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151.
Pavel Arsenyan Irina Shestakova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2427-2430
The cytotoxic activity of a series of methylammonium tellurates on human fibrosarcoma HT-1080, mouse hepatoma MG-22A, and mouse fibroblasts 3T3 cell lines is described. The role of tellurates as free radical regulators is discussed. 相似文献
152.
Chen Ru-yu Cheng Leifeng 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):193-195
Abstract Cyclization of 1 with 2 yielded the title compound 3, which was transformed into the corresponding 1,3,2,4-diazadiphospholanes 4 and 5 by using DMSO or sulfur respectively. The addition reaction of 3 with butanedione gave 3,4-di-oxo-1-phenyl-2,5-diaza-6,9-dioxa-1λ5,3λ4-diphosphaspiro[4,4]nonane 6. The structures of 3, 4 and 5 were confirmed by elemental analysis, IR, NMR and GC-MS. Although 6 could not be isolated in pure form because of its rapid decomposition, the 31P NMR data indicated its existence. It was found that there were cis- and trans-isomers in 3, 4, 5 and 6. 相似文献
153.
This report describes development of an in silico, expert rule-based method for the classification of chemicals into irritants or non-irritants to eye, as defined by the Draize test. This method was developed to screen data-poor cosmetic ingredient chemicals for eye irritancy potential, which is based upon exclusion rules of five physicochemical properties – molecular weight (MW), hydrophobicity (log P), number of hydrogen bond donors (HBD), number of hydrogen bond acceptors (HBA) and polarizability (Pol). These rules were developed using the ADMET Predictor software and a dataset of 917 eye irritant chemicals. The dataset was divided into 826 (90%) chemicals used for training set and 91 (10%) chemicals used for external validation set (every 10th chemical sorted by molecular weight). The sensitivity of these rules for the training and validation sets was 72.3% and 71.4%, respectively. These rules were also validated for their specificity using an external validation set of 2011 non-irritant chemicals to the eye. The specificity for this validation set was revealed as 77.3%. This method facilitates rapid screening and prioritization of data poor chemicals that are unlikely to be tested for eye irritancy in the Draize test. 相似文献
154.
155.
Nonstationarity and related measures for time‐dependent hartree–fock and multiconfigurational models
Anatoliy V. Luzanov 《International journal of quantum chemistry》2013,113(23):2489-2505
Based on an earlier article (Eberly and Singh, Phys. Rev. D 1973 , 7, 359) and related works on short‐time evolution, this article proposes a many‐electron formulation for the nonstationarity degree which can be assigned to quantum system at each time point. The key measure introduced, , is a nonstationarity index that can be thought of as an inverse nominal lifetime at each instance of time. The index is directly computed from the time derivative of one‐electron density matrix and is a size‐consistent quantity. In this article, the approach is developed for the time‐dependent Hartree–Fock (TDHF), single‐excitation (TDCIS), and time‐dependent full configuration interaction (TDFCI) models. As a rule, nonstationarity effects are more pronounced in correlated electron systems, and a joint analysis of and the multiconfigurational character of wave functions apparently provide a deeper insight into dynamical molecular processes. The performed calculations on small molecules in laser fields show a preference for the TDCIS model when comparing TDCIS and TDHF with the “exact” TDFCI model. © 2013 Wiley Periodicals, Inc. 相似文献
156.
