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991.
Chen NC Huang PY Lai CC Liu YH Wang Y Peng SM Chiu SH 《Chemical communications (Cambridge, England)》2007,(40):4122-4124
We describe a [2]rotaxane molecule that exhibits distinct signals in its (1)H NMR spectra upon the complexation of physiologically important Li(+), Na(+), Mg(2+) and Ca(2+) ions; thus, the identification of these metal ions in solution is possible from the analysis of a single (1)H NMR spectrum of a single molecular sensor. 相似文献
992.
Someswara Rao Kosuru Hsin‐Yu Lai Chien‐Yi Yang Gopal Chandru Senadi Yi‐Chun Lai Hsuan‐Ying Chen 《中国化学会会志》2019,66(1):110-113
The palladacycle complex [LsPdOAc]2 bearing 2‐phenyl benzothiazole was synthesized and characterized by NMR and X‐ray crystallography. [LsPdOAc]2 was used as a catalyst in the Suzuki–Miyaura cross coupling reaction of 4‐bromotoluene with phenylboronic acid, which resulted in a conversion of >90% with 5 mol% of the Pd complex within 10 min at 60°C. 相似文献
993.
Constructing reduced model for complex physical systems via interpolation and neural networks 下载免费PDF全文
The work studies model reduction method for nonlinear systems based on proper orthogonal decomposition (POD)and discrete empirical interpolation method (DEIM). Instead of using the classical DEIM to directly approximate thenonlinear term of a system, our approach extracts the main part of the nonlinear term with a linear approximation beforeapproximating the residual with the DEIM. We construct the linear term by Taylor series expansion and dynamic modedecomposition (DMD), respectively, so as to obtain a more accurate reconstruction of the nonlinear term. In addition, anovel error prediction model is devised for the POD-DEIM reduced systems by employing neural networks with the aid oferror data. The error model is cheaply computable and can be adopted as a remedy model to enhance the reduction accuracy.Finally, numerical experiments are performed on two nonlinear problems to show the performance of the proposed method. 相似文献
994.
Yang Chao Liu Xinjie Yang Kai Lai Yanqing Zhang Kai Tian Zhongliang 《Journal of Solid State Electrochemistry》2021,25(2):611-616
Journal of Solid State Electrochemistry - The effects of hydrogen evolution reaction on the deformation of zinc anode which cycles at nearly 100% depth of discharge (DOD) are studied. Results show... 相似文献
995.
A high efficiency and low toxicity radiosensitizer,OsN(PhenOH)Cl_3,was designed and synthesized through substituent regulation.To the best of our knowledge,this is the first osmium-based coordination complex radiosensitizer.The experimental results shown that this radiosensitizer induced G2/M cell cycle arrest mainly through induction of intracellular ROS overproduction. 相似文献
996.
Davide Palma Dimitra Papagiannaki Manuel Lai Rita Binetti Mohamad Sleiman Marco Minella Claire Richard 《Molecules (Basel, Switzerland)》2021,26(4)
Perfluoroalkyl substances (PFAS) represent one of the most recalcitrant class of compounds of emerging concern and their removal from water is a challenging goal. In this study, we investigated the removal efficiency of three selected PFAS from water, namely, perfluorooctanoic acid (PFOA), perfluorohexanoic acid (PFHxA) and pefluorooctanesulfonic acid (PFOS) using a custom-built non-thermal plasma generator. A modified full factorial design (with 2 levels, 3 variables and the central point in which both quadratic terms and interactions between couple of variables were considered) was used to investigate the effect of plasma discharge frequency, distance between the electrodes and water conductivity on treatment efficiency. Then, the plasma treatment running on optimized conditions was used to degrade PFAS at ppb level both individually and in mixture, in ultrapure and groundwater matrices. PFOS 1 ppb exhibited the best degradation reaching complete removal after 30 min of treatment in both water matrices (first order rate constant 0.107 min−1 in ultrapure water and 0.0633 min−1 in groundwater), while the degradation rate of PFOA and PFHxA was slower of around 65% and 83%, respectively. During plasma treatment, the production of reactive species in the liquid phase (hydroxyl radical, hydrogen peroxide) and in the gas phase (ozone, NOx) was investigated. Particular attention was dedicated to the nitrogen balance in solution where, following to NOx hydrolysis, total nitrogen (TN) was accumulated at the rate of up to 40 mgN L−1 h−1. 相似文献
997.
