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101.
Nafisa Gull Shahzad Maqsood Khan Muhammad Taqi Zahid Butt Saba Zia Syed Khalid Atif Islam Imran Sajid Rafi Ullah Khan Martin William King 《先进技术聚合物》2019,30(9):2414-2424
Hydrogel‐based drug delivery systems can leverage therapeutically favorable upshots of drug release and found clinical uses. Hydrogels offer temporal and spatial control over the release of different therapeutic agents. Because of their tailor made controllable degradability, physical properties, and ability to prevent the labile drugs from degradation, hydrogels provide platform on which diverse physicochemical interactions with entrapped drugs cause to control drug release. Herein, we report the fabrication of novel vinyltrimethoxy silane (VTMS) cross‐linked chitosan/polyvinyl pyrrolidone hydrogels. Swelling in distilled water in conjunction with different buffer and electrolyte solutions was performed to assess the swellability of hydrogels. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X‐ray diffraction (XRD) analysis were further conducted to investigate the possible interactions between components, thermal stability, and crystallinity of as‐prepared hybrid hydrogels, respectively. In vitro time‐dependent biodegradability, antimicrobial study, and cytotoxicity were also carried out to evaluate their extensive biocompatibility and cytotoxic behavior. More interestingly, in vitro drug release study allowed for the controlled release of cephradine. Therefore, this facile strategy developed the novel biocompatible and biodegradable hybrid hydrogels, which could significantly expand the scope of these hydrogels in other biomedical applications like scaffolds, skin regeneration, tissue engineering, etc. 相似文献
102.
Siddiqui Samia Nafady Ayman El-Sagher Hussein M. Al-Saeedi Sameerah I. Alsalme Ali M. Sirajuddin Talpur Farah N. Sherazi Syed Tufail H. Kalhoro Muhammad S. Shah Muhammad R. Shaikh Tayyaba Arain Munazza Bhargava Suresh K. 《Journal of Solid State Electrochemistry》2019,23(7):2073-2083
Journal of Solid State Electrochemistry - Bimetallic nanoparticles (BMNPs) have received considerable attention due to their distinctive properties when compared to the corresponding monometallic... 相似文献
103.
A. M. Shaikh 《Pramana》2008,71(4):663-672
Design and development of neutron detectors and R&D work in neutron radiography (NR) for non-destructive evaluation are important
parts of the neutron beam and allied research programme of Solid State Physics Division (SSPD) of Bhabha Atomic Research Centre
(BARC). The detectors fabricated in the division not only meet the in-house requirement of neutron spectrometers but also
the need of other divisions in BARC, Department of Atomic Energy units and some universities and research institutes in India
and abroad for a variety of applications. The NR facility set up by SSPD at Apsara reactor has been used for a variety of
applications in nuclear, aerospace, defense and metallurgical industries. The work done in the development of neutron detectors
and neutron radiography is reported in this article.
相似文献
104.
The powder diffractometer and Hi-Q diffractometer at Dhruva reactor make use of five identical 1-D position sensitive detectors (PSDs) to scan scattering angles in the range 3° to 140°. In order to improve the overall throughput of these spectrometers, it is planned to install a bank of 15 high-efficiency and high-resolution PSDs arranged in three layers with five PSDs in each layer. With each high pressure PSD (3He 10 bar + Kr 2 bar) showing the efficiency gain of 1.8 at 1.2 Å, detector bank is expected to show overall gain of 5.5 times the present detection efficiency and reduction in data collection time by equivalent factor. The 1-D PSDs are developed in batches of five, and are characterized so that all PSDs operate at uniform parameters such as position resolution, uniformity of efficiency and linearity of response. Position spectrum indicates the differential position resolution to be ~1 mm and integral position resolution to be 3–4 mm. Broadening of position spectrum at the extreme end of sensitive length of PSD is analysed using fine shift of the beam. Dependence of position resolution and dynamic range of output pulse on the input impedance of pre-amplifier is also presented. 相似文献
105.
The gravitational instability of an infinitely extending homogenous plasma endowed with several physical mechanisms, namely Hall currents, finite conductivity, ion viscosity and thermal conductivity is considered. The main result is that the various parameters play different physical roles in the perturbed problem. Jeans' criterion is analyzed in the framework of Tsallis' statistics for possible modifications due to the presence of nonextensive effects. A simple generalization of the Jeans' criterion is obtained and the standard values are obtained in the limiting case q=1, q being the nonextensive parameter. 相似文献
106.
