrystallization. The dynamic recrystallization behavior of the DS superalloy below the static recrystallization temperature is mainly related to the high temperature oxidation and the free surface. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

2007-10-15

350

Development of zirconium alloys. Part II  

Science.gov (United States)

A number of alloys of zirconium have been investigated as part of a program aimed at improving the high-temperature tensile and creep strength of zirconium. These alloys include aluminum, beryllium, lead, magnesium, molybdenum, niobium, tantalum, tin, titanium, tungsten, vanadium, and zinc, binary and ternary alloys. The data indicate that aluminum, lead, molybdenum niobium, tin, titanium, tungsten, and vanadium can be used successfully to harden zirconium, and that aluminum, tin, titanium, and vanadium are particularly effective in maintaining the strength of zirconium at elevated temperatures.

1952-01-02

351

Determination of Y, Ba and Cu in superconductor films by x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide x-ray fluorescence analysis was used for the determination of Y, Ba and Cu in thin high-temperature superconducting films. Atomic emission ICP spectrometry was used to estimate the precision and accuracy of analytical results. Reasonable agreement between both methods was obtained when a polynomial calibration curve was applied. (author) 4 refs.; 4 tabs.

1994-06-01

352

Ceramic dome receiver technology developments  

Energy Technology Data Exchange (ETDEWEB)

The development and experimental demonstration of a high-temperature seal for the SHARE ceramic dome cavity receiver is reported. The mechanical contact seal which was tested on one-foot-diameter silicon-carbide ceramic-dome hardware at pressure differentials to four atmospheres and dome temperatures to 2200/sup 0/F (1200/sup 0/C) showed negligible leakage at expected receiver operating conditions. Potential solar receiver applications for the technology are illustrated.

1980-01-01

353

Carbide transformations in a gamma/gamma-prime nickel alloy during prolonged aging  

Energy Technology Data Exchange (ETDEWEB)

Carbide reactions occurring in a precipitation-hardening gamma/gamma-prime Ni-Cr alloy during prolonged high-temperature aging are investigated experimentally. It is found that the decomposition of primary MC carbides, which is accompanied by the precipitation of M23C6 particles, may lead to void nucleation and growth. The effect of carbide transformations on the residual properties of the material at temperatures above the equicohesion temperature is observed at the late stages of aging only. 6 references.

1988-08-01

354

A new high-temperature solar research furnace  

Energy Technology Data Exchange (ETDEWEB)

A new highly concentrating solar research furnace has recently been completed at the University of Minnesota. The experimentally observed flux concentration ratio, at small aperture, of a cavity receiver is about 7000. The furnace embodies features which may be of interest to others in the solar energy community. This paper describes its construction and performance.

1983-08-01

355

A modeling study by response surface methodology and artificial neural network on culture parameters optimization for thermostable lipase production from a newly isolated thermophilic Geobacillus sp. strain ARM  

UK PubMed Central (United Kingdom)

BackgroundThermostable bacterial lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other...Full Text Available

356

26 years of operating experience with a boiler drum manufactured from a high-temperature copper-nickel-molybdenum steel. 26 Jahre Betriebserfahrungen mit einer Kesseltrommel aus einem warmfesten Kupfer-Nickel-Molybdaen-Stahl  

Energy Technology Data Exchange (ETDEWEB)

The creep behaviour of boiler drums of CuNiMo steels depends on the ratio of the alloys, the heat treatment and the processing technology. Reduction in deformability must be expected but, under optimum conditions, this does not lead to a critical material condition. The appropriate material tests are indispensable. (orig.)

1993-05-01

357

Usefulness of myocardial imaging by [sup 123]I-MIBG in assessment of diabetic neuropathy  

Energy Technology Data Exchange (ETDEWEB)

In diabetic patients with autonomic neuropathy, it is suggested that there is a reduced uptake of [sup 123]I-metaiodobenzylguanidine (MIBG) in the heart. We compared the difference of myocardial [sup 123]I-MIBG accumulation between 4 diabetic patients with triopathy and 6 patients without it. In all 10 patients, coronary angiography and [sup 201]Tl imaging (rest and 4 hours later) were performed. [sup 123]I-MIBG (111 MBq) was administered intravenously and its imaging was recorded on 15 minutes and 4 hours after injection. In all 4 cases with triopathy, [sup 123]I-MIBG imaging showed defect in apical and inferior region. In 2 out of 6 cases without triopathy, rapid clearance was noticed in apical and inferior region. There was no significant stenosis in right coronary artery and no defect in initial and delayed [sup 201]Tl images in all cases. We concluded that diabetic autonomic neuropathy in the heart was prominent in apical and inferior ...

1993-10-01

358

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 muscarinic receptor analogs for ...

359

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 various muscarinic receptor analogs for ...

1988-10-15

360

Natriuretic peptides in the pathophysiology of congestive heart failure.  

Science.gov (United States)

A hallmark of congestive heart failure (CHF) is the activation of the cardiac endocrine system, in particular atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The natriuretic peptides are a group of structurally similar but genetically distinct peptides that have diverse actions in cardiovascular, renal, and endocrine homeostasis. ANP and BNP are of myocardial cell origin and C-type natriuretic peptide (CNP) is of endothelial origin. ANP and BNP bind to the natriuretic peptide-A receptor (NPR-A), which, via 3',5'-cyclic guanosine monophosphate (cGMP), mediates natriuresis, vasodilatation, renin inhibition, antimitogenesis, and lusitropic properties. CNP lacks natriuretic actions but possesses vasodilating and growth inhibiting actions via the guanylyl cyclase-linked natriuretic peptide-B receptor. All three peptides are cleared by the natriuretic peptide-C receptor and degraded by the ectoenzyme neutral endopeptidase 24.11, both of which are ...

2000-05-01

361

Magnetic resonance imaging in patients with heart valve prostheses  

International Nuclear Information System (INIS)

Artifical valve prostheses are often regarded as a contraindication for magnetic resonance imaging (MRI), although preliminary in vitro studies suggested, that patients with these metallic implants might safely undergo MR examination. This study reports on the experience with a group of 89 patients with 100 heart valve prostheses who were examined by spin-echo MR and gradient-echo MR. MR examination was performed in all patients without complications. The spin-echo sequence showed advantages in the depiction of anatomical structures like paravalvular abcesses. Anatomical structures adjacent to the artificial valve were clearly visivle and the metal components of the valves showes no or only small artifacts. Artifacts were accentuated when using gradient-echo sequences. Gradient-echo sequences provided valuable information regarding the presence of valvular insufficiency. Physiological valvular regurgitation was easy to differentiate from pathological paravalvular ...

362

Kinetics of nucleotide transport in rat heart mitochondria studied by a rapid filtration technique  

Energy Technology Data Exchange (ETDEWEB)

A rapid filtration technique has been used to measure at room temperature the kinetics of ADP and ATP transport in rat heart mitochondria in the millisecond time range. Transport was stopped by cessation of the nucleotide supply, without the use of a transport inhibitor, thus avoiding any quenching delay. The kinetics of ({sup 14}C)ADP transport in energized mitochondria were apparently monophasic. The rate of transport of ({sup 14}C)ATP in energized mitochondria was 5-10 times lower than that of ({sup 14}C)ADP. Upon uncoupling, the rate of ({sup 14}C)ATP uptake was enhanced, and that of ({sup 14}C)ADP uptake was decreased. However, the two rates did not equalize, indicating that transport was not exclusively electrogenic. Transport of ({sup 14}C)ADP and ({sup 14}C)ATP by resting mitochondria followed biphasic kinetics. Depletion of nucleotides in resting mitochondria resulted in a greater decrease in the extent of the slow phase than of the rapid one. In addition, ...

1990-10-01

363

Digital luminescent radiography: A substitute for conventional chest radiography?  

International Nuclear Information System (INIS)

The image quality of digital luminescent radiography (DLR) is sufficient for routine biplane chest radiography and for follow-up studies of heart size, pulmonary congestion, coin lesions, infiltrations, atelectasis, pleural effusions, and mediastinal and hilar lymph node enlargement. Chest radiography in the intensive care unit may in most cases be performed using the DLR technique. there is no need for repeat shots because of incorrect exposure, and the position of catheters, tubes, pacemakers, drains and artificial heart valves, the mediastinum, and the retrocardiac areas of the left lung are more confidently assessed on the edge-enhanced DLR films than on conventional films. Nevertheless, DLR is somewhat inferior to conventional film-screen radiography of the chest as it can demonstrate or rule out subtle pulmonary interstitial disease less confidently. There is no reduction of radiation exposure of the chest in DLR compared with modern ...

364

Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard  

Energy Technology Data Exchange (ETDEWEB)

The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a ...

2009-04-15

365

Production of "9"9Tc"m radiopharmaceuticals for brain, heart and kidney imaging. Final report of a co-ordinated research programme 1991-1994  

International Nuclear Information System (INIS)

The report contains highlights of the achievements of the IAEA Co-ordinated Research programme on Evaluation on the Use of Bulk Reagents for the Production of "9"9Tc_m Radiopharmaceutical and Kits, the participants' summary reports (Argentina, Chile, Greece, India, Indonesia, Japan, Malaysia, Portugal, Russian Federation, Thailand, Uruguay, United States of America), recommended product protocols for five compounds and the participants' recommendations regarding continued support and further directions of co-ordinated research work. Refs, 6 figs, 8 tabs, 6 schemes.

1990-06-24

366

Placental transfer of 14C-hexoprenaline. [Rabbits  

Energy Technology Data Exchange (ETDEWEB)

The placental transfer of a single intravenous injection of 14C-hexoprenaline was studied in eight pregnant New Zealand white rabbits. Maternal and fetal blood was sampled intermittently for 60 minutes after the injection. An initial rapid decrease in the levels of 14C-hexoprenaline in maternal blood was followed by a second slower phase, whereas fetal levels remained insignificant. The conclusion, therefore, is that the rapid improvement in fetal heart rate after the administration of a single maternal intravenous injection of hexoprenaline in the treatment of fetal distress is due to the action on the uterus and/or on maternal cardiovascular function, and not to direct stimulation of the fetus.

1982-02-01

367

Placental transfer of 14C-hexoprenaline  

International Nuclear Information System (INIS)

The placental transfer of a single intravenous injection of 14C-hexoprenaline was studied in eight pregnant New Zealand white rabbits. Maternal and fetal blood was sampled intermittently for 60 minutes after the injection. An initial rapid decrease in the levels of 14C-hexoprenaline in maternal blood was followed by a second slower phase, whereas fetal levels remained insignificant. The conclusion, therefore, is that the rapid improvement in fetal heart rate after the administration of a single maternal intravenous injection of hexoprenaline in the treatment of fetal distress is due to the action on the uterus and/or on maternal cardiovascular function, and not to direct stimulation of the fetus.

1982-02-01

368

NAME=\\  

Wastenet

...The RSPB: Birds by family: Owls E-mail to a friendE-newsletterContact us Home England Northern Ireland Scotland Wales About Overview Awards & recognition Contact ...Birds by family PrintHome Birds and wildlife Bird guide Birds by family Owls Owls Owls are specialised birds with round heads and rather flat ...or dished faces, with forward-facing eyes and a short, hooked bill. Most are nocturnal or crepuscular (active at dawn and dusk)... Owls are found all over the temperate and tropical parts of the world. Barn owl With heart shaped face, buff back ...

369

Isolated laevocardia and corrected transposition of the great vessels with total situs inversus  

International Nuclear Information System (INIS)

Isolated laevocardia combined with corrected transposition of the great arteries and complete situs inversus is rare. Due to discordant interrelationships between atria and ventricles and between ventricles and great arteries, both anomalies result in a normal circulation. In the presented case no associated cardiac malformations were present and the 55-year-old woman remained symptom-free for a long time until she developed an acquired valve disease. A systematic approach to chamber localisation in complex morphologic lesions of the heart is reviewed, and the value of CT, which can be applied successfully in older children and adults is demonstrated. (orig.).

370

Incidental discovery of asplenia syndrome, with situs inversus and a normal heart by radionuclide biliary imaging. A case report  

International Nuclear Information System (INIS)

/sup 99m/Tc biliary imaging was performed on a 34-year-old woman who was being investigated for suspected cholelithiasis. A left-sided liver was detected. On subsequent radionuclide imaging, partial visceral situs inversus and asplenia were demonstrated. Extensive roentgenographic investigation, ECG, echocardiogram, and laparotomy confirmed the radionuclide findings. Asplenia syndrome may exist without cardiovascular abnormalities and thus be undiscovered. Radionuclide imaging is important in the diagnosis of this syndrome.

371

In vitro investigation of biological and technical prosthetic heart valves in MRI: evaluation of possible deflection and heating of the implants; In-vitro-Untersuchung von biologischen und technischen Herzklappenprothesen im MRT: Beurteilung moeglicher Anziehung und Erhitzung der Implantate  

Energy Technology Data Exchange (ETDEWEB)

Purpose: In vitro evaluation of possible deflection and heating of present-day prosthetic heart valves, 12 technical and 5 biological, were investigated using a 1.5 Tesla Siemens Vision system. Deflection was measured at the edge of a 1.5 Tesla superconducting magnet. Each valve was then submerged in a vial of a 1/1 electrolyte solution and temperature was measured before and after imaging with a turbo-spin-echo sequence (TR 5200 ms, TE 138 ms, Flip angle 180 C, acquisition time 10.5 minutes, length of echo train 29). MR imaging was performed with phase encoding parallel and perpendicular to the plane of the valves. Results: None of the investigated prosthetic heart valves was deflected. The maximal observed temperature rise was 0.5 C. During MR investigation of the prostheses, artifacts caused by metallic parts were less evident using a spin-echo sequence than a gradient-echo sequence. Conclusions: Patients with the tested present-day ...

