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Huh Jong-Hoon - - 2003
We report electrohydrodynamic instability in nematic liquid crystals found in Hele-Shaw cells. Due to the present cell geometry, the convective structures could be directly visualized as surface or bulk flows. An unexpected structure is observed, which is completely different from the well-known patterns in the standard cells. By using the ...
Das Jagabandhu - - 2003
A series of structurally novel benzothiazole based small molecule inhibitors of p56(lck) was prepared to elucidate their structure-activity relationships (SAR), selectivity and cell activity in the T-cell proliferation assay. BMS-350751 (2) and BMS-358233 (3) are identified as potent Lck inhibitors with excellent cellular activities against T-cell proliferation.
Baxter-Plant Victoria S - - 2003
The surfaces of cells of Desulfovibrio desulfuricans, Desulfovibrio vulgaris and a new strain, Desulfovibrio sp. 'Oz-7' were used to manufacture a novel bioinorganic catalyst via the reduction of Pd(II) to Pd(0) at the cell surface using hydrogen as the electron donor. The ability of the palladium coated (palladised) cells to ...
Carl Shuster
This lesson introduces the cell as the basic structural unit of life, and details modern cell theory. Educational levels: High school, Undergraduate lower division
Bascom Roger A - - 2003
Pex3p is a peroxisomal integral membrane protein required early in peroxisome biogenesis, and Pex3p-deficient cells lack identifiable peroxisomes. Two temperature-sensitive pex3 mutant strains of the yeast Yarrowia lipolytica were made to investigate the role of Pex3p in the early stages of peroxisome biogenesis. In glucose medium at 16 degrees C, ...
Wilson Jean - - 2003
The study sample consisted of 3,869 drivers, split approximately 50/50 between observed cell phone users and those observed not using cell phones (labeled "nonusers"). Cell phone use was determined by a snapshot observation made on city streets. The sample represented 54% of those originally observed, for whom a match was ...
Cohen Joshua T - - 2003
Evidence that cell phone use while driving increases the risk of being involved in a motor vehicle crash has led policymakers to consider prohibitions on this practice. However, while restrictions would reduce property loss, injuries, and fatalities, consumers would lose the convenience of using these devices while driving. Quantifying the ...
Hara Kohjiro - - 2003
We have developed an efficient and novel polyene-dye-sensitized nanocrystalline TiO2 solar cells producing a 6.8% solar energy-to-electricity conversion efficiency (eta) under AM 1.5 irradiation (100 mW cm(-2)): short-circuit current density (Jsc), 12.9 mA cm(-2), open-circuit photovoltage (Voc), 0.71 V, fill factor (ff), 0.74.
Au, Siu Fai
The world's energy consumption is growing extremely rapidly. Fuel cell systems are of interest by researchers and industry as the more efficient alternative to conventional thermal systems for power generation. The principle of fuel cell conversion does not involve thermal combustion and hence in theory fuel cell systems can be ...
Stuckings, M.F.
Optimised solar cell design is dependent on the assumed shading and resistance losses associated with front contacts. In this study, a spectrophotometer with integrating sphere attachment was used to measure the reflection from the front surface of encapsulated silver electroplated front contact solar cells. The results obtained are in good ...
Bert, Wim
The cellular gonoduct structure of 97 species belonging to the Tylenchomorpha and of eight species belonging to outgroups were studied, this to explore diagnostic applications of gonoduct characteristics and their use to assess phylogenetic relationships within the Tylenchomorpha. The morphology of the spermatheca has been shown to have particular value ...
Dietrich, P.
In the attempts to attain greater efficiency of mobility, based in the long-term on renewable energy sources, the efficiency of energy conversion in the vehicle remains an important issue. Polymer electrolyte membrane fuel cell technology has the potential to improve the efficiency of the powertrain for passenger vehicles above the ...
Folkesson, A
Fuel cells produce low quantities of local emissions, if any, and are therefore one of the most promising alternatives to internal combustion engines as the main power source in future vehicles. It is likely that urban buses will be among the first commercial applications for fuel cells in vehicles. This ...
Nygaard, Stian
This thesis is an investigation of innovation in fuel cells and related hydrogen technology in Norway from 1990-2002. The main focus is an analysis of the innovation activities that took place in Norway within the area of fuel cells and related hydrogen technology. Were they a result of cooperation among ...
Ormerod R Mark - - 2003
Despite being first demonstrated over 160 years ago, and offering significant environmental benefits and high electrical efficiency, it is only in the last two decades that fuel cells have offered a realistic prospect of being commercially viable. The solid oxide fuel cell (SOFC) offers great promise and is presently the ...
Gurski, Stephen Daniel
In recent years government, academia and industry have been pursuing fuel cell technology as an alternative to current power generating technologies. The automotive industry has targeted fuel cell technology as a potential alternative to internal combustion engines. The goal of this research is to understand and quantify the impact and ...
Wolny Janusz - - 2003
In this paper, the average unit cell for a quasicrystal is constructed by a statistical approach. For the Penrose tiling, it is shown that such a unit cell is fully equivalent to the oblique projection of the atomic surface onto physical space. The obtained statistical distributions can be easily extended ...
