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991.
Journal of Structural Chemistry - Crystals of complex [Ph4Bi]2[(μ2-Br)Br3Ir(CH3CN)]2 (1) are prepared by the interaction of tetraphenylbismuth nitrate with sodium hexabromoiridate(IV) in water...  相似文献   
992.
Journal of Structural Chemistry - Perfect stoichiometric Pb5Ge3O11 single crystals are irradiated with 60Co γ-rays (1·106 Rad) and high-energy electrons (0.13 e/cm2, 0.89 e/cm2,...  相似文献   
993.
Moscow University Chemistry Bulletin - The complexation process of silver(I) ions with thiosemicarbazide (Tsc) in a wide range of concentrations of silver(I) and thiosemicarbazide at T =...  相似文献   
994.
Moscow University Chemistry Bulletin - The present study aimed to investigate use of density functional theory, noncovalent interactions and possible mechanisms of covalent functionalization of...  相似文献   
995.
Moscow University Chemistry Bulletin - A procedure is proposed for the kinetic determination of copper(II) by its catalytic effect on the reduction of iron(III) with thiosulfate ion, followed by...  相似文献   
996.
Theoretical and Experimental Chemistry - The latest research on photocatalytic systems based on graphite-like carbon nitride (g-C3N4) for decontamination of air pollutants, in particular, volatile...  相似文献   
997.
Without solvents present, the often far-from-equilibrium environment in a mechanochemically driven synthesis can generate high-energy, non-stoichiometric products not observed from the same ratio of reagents used in solution. Ball milling 2 equiv. K[A’] (A’=[1,3-(SiMe3)2C3H3]) with CaI2 yields a non-stoichiometric calciate, K[CaA’3], which initially forms a structure ( 1 ) likely containing a mixture of pi- and sigma-bound allyl ligands. Dissolved in arenes, the compound rearranges over the course of several days to a structure ( 2 ) with only η3-bound allyl ligands, and that can be crystallized as a coordination polymer. If dissolved in alkanes, however, the rearrangement of 1 to 2 occurs within minutes. The structures of 1 and 2 have been modeled with DFT calculations, and 2 initiates the anionic polymerization of methyl methacrylate and isoprene; for the latter, under the mildest conditions yet reported for a heavy Group 2 species (one-atm pressure and room temperature).  相似文献   
998.
Molecular doping of conjugated polymers (CPs) plays a vital role in optimizing organic electronic and energy applications. For the case of organic thermoelectrics, it is commonly believed that doping CPs with a strong dopant could result in higher conductivity (σ) and thus better power factor (PF). Herein, by investigating thermoelectric performance of a polar side-chain bearing CP, poly(3-(methoxyethoxyethoxy)thiophene) (P3MEET), vapor doped with fluorinated-derivative of tetracyanoquinodimethane FnTCNQ (n = 1, 2, 4), we show that using strong dopants can in fact have detrimental effects on the thermoelectric performance of CPs. Despite possessing higher electron affinity, doping P3MEET with F4TCNQ only results in a σ (27.0 S/cm) comparable to samples doped with other two weaker dopants F2TCNQ and F1TCNQ (26.4 and 20.1 S/cm). Interestingly, F4TCNQ-doped samples display a marked reduction in the Seebeck coefficient (α) compared to F1TCNQ- and F2TCNQ-doped samples from 42 to 13 μV/K, leading to an undesirable suppression of the PF. Structural characterizations coupled with Kang-Snyder modeling of the α–σ relation show that the reduction of α in F4TCNQ-doped P3MEET samples originates from the generation of low mobility carrier within P3MEET's amorphous domain. Our results demonstrate that factors such as dopant distribution and doping efficiency within the crystalline and amorphous domains of CPs should play a crucial role in advancing rational design for organic thermoelectrics.  相似文献   
999.
Research on Chemical Intermediates - In the present study, the synthesis of ligand 6-chloro-5-7-dimethyl-4oxo-4H-chromene-3-carbaldehydes by three steps from the substituted phenol. The formed...  相似文献   
1000.

A copper-based magnetic nanocatalyst has been prepared by co-precipitation method and characterized by FESEM, EDS, TEM, XRD, XRF, ICP–OES, FTIR, and BET analysis. This new nanocatalyst displays a good activity toward the aerobic oxidation of a wide range of alcohols in water. Moreover, it is recyclable up to five following runs by simple filtration without any significant loss of its catalytic activity.

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