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71.
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   
72.
We report the fabrication and characterization of a magnetically recyclable Fe3O4@Nico@Ag catalyst for reduction reactions in the liquid phase. Fe3O4 is a magnetic core and nicotinic acid was used as the linker for Ag. The characterization was done with X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, vibrating sample magnetometry (VSM), and ultraviolet-visible spectroscopy. VSM measurements proved the super-paramagnetic property of the catalyst.  相似文献   
73.
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   
74.
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   
75.
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   
76.
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   
77.
Guo  L.  Zhang  S. T.  Lv  T. M.  Feng  W. J. 《Research on Chemical Intermediates》2015,41(6):3729-3742
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   
78.
A new mechanism of photosensitized formation of thymine (Thy) dimers is proposed, which involves generation of a delocalized triplet excited state as the key step. This is supported by chemical evidence obtained by combining one benzophenone and two Thy units with different degrees of freedom, whereby the photoreactivity is switched from a clean Paternò–Büchi reaction to a fully chemo‐, regio‐, and stereoselective [2+2] cycloaddition.  相似文献   
79.
Cancer treatment suffers from limitations that have a major impact on the patient’s quality of life and survival. In the case of chemotherapy, the systemic distribution of cytotoxic drugs reduces their efficacy and causes severe side effects due to nonselective toxicity. Photopharmacology allows a novel approach to address these problems because it employs external, local activation of chemotherapeutic agents by using light. The development of photoswitchable histone deacetylase (HDAC) inhibitors as potential antitumor agents is reported herein. Analogues of the clinically used chemotherapeutic agents vorinostat, panobinostat, and belinostat were designed with a photoswitchable azobenzene moiety incorporated into their structure. The most promising compound exhibits high inhibitory potency in the thermodynamically less stable cis form and a significantly lower activity for the trans form, both in terms of HDAC activity and proliferation of HeLa cells. This approach offers a clear prospect towards local photoactivation of HDAC inhibition to avoid severe side effects in chemotherapy.  相似文献   
80.
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