2000-02-01

372

The Protective Effect of Antioxidants on Oxidative Stress in Rats Exposed to the 950 MHz Electromagnetic Field  

International Nuclear Information System (INIS)

Studies have linked cell phone radiation to health problems such as headaches, high blood pressure, cancer and more. There is a latency period for most diseases and it may take years and more studies before the required weight of evidence is established. But the effects are cumulative and precautions should be taken now before it is too late. The aim of the present study was to investigate if supplementation with antioxidants would protect heart and liver tissues from harmful radiation emitted by cell phone. Thirty two male albino rats were randomly divided into four equal groups: I- Control, II- Antioxidants treated group, III- 950 MHz EMR, IV- 950 MHz EMR + antioxidants. A 950 MHz EMR radiation (217-Hz pulse rate, 2-W maximum peak power, SAR Specific Absorption Rate"1.6 W/Kg) was applied to groups III and IV 60 min/day, for 30 days using an experimental exposure device. Antioxidants supplement (Vitamins A, E and C + Se) was administered to rats daily, by gavages, ...

373

Study on the distribution of P-32 in chicken  

Energy Technology Data Exchange (ETDEWEB)

Radioactive phosphorus (P-32) was injected to the chicken in the purpose of determination of the uptake and distribution, as related to sex and hour differences of the various organs of the body. 2..mu..Ci of P-32 were injected to each chicken and the distribution of P-32 was observed at 1 hr, 6 hrs, 12 hrs, 24 hrs and 48 hrs after injection. In this experiment 34 heads of chicken were used (30 chicken for P-32, 4 chicken for control group) and the results obtained as follows: 1. The uptake of P-32 per gram of various organ in g. mm, femur (1 hr), liver, femur, tibia (24 hrs) and tibia (48 hrs) exhibited higher in the male than the female. 2. The uptake of P-32 per gram of various organ in heart, kidney, ovary (1 hr), kidney, brain (24 hrs) and kidney (48 hrs) exhibited higher in the female than the male. 3. The uptake ratio of brain, spleen, g. mm and tibia were increased gradually by the 12 hrs after injection of P-32, but decreased in liver, ...

1981-12-01

374

Abnormal cardiovascular responses induced by localized high power microwave exposure  

Energy Technology Data Exchange (ETDEWEB)

A hypothesis of microwave-induced circulatory under perfusion was tested in ketamine anesthetized rats whose heart rate, mean arterial pressure, pulse pressure, respiration rate, and body temperatures were monitored continuously. Fifty-eight ventral head and neck exposures in a waveguide consisted of sham-exposure and exposure to continuous wave (CW) and pulsed 1.25 GHz microwaves for 5 min. The 0.5 Hz and 16 Hz pulsemodulated microwaves were delivered at 400 kW peak power. The CW microwaves were 2 and 6.4 W. The average specific absorption rate was 4.75 W/kg per watt transmitted in the brain and 17.15 W/kg per watt transmitted in the neck. Respiration rate and mean arterial pressure were not altered. Changes in heart rate and pulse pressure were observed in rats exposed to higher power but not to the lower average power microwaves. Depression of pulse pressure, an indication of a decrease in stroke volume, and increased or decreased ...

1992-05-01

375

Wear properties of steel plasma nitrided at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

The wear behaviour of 722M24 (En40B) steel plasma nitrided at high temperatures for long durations was investigated. Under dry sliding and abrasive-containing lubricated conditions, the wear characteristics of the steel were studied as a function of load, time and white layer thickness. The white layer and the wear debris were characterized by X-ray diffraction. The topography of the wear surface was examined in a scanning electron microscope. The plasma nitriding process was carried out using a 20 kW plasma processing unit in cracked ammonia atmosphere. Treatment times of up to 100 h were employed with temperatures of 550, 570 and 590 C. Wear tests were performed with plasma nitrided AMS 6472 as the counterface material. The tests under abrasive-containing lubricated conditions were carried out with 10% carborundum powder 10 [mu]m in size in SAE-30 machine oil. The wear resistance of the steel was improved by plasma nitriding and the abrasive ...

1993-08-30

376

Vapor phase lubrication of a Ni-based superalloy  

Energy Technology Data Exchange (ETDEWEB)

In addition to ceramics, alloys such as tool steel and nickel- and iron-based superalloys are being considered for high temperature applications such as missile bearings and low heat rejection engines. Studies were made to lubricate a nickel-based superalloy at 500{degrees}C, by using a vaporized aryl phosphate ester, at a concentration of 0.1% in air. From deposition and wear studies it was found that it was impossible to form a good polymeric coating on the superalloy surface. Energy dispersive X-ray analyzer (EDXA) analysis showed that this was due to minute quantities of aluminum in the alloy segregating to the surface, upon being heated to 500{degrees}C, forming a passive oxide coating. It was necessary to activate the surface, in order to lubricate the material successfully. A method of activation by electrodepositing the surface with a layer of iron oxide was developed. Once activated, a good lubricous polymer was formed on the ...

1995-03-01

377

Use of a temperature-initiated passive cooling system (TIPACS) for the modular high-temperature gas-cooled reactor cavity cooling system (RCCS)  

Energy Technology Data Exchange (ETDEWEB)

A new type of passive cooling system has been invented (Forsberg 1993): the Temperature-Initiated Passive Cooling System (TIPACS). The characteristics of the TIPACS potentially match requirements for an improved reactor-cavity-cooling system (RCCS) for the modular high-temperature gas-cooled reactor (MHTGR). This report is an initial evaluation of the TIPACS for the MHTGR with a Rankines (steam) power conversion cycle. Limited evaluations were made of applying the TIPACS to MHTGRs with reactor pressure vessel temperatures up to 450 C. These temperatures may occur in designs of Brayton cycle (gas turbine) and process heat MHTGRs. The report is structured as follows. Section 2 describes the containment cooling issues associated with the MHTGR and the requirements for such a cooling system. Section 3 describes TIPACS in nonmathematical terms. Section 4 describes TIPACS`s heat-removal capabilities. Section 5 analyzes the operation of the temperature-control mechanism ...

1994-04-01

378

The influence of prior ageing on creep damage development in two variants of Alloy 800  

Energy Technology Data Exchange (ETDEWEB)

The influence of high temperature thermal ageing treatments on the development of intercrystalline creep damage in two variants of Alloy 800 has been investigated. Ageing up to 3000 h and creep testing were carried out at 800 and 900 C. The high temperature behaviour of the 800HT variant is discussed with reference to the effect of heat treatments on the microstructure. The metallographic methods by which the creep damage was quantitatively determined are described. The growth rate of intercrystalline microcracks was described using a statistical model and the dependence of crack growth rate on the thermal history for both 800HT and 800H was determined. The carbide precipitation and growth processes were determined as functions of the exposure temperature and duration. The results showed the three characteristic stages, precipitation, growth and coarsening (Ostwald ripening). The largest increase in the ...

1997-06-01

379

The formation mechanism of textured YBa sub 2 Cu sub 3 O sub 7-. delta  

Energy Technology Data Exchange (ETDEWEB)

The formation of textured YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (123) from a liquid phase according to the peritectic reaction Y{sub 2}BaCuO{sub 5} (211) + liquid {yields} 123 was analyzed using real-time analysis techniques of high-temperature X-ray diffraction, high-temperature optical microscopy, and environmental scanning electron microscopy (ESEM). Results were coupled with conventional ''post-mortem'' SEM analysis of processed samples at various stages of microstructural development. Observations of 123 formation and growth from the peritectic melt permit the conclusion that the presence of crystalline 211 primarily acts as a source of yttrium. The slow dissolution of 211 into the yttrium deficient liquid phase is the rate controlled step in the formation and growth of the textured 123, rather that its acting as a nucleation site for 123 grains as has been widely assumed. (orig.).

1992-05-20

380

The effect of nonstoichiometry of surface oxides formed during high temperature oxidation on the corrosion resistance of ferritic chromium steel  

Energy Technology Data Exchange (ETDEWEB)

The influence of surface oxides of variable composition and nonstoichiometry formed at high temperatures in air on the general corrosion resistance of ferritic chromium steel type 08H17T (Fe-17Cr-1Ti) in weak sulfuric acid has been studied. Anodic passive films formed on steel with different pretreatments have also been examined. The surface oxide of nearly stoichiometric composition formed at 300 C provides for the passive state of steel in sulfuric acid despite its depletion by chromium when compared with that for nonstoichiometric Cr-enriched oxide formed at 600 C. The dissolution and transformation of nonstoichiometric thermal surface oxide in sulfuric acid appear to take place through defect sites, {minus}Fe{sup 2+} ions, and oxygen vacancies of the n-type conductor. The passive film formed on the nonstoichiometric oxide film, which had been produced at 600 C, was found to be more susceptible to open-circuit breakdown compared to the ...

1998-07-01

381

The development of the high-temperature reactor. In memoriam Prof. Dr. rer.nat. Dr.-Ing. e.h. Rudolf Schulten  

International Nuclear Information System (INIS)

In the future even more than in the past, nuclear power will be indispensable in the present industrialized countries and in those still under development. The safe, nonpolluting, and economic supply of energy to mankind in the future includes so many different problems that the technology of the high-temperature reactor at its present level of development, and with the possibilities is offers above and beyond those provided by other, established, technologies, does not have to mark the end of some old line of development, but rather should be seen as the starting point of a development offering promise for the future. It is for this very reason that the extensive, valuable knowledge and experience accumulated in the construction, operation, and decommissioning of the AVR and THTR plants, the development of the HTR module and other variants and, last, but not least, the valuable results of projects such as PNP, NFE, and HHT, must be preserved at the research ...

382

The Efforts to Utilize High-Temperature Melting Technologies for ILLW and the Development of Guidelines for their Technical Assessment  

Energy Technology Data Exchange (ETDEWEB)

A couple of domestic institutions have been investigating the application of vitrification technology to treat low- and intermediate-level radioactive wastes in Korea. In the case that such investigations prove to be successful, it is expected that commercial vitrification plants will be constructed. The safety insuring on vitrification plants could not be compatible with criterion on radioactive waste management because the facilities are at high temperature and contain a variety of accommodations for the exhaust gases and residual products. Therefore, it is necessary to suggest a new strategy or modifications of criterion of radioactive waste management on considerations related with the vitrification technology. In order to ensure the safety of vitrification plants, a technical guideline or standard for design and operation of vitrification plants must be established too. A study on the safety assessment of vitrification plants in ...

2003-02-25

383

Studies on improvement of heat transfer characteristics in high temperature heat exchangers, (1)  

International Nuclear Information System (INIS)

Reported in this paper are the theoretical and experimental studies, with regard to the effects of radiation between walls, conducted for the improvement of heat transfer characteristics of the circular duct in high temperature heat exchangers that operate through the medium of non-radiating gases at around 1,000"0C. To study the fundamental performance of the heat transfer augmentation, the experiment was carried out using a double tube at temperatures up to 900"0C. The outer tube in a double tube was selectively heated so as to give a uniform heat flux selected of 6.5 x 10"3 and 4.6 x 10"4 kcal/m"2.h, while the inner tube was used as a radiating surface to impart the radiation heat transmitted from the outer tube. Selectively preheated air was caused to flow in an annular passage at an inlet temperature selected within 100"0C to 400"0C and with the Reynolds number of 2.9 x 10"3 to 3.5 x 10"4. The heat transfer characteristics were found to ...

1978-01-01

384

Stabilization of high-temperature antimony oxide with molybdenum incorporation. Structure of Mo-doped Sb/sub 2/O/sub 4/ by powder neutron diffraction and extended X-ray absorption fine structure spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

It has been discovered that the presence of MoO/sub 3/ lowers the ..cap alpha..-..beta.. transition in Sb/sub 2/O/sub 4/ from 935 to 850/sup 0/C with concurrent dissolution of Mo in the high-temperature (..beta..) form. The structure of Mo-doped ..beta..-Sb/sub 2/O/sub 4/ has been investigated by powder neutron diffraction, extended X-ray absorption fine structure (EXAFS) and Raman spectroscopies, and scanning-electron microscopy (SEM). Cell parameters: a = 12.0571 (12) A, b = 4.8335 (1) A, c = 5.3838 (6) A, ..beta.. = 105.579 (5)/sup 0/, monoclinic, space group C2/c, Z = 4. Combining the results of these techniques leads to the hypothesis that Mo is located interstitially within channels of electron density in the Sb/sub 2/O/sub 4/ structure with concurrent vacancy of two Sb/sup III/ atoms. There is no apparent oxygen deficiency in the resulting structure. 25 references, 6 figures, 3 tables.

1985-10-09

385

Results of in-house cone-cup testing of low to high temperature SPF-alloys  

Energy Technology Data Exchange (ETDEWEB)

Material testing of SPF-sheet is usually done with coupon hot tensile testing. The optimum range of strain rates is determined with stepped strain tests. To overcome the problem of very few available testing facilities and time consuming and costly procedure, cone cup testing has been developed since long. This test can be generated directly in the workshop, no machining of samples is necessary and it is very much related to the real SPF-process. The analysis of suitable temperature and strain rate is done by simple measurement of resulting cone height. This paper describes a unique and novel variant of the above mentioned baseline design. It provides on-line data of the actual status of the cone cup forming resulting from the applied, constant pressure. Strain rate variations as a result from texture or from the alloy-related behaviour is detectable. Thinning and ''hardening'' behaviour of different alloys up to maximum failure strain can be ...

2004-07-01

386

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 near-zero levels at 550{sup o}C. The ...

