Science.gov (United States)

Graft copolymers of methyl methacrylate and biodegradable, biocompatible bacterial poly([R]-3-hydroxybutyrate) (PHB) blocks were synthesized and evaluated as possible constituents in acrylic bone cements for use in orthopaedic applications. The copolymers were produced by conventional free radical copolymerization and incorporated in one commercially available acrylic bone cement brand, Antibiotic Simplex (AKZ). Cements with formulations containing 6.7 and 13.5 wt % of PMMA-graft-PHB were prepared. The morphology of the graft copolymer particles was suggested to influence the ability of the modified cement to be processed. Formulations containing more than about 20 wt % of the graft copolymer resulted in cement doughs that, both after first preparation and several hours later, were either sandy or soft spongy in texture and, thus, would be unacceptable for use in orthopaedic ...

International Nuclear Information System (INIS)

This review begins with an historical account of biomaterials applications followed by a concise description of the phenomena taking place between the living tissues and non-living materials containing them. After describing the requirements for biodegradability and the mechanisms involved, a thorough literature survey of such polymers is presented. In the end a very short review of the work done in this area by the authors in recent years is given, including: the synthesis of a wide variety of biodegradable di-and tri-block copolymers, preparation of microparticles; stealth-and immuno-liposomes; dendrosomes and polymersomes; and some of their applications in drug and gene delivery.

Energy Technology Data Exchange (ETDEWEB)

The presence of water in export coals increases transport and handling costs. Coarse (+0.5 mm) coal constitutes the majority of the product, and small changes in its final moisture content will have a significant effect on overall product moisture. An on-line moisture monitor was installed on a product belt immediately after a coarse coal centrifuge to continuously measure the moisture content of the coal from a single centrifuge. Basic studies were also conducted with a laboratory centrifuge specifically designed to characterize various coarse coal samples in terms of their water retention capacity. The moisture of the coarse coal (typically 6 to 9%) was found to vary by at least 1% at a particular plant, and by a number of percentage points between plants. An empirical model has been developed which can explain about 80% of the moisture variation from the 25 samples investigated. The rank of the coals ranged from 0.7 to 1.65% mean reflectance. The model identified four principle ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Binding of Cd/sup 2 +/ ions in aqueous solutions of statistical copolymers of acrylamide with cadmium acrylate with different content of ionogenic groups in copolymers was investigated by polarography, conductometry, viscometry and dialysis. It is shown that the degree of binding of Cd/sup 2 +/ ions increases with increasing of the content of ionogenic groups in the copolymer and with decreasing of ionic strength of the solution. The values of the degree of binding of Cd/sup 2 +/ ions obtained by polarography and dialysis show satisfactory agreement.

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

The authors present the results of an investigation of the effect of gamma radiation on the properties of low-molecular moulded polymethyl methacrylates (molecular weight distribution, physicomechanical properties, resistance to the effects of aqueous media and physiological solution) in the form of copolymers of methyl methacrylate with methyl (MA) or butyl acrylate (BA) with the brand names Dacryl-4B, Dacryl-2M and Dacryl-4M (4% BA; 2 and 4% MA respectively) having a molecular weight of around 10"5. For comparison, block polymethyl methacrylate with a molecular weight of 3 x 10"6 was used. The results of experiments on the ageing of unirradiated and irradiated specimens in a heated store-room (t = 10 - 20"0C) and at high temperatures (90"0C) are also given. It is shown that irradiation with doses of 2.5-20 Mrad leads to radiolysis of the above copolymers, accompanied by destructive processes. Evidence of this is an ...

International Nuclear Information System (INIS)

The purpose of this study was to reveal the mechanism of wafer touch polishing using a high purity colloidal silica slurry containing organic surfactants such as hydroxyl-ethyl cellulose. The effect of the surfactant concentration on wafer touch polishing was studied to improve the roughness of wafer surfaces after polishing. The haze level and the micro-roughness decreased with decreasing surfactant concentration.

Energy Technology Data Exchange (ETDEWEB)

Amphiphilic block copolymers are synthesized by sulfonation of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) using acetyl sulfate, and are blended with poly(vinylidene fluoride) (PVDF) to prepare a new proton exchange membrane, in which PMMA is miscible with PVDF. The morphology and the transport properties of the membranes are investigated as functions of the degree of sulfonation as well as the blend ratio. Notable transition of phase-separated morphology is observed as the PVDF content of the blend is increased. Both the proton conductivity and the ion-exchange capacity (IEC) of the membrane increase with increasing the degree of sulfonation of PS-b-PMMA, and they are also enhanced as the phase-separated domains of blend membrane are well-ordered. Unlike the Nafion membrane, the proton conductivity of the blend membrane increases up to 90 C, indicating the blend membrane shows better thermal stability than the Nafion membrane. (author)

Energy Technology Data Exchange (ETDEWEB)

Cited are the results of physico-chemical studies and industrial tests of a copolymer of methacrylic acid and diethylammonium salt, used for limiting the influx of stratum waters into a well.

Science.gov (United States)

... MECHANICAL PROPERTIES, *COPOLYMERS, *SOFT TISSUES, *GELS, *BIOMIMETICS, ISOPRENE, WOUND BALLISTICS, STYRENE PLASTICS ...

Energy Technology Data Exchange (ETDEWEB)

A series of N-carbazolyl-substituted silane homo- and copolymers has been prepared by Wurtz coupling. Doping with iodine on these copolymer films increases the electrical conductivity to the range 10{sup -6}-10{sup -3} S cm{sup -1}. The conductivity depends strongly on the composition of the copolymer; it reaches the maximum value for N-carbazolyl-substituted silane homopolymer. The effects of carbazolyl group on conductivity and charge transport mechanisms in the polymer are discussed. (orig.)

Energy Technology Data Exchange (ETDEWEB)

Sulfuric acid hydrogen peroxide mixtures (SPM) are commonly used in the semiconductor industry to remove organic contaminants from wafer surfaces. This viscous solution is very difficult to rinse off water surfaces. Various rinsing conditions were tested and the resulting residual acid left on the water surface was measured. Particle growth resulting from incomplete rinse is correlated with the amount of sulfur on the wafer surface measured by Time of Flight Secondary Ion Mass Spectroscopy (TOF-SIMS). The amount of sulfur on the wafer structure after the rinse step is strongly affected by the wafer film type and contact angle prior to the SPM clean.

Energy Technology Data Exchange (ETDEWEB)

A series of copolymers based on the cellulose acetate/propionate-g.co-acrylic acid system has been prepared under radiation-induced control. These copolymers have been assessed for their water-retention capacity both in an unmodified state and after ''decrystallization'' or ''neutralization'' treatments. The grafting of acrylic acid onto the cellulose acetate/propionate had little effect on the water retention power of the cellulose acetate/propionate. However, improvements to the water retentivity was obtained after ''decrystallization'' procedures had been carried out on the copolymers using selected alkali metal salts with methanol as the continuous medium. The water-retentivity of the copolymers increased with increase in the extent of grafting, though the effect is less pronounced at high ...

International Nuclear Information System (INIS)

Nanowires of copolymers film based on aniline and 1-amino-2-naphthol-4-sulphonic acid were electrochemically synthesized on the iron electrode by cyclic voltammetry using oxalic acid as a supporting electrolyte. Protective properties of copolymer film on the iron surface in 1.0 M HCl solution was investigated by chronoamperometry, potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results showed that the copolymer film showed the significant shifting in the corrosion potential and greater charge transfer resistance. Moreover, the copolymer showed the larger degree of surface coverage onto the iron surface, reflecting the higher protection for corrosion of the iron in acidic medium. In addition, the film constitutes a physical as well as a chemical barrier layer due to the presence of -OH and -NH groups in ANSA unit, which provides passivity protection in polymer ...

British Library Electronic Table of Contents (United Kingdom)

Poly(methyl methacrylate), PMMA, scrap generated during the casting process for PMMA cast sheet is an industrial waste stream, which has a high impact on the PMMA production cost and environment. This paper presents an alternative way to reduce the processing cost of PMMA cast sheet and decrease industrial waste by using styrene (S) as a co-monomer with methyl methacrylate (MMA) monomer, in conjunction with recycling of PMMA scrap in the S-MMA copolymer cast sheet process. The influence of factors, such as the concentrations of S and PMMA scrap, on the preparation of S-MMA copolymer cast sheet mixed with PMMA scrap was investigated. The characterization of basic copolymer composition, the physical, and the mechanical properties of the final products were examined. The results show that it ...

Energy Technology Data Exchange (ETDEWEB)

Sulfuric acid hydrogen peroxide mixtures (SPM) are commonly used in the semiconductor industry to remove organic contaminants from wafer surfaces. This viscous solution is very difficult to rinse off wafer surfaces. Various rinsing conditions were tested and the resulting residual contamination on the wafer surface was measured. The addition of small amounts of a chemical base such as ammonium hydroxide to the rinse water has been found to be effective in reducing the surface concentration of sulfur and also mitigates the particle growth that occurs on SPM cleaned wafers. The volume of room temperature water required to rinse these wafers is also significantly reduced.

Science.gov (United States)

Copolymers of a 1,2 epoxy alkane and a cyclic carboxylate compound of the class consisting of dicarboxylic acid anhydrides, preferably maleic anhydride or a hydrocarbyl substituted succinic anhydride and a beta lactone, said copolymers having C/sub 10/ to C/sub 50/, preferably C/sub 20/ to C/sub 40/, linear, pendant hydrocarbon chains are flow improvers in residual and crude oils.

Science.gov (United States)

... and facilities; the physical processing of materials into products; and processes associated with ... area of bulk silicon prod! uction as wafer material has been omitted, in keeping with current ...

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the interaction of (PEG-co-P(FA/SC)-co-PEG) triblock copolymer with bovine and human insulins was carried out using isothermal titration calorimetry (ITC), circular dichroism (CD), and fluorescence spectroscopy. ITC data show that the copolymer has a low affinity for both proteins, with an association constant of about 7?9?103?M ?1. Results also show that binding is enthalpically driven, and disfavored by conformational entropy. CD spectroscopy studies reveal a small increase in the helical content and a decrease in ?-structure as well as random coil in both proteins. Acrylamide quenching experiments display reduced accessibility of tyrosines, while intrinsic fluorescence spectra show lower tyrosine emission. Furthermore, thermal unfolding experiments, studied by far...

Energy Technology Data Exchange (ETDEWEB)

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

Energy Technology Data Exchange (ETDEWEB)

This patent describes an aqueous clay containing drilling fluid having present in an amount sufficient to reduce fluid loss of the drilling fluid, a copolymer of (1) from about 80% to about 98% by weight of acrylic acid and (2) from about 2% to about 20% by weight of itaconic acid. The copolymer has a weight average molecular weight of between about 50,000 to about 1,000,000, being in its free acid or partially or completely neutralized salt form and being at least water dispersible.

Energy Technology Data Exchange (ETDEWEB)

Short communication. 3 refs.

Science.gov (United States)

PMID:15922238

Science.gov (United States)

The PVSCAN is an instrument designed to characterize silicon solar cell materials and devices. It performs a host of measurements that yield spatial maps of dislocation density, grain distribution, reflectance, and photoresponses from near-junction and the bulk of a solar cell.

Science.gov (United States)

In this contract, Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. The tasks comprising these investigations are outlined. Four new batches of solar cells were processed, in addition to several test runs on wafers, using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. A one watt laser power gave an electroplated linewidth of 50 microns , while at 8 watts the line width was 90 microns.

Energy Technology Data Exchange (ETDEWEB)

Components of various forest and agricultural residue biomass-including the polyphenolic compounds-were converted into aqueous solution and/or suspension by extraction and digestion. Some biomass components reacted vigorously under alkaline catalysis with formaldehyde and initially showed a high degree of exothermic reaction; however, other components did not react as vigorously under these conditions, indicating that different biomass materials require different methods to obtain optimum reactivity for the copolymerization with phenol. Our primary goal is to develop adhesives capable of producing acceptable bond quality, as determined by the wood products industries` standards, under a reasonable range of gluing conditions. Copolymer resins of phenol, formaldehyde, and biomass components were synthesized and evaluated for gluability of bonding exterior grade structural replaced with chemicals derived from peanut hulls, pecan shell flour, pecan pith, southern pine ...

International Nuclear Information System (INIS)

Here we reported a two-step procedure for preparing a novel polymeric based solid-solid phase change heat storage material. Firstly, a copolymer monomer containing a polyethylene glycol monomethyl ether (MPEG) phase change unit and a vinyl unit was synthesized via the modification of hydrogen group of MPEG. Secondly, by copolymerization of the copolymer monomer and phenyl ethylene, a novel polymeric based solid-solid phase change heat storage material was prepared. The composition, structure and properties of the novel polymeric based solid-solid phase change material were characterized by IR, "1H NMR, DSC, WAXD, and POM, respectively. The results show that the novel polymeric based solid-solid phase change material possesses of excellent crystal properties and high phase change enthalpy.

