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91.
Bakr F. Abdel‐Wahab Hanan A. Mohamed Rizk E. Khidre Mohamed F. El‐Mansy 《Journal of heterocyclic chemistry》2014,51(5):1215-1232
Published data on the methods of preparation of different azoles linked directly to oxadiazoles are described systematically. This review is divided into classes based on the number of heteroatoms in the azoles connected to oxadiazole ring, and the subtitles are divided according to the type of oxadiazoles isomer. 相似文献
92.
Melina Knezevic Michael Heilmann Giovanni Maria Piccini Konrad Tiefenbacher 《Angewandte Chemie (International ed. in English)》2020,59(30):12387-12391
The site‐selective C?H oxidation of unactivated positions in aliphatic ammonium chains poses a tremendous synthetic challenge, for which a solution has not yet been found. Here, we report the preferential oxidation of the strongly deactivated C3/C4 positions of aliphatic ammonium substrates by employing a novel supramolecular catalyst. This chimeric catalyst was synthesized by linking the well‐explored catalytic moiety Fe(pdp) to an alkyl ammonium binding molecular tweezer. The results highlight the vast potential of overriding the intrinsic reactivity in chemical reactions by guiding catalysis using supramolecular host structures that enable a precise orientation of the substrates. 相似文献
93.
A. Abu-El-Hassan M. Abdel Wahab M. Y. El-Bakry M. Zidan 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1996,47(2):313-332
The isothermal, stationary and isochoric flow of a fluid of grade two between a pair of rotating eccentric spheres is investigated. The equations of motion of first and second order are formulated and solved for the first order only. However, the equation of second order indicates the presence of secondary flow. The stress distributions are computed and used to determine the resultant forces and torques acting on the stationary outer sphere. An important result for rheometry is that the resultant torques can be used to determine the coefficient of viscosity, while the resultant force in the direction of the axis of symmetry may be employed to determine the second normal stress difference. 相似文献
94.
Riscob B Shakir M Sundar JK Natarajan S Wahab MA Bhagavannarayana G 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(1):543-548
Glycine glutaric acid, a new organic compound has been synthesized and good quality single crystals were grown by slow evaporation technique. The structure of the grown crystal was elucidated by using single crystal XRD. The presence of the functional groups was confirmed by using FT-IR spectroscopy. The optical transparency was studied by using UV-vis spectrophotometer and it was found that the crystal is having high optical transparency. The thermal stability of the crystal was studied by using thermo-gravimetric and differential thermal analyses and found that it is stable up to 150°C. The room temperature dielectric studies were also carried out over the wide frequency range: 10 mHz to 10 MHz. 相似文献
95.
Serrano MC Vavra AK Jen M Hogg ME Murar J Martinez J Keefer LK Ameer GA Kibbe MR 《Macromolecular bioscience》2011,11(5):700-709
The synthesis of poly(diol-co-citrate) elastomers that are biocompatible with vascular cells and can modulate the kinetics of the NO release based on the diol of selection is reported. NO-mediated cytostatic or cytotoxic effects can be controlled depending on the NO dose and the exposure time. When implanted in vivo in a rat carotid artery injury model, these materials demonstrate a significant reduction of neointimal hyperplasia. This is the first report of a NO-releasing polymer fabricated in the form of an elastomeric perivascular wrap for the treatment of neointimal hyperplasia. These elastomers also show promise for other cardiovascular pathologies where NO-based therapies could be beneficial. 相似文献
96.
Mohd. Shakir V. GaneshB. Riscob K.K. MauryaM.A. Wahab G. BhagavannarayanaK. Kishan Rao 《Physica B: Condensed Matter》2011,406(18):3392-3397
Pure and l-alanine (LA) doped single crystals of potassium dihydrogen orthophosphate (KDP) were grown by slow evaporation solution technique (SEST) in aqueous solution at ambient temperature. Powder X-ray diffraction study was done to confirm the crystal system and lattice parameters of KDP. No additional phases were observed at all doping concentrations (1-7.5 mol%), which was further confirmed by FT-Raman spectroscopy analysis. The influence of LA doping on the crystalline perfection was assessed by high-resolution X-ray diffractometry (HRXRD) analysis. HRXRD studies revealed that the grown crystals could accommodate LA at the interstitial positions in the crystalline matrix of KDP up to some critical concentration without any deterioration in the crystalline perfection. Above this concentration, very low angle structural grain boundaries were developed and it seems that the excess LA above the critical concentration was segregated along the grain boundaries. The SHG efficiency was measured using the Kurtz powder technique. The relative SHG efficiency of the crystals was found to be increased with doping concentration up to 5 mol% and above this it decreases. Optical transmission study also revealed the same behavior with enhancement up to 5 mol% concentration and later decreased. The hardness values were found to be increased by increasing the doping concentration. 相似文献
97.
Abdulrhman Alsayari Abdullatif Bin Muhsinah Dalia Almaghaslah Sivakumar Annadurai Shadma Wahab 《Molecules (Basel, Switzerland)》2021,26(13)
Respiratory tract infections are underestimated, as they are mild and generally not incapacitating. In clinical medicine, however, these infections are considered a prevalent problem. By 2030, the third most comprehensive reason for death worldwide will be chronic obstructive pulmonary disease (COPD), according to the World Health Organization. The current arsenal of anti-inflammatory drugs shows little or no benefits against COPD. For thousands of years, herbal drugs have been used to cure numerous illnesses; they exhibit promising results and enhance physical performance. Ginseng is one such herbal medicine, known to alleviate pro-inflammatory chemokines and cytokines (IL-2, IL-4, IFN-γ, TNF-α, IL-5, IL-6, IL-8) formed by macrophages and epithelial cells. Furthermore, the mechanisms of action of ginsenoside are still not fully understood. Various clinical trials of ginseng have exhibited a reduction of repeated colds and the flu. In this review, ginseng’s structural features, the pathogenicity of microbial infections, and the immunomodulatory, antiviral, and anti-bacterial effects of ginseng were discussed. The focus was on the latest animal studies and human clinical trials that corroborate ginseng’s role as a therapy for treating respiratory tract infections. The article concluded with future directions and significant challenges. This review would be a valuable addition to the knowledge base for researchers in understanding the promising role of ginseng in treating respiratory tract infections. Further analysis needs to be re-focused on clinical trials to study ginseng’s efficacy and safety in treating pathogenic infections and in determining ginseng-drug interactions. 相似文献
98.
99.
Since the experimental observation of the violation of the Bell-CHSH inequalities, much has been said about the non-local and contextual character of the underlying system. However, the hypothesis from which Bell’s inequalities are derived differ according to the probability space used to write them. The violation of Bell’s inequalities can, alternatively, be explained by assuming that the hidden variables do not exist at all, that they exist but their values cannot be simultaneously assigned, that the values can be assigned but joint probabilities cannot be properly defined, or that averages taken in different contexts cannot be combined. All of the above are valid options, selected by different communities to provide support to their particular research program. 相似文献
100.
In-vitro-labelling of vasopressin and tofranil using radioactive iodine and lechnelium, is carried out by direct interaction between nascent halogen and the macromolecules. Labelling takes place at the favourable pH in the tyrosyl residue of the molecule, yielding a die-iodo derivative or similar. The present method had the advantage of being simple rapid and gives labelled compounds of high specific activity. The gel-filtration method furnished labelled compounds with a minimum degradation products. 相似文献