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991.
In this paper, the spectral shape of the collision induced scattering is calculated in the dipole-induced-dipole approximation for the Raman symmetric vibrational band of optically isotropic molecules. Comparison is made with Rayleigh results. Experimental data for Rayleigh and v 1 Raman band of CF4 are discussed. 相似文献
992.
Highly Axial Magnetic Anisotropy in a N3O5 Dysprosium(III) Coordination Environment Generated by a Merocyanine Ligand 下载免费PDF全文
Pramila Selvanathan Gang Huang Thierry Guizouarn Dr. Thierry Roisnel Dr. Guglielmo Fernandez‐Garcia Dr. Federico Totti Dr. Boris Le Guennic Dr. Guillaume Calvez Dr. Kévin Bernot Dr. Lucie Norel Prof. Stéphane Rigaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15222-15226
A spiropyran‐based switchable ligand isomerizes upon reaction with lanthanide(III) precursors to generate complexes with an unusual N3O5 coordination sphere. The air‐stable dysprosium(III) complex shows a hysteresis loop at 2 K and a very strong axial magnetic anisotropy generated by the merocyanine phenolate donor. 相似文献
993.
994.
Insertion Reactions of Neutral Phosphidozirconocene Complexes as a Convenient Entry into Frustrated Lewis Pair Territory 下载免费PDF全文
Dr. Adrien T. Normand Dr. Gerald Kehr Prof. Pierre Le Gendre Prof. Gerhard Erker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):4285-4293
Neutral phosphidozirconocene complexes [Cp2Zr(PR2)Me] (Cp=cyclopentadienyl; 1a : R=cyclohexyl (Cy); 1b : R=mesityl (Mes); 1c : R=tBu) undergo insertion into the Zr?P bond by non‐enolisable carbonyl building blocks (O=CR′R′′), such as benzophenone, aldehydes, paraformaldehyde or CO2, to give [Cp2Zr(OCR′R′′PR2)Me] ( 3 – 7 ). Depending on the steric bulk around P, complexes 3 – 7 react with B(C6F5)3 to give O‐bridged cationic zirconocene dimers that display typical frustrated Lewis pair (FLP)/ambiphilic ligand behaviour. Thus, the reaction of {[Cp2Zr(μ‐OCHPhPCy2)][MeB(C6F5)3]}2 ( 10a ) with chalcone results in 1,4 addition of the Zr+/P FLP, whereas the reaction of {[Cp2Zr(μ‐OCHFcPCy2)][MeB(C6F5)3]}2 ( 11a ; Fc=(C5H4)CpFe) with [Pd(η3‐C3H5)Cl]2 yields the unique Zr?Fe?Pd trimetallic complex 13a , which has been characterised by XRD analysis. 相似文献
995.
996.
997.
Zaixin Lu Lidong Wu Panos M. Pardalos Eugene Maslov Wonjun Lee Ding-Zhu Du 《Optimization Letters》2014,8(2):425-434
In wireless networks, Connected Dominating Sets (CDSs) are widely used as virtual backbones for communications. On one hand, reducing the backbone size will reduce the maintenance overhead. So how to minimize the CDS size is a critical issue. On the other hand, when evaluating the performance of a wireless network, the hop distance between two communication nodes, which reflect the energy consumption and response delay, is of great importance. Hence how to minimize the routing cost is also a key problem for constructing the network virtual backbone. In this paper, we study the problem of constructing applicable CDS in wireless networks in terms of size and routing cost. We formulate a wireless network as a Disk-Containment Graph (DCG), which is a generalization of the Unit-Disk Graph (UDG), and we develop an efficient algorithm to construct CDS in such kind of graphs. The algorithm contains two parts and is flexible to balance the performance between the two metrics. We also analyze the algorithm theoretically. It is shown that our algorithm has provable performance in minimizing the CDS size and reducing the communication distance for routing. 相似文献
998.
A novel synthesis of highly enantioenriched dipeptides containing homophenylalanine is described. The process involves a crystallisation-induced asymmetric transformation (CIAT) in a Michael addition followed by exhaustive reduction. A unique example of a formally stereodivergent CIAT in conjugate addition of an achiral N-nucleophile to enantiomerically pure Michael acceptor has been discovered. 相似文献
999.
Tian Lan Huichang Bi Suowen Xu Kang Le Zhiyong Xie Yiwei Liu Heqing Huang 《Biomedical chromatography : BMC》2010,24(10):1075-1083
Sphingosine kinase (SphK) is a key enzyme in modulating the levels of sphingosine 1‐phosphate (S1P) as well as an important enzyme in numerous biological responses. Using C17‐sphingosine as a substrate, we established a rapid, sensitive and highly efficient method for determination of SphK activity by analyzing the product C17‐sphingosine 1‐phosphate (C17‐S1P) using liquid chromatography–tandem mass spectrometry. The standard curve for C17‐S1P was linear over a wide range (10–1000 ng/mL) with correlation coefficient (r2) greater than 0.999. The lower limit of quantification for C17‐S1P was 10 ng/mL. The Km values for C17‐sphingosine and ATP were determined to be 28.17 and 188.5 mM, respectively. More importantly, the SphK activity dramatically increased in cultured HEK 293 cells expressing wild‐type SphK1 as well as cells treated with tumor necrosis factor‐a, a sphingosine kinase activator. In contrast, the SphK activity decreased in cultured HEK 293 cells treated with dimethylsphngosine, a sphingosine kinase inhibitor. In conclusion, this method was sensitive and rapid in the determination of SphK acitivity, providing striking utilities in exploring the sphingosine kinase signaling pathway and screening active compounds targeting SphK activity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
1000.
This study deals with the interpretation of experimental Mueller matrices. The understanding of such a matrix is not straightforward in the case, in particular, of a strongly depolarizing medium, which is therefore disturbed and where relevant pieces of information are often distributed among its various elements. As a result, information data need to be extracted by a decomposition of any Mueller matrix into simple elements to uncouple the existing polarimetric effects. This led us to develop an algorithm in order to characterize any depolarizing, or not, polarimetric system. In addition to differentiating the experimental noise from the intrinsic depolarization of the optical system under study, this algorithm proved to: (i) separate depolarization from birefringence and dichroism and (ii) characterize the isotropic or anisotropic nature of the depolarization. At last, this algorithm was validated through the study of several optical systems with different polarimetric properties. 相似文献