International Nuclear Information System (INIS)

As an engineered barrier system in the geological disposal of high-level waste, multibarrier system is considered. Multibarrier system consists of the vitrified waste, the overpack and the buffer. Bentonite is one of the potential material as the buffer because of its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. As the construction technology of the buffer, the block installation method and in-situ compaction method, etc, are being investigated. The block installation method is to emplace the buffer blocks manufactured in advance at the ground facility, and construction processes of the block installation method at the underground will be simplified compared with the in-situ compaction method. However, the ...

Energy Technology Data Exchange (ETDEWEB)

Three blocks of non-welded tuff, one nominally one cubic foot (trial block) and the other two, nominally one cubic metre (1 m{sup 3}), were excavated from the Busted Butte Test Facility on the Nevada Test Site and transported to the Atomic Energy of Canada Limited Whiteshell Laboratories in Pinawa, Manitoba. The trial block and one of the 1-m{sup 3} blocks were used for unsaturated flow experiments. The remaining 1-m{sup 3} block is being used for saturated flow experiments and will be reported on separately. After a vertical flow of synthetic transport solution was set up under unsaturated conditions, a suite of conservative and chemically reactive radionuclide tracers was injected at volumetric flow rates of 20 mL/hr in the trial block, and 10 mL/hr in the 1-m{sup 3} block. The duration of the migration experiment in the trial ...

UK PubMed Central (United Kingdom)

The study of blocking factors requires in vitro assay of cell mediated immunity that parallels the in vivo response. By microcytotoxicity testing, progressor and immune peripheral blood lymphocytes...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin ...

International Nuclear Information System (INIS)

Short communication. 3 refs.

Science.gov (United States)

... reverse aeb 9 nescesmsy amI identify by block number) Provides procedures for evaluating metal, consumable, and combustible cartridge cases. ...

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)

Energy Technology Data Exchange (ETDEWEB)

Low residual stress silicon oxynitride thin films are investigated for use as a replacement for silicon dioxide (SiO{sub 2}) as sacrificial layer in surface micromachined microelectrical-mechanical systems (MEMS). It is observed that the level of residual stress in oxynitrides is a function of the nitrogen content in the film. MEMS film stacks are prepared using both SiO{sub 2} and oxynitride sacrificial layers. Wafer bow measurements indicate that wafers processed with oxynitride release layers are significantly flatter. Polycrystalline Si (poly-Si) cantilevers fabricated under the same conditions are observed to be flatter when processed with oxynitride rather than SiO{sub 2} sacrificial layers. These results are attributed to the lower post-processing residual stress of oxynitride compared to SiO{sub 2} and reduced thermal mismatch to poly-Si.

British Library Electronic Table of Contents (United Kingdom)

Herein, we demonstrate the structure of the PS colloidal crystals which were fabricated on the hydrophilic/hydrophobic Si wafers by a spin-coating technique. Monodisperse PS colloids are spin-coated onto self-assembled monolayers of 3-(aminopropyl)triethoxysilane and propyltrimethoxysilane coated Si wafers. PS spheres organized as ordered close-packed face-centered cubic structure with (111) planes on the hydrophilic surface while they gathered without the crystal structure on the hydrophobic surface. This paper also reports a simple and rapid method to fabricate the close-packed structure of hollow TiO2 spheres. The colloidal crystal of TiO2 hollow spheres was prepared using the PS sphere template on the hydrophobic surface. The mechanism for the growing multilayers of self-assembled PS p...

Science.gov (United States)

We report the characteristics of visible vertical cavity surface emitting laser diodes. Wafers are grown such that the Fabry--Perot resonance wavelength changes with position from 690 to 620 nm, overlapping to varying degrees with the [ital n]=1 and [ital n]=2 quantum well gain peaks at [similar to]670 and 650 nm. Gain guided devices are tested across the entire wafer, and pulsed room temperature lasing is observed from 634.6 to 663.2 nm. Our results suggest that gain contributions from the second quantized state are required to overcome high cavity losses in order to achieve lasing.

Energy Technology Data Exchange (ETDEWEB)

This paper describes a newly developed software for manifold block design. Manifold block has become indispensable as an important component part to hydraulic systems since the 1970 {prime} s. However, its design is complicated and difficult. The reasons are firstly that hydraulic circuits have to be densely placed and secondary there is no means to correct a failure in the design or manufacture. Considering these points, the experiments of design engineers and the habitual design processes are analyzed, and a support system for manifold block design was developed by using a super-mini computer. With this system, the correctness of a design became to be proved. The software is easy to operate, and it can retrieve past design data, and it is extendible to the production line. 4 refs., 7 figs., 4 tabs.

Energy Technology Data Exchange (ETDEWEB)

A method of grafting lignin-containing materials is now known which allows 1-phenylethylene or 4-methyl-2-oxy-3-oxopent-4-ene graft copolymers of wood to be quantitatively made. Graft copolymer is formed by conducting a free-radical polymerization with 1-phenylethene in nitrogen-saturated, organic or aqueous/organic solvent containing a lignin source, calcium chloride, and a hydroperoxide. Grafting changes solubility and surface properties of the wood. The lignin-containing materials grafted are unbleached wood pulps produced by chemical, thermal, and mechanical pulping. Grafting wood pulp produces a wood-reinforced, thermoplastic composite. When a particular plastic is to be blended with wood, we react the wood with the monomer used to make that plastic. This creates a hydrophobic surface of the plastic on the wood. This plastic coating can readily bond to the continuous plastic phase. The products of this grafting reaction are thermoplastic ...

Science.gov (United States)

Coir fibers received three treatments, namely washing with water, alkali treatment (mercerization) and bleaching. Treated fibers were incorporated in starch/ethylene vinyl alcohol copolymers (EVOH) blends. Mechanical and thermal properties of starch/EVOH/coir biocomposites were evaluated. Fiber morphology and the fiber/matrix interface were further characterized by scanning electron microscopy (SEM). All treatments produced surface modifications and improved the thermal stability of the fibers and consequently of the composites. The best results were obtained for mercerized fibers where the tensile strength was increased by about 53% as compared to the composites with untreated fibers, and about 33.3% as compared to the composites without fibers. The mercerization improved fiber-matrix adhesion, allowing an efficient stress transfer from the matrix to the fibers. The increased adhesion between fiber and matrix was also observed by SEM. Treatment with water also ...

International Nuclear Information System (INIS)

A total dose hardening treatment is applied to SIMOX buried oxides. Total ionizing dose radiation testing is performed on fully-depleted transistors fabricated on both hardened and non-hardened substrates. At 200 krads x-ray dose, the front gate shift is reduced from -0.7 to -0.2 V for FETs built on the hardened wafers.

Energy Technology Data Exchange (ETDEWEB)

The invention relates to a pulsed laser ablation method of metals and/or dielectric films from the surface of a wafer, printed circuit board or a hybrid substrate. By utilizing a high-energy ultra-short pulses of laser light, such a method can be used to manufacture electronic circuits and/or electro-mechanical assemblies without affecting the material adjacent to the ablation zone.

International Nuclear Information System (INIS)

The influence of RTA (Rapid Thermal Anneal) treatment on MOS radiation hardness is demonstrated and compared with classical furnace treatment. In the case of the RTA, the oxide trapped charge is found to depend on: (i) the anneal temperature as expected, data are in good agreement with a recently developed model of oxygen out-diffusion; (ii) the location across the wafer with a radial dependence, results could be related to stress induced by thermal gradient.

International Nuclear Information System (INIS)

The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, developed an alignment strategy to specify elemental depth profiling in vertical sidewall layers on structured wafers. For this purpose, PTB's irradiation chamber for 200 mm and 300 mm silicon wafers was used to combine total-reflection X-ray fluorescence (TXRF) and grazing incidence XRF (GIXRF) techniques by employing monochromatized undulator radiation of the BESSY II electron storage ring. 3-D test structures were fabricated to develop an optimal alignment strategy allowing for depth profiling in such nanolayers. The test structures consisted of silicon bars with widths/spacings either in the ?m or in the nm range. In order to be able to differentiate the sidewalls more easily from the remainder of the structures, they were provided with an additional silicon nitride layer. Four structure types of different bar width and density parameters on two 200 mm ...

Energy Technology Data Exchange (ETDEWEB)

In a recent paper, Lowry (1981) described an architecture for a computer vision rectangular processor array that is suitable for VLSI implementation. In this paper the authors review that architecture, discuss extensions to it and present results of an array simulator applied to vision algorithms. They also present an algorithm for re-routing an array with bad processors into a working subset of the array, making it feasible to implement a large array on one wafer-sized chip. 7 references.

International Nuclear Information System (INIS)

Three blocks of non-welded tuff, one nominally one cubic foot (trial block) in volume and the other two, nominally one cubic meter (1 m3) in volume, were excavated from the Busted Butte Test Facility on the Nevada Test Site in 1999 and transported to the Atomic Energy of Canada Limited Whiteshell Laboratories in Pinawa, Manitoba. The trial block and one of the 1-m3 blocks were used for radionuclide migration experiments under unsaturated conditions; the remaining 1-m3 block was used for similar migration experiments under saturated conditions. After a vertical flow of synthetic transport solution was set up under unsaturated conditions, a suite of conservative and chemically reactive radionuclide tracers was injected at volumetric flow rates of 20 mL/hr in the trial block, and 10 mL/hr in two locations on the upper surface of the 1-m3 block. ...

International Nuclear Information System (INIS)

The design of the absorber blocks for internal and external dumping of the SPS proton beam is discussed. In addition, the external target stations for slow and fast extracted proton beams are described.

UK PubMed Central (United Kingdom)

BackgroundNonsteroidal anti-inflammatory drugs are commonly used to treat postoperative and chronic pain. Animal studies suggest these drugs act in part by blocking...Full Text Available

Science.gov (United States)

... Those functions are fundamental routines to build a power model for more complex circuits or functional blocks. ... 21 of 54 6. Memory Power Model ...

Science.gov (United States)

the Missionaries and Cannibals, Fool's Disk, the Blocks World. and the 8-Puzzle. Also ...... place the sets of missionaries and cannibals by ob- ...

Science.gov (United States)

9-foot 9-inch blocks of concrete with asphaltic-filled expansion joints. The concrete was placed on 4 to 6 inches of gravel or #4 stone. ...

Science.gov (United States)

... irispectors to operate or Soviet territory. They exr-essed this reluctarice ir interniat ionai law terms, claimirig that inspect ior act ivit ies ...

CERN Document Server

How far can a stack of $n$ identical blocks be made to hang over the edge of a table? The question dates back to at least the middle of the 19th century and the answer to it was widely believed to be of order $\\log n$. Recently, Paterson and Zwick constructed $n$-block stacks with overhangs of order $n^{1/3}$, exponentially better than previously thought possible. We show here that order $n^{1/3}$ is indeed best possible, resolving the long-standing overhang problem up to a constant factor.

British Library Electronic Table of Contents (United Kingdom)

Information technology plays an important role in medicine because of the advanced decision support systems (DSS) it can provide. We provide an overview of the building blocks necessary for a medical decision support system and introduce seven research articles in this special issue that describe the development and evaluation of individual medical DSS building blocks or complete medical DSS.

International Nuclear Information System (INIS)

High-power arc lamp design has enabled ultrahigh-temperature (UHT) annealing as an alternative to conventional rapid thermal processing (RTP) for ultrashallow junction formation. The time duration of the UHT annealing technique is significantly reduced from those obtained through conventional RTP. This difference in time may offer the ability to maintain a highly activated ultrashallow junction without being subjected to transient enhanced diffusion (TED), which is typically observed during postimplant thermal processing. In this study, two 200-mm (100) n-type Czochralski-grown Si wafers were preamorphized with either a 48- or a 5-keV Ge"+ implant to 5x10"1"4 cm"2, and subsequently implanted with 3-keV BF_2"+ molecular ions to 6x10"1"4 cm"2. The wafers were sectioned and annealed under various conditions in order to investigate the effects of the UHT annealing technique on the resulting junction characteristics. The main point of the paper is ...

CERN Document Server

Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO sub 2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to levels that must be improved before new processes can be put into production. It should be noted that much of this metal contamination occurs during the wet chemical etching and rinsing steps required for the manufacture of integrated circuits and industry is actively developing new processes that have already brought the metal contamination to levels beyond the measurement capabilities of conventional analytical techniques. The measurement of these extremely low contamination levels has required the use of synchrotron radiation total reflection X-ray fluorescence (SR-TXRF) ...

CERN Document Server

A new monolithic semi-insulating (SI) GaAs sensor design for X-ray imaging applications between 10-100keV has been proposed. Monolithic pixel detectors offer a number of advantages over hybrid bump-bonded detectors, such as high device yield, low costs and are easier to produce large scale arrays. In this thesis, an investigation is made of the use of a SI GaAs wafer as both a detector element and substrate for the epitaxially grown High Electron Mobility Transistors (HEMTs). The design of the HEMT transistors, optimised for this application, were produced with the aid of the Silvaco 'Virtual Wafer Fab' simulation package. It was determined that the device characteristics would consist of a small positive threshold voltage, a low off-state drain current and high transconductance. The final HEMT transistor design, that would be integrated to a pixel detector, had a threshold voltage of 0.17V, an off-state leakage current of approx 1nA and a ...