Mohammad Sirousazar Homa Khadivi Saba Delir 《Journal of Macromolecular Science: Physics》2020,59(5):309-330
AbstractPolyvinyl alcohol and egg white bionanocomposite hydrogels loaded with montmorillonite clay were fabricated by a freezing-thawing technique. The bionanocomposite hydrogels showed an exfoliated morphology and they had a more interconnected and dense network as compared with the clay-free sample. The montmorillonite layers acted as multifunctional crosslinkers and the bionanocomposite hydrogels had nanoscale, slit-shaped pores. The swelling ratios of the bionanocomposite hydrogels were increased either by decreasing the content of incorporated montmorillonite or by increasing the pH of the swelling medium. It was found that the bionanocomposite hydrogels having a higher content of montmorillonite exhibited a slightly slower drying process with a longer drying duration. Using the Ritger-Peppas model, it was shown that the swelling and drying mechanisms for all bionanocomposite hydrogels were non-Fickian diffusion. According to the Peppas-Sahlin model, it was found that the absorption of the swelling agent molecules during the swelling process and also the removal of water molecules during the drying process in the early stages of the processes occurred mostly due to their diffusion. At higher swelling or drying times, the contribution of the relaxation (for swelling) and shrinkage (for drying) of the polyvinyl alcohol polymeric chains and egg white protein chains was increased. 相似文献
107.
Seema Yadav Sriparna Ray Ajeet Singh Shaikh M. Mobin Tapta Kanchan Roy Chandrakanta Dash 《应用有机金属化学》2020,34(11):e5942
Dinuclear gold(I)-N-heterocyclic carbene complexes were developed for the hydrohydrazidation of terminal alkynes. The gold(I)-N-heterocyclic carbene complexes 2a-2b were synthesized in good yields from silver complexes synthesized in situ, which in turn were obtained from the corresponding imidazolium salts with Ag2O in dichloromethane as a solvent. The new air-stable gold(I)-NHC complexes, 2a - 2b, were characterized using NMR spectroscopy, elemental analysis, infrared, and mass spectroscopy studies. The gold(I) complex 2a was characterized using X-ray crystallography. Bis-N-heterocyclic carbene–based gold(I) complexes 2a - 2b exhibited excellent catalytic activities for hydrohydrazidation of terminal alkynes yielding acylhydrazone derivatives. The working catalytic system can be used in gram-scale synthesis. In addition, the catalytic reaction mechanism of the hydrohydrazidation of terminal alkynes by gold(I)-NHC complex was studied in detail using density functional theory. 相似文献
108.
An efficient,mild and selective Ullmann‐type N‐arylation of indoles catalysed by Pd immobilized on amidoxime‐functionalized mesoporous SBA‐15 as heterogeneous and recyclable nanocatalyst
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A wide range of N‐arylated indoles were selectively synthesized through intermolecular C(aryl)? N bond formation from the corresponding aryl iodides and indoles through Ullmann‐type coupling reactions in the presence of a catalytic amount of Pd immobilized on amidoxime‐functionalized mesoporous SBA‐15 (SBA‐15/AO/Pd(0)) under mild reaction conditions. These cross‐coupled products were obtained in excellent yields under mild conditions at extremely low palladium loading (ca 0.3 mol%), and the heterogeneous catalyst can be readily recovered by simple filtration and reused seven times with loss in its activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
109.
Saba Hemmati Mohammad Yousefi Mirmehdi Hashemi Salehi Mahdis Amiri Malak Hekmati 《应用有机金属化学》2020,34(8):e5653
This paper develops a green method for in situ decorated of palladium nanoparticles over Fe3O4 nanoparticles, by utilizing Strawberry fruit extract and ultrasound irradiations, with no use of any toxic reducing agent. The structure's characterization is represented via diverse analytical methods such as FT-IR, FE-SEM, TEM, WDX, ICP, EDS and XXPS. Catalytic efficiency of magnetic Fe3O4@Strawberry/Pd nanocatalyst is investigated in production of different biphenyls with good turnover frequencies (TOF) and turnover numbers (TON) through Suzuki coupling reactions. Furthermore, the catalyst could be recovered and reused 7 runs without considerable palladium leaching or alteration in its performance. 相似文献
110.
Journal of Experimental and Theoretical Physics - This paper is devoted to construction of generalized ghost dark energy f(G) model by using correspondence scheme for both interacting and... 相似文献