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61.
Thermal characterization of NaNO3/KNO3 with different concentrations of Al2O3 and TiO2 nanoparticles
Raja Jeyaseelan T. Azhagesan N. Pethurajan Vignesh 《Journal of Thermal Analysis and Calorimetry》2019,136(1):235-242
Journal of Thermal Analysis and Calorimetry - The thermo-physical properties of NaNO3/KNO3 (solar salt) added with Al2O3 and TiO2 nanoparticles as phase change material in thermal energy storage... 相似文献
62.
Eswaran Chinnaraja Rajendran Arunachalam Jayanta Samanta Ramalingam Natarajan Palani S. Subramanian 《应用有机金属化学》2019,33(5)
The one‐pot metal templated synthesis of enantiopure binuclear Zn (II) complexes Zn2L1–Zn2L4 were obtained by treating (1R,2R)‐diphenylethylenediamine or (1S,2S)‐diphenylethylenediamine with 2‐hydroxy‐5‐methyl‐1,3‐benzenedicarboxaldehyde or 4‐tert‐butyl‐2,6‐diformylphenol and zinc acetate. The chiroptical properties of the complexes were studied by using circular dichroism spectroscopy. These ΔΔ and ΛΛ complexes were used as enantioselective catalysts for desymmetrization of meso diol to achieve monobenzoylated product with 96% yield and 88% ee. 相似文献
63.
An eco-friendly and a simple ipso-nitration protocol for a series of aliphatic and (hetero)aromatic carboxylic acids using nitronium tetrafluoroborate, 1-hexyl-3,4,5-trimethyl-1H-imidazolium tetrafluoroborate and base is reported. While contrasted with recently known decarboxylative ipso-nitration strategies for the preparation of nitro compounds, this protocol does not require a toxic metal catalyst and harmful volatile organic solvents. Moreover, this method is perfect for a broad range of functional groups and affords exclusively the ipso-nitrated product in moderate to good yields. 相似文献
64.
G. Palani E. J. Lalith Kumar K.-Y. Kim 《Journal of Applied Mechanics and Technical Physics》2016,57(3):473-482
The present paper deals with a flow of a viscous incompressible fluid along a heated vertical cone, with due allowance for variations of viscosity and thermal diffusivity with temperature. The fluid viscosity is assumed to be an exponential function of temperature, and the thermal diffusivity is assumed to be a linear function of temperature. The governing equations for laminar free convection of the fluid are transformed into dimensionless partial differential equations, which are solved by a finite difference method with the Crank–Nicolson implicit scheme. Dependences of the flow parameters on the fluid viscosity and thermal conductivity are obtained. 相似文献
65.
Chunhui Huang Cannon B. Wille Huaibing He Vijay Bhasker Gangula Reddy Ravi P. Nargund Songnian Lin Anandan Palani 《Tetrahedron letters》2017,58(12):1219-1222
The late-stage modification of native peptides to alter and/or enhance their properties and functions is attractive but formidably challenging. Peptide lipidation is one of the effective strategies to overcome short half-life and rapid clearance. Herein, we report a late-stage installation of a fatty acid lipid onto fully elaborated peptides, using glucagon as an example, through regio- and chemoselective functionalization of tryptophan with high potency and remarkable in vivo half-life extension. 相似文献
66.