Energy Technology Data Exchange (ETDEWEB)

It has been observed that dislocation loops form and grow during annealing of silicon wafers implanted at doses above the amorphization threshold. Dislocation loops can act to store interstitials for prolonged periods of anneals, sustaining an interstitial super-saturation and thus causing substantial transient enhanced diffusion (TED). The authors have developed a comprehensive model which, in combination with a model and parameters for {l_brace}311{r_brace} defects from previous work, accounts for the formation and evolution of dislocation loops during ion implant annealing, as well as giving the correct TED behavior.

Energy Technology Data Exchange (ETDEWEB)

Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are investigated, developed, and characterized. The tasks comprising these investigations are outlined. A new batch of solar cells was processed using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. Solar cells which were written with laser powers of 5 to 8 watts, gave excellent results with cell efficiencies in the range of 14 to 16%.

Energy Technology Data Exchange (ETDEWEB)

White beam Laue micro-diffraction was performed on directionally solidified, single-crystal Mo pillars in the as-grown state, after focused ion beam (FIB) milling and after pre-straining. The Laue diffraction peaks from the as-grown pillars are very sharp and show no broadening, similar to those from single-crystal Si wafers. Significant broadening and streaking of the peaks occurred after FIB milling and pre-straining, indicative of the damage these treatments induce in the nearly perfect crystal structure of the directionally solidified Mo pillars.

CERN Document Server

A cost effectively method to fabricate nanopores in silicon by only using the conventional wet-etching technique is developed in this research. The main concept of the proposed method is a two-step etching process, including a premier double-sided wet etching and a succeeding track-etching. A special fixture is designed to hold the pre-etched silicon wafer inside it such that the track-etching can be effectively carried out. An electrochemical system is employed to detect and record the ion diffusion current once the pre-etched cavities are etched into a through nanopore. Experimental results indicate that the proposed method can cost effectively fabricate nanopores in silicon.

International Nuclear Information System (INIS)

The influence of electron-beam irradiation on mechanical properties of commercial multilayer flexible packaging materials based on coextruded and laminated polypropylene (PP), low-density polyethylene (LDPE), ethylene vinyl alcohol copolymer (EVOH) and poly(ethylene terephthalate) (PET), irradiated with doses up to 120 kGy, was studied. The tensile strength and elongation at break of the irradiated PET/PP film increase, while the penetration and sealing resistance decreased. In addition, the irradiated PET/LDPE/EVOH/LDPE film presented increase in the tensile strength on some radiation doses and decrease of the penetration and sealing resistance, except for sealing resistance at radiation dose of 15 kGy that resulted in a slight increase of ca 4%.

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.

Energy Technology Data Exchange (ETDEWEB)

Considerable interest has focused recently on the use of lignocellulosic fibers as a reinforcement for thermoplastic polymers. The combination of these dissimilar materials, however, is characterized by a widespread incompatibility that leads to a weak fiber/polymer interface and poor performance properties for the composite. In an effort to improve compatibility a number of fiber surface modification approaches have been investigated including plasma, ozone, and polymer grafting treatments. Evaluation of adhesion improvements has been complicated by processing variables that are difficult to control. This paper will discuss the use of the-micro-debond test in quantifying the interfacial shear strength (ISS) in wood fiber/polystyrene composites. Wood fibers were modified to different degrees with styrene-maleic anhydride copolymers that varied in their composition. The effect of fiber modification on surface energetics was determined using dynamic contact angle ...

British Library Electronic Table of Contents (United Kingdom)

Abstract 1,3 Propanediol (PDO), is now taking the transition from a traditional specialty chemical to a commodity chemical . The market for PDO is growing rapidly as the technology develops. With the advancing PDO production technology, polytrimethylene terephthalate (PTT) as a new type of polyester has been applied in carpet and textile fibers, monofilaments, films, and nonwoven fabrics, and in the engineering thermoplastics area, because PTT has unique properties compared to other polymers such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). Responding to the environmental and sustainability factors, one or two step fermentation technology for PDO production has attracted people's attention. A novel flexible process for PDO production by using aerobic fermentati...

British Library Electronic Table of Contents (United Kingdom)

PurposeThe behavior of trigeminocardiac reflex (TCR) during maxillofacial surgeries has not yet been sufficiently studied and knowledge of its behavior is limited to some case reports. The present study aimed to assess the occurrence of TCR in bilateral sagittal split ramus osteotomy and to determine the possible effect of Gow-Gates block on its incidence. Materials and MethodsTwenty candidates for bilateral sagittal split ramus osteotomy (included were American Society of Anesthesiologists I Class III patients with a prognathism of 3 to 5 mm) were given routine general anesthesia after at least 12 hours of fasting. All patients received Gow-Gates mandibular nerve block on 1 random side (case ramus; the other side was used as the control) after induction of general anesthesia before surger...

Energy Technology Data Exchange (ETDEWEB)

An intake system is described for a direct fuel injection diesel engine having a cylinder block, at least one cylinder in the cylinder block, a piston in the cylinder having a recess on a top surface thereof, a cylinder head mounted on the cylinder block on top of the cylinder, a fuel injector adapted to directly inject fuel into a combustion chamber formed between the lower side of the cylinder head and the recess on the top surface of the piston, and below the injector, and a single exhaust passage opening to the combustion chamber at a location near the injector, the intake system comprising first and second intake passages in the cylinder head, the first and second intake passages are independent of each other and adapted to introduce air into the combustion chamber. The controller means are coupled to the second intake passage for controlling the flow of air therethrough.

International Nuclear Information System (INIS)

This report summarizes the results of a research programme which involves the development of a laboratory experimental facility for the simulation and study of hydro-thermo-mechanical processes in saturated geomaterials with low permeability. The experimentation involves a synthetic cement based porous material made of cement grout which possesses permeabilities in the range of dense unfractured sandstones or shale. Specially manufactured pore-pressure transducers were installed within the cylindrical block at locations adjacent to a plane free boundary. The block was saturated with the periodic application of a vacuum. In its saturated state the plane boundary of the block was subjected to heating via a circular heater the temperature of which was maintained constant. The resulting pore pressure generation along with temperature at these locations was monitored continuously. The results of a series of experiments are ...

British Library Electronic Table of Contents (United Kingdom)

Spatial skills are a central component of intellect and show marked individual differences. There is evidence that variations in the spatial language young children hear, which directs their attention to important aspects of the spatial environment, may be one of the mechanisms that contributes to these differences. To investigate how play affects variations in language, parents and children were assigned to 1 of 3 conditions: free play with blocks, guided play, or play with preassembled structures (Study 1). Parents in the guided play condition produced significantly higher proportions of spatial talk than parents in the other two conditions, and children in the guided play condition produced significantly more spatial talk than those in the free play condition. Study 2 established baseli...

UK PubMed Central (United Kingdom)

Femur fractures typically affect elderly patients with multiple co-morbidities. Pain control can be difficult, requiring intensive nursing and physician care as elderly patients may manifest cardiovascular...Full Text Available

UK PubMed Central (United Kingdom)

The disulfide-reduced form of bovine ribonuclease A (RNAse A), with the Cys thiols irreversibly blocked, was characterized by small-angle x-ray scattering (SAXS). To help resolve the conflicting...Full Text Available

UK PubMed Central (United Kingdom)

Malaria parasites must undergo a round of sexual reproduction in the blood meal of a mosquito vector to be transmitted between hosts. Developing a transmission-blocking intervention to prevent parasites...Full Text Available

UK PubMed Central (United Kingdom)

Dopaminergic (DA) neurons of the mammalian midbrain exhibit unusually low firing frequencies in vitro. Furthermore, injection of depolarizing current induces depolarization block before high...Full Text Available

UK PubMed Central (United Kingdom)

The T-loop motif is an important recurrent RNA structural building block consisting of a U-turn sub-motif and a UA trans Watson–Crick/Hoogsteen base pair. In the presence of...Full Text Available

UK PubMed Central (United Kingdom)

The use of percutaneous transluminal coronary angioplasty is limited by procedural complications and the serious drawback of restenosis, but some new techniques have been developed in an attempt to...Full Text Available

Science.gov (United States)

4-4 Contribution of CM Control Law Terms in. Percent of Total; S Law Top, 9, Law ...... In any given block, some control law terms may be ...

UK PubMed Central (United Kingdom)

Searching for the structural requirements improving the potency and the stereoselectivity of Na⁺ channel blockers as antimyotonic agents, new...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundFourier Transform Infrared Imaging (FTIRI) is used to investigate the amide anisotropies at different surfaces of a three-dimensional cartilage or tendon block. With the...Full Text Available

UK PubMed Central (United Kingdom)

The question of whether proteins originate from random sequences of amino acids is addressed. A statistical analysis is performed in terms of blocked and random walk values formed by binary hydrophobic...Full Text Available

UK PubMed Central (United Kingdom)

Background:During transurethral resection surgery (TUR), accidental stimulation of the obturator nerve can cause violent adductor contraction, leading to serious intraoperative...Full Text Available

UK PubMed Central (United Kingdom)

CF-23“The biggest stumbling block for biological sciences turned out to be synthetic organic chemistry” – Elias A. Zerhouni, Former NIH Director in Chemical...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

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

Science.gov (United States)

Unfamiliar male meadow voles induce pregnancy disruptions when they are in physical contact with females, but the presence of the female's original mate partially protects her from the blocking effects of an unfamiliar male. This research examines how behavioral interactions affect pregnancy disruptions by testing two hypotheses: a) original males protect females by reducing the aggressive interactions between females and strange males; and b) administration of clonidine, an alpha 2-adrenergic receptor agonist that decreases activity, aggression, and sexual motivation, will decrease the pregnancy-blocking ability of strange males. Strange males were more aggressive when the original sire was absent, indicating that this change in behavior may be related to their greater success in disrupting pregnancy. When injected with clonidine, males were less likely to block pregnancy, and they showed less contact and mating behavior ...

UK PubMed Central (United Kingdom)

The incidence of arrhythmias after acute myocardial infarction of the inferior wall varies with the affected segment and increases when there is right ventricular involvement. This paper provides a...Full Text Available

Scientific Electronic Library Online (English)

Abstract in english In this work the air flow in a furnace was computationally investigated. The furnace, for which experimental test data are available, is composed of a movable block burner connected to a cylindrical combustion chamber by a conical quarl. The apertures between the movable and the fixed blocks of the burner determine the ratio of the tangential to the radial air streams supplied to the furnace. Three different positions of the movable blocks were studied at this time. A thr (more) ee-dimensional investigation was performed by means of the finite volume method. The numerical grid was developed by the multiblock technique. The turbulence phenomenon was addressed by the RNG k-epsilon model. Profiles of the axial, tangential and radial velocities in the combustion chamber were outlined. The map of the predicted axial velocity in the combustion chamber was compared with a map of the experimental axial velocity. ...

UK PubMed Central (United Kingdom)

BackgroundInsecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, insecticide resistance poses a serious threat...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

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

Energy Technology Data Exchange (ETDEWEB)

Nanoparticles represent versatile building blocks in material science and nanotechnology. Thereby, the defined assembly of nanostructures (13 and 56 nm in diameter, respectively) is of significant importance. Short DNA sequences can be bound to the nanoparticle surface thus enabling highly specific DNA hybridization-driven events that direct the formation of nanoparticle constructs.In this paper, examples for the defined formation of gold nanoparticle constructs are demonstrated. In addition, gold-silver core-shell nanoparticles are introduced as further building blocks for the hybridization-controlled formation of nanoparticle constructs.

Energy Technology Data Exchange (ETDEWEB)

This report forms part of an independent review of the specifications, execution and results of Task 6 of the Aespoe Task Force on Modelling of Groundwater Flow and Transport of Solutes, which is seeking to provide a bridge between site characterization (SC) and performance assessment (PA) approaches to solute transport in fractured rock. The present report is concerned solely with Task 6C, which relates to the construction and parametrisation of a block-scale hydrostructural model of the TRUE Block Scale region of the Aespoe Hard Rock laboratory. The task objectives, specifications and outcome are summarised and reviewed. Also, consideration is given to how the hydrostructural model might affect the outcomes of Task 6D and 6E. The main conclusions of this review are summarised below: The Task 6C hydrostructural model is a more comprehensive approach to quantitatively describing a volume of fractured rock than has been achieved hitherto. The ...

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 ...

