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191.
A cobalt‐containing monodentate phosphine [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(i‐Pr)2] 2f , was prepared from the reaction of (μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)6 1 with PhC≡CP(i‐Pr)2. It was accompanied by an oxidized compound, [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(=O)(i‐Pr2)] 2fo during the chromatographic process. Further reaction of 2f with Mo(CO)6 resulted in the formation of a 2f ‐ligated molybdenum complex 4 , [(μ2‐PPh2CH2PPh2‐κ2P)Co2(CO)4][μ2‐η2‐PhC≡CP(i‐Pr2)‐κP]‐Mo(CO)5. 相似文献
192.
Fan Fu 《Tetrahedron letters》2006,47(25):4267-4269
A chiral indium(III) complex prepared from indium triflate and a pybox ligand has been developed to give good yields and enantioselectivities (up to 92% ee) in the addition of (1-methoxy-2-methyl-propenyloxy)-trimethylsilane to various aromatic and aliphatic aldehydes via the Mukaiyama aldol reaction. 相似文献
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194.
Antimonide-based superlattices dedicated to the elaboration of opto-electronic devices have been studied by X-ray scattering techniques. In particular, specular and non-specular X-ray reflectometry experiments have been performed on two MBE-samples elaborated with different shutter sequences at the interfaces. The results have shown a limitation of the incorporation of Sb species in the subsequent InAs layer for one of the samples, as expected.Then, a study on a InGaAs-cap layer/(InGaAs/AlAsSb)N superlattice grown on a InGaAs/InP buffer layer by both specular X-ray reflectometry and High resolution X-ray diffraction is reported. In particular, the results have revealed the presence of a highly disturbed thin-layer on top of the MOVPE-made GaInAs, whose presence has been explained by In-concentration modification during the desoxidation procedure at the surface of the MOVPE-made GaInAs.Beside the results on the Sb-based heterostructures, the use of X-ray scattering metrology as a routinely working non-destructive testing method has been emphasized. 相似文献
195.
196.
Hanna Sandler 《Geometriae Dedicata》1998,69(3):317-327
In this paper it is shown that one can choose an arbitrarily large number of inconjugate elements of the group Z/2Z*Z/2Z*Z/2Z which have the property that, under all representations of the group in SU(2,1) as a discrete complex hyperbolic ideal triangle group, the elements are hyperbolic and correspond to closed geodesics of equal length on the associated complex hyperbolic surface. This is an analogue of the geometric fact that the multiplicity of the length spectrum of a Riemann surface is never bounded or the equivalent algebraic phenomenon that an arbitrarily large number of conjugacy classes in a free group can have the same trace under all representations in SL(2,R ). 相似文献
197.
EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
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199.
We present a new algorithm for the identification of ring pairs in Cherenkov detectors. The approach combines linear regression methods for the construction of an appropriate reference quantity, methods from statistics for the evaluation of hypotheses and Monte Carlo simulation runs for the tuning of threshold levels. 相似文献
200.
Klaus Ziegler 《Journal of multivariate analysis》1997,62(2):233-272
Functional central limit theorems for triangular arrays of rowwise independent stochastic processes are established by a method replacing tail probabilities by expectations throughout. The main tool is a maximal inequality based on a preliminary version proved by P. Gaenssler and Th. Schlumprecht. Its essential refinement used here is achieved by an additional inequality due to M. Ledoux and M. Talagrand. The entropy condition emerging in our theorems was introduced by K. S. Alexander, whose functional central limit theorem for so-calledmeasure-like processeswill be also regained. Applications concern, in particular, so-calledrandom measure processeswhich include function-indexed empirical processes and partial-sum processes (with random or fixed locations). In this context, we obtain generalizations of results due to K. S. Alexander, M. A. Arcones, P. Gaenssler, and K. Ziegler. Further examples include nonparametric regression and intensity estimation for spatial Poisson processes. 相似文献