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991.
Bernhard Peters 《Journal of Analytical and Applied Pyrolysis》2011,91(2):352-358
The objective of this contribution is to describe thermal degradation of Miscanthus giganteus by a detailed reaction mechanism. It includes degradation kinetics for cellulose, hemicellulose and lignin which constitute the major mass fractions of M. giganteus. Furthermore, the mechanism yields a detailed composition of product gases, and is therefore well-suited to predict evolution of both thermal decomposition and products. Therefore, the reaction mechanism was introduced to the Discrete Particle Method (DPM) that solves the coupled differential conservation equations for mass, momentum, species, and energy for a M. giganteus particle. Predicted results were compared to experimental data and yielded good agreement. 相似文献
992.
Nawn G Waldie KM Oakley SR Peters BD Mandel D Patrick BO McDonald R Hicks RG 《Inorganic chemistry》2011,50(20):9826-9837
Reactions of indigo with a variety of substituted anilines produce the corresponding indigo diimines ("Nindigos") in good yields. Nindigo coordination complexes are subsequently prepared by reactions of the Nindigo ligands with Pd(hfac)(2). In most cases, binuclear complexes are obtained in which the deprotonated Nindigo bridges two Pd(hfac) moieties in the expected bis-bidentate binding mode. When the Nindigo possesses bulky substituents on the imine (mesityl, 2,6-dimethylphenyl, 2,6-diisopropylphenyl, etc.), mononuclear Pf(hfac) complexes are obtained in which the Nindigo core has isomerized from a trans- to a cis-alkene; in these structures, the palladium is bound to the cis-Nindigo ligand at the two indole nitrogen atoms; the remaining proton is bound between the imine nitrogen atoms. The palladium complexes possess intense electronic absorption bands [near 920 nm for the binuclear complexes and 820 nm for the mononuclear cis-Nindigo complexes; extinction coefficients are (1.0-2.0) × 10(4) M(-1) cm(-1)] that are ligand-centered (π-π*) transitions. Cyclic voltammetry investigations reveal multiple redox events that are also ligand-centered in origin. All of the palladium complexes can be reversibly oxidized in two sequential one-electron steps; the binuclear complexes are reduced in a two-electron process whose reversibility depends on the Nindigo ligand substituent; the mononuclear palladium species show two one-electron reductions, only the first of which is quasi-reversible. 相似文献
993.
994.
Karl M. Peters 《代数通讯》2013,41(12):4807-4826
In this paper, we analyze the characters of modular, irreducible rep-resentations of classical Lie algebras g of types Al-1 and Ci arising from a characteristic 0 construction of torsion free representations. By character, we refer to linear functionals on g identified with algebra homomorphisms from a distinguished central subalgebra O of the universal enveloping algebra of g. If Lie(G') = g, then for each character X standard representatives with respect to a fixed toral subalgebra are found in the (2-orbit containing the character X For many parameters, these characters are nilpotent. Furthermore, modular representations of type Al-1 and type Cl Lie algebras constructed by induction from these irreducible, torsion free representations are shown to admit characters in a family of both Richardson and non-Richardson nilpotent orbits. Through this explicit induction construction, irreducible representations of minimal p-power dimension under the Kac-Weisfeiler conjecture are realized 相似文献
995.
Abstract We applied a mass spectrometric method, developed by Itada and Forster [1] for erythrocyte suspensions, which observes the exchange of 18O between HCO3 ?, CO2 and H2O, to determine intracellular carbonic anhydrase activity, A i , and bicarbonate permeability, P, in intact guinea pig colon epithelium. To study the validity of the results with intact distal and proximal colon epithelia, we compared them with measurements of Ai and P in suspensions of isolated epithelial cells from the distal and proximal guinea pig colon. In both parts of the colon there is good agreement between the Ai values of colonocytes in suspension and in the intact colon epithelium. In addition we tested the temperature dependence of Ai and P, the oxygen supply to the colon during the measurements, and the intactness of the epithelial cells by trypan blue staining. We conclude that it is valid to use the method of Itada and Forster [1] with intact colon epithelial sheets. This new application allows us to study separately the apical and serosal membrane of the epithelial cells. We used the method to determine whether there is a short chain fatty acid – bicarbonate exchanger in the apical or serosal membrane of proximal and distal colon epithelium. For this purpose we measured the membrane bicarbonate permeability in the presence and absence of 25 mM propionate in the reaction solution. Only in the apical membrane of the proximal colon we find a higher P in presence of propionate than in its absence, showing that there the transport of short chain fatty acids is coupled to that of bicarbonate. 相似文献
996.
Judith Peters Marcus Trapp Darren Hughes Steven Rowe Bruno Demé Jean-Luc Laborier 《高压研究》2013,33(1):97-102
The design of new high pressure equipment for structural and dynamical studies on samples in solution is described. We present two sample cells for applying pressures up to 150 and 700 MPa (i.e. 1.5 and 7 kbar), respectively. These cells are mounted on special sticks and inserted into the calorimeter of a cryostat to regulate the temperature. Different parts of the equipment – the pressure controller, the sticks and the cells – are described. In addition, radiography tests which were performed with neutrons in situ at the Institut Laue Langevin to verify the tightness of the cells and the hydrostatic transmission of the pressure to the sample are presented. First results on model lipids are in agreement with former results by R. Winter et al. [Towards an understanding of the temperature/pressure configurational and free-energy landscape of biomolecules, J. Non-Equilib. Thermodyn. 32 (2007), pp. 41–97]. 相似文献
997.
998.
999.
1000.
Privacy Considerations in Participatory Data Collection via Spatial Stackelberg Incentive Mechanisms
Koh Jing Yang Peters Gareth W. Nevat Ido Leong Derek 《Methodology and Computing in Applied Probability》2021,23(3):1097-1128
Methodology and Computing in Applied Probability - Mobile crowd sensing is a widely used sensing paradigm allowing applications on mobile smart devices to routinely obtain spatially distributed... 相似文献