Science.gov (United States)

Continuous wave operation of an Al/sub 0.21/Ga/sub 0.31/In/sub 0.48/P /Ga/sub 0.52/In/sub 0.48/P /Al/sub 0.21/Ga/sub 0.31/In/sub 0.48/P double heterostructure (DH) laser diode was achieved for the first time at 77 K. The device was made from a DH wafer grown by atmospheric metalorganic chemical vapor deposition using triethyl metals and phosphine as source materials. At 77 K, the lasing wavelength was 0.653 ..mu..m and the threshold current was 55 mA for a diode with a nitride-insulated, 8-..mu..m-wide and 250-..mu..m-long stripe geometry.

International Nuclear Information System (INIS)

Radioactive "3"1Si was used as a tracer to study silicon self-diffusion in thin film silicides of cobalt, nickel, palladium and platinum. The specimens were prepared by sequential electron beam evaporation of radioactive "3"1Si and of the metal onto cleaned silicon wafers. By vacuum annealing at the appropriate formation temperature a silicide about 250 nm thick containing a sharp radioactive band about 50 nm thick was generally formed. Subsequent heating above the formation temperature resulted in a spreading of the activity owing to silicon self-diffusion. Activity profiles in the silicides were measured by a combination of ion beam sputtering, radioactivity counting and Rutherford backscattering of charged nuclear particles. (orig.).

Science.gov (United States)

A proposed metallization system for large area silicon solar cells with shallow junctions is outlined, and its desirable features are discussed. A baseline process sequence for the nickel palladium metallization system (NPMS) is delineated. This baseline process sequence is serving as the starting point from which process variations are being performed. The eventual goal is optimization of the NPMS process and determination of the control ranges for NPMS process variables. Initial studies of palladium displacement and electroless chemical plating solutions used in the baseline NPMS have begun and progress is reported. In support of this work, an annotated bibliography (45 citations) dealing primarily with palladium plating and palladium-silicon contact formation has been prepared (and will be subject to updating in the future reports).

International Nuclear Information System (INIS)

Conventional interconnect and switching technology is rapidly becoming a critical issue in the realization of systems using high speed silicon and GaAs based technologies. In recent years clock speeds and on-chip density for VLSI/VHSIC technology has made packaging these high speed chips extremely difficult. A strong case can be made for using optical interconnects for on-chip/on-wafer, chip-to-chip and board-to-board high speed communications. GaAs integrated optoelectronic circuits (IOC's) are being developed in a number of laboratories for performing Input/Output functions at all levels. In this paper integrated optoelectronic materials, electronics and optoelectronic devices are presented. IOC's are examined from the standpoint of what it takes to fabricate the devices and what performance can be expected.

British Library Electronic Table of Contents (United Kingdom)

This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 ? 4 ? 3.5 mm. The frame of the robot is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model was implemented as an HNN system to emulate the lo...

British Library Electronic Table of Contents (United Kingdom)

Abstract Surface modification of topography and chemistry in order to achieve a specific water contact angle (CA) has been explored by using a novel combinatorial screening platform. The screening arrays consisted of 507 distinct combinations of micro-topographies and chemical compositions. By performing chemical modifications with 1H, 1H, 2H, 2H perfluoroethyltriethoxy-silane (PFS) and n-octadecyltriethoxysilane (ODS) on standard silicon wafers it was possible to include both superhydrophobic and very hydrophilic pad arrays in the same screening platform. Surfaces modified with PFS were more hydrophobic than surfaces modified with ODS, while the unmodified silicon surfaces were hydrophilic. For the PFS modified surfaces the largest CAs were achieved with a small pillar size of X-=-1-m and...

Energy Technology Data Exchange (ETDEWEB)

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, {sup 14}C, Kr, Xe, I and {sup 3}H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and {sup 14}C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion ...

International Nuclear Information System (INIS)

Polypeptides, copolymers of #alpha#-amino acids and #alpha#-hydroxy acids, could prove to be a valuable new class of synthetic biodegradable polymers. In this paper. steps in synthesis of poly (dl-lactide-co-3, 6-dimethylmorpholine-2,5-dione) from dl-lactide and dl-3,6-dimethylmorpholine-2,5-dione was explained. dl-Lactide was synthesized from lactic acid. In the reaction of 2-bromopropionyl chloride and dl-alanine, N-(2-bromopropionyl)-dl-alanine was prepared and this material was converted to its salt and finally this salt was converted to 3,6-dimethylmorpholine-2,5-dione in a sublime r. These two monomers, that is d l-lactide and dl-3,6-dimethylmorpholine-2,5-dione was polymerized by ring-opening polymerization. F T-IR, "1H NMR, "1"3C NMR Spectra were used for structure elucidation of all intermediate compounds and final product.

Energy Technology Data Exchange (ETDEWEB)

Products having balanced melting point and decomposition temperature have been developed by employing nylon 6T fundamental molecular structure and selected copolymer components, Arlen being one of the products. It has heat resistance as good as that of super-engineering plastics, low water absorption, and excellent cost-performance which can be used for normal injection molding machines. The unit price per kilogram is low when its high heat resistance is taken into consideration. The coefficient of water absorption is as low as about 1/3 of that of nylon 66, and it can be considered to be a low water absorbing amide. The molding temperature is from 320[degree]C to 350[degree]C, the decomposition temperature is 395[degree]C at 2% weight decreasing temperature, and normal injection molding can be employed. It has excellent soldering resistance, high temperature rigidity, dimensional stability, water absorbing coefficient, as well as good chemical resistance and ...

Energy Technology Data Exchange (ETDEWEB)

Langmuir-Blodgett films have been made with 3-n-hexadecylpyrrole and 3-n-octadecylpyrrole monomers and copolymers with unsubstituted pyrrole made by chemical polymerization at the air-water interface on a subphase containing FeCl/sub 3/. Langmuir-Blodgett films consisting of mixtures of stearic acid and alkylsubstituted polythiophenes have also been made as bilayer films. The orientation of single and multilayer films on platinum substrates have been studied by Near Edge X-ray Absorption Fine Structure Spectroscopy which also gives information about charge transfer interactions between the aromatic groups and the metallic substrates. The alkylsubstituted pyrroles form highly ordered two-dimensional structures. FeCl/sub 3/ initiated copolymerization with unsubstituted pyrrole leads to a more disordered system. In the case of polythiophene-stearic acid bilayers, the stearic acid layers are highly ordered. The poly(alkyl thiophene) layers sandwiched between stearic ...

Energy Technology Data Exchange (ETDEWEB)

The oxidation conditions were investigated for obtaining a higher productivity in the production of high strength carbon fiber from polyacrylonitrile (PAN). The effect of incorporation of 2 % comonomer such as methyl acrylate (MA), acrylate containing carboxylate (SA), acrylamide (AAm), and hydroxyethyl acrylate (HEA) on the oxidation conditions was also investigated. The measurement of DSC and bonded oxygen content revealed that the most effective comonomer for promoting the cyclization of nitril group and the bonding of oxygen was found to be SA, and the second best was AAm. The measurement of tensile strength of carbon fiber showed that the copolymer of SA, HEA, and MA gave a high strength fiber. It took a long time to oxidize the carbon fiber when it was oxidized at a temperature on which double layer structure was not formed. To shorten the production time, a method of combining the upper limit oxidation in which the double layer structure was not formed and ...

Energy Technology Data Exchange (ETDEWEB)

Concerning high performance composite solid propellant BAMO and BAMO-based copolymers, synthetic method and properties of them were studied. Comparison graph of theoretical specific impulse for various propellants were shown, by that, reason why highest specific impulse BAMO was selected as direction of the study. As the orientation of synthesis, those were indicated that radicals at both ends should be hydroxyl so as urethane bonding was available, that liquid at normal temperature was required for easy handling, and that glass transition temperature is required to be low enough. Synthesis was conducted by ring-opening polymerization of ring ether detail procedures of which were explained. Measurements of properties was performed for thermochemical properties, thermal decomposition, combution heat, and friction sensitivity test to confirm safety. As the result, those were understood that thermal decomposition was divided into two phases, rapid exothermal ...

Energy Technology Data Exchange (ETDEWEB)

Silicon on insulator (SOI) structures are promising candidates for the fabrication of VLSI circuits with very high packing densities. The preparation of such structures can now be achieved by high dose implantation of reactive ion species such as oxygen to produce buried layers of SiO/sub 2/ in silicon. In this paper we report experiments to depth profile these layered structures by SIMS. SOI samples have been prepared by implanting (100) silicon wafers with 400 keV molecular oxygen ions at a dose of 1.8x10/sup 18/ O/sup +/ cm/sup -2/. During the implantation the wafers were maintained at temperatures between 325 and 600/sup 0/C, using beam heating, which achieved in situ-annealing and ensured that the top silicon layer remained single crystal. Analysis was carried out on an Atomika DIDA-II spectrometer using 10 keV Ar/sup +/ ions with a low current density of less than 1 mA cm/sup -2/. During analysis negative secondary ions were monitored ...

Energy Technology Data Exchange (ETDEWEB)

The Rebi Block is currently in the early stages of hydrocarbon exploration. The subsurface geology of this area is only known from seismic reflection data. By applying seismic stratigraphy techniques, unconformities and condensed sections were recognized. These discontinuities were dated using paleontological information from the Kulka-1 well, Northwest Shelf of Australia. With these age constraints, seven unconformities and three condensed sections were dated and correlated to the Exxon global sea level curve. The chronostratigraphic charts for the Rebi Block and the Northwest Shelf of Australia have clarified the Mesozoic stratigraphy of the study area. The Exxon global sea level curve has refined the ages determined by conventional paleontological dating. The chart has also helped in predicting source, reservoir and seal potential within a time framework. Prospective stratigraphic traps were those related to the incised valleys at the ...

International Nuclear Information System (INIS)

Objective was to present our 8 year experience in the prevention of the obturator nerve reflex during transurethral resection of bladder tumors. This study was performed in Ataturk University Hospital between 1999 and 2007. We retrospectively reviewed the records of 89 patients with inferolateral bladder tumors, who underwent transurethral resection under epidural or general anesthesia and requested obturator nerve reflex inhibition. Epidural anesthesia was administered to 57 patients, while the remaining 32 patients underwent general anesthesia via mask; and succinylcholine was administered prior to resection. Of the 57 patients received epidural anesthesia, 18 were diagnosed as inferolateral bladder tumors during endoscopy and had to undergo general anesthesia. Obturator nerve block was attempted preoperatively in 39 patients. However, a nerve identification failure, hematoma and 4 obturator nerve reflex events, despite the block, were ...

CERN Document Server

In this paper, we consider the downlink of large-scale multi-cellular OFDMA-based networks and study performance bounds of the system as a function of the number of users $K$, the number of base-stations $B$, and the number of resource-blocks $N$. Here, a resource block is a collection of subcarriers such that all such collections, that are disjoint have associated independently fading channels. We derive novel upper and lower bounds on the sum-utility for a general spatial geometry of base stations, a truncated path loss model, and a variety of fading models (Rayleigh, Nakagami-$m$, Weibull, and LogNormal). We also establish the associated scaling laws and show that, in the special case of fixed number of resource blocks, a grid-based network of base stations, and Rayleigh-fading channels, the sum information capacity of the system scales as $\\Theta(B \\log\\log K/B)$ for extended networks, and as $O(B \\log\\log K)$ and ...

British Library Electronic Table of Contents (United Kingdom)

This prospective study describes and evaluates a surgical approach for 3D reconstruction of the posterior maxilla with autogenous mandibular bone in 16 patients (mean age 51 years). Bone blocks were harvested from the mandible and used as lateral or vertical block grafts (onlay); they were also partially milled and used for sinus elevation (inlay). In 4 cases, anorganic bovine bone was added at the periphery of the blocks. 4 months after grafting, implants were placed in a second operation and loaded after 12 weeks. Lateral and vertical augmentations were measured immediately after grafting and at re-entry for implant placement. Mean lateral augmentation performed was 5.5mm, reduced to 4.3mm (p<0.01) after 4 months' healing. Mean vertical augmentation was 3.2mm, reduced to 2.1mm (p<0.01) a...

Science.gov (United States)

Forty-one patients were treated with epidural neurolysis using 50 % ethyl alcohol 2 ml. Thirty eight patients were suffering from cancer pain and three patients were complaining of chronic benign pain. Alcohol block was repeated 2.3 times (mean) in the same patient. Thirty patients were followed after the treatment. Forty-seven percent of the patients reported 70 % or greater pain relief and 20 % of the patients reported about 50 % pain relief. Duration of pain relief was from 9 days to 203 days with a mean duration of 54 days. Adverse effects were reported 43 % of the patients. There is no miserable adverse effect. Adverse effect reported most was pain with epidural injection of drugs after the alcohol block had been performed. PMID:8544293

International Nuclear Information System (INIS)

Results of three-dimensional laminar and standard K-#epsilon# turbulent numerical simulations of natural convection cooling of ten cubic aluminum blocks mounted on an insulated plate, facing a shrouding wall, are presented. This geometry is chosen so that comparison with experimental results is possible. The considered problem is of great practical importance because it simulates the case of heated electronic chips, mounted on printed board assemblies, which are frequently encountered in electronic industry applications. The problem is mathematically modeled by the three-dimensional conservation differential equations of mass, momentum, energy and turbulent kinetic energy and dissipation (for the turbulent flow model). IN this paper, these equations are numerically solved by a finite volume method and the laminar and turbulent results are compared to the experimental results obtained with similar parameters.

