WorldWideScience
1

Revisited the mathematical derivation wall thickness measurement of pipe for radiography  

Energy Technology Data Exchange (ETDEWEB)

Wall thickness measurement of pipe is very important of the structural integrity of the industrial plant. However, the radiography method has an advantage because the ability of penetrating the insulated pipe. This will have economic benefit for industry. Moreover, the era of digital radiography has more advantages because the speed of radiographic work, less exposure time and no chemical used for film development. Either the conventional radiography or digital radiology, the wall thickness measurement is using the tangential radiography technique (TRT). In case, of a large diameter, pipe (more than inches) the determination maximum penetration wall thickness must be taken into the consideration. This paper is revisited the mathematical derivation of the determination of wall thickness measurement based on tangential radiography technique (TRT). The mathematical ...

2007-07-01

2

Structural integrity of whipping pipes following a postulated circumferential break - a contribution to determining strain levels acceptable under faulted conditions  

Energy Technology Data Exchange (ETDEWEB)

It is postulated that a break of a thin-walled pipe does not cause a subsequent break in the pipe in the vicinity of a plastic hinge even when the wall is weakened by a 60 circumferential crack of a depth of 30% of the wall thickness on the tension side. This pipe behavior is the result of plastic buckling in the compression side and applies to pipes of diameter-to-thickness ratio larger than 20. For this type of pipe, the axial strains decrease with increasing diameter-to-thickness ratio in the tension side. As the pipe is only loaded in one direction, there is no cyclic behavior that can trigger a subsequent break. (orig.)

1993-10-01

3

An evaluation of the embedment of a Radio Frequency Integrated Circuit with a temperature detector in building envelopes for energy conservation  

British Library Electronic Table of Contents (United Kingdom)

Concrete is the primary material for building envelopes in some parts of the world, and its ability to store heat as well as its dynamic temperature changes will not only affect the deterioration rate of the exterior wall but will also greatly influence the energy efficiency of interior air conditioning. There are many methods for measuring the inner temperature of concrete, but they often have limitations, such as indirect estimation, cable installation requirements, high cost, or heterogeneity of the sample structure. In order to measure the internal temperature of concrete, this study integrated a Radio Frequency Integrated Circuit (RFIC) with a temperature sensor chip and embedded the device in concrete structures. A Smart Temperature Information Material (STIM) was thus developed. Thi...

2011-01-01

4

The Structure of Plant Cell Walls  

UK PubMed Central (United Kingdom)

The molecular structure, chemical properties, and biological function of the xyloglucan polysaccharide isolated from cell walls of suspension-cultured sycamore (Acer pseudoplatanus)...Full Text Available

1973-01-01

5

Evaluation of pipe whip impacts on neighboring piping and walls of the Ignalina Nuclear Power Plant  

Energy Technology Data Exchange (ETDEWEB)

Stress corrosion cracks have been discovered in Group Distribution Headers (GDH) at the Ignalina and Chernobyl Nuclear Power Plants. This increases the probability that a guillotine pipe break can occur that creates a whipping pipe (GDH) with the potential to damage surrounding structures-i.e. adjacent GDH and its attached piping or adjacent reinforced concrete compartment wall. The GDH is the most important component for reactor safety in case of an accident. Emergency Core Cooling System (ECCS) piping is connected to the GDH piping such that, during an accident, coolant passes from the ECSS into the GDH. Presented in this paper is the transient analysis of a Group Distribution Header following a guillotine break at the blind end of the header. Using a very conservative force loading function, the transient response of a whipping RBMK-1500 GDH along with neighboring concrete walls and pipelines is obtained using finite ...

2007-04-15

6

Reliability analysis of pipe whip impacts  

Energy Technology Data Exchange (ETDEWEB)

A probability-based approach is presented as the integration of probabilistic methods and deterministic modelling based on the finite element method. An existing finite element software package was linked to an existing probabilistic package to analyse the complex mechanics that occur during the transient non-linear analysis of impact problems. This methodology is applied to a pipe whip analysis of a group-distribution-header, which results from a guillotine break, and subsequent impact with the adjacent building wall; this is a postulated accident for the Ignalina Nuclear Power Plant RBMK-1500 reactors. The uncertainties of material properties, component geometry data and loads were taken into consideration. The probabilities of failure of the impacted header and of the header support-wall were estimated given uncertainties in material properties, geometrical parameters and loading. The software ProFES was used for the ...

2005-08-01

7

SPACE STATION INTEGRATED WALL DESIGN AND PENETRATION  

Science.gov (United States)

screens of fine wire was placed between the gun barrel and the panel to determine whether the gun performance was repeatable. The transducers were placed ...

8

Applicability of structural wall test results to seismic design of nuclear facilities  

International Nuclear Information System (INIS)

A review of tests on earthquake-resistant reinforced concrete structural walls is presented. Laboratory tests of isolated walls and construction joints are discussed. Where appropriate, design recommendations are given. The review indicates only few experimental data are available for short walls which are directly applicable to nuclear power plant design. In particular, tests of short rectangular walls subjected to load reversals are needed. Tests are also needed to determine the damping and frequency characteristics of cracked short walls. Analytical and experimental results should be correlated so that the hysteretic response observed in tests can be realistically related to the analytical response 'demand' of nuclear power plant structures. (Auth.).

9

Safety System Design Concept and Performance Evaluation for a Long Operating Cycle Simplified Boiling Water Reactor  

Science.gov (United States)

The long operating cycle simplified boiling water reactor is a reactor concept that pursues both safety and the economy by employing a natural circulation reactor core without a refueling, a passive decay heat removal, and an integrated building for the reactor and turbine. Throughout the entire spectrum of the design basis accident, the reactor core is kept covered by the passive emergency core cooling system. The decay heat is removed by the conventional active low-pressure residual heat removal system. As for a postulated severe accident, the suppression pool water floods the lower part of the reactor pressure vessel (RPV) in the case when core damage occurs, and the in-vessel retention that keeps the melt inside the RPV is achieved by supplying the coolant. The containment adopts a parallel-double-steel-plate structure similar to a hull structure, which contains coolant between the inner and outer ...

2003-07-15

10

Development of an inactive heat removal system for high temperature reactors  

International Nuclear Information System (INIS)

Growing public and political interests towards incorporating passive safety features in nuclear installations, let Siempelkamp in late 1987 propose a solution consisting of a prestressed cast-iron pressure vessel and a passive heat removal system, integrated in the reactor cell surrounding the vessel. This solution combines the inherent safety of a prestressed metallic pressure vessel with the advantages of a passive heat removal system and thus constitutes a major step towards the goal of further reducing potential residual risks. The design had to meet the boundary conditions for reactor core and reactor building of the modular 200 MWth pebble bed reactor of Siemens/-KWU. The engineering design showed that many input parameters needed for the finite-element-analysis of the overall structure required a verification by measurements in a well scaled test setup. This was especially required for the heat transfer from the liner of the prestressed ...

1994-08-01

11

Challenges of Aircraft Design Integration  

Science.gov (United States)

... The program generates conceptual layouts of wing structural components and creates a beam finite element model of the wing structure (Figure 6 ...

2003-03-01

13

Structural integrity evaluation of FTL in-pool piping  

Energy Technology Data Exchange (ETDEWEB)

HANARO fuel test loop will be equipped in HANARO to obtain the development betterment of advanced fuel and materials through the irradiation test. The object of this study is to evaluate the structural integrity of FTL in-pool piping by investigating a dynamic analysis of the loop containing a postulated rupture section. The method to perform the dynamic analysis and structural integrity evaluation caused by the pipe whip in water environment can be a reference for a similar structural integrity evaluation. (author). 7 refs., 39 tabs., 34 figs.

1998-05-01

14

Magnetohydrodynamic structure of a plasmoid in fast ... - NASA  

Science.gov (United States)

We set a symmetric boundary at x=200 and a conducting wall at z=150. The domain of 0200. 0150 is resolved by 60004500 grid cells. Harris sheet ...

15

The two-dimensional Stefan problem with slightly varying heat flux  

Science.gov (United States)

The authors solve the two-dimensional stefan problem of solidification in a half-space, where the heat flux at the wall is a slightly varying function of positioning along the wall, by means of a large Stefan number approximation (which turns out to be equivalent to a small time solution), and then by means of the Heat Balance Integral Method, which is valid for all time, and which agrees with the large Stefan number solution for small times. A representative solution is given for a particular form of the heat flux perturbation.

1995-09-01

16

CFD Application to the Regulatory Assessment of FAC-Caused CANDU Feeder Pipe Wall Thinning Issue  

Energy Technology Data Exchange (ETDEWEB)

From the results of the In-Service Inspection (ISI) measuring the wall thickness of outlet (hot-leg side) feeder pipes performed at two Canadian nuclear power plants, Point Lepreau and Gentilly-2 in 1995 and 1996, respectively, the wall thinning degradation of feeder pipes at the bend part was found to be much more severe than expected. It has been well known that such wall thinning of feeder pipes is caused by the flow accelerated corrosion (FAC) which is one of the mechanical-chemical degradation mechanisms affecting the integrity of piping systems. For the Wolsung unit 1, the wall thickness measurements have been performed during every overhaul period since 1996. The wall thinning rates at the bends of outlet feeder pipes were assessed to exceed the design value. However, for the Wolsung units 2, 3 and 4, the wall thinning rates of all ...

2007-07-01

17

CFD Application to the Regulatory Assessment of FAC-Caused CANDU Feeder Pipe Wall Thinning Issue  

International Nuclear Information System (INIS)

From the results of the In-Service Inspection (ISI) measuring the wall thickness of outlet (hot-leg side) feeder pipes performed at two Canadian nuclear power plants, Point Lepreau and Gentilly-2 in 1995 and 1996, respectively, the wall thinning degradation of feeder pipes at the bend part was found to be much more severe than expected. It has been well known that such wall thinning of feeder pipes is caused by the flow accelerated corrosion (FAC) which is one of the mechanical-chemical degradation mechanisms affecting the integrity of piping systems. For the Wolsung unit 1, the wall thickness measurements have been performed during every overhaul period since 1996. The wall thinning rates at the bends of outlet feeder pipes were assessed to exceed the design value. However, for the Wolsung units 2, 3 and 4, the wall thinning rates of all ...

2007-05-10

18

Magnetization reversal phenomena and domain wall behaviours in nanostructured magnetic systems  

International Nuclear Information System (INIS)

Several recent experiments on micro- (or nano-) structured samples of ferromagnetic materials are introduced. Magnetization reversal phenomena are investigated on submicron wire samples of trilayer structure using the giant magnetoresistance effect. Domain wall movements are sensitively monitored by resistivity measurements and the velocity of propagation is determined. The contribution of domain wall to the resistivity is argued from the results on artificially designed samples of a spring-magnet system. In circular dots of permalloy, the existence of vortex magnetization is confirmed and the reversal of the vortex core magnetization is studied from magnetic force microscopy measurements. (author)

2001-09-23

19

Elastodynamics of vehicles and crash simulation  

Energy Technology Data Exchange (ETDEWEB)

Accidents of free-rolling cars against walls with friction are special cases of the general problem of the dynamic behavior (elastic or plastic) of car motion. Using particle modeling of the car body it is shown that large rotations, contact friction and plastic deformations can be computed. Because of the limitations of FEM it is necessary to model the car as a system of mass points connected by central force systems which are non-linear. The wall is formulated as a rigid body producing constraints for the contacting particles, while the contact force is given by the defined force system. Every contacting particle produces a plastic impact on the wall. The friction force is proportional to the contact force and lies in the direction of the sliding velocity on the wall. Time integration is carried out using a second order Gear method. ((orig.))

1994-09-30

20

Fabrication and testing of small scale mock-ups of ITER shielding blanket  

International Nuclear Information System (INIS)

Small scale mock-ups of the primary first wall, the baffle first wall, the shield block and a partial model for the edge of the primary first wall module were designed and fabricated incorporating most of the key design features of the ITER shielding blanket. All mock-ups featured the DSCu heat sink, the built-in SS coolant tubes within the heat sink and the SS shield block. CFC tiles was used as the protection armor for the baffle first wall mock-up. The small scale shield block mock-up, integrated with the first wall, was designed to have a poloidal curvature specified in the ITER design. Fabrication routes of mock-ups were decided based on the single step solid HIP of DSCu/DSCu, DSCu/SS and SS/SS reflecting the results of previous joining techniques development and testing. For attaching the CFC tiles onto DSCu heat sink in the fabrication of the baffle first ...

1998-09-01

21

Pressure-induced structural transitions in multi-walled carbon nanotubes  

British Library Electronic Table of Contents (United Kingdom)

We demonstrate a novel cross-sectional deformation, called the radial corrugation, of multi-walled carbon nanotubes (MWNTs) under hydrostatic pressure. Theoretical analyses based on the continuum elastic approximation have revealed that MWNTs consisting of more than ten concentric walls undergo elastic deformations at critical pressure Formula Not Shown , above which the circular shape of the cross-section becomes radially corrugated. Various corrugation modes have been observed by tuning the innermost tube diameter and the number of constituent walls, which is a direct consequence of the core-shell structure of MWNTs. Cross-sectional views of MWNT under high hydrostatic pressure: elliptic deformation with the mode index n = 2 (left), and radial corrugations with n = 5 (center), and n = 6 ...

2009-01-01

22

Structural integrity evaluation of fuel test loop submerged in water subjected to postulated pipe rupture  

Energy Technology Data Exchange (ETDEWEB)

The structural integrity of the Fuel Test Loop(FTL) in a Korean experimental reactor is evaluated when the FTL, submerged in a water environment, is subjected to a postulated pipe rupture. The analyses are performed under static and dynamic conditions, imposing the thrust force history at each postulated pipe rupture section. Through analysis the following results are found: 1) A double ended guillotine can not be expected based on the toughness of the material, 2) the structural integrity of the chimney surrounding the FTL would not impede the structural integrity by the pipe whip. All analyses are performed by finite element methods.

2000-02-01

23

Energy conservation by means of integrated systems; Beter resultaat door klimaatkwartet  

Energy Technology Data Exchange (ETDEWEB)

Air conditioning is getting maximum attention these days when building new offices. For the new office building of the assurance company Zwitserleven in Amstelveen, Netherlands, a new air conditioning concept is applied, based on four existing air conditioning methods: cold storage and heat storage in the soil, heat pump, double-wall facades with integrated climate control, and radiant heating combined with a cooling system in the ceiling. The integration of these methods not only provides complete climate comfort for the employees but also substantial energy savings. 3 figs.,1 ills.

1995-11-01

24

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank's structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated ...

1992-01-01

25

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank`s structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those ...

1992-01-01

26

Study on reactor building structure using ultrahigh strength materials - Part 7: Outline of mixed structure tests  

International Nuclear Information System (INIS)

The objective of this study is to comprehend the basic structural characteristics of box shaped mixed structures proposed for a future nuclear reactor building structure. Specimens of reinforced concrete precast panel walls of the mixed structures were prepared using ultrahigh strength materials. Two bending shear tests were conducted with a parameter of the quantity of reinforcement bars. The results include: (1) Relationship of shear stress and the angle of the structure, and (2) Failure mode. (author)

1993-08-15

27

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

28

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

Energy Technology Data Exchange (ETDEWEB)

The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

1985-05-01

29

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

International Nuclear Information System (INIS)

The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

30

High resolution scanning electron microscopy of plasmodesmata.  

Science.gov (United States)

Symplastic transport occurs between neighbouring plant cells through functionally and structurally dynamic channels called plasmodesmata (PD). Relatively little is known about the composition of PD or the mechanisms that facilitate molecular transport into neighbouring cells. While transmission electron microscopy (TEM) provides 2-dimensional information about the structural components of PD, 3-dimensional information is difficult to extract from ultrathin sections. This study has exploited high-resolution scanning electron microscopy (HRSEM) to reveal the 3-dimensional morphology of PD in the cell walls of algae, ferns and higher plants. Varied patterns of PD were observed in the walls, ranging from uniformly distributed individual PD to discrete clusters. Occasionally the thick walls of the giant alga Chara were fractured, revealing the surface morphology of PD within. External ...

2011-05-28

31

Functional and Structural Analysis of a Key Region of the Cell Wall Inhibitor Moenomycin  

UK PubMed Central (United Kingdom)

Moenomycin A (MmA) belongs to a family of natural products that inhibit peptidoglycan biosynthesis by binding to the peptidoglycan glycosyltransferases (PGTs), the enzymes that make the glycan...Full Text Available

2010-07-16

32

Taking the plunge: integrating structural, enzymatic and computational insights into a unified model for membrane-immersed rhomboid proteolysis  

UK PubMed Central (United Kingdom)

SYNOPSISRhomboid proteases are a fascinating class of enzymes that combine a serine protease active site within the core of an integral membrane protein. Despite having key roles...Full Text Available

33

Structural analysis of a hepatitis B virus genome integrated into chromosome 17p of a human hepatocellular carcinoma.  

UK PubMed Central (United Kingdom)

Hepatitis B virus (HBV) is clearly a factor in the development of hepatocellular carcinoma, but its mechanism of action remains obscure. One possibility is that the HBV integration event alters the...Full Text Available

1988-11-01

34

Style and magnitude of Mesozoic thrust faulting in the hinterland of the Sevier thrust belt Pequop Mountains-Wood Hills-East Humboldt Range region, northeast Nevada  

Energy Technology Data Exchange (ETDEWEB)

The Pequop Mountains (PM), Wood Hills (WH) and East Humboldt Range (EHR), NE Nevada, provide evidence that the hinterland of the Sevier thrust belt experienced large-magnitude Mesozoic shortening ([>=]55 km) and crustal thickening ([>=] 30 km). These ranges expose a structurally continuous crustal cross section of unmetamorphosed to high pressure upper amphibolite facies Triassic to Precambrian miogeoclinal strata. This sequence lies structurally beneath unmetamorphosed extensional klippen that omit metamorphic grade and crustal section, but also repeat stratigraphic units. Because they repeat stratigraphic units, the underlying miogeoclinal section, or footwall, must have once lain beneath a thrust fault (herein named the Windermere thrust). The footwall of the Windermere thrust was exhumed by two generations of top-to-the-W-NW low-angle normal faults that are distinguished by whether they are depositionally overlapped by Eocene volcanic ...

1993-04-01

35

Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities  

Energy Technology Data Exchange (ETDEWEB)

This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

1999-09-22

36

Classical fracture mechanics methods  

International Nuclear Information System (INIS)

Comprehensive Structural Integrity is a reference work which covers all activities involved in the assurance of structural integrity. It provides engineers and scientists with an unparalleled depth of knowledge in the disciplines involved. The new online Volume 11 is dedicated to the mechanical characteristics of materials. This paper contains the chapter 11.02 of this volume and is structured as follows: Test techniques; Analysis; Fracture behavior; Fracture toughness tests for nonmetals.

37

Study on reactor building structure using ultrahigh strength materials - Part 9: Summary of the study  

International Nuclear Information System (INIS)

Considerations for longevity of nuclear facilities and ease of decommissioning are of great importance for future nuclear power plants. To this end, a concept of an optimal structural concept for nuclear reactor buildings has been studied: the main feature of this concept is to utilize large-sized, light weight prefabricated members with ultrahigh strength materials. The following two items have been selected to study the prospective structure: (1) Applicability of ultrahigh strength materials for reinforced concrete shear walls (2) Construction using large sized prefabricated members As the first step (1), material and structural tests using ultrahigh strength materials, and the subsequent analysis of those tests for reinforced concrete shear walls, has been conducted. The positive results of this study show a bright future for the use of ultrahigh strength materials for the ...

1993-08-15

38

Design of Damage-Tolerant Composite Sandwich Panels with Tear Straps  

Science.gov (United States)

The objectives of the Phase-I research address the development of mechanics- based structural integrity analysis methodologies for composite sandwich panels ...

39

Simulation of electromechanical and thermomechanical loads on first wall mock-ups  

International Nuclear Information System (INIS)

During the operation of a tokamak, the first wall elements suffer very high heat fluxes. Heat is removed by internal cooling by means of water, helium or fluid metal. The resulting inhomogeneous temperature field cause internal stresses which, due to the pulsed operation are of cyclic nature. Additional mechanical stresses in the first wall may be caused by disruptions or vertical plasma movements. During theses events high currents are induced in the metallic part of the first wall which by their interaction with the magnetic field of the tokamak lead to mechanical forces. These electromechanical stresses may lie beyond the yield stress of the structural material. From the interaction of thermal and mechanical forces, a complex stress state is achieved which under certain circumstances may lead to premature failure and/or to progressive plastic deformations (ratcheting). In order to study the boundary ...

40

Evaluation of pipe whip impacts on neighboring piping and walls of the Ignalina nuclear power plant.  

Energy Technology Data Exchange (ETDEWEB)

Presented in this paper is the transient analysis of a Group Distribution Header (GDH) following a guillotine break at the end of the header. The GDH is the most important component of reactor safety in case of accidents. Emergency Core Cooling System (ECCS) piping is connected to the GDH piping such that, during an accident, coolant passes from the GDH into the ECCS. The GDH that is propelled into motion after a guillotine break can impact neighboring GDH pipes or the nearest wall of the compartment. Therefore, two cases are investigated: GDH impact on an adjacent GDH and its attached piping; and GDH impact on an adjacent reinforced concrete wall. A whipping RBMK-1500 GDH along with neighboring concrete walls and pipelines is modeled using finite elements. The finite element code NEPTUNE used in this study enables a dynamic pipe whip structural analysis that accommodates large displacements and ...

2002-02-26

41

A novel CFD/structural analysis of a cross parachute  

Energy Technology Data Exchange (ETDEWEB)

A novel CFD/structural analysis was performed to predict functionality of a cross parachute under loadings near the structural limits of the parachute. The determination of parachute functionality was based on the computed structural integrity of the canopy and suspension lines. In addition to the standard aerodynamic pressure loading on the canopy, the structural analysis considered the reduction in fabric strength due to the computed aerodynamic heating. The intent was to illustrate the feasibility of such an analysis with the commercially available software PATRAN.

1993-12-31

42

Levels of ICT use in teaching and administration  

DEFF Research Database (Denmark)

The computer facilities and the computer expertise at certain departments at Aalborg University made these departments natural starting points for integration of Information and Communication Technology (ICT) in their activities. This utilization and integration of ICT was not organized from the top or intermediate levels. It developed from the grassroots. Today Aalborg University as a whole can be said to be a truly ICT integrated institution. The quick development is to a high extent due to a structure with a finely distributed system of equipment, know-how and autonomy at all levels

2000-01-01

43

Transversal Stiffness and Young's Modulus of Single Fibers from Rat Soleus Muscle Probed by Atomic Force Microscopy  

UK PubMed Central (United Kingdom)

AbstractThe structural integrity of striated muscle is determined by extra-sarcomere cytoskeleton that includes structures that connect the Z-disks and M-bands of a sarcomere to sarcomeres...Full Text Available

2010-02-03

44

An analysis by low-angle neutron scattering of the structure of the acetylcholine receptor from Torpedo californica in detergent solution.  

UK PubMed Central (United Kingdom)

The acetylcholine receptor from the electric tissue of Torpedo californica is a large, integral membrane protein containing four different types of polypeptide chains. The structure of the purified...Full Text Available

1979-12-01

45

Summary of Uranium City, Saskatchewan remedial measures for radiation reduction with special attention to vent fan theory  

International Nuclear Information System (INIS)

Various remedial measures have been tried to lower radon levels in buildings in Uranium City. The methods used are source material removal, passive ventilation of crawl spaces, sub-floor ventilation, complete epoxy coating of the entire basement, sealants for floor-wall joints and cracks in basements, electrostatic precipitators, mechanical ventilation, and sealing and grouting concrete block plenums in basement walls. The type and condition of structures encountered in Uranium City as well as the relative isolation of the town indicate that mechanical ventilation is the most long-term cost-effective method.

1980-03-12

46

Domain wall pining in a jointed ferromagnetic nano-wire  

Energy Technology Data Exchange (ETDEWEB)

The magnetoresistance in an FeNi submicron-structure comprising two wires of 80 and 200 nm in width connected in series was measured at 77 K. When the external magnetic field was applied parallel to the wire axis, two switching fields corresponding to the distinct coercive force of the two wires were observed. When the external magnetic field was applied at an angle of {theta}>30 deg. to the wire axis one switching field was observed, indicating simultaneous magnetization reversal in both wires. This indicates that the domain-wall trapping around the joint can be controlled systematically in terms of the direction of the external magnetic field.

2004-05-01

47

Shielding options for the ITER conceptual design  

Energy Technology Data Exchange (ETDEWEB)

Several shield options were analyzed for the ITER conceptual design to minimize the nuclear responses in the toroidal field (TF) coils. The total nuclear heating in the physics phase and the insulator dose in the technology phase are the most critical parameters in the design process. The first shield option has type 316 stainless steel and water shielding material. Steel and water also serve as structural material and coolant, respectively. The second option is similar to the first except that borated water is used instead of ordinary water. The other two options include a small layer of lead or boron carbide (B{sub 4}C) at the back of the shield. The last three shield options were considered to reduce the nuclear heating in the toroidal field coils relative to the steel/water shield. An optimization process was performed taking into consideration the thermal-hydraulics and the engineering requirements to define the shield configuration. A careful ...

1989-10-01

48

Structural health monitoring of constrained tapered beamlike structures using natural frequencies and nodal points  

Science.gov (United States)

The integrity and safety of beam-like structures are dependent in part on their boundary conditions which can vary with time due to damage or aging. Structural health monitoring of such structures should therefore include attention to boundary conditions. Where the boundary conditions can be represented by a lumped spring then the identification of associated stiffness parameter values may be a means to quantifying the integrity of the support. This paper investigates such a method for identifying the equivalent translational and rotational stiffness of a constrained tapered beam-like structure. An analytical model of a beam of tapered width and thickness is adopted as a simplified representation of a tower-like structure. The model is used to explore in what scenarios natural frequencies and/or nodal points might be sufficiently sensitive ...

2011-07-01

49

An overview of the development of the first wall and other principal components of a laser fusion power plant  

International Nuclear Information System (INIS)

This paper introduces the JNM Special Issue on the development of a first wall for the reaction chamber in a laser fusion power plant. In this approach to fusion energy a spherical target is injected into a large chamber and heated to fusion burn by an array of lasers. The target emissions are absorbed by the wall and encapsulating blanket, and the resulting heat converted into electricity. The bulk of the energy deposited in the first wall is in the form of X-rays (1.0-100 keV) and ions (0.1-4 MeV). In order to have a practical power plant, the first wall must be resistant to these emissions and suffer virtually no erosion on each shot. A wall candidate based on tungsten armor bonded to a low activation ferritic steel substrate has been chosen as the initial system to be studied. The choice was based on the vast experience with these materials in a nuclear environment and the ...

2005-12-15

50

Study on reactor building structures using ultrahigh strength materials - Part 8: Results of mixed structure tests  

International Nuclear Information System (INIS)

The mixed structure of a nuclear reactor building is composed of SC-columns, S-beams, S-joints and PCa-panels. Following the last report (Part 7)[1], the main test results of the mixed structure, that is, the deformation mode, strain distribution and shear strength, are described. The S-joints using ultrahigh strength materials had no buckling nor shear slipping. The proposed mixed structure resisted the external horizontal forces under integrated uniformity among SC-columns, S-joints and PCa-panels. It could be confirmed that the mixed structure can be established. (author)

1993-08-15

51

The mechanism of uranium biosorption by Rhizopus arrhizus  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of elements is a little understood phenomenon exhibited by some types of even nonliving microbial biomass. A common fungus Rhizopus arrhizus has been reportd to take up uranium from adqueous solutions to the extent of 180 mg U/sup 6 +//g. The mechanism of uranium sequestering by this type of biomass was studied by using experimental techniques such as electron microscopy, x-ray energy dispersion analysis, IR spectroscopy, and supporting evidence was obtained for a biosorption mechanism consisting of at least three processes. Uranium coordination and adsorption in the cell-wall chitin structure occur simultaneously and rapidly whereas precipitation of uranylhdroxide within the chitin microcrystalline cell-wall structure takes place at a lower rate. Interference of Fe/sup 2/ and Zn/sup 2 +/ coions with uranium biosorption is indicated.

1982-02-01

52

Sheathed cold-formed steel housing: A seismic design procedure  

British Library Electronic Table of Contents (United Kingdom)

Nowadays, different research teams are engaged on experimental and theoretical studies having as main aim the evaluation of seismic performance of sheathed cold-formed steel frame structures. Although a relatively large number of experimental and theoretical studies are available, the development of useful tools for the seismic design should be improved. As an attempt to overcome this lack, this paper aims to present a structural design procedure that allows, through the definition of three design nomographs, the screw spacing and all the shear walls components to be obtained on the basis of linear dynamic or nonlinear static seismic analysis. In addition, a procedure for the prediction of the whole pushover response curve of sheathed cold-formed steel shear walls, which can be advantageou...

2009-01-01

53

Refinement and evaluation of crack-opening-area analyses for circumferential through-wall cracks in pipes  

Energy Technology Data Exchange (ETDEWEB)

Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet impingement shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. These leak rates depend on the crack-opening area of a through-wall crack in the pipe. In addition to LBB analyses, which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessing temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section 11. This study was requested by the NRC to review, evaluate, and refine current analytical models for crack-opening-area analyses of pipes with circumferential ...

1995-04-01

54

Axiomatic Design Approach for a Reactor Head Structure Assembly  

Energy Technology Data Exchange (ETDEWEB)

Korea Atomic Energy Research Institute (KAERI) has been developing the integral reactor. The reactor head structure assembly (RHSA) is the structure installed over the reactor cover. Due to the characteristics of an integral reactor, there are many instrument cables and power cables coming out from the reactor cover and main components. The RHSA provides an interface location to connect these cables from Architecture Engineer (AE) and System Designer (SD). It also prevents a pipe whip and it prohibits instruments from becoming missiles. In this research, the axiomatic design approach for the RHSA is performed.

2006-07-01

55

Diverter/bop system and method for a bottom supported offshore drilling rig  

Energy Technology Data Exchange (ETDEWEB)

A system is described adapted for alternative use as a diverter or a blowout preventer for a bottom supported drilling rig and adapted for connection to a permanent housing attached to rig structural members beneath a drilling rig rotary table, the permanent housing having an outlet connectable to a rig fluid system flow line. The system consists of: a fluid flow controller having a controller housing with a lower cylindrical opening and an upper cylindrical opening and a vertical path therebetween and a first outlet passage and a second outlet passage provided in its wall, a packing element disposed within the controller housing, and annular piston means adapted for moving from a first position to a second position, whereby in the first position the piston means wall prevents interior fluid from communicating with the outlet passages in the controller housing wall and in the second position the piston ...

1986-07-01

56

The analysis of temperature distribution for surveillance Capsule in reactor vessel of YGN unit 1  

International Nuclear Information System (INIS)

Generally, Hardening and irradiated brominating phenomena are occurred in the reactor vessel under operation conditions by atomic cavities and creation of impurity atoms which are led by high fast neutron flux. To assure the mechanical integrity of pressure vessel until the end of power plant life after monitoring the sample specimens on the vessel inside, a series of tests is performed over the retrieved surveillance capsule to examine the changes according to the plant operation in accordance with regulations. Monitoring surveillance capsules attached to neutron shield wall of outer core are consists of impact sample, tensile sample and temperature monitor

2007-05-10

57

Dynamic response of pipelines buried in back-filled trenches  

Energy Technology Data Exchange (ETDEWEB)

Dynamic response of pipelines buried in a back-filled rectangular trench in a semi-infinite medium has been investigated. The pipelines are modeled as long cylindrical shells of small thickness. By using the boundary integral representation and finite element method, we have studied the three-dimensional response to account for either pane P or SV wave incident at an arbitrary angle to the pipe-axis. In this paper numerical results are presented for the normal displacements, displacements along pipe-axis, and the hoop stresses in the pipe wall. It is shown that the response depends critically on the back-filled material as well as on the directions of propagation of the incident waves.

1991-08-01

58

Diverter/bop system and method for a bottom supported offshore drilling rig  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a system adapted for alternative use as a diverter or a blowout preventer for a bottom supported drilling rig and adapted for positioning beneath a rotary table of the drilling rig, the system comprising: a fluid flow controller having a controller housing with a lower opening and an upper opening and a vertical flow path therebetween and an outlet passage provided in its housing wall, and at least two bases. A method is described for installing a system adapted for alternative connection as a diverter or a blowout preventer for a bottom supported drilling rig positioned beneath a rotary table of the drilling rig after structural casing has been set in a borehole. The method comprises: positioning a first telescoping spool having a lower end and an upper end below the rotary table, the first spool having a first base disposed at its upper end, the first base having a port disposed in its wall; aligning ...

1987-03-03

59

Satellite power systems (SPS). LSST systems and integration task for SPS flight test article. Final report  

Energy Technology Data Exchange (ETDEWEB)

This research activity emphasizes the systems definition and resulting structural requirements for the primary structure of two potential SPS large space structure test articles. These test articles represent potential steps in the SPS research and technology development.

1981-02-01

60

Floating production and storage vessels - design analysis and operational issues: a handbook produced to accompany the Bentham Technical Training Courses  

Energy Technology Data Exchange (ETDEWEB)

These ten chapters present an overview of floating production, storage and offloading (FPSO) vessels, and examines deep water developments; hydrostatic stability; production, storage and offloading systems; the configuration and structure of flexible risers and umbilicals; the structural and global dynamic analysis of flexible riser and umbilicals; verification of FPSO structural integrity; vessel global loading and rigid body response; environmental loading and vessel response; and mooring systems. (UK)

1998-07-01

61

Ab initio molecular dynamics with born-oppenheimer and extended lagrangian methods using atom centered basis functions  

Energy Technology Data Exchange (ETDEWEB)

In ab initio molecular dynamics, whenever information about the potential energy surface is needed for integrating the equations of motion, it is computed 'on the fly' using electronic structure calculations. For Born-Oppenheimer methods, the electronic structure calculations are converged, whereas in the extended Lagrangian approach the electronic structure is propagated along with the nuclei. Some recent advances for both approaches are discussed.

2003-06-01

62

The Membrane Bound LRR Lipoprotein Slr, and the Cell Wall-Anchored M1 Protein from Streptococcus pyogenes Both Interact with Type I Collagen  

UK PubMed Central (United Kingdom)

Streptococcus pyogenes is an important human pathogen and surface structures allow it to adhere to, colonize and invade the human host. Proteins containing leucine rich repeats (LRR)...Full Text Available

63

PIV measurements of flow structures in a spray dryer  

DEFF Research Database (Denmark)

Stereoscopic Particle Image Velocimetry (PIV) measurements are made in horizontal planes in a simplified scale model of a spray dryer using water as fluid. The sample rate was sufficient to resolve phenomena at lower frequencies. Data reveal asymmetric velocity fields in both mean fields and dynamics. Data were analysed using Proper Orthogonal Decomposition (POD). An important periodic event is an elongation of the jet core cross section that results in a downstream displacement of the jet towards the chamber wall.

2011-01-01

64

Evaluations of half-bead weld repair procedures with thick-wall pressure vessels  

Science.gov (United States)

The results of research on the evaluation of the half-bead weld repair method for use on nuclear reactor components are reviewed from data obtained on thick-section test pieces and intermediate-size pressure vessels. Material properties, the magnitude of residual stresses and the structural behavior of flawed pressure vessels are being obtained to determine the adequacy of the weld repair method for application in thick-section components.

1978-01-01

65

The 17-M VAWT program  

Science.gov (United States)

The commercial potential of the 17 m, 100 kW Darrieus Vertical Axis Wind Turbine (VAWT) is discussed. Long term testing is in progress. As the first commercially adapted Darrieus turbines built by DOE, the superior cost, structural integrity, and output characteristics demonstrated by the prototypes appear particularly promising.

1981-01-01

66

Phosphorylation-dependent power output of transgenic flies: an integrated study.  

UK PubMed Central (United Kingdom)

We examine how the structure and function of indirect flight muscle (IFM) and the entire flight system of Drosophila melanogaster are affected by phosphorylation of the myosin regulatory light chain...Full Text Available

1997-12-01

67

Ordered Assembly of the Adhesive and Electrochemical Connections within Newly Formed Intercalated Disks in Primary Cultures of Adult Rat Cardiomyocytes  

UK PubMed Central (United Kingdom)

The intercalated disk (ID) is a complex structure that electromechanically couples adjoining cardiac myocytes into a functional syncitium. The integrity of the disk is essential for normal cardiac function,...Full Text Available

2010-01-01

68

Lattice W_N algebra and its quantization  

International Nuclear Information System (INIS)

We consider the integrable structure of the quantum lattice W_N algebras. We introduce the ultralocal Lax matrix, and show that the Yang-Baxter relation is satisfied with a Z_N invariant R-matrix. (orig.).

1997-11-01

69

Insulin receptor signaling in the development of neuronal structure and function  

UK PubMed Central (United Kingdom)

Sensory experience plays a crucial role in regulating neuronal shape and in developing synaptic contacts during brain formation. These features are required for a neuron to receive, integrate, and transmit...Full Text Available

70

Formation Energies of Antiphase Boundaries in GaAs and GaP: An ab Initio Study  

UK PubMed Central (United Kingdom)

Electronic and structural properties of antiphase boundaries in group III-V semiconductor compounds have been receiving increased attention due to the potential to integration of optically-active III-V...Full Text Available

71

Centromere-encoded RNAs are integral components of the maize kinetochore  

UK PubMed Central (United Kingdom)

RNA is involved in a variety of chromatin modification events, ranging from large-scale structural rearrangements to subtle local affects. Here, we extend the evidence for RNA–chromatin interactions...Full Text Available

2004-11-09

72

TIG of Reduced Activation Ferrite/Martensitic Steel for the Korean ITER-TBM  

International Nuclear Information System (INIS)

Test Blanket Modules (TBM) will be tested in ITER to verify the capability of tritium breeding and recovery and the extraction of thermal energy suitable for the production of electricity. A Helium Cooled Solid Breeder (HCSB) TBM has been developed in Korea to accomplish these goals. Reduced Activation Ferritic/Martensitic (RAFM) steel has been chosen as the primary candidate structural material for Korean TBM. Due to the complexity of the First wall (FW) and Side wall (SW), it is necessary to develop various joining technologies, such as Hot Isostatic Pressing (HIP), Electron Beam Welding (EBW) and Tungsten Inert Gas (TIG) welding, for the successful fabrication of TBM. In this study, the mechanical properties of TIG welded RAFM steel were investigated. Various mechanical tests of TIG-welded RAFM steel were performed to obtain the optimized TIG welding process for RAFM steel

2010-10-01

73

Secondary electron yield measurements from thin surface coatings for NLC electron cloud reduction  

CERN Document Server

In the beam pipe of the positron damping ring of the Next Linear Collider, electrons will be created by beam interaction with the surrounding vacuum chamber wall and give rise to an electron cloud. Several solutions are possible for avoiding the electron cloud, without changing the bunch structure or the diameter of the vacuum chamber. Some of the currently available solutions for preventing this spurious electron load include reducing residual gas ionization by the beam, minimizing beam photon-induced electron production, and lowering the secondary electron yield (SEY) of the chamber wall. We will report on recent SEY measurements performed at SLAC on TiN coatings and TiZrV non-evaporable getter thin films.

