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991.
Direct reductive amination of aldehydes and ketones were accomplished efficiently using high-capacity, ionene-based, polymer-supported borohydride reagent in isopropyl alcohol at reflux under neutral conditions. The reagent is easily prepared by mixing aqueous solution of 2,4-ionene bromide with an alkaline solution of sodium borohydride at room temperature. The generality of reaction was established using both aliphatic and aromatic aldehydes, ketones, and amines. 相似文献
992.
Majid M. Heravi Samaheh Sadjadi Negar Mokhtari Haj Hossein A. Oskooie Fatemeh F. Bamoharram 《合成通讯》2013,43(6):861-867
4-Aminoquinazolines were synthesized in good yields via a one-pot, three-component reaction of anthranilonitrile, acylchlorides, and ammonium acetate in the presence of catalytic amounts silica-supported Preyssler nanoparticles under refluxing conditions. 相似文献
993.
Biologically active pyrano[2,3-d]pyrimidine derivatives were efficiently synthesized in excellent yields by a three-component, one-pot condensation reaction of malononitrile, benzaldehydes, and barbituric acid using a catalytic amount of Zn[(L)proline]. 相似文献
994.
Akram Safari-Hafshejani Alireza Amini-Harandi Majid Fakhar 《Numerical Functional Analysis & Optimization》2019,40(5):603-619
In this article, in the setting of metric spaces we introduce the notions of noncyclic and cyclic Fisher quasi-contraction mappings. We establish the existence of an optimal pair of fixed points for a noncyclic Fisher quasi-contraction mapping and iterative algorithms are furnished to determine such optimal pair of fixed points. For a cyclic Fisher quasi-contraction mapping, we also study the existence of best proximity points. Presented results extend and improve some recent results in the literature. 相似文献
995.
Molecular Diversity - Layered double hydroxides (LDHs) are recognized as two-dimensional (2D) clay materials, which comprise the interlayer anions and host layers with a positive charge... 相似文献
996.
N. Siddique A. Majid M. Tufail 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(3):691-699
A study was undertaken to assess the air quality of Lahore by the elemental analysis of air conditioner (AC) filter dust samples
collected from 15 different commercial sites. Samples were prepared using the Leeds Public Analyst Method and were analyzed
using instrumental neutron activation analysis (INAA) for up to 31 elements. The elements Al, As, Ba, Ce, Co, Cr, Cs, Fe,
Hf, K, La, Lu, Mn, Na, Nd, Rb, Sc, Sm, Sn, Ta, Th, Yb and Zn were detected in all 15 samples whereas the remaining elements
have been detected in fewer samples; i.e. Mg, Sb and Tb were detected in 14 samples, Br and V in ten samples, U in nine samples
and Ca and Ti in eight samples only. Al, Ca, Fe, K, Mg and Na were determined in all samples at percentage levels. The concentrations
of most elements were found to lie around the mean values for the 15 samples studied and were not orders of magnitude different.
However the concentrations of Ca, Mg, Sn and Zn were found to be more variable and were found to be dependant on activities
such as construction, fruit and vegetable handling, tin plating and transport, respectively. 相似文献
997.
Amir Reza Jalilian Seyyedeh Leila Hosseini-Salekdeh Morteza Mahmoudi Hassan Yousefnia A. Majdabadi Majid Pouladian 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(1):119-127
In this study, superparamagnetic iron oxide nanoparticles (SPION) embedded by folic acid (SPION-folate) were prepared by a
modified co-precipitation method. The structure, size, morphology, magnetic property and relaxivity of the SPION-folate were
characterized systematically by means of XRD, VSM, HRSEM and TEM and the interaction between folate and iron oxide (Fe3O4) was characterized by FT-IR. The particle size was shown to be ≈5–10 nm. To ensure biocompatibility, the interaction of these
SPION with mouse connective tissue cells (adhesive) was investigated using an MTT assay. Consequently, gallium-67 labeled
nanoparticles ([67Ga]-SPION-folate) were prepared using 67Ga with a high labeling efficiency (over 96%, RTLC method) and they also showed an excellent stability at room temperature
for at least 2 days and were evaluated for their biodistribution in normal rats up to 24 h compared with free Ga3+ cation and [67Ga]-SPION biodistribution. The biodistribution of the tracer among 3 other folate tracers were compared, showing lower liver
uptake and higher blood circulation after 24 h leading to better bioavailability. The bone:muscle, kidney:muscle, lung:muscle,
stomach:muscle ratios were 9.3, 9.32, 7.6 and 5.83 respectively. The developed folate-containing nano-system can be an interesting
folate receptor tracer, capable of better cell membrane permeability while possessing paramagnetic properties for thermotherapy. 相似文献
998.
Montazer M Lessan F Pajootan E Dadashian F 《Applied biochemistry and biotechnology》2011,165(2):748-759
Trans-glutaminases is known as a cross-linking enzyme for proteins. Wool is a proteinous fiber conventionally is treated through
several processes to obtain the desirable characteristics. Bleaching is also one of the most important processes usually carried
out by using an oxidizing agent in a conventional method. The tensile strength of wool yarns was reduced as a consequence
of oxidative bleaching. Here, with the help of microbial trans-glutaminases (m-TGases), a novel bleaching process was disclosed
in a way to obtain a bleached wool yarn with no significant reduction in the tensile strength. The results confirmed that
the bleached wool yarns with H2O2 could be modified by m-TGases post-treatment. The m-TGases treatment on the bleached wool yarns improved the tensile strength
and whiteness along with the higher alkali resistance. 相似文献
999.
Hadi Kargar Majid MoghadamValiollah Mirkhani Shahram TangestaninejadIraj Mohammadpoor-Baltork Mahmood Naghipour 《Polyhedron》2011,30(9):1463-1468
In the present work, the dehydrogenation of 2-substituted imidazolines with sodium periodate in the presence of tetraphenylporphyrinatomanganese(III) chloride supported on polystyrene-bound imidazole, [Mn(TPP)Cl@PSI] is reported. A wide variety of 2-imidazolines were efficiently converted to their corresponding imidazoles by the [Mn(TPP)Cl@PSI]/NaIO4 catalytic system in a 1:2 CH3CN/H2O mixture under agitation with magnetic stirring. Ultrasonic irradiation enhanced the catalytic activity of this catalyst in the oxidation of 2-imidazolines and this led to shorter reaction times and higher product yields. This catalyst could be reused several times without significant loss of its catalytic activity. 相似文献
1000.
Issa Yavari Majid Ghazanfarpour‐Darjani Yazdan Solgi Salomeh Ahmadian 《Helvetica chimica acta》2011,94(4):639-642
An efficient synthesis of functionalized 2‐(1,3‐oxathiolan‐2‐ylidene)malononitriles containing a push‐pull C?C bond via a simple reaction between malononitrile, CS2, and oxiranes in the presence of Et3N is described (Scheme 1). 相似文献