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51.
Kumar Gautam Mullick Prashansha Nandakumar Krishnadas Mutalik Srinivas Rao Chamallamudi Mallikarjuna 《Chromatographia》2022,85(7):629-642
Chromatographia - Stability-indicating reverse-phase HPLC analytical method for the quantification of Paclitaxel (PTX) in the bulk and cationic liposomes was developed. The optimized method was... 相似文献
52.
Chitra N. Chandrasekaran S. Srinivas C. Venkata Athmalingam S. Venkatraman B. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2461-2468
Journal of Radioanalytical and Nuclear Chemistry - In this study, the thoron diffusion characteristic in soil is used as a tool to measure the porosity of the soil. The feasibility is demonstrated... 相似文献
53.
Effect of Temperature and Discharge Rate on Electrochemical Performance of Fiber Nickel–Cadmium Cell
Senthilkumar M. Satyavani T. V. S. L. Raman M. Venkat Sahoo P. K. Kumar A. Srinivas 《Russian Journal of Electrochemistry》2022,58(1):43-49
Russian Journal of Electrochemistry - The effect of temperature and discharge rate on the discharge capacity of nickel–cadmium (Ni?Cd) cell is investigated quantitatively. Ni–Cd... 相似文献
54.
Vladislav S. Krasnoukhov Prof. Dr. Valeriy N. Azyazov Prof. Dr. Alexander M. Mebel Dr. Srinivas Doddipatla Dr. Zhenghai Yang Shane Goettl Prof. Dr. Ralf I. Kaiser 《Chemphyschem》2021,22(14):1497-1504
The chemical dynamics of the elementary reaction of ground state atomic silicon (Si; 3P) with germane (GeH4; X1A1) were unraveled in the gas phase under single collision condition at a collision energy of 11.8±0.3 kJ mol−1 exploiting the crossed molecular beams technique contemplated with electronic structure calculations. The reaction follows indirect scattering dynamics and is initiated through an initial barrierless insertion of the silicon atom into one of the four chemically equivalent germanium-hydrogen bonds forming a triplet collision complex (HSiGeH3; 3 i1 ). This intermediate underwent facile intersystem crossing (ISC) to the singlet surface (HSiGeH3; 1 i1 ). The latter isomerized via at least three hydrogen atom migrations involving exotic, hydrogen bridged reaction intermediates eventually leading to the H3SiGeH isomer i5 . This intermediate could undergo unimolecular decomposition yielding the dibridged butterfly-structured isomer 1 p1 (Si(μ-H2)Ge) plus molecular hydrogen through a tight exit transition state. Alternatively, up to two subsequent hydrogen shifts to i6 and i7 , followed by fragmentation of each of these intermediates, could also form 1 p1 (Si(μ-H2)Ge) along with molecular hydrogen. The overall non-adiabatic reaction dynamics provide evidence on the existence of exotic dinuclear hydrides of main group XIV elements, whose carbon analog structures do not exist. 相似文献
55.
We study superconducting systems in the regime where superconductivity is destroyed by phase fluctuations. We find that the Nernst effect has a much sharper temperature decay than predicted by Gaussian fluctuations, with an onset temperature that tracks Tc rather than the pairing temperature. We find a close quantitative connection with diamagnetism--the ratio of magnetization to transverse thermoelectric conductivity reaches a fixed value at high temperatures. We interpret measurements on underdoped cuprates in terms of a dilute vortex liquid over a wide temperature range above Tc. 相似文献
56.
We demonstrate that a flowing liquid jet can be controllably split into two separate subfilaments through the application of a sufficiently strong tangential stress to the surface of the jet. In contrast, normal stresses can never split a liquid jet. We apply these results to observations of uncontrolled splitting of jets in electric fields. The experimental realization of controllable jet splitting would provide an entirely novel route for producing small polymeric fibers. 相似文献
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59.
