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11.
This paper describes the determination of theophylline and guaifenesin in human serum using ion mobility spectrometry with positive corona discharge as source ionization. The optimization of parameters that could influence ion mobility spectrometry was investigated. Under optimum conditions (Temperature; injection: 220 and oven: 175 °C, Flow rate; carrier: 300 and drift: 600 mL min?1, Voltage; corona: 2300 and drift: 7000 V, pulse width: 100 μs), calibration curves were linear in the ranges of 2 to120 and 6 to 120 ng for theophylline and guaifenesin, respectively. The relative standard deviation (n?=?10) was below 12 %. The detection limits were found to be 0.1 ng for theophylline and 0.5 ng for guaifenesin. The recovery results for the theophylline and guaifenesin determination in human serum was about 80 % that indicate the proposed method can be applied for the two drugs analysis in real sample. Furthermore, the proposed method has been evaluated in the simultaneous determination of the two drugs.  相似文献   
12.
A convenient one‐pot four‐component synthesis of tetrasubstituted pyrroles was carried out through the reaction of butane‐2,3‐dione with α‐aminophosphorous ylides, obtained in situ from the 1 : 1 : 1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylate, and ammonium acetate.  相似文献   
13.
A general framework is developed for separating classical and quantum correlations in a multipartite system. Entanglement is defined as the difference in the correlation information encoded by the state of a system and a suitably defined separable state with the same marginals. A generalization of the Schmidt decomposition is developed to implement the separation of correlations for any pure, multipartite state. The measure based on this decomposition is a generalization of the entanglement of formation to multipartite systems, provides an upper bound for the relative entropy of entanglement, and is directly computable on pure states. The example of pure three-qubit states is analyzed in detail, and a classification based on minimal, four-term decompositions is developed.  相似文献   
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15.
We demonstrate that the coupling system of negatively capped CdSe/ZnS QDs with an oxidized Cytochrome c (Cyt c) is capable of the fluorescent imaging of a superoxide radical (O(2)˙?) with high sensitivity and specificity in living cells, without interference from other Reactive Oxygen Species (ROS) or relevant intracellular components.  相似文献   
16.
An exact analysis of two-dimensional massles quantum chromodynamics using functional methods is carried out to determine the strong-coupling, infrared behaviour of the massive case. The theory is reduced to an exact equation whose infrared limit reveals the existence of colored, massive bosons and the absence of a rising potential, with quarks still confined.  相似文献   
17.
Connected autonomous vehicles (CAVs) have the potential to deal with the steady increase in road traffic while solving transportation related issues such as traffic congestion, pollution, and road safety. Therefore, CAVs are becoming increasingly popular and viewed as the next generation transportation solution. Although modular advancements have been achieved in the development of CAVs, these efforts are not fully integrated to operationalize CAVs in realistic driving scenarios. This paper surveys a wide range of efforts reported in the literature about the CAV developments, summarizes the CAV impacts from a statistical perspective, explores current state of practice in the field of CAVs in terms of autonomy technologies, communication backbone, and computation needs. Furthermore, this paper provides general guidance on how transportation infrastructures need to be prepared in order to effectively operationalize CAVs. The paper also identifies challenges that need to be addressed in near future for effective and reliable adoption of CAVs.  相似文献   
18.
The compact and harmonious layout of ads and text is a fundamental and costly step in the production of commercial telephone directories (Yellow Pages). We formulate a canonical version of Yellow-Pages pagination and layout (YPPL) as an optimization problem in which the task is to position ads and text-stream segments on sequential pages so as to minimize total page length and maximize certain layout aesthetics, subject to constraints derived from page-format requirements and positional relations between ads and text. We present a heuristic-search approach to the YPPL problem. Our algorithm has been applied to a sample of real telephone-directory data, and produces solutions that are significantly shorter and better than the published ones.  相似文献   
19.
Graphene oxide(GO) has a wide fluorescence bandwidth,which makes it a prospective candidate for numerous applications.For many of these applications,the fluorescence yield of GO should be further increased.The sp~2-hybridized carbons in GO confine the π-electrons.Radiative recombination of electron-hole pairs in such sp~2 clusters is the source of fluorescence in this material.Palladium nanoparticles are good catalysts for sp~2 bond formations.We report on the preparation of GO,palladium nanoparticles and their nanocomposites in two different solvents.It is shown that palladium nanoparticles can considerably enhance the intrinsic fluorescence of GO in the blue-green part of the visible light spectrum.Fluorescence enhancement has been attributed to the catalytic role of palladium nanoparticles in increasing the number of sp2 bonds of GO with the molecules of the surrounding media.It is shown that palladium nanoparticles could be the nanoparticle of choice for fluorescence enhancement of GO because of their catalytic role in sp2 bond formation.  相似文献   
20.
Oxygen reduction : A polarized water|1,2‐dichloroethane (DCE) interface acts as a proton pump for the [Co(tpp)] (TPP=5,10,15,20‐tetraphenylporphyrinato) catalyzed O2 reduction by ferrocene (Fc) compounds to produce H2O2 (see figure; IT=ion transfer, ET=electron transfer). This system favours the collection of H2O2 by extraction immediately after its formation in DCE to the adjacent water phase.

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