2004-01-01

74

Experimental investigation of wall static pressure fluctuations in parallel boiling flow  

International Nuclear Information System (INIS)

Measurements of the statistical characteristics of channel wall static pressure fluctuations in parallel one-component boiling flow are reported. The measurements span a wide range of local subcooling and vapor volume fraction, and correspond to flow regimes ranging from highly subcooled bubbly to saturated slug-annular. Vapor volume fraction measurements at the pressure measurement station are also reported in conjunction with visual observation of the flow structure. Variation of static pressure fluctuation intensity and spectral content with local thermal-hydraulic condition is demonstrated. Finally, it is suggested that diagnosis of local two-phase flow regime on the basis of (i) statistical characteristics of the pressure data, and (ii) time trace of pressure signal, may be possible. 15 refs.

1980-01-01

75

Effective diffusion coefficient of radon in concrete, theory and method for field measurements  

International Nuclear Information System (INIS)

A linear diffusion model serves as the basis for determination of an effective radon diffusion coefficient in concrete. The coefficient was needed to later allow quantitative prediction of radon accumulation within and behind concrete walls after application of an impervious radon barrier. A resolution of certain discrepancies noted in the literature in the use of an effective diffusion coefficient to model diffusion of a radioactive gas through a porous medium is suggested. An outline of factors expected to affect the concrete physical structure and the effective diffusion coefficient of radon through it is also presented. Finally, a field method for evaluating effective radon diffusion coefficients in concrete is proposed and results of measurements performed on a concrete foundation wall are compared with similar published values of gas diffusion coefficients in concrete. (author).

76

Integration by parts: An introduction  

CERN Document Server

Integration by parts is used to reduce scalar Feynman integrals to master integrals.

2011-01-01

77

Quantization of coupled 1D vector modes in integrated photonic waveguides  

International Nuclear Information System (INIS)

A quantum mechanical analysis of the guided light in integrated photonics waveguides is presented. The analysis is made starting from one-dimensional (1D) guided vector modes by taking into account the modal orthonormalization property on a cross section of an optical waveguide, the vector structure of the guided optical modes and the reversal-time symmetry in order to quantize the 1D vector modes and to derive the quantum momentum operator and the Heisenberg equations. The results provide a quantum-consistent formulation of the linear and nonlinear quantum light propagations as a function of forward and backward creation and annihilation operators in integrated photonics. As an illustration, an application to an integrated nonlinear directional coupler is given, that is, both the nonlinear momentum and the Heisenberg equations of the nonlinear coupler are derived.

2008-06-01

78

U.S. Contribution 1994 Summary Report Task T12: Compatibility and irradiation testing of vanadium alloys  

Energy Technology Data Exchange (ETDEWEB)

Vanadium alloys exhibit important advantages as a candidate structural material for fusion first wall/blanket applications. These advantages include fabricability, favorable safety and environmental features, high temperature and high wall load capability, and long lifetime under irradiation. Vanadium alloys with (3-5)% chromium and (3-5)% titanium appear to offer the best combination of properties for first wall/blanket applications. A V-4Cr-4Ti alloy is recommended as the reference composition for the ITER application. This report provides a summary of the R&D conducted during 1994 in support of the ITER Engineering Design Activity. Progress is reported for Vanadium Alloy Production, Welding, Physical Properties, Baseline Mechanical Properties, Corrosion/Compatibility, Neutron Irradiation Effects, Helium Transmutation Effects on Irradiated Alloys, and the Status of Irradiation Experiments. ...

1995-03-01

79

Progress on fatigue characterization of ITER primary first wall mock-ups  

International Nuclear Information System (INIS)

In 2001, EFDA has assigned to ENEA a contract for the thermomechanical testing of six mock-ups of the ITER primary wall module. These small scale mock-ups, reproducing representative portions of the reference ITER primary wall panels, were fabricated during ITER EDA phase by solid hot isostatic pressing (HIPping) of an AISI 316L stainless steel back structure to a alumina dispersion strengthened (DS)-Cu alloy heat sink armored with beryllium tiles. The experimental program, carried-out at ENEA Brasimone CEF 1-2 thermal hydraulic facility, was focused on the thermal mechanical testing of these mock-ups aiming at verifying which tile geometry and manufacturing procedure assures the required reliability of the beryllium/DS-Cu alloy/SS joints at high incident heat flux (>0.8 MW/m"2) both at steady state and under thermal fatigue tests. The paper presents the progress in the experimental activity of the first test campaign ...

2003-09-01

80

GDH pipe break transient analysis of the RBMK - 1500.  

Energy Technology Data Exchange (ETDEWEB)

Presented in this paper is the transient analysis of a Group Distribution Header (GDH) following a guillotine break at the end of the header. The GDH is the most important component of reactor safety in case of accidents. Emergency Core Cooling System (ECCS) piping is connected to the GDH piping such that, during an accident, coolant passes from the GDH into the ECCS. The GDH that is propelled into motion after a guillotine break can impact neighboring GDH pipes or the nearest wall of the compartment. The cases of GDH impact on an adjacent GDH and its attached piping are investigated in this paper. A whipping RBMK-1500 GDH along with neighboring concrete walls and pipelines is modeled using finite elements. The finite element code NEPTUNE used in this study enables a dynamic pipe whip structural analysis that accommodates large displacements and nonlinear material characteristics. The results of the study indicate that a ...

2002-05-15

81

Conceptual design of main coolant pump for integral reactor SMART  

Energy Technology Data Exchange (ETDEWEB)

The conceptual design for MCP to be installed in the integral reactor SMART was carried out. Canned motor pump was adopted in the conceptual design of MCP. Three-dimensional modeling was performed to visualize the conceptual design of the MCP and to check interferences between the parts. The theoretical design procedure for the impeller was developed. The procedures for the flow field and structural analysis of impeller was also developed to assess the design validity and to verify its structural integrity. A computer program to analyze the dynamic characteristics of the rotor shaft of MCP was developed. The rotational speed sensor was designed and its performance test was conducted to verify the possibility of operation. A prototypes of the canned motor was manufactured and tested to confirm the validity of the design concept. The MCP design concept was also investigated for fabricability by ...

1999-12-01

82

Structure and Crystallization Behavior of Nylong 66/Multi-Walled Carbon Nanotube Nanocomposites at Low Carbon Nanotube Contents  

Energy Technology Data Exchange (ETDEWEB)

Multi-walled carbon nanotubes (MWNTs) were modified with poly(hexamethylene adipamide) (also known as Nylon 66) via a controlled polymer solution crystallization method. A 'nanohybrid shish kebab' (NHSK) structure was found wherein the MWNT resembled the shish while Nylon 66 lamellar crystals formed the kebabs. These Nylon 66-functionalized MWNTs were used as precursors to prepare polymer/MWNT nanocomposites. Excellent dispersion was revealed by optical and electron microscopies. Nitric acid etching of the nanocomposites showed that MWNT formed a robust network in Nylon 66. Non-isothermal DSC results showed multiple melting peaks, which can be attributed to lamellar thickness changes upon heating. The crystallite sizes L{sub 100} and L{sup 010} of Nylon 66, determined by WAXD, decreased with increasing MWNT contents. Isothermal DSC results showed that crystallization kinetics increased first and then decreased with increasing ...

2007-01-01

83

Pressure and impulse scaling methods for wall impact in ICF (inertial confinement fusion)  

Energy Technology Data Exchange (ETDEWEB)

The design of the first structural wall (FSW) in an inertial confinement fusion (ICF) reactor requires some knowledge of the expected wall loading produced by x-ray and neutron deposition; specifically in the High Yield Lithium Injection Fusion Energy (HYLIFE) reactor, wall loading results from two sources -- gas shock and liquid impact. Gas shock is derived from x-ray deposition in the thin layers of exposed blanket material, producing ionized vapor, which will generate gas shock on the FSW. Liquid impact, on the other hand, results from the acceleration of liquid blanket material by two possible forces -- the drag from vapor expansion through the blanket material and the neutron-induced isochoric disassembly process. Both impacts, however, are coupled by the interaction of hot gas expanding through the liquid blanket. This paper discusses scaling methods for estimating pressure and impulse on the ...

1990-01-01

84

An ecologically relevant exposure assessment for a polluted river using an integrated multivariate PLS approach  

International Nuclear Information System (INIS)

A case study is presented where an integrated, ecologically relevant exposure assessment is presented for a polluted lowland river. Using partial least squares regression of latent structures (PLS), an analysis of the impact of two effluents on physico-chemical water quality measures, macroinvertebrate and diatom communities, and in situ bioassay responses with four different test species are combined into an integrative exposure assessment. Bioassays focussed on growth and condition related endpoints, because they are key functional processes of organisms and populations. Integrating these multiple lines of evidence, we were able to discriminate among the impact of both effluents, link changes in physico-chemical water quality with bioassay endpoints and ecological quality of the ecosystem, and address the importance of integrating all information into one exposure assessment ...

2004-11-01

85

Some geotechnical aspects of the Hyogo-ken Nanbu (Kobe) earthquake of January 17, 1995  

Energy Technology Data Exchange (ETDEWEB)

A geological and geotechnical framework was provided in order to facilitate understanding of the damage to structures resulting from soil conditions during the earthquake of January 17, 1995 at Hyogo-ken Nanbu (Kobe), Japan. Special attention was paid to the large scale failures of the quay walls in the port of Kobe, resulting from liquefaction. The performance of structures in improved and unimproved ground were compared. It was observed that locations with some previous site improvements through densification behaved satisfactorily, despite unanticipated high levels of ground motion. Soil-structure interaction problems, such as pile foundations, bridge piers, lifelines, and an underground subway station were also described. Reference was made to the significance of these failures for the seismic design in the Fraser Delta in British Columbia in view of the area`s proneness to liquefaction during a ...

1996-06-01

86

Chamber technology concepts for inertial fusion energy: Three recent examples  

Energy Technology Data Exchange (ETDEWEB)

The most serious challenges in the design of chambers for inertial fusion energy (IFE) are 1) protecting the first wall from fusion energy pulses on the order of several hundred megajoules released in the form of x rays, target debris, and high energy neutrons, and 2) operating the chamber at a pulse repetition rate of 5-10 Hz (i.e., re-establishing, the wall protection and chamber conditions needed for beam propagation to the target between pulses). In meeting these challenges, designers have capitalized on the ability to separate the fusion burn physics from the geometry and environment of the fusion chamber. Most recent conceptual designs use gases or flowing liquids inside the chamber. Thin liquid layers of molten salt or metal and low pressure, high-Z gases can protect the first wall from x rays and target debris, while thick liquid layers have the added benefit of protecting structures from fusion ...

1997-02-27

87

The Structure of Reciprocity  

Science.gov (United States)

Reciprocity is one of the defining features of social exchange and social life, yet exchange theorists have tended to take it for granted. Drawing on work from a decade-long theoretical research program, I argue that reciprocity is structured and variable across different forms of exchange, that these variations in the structure of reciprocity have profound effects on the emergence of integrative bonds of trust and solidarity, and that these effects are explained and mediated by a set of risk- and conflict-based processes. I discuss the consequences of this work for organizational theories of embeddedness and the production of social capital through network ties. Finally, I ask how the structure of networks and the structure of reciprocity are related to one another, and explore possible implications of the structure of reciprocity for exchange theorists' ...

2009-12-01

88

Seismic analysis of the Par Pond Dam: Study of slope failure and liquefaction. Technical evaluation report  

Energy Technology Data Exchange (ETDEWEB)

Stability concerns of the Par Pond Dam, an embankment structure in the Savannah River Site complex, resulted in a comprehensive evaluation of the state of its integrity. Specifically, excessive seepage through the embankment, slope failure due to an earthquake event as well as liquefaction potential of the embankment and the foundation are addressed and the potential of failure is evaluated. Lastly, remedial benefits of the addition of a berm structure are also assessed.

1994-07-01

89

Heat exchange enhancement structure  

Energy Technology Data Exchange (ETDEWEB)

A passive heat exchange enhancement structure which operates by free convection includes a flat mounting portion having a plurality of integral fins bent outwardly from one side edge thereof. The mounting portion is securable around a stovepipe, to a flat surface or the like for transferring heat from the pipe through the fins to the surrounding air by rotation-enhanced free convection.

1980-12-02

90

Safety philosophy and concepts for large liquid metal breeder reactor power plants  

International Nuclear Information System (INIS)

This paper addresses the unique related aspects of the LMFBR concept which are of significance to containment design and structural analysis. Topics covered include: Primary boundary integrity assurance; Effects of sodium spills on integrity of structures; Provisions being considered for containment of melted cores; Fuel handling accidents. Specific reference is made to the FFTF and the Clinch River Breeder Reactor Project designs and methods of treatment of the above problems. In particular, the part played by tests, such as those carried out on a simulated FFTF model, and the planned structural reliability and related programs are considered. Where practicable, these topics are addressed in a manner which places FFTF and CRBR in context with other LMFBR's and point to a possible direction for future American LMFBR designs. (Auth.).

91

Safety philosophy and concepts for large liquid metal breeder reactor power plants  

International Nuclear Information System (INIS)

This paper will adress the unique safety related aspects of the LMFBR concept which are of significance to containment design and structural analyses. Topics to be covered will include: primary boundary integrity assurance; effects of sodium spills on integrity of structures; provisions being considered for containment of melted cores; and fuel handling accidents. Specific reference will be made to the FFTF and the Clinch River Breeder Reactor Project designs and methods of treatment of the above problems. In particular, the part played by tests, such as those carried out on a simulated FFTF model, and the planned structural reliability and related programs will be considered. Where practicable, these topics will be addressed in a manner which places FFTF and CRBR in context with other LMFBR's, and will point to a possible direction for future American LMFBR designs.

1975-09-01

92

Applicability of chemical cleaning process to steam generator secondary side, (4). Comprehensive applicability evaluation of chemical cleaning and its effect on integrity of other structural materials other than steam generator tubes  

International Nuclear Information System (INIS)

The application of chemical cleaning for dissolving and removing scale and sludge is being planned in the Japanese pressurized water reactor (PWR) plant in order to maintain high heat transfer performance and to prevent steam generator (SG) tube degradation. In this paper, the effectiveness of the Electric Power Research Institute (EPRI) and German Kraftwerk Union (KWU) processes on the integrity of structural materials other than SG tubes and the comprehensive applicability of chemical cleaning are discussed. The integrity of structural materials such as carbon steel, low-alloy steel and stainless steel was maintained after the EPRI and KWU processes. KWU chemical cleaning tailored for crevice cleaning has been studied to improve its cleaning effectiveness in crevices and to control the corrosion depth of structural materials less than the criterion for corrosion depth. (author)

2006-11-01

93

On the long term indoor radon concentration measurements the basement of Japanese hospitals  

International Nuclear Information System (INIS)

Long term indoor radon gas measurements using a passive monitor were conducted in the basement rooms of five hospitals, which are built in the Tokyo metropolitan area. The ventilation rate averaged over all hospital was 12.3 air change per hour (ACH). The highest radon concentration was 56.3 Bq/m"3. The value averaged concentration over all hospital and all season was 20 Bq/m"3. But the average of the two hospitals were twice as high as those of three others. Since the total ventilation rate integrated over a day is not different much, the reason of the concentration difference is considered to be the difference in radon emission rate from concrete wall and soil of the each hospital. Though we inquired workers about 'Environmental complaints', it do not show the direct relation between radon and environmental complaints. (author)

94

Materials and Components Technology Division research summary, 1992  

Energy Technology Data Exchange (ETDEWEB)

The Materials and Components Technology Division (MCT) provides a research and development capability for the design, fabrication, and testing of high-reliability materials, components, and instrumentation. Current divisional programs related to nuclear energy support the development of the Integral Fast Reactor (IFR): life extension and accident analyses for light water reactors (LWRs); fuels development for research and test reactors; fusion reactor first-wall and blanket technology; and safe shipment of hazardous materials. MCT Conservation and Renewables programs include major efforts in high-temperature superconductivity, tribology, nondestructive evaluation (NDE), and thermal sciences. Fossil Energy Programs in MCT include materials development, NDE technology, and Instrumentation design. The division also has a complementary instrumentation effort in support of Arms Control Technology. Individual abstracts have been prepared for the ...

1992-11-01

95

Study of structural, thermodynamical and dynamical properties of molecular liquids confined in nano-porous materials  

International Nuclear Information System (INIS)

When liquids are confined in nano-scopic dimensions, their properties differ from the corresponding bulk liquid, due to their reduced dimensionality and surface effects. Phase transition temperatures and pressures are often shifted from the bulk values and new phases can appear due to the strong interactions of the molecules with the confining walls. We have studied the structural and dynamical properties of aromatic liquids such as benzene, toluene, and ortho-terphenyl confined in nano-porous materials, MCM-41 and SBA-15, synthesized and characterized in our laboratory. A non-trivial dependence of the glass transition temperature, Tg, on the pore size and surface treatment of nano-porous materials is confirmed and interpreted as resulting from a competition between the fluid-wall and fluid-fluid intermolecular interactions. An increase of Tg is observed for small pore sizes and attractive surface while Tg decreases for non ...

2006-01-01

96

Topological Defects in the Moduli Sector of String Theory  

CERN Document Server

We point out that the moduli sector of the $(2,2)$ string compactification with its nonperturbatively preserved non-compact symmetries is a fertile framework to study global topological defects, thus providing a natural source for the large scale structure formation. Based on the target space modular invariance of the nonperturbative superpotential of the four-dimensional N=1 supersymmetric string vacua, topologically stable stringy domain walls are found. They are supersymmetric solutions, thus saturating the Bogomolnyi bound. It is also shown that there are moduli sectors that allow for the global monopole-type and texture-type configurations whose radial stability is ensured by higher derivative terms.

1991-01-01

97

Structural and magnetic studies on the enhancement of the giant magnetoimpedance by ion irradiation  

British Library Electronic Table of Contents (United Kingdom)

The mechanism of abrupt increase of the giant magneto impedance (GMI) ratio in the ion irradiated Co-based amorphous ribbon has been investigated. The grazing incident X-ray diffraction and transmission electron microscope were used to characterize the samples before and after ion irradiation. The GMI-ratio considerably increased in the ion irradiated samples and the GMI response showed strong dependence on the driving frequencies. The Barkhausen noise (BN) signals are increased for the Ar ion irradiated sample with dose of 1x10^1^7 ion/cm^2. The results are interpreted in terms of GMI variation associated with domain wall dynamics.

2011-01-01

98

Regenerative zinc/air and zinc/ferricyanide batteries for stationary power applications  

Energy Technology Data Exchange (ETDEWEB)

The authors report a novel configuration for a zinc-particle, packed-bed anode in which an open structure of high hydraulic permeability is maintained indefinitely in a cell with closely spaced walls by the formation of particle bridges and associated gaps. The configuration minimizes electrolyte pumping costs, allows rapid refueling and partial recharge, and provides for 100% zinc consumption. This approach benefits zinc/air fuel batteries by allowing nearly continuous operation and fuel recycle without commercial infrastructure; it benefits Zn/[Fe(CN){sub 6}]{sup {minus}3} batteries by eliminating shape-change and polarization problems found with planar anodes.

1994-05-01

99

Mixed convection flow in a horizontal rectangular channel subjected to a horizontal thermal gradient  

British Library Electronic Table of Contents (United Kingdom)

This paper deals with a mixed convection water flow in a horizontal rectangular duct, uniformly heated from one lateral vertical wall and thermally insulated elsewhere. The supplied heat flux induces a secondary flow, which structure is constituted of one longitudinal roll in the considered aspect ratio (??=?1.9), embedded into a return flow of possibly large stream wise extension (up to twenty channel heights). Such situation induces helicoidal trajectories for the fluid flow particles, which contributes to a heat transfer enhancement compared to purely forced convection flow.

2011-01-01

100

Mixed convection flow in a horizontal rectangular channel subjected to a horizontal thermal gradient  

Science.gov (United States)

This paper deals with a mixed convection water flow in a horizontal rectangular duct, uniformly heated from one lateral vertical wall and thermally insulated elsewhere. The supplied heat flux induces a secondary flow, which structure is constituted of one longitudinal roll in the considered aspect ratio (? = 1.9), embedded into a return flow of possibly large stream wise extension (up to twenty channel heights). Such situation induces helicoidal trajectories for the fluid flow particles, which contributes to a heat transfer enhancement compared to purely forced convection flow.

2011-04-01

101

Development of conductive nanotemplates on ZnSe  

International Nuclear Information System (INIS)

We demonstrate the possibility to fabricate arrays of pores oriented perpendicular and parallel to the top surface of the ZnSe nanotemplate. The control of material conductivity allows one to produce porous ZnSe samples with the mean pore diameter and characteristic skeleton wall thickness from several hundreds of nanometers to about 15 nm. In addition, electrochemical treatment of ZnSe single crystals using photoresist masks allows one to prepare buried porous structures with pores directed parallel to the top template surface, which is especially important for photonic applications.

2011-07-07

102

Ideal Magnetohydrodynamics Stability Spectrum with a Resistive Wall  

Energy Technology Data Exchange (ETDEWEB)

We show that the eigenvalue equations describing a cylindrical ideal magnetophydrodynamicsw (MHD) plasma interacting with a thin resistive wall can be put into the standard mathematical form: ??? = ??? ?. This is accomplished by using a finite element basis for the plasma, and by adding an extra degree of freedom corresponding to the electrical current in the thin wall. The standard form allows the use of linear eigenvalue solvers, without additional interations, to compute the complete spectrum of plasma modes in the presence of a surrounding restrictive wall at arbitrary separation. We show that our method recovers standard results in the limits of (1) an infinitely resistive wall (no wall), and (2) a zero resistance wall (ideal wall).

2008-05-22

103

Photovoltaic solar power in building engineering. Experience feedback in France of the European Hip Hip project. Advances and realizations; L'electricite solaire photovoltaique dans le batiment. Retour d'experience en France du Projet Europeen Hip Hip. Avancees et realisations  

Energy Technology Data Exchange (ETDEWEB)

The European demonstration project Hip Hip (house integrated photovoltaic high-tech in public) led the French photovoltaic market to reach a level comparable to those of the other European countries in terms of relevance of implemented solutions and costs. This document presents the best realizations and the experience gained through the Hip Hip project. Its aim is to convince the designers and managers of building projects of the advantages of photovoltaic installations integrated to the structure and connected to the power distribution grid: 1 - presentation of the technology; 2 - status of the Hip Hip demonstration project (goals, results: main innovations and impact on the French market); 3 - different possibilities of integration to the building structure; 4 - examples of projects realized in France in the framework of the Hip Hip project: integration in ...

2003-07-01

104

Free-field representation of the quantum affine algebra U_q(sl_2) and form factors in the higher-spin XXZ model  

International Nuclear Information System (INIS)

We consider the spin-k/2 XXZ model in the antiferromagnetic regime using the free-field realization of the quantum affine algebra U_q(sl_2) of level k. We give a free-field realization of the type-II q-vertex operator, which describes creation and annihilation of physical particles in the model. By taking a trace of the type-I and type-II q-vertex operators over the irreducible highest-weight representation of U_q(sl_2), we also derive an integral formula for form factors in this model. Investigating the structure of poles, we obtain a residue formula for form factors, which is a lattice analog of the higher-spin extension of Smirnov's formula in the massive integrable quantum field theory. This result as well as the quantum deformation of the Knizhnik-Zamolodchikov equation for form factors shows a deep connection in the mathematical structure of the integrable lattice models and ...

1994-12-01

105

Evaluation of structural integrity of crossover leg piping system with dynamic whip restraints  

Energy Technology Data Exchange (ETDEWEB)

Interference between the crossover leg of the Reactor Coolant System(RCS) and the Pipe Whip Restraints(PWR) has brought a degradation issue of the integrity of the Reactor Coolant System in Westinghouse type Nuclear Power Plants(NPPs) of Korea. According to the gap inspection carried out during planned overhaul (year 2000), interference between the crossover leg and the PWR was found in each RCS loop. This plant has had the high vibration problem on the RC pump 'B'. The reason for the high vibration in the RC pump 'B' had been massively surveyed and it was found that the crossover leg of RCS contacted with the PWR in hot condition. Since the contact between the crossover leg and the PWR changes the dynamic characteristics of the piping system for the RCS, this is considered as one reason for the high vibration. And a possibility of overstress on the crossover leg due to the contact with the PWR should be evaluated. Through ...

2001-07-01

106

FFTF [Fast Flux Test Facility] Integrated Leak Rate Test Computer System  

International Nuclear Information System (INIS)

The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled test reactor located on the Hanford Site. The FFTF is the only reactor of this type designed and operated with the intent of meeting the licensing requirements of the Nuclear Regulatory Commission (NRC). Unique characteristics of the FFTF that present special challenges related to leak rate testing include thin wall containment vessel construction, cover gas systems that penetrate containment, and a low-pressure design basis accident. The successful completion in 1986 of the third FFTF Integrated Leak Rate Test (ILRT) five days ahead of schedule and 10% under budget was a major achievement for the Westinghouse Hanford Company. The success of this operational safety test was due in large part to a special local area network (LAN) of three IBM PC/XT computers that monitored the sensor data, calculated the containment vessel leak rate, and displayed test results. The multiple computer ...

107

Correlation between designed wall thickness of gas pipelines and external and internal corrosion processes; Adequacao de espessura de parede projetada em funcao de processos de corrosao externa e interna em gasodutos  

Energy Technology Data Exchange (ETDEWEB)

Corrosion control on gas pipelines plays an important role on the assessment of pipeline integrity and reliability. In many countries a great extension of buried pipelines is used on transport and distribution systems. This extension will be certainly increased in a near future due to the increasing consumption of natural gas. Inadequate corrosion control can drive to pipeline failures, bringing up the possibility of accidents in populated or environmental protected areas, bringing together severe economical, legal and environmental consequences. Corrosion is frequently considered as a natural and inevitable phenomenon. Based upon this assumption, some recommendations are included on design standards of gas pipelines in order to compensate its detrimental effect. The aim of this work is to present a review of the correlation between external corrosion process and the guidelines established during the project phase of gas pipelines. It is intended to contribute for ...

2004-07-01

108

Spin-resolved magnetic studies of focused ion beam etched nano-sized magnetic structures  

International Nuclear Information System (INIS)

Scanning ion microscopy with polarization analysis (SIMPA) is used to study the spin-resolved surface magnetic structure of nano-sized magnetic systems. SIMPA is utilized for in situ topographic and spin-resolved magnetic domain imaging as well as for focused ion beam (FIB) etching of desired structures in magnetic or non-magnetic systems. Ultra-thin Co films are deposited on surfaces of Si(1 0 0) substrates, and ultra-thin, tri-layered, bct Fe(1 0 0)/Mn/bct Fe(1 0 0) wedged magnetic structures are deposited on fcc Pd(1 0 0) substrates. SIMPA experiments clearly show that ion-induced electrons emitted from magnetic surfaces exhibit non-zero electron spin polarization (ESP), whereas electrons emitted from non-magnetic surfaces such as Si and Pd exhibit zero ESP, which can be used to calibrate sputtering rates in situ. We report on new, spin-resolved magnetic microstructures, such as magnetic 'C' states and magnetic vortices, ...

2005-04-01

109

Breaking the Biological barriers to Cellulosic Ethanol: A Joint Research Agenda  

Energy Technology Data Exchange (ETDEWEB)

A robust fusion of the agricultural, industrial biotechnology, and energy industries can create a new strategic national capability for energy independence and climate protection. In his State of the Union Address (Bush 2006), President George W. Bush outlined the Advanced Energy Initiative, which seeks to reduce our national dependence on imported oil by accelerating the development of domestic, renewable alternatives to gasoline and diesel fuels. The president has set a national goal of developing cleaner, cheaper, and more reliable alternative energy sources to substantially replace oil imports in the coming years. Fuels derived from cellulosic biomass - the fibrous, woody, and generally inedible portions of plant matter - offer one such alternative to conventional energy sources that can dramatically impact national economic growth, national energy security, and environmental goals. Cellulosic biomass is an attractive energy feedstock because it is an abundant, domestic, renewable ...

2006-06-01

110

Nondestructive Technique Survey for Assessing Integrity of Composite Firing Vessel  

Energy Technology Data Exchange (ETDEWEB)

The repeated use and limited lifetime of a composite tiring vessel compel a need to survey techniques for monitoring the structural integrity of the vessel in order to determine when it should be retired. Various nondestructive techniques were researched and evaluated based on their applicability to the vessel. The methods were visual inspection, liquid penetrant testing, magnetic particle testing, surface mounted strain gauges, thermal inspection, acoustic emission, ultrasonic testing, radiography, eddy current testing, and embedded fiber optic sensors. It was determined that embedded fiber optic sensor is the most promising technique due to their ability to be embedded within layers of composites and their immunity to electromagnetic interference.

2000-08-01

111

Education with ICT in South Korea and Chile  

British Library Electronic Table of Contents (United Kingdom)

This article presents a linear-analytical case study on the development of ICT within the educational systems of Chile and South Korea. Through a comprehensive meta-data analysis and bibliographic review, we collected information on both educational systems and their ICT adoption policies. Key differences necessary to understand how both countries have developed their educational systems by integrating ICT were analyzed, including the educational system structure, the organization of state entities responsible for educational ICT, cultural characteristics, the creation of policies regarding ICT in education, and the effectiveness of such policies for the expansion of infrastructure and the ICT curriculum integration. We analyze these key differences in order to understand two cases of ICT ...

2011-01-01

112

Integrating mission and strategy for nonprofit organizations  

CERN Document Server

Integrating mission and strategy for nonprofit organizations

2005-01-01

113

FFTF criteria for run-to-cladding-breach experiments  

International Nuclear Information System (INIS)

The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled fast reactor, which is designed to test a variety of different structural and fuel materials. A safety analysis is performed for each experiment that is irradiated in FFTF. The FFTF final safety analysis report (FSAR) assumed that all driver fuel assemblies would maintain cladding integrity during normal operations and all design transients. Maintenance of cladding integrity retains three barriers to any fission gas release to the public and also prevents any potential contact between the fuel and coolant. Experiments are, in general, expected to meet the same criterion. Selected experiments can, however, be classified as run-to-cladding-breach experiments (RTCB). The purpose of this paper is to describe alternative acceptance criteria for RTCB experiments that they feel provide protection equivalent to the maintenance of cladding integrity.

1986-06-15

114

Combined migration velocity model-building and its application in tunnel seismic prediction  

Science.gov (United States)

We propose a combined migration velocity analysis and imaging method based on Kirchhoff integral migration and reverse time migration, using the residual curvature analysis and layer stripping strategy to build the velocity model. This method improves the image resolution of Kirchhoff integral migration and reduces the computations of the reverse time migration. It combines the advantages of efficiency and accuracy of the two migration methods. Its application in tunnel seismic prediction shows good results. Numerical experiments show that the imaging results of reverse time migration are better than the imaging results of Kirchhoff integral migration in many aspects of tunnel prediction. Field data show that this method has efficient computations and can establish a reasonable velocity model and a high quality imaging section. Combination with geological information can make an accurate prediction of the front of the ...

2010-09-01

115

Algebraic Principles of Quantum Field Theory II: Quantum Coordinates and WDVV Equation  

CERN Document Server

This paper is about algebro-geometrical structures on a moduli space $\\CM$ of anomaly-free BV QFTs with finite number of inequivalent observables or in a finite superselection sector. We show that $\\CM$ has the structure of F-manifold -- a linear pencil of torsion-free flat connection with unity on the tangent space, in quantum coordinates. We study the notion of quantum coordinates for the family of QFTs, which determines the connection 1-form as well as every quantum correlation function of the family in terms of the 1-point functions of the initial theory. We then define free energy for an unital BV QFT and show that it is another avatar of morphism of QFT algebra. These results are consequences of the solvability of refined quantum master equation of the theory. We also introduce the notion of a QFT integral and study some properties of BV QFT equipped with a QFT integral. We show that BV QFT with ...

2011-01-01

116

Technology  

Indian Academy of Sciences (India)

integration with available technology and initiatives ...

117

Helium-cooling in fusion power plants  

Energy Technology Data Exchange (ETDEWEB)

This paper reviews different helium-cooled first wall and blanket designs; and compares the selection of structural materials. The authors found that the solid breeder, SiC-composite material option generates the lowest amount of induced radioactivity and afterheat and has the highest temperature capability. When combined with the direct cycle gas turbine system, it has the potential to be the most economical fusion system and can compete with advanced fission reactors. When compared to martensitic steel and V-alloy, SiC-composite is the least developed of these three structural materials, a focused development effort will be needed. Fundamental research has begun in addressing the issues of optimized composite materials, irradiation effects, leak tightness and low activation braze materials. Development of helium-cooled high heat flux components and further development of the direct cycle gas turbine system will also be ...

1994-11-01

118

Characterization of radon penetration of different structural domains of concrete. Final project report  

International Nuclear Information System (INIS)

This report documents the research activities by Rogers and Associates Engineering Corporation on grant DE-FG03-93ER61600 during the funded project period from August 1993 to April 1996. The objective of this research was to characterize the mechanisms and rates of radon gas penetration of the different structural domains of the concrete components of residential floor slabs, walls, and associated joints and penetrations. The research was also to characterize the physical properties of the concretes in these domains to relate their radon resistance to their physical properties. These objectives support the broader goal of characterizing which, if any, concrete domains and associated properties constitute robust barriers to radon and which permit radon entry, either inherently or in ways that could be remediated or avoided.

119

On the integration of technology readiness levels at Sandia National Laboratories.  

Energy Technology Data Exchange (ETDEWEB)

Integrating technology readiness levels (TRL) into the management of engineering projects is critical to the mitigation of risk and improved customer/supplier communications. TRLs provide a common framework and language with which consistent comparisons of different technologies and approaches can be made. At Sandia National Laboratories, where technologies are developed, integrated and deployed into high consequence systems, the use of TRLs may be transformational. They are technology independent and span the full range of technology development including scientific and applied research, identification of customer requirements, modeling and simulation, identification of environments, testing and integration. With this report, we provide a reference set of definitions for TRLs and a brief history of TRLs at Sandia National Laboratories. We then propose and describe two approaches that may be used to ...

2006-09-01

120

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-12-31

121

Structure of Mesita del Buey at TA-54, Los Alamos National Laboratory, New Mexico  

Energy Technology Data Exchange (ETDEWEB)

The geological structure of Mesita del Buey at Technical Area 54 (TA-54) was examined using precise surveying of the contact between units 1v and 2 of the Tshirege Member of the Bandelier Tuff at 3.5 km along the north wall of Pajarito Canyon and 0.6 km along the north wall of a tributary to Canada del Buey. Estimated structure contours on this contact indicate typical strikes of N40E to N70E along this part of Mesita del Buey, although the apparent strike of the tuff is E-W at the western part of the survey. Typical dips are 1.0{degree} to 2.0{degree} to the east or southeast, with an estimated maximum dip of 3.2{degree} near the west end of Material Disposal Area G. Thirty seven faults with vertical displacements of 5 to 65 cm were observed in outcrop along the Pajarito Canyon traverse, and, due to the incomplete exposure of the unit 1v-unit 2 contact, many more faults of this magnitude undoubtedly ...

1998-04-23

122

Development of MHD generator channel walls, 1  

International Nuclear Information System (INIS)

Experimental results of compatibility tests on ceramics-metal bonded structures performed under high heat flux conditions in splash test apparatus are reported. Emphasis is placed on results of the channel wall design and its critical operating conditions under MHD environment. The module design of one cold type and three semihot type insulators have been tested. These materials were Al_2O_3, Al_2MgO_4, LaAlO_4, MgO and Sialon ceramics. The methods of cold type ceramics-metal bonding structure were studied on Al_2O_3 and Spinel spray coating technology. The refractory metallizing and ceramics-metal graded structure manufactured by HIP technologies were applied to bonding between the MgO or LaAlO_4 and metallic cooling system. The Sialon non-bonding structure was tested with mechanical supported cooling system by shrinc fitting method. The results indicated that the bonding ...

123

Effect of water chemistry improvement on flow accelerated corrosion in light-water nuclear reactor  

International Nuclear Information System (INIS)

Flow Accelerated Corrosion (FAC) of Carbon Steel (CS) piping has been one of main issues in Light-Water Nuclear Reactor (LWRs). Wall thinning of CS piping due to FAC increases potential risk of pipe rupture and cost for inspection and replacement of damaged pipes. In particular, corrosion products generated by FAC of CS piping brought steam generator (SG) tube corrosion and degradation of thermal performance, when it intruded and accumulated in secondary side of PWR. To preserve SG integrity by suppressing the corrosion of CS, High-AVT chemistry (Feedwater pH9.8#+-#0.2) has been adopted to Tsuruga-2 (1160 MWe PWR, commercial operation in 1987) in July 2005 instead of conventional Low-AVT chemistry (Feedwater pH 9.3). By the High-AVT adoption, the accumulation rate of iron in SG was reduced to one-quarter of that under conventional Low-AVT. As a result, a tendency to degradation of the SG thermal efficiency was improved. On the other hand, it ...

2009-10-01

124

Neural integrated control for a free-floating space robot with suddenly changing parameters  

British Library Electronic Table of Contents (United Kingdom)

Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system, this paper proposes a control strategy based on a variable structure neural integrated controller. This scheme does not need a precise space robot model, making use of the radial basis function neural network ability approach to learn about an uncertain model. The network weights are adjusted online in real-time. During the early period of the control phase and parameter changes, the variable structure controller compensates for the uncertain model which the neural network could not learn well. It also creates global asymptotic stability for the whole closed-loop system. Simulation results show that the controller can handle bad changea...

2011-01-01

125

Preparation of Permalloy nanostructures using focused ion beam methods  

International Nuclear Information System (INIS)

Focused ion beam (FIB) milling is a powerful and versatile tool for the maskless fabrication of structures and devices at micro- and nanometer scales. The approach is based on the milling and deposition capabilities of a focused ion beam, where the latter is achieved by ion-beam-assisted decomposition of a metalorganic gas precursor of the specific material that has to be deposited. The combination of FIB and scanning electron microscopy in the same unit (so-called dual-beam unit) further expands the capabilities of the approach by the possibility of performing electron-beam-assisted deposition and inspection. Permalloy nanowires with electrical contacts patterned by FIB-Pt deposition were prepared in the dual-beam unit. Various types of notches to pin magnetic domain walls were additionally fabricated by means of FIB. The fabrication parameters for a structural modification of the Permalloy structures ...

2010-03-21

126

Design of Reactor Head Structure Assembly Using Axiomatic Design  

Energy Technology Data Exchange (ETDEWEB)

The Reactor Head Structure Assembly(RHSA) is the structure located on the reactor assembly. The purpose of the assembly is providing interface location for cables, preventing pipe whips, prohibiting instruments from becoming missiles, and restraining CEDMs' horizontal motion. On the RHSA, Reactor Disconnect Panels(RDP) are installed. The installation location of RDP is to be decided to minimize the geometric interface with other components. Since the neighborhood of RHSA is crowded due to many connectors and cables, it is necessary to find the good design of RHSA to make an intricate situation attenuated and the required function maintained. The geometric shape and overall configuration of RHSA are determined by axiomatic design approach. The FRs of RHSA are specified and the corresponding DPs are found to satisfy FRs in sequence. The finite element analysis is carried out based on the result of the axiomatic design to evaluate the ...

