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81.
82.
The p‐arsanilic acid (p‐ASA), as an aromatic organoarsenic compounds, had received considerable concerns for their potential toxicity and carcinogenic properties. It was essential to detect p‐ASA with a facile method. In this paper, an europium based fluorescent metal–organic framework (MOF) [Eu2(clhex)·2H2O)]·H2O ( BUC‐69 ) was successfully prepared under hydrothermal conditions with 1,2,3,4,5,6‐cyclohexanehexacarboxylic acid (H6clhex) as organic linker. BUC‐69 displayed superior fluorescence capability to achieve selective and sensitive detection toward p‐ASA in water, which presented the first example of a MOF‐based sensor to detect p‐ASA. BUC‐69 showed excellent chemical stability in solutions under pH ranging from 4 to 12, which makes it be a potential sensor both in acidity and alkalinity condition. Significantly, BUC‐69 performed well in fluorescent sensing of p‐ASA at a low concentration (10?6 M) in the simulated wastewater prepared with real lake water, and the results were comparable to the values detected by Inductively Coupled Plasma Optical Emission Spectrometer (ICP‐OES). The corresponding mechanism of fluorescent sensing toward p‐ASA with BUC‐69 was proposed and affirmed. 相似文献
83.
We theoretically investigate optomechanical force sensing via precooling and quantum noise cancellation in two coupled cavity optomechanical systems.We show that force sensing based on the reduction of noise can be used to dramatically enhance the force sensing and that the precooling process can eifectively improve the quantum noise cancellation.Specifically,we examine the effect of optomechanical cooling and noise reduction on the spectral density of the noise of the force measurement;these processes can significantly enhance the performance of optomechanical force sensing,and setting up the system in the resolved sideband regime can lead to an optimization of the cooling processes in a hybrid system.Such a scheme serves as a promising platform for quantum back-action-evading measurements of the motion and a framework for an optomechanical force sensor. 相似文献
84.
Yae Eun Chong Manting Chiang Kiran Deshpande Simon Haroutounian Leonid Kagan Jong Bong Lee 《Biomedical chromatography : BMC》2019,33(11)
Ondansetron, a widely used antiemetic agent, is a P‐glycoprotein (P‐gp) substrate and therefore expression of P‐gp at the blood–brain barrier limits its distribution to the central nervous system (CNS), which was observed to be reversed by coadministration with P‐gp inhibitors. Tariquidar is a potent and selective third‐generation P‐gp inhibitor, and coadministration with ondansetron has shown improved ondansetron distribution to the CNS. There is currently no reported bioanalytical method for simultaneously quantifying ondansetron with a third‐generation P‐gp inhibitor. Therefore, we aimed to develop and validate a method for ondansetron and tariquidar in rat and human plasma samples. A full validation was performed for both ondansetron and tariquidar, and sample stability was tested under various storage conditions. To demonstrate its utility, the method was applied to a preclinical pharmacokinetic study following coadministration of ondansetron and tariquidar in rats. The presented method will be valuable in pharmacokinetic studies of ondansetron and tariquidar in which simultaneous determination may be required. In addition, this is the first report of a bioanalytical method validated for quantification of tariquidar in plasma samples. 相似文献
85.
Dithienoindophenines: p‐Type Semiconductors Designed by Quinoid Stabilization for Solar‐Cell Applications 下载免费PDF全文
Longbin Ren Dr. Haijun Fan Dazhen Huang Dafei Yuan Prof. Dr. Chong‐an Di Prof. Dr. Xiaozhang Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17136-17140
Compared with the dominant aromatic conjugated materials, photovoltaic applications of their quinoidal counterparts featuring rigid and planar molecular structures have long been unexplored despite their narrow optical bandgaps, large absorption coefficients, and excellent charge‐transport properties. The design and synthesis of dithienoindophenine derivatives (DTIPs) by stabilizing the quinoidal resonance of the parent indophenine framework is reported here. Compared with the ambipolar indophenine derivatives, DTIPs with the fixed molecular configuration are found to be p‐type semiconductors exhibiting excellent unipolar hole mobilities up to 0.22 cm2 V?1 s?1, which is one order of magnitude higher than that of the parent IP‐O and is even comparable to that of QQT(CN)4‐based single‐crystal field‐effect transistors (FET). DTIPs exhibit better photovoltaic performance than their aromatic bithieno[3,4‐b]thiophene (BTT) counterparts with an optimal power‐conversion efficiency (PCE) of 4.07 %. 相似文献
86.
Hao Jiang Daniel P. Robinson René Vidal Chong You 《Computational Optimization and Applications》2018,70(2):395-418
We consider the problem of subspace clustering with data that is potentially corrupted by both dense noise and sparse gross errors. In particular, we study a recently proposed low rank subspace clustering approach based on a nonconvex modeling formulation. This formulation includes a nonconvex spectral function in the objective function that makes the optimization task challenging, e.g., it is unknown whether the alternating direction method of multipliers (ADMM) framework proposed to solve the nonconvex model formulation is provably convergent. In this paper, we establish that the spectral function is differentiable and give a formula for computing the derivative. Moreover, we show that the derivative of the spectral function is Lipschitz continuous and provide an explicit value for the Lipschitz constant. These facts are then used to provide a lower bound for how the penalty parameter in the ADMM method should be chosen. As long as the penalty parameter is chosen according to this bound, we show that the ADMM algorithm computes iterates that have a limit point satisfying first-order optimality conditions. We also present a second strategy for solving the nonconvex problem that is based on proximal gradient calculations. The convergence and performance of the algorithms is verified through experiments on real data from face and digit clustering and motion segmentation. 相似文献
87.
A novel molecularly imprinted method with computational simulation for the affinity isolation and knockout of baicalein from Scutellaria baicalensis 下载免费PDF全文
Jiaojiao Huang Chong‐Zhi Wang Xiaoli Gu Yankun Gao Hongjuan Zhang Shuhu Du Lina Chen Chun‐Su Yuan 《Biomedical chromatography : BMC》2016,30(2):117-125
A novel molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization with baicalein (BAI) as the template and used as solid‐phase extraction (SPE) adsorbent, aiming at the affinity isolation and selective knockout of BAI from Scutellaria baicalensis Georgi (SB). We used computational simulation to predict the optimal functional monomer, polymerization solvent and molar ratio of template to functional monomer. Characterization and performance tests revealed that MIP exhibited uniform spherical morphology, rapid binding kinetics, and higher adsorption capacity for BAI compared with nonimprinted polymer (NIP). The application of MIP in SPE coupled with high‐performance liquid chromatography to extract BAI from SB showed excellent recovery (94.3%) and purity (97.0%). Not only the single BAI compound, but also the BAI‐removed SB extract was obtained by one‐step process. This new method is useful for isolation and knockout of key bioactive compounds from herbal medicines. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
88.
Based on the governing equations of 2D plane-strain Biot’s consolidation, the relationship between generalized displacements and stresses of a single soil layer with anisotropic permeability and incompressible fluid and solid constituents is described by an analytical layer-element, which is deduced in the Laplace–Fourier transform domain by using the eigenvalue approach. Taking the boundary conditions and the continuity of the soil layers into consideration, a global stiffness matrix is subsequently assembled and solved. As to the 3D case, the same derivation is employed after the application of a decoupling transformation. The actual solutions in the physical domain can further be acquired by inverting the Laplace–Fourier transform. Finally, numerical examples are carried out to verify the presented theory and discuss the influence of the anisotropic permeability on the consolidation behavior. 相似文献
89.