2005-12-01

387

Radial turbine development for the 100 kW automotive ceramic gas turbine  

Energy Technology Data Exchange (ETDEWEB)

The development of turbine components for the automotive 100 kW ceramic gas turbine has entered the final stage of the seven-year project and is making satisfactory progress, toward the goals. The authors attained the interim targets of the aerodynamic performances and have been carrying out tests to further improve efficiency. As for ceramic parts, they have changed the material of the turbine rotor to a new one that is excellent in long-sustained and high-temperature strength properties, and have confirmed substantial strength at high temperature through hot-spin tests. After evaluating blade-vibration stress through analyses and experiments, the authors completed an endurance evaluation at 1200 C (1473 K) TIT (Turbine Inlet Gas Temperature) and a rated speed of 100,000 rpm. The authors are now carrying out endurance tests at 1350 C (1623 K) TIT. For ceramic stationary parts, they already finished the evaluations at 1200 ...

1998-01-01

388

Process model for carbothermic production of silicon metal  

Energy Technology Data Exchange (ETDEWEB)

This thesis discusses an advanced dynamical two-dimensional cylinder symmetric model for the high temperature part of the carbothermic silicon metal process, and its computer encoding. The situation close to that which is believed to exist around one of three electrodes in full-scale industrial furnaces is modelled. This area comprises a gas filled cavity surrounding the lower tip of the electrode, the metal pool underneath and the lower parts of the materials above. The most important phenomena included are: Heterogeneous chemical reactions taking place in the high-temperature zone (above 1860 {sup o}C), Evaporation and condensation of silicon, Transport of materials by dripping, Turbulent or laminar fluid flow, DC electric arcs, Heat transport by convection, conduction and radiation. The results from the calculations, such as production rates, gas- and temperature distributions, furnace- and particle geometries, fluid ...

1995-09-12

389

Preliminary studies of coolant by-pass flows in a prismatic very high temperature reactor using computational fluid dynamics  

Energy Technology Data Exchange (ETDEWEB)

Three dimensional computational fluid dynamic (CFD) calculations of a typical prismatic very high temperature gas-cooled reactor (VHTR) were conducted to investigate the influence of gap geometry on flow and temperature distributions in the reactor core using commercial CFD code FLUENT. Parametric calculations changing the gap width in a whole core length model of fuel and reflector columns were performed. The simulations show the effects of core by-pass flows in the heated core region by comparing results for several gap widths including zero gap width. The calculation results underline the importance of considering inter-column gap width for the evaluation of maximum fuel temperatures and temperature gradients in fuel blocks. In addition, it is shown that temperatures of core outlet flow from gaps and channels are strongly affected by the gap width of by-pass flow in the reactor core.

2009-09-01

390

Preliminary Thermo-Hydraulic Analysis of Sulfuric Acid Loop for NHDD System  

International Nuclear Information System (INIS)

Very High Temperature gas cooled nuclear Reactor (VHTR), which was coupled with Sulfur-Iodine (SI) thermo-chemical cycle, has been selected for the Nuclear Hydrogen Development and Demonstration (NHDD) project in Korea Atomic Energy Research Institute. Among the various hydrogen production methods, Sulfur-Iodine (SI) thermo-chemical cycle is a good method as a massive hydrogen production without CO2 emission. In SI cycle, the sulfuric acid decomposition is one issue for the material corrosion on high temperature and pressure condition. For the simulation of the sulfuric acid decomposition, we designed a sulfuric acid loop with a small-scale gas loop which is simulated for the integrity and feasibility tests on a H2SO4 decomposition process. The primary objective of the loop is to validate the corrosion and the mechanical performances of a key component of the NHDD, Process Heat Exchanger (PHE). In this ...

2010-10-01

391

Potential for containment leak paths through electrical penetration assemblies under severe accident conditions  

International Nuclear Information System (INIS)

The leakage behavior of containments beyond design conditions and knowledge of failure modes is required for evaluation of mitigation strategies for severe accidents, risk studies, emergency preparedness planning, and siting. These studies are directed towards assessing the risk and consequences of severe accidents. An accident sequence analysis conducted on a Boiling Water Reactor (BWR), Mark I (MK I), indicated very high temperatures in the dry-well region, which is the location of the majority of electrical penetration assemblies. Because of the high temperatures, it was postulated in the ORNL study that the sealants would fail and all the electrical penetration assemblies would leak before structural failure would occur. Since other containments had similar electrical penetration assemblies, it was concluded that all containments would experience the same type of failure. The results of this study, ...

392

Pitting resistance of alloy 800 as a function of temperature and prefilming in high-temperature water  

Energy Technology Data Exchange (ETDEWEB)

Pitting behavior of alloy 800 was investigated as a function of temperature and prefilming in high-temperature water. The behavior was characterized in terms of pitting potential (U{sub p}) and pit density (n{sub p}). U{sub p} decreased with increasing temperature and chloride activity. Prefilming of test coupons over a period between 100 h and 5,000 h in ammoniated water at 300 C had no apparent influence on U{sub p} at room temperature, 180 C, and 300 C. However, the number of pits in prefilmed coupons was much higher than in coupons covered with an air passive layer. The effect of prefilming on pit nucleation was investigated in detail with regard to a model and test methods developed by Bianchi, et al. Density of pits in prefilmed coupons was at least 1 order of magnitude higher than in air passive coupons. Maximum pit density was measured after a prefilming period of 100 h. The effect was discussed in terms of Bianchi`s model and in terms of features of ...

1997-02-01

393

Pitting resistance of Alloy 800 as a function of temperature and prefilming in high temperature water  

Energy Technology Data Exchange (ETDEWEB)

The pitting behavior of Alloy 800 was investigated as a function of temperature and prefilming in high temperature water. The pitting behavior was characterized in terms of the pitting potential and the pit density. The pitting potential decreases with increasing temperature and chloride activity. Prefilming of test coupons over a time period between 100 and 5,000 hours in ammoniated water at 300 C has no apparent influence on the pitting potential at room temperature, 180 C and 300 C. However, the number of pits in prefilmed coupons is much higher than in coupons covered with an air passive layer. The effect of prefilming on pit nucleation was investigated in more detail with regard to a model and test methods developed by Bianchi and co-workers. Density of pits in prefilmed coupons is at least one order of magnitude higher than in air passive coupons. Maximum pit density was measured after a prefilming period of 1 00 hours. The effect is ...

1995-12-31

394

Performance of solid-lubricated ceramic ball bearings at high-temperature in a vacuum; Kotai junkatsu ceramics tamajikuuke no shinkuchu, koonka ni okeru seino  

Energy Technology Data Exchange (ETDEWEB)

Aiming to realize ball bearings operable in a vacuum and under high temperature, silicon nitride (Si3N4) ceramic ball bearings were tested. The tested ball bearings were angular contact ball bearings composed of silicon nitride with sputtered molybdenum disulfide coating using a retainer of hot-pressed self-lubricating composite material. The time variation of the frictional torque was examined for the operations under the conditions at 500{degree}C in a vacuum at a rotational speed of 600 rpm and 50N thrust load for 5{times}10{sup 7}revolutions (1400 hours) and for 1.5{times}10{sup 8}revolutions (4200 hours). Excellent tribological performance was obtained. The ball bearings are lubricated with the molybdenum disulfide film at the initial stage of the operation and with a transfer film formed from the retainer material to the balls. In a test at 650{degree}C, low and stable frictional torque was observed up to 500 hours of operation as of the ...

1996-04-05

395

Oxygen stabilization induced enhancement in superconducting characteristics of high-Tc oxides  

International Nuclear Information System (INIS)

In an attempt to enhance the electrical and mechanical properties of the high temperature superconducting oxides, high T(sub c) composites were prepared composed of the 123 compounds and AgO. The presence of extra oxygen due to the decomposition of AgO at high temperature is found to stabilize the superconducting 123 phase. Ag is found to serve as clean flux for grain growth and precipitates as pinning center. Consequently, almost two orders of magnitude enhancement in critical current densities were also observed in these composites. In addition, these composites also show much improvement in workability and shape formation. On the other hand, proper oxygen treatment of Y5Ba6Cu11Oy was found to possibly stabilize superconducting phase with T(sub c) near 250 K. I-V, ac susceptibility, and electrical resistivity measurements indicate the existence of this ultra high T(sub c) phase in this compound. ...

1991-01-01

396

Optimization of microstructure and properties of in situ formed #beta#-O-sialon-TiN composite  

International Nuclear Information System (INIS)

A powder mixture of #alpha#-Si_3N_4, Al_2O_3, and TiO_2 was hot-pressed using different sintering cycles to search for an optimum in situ formed #beta#-O-sialon-TiN composite. The impulse excitation technique (IET), high-temperature X-ray diffraction (HTXRD), and scanning electron microscopy (SEM) were used to investigate the microstructure. Below the temperature of 1300 deg. C, the high-temperature internal friction (Q "-"1) decreases with the increase of sintering temperature, whereas the density of the material increases with the increase of sintering temperature. At a sintering temperature higher than 1850 deg. C, the ceramic could not be densified and O-sialon was not formed. Also, the mechanical properties of ceramics hot-pressed using different sintering cycles were assessed. The ceramic hot-pressed at 1700 deg. C for 10 min displays a combination of high hardness and good fracture toughness, due to an optimum combination of ...

2006-07-15

397

Mullite long fibres prepared by sol-gel method using water solvent systems  

Energy Technology Data Exchange (ETDEWEB)

Mullite long fibres, which are a candidate for high temperature applications were prepared by sol-gel method from water solvent systems. They were synthesized from three different combinations of raw materials as follows: (1):Al(O{sub 1}C{sub 3}H{sub 7}){sub 3}, Al-nitrate and Si(OC{sub 2}H{sub 5}){sub 4} (TEOS), (2):Al metal, Al-chloride and TEOS, (3):Al metal, Al-nitrate and TEOS. In the methods (1) and (2), very fine SiO{sub 2} aerosol particles were also used partially replacing TEOS. The prepared solutions were condensed and examined the spinability by a hand drawing method. Dense and crack free mullite fibres were prepared from the methods (1) and (3) by firing up to 1100 C. Whereas the fibres prepared from the method (2) were less SiO{sub 2} than mullite composition and were porous by the firing due to evaporation of residual Cl ions at high temperature. (orig.) 10 refs.

1997-12-31

398

Iron Aluminide Hot Gas Filters  

Energy Technology Data Exchange (ETDEWEB)

Currently, high temperature filter systems are in the demonstration phase with the first commercial scale hot filter systems being installed on integrated gasification combined cycle (IGCC) and pressurized fluid bed combustion cycle (PBFC) systems (70 MW). They are dependent on the development of durable and economic high temperature filter systems. These filters are mostly ceramic tubes or candles. Ceramic filter durability has not been high. Failure is usually attributed to mechanical or thermal shock: they can also undergo significant changes due to service conditions. The overall objective of this project is to commercialize weldable, crack resistant filters which will provide several years service in advanced power processes. The specific objectives of this project are to develop corrosion resistant alloys and manufacturing processes to make Iron Aluminide filter media, and to use a ``short term`` ...

1996-12-31

399

Investigations on the quality of polysilicon film-gate dielectric interface in polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The effective electron mobility was measured as a function of surface field in polysilicon thin film transistors having the following three types of gate dielectrics; silicon dioxide deposited by low temperature (350degC) plasma-enhanced chemical vapor deposition (PECVD), low temperature (400degC) nitrogen-rich PECVD silicon nitride and high temperature (1050degC) thermally grown silicon dioxide. At low surface fields, the maximum true effective electron mobility was 40[+-]3 cm[sup 2] V[sup -1] s[sup -1] in all devices independent of the type of gate dielectric, indicating that the quality of the interface is the same. However, at high surface fields a stronger degradation of the mobility was observed in devices having the thermally grown silicon dioxide as gate dielectric, indicating the presence of surface roughness within the interfacial region. The polysilicon structure was studied by transmission electron microscopy in order to ensure that ...

1992-08-28

400

Investigation of #alpha#-sialon formation by high temperature X-ray diffraction  

International Nuclear Information System (INIS)

A technique for following sialon formation in situ by high temperature X-ray diffraction (HT-XRD) was developed. The composition chosen for study was an yttrium #alpha#-sialon with x=0.4. Powder compacts containing silicon nitride, aluminum nitride and yttria powders were pre-sintered at 1350 C and then studied by HT-XRD at temperatures between 1450 and 1580 C and nitrogen pressures of 0.11 MPa. The furnace was made from graphite coated with porous silicon nitride/silicon carbide. The coating prevented silicon carbide formation in the sample up to 1600 C. X-ray diffraction results show the formation of a Y_1_0Al_2Si_3O_1_8N_4 phase at 1350 C, which dissolved to form #alpha#-sialon and other phases at higher temperatures. The amounts of #alpha#-sialon formed are similar to the amounts reported by other authors. An empirical method was used for the calculation of activation energy for the silicon nitride to #alpha#-sialon transformation and ...

1993-10-04

401

Interactions between creep and corrosion in Alloy 800  

Energy Technology Data Exchange (ETDEWEB)

Metallic components within or immediately adjacent to gasifiers, such as gas distributors, thermowells, transfer lines, and cyclones, are subjected to severe of temperature, pressure, and hostile multicomponent gas environments. Metallic heat exchangers/waste-heat boilers resistant to sulfidation, corrosion. and erosion in low- and medium-Btu gas environments are essential components in large-scale gasification schemes, in both dry ash and slogging type gasifiers. Components, in general. must be resistant to corrosion, erosion, and high-temperature creep. A substantial data base is needed on the mechanical properties of materials exposed to complex gas environments to provide a more viable basis for establishing long-term reliability of components. This work examines high-temperature creep of Alloy 800, a high-chromium alloy widely used in coal conversion systems, after exposure to oxygen and oxygen/sulfur mixed-gas environments over a wide ...

