نتایج جستجو برای: organosuperbases sba 15

تعداد نتایج: 497698  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه مازندران - دانشکده شیمی 1392

در این رساله، ترکیبات هتروسیکلی مهم دارویی نظیر پیریدو[3?2-d]پیریمیدین ها و اسپیرواکسیندول ها در آب و اتانول به عنوان حلال های سبز در بازده های بالا با استفاده از کاتالیزگرهای سیلیکای مزوحفره sba-15 عامل دار شده با اسید یا باز آلی سنتز شدند. همچنین فعالیت آنتی اکسیدانی تعدادی از این ترکیبات سنتزی مورد بررسی قرارگرفتند. در بخش دوم کار تحقیقاتی، محتوای تام فنولی و فلاونوییدی، فعالیت های آنتی اکس...

Journal: :Physical chemistry chemical physics : PCCP 2013
Matthias Ide Mohamad El-Roz Els De Canck Aurélie Vicente Tom Planckaert Thomas Bogaerts Isabel Van Driessche Frédéric Lynen Veronique Van Speybroeck Frédéric Thybault-Starzyk Pascal Van Der Voort

IR and NMR spectroscopy were used to determine the silanol content in the most common mesoporous ordered silicas: MCM-41, MCM-48, SBA-15 and SBA-16. In addition, a spray dried MCM-41 and an ethene bridged PMO are investigated. The results are compared with a commercial chromatographic silica (Nucleosil). The complete distribution of surface and bulk silanols, and of isolated, geminal and vicina...

Journal: :Chemical communications 2010
Liang Wang Xiangju Meng Bin Wang Wenyang Chi Feng-Shou Xiao

Au nanoparticles with small sizes (2-3 nm) were effectively stabilized in the mesopores of (S)-(-)-2-pyrrolidinone-5-carboxylic acid-modified SBA-15, which showed superior catalytic properties in aerobic oxidation of alcohols, compared with pyrrolidone-free SBA-15 supported Au catalysts.

2010
YL Xue P Wu Y Liu X Zhang L Lin Q Jiang

SiO(2) mesoporous molecular sieve SBA-15 with the incorporation of erbium ions is studied as a novel type of nanoscopic composite photoluminescent material in this paper. To enhance the photoluminescence efficiency, two schemes have been used for the incorporation of Er(3+) where (1) Er(3+) is ligated with bis-(perfluoromethylsulfonyl)-aminate (PMS) forming Er(PMS)(x)-SBA-15 and (2) Yb(3+) is c...

Journal: :Chemical communications 2005
Richard L Brutchey Ian J Drake Alexis T Bell T Don Tilley

A new pseudo-tetrahedral Co(II) complex has been grafted onto the surface of SBA-15 and successfully utilized for the catalytic oxidization of alkylaromatic substrates with tert-butyl hydroperoxide (TBHP)via an H-atom transfer mechanism.

2010
Huayu Huang Yongsheng Ji Zhenfeng Qiao Chuande Zhao Jianguo He Haixia Zhang

Magnetic Fe-SBA-15 mesoporous silica molecular sieves were prepared, characterized, and used for magnetic separation. Wet impregnation, drying, and calcination steps led to iron inclusion within the mesopores. Iron oxide was reduced to the metal form with hydrogen, and the magnetic Fe-SBA-15 was obtained. Fourier-transform infrared spectroscopy confirmed the preparation process from the oxide t...

Journal: :Langmuir : the ACS journal of surfaces and colloids 2006
Huan Wang Frank L Y Lam Xijun Hu Ka Ming Ng

An ordered mesoporous carbon, CMK-3, was synthesized using a mesoporous siliceous material, SBA-15, as the template. CMK-3 was characterized and used for the adsorption of fullerenes C60 and C70. It was found that the adsorption capacity of CMK-3 is 4 times higher than that of activated carbon. The adsorption equilibrium isotherms of C60 and C70 on CMK-3 were studied for both single and binary ...

Journal: :Nanoscale 2012
Min Xue Dennis Cao J Fraser Stoddart Jeffrey I Zink

pH-responsive megagates have been fabricated around mesoporous silica material SBA-15 in order to mechanize the mesopores. These megagates remain closed in neutral conditions, but open at pH 5. The capping components of the megagates were designed to be capable of controlling pores up to 6.5 nm in diameter. Selectivity of payloads with different sizes can be achieved through the use of differen...

1980
Rahmat Ahmad Zuhairi Abdullah Abdul Rahman Mohamed

Problem statement: Santa Barbara Amorphous (SBA-15) is significant mesoporous silica with exclusive and important properties of highly ordered mesopores, hydrothermally stable and thick wall, profusely large surface area and huge pore volume which render it as promising catalyst for wide applications. However, the purely siliceous SBA-15 which lacks of acidity characteristic hinders its ideal c...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی اصفهان - دانشکده عمران و محیط زیست 1391

آلودگی اکوسیستم های آبی به رنگ ها یکی از اصلی ترین معضلات زیست محیطی قرن حاضر است که نیازمند ارائه راه حل های فوری و موثر در جهت حذف این آلاینده ها می باشد. بسیاری از صنایع مانند رنگرزی، نساجی، کاغذ و پلاستیک از رنگ ها و حجم زیادی آب برای رنگ کردن محصولات خود استفاده می کنند. بدین ترتیب مقدار زیادی پساب حاوی رنگ تولید می شود. بسیاری از آنها سمی و سرطان زا هستند و وجود آنها برای ادامه حیات آبزیا...

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