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11.
Tentu Nageswara Rao Suliman Yousef AlOmar Faheem Ahmed Fadwa Albalawi Naushad Ahmad Nalla Krishna Rao M. V. Basaveswara Rao Ravi Kumar Cheedarala G. Rajasekhar Reddy Tentu Manohra Naidu 《Molecules (Basel, Switzerland)》2021,26(14)
In this article, a zirconia-based nano-catalyst (Nano-ZrO2), with intermolecular C-N bond formation for the synthesis of various benzimidazole-fused heterocycles in a concise method is reported. The robustness of this reaction is demonstrated by the synthesis of a series of benzimidazole drugs in a one-pot method. All synthesized materials were characterized using 1HNMR, 13CNMR, and LC-MS spectroscopy as well as microanalysis data. Furthermore, the synthesis of nano-ZrO2 was processed using a standard hydrothermal technique in pure form. The crystal structure of nano-ZrO2 and phase purity were studied, and the crystallite size was calculated from XRD analysis using the Debye–Scherrer equation. Furthermore, the antimicrobial activity of the synthesized benzimidazole drugs was evaluated in terms of Gram-positive, Gram-negative, and antifungal activity, and the results were satisfactory. 相似文献
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Faheem K. Butt Aliaksandr S. Bandarenka 《Journal of Solid State Electrochemistry》2016,20(11):2915-2928
Functional electrode materials play an increasingly important role in the advancement of energy conversion and storage technologies used in batteries, electrolyzers, supercapacitors, fuel cells, and other electrochemical devices. To address the problems related to accelerating demand for the so-called renewable energy, which are simultaneously coupled with environmental concerns, new generations of materials, engineering methodologies, and innovative techniques are necessary. Among many synthetic methods, microwave-assisted synthesis becomes nowadays a very popular approach to efficiently control both the composition and morphology of solids. In this review, we focus on its applications to create new advanced energy electrode materials. 相似文献
13.
Muzafar A. Kanjwal Faheem A. SheikhNasser A.M. Barakat Xiaoqiang LiHak Yong Kim Ioannis S. Chronakis 《Applied Surface Science》2012,258(8):3695-3702
In this study, a new hierarchical nanostructure that consists of zinc oxide (ZnO) was produced by the electrospinning process followed by a hydrothermal technique. First, electrospinning of a colloidal solution that consisted of zinc nanoparticles, zinc acetate dihydrate and poly(vinyl alcohol) was performed to produce polymeric nanofibers embedding solid nanoparticles. Calcination of the obtained electrospun nanofiber mats in air at 500 °C for 90 min produced pure ZnO nanofibers with rough surfaces. The rough surface strongly enhanced outgrowing of ZnO nanobranches when a specific hydrothermal technique was used. Methylene blue dihydrate was used to check the photocatalytic ability of the produced nanostructures. The results indicated that the hierarchical nanostructure had a better performance than the other form. 相似文献
14.
The performance of matrix assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF) of bacterial proteins strongly depends on sample preparation. It is found that the mass spectral profiles obtained from direct MALDI-TOF MS of the protein extracts are much weaker for individual bacterial cells than compared to those prepared by the Tris-EDTA buffer approach (TEBA). Characteristic mass spectral peaks were observed in the mass range from 3,000 to 15,000?Da. The mass peaks reported earlier and claimed to serve as species-specific biomarkers are consistently found here as well. Mass peaks at m/z of 3636, 5466, 5750, 6315, 6547, 7274, 9192, and 9742 are found for Escherichia coli studied and assigned as specific biomarkers. Similarly, specific mass peaks have been identified at m/z 5443, 7270, 7724, and 9888 for Bacillus subtilis, and at 3603, 5496, 6800, 8858 and 9531 for Serratia marcescens. The detection limits for the three target bacteria range from 2.4?×?105 to 3.3?×?105?cfu·mL-1. We conclude that the TE buffer approach can produce reliable data for rapid classification, high-resolution and highly sensitive detection of bacteria. Fig
The Tris-EDTA buffer approach is a sample preparation technique before MALDI-TOF MS analysis. In this study, the bacterial cells were treated with Tris-EDTA buffer for high resolution MALDI-TOF mass spectrometry. It is important to note that mass spectral profiles obtained from direct MALDI-TOF MS of protein extracts are much weaker for individual bacterial cells than compared to those prepared by the Tris-EDTA buffer approach. The current approach is very simple and rapid for high sensitive detection of bacteria. 相似文献
15.
