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Kusum Bania Nilotpal Barooah Rupam Sarma Jubaraj Bikash Baruah 《Journal of chemical crystallography》2008,38(1):57-60
Abstract The crystal structure of a metallohybrid carboxylic acid obtained from the reaction of 1,3,5-benzenetricarboxylic acid (TCAH3)
with copper(II)acetate monohydrate in the presence of pyridine (py) having composition Cu(py)2(TCAH2)2(H2O)2 [1] is reported. It crystallizes in triclinic space group P-1 and with a = 7.0110(3)?, b = 8.9523(5)?, c = 11.5370(5) ?,
α = 79.776(3) °, β = 82.881(3)°, γ = 83.628(3)°, and V = 704.18(6)?3. The hydrogen bond in 1 is compared with the hydrogen bond pattern in the structure of 1,3-dicarbomethoxy 4,6-benzenedicarboxylic
acid, which crystallizes in mononclinic space group P21/c and has unit cell parameters of a = 6.9549(16)?, b = 8.7676(15)?,
c = 20.111(4)?; β = 92.585(17) ° and V = 1225.1(4) ?3.
Index Abstract Crystal structure of a metallohybrid carboxylic acid obtained from the reaction of 1,3,5-benzenetricarboxylic acid with copper(II)acetate
monohydrate in the presence of pyridine is determined and compared with hydrogen bond pattern present in the structure of
1,3-dicarbomethoxy 4,6-benzenedicarboxylic acid.
Crystal structure of a metallohybrid acid of 1,3,5-benzenetricarboxylic acid of copper(II).
Kusum Bania, Nilotpal Barooah, Rupam Sarma, Jubaraj B. Baruah 相似文献
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Weak transitions of decuplet isobars are expanded in terms of eigen-amplitudes of the direct channel in the framework of SU(3).
Starting with the most general weak Hamiltonian and assuming intermediate states to be non-exotic, we obtain ΔI=1/2 rule for Ω− decays. Invoking of the CP invariance forbids all thepv weak processesD(10)→D(10) +P(8). Decays of the charmed multiplets are also discussed in these dynamical considerations. We obtain triplet dominance of
charm changing weak Hamiltonian for Ω*++
3 decays. 相似文献
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Total synthesis of (+)-boronolide, (+)-deacetylboronolide, and (+)-dideacetylboronolide has been achieved from a single intermediate 26, which was synthesized in 11 steps from a d-mannitol-derived intermediate 8 in an overall yield of 10%. The key steps in the synthesis are inversion of a chiral center by taking an advantage of the inherent mechanism involved in the ring closing to an epoxide via intramolecular S(N)2 reaction and lactonization of a diol using Fetizons reagent. The strategy is amenable to preparation of analogues of (+)-boronolide in sufficient amount for further screening of biological activity. 相似文献
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Pawale Rajendra M. Shrikhande Mohan S. Rajbhar Kusum S. 《Designs, Codes and Cryptography》2022,90(4):871-879
Designs, Codes and Cryptography - Quasi-symmetric designs (QSDs) with particular block graphs are investigated. We rule out the possibility of a QSD with block graph that has the same parameters as... 相似文献
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The performance of PSO algorithm depends greatly on the appropriate parameter selection strategies for fine tuning its parameters. This paper proposes three new nonlinear strategies for selecting inertia weight which plays a significant role in particle’s foraging behaviour. The PSO variants implying these strategies are named as: fine grained inertia weight PSO (FGIWPSO); Double Exponential Self Adaptive IWPSO (DESIWPSO) and Double Exponential Dynamic IWPSO (DEDIWPSO). In FGIWPSO, inertia weight is obtained adaptively, depending on particle’s iteration wise performance and decreases exponentially. DESIWPSO and DEDIWPSO employ Gompertz function, a double exponential function for selecting inertia weight. In DESIWPSO the particles’ iteration wise performance is fed as input to the Gompertz function. On the other hand DEDIWPSO evaluates the inertia weight for whole swarm iteratively using Gompertz function where relative iteration is fed as input. The efficacy and efficiency of proposed approaches is validated on a suite of benchmark functions. The proposed variants are compared with non linear inertia weight and exponential inertia weight strategies. Experimental results assert that the proposed modifications help in improving PSO performance in terms of solution quality as well as convergence rate. 相似文献
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A molecularly imprinted polymer (MIP) able to selectively bind triclosan (TCS) and triclocarban (TCC), commonly used antibacterial agents in many consumer products, was prepared using noncovalent molecular imprinting methods. The prepared MIP was evaluated as a selective sorbent in SPE for sample cleanup before HPLC-UV analysis of TCS and TCC in soil and biosolid samples. The MIP was also compared with commercially available C18 SPE sorbent. The molecularly imprinted SPE (MISPE) developed in this study was more efficient than C18 SPE for the cleanup of extracts of soil and biosolid samples prior to the analysis of TCC and TCS using HPLC-UV. The LOQ values for both TCC and TCS in the soil samples were determined to be 40 microg/kg; in the biosolid samples, the LOQ values were 100 and 300 microg/kg for TCC and TCS, respectively. Compared to C18 SPE, using MISPE for sample cleanup may result in a significant reduction of analytical cost, because one MIP can be reused up to 35 times and HPLC-UV instead of HPLC/MS can be used for instrumental analysis following sample cleanup by MISPE. 相似文献
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[reaction: see text] Two simple TADDOL-derived monodentate ligands, the (1R,2S)-2-phenylcyclohexanol-derived phosphite and the N,N-(phenylbenzyl)phosphoramidite, give comparably high levels of enantioselectivity (90-96% ee) in the rhodium-catalyzed hydroborations of substituted styrenes bearing either electron-donating or electron-withdrawing substituents. Rhodium(I) chloride and tetrafluoroborate catalyst precursors give comparable results. Pinacolborane is superior to catecholborane in these reactions. 相似文献