International Nuclear Information System (INIS)

The first 750 MW block of the new South Humber Bank gas-fired combined cycle power plant, sited about 300 km north from London, was officially commissioned in September 12th 1997. The project has been a major success story for Imatran Voima Oy (IVO), which developed the concept and managed the project and owns 22.5 % of the plant; and ABB Power Plants Limited, responsible for the turnkey delivery. IVO Generation Services (UK) is responsible for the running and maintenance of the facility. IVO also manages two other existing plants in Britain, at Brigg (240 MW) and Peterborough (360 MW).

British Library Electronic Table of Contents (United Kingdom)

Differentiation of the vertebrate communities almost coincides with the differentiation of ecosystems in vegetation at the type level, as judged by formalized classifications of various blocks of ecosystems of West Siberia by geobotanical map units, and it differs significantly from that in the underground component due to the greater effect of waterlogging on the latter. In invertebrate communities, significant differences are observed in the boreal-subboreal part, where waterlogging is more significant and greater similarity is found among middle and southern-taiga communities than among subtaiga-steppe ones. Over the groups of map units, the heterogeneity of the vertebrate communities differs from that in all the examined blocks of ecosystems in greater differentiation in the tundra zon...

Energy Technology Data Exchange (ETDEWEB)

A number of epidemiological studies indicate an association between depression and proximity to high voltage transmission lines. These studies have been criticized, however, for using surrogate measures of electromagnetic fields (EMFs) and unstandardized measures of depression. In an effort to overcome these limitations, the Center for Epidemiological Studies Depression (CES-D) scale was administered to 152 women living either adjacent to a transmission line or one block away. Results indicate that homes adjacent to the transmission lines have an average EMF level of 4.86 milligauss at their front door and those one block away have an average of 0.68 milligauss. There was no significant difference in CES-D scores between the groups, controlling for demographic variables. There appeared to be an increase in other health effects, including cancer and miscarriages, but these findings were preliminary and need further investigation.

DEFF Research Database (Denmark)

This article explores how action research, design based research and interaction design can be combined and used in the development of educational robotic tools. Our case study is the development of Number Blocks and it combines physical interaction, learning, and immediate feedback. Number Blocks supports the children's understanding of place value in the sense that it allows them to experiment with creating large numbers. The development was done in collaboration with a class of 7-8 year old children and their mathematics teacher. The article argues that elements from different research methods allowed a structured approach to projects that combines educational research and innovation of new learning technologies. Key elements of this approach is acknowledging the users input, developing a theoretical pre-analysis and using an iterative approach.

Energy Technology Data Exchange (ETDEWEB)

The article surveys studies into the global warming which have found that the OECD countries are responsible for less than half of the total registered warming. Calculation and analysis methods for estimating the global contributions from the blocks of OECD, Africa/America/Middle East, Asia and former Soviet Union/Eastern Europe are presented. The results and some pollution abatement measures are discussed.

International Nuclear Information System (INIS)

The method of treatment of uteral cancer by the brake irradiation of 25 MeV betatrone using original devices which promote forming therapeutic figured bunches is presented. The binding of the protective blocks with a special adjusting frame within the aperture of the diaphragm provided for low relative entering dose which is the advantage of high energy irradiation bunch. The use of the forming devices makes it possible to practice individual treatment and decrease the levels of irradiation doses for intact organs and tissues.

International Nuclear Information System (INIS)

In Daya Bay and Ling'ao Nuclear Power Station, the Microgovernor has the control functions such as synchronization, block loading etc. The control principle of the Microgovernor is right described by sequence diagram for the first time. That the fault occurred in the synchronization process of Daya Bay Nuclear Power Station unit 1 is also analyzed and illustrated. (author)

Energy Technology Data Exchange (ETDEWEB)

In combined cycle turbine power stations, soft material compensators are used which, if the full pressure fails, also withstand a small external pressure. Innovative forms of construction which guarantee useful life, are presented in relation to the design. Damaging effects, which limit the life of these special soft material compensators, are discussed. (orig.)

UK PubMed Central (United Kingdom)

σ-Receptor (σR) antagonists have been reported to block certain effects of psychostimulant drugs. The present study examined the effects of σR ligands in rats trained to self-administer...Full Text Available

CERN Document Server

We define the Bloch spectrum of a quantum graph to be the collection of the spectra of a family of Schr\\"odinger operators parametrized by the cohomology of the quantum graph. We show that the Bloch spectrum determines the Albanese torus, the block structure and the planarity of the graph. It determines a geometric dual of a planar graph. This enables us to show that the Bloch spectrum completely determines planar 3-connected quantum graphs.

Wastenet

... Further complications resulted from the requirement to use existing piled foundations and columns which had originally been designed to accommodate a six-storey office block. The hotel bedroom configurations and planning constraints were different from thos Related Services Structural Design Go View all Services Find Projects Sector All Sectors Buildings & Infrastructure Environment Natural Resources Transportation Sub Sector All Sub-Sectors Country All Countries Angola Antigua and Barbuda Argentina Australia Azerbaijan ...

UK PubMed Central (United Kingdom)

In monocytes, sulfatide, a lipid from Mycobacterium tuberculosis, blocked priming for enhanced release of superoxide (O2-) by the macrophage activating factors lipopolysaccharide, gamma interferon,...Full Text Available

UK PubMed Central (United Kingdom)

The NSABP B-32 trial is examining whether patients with initially negative sentinel lymph nodes (SLNs) who have occult metastases detected on deeper levels and cytokeratin immunohistochemistry...Full Text Available

Science.gov (United States)

A cryostat is described that was developed for irradiating a number of small metal specimens with a high beamcurrent of heavy particles at liquid nitrogen temperature. The specimens, which are mounted on a block, are taken out of the cryostat after irradiation and subsequently annealed in a temperature bath. The progress of annealing is followed by measuring the change in electrical resistivity of the specimens in liquid helium. (auth)

Energy Technology Data Exchange (ETDEWEB)

A nozzle plug for blocking a nozzle in a nuclear steam generator is improved by the addition of hinges which allow the nozzle plug to be inserted into the steam generator through an access port of substantially smaller diameter than the nozzle. A recess is provided in one of the semi-circular plates allowing the plates to nest, further reducing the necessary size of the access port.

UK PubMed Central (United Kingdom)

Using an anti-receptor mAb that blocks the attachment of echovirus 7 and related viruses (echoviruses 13, 21, 29 and 33), we have isolated a complementary DNA clone that encodes the human decay-accelerating...Full Text Available

International Nuclear Information System (INIS)

Computerized tomography-guided neurolytic splanchnic nerve block is a technique for relieving abdominal cancer pain; the goal is the alcoholic neurolytic interruption of the sensitive structures in retroperitoneal space. Computerized tomography yields accurate anatomical detailing and the course for needle placement and alcohol spread. January, 1993, to July, 1996, twenty-one bilateral splanchnic nerve blocks were performed through the posterior access. Forty-eight hours after alcoholism. 14 patients (66%) had complete pain regression; 52% of the patients needed no analgesics for 6 to 54 days and only 9 patients (42%) needed another low opioid therapy. Complications included hypotension and diarrhea in all cases. One had a cardiac arrest and diet 8 days after the procedure. There were no other complications. The whole procedure usually lasted 60 min (range: 45 to 90 min). Splanchnic nerve neurolysis is a useful treatment in the patients with ...

CERN Document Server

To reduce the number of regular break-ins on CERN machines due to passwords exposed on the network in clear text, OFF-SITE FTP ACCESS TO CERN WILL BE BLOCKED in the CERN firewall from: Tuesday 20th January 2004 If you use ftp to access CERN computers from outside CERN then please see the link below for alternative access means and further advice: http://cern.ch/security/ftp Denise Heagerty, CERN Computer Security officer, Computer.Security@cern.ch

Energy Technology Data Exchange (ETDEWEB)

Pairing correlations in multi-quasiparticle states in deformed nuclei are expected to be reduced because of blocking. New intrinsic states and their associated rotational bands have been identified allowing comparisons to be made as a function of seniority and between nuclei. The possible effects of the reduced pairing on the collective rotation, and its manifestation in terms of alignment, are discussed. 13 refs., 2 figs.

Energy Technology Data Exchange (ETDEWEB)

Yellow-emitting pulsed laser operation of an Al/sub 0.37/Ga/sub 0.15/In/sub 0.48/P/Al/sub 0.16/Ga/sub 0.36/In/sub 0.48/P/ Al/sub 0.37/Ga/sub 0.15/In/sub 0.48/P double heterostructure laser diode was obtained at 77 K. The emission wavelength was 579 nm. The threshold current density was 5.6 kA/cm/sup 2/ for a diode with a Si/sub 3/N/sub 4/ insulated 8-..mu..m-wide and 250-..mu..m-long stripe geometry. The device was made from a DH wafer grown by conventional metalorganic chemical vapor deposition using triethyl metals and phosphine as source materials.

CERN Document Server

Surface compositional changes in GaAs due to RF plasmas of different gases have been investigated by XPS and etch rates were measured using AFM. Angular Resolved XPS (ARXPS) was also employed for depth analysis of the composition of the surface layers. An important role in this study was determination of oxide thickness using XPS data. The study of surface - plasma interaction was undertaken by correlating results of surface analysis with plasma diagnosis. Different experiments were designed to accurately measure the BEs associated with the Ga 3d, Ga 2p sub 3 sub / sub 2 and LMM peaks using XPS analysis and propose identification in terms of the oxides of GaAs. Along with GaAs wafers, some reference compounds such as metallic Ga and Ga sub 2 O sub 3 powder were used. A separate study aiming the identification of the GaAs surface oxides formed on the GaAs surface during and after plasma processing was undertaken. Surface compositional changes after plasma treatment, ...

Energy Technology Data Exchange (ETDEWEB)

Room-temperature cw operation for InGaP/InGaAlP double heterostructure (DH) laser diodes on GaAs substrates was achieved for the first time. The DH wafers were grown by low-pressure metalorganic chemical vapor deposition using methyl metalorganics. A lasing wavelength of 679 nm and a threshold current of 109 mA at 24C were obtained for an inner stripe structure laser diode with a 250- m-long and 7- m stripe geometry. The laser operated at up to 51C. The characteristic temperature T0 was 87 K at around room temperature. The lowest threshold current density, 5.0 kA/cmS, was obtained with a 20- m stripe width laser diode under room-temperature pulsed operation.

International Nuclear Information System (INIS)

The differential recoil cross sections of H have been determined for 1.5-3.0 MeV He"+ incidence. In order to obtain precise data, we have performed simultaneous detection and spectrum simulation of recoiled H and backscattered He. In addition, a careful cross check has been made by secondary ion mass spectrometry (SIMS). The present results have revealed a pronounced contribution from a nuclear short-range interaction. The He"+ energy and recoil angle dependence of the H recoil cross sections are well reproduced by adding the nuclear term, which is simply derived from effective range theory. Our computer simulation program of elastic recoil combined with Rutherford backscattering spectra makes it possible to determine the depth distributions of H together with other elements absolutely, without any ambiguities. The present elastic recoil analysis is employed to determine the H composition of amorphous Si(H) films deposited on Si wafers. An excellent agreement, ...

Energy Technology Data Exchange (ETDEWEB)

A route, as followed by ECN, is described for development of SiN{sub x}:H layers deposited by microwave (MW) PECVD, which are suited for surface and bulk passivation of mc-Si solar cells. First research was focussed on surface passivation and this resulted in the development of SiN layers that were Si-rich and where the hydrogen is mainly bonded to silicon atoms. A disadvantage of such Si-rich layers is their large absorption at shorter wavelengths, which make them unsuitable as front side AR coatings. Further, these layers appeared to be less suitable for bulk passivation. The next step therefore was the development of SiN layers for bulk passivation. For good bulk passivation of solar cells by means of a thermal anneal of the SiN layers, we found that SiN layers with high N-H bonding concentrations are required. Fine-tuning of the deposition conditions of these layers, finally resulted in the development of a SiN layer type which combines the three desired properties: low absorption ...

Science.gov (United States)

A metallization scheme has been developed which allows selective plating of silicon solar cell surfaces. The system is comprised of three layers. Palladium, through the formation of palladium silicide at 300/sup 0/C in nitrogen, makes ohmic contact to the silicon surface. Nickel, plated on top of the palladium silicide layer, forms a solderable interface. Lead-tin solder on the nickel provides conductivity and allows a convenient means for interconnection of cells. To apply this metallization, three chemical plating baths are employed. Palladium is deposited with an immersion palladium solution and an electroless palladium solution, and nickel is deposited with an electroless nickel solution. Solder is applied with a molten solder dip. Extensive development work has been performed to achieve an effective immersion palladium solution formulation, leading to reproducible formation of the palladium silicide contact layer. This metallization system has been repeatedly demonstrated to be ...

