نتایج جستجو برای: acid base catalyst

تعداد نتایج: 1012226  

Journal: :The Journal of biological chemistry 2010
Silke Litzinger Stefanie Fischer Patrick Polzer Kay Diederichs Wolfram Welte Christoph Mayer

Three-dimensional structures of NagZ of Bacillus subtilis, the first structures of a two-domain β-N-acetylglucosaminidase of family 3 of glycosidases, were determined with and without the transition state mimicking inhibitor PUGNAc bound to the active site, at 1.84- and 1.40-Å resolution, respectively. The structures together with kinetic analyses of mutants revealed an Asp-His dyad involved in...

Journal: :journal of nanostructures 2015
h. khojasteh v. mirkhani m. moghadam s. tangestaninejad i. mohammadpoor-baltork

palladium is the best metal catalyst for suzuki cross coupling reaction for synthesize of unsymmetrical biaryl compounds. but its high cost limits its application in wide scale. using of nanoscale particles as active catalytic cites is a good approach for reducing needed noble metal. by loading precious nanoparticles on magnetic nanocores as a support, recycling and reusing of catalyst will be ...

Journal: :iranian journal of catalysis 2011
roozbeh javad kalbasi zohreh s. shahzeidi farzad zamani

a simple and green synthetic strategy to prepare bao/tio2-zro2 as a solid base catalyst was reported. these materials with various amounts of bao were prepared by the adsorption method. the physical and chemical properties of bao/tio2-zro2 were investigated by x-ray diffraction, x-ray fluorescence, specific surface area and bjh pore size distribution, ft-ir spectroscopy, scanning electron micro...

2009
Shuli Yan Steven O. Salley K. Y. Simon Ng

A single-step method was developed for biodiesel production from unrefined or waste oils using a series of heterogeneous zinc and lanthanum mixed oxides. Effects of metal oxide molar ratio, free fatty acids (FFA) and water content in feedstock, molar ratio of methanol and oil, and reaction temperature on the yield of biodiesel were investigated. A strong interaction between Zn and La species wa...

2015
Lin Zhong Chokkalingam Anand Kripal Singh Lakhi Geoffrey Lawrence Ajayan Vinu

Recently, mesoporous carbon nitride (MCN) has aroused extensive interest for its potential applications in organocatalysis, photo- and electrochemistry and CO2 capture. However, further surface functionalization of MCN for advanced nanomaterials and catalysis still remains very challenging. Here we show that acidic carboxyl groups can be smoothly introduced onto the surface of well-ordered MCN ...

Journal: :IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) 2022

The reaction of levulinic acid production from glucose has a stage that requires high temperature and activation energy so in this catalyst is needed. required must have lewis site bronsted the acidity very influential for successful levulonic acid. Silica nickel phosphate catalysts sites Ni metal phosphoric silica groups. was measured using pyridine ammonia adsorption method center strength TG...

Journal: :RNA 2001
S P Ryder A K Oyelere J L Padilla D Klostermeier D P Millar S A Strobel

Tertiary structure in globular RNA folds can create local environments that lead to pKa perturbation of specific nucleotide functional groups. To assess the prevalence of functionally relevant adenosine-specific pKa perturbation in RNA structure, we have altered the nucleotide analog interference mapping (NAIM) approach to include a series of a phosphorothioate-tagged adenosine analogs with shi...

2015
Priyanka Srivastava Pratima Jain

An efficient and facile synthesis of fatty acid methyl esters (FAMEs) using sunflower oil and methanol has been carried out in the presence of a solid base Mg-Al-CO3 hydrotalcite heterogeneous catalyst. This protocol promotes the environment friendly conditions as the hydrotalcites are non toxic, recyclable, takes less reaction time and is easy to work up. The hydrotalcite showed high activity ...

Journal: :Chemical science 2017
Jun Liang Rui-Ping Chen Xiu-Yun Wang Tao-Tao Liu Xu-Sheng Wang Yuan-Biao Huang Rong Cao

A bifunctional imidazolium functionalized zirconium metal-organic framework (Zr-MOF), (I-)Meim-UiO-66 (2), was successfully prepared from the imidazole-containing Zr-MOF Im-UiO-66 (1) by a post-synthetic modification (PSM) method. It was found that the crystal size and pore features of the imidazole-containing 1 could be tuned at the nanoscale. The bifunctional MOF 2, containing Brønsted acid s...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید