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991.
Karen R. Maxcy Randy Smith Roger D. Willett Ashwani Vij 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e454-e454
The title compound, [NiCl2(C6H8N2)2], contains centrosymmetric molecules with two phenylenediamine ligands coordinated in a bidentate fashion. The Ni—N distances are 2.088 (1) and 2.096 (1) Å, and the Ni—Cl distance of 2.4635 (4) Å. The plane of each phenylenediamine molecule makes a dihedral angle of 26.53 (7)° with the NiN4 plane. Extensive hydrogen bonding leads to distinct cleavage in the bc plane. 相似文献
992.
[reaction: see text] A new one-pot procedure for the synthesis of substituted pyrrolidine derivatives with commercially available cyclopropyl ketones, aldehydes, and amines by a metal iodide promoted three-component reaction was developed. 相似文献
993.
Min M Wang L Li Y Mohr MJ Hu B Zhou W Chen P Ruan R 《Applied biochemistry and biotechnology》2011,165(1):123-137
This study is concerned with a novel mass microalgae production system which, for the first time, uses “centrate”, a concentrated
wastewater stream, to produce microalgal biomass for energy production. Centrate contains a high level of nutrients that support
algal growth. The objective of this study was to investigate the growth characteristics of a locally isolated microalgae strain
Chlorella sp. in centrate and its ability to remove nutrients from centrate. A pilot-scale photobioreactor (PBR) was constructed at
a local wastewater treatment plant. The system was tested under different harvesting rates and exogenous CO2 levels with the local strain of Chlorella sp. Under low light conditions (25 μmol·m-2s-1) the system can produce 34.6 and 17.7 g·m-2day-1 biomass in terms of total suspended solids and volatile suspended solids, respectively. At a one fourth harvesting rate,
reduction of chemical oxygen demand, total Kjeldahl nitrogen, and soluble total phosphorus were 70%, 61%, and 61%, respectively.
The addition of CO2 to the system did not exhibit a positive effect on biomass productivity or nutrient removal in centrate which is an organic
carbon rich medium. The unique PBR system is highly scalable and provides a great opportunity for biomass production coupled
with wastewater treatment. 相似文献
994.
Mancey NC Sandon N Auvinet AL Butlin RJ Czechtizky W Harrity JP 《Chemical communications (Cambridge, England)》2011,47(35):9804-9806
The enantiospecific and diastereocontrolled total synthesis of alkaloid (-)-217A is described that employs a stepwise [3+3] annelation strategy and a piperidine 2,3-cyclopropanation-ring opening reaction as the key steps. 相似文献
995.
We study the equation with a discontinuous nonlinearity: ?Δu = λH(u ? 1) (H is Heaviside's unit function) in a square subject to various boundary conditions. We expect to find a curve dividing the harmonic (Δu = 0) region from the superharmonic (Δu = ?λ) region, defined by the equation u(x, y) = 1. This curve is called the free boundary since its location is determined by the solution to the problem. We use the implicit function theorem to study the effect of perturbation of the boundary conditions on known families of solutions. This justifies rigorously a formal scheme derived previously by Fleishman and Mahar. Our method also discovers bifurcations from previously known solution families. 相似文献
996.
Let be an exact C∗-algebra, let G be a locally compact group, and let be a C∗-dynamical system. Each automorphism αg induces a spatial automorphism Adλg on the reduced crossed product . In this paper we examine the question, first raised by E. Størmer, of when the topological entropies of αg and Adλg coincide. This had been answered by N. Brown for the particular case of discrete abelian groups. Using different methods, we extend his result to preservation of entropy for αg when the subgroup of Aut(G) generated by the corresponding inner automorphism Adg has compact closure. This property is satisfied by all elements of a wide class of groups called locally [FIA]−. This class includes all abelian groups, both discrete and continuous, as well as all compact groups. 相似文献
997.
D.Roger Willis 《International Journal of Non》1982,17(1):63-65
The results of Van der Pol and Strutt [Phil. Mag.5, 18 (1928)] on the stability of solutions to the Hill equation for a square-wave coefficient have been re-examined. More accurate and extensive results for the stability boundaries are presented, with emphasis on the closed unstable regions which are imbedded in the stable regions. 相似文献
998.
Roger E. Khayat 《国际流体数值方法杂志》2000,34(3):241-275
An adaptive (Lagrangian) boundary element approach is proposed for the general three‐dimensional drop deformation in confined flow. The adaptive method is stable as it includes remeshing capabilities of the deforming interface between drop and suspending fluid, and thus can handle large deformations. Both drop and surrounding fluid are viscous incompressible and can be Newtonian or viscoelastic. A boundary‐only formulation is implemented for fluids obeying the linear Jeffrey's constitutive equation. Similarly to the formulation for two‐dimensional Newtonian fluids (Khayat RE, Luciani A, Utracki LA. Boundary element analysis of planar drop deformation in confined flow. Part I. Newtonian fluids. Engineering Analysis of Boundary Elements 1997; 19 : 279), the method requires the solution of two simultaneous integral equations on the interface between the two fluids and the confining solid boundary. Although the problem is formulated for any confining geometry, the method is illustrated for a deforming drop as it is driven by the ambient flow inside a cylindrical tube. The accuracy of the method is assessed by comparison with the analytical solution for two‐phase radial spherical flow, leading to good agreement. The influence of mesh refinement is examined for a drop in simple shear flow. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
999.
Qihong Chen Delin Chu Roger C.E. Tan 《Nonlinear Analysis: Real World Applications》2011,12(3):1459-1474
This paper is devoted to the state-constrained optimal control problem of evolutionary variational inequality. In this paper, the control domain is not necessarily convex. Moreover, since our state constraint is quite general and, in many cases, it requires pointwise behavior of the state, the framework of the partial differential equation (instead of the abstract framework) is used. Some optimality conditions (in the form of Pontryagin’s principle) for optimal controls are established. 相似文献
1000.