International Nuclear Information System (INIS)

An attempt was made to minimize the channeling tail by implantation along a random equivalent direction following a careful alignment of the target. In order to analytically determine the random equivalent directions, critical angles for channeling were mapped on a stereogram. Boron ions with energies of 17 and 45 keV are implanted along specified directions determined from the map. The depth distribution of the dopant is profiled by SIMS and the effects of water orientation upon the channeling tail are noted. Industrial common use of a 7"0 tilt is not optimum. However, implantation with the wafer tilted at 5.5 +/- 0.5"0 from the surface normal and rotated at 7.0 +/- 0.5"0 from a (100) plane shows the least channel-tail compared to implantation along other directions. Rapid thermal annealing (RTA) is a promising annealing method for shallow junction formation. Transient enhanced diffusion of implanted boron is observed. Two different mechanisms for the boron ...

Energy Technology Data Exchange (ETDEWEB)

Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. A literature search was carried out on the various state-of-the-art laser-assisted techniques for metal deposition, including laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. The results of the literature survey are briefly summarized. Experiments were carried out on laser-enhanced electroplating. Deposition of metals by laser-assisted pyrolysis of a variety of metallo-organic inks and metal-bearing polymer solutions spun as films onto silicon wafers was carried out. A detailed study of the various models of localized surface temperature rise in silicon due to laser heating has been carried out. Progress is reported in fabricating laser-metallized solar cells with improved efficiencies. Cells fabricated are characterized. A preliminary economic ...

Energy Technology Data Exchange (ETDEWEB)

Al{sub x}Ga{sub 1{minus}x}P layers (0 {le} x {le} 0.7), with thicknesses of {ge}1 {micro}m were grown on Si (100) wafers by metal-organic molecular beam epitaxy (MOMBE) at 450 C. Transmission electron micrographs of the single crystal films revealed that the microstructure contains stacking faults and microtwins especially near the interface as well as both threading and misfit dislocations. Hardness and elastic modulus were measured using a Nanotest 500 indenter, which can probe the film properties without influence from the substrate. The hardness H varies linearly according to (11.8 {minus} 2.3x) GPa. The absence of alloy hardening is due to the fact that there is no difference in atomic size of Al and Ga. The indentation modulus E/(1{minus}v{sup 2}) decreases monotonically from 136 GPa for GaP to 129 GPa for Al{sub 0.7}Ga{sub 0.3}P and bows only slightly (about 2%) below the straight line of linear interpolation.

Energy Technology Data Exchange (ETDEWEB)

In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics demonstrated that ...

Energy Technology Data Exchange (ETDEWEB)

(001) CZ silicon wafers were implanted with arsenic (As{sup +}) at energies of 10--50 keV to doses of 2 {times} 10{sup 14} to 5 {times} 10{sup 15}/cm{sup 2}. All implants were amorphizing in nature. The samples were annealed at 700 C for 16 hrs. The resultant defect microstructures were analyzed by XTEM and PTEM and the As profiles were analyzed by SIMS. The As profiles showed significantly enhanced diffusion in all of the annealed specimens. The diffusion enhancement was both energy and dose dependent. The lowest dose implant/annealed samples did not show As clustering which translated to a lack of defects at the projected range. At higher doses, however, projected range defects were clearly observed, presumably due to interstitials generated during As clustering. The extent of enhancement in diffusion and its relation to the defect microstructure is explained by a combination of factors including surface recombination of point defects, As precipitation, As ...

British Library Electronic Table of Contents (United Kingdom)

Si nanocrystal floating gate MOS capacitors were formed on p-Si (100) wafers by thermal plasma jet (TPJ) annealing of SiO2/SiOx /SiO2/Si(100) stacked structure. The chemical composition of SiOx layer was controlled by changing the SiH4, He, and O2 gas flow ratio during plasma enhanced chemical vapour deposition. The MOS capacitors showed clear hysteresis in capacitance-voltage (CV) characteristics after TPJ annealing. The hysteresis width shows maximum value when initial composition x =1.7, which shows the maximum photoluminescence (PL) intensity. The maximum hysteresis width of 6.8 V was observed with gate voltage swept between 20 and -20 V in x = 1.7 sample. The result means 7.4 x 1012 cm-2 carriers are injected to or emitted from Si nanocrystals. The duration of 1 V shift in flatband vo...

International Nuclear Information System (INIS)

In this experiment, a Si wafer containing four lightly doped B marker layers epitaxially grown by CVD has been implanted with 100 keV Si"+ ions to a dose of 2 x 10"1"4 ions/cm"2 and annealed at 850 deg. C for several times in an RTA system in flowing N_2. TEM and SIMS analysis, in conjunction with a transient enhanced diffusion (TED) evaluation method based on the kick-out diffusion mechanism, have allowed us to accurately study the boron TED evolution in presence of extended defects. We show that the silicon surface plays a key role in the recombination of Si interstitial atoms by providing the first experimental evidence of the resulting Si_i_n_ts supersaturation gradient between the defect region and the surface. Our results indicate an upper limit of about 200 nm for the surface recombination length of Si interstitials at 850 deg. C in a N_2 ambient.

International Nuclear Information System (INIS)

A mass separated focused ion beam (FIB) is a very useful tool to fabricate nanostructures by writing implantation within an ion beam synthesis process. In these investigations the IMSA-OrsayPhysics FIB, equipped with a Co_3_6Nd_6_4 alloy liquid metal ion source, was applied. Si(100) and (111) wafers were implanted with 60 keV Co"+"+ ions in the dose range of 2 . 10"1"6 to 2 . 10"1"7 cm"-"2. Implantation parameters were investigated, like pixel dwell time, relaxation time (time between two cycles), dose rate as well as the pixel overlapping factor. The subsequent annealing was done in a two step process, namely 600 deg. C for 60 min and 1000 deg. C for 30 min in a N_2 ambient. The results obtained by SEM investigations in terms of continuous nanowire structures following the direction and interrupted CoSi_2 pattern in the direction show a clear dependence on the time scale as well as the scanning mode of the irradiation. Structure sizes as small as 10 nm are ...

Energy Technology Data Exchange (ETDEWEB)

Traditionally wafer bumps are made from Pb containing solders. Over 20 years ago IBM recognized that {sup 210}Pb has a decay chain resulting in a 5.4 MeV alpha particle that induces soft errors. A variety of efforts to produce and characterize low alpha Pb ensued. Work at Honeywell over the past several years has shown that low alpha lead activity does not follow the decay signature predicted from {sup 210}Pb secular equilibrium. Data are presented indicating that smelting has a minimal effect on {sup 210}Pb/{sup 210}Po secular equilibrium and that other trace radionuclides are the alpha source. The implications of these data to possible alpha emitter sources in lead free solders are discussed, along with a method developed by Honeywell to remove alpha emitters from lead free solder components.

International Nuclear Information System (INIS)

K"#pi#=20"- and 49/2"- yrast isomers have been discovered in "1"7"6Ta and "1"7"7Ta, with meanlives of 1.4 ms and 0.19 ms, respectively. The long meanlives arise from substantial K-hindrance in the "1"7"6Ta case but from spin-trapping in the "1"7"7Ta case. Quasiparticle calculations, which treat the Fermi and pairing energies self-consistently, reproduce the excitation energies of these isomers and the other multi-quasiparticle high-K states observed. Due to blocking, pairing is significantly reduced in the 3-quasiparticle states, the extent depending on the specific configurations. It is completely quenched for both protons and neutrons in the highest seniority states. Yrast traps of even higher spin are predicted to exist in "1"7"6Ta and "1"7"7Ta. ((orig.)).

CERN Document Server

Extensive investigations have been and are being carried out on a stiff clay from an underground research laboratory located at Mol (Belgium) called Boom clay, in the context of research into deep nuclear waste disposal. Suction effects in deep Boom clay block samples were investigated through the characterisation of the water retention and of the swelling properties of the clay. The data obtained allowed an estimation of the sample initial suction that was reasonably compatible with the in-situ state of stress at a depth of 223 m. The relationship between suction and stress changes during loading and unloading sequences were also examined by running oedometer tests with suction measurements. A rather wide range of the ratio s/sigma 'v (being s the suction and sigma 'v the effective vertical stress) was obtained (0.61 - 1), different from that proposed by Bishop et al; (1974). Finally, the effect of suction release under an isotropic stress close to the estimated ...

Energy Technology Data Exchange (ETDEWEB)

Nuclei in the mass-180 region have many high-{Omega} single-particle levels close to the Fermi energy and are, therefore, prime candidates for high-K isomers. Since both neutron and proton level densities are rather low, one should expect blocking and particle-number fluctuations to be rather important. We have performed good-particle-number calculations and have shown that the simpler blocked BCS theory gives a good approximation to the multi-quasiparticle spectra if the pairing strength is chosen appropriately. This has allowed us to perform a systematic theoretical study of this mass region. Residual spin-spin interactions are shown to be essential in reproducing the energies and even the correct order of known states. Good agreement has been found for {sup 175}Hf, {sup 176}Hf and {sup 177}Ta, where extensive data already exist. Predictions for new high-K states near the yrast line are made for these nuclei and for {sup 178}W. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A total of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of ...

International Nuclear Information System (INIS)

A wear-resistant nitrided layer was formed on a 304L austenitic stainless steel substrate by DC plasma nitriding. Effects of DC plasma nitriding parameters on the structural phases, micro-hardness and dry-sliding wear behavior of the nitrided layer were investigated by optical microscopy, X-ray diffraction, scanning electron microscopy, micro-hardness testing and ring-on-block wear testing. The results show that the highest surface hardness over a case depth of about 10 #mu#m is obtained after nitriding at 460 deg. C. XRD indicated a single expanded austenite phase and a single CrN nitride phase were formed at 350 deg. C and 480 deg. C, respectively. In addition, the S-phase layers formed on the samples provided the best dry-sliding wear resistance under the ring-on-block contact configuration test.

Energy Technology Data Exchange (ETDEWEB)

What kind of hardware and software should be used to interface GPIB devices with the existing computer system. One idea was to use a commercially available Multibus card, BLC 8488 from National Semiconductor, whose on-board Z80 would manage the GPIB read/write functions and handshakes. With this card, one could make a hardware system which would consist of (1) CAMAC 080, (2) Multibus crate, (3) M. Shea's M68000, (4) M080, (5) BLC 8488 and (6) memory board. And the software considered for such a hardware package was GAS, which had been an established software package for communication between the ACNET computer system and smart CAMAC modules. However, a second idea was to put everything on a two-wide CAMAC module. The author pursued the second idea and came up with a two-wide CAMAC module called C488. The author describes the hardware - block diagrams, circuit blocks, front panel and hardware tests. He also refers to the software - ...

Energy Technology Data Exchange (ETDEWEB)

The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

Energy Technology Data Exchange (ETDEWEB)

Laser surface alloying with gaseous nitrogen was utilized to improve the wear resistance of a Ti-6Al-4V alloy. Wear-resistant composite coatings reinforced by hard TiN dendrites were produced 'in-situ' on a substrate of a Ti-6Al-4V alloy. The hardness and wear resistance of the laser alloyed coating under two-body abrasive and block-on-ring full-sliding wear conditions were significantly enhanced. (orig.)

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.

Science.gov (United States)

A previous paper introduced the use of wave digital filters as a basic building block for power system simulation, particularly suitable for real-time applications. This paper stresses the simulation of non-linear and switching elements, emphasizing the advantages of the wave filters implementation. The digital structure is maintained even when non-linear components change their characteristics or power electronic devices switch their states. As a very important by-product, the suppression of numerical oscillations related to the trapezoidal rule is achieved in a rather simple way, with no effects on simulation results.

Energy Technology Data Exchange (ETDEWEB)

In the power station West Block 2 at Voerde (Federal Republic of Germany), cracks in the final stage of the shaft were determined at the ND1 rotor of the 350 MW condensation tube was determined. A purely mechanical preparation of the crack was not possible due to the depth of the crack. A substitute rotor was not available. A repair solution was developed covering a welding of a new shaft section to the existing rotor. The authors of the contribution under consideration report on the damage, cause of the damage, repair solution and the process of repair.

Energy Technology Data Exchange (ETDEWEB)

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

Science.gov (United States)

The present paper further characterizes the cholinergic properties of acetylselenonium choline (ASeCh, (CH3)2Se+CH2CH2OCOCH3). The data demonstrate that ASeCh possesses muscarinic receptor agonist properties as evidenced by vasodepressor and smooth muscle contractile activities which are enhanced by physostigmine and antagonized by atropine. ASeCh also possessed nicotinic agonist activity on frog rectus abdominis tissue which was potentiated by physostigmine, and blocked by d-tubocurarine. The relative potencies of ASeCh ranged from approximately 1% to approximately 6% of the potency of acetylcholine in the three types of preparations examined. PMID:1435078

British Library Electronic Table of Contents (United Kingdom)

Abstract Neurodegenerative and neurometabolic disorders may cause significant morbidity and mortality in children. Imaging is important in early diagnosis of metabolic disorders and in determining the extent of brain injury. Especially after the development of new techniques such as diffusion-weighted magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), neuroimaging plays more important role in the diagnosis and management of these disorders. In these disorders, usually a mutation causes a clinically significant block in one or more metabolic pathways. This blockage usually results in either a deficiency of the product or in an accumulation of substrate with damage induced by either storage or toxicity. The presenting symptoms are usually nonspecific. In some of the ...

