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71.
Gul R. Badshah A. Altaf A. Ali Tabassum S. Zia M. 《Russian Journal of General Chemistry》2017,87(11):2684-2689
Russian Journal of General Chemistry - Six new ferrocenyl guanidines were synthesized and characterized by elemental analysis, FT-IR and 1H and 13C NMR. Compounds 1–6 were screened for... 相似文献
72.
Thierry Maré Salma Halelfadl Ousmane Sow Patrice Estellé Steven Duret Frederic Bazantay 《Experimental Thermal and Fluid Science》2011,35(8):1535-1543
The objective of this study is to compare experimentally the thermal performances of two types of commercial nanofluids. The first is composed of oxides of alumina (γAl2O3) dispersed in water and the second one is aqueous suspensions of nanotubes of carbons (CNTs). The viscosity of the nanofluids is measured as a function of the temperature between 2 and 10 °C. An experimental device, containing three thermal buckles controlled in temperature and greatly instrumented permits to study the thermal convective transfers. The evolution of the convective coefficient permits to study the convective thermal transfers. The evolution of the convective coefficient is presented according to the Reynolds number, at low temperature from 0 to 10 °C and for the two aforementioned nanofluids. An assessment of the pressure drops in the circuit as well as of the powers of the circulator and outputs is dealt with. 相似文献
73.
74.
Arjmand F Sharma GC Sayeed F Muddassir M Tabassum S 《Journal of photochemistry and photobiology. B, Biology》2011,105(3):167-174
N,N-bis[(R-/S-)-1-benzyl-2-ethoxyethane] tin (IV) complexes were synthesized by applying de novo design strategy by the condensation reaction of (R-/S-)2-amino-2-phenylethanol and dibromoethane in presence of dimethyltin dichloride and thoroughly characterized by elemental analysis, conductivity measurements, IR, ESI-MS, (1)H, (13)C and (119)Sn, multinuclear NMR spectroscopy and XRD study. Enantioselective and specific binding profile of R-enantiomer 1 in comparison to S-enantiomer 2 with ultimate molecular target CT-DNA was validated by UV-visible, fluorescence, circular dichroism, (1)H and (31)P NMR techniques. This was further corroborated well by interaction of 1 and 2 with 5'-GMP. 相似文献
75.
Sartaj Tabassum Rais Ahmad Khan Subrata Sen Aarti S. Juvekar 《Journal of organometallic chemistry》2011,696(8):1600-2895
New glycosyl derived ligand and its complexes, with SnCl4·5H2O (1) and (CH3)2SnCl2(2) were synthesized and characterized by spectroscopic (IR, 1H, 13C, and 119Sn NMR, UV-vis, ESI-MS) and analytical methods. Interaction studies of 1 and 2 with CT DNA were studied by using various biophysical techniques, which showed high binding affinity of 2 with CT DNA. In vitro cytotoxicity of complexes 1 and 2 were evaluated against different human cancer cell lines of different histological origins by employing SRB Assay. The organotin(IV) complex 2 exhibited remarkable activity against DWD (oral cancer) cell lines with GI50 values <10 μg/ml. Complex 2 induced apoptosis of DWD cell line at a very low concentration of 1-4 μg/mL. 相似文献
76.
Yahya Salma Stéphanie BallereauSonia Ladeira Christine LepetitRemi Chauvin Nathalie Andrieu-AbadieYves Génisson 《Tetrahedron》2011,67(23):4253-4262
An optimized synthesis of jaspine B analogues bearing an n-octyl or a p-fluorophenethyl lipophilic appendage was developed. Key to the approach was the use of acetylenic nucleophiles for the stereocontrolled introduction of the side chain and the implementation of a novel cyclization procedure to build the tetrahydrofuran ring. Three N-substituted amine or amide derivatives were also accessed. The biological activity of these four jaspine B analogues was shown to strongly depend on the nature of both the N-substituent and the aliphatic moiety connected to the tetrahydrofuran ring. Gratifyingly, the truncated jaspine B derivative proved to be a pro-apoptotic inhibitor of the conversion of ceramide into sphingomyelin. Finally, the efficient formation of a fused bis-furan derivative according to a 5-endo-dig process was observed under saponification conditions. On the basis of a theoretical study, a mechanistic pathway was delineated highlighting the Lewis acidity of the K+ ion as the driving force for this transformation in a strongly alkaline medium. 相似文献
77.
We consider several multiscale-in-time kinetic Monte Carlo models, in which some variables evolve on a fast time scale, while the others evolve on a slow time scale. In the first two models we consider, a particle evolves in a one-dimensional potential energy landscape which has some small and some large barriers, the latter dividing the state space into metastable regions. In the limit of infinitely large barriers, we identify the effective dynamics between these macro-states, and prove the convergence of the process towards a kinetic Monte Carlo model. We next consider a third model, which consists of a system of two particles. The state of each particle evolves on a fast time-scale while conserving their respective energy. In addition, the particles can exchange energy on a slow time scale. Considering the energy of the first particle, we identify its effective dynamics in the limit of asymptotically small ratio between the characteristic times of the fast and the slow dynamics. For all models, our results are illustrated by representative numerical simulations. 相似文献
78.
Ather Farooq Khan Muhammad Awais Abdul Samad Khan Sobia Tabassum Aqif Anwar Chaudhry Ihtesham Ur Rehman 《应用光谱学评论》2013,48(4):329-355
Abstract Raman spectroscopy of natural bones and hydroxyapatites is described. In addition, how Raman spectroscopy has proved crucial in providing baseline data for the modification of synthetic apatite powders that are routinely used now as bone replacement materials is explained. It is important to understand the chemical structural properties of natural bone. Bone consists of two primary components: an inorganic or mineral phase, which is mainly a carbonated form of a nanoscale crystalline calcium phosphate, closely resembling hydroxyapatite, and an organic phase, which is composed largely of type I collagen fibers. Other constituents of bone tissue include water and organic molecules such as glycosaminoglycans, glycoproteins, lipids, and peptides. Ions such as sodium, magnesium, fluoride, and citrate are also present, as well as hydrogenophosphate. Hence, the mineral phase in bone may be characterized essentially as nonstoichiometric substituted apatite. Such a distinction is important in the development of synthetic calcium phosphates for application as skeletal implants. An understanding of bone function and its interfacial relationship to an implant clearly depends on the associated structure and composition. Therefore, it is essential to fully understand the chemical composition of bone, and Raman spectroscopy is an excellent technique for such an analysis. 相似文献
79.
Let K be a compact subgroup of automorphisms of ? n . We formulate and prove an analogue of Miyachi’s theorem for the semi-direct product K ? ? n . This allows us to solve the sharpness problems in the theorem of Cowling-Price and in the L p ? L q analogue of Morgan theorem for any compact extension of ? n . These upshots are proved using the representations theory and the Plancherel formula for the group Fourier transform. 相似文献
80.