Xin-E Duan Bo Yuan Rui Li Arumugam Vignesh Chantsalnyam Bariashir Zilong Li Sheng-Di Bai Yanping Ma Jian-Bin Chao Hong-Bo Tong Wen-Hua Sun 《应用有机金属化学》2020,34(5):e5586
Mononuclear zirconium complex 3a of the molecular identity [Zr[η2-(C4H3O)C (Et) = NNPh]Cl3(THF)2], dinuclear zirconium complexes 3b [{Zr[η2-(C4H3O)C(i-Pr) = NNPh]2}2(μ2-Cl)3(μ3-Cl)2Li(Et2O)] and 3c [{Zr[η2-(C4H3O)C(t-Bu) = NNPh]2}2Cl2(μ2-Cl)2] have been synthesized by the treatment of lithium salt of (C4H3O)C(R) = NNHPh (R = CH3CH2, 1a ; R = (CH3)2CH, 1b ; R = (CH3)3C, 1c ), with different molar ratios of anhydrous zirconium tetrachloride. Of these, complex 3b was formed with lithium adduct and no such adduct was found in complex 3c . Compound 1a and all the zirconium complexes ( 3a - 3c ) were structurally characterized by single-crystal X-ray diffraction studies. Thus, it revealed that each hydrazonato ligand acts in a strained η2-coordination fashion for the three zirconium complexes. The molecular structures of the three zirconium complexes ( 3a - 3c ) reveal the existence of intramolecular hydrogen bonding interactions. Interestingly, complexes 3a and 3b assemble into a two-dimensional network structure through intermolecular hydrogen-bonding interactions. Upon activation with methylaluminoxane (MAO), all the complexes namely 3a , 3b , and 3c exhibited moderate catalytic activities toward ethylene polymerization and produced high molecular weight polyethylene with narrow molecular weight distributions. 相似文献
67.
Slow Magnetic Relaxation and Single‐Molecule Toroidal Behaviour in a Family of Heptanuclear {CrIIILnIII6} (Ln=Tb,Ho, Er) Complexes 下载免费PDF全文
Dr. Kuduva R. Vignesh Dr. Stuart K. Langley Abinash Swain Dr. Boujemaa Moubaraki Dr. Marko Damjanović Prof. Wolfgang Wernsdorfer Prof. Gopalan Rajaraman Prof. Keith S. Murray 《Angewandte Chemie (International ed. in English)》2018,57(3):779-784
The synthesis, magnetic properties, and theoretical studies of three heterometallic {CrIIILnIII6} (Ln=Tb, Ho, Er) complexes, each containing a metal topology consisting of two Ln3 triangles connected via a CrIII linker, are reported. The {CrTb6} and {CrEr6} analogues display slow relaxation of magnetization in a 3000 Oe static magnetic field. Single‐crystal measurements reveal opening up of the hysteresis loop for {CrTb6} and {CrHo6} molecules at low temperatures. Ab initio calculations predict toroidal magnetic moments in the two Ln3 triangles, which are found to couple, stabilizing a con‐rotating ferrotoroidal ground state in Tb and Ho examples and extend the possibility of observing toroidal behaviour in non DyIII complexes for the first time. 相似文献
68.
Kuppan Saravanan Jagadese J. Vittal M. V. Reddy B. V. R. Chowdari Palani Balaya 《Journal of Solid State Electrochemistry》2010,14(10):1755-1760
Although LiFePO4 (LFP) is considered to be a potential cathode material for the lithium-ion batteries, its rate performance is significantly restricted by sluggish kinetics of electrons and lithium ions. Several attempts have been made so far to improve the performance of LiFePO4 by reducing the grain size, doping with aliovalent atoms, and coating conductive materials such as carbon or RuO2. We report here synthesis of LFP nanoplates by solvothermal method, tailoring the thickness as well as carbon coverage at surfaces to explore their influence on the storage performance. Due to the fact that Li+ ion diffuses along the b-axis, solvothermal method was aimed to control the thickness of nanoplates across the b-axis. We synthesized several nanoplates with various plate thicknesses along b-axis; among those, nanoplates of LFP with ~30-nm-thick b-axis having thin (2–5 nm) and uniform layer of carbon coating exhibits high storage capacity as well as high rate performances. Thus, a favorable morphology for LiFePO4 has been achieved via solvothermal method for fast insertion/extraction of Li+ as compared to spherical nanoparticles of carbon-coated LFP. Galvanostatic cycling shows a capacity of 164?±?5 mAh g?1 at 0.1 C rate, 100?±?5 mAh g?1 at 10 C rate, and 46?±?5 mAh g?1 at 30 C rate, with excellent capacity retention of up to 50 cycles. Further attempts have been made to synthesize LiMnPO4 (LMP) as well as Li(Fe1???x Mn x )PO4/C (x?=?0.5) nanoplates using solvothermal method. Although LiMnPO4 does not exhibit high storage behavior comparable with that of LiFePO4, the mixed systems have shown an impressive storage performance. 相似文献
69.
