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931.
Aswin V. Pramod Kumar Pooja Singh Anurag Gupta S. Rayaprol Anjana Dogra 《Journal of Materials Science》2015,50(1):366-373
We report investigations on polycrystalline LaCo1?x Al x O3 (x = 0–0.9) bulk samples. The solid state synthesized samples showed a coexistence of rhombohedral and monoclinic phases in the intermediate concentrations (0.2 ≤ x ≤ 0.5) and pure rhombohedral phase otherwise. The observed effect of Al doping on dc transport has been analysed on the basis of small polaron hopping mechanism. The magnetisation results presented give evidence of weak ferromagnetism and anomalous temperature dependence of coercivity which we associate to the canting of the localised high-spin Co(III) and anti-symmetric exchange interactions at low temperatures. 相似文献
932.
Bhaskar Daravath Sateesh Kumar Vemula 《Drug development and industrial pharmacy》2015,41(8):1254-1262
Context: Development of solid dispersions is to improve the therapeutic efficacy by increasing the drug solubility, dissolution rate, bioavailability as well as to attain rapid onset of action.Objective: The present research deals with the development of solid dispersions of flurbiprofen which is poorly water soluble to improve the solubility and dissolution rate using gelucires.Materials and methods: In this study, solid dispersions were prepared following solvent evaporation method using gelucire 44/14 and gelucire 50/13 as carriers in different ratios. Then the formulations were evaluated for different physical parameters, solubility studies, DSC, FTIR studies and in vitro dissolution studies to select the best formulation that shows rapid dissolution rate and finally subjected to pharmacokinetic studies.Results and discussion: From the in vitro dissolution study, formulation F3 showed the better improvement in solubility and dissolution rate. From the pharmacokinetic evaluation, the control tablets produced peak plasma concentration (Cmax) of 9140.84?±?614.36?ng/ml at 3?h Tmax and solid dispersion tablets showed Cmax?=?11?445.46?±?149.23?ng/ml at 2?h Tmax. The area under the curve for the control and solid dispersion tablets was 31?495.16?±?619.92 and 43?126.52?±?688.89?ng h/ml and the mean resident time was 3.99 and 3.68?h, respectively.Conclusion: From the above results, it is concluded that the formulation of gelucire 44/14 solid dispersions is able to improve the solubility, dissolution rate as well as the absorption rate of flurbiprofen than pure form of drug. 相似文献
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936.
Study on crosslinked gelatin–montmorillonite nanoparticles for controlled drug delivery applications
Mandip Sarmah Nibedita Banik Anowar Hussain Anand Ramteke Hemanta K. Sharma Tarun K. Maji 《Journal of Materials Science》2015,50(22):7303-7313
Gelatin, because of its biodegradability and ecofriendly nature, has been the best choice for controlled release applications. Montmorillonite (MMT) clay shows a very important role in controlling drug delivery. Hence, an attempt was made in this work to prepare gelatin–MMT nanoparticles by desolvation method using acetone as precipitating agent, glutaraldehyde (GA) as crosslinking agent, and water as reaction media for controlled delivery of isoniazid, a drug for tuberculosis. Characterization of the MMT and isoniazid-loaded gelatin–MMT nanoparticles was carried out using Fourier transform infrared spectroscopy, X-ray diffraction study, scanning electron microscopy study, and transmission electron microscopy study. The effect of MMT on gelatin nanoparticles was evaluated in terms of water uptake studies, and subsequently to the release of isoniazid drug in buffer solution at pH 1.2 (gastric pH) and pH 7.4 (intestinal pH). Swelling experiment indicated that the gelatin nanoparticles were very sensitive to the pH environment. The release profile of drug was studied by a UV–Visible spectrophotometer. Cytotoxicity study revealed that MMT-containing nanoparticles showed less cytotoxicity than MMT-free nanoparticles. 相似文献
937.
Kumar Manjesh Alok Anupam Das Manas 《Journal of Mechanical Science and Technology》2021,35(11):5151-5159
Journal of Mechanical Science and Technology - In this article, a new flow restrictor is utilized in the magnetorheological miniature gear-profile polishing (MRMGPP) method to ensure a consistent... 相似文献
938.
Chemisorbed reaction films (CRFs) were prepared by using iron (Fe) particles (100–200 mess size) and thio (sulfur) derivatives of ethyl octadecenoate and methyl 12‐hydroxy octadecenoate in the light viscosity paraffin liquid medium. The reaction was conducted in a simulated condition of tribo‐chemical situation. CRFs were obtained in solid amorphous phase. The CRFs were examined for elemental composition and layer analysis using C‐H‐N‐O‐S analyzer and Fourier transform infrared spectroscopy micro‐reflectance absorption spectroscopic technique. Further, the CRFs were isolated into organic solvent soluble fractions using polar solvents of increasing polar strength. Their elemental analyses were studied, and chemical constitutions were known. Friction coefficient and wear scar diameter were evaluated by high frequency reciprocating rig, PLINT TE‐77 machine. Thermal stability was studied using thermogravimetric analysis technique in nitrogen environment. These studies inferred that CRFs appeared varying in its composition, luster, phase, chemical structure and thermal stability. Nonetheless, these were also found anomalous in elemental distribution throughout the layer structure of the CRFs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
939.
Brajendra Kumar Singh Jeremy Coulter Mohammad Abdul Ghani Sayani Syed M. Sami Mohammad Khalid Kemal E. Tepe 《The International journal of environmental studies》2013,70(5):765-776
Communication systems are needed to integrate generated power from wind farms with the electrical grid. This paper provides a comprehensive review of available communication technologies, protocols and objectives related to wind energy and electrical grid integration. This paper summarizes the communication system solutions for wind generation. A major obstacle is an absence of unified communication architectures and standards. 相似文献
940.
India is one of the largest growing economies in the world. It has a GDP of 2487.94 billion US dollars as of 2017. Around 61.297% of power generation is by utilising abundantly available lignite blended with imported coal. India is slowly cutting out its demand for imported coal from other countries. It has built its own lignite-based power plant to overcome the need of imported coal. The impact on cost of electricity (COE) and net power output (NPO) after retrofitting carbon capture and storage (CCS) over a lignite-based power plant of India is analysed. In this paper, a feasibility study is carried out for NLC India Ltd Barsingsar power plant by retrofitting CCS. The results obtained from the Integrated Environmental Control Model (IECM) Software are positively strong enough to encourage CCS implementation. Various strategies for utilising the CO2 capture and carbon storage sites are suggested. 相似文献