2007-07-01

127

Spectral dependence of ultrasonic attenuation for hydrided Zr-2.5%Nb Alloy  

International Nuclear Information System (INIS)

The cold-worked Zr-2.5%Nb alloy is used as material for the pressure tubes in CANDU nuclear reactors. During the service life in reactor, diffusion of hydrogen and/or deuterium in the pressure tubes wall occur. Below a certain temperature, a stable hydride of zirconium is formed, as a brittle phase which can lead to catastrophic failures. For this reason, it is very important to be able to investigate the hydrogen effect on the micro structural properties of zirconium alloys. In the present paper a non-destructive testing technique is used, known as ultrasonic spectral analysis. When an ultrasonic signal traverses a medium, the frequency components associated with the input signal are altered. By frequency analysing the reflected signals, it is possible to study and compare the material properties. The two major parameters measured in ultrasonic spectroscopy are the attenuation and the velocity of the waves. Attenuation is determined by the ...

2009-10-12

128

Polarization of electron cyclotron emission spectra in LHD  

Energy Technology Data Exchange (ETDEWEB)

Electron cyclotron emission (ECE) can be used to determine the electron temperature profile in magnetized plasmas. The complex structure of the magnetic field configuration in the Large Helical Device (LHD), which has a large shear, complicates the analysis of the ECE spectrum. In a sheared magnetic field the propagation of X and O-mode polarization through the plasma are coupled, causing mode conversion and polarization rotation. Mode scrambling is also caused by wall reflections. In this report, this mode conversion in LHD is numerically analyzed. It was found that at low density mode conversion scrambles the ECE spectra. However, at higher density (n{sub eo} > 1.0{center_dot}10{sup 19} m{sup -3}) the polarization mode is found to rotate with the sheared magnetic field, yielding only a negligible mode conversion. Wall reflections are found to depolarize the ECE spectrum. Notwithstanding the LHD magnetic ...

1999-07-01

129

Contaminant transport in fracture networks with heterogeneous rock matrices. The Picnic code  

Energy Technology Data Exchange (ETDEWEB)

In the context of safety assessment of radioactive waste repositories, complex radionuclide transport models covering key safety-relevant processes play a major role. In recent Swiss safety assessments, such as Kristallin-I, an important drawback was the limitation in geosphere modelling capability to account for geosphere heterogeneities. In marked contrast to this limitation in modelling capabilities, great effort has been put into investigating the heterogeneity of the geosphere as it impacts on hydrology. Structural geological methods have been used to look at the geometry of the flow paths on a small scale and the diffusion and sorption properties of different rock materials have been investigated. This huge amount of information could however be only partially applied in geosphere transport modelling. To make use of these investigations the 'PICNIC project' was established as a joint cooperation of PSI/Nagra and QuantiSci to provide a new ...

2001-02-01

130

Overview of advanced techniques for fabrication and testing of ITER multilayer plasma facing walls  

International Nuclear Information System (INIS)

The design of the ITER primary first wall incorporates a multi-layered structure consisting of a layer of beryllium bonded to a layer of copper alloy with embedded stainless steel tubes which in turn is bonded to a stainless steel structure. In this configuration, the stainless steel provides structural support, the copper alloy improved resistance to high heat loads, and the beryllium layer a low Z metal interface with plasma. Fabrication, testing and control of this multi-layered structure, and indeed the entire blanket shield module, calls for advanced methods. Several associations in the four home teams and their industrial partners have been involved in various fabrication and joining tasks now grouped under L4 blanket project. In this paper, an overview of the work done so far for joining stainless steel to stainless steel, stainless steel to copper alloy, copper alloy to ...

1998-09-01

131

Application of the porous media model for the LWR process components  

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

132

Nastran nonlinear dynamic transient accident analysis for FFTF reactor component  

International Nuclear Information System (INIS)

A nonlinear dynamic transient analysis merging hand calculations and the NASTRAN structural analysis computer code was conducted for a Fast Flux Test Facility in-reactor test assembly during an extremely unlikely design basis accidental event which is considered a Hypothetical Core Disruptive Accident (HCDA). The finite element modeling of the problem took advantage of NASTRAN's versatility to create loads and nonlinear elements not previously found in NASTRAN's library. The structural criteria for the test assembly to withstand an HCDA stipulates that the test assembly and its spoolpiece shall remain integral with the reactor head such that missiles are not generated.

1976-11-15

133

Interrelation between the spatial structure of unsaturated hydrocarbon molecules and heats of their adsorption  

British Library Electronic Table of Contents (United Kingdom)

The total area (s m) of Voronoi-Dirichlet polyhedron faces corresponding to all intermolecular contacts of one molecule in the structure of crystals and the total volume of pyramids (V m) built on such faces and containing the nuclei of atoms participating in intermolecular contacts in their vertices were determined for 19 unsaturated hydrocarbons. The differential molar heat of adsorption of the hydrocarbons on graphitized thermal carbon black was found to be linearly related to the s m or V m integral parameters of their Voronoi-Dirichlet polyhedra. Aromatic hydrocarbons on the one hand and saturated hydrocarbons, olefins, and acetylene on the other are characterized by different dependences because of the special shapes of their molecular Voronoi-Dirichlet polyhedra.

2008-01-01

134

Interrelation between the spatial structure of unsaturated hydrocarbon molecules and heats of their adsorption  

Science.gov (United States)

The total area ( s m) of Voronoi-Dirichlet polyhedron faces corresponding to all intermolecular contacts of one molecule in the structure of crystals and the total volume of pyramids ( V m) built on such faces and containing the nuclei of atoms participating in intermolecular contacts in their vertices were determined for 19 unsaturated hydrocarbons. The differential molar heat of adsorption of the hydrocarbons on graphitized thermal carbon black was found to be linearly related to the s m or V m integral parameters of their Voronoi-Dirichlet polyhedra. Aromatic hydrocarbons on the one hand and saturated hydrocarbons, olefins, and acetylene on the other are characterized by different dependences because of the special shapes of their molecular Voronoi-Dirichlet polyhedra.

2008-08-01

135

Field applications of a radon barrier to reduce indoor airborne progeny  

International Nuclear Information System (INIS)

The use of uranium mill tailings in the foundations of dwellings has resulted in indoor radon progeny concentrations and gamma exposures in excess of levels presently allowed for the general public. An account is given of the applications of an epoxy coating on the indoor faces of the concrete foundations of three buildings in Grand Junction, Colorado. Epoxy barriers were shown to be effective for preventing radon influx into structures. Gamma exposure rates must be analyzed to ensure that buildup behind the barrier will not introduce an unacceptable gamma exposure level. The use of a sealant is especially economical in situations where structural integrity may be jeopardized by physical removal of uranium mill tailings. (author).

136

MARS CODE MANUAL VOLUME V: Models and Correlations  

International Nuclear Information System (INIS)

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This models and correlations manual provides a complete list of detailed information of the thermal-hydraulic models used in MARS, so that this report would be very useful for the code users. The overall ...

2002-09-01

137

Use of the acoustic method for checking the quality of concrete of hydroelectric and pumped storage stations  

Energy Technology Data Exchange (ETDEWEB)

This article describes acoustic methods used in the in-service inspection of the dams and peripheral concrete structures of the Toktogul, Kurpsai, and Bratsk hydroelectric and pumped storage plants. The tests were conducted to assess the compression strength, elasticity, and tensile strength of the concretes. Comparative evaluations against drill core studies proved the acoustic methods to be sufficiently accurate in predicting aging behavior and loss of mechanical and physical integrity in the concretes.

1987-09-01

138

Status report of the 17-M VAWT program  

Energy Technology Data Exchange (ETDEWEB)

This report is directed at the commercial potential of the 17-m, 100 kW Darrieus Vertical Axis Wind Turbine (VAWT) developed under DOE funding by Sandia National laboratories (SNL) and Alcoa Laboratories. Three of the turbines have come on line over the past 14 months and long-term testing is in progress. As the first commercially adapted Darrieus turbines built by DOE, the superior cost, structural integrity, and output characteristics demonstrated by the prototypes appear particularly promising.

1981-01-01

139

Sputter coating of tantalum and tantalum compounds. (Latest citations from the Metals abstracts alloys index database). Published Search  

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations concerning the structural properties of sputtered tantalum and tantalum compounds. The preparation of thin film capacitors and resistors is described. The electrical properties of the sputtered films are also included. The influence of the substrate on the properties of the coatings is considered, including adherence of the coating to the substrate, and the effects of impurities on coating integrity. (Contains 250 citations and includes a subject term index and title list.)

1993-09-01

140

Research and Evaluation of Advanced Nondestructive Examination (NDE) Methods for Addressing the Challenges of Inspecting Cast Austenitic Stainless Steel (CASS) Piping  

Energy Technology Data Exchange (ETDEWEB)

This Conference paper is for submission to the 7th International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, in Yokohama, Japan Specifically, this paper is being presented at this Conference on May 12-14, 2009.

2009-07-01

141

Phospholamban and its Phosphorylated Form Interact Differently with Lipid Bilayers: A 31P, 2H and 13C Solid-State NMR Spectroscopic Study  

UK PubMed Central (United Kingdom)

Phospholamban (PLB) is a 52-amino acid integral membrane protein that helps to regulate the flow of Ca2+ ions in cardiac muscle cells. Recent structural studies on the PLB pentamer...Full Text Available

2006-11-07

142

Integrability and symmetric spaces  

Energy Technology Data Exchange (ETDEWEB)

It is shown that a sufficient condition for a model describing the motion of a particle on a coset space to possess a Fundamental Poisson bracket Relation, and consequently charges in involution, is that it must be a symmetric space. The conditions, a Hamiltonian, or any functions of the canonical variables, has to satisfy in order to commute with these charges, are studied. It is show that, for the case of the noncompact symmetric spaces, these conditions lead to an algebraic structure which lays an important role in the construction of conserved quantities.

1989-01-01

143

Geothermal heat-pump systems of heat supply  

International Nuclear Information System (INIS)

The data on the multilayer operation of the objects, located in the climatic conditions of the central area of Russia and equipped with the geothermal heat-pumping systems of the heat supply are presented. The results of the analytical studies on evaluating the geothermal heat-pumping systems of the heat supply integration efficiency into the structure of the energy supply system, prevailing in the country, are presented

2004-06-01

144

Downward penetration of hot UO/sub 2/ into basalt concrete  

Energy Technology Data Exchange (ETDEWEB)

Following a postulated meltdown accident, the integrity of containment building structural material under attack by hot molten core debris and the safeguard of environment against radiological releases constitutes the final line of defense in PAHR safety assessment. Such assessment requires a good knowledge of UO/sub 2//interaction and penetration with different types of concrete. The present study focuses on the phenomena associated with core debris interaction/penetration with substrate basalt concrete.

1983-01-01

145

Discrete phase retrieval in musical structures  

British Library Electronic Table of Contents (United Kingdom)

This paper describes phase-retrieval approaches in music by focusing on the particular case of the cyclic groups (beltway problem). After presenting some old and new results on phase retrieval, we introduce the extended phase retrieval for a generalized musical Z-relation. This concept is accompanied by mathematical definitions and motivations from computer-aided composition. We assume from the reader basic knowledge of groups, topological groups, group algebras, group actions, Lebesgue integration, convolution products, and Fourier transform.

2011-01-01

146

Boundary S matrices with N=2 supersymmetry  

CERN Document Server

We propose the exact boundary S matrix for breathers of the N=2 supersymmetric sine-Gordon model. We argue that this S matrix has three independent parameters, in agreement with a recently-proposed action. We also show, contrary to a previous claim, that the ``universal'' supersymmetric boundary S matrix commutes with two supersymmetry charges. General N=2 supersymmetric boundary integrable models are expected to have boundary S matrices with a similar structure.

2001-01-01

147

Architectural design for reliability  

Energy Technology Data Exchange (ETDEWEB)

Design-for-reliability concepts can be applied to the products of the construction industry, which includes buildings, bridges, transportation systems, dams, and other structures. The application of a systems approach to designing in reliability emphasizes the importance of incorporating uncertainty in the analyses, the benefits of optimization analyses, and the importance of integrating reliability, safety, and security. 4 refs., 3 figs.

1997-08-01

148

Assessing the internal mechanical integrity of power transformers using vibration tests  

Energy Technology Data Exchange (ETDEWEB)

Machine condition monitoring (MCM) has the capability to predict equipment maintenance needs which can reduce forced down-time and facilitate the avoidance of catastrophic failures and the consequential secondary damage. It can be used to allow confident deferral of routine maintenance, and improve equipment performance, availability, reliability and safety. In order to capitalize on the potential benefits of MCM directed toward power transformers two types of vibration tests were conducted on transformers owned and operated by Cargill Inc. and IES Utilities at the Bridgeport corn plant in Eddyville, Iowa. These tests involved collecting vibration signals from the transformer tank walls during transformer energization at no-load and during steady state operation at various loads. These vibration signals were then used to detect deterioration of internal mechanical integrity. Both types of tests conducted on the transformers at the Eddyville ...

1996-12-31

149

Analytical study on integrity of BWR reactor internal structures against water hammer under RIA conditions  

Energy Technology Data Exchange (ETDEWEB)

The integrity of the RPV head and reactor internals was assessed by means of fluid-structural analyses using a coupled method to evaluate the water hammer phenomenon arising from high burnup fuel failure under RIA conditions. The fluid viscosity effect on the water column burst as well as the complex three-dimensional flow paths caused by a core shroud and standpipes were considered in this study. The three analysis scenarios were designed to investigate the above mentioned influential factors separately. In the first scenario, a two-dimensional axisymmetric reactor vessel model without any reactor internals was modeled to assess the influence of the fluid dynamics in the NSC RIA regulatory evaluation. This model has an actual RPV geometry and can be simply separated from other influential factors in order to concentrate only on investigation of the fluid viscosity effect. In the second scenario, a two-dimensional axisymmetric reactor vessel ...

2003-07-01

150

HC cylinder to cylinder deviation at idling condition in a direct injection diesel engine. Chokusetsu funshashiki diesel kikan mufuka untenji no HC kitokan hendo  

Energy Technology Data Exchange (ETDEWEB)

Causes of variation of hydrocarbon (HC) concentration in cylinder to cylinder at idling condition in a direct injection diesel engine were studied. The ratio of l/d=6 gives larger HC variation in cylinder to cylinder than the l/d=2, where l means the nozzle hole length and d means the nozzle hole diameter. This is because the condition of l/d=6 can result in the large spray penetration and increase the fuel on the combustion chamber. The spray structure changes between nozzles and also changes between nozzle holes. This is not caused by the shape of nozzle hole but is affected by the pressure change near the inlet of nozzle hole when the needle valve is lifted. The change of spray structure can change the injection volume between nozzle holes. The injection volume is less for a nozzle hole where the curved angle becomes sharp to the nozzle central angle, and is more at the opposite side. When the injection volume of the nozzle hole near the ...

1992-07-01

151

Effect of Cr content, hardness and micro structure on flow-accelerated corrosion in carbon steel pipes. Examination of replaced carbon steel pipes  

International Nuclear Information System (INIS)

68 replaced carbon steel piping in secondary system of pressurized water reactor (PWR) has been investigated by visual examination for checking thinning conditions. It is well known that the flow-accelerated corrosion (FAC) was inhibited by traces of Cr in steel. Therefore, the chemical compositions of those steels have been measured. In addition, the micro structure and hardness of those steels have been investigated. And the relationship between those material variables and FAC rate was considered. As the results, (1) The Cr contents in those steels were below 0.1 wt% except one sample. Minute quantities of chromium increase the resistance against FAC. But the water velocity was thought to be the dominant factor rather than chemical composition in steel, at least such as below 0.1%Cr. (2) Hardness of all piping has been satisfied the specifications of each materials. The hardness of steels was not correlated with wall thinning rate. (3) The ...

2008-10-01

152

Subcellular Localization of Expansin mRNA in Xylem Cells12  

UK PubMed Central (United Kingdom)

Terminal differentiation of many vascular cells involves cell wall changes. Cells first elongate their primary wall, then lay down a lignified secondary wall, which is often followed by digestion of...Full Text Available

2000-06-01

153

Numerical study of the impingement of a supersonic, axisymmetric jet on a flat plate  

International Nuclear Information System (INIS)

A numerical method for studying the flow field of an under-expanded axis-symmetric jet created by a converging-diverging nozzle and impinging on a flat plate is presented. The calculation domain of interest is a region that contains all the features of the jet that leaves the nozzle and impinges onto the plate. Axial symmetry of the domain allows a reduced 2-dimensional model to be used. FLUENT software is utilized to solve the continuity, momentum and energy equations using a coupled implicit scheme. The ideal-gas law is used to determine the gas density along with a k-#epsilon# turbulence model with a special modification to account for compressibility effects. In addition, the temperature dependency of viscosity has been taken into consideration. A number of different modeling techniques are investigated including different approximations to account for the flow inside the nozzle. Performance of non-equilibrium wall functions for near-wall ...

154

Gravitational Waves from Collapsing Domain Walls  

CERN Document Server

We study the production of gravitational waves from cosmic domain walls created during phase transition in the early universe. We investigate the process of formation and evolution of domain walls by running three dimensional lattice simulations. If we introduce an approximate discrete symmetry, walls become metastable and finally disappear. We calculate the spectrum of gravitational waves produced by collapsing metastable domain walls. Extrapolating the numerical results, we find the signal of gravitational waves produced by domain walls whose energy scale is around 10^10-10^12GeV will be observable in the next generation gravitational wave interferometers.

2010-01-01

155

Specific features and mechanisms of photoluminescence of nanostructured silicon carbide films grown on silicon in vacuum  

British Library Electronic Table of Contents (United Kingdom)

The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates under conditions of decreased growth temperatures (T gr ? 900?700?C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously, a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium laser (?excit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (?3 eV) region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements is split into a set of Lorentzian components. Th...

2011-01-01

156

Evidence for a Narrow Near-Threshold Structure in the $J/\\psi\\phi$ Mass Spectrum in $B^+\\to J/\\psi\\phi K^+$ Decays  

Energy Technology Data Exchange (ETDEWEB)

Evidence is reported for a narrow structure near the J/{psi}{phi} threshold in exclusive B{sup +} {yields} J/{psi}{phi}K{sup +} decays produced in {bar p}p collisions at {radical}s = 1.96 TeV. A signal of 14 {+-} 5 events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosity of 2.7 fb{sup -1}, collected by the CDF II detector. The mass and natural width of the structure are measured to be 4143.0 {+-} 2.9(stat) {+-} 1.2(syst) MeV/c{sup 2} and 11.7{sub -5.0}{sup +8.3}(stat) {+-} 3.7(syst) MeV/c{sup 2}.

2009-03-01

157

Sensitivity of Shallow Land Burial to neutron environment and activation cross sections in IFE thick-liquid concepts  

International Nuclear Information System (INIS)

A comprehensive assessment on the eligibility of reduced activation (RA) steels as structural chamber material in Inertial Fusion Energy thick-liquid concepts is performed. As far as alloying elements, it is shown that the activation of tungsten is a question to discuss. Regarding impurity elements, it is analyzed if they could question the possibility of obtaining real RA steels for shallow land burial (SLB). The effect of the thickness of the liquid wall on the SLB response of alloying and impurity elements is computed. It seems that a reasonable liquid thickness of about 80 cm is allowable to obtain SLB acceptability of real RA steels. And above all, we have estimated the impact of cross section uncertainties when addressing the former questions, and we identify those to be improved. The necessary improvement of some tungsten and niobium cross sections is justified. (authors)

2006-06-01

158

Reconstructions of archaeological contexts in OpenGl environments; Intelligenza artificiale per i beni culturali e le biblioteche digitali. Atti del Workshop  

Energy Technology Data Exchange (ETDEWEB)

DVR project concerns the creation of a virtual reality OpenGL system for desktop applications in archaeology. The main goal is the creation of a 3D information system using the real time interaction of OpenGL environments. The first case study implemented is the Vettii House, one of the most important and outstanding monuments in Pompei. The virtual reconstruction of these architectural models is based on very detailed photogrammetric surveys and it is connected with information layers and archaeometric data-bases regarding the state of conservation of walls, structures and any type of materials of the monument. A full 3D interface characterizes the system, comprising a high resolution texturing with detailed volumetric and geometric data. Finally, for the future, the project plans to fit the system for scientific and end users through the installation of stations on site.

2001-07-01

159

Numerical and experimental investigation of shellside characteristics for RODbaffle heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

RODbaffle heat exchanger is a kind of shell-and-tube heat exchanger with eminent performance. Because of the characteristics of tube bundle support structure, fluid flow on shellside is longitudinal and periodical, and fluid flow is of symmetry in landscape orientation. According to the fluid flow characteristics on shellside and ignoring the impact of inlet, outlet and shell wall, a periodic flow unit duct was taken as the simplified model of the shellside to perform numerical simulation by using CFD code, FLUENT. It was found that the both errors in magnitude of the main fluid velocities and heat transfer coefficients between results of simulation and that of experiment or correlations are less than 10%, and the errors of pressure drop between simulation and correlation are no more than 20%. The detailed characteristics and relation of fluid flow and heat transfer on shellside of the RODbaffle heat exchanger were analyzed using the simulation ...

2008-05-15

160

Insitu Assessment of Contaminant Containment Systems  

Environmental Research Database

Objectives(1) Evaluate various insitu techniques for determination of the permeability of slurry walls and investigate the extent of material disturbance and fracturing during drilling and testing.~%~~%~(2) Perform laboratory tests of block samples obtained from the field testing site and compare the results with field measurements.~%~~%~(3) Investigate the mechanisms of drilling using a newly developed instrumented self-boring device and develop a theoretical framework for drilling mechanisms in soils.~% [continued...]DescriptionCement-bentonite and clay liner systems are used as components of containment systems by the environmental industry to control the migration of pollution. In the interest of public safety, following construction, there is a requirement to test these structures in orde to assess if they meet the design critetia. At present this is done only indirectly via laboratory testing on samples ...

2006-01-30

161

High power testing of a 17 GHz photocathode RF gun  

Energy Technology Data Exchange (ETDEWEB)

The authors report experimental results on a high gradient 17 GHz RF photocathode gun. The photocathode RF gun is a novel electron beam source intended to meet the requirements set by future high-energy linear colliders and next generation free electron lasers. A coupled pair of pillbox TM{sub 010}-like resonators is excited by sidewall coupled microwaves at 17 GHz. A picosecond ultraviolet laser pulse illuminates one wall of the structure at the axis of symmetry. Electrons are released by the photoelectric effect and are accelerated by the electric field of the microwaves in the cavity. The high frequency of operation raises the RF breakdown limit allowing strong electric fields to be used. In turn, the intense fields result in rapid acceleration of the electrons to relativistic speeds and reduced space charge induced emittance growth.

1996-12-31

162

FFTF reactor characterization program  

International Nuclear Information System (INIS)

Preparations are under way for the initial startup and testing of the Fast Flux Test Facility (FFTF). The FFTF Reactor Characterization Program is that part of the startup test plan that deals with the determination of the neutron, gamma ray and thermal hydraulic characteristics of the reactor. This program encompasses measurements and calculations of: neutron spectra, flux and fluence; gamma-ray spectra, dose and heating; fission rate distributions; capture rate distributions; other reaction rates of interest; fission product yields; and thermal hydraulic data. Measurements of these parameters will be made in the reactor core and reflectors, will extend vertically downward to the vicinity of the core support structure and upward to the top of the sodium pool, and will extend radially outward to include in-vessel fuel storage locations and the cavity between the reactor vessel and the concrete wall.

163

Experimental study of convective self-oscillations near the lateral surface of a bubble in a plane rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Experimental investigations have been performed to study solutal convection around an air bubble squeezed between the walls of a horizontal rectangular channel, filled by an aqueous solution of surfactant with vertically stratified concentration. A convective motion in the fluid develops due to the solutocapillary Marangoni forces at the bubble lateral free surface. The structure and evolution of the convective flow and the surfactant concentration fields in the channel have been investigated using interferometric technique. The tests revealed the development of self-oscillatory modes near the bubble surface, related to the interaction between solutocapillary and solutogravitational motion mechanisms. The time dependences of the oscillations period are analyzed in relation to the average c...

2008-01-01

164

Donut-shaped high-dose configuration for proton beam radiation therapy  

Energy Technology Data Exchange (ETDEWEB)

Background: the authors report on the conception and first clinical application of a donut-shaped high-dose configuration for proton therapy (PT). This approach allows one to intensify target volume dose coverage for targets encompassing a critical, dose-limiting structure - like here, the cauda equina -, whilst delivering minimal dose to other healthy structures surrounding the target, thereby reducing the integral dose. Methods and results: intensity-modulated PT methods (IMPT) for spot scanning were applied to create and deliver a donut-shaped high-dose configuration with protons, allowing treating > 75% of the target with at least 95% of the prescribed dose of 72.8 CGE, whilst restricting dose to the cauda equina to 60-65 CGE. Integral dose was lower by a factor of 3.3 as compared to intensity-modulated radiotherapy with photons (IMXT). Conclusion: IMPT and spot scanning technology allow a ...

2005-01-01

165

Donut-shaped high-dose configuration for proton beam radiation therapy  

International Nuclear Information System (INIS)

Background: the authors report on the conception and first clinical application of a donut-shaped high-dose configuration for proton therapy (PT). This approach allows one to intensify target volume dose coverage for targets encompassing a critical, dose-limiting structure - like here, the cauda equina -, whilst delivering minimal dose to other healthy structures surrounding the target, thereby reducing the integral dose. Methods and results: intensity-modulated PT methods (IMPT) for spot scanning were applied to create and deliver a donut-shaped high-dose configuration with protons, allowing treating > 75% of the target with at least 95% of the prescribed dose of 72.8 CGE, whilst restricting dose to the cauda equina to 60-65 CGE. Integral dose was lower by a factor of 3.3 as compared to intensity-modulated radiotherapy with photons (IMXT). Conclusion: IMPT and spot scanning technology allow a ...

2005-01-01

166

Constraints on target chamber first wall and target designs that will enable NIF debris shields to survive  

CERN Document Server

Constraints on target chamber first wall and target designs that will enable NIF debris shields to survive

1999-01-01

167

Aortic non communicating dissections. A study with helical CT  

International Nuclear Information System (INIS)

The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall ...

2000-09-01

168

[Case of bladder perforation due to the obturator nerve reflex during transurethral resection (TUR) of bladder tumor using the TUR in saline (Turis) system under spinal anesthesia].  

Science.gov (United States)

Bladder perforation due to the obturator nerve reflex (ONR) is a serious complication during TUR of bladder tumor using the conventional TUR system; requiring monopolar electrocautery and non-conductive solution as perfusate. Recently, the TURis system, which employs bipolar electrocautery and physiological saline as perfusate, has been developed. Electrical resistance of physiological saline and human tissues are approximately 40 and 500 omega, respectively. Thus, theoretically, electrical current flows between the resection loop and the recovery electrode integrated in the outer sleeve of the endoscope, without forming electrical circuit in the patient's body; suggesting possible elimination of the ONR. Here we describe a case of bladder perforation during surgery using the TURis system; the ONR was exaggerated during the procedure to stop bleeding at the lateral wall using bipolar electrocautery. In addition to this case, there have been a ...

2010-03-01

169

Visualization of a gas-liquid metal two-phase natural circulation flow by a real-time neutron radiography technique  

Energy Technology Data Exchange (ETDEWEB)

In a breeder-type nuclear power plant, liquid metal is used as a coolant due to the high heat capacity factor. Also, some proposals for fusion reactor blanket design include liquid metal as a possible coolant. In both cases the understanding of natural circulation of liquid-metal flow behavior is an integral part of the thermal hydraulic analysis, especially under two-phase flow conditions. Experimental investigations have been conducted to study a liquid metal two-phase natural circulation flow system. A lead-bismuth (PbBi) eutectic mixture is used as a working fluid in a heated metal walled natural circulation loop. Gas injection induces natural circulation through the gas-lift mechanism. A real-time neutron radiography system is used to visualize the two-phase mixture, specifically the interface and the flow regime. Measurements of void fraction, void fluctuation and bubble propagation are performed.

1996-06-01

170

Visualization of a gas-liquid metal two-phase natural circulation flow by a real-time neutron radiography technique  

International Nuclear Information System (INIS)

In a breeder-type nuclear power plant, liquid metal is used as a coolant due to the high heat capacity factor. Also, some proposals for fusion reactor blanket design include liquid metal as a possible coolant. In both cases the understanding of natural circulation of liquid-metal flow behavior is an integral part of the thermal hydraulic analysis, especially under two-phase flow conditions. Experimental investigations have been conducted to study a liquid metal two-phase natural circulation flow system. A lead-bismuth (PbBi) eutectic mixture is used as a working fluid in a heated metal walled natural circulation loop. Gas injection induces natural circulation through the gas-lift mechanism. A real-time neutron radiography system is used to visualize the two-phase mixture, specifically the interface and the flow regime. Measurements of void fraction, void fluctuation and bubble propagation are performed.

1996-03-10

171

Study on the application of a geothermal heat pump; Etude sur l`application d`une pompe a chaleur geothermique  

Energy Technology Data Exchange (ETDEWEB)

The heating system of the `Centre integre de mecanique industrielle de la Chaudiere`, in Saint-Georges, Quebec, is based on a solar wall and a geothermal heat pump with a glycol/water mixture circulating in 44 wells that are 100 m deep. With installation costs below $25 per sq.m, more than 85 per cent of the heating needs of the 9500 sq.m centre were supplied by geothermal power. The geothermal heat pump is composed of a well field and two 211-kW cooling units, each equipped with four coiled compressors. In winter, heat is pumped from the earth and in summer, a heat exchanger with control valves allows to heat to be dumped back into the earth. The monitoring and simulation of the system proved its efficiency, considering the climatic conditions in Quebec. The annual consumption of geothermal heating is 0.146 GJ per sq.m, which is very low compared to the consumption of electric heating (0.286 GJ per sq.m) or oil heating (0.419 GJ per sq.m). 4 ...

1996-12-01

172

Solidification of radioactive waste effluents  

Energy Technology Data Exchange (ETDEWEB)

A process and apparatus for solidifying radioactive waste liquid containing dissolved and/or suspended solids is disclosed. The process includes chemically treating for pH adjustement and precipitation of solids, concentrating solids with a thin-film evaporator to provide liquid concentrate containing about 50% solids, and drying the concentrate with heated mixing apparatus. The heated mixing apparatus includes a heated wall and working means for shearing dried concentrate from internal surfaces and subdividing dry concentrate into dry, powdery particles. The working means includes a rotor and helical means for positively advancing the concentrate and resulting dry particles from inlet to outlet of the mixing apparatus. The dry particles may also be encapsulated in a matrix material. Entrained particles in the vapor stream from the evaporator and mixer are removed in an integral particle separator and the vapor is subsequently condensed and may ...

1983-10-11

173

Research and development on probe inserting method into steam generator helically coiled tubes for in-service inspection  

International Nuclear Information System (INIS)

Helically coiled tubes of steam generators (SG) in FBR are boundaries between sodium and water/steam. Therefore, to assure the integrity of tubes, it is necessary to inspect the tubes nondestructively for in service or after a sodium-water reaction accident. In order to make it possible to conduct in-service inspection of SG tubes, we have studied on eddy current probes and probe inserting methods. As for the probe inserting method, IHI designed a fluid driving type which consists of a model probe and signal cable with float balls and driven by air pressure force. Presented in this paper is the authors' report, which describes the fluid driving type as an effective method to insert an eddy current probe into helically coiled tubes. The outline of the test results is as follows: 1. It was possible to insert the probe into 65 meter length helically coiled tubes. 2. We could detected, as anticipated, a defect (outer circumferential wall thinning ...

1979-01-01

174

Renewable energy in the urban setting: Year two  

Energy Technology Data Exchange (ETDEWEB)

At the 1996 Conference in North Carolina, The Green Institute began to share its story. Their presentation this year will cover where they are in the design process and their plans for using solar and wind technologies in the development of an Eco-Industrial Park and Business Incubator. Located in a Federal Enterprise Community in Minneapolis, this project borrows sustainable and green building principles using the Rocky Mountain Institute and Solar Living Center as models. Using a change in the paradigm regarding how industry does business, The Green Institute is joining with developments across the country that are putting together Eco-Industrial Parks which use closed loop production systems to reduce waste and emissions generated from manufacturing processes. Using renewable energy, both solar and wind, presents challenges both in the integration of systems on this small site and the educational opportunities with a large potential audience outside the ...

1997-12-31

175

Relaxant effects of hexosamines on isolated small human placental arteries  

DEFF Research Database (Denmark)

Wharton's jelly contains large amounts of hyaluronic acid, and glucosamine is an important constituent of this macromolecule. In order to evaluate the placental vascular effects of this aminosugar, small chorionic and stem villous arteries were dissected from placental specimens obtained at normal term vaginal deliveries (n = 15). Ring preparations were mounted in organ baths, and isometric wall tensions were measured. Glucosamine and its epimer galactosamine (5 X 10(-4) to 10(-2) M) produced marked relaxation of contractions induced by PGF2 alpha (10(-5) M) in both chorionic and stem villous arteries. The effect was unchanged after pretreatment with atropin, propranolol and indomethacin. The relaxant effect of the neutral sugar mannose was less pronounced compared with that of the hexosamines. Total tissue concentrations of placental hexosamines have been reported within the range needed to produce placental vascular relaxation in the present study. However, the ...

1987-01-01

176

Prospects for controlling animal parasitic nematodes by predacious micro fungi.  

Science.gov (United States)

Resistance against anthelmintics is widespread, particularly in parasitic nematode populations of small ruminants. Several new techniques or supplements have been developed or are under investigation. Biological control (BC) is one of these new methods. The net-trapping predacious fungus Duddingtonia flagrans produces thick walled resting spores, chlamydospores, which are able to survive passage through the gastrointestinal tract of cattle, horses, sheep and pigs. Under Danish climatic conditions it has been shown that the number of parasite larvae on pasture and the worm burden of the grazing animals is significantly reduced when animals are fed spores during the initial 2-3 months of the grazing season. Work with D. flagrans in France, Australia, USA, and Mexico has confirmed the strong BC potential of this fungus. Today much work is going into development of suitable delivery systems for grazing livestock worldwide. Ultimately, BC should be implemented in ...

2000-01-01

177

Oil shale, tar sand, coal research, advanced exploratory process technology jointly sponsored research  

Energy Technology Data Exchange (ETDEWEB)

Accomplishments for the quarter are presented for the following areas of research: oil shale, tar sand, coal, advanced exploratory process technology, and jointly sponsored research. Oil shale research includes; oil shale process studies, environmental base studies for oil shale, and miscellaneous basic concept studies. Tar sand research covers process development. Coal research includes; underground coal gasification, coal combustion, integrated coal processing concepts, and solid waste management. Advanced exploratory process technology includes; advanced process concepts, advanced mitigation concepts, and oil and gas technology. Jointly sponsored research includes: organic and inorganic hazardous waste stabilization; development and validation of a standard test method for sequential batch extraction fluid; operation and evaluation of the CO[sub 2] HUFF-N-PUFF Process; fly ash binder for unsurfaced road aggregates; solid state NMR analysis of Mesa Verde Group, ...

1992-01-01

178

Examination of scaling criteria for nuclear reactor thermal-hydraulic test facilities  

International Nuclear Information System (INIS)

Scaling criteria for a natural-circulation loop are examined. The present state of knowledge of scaling to obtain similarity during single- and two-phase flow conditions in a closed loop are reviewed, and an alternative development of two-phase similarity parameters is presented. The loop scaling criteria are the results of analyses in which flow from one component to another is considered. In this work, boundary conditions for the closed loop are developed to obtain scaling criteria for leak flow, injection flow, and heat loss to ambient. The leak scaling criteria are specialized for modeling approaches using prototypic fluid at prototypic or reduced pressures. The derived scaling parameters are examined for their application to two existing scaled test facilities: the Multi-Loop Integral System Test (MIST) facility at Babcock and Wilcox, and the UMCP 2 x 4 facility at the University of Maryland College Park. The heat loss similarity analysis is performed in ...

1987-01-01

179

Design of the heat receiver for the U.S./Russia solar dynamic power joint flight demonstration  

Energy Technology Data Exchange (ETDEWEB)

A joint US/Russia program is being conducted to develop, fabricate, launch, and operate a solar dynamic demonstration system on Space Station Mir. The goal of the program is to demonstrate and confirm that solar dynamic power systems are viable for future space applications such as the International Space Station Alpha. The major components of the system include a heat receiver, a closed Brayton cycle power conversion unit, a power conditioning and control unit, a concentrator, a radiator, a thermal control system, and a Space Shuttle carrier. This paper discusses the design of the heat receiver component. The receiver comprises a cylindrical cavity, the walls of which are lined with a series of tubes running the length of the cavity. The engine working fluid, a mixture of xenon and helium, is heated by the concentrated sunlight incident on these tubes. The receiver incorporates integral thermal storage, using a eutectic mixture of lithium ...

1995-12-31

180

Re-Analysis of In-Service Inspection of Pressure Tubes and Feeder Pipes in Wolsong Unit 1  

Energy Technology Data Exchange (ETDEWEB)

Since the first commercial operation in 1983, Wolsung unit 1 has experienced several aging phenomena, especially in pressure tubes and feeder pipes. In case of pressure tubes, in-service inspections (ISI) revealed that a major portion of inspected tubes was in contact with calandria tubes. The likelihood of blister formation was a safety concern because it is a potential threat to pressure tube integrity. Wolsung unit 1 was, therefore, subjected to the SLAR (Spacer Location And Reposition) work to separate the contacted pressure tubes from calandria tubes. In this paper, experience of in-service inspection to the pressure tubes will be discussed including the irradiation creep elongation and CIGAR (Channel Inspection and Gauging Apparatus for Reactors) examination of pressure tubes. On the other hand, the problem of wall thinning in the feeder pipes became of great concern since 1996. Inspections, in compliance with CSA N285.4, were conducted ...

2005-07-01

181

Re-Analysis of In-Service Inspection of Pressure Tubes and Feeder Pipes in Wolsong Unit 1  

International Nuclear Information System (INIS)

Since the first commercial operation in 1983, Wolsung unit 1 has experienced several aging phenomena, especially in pressure tubes and feeder pipes. In case of pressure tubes, in-service inspections (ISI) revealed that a major portion of inspected tubes was in contact with calandria tubes. The likelihood of blister formation was a safety concern because it is a potential threat to pressure tube integrity. Wolsung unit 1 was, therefore, subjected to the SLAR (Spacer Location And Reposition) work to separate the contacted pressure tubes from calandria tubes. In this paper, experience of in-service inspection to the pressure tubes will be discussed including the irradiation creep elongation and CIGAR (Channel Inspection and Gauging Apparatus for Reactors) examination of pressure tubes. On the other hand, the problem of wall thinning in the feeder pipes became of great concern since 1996. Inspections, in compliance with CSA N285.4, were conducted ...

2005-10-27

182

Liquid-metal flow in a sharp elbow in a uniform transverse magnetic field  

Science.gov (United States)

In the self-cooling blankets of the Tokamak fusion reactor, a liquid metal, namely liquid lithium, is pumped through a system of ducts to transfer heat and capture neutrons. One of the blanket designs proposed in Argonne National Laboratory's Blanket Comparison and Selection study uses a combination of poloidal and toroidal ducts in order to maximize heat transfer while minimizing net pressure drop. In the design, the poloidal and toroidal ducts meet at sharp, abrupt corners. They were modelled as two identical, straight, semi-infinite, thin-walled, rectangular ducts with 45{degree} miters and joined at a 90{degree} angle in the plane of a strong, uniform magnetic field. While in the toroidal containment vessel (i.e. the blanket), the liquid lithium is subjected to a large electromagnetic body force due to the presence of a strong magnetic field. This body force so dominates the flow as to make the inertial and viscous forces negligible everywhere, except ...

