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91.
Dreyfuss JM Jacobs C Gindin Y Benson G Staples GO Zaia J 《Analytical and bioanalytical chemistry》2011,399(2):727-735
Hydrophilic interaction chromatography (HILIC) liquid chromatography/mass spectrometry (LC/MS) is appropriate for all native
and reductively aminated glycan classes. HILIC carries the advantage that retention times vary predictably according to oligosaccharide
composition. Chromatographic conditions are compatible with sensitive and reproducible glycomics analysis of large numbers
of samples. The data are extremely useful for quantitative profiling of glycans expressed in biological tissues. With these
analytical developments, the rate-limiting factor for widespread use of HILIC LC/MS in glycomics is the analysis of the data.
In order to eliminate this problem, a Java-based open source software tool, Manatee, was developed for targeted analysis of
HILIC LC/MS glycan datasets. This tool uses user-defined lists of compositions that specify the glycan chemical space in a
given biological context. The program accepts high-resolution LC/MS data using the public mzXML format and is capable of processing
a large data file in a few minutes on a standard desktop computer. The program allows mining of HILIC LC/MS data with an output
compatible with multivariate statistical analysis. It is envisaged that the Manatee tool will complement more computationally
intensive LC/MS processing tools based on deconvolution and deisotoping of LC/MS data. The capabilities of the tool were demonstrated
using a set of HILIC LC/MS data on organ-specific heparan sulfates. 相似文献
92.
93.
We present a pedagogical treatment of the formalism of continuous quantum measurement. Our aim is to show the reader how the equations describing such measurements are derived and manipulated in a direct manner. We also give elementary background material for those new to measurement theory, and describe further various aspects of continuous measurements that should be helpful to those wanting to use such measurements in applications. Specifically, we use the simple and direct approach of generalized measurements to derive the stochastic master equation describing the continuous measurements of observables, give a tutorial on stochastic calculus, treat multiple observers and inefficient detection, examine a general form of the measurement master equation, and show how the master equation leads to information gain and disturbance. To conclude, we give a detailed treatment of imaging the resonance fluorescence from a single atom as a concrete example of how a continuous position measurement arises in a physical system. 相似文献
94.
While feedback control has many applications in quantum systems, finding optimal control protocols for this task is generally challenging. So-called ‘verification theorems’ and ‘viscosity solutions’ provide two useful tools for this purpose: together they give a simple method to check whether any given protocol is optimal, and provide a numerical method for finding optimal protocols. While treatments of verification theorems usually use sophisticated mathematical language, this is not necessary. In this article we give a simple introduction to feedback control in quantum systems, and then describe verification theorems and viscosity solutions in simple language. We also illustrate their use with a concrete example of current interest. 相似文献
95.
Elisabeth Drexler O. Frhr v. Lupin D. Weihe und P. B. Jacobs 《Fresenius' Journal of Analytical Chemistry》1937,109(3-4):129-135
Ohne Zusammenfassung 相似文献
96.
A first-principles analysis reveals that the catalytic efficiency of nitroxyl radicals in alkane oxidations is not simply correlated with their reactivity toward the substrate. 相似文献
97.
To investigate the influence of the anisotropic part of the potential, exact quantum mechanical calculations have been performed of the differential co 相似文献
98.
99.
The spatial distribution of ozone and of oxygen atoms was studied along the active and the passive zone of a dc discharge (positive column, pressure: p = (4 … 10) · 102 Pa, current: I = 2 … 50 mA, flow rate: F = 5 … 100 sccm) in flowing oxygen. The composition of the final output O2/O3-mixture is controlled by relaxation processes in the passive reactor zone. It is affected sensitively by the total number density and the gas temperature in the afterglow. Steady states meaning reversible chemical quasi-equilibria were observed and analysed extensively. Within a detailed kinetic model the formation of these equilibria can be explained quantitatively. The synthesis to ozone is controlled above all by the metastable O2 (a1Δg) species, which modify drastically the results for the basic mechanism, considering the O atoms in the 3P and 1D states. 相似文献
100.
Herein, we demonstrate that the chain-initiating dissociation of cyclohexyl hydroperoxide, CyOOH, is substantially accelerated by H-bond acceptors (e.g. Teflon), which assist O-O bond breaking by stabilising the leaving *OH radical. This is a completely new approach to boost the chain-propagating radical concentration. Indeed, up to now, literature has remained focussed on transition metal catalysis. In addition to this initiation effect, we demonstrate how inert perfluorinated compounds are also able to steer the selectivity at the molecular level, by promoting the conversion of the intermediate cyclohexyl hydroperoxide to the most desired end-product, cyclohexanone. This effect is explained by an enhanced, H-bond-assisted, hydroperoxide propagation. This hitherto overlooked hydroperoxide propagation was recently presented by us as the dominant cyclohexanone and cyclohexanol source. We herein thus confirm our previously reported autoxidation scheme, and illustrate its usefulness as a solid basis for designing new catalytic systems. 相似文献