1994-04-01

402

Influence of catalytic activity and reaction conditions on the product distribution in coal liquefaction; Sekitan ekikayu no seiseibutsu bunpu ni taisuru shokubai kassei oyobi hanno joken no eikyo  

Energy Technology Data Exchange (ETDEWEB)

The NiMo sulfide supported on Ketjen Black (KB) was more effective and yielded lighter oil products containing light fractions with their boiling point below 300{degree}C during the two stage liquefaction combining low temperature and high temperature hydrogenation the conventional NiMo/alumina catalyst and FeS2 catalyst. Although the NiMo/alumina yielded increased oil products during the two stage liquefaction, the lighter oil fractions did not increase and the heavier fractions increased mainly. This suggests that the hydrogenation of aromatic rings and successive cleavage of the rings are necessary for producing the light oil, which is derived from the sufficient hydrogenation of aromatic rings using catalysts. For the two stage reaction with NiMo/KB catalyst, it was considered that sufficient hydrogen was directly transferred to coal molecules at the first stage of the low temperature reaction, which promoted the solubilization of coal and ...

1996-10-28

403

Influence of C, N and Nb contents on intergranular corrosion, stress corrosion cracking and mechanical strength of alloy 600  

International Nuclear Information System (INIS)

Dependence of C, N and Nb contents on intergranular corrosion (IGC), strews corrosion cracking (SCC) and mechanical strength of alloy 600 were examined. To evaluate the corrosion resistance of heat affected zone (HAZ), post weld heat treated specimens were used. To evaluate I G C and S C C susceptibility, Ferric Sulfate-Sulfuric Acid Test and High Temperature Water Test were used. Nb is effective as a stabilizer of C. Consequently to prevent corrosion attack on H A Z in high temperature water Nb should be added more than 100 ( % C - 0.005)% and to maintain mechanical strength, Nb should be added more than 3 + 75( %C + %N)%. Modified alloy 600 satisfying above condition was manufactured commercially and its various properties including weldability were confirmed to be excellent.

1985-12-01

404

Hydraulic system for driving control rods  

International Nuclear Information System (INIS)

Purpose: To enable safety reactor shut down upon occurrence of an abnormal excess pressure in a hydraulic control unit. Constitution: The actuation pressure for a pressure switch that generates a scram signal is set lower than the release pressure set to a pressure release valve. Thus, if the pressure of nitrogen gas in a nitrogen container increases such as upon exposure of the hydraulic control unit to a high temperature, the pressure switch is actuated at first to generate the scram signal and a scram valve is opened to supply water at high pressure to control rod drives under the driving force of the nitrogen gas at high pressure to rapidly insert the control element into the reactor and shut down it. If the pressure of the nitrogen gas still increases after the scram, the pressure release valve is opened to release the nitrogen gas at high temperature to the atmosphere. Since the scram is attained ...

1980-11-07

405

High-temperature strength property evaluation of heat affected zone in boiler weldment parts of 2.25Cr-1Mo steel; 2.25Cr-1Mo ko boiler yosetsu netsu eikyobu no koon kyodo tokusei hyoka  

Energy Technology Data Exchange (ETDEWEB)

In view of the situation that aging of boiler components proceeds and some `Type IV` cracking incidents are reported recently, the development of an accurate remaining life evaluation method for boiler weldment parts is an important subject for the utilities. In this study, simulated materials with coarse and fine grain microstructures in a weldment heat affected zone were produced, and their high temperature strength properties were evaluated. The strength property of the weld joint was also discussed based on the experimental and analytical results. It was found that the creep rupture strength of the fine grain material was as low as 1/2 of the base metal and as 1/5 of the coarse grain material, and the weld joint ruptured at the fine grain region in a shorter period than the base metal as the applied stress level decreased. Many grainboundary creep cavities were also observed in the fine grain region. A creep deformation analysis by FEM ...

1998-03-15

406

High temperature friction and wear characteristics of superalloys X-750 and 188 for use in low heat rejection engines  

Energy Technology Data Exchange (ETDEWEB)

Engineering materials for use in low heat rejection engines are required to function under stringent tribological conditions. Severe wear damage and high friction between the components of the tribosystem limit the number of potential materials suitable for such application conditions. The superalloys X-750 and 188 are composed of alloying elements that not only promote a high mechanical and chemical stability but may also result in a reduced wear rate and friction coefficient at elevated temperatures. As a part of the DOE-ECUT Tribology program at Argonne, the present study was undertaken to evaluate the tribological characteristics of these alloys that will also be utilized as the substrates for ion beam deposited lubricous coatings. A wear test rig that crudely simulated the sliding conditions between a piston ring and a cylinder liner in an operating engine was utilized for friction and wear studies. The test results indicated that the wear and friction properties of these alloys ...

1988-01-01

407

High temperature fatigue damage in three austenitic alloys  

Energy Technology Data Exchange (ETDEWEB)

A series of cyclic strain controlled tests have been carried out at 600/sup 0/C on three high temperature austenitic iron-based alloys, AISI type 316 stainless steel, Alloy 800 H and Sandvik 253 MA. The tests were carried out under constant total strain control using a constant strain rate of 0.005 s/sup -1/. By considering the changes in modulus throughout the life of each specimen it was found that damage evolution could be successfully predicted as a function of plastic strain range despite the fact that each alloy had been chosen because of a different stress response at 600/sup 0/C. Although each alloy accumulated fatigue damage in a similar manner the longer lives of Sandvik 253 MA and Alloy 800 H at a given total strain range were due to a smaller plastic strain component and a reduced stage I crack propagation rate. In the 253 MA alloy, slip was predominantly planar with some cells occasionally forming at high strain ranges. Slip was ...

1988-01-01

408

Heat resistant nickel base alloy excellent in workability and high temperature strength properties  

Energy Technology Data Exchange (ETDEWEB)

A heat resistant nickel base alloy which is excellent in not only hot and cold workability but also high temperature strength properties and which also possesses satisfactory oxidation resistance. The nickel base alloy consists essentially of 0.001-0.15 percent carbon, 0.0005-0.05 percent calcium, 20.0-126.0 percent chromium, 4.7-9.4 percent cobalt, 5.0-16.0 percent molybdenum, 0.5-4.0 percent tungsten, with the total of molybdenum plus tungsten being from 9.0 to 16.5 percent, and the balance nickel and inevitable impurities. The alloy may further contain one selected from the group consisting of (1) 0.3-1.5 percent aluminum and 0.1-1.0 percent titanium, (2) 0.001-0.30 percent at least one of yttrium and rare earth elements, and (3) 0.001-1.0 percent at least one of niobium, vanadium and tantalum, whereby the aforementioned characteristics are further enhanced.

1984-10-02

409

GaP/Al/sub x/Ga/sub 1-x/P heterojunction bipolar junction transistor for high-temperature electronic applications  

Energy Technology Data Exchange (ETDEWEB)

Useful bipolar transistor action over the full temperature range from 78 to 823K has been demonstrated for mesa-isolated, liquid-phase epitaxial n/sup +/npn, GaP/Al/sub 0/ /sub 35/Ga/sub 0/ /sub 65/P/GaP/GaP structures. This represents both the highest temperature and the widest temperature range (745K) over which useful solid-state transistor action has ever been demonstrated in any III-V compound semiconductor system. These results imply that the GaP/Al/sub x/Ga/sub 1-x/P chemical system is an excellent materials candidate in which to base a technology for high-temperature electronics and the results also imply the very real possibility of functional solid-state devices and circuits at temperatures in excess of 500/sup 0/C.

1982-01-01

410

Fatigue and creep crack growth behaviour at high temperatures for weld metals of Alloy 800 and Alloy 617  

International Nuclear Information System (INIS)

High temperature fatigue crack growth (FCG) and creep crack growth (CCG) experiments have been conducted in air on weld metal, heat affected zone (HAZ) and base metal of the austenitic Alloy 800 and the nickel base Alloy 617. Tests were performed on specimens machined from pipes, in the temperature range 550-900 deg. C. The crack propagation mode was examined. At all temperatures and for both materials, FCG of base metal was found to be the highest, whereas the weld metal exhibited the lowest FCG rate. The FCG rate in the HAZ was found to lie in between of those observed for base and weld metal. The crack propagation mode remained transgranular in base metal and transdendritic in weld metal at all temperatures. CCG behaviour could be described using the energy rate integral C*. Base metal and weld metal exhibited similar CCG rate at same C*. The crack propagation mode under CCG condition was found to be intergranular in base metal and HAZ and ...

1993-08-15

411

Failure analysis of CO_2 anti-freezing heater at Daya Bay Nuclear Power Station  

International Nuclear Information System (INIS)

In this paper, an investigation was performed on a failure pressure vessel, which was as an anti-freezing heater for General Gas Storage and Distribution (SGZ) system. Evident and serious deformation was observed on the body of the vessel. A metallurgical investigation was conducted to establish the mechanism and cause of deformation of the anti-freezing heater at Daya Bay PWR station in China. The investigation, which was performed on specimens cut from the most serious area deformed of the vessel, included macroscopic examination and microscopy examination. The results of the examinations showed that some lamellar pearlite in the microstructure were already spheroidized. It was confirmed that the vessel was operated at high temperature. Stress analysis for the vessel was conducted. And it was confirmed that, in ideal conditions, the vessel would be deformed at around 420 C. The overall results of the investigation showed that the failure of ...

2002-09-23

412

Fabrication and characterization of Cu/YSZ cermet high temperature electrolysis cathode material prepared by high-energy ball-milling method  

Energy Technology Data Exchange (ETDEWEB)

Cu/YSZ cermet (40 and 60 vol.% Cu powder with balance YSZ) is a more economical cathode material than the conventional Ni/YSZ cermet for high temperature electrolysis (HTE) of water vapor and it was successfully fabricated by high-energy ball-milling of Cu and YSZ powders, pressing into pellets (o 13 mm x 2 mm) and subsequent sintering process at 700 deg. C under flowing 5%-H{sub 2}/Ar gas. The Cu/YSZ composite material thus fabricated was characterized using various analytical tools such as XRD, SEM, and laser diffraction and scattering method. Electrical conductivity of sintered Cu/YSZ cermet pellets thus fabricated was measured by using 4-probe technique for comparison with that of conventional Ni/YSZ cermets. The effect of composite composition on the electrical conductivity was investigated and a marked increase in electrical conductivity for copper contents greater than 40 vol.% in the composite was explained by percolation threshold. ...

2009-01-07

413

Experimental and analytical studies on turbulent heat transfer performance of a fuel rod with spacer ribs for high temperature gas-cooled reactors  

International Nuclear Information System (INIS)

Turbulent heat transfer performance of a fuel rod with three-dimensional trapezoidal spacer ribs for high temperature gas-cooled reactors was studied for various Reynolds numbers using an annular channel at the same coolant condition as the reactor operation, maximum outlet temperature of 1000 C and pressure of 4 MPa, and analytically by a numerical simulation using the k-#epsilon# turbulence model. The turbulent heat transfer coefficients of the fuel rod were 18-80% higher than those of a concentric smooth annulus at a region of Reynolds number exceeding 2000. On the other hand, the predicted average Nusselt number of the fuel rod agreed well with the empirical correlation obtained from the experimental data within a relative error of 10% with Reynolds number of more than 5000. It was verified that the numerical analysis results had sufficient accuracy. Furthermore, the numerical prediction could clarify quantitatively the effects of the heat ...

414

Effect of hydrostatic pressure on photoluminescence spectra from structures with Si nanocrystals fabricated in SiO_2 matrix  

International Nuclear Information System (INIS)

The effect of hydrostatic pressure applied at high temperature on photoluminescence of Si-implanted SiO_2 films was studied. A 'blue'-shift of PL spectrum from the SiO_2 films implanted with Si"+ ions to total dose of 1.2x10"1"7 cm"-"2 with increase in hydrostatic pressure was observed. For the films implanted with Si"+ions to a total dose of 4.8x10"1"6 cm"-"2 high temperature annealing under high hydrostatic pressure (12 kbar) causes a 'red'-shift of photoluminescence spectrum. The 'red' photoluminescence bands are attributed to Si nanocrystals while the 'blue' ones are related to Si nanocrystals of reduced size or chains of silicon atoms or Si-Si defects. A decrease in size of Si nanocluster occurs in result of the pressure-induced decrease in the diffusion of silicon atoms. (author)

2001-09-23

415

Development of the fabrication process for SiC reinforced gamma-TiAl intermetallic composites; SiC sen`i kyoka TiAl kinzokukan kagobutsu fukugo zairyo no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

In case of airplane engine, technical development like increase of temperature at the turbine entrance or high speed rotation with a purpose of thrust up, and reduction of structural part single substance mass or reduction of number of parts in order to achieve lightness and so forth, has been promoted in order to improve the performance that is evaluated by thrust weight ratio (thrust/weight). Accordingly, research and development of high heat resistance, high strength, lightness and so forth of each material of the parts are in demand. As a representative material corresponding to such demand, L10 type {nu}-TiAl intermetallic compound which is light and has improved high temperature strength properties is paid attention and its development is promotes. The authors were successful for the first time in the world to manufacture composite material with CVD type SiC fiber that was difficult so far by using TiAl-Cr alloy having super plasticity at ...