Wael A. El‐Sayed Omar M. Ali Merfat S. Faheem Ibrahim F. Zied Adel A.‐H. Abdel‐Rahman 《Journal of heterocyclic chemistry》2012,49(3):607-612
New [1,2,4‐oxadiazolyl]methyl‐3H‐[1,2,3]triazolo[4,5‐d]pyrimidin derivatives were synthesized starting from N′‐Hydroxy‐1‐naphthimidamide. The N‐substituted acyclic nucleoside analogs as well as the substituted glycosides were also prepared by reaction with the corresponding reagents. The antimicrobial results indicated that most of the tested compounds exhibited moderate to high antimicrobial activity whereas few compounds were found to exhibit little or no activity against the tested microorganisms. 相似文献
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Saturated absorption spectroscopy is performed on the acetylene nu(1) + nu(3) band near 1532 nm inside photonic bandgap fibers of small (approximately 10 microm) and large (approximately 20 microm) core diameters. The observed linewidths are narrower in the 20 microm fiber and vary from 20 to 40 MHz depending on pressure and power. Variations in the background light transmission, attributed by others to surface modes, are significantly reduced in the 20 microm fiber. The optimum signal for use as a frequency reference in a 0.8 m long, 20 microm diameter fiber is found to occur at about 0.5 torr for 30 mW of pump power. The saturation power is found by modeling the propagation and attenuation of light inside the fiber. 相似文献
18.
Shamim Ahmad Mohammed Ali Shahid H. Ansari Faheem Ahmed 《Journal of Saudi Chemical Society》2010,14(4):409-412
Phytochemical investigation of the galls of Pistacia integerrima Stewart (Pistaceaceae) yielded three new phytoconstituents characterized as n-decan-3′-ol-yl-n-eicosanoate, n-octadecan-9,11-diol-7-one and 3-oxo-9β-lanost-1,20(22)-dien-26-oic acid along with the known compound β-sitosterol. The structures of these phytoconstituents have been elucidated on the basis of spectral data analysis and chemical reactions. 相似文献
19.
Muhammad Haji Hanif Muddasir Tahiri Iftikhar Ahmad Versiani Muhammad Ali Shah Faheem Khaliq Obaid Ali Syed Tahir Ahmed Safeer 《Research on Chemical Intermediates》2018,44(10):6387-6400
Research on Chemical Intermediates - Among the reactive oxygen species, the superoxide anion radical (O 2 ·? ) has a fundamental role in several biological functions. Consequently, its... 相似文献
20.
Faheem Amir Xuesong Li Max C. Gruschka Nathan D. Colley Lei Li Ruihan Li Houston R. Linder Scott A. Sell Jonathan C. Barnes 《Chemical science》2020,11(40):10910
Hydrogels that can respond to multiple external stimuli represent the next generation of advanced functional biomaterials. Here, a series of multimodal hydrogels were synthesized that can contract and expand reversibly over several cycles while changing their mechanical properties in response to blue and red light, as well as heat (∼50 °C). The light-responsive behavior was achieved through a photoredox-based mechanism consisting of photoinduced electron transfer from a zinc porphyrin photocatalyst in its excited state to oligoviologen-based macrocrosslinkers, both of which were integrated into the hydrogel polymer network during gel formation. Orthogonal thermoresponsive properties were also realized by introducing N-isopropyl acrylamide (NIPAM) monomer simultaneously with hydroxyethyl acrylate (HEA) in the pre-gel mixture to produce a statistical 60 : 40 HEA : NIPAM polymer network. The resultant hydrogel actuators – crosslinked with either a styrenated viologen dimer (2V4+-St) or hexamer (6V12+-St) – were exposed to red or blue light, or heat, for up to 5 h, and their rate of contraction, as well as the corresponding changes in their physical properties (i.e., stiffness, tensile strength, Young''s modulus, etc.), were measured. The combined application of blue light and heat to the 6V12+-St-based hydrogels was also demonstrated, resulting in hydrogels with more than two-fold faster contraction kinetics and dramatically enhanced mechanical robustness when fully contracted. We envision that the reported materials and the corresponding methods of remotely manipulating the dynamic hydrogels may serve as a useful blueprint for future adaptive materials used in biomedical applications.Orthogonal modes of activation in thermoresponsive hydrogel actuators using porphyrin-based visible light photoredox catalysis, viologen-based crosslinkers, and poly(N-isopropylacrylamide). 相似文献