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991.
Wireless Personal Communications - In this paper, a triangular complementary split ring resonator (TCSRR) based compact metamaterial antenna for multiband operation is presented. TCSRR is used to... 相似文献
992.
Ziyaad Mohamed Venkata D.B.C. Dasireddy Sooboo Singh Holger B. Friedrich 《International Journal of Hydrogen Energy》2018,43(49):22291-22302
CO oxidation and methanation over Ru-TiO2 and Ru-ZrO2 catalysts were investigated for CO removal for applications in proton exchange membrane fuel cells. The catalysts were synthesised by the deposition precipitation method at a pH of 7–7.5 for better interactions between the support and the active Ru metal. Various characterization experiments such as TPR, XPS, FTIR-CO, CO chemisorption and HRTEM were conducted to better understand the physio-chemical properties of Ru on the supports. Both catalysts showed excellent activity for the total oxidation of CO, however, with the addition of H2, the catalysts activity to CO oxidation decreased significantly. Higher temperatures for the preferential oxidation reaction indicated that the Ru catalysts not only oxidize CO, but hydrogenate it as well. Furthermore, H2 oxidation was favoured over the catalysts. Hydrogenation of CO over these catalysts gave high CO conversion and selectivity towards CH4. Both the catalysts showed similar activity across the temperature range screened and gave maximum CO conversions of 99.9% from 240 °C onwards, with 99.9% selectivity towards CH4. The catalysts also showed good stability in the reaction and the similarities in the catalytic activity of these were attributed to the well-dispersed Ru metal over the supports. The Ru catalysts effectively reduced CO concentrations in the reformate gas to less than 10 ppm, as is required for practical applications. 相似文献
993.
Kishore Reddy Venkata Thappeta Li Na Zhao Choy Eng Nge Sharon Crasta Chung Yan Leong Veronica Ng Yoganathan Kanagasundaram Hao Fan Siew Bee Ng 《International journal of molecular sciences》2020,21(22)
Sortase A (SrtA) is a membrane-associated enzyme that anchors surface-exposed proteins to the cell wall envelope of Gram-positive bacteria such as Staphylococcus aureus. As SrtA is essential for Gram-positive bacterial pathogenesis but dispensable for microbial growth or viability, SrtA is considered a favorable target for the enhancement of novel anti-infective drugs that aim to interfere with key bacterial virulence mechanisms, such as biofilm formation, without developing drug resistance. Here, we used virtual screening to search an in-house natural compound library and identified two natural compounds, N1287 (Skyrin) and N2576 ((4,5-dichloro-1H-pyrrol-2-yl)-[2,4-dihydroxy-3-(4-methyl-pentyl)-phenyl]-methanone) that inhibited the enzymatic activity of SrtA. These compounds also significantly reduced the growth of S. aureus but possessed moderate mammalian toxicity. Furthermore, S. aureus strains treated with these compounds exhibited reduction in adherence to host fibrinogen, as well as biofilm formation. Hence, these compounds may represent an anti-infective therapy without the side effects of antibiotics. 相似文献
994.
M. B. Tahir Ghulam Nabi A. Hassan T. Iqbal H. Kiran A. Majid 《Journal of Inorganic and Organometallic Polymers and Materials》2018,28(3):738-745
Photocatalytic degradation is an ambitious and cost effective technique used for decontamination and sanitization of the waste polluted water of environment. Hydrothermal method is used to synthesis the carbon coupled WO3 nanoparticles with different concentrations of carbon (0.0, 0.2, 0.5, 1.0 and 2.0%) from precursor Na2WO4·2H2O with glucose and nitric acid. Synthesized nanoparticles were characterized by SEM, EDX, XRD, UV–Vis, and PL to study morphology, and particle size, composition, structural and optical properties, respectively. SEM revealed that morphology of the carbon coupled WO3 nanoparticles becomes spherical by increasing amount of coupled carbon atoms. The average grain size of the carbon doped nanoparticles is found to be 15–20 nm. Furthermore, size of nanoparticles affect the band gap of synthesized nanoparticles as well. It has also been observed that carbon coupled WO3 nanoparticles effectively take part in photo degradation due to reduction of electron–hole recombination rate. 相似文献
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997.
Metabolic syndrome is characterized by hypertension; hyperglycemia; hypertriglyceridemia; reduced high-density lipoprotein cholesterol levels and abdominal obesity. Abundant data suggest that, compared with other people, patients meeting these diagnostic criteria have a greater risk of having substantial clinical consequences, the two most prominent of which are the development of diabetes mellitus and coronary heart disease. The metabolic syndrome is a health issue of epidemic proportions. Its prevalence in the world continues to increase, hand in hand with that of obesity. Protein, on the other hand, is the foundation of cell-building, especially in muscle tissue. The body needs protein to build not only muscle cells, but the cells of major organs, skin and red blood cells. For people with metabolic syndrome, one of the other functions of protein is to slow down the absorption of carbohydrates. When proteins are consumed with carbohydrates, it takes longer for the digestive system to break down that meal. This means that the sugar created from those carbohydrates is released at a slower rate, preventing spikes in both blood sugar and insulin. As the understanding of the metabolic syndrome evolves, it is likely that more comprehensive therapeutic options will become available. 相似文献
998.
Nanofiltration (NF) is a membrane-based separation process having significant potential for the treatment of industrial effluents to enable water reuse. It has the ability to remove low molecular weight trace contaminants from water, which cannot be separated by conventional treatment methods. In the present investigation, a thin film composite polyamide membrane was synthesized by interfacial polymerization technique and evaluated for the treatment of biscuit industrial effluent. The synthesized membrane was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy to elucidate structure and intermolecular interactions, crystallinity, thermal stability and cross-sectional morphology, respectively. The influence of operating parameters such as feed pressure 0–21 kg/cm2 and total dissolved solids (TDS) of 3160 ppm on water flux and impurity rejection was determined. An average flux of 11.63 L/m2 h was obtained at a constant pressure of 21 kg/cm2. The TDS, chemical oxygen demand (COD), and biochemical oxygen demand (BOD) rejections were found to be 53.62, 80, and 74%, respectively, at a water recovery of 65%. A statistical mechanical model was used to validate the experimental data. Based on this study, a detailed economic estimation for processing biscuit effluent of 1 m3/h feed capacity using commercial NF system is presented. The study revealed that the synthesized NF membrane could be an effective alternative for the treatment of various industrial effluents as well as to reduce the load on reverse osmosis process for desalination of seawater and effluent treatment through high degree of COD and BOD separation. 相似文献
999.
Sarada Prasanna Mallick Dheerendra Kumar Suman Bhisham Narayan Singh Pradeep Srivastava Nadeem Siddiqui Venkata Rajesh Yella 《Polymer-Plastics Technology and Engineering》2020,59(9):911-927
ABSTRACTHydrogel is a macromolecular gel constructed of a network of cross-linked polymer chains. Hydrogels are class of materials that can be tuned toward the subjected stimuli and can be modified to imitate the extracellular environment of the body which makes hydrogel worthy of being used in tissue regeneration, drug delivery, and other fields of science. Hydrogels offer excellent potential as oral therapeutic systems due to inherent biocompatibility, and biodegradability. Hydrogels are having various tissue engineering and drug delivery application due to its high loading with ensured molecule efficacy, high encapsulation, variable release profile, stable, and inexpensive. 相似文献