Reaction Mechanism and Kinetics for HCCO Radical with NO

The mechanism and dynamical properties for the reaction of HCCO radicals with NO were investigated theoretically. The minimum energy paths(MEP) of the reaction were calculated by using the density functional theory(DFT) at the B3LYP/6-311+G ** level, and the energies along the MEP were further refined at the QCISD(T)/6-311+G ** level. It is found that the reaction mechanism of the title reaction involves three channels, producing HCNO+CO, HONC+CO and HCN+CO 2 products, respectively. Channel 1 is the most favorable path. The rate constant for channel 1 were calculated over a temperature range of 800—2500 K by using the canonical variational transition-state theory(CVT). The rate constant for the main path is negatively dependent on temperature, which is a characteristic of radical reactions with negative activation energy, and the variational effect for the rate constant calculation is small in the whole temperature range.

Synthesis of Barium Lithium Fluoride Nanocrystals Using Reverse Micelles as Microemulsion

Barium lithium fluoride nanocrystals were synthesized in cetyltrimethylammonium bromide (CTAB)/ 2-octanol/ water microemulsion systems. The impurity peaks in XRD patterns were not determined. The result of SEM confirmed that the average sizes and shape of the BaLiF3 nanocrystals. The formation of BaLiF3 and particles size were strongly affected by water content. With increasing water content and reaction times, the size of the particle increases. Meanwhile, the solvent was also found to play a key role in the synthesis of the BaLiF3 nanocrystals.

Synthesis and Characterization of A Small Molecule CFTR Chloride Channel Inhibitor

A thiazolidinone CFTR inhibitor(CFTR_ inh-172 ) was synthesized by a three-step procedure with trifluromethylaniline as the starting material. The synthesized CFTR inhibitor was characterized structurally by means of 1H NMR and functionally in a CFTR-expressing cell line FRT/hCFTR/EYFP-H148Q by both fluorescent and electrophysiological methods. A large amount(100 g) of high-quality small molecule thiazolidinone CFTR chloride channel inhibitor,CFTR_ inh-172 ,can be produced with this simple three-step synthetic procedure. The structure of the final product 2-thioxo-3-(3-trifluromethylphenyl)-5-[4-carboxyphenyl- methylene]-4-thiazolidinone was confirmed by 1H NMR. The overall yield was 58% with a purity over 99% as analyzed by HPLC. The synthesized CFTR_ inh-172 specifically inhibited CFTR chloride channel function in a cell-based fluorescence assay( K _d≈1.5 μmol/L) and in a Ussing chamber-based short-circuit current assay( K _d≈0.2 μmol/L),indicating better quality than that of the commercial combinatorial compound. The synthesized inhibitor is nontoxic to cultured cells at a high concentration and to mouse at a high dose. The synthetic procedure developed here can be used to produce a large amount of the high-quality CFTR_ inh-172 suitable for antidiarrheal studies and for creation of cystic fibrosis models in large animals. The procedure can be used to synthesize radiolabled CFTR_ inh-172 for in vivo pharmacokinetics studies.

Synthesis and Electronic Properties of 6-Chloro-2-diethylaminoethyl-3(2H)-pyridazinone

Chloro 2 diethylaminoethyl 3(2H) pyridazinone was synthesized by the reaction of 6 chloro 3(2H) pyridazinone and 2 diethylamionethyl chloride reaction in methylbenzene. Then the structure was characterized by means of 1H NMR, IR, UV. By the method of ab initio HF and density functional theory (DFT) B3LYP, the geometric structures of the reagent intermediate, the product and its isomer were optimized and their total energies were calculated. The properties for the frontier molecular orbitals and the rules for energy distribution were analyzed systematically. It was shown that the energy of the nitrogen alkyl compound is lower than that of the oxy alkyl compound and the former is stable than the latter . This result is in accordance with the fact that 6 chloro 2 diethylaminoethyl 3(2H) pyridazinone is synthesized by the reaction of \{6 chloride \}2 diethylaminoethyl 3(2H) pyridazinone and 2 diethylaminoethyl chloride.

Theoretical Studies on Electronic Spectrum Property of 2-(2-Hydroxyphenyl)pyridine Via Time-dependence Density Functional Theory Method

The geometrical structures of 2 (2 hydroxyphenyl) pyridine(PP) and its protonation states were optimized by means of the B3LYP/6 31G(d) method. For all the selected systems, the existence of H bond is in favor of the stability of the systems. On the basis of the optimized geometrical structures, their electronic spectrum properties were studied by time dependent density functional theory(TD DFT) methosd via a hybrid function of B3LYP and 6 31G(d) basis set. The TD DFT calculation result predicts the absorption spectrum of PP at 324 nm(3.82 eV), which is in very good agreement with the experimental value of 322 nm( 3.85 eV ) determined in solvent chloroform. The absorption spectra of the two protonation states both exert a red shift in various pH media.

Electrochemical Performance Studies of Tin Oxide Prepared by Sol-Gel

SnO\-2 prepared with the sol-gel technique at different temperatures was used as an anode material of the lithium-ion battery. We obtained the qualititave relationship between the electrochemical performance of tin oxide anode material and each of its carbon component, particle size, structure and surface morphology in detail. It was found that the best electrochemical performance can be reached by controlling the physical characteristics of SnO\-2, which was affected greatly by the treatment temperature. The SnO\-2 obtained at 600 ℃ was pure. When it was used as the anode material of the lithium-ion battery, it demonstrated a high initial specific capacity of 770 mA\5h/g.

Dispersion of Polyacenic Semiconductor(PAS) in Polyethylene: Molecular Dynamics Simulation

The dispersing process of polyacenic semiconductor(PAS) in polyethylene(PE) was simulated by using molecular dynamics(MD) methods. The results show that this process can be divided into three stages. In the first stage, PAS particles in the crystal region of PE are expelled to the amorphous region; in the second stage, PAS particles aggregate due to small surface areas and PE chains are adjusted continuously, which makes the crystal region complete; PAS particles are separated from each other and the total energy increases in the third stage. During the whole dispersing process, PAS particles are more stable in the amorphous region than in the crystal region. All the simulation results are in good agreement with the experimental results.

Electronic structures and nonlinear optical properties of XAuPH_3

The studies on model systems XAuPH3 (X=H, F, Cl, Br, I, CN, CH3 ) have been carried out by using ab intio HF and DFT B3LYP methods at pseudopotential and dou-ble-zeta LANL2DZ level. The results are compared with those of MP2. The properties of the models, i.e. the atomic net charge populations, the frontier molecular orbitals and nonlinear optical (NLO) properties have been investigated under an applied electric field on the basis of optimized structures. The computational results show that for these models characterized as electron acceptor-metal-electron donor (A-M-D) system, the NLO properties are due to in-tramolecular charge-transfer interaction between the accep-tor and the donor. The more charges transfer gives, the bet-ter NLO properties. In the selected model systems, IAuPH3 has the biggest bvec and g of 1184.1942 a.u. and 17341.9214 a.u., whereas IC6H4PH3+, a typical A--D organic conjugated system, has bvec and of 710.7697 and 11664.1405 a.u. respec-tively. In comparison, IAuPH3 has significant NLO proper-ties.