Micro‐RNAs (miRNAs) are small, endogenous, singlestranded, and noncoding RNAs. The miRNAs have been found to perform important functions in many cellular processes, such as development, proliferation, differentiation, and apoptosis. Circulating miRNAs have been proposed as emerging biomarkers in diseases such as cancer, diabetes, and cardiovascular disease including acute myocardial infarction (AMI). In this study, we developed CE with LIF (CE‐LIF) using fluorescence‐labeled DNA probe for determination of low abundance miRNA in cell extracts. The target miRNA is miRNA‐499, a biomarker candidate of AMI with low abundance in biological samples. In order to measure the trace level of miRNA, we optimized the hybridization conditions such as hybridization time, temperature, and buffer solution. The highest fluorescence intensity of the hybridized miRNA‐499 was found when hybridization was conducted at 40°C in 50 mM Tris‐acetate (pH 8.0) buffer containing 50 mM NaCl, and 10 mM EDTA for 15 min. The hybridized miRNA‐499 was detected in cultured H9c2 cardiomyoblast cells and the analysis of miRNA‐499 was completed within 1 h using CE‐LIF. These results showed the potential of CE for fast, specific, and sensitive high‐throughput analysis of low‐abundance miRNAs in cell extracts, biofluids, and tissues. 相似文献
157.
The initial value problem for creeping flow of the upper convected Maxwell fluid at high Weissenberg number 下载免费PDF全文
Michael Renardy 《Mathematical Methods in the Applied Sciences》2015,38(5):959-965
We consider the equations for time dependent creeping flow of an upper convected Maxwell fluid. For finite Weissenberg number, these equations can be reformulated as a coupled system of a hyperbolic equation for the stresses and an elliptic equation for the velocity. In the high Weissenberg number limit, however, the elliptic equation becomes degenerate. As a consequence, the initial value problem is no longer uniquely solvable if we just naively let the Weissenberg number go to infinity in the equations. In this paper, we make an a priori assumption on the stresses, which is motivated by the behavior in shear flow. We formulate a systematic perturbation procedure to solve the resulting initial value problem. Copyright © 2014 JohnWiley & Sons, Ltd. 相似文献
158.
The present work describes the synthesis, characterization and application of functionalized surfactants derived through simple organic reaction steps. These surfactants have been particularly tailor made to resist hardness due to calcium ions in water. It is unique of its kind because here the surfactants have an analogous hydrophobic chain but differ structurally in the composition of the head groups in terms of the position of attachment of the chain. The effect of this small variability in the head group on the surfactant property, adsorption, self assembly and calcium tolerance behaviour has been studied in detail. This kind of phenol–keto surfactants has not been reported before. It was also found that one of the surfactants was more tolerant towards Ca2+ ion than the other. The individual packing behaviour of the surfactants at the air–water interface has been projected to cause this difference which is very interesting. 相似文献
159.
《Arabian Journal of Chemistry》2014,7(6):955-963
A series of 3-diphenylmethyl-6-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (4a–j and 5a–d) were synthesized by condensation of 4-amino-5-diphenylmethyl-4H-1,2,4-triazole-3-thiol with various substituted aromatic acids and aryl/alkyl-isothiocyanates. The structures of synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and mass spectroscopic studies. These compounds were tested in vivo for their anti-inflammatory activity. The compounds which showed activity comparable to the standard drug ibuprofen were screened for their analgesic, ulcerogenic, lipid peroxidation and hepatotoxic effects. Compounds 6-(4-chlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole (4a) and 6-(2,4-dichlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole(4c) emerged as the most active compounds of the series and were moderately more potent than the standard drug ibuprofen. 相似文献
160.
In the current research, through employing the dual ligand method, a novel coordination polymer has been produced in success via the reaction between H2glu and In(NO3)3·6H2O in the existence of the nitrogen-donor chelating 2,2′-bpy ligand in CH3CN In(III) and DMF mixed solvent, and its chemical formula is In(glu)(Hglu)(2,2′-bpy) (1, 2,2′-bpy is 2,2′-bipyridine and H2glu is glutaric acid). Its application values on the acute stroke were assessed and the corresponding mechanism was investigated simultaneously. Firstly, the levels of inflammatory response in the astrocytes were evaluated by ELISA by measuring the content of inflammatory cytokines released into cerebrospinal fluid. Additionally, the miRNA199a relative expression levels in astrocytes were measured via exploiting real time RT-PCR. Molecular docking simulation demonstrated that synthesized In ion complex exhibited excellent biological activities, multiple binding interactions were formed by the carboxyl groups on the In ion complex. 相似文献