1998-04-20

416

Development of a high-performance, coal-fired power generating system with a pyrolysis gas and char-fired high-temperature furnace  

International Nuclear Information System (INIS)

A high-performance power system (HIPPS) is being developed. This system is a coal-fired, combined-cycle plant that will have an efficiency of at least 47 percent, based on the higher heating value of the fuel. The original emissions goal of the project was for NOx and SOx to each be below 0.15 lb/MMBtu. In the Phase 2 RFP this emissions goal was reduced to 0.06 lb/MMBtu. The ultimate goal of HIPPS is to have an all-coal-fueled system, but initial versions of the system are allowed up to 35 percent heat input from natural gas. Foster Wheeler Development Corporation is currently leading a team effort with AlliedSignal, Bechtel, Foster Wheeler Energy Corporation, Research-Cottrell, TRW and Westinghouse. Previous work on the project was also done by General Electric. The HIPPS plant will use a high-Temperature Advanced Furnace (HITAF) to achieve combined-cycle operation with coal as the primary fuel. The HITAF is an atmospheric-pressure, pulverized-fuel-fired ...

1995-07-12

417

Deposit formation tendency of lubricants at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

A thin film microoxidation test utilizing the concept of the Lubricant Stability Map has been used to study the effect of temperature on deposit formation by lubricants on upper piston locations of low heat rejection engines. The stability maps were established for two formulated lubricants in this study. These two lubricants were also evaluated in a series of engine tests with various piston temperatures. The deposition phenomena observed in the engine tests have been adequately simulated and described by the stability maps. It is concluded that lubricants at upper piston locations are under a thin film condition similar to that achieved by the thin film microoxidation test. The deposit formation trend is determined by the volatility, thermal stability, and oxidative stability of the base stock. Additives have little effect on deposit formation at very high temperatures. A combined consideration of all competing reaction pathways at a specific ...

1995-05-01

418

Corrosion test and service result of materials used for fuel injection nozzles in marine diesel engines  

Energy Technology Data Exchange (ETDEWEB)

Corrosion test, as a material selection test method of nozzle to be used in the marine diesel engine, was adopted and discussed. Due to the heightening in output power and lengthening in stroke of the marine diesel engine, the fuel injection nozzle became so severe in working condition that the nozzle tip became in lift 1/6 to 1/18 time as long as that of short stroke type in past. Then upon investigating cause of damage, the damage was confirmed to be mainly caused by the high temperature sulfidization corrosion. Then by preparing 20 kinds of candidate test piece and making sulfidization corrosion test in accordance with the high temperature corrosion test procedure, corrosiveness was evaluated through change in weight between before and after testing. As a result of testing, three kinds of test piece, inclusive of high Ni-Cr-Al alloy's, showed a high anti-corrosiveness. Those kinds of test ...

1989-06-15

419

Corrosion control. 2. ed.  

International Nuclear Information System (INIS)

The purpose of this text is to train engineers and technologists not just to understand corrosion but to control it. Materials selection, coatings, chemical inhibitors, cathodic and anodic protection, and equipment design are covered in separate chapters. High-temperature oxidation is discussed in the final two chapters ne on oxidation theory and one on controlling oxidation by alloying and with coatings. This book treats corrosion and high-temperature oxidation separately. Corrosion is divided into three groups: (1) chemical dissolution including uniform attack, (2) electrochemical corrosion from either metallurgical or environmental cells, and (3) stress-assisted corrosion. Corrosion is logically grouped according to mechanisms rather than arbitrarily separated into different types of corrosion as if they were unrelated. For those university students and industry personnel who approach corrosion theory very hesitantly, this text will present ...

420

Corrosion control. 2. ed  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this text is to train engineers and technologists not just to understand corrosion but to control it. Materials selection, coatings, chemical inhibitors, cathodic and anodic protection, and equipment design are covered in separate chapters. High-temperature oxidation is discussed in the final two chapters ne on oxidation theory and one on controlling oxidation by alloying and with coatings. This book treats corrosion and high-temperature oxidation separately. Corrosion is divided into three groups: (1) chemical dissolution including uniform attack, (2) electrochemical corrosion from either metallurgical or environmental cells, and (3) stress-assisted corrosion. Corrosion is logically grouped according to mechanisms rather than arbitrarily separated into different types of corrosion as if they were unrelated. For those university students and industry personnel who approach corrosion theory very hesitantly, this text will present ...

2001-07-01

421

Bypass Flow and Hot Spot Analysis for PMR200 Block-Core Design with Core Restraint Mechanism  

Energy Technology Data Exchange (ETDEWEB)

The accurate prediction of local hot spot during normal operation is important to ensure core thermal margin in a very high temperature gas-cooled reactor because of production of its high temperature output. The active cooling of the reactor core determining local hot spot is strongly affected by core bypass flows through the inter-column gaps between graphite blocks and the cross gaps between two stacked fuel blocks. The bypass gap sizes vary during core life cycle by the thermal expansion at the elevated temperature and the shrinkage/swelling by fast neutron irradiation. This study is to investigate the impacts of the variation of bypass gaps during core life cycle as well as core restraint mechanism on the amount of bypass flow and thus maximum fuel temperature. The core thermo fluid analysis is performed using the GAMMA+ code for the PMR200 block-core design. For the analysis not only are some ...

2009-10-15

422

Bypass Flow and Hot Spot Analysis for PMR200 Block-Core Design with Core Restraint Mechanism  

International Nuclear Information System (INIS)

The accurate prediction of local hot spot during normal operation is important to ensure core thermal margin in a very high temperature gas-cooled reactor because of production of its high temperature output. The active cooling of the reactor core determining local hot spot is strongly affected by core bypass flows through the inter-column gaps between graphite blocks and the cross gaps between two stacked fuel blocks. The bypass gap sizes vary during core life cycle by the thermal expansion at the elevated temperature and the shrinkage/swelling by fast neutron irradiation. This study is to investigate the impacts of the variation of bypass gaps during core life cycle as well as core restraint mechanism on the amount of bypass flow and thus maximum fuel temperature. The core thermo fluid analysis is performed using the GAMMA+ code for the PMR200 block-core design. For the analysis not only are some ...

2009-10-01

423

Atomistic modeling of the effects of dose and implant temperature on dopant diffusion and amorphization in Si  

International Nuclear Information System (INIS)

We discuss atomistic simulations of ion implantation and annealing of Si over a wide range of ion dose and substrate temperatures. The DADOS Monte Carlo model has been extended to include the formation of amorphous regions, and this allows simulations of dopant diffusion at high doses. As the dose of ions increases, the amorphous regions formed by cascades eventually overlap, and a continuous amorphous layer is formed. In that case, most of the excess interstitials generated by the implantation are swept to the surface as the amorphous layer regrows, and do not diffuse in the crystalline region. This process reduces the amount of transient enhanced diffusion (TED) during annealing. This model also reproduces the dynamic annealing during high temperature implants. In this case, the local amorphous regions regrow as the implant proceeds, without the formation of a continuous amorphous layer. For sufficiently high ...

2001-06-01

424

Application of automatic inspection system to nondestructive test of heat transfer tubes of primary pressurized water cooler in the high temperature engineering test reactor. Joint research  

International Nuclear Information System (INIS)

Heat transfer tubes of a primary pressurized water cooled (PPWC) in the high temperature engineering test reactor (HTTR) form the reactor pressure boundary of the primary coolant, therefore are important from the viewpoint of safety. To establish inspection techniques for the heat transfer tubes of the PPWC, an automatic inspection system was developed. The system employs a bobbin coil probe, a rotating probe for eddy current testing (ECT) and a rotating probe for ultrasonic testing (UT). Nondestructive test of a half of the heat transfer tubes of the PPWC was carried out by the automatic inspection system during reactor shutdown period of the HTTR (about 55% in the maximum reactor power in this paper). The nondestructive test results showed that the maximum signal-to-noise ratio was 1.8 in ECT. Pattern and phase of Lissajous wave, which were obtained for the heat transfer tube of the PPWC, were different from those obtained for the ...

425

An Assessment of Through Thickness Mechanical Properties in Forged Thick Section Mod. 9Cr-1Mo Steel  

International Nuclear Information System (INIS)

Ferritic/martensitic steel, modified 9Cr-1Mo steels have been used most extensively in the power generation industry throughout the world due to having superior high temperature properties such as high strength, creep resistance, and good microstructure stability. These steels are also the primary candidate for the RPVs(Reactor Pressure Vessels) of High Temperature Gas-Cooled Reactors. Currently, many studies has been conducted in laboratory-scale for mod. 9Cr-1Mo steels. However, there is a lack of the study on forged thick- section for RPVs. The differences in characteristics including the through thickness microstructure and mechanical properties between internal and external locations may occur during cooling after austenitization, because the thickness of RPVs is over about 200mm. Therefore, in order to use ferritic/martensitic steel as RPVs, a detailed assessment of the through thickness ...

2010-10-01

426

Alloy 800: New stress rupture and creep data for pressurized components in high temperature reactors  

Energy Technology Data Exchange (ETDEWEB)

In an HTR plant high temperature components of Alloy 800 materials are subjected to temperatures from about 550 to 850degC in the long term; higher temperatures may occur in the short term. Thus the creep and stress-rupture parameters govern the design of these components. Since in recent years the scope of experimental data available for Alloy 800 materials has considerably increased, a new evaluation of the creep and creep-rupture properties was performed using a data bank computer. The relationships between the characteristics of the creep and creep-rupture behaviour and the metallurgical parameters were investigated by multilinear regression analyses. On the basis of the results of these analyses and after discussion in material expert committees new material specifications were determined for different types of Alloy 800. They were included into the draft standards DIN 17459 and DIN 17460 under the material standard nos. 1.4958, 1.4958 Rk ...

1990-05-01

427

Alloy 800: New stress rupture and creep data for pressurized components in high temperature reactors  

International Nuclear Information System (INIS)

In an HTR plant high temperature components of Alloy 800 materials are subjected to temperatures from about 550 to 850degC in the long term; higher temperatures may occur in the short term. Thus the creep and stress-rupture parameters govern the design of these components. Since in recent years the scope of experimental data available for Alloy 800 materials has considerably increased, a new evaluation of the creep and creep-rupture properties was performed using a data bank computer. The relationships between the characteristics of the creep and creep-rupture behaviour and the metallurgical parameters were investigated by multilinear regression analyses. On the basis of the results of these analyses and after discussion in material expert committees new material specifications were determined for different types of Alloy 800. They were included into the draft standards DIN 17459 and DIN 17460 under the material standard nos. 1.4958, 1.4958 Rk ...

428

Alloy 800: Low cycle fatigue curves as the basis for design against fatigue failure of HTR components  

Energy Technology Data Exchange (ETDEWEB)

For a reliable design against fatigue failure of high-temperature components of different types of the heat resistant material Alloy 800, verified parameters of the low-cycle fatigue (LCF) behaviour are required. These parameters were obtained by a scatterband evaluation of the results of low-cycle fatigue tests, using a computerized data bank which includes all available actual data sets. The results of the evaluation are presented as mean fatigue curves with the upper and lower boundary limits of the scatterbands. For the type Alloy 800 in the recrystallization annealed condition, the results cover a temperature range from 20 to 750deg C; for the solution annealed types they cover a temperature range from 20 to 950deg C. Specimens tested in HTR helium at high temperatures had longer lives than specimens tested in air. This effect was represented quantitatively by the ratio of the total strain ranges from tests in HTR ...

1990-05-01

429

Adsorption of mercury vapor on particles  

Energy Technology Data Exchange (ETDEWEB)

The adsorption of mercury vapor on particles was studied by using soot particles generated by incineration of sewage sludge (EP-ash) and activated carbon particles. Through the experiments, it was found that, at 298 K, the EP-ash has a fairly high adsorption capacity for mercury vapor in the order of 10/sup -6/g/g, which is between that of the ordinary soils and that of activated carbon particles. Furthermore, it was found that physical adsorption of mercury vapor on the studied particles at high temperature is described by Dubinin's equation. On the basis of the equation, it was shown that EP-ash physically adsorbs very little mercury at high temperature, and therefore, most mercury in the EP-ash is chemically adsorbed or contained in a form of mercury compounds. Nevertheless, the total amount of mercury contained in the particles is very little compared to the total mercury in the exhaust ...

1986-07-01

430

A-15 compounds and their amorphous counterparts  

International Nuclear Information System (INIS)

The A-15 compounds are known to favor the occurrence of high temperature superconductivity (transition temperature T/sub c/ > 15K). The origin of superconductivity in these metals is a subject of much controversy and importance. A useful approach to this problem is to study comparatively the superconducting and normal-state properties of the A-15 superconductors and their amorphous counterparts. Efforts along these lines have yielded some insight into the mechanisms responsible for high temperature superconductivity. It is interesting to note that most high-T/sub c/ A-15 compounds contain one glass-forming element such as Ge, Si or Al and are thus conducive to the formation of a non-crystalline phase. The amorphous (or higher disordered) state of the A-15 compounds can be achieved, for example, by one of the following techniques: (1) sputtering or co-evaporation onto substrates held at relatively low ...