June Cyriac Justin Paulose Mathai George Marupaka Ramesh Ragampeta Srinivas Daryl Giblin Michael L. Gross 《Journal of the American Society for Mass Spectrometry》2014,25(3):398-409
ESI-protonated 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one (1) undergoes a gas-phase Nazarov cyclization and dissociates via expulsions of ketene and anisole. The dissociations of the [M + D]+ ions are accompanied by limited HD scrambling that supports the proposed cyclization. Solution cyclization of 1 was effected to yield the cyclic ketone, 2,3-bis-(2-methoxyphenyl)-cyclopent-2-ene-1-one, (2) on a time scale that is significantly shorter than the time for cyclization of dibenzalacetone. The dissociation characteristics of the ESI-generated [M + H]+ ion of the synthetic cyclic ketone closely resemble those of 1, suggesting that gas-phase and solution cyclization products are the same. Additional mechanistic studies by density functional theory (DFT) methods of the gas-phase reaction reveals that the initial cyclization is followed by two sequential 1,2-aryl migrations that account for the observed structure of the cyclic product in the gas phase and solution. Furthermore, the DFT calculations show that the methoxy group serves as a catalyst for the proton migrations necessary for both cyclization and fragmentation after aryl migration. An isomer formed by moving the 2-methoxy to the 4-position requires relatively higher collision energy for the elimination of anisole, as is consistent with DFT calculations. Replacement of the 2-methoxy group with an OH shows that the cyclization followed by aryl migration and elimination of phenol occurs from the [M + H]+ ion at low energy similar to that for 1. Figure
The role of methoxy group in the Nazarov cyclization of 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one in the gas-phase and condensed phase by June Cyriac, Justin Paulose, M. George, Department of Chemistry, Sacred Heart College, Thevara, Cochin, Kerala, India-682013., M. Ramesh, R. Srinivas, National center for Mass Spectrometry, IICT, Hyderabad, India. Daryl Giblin and Michael L. Gross, Department of Chemistry, Washington University in St.Louis, St.Louis, USA, MO 63130. 相似文献
60.
Bal Sydulu Singu Umashankar Male Palaniappan Srinivasan Srinivas Pabba 《Journal of Solid State Electrochemistry》2014,18(7):1995-2003
Polyaniline sulphate salt titanium dioxide composite (PANI-H2SO4·TiO2) was synthesized by chemical in situ polymerization of aniline in the presence of TiO2. The effect of anionic surfactant (sodium lauryl sulphate) in this reaction was also assessed. During the polymerization reaction, sodium lauryl sulphate (SLS) is converted to dodecyl hydrogen sulphate (DHS) in the presence of acidic medium and gets doped onto polyaniline along with sulphuric acid dopant, i.e. formation of polyaniline-sulphate-dodecyl hydrogen sulphate-titanium dioxide composite (PANI-H2SO4-DHS·TiO2). In the PANI-H2SO4-DHS·TiO2 composite, the presence of DHS is confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy-dispersive X-ray analysis (EDAX) and TiO2 is confirmed by XRD and EDAX results. In PANI-H2SO4-DHS·TiO2 system, the nanoparticle of TiO2 (10–20 nm) is uniformly embedded on nanofibres (20–60 nm) of PANI-H2SO4-DHS, and some part of PANI-H2SO4-DHS·TiO2 forms core–shell morphology, wherein TiO2 is in core and PANI-H2SO4-DHS in shell forms. Stability of PANI-H2SO4-DHS increases due to the incorporation of stable TiO2. Utility of PANI-TiO2 composite was carried out in supercapacitor cell system by performing cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopic techniques in 1 M H2SO4 solution. Very low values of solution resistance, charge transfer resistance and time constant are obtained between 0.2 and 0.6 V. Initial specific capacitance values for the cell carried out at low and high current densities are found to be 280 and 205 F g?1, respectively, and after 1,700 charge–discharge cycles, its retention in the specific capacitance values is found to be the same (65–66 %) with coulombic efficiency of 98–100 %. A capacitor can work even at a high discharge rate. The efficiency of oxidizing and doping power increases with the use of a surfactant. Moreover, the use of a long chain surfactant dopant containing polyaniline as an electrode material plays an important role to increase the performance of the supercapacitor by allowing the electrolyte to easily enter and come out from PANI electrodes. 相似文献