We introduce and study a new spectral sequence associated with a Poisson group action on a Poisson manifold and an equivariant momentum mapping. This spectral sequence is a Poisson analog of the Leray spectral sequenc...
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We introduce and study a new spectral sequence associated with a Poisson group action on a Poisson manifold and an equivariant momentum mapping. This spectral sequence is a Poisson analog of the Leray spectral sequence of a fibration. The spectral sequence converges to the Poisson cohomology of the manifold and has the E-2-term equal to the tensor product of the cohomology of the Lie algebra and the equivariant Poisson cohomology of the manifold. The latter is defined as the equivariant cohomology of the multi-vector fields made into a G-differential complex by means of the momentum mapping. An extensive introduction to equivariant cohomology of G-differential complexes is given including some new results and a number of examples and applications are considered.
With good mechanical and thermal properties, elastomers having appreciable electrical conductivity may potentially be developed as smart materials for applications such as strain sensors, artificial muscles or flexibl...
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With good mechanical and thermal properties, elastomers having appreciable electrical conductivity may potentially be developed as smart materials for applications such as strain sensors, artificial muscles or flexible biosensors. With such applications in mind, the purpose of this study was to investigate the structure-properties relationships of new vulcanised blends of a poly (epichlorohydrin) elastomer (PECH) and electrically-conducting polyaniline dodecylbenzenesulfonate salt (***). ***, synthesised by a published method, was blended with PECH and vulcanised with a commercial sulfur cross-linking agent in an internal mixer. The morphological, mechanical, thermal and electrical properties were examined as a function of the amount of *** in the blends. The electrical conductivities increased with the proportion of polyaniline, showing a low percolation threshold of about 1 wt. % (1.07 vol %) *** (from about 10(-12) to 10(-10) S cm(-1)), and a second stage of percolation around 5 wt.%, ultimately reaching around 3 x 10(-8) S cm(-1). The results from microscopy and other techniques indicated that a mixture of micro- and nano-sized *** particles was dispersed in the elastomer matrix at compositions above 5 wt. % ***. The infrared spectra of vulcanised *** blends showed features of the pure polymers, with some notable peak shifts due to intermolecular interactions between the constituents. Thermal properties of the conductive blends were investigated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The thermal stabilities of the blends were strongly dependent on the ratio of *** to PECH, and the two components inhibited the thermal decomposition of each other. The elastomer's glass transition temperature (T-g) was determined by thermomechanical analysis (TMA);each blend showed only one such transition, at temperatures that increased monotonically with the proportion of *** p
In the USA, filtration, separation and purification company Pall Corp has announced that it has been contracted by the National Renewable Energy Laboratory (NREL) to develop critical filtration and separation processe...
In the USA, filtration, separation and purification company Pall Corp has announced that it has been contracted by the National Renewable Energy Laboratory (NREL) to develop critical filtration and separation processes for a US Department of Energy (DOE) advanced bio-fuels project.
BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase ***,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this *** To determine the ...
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BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase ***,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this *** To determine the potential value of intestinal disaccharidases glucoamylase,maltase,sucrase,and lactase in understanding the etiology and pathogenesis of *** A total of 82 FBD patients were *** to the Rome IV criteria(2016),23 patients had diarrhea-predominant irritable bowel syndrome(IBS),33 had functional diarrhea,10 had constipation-predominant IBS,4 had functional constipation,and 12 had mixed *** Dahlqvist method was used to measure disaccharidase activity in the brush-border membrane of mature enterocytes of the small intestine,in duodenal biopsies obtained during *** Lactase deficiency was detected in 86.5%of patients,maltase deficiency in 48.7%,sucrase deficiency in 50%,and glucoamylase deficiency in 84.1%.The activities of all enzymes were reduced in 31.7%of patients,and carbohydrase deficiency was detected in 63.5%of *** low activity of enzymes involved in membrane digestion in the small intestine was found in 95.2%of *** In 78 of the 82 patients with FBD,gastrointestinal symptoms were associated with disaccharidase deficiency.
Research on sustainable energy sources is crucial for alleviating environmental issues and addressing energy security concerns. This study investigates the utilization of various silk precursors in the hydrogen evolut...
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Research on sustainable energy sources is crucial for alleviating environmental issues and addressing energy security concerns. This study investigates the utilization of various silk precursors in the hydrogen evolution reaction. Waste silk fabric, regenerated silk fibroin film, porous silk fibroin, silk cocoon and degummed silk fibroin were used as precursors to prepare HER electrocatalysts. To investigate the influence of precursor form on catalytic perform9ance, a comparative analysis of the morphology, structure and composition of different materials was conducted. Among various catalysts, waste silk fabric based catalysts exhibit the most excellent catalytic activity, with an overpotential of 113 mV at 10 mA cm(-2) and a Tafel slope of 30.9 mV/dec. Even After 1000 cycles of testing, it still maintains excellent catalytic activity. This study provides insights into the influence of precursor forms on the electrochemical performance of biomass carbon-based catalysts, aiming to inspire further research in this field.
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