Science.gov (United States)

Lumbar epidural anesthesia is useful in a variety of chronic benign pain syndromes, including lumbar radiculopathy, low back pain syndrome, spinal stenosis, and vertebral compression fractures. Given the increased number of epidural nerve blocks being performed, some have reported unexplained complications of a transient or permanent nature and with varying degrees of severity. However, no case has been reported of a broken epidural needle tip retained in the lumbar facet joint area. This represents the first reported case presentation of foraminal stenosis developing in a patient after a retained epidural needle tip. PMID:21286465

Energy Technology Data Exchange (ETDEWEB)

Epoxy-resin based neutron shielding material, NS-4-FR, is used for spent fuel transport and/or storage cask. In this paper the outline of thermal aging test performed to evaluate the heating effect on this neutron shielding material, NS-4-FR, is introduced. The test is consisted of two kinds of thermal aging test, one is 'Basic Test' and the other is 'Block Heating Test'. The former is cooperatively performed by ten Japanese Electrical Power Companies, and the latter is done by GESC and NOF Corporation. (authors)

International Nuclear Information System (INIS)

Two new identical insertion devices have been designed for the Daresbury SRS. They are 2T permanent-magnet multipole wigglers that will provide high flux in the X-ray region. This paper describes the magnetic and mechanical design of the arrays of steel pole pieces and permanent-magnet blocks. Also given is the engineering design of the support structure that will cope with the very large forces present while maintaining high levels of precision in gap setting and parallelism. The engineering design has been fully assessed using finite-element techniques to predict the deflections of critical parts of the structure. These two devices are due to be installed into the SRS by the end of 1998.

Science.gov (United States)

This construction curriculum guide on masonry for secondary students is one of six developed for inservice teachers at Marianas High School in Saipan. The guide provides the rationale, description, goals, and objectives of the program; the program of studies and performance objectives by levels; samples of lesson plans for effective delivery of instruction; and a listing of references. Concepts covered include orientation to masonry construction, safety, tools and equipment, cement, concrete, concrete block masonry, concrete forms, and concrete reinforcement. Appended materials include transparency copies, tests and answer keys, information sheets, and student activities. (CT)

International Nuclear Information System (INIS)

Aim: To evaluate the role of computed tomography (CT) in needle placement for ganglion impar blocks, and to determine the efficacy of CT-guided ganglion impar blocks in the management of coccydynia. Materials and methods: The results of ganglion impar blockade in eight patients with coccydynia secondary to trauma or unknown cause were reviewed. The diagnosis of coccydynia was based on clinical history, location of pain, and response to previous diagnostic and therapeutic procedures. The eight patients were treated with CT-guided ganglion impar blocks to manage their coccyx pain after conservative procedures, including oral medication and cushions, failed to provide relief. All patients were subjected to ganglion impar blocks under a thin-section CT-guided technique for needle placement, using a mixture of bupivacaine and triamcinolone. The patients were followed-up for a period of 6-months. Results: ...

Energy Technology Data Exchange (ETDEWEB)

A process has been developed that exploits the characteristics of microwave heating for the vitrification of high-level radioactive liquid waste. This process, microwave vitrification, has been successfully operated at pilot plant scale in an active cell using simulated liquid waste containing several curies of radioactivity. Excellent decontamination factors have been achieved for both volatiles and nonvolatiles with an average ruthenium decontamination factor of 490 and a gross alpha emitter decontamination factor of 100,000. Almost all the radioactivity is incorporated in a glass block.

Energy Technology Data Exchange (ETDEWEB)

The available experimental data on the (/sup 3/He,n) reaction between the ground states of even-even nuclei and lowest 1/2/sup -/ levels of odd-A nuclei in the Aapprox.=100 region are analyzed in a systematic way by the DWBA. The deduced relative intensities of these two-proton transfers, and their uncertainties, are compared to the predictions of various nuclear models. In particular, the influence of the finite dimension of the configuration space available to the transferred protons, and of the blocking effect of a 2p1/2/sup -/ proton, are examined. (orig.).

International Nuclear Information System (INIS)

In this study, a high-resolution characteristic-based finite-volume (FV) method on unstructured grids [Int. J. Numer. Method Eng. 50 (2001) 11; Int. J. Heat Fluid Flow 21 (2000) 432] is extended by a matrix-free implicit dual-time stepping scheme for the numerical simulation of steady and unsteady flow and heat transfer with porous media. The method has been used to study the characteristics of a complex problem: flow and heat transfer in a channel with multiple discrete porous blocks, which was originally proposed by Huang and Vafai [J. Thermophys. Heat Transfer 8 (3) (1994) 563]. In addition, flow and heat transfer in a channel partially or fully filled with porous layers and containing solid protruding blocks with constant heat flux on its lower surface are also investigated in details. Hydrodynamic and heat transfer results are reported for both steady and transient flow cases. In particular, the effects of Darcy and Reynolds numbers on ...

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 wall mock-up, a two-step brazing was tried. All mock-ups and ...

Energy Technology Data Exchange (ETDEWEB)

This SBIR Phase I developed neutron detectors made from gallium arsenide (GaAs) p-type/ intrinsic/n-type (P-I-N) diodes grown by metalorganic chemical vapor deposition (MOCVD) onto semi-insulating (S1) bulk GaAs wafers. A layer of isotonically enriched boron-10 evaporated onto the front surface serves to convert incoming neutrons into lithium ions and a 1.47 MeV alpha particle which creates electron-hole pairs that are detected by the GaAs diode. Various thicknesses of ''intrinsic'' (I) undoped GaAs were tested, as was use of a back-surface field (BSF) formed from a layer of Al{sub x}Ga{sub 1-x}As. Schottky-barrier diodes formed from the same structures without the p+ GaAs top layer were tested as a comparison. After mesa etching and application of contacts, devices were tested in visible light before application of the boron coating. Internal quantum efficiency (IQE) of the best diode near the GaAs bandedge is over 90%. The ...

Science.gov (United States)

This study investigated the feasibility of using a new adsorbent prepared from coconut coir pith, CP (a coir industry-based lignocellulosic residue), for the removal of uranium [U(VI)] from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto CP using potassium peroxydisulphate-sodium thiosulphite as a redox initiator and in the presence of N,N'-methylenebisacrylamide as a crosslinking agent. IR spectroscopy results confirm the graft copolymer formation and carboxylate functionalization. XRD studies confirm the decrease of crystallinity in PGCP-COOH compared to CP, and it favors the protrusion of the functional group into the aqueous medium. The thermal stability of the samples was studied using thermogravimetry (TG). Surface charge density of the samples as a function of pH was determined using potentiometric titration. The ability of PGCP-COOH to remove ...

International Nuclear Information System (INIS)

Transient enhanced diffusion (TED) from implantation of 5keVB_1_0H_1_4 and 0.5 keV B ions has been quantified and compared for nominal boron doses of 10"1"4 and 10"1"5cm"-"2. Boron diffusivity during annealing was extracted from secondary ion mass spectroscopy depth profiles of diffused marker layers in boron doping-superlattices and the actual implanted B dose was independently measured by nuclear reaction analysis. Comparable enhancements were observed from both ions. Transmission electron microscopy analysis revealed that both boron- and decaborane-implanted samples were amorphized at a nominal 10"1"5cm"-"2B dose. A comparison with data from low energy Si implants revealed a similar dependence of diffusivity enhancement on implant dose. These findings are consistent with the understanding that TED is caused by the interstitial supersaturation resulting from a number of excess interstitials approximately equal to the number of implanted atoms which can become substitutional in the ...

Energy Technology Data Exchange (ETDEWEB)

ZnO thin films were electrodeposited in aqueous solution on gilded p-type Si wafer substrates. Thermal treatments were carried out on different films in Ar atmosphere at different temperatures, between 200 and 600 {sup 0}C. Surface morphology studies using scanning electron microscopy and atomic force microscopy show a smooth surface for an annealing temperature of 400 {sup 0}C with a roughness mean square value of about 15 nm and a precipitation of ZnO microcrystals on the deposit surface at 600 {sup 0}C. X-ray diffraction experiments reveal a decrease in the c-parameter value from 5.223 to 5.206 A after treatment at 600 {sup 0}C, due to the removal of hydrogen from the film. Raman spectroscopy analyses show an improvement in the crystal quality of the film and a decrease in the compressive stress inside the deposit. Photoluminescence observations reveal an important change in the UV emission band after annealing at 200 {sup 0}C. A visible region emission band at ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of the Spatial Signature Analysis (SSA) Electrical-test (e-test) validation study that was conducted between February and June, 1998. SSA is an automated procedure developed by researchers at the Oak Ridge National Laboratory to address the issue of intelligent data reduction while providing feedback on current manufacturing processes. SSA was initially developed to automate the analysis of optical defect data. Optical defects can form groups, or clusters, which may have a distinct shape. These patterns can reveal information about the manufacturing process. Optical defect SSA uses image processing algorithms and a classifier system to interpret and identify these patterns, or signatures. SSA has been extended to analyze and interpret electrical test data. The algorithms used for optical defect SSA have been adapted and applied to e-test binmaps. An image of the binmap is created, and features such as geometric and invariant moments are extracted and ...

International Nuclear Information System (INIS)

A set of advanced models implemented into the simulator Sentaurus Process was applied to simulate ultra shallow junction formation by flash lamp annealing (FLA). The full path transient enhanced diffusion model includes equations for small interstitial clusters (I_2, I_3, I_4), #left brace#3 1 1#right brace# defects and dislocation loops. A dopant-point defect clustering model is used for dopant activation simulation. Several cluster types are considered: B_2, B_2I, B_2I_2, B_3I, B_3I_2, B_3I_3 for boron and As_2, As_2V, As_3, As_3V, As_4, As_4V for arsenic. Different point defect and dopant-point defect pair charge states are taken into account to obtain accurate results in the high doping level region. The flux expressions in the three-phase segregation model include a dependence on the doping level and point defect supersaturation. The FLA process was performed at various peak temperatures in a Mattson Millios"T"M fRTP"T"M system. The measured wafer temperature ...

Energy Technology Data Exchange (ETDEWEB)

The laser grooved buried grid (LGBG) cell was developed at the University of New South Wales, Australia. The enormous advantage of the Saturn technology is the simple formation of a selective emitter via two step diffusion, which is optimised on the surface for the charge carrier generation and under the metal grid for contact formation. The reflection losses due to shading are simultaneously minimised by the installation of the contacts at right angles in the wafer surface. Due to the increased infeed compensation, particularly the compensation covering the costs, the economic importance of the energy yield of a PV plant is growing. Ultimately, it is not just the installed output (KWp) that matters to the customer, but increasingly the specific yield (kWh/kWp). An increased energy yield with optimally matched components with the Saturn technology means high annual compensation, which in turn shortens the amortisation period. [Deutsch] Die LGBG-Zelle wurde an der ...

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Significant ion irradiation during film growth is required for the formation of cubic boron nitride (cBN) films. Meanwhile, a huge level of intrinsic stress possibly induced by the ion bombardment has been frequently reported to result in cracking and/or lack of adhesion of deposited cBN films. The present work has been performed to investigate the interfacial and/or the buffer layer structures with better matching to the cBN film by relaxation of the film stress using ion-beam-assisted deposition (IBAD). Boron nitride films have been synthesized on Si(100) wafer and tungsten carbide (WC) substrates by depositing boron vapor under simultaneous bombardment with nitrogen ions and nitrogen-argon mixture ions in the energy range of 0.5-10 keV. Cubic BN films with enhanced tribological properties have been explored by inserting a BN layer with various B/N compositions as a controlled buffer at the interface. Significant relaxation of the film stress has been observed ...

Energy Technology Data Exchange (ETDEWEB)

Commercial focused ion beam (FIB) systems are commonly used to image integrated circuits (ICS) after device processing, especially in failure analysis applications. FIB systems are also often employed to repair faults in metal lines for otherwise functioning ICS, and are being evaluated for applications in film deposition and nanofabrication. A problem that is often seen in FIB imaging and repair is that ICS can be damaged during the exposure process. This can result in degraded response or out-right circuit failure. Because FIB processes typically require the surface of an IC to be exposed to an intense beam of 30--50 keV Ga{sup +} ions, both charging and secondary radiation damage are potential concerns. In previous studies, both types of effects have been suggested as possible causes of device degradation, depending on the type of device examined and/or the bias conditions. Understanding the causes of this damage is important for ICS that are imaged or repaired by a FIB between ...