Large Hexadecametallic {MnIII–LnIII} Wheels: Synthesis,Structural, Magnetic,and Theoretical Characterization 下载免费PDF全文
Kuduva R. Vignesh Dr. Stuart K. Langley Dr. Boujemaa Moubaraki Prof. Keith S. Murray Prof. Gopalan Rajaraman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16364-16369
The synthesis, gas sorption studies, magnetic properties, and theoretical studies of new molecular wheels of core type {MnIII8LnIII8} (Ln=Dy, Ho, Er, Y and Yb), using the ligand mdeaH2, in the presence of ortho‐toluic or benzoic acid are reported. From the seven wheels studied the {Mn8Dy8} and {Mn8Y8} analogues exhibit SMM behavior as determined from ac susceptibility experiments in a zero static magnetic field. From DFT calculations a S=16 ground state was determined for the {Mn8Y8} complex due to weak ferromagnetic MnIII–MnIII interactions. Ab initio CASSCF+RASSI‐SO calculations on the {Mn8Dy8} wheel estimated the MnIII–DyIII exchange interaction as ?0.1 cm?1. This weak exchange along with unfavorable single‐ion anisotropy of DyIII/MnIII ions, however, led to the observation of SMM behavior with fast magnetic relaxation. The orientation of the g‐anisotropy of the DyIII ions is found to be perpendicular to the plane of the wheel and this suggests the possibility of toroidal magnetic moments in the cluster. The {Mn8Ln8} clusters reported here are the largest heterometallic MnIIILnIII wheels and the largest {3d–4f} wheels to exhibit SMM behavior reported to date. 相似文献
70.
Chandrasekhar V Sasikumar P Boomishankar R 《Dalton transactions (Cambridge, England : 2003)》2008,(38):5189-5196
The reaction of ArPO(3)H(2) (Ar = 2,4,6-iPr(3)-C(6)H(2)) with Cd(CH(3)COO)(2).2H(2)O using various co-ligands such as methanol, dimethylformamide (DMF) and 3,5-dimethylpyrazole (DMPZH) resulted in the formation of tetranuclear assemblies [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(CH(3)OH)(4)].3(CH(3)OH) (1), [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(DMF)(4)].3(DMF) (2) and [Cd(4)(ArPO(3))(2)(ArPO(3)H)(4)(DMF)(2)(DMPZH)(2)].2(DMF).2(H(2)O) (3). In all of these compounds the tetranuclear cadmium array, containing two five-coordinate and two six-coordinate cadmium atoms, is held together by two mu(4) capping [ArPO(3)](2-) and four anisobidentate mu(2) [ArPO(2)(OH)](-) ligands. Each cadmium atom is bound to an additional ancillary ligand. The reaction of ArPO(3)H(2) with Cd(CH(3)COO)(2).2H(2)O in the presence of the chelating ligand 2,2'-bipyridine (bipy) leads to the exclusive formation of the dinuclear assembly [Cd(2)(ArPO(3)H)(4)(bipy)(2)].(CH(3)OH)(H(2)O) (4). The latter contains an eight-membered Cd(2)P(2)O(4) inorganic ring formed as a result of the bridging coordination action of two anisobidentate mu(2) [ArPO(2)(OH)](-) ligands. Each cadmium atom is bound by one chelating bipy and one monodentate [ArPO(2)(OH)](-) ligands. Use of four equivalents of 3,5-dimethylpyrazole leads to the formation of the mononuclear derivative [Cd(ArPO(3)H)(2)(DMPZH)(4)] (5). The molecular structure of the latter comprises of a central cadmium atom surrounded by six monodentate ligands. Four of these are neutral pyrazole ligands that occupy the equatorial plane; the remaining two are anionic phosphinate ligands which are present trans to each other. The thermal analysis of 1 and 4 reveals that the char residue obtained at 600 degrees C consists predominantly of Cd(2)P(2)O(7). 相似文献