431

A novel high temperature stable lithium salt (Li{sub 2}B{sub 12}F{sub 12}) for lithium ion batteries  

Energy Technology Data Exchange (ETDEWEB)

Basic properties and battery performances of the novel high temperature stable lithium salt (Li{sub 2}B{sub 12}F{sub 12}, Dilithium Dodecafluorododecaborate; Li{sub 2}DFB) were studied using a Mn-based cathode and anode composed of a hard carbon and graphite mixture. The effect of co-solvents (mainly linear carbonate in electrolyte formulation of PC/EC/co-solvent (5/30/65 vol% mixture)) on conductivity, viscosity, charge-discharge capacities, rate performance, temperature performance, cycle life and storage life at 60 C was investigated. Conductivity of Li{sub 2}DFB electrolyte increased with reducing its viscosity by changing co-solvent and increasing the volume of the higher dielectric solvent. Li{sub 2}DFB electrolytes showed comparable discharge capacity and columbic efficiency against LiPF{sub 6} electrolyte. Li{sub 2}DFB electrolytes improved the storage life and cycle life of a Mn-based cell at 60 C. (author)

2009-09-05

432

3-D CFD MODEL OF A MULTI-CELL HIGH TEMPERATURE ELECTROLYSIS STACK  

Energy Technology Data Exchange (ETDEWEB)

A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis stack performance and steam electrolysis in the Idaho National Laboratory (INL) Integrated Lab Scale (ILS) experiment. The model is made of 60 planar cells stacked on top of each other operated as Solid Oxide Electrolysis Cells (SOEC). Details of the model geometry are specific to a stack that was fabricated by Ceramatec, Inc. and tested at INL. Inlet and outlet plenum flow and distribution are considered. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of ...

2009-05-01

433

Understanding the operation and use of high temperature electrochemical corrosion rate probes  

Energy Technology Data Exchange (ETDEWEB)

Electrochemical corrosion rate probes were constructed and tested along with mass loss coupons in a N2/O2/CO2 plus water vapor environment. Temperatures ranged from 450 to 600 C. Corrosion rates for ash-covered mild steel, 304L SS, and 316L SS probes using electrochemical techniques were a function of time, temperature, and process environment. Correlation between electrochemical and mass loss corrosion rates was good.

2004-01-01

434

Tube bundle for a heat exchanger  

International Nuclear Information System (INIS)

The tube bundle arrangement is suitable as reheating section of a steam generator in combination with a gas-cooled reactor. For any high-temperature section with a straightline type tube bundle, there is one inlet and one outlet collecting main; these two are arranged one opposite to the other and diametrically to the tube bundle. There are a number of lines from the inlet collecting main to the outlet collecting main; these lines are arranged axially one on top of the other and run around the tube bundle helically several times. (GL) 891 GL/GL 892 MB.

435

Three-dimensional numerical simulation of temperature field and helium flow field in ITER China TBM  

International Nuclear Information System (INIS)

Three dimensional temperature field and helium flow field of TBM are simulated using the general purpose computational fluid dynamics (CFD) code FLUENT. The temperature distribution of Be Armor, Be Pebble Bed, Li_4SiO_4 Pebble Bed, Structure Material of TBM, and helium flow field in the cooling pipe are presented. The research indicates that the work temperature of each material is under the material temperature allowed except some places where high temperature should be excluded in the design. The results will provide references for further optimized thermal hydraulic design of ITER China TBM. (authors)

2006-02-01

436

Thermophotovoltaics. Basic principles and critical aspects of system design  

Energy Technology Data Exchange (ETDEWEB)

Thermophotovoltaics is the science and technology associated with the direct generation of electricity from high temperature heat. Potential applications include combined heat and power, portable and auxiliary power, radioisotope space power, industrial waste heat recovery and concentrated solar power. This book aims at serving as an introduction to the underlying theory, overview of present day components and system arrangements, and update of the latest developments in the field. The emphasis is placed on the understanding of the critical aspects of efficient thermophotovoltaic system design. The aim is to assist researchers in the field. (orig.)

2011-07-01

437

Thermonuclear reactivity of D-T fusion plasma with spin-polarized fuel  

Energy Technology Data Exchange (ETDEWEB)

The thermonuclear reactivity of deuterium(D) - tritium(T) fusion plasma with spin-polarized fuel has been studied. Two mechanisms of depolarization, collisions and waves, in the high temperature fusion plasma have been considered. The binary collisions have been found not to change the nuclear spin states. The waves with a frequency of a few GHz, however, changes the spin states appreciably, when {delta}B/B{sub 0} (the ratio of the amplitude of the fluctuating magnetic field to the external field) becomes larger than 10{sup -5}. (author)

1999-04-01

438

Thermally isolated pipeline  

Energy Technology Data Exchange (ETDEWEB)

The pipelines is provided for gases, particluarly helium, at temperature of about 1000/sup 0/C (pressure about 40 bar) and is used as the connection be tween a gas cooled high temperature reactor and a heat load. The pipe consists of a temperature-resistant inner tube, which is composed of several pipe sections, which are supported on ball bearings, and a gas tight pressurised outer tube. There are supports and insulation between the two tubes. The sub-claims concern fixing of and bearings for the pipe sections. The description is very detailed and supplemented by drawings.

1980-08-28

439

The effect of flow velocity on pitting corrosion and stress corrosion cracking of reactor materials  

International Nuclear Information System (INIS)

This paper describes two research programs which are currently underway in the author's laboratory to investigate the effect of fluid flow on the degradation of power plant materials in high temperature/high pressure aqueous environments. These programs include the design and operation of a controlled hydrodynamic corrosion testing apparatus that can be used to study the general and localized corrosion characteristics of alloys in simulated nuclear reactor environments, and a study of the effect of flow velocity on the stress corrosion cracking of ASTM A508 C1.2 steel and Type 304SS in simulated BWR heat transport fluids.

440

The Formation of Multipoles during the High-Temperature Creep of Austenitic Stainless Steels  

DEFF Research Database (Denmark)

It is shown that multipole dislocation configurations can arise during power-law creep of certain austenitic stainless steels. These multipoles have been analysed in some detail for two particular steels (Alloy 800 and a modified AISI 316L) and it is suggested that they arise either during instantaneous loading or during the primary creep stage. Trace analysis has shown that the multipoles are confined to {1 1 1} planes during primary creep but are not necessarily confined to these planes during steady-state creep unless they are pinned by interstitials.

1981-01-01

441

Temperature measurements via narrow line laser absorption of carbon dioxide  

Energy Technology Data Exchange (ETDEWEB)

Theoretical development for temperature measurements via narrow line, infrared absorption of carbon dioxide (CO{sub 2}) is presented. The proposed technique is based on rapid-scanning of two adjacent absorption line shapes. Spectroscopic considerations for sensitivity to temperature measurements are discussed. Several line pairs are evaluated, and the R(58) and R(60) transitions of the (00{sup 0}1){l_arrow}(00{sup 0}0) band are suggested for use in high temperature measurements for combustion systems.

1996-12-31

442

Tank of sodium cooled fast reactor  

International Nuclear Information System (INIS)

Object: To provide a tank, which can safely and reliably accommodate high temperature sodium containing radioactive substance in case of occurrence of an accident in a sodium system and thus prevent spread of contamination. Structure: A sodium drain duct inserted into a tank from above the tank is provided at the position of its lower end with a buffer means for preventing direct flow-down of sodium to a bottom plate. A means for preventing the discharge of radioactive substance to the cover gas is provided above the lower end of the sodium drain tube so as to surround the sodium drain tube. (Kamimura, M.).

443

Synthesis of CdSe nanoparticles and their effect on the antioxidant activity of Spirulina platensis and Porphyridium cruentum cells  

International Nuclear Information System (INIS)

Single-crystalline cadmium selenide nanoparticles were obtained using high-temperature solution phase synthesis (HTSPS) synthesis. X-Ray powder diffraction and transmission electron microscopy were used to confirm the crystallinity and morphology of the resulting nanoparticles. To study the action of CdSe on antioxidant activity, we selected two biotechnological important strains of microalgae: cyanobacteria Spirulina platensis and red microalgae Porphyridium cruentum. In the case of Porphyridium cruentum, the obtained results demonstrated an increase in the productivity. For Spirulina platensis, the presence of the compound in the cultivating medium decreased the productivity of cyanobacteria.

2011-07-07

444

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.''.

445

Strain induced hardening in Ti-3Al-4V at 910 deg. C  

International Nuclear Information System (INIS)

High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-4V has been investigated at 910 deg. C. by using the method of cross head speed cycling. On the basis of flow stress, strain rate and strain rate sensitivity data, the alloy was found to exhibit strain hardening at this temperature which resulted in degradation in superplastic properties of the alloy. A high beta-phase volume fraction and grain-growth in both alpha and beta phases were considered responsible for the observed hardening effect. (author)

446

Sophisticated applications of radiation heat transfer  

International Nuclear Information System (INIS)

A large amount of energy has been consumed so far in so called matured industries such as iron and steel, oil refinery, petrochemical, ceramic, paper and pulp manufacturing and so forth. A successive stimulation on the preceding industries has to be enhanced from a technological viewpoint in order to maintain a further development based on novel and innovative technologies. In this regard, energy technology has become and will be increasingly important in a high temperature system so that the basic concept for heat transfer augmentation methods by thermal radiation is reviewed briefly in accord with the recent developments together with theoretical background and the prominent features. The heat transfer augmentation related to thermal radiation is summarized.

1987-01-01

447

Simple model for characterizing the electrical resistivity in A-15 superconductors  

Science.gov (United States)

A discussion of some of the difficulties with previous analyses of the resistivity of A-15 compounds is given. Precise high-temperature data on ..cap alpha..-particle- and electron-damaged Nb/sub 3/Ge and Nb/sub 3/Sn samples with different defect concentrations are presented here and analyzed in a simple way with use of a phenomenological model based on the idea that the ideal resistivity must approach some limiting value in the regime where the mean free path becomes comparable to the interatomic spacing.

1977-04-04

448

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H/sub 2/O approx. = 1) at a reduced pressure (less than or equal to4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

1988-03-01

449

Simple method for high-temperature separation of thallium isotopes from a bulk lead target  

International Nuclear Information System (INIS)

A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H_2O #approx =# 1) at a reduced pressure (#<=#4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.

450

RBS Characterization of Yttrium Iron Garnet Thin Films  

International Nuclear Information System (INIS)

Magnetic materials such as yttrium iron garnet (YIG) are of great importance for its magneto-optic properties and for their potential applications in the domain of optical telecommunications. The deposition of thin films of YIG, on quartz or GGG (gadolinium gallium garnet) substrate, was performed using radio frequency non reactive magnetron sputtering, followed by high temperature annealing which is needed to enhance the crystallinity of the layers. Rutherford backscattering spectrometry RBS was used to determine the thickness and stoichiometry of the performed layers in order to investigate correlations between growth conditions and the quality of the final material. RBS measurements showed the influence of the deposition time and the temperature substrate on the film growth and its stoichiometry. (author)

2008-12-13

451

Production of a potassium silicate fertilizer from fly ash and red mud  

Energy Technology Data Exchange (ETDEWEB)

A study is reported of the use of three types of fly ash as a raw material in the production of a potassium silicate fertilizer. The results of high-temperature X-ray diffraction, calcination tests and chemical analyses indicate that a potassium silicate fertilizer conforming with fertilizer specifications can be produced by appropriate regulation of calcining temperature and the amounts of Fe/sub 2/0/sub 3/, Al/sub 2/O/sub 3/, MgO and CaO added. The results of tests of fertilizers incorporating red mud are also reported.

1985-01-01

452

Processing and properties of novel high strength {gamma}-TiAl  

Energy Technology Data Exchange (ETDEWEB)

Extrusion and subsequent heat treatment of the alloys investigated can lead to reasonable room temperature ductilities and very high strengths being developed compared to the cast + HlPed material. In Ti-45Al-10Nb reasonably room temperature fracture toughness was developed which did not depend on extrusion temperature. For the alloy Ti-48Al-2Cr-0.2C a previously developed solution and ageing heat treatment did not increase the high temperature strength properties when compared to the 'annealed' condition. (orig.)

2000-07-01

453

Photoluminescence and cathodoluminescence properties of Tb3+ activated Sr3AlO4F emitting-color tunable phosphor  

British Library Electronic Table of Contents (United Kingdom)

Tb3+-activated Sr3AlO4F phosphors were synthesized by a high-temperature solid-state reaction method. The investigation of photoluminescence and cathodoluminescence indicates that these phosphors can be effectively excited by ultraviolet light and low-voltage electron beam. The phosphors exhibit a tunable-green emission. The luminescence behaviors are explained by the site occupancy of Tb3+ ions in the host crystal and the cross-relaxation of 5D3 to 5D4 state.

2011-01-01

454

Photoluminescence and cathodoluminescence properties of Tb3+ activated Sr3AlO4F emitting-color tunable phosphor  

Science.gov (United States)

Tb3+-activated Sr3AlO4F phosphors were synthesized by a high-temperature solid-state reaction method. The investigation of photoluminescence and cathodoluminescence indicates that these phosphors can be effectively excited by ultraviolet light and low-voltage electron beam. The phosphors exhibit a tunable-green emission. The luminescence behaviors are explained by the site occupancy of Tb3+ ions in the host crystal and the cross-relaxation of 5D3 to 5D4 state.

2011-03-01

455

Photochemical reactions of surface ozone  

International Nuclear Information System (INIS)

Efforts has been made to specify surface ozone production in photochemical reaction due to the high concentration of NO_x and photon rays. The secondary reactions has been considered via optical measurements using actinometry and pyranometry which was followed for photochemical reactions at high temperature and because of air pollutants due to the traffic load and because of the inversion in certain days. The concentration of surface ozone which was measured in Tehran city center was in the range of 24- 45 ppb in 1991-1992 and a higher concentration of 45-65 ppb was measured in 1999-2000. This high surface ozone concentration could cause a severe damage to biota, fauna and human health.

2003-01-01

456

Performance of rubber heat-stable and radiation-stable seals in helium coolant lines  

International Nuclear Information System (INIS)

The integrity of helium circulation loop flanged joints has been attracting recent attention as a design problem, in the development of high-temperature facilities incorporating helium loops (e.g., the VRG-50 pilot nuclear facility). Elevated temperatures and pressures, and the radiation environment, impose additional requirements on sealant materials. This applies first and foremost to rubber seals, which have found widespread favor on account of its excellent elasticity, its ability to spontaneously conform to possible changes in the clearance in the seal assembly, and the low compressive stresses developed in the flange joint assembly.