Ferrigno Rosaria - - 2002
This paper describes the design and characterization of a small, membraneless redox fuel cell. The smallest channel dimensions of the cell were 2 mm x 50 mum or x 200 mum; the cell was fabricated in poly(dimethylsiloxane) using soft lithography. This all-vanadium fuel cell took advantage of laminar flow to ...
Mamak Marc - - 2002
Solid oxide fuel cells comprised of an anode made from sintered and reduced mesoporous-NiO-YSZ are shown to provide stable current and power densities at the operating temperature of 800 degrees C and show better performance than cells with anode cermets made from mechanical mixtures of NiO and YSZ, attributable to ...
Morgan E
This project was undertaken to explore the possible intersection between two promising technologies: biomass energie conversion and fuel cells. This report focuses on seven such conversion technologies and the bio-based fuels they produce: syngas from biomass gasification: landfill gas: digester gas: ethanol: pyrolysis oil: biodiesel: and MTHF from levulinic acid.
Grant Kenneth - - 2002
Laser capture microdissection uses a microscope to identify specific cells for microdissection and then a laser-sensitive plastic to capture and remove the cells from their substrate. This efficient capture method was originally developed to capture cells for genetic analysis. However, it has also been used to capture cells for proteonomic ...
Shahabuddin Mohammed - - 2002
Recent debate in Plasmodium ookinete invasion has been centered on whether the parasite chooses a specific cell type to cross the midgut epithelium in the mosquito. A few publications have described the mosquito midgut being composed of complex surface-structures, histochemically and biochemically diverse cell types, and have proposed that Plasmodium ...
Sunil Arya,Theocharis Malamatos,David M. ...
a (t; ffl)-approximate Voronoi diagram (AVD) is a partition of space into constant complexity cells, where each cell c is associated with t representative points of S, such that for any point in c, one of the associated representatives approximates the nearest neighbor to within a factor of (1 + ...
Queisser, H.-J.
Reducing the geometric dimensionality in a photovoltaic cell is useful in designing optimal contact geometry, in enhancing the conversion efficiency by enlarging the concentrations of photogenerated carriers and, generally, by utilizing thin-film structures for solar cells. It is not yet obvious whether or not dimensions in the range of nanometers ...
Meier, J.
Intrinsic microcrystalline silicon opens up new ways for silicon thin-film multi-junction solar cells, the most promising being the "micromorph" tandem concept. The microstructure of entirely microcrystalline p-i-n solar cells is investigated by transmission electron microscopy. By applying low pressure chemical vapor deposition ZnO as front TCO in p-i-n configurated micromorph ...
Shah, A.
The case for thin-film silicon as one of the main future options for cost-effective photovoltaic solar cells is outlined. The limitations of present amorphous silicon (a-Si:H) solar cells are briefly mentioned. Hydrogenated microcrystalline silicon (μc-Si:H) deposited by PECVD (plasma-enhanced chemical vapor deposition) at low substrate temperatures (approx. 200 °C) constitutes ...
Green, M.A.
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2001 are reviewed.
Selimovic, Azra
An improved design of fuel cells stacks arrangement has been suggested before for MCFC where reactant streams are ducted such that they are fed and recycled among multiple MCFC stacks in series. By networking fuel cell stacks, increased efficiency, improved thermal balance, and higher total reactant utilisation can be achieved. ...
Karlsson, Lina
Lina Karlsson, Benoît Lafitte, and Patric Jannasch, oral presentation at the NorFA workshop “Frontiers in Battery and Fuel Cell Research”, Uppsala, June, 2002.
Huljic, D. M.
Pad printing represents a promising technique having the potential to outperform conventional screen printing regarding technological and economical aspects. As this technique is based on metallisation pastes, pad printed contacts are compatible with present industrial solar cell production. Focusing on front contacts, line widths down to ~30 µm have been ...
Jooß, Wolfgang
This thesis examines multicrystalline silicon (mc-Si) as well as back contact silicon solar cells applying the Buried Contact Solar Cell (BCSC) technology. In this metallisation approach, the electrical contacts are buried into the silicon wafer leading to low shadowing losses in conjunction with highly conducting contact fingers. Further features include ...
Bau, S.
Lock-in thermography has been applied for shuntanalysis on epitaxial silicon thin-film solar cells. The solar cell material was made by epitaxial deposition of the base layer on highly doped monocrystalline (Czochralski) and multicrystalline silicon substrates in an APCVD-system. Solar cells were prepared in a laboratory-type and an industrial-type process. Characterization ...
Willeke, G.P.
A 50 mu m thin layer of high quality crystalline silicon together with efficient light trapping and well passivated surfaces is in principle all that is required to achieve stable solar cell efficiencies in the 20% range. In the present work, we propose to obtain these layers by directly cutting ...
Durose, K.
Recent developments in the following areas are briefly reviewed: a) the electrical structure of grain boundaries in CdTe absorbers, b) impurities and non-stoichiometry in CdTe solar cells and c) use of Sb2Te3 in contacts to CdTe. Nominally identical solar cells fabricated using 99.999% pure CdTe feedstock from two different suppliers ...
