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排序方式: 共有186条查询结果,搜索用时 15 毫秒
71.
72.
Micron-sized monodispersed stimuli-responsive polys’ (PS)/poly(2-dimethylaminoethyl methacrylate-N-isopropyl acrylamide-ethylene glycol dimethacrylate) [P(DM-NIPAM-EGDM)] composite polymer particles were prepared by seeded
copolymerisation of DM, NIPAM and EGDM with PS seed particles. Adsorption behaviour of trypsin suggested that composite particles
surface has both temperature- and pH-responsive swelling–deswelling characteristics. The performance of composite polymer
particles as a carrier for biomolecules in adsorption/release experiments was evaluated by measuring the specific activities
of adsorbed trypsin as a function of temperature and pH. 相似文献
73.
S. M. Al-Jobori M. J. Al-Atia M. Jalil A. K. Hussien 《Journal of Radioanalytical and Nuclear Chemistry》1990,139(1):31-36
Rock samples which contain relatively high concentrations of uranium may create problems of interference produced by fission products, when instrumental neutron activation analysis is used. The isotopes95Zr,140La,141Ce, 143Ce and 147Nd, which are commonly used in the neutron activation analysis of the corresponding elements, are also produced as fission products of235U. For each of these radioisotopes, a contribution factor is calculated theoretically and meaured experimentally using geological samples with different uranium contents. 相似文献
74.
Cocoa and cocoa products have received much attention due to their significant polyphenol contents. Cocoa and cocoa products, namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present varied polyphenol contents and possess different levels of antioxidant potentials. For the past ten years, at least 28 human studies have been conducted utilizing one of these cocoa products. However, questions arise on which of these products would deliver the best polyphenol contents and antioxidant effects. Moreover, the presence of methylxanthines, peptides, and minerals could synergistically enhance or reduce antioxidant properties of cocoa and cocoa products. To a greater extent, cocoa beans from different countries of origins and the methods of preparation (primary and secondary) could also partially influence the antioxidant polyphenols of cocoa products. Hence, comprehensive studies on the aforementioned factors could provide the understanding of health-promoting activities of cocoa or cocoa products components. 相似文献
75.
Ethylene polymerization was carried out by using a group of new dizirconium(IV) tetrapyrrole complexes as catalysts and MAO as co-catalyst under 1 atmosphere pressure of ethylene gas at 25 and 40°C. The highest value of catalyst activity was obtained
at 40°C by using bizirconium complexes including one calix[4]pyrrole between two zirconium centers and two terminal chlorines,
while zirconium(IV) complexes with coordinated THF, almost have not catalytic activity. The maximum catalytic activity mounted to 830 kg/mol·bar·h by Zr2(Cy4
Pyr
4)Cl4. The results show that the structure of the coordination sphere of zirconium(IV) has great influence on the rate of polymerization,
molar masses of forming polymer, and its molecular mass distribution.
Correspondence: Sajjad Mohebbi, Chemistry Department, University of Kurdistan, P.O. Box 66176-416, Sanandaj, Iran. 相似文献
76.
Mohammad Shahabuddin Md Jalil Miah Ken-ichi Iimura Takao Kimura Michinori Karikomi 《Tetrahedron letters》2017,58(13):1334-1337
A new class of amphiphilic oxa[9]helicene derivatives were synthesized in excellent-to-fair yields, and successfully characterized by different analytical techniques (e.g., FT-IR, 1H and 13C NMR, and HRMS). The compounds were enantiomerically separated by chiral HPLC and the absolute configurations of the enantiomers were confirmed by circular dichroism spectroscopy. Other optical properties (e.g., UV, photoluminescence, specific optical rotation and molecular optical rotation) of the newly synthesized compounds were also examined. 相似文献
77.
Taghavizadeh Yazdi Mohammad Ehsan Khara Jalil Sadeghnia Hamid Reza Esmaeilzadeh Bahabadi Sedigheh Darroudi Majid 《Research on Chemical Intermediates》2018,44(2):1325-1334
Research on Chemical Intermediates - Silver nanoparticles (Ag-NPs) were synthesized through a facile and “green” method, which uses the aqueous shoots extract of Rheum turkestanicum at... 相似文献
78.
Jalil Rashidinia Babak Azarnavid 《Communications in Nonlinear Science & Numerical Simulation》2012,17(1):227-234
We study the backward heat conduction problem in an unbounded region. The problem is ill-posed, in the sense that the solution if it exists, does not depend continuously on the data. Continuous dependence of the data is restored by cutting-off high frequencies in Fourier domain. The cut-off parameter acts as a regularization parameter. The discrepancy principle, for choosing the regularization parameter and double exponential transformation methods for numerical implementation of regularization method have been used. An example is presented to illustrate applicability and accuracy of the proposed method. 相似文献
79.
Arsalan Mirjafari Niloufar Mobarrez James H. Davis Jr Jalil Noei 《Comptes Rendus Chimie》2011,14(12):1065-1070
A wide variety of oximes were prepared from different types of alcohols with hydroxylamine hydrochloride using 1-methylimidaziloum nitrate, [Hmim][NO3], ionic liquid as a reaction medium and promoter under microwave irradiation. This protocol provides a one-pot oxime synthesis with high yields that is facile, eco-friendly and the ionic liquid can be recovered and reused. 相似文献
80.
Mohammad Mehdi Papari Reza Behjatmanesh-Ardakani Masoumeh Kiani Jalil Moghadasi Antonio Campo 《Colloid and polymer science》2011,289(10):1081-1087
This paper addresses a method for predicting the participating constants in equation of state (EOS) for compressed polymeric
fluids using two scaling constants, the surface tension γ
g and the molar density ρ
g, both at the glass transition point. The theoretical EOS undertaken is the one attributed to Tao and Mason. The second virial
coefficients are calculated from a two-parameter corresponding states correlation, which is constructed with two constants
as scaling parameters, i.e., the surface tension γ
g and the molar density ρ
g. This new correlation has been applied to the Tao–Mason (TM) EOS to predict the volumetric behavior of several polymer melts.
The operating temperature range is from 291.25 to 603.4 K and pressures of up to 202.5 MPa. A collection of 516 data points
has been examined for the aforementioned polymers. The average absolute deviation between the calculated densities and the
experimental ones is of the order of 0.44%. 相似文献