1989-01-01

183

Can simulation measurements be used to predict the irradiated lung volume in the tangential fields in patients treated for breast cancer  

Energy Technology Data Exchange (ETDEWEB)

A simple method of estimating the amount of lung irradiated in patients with breast cancer would be of use in minimizing lung complications. To determine whether simple measurements taken at the time of simulation can be used to predict the lung volume in the radiation field, we performed CT scans as part of treatment planning in 40 cases undergoing radiotherapy for breast cancer. Parameters measured from simulator films included: (a) the perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall at the center of the field (CLD); (b) the maximum perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall (MLD); and (c) the length of lung (L) as measured at the posterior tangential field edge on the simulator film. CT scans of the chest were performed with the patient in the treatment position with 1 cm slice intervals, covering lung apex ...

1990-01-01

184

Weld integrity of the superconducting cable aluminium jackets of W7-X  

British Library Electronic Table of Contents (United Kingdom)

The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fur Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The ...

2009-01-01

185

Web-Based Enterprise Information Systems Development: The Integrated Methodology  

CERN Document Server

The paper considers software development issues for large-scale enterprise information systems (IS) with databases (DB) in global heterogeneous distributed computational environment. Due to high IT development rates, the present-day society has accumulated and rapidly increases an extremely huge data burden. Manipulating with such huge data arrays becomes an essential problem, particularly due to their global distribution, heterogeneous and weak-structured character. The conceptual approach to integrated Internet-based IS design, development and implementation is presented, including formal models, software development methodology and original software development tools for visual problem-oriented development and content management. IS implementation results proved shortening terms and reducing costs of implementation compared to commercial software available.

2006-01-01

186

The geometry emerging from the symmetries of a quantum system  

CERN Document Server

We investigate the relation between the symmetries of a quantum system and its topological quantum numbers, in a general C*-algebraic framework. We prove that, under suitable assumptions on the symmetry algebra, there exists a generalization of the Bloch-Floquet transform which induces a direct-integral decomposition of the algebra of observables. Such generalized transform selects uniquely the set of "continuous sections" in the direct integral, thus yielding a Hilbert bundle. The emerging geometric structure provides some topological invariants of the quantum system. Two running examples provide an Ariadne's thread through the paper. For the sake of completeness, we review two related theorems by von Neumann and Maurin and compare them with our result.

2009-01-01

187

Structural integrity of whipping pipes following postulated rupture - a contribution to strain levels acceptable under faulted conditions. Integritaetsverhalten von Rohrleitungen nach unterstelltem Rundabriss - ein Beitrag zur Dehnungsabsicherung bei Schadensfaellen  

Energy Technology Data Exchange (ETDEWEB)

By tests about pipe failure under extreme bending, moment at cross sections affected by circumferential cracks, admissible strains for securing the integrity in the area of a flow link are indicated. These are 7% for austenic and ferritic materials in the undisturbed cross section. From d/t-ratios of 20 onwards the strains are limited by pipe bulging on the pressure-load side. In this connection, circumferential flaws do not have any influence on the behaviour on the strained side, when their expansion does not exceed the investigated limitis of <60 circumferential expansion and crack depth of 0,3 t. (orig.)

1991-01-01

188

Incorporating phenolic compounds opens a new perspective to use zein films as flexible bioactive packaging materials  

British Library Electronic Table of Contents (United Kingdom)

To eliminate their classical brittleness and flexibility problems zein films were plasticized by incorporation of different phenolic acids (gallic acid (GA), p-hydroxy benzoic acid (HBA) or ferulic acids (FA)) or flavonoids (catechin (CAT), flavone (FLA) or quercetin (QU)). The use of GA, CAT, FA and HBA at 3 mg/cm2 eliminated the brittleness of films and gave highly flexible films showing elongations between 135% and 189%, while FLA and QU caused no considerable effect on film elongation. The films containing FA and HBA showed extreme swelling and lost their structural integrity when hydrated in distilled water. In contrast, CAT and GA containing films maintained their integrity following hydration. Most of the GA (up to 93%) and a considerable portion of CAT (up to 60%) in the films exis...

2011-01-01

189

Diagnostic imaging in pregraduate integrated curricula; Radiologie in einem praegraduellen problembasiert-integrierten Medizincurriculum  

Energy Technology Data Exchange (ETDEWEB)

Pregraduate medical curricula are currently undergoing a reform process that is moving away from a traditional discipline-related structure and towards problem-based integrated forms of teaching. Imaging sciences, with their inherently technical advances, are specifically influenced by the effects of paradigm shifts in medical education. The teaching of diagnostic radiology should be based on the definition of three core competencies: in vivo visualization of normal and abnormal morphology and function, diagnostic reasoning, and interventional treatment. On the basis of these goals, adequate teaching methods and e-learning tools should be implemented by focusing on case-based teaching. Teaching materials used in the fields of normal anatomy, pathology, and clinical diagnosis may help diagnostic radiology to play a central role in modern pregraduate curricula. (orig.)

2007-11-15

190

An integrated approach to coastal erosion problems in northern Tuscany (Italy): Littoral morphological evolution and cell distribution  

British Library Electronic Table of Contents (United Kingdom)

Occupation of the coast has significantly increased in recent decades, mostly due to a greater demand for recreation and tourism. Today, erosion threatens many human-made structures and activities, requiring an integrated approach for the understanding of coastal dynamics and identification of alternatives to associated problems. This study investigates a 64km-long coastal physiographic unit in the northern microtidal littoral of Tuscany (Italy). Vertical aerial photographs and direct field surveys were used to retrieve changes in shoreline position over 1938-1997 and 1997-2005 time intervals. Significant beach accretion was observed during the first period updrift of Carrara (84m) and Viareggio (280m) harbours and at Marina di Pietrasanta (100m), whereas severe erosion occurred downcoast ...

2011-01-01

191

Adaptive smearing for Brillouin zone integration  

British Library Electronic Table of Contents (United Kingdom)

Abstract We suggest a simple scheme for automatically determining the width parameter of smearing methods of the Brillouin zone integration in electronic structure calculation. The scheme retains one free parameter that at any time can be eliminated by choosing a denser k-space mesh until the desired accuracy is obtained. The tests are carried out in the context of Methfessel-Paxton smearing. This adaptive Gaussian smearing (AGS) is easily implemented, variational with respect to partial occupancies and free from spurious occupancies that are negative or larger than one. Its convergence properties are similar to those obtained with the modified tetrahedron method for energy resolution of -0.1 meV. 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011

2011-01-01

192

In vitro MRI of brain development  

International Nuclear Information System (INIS)

In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular zone. The basal ...

2006-02-01

195

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 ...

2007-02-15

196

Integrated experimental test program on waterhammer pressure pulses and associated structural responses within a feedwater sparger  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the methods and systems as utilized in an integrated experimental thermohydraulic/mechanics analysis test program on waterhammer pressure pulses within a revised feedwater sparger of a Loviisa generation VVER-440-type reactor. This program was carried out in two stages: (1) measurements with a strictly limited set of operating parameters at Loviisa NPP, and (2) measurements with the full set of operating parameters on a test article simulating the revised feedwater sparger. The experiments at Loviisa NPS served as an invaluable source of information on the nature of waterhammer pressure pulses and structural responses. These tests thus helped to set the objectives and formulate the concept for series of tests on a test article to study the water hammer phenomena. The heavily instrumented full size test article of a steam generator feedwater sparger was placed within a pressure vessel simulating the steam generator. The ...

1997-12-31

197

Radiation factors specifying safety in reactor compartments handling in the process of decommissioning nuclear-powered submarines  

International Nuclear Information System (INIS)

The main problems arising in decommissioning nuclear-powered submarines (NPS) relate to choosing a concept of handling reactor compartments followed by handling technology development. Reactor compartments (RC) are characterized with extremely space-saving or integral layout of large-size power equipment and systems, restricted access for dismantling, high radiation dose rates in a number of bays of RC. The above RC features pose a problem to find optimum option of RC utilization which on the one hand would be the most cost efficient, and the safest as possible on the other, i.e. dose commitments of personnel involved should be minimum, and effect on population and environment should be negligible. The main radiation factors specifying safety in RC handling at any decommissioning stage are as follows: (1) total radioactivity integrated in reactor facility (RF); (2) distribution of this radioactivity through RF equipment and ...

1996-03-10

198

Individual Music Therapy with Persons with Frontotemporal Dementia : Singing Dialogue. Reprint of article first publised in NJMT 14(2) 2005, pp. 91-106  

DEFF Research Database (Denmark)

It is possible to slow down the progression of Alzheimer's disease with pharmacological treatment. When this treatment is given to people with types of dementia that affect the frontal and temporal lobes (Frontotemporal Dementia) the results are discouraging. It is observed that the patients show pronounced restlessness and mania. In this article we describe a nonpharmacological psychosocial approach, music therapy, and how it is possible to work with this method when constitutional, regulative, dialogical, and integrative aspects are included. The focus is on therapeutic singing where well-known songs are applied in order to build up structure and stability and/or as means of arousal regulation. Songs with personal meaning make it possible to acknowledge the person's emotions, breaking the social isolation, and meeting the music therapy participant's psychosocial needs. The clinical approach is an integration of a ...

2007-01-01

199

Development of flame retardant PV module encapsulants: Volume 1. Final report  

Energy Technology Data Exchange (ETDEWEB)

This Phase 1 final report covers the work performed by Springborn Testing and Research, Inc., for the period October 1, 1997 to June 30, 1998 under the Department of Energy Cooperative Agreement Number DE-FC36-97GO10255, entitled Development of Flame Retardant PV Module Encapsulants. While use of roof-mounted arrays has always been an attractive means of deploying PV, only within recent years have such building integrated concepts (BIPV) found renewed interest among module makers and end-users. Prior to building integrated and rooftop applications, flammability requirements for modules have not been a great industry concern. However, with growing interest in BIPV and the requirement for building code requirements for commercial and industrial structures, flammability issues have become a barrier to entry for many module constructions into this potentially huge domestic market for PV. The overall goal of the 3 phase PV BONUS ...

1998-06-01

200

Optical Fiber Sensor Package Development for the SIT of Containment Structure  

International Nuclear Information System (INIS)

Various types of nuclear power plants are being constructed and operated in Korea, and in terms of regulatory control, a method of examining and evaluating the structural integrity of containment structure is being used. Generally, after the construction has been completed, all containment structure go through a Structural Integrity Test(hereinafter SIT) in which the displacement occurring in a structure under greater internal pressure than it was designed for is measured and the result is comparatively assessed with the allowed criteria. Most of the nuclear power plants in Korea are American type plants and their SIT uses the Invar-wire and Extensometer methods. These existing methods are expected to be used for the APR1400 plant currently being built unless some other reliable alternative technique is presented. This tendency can be ...

2010-10-01

201

Laser Sensor Package Development for the SIT of Containment Structure  

International Nuclear Information System (INIS)

Various types of nuclear power plants are being constructed and operated in Korea, and in terms of regulatory control, a method of examining and evaluating the structural integrity of containment structure is being used. Generally, after the construction has been completed, all containment structure go through a Structural Integrity Test(hereinafter SIT) in which the displacement occurring in a structure under greater internal pressure than it was designed for is measured and the result is comparatively assessed with the allowed criteria. Most of the nuclear power plants in Korea are American type plants and their SIT uses the Invar-wire and Extensometer methods. These existing methods are expected to be used for the APR1400 plant currently being built unless some other reliable alternative technique is presented. This tendency can be ...

2010-10-01

202

Study of structural, thermodynamical and dynamical properties of molecular liquids confined in nano-porous materials; Etude des proprietes structurales, thermodynamiques et dynamiques de liquides moleculaires confines dans des materiaux nanoporeux modeles  

Energy Technology Data Exchange (ETDEWEB)

When liquids are confined in nano-scopic dimensions, their properties differ from the corresponding bulk liquid, due to their reduced dimensionality and surface effects. Phase transition temperatures and pressures are often shifted from the bulk values and new phases can appear due to the strong interactions of the molecules with the confining walls. We have studied the structural and dynamical properties of aromatic liquids such as benzene, toluene, and ortho-terphenyl confined in nano-porous materials, MCM-41 and SBA-15, synthesized and characterized in our laboratory. A non-trivial dependence of the glass transition temperature, T{sub g}, on the pore size and surface treatment of nano-porous materials is confirmed and interpreted as resulting from a competition between the fluid-wall and fluid-fluid intermolecular interactions. An increase of T{sub g} is observed for small pore sizes and attractive surface while T{sub g} ...

2006-11-15

203

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 ...

1988-03-01

204

Recognition and Detoxification of the Insecticide DDT by Drosophila melanogaster Glutathione S-Transferase D1  

Energy Technology Data Exchange (ETDEWEB)

GSTD1 is one of several insect glutathione S-transferases capable of metabolizing the insecticide DDT. Here we use crystallography and NMR to elucidate the binding of DDT and glutathione to GSTD1. The crystal structure of Drosophila melanogaster GSTD1 has been determined to 1.1 {angstrom} resolution, which reveals that the enzyme adopts the canonical GST fold but with a partially occluded active site caused by the packing of a C-terminal helix against one wall of the binding site for substrates. This helix would need to unwind or be displaced to enable catalysis. When the C-terminal helix is removed from the model of the crystal structure, DDT can be computationally docked into the active site in an orientation favoring catalysis. Two-dimensional {sup 1}H,{sup 15}N heteronuclear single-quantum coherence NMR experiments of GSTD1 indicate that conformational changes occur upon glutathione and DDT binding and the residues that ...

2010-06-14

205

Neutronic aspects of the safety and environmental performance of silicon carbide as blanket structural material  

Energy Technology Data Exchange (ETDEWEB)

Safety and environmental assessments have been made of conceptual fusion power plant designs employing silicon carbide composites (SiC/SiC) as the first wall and blanket structure material. These have used similar analysis methods to earlier studies of designs based on vanadium alloy or low-activation martensitic steel, allowing direct comparisons. The very low short-term activation of silicon carbide results in an almost insignificant level of decay heat in postulated loss of coolant accidents, and a lower {gamma}-dose rate on the timescale of relevance to handling for maintenance operations. However on the longer time-scale, of interest in possible recycling operations, decommissioning and waste management, SiC/SiC appears to perform no better than vanadium alloy or low-activation martensitic steel, due in part to the activation of impurities in a realistic composition. Furthermore, its increased neutron transparency may result in higher ...

2001-04-01

206

Microstructure and magnetic properties of nanocrystalline Fe75Si20M5 (M = Al, B, Cr) powders  

International Nuclear Information System (INIS)

Nanocrystalline Fe75Si20M5 (M = Al, B and Cr) powders were synthesized by mechanical alloying in a planetary ball mill from high purity elemental powders. Evolution of non-equilibrium solid solutions of ?-Fe[Si,(Al, B, Cr)] with a nanocrystalline structure was accompanied by the introduction of a large number of dislocation defects in the course of the milling process. Fe sites get substituted by Si and M (M = Al, B, Cr) atoms during the milling process. The structural change and the resulting disorder are reflected in the changes in the lattice parameter and average magnetic moment of the powders milled for various time periods. The effective magnetic anisotropy increases linearly with the milling time. An increase in coercivity with increasing milling time was observed which could be attributed to the introduction of dislocations and the reduction in the powder particle size during milling. The presence of dislocations and grain boundaries ...

2008-08-21

207

Diverter bop system and method for a bottom supported offshore drilling rig  

Energy Technology Data Exchange (ETDEWEB)

A system and method for installing a fluid flow controller and telescoping spools beneath an offshore bottom supported drilling rig rotary table is disclosed. Upper and lower telescoping spools are provided for initially connecting a Diverter/BOP convertible fluid flow controller between structural casing in the well and a permanent housing beneath the drilling rig rotary table. Clamp means are provided for clamping the rig vent line to an opening in the housing wall of the fluid flow controller during drilling of the borehole through the structural casing in preparation for setting and cementing the conductor casing. In that mode, the system is adapted as a diverter system. After the well is drilled for the conductor casing and the conductor casing is cemented and cut off at its top, a mandrel is fitted at the top of the conductor casing to which the lower end of the lower spool may be connected. The system may be used in ...

1985-06-25

208

Development of structural steels for nuclear application - Enhancement of corrosion resistance of stainless steels for nuclear power plant  

Energy Technology Data Exchange (ETDEWEB)

Fe-Cr-Mn stainless steel is one of the candidate materials for the 1`st wall materials and structural applications of fusion reactor as regards reduced radioactivation properties than Fe-Cr-Ni austenitic stainless steels. This report deals with the effects of annealing and aging heat treatment on the microstructure, mechanical properties and corrosion resistance of Fe-Cr-Mn alloys varying Mn and W contents, which were made using vacuum high frequency induction furnace. Increasing Mn contents, austenite phase was increased, and maximum .epsilon. martensite phase was formed at about 21% Mn. W-addition made small amount of ferrite phase in the matrix, and the ferrite contents were increased with raising annealing temperature. Increased Mn contents reduced tensile stress and yield stress but increased the elongation. W-addition raised the high temperature tensile properties. The variation of Mn contents had no influenced on corrosion resistance. ...

1996-07-01

209

CFD analysis on the flow distribution of steam generator of SMART-P  

Energy Technology Data Exchange (ETDEWEB)

The Computational Fluid Dynamics(CFD) study was conducted to assess the new design concept introduced to solve the issues on the flow deviation between SG cassettes and the supporting structure design of the flow distributing plate subjected to the flow induced vibration. Flow field from MCP to the bottom of SG was modeled for 2-dimensional(2D) CFD analysis and then sensitivity analysis on major design parameters was conducted using commercial CFD code, Fluent. The cases for detailed 3D analysis were selected based on the result of 2D analysis and the detailed 3-dimensional(3D) analysis was conducted for these selected cases using Fluent code. Flow field was modeled by RNG model and wall function, 2nd upwind scheme, porous model, structured or hybrid grid. The analysis result shows that the maximum deviation of flow distribution between SG cassettes was reduced upto about 0.1% and the pressure loss from the SG header to SG ...

2003-12-01

210

Acoustic metamaterials for sound focusing and confinement  

Energy Technology Data Exchange (ETDEWEB)

We give a theoretical design for a locally resonant two-dimensional cylindrical structure involving a pair of C-shaped voids in an elastic medium which we term as double 'C' resonators (DCRs) and imbedded thin stiff bars, that displays the negative refraction effect in the low frequency regime. DCRs are responsible for a low frequency band gap which hybridizes with a tiny gap associated with the presence of the thin bars. Using an asymptotic analysis, typical working frequencies are given in closed form: DCRs behave as Helmholtz resonators modeled by masses connected to clamped walls by springs on either side, while thin bars behave as a periodic bi-atomic chain of masses connected by springs. The discrete models give an accurate description of the location and width of the stop band in the case of the DCR and the first two dispersion bands for the periodic thin bars. We then combine our asymptotic formulae for arrays of DCR ...

2007-11-15

211

Acoustic metamaterials for sound focusing and confinement  

International Nuclear Information System (INIS)

We give a theoretical design for a locally resonant two-dimensional cylindrical structure involving a pair of C-shaped voids in an elastic medium which we term as double 'C' resonators (DCRs) and imbedded thin stiff bars, that displays the negative refraction effect in the low frequency regime. DCRs are responsible for a low frequency band gap which hybridizes with a tiny gap associated with the presence of the thin bars. Using an asymptotic analysis, typical working frequencies are given in closed form: DCRs behave as Helmholtz resonators modeled by masses connected to clamped walls by springs on either side, while thin bars behave as a periodic bi-atomic chain of masses connected by springs. The discrete models give an accurate description of the location and width of the stop band in the case of the DCR and the first two dispersion bands for the periodic thin bars. We then combine our asymptotic formulae for arrays of DCR and thin-bars to ...

2007-11-01

212

Abrasive-waterjet machining of isogrid structures  

Science.gov (United States)

An experimental investigation was conducted to determine the feasibility of machining isogrid structures with abrasive-waterjets (AWJs). The main objective was to mill isogrid patterns in surfaces with accurate depth control using an AWJ. Three different approaches using AWJs were tested: linear cutting of isogrid patterns for diffusion bonding, milling with conventional AWJ nozzles, and milling with a single-angled rotary AWJ nozzle. It was shown that pocket milling with conventional AWJs is the most feasible of those tested. The milling can be done internally on preformed aluminum tubes, and the AWJ can also be used on materials other than aluminum. Accurate depth control can be achieved at high productivity rates. As an example, it is projected that a 48-inch-diameter skirt 12 inches high could be milled with an isogrid pattern in 6.3 hours. Milled isogrid patterns can be controlled to 0.001 inch, and thin walls of less than 0.025 inch are ...

1990-12-01

213

Transfer of lead through the rats intestinal wall  

International Nuclear Information System (INIS)

... females in vitro intestines lead 203 mucous membranes radionuclide kinetics

216

In-situ maintenance of low-Z limiters in reactors  

Energy Technology Data Exchange (ETDEWEB)

In a reactor environment, the surface of a limiter or wall is primarily determined by the mechanism of erosion and deposition of surface material. It should be possible to use pellet injection to reduce net erosion to zero everywhere if low-Z materials are used for the surface. Erosion rates can, in general, be minimized by large area limiters and high plasma temperatures, which transmit power to the walls with less sputtering. Under ideal steady state conditions the wall surface is dominated by metallurgical effects in the wall.

1980-01-01

219

Complex Abdominal Wall Repair  

Medline Plus

... presentation will be archived on the OR-Live website. 00:46:02 ANNOUNCER: This has been a ...

221

FEA Analysis of AP-0 Target Hall Collection Lens (Current Design)  

Energy Technology Data Exchange (ETDEWEB)

The AP-0 Target Hall Collection Lens is a pulsed device which focuses anti-protons just downstream of the Target. Since the angles at which the anti-protons depart the Target can be quite large, a very high focusing strength is required to maximize anti-proton capture into the downstream Debuncher Ring. The current design of the Collection Lens was designed to operate with a focusing gradient of 1,000 T/m. However, multiple failures of early devices resulted in lowering the normal operating gradient to about 750 T/m. At this gradient, the Lens design fares much better, lasting several million pulses, but ultimately still fails. A Finite Element Analysis (FEA) has been performed on this Collection Lens design to help determine the cause and/or nature of the failures. The Collection Lens magnetic field is created by passing high current through a central conductor cylinder. A uniform current distribution through the cylinder will create a tangential or azimuthal magnetic field that ...

2001-06-22

222

Virasoro algebra action on integrable hierarchies and Virasoro contraints in matrix models  

International Nuclear Information System (INIS)

The action of the Virasoro algebra on integrable hierarchies of non-linear equations and on related objects ('Schroedinger' differential operators) is investigated. The method consists in pushing forward the Virasoro action to the wave function of a hierarchy, and then reconstructing its action on the dressing and Lax operators. This formulation allows one to observe a number of suggestive similarities between the structures involved in the description of the Virasoro algebra on the hierarchies and the structure of conformal field theory on the world-sheet. This includes, in particular, an 'off-shell' hierarchy version of operator products and of the Cauchy kernel. In relation to matrix models, which have been observed to be effectively described by integrable hierarchies subjected to Virasoro constraints, I propose to define general Virasoro-constrained hierarchies also in terms of dressing operators, ...

1991-12-01

223

Influence of surface heat flux ratio on heat transfer augmentation in square channels with parallel, crossed, and V-shaped angled ribs  

Science.gov (United States)

The paper investigates the effect of the wall heat flux ratio on the local heat transfer augmentation in a square channel with two opposite in-line ribbed walls for Reynolds numbers from 15,000 to 80,000. The square channel composed of 10 isolated copper sections has a length-to-hydraulic diameter ratio of 20. The rib height-to-hydraulic diameter ratio is 0.0625 and the rib pitch-to-height ratio equals 10. Six ribbed side to smooth side wall heat flux ratios are studied for four rib orientations. The results show that the ribbed side wall heat transfer augmentation increases with increasing ribbed side to smooth side wall heat flux ratios, but the reverse is true for the smooth side wall heat transfer augmentation. The average heat transfer augmentation of the ribbed side and smooth side wall decreases slightly with increasing ...

1992-10-01

224

CFD Analysis of a Dry Storage System for MACSTOR/KN-400  

International Nuclear Information System (INIS)

There are four nuclear power plants in operation at Wolsong and, annually, more than 5,000 assemblies of spent nuclear fuels are released from each plant. Thus the concrete silo type dry storage system was constructed from '90. However, after 2006, another dry storage facility is required to accept the all amount of spent nuclear fuels from the plants. Instead of the concrete silo type, MACSTOR/KN-400 was developed to store the CANDU spent nuclear fuel more densely. In this study, computational fluid dynamics (CFD) analysis of the MACSTOR/KN-400 model was performed to confirm the thermal integrity of the facility, especially for the concrete structure, using the commercial CFD code, FLUENT. The MACSTOR/KN-400 which has Thermal Insulation Panel (TIP) and IAEA Re-verification Pipe (RVP) was modeled and analyzed in the view point of the thermal integrity of the concrete structure.

2007-10-01

225

An Integrated Hydrologic Bayesian Multi-Model Combination Framework: Confronting Input, parameter and model structural uncertainty in Hydrologic Prediction  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new technique--Integrated Bayesian Uncertainty Estimator (IBUNE) to account for the major uncertainties of hydrologic rainfall-runoff predictions explicitly. The uncertainties from the input (forcing) data--mainly the precipitation observations and from the model parameters are reduced through a Monte Carlo Markov Chain (MCMC) scheme named Shuffled Complex Evolution Metropolis (SCEM) algorithm which has been extended to include a precipitation error model. Afterwards, the Bayesian Model Averaging (BMA) scheme is employed to further improve the prediction skill and uncertainty estimation using multiple model output. A series of case studies using three rainfall-runoff models to predict the streamflow in the Leaf River basin, Mississippi are used to examine the necessity and usefulness of this technique. The results suggests that ignoring either input forcings error or model structural uncertainty will lead to unrealistic ...

2006-05-05

226

A two-arm gaseous spiral in the inner 200 pc of the early-type galaxy NGC 2974: signature of an inner bar  

CERN Document Server

TIGER integral-field spectrography and HST/WFPC2 imaging of the E3 galaxy NGC 2974 are used to derive the kinematics of the stellar and ionized gas components in its central 500 pc. We derive a numerical two-integral distribution function from a MGE mass model using the HQ formalism. The TIGER as well as published long-slit stellar kinematics are well fitted with this self-consistent model, requiring neither the addition of a significant mass contribution from a hidden disc structure, nor the presence of a central dark mass. The data reveal the presence of a striking, highly contrasted, two-arm gaseous spiral structure within a radius of ~200 pc, corresponding to a total mass of 6.8x10^4 Msun of ionized gas. We use a deconvolved TIGER datacube to probe its kinematics at a resolution of about 0.35 arcsec. Strong departures from circular motions are observed, as well as high velocity dispersion values on ...

2003-01-01

227

Climate change in the Cairns and Great Barrier Reef region. Scope and Focus for an Integrated Assessment  

International Nuclear Information System (INIS)

This study was undertaken to determine the scope and focus for an integrated assessment of climate change impacts on, and adaptation options for, the Cairns Great Barrier Reef (CGBR) region. To achieve this, the authors employed both technical expertise and regional stakeholder input. This document describes the study objectives and the process used to meet these objectives, and provides an overview of the CGBR region, the views of technical experts on potential climate change impacts, stakeholder prioritisation of impacts and adaptation options, a list of perceived knowledge gaps, and a recommended structure for a future integrated assessment in the region. The aim of the study was to determine the scope and focus for an integrated regional assessment of climate change impacts on, and adaptation options for, the CGBR region. The key objectives of the study were: Define and describe the study region; ...

228

Involvement of the chest and abdominal wall as a rare manifestation in Hodgkin's disease  

Energy Technology Data Exchange (ETDEWEB)

Radiological findings of chest and abdominal wall involvement in Hodgkin's disease are reported. This manifestation was diagnosed in one patient in the primary staging and in two patients during the course of the disease. Typical radiological findings are soft tissue masses in the chest and abdominal wall, in two cases with continous tumor growth of enlarged mediastinal lymphnodes into the anterior chest wall. The axial computed tomography is the best method to evaluate the extent of chest and abdominal wall involvement in Hodgkin's disease.

1983-03-01

229

Two-Loop Virtual Corrections to Drell-Yan Production at order alpha_s alpha^3  

CERN Document Server

The Drell-Yan mechanism for the production of lepton pairs is one of the most basic processes for physics studies at hadron colliders. It is therefore important to have accurate theoretical predictions. In this work we compute the two-loop virtual mixed QCD x QED corrections to Drell-Yan production. We evaluate the Feynman diagrams by decomposing the amplitudes into a set of known master integrals and their coefficients, which allows us to derive an analytical result. We also perform a detailed study of the ultraviolet and infrared structure of the two-loop amplitude and the corresponding poles in epsilon.

2011-01-01

230

Proceedings of the third international conference on containment design and operation. v.1  

International Nuclear Information System (INIS)

The second international conference on containment design and operation included sessions on the following topics: performance and regulatory requirements; radionuclide behaviour; severe accident design and analysis; operation, maintenance, leaking and aging of containment systems; thermal hydraulic behaviour of containment systems; hydrogen mixing and mitigation; design methods and concepts; code validation; structural analysis and response tests; passive safety systems; aerosol behaviour; containment reliability, integrity, and risk assessment; hydrogen deflagration and detonation. Due prominence was given to CANDU and other PHWR reactors. The individual papers have been abstracted separately.

1994-10-19

231

On the structure of locally Lipschitz minimax solutions of the Hamilton-Jacobi-Bellman equation in terms of classical characteristics  

British Library Electronic Table of Contents (United Kingdom)

Necessary and sufficient conditions for a minimax solution to the Cauchy problem for the Hamilton-Jacobi-Bellman equation are obtained as viability conditions for classical characteristics inside the graph of this solution. Using this property, a representative formula for a one-dimensional conservation law in terms of classical characteristics is derived. An estimate of the numerical integration of the characteristic system is presented and errors of numerical realizations of representative formulas are determined for the conservation law and its potential equal to the minimax solution of the Hamilton-Jacobi-Bellman equation.

2010-01-01

232

Nuclear reactor with external structure cooling by natural convection  

International Nuclear Information System (INIS)

The invention concerns an integrated nuclear reactor comprising natural convection cooling of the supporting skirt on which rests the shield closing the reactor vessel. Cooling is achieved by making the air circulate from the bottom to the top around the skirt and removing this air by a stack. The air can be atmospheric air or air taken from the low parts of the reactor. In the latter case, the stack emerges near a metal roof releasing its heat to the atmosphere by radiation, the air then dropping to the low parts. Application to fast nuclear reactors.

233

Integrating decision support tools and environmental information systems: a case study on the Province of Milan  

International Nuclear Information System (INIS)

The paper demonstrates an application of advanced decision support tools within the framework of the environmental information system of the Province of Milan. These tools include environmental simulation models, multi criteria analysis, risk analysis and environmental accounting for marketable emission permits. After describing the general structure of the system, three demonstrational case studies are introduced concerning: groundwater pollution management; atmospheric pollution management; urban environmental quality perception and management. In the conclusion, potential use of tools like the ones implemented by the province of Milan within the framework of Local Agenda 21 processes is recalled.

2006-03-01

234

High capacity heavy media processing  

Energy Technology Data Exchange (ETDEWEB)

Pittston Coal Company recognized the potential economic benefit of improving process efficiency with increased capacity at it`s U.K. No. 1 Coal Preparation Plant. Accordingly, extensive research, both domestically and internationally, was conducted to select the appropriate technologies to achieve the desired circuit in the most cost effective manner while, at the same time, sacrificing neither structural integrity nor process performance. Large diameter heavy media cyclone technology was combined with highly efficient banana type screens and improved high intensity magnetic separators to create a coordinated process circuit that provided high efficiency at very high capacities in an economically attractive package.

1996-12-31

235

Energy production: institutional and legislative scenario  

Energy Technology Data Exchange (ETDEWEB)

Brief comments are given on the evolution of the institutional nature of ENEL (Italian Electricity Board) as it relates to the framework of legislation for the nationalization of the utility in December, 1962. Special attention is given to the development of legislative criteria to allow the creation of a rate structure, in the case of autoproduction by industry, that would stimulate national economic growth. A discussion is also made of the changing role of ENEL as it responds to the planning objectives cited in the Italian National Energy Plan which calls for a more integrated effort by the regional governments and the Electricity Board in the management of natural resources.

1989-05-01

236

Design of self-tuning PID power system stabilizer for multimachine power systems  

Energy Technology Data Exchange (ETDEWEB)

A self-tuning PID (proportional-integral-derivative) power system stabilizer (PSS) is presented for improving the dynamic stability of a multimachine power system over a wide range of operating conditions. In order to maintain good damping characteristic when there is a drastic change in system operating condition, the gain settings are adapted in real time based on the continuously measured system inputs and outputs. The proposed self-tuning stabilizer has a decentralized structure and only local measurements within each generating units are required for the adaptation process. The effectiveness of the proposed stabilizer is demonstrated by an example.

1988-08-01

237

Cost-effectiveness of combustion turbines: recommendations for reliability, maintainability, supportability and maintenance requirements  

Energy Technology Data Exchange (ETDEWEB)

The profitability of combustion turbines intended for export is of extreme importance for Electricite de France. It is principally during the development phase of a project that one can ensure resect of two indissociable factors, essential to the per-kWh production cost: global operating costs and performance in terms of reliability and availability. The approach proposed here advocates the global acquisition of the installation and its logistic support. Generally applicable recommendations are given. They enable integrating in the future plant specifications all requirements relative to plant reliability, availability, maintainability and logistic support. They are structured according to type: expression of needs and management factors. (orig.) 4 refs.

1998-12-31

238

Calculating multileg one-loop processes. The case of gg{yields}t anti tgg  

Energy Technology Data Exchange (ETDEWEB)

This study is targeted to the NLO corrections of multileg processes, very important for the LHC. Starting from the construction of Feynman diagrams, the analytical reduction of general one-loop integrals to scalar master ones, the calculation of color structures, manipulation of spinor lines and other amplitude constituents and finally phase space point selection are obtained by use of a program producing Fortran code for numerical calculation of one-loop corrections for processes like gg{yields}t anti tgg. (orig.)

2010-05-15

239

An object oriented software bus  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a new approach to development of software for highly integrated software-hardware systems such as used for data acquisition and control. This approach, called the Object Oriented Software Bus (OSB), is a way to develop software according to a common specification similar to the way interface hardware has been developed since the advent of bus structures for minicomputers and microcomputers. Key concept of the OSB is extension of the common use of objects to support user interface and data analysis functions to the development of software objects that directly correspond to real- world hardware interfaces and modules.

1995-12-31

240

Alternative Loop Rings  

CERN Document Server

For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

1996-01-01

241

Road maps on research and development plans for water chemistry of nuclear power systems  

International Nuclear Information System (INIS)

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

2008-05-01

242

Repair of floating offshore units using bonded fibre composite materials  

British Library Electronic Table of Contents (United Kingdom)

On ships, tankers and similar vessels structural defects such as cracks and corrosion damage are typically repaired by welding. However, welding is unwanted hotwork on floating offshore units (FOUs) such as floating, production, storage and offloading (FPSO) and floating, storage and offloading (FSO) vessels because it requires shutdown of parts of the vessel thus resulting in expensive production delays. Bonded fibre composite material patch repairs can be used as an alternative to overcome the hazards of hotwork associated with welding. The patches are bonded over the defect and the integrity of the original structure is hence restored. The patch repair technology can also be utilised to provide upgrades, such as life extensions and higher design requirements. A recommended practice (RP)...

2009-01-01

243

How can supply networks increase firm value? A causal framework to structure the answer  

British Library Electronic Table of Contents (United Kingdom)

The recent literature in the field of supply chain management emphasizes the role of inter-organizational networks and the integration of vertical reproduction networks (supply chains) in particular as a key factor for value creation. However, the literature includes little empirical evidence. This situation suggests the need to appraise investments in such networks or supply chains carefully. How can a decision maker reliably assess the effect of investing in inter-organizational network arrangements on firm value? This article takes up this issue and suggests a framework consisting of five components to help answer the question. The task of the framework is to support the structuring and revelation of the causal chain between investments in the network on the one hand and the effect of t...

2009-01-01

244

E-commerce usage and business performance in the Malaysian tourism sector: empirical analysis  

British Library Electronic Table of Contents (United Kingdom)

Purpose - Based upon the E-VALUE model developed, this paper aims to investigate the impact of e-commerce usage on business performance in the tourism sector. Design/methodology/approach - A cross-sectional survey is carried out on 165 Malaysian firms involved in the tourism sector (hotels, resorts, and hospitals engaged in health tourism) through the use of a structured questionnaire. Findings - The structural equation modeling results indicate that technology competency, firm size, firm scope, web-technology investment, pressure intensity, and back-end usage have significant influence on e-commerce usage. Among these variables, back-end integration is found to function as a mediator. E-commerce experience (in years) is found to moderate the relationship between e-commerce usage and busin...

2009-01-01

245

Conceptual design of a low-temperature radiation-hard tracker detector  

CERN Document Server

Silicon sensors have about ten times improved radiation hardness around 130 K temperature, compared with the state-of-art sensors close to room temperature. This is based on the Lazarus effect studied by the RD39 Collaboration of CERN. Other benefits of low temperatures will also be discussed. We shall describe the conceptual design of low-mass detector modules cooled using two-phase flow of argon in miniature cooling pipes integrated in the module structure between the sensors and the readout hybrid circuit. The main engineering features of the cooling system and mechanical support structures are discussed, as well as the benefits arising from the operation of the tracker under cryogenic vacuum. 4 Refs.

2003-01-01

246

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

247

Aerodynamic and structural design of a solar-powered micro unmanned air vehicle  

Energy Technology Data Exchange (ETDEWEB)

The field of micro unmanned aerial vehicles ({mu}UAVs) has advanced rapidly in recent years. This paper studies the design and construction of a small solar-powered aircraft near the size range of current {theta}UAVs. A number of aspects of their design were analysed, including structural, aerodynamic and propulsion system considerations. The effect of small-scale, low Reynolds number aerodynamics was investigated, and the performance of a range of candidate aerofoils was compared. The integration of a solar power source into the aircraft system was considered a key design issue. Consequently, a number of aircraft configurations were examined, with the intention of optimising the application of solar power in a miniature aircraft. Investigation of improved system components suggests that a practical solar-powered aircraft in the size range below 500 mm maximum linear dimension should be viable given modest technological improvements. (Author)

2000-04-01

248

Development of a 3-D model for eddy current testing: application for fastened structures in aeronautics; Developpement d'un modele pour le controle non destructif par courants de Foucault de structures rivetees en aeronautique  

Energy Technology Data Exchange (ETDEWEB)

One of the Eddy Current Testing issues in aeronautics is the inspection of fastened structures to detect flaws nearby rivets which can grow because of mechanical stress. EADS and the CEA LIST have started a collaborative work with the support of the Ile-de-France Region to develop a simulation tool of EC fastened structures testing, integrated to the CIVA platform, aimed at conceiving testing methods, optimizing and qualifying it. The volume integral method using the Green dyadics formalism has been chosen in order to get a fast resolution of Maxwell equations. A first milestone was to build a simulation model of multilayer structures testing, thanks to the use of the multilayer Green dyads. Because of the rivet volume, 60 times bigger than the one of a typical flaw, a large number of discretization cells are needed. Therefore an iterative method has been developed in order to ...

