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991.
Research on Chemical Intermediates - In this work, a series of six organic dyes-sensitized solar cells (DSSCs) combining various π-bridges with a fixed donor (triphenylamine) and a fixed...  相似文献   
992.
We study the Glauber dynamics for the random cluster (FK) model on the torus with parameters (p,q), for q ∈ (1,4] and p the critical point pc. The dynamics is believed to undergo a critical slowdown, with its continuous‐time mixing time transitioning from for ppc to a power‐law in n at p = pc. This was verified at ppc by Blanca and Sinclair, whereas at the critical p = pc, with the exception of the special integer points q = 2,3,4 (where the model corresponds to the Ising/Potts models) the best‐known upper bound on mixing was exponential in n. Here we prove an upper bound of at p = pc for all q ∈ (1,4], where a key ingredient is bounding the number of nested long‐range crossings at criticality.  相似文献   
993.
Structural Chemistry - Comprehensive density functional theory calculations at B3LYP/6-311++G(d, p) level have been undertaken on a new type of organic Brønsted acids based on perchloric and...  相似文献   
994.
Meccanica - A Free Energy Lattice Boltzmann Method has been developed to characterize dominant forces and regimes involved in the capillary rise imbibition process. The comparison of the capillary...  相似文献   
995.
In this study, a step-by-step method for the synthesis of platinum nanoparticles and copper(I) complex supported on mesoporous silica hollow spheres (Pt-MSHSs-Cu) is introduced. Scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption–desorption, energy-dispersive X-ray spectrometry, X-ray photoelectron spectroscopy, and elemental and thermogravimetric analyses were applied for characterization of the surface, structure, size, phase composition, and morphology of the synthesized materials. The characterized material, Pt-MSHSs-Cu, was used as an efficient and heterogeneous catalyst in the Sonogashira coupling reaction under different reaction conditions. In comparison with MSHSs, Cu(I)-functionalized MSHSs (MSHSs-Cu), and Pt-MSHSs samples, the Pt-MSHSs-Cu catalyst exhibited significantly increased catalytic performance with 91.50% yield. Therefore, the results obtained suggested a synergistic effect derived from platinum nanoparticles, MSHSs substrate, and copper(I) complex, which enhanced the rate of the Sonogashira coupling reaction.  相似文献   
996.
Russian Journal of General Chemistry - The multi-component reaction of diacetyl triazole derivative with ethyl cyanoacetate and various aromatic aldehydes according to the conventional and solvent...  相似文献   
997.
Catalysis Surveys from Asia - An acid gas stream was utilized instead of pure H2S as feedstock in the methanol thiolation reaction with Alkali/W/γ-Al2O3 catalysts. The catalysts were...  相似文献   
998.
To produce a novel class of anticancer compounds, an efficient method for synthesizing novel β-lactone and β-lactam frameworks was developed based on the reaction of a new ketene with C=O and C=N bonds. Functionalized 2-azetidinones were efficiently synthesized by employing 2,4-dichlorophenoxylketene, which was generated in situ. The reaction of the ketene with aldehydes was not successful and in all cases except for 4-nitrobenzaldehyde, a rearranged dimer of the ketene was obtained as a lactone. Anticancer cellular activity of all new β-lactams and lactones on breast cancer cells was studied. All new synthesized compounds exhibited potential anticancer activity which may guarantee their future application in moderate chemotherapy.  相似文献   
999.
Structural Chemistry - In a continuing effort to find new cytotoxic, antitumor, and less toxic agents from β-carbolines derivatives, using experimental and computational studies, five...  相似文献   
1000.
Journal of Thermal Analysis and Calorimetry - One of the important parameters in developing dry ice blasting nozzle is the high-speed dry ice pellets. However, many studies focus primarily only on...  相似文献   
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