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711.
Transmission electron microscopy was used to examine the dislocation structure of intermetallic Ti3Al subjected to deformation at tempertures T = 1073–1273 K. The microstructure of samples subjected to high-temperature deformation is established to contain mobile superdislocations of a and 2c + a types, and single dislocations with Burgers vector [0001] are also observed on the prismatic planes. Possible models of destruction of barriers associated with 2c + a superdislocations on the pyramidal planes are discussed using the results of computer simulations of the structure of a superdislocation core in in Ti3Al. 相似文献
712.
Abhijit Kar Gupta 《Physica A》2008,387(27):6819-6824
We examine the concept of relaxation in the wealth exchange models that are recently proposed in econophysics to interpret wealth distributions. To quantify and characterize the process of relaxation, we define an appropriate quantity and evaluate that numerically for the systems of many agents. Also, heuristic arguments are provided in support of some numerical results. 相似文献
713.
A Hybrid Anion for Ionic Liquid and Battery Electrolyte Applications: Half Triflamide,Half Carbonate
Kaitlyn E. Gunderson‐Briggs Thomas Rüther Adam S. Best Mega Kar Craig Forsyth Ekaterina I. Izgorodiana Douglas R. MacFarlane Anthony F. Hollenkamp 《Angewandte Chemie (International ed. in English)》2019,58(13):4390-4394
The synthesis of a new imide type anion, methylcarbonate(trifluoromethylsulfonyl)imide (MCTFSI) is described and the physicochemical properties of its sodium and N‐butyl‐N‐methyl pyrrolidinium salts as well as structural information obtained by X‐ray diffraction studies of the sodium salt are discussed in terms of charge delocalisation, coordination chemistry and electrochemical behaviour with respect to the analogous imdides bis(trifluoromethanesulfonyl)imide (TFSI) and bis(fluorosulfonyl)imide (FSI). The insight obtained from studying the new anion informs and reemphasizes the concept of weakly coordinating anions and coordination chemistry in designing electrolyte salts. 相似文献
714.
Marcelo H. Kravicz Debora T. Balogh Mrityunjoy Kar Stefanie Wedepohl Maria Vitoria L. B. Bentley Marcelo Caldern 《Macromolecular bioscience》2019,19(10)
The development of polymers with low toxicity and efficient gene delivery remains a significant barrier of nonviral gene therapy. Modification and tuning of chemical structures of carriers is an attractive strategy for efficient nucleic acid delivery. Here, polyplexes consisting of plasmid DNA (pDNA) and dodecylated or non‐dodecylated polysuccinimide (PSI)‐based polycations are designed, and their transfection ability into HeLa cells is investigated by green fluorescent protein (GFP) expressing cells quantification. All cationic polymers show lower cytotoxicity than those of branched polyethyleneimine (bPEI). PSI and bPEI‐based polyplexes have comparable physicochemical properties such as size and charge. Interestingly, a strong interaction between dodecylated polycations and pDNA caused by the hydrophobic moiety is observed in dodecylated PSI derivatives. Moreover, the decrease of GFP expression is associated with lower dissociation of pDNA from polyplexes according to the heparin displacement assay. Besides, a hydrophobization of PSI cationic derivatives with dodecyl side chains can modulate the integrity of polyplexes by hydrophobic interactions, increasing the binding between the polymer and the DNA. These results provide useful information for designing polyplexes with lower toxicity and greater stability and transfection performance. 相似文献
715.
716.
Nonlinear Dynamics - This paper proposes a singular perturbation-based approach to design saturated controllers for a class of nonlinear systems and shows its effectiveness in suppressing wing rock... 相似文献
717.
Ahmad Hadadpour Mehdi Jangi Kar Mun Pang Xue Song Bai 《Proceedings of the Combustion Institute》2019,37(4):4709-4716
The role of a split injection in the mixture formation and combustion characteristics of a diesel spray in an engine-like condition is investigated. We use large-eddy simulations with finite rate chemistry in order to identify the main controlling mechanism that can potentially improve the mixture quality and reduces the combustion emissions. It is shown that the primary effect of the split injection is the reduction of the mass of the fuel-rich region where soot precursors can form.Furthermore, we investigate the interaction between different injections and explain the effects of the first injection on the mixing and combustion of the second injection. Results show that the penetration of the second injection is faster than that of the first injection. More importantly, it is shown that the ignition delay time of the second injection is much shorter than that of the first injection. This is due to the residual effects of the ignition of the first injection which increases the local temperature and maintains a certain level of combustion some intermediates or radical which in turn boosts the ignition of the second injection. 相似文献
718.
Chikkamath Santosh S. Patil Dinesh M. Kabadagi Anand S. Tripathi Vaidehi S. Kar Aishwarya S. Manjanna Jayappa 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(3):1027-1034
Journal of Radioanalytical and Nuclear Chemistry - In this study, simple and a rapid solvent extraction method is investigated to recover Mo(VI) from simulated HLLW. The (NH4)6Mo7O24·4H2O... 相似文献
719.
Magdalena Gajda Łukasz Gajda Teobald Kupka Tapas Kar 《Magnetic resonance in chemistry : MRC》2020,58(2):145-153
Exponential dependencies between locally calculated geometric and magnetic indexes of aromaticity, harmonic oscillator model of aromaticity (HOMA) and nucleus independent chemical shifts (NICS)(0), NICS(1) and NICS(1)zz, and the number of conjugated benzene rings in linear acenes, from benzene to decacene were observed at B3LYP/6-311+G** level of theory. Correlations between HOMA and NICS indexes showed exponential dependencies and were fitted with simple three-parameter function. Similar correlations between both indexes of aromaticity and proton and carbon nuclear isotropic shieldings of individual acene rings were observed. Contrary to proton data, the predicted 13C nuclear isotropic shieldings of carbon atoms belonging to inner rings in polyacenes were less shielded, indicating lower aromaticity and therefore, higher reactivity. 相似文献
720.