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51.
Frédéric Dumur Eddy Dumas Jérôme Marrot Francis Sécheresse 《Tetrahedron letters》2007,48(23):4143-4146
Efficient strategies for the synthesis of three building-blocks 4′-(functionalized)-2,2′:6′,2″-terpyridine have been developed for the convergent synthesis of metallodendrons; these strategies provide a practical approach for the rational design of highly conjugated metallodendrimers. 相似文献
52.
13C-labeled compounds are often employed as surrogate or internal standards to monitor the performance of extraction and instrumental analysis procedures for their unlabeled counterparts. However, labeled and unlabeled counterparts most often coelute chromatographically with overlapping mass ion fragments, posing a challenge to the accurate quantification of these compounds. In the present study, an analytical scheme, using coeluting unlabeled and 13C-labeled polychlorinated biphenyl (PCB) congeners as the model compounds, was developed with a low-resolution tandem mass spectrometer (MS/MS) to determine the appropriate ranges of PCB congener concentrations that satisfy the no-interference condition. Interferences from unlabeled PCBs to quantitation of labeled counterparts could be minimized when 13C-labeled PCB congeners were quantified in the MS/MS mode within a certain concentration range. In addition, good agreements between the measured and theoretically predicted quantitation errors were observed for all labeled PCB congeners except PCB 180. The exception with labeled PCB 180 was mainly attributed to the occurrence of instrumental analytical uncertainty, as analytical error was also observed with absence of unlabeled PCB 180. These results indicate that MS/MS techniques can serve as a useful tool to minimize interferences with quantitation of isotopically labeled compounds from their unlabeled counterparts, which possess partially overlapping ion fragment profiles. 相似文献
53.
We provide combinatorial as well as probabilistic interpretations for the q-analogue of the Pochhammer k-symbol introduced by Díaz and Teruel. We introduce q-analogues of the Mellin transform in order to study the q-analogue of the k-gamma distribution. 相似文献
54.
Terence C. W. Poon Irene L. Ang Man‐Ki Law Kiwi Y. W. Chan Eddy W. Y. Ng Sai‐Ming Ngai Joseph J. Y. Sung Henry L. Y. Chan 《Electrophoresis》2010,31(10):1721-1730
ProteinChip surface‐enhanced laser desorption/ionization technology and magnetic beads‐based ClinProt system are commonly used for semi‐quantitative profiling of plasma proteome in biomarker discovery. Unfortunately, the proteins/peptides detected by MS are non‐recoverable. To obtain the protein identity of a MS peak, additional time‐consuming and material‐consuming purification steps have to be done. In this study, we developed a magnetic beads‐based proteomic fingerprinting method that allowed semi‐quantitative proteomic profiling and micropreparative purification of the profiled proteins in parallel. The use of different chromatographic magnetic beads allowed us to obtain different proteomic profiles, which were comparable to those obtained by the ProteinChip surface‐enhanced laser desorption/ionization technology. Our assays were semi‐quantitative. The normalized peak intensity was proportional to concentration measured by immunoassay. Both intra‐assay and inter‐assay coefficients of variation of the normalized peak intensities were in the range of 4–30%. Our method only required 2 μL of serum or plasma for generating enough proteins for semi‐quantitative profiling by MALDI‐TOF‐MS as well as for gel electrophoresis and subsequent protein identification. The protein peaks and corresponding gel spots could be easily matched by comparing their intensities and masses. Because of its high efficiency and reproducibility, our method has great potentials in clinical research, especially in biomarker discovery. 相似文献
55.
A highly divergent, flexible, and conceptually simple sequence allowing the parallel solution-phase assembly of functionalized azinone libraries has been developed in a one-pot consecutive fashion. Structural decoration of in situ-generated heterocyclic aza-Michael adducts AB was accomplished by exploiting the diversity potential of Heck, Suzuki, Sonogashira, and Stille reactions. 相似文献
56.
Abdon Eddy Choque Rivero Andreas Lasarow Armin Rahn 《Complex Analysis and Operator Theory》2011,5(2):513-543
By Cayley transformation, there is an interplay between matrix-valued Carathéodory and Schur functions in the unit disk. One of the main aims of the paper is to study this interplay with a view to the fact that the matrix function given by the values of a Carathéodory function via Moore–Penrose inverses is also a Carathéodory function. In doing so, we also analyze ranges and null spaces of the values of the matrix function in question and get some results of independence concerning the concretely chosen point of the domain. 相似文献
57.
Francisco Rego Elwin de Weerdt Eddy van Oort Erik-Jan van Kampen Qiping Chu António M. Pascoal 《Mathematics in Computer Science》2014,8(3-4):425-442
The computation of the reachable set of states of a given dynamic system is an important step to verify its safety during operation. There are different methods of computing reachable sets, namely interval integration, capture basin, methods involving the minimum time to reach function, and level set methods. This work deals with interval integration to compute subpavings to over or under approximate reachable sets of low dimensional systems. The main advantage of this method is that, compared to guaranteed integration, it allows to control the amount of over-estimation at the cost of increased computational effort. An algorithm to over and under estimate sets through subpavings, which potentially reduces the computational load when the test function or the contractor is computationally heavy, is implemented and tested. This algorithm is used to compute inner and outer approximations of reachable sets. The test function and the contractors used in this work to obtain the subpavings involve guaranteed integration, provided either by the Euler method or by another guaranteed integration method. The methods developed were applied to compute inner and outer approximations of reachable sets for the double integrator example. From the results it was observed that using contractors instead of test functions yields much tighter results. It was also confirmed that for a given minimum box size there is an optimum time step such that with a greater or smaller time step worse results are obtained. 相似文献
58.
We report a differential synthetic aperture ladar concept that relaxes platform and laser requirements compared with those for conventional synthetic aperture ladar. Line-of-sight translation-vibration constraints are reduced by several orders of magnitude, while laser frequency stability is typically relaxed by an order of magnitude. The technique is most advantageous for shorter laser wavelengths, ultraviolet to mid-infrared. Analytical and modeling results, including the effect of speckle and atmospheric turbulence, are presented. 相似文献
59.
60.
We find an explicit expression for the cross-covariance between stochastic integral processes with respect to a -dimensional fractional Brownian motion (fBm) with Hurst parameter , where the integrands are vector fields applied to . It provides, for example, a direct alternative proof of Y. Hu and D. Nualart’s result that the stochastic integral component in the fractional Bessel process decomposition is not itself a fractional Brownian motion. 相似文献