Schriber, Stanley O
RF structures for linear accelerators and synchrotrons are employing full-cell terminated cavities operating in the p-mode more often than in the past. This p-mode selection is based mainly on performance improvements achieved for superconducting cavities and the economics associated with superconducting cavities in large facilities. An understanding of critical system ...
Kruszewski, Eric
The largest cost in manufacturing PEM fuel cells for automotive applications is due to the bipolar plate. The current graphite material used for the bipolar plate is very brittle and difficult to machine to the rigorous specifications needed for fuel cell stacks. This paper introduces the development of a fuel ...
The nearest neighbor condition implies that when searching for a mean-square optimal fixed-rate quantizer it is enough to consider the class of regular quantizers, i.e., quantizers having convex cells and code points which lie inside the associated cells. In contrast, quantizer regularity can preclude optimality in entropy-constrained quantization.
Härkönen, Jaakko
Fabrication technology of high efficiency silicon solar cells has been studied in this work. Process development work has been carried out since 1997 within a project "Development of high-efficiency low-cost silicon solar cells", which was funded by TEKES, Fortum Advanced Energy Systems and Okmetic Ltd. Co - operation with photovoltaic ...
Jadhav S - - 2001
The change in the neurosecretory cells with males with respect to seasons was investigated. The brain is provided with three types of neurosecretory cells namely A, B and C and thoracic ganglion with four types of neurosecretory cells A, B, C and D. They vary in number and neurosecretory activity ...
Malhas A N - - 2001
Polycystin-1 is a putative 460 kDa membrane protein with a unique structure and is possibly representative of a new family of proteins. Its structure suggests an involvement in cell signalling and cell-matrix interactions. The amino acid sequence of polycystin-1 has to date been predicted from its gene sequence. This, to ...
Thomas Erickson
aware systems detect a very small set of cues, typically quantitative variations of the few dimensions for which they have sensors. A (hypothetical) context-aware cell phone might be able to detect that it is motionless and in a dark place with high ambient noise but that is very different from ...
Oyarzabal, Borja
The application of a decomposition methodology to the synthesis/design optimization of a stationary cogeneration fuel cell sub-system for residential/commercial applications is the focus of this work. To accomplish this, a number of different configurations for the fuel cell sub-system are presented and discussed. The most promising candidate configuration, which combines ...
Im D S - - 2001
Globoid cell leukodystrophy (GLD) is characterized histopathologically by apoptosis of oligodendrocytes, progressive demyelination, and the existence of large, multinuclear (globoid) cells derived from perivascular microglia. The glycosphingolipid, psychosine (d-galactosyl-beta-1,1' sphingosine), accumulates to micromolar levels in GLD patients who lack the degradative enzyme galactosyl ceramidase. Here we document that an orphan ...
Carr P A - - 2001
Activity levels of cytochrome oxidase, acid phosphatase, and NADPH diaphorase were examined in the perikarya of immunohistochemically identified Renshaw cells from sections of rat lumbar spinal cord. Renshaw cell profiles were identified on the basis of their characteristic anti-gephyrin-immunofluorescent labelling. Intrasomatic densities of enzyme histochemical reaction product were employed as ...
The market is open for a technology that can meet world energy demands without compromising performance. The fuel cell is the only technology that can meet the existing challenges: it is clean, efficient and versatile. In short, the fuel cell offers a combination of benefits which will ensure it an ...
Konstankiewicz K.
The present study concentrates on the influence of structural parameters of potato tuber tissue on its mechanical properties. Observations of the cell structure were carried out by an optical confocal microscope. Image analysis allowed obtaining parameters describing cell size and cell shape. Image analysis and compression test of the outer ...
Schultz, T.
The direct methanol fuel cell (DMFC) has been discussed recently as an interesting option for a fuel-cell-based mobile power supply system in the power range from a few watts to several hundred kilowatts. In contrast to the favoured hydrogen-fed fuel cell systems (e.g. the polymer electrolyte membrane fuel cell, PEMFC), ...
Dimroth, F.
The use of Ga/sub 1-x/In/sub x/As instead of GaAs as a bottom solar cell in a Ga/sub y/In/sub 1-y/P/Ga/sub 1-x/In/sub x/As tandem structure increases the flexibility of choosing the optimum bandgap combination of materials for a multijunction solar cell. Higher theoretical efficiencies are calculated and different cell concepts are suggested ...
Krupitza G - - 2001
Two hypothetical concepts are discussed as means to cure cancer: 1) extinction of the neoplastic cell pool which forms the tumor and 2) induction of terminal differentiation to park tumor cells in growth arrest (1). Sodium butyrate (NaB) has been shown to promote differentiation of HL-60 cells to mature monocytes ...
Carr P A - - 2000
Peptidergic influences on Renshaw cells were assessed in rat using gephyrin-immunoreactivity, as a Renshaw cell specific marker, in combination with substance P, calcitonin gene-related peptide- and nicotinic acetylcholine receptor-immunolabelling. An average of 3.9 substance P-, and 8.1 calcitonin gene-related peptide-, and 16.3 nicotinic acetylcholine receptor-immunoreactive close contacts or puncta were ...
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