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101.
Ji Kaifang Chen Xuegao Aldahan Ala Yi Peng Murad Ahmed Hussein Saber Alshamsi Dalal Ahmed Mohamad M. Yu Zhongbo 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1055-1070
Journal of Radioanalytical and Nuclear Chemistry - Estimating groundwater recharge rate is essential for water sustainability of the arid region of the United Arab Emirates that receives most... 相似文献
102.
Palladium–quaternary phosphonium phase transfer catalyst brush assembly as reusable and environmentally benign catalyst for coupling of aryl halides and sodium tetraphenylborate in neat water
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A first example of simultaneous covalent anchoring of a palladate anion–phosphonium cation matrix on the surface of silica nanoparticles and application in the Suzuki coupling reaction of a variety of different haloarenes and sodium tetraphenylborate in neat aqueous media without the addition of any organic co‐solvent are described. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
103.
104.
Najmedin Azizi Mohammad R. Saidi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1255-1259
The f -hydroxy phosphonates are readily prepared by treating aromatic or aliphatic aldehydes and ketones with trialkylphosphite in the presence of trimethylsilylchloride in a very short time and in almost quantitative yields. 相似文献
105.
106.
Maryam Abrishamkar Seyed Naser Azizi Jahan Bakhsh Raoof 《Monatshefte für Chemie / Chemical Monthly》2012,14(5):409-412
Abstract
Methanol is used as a fuel in the direct methanol fuel cell. Direct oxidation of methanol encounters large overvoltages at most unmodified electrode surfaces. The development of new procedures for electrocatalytic oxidation of methanol to decrease this overvoltage is therefore very desirable. In this paper, we report a new zeolite-modified carbon paste electrode based on Ni-ZSM-5 for methanol electrooxidation. Nanocrystallites of ZSM-5 (Si/Al of 50) with average particle size of 58 nm were synthesized using clear solutions at low temperature (90 °C) under atmospheric pressure. Ni(II) ions were incorporated into the zeolite by immersion of the modified carbon paste electrode with synthesized zeolite in a 1.0 M nickel chloride solution. Cyclic voltammetry showed that by using nano-sized zeolite, the oxidation current increased compared with that of micron-sized zeolite crystallites. 相似文献107.
Superparamagnetic tungstophosphoric acid supported on silica-encapsulated γ-Fe2O3 was used as an efficient catalyst for the direct oxidation of secondary amines to nitrones with hydrogen peroxide as the oxidant. The catalyst could be recycled up to four times without significant loss of activity. 相似文献
108.
109.
Saber Elaydi 《Journal of Difference Equations and Applications》2013,19(12):1873-1877
We present open problems and conjectures for some two-dimensional competition models, namely the logistic competition model and a Ricker-type competition model. 相似文献
110.
It is well known by results of Golod and Shafarevich that the Hilbert 2-class field tower of any real quadratic number field, in which the discriminant is not a sum of two squares and divisible by eight primes, is infinite. The aim of this article is to extend this result to any real abelian 2-extension over the field of rational numbers. So using genus theory, units of biquadratic number fields and norm residue symbol, we prove that for every real abelian 2-extension over ? in which eight primes ramify and one of theses primes ≡ ?1 (mod 4), the Hilbert 2-class field tower is infinite. 相似文献