Credit risk analysis is an active research area in financial risk management and credit scoring is one of the key analytical techniques in credit risk evaluation. In this study, a novel intelligent-agent-based fuzzy group decision making (GDM) model is proposed as an effective multicriteria decision analysis (MCDA) tool for credit risk evaluation. In this proposed model, some artificial intelligent techniques, which are used as intelligent agents, are first used to analyze and evaluate the risk levels of credit applicants over a set of pre-defined criteria. Then these evaluation results, generated by different intelligent agents, are fuzzified into some fuzzy opinions on credit risk level of applicants. Finally, these fuzzification opinions are aggregated into a group consensus and meantime the fuzzy aggregated consensus is defuzzified into a crisp aggregated value to support final decision for decision-makers of credit-granting institutions. For illustration and verification purposes, a simple numerical example and three real-world credit application approval datasets are presented. 相似文献
998.
Lai Y 《Computational Biology and Chemistry》2006,30(5):321-326
It has been shown that the generalized F-statistics can give satisfactory performances in identifying differentially expressed genes with microarray data. However, for some complex diseases, it is still possible to identify a high proportion of false positives because of the modest differential expressions of disease related genes and the systematic noises of microarrays. The main purpose of this study is to develop statistical methods for Affymetrix microarray gene expression data so that the impact on false positives from non-expressed genes can be reduced. I proposed two novel generalized F-statistics for identifying differentially expressed genes and a novel approach for estimating adjusting factors. The proposed statistical methods systematically combine filtering of non-expressed genes and identification of differentially expressed genes. For comparison, the discussed statistical methods were applied to an experimental data set for a type 2 diabetes study. In both two- and three-sample analyses, the proposed statistics showed improvement on the control of false positives. 相似文献
999.
Kendra V. Sharp David Hill Daniel Troolin Geoffrey Walters Wing Lai 《Experiments in fluids》2010,48(1):167-183
Volumetric three-component velocimetry measurements have been taken of the flow field near a Rushton turbine in a stirred
tank reactor. This particular flow field is highly unsteady and three-dimensional, and is characterized by a strong radial
jet, large tank-scale ring vortices, and small-scale blade tip vortices. The experimental technique uses a single camera head
with three apertures to obtain approximately 15,000 three-dimensional vectors in a cubic volume. These velocity data offer
the most comprehensive view to date of this flow field, especially since they are acquired at three Reynolds numbers (15,000,
107,000, and 137,000). Mean velocity fields and turbulent kinetic energy quantities are calculated. The volumetric nature
of the data enables tip vortex identification, vortex trajectory analysis, and calculation of vortex strength. Three identification
methods for the vortices are compared based on: the calculation of circumferential vorticity; the calculation of local pressure
minima via an eigenvalue approach; and the calculation of swirling strength again via an eigenvalue approach. The use of two-dimensional
data and three-dimensional data is compared for vortex identification; a ‘swirl strength’ criterion is less sensitive to completeness
of the velocity gradient tensor and overall provides clearer identification of the tip vortices. The principal components
of the strain rate tensor are also calculated for one Reynolds number case as these measures of stretching and compression
have recently been associated with tip vortex characterization. Vortex trajectories and strength compare favorably with those
in the literature. No clear dependence of trajectory on Reynolds number is deduced. The visualization of tip vortices up to
140° past blade passage in the highest Reynolds number case is notable and has not previously been shown. 相似文献
1000.
Three new oleanane-type triterpenoid saponins, ilexhainanoside C, D and E, all with 24, 28-dioic acid groups, were isolated from the leaves of Ilex hainanensis. They were 3beta-hydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(1), 3beta, 19alpha-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(2) and 3beta, 29-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(3). The structures of these three new compounds were elucidated and complete assignments of the (1)H and (13)C NMR spectroscopic data were achieved by 1D and 2D NMR experiments [heteronuclear single quantum coherence (HSQC), HMBC and rotational nuclear Overhauser effect spectroscopy (ROESY)]. 相似文献