2007-12-15

249

Structural acceptance criteria for the evaulation of existing double-shell waste storage tanks located at the Hanford site, Richland, Washington  

Energy Technology Data Exchange (ETDEWEB)

The structural acceptance criteria contained herein for the evaluation of existing underground double-shell waste storage tanks located at the Hanford Site is part of the Life Management/Aging Management Program of the Tank Waste Remediation System. The purpose of the overall life management program is to ensure that confinement of the waste is maintained over the required service life of the tanks. Characterization of the present condition of the tanks, understanding and characterization of potential degradation mechanisms, and development of tank structural acceptance criteria based on previous service and projected use are prerequisites to assessing tank integrity, to projecting the length of tank service, and to developing and applying prudent fixes or repairs. The criteria provided herein summarize the requirements for the analysis and structural qualification of the existing double-shell tanks for ...

1995-09-01

250

P-LIGA: 3D-integration of microstructures with curved surfaces by deep ion irradiation  

International Nuclear Information System (INIS)

Using the advantage that the projected range of ions in matter is sharply limited, a new technique for the production of three-dimensional microstructures has been developed. Based on the P-LIGA technique (Proton-Lithographie, Galvanoformung, Abformung) this process allows the generation of structures with surfaces of almost any shape having a root mean square roughness of about #lambda#/50 for visible light wavelengths. An ion beam with diameters between 2 and 50 #mu#m is directly writing the structures and the shape is varied by geometrical manipulation of the sample in three axes during the exposure. Practically, structures have been written using protons with an energy of 1.8 MeV in a provisional experimental setup with beam diameters of 10 and 50 #mu#m, respectively. After irradiation, the parts exposed were dissolved in a liquid developer without affecting the nonirradiated parts. The shape and the rms roughness of ...

1998-04-01

251

Dynamic security assessment in electric power systems  

Energy Technology Data Exchange (ETDEWEB)

A new approach to dynamic security assessment in electric power systems is proposed. A power system is modeled as a dynamical system with random variable structure. Structural variations are caused by primary and secondary events. Primary events are state-independent disturbances representing line and unit faults and load changes and are modeled by random jump processes. Secondary events that represent forced line and unit outages and load sheddings are modeled through an aggregate representation of the protection system as random processes whose change in time corresponds to the crossing of switching surfaces by the state process. These switching surfaces are defined by the setting of the protective relays. Commensurate with this model a three-state decomposition of the operating conditions into normal, emergency, and partial load operating states is suggested. Transitions between these states are described in terms of set-valued mappings in ...

1983-01-01

252

An effective method for the linearization of nodal stress components to apply ASME criteria  

Energy Technology Data Exchange (ETDEWEB)

The code of ASME Sec. III prescribes the general rules upon the design of a NSSS (nuclear steam supply system). The code provides further flexibility to the design of the nuclear structures by introducing a design by analysis concept. But it still preserves the conservatisms in design works by imposing strict failure mechanism and controlling material properties in use. A designer should prove the integrity of a structure under consideration by comparing the stress intensity, which was driven from the linearization of stress at concerning section, with the prescribed one. The recent development in computing system has enabled the commercial finite element programs to be a prevailing way to structural analysis field. But only few programs provide the procedure for stress linearization through the post-processing stage. Therefore, the simplified method which uses nodal stresses over the concerning section ...

2002-02-01

253

Field driven ferromagnetic phase evolution originating from the domain boundaries in antiferromagnetically coupled perpendicular anitsotropy films  

Energy Technology Data Exchange (ETDEWEB)

Strong perpendicular anisotropy systems consisting of Co/Pt multilayer stacks that are antiferromagnetically coupled via thin Ru or NiO layers have been used as model systems to study the competition between local interlayer exchange and long-range dipolar interactions [1,2]. Magnetic Force Microscopy (MFM) studies of such systems reveal complex magnetic configurations with a mix of antiferromagnetic (AF) and ferromagnetic (FM) phases. However, MFM allows detecting surface stray fields only and can interact strongly with the magnetic structure of the sample, thus altering the original domain configuration of interest [3,4]. In the current study they combine magnetometry and state-of-the-art soft X-ray transmission microscopy (MXTM) to investigate the external field driven FM phase evolution originating from the domain boundaries in such antiferromagnetically coupled perpendicular anisotropy films. MXTM allows directly imaging the perpendicular component of the ...

2008-05-01

254

Computed tomography of the mediastinal lesion  

Energy Technology Data Exchange (ETDEWEB)

Authors retrospectively analyzed the CT findings of mediastinal lesions in surgically or clinically confirmed 37 cases at Kosin Medical College during recent 4 years from September 1979 to August 1983. 1. Among 37 caes, malignant lymphoma were 7 cases, thymoma and vascular lesion or anomaly were 5 cases respectively, benign teratoma and tuberculous mediastinal lymphadenitis and neurogenic tumor were 4 cases respectively, pericardial cyst were 2 cases, bronchogenic cyst, non-specific cyst, pancreatic pseudocyst, mesothelioma, Bochdalek hernia was 1 case respectively. 2. The sex ratio between male and female was about 1 : 1 and the majority of the patients with malignant lymphoma and teratoma was under 20 years old. 3. CT findings of the each mediastinal lesion. 1) Primary mediastinal malignant lymphoma. (1) A large, matted, continuous and midline-crossing mass was observed in the superior and the anterior mediastinums in all cases. (2) In 3 cases, irregular lower densities were seen in ...

1984-09-15

255

Target area chamber system design for the National Ignition Facility  

International Nuclear Information System (INIS)

The National Ignition Facility (NIF) is a proposed Department of Energy facility which will contribute to the resolution of important Defense Program and inertial fusion energy issues for energy production in the future. The NIF will consist of a laser system with 192 independent beamlets transported to a target chamber. The target chamber is a multi-purpose structure that provides the interface between the target and the laser optics. The chamber must be capable of achieving moderate vacuum levels in reasonable times; it must remain dimensionally stable within micron tolerances, provide support for the optics, diagnostics, and target positioner; it must minimize the debris from the x-ray and laser light environments; and it must be capable of supporting external neutron shielding. The chamber must also be fabricated from a low neutron activation material. The fusion reaction in the target gives off neutrons, x-ray and gamma rays. The x-rays and gamma rays interact ...

1994-06-19

256

Probabilistic leak before break evaluation of straight pipes of primary heat transport piping of Tarapur-3 and 4 NPP  

International Nuclear Information System (INIS)

Piping systems transporting high-pressure fluid will release a large amount of energy, leading to whipping of the broken pipe as well as impingement of the ejecting fluids on adjacent structures if they fracture unstably. Postulation of such an event in design of piping systems in nuclear power plants often requires various counter measures such as installation of pipe whip restraints or jet impingement shields to prevent such damage. One of the approaches to justify exclusion of unstable fracture from the design conditions is leak-before-break (LBB) analysis. In order to demonstrate LBB behavior, it is necessary to prove that in the presence of a part-through wall flaw in the pipe, this flaw will not grow through the wall under fatigue loading and is stable (level 2 LBB) and that the leak of fluid through the penetration is detected by leak detection systems before unstable fracture occurs (level 3 LBB). If this can be ...

2006-11-01

257

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography  

International Nuclear Information System (INIS)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T_1-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was ...

2003-09-01

258

A task-based usage strategy for control centre wall displays  

Energy Technology Data Exchange (ETDEWEB)

This paper summarizes the findings from an exploratory definition of a usage strategy for multiple control centre wall displays in CANDU nuclear power plants. Wall displays are defined as large sized, vertically oriented display surfaces that may be positioned in various locations about a control room to support user information needs. The paper begins by discussing the need for a usage strategy for all control room information resources, and then reviews the history in wall display implementation and usage in nuclear power plant control rooms. The balance of the paper discusses the approach used in characterization and review of control room task information needs and definition of a wall display usage strategy. The paper concludes by outlining some of the possible impacts on future control room design and operations that the introduction of wall displays may imply. (author)

2005-07-01

259

Ground penetrating radar and direct current resistivity evaluation of the desiccation test cap, Savannah River Site  

Energy Technology Data Exchange (ETDEWEB)

The Savannah River Site (SRS) has a variety of waste units that may be temporarily or permanently stabilized by closure using an impermeable cover to prevent groundwater infiltration. The placement of an engineered kaolin clay layer over a waste unit is an accepted and economical technique for providing an impermeable cover but the long term stability and integrity of the clay in non-arid conditions is unknown. A simulated kaolin cap has been constructed at the SRA adjacent to the Burial Ground Complex. The cap is designed to evaluate the effects of desiccation on clay integrity, therefore half of the cap is covered with native soil to prevent drying, while the remainder of the cap is exposed. Measurements of the continuing impermeability of a clay cap are difficult because intrusive techniques may locally compromise the structure. Point measurements made to evaluate clay integrity, such as those from ...

1996-04-01

260

GASVOL 18'' gas pipeline - risk based inspection study  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a risk based approach and inspection planning as part of the Pipeline Integrity Management (PIM) system for the 95.5 km long 18'' GASVOL gas pipeline in the South eastern region of Brazil transporting circa 5 000 000 m3 dry gas per day. Pipeline systems can be subject to several degradation mechanisms and inspection and monitoring are used to ensure system integrity. Modern pipeline regulations and codes are normally based on a core safety or risk philosophy. The detailed design requirements presented in design codes are practical interpretations established so as to fulfill these core objectives. A given pipeline, designed, constructed and installed according to a pipeline code is therefore the realization of a structure, which, along its whole length, meets the applicable safety objectives of that code. The main objective of Pipeline Integrity Management (PIM) is ...

2003-07-01

261

Damping of toroidal ion temperature gradient modes  

Energy Technology Data Exchange (ETDEWEB)

The temporal evolution of linear toroidal ion temperature gradient (ITG) modes is studied based on a kinetic integral equation including an initial condition. It is shown how to evaluate the analytic continuation of the integral kernel as a function of a complex-valued frequency, which is useful for analytical and numerical calculations of the asymptotic damping behavior of the ITG mode. In the presence of the toroidal {nabla}B-curvature drift, the temporal dependence of the density and potential perturbations consists of normal modes and a continuum mode, which correspond to contributions from poles and from an integral along a branch cut, respectively, of the Laplace-transformed potential function of the complex-valued frequency. The normal modes have exponential time dependence with frequencies and growth rates determined by the dispersion relation while the continuum mode, which has a ballooning ...

1999-04-01

262

PSAD-a monitoring and aid to diagnosis system participating in saving on maintenance and operation costs and for plant life extension  

International Nuclear Information System (INIS)

Monitoring nuclear plants components enable to save on operation and maintenance costs by reducing incidents gravity and casual plant stoppages thank to early detection and fast diagnosis. Improving the knowledge of the behaviour of the plant will also allow to optimize maintenance and to increase plant life. In order to improve monitoring and diagnosis capabilities in nuclear power plants. Electricite de France (EDF) is extending the existing data processing chains towards automatic aided interpretation and diagnosis. Therefore, EDF has designed an integrated monitoring and diagnosis assistance system: PSAD-Poste de Surveillance et d'Aide au Diagnostic, including several monitoring functions of the main components. It integrates on-line monitoring, off-line diagnosis and knowledge based systems. PSAD stations provide homogeneous aids to diagnosis which enable plant personnel to pinpoint the mechanical behaviour of plant equipment. The ...

1997-04-14

263

Merger control in the energy sector. An empirical investigation for the Federal Republic of Germany; Fusionskontrolle in der leitungsgebundenen Energiewirtschaft. Eine empirische Untersuchung fuer Deutschland  

Energy Technology Data Exchange (ETDEWEB)

In 1998, EU legislation initiated a liberalisation process among European energy markets. The process of market opening has significantly changed the functioning of the markets and the competition conditions of the energy sector. At the same time, the industry witnessed a surge of mergers and far-reaching changes in the structure of German electricity and natural gas markets occurred. Against this background, the doctoral thesis at hand surveys the merger activities in the energy sector as well as the merger control policy of the German Federal Cartel Office during the first years of liberalisation. The study starts with a portrayal of the institutional framework of the German merger control regime and a survey of the relevant economic literature on horizontal and vertical mergers. Subsequent to the legal and theoretical considerations, the merger activities and the merger control policy of the German Federal Cartel Office are investigated empirically. The data set ...

2008-11-06

264

Proposed Network Security Policy for Integrated Tactical ...  

Science.gov (United States)

... MTR 93B0000095 Proposed Network Security Policy for Integrated Tactical Warning ... Proposed Network security Policy for Integrated Tactical ...

1993-09-01

265

Maintaining Tank and Infantry Integration Training  

Science.gov (United States)

Page 1. Maintaining Tank and Infantry Integration Training ... 4. TITLE AND SUBTITLE Maintaining Tank and Infantry Integration Training 5a. ...

2005-01-11

266

Computer aided research system its framework and scopes. Kenkyu kaihatsu shien system wo kangaeru  

Energy Technology Data Exchange (ETDEWEB)

Discussions were given on the current status of research systems and problems that occur in structuring the systems. The purpose is to improve efficiency and quality of the research flows, that is to better arrange the research infrastructures. Among the researches, the developmental researches of products and production techniques constitute the important factor of an integrated production system. Input information and output information must be determined in each developmental process, and the ways of internal processing must be arranged and structured. The basic proposition for structuring an aid system is to clarify what material development this system can bring about, what scenario can be drawn for the material development as its result, and what element technology is required for that scenario in what form and at what level. Discussions are required on the kinds of data base, the models of ...

1991-07-05

267

Application of a finite element method to leak before break (LBB) of a heat exchanger  

International Nuclear Information System (INIS)

The leak before break (LBB) concept is difficult to apply to a structure with a thin tube that is immersed in a water environment. A heat exchanger in a nuclear power plant is such a structure. The present paper addresses an application of the LBB concept to a heat exchanger in a nuclear power plant. The minimum leaked coolant amount containing the radioactive material which can activate the radiation detector device installed near the heat exchanger is assumed. The postulated initial flaw size that cannot grow to the critical flaw size within the time period to activate the radiation detector is justified. In this case, the radiation detector can activate the warning signal caused by coolant leakage from initially postulated flaws of the heat exchanger. The nuclear plant can safely shutdown when this occurs. Since the postulated initial flaw size can not grow to the critical flaw size, the structural ...

2003-08-17

268

Antenna organization in green photosynthetic bacteria. Progress report, March 1986--February 1987  

Energy Technology Data Exchange (ETDEWEB)

This project is concerned with the structure and function of the unique antenna system found in the green photosynthetic bacteria. The antenna system in these organisms is contained within a vesicle known as a chlorosome, which is attached to the cytoplasmic side of the cell membrane. Additional antenna pigments and reaction centers are contained in integral membrane proteins. Energy absorbed by the bacteriochlorophyll c (BChl c) pigments in the chlorosome is transferred via a ``baseplate`` array of BChl a antenna pigments into the membrane and to the reaction center. This system is similar in some respects to the phycobilisome antenna system found in cyanobacteria and some types of algae, in that a membrane-associated structure absorbs light and transfers it to the membrane where conversion to chemical energy takes place. However, the overall structure, the type of pigments utilized and the nature of ...

1987-12-31

269

Ammonia synthesis and ER-MCFC-technology - a profitable combination?  

Energy Technology Data Exchange (ETDEWEB)

Similar to stand-alone ER-MCFC power systems industrial ammonia production facilities include hydrogen-rich synthesis-gas production. Therefore, integration of ER-MCFC stacks in a conventional industrial ammonia plant was investigated. By preliminary process design calculations three promising process structures were evaluated: (1) ER-MCFC is fed by the ammonia plant`s steam-reformer; anode off-gas to firing (2) similar to structure 1; in this case the anode off-gas is redirected to the ammonia process (3) ER-MCFC is fed by ammonia-synthesis purge gas The results indicate that for options 1 and 3 a return-on-investment for the ER-MCFC of around 8% is achievable at a stack cost of $250/kW and a revenue of 7c/kWh. Option 2 is not profitable, because of the associated reduction in ammonia production. The degree of hydrogen-utilization in the ER-MCFC to be selected for maximum profit varies with the process ...

1996-12-31

270

Studies on localization of calcitonin gene-related peptide (CGRP) in the thyroid-parathyroid complex.  

Science.gov (United States)

Calcitonin gene-related peptide (CGRP) was localized by an immunocytochemical technique in the thyroid-parathyroid complexes of rat, guinea pig, rabbit, and in normal human thyroids and parathyroids. Human medullary carcinomas and parathyroid adenomas were also studied. In man and all animal species examined CGRP was present in the parafollicular cell, however, in guinea pigs only in small amounts. Except in rabbits, presence of CGRP was demonstrated in nerves of the thyroid and parathyroid capsule as well as in the nerve fibers of the capsular blood vessels. In the thyroid of guinea pigs CGRP was also noted in nerve fibers and in blood vessel walls between follicles. CGRP was also present in the parathyroid glands of rat and man, in nerve fibers localized between parathyroid cells. In rabbit the parafollicular cells between parathyroid cells also expressed CGRP immunoreactivity. No CGRP was noted in the parathyroids of the guinea pig. The proximity of parathyroid ...

1987-01-01

271

Recent increased use of polybutylene terephthalate (PBT) resin in automotive field. Jidosha bun prime ya de kinnen kakudai shimesu PBT jushi  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces marketability and parts application of PBT in the automotive field. Based on the pursuits in automobiles of weight reduction as measures to improve engine performance, drive performance, and fuel consumption, as well as trends of higher class car orientation, market expansion is expected on engineering resins including PBT. Adoption of PBT/polycarbonate (PC)-based alloy resins is on increase for use in external car parts because of the chemical resistance in PBT, low-temperature shock resistance and appearance of PC. Substitution from Nylon resin in connector application is progressing rapidly because of problems in dimensional stability and compound noise. Air bag sensor parts need to be free of maloperation due to contamination and corrosion in metal contacts caused from gases generated from formed parts, hence development of resins of low gas generation grade is wanted. Valves for exhaust control require high-temperature rigidity, dimensional stability, ...

1992-06-18

272

Pre-transitional disk nature of the AB Aur disk  

CERN Document Server

The disk around AB Aur was imaged and resolved at 24.6\\,$\\mu$m using the Cooled Mid-Infrared Camera and Spectrometer on the 8.2m Subaru Telescope. The gaussian full-width at half-maximum of the source size is estimated to be 90 $\\pm$ 6 AU, indicating that the disk extends further out at 24.6\\,$\\mu$m than at shorter wavelengths. In order to interpret the extended 24.6\\,$\\mu$m image, we consider a disk with a reduced surface density within a boundary radius $R_c$, which is motivated by radio observations that suggest a reduced inner region within about 100 AU from the star. Introducing the surface density reduction factor $f_c$ for the inner disk, we determine that the best match with the observed radial intensity profile at 24.6\\,$\\mu$m is achieved with $R_c$=88 AU and $f_c$=0.01. We suggest that the extended emission at 24.6\\,$\\mu$m is due to the enhanced emission from a wall-like structure at the boundary radius (the inner edge of ...

2010-01-01

273

On important matters (fire protection) related to No. 3 plant in the Hamaoka Nuclear Power Station, Chubu Electric Power Co., Inc., No. 2 plant in the Tsuruga Power Station, Japan Atomic Power Co., and No. 2 plant in the Sendai Nuclear Power Station, Kyushu Electric Power Co., Inc  

International Nuclear Information System (INIS)

The Nuclear Safety Commission acknowledged the policy of the Agency of Natural Resources and Energy to cope with these important matters on August 8, 1984. The main contents of the investigation and deliberation were as follows, As to the prevention of the occurrence of fires, the prevention of the leak and spread of inflammable liquid and gas, the installation of protective relays and so on, the use of incombustible materials and aseismatic design and the installation of lightning arresters. As to the detection of fires and fire fighting, the proper selection and arrangement of fire detectors and extinguishers, the extinguishers which do not harm the safety function of structures and equipment, and the extinguishers which are not affected by natural phenomena. As to the reduction of the effect of fires, the proper installation of fire walls and extinguishers, and the high temperature shut off of nuclear reactors which is never hampered by any ...

1985-01-01

274

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

275

Morphology of wood species affecting wood-thermoplastic interaction: microstructure and mechanical adhesion  

Scientific Electronic Library Online (English)

Abstract in english The main objective of the research presented here is to relate anatomical features of wood species that affect the interactions between polymeric phases and performance of wood plastic composites (WPC). These interactions are related to the probable interlocking volume and surface area for stress transfer in a WPC. Composites were produced from different wood species and analyzed using SEM (scanning electron microscopy). Results showed that wood species with high interfac (more) ial areas may increase mechanical interlocking, reflected in the viscous constant of the Maxwell model. A complicating factor is that the relation of cell wall thickness-lumen diameter and the interconnectivity between wood cells in a wood, affect the potential for cell collapse. When wood cells collapse, the penetration of the thermoplastic into the wood structure is almost always ceased. The collapse of wood cells during extrusion-injection molding ...

2009-01-01

276

Irradiation hardening and loss of ductility of type 316L(N) stainless steel plate material due to neutron-irradiation  

International Nuclear Information System (INIS)

Type 316 stainless steel is the primary candidate austenitic structural material for fusion first wall constructions. Here, type 316L(N) stainless steel plate material has been irradiated up to 10 dpa at temperatures of 80, 225, 325, and 425 C in the High Flux Reactor (HFR) of Petten. Tensile tests have been performed in the temperature range from RT to 575 C at a conventional strain rate of 5 x 10"-"4 s"-"1. The results of the tensile tests are analyzed in terms of irradiation hardening and loss of ductility due to irradiation. Tensile properties saturate in the early stage (within 0.65 dpa) at the lowest applied irradiation temperature. It is indicated that the most severe degradation of tensile ductility occurs in the temperature range of 275 to 350 C. Comparison with literature data revealed a large scatter in irradiation hardening at irradiation temperatures above 325 C.

1994-06-20

277

Heat transfer augmentation in a rectangular channel with a vee-shaped vortex generator  

International Nuclear Information System (INIS)

The unsteady flow and heat transfer are simulated using LES and DNS for a channel with two angled ribs as a vee-shaped vortex generator to augment heat transfer. The vortex generators are attached on the bottom wall of the channel and their angles in respect to the main flow are between 10"o and 30"o. The Prandtl number is 0.71 and the Reynolds numbers based on the inflow velocity and the height of channel are from 200 to 2000. Based on the results of this work, the variations of the Nusselt number, pressure coefficient, bulk temperature, friction factor and Colburn factor with the Reynolds numbers and the incidence angles are provided. The relation between the key parameters of the velocity (friction factor f) and thermal (Colburn factor J) boundary layers is calculated for all cases and their values are compared with the predicted values by the Chilton-Colburn analogy. A comparison between the DNS and LES results is performed and it is found that relatively ...

2007-04-01

278

Hardness and defect structures in EC316LN austenitic alloy irradiated under a simulated spallation neutron source environment using triple ion-beams  

Energy Technology Data Exchange (ETDEWEB)

For an assessment of the future US spallation neutron source (SNS) target performance, radiation induced hardening and microstructural evolution were investigated as a function of ion dose for EC316LN stainless steel. Irradiation was carried out using 3.5 MeV Fe{sup +}, 360 keV He{sup +}, and 180 keV H{sup +} simultaneous ion-beams at 200 deg. C to simulate the damage, He and H production in the SNS target vessel wall. At low dose (< 1 dpa), the predominant defects were black dots whose number density saturated rapidly within a few dpa. This was followed by the evolution of interstitial loops whose number density saturated below 15 dpa. Although He-bubbles were not visible, severely scalloped loops suggested that the implanted He/H atoms existed in the form of small clusters. Comparison with reported neutron irradiation data showed that hardening and ductility loss occurred mostly in the black dot regime (< 1 dpa), but that good ductility (>20% ...

2000-04-01

279

Hardness and defect structures in EC316LN austenitic alloy irradiated under a simulated spallation neutron source environment using triple ion-beams  

International Nuclear Information System (INIS)

For an assessment of the future US spallation neutron source (SNS) target performance, radiation induced hardening and microstructural evolution were investigated as a function of ion dose for EC316LN stainless steel. Irradiation was carried out using 3.5 MeV Fe"+, 360 keV He"+, and 180 keV H"+ simultaneous ion-beams at 200 deg. C to simulate the damage, He and H production in the SNS target vessel wall. At low dose (< 1 dpa), the predominant defects were black dots whose number density saturated rapidly within a few dpa. This was followed by the evolution of interstitial loops whose number density saturated below 15 dpa. Although He-bubbles were not visible, severely scalloped loops suggested that the implanted He/H atoms existed in the form of small clusters. Comparison with reported neutron irradiation data showed that hardening and ductility loss occurred mostly in the black dot regime (< 1 dpa), but that good ductility (>20% elongation) was maintained ...

2000-04-01

280

Evaluation on the formability of magnesium alloy, AZ31  

Energy Technology Data Exchange (ETDEWEB)

Magnesium is known to have poor formability at room temperature, mainly attributed to its hexagonal lattice structure. This paper presents the findings generated from development of warm forming to produce thin-walled magnesium components. Finite element analysis was conducted to evaluate the formability of the material and the simulated results were compared to the tensile results and product formability. Tensile tests were used to verify the formability of the sheet metal at difference temperatures. The process parameters considered in the feasibility study were forming temperature, in the range of 28 C to 300 C and magnesium sheet (AZ31B-H24) thickness, in the range of 0.4 mm to 1 mm. Magnesium hand phone covers of a thickness down to 0.4 mm have been successfully produced. The feasible forming temperature was found to be between 200 C and 250 C. Metallographic examination shows evident of recrystallisation when the magnesium sheets are ...

2003-07-01

281

Efficient modeling for pulsed activation in inertial fusion energy reactors  

International Nuclear Information System (INIS)

First structural wall material (FSW) materials in inertial fusion energy (IFE) power reactors will be irradiated under typical repetition rates of 1-10 Hz, for an operation time as long as the total reactor lifetime. The main objective of the present work is to determine whether a continuous-pulsed (CP) approach can be an efficient method in modeling the pulsed activation process for operating conditions of FSW materials. The accuracy and practicability of this method was investigated both analytically and (for reaction/decay chains of two and three nuclides) by computational simulation. It was found that CP modeling is an accurate and practical method for calculating the neutron-activation of FSW materials. Its use is recommended instead of the equivalent steady-state method or the exact pulsed modeling. Moreover, the applicability of this method to components of an IFE power plant subject to repetition rates lower than those of the FSW is ...

2000-11-01

282

Effect of V-shaped defects on structural and optical properties of AlGaN/InGaN multiple quantum wells  

International Nuclear Information System (INIS)

We have investigated the correlation between V-shaped defect formation and the optical properties of AlGaN/(In)GaN multiple quantum wells (MQWs) grown under different growth conditions and then demonstrated the characteristics of fabricated ultraviolet (UV) light emitting diodes (LEDs). From the temperature-dependent photoluminescence (PL) measurement, the internal quantum efficiency for 300 K was obtained as 43.6% for a sample with a low density of V-defects in a MQW and 13.7% for a sample with a high density of V-defects. The carrier lifetime based on the time resolved PL measurement at room temperature was 0.32 ns for a sample with a high density of V-defects and 1.26 ns for a sample with a low density of V-defects. And we also found that the density of V-defects affected the external quantum efficiency and wall plug efficiency of the fabricated UV LEDs. (fast track communication)

2008-07-07

283

Designing a healthy house - an overview  

Energy Technology Data Exchange (ETDEWEB)

There are certain factors to take into account when determining the suitability of a healthy house site. Power lines, agricultural spraying, vehicle exhaust, and industrial pollution are all potential sources of indoor air contamination. It is recommended that a environmental assessment be done to determine whether there are specific sources of contamination. Good drainage is required. The surrounding landscaping should be open and sunlit, and with low maintenance requirements. Decks and fences made from pressure-treated or chemical treated lumber should be avoided. One of the early decisions in the design process is the choice of the structural system. The key with all foundation types is to control moisture, whether from rain, from the ground, or the condensation of moisture from the air with cooling. The construction frame is sealed away from the occupants by the air/vapor barrier, so only in extreme cases is it essential to use alternatives to softwood lumber ...

1999-11-01

284

Walled-off pancreatic necrosis  

UK PubMed Central (United Kingdom)

Walled-off pancreatic necrosis (WOPN), formerly known as pancreatic abscess is a late complication of acute pancreatitis. It can be lethal, even though it is rare. This critical review provides an overview...Full Text Available

2010-04-14

285

Thermal energy considerations on solar cavity wall building  

Energy Technology Data Exchange (ETDEWEB)

The dwelling is equipped with solar collectors which heat the air circulating in the cavity walls and the space beneath the floors. The thermal aspects of such a building are described. Heat balance, losses, heating by the sun in different seasons are described. Different measures taken to reduce the energy losses are described.

1983-02-01

286

The Candida albicans Dse1 Protein Is Essential and Plays a Role in Cell Wall Rigidity, Biofilm Formation, and Virulence  

UK PubMed Central (United Kingdom)

The fungal pathogen Candida albicans is one of the leading causative agents of death in immunocompromised individuals. It harbors an arsenal of cell wall anchored factors that are implicated...Full Text Available

2011-01-01

287

Sealant tests to control radon emanation in a uranium mine. Open file report sep 79-dec 81  

International Nuclear Information System (INIS)

This report describes a field-test program to determine the effectiveness of a polymeric wall sealant to reduce the escape of naturally occurring radioactive gas radon from the walls of an underground uranium mine into the ventilation air.

288

Pretreatment with the gram-positive bacterial cell wall molecule peptidoglycan improves bacterial clearance and decreases inflammation and mortality in mice challenged with Pseudomonas aeruginosa  

UK PubMed Central (United Kingdom)

The objective of this study was to determine if inflammatory tolerance and enhancement of innate immune function could be induced by the gram-positive cell wall component peptidoglycan (PGN)....Full Text Available

2008-10-01

289

Poland's anomaly. Natural history and long-term results of chest wall reconstruction in 33 patients.  

UK PubMed Central (United Kingdom)

Poland's anomaly is an uncommon congenital aberration of the chest wall characterized by absence of the pectoralis major muscle and other nearby musculoskeletal components. In this series, a wide spectrum...Full Text Available

1988-12-01

290

Mapping strain exerted on blood vessel walls using deuterium double-quantum-filtered MRI  

UK PubMed Central (United Kingdom)

A technique is described for displaying distinct tissue layers of large blood vessel walls as well as measuring their mechanical strain. The technique is based on deuterium double-quantum-filtered (DQF)...Full Text Available

1998-04-14

291

Latent Tricuspid Valve Rupture after Motor Vehicle Accident and Routine Echocardiography in All Chest-Wall Traumas  

UK PubMed Central (United Kingdom)

Blunt chest-wall trauma is common; however, resultant tricuspid valve rupture is rare and can be subtle in its presentation. Transthoracic echocardiography plays a key role in diagnosis.Herein,...Full Text Available

2009-01-01

292

In-vivo coronary flow profiling based on biplane angiograms: influence of geometric simplifications on the three-dimensional reconstruction and wall shear stress calculation  

UK PubMed Central (United Kingdom)

BackgroundClinical studies suggest that local wall shear stress (WSS) patterns modulate the site and the progression of atherosclerotic lesions. Computational fluid dynamics (CFD)...Full Text Available

293

Ewing's sarcoma: a neuroectodermal tumor of the chest wall  

International Nuclear Information System (INIS)

Ewing's sarcoma is the second most common malignant bone tumor in children and young adults. It is most prevalent between the ages of 10 and 15 years. There are present two cases of Ewing's sarcoma of the chest wall. The clinical, radiological and pathological features are described and the therapeutic options are discussed. (Author)

294

Effects of Multivalent Cations on Cell Wall-Associated Acid Phosphatase Activity  

UK PubMed Central (United Kingdom)

Primary cell walls, free from cytoplasmic contamination were prepared from corn (Zea mays L.) roots and potato (Solanum tuberosum) tubers. After EDTA treatment, the...Full Text Available

1988-09-01

295

A Potential Elastohydrodynamic Origin of Load-Support and Coulomb-Like Friction in Lung/Chest Wall Lubrication  

UK PubMed Central (United Kingdom)

BackgroundDuring normal breathing, the mesothelial surfaces of the lung and chest wall slide relative to one another. Experimentally, the shear stresses induced by...Full Text Available

2008-10-01

296

A Model for Predicting Ionic Equilibrium Concentrations in Cell Walls 1  

UK PubMed Central (United Kingdom)

Purified cell walls were prepared from roots of Horse bean (Vicia faba L., var. minor) and Yellow Lupine (Lupinus luteus L.). Two methods were used:...Full Text Available

1981-08-01

297

A General Model of the Resistive Wall Instability in Linear Accelerators  

Energy Technology Data Exchange (ETDEWEB)

A general model for wakefield-generated instabilities in linear accelerators, originally developed for cumulative beam breakup [1], is applied to the resistive wall instability. The general solution for various bunch charge distributions and application to various accelerator configurations are presented.

2007-01-08

298

Single-Walled Carbon Nanotubes Targeted to the Tumor ...  

Science.gov (United States)

... 1981. Retention of diphenyls, terphenyls, phenylalkanes and fluorene on graphitized thermal carbon black. Chromatographia 14:510-514. ...

2009-09-01

300

Physical and Computational Investigation of the Wall Pressure ...  

Science.gov (United States)

... Although other authors had made cross-spectral density measurements, Corcos pointed to the importance of this function as indicative of the true ...

1990-04-26

302

The frequency map for billiards inside ellipsoids  

CERN Document Server

The billiard motion inside an ellipsoid $Q \\subset \\Rset^{n+1}$ is completely integrable. Its phase space is a symplectic manifold of dimension $2n$, which is mostly foliated with Liouville tori of dimension $n$. The motion on each Liouville torus becomes just a parallel translation with some frequency $\\omega$ that varies with the torus. Besides, any billiard trajectory inside $Q$ is tangent to $n$ caustics $Q_{\\lambda_1},...,Q_{\\lambda_n}$, so the caustic parameters $\\lambda=(\\lambda_1,...,\\lambda_n)$ are integrals of the billiard map. The frequency map $\\lambda \\mapsto \\omega$ is a key tool to understand the structure of periodic billiard trajectories. In principle, it is well-defined only for nonsingular values of the caustic parameters. We present four conjectures, fully supported by numerical experiments. The last one gives rise to some lower bounds on the periods. These bounds only depend on the type of ...

2010-01-01

303

Integration of advanced nuclear materials separation processes  

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project has examined the fundamental chemistry of plutonium that affects the integration of hydrothermal technology into nuclear materials processing operations. Chemical reactions in high temperature water allow new avenues for waste treatment and radionuclide separation.Successful implementation of hydrothermal technology offers the potential to effective treat many types of radioactive waste, reduce the storage hazards and disposal costs, and minimize the generation of secondary waste streams. The focus has been on the chemistry of plutonium(VI) in solution with carbonate since these are expected to be important species in the effluent from hydrothermal oxidation of Pu-containing organic wastes. The authors investigated the structure, solubility, and stability of the key plutonium complexes. ...

1998-12-31

304

Integrated EM & Thermal Simulations with Upgraded VORPAL Software  

Energy Technology Data Exchange (ETDEWEB)

Nuclear physics accelerators are powered by microwaves which must travel in waveguides between room-temperature sources and the cryogenic accelerator structures. The ohmic heat load from the microwaves is affected by the temperature-dependent surface resistance and in turn affects the cryogenic thermal conduction problem. Integrated EM & thermal analysis of this difficult non-linear problem is now possible with the VORPAL finite-difference time-domain simulation tool. We highlight thermal benchmarking work with a complex HOM feed-through geometry, done in collaboration with researchers at the Thomas Jefferson National Accelerator Laboratory, and discuss upcoming design studies with this emerging tool. This work is part of an effort to generalize the VORPAL framework to include generalized PDE capabilities, for wider multi-physics capabilities in the accelerator, vacuum electronics, plasma processing and fusion R&D fields, and we will ...

2011-03-01

305

Bar strengths in spiral galaxies estimated from 2MASS images  

CERN Document Server

Non-axisymmetric forces are presented for 107 spiral galaxies using the 2 Micron All Sky Survey (2MASS) images. We apply both Cartesian integration and a polar grid integration utilizing a limited number of azimuthal Fourier components of density. We found that bar strength is independent of the method used to evaluate the gravitational potential. However, the polar method is more suitable for weak and noisy images. Bar strength was found to be sensitive to the Hubble-type dependent scale height of the disk, which has been ignored in the previous studies. On the other hand, the method is rather insensitive to the vertical model of the disk, as long as a same vertical dispersion is assumed, or to the boxy/peanut shaped structure, studied in terms of non-constant vertical scale height along the disk. In the near-IR most galaxies in our sample show non-axisymmetric forces in some level, and 40 percent of them have bars in a ...

2002-01-01

306

Unsteady flow of an incompressible fluid in a horizontal porous medium with suction  

International Nuclear Information System (INIS)

A theoretical analysis of two-dimensional unsteady flow in a porous medium bounded by a horizontal wall is presented as a perturbation on a basic flow. It is assumed that the perturbation is occasioned by a sudden suction at the wall. Even for a highly permeable medium the characteristic Reynolds number in porous media flow is usually small and asymptotic solutions are developed by the Laplace transform technique. It is observed that the perturbed shear stress at the wall decays exponentially with time. (author). 5 refs.

2000-03-01

307

Thin Wall Iron Castings  

Energy Technology Data Exchange (ETDEWEB)

Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

2001-10-31

308

Survey of naturally radioactive level of some new type wall materials  

International Nuclear Information System (INIS)

Naturally occurring radioactive materials (NORM) in seven new type wall materials were surveyed. The radioactivity was determined with HPGe-#gamma# spectrometer. The red mud has the highest radioactivity concentration, followed by slag building blocks, fly-ash building blocks (bricks), gangue bricks and light weight board materials, gypsum blocks. Fly-ash and slag contain higher NORM, which contributes the major part of the radioactivity in new wall materials. (authors)

2006-09-01

309

Polymer depletion-induced slip near an interface  

Energy Technology Data Exchange (ETDEWEB)

A quantitative description is proposed for the depletion-induced slip thickness and velocity profile of a polymer solution near the wall-fluid interface in simple shear flow. The inhomogeneous polymer density profile at a flat wall is inserted into the equations of motion for the flow of a polymer solution near the flat wall. The theory is in quantitative agreement with simulation results. (letter to the editor)

2005-01-19

310

Modelling of the wall jet in a direct injection diesel engine  

Energy Technology Data Exchange (ETDEWEB)

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

1992-01-01

311

A device for assemblying a support string for an offshore drilling rig  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to simplify assembly and to reduce labor intensity. This is achieved by the fact that the assembly shaft is positioned in a hawser, while its wall which is turned towards the body of the installation is combined with the hawser wall, where a U shaped opening is made in the wall of the assembly shaft, along the edges of which there is a hermetically sealing device, while the bottom of the body of the offshore drilling rig is equipped with a rigid insert attached with the capability of adjoining it with the hermetically sealing device.

1983-01-01

314

Negative dimensional integration method and massive Feynman diagrams  

Energy Technology Data Exchange (ETDEWEB)

A constructive method is proposed to solve a class of massive Feynman integrals within the Negative Dimensional Integration Method. The results are compared with the ones given by known positive D models and expressed in terms of dimensionally and analytically regularized integrals 3 refs.