International Nuclear Information System (INIS)

A wide variety of thin film coatings, deposited by different techniques and with potential applications in various important areas, have been characterised by the Phase Modulated Spectroscopic Ellipsometer, installed recently in the Spectroscopy Division, B.A.R.C. The Phase Modulated technique provides a faster and more accurate data acquisition process than the conventional ellipsometry. The measured Ellipsometry spectra are fitted with theoretical spectra generated assuming an appropriate model regarding the sample. The fittings have been done objectively by minimising the squared difference (#chi#"2) between the measured and calculated values of the ellipsometric parameters and thus accurate information have been derived regarding the thickness and optical constants (viz, the refractive index and extinction coefficient) of the different layers, the surface roughness and the inhomogeneities present in the layers. Measurements have been done on (i) ion-implanted ...

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

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In this work it is intended a methodology to validate a new version of the software used for monitoring the reactor core, which requires of the evaluation of the thermal limits settled down in the Operation Technical Specifications, for the Unit 2 of Laguna Verde with ARTS (improvements to the APRMs, Rod Block Monitor and Technical specifications). According to the proposed methodology, those are shown differences found in the thermal limits determined with the new versions and previous of the core monitoring software. Author)

British Library Electronic Table of Contents (United Kingdom)

Abstract Purpose: To evaluate the efficacy of transvesical obturator nerve block (ONB) in the prevention of obturator nerve reflex and leg jerking during transurethral resection of bladder tumors (TURBT). Patients and Methods: A total of 60 patients were studied, in whom the transurethral resection of tumors on the posterolateral bladder wall were performed under spinal anesthesia (SA). The patients were randomly divided into two groups. In the first group, we performed transvesical ONB and SA together, while the second group received only SA. The patients underwent TURBT using monopolar cautery. Incidence of leg jerking was registered and compared in these two groups. We used a nerve stimulator to detect the obturator nerve next to the lateral bladder wall. The obturator nerve was identif...

British Library Electronic Table of Contents (United Kingdom)

The need for alternative energy increases steadily???especially due to the climate change and the limited availability of fossil fuels. Geothermal power uses the intrinsic heat which is stored in the accessible part of the Earth???s crust. Its importance among the renewable energy resources originates from the almost unlimited energy supply of the Earth and its independence from external influences such as seasonal or even daily climatic variability. Nevertheless, there are risks which have to be assessed. From a mathematical point of view there are four building blocks of the characterization of deep geothermal systems: seismic exploration, gravimetry, modeling transport processes, and modeling the stress field. In particular, local depletion poses a significant risk during the industrial...

British Library Electronic Table of Contents (United Kingdom)

It has been considered that dry-out occurs easily in boiling heat transfer for a small channel, a mini- or microchannel, because the channel was easily filled with coalescing vapor bubbles. In the present study, the experiments of subcooled flow boiling of water were performed under atmospheric conditions for a horizontal rectangular channel for which the size is 1 mm height and 1 mm width, with a flat heating surface of 10 mm length and 1 mm width placed on the bottom of the channel. The heating surface has a top of copper heating block and is heated by ceramic heaters. In the high heat flux region of nucleate boiling, about 70-80% of the heating surface was covered with a large coalescing bubble and the boiling reached critical heat flux as observed by high-speed video. In the beginning ...

CERN Document Server

The analysis of images (of obtained in various ranges of the lengths of waves) of luminous objects in the Universe by means of a method of multilevel dynamic contrasting led author to the conclusions: a) the structures of all observable galaxies represents a complicated constructions which have the tendency to self-similarity and made of separate (basic) blocks, which are a coaxially tubular structures and a cartwheel-like structures; b) the majority of observable objects in the Universe are luminous butt-ends of almost invisible (of almost completely transparent) of filamentary formations which structures are seen only near to their luminous butt-ends; c) the result of analysis of images of cosmic objects show the structure of many pairs of cooperating galaxies point to opportunity of their formation at butt-ends generated in a place of break of the similar filament; d) the interacting galaxies (M 81 and M 82) show they are butt-ends of sawed off of two branches ...

Science.gov (United States)

The understanding of transport processes that occur in naturally fractured geothermal systems is far from being complete. Often, evaluation and numerical simulations of fractured geothermal reservoirs, are carried out by assuming equivalent porous media and homogeneous petrophysical properties within big matrix blocks. The purpose of this paper, is to present a comparison between results obtained from numerical studies of a naturally fractured reservoir treated as a simple porous medium and the simulation of some real aspects of the fractured reservoir. A general conclusion outlines the great practical importance of considering even approximately, the true nature of such systems. Our results show that the homogeneous simplified evaluation of the energy resource in a fractured system, could result in unrealistic estimates of the reservoir capacity to generate electricity.

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For a solar cell, in order to minimize the loss of incident light, transparent glass or plastic material is used at the incident part. When a solar cell is watched from the light incident part, a silicon base material is directly observed with either block or brown color only. This invention enables a solar cell to give brighter color on the incident surface by placing a reflective film which reflects only the light of specific wavelength, without reducing the efficiency of the solar cell. This reflective film consists of multi-layered dielectric with 12 layers and alternative combination of highly refractive and less refractive substances. Highly refractive layer is Y/sub 2/O/sub 3/ with refractive index 1.74 and the less refractive layer is SiO/sub 2/ with refractive index 1.45. (5 figs)

British Library Electronic Table of Contents (United Kingdom)

This study correlates the post start cell performance and impedance with the cold start process in the subzero environment. The sequential failed cold starts are deliberately conducted as well as the start at small current density. Here the failed cold start means the cell voltage drops to or below zero within very short time during the start process. It is found that there are reversible performance losses for the sequential failed cold starts, while not obvious degradation and no recovery happen for the start at small current density. Using the thin film and agglomerate model, it is confirmed that this is due to the water blocking effect. Comparing the results from different start processes, a model with respect to the shifting of reactive region within the catalyst layer is applied to e...

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

Measurements are presented of indoor radon levels made in a prototype house constructed partly of bauxite waste (red mud) and partly of conventional materials. The mud used contains higher than the average amounts of "2"2"6Ra and "2"3"2Th found in local building materials. The rates of exhalation of radon from the material used in the construction of the house are measured and employed with measured air change rates to make estimates of the average contribution of the various materials to the measured radon levels indoors. There is fairly good agreement between the two. The increment of radon related dose equivalents above background are also estimated and these are combined with previously determined gamma dose equivalents and used as a basis for assessing the acceptability of the practice of using red mud as a building material. (author)

Energy Technology Data Exchange (ETDEWEB)

The possibility of controlling the radial electric field of toroidal plasmas by injecting high energy electrons along the reversible loss cone orbit of the helical magnetic traps is investigated. It is well known that the radial electric field plays an important role in the confinement improvement scenario especially in the low collisional regime under the physics picture of neoclassical theory. For this purpose, it is made clear that the most suitable particles are transit particles, which show a transition from helically trapped orbits to blocked ones. It is also found that a parallel AC electric field launched from outside assists this transition and makes it possible for particles to penetrate deeply into the plasma. In addition we clarify that the viscosity of the plasma coupled with the helical field configuration provide a bifurcation of plasma states and its stable solution results in confinement improvement. (author)

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Protein kinase C activity has been identified in the rat brown adipocyte. About 60% of this activity is found in the cytosolic fraction under basal conditions, and 12-O-tetradecanoylphorbol 13-acetate (TPA) causes a rapid shift from the cytosol to the particulate fraction. Norepinephrine and phenylephrine causes a similar redistribution that can be blocked by prazosin but not by alprenolol. {alpha}{sub 1}-Adrenergic agonists cause three- to fivefold stimulation of type 2 iodothyronine 5{prime}-deiodinase activity in brown adipocytes. TPA has no effect on basal deiodinase activity and reduces the response of the enzyme to {alpha}{sub 1}-adrenergic agonists. These results suggest that the translocation of protein kinase C from cytosol to particulate fraction is not sufficient to increase deiodinase activity but can modulate the {alpha}{sub 1}-adrenergic agonist-mediated responses in these cells.

Science.gov (United States)

Linearly polarized laser radiation accelerates electrons to very high velocities and these electron form a sheath layer on the rear side of thin targets where preferentially protons are accelerated. When mass-limited targets are used, the lateral transport of the absorbed laser energy is reduced and the accelerating field is enhanced. For targets consisting of two ion species, heavier ions facilitate formation of quasi-monoenergetic bunch of lighter ions. For circularly polarized light, fast electron production is suppressed by the absence of the oscillatory component of the ponderomotive force. Ions are accelerated on the front side by the separation field and very thin foil can be accelerated as one massive quasi-neutral block. As all ion species acquire the same velocity, this acceleration mechanism is preferred for heavier ions.

Energy Technology Data Exchange (ETDEWEB)

This task within the EU R and D for ITER was aimed at the development of basic manufacturing solutions for the high heat flux plasma facing components such as the divertor targets, the baffles and limiters. More than 50 representative small-scale mock-ups have been manufactured with beryllium, carbon and tungsten armour using various joining technologies. High heat flux testing of 20 of these mock-ups showed the carbon mono-blocks to be the most robust solution, surviving 2000 cycles at absorbed heat fluxes of up to 24 MW m{sup -2}. With flat armour tiles rapid joint failures occurred at 5-16 MW m{sup -2} depending on joining technology and armour material. These test results serve as a basis for the selection of manufacturing options and materials for the prototypes now being ordered. (orig.) 11 refs.

International Nuclear Information System (INIS)

The results of an investigation into tailed nuclei (TN) and features of dose dependence on frequency of the binuclear cells with TN in human lymphocyte cultures by cytogenetic block method upon X-ray radiation dose are presented. The frequencies of metaphases with dicentric and ring chromosomes are investigated concurrent with TN formed upon completion of first postradiation mitosis. Frequency of the appearance of binuclear cells with nuclei having outgrowth into the cytoplasmic space and arises after first mitosis in human lymphocyte culture is linear-square dependent on the X-irradiation at doses from 0.0 to 4.0 Gy. Positive correlation between frequency of cells with tailed nuclei and frequency of metaphases of first mitosis having dicentric and rings was established. Apparently, formation such TN is connected with dicentric and rings

British Library Electronic Table of Contents (United Kingdom)

We investigate two routes to obtain negative group velocity bands in two-dimensional phononic crystal structures. The negative dispersion originates from the resonances of sub-wavelength building blocks and as such, the system should be regarded as acoustic metamaterials. The first kind of acoustic metamaterial exhibits effectively negative bulk modulus and negative mass density simultaneously. Monopolar and dipolar Mie resonances are combined to achieve an effective medium with negative refractive index. In particular, we present a double negative metamaterial for airborne sonic waves. We then show that we can obtain negative group velocity from quadrupole resonances, and the result is explained using the quasi-static approximation. The negative dispersion in quadrupole bands cannot be de...

International Nuclear Information System (INIS)

AM-SC1 is a heat treatable magnesium alloy that has been specifically developed to achieve the elevated temperature strength and creep properties necessary for engine block applications. This paper describes the interrelationship between the microstructure and the mechanical properties of AM-SC1. The compressive and tensile strengths are relatively insensitive to temperature up to and including 450 K and the tensile yield behaviour deviates from a standard Hall-Petch relationship at grain sizes below 200 ?m. The microstructural features contributing to the creep resistance are both inter- and intra-granular in nature and are on length scales from nanometers to micrometers. The creep behaviour at 423 K and 450 K is diffusion controlled, with any contribution from the grain boundaries being negligible.

International Nuclear Information System (INIS)

A radiometric method of measuring the ratio of liquid and solid phases (crust thickness) in a continuous ingot for automation of the continuous steel casting process, has been proposed. The essence of the method is, that radiation flux, bearing information on the object tested, is transformed in a succession of electric pulses, which is processed afterwords for obtaining necessary information. In this case either the flux of non-scattered radiation, passed through the object, or the flux of single-scattered radiation reflected from the object is registered. Block-diagram and specifications of a radiometric device with the Co source of 50 gxequiv. Ra activity developed for this purpose are presented. The technique for calibration ob the device and the results of its tests, are described. It is shown, that introduction of such devices for the control crust thickness at the installations of continuous steel casting of metallurgical works would permit to exercise ...

Energy Technology Data Exchange (ETDEWEB)

In this report we present a suite of subroutines for the solution of sparse unsymmetric sets of linear equations using a variant of Gaussian elimination. The subroutines are divided into three distinct phases. The first phase optionally preorders the matrix to block triangular form and then performs a sparsity oriented factorization, the second factorizes a matrix of a similar sparsity pattern, while the third uses these decompositions to solve the equations. In this revised edition, the actual Fortran listings have been replaced by a reference to their availability in machine readable form. Other changes to the first edition are minor. This revision is essentially a reprint of the 1979 revision, the only changes being that the MA28A specification sheet has been typeset and has a few minor changes and the existence of a version of the package for complex equations is announced. 11 refs., 11 tabs.

International Nuclear Information System (INIS)