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41.
Siguang Chen Rangari Vijaya Kumar Aharon Gedanken Arie Zaban 《Israel journal of chemistry》2001,41(1):51-54
A composite material made of zinc oxide and polyvinyl alcohol was prepared by a sonochemical method. Annealing of the composite under air removed the polymer, leaving porous spheres of ZnO. This change was accompanied by a change of the surface area from 2 m2/g to 34 m2/g. The porous ZnO particles were used as the electrode material for dye-sensitized solar cells (DSSCs). It was tested by forming a film of the doped porous ZnO on a conductive glass support. The performance of the solar cell is reported. 相似文献
42.
Fatih Kalkan Sai Kranthi Vanga Ramesh Murugesan Valerie Orsat Vijaya Raghavan 《Drying Technology》2017,35(5):527-533
This study was performed to investigate the influence of air inlet temperature (AIT) on the microencapsulation of hazelnut oil by spray drying. Encapsulated powders were analyzed for moisture content, powder yield, surface oil, encapsulation efficiency (EE), bulk density, and particle morphology. The obtained results demonstrated that moisture content, surface oil, and bulk density decreased by 37.8, 27.5, and 33%, respectively as AIT increased from 140 to 220°C. However, powder yield and encapsulation efficiency increased considerably with the rise in AIT. Higher EEs of about 75–80% were observed in this study. 相似文献
43.
A new polymer electrolyte based on the biopolymer Agar‐Agar doped with ammonium thiocyanate (NH4SCN) has been prepared and characterized by FTIR analysis, X‐ray diffraction measurements, AC impedance spectroscopy, transference number measurements, and DSC analysis. The Fourier transform infrared analysis confirms the complex formation between agar and NH4SCN. The amorphous nature of the polymer electrolyte has been revealed from X‐ray diffraction analysis. The highest ionic conductivity has been observed for the sample of composition 1:1 between Agar and NH4SCN. As a function of temperature, the ionic conductivity of this sample exhibits Arrhenius behavior increasing from 1.03 × 10?3 S cm?1 at ambient temperature to 3.16 × 10?3 S cm?1 at 343 K. The transference number has been estimated by the dc polarization method, and it has been proven that the conducting species are predominantly cations. Using the highest conductivity polymer electrolyte, solid state electrochemical cell has been fabricated and cell parameters are reported. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44702. 相似文献
44.
This study represents the application of nanozeolite NaX (NZX) synthesized by hydrothermal treatment without addition of any expensive structure directing agent for the highly effectual adsorption of biochanin A from aqueous solution. The characteristics and surface morphology of NZX were determined using FT-IR, SEM, TEM, BET, and XRD. The adsorption performance of NZX was analyzed at different conditions such as temperature, pH, contact time, adsorbent dose, and initial adsorbate concentration. The adsorption mechanism was well verified by pseudo-second-order kinetic and Redlich–Peterson isotherm models. The thermodynamic parameters revealed that the removal process was exothermic and spontaneous. 相似文献
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47.
Vijaya L. Manugula G. Madhusudhan Reddy E. Rajendra Kumar K. Bhanu Sankara Rao 《Science & Technology of Welding & Joining》2018,23(8):666-676
Full penetration friction stir welding was conducted on 12?mm thick reduced activation ferritic–martensitic steel at tool rotational speeds of 500 and 900?rev?min?1. Comparator welds at 500?rev?min?1 were also produced in 6?mm thick reduced activation ferritic–martensitic steel plate to evaluate section thickness effects. Increase in section thickness led to an increase in heat input, which strongly influenced the microstructure evolution in stir zone (SZ), thermo-mechanical affected zone and the overall hardness in the SZ of this steel. In the as-welded condition, the base metal microstructure was significantly altered and resulted in carbide-free grain boundaries. The desirable microstructure and mechanical properties were achieved by subjecting the as-welded joints to appropriate post-weld heat treatments. 相似文献
48.
Vijaya Karoor Derek Strassheim Timothy Sullivan Alexander Verin Nagavedi S. Umapathy Edward C. Dempsey Daniel N. Frank Kurt R. Stenmark Evgenia Gerasimovskaya 《International journal of molecular sciences》2021,22(18)
Pulmonary hypertension (PH) is a progressive cardiovascular disorder in which local vascular inflammation leads to increased pulmonary vascular remodeling and ultimately to right heart failure. The HDAC inhibitor butyrate, a product of microbial fermentation, is protective in inflammatory intestinal diseases, but little is known regarding its effect on extraintestinal diseases, such as PH. In this study, we tested the hypothesis that butyrate is protective in a Sprague–Dawley (SD) rat model of hypoxic PH. Treatment with butyrate (220 mg/kg intake) prevented hypoxia-induced right ventricular hypertrophy (RVH), hypoxia-induced increases in right ventricular systolic pressure (RVSP), pulmonary vascular remodeling, and permeability. A reversal effect of butyrate (2200 mg/kg intake) was observed on elevated RVH. Butyrate treatment also increased the acetylation of histone H3, 25–34 kDa, and 34–50 kDa proteins in the total lung lysates of butyrate-treated animals. In addition, butyrate decreased hypoxia-induced accumulation of alveolar (mostly CD68+) and interstitial (CD68+ and CD163+) lung macrophages. Analysis of cytokine profiles in lung tissue lysates showed a hypoxia-induced upregulation of TIMP-1, CINC-1, and Fractalkine and downregulation of soluble ICAM (sICAM). The expression of Fractalkine and VEGFα, but not CINC-1, TIMP-1, and sICAM was downregulated by butyrate. In rat microvascular endothelial cells (RMVEC), butyrate (1 mM, 2 and 24 h) exhibited a protective effect against TNFα- and LPS-induced barrier disruption. Butyrate (1 mM, 24 h) also upregulated tight junctional proteins (occludin, cingulin, claudin-1) and increased the acetylation of histone H3 but not α-tubulin. These findings provide evidence of the protective effect of butyrate on hypoxic PH and suggest its potential use as a complementary treatment for PH and other cardiovascular diseases. 相似文献
49.
Ganta Kiran Kumar Jeedi Venkata Ramana Katrapally Vijaya Kumar Yalla Mallaiah Emmadi Laxmi Narsaiah 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(8):3430-3440
Journal of Inorganic and Organometallic Polymers and Materials - Nanocomposite polymer electrolyte (NCPE) films based on a blend of two polymers poly (ethylene oxide) (PEO) and poly (vinylidene... 相似文献
50.
Silicon - In recent times, the study on machining characteristics of combined (hybrid) fiber polymer composites has drawn a remarkable research attention because of its emerging industrial... 相似文献