1997-12-31

316

Mediation of bone ingrowth in porous hydroxyapatite bone graft substitutes.  

Science.gov (United States)

Previous investigations have shown that both the early biological response and the mechanical properties of a porous hydroxyapatite bone graft substitute are highly sensitive to its pore structure. The objective of this study was to evaluate whether the pore structure continued to influence bone integration in the medium to long term. Two screened batches of porous hydroxyapatite (PHA) designated as batch A and batch B, with porosities of approximately 60 and 80%, respectively, were selected for this study and implanted for periods of 5, 13, and 26 weeks into the lower femur of New Zealand White rabbits. Histomorphometric analysis of the absolute volume of bone ingrowth within batch A and B implants from 5 to 26 weeks showed that the absolute volume of bone ingrowth was consistently lower in batch A (10-21%), compared to batch B implants (24-31%). However, when the volume of bone ingrowth was normalised for the available ...

2004-01-01

317

Dynamic-stiffness matrix of embedded and pile foundations by indirect boundary-element method  

Energy Technology Data Exchange (ETDEWEB)

The boundary-integral equation method is well suited for the calculation of the dynamic-stiffness matrix of foundations embedded in a layered visco-elastic halfspace (or a transmitting boundary of arbitrary shape), which represents an unbounded domain. It also allows pile groups to be analyzed, taking pile-soil-pile interaction into account. The discretization of this boundary-element method is restricted to the structure-soil interface. All trial functions satisfy exactly the field equations and the radiation condition at infinity. In the indirect boundary-element method distributed source loads of initially unknown intensities act on a source line located in the excavated part of the soil and are determined such that the prescribed boundary conditions on the structure-soil interface are satisfied in an average sense. In the two-dimensional case the variables are expanded in a Fourier integral in the ...

1984-08-01

318

System integration of pattern recognition, adaptive aided, upper limb prostheses  

Science.gov (United States)

The requirements for successful integration of a computer aided control system for multi degree of

1975-01-01

319

Integrating phytotechnologies with energy crop production for biofuels  

Science.gov (United States)

Integrating phytotechnologies with energy crop production for biofuels, bioenergy, and bioproducts. In: Sixth International Phytotechnologies Conference ; ...

320

Human Systems Center Products and Progress.  

Science.gov (United States)

... Page 43. Integrated Audio Technology Demonstrator The Integrated Audio Technology Dem- development for this application is successful. ...

1993-10-01

321

Feynman-Wiener path integral representation for scalar advected diffusion  

Energy Technology Data Exchange (ETDEWEB)

We write a path-integral expression for the Green function of a advected scalar on a fluid flux. (author)

2000-07-01

322

The possibility for formation of macro-cell corrosion in a liquid with low electrical conductivity  

International Nuclear Information System (INIS)

The possibility of electrochemical corrosion of carbon steel at the rate of 3.25 x 10"-"5 A/cm"2 in water was examined under the conditions present during an accidental pipe rupture at the Mihama nuclear power plant: liquid conductivity, 7.5 #mu#S/cm; dissolved oxygen concentration, 5 ppb or less; pH 8.6#propor to#9.3; ferrous ion concentration, 20 ppb or less; temperature, 142 C. The corrosion rate of iron in a micro-cell with a dissolved oxygen reduction cathode was estimated to be only 1/400 of the preceding rate. On the other hand, that in a micro-cell with a hydrogen ion reduction cathode was estimated to be as high as 1/10 of the preceding rate, that is, 3.25 x 10"-"6 A/cm"2. Two important factors may have influenced the corrosion rate: the remarkable wall thinning, which must have been the direct cause of the rupture of the pipe, was located close to, and downstream from, an orifice; and, the water temperature was in the range at which carbon steel makes a ...

2011-05-01

323

The Second International Piping Integrity Research Group (IPIRG-2) program. Final report, October 1991--April 1996  

Energy Technology Data Exchange (ETDEWEB)

The IPIRG-2 program was an international group program managed by the US NRC and funded by organizations from 15 nations. The emphasis of the IPIRG-2 program was the development of data to verify fracture analyses for cracked pipes and fittings subjected to dynamic/cyclic load histories typical of seismic events. The scope included: (1) the study of more complex dynamic/cyclic load histories, i.e., multi-frequency, variable amplitude, simulated seismic excitations, than those considered in the IPIRG-1 program, (2) crack sizes more typical of those considered in Leak-Before-Break (LBB) and in-service flaw evaluations, (3) through-wall-cracked pipe experiments which can be used to validate LBB-type fracture analyses, (4) cracks in and around pipe fittings, such as elbows, and (5) laboratory specimen and separate effect pipe experiments to provide better insight into the effects of dynamic and cyclic load histories. Also undertaken were an uncertainty analysis to ...

1997-03-01

324

Sodium arsanilate-induced vestibular dysfunction in meadow voles (Microtus pennsylvanicus): effects on posture, spontaneous locomotor activity and swimming behavior.  

Science.gov (United States)

Vestibular dysfunction was chemically induced in male meadow voles (Microtus pennsylvanicus) by intratympanic injections (30 mg per side) of sodium arsanilate (atoxyl). The control group received intratympanic injections of isotonic saline. After a one-week recovery period the voles were behaviorally assayed for integrity of their labyrinthine systems. All subjects were tested for the presence of the air-righting reflex and body rotation-induced nystagmus. Three weeks later a multivariate assessment of spontaneous motor activity of the voles was carried out in the automated Digiscan Activity Monitor. In addition, the swimming behavior of the voles was examined. Voles with vestibular dysfunction exhibited pronounced postural abnormalities (head dorsiflexion), were not able to swim with their nose above the water for a 1 min test period, and displayed disorientation and thrashing movements. In the Digiscan activity test the atoxyl-treated voles displayed ...

1992-03-15

325

Results of the remote sensing feasibility study for the uranium hexafluoride storage cylinder yard program  

Energy Technology Data Exchange (ETDEWEB)

The US DOE manages the safe storage of approximately 650,000 tons of depleted uranium hexafluoride remaining from the Cold War. This slightly radioactive, but chemically active, material is contained in more than 46,000 steel storage cylinders that are located at Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Some of the cylinders are more than 40 years old, and approximately 17,500 are considered problem cylinders because their physical integrity is questionable. These cylinders require an annual visual inspection. The remainder of the 46,000-plus cylinders must be visually inspected every four years. Currently, the cylinder inspection program is extremely labor intensive. Because these inspections are accomplished visually, they may not be effective in the early detection of leaking cylinders. The inspection program requires approximately 12--14 full-time-equivalent (FTE) employees. At the cost of approximately $125K per FTE, this translates to ...

1997-02-01

326

Oil shale, tar sand, coal research, advanced exploratory process technology jointly sponsored research. Quarterly technical progress report, April--June 1992  

Energy Technology Data Exchange (ETDEWEB)

Accomplishments for the quarter are presented for the following areas of research: oil shale, tar sand, coal, advanced exploratory process technology, and jointly sponsored research. Oil shale research includes; oil shale process studies, environmental base studies for oil shale, and miscellaneous basic concept studies. Tar sand research covers process development. Coal research includes; underground coal gasification, coal combustion, integrated coal processing concepts, and solid waste management. Advanced exploratory process technology includes; advanced process concepts, advanced mitigation concepts, and oil and gas technology. Jointly sponsored research includes: organic and inorganic hazardous waste stabilization; development and validation of a standard test method for sequential batch extraction fluid; operation and evaluation of the CO{sub 2} HUFF-N-PUFF Process; fly ash binder for unsurfaced road aggregates; solid state NMR analysis of Mesa Verde Group, ...

1992-12-01

327

A simulation of the transport and fate of radon-222 derived from thorium-230 low-level waste in the near-surface zone of the Radioactive Waste Management Site in Area 5 of the Nevada Test Site  

Energy Technology Data Exchange (ETDEWEB)

US Department of Energy (DOE) Order 5820.2A (DOE, 1988) requires performance assessments on all new and existing low-level radioactive waste (LLW) disposal sites. An integral part of performance assessment is estimating the fluxes of radioactive gases such as radon-220 and radon-222. Data needs pointed out by mathematical models drive site characterization. They provide a logical means of performing the required flux estimations. Thorium-230 waste, consisting largely of thorium hydroxide and thorium oxides, has been approved for disposal in shallow trenches and pits at the LLW Radioactive Waste Management Site in Area 5 of the Nevada Test Site. A sophisticated gas transport model, CASCADR8 (Lindstrom et al., 1992b), was used to simulate the transport and fate of radon-222 from its source of origin, nine feet below a closure cap of native soil, through the dry alluvial earth, to its point of release into the atmosphere. CASCADR8 is an M-chain gas-phase radionuclide ...

1993-12-01

328

Three-dimensional, three-component wall-PIV  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a new time-resolved three-dimensional, three-component (3D-3C) measurement technique called wall-PIV. It was developed to assess near wall flow fields and shear rates near non-planar surfaces. The method is based on light absorption according to Beer-Lambert's law. The fluid containing a molecular dye and seeded with buoyant particles is illuminated by a monochromatic, diffuse light. Due to the dye, the depth of view is limited to the near wall layer. The three-dimensional particle positions can be reconstructed by the intensities of the particle's projection on an image sensor. The flow estimation is performed by a new algorithm, based on learned particle trajectories. Possible sources of measurement errors related to the wall-PIV technique are analyzed. The accuracy analysis was based on single particle experiments and a three-dimensional artificial data set ...

2010-06-15

329

The influence of wall deposits on heat transfer in combustion engines. Einfluss von Wandablagerungen auf den Waermeuebergang im Verbrennungsmotor  

Energy Technology Data Exchange (ETDEWEB)

The experimental survey about the heat transfer between the working fluid and the combustion chamber wall with a direct injection diesel engine has shown the production of a soot layer with increasing loads on the combustion chamber wall. Because the combustion process of methanol occurs without the formation of wall deposits, the same engine spark ignitioned with methanol at the same conditions has shown a higher heat transfer coefficient. Because the heat losses do not only depend on the heat transfer coefficient but also on the driving temperature difference between the working fluid and the combustion chamber wall, the methanol engine with corresponding process management showed lower heat losses than the diesel engine at nearly the same load. (orig./HW)

1994-04-01

330

Effect of convective wall currents on the air quality of source ventilation. Einfluss konvektiver Wandstroemungen auf die Luftqualitaet bei Quellueftung  

Energy Technology Data Exchange (ETDEWEB)

With the combination of source ventilation and ceiling cooling for air-conditioning of working and recreation rooms, a ventilation system is available which fulfills the highest demands regarding thermal comfort. In order to utilize the advantages of this ventilation system with regard to air quality and thermal comfort to an optimum, the influence of the radiation exchange between cooling ceiling and walls on the flow in the room is investigated experimentally. Energy transfer from the walls to the cooled ceiling may result in an insufficient temperature of the walls compared to ambient air and in an upward flow on the wall surfaces (downward flow of) driven by gravity, which influences the flow pattern in the case of source ventilation. (orig.)

1993-07-01

331

Dispersoid separation method and apparatus  

Energy Technology Data Exchange (ETDEWEB)

Improved separation of heavier material from a dispersoid of gas and heavier material entrained therein is taught by the method of this invention which advantageously uses apparatus embodied in an inertial separator having rotary partition means comprising wall members dividing a housing into a plurality of axially-extending through passages arranged in parallel. Simultaneously with the helical transit of a moving stream of the dispersoid through the parallel arrangement of axially-extending through passages at a constant angular velocity, the heavier material is driven radially to the collecting surfaces of the rotational wall members where it is collected while the wall members are rotating at the same angular velocity as the moving stream. The plurality of wall members not only provides an increased area of collecting surfaces but the positioning of each of the wall members ...

1980-01-01

332

A comparative assessment of slope stability of New Orleans I-wall with partial gap between the wall and layered cohesive backfill  

British Library Electronic Table of Contents (United Kingdom)

Following Hurricane Katrina, the study of cantilevered sheet pile I-wall with gap or partial gap has become one of the central elements of the ongoing investigation pertaining to the re-building of hurricane protection systems in New Orleans, LA. Historically, the US Army Corps of Engineers (USACE) had mostly relied upon the Method of Planes (MOP) analysis procedure for slope stability analysis of I-wall systems. However MOP is a simplified procedure which does not satisfy total equilibrium. Nevertheless, MOP is still considered by USACE as a popular analysis tool because of its simplicity and ease of use in slope stability analysis. This paper demonstrates the applicability and suitability of MOP as a viable analysis tool for the analysis of New Orleans I-wall founded on layered cohesive ...

2011-01-01

333

Wind turbulence estimates in a valley by coherent Doppler lidar  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this paper, the effect of several turbulence parameters during various flow conditions in Owens Valley, educed from coherent Doppler lidar data have been studied. Radial velocity structure functions are processed to estimate the turbulent kinetic energy (TKE) dissipation rate, integral length scale and velocity variance, assuming a theoretical model for isotropic wind fields. Corrections for turbulence measurements have been considered to address the complications due to inherent volumetric averaging of radial velocity over each range gate, noise of the lidar data, and the assumptions required to estimate effects of smaller scales of motion on turbulence quantities. Using data from the Terrain-induced Rotor Experiment (T-REX) in April-May 2006, vertical profiles of wind and tur...

2011-01-01

334

Wear resistant composite structure of vitreous carbon containing convoluted fibers  

Energy Technology Data Exchange (ETDEWEB)

Very good friction and wear measurements are reported for MRCC (metal reinforced carbon composites), made from low-wear non-graphitic carbon matrix with metal-fiber reinforcement. Counterfaces include austenitic and martensitic stainless steels, Si nitride, and alumina. Effects of high load, high temperature, and gaseous environments are reported: removal of humidity, atm. oxygen have little effect on friction, wear for MRCC sliding against ceramic or stainless steel. Wear of Al oxide riders on MRCC is very low, not affected by contact load. 260 C temperatures do not degrade performance of 440-C riders on MRCC disks or raise friction. In small or large sizes, MRCC is made in a single-pass process for about the same volume cost as cast iron. It can survive heating in nitrogen above 1600 C without loss of integrity or major change of dimensions.

1995-02-01

335

User-Centered Design: Experience, Progress, Challenges; User-Centered Design: Erfahrungen, Erfolge und Herausforderungen  

Energy Technology Data Exchange (ETDEWEB)

This presentation gives an overview of IBM's experience with its approach to usability engineering, User-Centered Design (UCD), which has been introduced nearly one decade ago. It discusses the characteristics of User-Centered Design and the critical factors for successful deployment: - Establishing a culture for usability engineering. - Making User-Centered Design an integral part of the development process. - Multi-disciplinary teams for the design and evaluation of the total user experience. - Building up organizational structures and an infrastructure for methods, tools, communication, and education. - Applying UCD to UCD itself to continuously improve its process and methods. (orig.)

2002-07-01

336

The assessment of defects in thin shells subject to secondary stress  

International Nuclear Information System (INIS)

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

1981-08-21

337

Sensitivity analysis: Interaction of DOE SNF and packaging materials  

International Nuclear Information System (INIS)

A sensitivity analysis was conducted to evaluate the technical issues pertaining to possible destructive interactions between spent nuclear fuels (SNFs) and the stainless steel canisters. When issues are identified through such an analysis, they provide the technical basis for answering what if questions and, if needed, for conducting additional analyses, testing, or other efforts to resolve them in order to base the licensing on solid technical grounds. The analysis reported herein systematically assessed the chemical and physical properties and the potential interactions of the materials that comprise typical US Department of Energy (DOE) SNFs and the stainless steel canisters in which they will be stored, transported, and placed in a geologic repository for final disposition. The primary focus in each step of the analysis was to identify any possible phenomena that could potentially compromise the structural integrity of the canisters and to ...

1999-06-06

338

Remote sensing; Fernerkundung  

Energy Technology Data Exchange (ETDEWEB)

The potential of different multitemporal and multispectral airborne and spaceborne remote sensing methods for assessment and monitoring of the lignite open-cast mining areas are discussed in this chapter. Emphasis is placed on the successful use of different remote sensing data in variable vegetation structures for dumped sediments with different mineralogical and geochemical properties and for hydrochemical properties of the residual lakes. Multiple remote sensing data are a cost and time efficient tool for the assessment of environmental impacts, supervising of reclamation activities as well as for long term monitoring of the mining area. The airborne data are well suited for large scale detailed research and mapping in smaller sites and the satellite data for the overview scale 1:50 000. An integrated remote sensing-GIS-system including all field and lab data, DTM and other graphical data, improve the results of the remote sensing data ...

2001-07-01

339

Preparation of biodegradable PLA/PLGA membranes with PGA mesh and their application for periodontal guided tissue regeneration  

International Nuclear Information System (INIS)

A biodegradable polylactic acid (PLA)/poly(glycolide-co-lactide) copolymer (PLGA) membrane with polyglycolic acid (PGA) mesh was prepared to aid the effective regeneration of defective periodontal tissues. The microporous membrane used in this study consists of biodegradable polymers, and seems to have a structure to provide appropriate properties for periodontal tissue regeneration. Based on the albumin permeation test, it is known that the biodegradable membrane exhibits the suitable permeability of nutrients. The membrane maintained its physical integrity for 6-8 weeks, which could be sufficient to retain space in the periodontal pocket. Cell attachment and cytotoxicity tests were performed with respect to the evaluation of biocompatibility of the membrane. As a result, the membrane did not show any cytotoxicity. The safety and therapeutic efficacies of the biodegradable membranes were confirmed in animal tests.

2009-10-01

340

Plan for addressing issues relating to oil shale plant siting  

Energy Technology Data Exchange (ETDEWEB)

The Western Research Institute plan for addressing oil shale plant siting methodology calls for identifying the available resources such as oil shale, water, topography and transportation, and human resources. Restrictions on development are addressed: land ownership, land use, water rights, environment, socioeconomics, culture, health and safety, and other institutional restrictions. Descriptions of the technologies for development of oil shale resources are included. The impacts of oil shale development on the environment, socioeconomic structure, water availability, and other conditions are discussed. Finally, the Western Research Institute plan proposes to integrate these topics to develop a flow chart for oil shale plant siting. Western Research Institute has (1) identified relative topics for shale oil plant siting, (2) surveyed both published and unpublished information, and (3) identified data gaps and research needs. 910 refs., 3 ...

1987-09-01

341

PET and MRI in cardiac imaging: from validation studies to integrated applications  

International Nuclear Information System (INIS)

Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and allows accurate detection of coronary artery disease by assessment of myocardial perfusion. Magnetic resonance imaging (MRI) provides high resolution anatomical images that allow accurate evaluation of ventricular structure and function together with detection of myocardial infarction. Potential hybrid PET/MR tomography may potentially facilitate the combination of information from these imaging modalities in cardiology. Furthermore, the combination of anatomical MRI images with the high sensitivity of PET for detecting molecular targets may extent the application of these modalities to the characterization of atherosclerotic plaques and to the evaluation of angiogenetic or stem cell therapies, for example. This article reviews studies using MRI and PET in parallel to compare their performance in cardiac applications together with the potential benefits ...

2009-03-01

342

Multi-channel customer management: Delighting consumers, driving efficiency  

British Library Electronic Table of Contents (United Kingdom)

In today's maturing consumer markets, emphasis is shifting from straightforward sales to a more holistic approach to customer life cycle management, with a stronger emphasis on how sales are generated and service provided all along the customer journey. Effectively managing these different marketing, sales and service channels poses a significant challenge. Companies need new strategies, structures, processes and tools to deliver customer value across all channels. A multi-channel, integrative customer model that delivers customer value and significant return on investment (ROI) requires both a strong understanding of customer preferences and behaviours and a robust IT architecture that supports the overarching customer relationship management (CRM) strategy. Even those organizations that ...

2010-01-01

343

Morphological and histological study of larval development of the Senegal sole Solea senegalensis: an integrative study  

British Library Electronic Table of Contents (United Kingdom)

This study provides a comprehensive description of the main morphological and histological events that take place during larval and post-larval development of Senegal sole Solea senegalensis in order to establish a reference for its normal developmental organogenesis. Five stages have been described. Before gill development at the onset of metamorphosis (eye migration process, stage 4c), the skin was the main site of gas and ion exchange, whereas during stages 3 and 4, the skin begins differentiating into the definitive juvenile structure. The timing of development of the endocrine system depends on each organ, the endocrine pancreas and thyroid gland being the first to differentiate (stages 2 and 3, respectively), followed by the interrenal tissue and stannius corpuscles that develop at m...

2011-01-01

344

Moral Judgments Recruit Domain-General Valuation Mechanisms to Integrate Representations of Probability and Magnitude  

British Library Electronic Table of Contents (United Kingdom)

Summary Many important moral decisions, particularly at the policy level, require the evaluation of choices involving outcomes of variable magnitude and probability. Many economic decisions involve the same problem. It is not known whether and to what extent these structurally isomorphic decisions rely on common neural mechanisms. Subjects undergoing fMRI evaluated the moral acceptability of sacrificing a single life to save a larger group of variable size and probability of dying without action. Paralleling research on economic decision making, the ventromedial prefrontal cortex and ventral striatum were specifically sensitive to the "expected moral value" of actions, i.e., the expected number of lives lost/saved. Likewise, the right anterior insula was specifically sensitive to outcome p...

2010-01-01

345

Improved recovery demonstration for Williston basin carbonates. Quarterly technical progress report, October 1, 1995--December 31, 1995  

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional and multi-component seismic area is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1996-02-01

346

Improved recovery demonstration for Williston basin carbonates. Annual report, June 10, 1994--June 9, 1995  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.

1995-09-01

347

Improved recovery demonstration for Williston Basin carbonates. Quarterly technical progress report, October--December 1996  

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional (3D) and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short-lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1997-04-01

348

Improved recovery demonstration for Williston Basin carbonates. Annual report, June 10, 1995--June 9, 1996  

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.

1996-09-01

349

Improved recovery demonstration for Williston Basin carbonates  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in- place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional (3D) and multi- component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short- lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1996-09-01

350

Improved recovery demonstration for Williston Basin carbonates  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determination of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional (3D) is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in- place will result in additional oil production by primary and enhanced recovery processes.

1997-12-01

351

Improved Recovery Demonstration for Williston Basin Carbonates.  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in- place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional (3-D) and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short-lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimate of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1997-12-31

352

Improved Recovery Demonstration for Williston Basin Carbonates  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in- place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional (3-D) and multi- component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short- lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimate of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1997-03-01

353

Improved Recovery Demonstration for Williston Basin Carbonates  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with short-lateral and horizontal drilling technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

1997-12-31

354

Horticultural and Gathering Practices Complement Each Other: A Case Study in a Rural Population of Northwestern Patagonia  

British Library Electronic Table of Contents (United Kingdom)

We investigated gathering and cultivating practices and how they complement each other in a rural population of Northwestern Patagonia. We analyzed plant diversity, species similarity, biogeographic origin, and plant use by means of semi-structured interviews and field visits. Pichi Leufu inhabitants used 173 species: 138 cultivated plants, mainly for edible purposes, and 45 wild species principally for medicinal use. Most cultivated species were exotic (91.3%), whereas gathered plants were both native and exotic. While locals maintained vegetable gardens, the adoption of greenhouses improved conditions for certain crops. The integration of novel practices with ancestral knowledge suggests resilient processes in this community, probably reflected in the dynamics of current horticultural an...

2011-01-01

355

Development of In-Service Inspection system for heat transfer tubes in the primary pressurized water cooler in the HTTR  

International Nuclear Information System (INIS)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

1999-08-22

356

Development of In-Service Inspection system for heat transfer tubes in the primary pressurized water cooler in the HTTR  

Energy Technology Data Exchange (ETDEWEB)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

1999-08-01

357

Determination of radon and thoron permeability through some plastics by track technique  

Energy Technology Data Exchange (ETDEWEB)

Experiments have been performed to study the usefulness of several types of plastic foils as filter to separate radon and thoron. Time-integrated alpha-activity measurements have been carried out by using the so-called ''can-technique'' equipped with both LR-115 and CR-39 track detectors. The track density observed on the detectors, taken as a measure of radon activity concentration, has been determined as a function of the thickness of filter foils. The radon permeability and the thoron separation factors have been determined. It is shown that various plastic foils exhibit considerable differences in radon diffusion coefficient owing to their different chemical structures. Among the plastic foils investigated the polyethylene proved to have the highest gas diffusion coefficient.

1986-01-01

358

Cold source moderator vessel development for the High Flux Isotope Reactor: Thermal-hydraulic studies  

Energy Technology Data Exchange (ETDEWEB)

A project is underway at Oak Ridge National Laboratory (ORNL) to design, test, and install a cold neutron source facility in the High Flux Isotope Reactor (HFIR). This new cold source employs supercritical hydrogen at cryogenic temperatures both as the medium for neutron moderation and as the working fluid for removal of internally-generated nuclear heating. The competing design goals of minimizing moderator vessel mass and providing adequate structural integrity for the vessel motivated the requirement of detailed multidimensional thermal-hydraulic analyses of the moderator vessel as a critical design subtask. This paper provides a summary review of the HFIR cold source moderator vessel design and a description of the thermal-hydraulic studies that were carried out to support the vessel development.

1998-07-01

359

Algebraic structures and eigenstates for integrable collective field theories  

International Nuclear Information System (INIS)

Conditions for the construction of polynomial eigen-operators for the Hamiltonian of collective string field theories are explored. Such eigen-operators arise for only one monomial potential v(x)=#mu#x"2 in the collective field theory. They form a w_#infinity#-algebra isomorphic to the algebra of vertex operators in 2d gravity. Polynomial potentials of orders only strictly larger or smaller than 2 have no non-zero-energy polynomial eigen-operators. This analysis leads us to consider a particular potential #nu#(x)=#mu#x"2+g/x"2. A Lie algebra of polynomial eigen-operators is then constructed for this potential. It is a symmetric 2-index Lie algebra, also represented as a subalgebra of U(sl(2)). (orig.).

1992-02-01

360

ASFIT-VARI: A practical gamma-ray transport code for MS-DOS computers  

Energy Technology Data Exchange (ETDEWEB)

The ASFIT (Anisotropic Source-Flux Iteration Technique) code was first developed in India about 1970 to solve the radiation transport equation represented in the form of coupled integral equations separating the spatial and energy-angular transmissions. The ASFIT code uses a nodal structure in the wavelength [lambda] domain in Compton units (CU) rather than in the energy domain. The ASFIT-VARI code is the latest version available from the Radiation Shielding Information Center. It incorporates variable dimensioning and has been adapted for use on MS-DOS personal computers using the Ryan-McFarland or Microsoft Version 5.0 FORTRAN compilers. While earlier versions used point cross sections (well suited for gamma-ray transport), the present version also allows multigroup cross sections for neutron and coupled neutron-gamma-ray transport.

1990-01-01

361

A six-axes robot for deep water applications  

Energy Technology Data Exchange (ETDEWEB)

The six-axes industrial robot MANUTEC r15 UW was modified to work underwater and successfully tested down to the simulated water depth of 1100 m. Next step in the program was to use this robot as a handling tool for inspection tasks at the welding seam of an underwater structure conducted with CCD-cameras and distance sensors. This was also to demonstrate the possibility to assist and later on to replace divers from this work. Additional research was focussed on the stiffness and rigidity of the robot during the precise guiding of tools and workpieces under current water conditions up to a flow velocity of 1.1 m/s. Present work is concentrated on the application of this subsea robot on a maintenance task at the Brazilian underwater template OCTOS-1000. For this experiments the robot is integrated in a large mock-up which simulates a quarter section of this template. (orig.)

1994-01-01

362

A He-gas Cooled, Stationary Granular Target  

CERN Document Server

In the CERN approach to the design of a neutrino factory, the repetition frequency of the proton beam is high enough to consider stationary solid targets as a viable solution for multi-MW beams. The target consists of high density tantalum spheres of 2 mm diameter which can efficiently be cooled by passing a high mass flow He-gas stream through the voids between the Ta-granules. Very small thermal shocks and stresses will arise in this fine grained structure due to the relatively long burst of 3.3 ms from the SPL-proton linac. In a quadruple target system where each target receives only one quarter of the total beam power of 4 MW, conservative temperature levels and adequate lifetimes of the target are estimated in its very high radiation environment. A conceptual design of the integration of the target into the magnetic horn-pion-collector is presented.

2003-01-01

363

Innovative Structural and Joining Concepts for Lightweight Design of Heavy Vehicle Systems  

Energy Technology Data Exchange (ETDEWEB)

The extensive research and development effort was initiated by the U.S. Department of Energy (DOE) in 2002 at West Virginia University (WVU) in order to investigate practical ways of reducing the structural weight and increasing the durability of heavy vehicles through the judicious use of lightweight composite materials. While this project was initially focused on specific Metal Matrix Composite (MMC) material, namely Aluminum/Silicon Carbide (Al/SiC) commercially referenced as ''LANXIDE'', the current research effort was expanded from the component level to the system level and from MMC to other composite material systems. Broadening the scope of this research is warranted not only by the structural and economical deficiencies of the ''LANXIDE'' MMC material, but also by the strong coupling that exists between the material and the geometric characteristics of the ...

2006-09-30

364

Characterization of the surface film growth during the electrochemical process: Part 2 (90 % copper-10 % nickel system)  

Energy Technology Data Exchange (ETDEWEB)

In order to understand the resistance of passive films formed during corrosion processes, an analytical technique using x-ray diffraction was developed to examine the structure of metal in closest proximity to the metal/liquid interface. The in-situ structure at the metal liquid interface was examined for 90 % copper and 10 % nickel (90-10 Cu-Ni) in KOH solution at room temperature and at four different potentistatically controlled potentials ({minus}0.5 V, {minus}0.1 V, +0.5 V and +0.10 V versus Ni/NiO). The chemical changes at the metal interface were studied over a period of 48 hours. It was found that the integrity of the 90-10 Cu-Ni foil in KOH was lost after a continued application of the potential over 48 hours. The x-ray diffraction results indicated that the structure of both the inner and the outer passive layers, at {minus}0.5V and {minus}0.1 V (versus Ni/NiO), is comprised of Ni(OH){sub 2}, ...

1998-06-01

365

Unsteady state heat transfer in the vertical walls of a building  

Energy Technology Data Exchange (ETDEWEB)

The unsteady state heat transfer behaviour of a vertical wall subject to the effects of uniform radiation is investigated and the dimensional analysis of combined heat transfers by conduction, convection and radiation is presented. The convective heat transfer coefficients used in the numerical model are determined experimentally by means of an assembly resembling the conditions encountered in the dwelling (variable temperatures and heat flows in time and space, wall associated with a floor, radiative flux outside the wall). In routine conditions (homogeneous wall dimensions, temperature differentials less than 40/sup 0/C), it is shown that the problem depends in practice on three parameters (instead of five) and that nomographs can give the energy accumulated in the wall as a function of its geometric and thermal charactersitics and the external conditions (type and thickness of ...

1982-12-01

366

Novel silicon fabrication process for high-aspect-ratio micromachined parts  

Energy Technology Data Exchange (ETDEWEB)

Bulk micromachining generally refers to processes involving wet chemical etching of structures formed out of the silicon substrate and so is limited to fairly large, crude structures. Surface micromachining allows intricate patterning of thin films of polysilicon and other materials to form essentially two-dimensional layered parts (since the thickness of the parts is limited by the thickness of the deposited films). There is a third type of micromachining in which the part is formed by filling a mold which was defined by photolithographic means. Historically micromachining molds have been formed in some sort of photopolymer, be it with x-ray lithography (``LIGA``) or more conventional UV lithography, with the aim of producing piece parts. Recently, however, several groups including ours at Sandia have independently come up with the idea of forming the mold for mechanical parts by etching into the silicon substrate itself. In Sandia`s mold ...

1995-08-01

367

The ZNF804A gene: characterization of a novel neural risk mechanism for the major psychoses.  

Science.gov (United States)

Schizophrenia and bipolar disorder share genetic risk, brain vulnerability, and clinical symptoms. The ZNF804A risk variant, rs1344706, confers susceptibility for both disorders. This study aimed to identify neural mechanisms common to both schizophrenia and bipolar disorder through this variant's potential effects on cortical thickness, white matter tract integrity, and cognitive function. Imaging, genetics, and cognitive measures were ascertained in 62 healthy adults aged between 18 and 59 years. High-resolution multimodal MRI/DTI imaging was used to measure cortical thickness and major frontotemporal and interhemispheric white matter tracts. The general linear model was used to examine the influence of the ZNF804A rs1344706 risk variant on cortical thickness, white matter tract integrity, and cognitive measures. Individuals homozygous for the risk variant ('A' allele) demonstrated reduced cortical gray matter thickness in the superior ...

2011-04-27

368

Integrated design environment for human performance and human reliability analysis  

Energy Technology Data Exchange (ETDEWEB)

Work over the last few years at the Idaho National Engineering and Environmental Laboratory (INEEL) has included a major focus on applying human performance and human reliability knowledge and methods as an integral element of system design and development. This work has been pursued in programs in a wide variety of technical domains, beginning with nuclear power plant operations. Since the mid-1980`s the laboratory has transferred the methods and tools developed in the nuclear domain to military weapons systems and aircraft, offshore oil and shipping operations, and commercial aviation operations and aircraft design. Through these diverse applications the laboratory has developed an integrated approach and framework for application of human performance analysis, human reliability analysis (HRA), operational data analysis, and simulation studies of human performance to the design and development of complex systems. This approach was recently ...

1997-05-01

369

Development of Program Evaluating the Effects on the Secondary Side of Steam Generator due to Foreign Objects  

Energy Technology Data Exchange (ETDEWEB)

When materials such as metal are into the secondary side of steam generator, they, so called foreign objects, may have influences on the integrity of the steam generator tubes. They cause the tube wear due to the relative motion between the tubes and foreign objects and the tube impact due to flow. The best way to avoid the effects is to remove all the foreign objects. However, it is not easy to remove the foreign materials thoroughly due to their condition such as the location. If the locations of the foreign materials are in the middle of tube bundle and the tube arrangement of the steam generator is the triangle type, the equipment such as FOSAR(Foreign Object Search and Retrieval) can not reach their locations. If the foreign materials stick together with the tubes or tube sheet, they can not be removed. In the case of operating the steam generator with the foreign materials, the licensee must prove that the materials do not affect the tube ...

2005-07-01

370

Development of Program Evaluating the Effects on the Secondary Side of Steam Generator due to Foreign Objects  

International Nuclear Information System (INIS)

When materials such as metal are into the secondary side of steam generator, they, so called foreign objects, may have influences on the integrity of the steam generator tubes. They cause the tube wear due to the relative motion between the tubes and foreign objects and the tube impact due to flow. The best way to avoid the effects is to remove all the foreign objects. However, it is not easy to remove the foreign materials thoroughly due to their condition such as the location. If the locations of the foreign materials are in the middle of tube bundle and the tube arrangement of the steam generator is the triangle type, the equipment such as FOSAR(Foreign Object Search and Retrieval) can not reach their locations. If the foreign materials stick together with the tubes or tube sheet, they can not be removed. In the case of operating the steam generator with the foreign materials, the licensee must prove that the materials do not affect the tube ...

2005-10-27

371

Analysis of impurities in beryllium, affecting evaluation of the tritium breeding ratio  

International Nuclear Information System (INIS)

In most conceptual fusion power reactor designs, it is proposed to use beryllium as a neutron multiplier in the blanket. Detailed chemical composition of beryllium is necessary for evaluation of the tritium breeding ratio, and estimating the activation and transmutation of beryllium in the fusion reactor. In the present report, special attention was paid to a detailed analysis of impurities in beryllium, relevant to the tritium breeding ratio evaluation. Two different methods were used for the study of impurities: an analysis of the local sample by the ICP-MS method, and an integral analysis of the beryllium assembly, using the pulsed neutron method. The latter method was proposed as the most effective way of analyzing the integral effect to impurities in beryllium on production of the tritium on the lithium-6. The evaluation of the integral effect was based on time behaviour observations of the thermal neutron flux, ...

372

The effects of spatially distributed ionisation sources on the temperature structure of HII region  

CERN Document Server

Spatially resolved studies of star forming regions show that the assumption of spherical geometry is not realistic in most cases, with a major complication posed by the gas being ionised by multiple non-centrally located stars or star clusters. We try to isolate the effects of multiple non-centrally located stars on the temperature and ionisation structure of HII regions, via the construction of 3D photoionisation models using the 3D Monte Carlo photoionisation code MOCASSIN. We find that the true temperature fluctuations due to the stellar distribution (as opposed to the large-scale temperature gradients due to other gas properties) are small in all cases and not a significant cause of error in metallicity studies. Strong emission lines from HII regions are often used to study the metallicity of star-forming regions. We compare integrated emission line spectra from our models and quantify any systematic errors caused by the simplifying ...

2007-01-01

373

The (N,M)-th KdV hierarchy and the associated W algebra  

International Nuclear Information System (INIS)

We discuss a differential integrable hierarchy, which we call the (N, M)-th KdV hierarchy, whose Lax operator is obtained by properly adding M pseudo-differential terms to the Lax operator of the N-th KdV hierarchy. This new hierarchy contains both the higher KdV hierarchy and multi-field representation of KP hierarchy as sub-systems and naturally appears in multi-matrix models. The (N+2M-1) coordinates or fields of this hierarchy satisfy two algebras of compatible Poisson brackets which are local and polynomial. Each Poisson structure generate an extended W_1_+_#infinity# and W_#infinity# algebra, respectively. We call W (N, M) the generating algebra of the extended W_#infinity# algebra. This algebra, which corresponds with the second Poisson structure, shares many features of the usual W_N algebra. We show that there exist M distinct reductions of the (N, M)-th KdV hierarchy, which are obtained by imposing suitable second ...

1993-01-01

374

Structure activity relationships to assess new chemicals under TSCA  

International Nuclear Information System (INIS)

Under Section 5 of the Toxic Substances Control Act (TSCA), manufacturers must notify the US Environmental Protection Agency (EPA) 90 days before manufacturing, processing, or importing a new chemical substance. This is referred to as a premanufacture notice (PMN). The PMN must contain certain information including chemical identity, production volume, proposed uses, estimates of exposure and release, and any health or environmental test data that are available to the submitter. Because there is no explicit statutory authority that requires testing of new chemicals prior to their entry into the market, most PMNs are submitted with little or no data. As a result, EPA has developed special techniques for hazard assessment of PMN chemicals. These include (1) evaluation of available data on the chemical itself, (2) evaluation of data on analogues of the PMN, or evaluation of data on metabolites or analogues of metabolites of the PMN, (3) use of quantitative structure ...

1990-06-27

375

RCRA closure of the Building 3001 Storage Canal  

Energy Technology Data Exchange (ETDEWEB)

The 3001 Storage Canal is located under portions of Buildings 3001 and 3019 at Oak Ridge National Laboratory (ORNL) and has a capacity of approximately 62,000 gallons of water. The term canal has historically been used to identify this structure, however, the canal is an in-ground reinforced concrete structure satisfying the regulatory definition of a tank. From 1943 through 1963, the canal in Building 3001 was designed to be an integral part of the system for handling irradiated fuel from the Oak Ridge Graphite Reactor. Because one of the main initial purposes of the reactor was to produce plutonium for the chemical processing pilot plant in Building 3019, the canal was designed to be the connecting link between the reactor and the pilot plant. During the war years, natural uranium slugs were irradiated in the reactor and then pushed out of the graphite matrix into the system of diversion plates and chutes which directed ...

