نتایج جستجو برای: solid acid

تعداد نتایج: 921902  

Journal: :Recueil des Travaux Chimiques des Pays-Bas 1994

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه پیام نور - دانشگاه پیام نور استان تهران - دانشکده شیمی 1392

گیاهان juniperus excelsa m.beib. ,juniperus communis l. و juniperus sabina l. از گونه‎های دارویی با ارزش و معطر متعلق به جنس سروکوهی و راسته مخروطیان می‎باشند که در ارتفاعات رشته کوه البرز پراکندگی دارند. هدف از این پژوهش، شناسایی و مقایسه اجزای تشکیل دهنده اسانس میوه ها و سرشاخه‎های هوایی این گیاهان می‎باشد. در این تحقیق میوه‎ و سرشاخه‎های سه گونه فوق در مرداد سال 1390 از منطقه هزار جریب بهشهر...

Journal: :Journal of The Japan Petroleum Institute 1971

Journal: :Physical Review (Series I) 1907

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2014
ahmad shaabani nasim ganji mozhdeh seyyedhamzeh hamid mofakham

cellulose sulfuric acid as a bio-polymer based solid catalyst efficiently catalyzes the selectively oxidation of sulfides to sulfoxides and thiols to disulfides using hydrogen peroxide as a green oxidant with good yields at room temperature. the developed method offers a number of advantages such as high selectivity, mild reaction conditions, simple operation, cleaner reaction profiles, low cos...

Journal: :iranian journal of catalysis 2014
kobra nikoofar

ammonium monovanadate (nh4vo3) has been devoted as an efficient, commercially available, eco-friendly and reusable catalyst for the synthesis of bis(indolyl)methanes (bims), oxindole derivatives and also michael adducts of indoles at 50 °c under solvent-free conditions. the reusability of this solid acid catalyst in addition with its selectivity has also been examined.

Due to the decreasing production of nickel and cobalt from sulfide sources, the Ni and Co extraction from the oxide ores (laterites) have become more prevalent. In this research work, the effects of calcination prior to leaching, acid concentration, percent solid, pH, and stirring speed on the nickel and cobalt recoveries from an iron-rich laterite ore sample were investigated using diffe...

Journal: :Environmental science & technology 2007
J Karl C Nieman Richard C Holz Ronald C Sims

Cultures of the pyrene degrading Mycobacterium sp. KMS were incubated with [4-13C]pyrene or [4,5,9,10-14C]pyrene with and without a soil humic acid standard to characterize the chemical nature of the produced residues and evaluate the potential for bonding reactions with humic acid. Cultures were subjected to a "humic acid/ humin" separation at acidic pH, a duplicate separation followed by solv...

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