457

Neutron irradiation effects in austenitic alloys  

International Nuclear Information System (INIS)

The post (neutron) -irradiation high-temperature tensile and creep-rupture properties, deformation and fracture characteristics of austenitic alloys, particularly solution annealed Type 316 steel, are surveyed and correlated with the damage structures developed as a function of irradiation temperature (and dose). The mechanisms proposed to explain the irradiation-induced changes in properties and behaviour are summarised. The factors responsible for the observed differences in the post-irradiation and 'in-reactor' creep-rupture properties and behaviour of an austenitic steel are discussed in terms of the helium gas and stress driven growth of small intergranular bubbles and the atom plating associated with their growth and coalescence. (author).

1980-03-01

458

Nb_3Al: paradigm for high T/sub c/ superconductors  

International Nuclear Information System (INIS)

The A-15 compounds with the highest critical temperatures and critical fields are stable only at high temperatures and sometimes are not stable at any temperature. Fabrication of such materials thus necessarily involves the creation and manipulation of metastable phases. It follows that the bronze matrix technique now under development for Nb_3Sn- and V_3Ga-based composite superconductors is not suitable for high-T/sub c/ materials of the Nb_3 (Al, Ge, Ga, Si) family. Alternative technologies will be necessary for such materials. Efforts to develop suitable alternatives, using Nb_3Al, are described.

459

Nanocrystalline and policrystalline phases present in the protective metalloceramic coatings  

International Nuclear Information System (INIS)

New data about the structure of high-temperature resistant metalloceramic plasma sprayed coatings in micro and nano areas are presented. Application of the new instrumental methods: transmission electron microscopy combined with selected area electron diffraction mode is possible to obtain these data. The first layer in Ni based metallic bond coat shows nanocrystalline structure. External ceramic layer based on stabilised ZrO_2 is polycrystalline and contains both cubic and tetragonal crystalline phases. Local inhomogeneities in coatings phase composition are determined. (author)

2001-09-23

460

Midwest Superconductivity Consortium: 1994 Progress report  

Energy Technology Data Exchange (ETDEWEB)

The mission of the Midwest Superconductivity Consortium, MISCON, is to advance the science and understanding of high {Tc} superconductivity. During the past year, 27 projects produced over 123 talks and 139 publications. Group activities and interactions involved 2 MISCON group meetings (held in August and January); with the second MISCON Workshop held in August; 13 external speakers; 79 collaborations (with universities, industry, Federal laboratories, and foreign research centers); and 48 exchanges of samples and/or measurements. Research achievements this past year focused on understanding the effects of processing phenomena on structure-property interrelationships and the fundamental nature of transport properties in high-temperature superconductors.

1995-01-01

461

Metal- matrix composite processing technologies for aircraft engine applications  

Science.gov (United States)

Titanium metal-matrix composites (MMC) are prime candidate materials for aerospace applications be-cause of their excellent high-temperature longitudinal strength and stiffness and low density compared with nickel- and steel-base materials. This article examines the steps GE Aircraft Engines (GEAE) has taken to develop an induction plasma deposition (IPD) processing method for the fabrication of Ti6242/SiC MMC material. Information regarding process methodology, microstructures, and mechani-cal properties of consolidated MMC structures will be presented. The work presented was funded under the GE-Aircraft Engine IR & D program.

1993-06-01

462

Mechanical properties of titanium-niobium carbon nitride  

Energy Technology Data Exchange (ETDEWEB)

A study was made of the variation in strength characteristics of group IV transition metal carbon nitrides alloyed with carbides or group V metal nitrides. A complex solid solution of titanium-niobium carbonitride was preliminarily synthesized to a homogeneous equilibrium state and then crushed. The calculated quantity of binder metal was added as elemental powders, the mixture was vibration ball milled in ethanol and the plasticized charge was used to press experimental specimens for mechanical testing. The studies showed that the high-temperature strength properties of the new cermet are superior to standard type KNT. The material is thus promising for use in the manufacture of tools. 8 references, 3 figures.

1984-07-01

463

Measurement of Turbulence Decorrelation during Transport Barrier Evolution in a High Temperature Fusion Plasma  

Energy Technology Data Exchange (ETDEWEB)

A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengths observed earlier in the discharge, while the density fluctuation level remain similar to the level before transport barrier formation.

2005-03-29

464

Macro and micro observations on mortar alternation mechanism under the various solution conditions  

Energy Technology Data Exchange (ETDEWEB)

Accelerated aging tests have been conducted to evaluate the long-term durability of cementitious material against aggressive ions. In tests, cementitious specimens were immersed in the solutions containing concentrated aggressive ions at high temperature and it promoted diffusion of the ions in the specimen. This method would be suitable for the evaluation on the aging as the alteration of the specimen would be expected to resemble the natural behavior. This paper presents a classification of alteration mechanism in the immersion tests using MgCl{sub 2} and Na{sub 2}SO{sub 4} solution. This classification was done by relating the changes of compressive strength to microscopic and mineralogical changes.

1995-12-31

465

Local-density-functional approximation to the energy band structure of TmS using the self-consistent relativistic linearized-augmented-plane-wave method  

International Nuclear Information System (INIS)

The self-consistent relativistic linearized-augmented-plane-wave method is applied to local-density calculation of electronic structure of TmS. It is found that thulium monosulphide is a compound with a trivalent state of thulium. The influence of spin-orbital interaction is shown for different symmetry states of electrons. Calculated densities of states are used for the estimation of the electron-phonon coupling constant. And in conclusion it is shown that TmS is a high temperature Kondo-like system. (author).

466

Line-focus solar central power system, Phase I. Final report, 29 September 1978 to 30 April 1980. Volume II. Text  

Energy Technology Data Exchange (ETDEWEB)

The conceptual design, parametric analysis, cost and performance analysis, and a commercial assessment of a 100-MWe high-temperature line-focus central power system are presented. Parametric analyses and conceptual design of the heliostat subsystem, receiver subsystem, heat transport subsystem, energy storage subsystem, electrical power generating subsystem, and master control subsystem are included. A market analysis and development plan are given. (WHK)

1980-04-01

467

Laser Based In Situ Techniques: Novel Methods for Generating Extreme Conditions in TEM Samples  

Energy Technology Data Exchange (ETDEWEB)

The Dynamic Transmission Electron Microscope (DTEM) is introduced as a novel tool for in situ processing of materials. Examples of various types of dynamic studies outline the advantages and differences of laser-based heating in the DTEM in comparison to conventional (resistive) heating in situ TEM methods. We demonstrate various unique capabilities of the drive laser, namely, in situ processing of nanoscale materials, rapid and high temperature phase transformations, and controlled thermal activation of materials. These experiments would otherwise be impossible without the use of the DTEM drive laser. Thus, the potential of the DTEM to as a new technique to process and characterize the growth of a myriad of micro and nanostructures is demonstrated.

2008-02-25

468

LET-dependence of the trapping parameters in TLD-100 determined with a computerised curve fitting method  

International Nuclear Information System (INIS)

With a computerized curve fitting method the trapping parameters of TLD-100 chips were calculated after #alpha#-, #beta#- and #gamma#-irradiation. The absorption of radiation produces an additional glow peak at 250 deg C, and the dominant one arises at 280 deg C. After the analysis of the glow curves only a little LET-dependence of the trap depths and that of the half widths was detected. The charge densities after irradiation before heating of the taps responsible for the high temperature glow peaks (T>240 deg C) show a LET-dependence. (author).

1985-10-22

469

Inhibitors of steel corrosion in hydrochloric acid at high temperature  

Science.gov (United States)

A proposed inhibitor for steel corrosion in hydrochloric acid consists essentially of 0.5% of an inhibitor called BA-6, 0.25-0.5% of 1-hexynol-3, and about 0.02% of potassium iodide (calculated on the amount of acid). The inhibitor DA-6 is produced by condensing benzylamine with utrotropine. 1-Hexynol-3, secondary alcohol, is obtained from butyraldehyde and acetylene in the presence of caustic potash. The increase of potassium iodide concentration from 0.02-0.1% increases the protective action of the inhibitor. Hexynol, dipropargyl ester, and potassium iodide must be introduced in HC1 before injection of the latter into the well.

1965-01-07

470

Infrared spectroscopy analysis of MgO-doped silicon nitride  

Energy Technology Data Exchange (ETDEWEB)

Silicon nitride hybrid ball bearings used in high temperature applications undergo mechanical and environmental degradation. To study the surface chemistry of silicon nitride, a CAChe{trademark} Worksystem* has been used to generate the clusters and corresponding transmission vibrational spectra of silicon nitride. In the present study, the effect of surface conditions on the surface chemistry and wear degradation of silicon nitride was evaluated. Infrared reflection spectroscopy (IRRS) used to determine molecular orientations shows a difference in reflectance spectra for fractured and as-received.

1997-12-31

471

Hydrothermal industrialization electric-power systems development. Final report  

Energy Technology Data Exchange (ETDEWEB)

The nature of hydrothermal resources, their associated temperatures, geographic locations, and developable capacity are described. The parties involved in development, required activities and phases of development, regulatory and permitting requirements, environmental considerations, and time required to complete development activities ae examined in detail. These activities are put in proper perspective by detailing development costs. A profile of the geothermal industry is presented by detailing the participants and their operating characteristics. The current development status of geothermal energy in the US is detailed. The work on market penetration is summarized briefly. Detailed development information is presented for 56 high temperature sites. (MHR)

1982-03-01

472

High efficiency USC power plant - present status and future potential  

Energy Technology Data Exchange (ETDEWEB)

Increasing demand for energy production with low impact on the environment and minimised fuel consumption can be met with high efficient coal fired power plants with advanced steam parameters. An important key to this improvement is the development of high temperature materials with optimised mechanical strength. Based on the results of more than ten years of development a coal fired power plant with an efficiency above 50 % can now be realised. Future developments focus on materials which enable an efficiency of 52-55 %. (orig.) 25 refs.

1998-12-31

473

Handling of sodium for the FFTF  

Science.gov (United States)

Based on the High Temperature Sodium Facility (HTSF) experience and the extensive design efforts for FFTF, procedures are in place for the unloading of the tank cars and for the fill of the FFTF reactor. Special precautions have been taken to provide safe handling and to accommodate contingencies in operation. These contingencies include special protective suits allowing personnel to enter and correct conditions arising from fill operations in the course of moving 7.71 x 10/sup 5/ kg (1.7 x 10/sup 6/ lbs) of sodium from the tank cars into the reactor vessel and its loop system.

1978-06-01

474

Full-length fuel rod behavior under severe accident conditions  

Energy Technology Data Exchange (ETDEWEB)

This document presents an assessment of the severe accident phenomena observed from four Full-Length High-Temperature (FLHT) tests that were performed by the Pacific Northwest Laboratory (PNL) in the National Research Universal (NRU) reactor at Chalk River, Ontario, Canada. These tests were conducted for the US Nuclear Regulatory Commission (NRC) as part of the Severe Accident Research Program. The objectives of the test were to simulate conditions and provide information on the behavior of full-length fuel rods during hypothetical, small-break, loss-of-coolant severe accidents, in commercial light water reactors.

1992-12-01

475

Final report on the project entitled: Highly Preheated Combustion Air System with/without Oxygen Enrichment for Metal Processing Furnaces  

Energy Technology Data Exchange (ETDEWEB)

This work develops and demonstrates a laboratory-scale high temperature natural gas furnace that can operate with/without oxygen enrichment to significantly improve energy efficiency and reduce emissions. The laboratory-scale is 5ft in diameter & 8ft tall. This furnace was constructed and tested. This report demonstrates the efficiency and pollutant prevention capabilities of this test furnace. The project also developed optical detection technology to control the furnace output.

2007-02-16

476

Feedwater control device of the steam generator in an atomic power station  

International Nuclear Information System (INIS)

Purpose: In a case of automatically controlling the water level at the time of generating a lower power, to impact the followability of the control necessary for the power variation of the steam generator thereby to obtain good controllability. Constitution: A signal of deviation of water level of a steam generator and its set value and a signal of a difference between the temperature of the primary coolant in the high temperature side pipeline and that of the primary coolant in the low temperature side pipeline are used to automatically or manually control the flow quantity of water fed to the steam generator. (Yoshihara, H.).

477

Experimental study on the volatile ruthenium decontamination factor of the perforated plate column scrubber  

International Nuclear Information System (INIS)

During a high temperature treatment of the radioactive wastes that contain ruthenium, some ruthenium is volatilized and released to the off gas system. The volatilized ruthenium is removed with a scrubber and an adsorber. It was expected that the scrubber was one of the most effective equipments to remove ruthenium and the decontamination factor of the scrubber was studied. The experimental apparatus was simulated as part of an actual perforated plate column scrubber. The non-radioactive ruthenium which simulated the radioactive ruthenium was volatilized and fed into the scrubber. The decontamination factor of the scrubber was determined by the ratio of the ruthenium concentration at the inlet and outlet of the scrubber off gas stream. The results showed that the scrubber removed the volatile ruthenium effectively as expected.