1992-09-01

376

Fractal properties of spatial distributions of aftershocks and active faults  

Energy Technology Data Exchange (ETDEWEB)

The relationship between the fractal dimensions of spatial distributions of aftershocks and pre-existing active faults is examined. Fourteen mainshocks taking place in Japan were followed by aftershocks, and the aftershocks occur in swarms around the mainshocks. The epicentral distributions of the aftershocks exhibit fractal properties, and the fractal dimensions are estimated by using the two-point correlation integral. The pre-existing active fault systems observed in the 14 aftershock regions have fractal structures, and the fractal dimensions are estimated by using the box-counting method. A positive correlation between the estimated fractal dimensions is found, and it is independent on the mainshock magnitude. The correlation shows that aftershock distributions become less clustered with increasing the fractal dimensions of active fault systems. Namely, the fractal clusters of aftershocks are put under the constraint of the fractal ...

2004-01-01

377

Failure modes, reliability and integrity of floating storage unit (FPSO, FSU) turret and swivel systems  

Energy Technology Data Exchange (ETDEWEB)

This report provides an assessment of the designs of turret and swivel systems for floating production, storage and offloading (FPSO) vessels and floating storage Units (FSU) which are either purpose built or converted from tankers. Use of FPSO and FSO in the North Sea with the move to subsea and deepwater production is discussed, and the background to FPSO and FSU turret systems is traced. Details are given of general issues relating to ship structure, systems affecting the turret, swivel systems, mooring systems, turret loading, scaffolding and support structure, on-board personnel, and construction standards. Turret system components and types are described, and failure modes, operation and safety relevant components are examined. Inspection and maintenance, examples of good and poor practice, and applicable regulations are considered. Annexes list UK installations and present information on individual turret design, fluid transfer systems, ...

2002-07-01

378

Development of risk benefit structural design method for innovative nuclear plants II, fatigue crack growth model  

International Nuclear Information System (INIS)

In order to develop competitive and reliable nuclear power generation systems, development of innovative structural design methods is indispensable and risk-based design approach based on the assessment of failure probability is being developed. Fatigue is commonly considered as an important contributor to failure probability in many components of reactor systems and its assessment gives a large influence on total reliability of the plants. In order to assess its effect on the reliability, propagation of cracks needs to be evaluated as well as their initiation and pre-existence probability. As a part of new design approach, efforts are being taken to develop a simplified estimation method for fatigue crack growth under cyclic application of thermal and thermo-mechanical loading. A simplified estimation method of J-integral based on reference stress method and elastic follow-up factor was developed based on many finite element analyses and ...

2005-05-01

379

Construction and Calibration of the Laser Alignment System for the CMS Tracker  

CERN Document Server

The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 m and a length of 5.4 m representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure, providing stability within the working conditions of a 4 T solenoid magnetic field at ?10oC. Knowledge of the position of the silicon detectors at the level of 100 ?m is needed for an efficient pattern recognition of charged particle tracks. Metrology methods are used to survey tracker subdetectors and the integrated Laser Alignment System (LAS) provides absolute ...

2006-01-01

380

Algorithmic aspects and supercomputing trends in computational electromagnetics  

Energy Technology Data Exchange (ETDEWEB)

Accurate and rapid evaluation of radar signature for alternative aircraft/store configurations would be of substantial benefit in the evolution of integrated designs that meet RCS requirements across the threat spectrum. Finite-volume time domain methods offer the possibility of modeling the whole aircraft, including penetrable regions and stores, at longer wavelengths on today's supercomputers and at typical airborne radar wavelengths on the teraflop computers of tomorrow. A structure-grid finite-volume time domain CFD based RCS code has already been developed at the Rockwell Science Center, and this code incorporates modeling techniques for general radar absorbing materials and structures. Using this work as a base, the goal of the CFD based CEM effort is to define, implement, and evaluate various code development issues suitable for rapid prototype signature prediction addressing many issues related to physics ...

1993-01-01

381

A structured approach to the assessment of the quality culture in nuclear installation  

International Nuclear Information System (INIS)

INSAG has emphasized that safety culture has two general components: the organizational framework and the attitude of the staff. To develop a structured approach to the assessment of safety culture, we propose that the highly formalized nature of nuclear power plant organizations be exploited. The prime coordinating mechanism of NPP organizations is the standardization of work processes, where a work process is defined as a standardized sequence of tasks designed to achieve a specific goal (an example is the maintenance work process). The predictable nature of work processes is exploited by the Work Process Analysis Model (WPAM) to conduct a systematic analysis that identifies the desirable characteristics of work processes and develops performance measures for their strengths and weaknesses. These can provide a set of tangible characteristics of a good safety culture. It is argued in this paper that the analysis of normal power production and investment protection ...

1995-04-01

382

A novel CMOS charge-pump circuit with current mode control 110 mA at 2.7 V for telecommunication systems  

International Nuclear Information System (INIS)

This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSMC ...

2010-04-01

383

The phenomenon of microscale flow and mass transfer in medicinal herb materials  

Energy Technology Data Exchange (ETDEWEB)

Microwave assisted extraction (MAE) is a combination of a microwave technique and conventional solvent extraction used in the modernization of traditional Chinese medicine. The effective component of medicinal herbs is mostly cellular material which can be released via solvent extraction. The material is diffused to solvents via the porous membrane wall. The structure of herb morphology and characteristics of the solute's molecular weight play an important role in the extraction process of target compounds. Astragalus pieces were chosen for this study in which an ultra-filtration membrane method was used to determine the molecular weight distribution characteristics of Astragalus water extraction liquid in the process of MAE. The fine structure of matrix materials was also characterized by scanning election microscopy (SEM). The phenomenon of mass flow and mass transfer in the plant porous media was discussed along ...

2008-07-01

384

Research and development on plasma facing components for fusion reactors in JAEA  

International Nuclear Information System (INIS)

This paper presents the present status of R and D activities on plasma facing components for fusion reactors, such as International Thermonuclear Experimental Reactor (ITER) and fusion demonstration reactor (DEMO). The plasma facing components (PFCs) as typified by divertor and first wall components are subjected to high heat flux and particle flux from fusion plasma. It is essential for these components to have sufficient heat removal capability and robust structure against those loadings. JAEA has been carried out to develop the ITER-PFCs which consist of copper alloys and armor materials with high thermal conductivity, such as carbon fiber composites, tungsten and beryllium. The demonstration of the thermomechanical performance of the ITER-PFCs by using mock-ups has successfully been made under close mutual cooperation between the participant countries of ITER. Currently, the activity on the development of the ITER-PFCs is in a qualification ...

2008-10-13

385

Physical Modelling of Axisymmetric Turbulent Impinging Jets as used within the Nuclear Industry for Mobilisation of Sludges  

Energy Technology Data Exchange (ETDEWEB)

The impingement of a fluid jet onto a surface has broad applications across many industries. Within the UK nuclear industry, during the final stages of fuel reprocessing, impinging fluid jets are utilised to mobilise settled sludge material within storage tanks and ponds in preparation for transfer and ultimate immobilisation through vitrification. Despite the extensive applications of impinging jets within the nuclear and other industries, the study of two-phase, solid loaded, impinging jets is limited, and generally restricted to computational modelling. Surprisingly, very little fundamental understanding of the turbulence structure within such fluid flows through experimental investigation is found within the literature. The physical modelling of impinging jet systems could successfully serve to aid computer model validation, determine operating requirements, evaluate plant throughput requirements, optimise process operations and support design. Within this ...

2008-07-01

386

Options for passive containment cooling in next-generation nuclear plant designs  

International Nuclear Information System (INIS)

A design for passive cooling of large containment structures has progressed sufficiently to move forward into the detailed design stage necessary for plant construction. For such application, a safety analysis report has already been submitted to the US Nuclear Regulatory Commission. The design considers an annulus between the inner steel containment vessel and outer, thick-walled concrete shield building with chimney-like natural convection cooling driven only by a density gradient relative to the atmosphere. Air within the annulus is heated as internal containment temperature rises and heat is transferred through the steel containment shell. The resulting air density gradient between the annulus and the environment causes the heated air to rise, producing a natural convection flow through inlets in the shield building, past the steel shell, and out an exit chimney. Several options for enhancing passive heat removal of large containment ...

1993-11-01

387

A cryocondensation pump for the DIII-D Advanced Divertor Program  

Energy Technology Data Exchange (ETDEWEB)

A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the water-cooled vacuum vessel wall. Supports for the pump were designed to ...

1992-03-01

388

Formation of metal oxides by cathodic arc deposition  

Energy Technology Data Exchange (ETDEWEB)

Cathodic arc deposition is an established and industrially applied technique for the formation of nitrides (e.g. TiN); it can also be used for metal oxide thin film formation. A cathodic arc plasma source with the desired cathode material is operated in an oxygen atmosphere of appropriate pressure, and metal oxides of various stoichiometric composition can be formed on different substrates. We report here on a series of experiments on metal oxide formation by cathodic arc deposition for different applications. Black copper oxide has been deposited on accelerator components to increase the radiative heat transfer between the parts. Various metal oxides such as tungsten oxide, niobium oxide, nickel oxide and vanadium oxide have been deposited on ITO glass to form electrochromic films for window applications. Optical waveguide structures can be formed by refractive index variation using oxide multilayers. We have synthesized multilayers of Al{sub 2}O{sub 3}-Y{sub ...

1995-11-01

389

A recursive reduction of tensor Feynman integrals  

Energy Technology Data Exchange (ETDEWEB)

We perform a recursive reduction of one-loop n-point rank R tensor Feynman integrals [in short: (n,R)-integrals] for n{<=}6 with R{<=}n by representing (n,R)-integrals in terms of (n,R-1)- and (n-1,R-1)-integrals. We use the known representation of tensor integrals in terms of scalar integrals in higher dimension, which are then reduced by recurrence relations to integrals in generic dimension. With a systematic application of metric tensor representations in terms of chords, and by decomposing and recombining these representations, we find the recursive reduction for the tensors. The procedure represents a compact, sequential algorithm for numerical evaluations of tensor Feynman integrals appearing in next-to-leading order contributions to massless and massive three- and four-particle production at LHC and ...

2009-08-15

390

Structural evolution of Lake Superior II: Eastern basin  

Energy Technology Data Exchange (ETDEWEB)

The authors have interpreted 1,400 km of industry and government multichannel seismic reflection data from eastern Lake Superior. Seismic sequences have been identified by using reflection character and reflector terminations and truncations. This framework, coupled with outcrop information, has allowed them to assign lithologic units to some of these reflectors and reconstruct the timing and geometry of structures within the basin. The authors have mapped the Base Jacobsville-Bayfield Group/Top oronto Group, Base oronto Group/Top Keweenawan volcanics, and Basement as well as several reflectors internal to these groups. Integration of gravity and magnetic data with the seismic grid permits regional mapping of faults and folds between seismic lines. In the eastern part of the basin, high-angle basement-involved reverse faults, such as the southeastern combination of the Keweenaw fault, trend NNW-SSE, while broad folds trend E-W. The Keweenaw ...

1992-01-01

391

On foundation of the generalized Nambu mechanics  

International Nuclear Information System (INIS)

We outline basic principles of a canonical formalism for the Nambu mechanics - a generalization of Hamiltonian mechanics proposed by Yoichiro Nambu in 1973. It is based on the notion of a Nambu bracket, which generalizes the Poisson bracket - a 'binary'' operation on classical observables on the phase space - to the 'multiple' operation of higher order n#>=#3. Nambu dynamics is described by the phase flow given by Nambu-Hamilton equations of motion - a system of ODE's which involves n-1 'Hamiltonians'. We introduce the fundamental identity for the Nambu bracket - a generalization of the Jacobi identity - as a consistency condition for the dynamics. We show that Nambu bracket structure defines a hierarchy of infinite families of 'subordinated' structures of lower order, including Poisson bracket structure, which satisfy certain matching conditions. The notion of Nambu bracket enables us to define Nambu-Poisson manifolds - ...

392

Architectural design criteria for f-block metal ion sequestering agents. 1998 annual progress report  

Energy Technology Data Exchange (ETDEWEB)

'The objective of this project is to provide a means to optimize ligand architecture for f-block metal recognition. The authors strategy builds on an innovative and successful molecular modeling approach in developing polyether ligand design criteria for the alkali and alkaline earth cations. The hypothesis underlying this proposal is that differences in metal ion binding with multidentate ligands bearing the same number and type of donor groups are primarily attributable to intramolecular steric factors. They propose quantifying these steric factors through the application of molecular mechanics models. The research involves close integration of theoretical and experimental chemistry. The experimental work entails synthesizing novel ligands and experimentally determining structures and binding constants for metal ion complexation by series of ligands in which architecture is systematically varied. The theoretical work entails using ...

1998-12-31

393

The integrated PWR; Les REP integres  

Energy Technology Data Exchange (ETDEWEB)

This document presents the integrated reactors concepts by a presentation of four reactors: PIUS, SIR, IRIS and CAREM. The core conception, the operating, the safety, the economical aspects and the possible users are detailed. From the performance of the classical integrated PWR, the necessity of new innovative fuels utilization, the research of a simplified design to make easier the safety and the KWh cost decrease, a new integrated reactor is presented: SCAR 600. (A.L.B.)

2002-07-01

394

Features of two hepatitis B virus (HBV) DNA integrations suggest mechanisms of HBV integration.  

UK PubMed Central (United Kingdom)

Two integrated hepatitis B virus (HBV) DNA molecules were cloned from two primary hepatocellular carcinomas each containing only a single integration. One integration (C3) contained a single linear...Full Text Available

1989-06-01

395

Enterprise integration: A tool`s perspective  

Energy Technology Data Exchange (ETDEWEB)

The advent of sophisticated automation equipment and computer hardware and software is changing the way manufacturing is carried out. To compete in the global marketplace, manufacturing companies must integrate these new technologies into their factories. In addition, they must integrate the planning, control, and data management methodologies needed to make effective use of these technologies. This paper provides an overview of recent approaches to achieving this enterprise integration. It then describes, using simulation as a particular example, a new tool`s perspective of enterprise integration.

1993-06-01

396

Turbulent heat transfer augmentation using microscale disturbances inside the viscous sublayer  

Energy Technology Data Exchange (ETDEWEB)

The authors report here on an experimental study of heat transfer augmentation in turbulent flow. Enhancement strategies employed in this investigation are based on the near-wall mixing processes induced in the sublayer through appropriate wall and near-wall streamwise-periodic disturbances. Experiments are performed in a low-turbulence wind-tunnel with a high-aspect-ratio rectangular channel having either (a) two-dimensional periodic microgrooves on the wall, or (b) two-dimensional microcylinders placed in the immediate vicinity of the wall. It is found that microdisturbances placed inside the sublayer induce favorable heat-transport augmentation with respect to the smooth-wall case, in the near-analogous momentum and heat transfer behavior are preserved; a roughly commensurate increase in heat and momentum transport is termed favorable in that it leads to a ...

1992-05-01

397

Simultaneous assessment of left ventricular function from gated myocardial perfusion SPECT. Utility of QGS (Quantitative Gated SPECT) program  

International Nuclear Information System (INIS)

Quantitative gated SPECT (QGS) was evaluated in 7 normal volunteers and 31 patients with cardiac diseases. Adequate cut off value of a prefilter was 0.45. In phantom, the left ventricular volume value was 93.9% of determined value by 180-degree projection in L type and 98.8% by 360-degree projection in opposed type. In normal volunteers, LVEF measured by QGS program related to value by first pass method. As for functional map, regional EF and wall motion decreased at the septum side, and wall thickening at base side of heart. Good correlation was recognized (p<0.0001) between blood flow image and functional map (regional EF and wall thickening). In 20 cases of acute myocardial infarction, lesion was detected conspicuously in regional EF and wall motion. The accuracy of coronary arterial stenosis improved in functional map (regional EF 92%, wall motion 92% and ...

1998-08-01

398

The EU HT test programme of ITER primary wall small scale mock ups  

International Nuclear Information System (INIS)

This paper summarises the main results obtained so far in the frame of the EU Home Team test programme of ITER primary wall small scale mock ups. It describes briefly the fabrication method of the mock ups, the test conditions and the main results obtained with high heat flux and thermal fatigue tests of Cu alloy/stainless steel and beryllium/Cu alloy/stainless steel mock ups. The results obtained so far show good thermal fatigue performance and operation margin of the ITER primary first wall concept. (author)

1998-09-07

399

Main achievements of the EU HT test programme of ITER primary wall small scale mock ups  

International Nuclear Information System (INIS)

This paper presents the main achievements of the European Home Team (EU HT) test programme of ITER primary wall small scale mock ups. It describes briefly the fabrication method of the mock ups, the test conditions and the main results obtained with high heat flux and thermal fatigue tests of Cu alloy/stainless steel and beryllium/Cu alloy/stainless steel mock ups. The results obtained so far show very good thermal fatigue performance and operation margin of the ITER primary first wall concept.

2000-11-01

400

Creation of an antiferromagnetic exchange spring  

Science.gov (United States)

We present evidence for the creation of an exchange spring in an antiferromagnet due to exchange coupling to a ferromagnet. X-ray magnetic linear dichroism spectroscopy on single crystal Co/NiO(001) shows that a partial domain wall is wound up at the surface of the antiferromagnet when the adjacent ferromagnet is rotated by a magnetic field. We determine the interface exchange stiffness and the antiferromagnetic domain wall energy from the field dependence of the direction of the antiferromagnetic axis, the antiferromagnetic pendant to a ferromagnetic hysteresis loop. The existence of a planar antiferromagnetic domain wall, proven by our measurement, is a key assumption of most exchange bias models.

2004-04-06

401

Conjugate parallel-flowing free and forced convection boundary layers on vertical wall sides  

Energy Technology Data Exchange (ETDEWEB)

The paper describes an analytical study of two parallel-flowing boundary layers of free and forced convection modes on the facing sides of a vertical thin wall. The two layers are analyzed separately within the framework of boundary layer theory, and coupled by the matching conditions at wall. Numerical data are obtained for a wide range of a dimensionless conjugation parameter {zeta} relating the heat transfer effectiveness of two convection modes. Based on these data, an expression for calculating the conjugate mean Nusselt number as a function of {zeta}-parameter is found by means of a curve-fitting method. (orig.)

2003-02-01

402

Aspiration cover for the loading site of a belt conveyer  

Energy Technology Data Exchange (ETDEWEB)

An aspiration cover is proposed for the site of loading a belt conveyer including a housing arranged above the belt conveyer in whose cover there is an aspiration sleeve and a discharge chute from the upper wall and a guide having a cushioning plate on the lower end. It is distinguished by the fact that in order to improve the effectiveness of removing dust by decreasing the volume of aspirated air, the cover between the aspiration sleeve and the upper wall of the loading chute is convex in the inside of the housing and has a smooth connection to the upper wall of the discharge chute turned towards the cushioning plate.

1982-01-01

403

WALL PRESSURE FLUCTUATIONS UNDER TURBULENT ...  

Science.gov (United States)

... necessary to allow for the effata nr the finits size of the oressure tranaducer on both the root mean square and power spectral density measurements ...

1963-04-01

404

Strain Rate Effects on Ultimate Strain of Copper  

Science.gov (United States)

... Figure 3a. PETN Filled Tube Specimen Detonated by Exploding Bridgewire Specimen POLYETIILLENE END-CAP "1- 901am WALL IHICKNESS ...

1979-05-01

405

Semi Annual Progress Report on BLADE END WALL FLOWS IN COMPRESSORS ...  

Science.gov (United States)

Eckert, B., "Axial Kompressoren und Radial Kompressoren," Springer. Verlag, Berlin, 1953. 3. Lebot, Y., et al., "Theoretical and Experimental Determination ...

406

Review of Polyarylacetylene Matrices for Thin-Walled ...  

Science.gov (United States)

... After strip- ping off the chloroform, the dibromo ethyl (EDBEB) compounds are separated from the m-BDBEB using a thin film evaporator. ...

1989-09-25

407

Optimization of Hydrogen Consumption in Hydrogen Masers  

Science.gov (United States)

... Hydro- gen gas is fed through a temperature- controlled Pd-Ag leak 161 into a cylindrical double-walled Pyrex bulb, 15 cm long and 1.9 cm in ...

1990-08-06

408

Neural Tissues from the Implanted Stem Cells  

International Science & Technology Center (ISTC)

Morphological, Electrophysiological and Behavioral Investigations of the Nervous Tissue Developed from the Embryonic Matrix Zone Cells of the Dorsolateral Walls of Lateral Ventricles, Implanted into the Lesioned Regions of the Adult Rat's Brain

409

Mechanical jacks meant to support the movable shielding wall (Proton Room side) of the SC  

CERN Document Server

This mechanical version was soon after changed into a hydraulic jack one (the reason being a number of serious constructional defects).

1955-01-01

410

Glassy Carbon, Alloys  

Science.gov (United States)

... 2.2.1 Polymerization of DVB Under Pressure DVB was polymerized at 300*C in thin-walled Pd-Ag capsules at pressures up to 60,000 psi. ...

1972-07-27

411

Fractional domain walls from on-site softening in dipolar bosons  

CERN Document Server

We study dipolar bosons in a 1D optical lattice and identify a region in parameter space---strong coupling but relatively weak on-site repulsion---hosting a series of stable CDW states whose low-energy excitations, built from "fractional domain walls", are remarkably similar to those of non-abelian fractional quantum Hall states. Here, a conventional domain wall between translated CDW's may split by inserting strings of degenerate, but inequivalent, CDW states. Outside these insulating regions, we find numerous supersolids as well as a superfluid regime. The mentioned phases should be accessible experimentally, and in particular, the fractional domain walls can be created in the ground state using single-site addressing, i.e. by locally changing the chemical potential.

2011-01-01

412

FINAL REPORT CONTINUOUS SCANNING METEOROLOGICAL CAMERA SYSTEM FOR ...  

Science.gov (United States)

was deemed adequate and a cooling system designed utilizing the Melcor CP2-15- 10B thermoelectric module. Wall temperature achieved with this system was - 36 ...

413

DESIGN OF A CONVECTIVE COOLING SYSTEM FOR A MACH 6 - NASA ...  

Science.gov (United States)

Figure 23 presented detailed layout of the cooling system designed for the Mach 6 hypersonic- transport. The distribution system consisted of thin-wall ...

414

Approximate solutions to the Stefan problem with internal heat generation  

Energy Technology Data Exchange (ETDEWEB)

Using a quasi-static approach valid for Stefan numbers less than one, we derive approximate equations governing the movement of a phase change front for materials which generate internal heat. These models are applied for both constant surface temperature and constant surface heat flux boundary conditions, in cylindrical, spherical, plane wall and semi-infinite geometries. Exact solutions with the constant surface temperature condition are obtained for the steady-state solidification thickness using the cylinder, sphere, and plane wall geometries which show that the thickness depends on the inverse square root of the internal heat generation. Under constant surface heat flux conditions, closed form equations can be obtained for the three geometries. In the case of the semi-infinite wall, we show that for constant temperature and constant heat flux out of the wall conditions, the solidification layer ...

2008-05-15

415

Analysis of Rough Wall Turbulent Heating with Application to ...  

Science.gov (United States)

... roughness. Since T u'v' and q v'"F the heat transfer augmentation is the square root of the skin friction augmentation: - 1/2 (( St - ,Cf 0 ...

1979-01-01

416

9902631 - Lysozyme - NASA  

Science.gov (United States)

Protein isolated from hen egg-white and functions as a bacteriostatic enzyme by degrading bacterial cell walls. First enzyme ever characterized by protein ...

417

Is the Kaiser Permanente model superior in terms of clinical integration?: a comparative study of Kaiser Permanente, Northern California and the Danish healthcare system  

UK PubMed Central (United Kingdom)

BackgroundIntegration of medical care across clinicians and settings could enhance the quality of care for patients. To date, there is limited data on the levels of integration in...Full Text Available

418

Complementarity of Integral and Differential Experiments for Reactor Physics Purposes.  

Science.gov (United States)

In this paper, the following topics are studied: uranium 238 effective integral; thermal range uranium 238 capture cross section; Americium 242 m capture cross section. The mentioned examples show that differential and integral experiments are both useful...

1981-01-01

419

Chromosomal sites for hepatitis B virus integration in human hepatocellular carcinoma.  

UK PubMed Central (United Kingdom)

The discovery that hepatitis B virus (HBV) integrates into host chromosomes raises the question of whether such viral DNA integration correlates directly with the activation of specific oncogenes or...Full Text Available

1991-12-01

420

THERMODYNAMICS AND KINETICS OF AQUEOUS PIPERAZINE WITH POTASSIUM CARBONATE FOR CARBON DIOXIDE ABSORPTION  

Energy Technology Data Exchange (ETDEWEB)

This work proposes an innovative blend of potassium carbonate (K{sub 2}CO{sub 3}) and piperazine (PZ) as a solvent for CO{sub 2} removal from combustion flue gas in an absorber/stripper. The equilibrium partial pressure and the rate of absorption of CO{sub 2} were measured in a wetted-wall column in 0.0 to 6.2 m K{sup +} and 0.6 to 3.6 m PZ at 25 to 110 C. The equilibrium speciation of the solution was determined by {sup 1}H NMR under similar conditions. A rigorous thermodynamic model, based on electrolyte non-random two-liquid (ENRTL) theory, was developed to represent equilibrium behavior. A rate model was developed to describe the absorption rate by integration of eddy diffusivity theory with complex kinetics. Both models were used to explain behavior in terms of equilibrium constants, activity coefficients, and rate constants. The addition of potassium to the amine increases the concentration of CO{sub 3}{sup 2-}/HCO{sub 3}{sup -} in ...

2005-04-18

421

LOBI/B-R1M, Loop for Blowdown Investigation, PWR Single-Ended Cold-Leg Break Experiment B EXP.B  

International Nuclear Information System (INIS)

1 - Description of test facility: The LOBI facility is a 1/700 scale model of a four loop PWR and has two primary loops, the intact loop representing three loops and the broken loop representing one loop of a four-loop PWR. The reactor pressure vessel model contains an electrically heated rod-bundle with 64 rods and a heated length of 3.9 m. The nominal heating power is 5.3 MW. The downcomer is of annular shape. An upper head simulator is connected to the vessel. Each of the two primary loops contains a pump and a steam generator. The different mass flows in the loops are established by the pump speeds, since the two pumps are identical. Heat is removed from the steam generators by a secondary system. ECC water can be supplied from two accumulators, one for each loop. Cold or hot leg as well as combined injection can be simulated. The LOBI test facility is the only high pressure integral test facility within the European Communities (1982), built and operated in ...

422

Development of Guide System for a Reactor Head Maintenance Robot  

Energy Technology Data Exchange (ETDEWEB)

The Control Rod Drive(CRD) nozzles for PWR nuclear power plants(NPP) house the control rod drives. The number of nozzle penetrations range from the mid-30's to over 100 in each reactor head. The integrity of CRD nozzles is very important, because the primary pressure boundary is established with the J-groove weld joining the nozzle to the head clad surface. The Alloy 600 PWSC CRD nozzle leaks discovered in the fall of 2000 and spring of 2001 in several US plants. Therefore the NRC has recommended a more proactive effort by US utilities to inspect similarly susceptible nozzles in all US plants. The primary safety concern is circumferential cracks that can permit the nozzles to separate from the head at high velocity and produce a large-break leak in the reactor vessel. A secondary concern is head leakage from any through-wall cracks in the nozzle or J-groove weld area. Numerous inspection and repair tools have been developed to address ...

2005-07-01

423

Heat transfer augmentation of a circular pipe flow using nano-particle layers  

International Nuclear Information System (INIS)

For the advanced fusion reactor FFHR2 (Force Free Helical Reactor) that has been proposed by NIFS, molten salt Flibe (LiF:BeF2=64:36) breeder blanket system is selected because of Flibe's features such as chemical stability, low-pressure operation and low electric conductivity. The Flibe is however high Prandtl number fluid since it has high viscosity and low thermal conductivity. Therefore its heat transfer performance is low compared with liquid Li or Pb-Li. In addition to heat removal of 1MW/m2 on the first wall, electrolysis of molten salt due to MHD effect will take place under high flow rate condition. This indicates that heat transfer enhancement under low flow rate is essential for the Flibe blanket system. In our laboratory, heat transfer characteristics of molten salt HTS (KNO3:NaNO2:NaNO3=53:40:7), have been evaluated, which is used as a simulant fluid of Flibe from the points of view of Be's toxicity and similar Prandtl number. In this paper, we adopt ...

2007-10-05

424

Sleeping Beauty Transposition From Nonintegrating Lentivirus  

UK PubMed Central (United Kingdom)

Lentiviral vectors enter cells with high efficiency and deliver stable transduction through integration into host chromosomes, but their preference for integration within actively transcribing genes...Full Text Available

2009-07-01

426

Integration of Microdialysis Sampling and Microchip Electrophoresis with Electrochemical Detection  

UK PubMed Central (United Kingdom)

Here we describe the fabrication, optimization, and application of a microfluidic device that integrates microdialysis (MD) sampling, microchip electrophoresis (ME), and electrochemical detection...Full Text Available

2008-12-01

427

Integration of Armored Forces in the US Army Infantry Division  

Science.gov (United States)

... Infantry Division A Monograph by ... 5b. GRANT NUMBER 4. TITLE AND SUBTITLE Integration of Armored Forces in the US Army Infantry Division ...

2001-01-01

428

Feynman path integral representations for wave scattering by anisotropic perturbations  

Energy Technology Data Exchange (ETDEWEB)

We write a space-time Feynman Path Integral representation for scattered wave fields from a weakly/compact supported anisotropic non-homogeneity. (author)

2007-07-01

429

Effects and side-effects of integrating care: the case of mental health care in the Netherlands  

UK PubMed Central (United Kingdom)

PurposeDescription and analysis of the effects and side-effects of integrated mental health care in the Netherlands.Context of caseDue...Full Text Available

430

A highly integrated trigger and readout system for a silicon micro-strip detector installed at the CERN Omega spectrometer  

CERN Document Server

A highly integrated trigger and readout system for a silicon micro-strip detector installed at the CERN Omega spectrometer

1991-01-01

431

Tissue structure, nuclear organization and gene expression in normal and malignant breast  

Energy Technology Data Exchange (ETDEWEB)

Because every cell within the body has the same genetic information, a significant problem in biology is to understand how cells within a tissue express genes selectively. A sophisticated network of physical and biochemical signals converge in a highly orchestrated manner to bring about the exquisite regulation that governs gene expression in diverse tissues. Thus, the ultimate decision of a cell to proliferate, express tissue-specific genes, or apoptose must be a coordinated response to its adhesive, growth factor, and hormonal milieu. The unifying hypothesis examined in this overview is that the unit of function in higher organisms is neither the genome nor the cell alone but the complex, three-dimensional tissue. This is because there are bidirectional connections between the components of the cellular microenvironment (growth factors, hormones, and extracellular matrix) and the nucl2048 These connections are made via membrane-bound receptors and transmitted to the nucleus, where ...

2000-01-27

432

Local chromatin structure of heterochromatin regulates repeatedDNA stability, nucleolus structure, and genome integrity  

Energy Technology Data Exchange (ETDEWEB)

Heterochromatin constitutes a significant portion of the genome in higher eukaryotes; approximately 30% in Drosophila and human. Heterochromatin contains a high repeat DNA content and a low density of protein-encoding genes. In contrast, euchromatin is composed mostly of unique sequences and contains the majority of single-copy genes. Genetic and cytological studies demonstrated that heterochromatin exhibits regulatory roles in chromosome organization, centromere function and telomere protection. As an epigenetically regulated structure, heterochromatin formation is not defined by any DNA sequence consensus. Heterochromatin is characterized by its association with nucleosomes containing methylated-lysine 9 of histone H3 (H3K9me), heterochromatin protein 1 (HP1) that binds H3K9me, and Su(var)3-9, which methylates H3K9 and binds HP1. Heterochromatin formation and functions are influenced by HP1, Su(var)3-9, and the RNA interference (RNAi) pathway. My thesis project ...

2007-05-05

433

Modeling of turbulent bubbly flows; Modelisation des ecoulements turbulents a bulles  

Energy Technology Data Exchange (ETDEWEB)

The two-phase flows involve interfacial interactions which modify significantly the structure of the mean and fluctuating flow fields. The design of the two-fluid models adapted to industrial flows requires the taking into account of the effect of these interactions in the closure relations adopted. The work developed in this thesis concerns the development of first order two-fluid models deduced by reduction of second order closures. The adopted reasoning, based on the principle of decomposition of the Reynolds stress tensor into two statistically independent contributions turbulent and pseudo-turbulent parts, allows to preserve the physical contents of the second order relations closure. Analysis of the turbulence structure in two basic flows: homogeneous bubbly flows uniform and with a constant shear allows to deduce a formulation of the two-phase turbulent viscosity involving the characteristic scales of bubbly turbulence, as well as an ...

2005-03-15

434

Mass spectrometric characterization of elements and molecules in cell cultures and tissues  

Energy Technology Data Exchange (ETDEWEB)

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and laser post-ionization secondary neutral mass spectrometry (laser-SNMS) have been used to image and quantify targeted compounds, intrinsic elements and molecules with subcellular resolution in single cells of both cell cultures and tissues. Special preparation procedures for analyzing cell cultures and tissue materials were developed. Cancer cells type MeWo, incubated with boronated compounds, were sandwiched between two substrates, cryofixed, freeze-fractured and freeze-dried. Also, after injection with boronated compounds, different types of mouse tissues were extracted, prepared on a special specimen carrier and plunged with high velocity into LN{sub 2}-cooled propane for cryofixation. After trimming, these tissue blocks were freeze-dried. The measurements of the K/Na ratio demonstrated that for both cell cultures and tissue materials the special preparation techniques used were appropriate for preserving the chemical and ...

2006-07-30

435

Ionizing radiation target groups of band 3 inserted into egg lecithin liposomes as determined by Raman spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C-H stretching region bands recorded at temperatures from 25 to -22[sup o]C. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm[sup -1] (amide I), 1200-1300 cm[sup -1] (amide III) and 550-1030 cm[sup -1] (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm[sup -1] are tyrosines and cysteines. The radiation-induced changes in the secondary structure were ...

1993-03-01

436

Ionizing radiation target groups of band 3 inserted into egg lecithin liposomes as determined by Raman spectroscopy  

International Nuclear Information System (INIS)

The purified integral membrane protein, band 3, from human erythrocytes was inserted into egg lecithin liposomes. The insertion of band 3 was determined from thermal transition data from the analysis of the C-H stretching region bands recorded at temperatures from 25 to -22"oC. Raman spectra show that band 3 considerably broadens and lowers the thermal transition of egg lecithin liposomes, suggesting the insertion of band 3. The band 3-inserted liposomes were irradiated with gamma-rays (40 Gy) and the radiation target groups were determined by the analysis of the structural sensitive Raman bands in the 1600-1700 cm"-"1 (amide I), 1200-1300 cm"-"1 (amide III) and 550-1030 cm"-"1 (side chain amino groups) regions. The radiation-sensitive groups as identified from Raman spectra in the region 550-1030 cm"-"1 are tyrosines and cysteines. The radiation-induced changes in the secondary structure were determined from amide I and ...

437

Influence of anchor behaviour on the earthquake response of liquid storage tanks  

International Nuclear Information System (INIS)

The dynamic response of thin liquid storage tanks to earthquakes is a very complicated phenomenon, because it can be highly non linear. Among others, one can meet material and geometric non linearities of the tank shell leading eventually to static or dynamic buckling non linear behavior of anchor bolts, contact non-linearities due to the uplift of the tank base and to the unilateral character of the fluid pressure on the shell and high amplitude fluid oscillations. Moreover, linear or non linear soil structure interaction affects considerably the response of the fluid structure system under consideration. In this paper we focus attention on problems related only to the base uplift and anchors plastification. We study a tank similar to the Hualien project tank, but we neglect the soil structure interaction. The studied tank is representative of medium height to radius ratio ratio tanks with relatively thick bottom plate. ...

438

Importance of neutron data in fission reactor applications  

International Nuclear Information System (INIS)

The neutron data required to completely analyze fission reactors includes many isotopes and covers a broad energy range. In both fast and thermal reactors, the neutron inventory is a fine balance determined by the fission properties of "2"3"5U, "2"3"9Pu and "2"3"8U and by the capture cross sections of "2"3"8U, fuel materials, structural materials and coolant materials. In fast reactors, the spectrum of neutrons ranges from 1 keV to 3 MeV and is influenced by the elastic and inelastic scattering properties of "2"3"8U and the structural and coolant materials. For neutron shielding applications, the important neutron data include the total cross sections of structural and coolant materials in the MeV range. The impact of these basic nuclear data in fission reactor applications is most suitably described by sensitivity analysis. For example, sensitivity coefficients computed for a typical large plutonium fueled fast reactor ...

1976-07-06

439

Electronic and structural properties of #beta#-Be_3N_2  

International Nuclear Information System (INIS)

We report the results of a theoretical study of the electronic and structural properties of the hexagonal beryllium nitride, using first principle pseudopotential plane wave (PP-PW) as well as full potential linearized augmented plane wave (FP-LAPW) methods within density functional theory. In the case of PP-PW we generated the pseudopotential by the highly optimized Q_c-tuning method and used the local density approximation and generalized gradient approximation (GGA) for the exchange-correlation potential. We applied pressure on the unit cell by the Wentzcovitch and traditional methods. In the FP-LAPW approach only the GGA was used for the exchange-correlation potential. Our calculated values for structural properties, based on both approaches are in reasonable agreement with experimental and other theoretical (Hartree Fock) results. By applying the above two approaches and also the Tight Binding Linear Muffin Thin Orbital method, the ground ...

440

Eddy current signal analysis techniques for assessing degradation of support plate structures in nuclear steam generators  

Energy Technology Data Exchange (ETDEWEB)

The steam generator (SG) is one of the most critical components of the heat transfer system in nuclear generation stations. Testing the structural integrity of SG tubing and SG internals is a key element of the fitness-for-service assessments to assure the safe and continuous operation of nuclear power plants. Recent eddy current (ET) inspections of two nuclear power plants revealed degradation of some of the tube support plate (TSP) structures, which was also confirmed by visual inspection. The phenomena was described as metal loss, caused by flow-accelerated corrosion of the carbon steel trefoil support plate and varying from minor to complete loss of the ligaments. This loss of TSP ligaments results in lack of support for the adjacent tubes making them more susceptible to fretting-wear damage and fatigue cracking. A signal analysis method, based on the responses at low frequency of two types of eddy current probes, has ...

2006-07-01

441

Void fraction and phase distribution of a rotating two-phase gas-liquid flow around a plasma arc under water  

Energy Technology Data Exchange (ETDEWEB)

Plasma arc welding processes are used in off-shore industry for construction and maintenance in the wet surrounding of underwater structures and pipelines. In greater water depth the density of the plasma gas increase because of the greater hydrostatic pressure. This causes the increase of conductive heat losses to the wet surrounding. To keep up the energy flux to the workpiece to be welded, the plasma arc has to burn in a local dry area with an inside pressure of 1 bar. This requirement can be fulfilled by a rotating cylinder with a liquid film flowing down the inner wall. The flow around the rotating cylinder to create a local dry area around the plasma arc under water is experimentally investigated. The rotating cylinder is placed above the work surface which is simulated by a flat plate. According to the centrifugal forces of the rotating flow inside the gap between the lower end of the cylinder and the flat plate the water is forced out ...

