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991.
Sukri Mohd Farid Fahmi Khavarian Mehrnoush Mohamed Abdul Rahman 《Research on Chemical Intermediates》2018,44(4):2585-2605
Research on Chemical Intermediates - Carbon dioxide reforming of methane was studied over Co/MgO catalyst which was prepared by using the direct sol–gel method with different Co loadings. The... 相似文献
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The water soluble catalytic system comprising of CuCl2 and 2,2-biquinoline-4,4-dicarboxylic acid dipotassium salt(BQC) is highly efficient organic metallic catalysts for selective oxidation of benzyiic and alicyciic compounds to the corresponding ketones, ex:indan to indanone,ethyl benzene to acetophenone. 相似文献
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E. Ramakrishna Kapil Dev Saransh Wales Maurya Ibadur Rahman Siddiqui Rakesh Maurya 《Tetrahedron letters》2017,58(6):570-573
We have developed a novel and efficient method for the oxidation of aryl sulfonylhydrazones to N-aroyl-N′-acyl arylsulfonylhydrazides, using hypervalent iodine (III) reagent in good yields at room temperature. 相似文献
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Residue level and dissipation pattern of lepimectin in shallots using high‐performance liquid chromatography coupled with photodiode array detection 下载免费PDF全文
Sung‐Woo Kim Md. Musfiqur Rahman A. M. Abd El‐Aty Lieu T. B. Truong Jeong‐Heui Choi Joon‐Seong Park Mi‐Ra Kim Ho‐Chul Shin Jae‐Han Shim 《Biomedical chromatography : BMC》2016,30(11):1835-1842
Lepimectin, as an emulsifiable concentrate, was sprayed on shallots at the recommended dose rate (10 mL/20 L) to determine its residue levels, dissipation pattern, pre‐harvest residue limits (PHRLs), and health risk. Samples were randomly collected over 10 days, extracted with acetonitrile, purified using an amino solid‐phase extraction (NH2‐SPE) cartridge and analyzed using a high‐performance liquid chromatography–photodiode array detection method. Field‐incurred samples were confirmed using ultra‐performance liquid chromatography–tandem mass spectrometry. The linearity was excellent, with a determination coefficient (R2) of ≥0.9991. The recoveries at two spiking levels (0.2 and 1.0 mg/kg) ranged from 84.49 to 87.64% with relative standard deviations of ≤7.04%. The developed method was applied to field samples grown in separate greenhouses, one located in Naju and one in Muan, in the Republic of Korea. The dissipation pattern was described by first‐order kinetics with half‐lives of 1.9 (Naju) and 1.7 days (Muan). The PHRL curves indicated that, if the lepimectin residues are <0.18 (Naju) and <0.13 mg/kg (Muan) 5 days before harvest, the residue levels will be lower than the maximum residue limit (0.05 mg/kg) upon harvesting. The risk assessment data indicated that lepimectin is safe for use in the cultivation of shallots, with no risk of detrimental effects to the consumer. 相似文献
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The variation of electrical resistivity in the system of glasses Ge17Te83?xTlx, with (1≤x≤13), has been studied as a function of high pressure for pressures up to 10 GPa. It is found that the normalized electrical resistivity decreases continuously with the increase in pressure and shows a sudden drop at a particular pressure (transition pressure), indicating the presence of a transition from semiconductor to near-metallic at these pressures which are in the range 3.0–5.0 GPa. This transition pressure is seen to decrease with the increase in the percentage content of thallium due to increasing metallicity of the thallium. The transition is reversible under application of pressure and X-ray diffraction of samples recovered after pressurization show that they remain amorphous after undergoing a pressurization decompression cycle. 相似文献