1993-07-01

478

Experimental Proof Of Principle For The Link-Up Of A Solid Oxide Fuel Cell With A Counter-Current Wood Gasifier  

Energy Technology Data Exchange (ETDEWEB)

The combination of wood gasification and high temperature fuel cells like solid oxide fuel cells (SOFC) is an interesting approach to achieve high electrical efficiencies (40%) in small scale combined heat and power plants. This combination is called 'Biomass - Integrated Gasification Fuel Cell System' (B-IGFC). The main challenge is the adjustment of the three main components gasification, gas cleaning and fuel cell. In this technology, the first proof of principle by combining a gasifier with a SOFC in a laboratory scale for more than 100 hours was achieved. During this period, no deactivation of the system was found. (author)

2005-03-01

479

Engineering study on steam storage power generation. System screening and efficiency  

Energy Technology Data Exchange (ETDEWEB)

Large scale steam storage power generation, one of the new energy storage systems for the future of inflexible electric power sources consisting of nuclear and coal power plants has been studied on the subjects of the systems to be attached to coal and nuclear power units, of the definition of storage efficiency and of the vertical steam storage vessel technology. Steam storage power generation may be hopeful for its higher efficiency similarly defined as of pumped storage plants while high temperature heat storage and the internal structure of large vertical steam storage vessel (accumulator) need to be developed.

1981-11-01

480

Engineering study on steam storage power generation  

International Nuclear Information System (INIS)

Large scale steam storage power generation, one of the new energy storage systems for the future of inflexible electric power sources consisting of nuclear and coal power plants has been studied on the subjects of the systems to be attached to coal and nuclear power units, of the definition of storage efficiency and of the vertical steam storage vessel technology. Steam storage power generation may be hopeful for its higher efficiency similarly defined as of pumped storage plants while high temperature heat storage and the internal structure of large vertical steam storage vessel (accumulator) need to be developed. (author).

1981-01-01

481

Energetical analysis of sensitivity of hydrogen embrittlement of ordered alloys  

Science.gov (United States)

Intermetallic compounds are regarded as highly promising for applications as high temperature structural materials. However, recent studies have demonstrated that a number of ordered alloys exhibit environmental embrittlement when tested in various environments at ambient temperature. When exposed to hydrogen gas or electrolytically charged with hydrogen, a significant ductility loss has been reported. The reaction of water vapor with reactive elements in the crack tip results in the generation of atomic hydrogen which diffuses from the surface to the interior and causes embrittlement. In this paper, the authors try to analyze the sensitivity of hydrogen embrittlement of ordered alloys based upon energetical considerations.

1993-10-01

482

Emittance theory for thin film selective emitter  

Energy Technology Data Exchange (ETDEWEB)

Thin films of high temperature garnet materials such as yttrium aluminum garnet (YAG) doped with rare earths are currently being investigated as selective emitters. This paper presents a radiative transfer analysis of the thin film emitter. From this analysis the emitter efficiency and power density are calculated. Results based on measured extinction coefficients for erbium-YAG and holmium-YAG are presented. These results indicated that emitter efficiencies of 50 percent and power densities of several watts/sq cm are attainable at moderate temperatures (less than 1750 K).

1994-08-01

483

Electric cars: No-noise and low-pollution. Elektroautos. Laermfrei und schadstoffarm  

Energy Technology Data Exchange (ETDEWEB)

Growing ecological awareness in the car industry resulted in further developments of the otto and diesel engines, and of alternative fuels like cars with electric drive. This article gives an overview on a number of pertinent developments. The possible uses of electric cars are still limited by the battery in terms of storage capacity, output, service life and weight so that for the time being their use can be expected to be restricted to public and local-authority antreprises or to companies driving within city areas preferably. A break-through is expected by the industry in the field of high-temperature batteries although there are still a number of problems unsolved. (BWI).

1991-01-01

484

Effect of protective coatings on the high-temperature fatigue of heat-resistant alloys  

Energy Technology Data Exchange (ETDEWEB)

The fatigue properties of EP539LM alloy with an Al-Nb-Si fused slurry coating and a Co-Cr-Al-Y electron-beam coating are investigated experimentally in vacuum and in air at 900 C. It is found that the protective coatings reduce the fatigue life of the specimens both in vacuum and in air, with the electron-beam coating affecting the fatigue life of the alloy to a lesser degree than the fused slurry coating. The negative effect of the coatings on the fatigue life of the alloy is attributed largely to the properties of the coating material. 7 references.

1986-08-01

485

Drilling mud for application during the drilling of caving-prone rock  

Energy Technology Data Exchange (ETDEWEB)

The authors propose a drilling solution for use in caving-prone rock formations. This solution contains clay, hydrolized polyacrylonitrile, and water. In order to improve the solution's inhibitive properties during high-temperatures, azodicarbonamide (the blowing agent ChKhZ-21) is introduced in adequate quantities. The solution's makeup is as follows, given by percentage of weight,-- Clay 5-8%; hydrolized polyacrylonitrile 0.1-0.5%; azodicarbonamide (the blowing agent ChKhZ-21) 1-3%, with the remainder being water.

1981-01-01

486

Development of ALLOY 800 for PWR/SG tubings resistant to IGSCC and general corrosion  

Energy Technology Data Exchange (ETDEWEB)

Resistance of ALLOY 800 as a PWR/SG tubings to IGC/IGSCC and Ni, Co release into high temperature water was evaluated as compared with ALLOYs 600 and 690. The study to improve the resistance to IGSCC and general corrosion was also made. From the results, ALLOY 800 was evaluated to be the most reliable among the high Ni alloys tested. In addition, the alloy would obtain further reliability in IGSCC and general corrosion resistance by the combined addition of Ti and Nb, and the prior oxidation treatments, respectively. (author).

1989-07-01

487

Design criterion for tubed solar-heated cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

Solar energy can be economically converted into electrical energy for small and medium power outputs. A typical solar power plant consists of a parabolic dish, cavity receiver and gas turbine. To obtain high gas turbine efficiences, the working fluid used has to be heated to high temperatures. This necessitates the use of expensive high-quality materials for the tubes in the receiver. This expense must be kept to a minimum. The present paper demonstrates how this aim can be achieved by meeting the so-called Bammert Criterion.

1986-07-01

488

Design criterion for tubed solar-heated cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

Solar energy can be economically converted into electrical energy for small and medium power outputs. A typical solar power plant consists of a parabolic dish, cavity receiver and gas turbine. To obtain high gas turbine efficiencies, the working fluid used has to be heated to high temperatures. This necessitates the use of expensive high-quality materials for the tubes in the receiver. This expense must be kept to a minimum. The present paper demonstrates how this aim can be achieved by meeting the so-called Bammert Criterion.

1986-01-01

489

Dependence of thermal plasma jet temperature on discharge power and gas flow rate  

International Nuclear Information System (INIS)

With the help of heat balance equation and high temperature thermodynamic function, the calibration relation of jet temperature with discharge power, gas flow rate was obtained for nitrogen thermal plasma. It was shown that the results were agreed with the principle of similarity. The jet temperature was a function of Peff/f, instead of a general two variables function of Peff and f, which were effective discharge power and working gas flow rate, respectively. A related discussion has been given; it will be referable to thermal plasma applications. (authors)

2008-03-01

490

Damage mechanism in high temperature fatigue of alloy 800 H  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the influence of grain boundary cavities on the life time of Alloy 800 H various fatigue tests have been performed at 800/sup 0/C. Cavity formation has been observed only in asymmetrical tests. Compared to the corresponding symmetrical tests, the cyclic life time is shorter. As the cavitation damage increases, the ratio of life times in vacuum and in air steadily decreases from an initial value of 5. In extreme cases it can reach a value close to 1. In this case, cavitation damage dominates over the usual damage mechanism, which is cracks from the surface.

1986-09-01

491

Corrosion 2003. Conference papers on CD-ROM  

Energy Technology Data Exchange (ETDEWEB)

Papers are presented under 38 symposia. Subjects included reinforced concrete, protective coatings and linings, cathodic/anodic protection, chemical cleaning of boilers, managing corrosion with plastics, water treatment, HRSG boiler tube failure analysis, corrosion in oil and gas production, corrosion in petroleum refining and gas, processing, pipelines and tanks, high temperature materials, chemical process industry, aerospace equipment, materials technology developments for incinerators and waste fuel-fired processors, materials and corrosion in fossil-fuels conversion and combustion, corrosion in nuclear systems, marine corrosion, building systems, corrosion mechanisms, corrosion inhibitors and corrosion monitoring and measurement.

2003-07-01

492

Component design for LMFBR's  

Science.gov (United States)

Just as FFTF has prototype components to confirm their design, FFTF is serving as a prototype for the design of the commercial LMFBR's. Design and manufacture of critical components for the FFTF system have been accomplished primarily using vendors with little or no previous experience in supplying components for high temperature sodium systems. The exposure of these suppliers, and through them a multitude of subcontractors, to the requirements of this program has been a necessary and significant step in preparing American industry for the task of supplying the large mechanical components required for commercial LMFBR's. (auth)

1975-01-01

493

Combined cycle power plants with an integrated HTW-brown gasification  

International Nuclear Information System (INIS)

Despite the fact that there is still a potential to improve the efficiency of classic brown coal power plants by various measures from 36% to approx. 40-41%, the essential big increase of the efficiency to values of approx. 46% can only be achieved by the transition to combined gas and steam turbine processes. This means for the solid fuel brown coal that a gasification is integrated into the power plant process. The combined cycle power plant with an integrated brown coal gasification represents this new power plant concept. The applied High Temperature Winkler method (HTW-method) is an advancement of the Winkler method that works at environmental pressure and was developed by the Rheinbraun AG. (orig./DG).

494

Chemical decontamination methods for coatings  

Energy Technology Data Exchange (ETDEWEB)

A review of chemical decontamination methods for coatings indicates the following: the ease of both contamination and decontamination is a function of the radionuclide and the pH of the environment; the coating type is important in determining whether the contamination is loosely adsorbed, complexed, or contained in porous filler material; the condition of the coating is important to the decontamination factor obtained. Thus coatings can be decontaminated provided the solvent is sufficiently acid to solubilize the radionuclide and the complexant strength of the solvent is greater than that of the coating. Difficulties arise if the contamination is associated with fillers. Furthermore, though nothing has been said about temperature, decontamination of metal goes faster and, usually, with better efficiency at high temperatures. 11 references, 3 figures.

1984-05-01

495

Change in high-temperature strength properties of 12Kh1MF steel in long-term loading under creep conditions  

Energy Technology Data Exchange (ETDEWEB)

Stress-rupture strength tests were made of metal steam pipe (12Kh1MF steel) in various conditions, the original, after aging under laboratory conditions (580{degrees}C, 10,000 h), and after long service. It was shown that the more the steel is hardened by heat treatment or cold plastic working in the original condition, the less it hardens in creep. It was established that softening in creep of steel with a moderate yield strength is caused primarily by aging and with a high yield strength by pore formation.

1995-01-01

496

BNES materials conference a status review of alloy 800  

International Nuclear Information System (INIS)

Existing applications of Alloy 800 are summarized, with particular reference to its use in various types of reactor. The need for a co-ordinated research and development programme is stressed, and the variables to be explored are outlined. The papers relating to the problem of corrosion and cracking in water and steam are considered. the strength and ductility of Alloy 800 is considered. Finally, sections of the summary deal with the use of Alloy 800 for (a) sodium cooled fast reactor boiler tubes; (b) the high temperature gas cooled reactor; and (c) PWR steam generator tubes. (U.K.).

497

Asbestos: Industrial applications and precautions. (Latest citations from Information Services in Mechanical Engineering data base). Published Search  

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations concerning the properties, industrial uses and federal regulation of asbestos. The references explore advantages and disadvantages associated with use of industrial robots in areas containing high concentrations of asbestos dust, the use of water as a cutting tool to control the generation of asbestos dust, and governmental policies and attitudes relative to the health and welfare of workers subjected to asbestos. Thermal insulation properties, wear characteristics, high temperature capabilities, use as a reinforcement in composite materials, and asbestos substitutes are included. (Contains a minimum of 69 citations and includes a subject term index and title list.)

1992-07-01

498

A small particle selective emitter for thermophotovoltaic energy conversion  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an analysis of the performance of a selective emitter using small particles of rare earth compounds stable at high temperatures in a low emittance inert gas stream. An expression for the spectral emissive power excluding radiation scattering was derived to include the radiation in the emission band, produced by electronic transitions of the rare earth ion, and the continuum radiation outside the emission band produced by the rare earth host. Preliminary results suggest that a selective emitter based on suspended rare earth oxide particles will have high efficiency and merits further experimental investigation. {copyright} {ital 1996 American Institute of Physics.}

1996-02-01

499

A review of the behaviour of alloy 800 in liquid sodium  

International Nuclear Information System (INIS)

Although there is service experience of Alloy 800 as tubing for superheaters in conventional and nuclear (HTR) power stations and in PWR heat exchangers, there is no corresponding service experience in sodium-cooled fast reactor steam generators. However, some limited experimental studies have been made of corrosion behaviour, and of possible structure modifications and effects on mechanical properties which occur during exposure of this material to a high temperature sodium environment, and these are summarised in the paper. It is concluded that further work needs to be done before Alloy 800 can be confidently endorsed for use as tubing in fast reactor steam generators. (author).

500

A correlation between electrochemical parameters and stress corrosion cracking of alloy 600 in high temperature caustic solution  

International Nuclear Information System (INIS)

The properties of the passive films formed on Alloy 600 at different applied potentials in 10% NaOH solution at 315 .deg. C was studied using in situ AC impedance and polarization measurements. The results were correlated with the stress corrosion cracking (SCC) behavior obtained from the C-ring tests in the same conditions. The change of the semiconductive property and the peak of relaxation time were observed at 0.2 V where the SCC rate showed a maximum. These results were also consistent with the prediction parameter for SCC obtained from fast and slow polarization scans.

2001-10-01