1994-12-31

442

Thermal performance of phase change wallboard for residential cooling application  

Energy Technology Data Exchange (ETDEWEB)

Cooling of residential California buildings contributes significantly to electrical consumption and peak power demand mainly due to very poor load factors in milder climates. Thermal mass can be utilized to reduce the peak-power demand, downsize the cooling systems, and/or switch to low-energy cooling sources. Large thermal storage devices have been used in the past to overcome the shortcomings of alternative cooling sources, or to avoid high demand charges. The manufacturing of phase change material (PCM) implemented in gypsum board, plaster or other wall-covering material, would permit the thermal storage to become part of the building structure. PCMs have two important advantages as storage media: they can offer an order-of-magnitude increase in thermal storage capacity, and their discharge is almost isothermal. This allows the storage of high amounts of energy without significantly changing the temperature of the room envelope. As heat ...

1997-04-01

443

Silicon nitride films deposited from SiH sub 2 Cl sub 2 -NH sub 3 by low pressure chemical vapor deposition: kinetics, thermodynamics, composition and structure  

Energy Technology Data Exchange (ETDEWEB)

The growth of stoichiometric and non-stoichiometric silicon nitride films was studied experimentally on 100 mm silicon wafers by batch depositions from the dichlorosilane (SiH{sub 2}Cl{sub 2})-ammonia (NH{sub 3}) system in a hot-wall horizontal low pressure chemical vapor deposition (LPCVD) reactor. The growth kinetics were discussed in terms of the Langmuir adsorption isotherm. The kinetic parameters were determined by comparing the experimental data with a one-dimensional simulation model. The decomposition of NH{sub 3} at high temperatures was included in the simulation procedure. When the SiH{sub 2}Cl{sub 2}:NH{sub 3} ratios were greater than 1.5, a quantity higher than the thermodynamic critical values above which Si-rich nitride films begin to deposit, various SiN{sub x} films with x < 4/3 were obtained. The composition of the SiN{sub x} films was found to vary along the LPCVD reactor. The film stoichiometry was examined by Rutherford backscattering and ...

1992-06-15

444

Short-term inhibition of ADP-induced platelet aggregation by clopidogrel ameliorates radiation-induced toxicity in rat small intestine.  

Science.gov (United States)

Endothelial dysfunction and increased platelet aggregation may be involved in the pathogenesis of normal tissue radiation toxicity. This study assessed clopidogrel, an inhibitor of ADP-induced platelet aggregation, as a modulator of intestinal radiation injury (radiation enteropathy). Rat small intestine was exposed to 21 Gy X-radiation. Clopidogrel (20 mg/kg/day) or vehicle was administered from 2 days before to 10 days after irradiation. Structural radiation injury, neutrophil infiltration, smooth muscle cell proliferation, collagen content, and TGF-beta1 expression were assessed 2 weeks (early phase) and 26 weeks (delayed phase) after irradiation, using quantitative histology and immunohistochemistry, morphometry, and real-time fluorogenic probe RT-PCR. Irradiated intestine exhibited significant histopathologic injury, reduced mucosal surface area, vascular sclerosis, intestinal wall fibrosis, increased collagen content, and increased ...

2002-01-01

445

Properties of SiC/SiC joining s and coatings for fusion  

International Nuclear Information System (INIS)

Full text of publication follows: As SiCf/SiC composites are very low activation materials, their use as structural material for the reactor blanket and first wall components appears essential to demonstrate the potential of D-T fusion power reactor. Positive features of SiCf/SiC are their high performances at elevated operating temperature and the ability to produce a specific component. Critical issues of SiCf/SiC are the mechanical properties, radiation stability and, with regard to technological issues, their hermeticity and joining processes. Improvement of joining processes for SiC/SiC components is also needed. Recently, several blanket designs have been studied: the TAURO blanket concept in the European Union, the ARIESAT concept in the US and the DREAM concept in Japan. In those reactors, hermetic SiCf/SiC or self-sealing coatings are mandatory. The basic idea of self sealing concept is to manufacture a coating with specific ...

2007-12-10

446

Dismembered Archean ophiolite in the SE. Wind River Mountains, Wyoming  

Energy Technology Data Exchange (ETDEWEB)

Ophiolitic rocks occur as wall rocks of the 2.7 Ga Louis Lake batholith near Atlantic City, Wyoming. All of the Archean rocks are strongly deformed and metamorphosed to a greenschist and amphibolite facies, but relict structures and textures are commonly preserved. These include the following, from west to east: (1) metadiabase with rare coarse-grained metagabbro; (2) ultramafic rocks and metagabbro; (3) amphibolite, locally pillowed, overlain(.) by pelitic schist, banded iron formation, and quartzite; and (4) pillow lavas, massive sills or flows, and minor metasedimentary rocks. Slice 1 locally contains parallel dike margins and rare metagabbro screens; these features suggest that it may represent a sheeted dike complex. Slice 2 locally contains ultramafic rocks having relict cumulus textures and igneous layering, corresponding to the cumulus portion of an ophiolite. The pillow lavas of slice 4 and possibly slice 3 are interpreted as ...

1985-01-01

447

Determination of the distribution of incident solar radiation in cavity receivers with approximately real parabolic dish collectors  

Energy Technology Data Exchange (ETDEWEB)

The absorption of solar heat and the attendant thermal and mechanical loadings on the tubes of cavity receivers depend predominantly on the flux distribution of the incident solar radiation. For an axially symmetric cavity receiver with a parabolic dish collector, it is simple to determine the insolation pattern on the receiver internal surfaces if the system is ideal. In such a system the surface of the dish is perfectly parabolic (no contour flaws are present), and the sun's central ray impinges on the dish surface parallel to the focal axis (no sun tracking flaws are present). These two conditions cannot be achieved in practice, and therefore the feasible parabolic dish system is referred to as a real system although, in actual fact, it is only an approximation to any actual system. The purpose of this paper is to devise calculation principles which permit analysis of a receiver designed for ideal conditions to verify its structural adequacy under the ...

1990-11-01

448

A comparison study on activation safety of fusion, fission and hybrid reactor technology  

Energy Technology Data Exchange (ETDEWEB)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment Reactor/Next European ...

1994-12-31

449

A comparison study on activation safety of fusion, fission and hybrid reactor technology  

International Nuclear Information System (INIS)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment Reactor/Next European ...

450

TRANSMUTATIONS IN SiC IRRADIATED IN ARIES-IV FIRST WALL  

Science.gov (United States)

The change in concentrations of elements due to transmutations resulting from neutron irradiation in the first wall of the ARIES-IV conceptual fusion energy device were determined as a function of neutron dose. SiC burns out at a rate of about 0.5% per effective full power year. The largest impurity concentration is that of He, but several other elements burn in at rates of hundreds of appm/efpy.

2001-04-01

451

Steelbiz Shop  

Wastenet

... The composite ground floor is suitable for support to all types of wall construction and can be used equally well on strip footings or mini-pile foundations . The light steel edge beams provide the accurate template required for internal timber or light steel wall frames to minimise fitting time and eliminate rework. The floated slab surface will accept floor finishes directly and thermal insulation can be easily fitted beneath ...

452

Solar collectors with tubes partially filled with porous substrates  

Energy Technology Data Exchange (ETDEWEB)

In this work, the thermal performance of a conventional collector is improved by inserting porous substrates at the inner walls of the collector tubes. The porous substrates improve the convective heat transfer coefficient between the tube wall and the fluid. This improvement is investigated numerically and its effects on the efficiency and the useful gain of the collector are evaluated. It is found that inserting the porous substrate may raise the collector efficiency considerably, especially at high values of the overall heat loss coefficient.

1999-02-01

453

Polymeric wall sealant test for radon control in a uranium mine  

International Nuclear Information System (INIS)

The effectiveness of an acrylic latex wall sealant in limiting the escape of radon from rock in underground mines is the subject of this paper. Application of the latex as a two-coat system over a fillter coat of gunite produced a reduction of radon concentration from an initial level of 80 to 100 pCi/L to a final average of 25 to 30 pCi/L under similar conditions.

454

NAME=\\  

Wastenet

...direct-injection systems Atomisation from hole-type nozzles (gasoline and diesel) under cavitating flow conditions Spray-wall interaction in gasoline direct injection engines Spray-wall interaction in direct-injection diesel engines Evaporation of multi-component fuels Cavitation in diesel injectors Nozzle flow, air motion, spray development and combustion in marine diesel engines ...

455

Free convection heat and mass transfer to steady flow in a semi-infinite vertical porous medium  

Science.gov (United States)

Analytical solutions are derived for a flow in a semi-infinite vertical porous medium with heat and mass transfer. When the temperature and mass concentration are uniform a constant pressure is possible and sustains a fully developed flow. Thereafter there is a small perturbation on the wall temperature and concentration and the subsequent two-dimensional problem is tackled for a large Prandtl number, free convection parameters and small Reynolds number. The heat transfer rate at the wall is discussed quantitatively.

1988-02-01

456

Fouling Study of Silicon Oxide Pores Exposed to Tap Water  

Energy Technology Data Exchange (ETDEWEB)

We report on the fouling of Focused Ion Beam (FIB)-fabricated silicon oxide nanopores after exposure to tap water for two weeks. Pore clogging was monitored by Scanning Electron Microscopy (SEM) on both bare silicon oxide and chemically functionalized nanopores. While fouling occurred on hydrophilic silicon oxide pore walls, the hydrophobic nature of alkane chains prevented clogging on the chemically functionalized pore walls. These results have implications for nanopore sensing platform design.

2007-07-12

457

Fabrication of nanoscale Ti honeycombs by focused ion beam  

Energy Technology Data Exchange (ETDEWEB)

Ti honeycombs with the side of 800 and 400 nm were fabricated by focused ion beam (FIB), though the surfaces of the bottom and wall of the Ti honeycombs were rough, as compared with the surfaces of the bottom and wall of the Si honeycomb. It is demonstrated that the nanoscale Ti components can be fabricated in a short time by FIB.

2003-03-15

458

Doublet III limiter/armor update  

Energy Technology Data Exchange (ETDEWEB)

The Doublet III device is operating with an extensive system of plasma limiters and wall protective armor. Operations with up to 8MW of neutral beam power and 1.5MA plasma current are planned. Design and operational performance of the following systems are discussed: 1. Water-cooled graphite moveable limiter. 2. Water-cooled graphite fixed limiter and neutral beam wall armor. 3. Radiatively cooled Inconel divertor plates.

1983-12-01

459

Battery side terminal  

Energy Technology Data Exchange (ETDEWEB)

A side terminal battery is described comprising: a casing having a side wall made from a moldable material; and a plug formed of relatively deformable, electrically conductive, corrosion resistant material molded into the side wall to form a seal between the interior and exterior of the casing and including a battery terminal insert embedded therein so as to be exposed at the exterior of the casing and isolated, by the plug, from the interior of the casing.

1988-03-08

460

Symmetries in nuclei near the centre of the f{sub 7/2} shell  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in the mirror pair nuclei {sup 49}Cr and {sup 49}Mn and their cross-conjugate partners, the mirror pair {sup 47}V and {sup 47}Cr have been investigated using experimental {gamma}-ray spectroscopic techniques. The combination of high-efficiency EUROBALL cluster Germanium detectors and clean exit-channel gating afforded by a 31-element silicon ball used in conjunction with a 15-detector neutron wall allowed a revision and extension to the energy level schemes of all four nuclei up to J{sup {pi}}=31{sup -}/2. The difference in excitation energy between states of equivalent spin in the parent nucleus and its analogue partner have thus been established for both mirror pairs up to the f{sub 7/2}-shell band terminating state for the first time. This difference is assumed to be due almost entirely to the Coulomb effect and is therefore called the Coulomb energy difference (CED). The variation in the CED with spin has been interpreted as reflecting the ...

1998-10-01

461

[caCORE: core architecture of bioinformation on cancer research in America].  

Science.gov (United States)

A critical factor in the advancement of biomedical research is the ease with which data can be integrated, redistributed and analyzed both within and across domains. This paper summarizes the Biomedical Information Core Infrastructure built by National Cancer Institute Center for Bioinformatics in America (NCICB). The main product from the Core Infrastructure is caCORE--cancer Common Ontologic Reference Environment, which is the infrastructure backbone supporting data management and application development at NCICB. The paper explains the structure and function of caCORE: (1) Enterprise Vocabulary Services (EVS). They provide controlled vocabulary, dictionary and thesaurus services, and EVS produces the NCI Thesaurus and the NCI Metathesaurus; (2) The Cancer Data Standards Repository (caDSR). It provides a metadata registry for common data elements. (3) Cancer Bioinformatics Infrastructure Objects (caBIO). They provide Java, Simple Object ...

2006-04-18

462

Weld integrity of the superconducting cable aluminium jackets of W7-X  

Energy Technology Data Exchange (ETDEWEB)

The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fuer Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The weld is mechanically loaded during cool-down due to the difference in thermal contractions between the GRP insulation and the aluminium, and during operation ...

2009-06-15

463

Weld integrity of the superconducting cable aluminium jackets of W7-X  

International Nuclear Information System (INIS)

The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fuer Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The weld is mechanically loaded during cool-down due to the difference in thermal contractions between the GRP insulation and the aluminium, and during operation ...

2009-06-01

464

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

465

Improved recovery demonstration for Williston Basin carbonates. Final report  

Science.gov (United States)

The purpose of this project was to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, and methods for improved completion efficiency. The investigations and demonstrations were focussed on Red River and Ratcliffe reservoirs in the Williston Basin within portions of Montana, North Dakota and South Dakota. Both of these formations have been successfully explored with conventional 2-dimensional (2D) seismic. Improved reservoir characterization utilizing 3-dimensional (3D) seismic was investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterizations were integrated with geological and engineering studies. The project tested lateral completion techniques, including high-pressure jetting lance technology and short-radius lateral drilling to enhance completion efficiency. Lateral completions should improve economics for both primary and ...

1998-07-01

466

High-resolution sequence stratigraphy from outcrop study, with the integration of log and seismic data  

Energy Technology Data Exchange (ETDEWEB)

The detailed sequence stratigraphic analysis of the siliciclastic-dominated Late Cretaceous sediments (Aren Sandstone and Garumnian red beds, south central Pyrenees, Spain) reveals the repeating disposition of critical elements and controlling mechanisms of cycles and sequences. Our approach integrates (a) hierarchy of unconformity-bounded units, (b) physical expression of boundaries traceable from the continent to the basin, (c) featuring facies and depositional systems, (d) well log and seismic expression, and (e) driving basing-filling mechanisms. A comparison to other active basins is suggested in order to prove the validity beyond the regional scale. Four basin-wide transgressive facies cycles were identified and interpreted as third-order units. The transgressive phase of each cycle is represented by mixed shelf deposits, while regressive periods consists of complex delta systems. The cycles are composed within their regressive phase of fourth-order ...

1993-09-01

467

Computational Fluid Dynamic Analysis of Core Bypass Flow Phenomena in a Prismatic VHTR  

Energy Technology Data Exchange (ETDEWEB)

The core bypass flow in a prismatic very high temperature gas-cooled reactor (VHTR) is one of the important design considerations which impacts considerably on the integrity of reactor core internals including operating fuels. The interstitial gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The occurrence of hot spots in the core and lower plenum and hot streaking in the lower plenum (regions of very hot gas flow) will be affected by the bypass flow. In the present study, three-dimensional computational fluid dynamic (CFD) calculations of a typical prismatic VHTR are conducted to understand better the bypass flow phenomenon and establish the evaluation method in the reactor core using commercial CFD code FLUENT. Parametric ...

2010-09-01

468

BS in Ceramic and Materials Engineering at Clemson  

Science.gov (United States)

Description of courses, curriculum and degree program. "Ceramic and materials engineers design, develop, and participate in the manufacture of both standard and new materials intended for use in a wide variety of industries with diverse applications. These range from the semi-conductor to the aerospace and finally to the traditional ceramics industry. The broad scope of industrial responsibilities handled by ceramic and materials engineers requires knowledge in mathematics, science, engineering, and the social sciences, skills in problem solving, engineering analysis, design, and written and oral communication. The baccalaureate program integrates laboratory with classroom experiences to prepare students for life-long learning. Courses covering thermodynamics, kinetics, mechanical behavior, processing and characterization of materials prepare students for careers in industry and/or for graduate school. Clemson University baccalaureate graduates in Ceramic and ...

2007-01-01

469

Application of constraint-sensitive fracture mechanics to the assessment of girth weld integrity  

Energy Technology Data Exchange (ETDEWEB)

The dominant fracture parameters used in fracture mechanics analyses of pipelines are related to the asymptotic crack-tip stress and strain fields at the crack tip. This paper reviewed new developments in constraint-sensitive fracture mechanics for the assessment of pipeline girth weld integrity. Constraint theories and experimental studies were evaluated. Constraint models included brittle fracture models and ductile fracture models. Constraint models for brittle fracture are based on weakest link statistics and Weibull distribution. Specifically designed experimental tests are often necessary to derive the damage parameters of ductile fracture models. Experimental test data must then be calibrated with finite element analyses (FEA) to ensure that the correct damage parameters are chosen. The effects of specimen geometry and loading condition are characterized by the T stress, while Q stress is the hydrostatic stress defined by the difference between stress ...

2004-07-01

470

Powder collection apparatus/method  

Energy Technology Data Exchange (ETDEWEB)

Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally equal to the angle ...

1994-01-11

471

Four loss-of-flow accidents in the SEAFP first wall/blanket cooling system  

Energy Technology Data Exchange (ETDEWEB)

This report presents the thermal-hydraulic analysis of four Loss-of-Flow Accidents (LOFAs) in the first wall/blanket cooling system of the alternative SEAFP reactor design. The LOFAs considered result from a loss of electrical power for the recirculation pump in the primary cooling circuit. The analyses have been performed using the thermal-hydraulic system analysis code RELAP5/MOD3. In the analyses, special attention has been paid to the transient thermal-hydraulic behaviour of the cooling system and the temperature development in the first wall and blanket. For the LOFA without plasma shutdown, significant loss of heat removal due to dryout occurs at the midplane of the outboard first wall cooling pipes about 41 s after pump trip. For the three LOFA cases with emergency plasma shutdown that have been studied, the temperature increase in the Be-coating at the midplane of the outboard first wall is ...

1994-07-01

472

Enhanced CT in the diagnosis of acute appendicitis to evaluate the severity of disease. Comparison of CT findings and histological diagnosis  

Energy Technology Data Exchange (ETDEWEB)

To assess the potential of CT in evaluating the histological severity of acute appendicitis in comparison with surgical and pathological findings. The CT images of 75 patients with surgically proven appendicitis, including 10 cases of catarrhal, 34 of phlegmonous, and 31 of gangrenous appendicitis, were retrospectively analyzed for the following five CT findings: hazy periappendiceal densities, enlarged appendix, increased enhancement of the appendiceal wall, increased enhancement of the periappendiceal intestinal wall, and deficiency of the appendiceal wall. By comparing all the CT findings and the pathological severity of appendicitis (catarrhal, phlegmonous, and gangrenous), the prevalence of the five CT findings was calculated for each pathological category. Abnormal CT findings were noted in only one case of catarrhal appendicitis. Increased enhancement of the appendiceal wall was observed in all ...

2001-08-01

473

Direct sub-nanometer scale electron microscopy analysis of anion incorporation to self-ordered anodic alumina layers  

International Nuclear Information System (INIS)

Research highlights: #-># Morphological and chemical characterization at atomic scale of porous alumina layers anodised in ordered regimes. #-># Characterization based on the use of FEG-SEM, STEM-HAADF, STEM-EELS and STEM-X-EDS. #-># Nanoscale distribution of P-, C- and S-bearing species in the pore wall. - Abstract: Ordered porous alumina layers prepared by two-step anodising in phosphoric, oxalic and sulphuric acids have been characterized at sub-nanometer scale using electron microscopy techniques. FEG-SEM and STEM-HAADF images allowed estimating the pore size, cell wall and pore wall thicknesses of the layers. Nanoanalytical characterization has been performed by STEM-EELS and STEM-X-EDS. Detailed features of the spatial distribution of anions in the pore wall of the films have been obtained. Maximum concentration of P-species occurs, approximately, at the middle of the pore ...

2010-11-01

474

Verification of maximum impact force for interim storage cask for the Fast Flux Testing Facility  

Energy Technology Data Exchange (ETDEWEB)

The objective of this paper is to perform an impact analysis of the Interim Storage Cask (ISC) of the Fast Flux Test Facility (FFTF) for a 4-ft end drop. The ISC is a concrete cask used to store spent nuclear fuels. The analysis is to justify the impact force calculated by General Atomics (General Atomics, 1994) using the ILMOD computer code. ILMOD determines the maximum force developed by the concrete crushing which occurs when the drop energy has been absorbed. The maximum force, multiplied by the dynamic load factor (DLF), was used to determine the maximum g-level on the cask during a 4-ft end drop accident onto the heavily reinforced FFTF Reactor Service Building`s concrete surface. For the analysis, this surface was assumed to be unyielding and the cask absorbed all the drop energy. This conservative assumption simplified the modeling used to qualify the cask`s structural integrity for this accident condition.

1996-06-01

475

The restauration of Sullivan mining site : a concept which considers the fauna; La restauration du site minier Sullivan : un concept a caracteres fauniques  

Energy Technology Data Exchange (ETDEWEB)

Mining operations took place at the Sullivan Mine, located at Sullivan, Abitibi, Quebec between 1930 and 1967 and generated large quantities of tailings. These tailings now represent a waste rock pile in the shape of a delta on the shore of De Montigny Lake. The area covers approximately 50 hectares. When the waste rock pile was first established, several terrestrial and aquatic ecosystems were lost forever. In addition, the very nature of the tailings, combined to the action of the wind and lake, further slow the natural site regeneration. The Ministere des Ressources naturelles du Quebec (Quebec Natural Resources Department) asked Les Consultants en Environnement Argus to prepare a site remediation plan to stimulate the natural regeneration of the ecosystems. It would enable the local fauna to resume its occupation of the territory, while ensuring its proper integration in the environment. The authors described in detail the proposed plan that addresses all the ...

2000-07-01

476

Sustainably economical operation of pumped storage power plants in a prospective market environment with increasing renewable energy generation; Nachhaltig wirtschaftlicher Einsatz von Pumpspeicherkraftwerken. Im zukuenftigen Marktumfeld mit steigender regenerativer Erzeugung  

Energy Technology Data Exchange (ETDEWEB)

Pumped storage plants participate in two structurally different markets: the market for scheduled energy (also known as spot market) and the reserve market. In order to achieve the best possible plant scheduling in terms of revenues the marketing of the available capacity from pumped storage plants needs to be optimised in both markets. Moreover, due to the abilities for providing reserve, pumped storage capacities within an existing power plant portfolio can lead to synergies for the whole portfolio. The optimised combined participation of a power plant in both spot and reserve market as well as the coherent portfolio effect are considered as particular challenges in energy economic assessments, e.g. in the light of investment decisions. Based on an extension project and in cooperation with RWTH Aachen University an optimised combined participation of a power plant in both markets was simulated for the first time, thereby applying an ...

2010-07-01

477

Solar energy in buildings; L'energie solaire dans le batiment  

Energy Technology Data Exchange (ETDEWEB)

This document gathers the presentations given at the first French national meetings of solar energy for the development of solar systems in buildings. The meeting was organized over two days. The first day comprises 4 workshops about: urbanism and planning, cultural acceptability of solar energy in buildings (the OPAC 38 housing association, point of view on an energy information point, the Freiburg (Germany) solar region and marketing examples), technical integration to the structure (Clipsol solutions), and economical criteria (compared impacts of R and D public photovoltaic programs (USA, Japan, Germany, France, Italy), financing of rehabilitation projects, global approach of solar photovoltaic energy, technical solutions and strategy of products development, why and how to make an economical analysis of solar energy applications in the building industry). The second day comprises a plenary session and a round table: global status of solar ...

2003-07-01

478

Short wave length and high qualification of free-electron laser  

International Nuclear Information System (INIS)

The oscillation experiment of free-electron laser (FEL) was carried at the wave length 488 nm. The space and time properties and power of FEL were investigated. The typical macropulse structure indicated the time interval 20 ms and the pulse width 2 to 3 ms. About 1 ns was necessary to build up FEL. The space distribution of FEL showed beautiful TEM_0_0 mode, TEM_0_1 and TEM_0_2 mode. On the basis of data, 39 #mu#W average power was calculated at 2.9 mA accumulated current per bunch by integrating each response of pixel of CCD camera. The peak power was 1.2 W. In the oscillator, FEL power was average 1.2 W, peak 38 kW. On the electron beam, the stability of head tail was controlled by 6-pole-Quadrupole-6-pole (SQS) system made by an experimental basis. We succeeded the single set test, setting up single set in the ring. The characteristic properties of electron beam evaporation mirror of photo oscillator were studied and then new type photo ...

1998-02-01

479

Respect distances. Rationale and means of computation  

Energy Technology Data Exchange (ETDEWEB)

Canisters with spent nuclear fuel can obviously not be located within deformation zones as this might jeopardise their long term mechanical stability and thereby constitute a potential hazard to the biosphere. Less apparent, but equally important, is the fact that earthquakes trigger reactivation, slip, of structures some distance from their hypocentres due to, among many other factors, stress redistribution. Fault slip across a deposition hole might damage the isolation capacity of the canister and thereby jeopardise the overall integrity of the barrier system. Therefore, the following question might be posed: What is the distance from a deformation zone beyond which a canister can be safely emplaced? This respect distance cannot be readily computed because, unknown future events aside, there are some complicated aspects that need to be addressed e.g. degree of conservatism, scale, our ability to model ice sheets and earthquakes, etc. In this ...

2004-12-01

480

Predictive Capability Maturity Model for computational modeling and simulation.  

Science.gov (United States)

The Predictive Capability Maturity Model (PCMM) is a new model that can be used to assess the level of maturity of computational modeling and simulation (M&S) efforts. The development of the model is based on both the authors experience and their analysis of similar investigations in the past. The perspective taken in this report is one of judging the usefulness of a predictive capability that relies on the numerical solution to partial differential equations to better inform and improve decision making. The review of past investigations, such as the Software Engineering Institute's Capability Maturity Model Integration and the National Aeronautics and Space Administration and Department of Defense Technology Readiness Levels, indicates that a more restricted, more interpretable method is needed to assess the maturity of an M&S effort. The PCMM addresses six contributing elements to M&S: (1) representation and geometric fidelity, (2) physics ...

2007-10-01

481

Power plants 2010. Lectures  

International Nuclear Information System (INIS)

The proceedings include the following lectures: Facing the challenges - new structures for electricity production. Renewable energies in Europe - chances and challenges. Nuclear outlook in the UK. Sustainable energy for Europe. Requirements of the market and the grid operator at the electricity production companies. Perspectives for the future energy production. Pumped storage plants - status and perspectives. Nuclear power/renewable energies -partners or opponents? New fossil fired power stations in Europe - status and perspectives. Nuclear energy: outlook for new build and lifetime extension in Europe. Biomass in the future European energy market - experiences for dong energy. Meeting the EU 20:20 renewable energy targets: the offshore challenges. DESERTEC: sustainable electricity for Europe, Middle East and North Africa. New power plants in Europe - a challenge for project and quality management. Consideration of safely in new build activities of power plants. ...

2010-09-22

482

Overview of Chuetsu-oki earthquake and evaluation of seismic safety  

International Nuclear Information System (INIS)

The Chuetsu-oki Earthquake strongly shook the Kashiwazaki-Kariwa Nuclear Power Station with the ground motions exceeding the design values. The incidents include a fire breakout of the Unit 3 transformer, a release of spilled water containing small amount of radioactive materials to the non-radiation control area and subsequently to the environment at Unit 6, and a release of radioactive material from the main turbine condenser through the main stack of Unit 7 due to the delay stooping the turbine gland steam ventilator by the operator in manually, while every unit in operation was safety shutdown in the automatic mode ensuring the three fundamental safety functions of (a) reactivity control, (b) removal of heat from the core and (c) confinement of radioactive materials. Following integrity evaluation and performance testing of the overall plant, seismic safety of buildings, structures, equipment and pipelines on the basis of the basic ...

2010-07-01

483

Monitoring challenges and innovative ideas  

Energy Technology Data Exchange (ETDEWEB)

Monitoring programs are difficult to design even when they focus on specific problems. Ecosystems are complex, and it is often impossible to predetermine what aspects of system structure or dynamics will respond to a specific insult. It is equally difficult to interpret whether a response is a stabilizing compensatory mechanism or a real loss of capacity to maintain the ecosystem. The problems are compounded in a broad monitoring program designed to assess ecosystem health'' at regional and continental scales. It is challenging in the extreme to monitor ecosystem response, at any scale, to past insults as well as an unknown future array of impacts. The present paper will examine some of the fundamental issues and challenges raised by large-scale monitoring efforts. The challenges will serve as a framework and as an excuse to discuss several important topics in more detail. Following the discussion of challenges, we suggest some basic innovations ...

1990-01-01

484

Lithospheric evolution in response to triple junction migration: A program to obtain seismic images of the MTJ region  

Energy Technology Data Exchange (ETDEWEB)

The authors will be conducting an integrated seismic experiment to image the structure of the crust and upper mantle of northern California immediately before and after passage of the Mendocino Triple Junction. The purpose of this representation is to describe the project to other scientists interested in geological and geophysical processes in this region and to solicit input relevant to detailed siting of the funded seismic profiles. The experiment encompasses two field seasons: onshore seismic refraction/wide angle reflection data acquisition along three long profiles scheduled for late summer, 1993; and MCS deep crustal seismic reflection data acquisition accompanied by simultaneous large aperture recording using both ocean bottom and onshore seismographs, tentatively scheduled for summer, 1994. This study represents a component of a long-term, multi-disciplinary effort on the part of many investigators to exploit this well defined system ...

1993-04-01

485

Is loop quantization in cosmology unique?  

CERN Document Server

We re-examine the process of loop quantization for flat isotropic models in cosmology. In particular, we contrast different inequivalent `loop quantizations' of these simple models through their respective successes and limitations and assess whether they can lead to any viable physical description. We propose three simple requirements which any such admissible quantum model should satisfy: i) independence from any auxiliary structure, such as a fiducial interval/cell introduced to define the phase space when integrating over non-compact manifolds; ii) existence of a well defined classical limit and iii) provide a sensible "Planck scale" where quantum gravitational effects become manifest. We show that even when it may seem that one can have several possible loop quantizations, these physical requirements considerably narrow down the consistent choices. Apart for the so called improved dynamics of LQC, none of the other available inequivalent ...

2008-01-01

486

Interpolation between Airy and Poisson statistics for unitary chiral non-Hermitian random matrix ensembles  

CERN Document Server

We consider a family of chiral non-Hermitian Gaussian random matrices in the unitarily invariant symmetry class. The eigenvalue distribution in this model is expressed in terms of Laguerre polynomials in the complex plane. These are orthogonal with respect to a non-Gaussian weight including a modified Bessel function of the second kind, and we give an elementary proof for this. In the large $n$ limit, the eigenvalue statistics at the spectral edge close to the real axis are described by the same family of kernels interpolating between Airy and Poisson that was recently found by one of the authors for the elliptic Ginibre ensemble. We conclude that this scaling limit is universal, appearing for two different non-Hermitian random matrix ensembles with unitary symmetry. As a second result we give an equivalent form for the interpolating Airy kernel in terms of a single real integral, similar to representations for the asymptotic kernel in the bulk and at the hard edge ...

2010-01-01

487

Integrating preventive maintenance, predictive maintenance, and maintenance technical support  

Energy Technology Data Exchange (ETDEWEB)

The fundamental tasks of the Oak Ridge Y-12 Plant maintenance operations are planning, scheduling, executing, postmaintenance testing, completing the maintenance job, and supporting these activities with administrative and technical assistance. The Department of Energy (DOE) ``Maintenance Management Program`` guidelines require that we use a graded approach for applying formality and documentation to these maintenance operations. The most-rigorous controls should be placed on maintaining the most-vital systems, structures, and components (SSCs). We must understand risk assessments in order to evaluate which SSCs are most vital. The product of this assessment process is a well-developed understanding of where to apply the most rigor, formality, and documentation. Once we have determined where, we must determine how to apply maintenance so as to mitigate risk. Fundamental to determining how to apply it is an understanding of the main difference between proactive and ...

1992-08-06

488

Improved recovery demonstration for Williston Basin carbonates. Quarterly report, January 1, 1996--March 31, 1996  

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in- place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional and multi-component seismic area is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended- reach jetting lance and other ultra-short radius lateral technologies. Improved completion efficiency, additional wells at closer spacings better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes. Technical progress is ...

1996-07-01

489

HAMMER FY 1996 Multi-Year Program Plan: WBS {number_sign}8.2  

Energy Technology Data Exchange (ETDEWEB)

The Hazardous Material Management and Emergency Response Training and Education Center -- known simply as HAMMER -- is being developed to assist the US Department of Energy (DOE) and others dedicated to improving worker health, safety and productivity. HAMMER is a training and education program for hazardous material, waste management, and emergency response workers. HAMMER is managed by the DOE Richland Operations Office under Work Breakdown Structure (8.2). The 1996 Multi-Year Program Plan (MYPP) includes the Execution Year data and provides the information for Programmatic Fiscal Year Site Management System Execution Baseline, as well as the detailed work plan for performance evaluation of the authorized work. The MYPP incorporates various planning methodologies to define the program and provides essential program integration, and a fully developed technical, cost, and schedule baseline. The MYPP will be utilized by WHC Program and ...

1995-09-01

490

GaInP high-power lasers; GaInP Hochleistungslaser  

Energy Technology Data Exchange (ETDEWEB)

The following work deals with the realization, characterization and modeling of GaInP / AlGaInP high power semiconductor laser diodes in the visible wavelength range. In addition to the exploration and optimization of efficiency, temperature stability and maximum output power of multi-mode lasers especially methods for longitudinal and lateral mode stabilization of high power laser diodes have been investigated. Although often the focus of optimization is on the threshold current density, in this work the performance of the laser diode for an operation point around 1 Watt under continous wave operation is regarded as the figure of merit. It turns out that low carrier densities are key for an efficient reduction of the heterobarrier leakage currents. In addition, large optical cavity structures with low internal losses enable high external quantum efficiencies even for long cavities. Finally high laser effiency as well as an efficient cooling leads to a reduced ...

2002-07-01

491

GaInP high-power lasers  

International Nuclear Information System (INIS)

The following work deals with the realization, characterization and modeling of GaInP / AlGaInP high power semiconductor laser diodes in the visible wavelength range. In addition to the exploration and optimization of efficiency, temperature stability and maximum output power of multi-mode lasers especially methods for longitudinal and lateral mode stabilization of high power laser diodes have been investigated. Although often the focus of optimization is on the threshold current density, in this work the performance of the laser diode for an operation point around 1 Watt under continous wave operation is regarded as the figure of merit. It turns out that low carrier densities are key for an efficient reduction of the heterobarrier leakage currents. In addition, large optical cavity structures with low internal losses enable high external quantum efficiencies even for long cavities. Finally high laser effiency as well as an efficient cooling leads to a reduced ...

492

Existence and equilibration of global weak solutions to finitely extensible nonlinear bead-spring chain models for dilute polymers  

CERN Document Server

We show the existence of global-in-time weak solutions to a general class of coupled FENE-type bead-spring chain models that arise from the kinetic theory of dilute solutions of polymeric liquids with noninteracting polymer chains. The class of models involves the unsteady incompressible Navier-Stokes equations in a bounded domain in two or three space dimensions for the velocity and the pressure of the fluid, with an elastic extra-stress tensor appearing on the right-hand side in the momentum equation. The extra-stress tensor stems from the random movement of the polymer chains and is defined by the Kramers expression through the associated probability density function that satisfies a Fokker-Planck-type parabolic equation, a crucial feature of which is the presence of a center-of-mass diffusion term. We require no structural assumptions on the drag term in the Fokker-Planck equation; in particular, the drag term need not be corotational. With a ...

2010-01-01

493

Electrical biasing and voltage contrast imaging in a focused ion beam system  

Energy Technology Data Exchange (ETDEWEB)

We present two new techniques that enhance conventional focused ion beam (FIB) system capabilities for integrated circuit (IC) analysis: in situ electrical biasing and voltage contrast imaging. We have used in situ electrical biasing to enable a number of advanced failure analysis applications including (1) real time evaluation of device electrical behavior during milling and deposition, (2) verification of IC functional modifications without removal from the FIB system, and (3) ultraprecision control for cross sectioning of deep submicron structures, such as programmed amorphous silicon antifuses. We have also developed FIB system voltage contrast imaging that can be used for a variety of failure analysis applications. The use of passive voltage contrast imaging for defect localization and for navigation on planarized devices will be illustrated. In addition, we describe new, biased voltage contrast imaging techniques and provide examples of ...

1995-09-01

494

Effect of irradiation on bone remodelling and the structural integrity of the vertebral column. Doctoral thesis  

Energy Technology Data Exchange (ETDEWEB)

The effects of therapeutic levels of radiation on the axial properties of the primate vertebral column were studied. Seven male rhesus monkeys (Macaca mulatta) were irradiated with a single does of 1300 cGy to the specific lumbar vertebrae of L2, L3, and L4. Three additional animals served as controls. Radiographs were taken before the radiation treatment and just prior to sacrifice to determine density changes in the bone. The animal subjects were sacrificed 105 days following the radiation exposure. Biomechanical testing was completed on lumbar levels 2 and 3 to identify changes in strength characteristics following radiation treatment. Histomorphometric analysis of lumbar vertebrae level 4 was completed to identify volume and surface density changes as well as cellular changes. Tetracycline, dicarbomethylaminomethyl fluorescein (DCAF), and xylenol orange were used as bone labeling agents to aid in the histomorphometry and to obtain dynamic parameter changes.

1990-01-01

495

Dynamic complexities for prey-dependent consumption integrated pest management models with impulsive effects  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we consider the prey-dependent consumption predator-prey (natural enemy-pest) models with age structure for the predator, immature and mature natural enemies are released and pesticide is applied impulsively. We prove that, when the impulsive period is no longer than some threshold, the pest-eradication solution is globally asymptotically stable, or say, the pest population can be eradicated totally. But from the point of ecological balance and saving resources, we only need to control the pest population under the economic threshold level instead of eradicating it totally, so we further prove that, when the impulsive period is longer than the threshold, pest population and natural enemy population can coexist, i.e., the system is uniformly permanent. Considering population communities always are imbedded in periodically varying environments, and the parameters in ecosystem models may oscillate simultaneously with the periodically varying ...

2006-07-15

496

Coordination of air pollution abatement. Ilmansuojeluohjelmien yhteensovittaminen  

Energy Technology Data Exchange (ETDEWEB)

Finland has set up several national air pollution control programmes in order to implement international conventions. As a rule these programmes have focused on one pollutant. The national second carbon dioxide commission is at present working on a new programme to curb carbon dioxide emissions, and this will unavoidably affect other programmes, too. This study presents the existing programmes and their respective implementation costs. The aim has been to focus on the interaction between different air pollution combatting measures and the possibilities of setting priorities on a cost basis. The main result is that it will be difficult to integrate overall aims for general welfare and subsequent energy consumption with environmental considerations, especially in air pollution control. If the increase in energy generation follows current scenarios, the costs for air pollution abatement measures will require a considerable portion of the increase in the national ...

1992-01-01