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51.
Metal‐Catalyzed “On‐Demand” Production of Carbonyl Sulfide from Carbon Monoxide and Elemental Sulfur
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Wesley S. Farrell Peter Y. Zavalij Prof. Lawrence R. Sita 《Angewandte Chemie (International ed. in English)》2015,54(14):4269-4273
The group 6 molybdenum(II) cyclopentadienyl amidinate (CPAM) bis(carbonyl) complex [Cp*Mo{N(iPr)C(Ph)N(iPr)}(CO)2] (Cp*=η5‐C5Me5) serves as a precatalyst for the high‐yielding photocatalytic production of COS from CO and S8 under near‐ambient conditions (e.g., 10 psi, 25 °C). Further documented is the isolation and structural characterization of several key transition‐metal intermediates which collectively support a novel molybdenum(IV)‐based catalytic cycle as being operative. Finally, in the presence of an excess amount of a primary amine, it is demonstrated that this catalytic system can be successfully used for the “on‐demand” generation and utilization of COS as a chemical reagent for the synthesis of ureas. 相似文献
52.
This study proposes changes to the design and evaluation of the CO2 headspace test, which is used as a simple method for assessment of the complete biodegradability of surfactants. It presents a modified equation for the calculation of biodegradation. It is proposed that the solution of 7 mol L?1 sodium hydroxide commonly used in the process involving alkalinisation of the vial contents be replaced with 15 mol L?1 sodium hydroxide. The use of the higher hydroxide concentration leads to a significant reduction in the value of the blank CO2 headspace test. 相似文献
53.
M.?Jeyapriya B.?Meenarathi L.?Kannammal S.?Palanikumar R.?AnbarasanEmail author 《高分子科学》2015,33(10):1404-1420
The target of the present investigation is synthesis and characterization of an amphiphilic diblock copolymer with antibacterial property. Ring opening polymerization (ROP) of ε-caprolactone (CL) and tetrahydrofuran (THF) was carried out under inert atmosphere by using L-cysteine as a bridging agent in the presence of stannous octoate (SO) as a catalyst. The nano silver end capped diblock copolymer was synthesized by in situ method. Thus obtained nano silver end capped L-cysteine bridged diblock copolymer was characterized by various analytical methods like Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, circular dichroism (CD), fluorescence spectroscopy, gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM) and zeta potential. The antimicrobial property of the nano silver end capped diblock copolymer against e-coli was tested. 相似文献
54.
Plasma Chemistry and Plasma Processing - Two dielectric barrier discharge reactors, based on L-shaped electrodes, were designed and fabricated for in-line surface treatment of polyimide (PI)... 相似文献
55.
Kaur Jagjeet Dubey Vikas Parganiha Yogita Singh Deepti Suryanarayana N. S. 《Research on Chemical Intermediates》2015,41(6):3597-3621
Research on Chemical Intermediates - In this paper we review the luminescence properties of Pr3+-doped CaTiO3 phosphors, the different methods of sample preparation, and characterization of the... 相似文献
56.
Research on Chemical Intermediates - The electronic parameters of two azole molecules, namely benzoxazole (BOX) and benzothiazole (BTH), have been studied using DFT/B3LYP, MP2, and HF methods with... 相似文献
57.
Frontispiece: Combined Spectroscopic and Electrochemical Detection of a NiI⋅⋅⋅HN Bonding Interaction with Relevance to Electrocatalytic H2 Production
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58.
59.
Frontispiece: Surface Segregated AgAu Tadpole‐Shaped Nanoparticles Synthesized Via a Single Step Combined Galvanic and Citrate Reduction Reaction
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60.
Dr. Thomas Lunkenbein Dr. Frank Girgsdies Anna Wernbacher Dr. Johannes Noack Dr. Gudrun Auffermann Akira Yasuhara Achim Klein‐Hoffmann Prof. Wataru Ueda Dr. Maik Eichelbaum Dr. Annette Trunschke Prof. Robert Schlögl Dr. Marc G. Willinger 《Angewandte Chemie (International ed. in English)》2015,54(23):6828-6831
Complex Mo,V‐based mixed oxides that crystallize in the orthorhombic M1‐type structure are promising candidates for the selective oxidation of small alkanes. The oxygen sublattice of such a complex oxide has been studied by annular bright field scanning transmission electron microscopy. The recorded micrographs directly display the local distortion in the metal oxygen octahedra. From the degree of distortion we are able to draw conclusions on the distribution of oxidation states in the cation columns at different sites. The results are supported by X‐ray diffraction and electron paramagnetic resonance measurements that provide integral details about the crystal structure and spin coupling, respectively. 相似文献