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排序方式: 共有804条查询结果,搜索用时 15 毫秒
41.
Nema Ankita Bano Mustri Rai Mansi Shrivastava Kavya Dangi Sambhavna Singh Khan Farid 《Journal of Porous Materials》2022,29(2):459-471
Journal of Porous Materials - Silver monoliths using non-ionic surfactant Triton X-102 as reducing agent with and without additives such as Dextran and Ludox (SiNPs) were synthesized by modified... 相似文献
42.
Adil Farooq Arfa Iqbal Nosheen Fatima Rana Misha Fatima Tuba Maryam Farhat Batool Zahra Rehman Farid Menaa Shabia Azhar Afrah Nawaz Faheem Amin Zuhair M. Mohammedsaleh Salma Saleh Alrdahe 《International journal of molecular sciences》2022,23(6)
Chronic liver disease (CLD) is a global threat to the human population, with manifestations resulting from alcohol-related liver disease (ALD) and non-alcohol fatty liver disease (NAFLD). NAFLD, if not treated, may progress to non-alcoholic steatohepatitis (NASH). Furthermore, inflammation leads to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Vitexin, a natural flavonoid, has been recently reported for inhibiting NAFLD. It is a lipogenesis inhibitor and activates lipolysis and fatty acid oxidation. In addition, owing to its antioxidant properties, it appeared as a hepatoprotective candidate. However, it exhibits low bioavailability and low efficacy due to its hydrophobic nature. A novel rat model for liver cirrhosis was developed by CCL4/Urethane co-administration. Vitexin encapsulated liposomes were synthesized by the ‘thin-film hydration’ method. Polyethylene glycol (PEG) was coated on liposomes to enhance stability and stealth effect. The diseased rats were then treated with vitexin and PEGylated vitexin liposomes, administered intravenously and orally. Results ascertained the liposomal encapsulation of vitexin and subsequent PEG coating to be a substantial strategy for treating liver cirrhosis through oral drug delivery. 相似文献
43.
A tire thread formulation for heavy‐duty trucks containing SBR/BR rubber blend and varying proportions of silica/clay fillers including a silane‐coupling agent have been investigated. The various mixes were compounded in a Banbury ‘O’ mixer and vulcanized using the EV‐system. Silica/clay (80/0) served as the control mix. The oscillating disc rheometer (ODR) was used in determination of cure characteristics. Substitution of silica (80 phr) with china clay up to 40 phr increased the cure rate of the rubber blend mixes as well as their maximum torque level (Tmax). Tmax was observed to be highest at a filler blend ratio of 40/40 phr. Synergism between silica and clay at this filler blend mixture is suggested to be responsible for the observation. The heat buildup was reduced from 43 to 20°C as the clay content increased. Results also showed that the rubber blend compound containing silica/clay (60/20) filler blend in the stated ratio exhibited the best balance of properties in the critical parameters such as the absolute torque level (69.5 dNm), heat buildup (39°C), and abrasion resistance (0.574 mg.loss/1,000 rev). The rate of depreciation of abrasion resistance of rubber blend compound as the clay content increased was found to be 0.035 mg loss/1,000 rev as silica is substituted with one part of china clay phr. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1024–1028, 2004 相似文献
44.
Farid Jamali-Sheini Ramin Yousefi M.R. Mahmoudian Nabeel Ali Bakr Abdolhossein Sa΄aedi Nay Ming Huang 《Ceramics International》2014
Te-doped ZnO nanostructures were synthesized by an annealing (vapor–solid) process under ambient conditions, and characterized in terms of their morphological, structural, compositional and optical properties. The structural and morphological characterizations revealed that the synthesized nanostructures were well-defined multipods, needles and spherical particles, and possessed well-crystalline ZnO wurtzite hexagonal phase. Also, in the X-ray diffraction studies, the presence of a shift in the peak positions towards a lower angle, and a decrease in the intensity, with an increase in the Te concentration, as compared to the undoped ZnO, were observed. The chemical composition confirmed the presence of Te, in the case of multipod and needle morphologies. The effect of doping on the crystalline quality and optical properties was also investigated, by using photoluminescence (PL) and Raman spectrometers. The Raman results demonstrated that the doped ZnO nanostructures had a lower crystalline quality than the undoped ZnO. Moreover, the PL results showed a decrease in the band gap for the doped ZnO nanostructures, in comparison to the undoped ZnO. A possible growth mechanism was also proposed. 相似文献
45.
Elaheh Kazemi-Khasragh Farid Bahari-Sambran Seyed Mohammad Hossein Siadati Reza Eslami-Farsani Shabnam Arbab Chirani 《应用聚合物科学杂志》2019,136(39):47986
Possessing unique designs and properties absent in conventional materials, nanocomposites have made a remarkable imprint in science and technology. This is particularly true regarding the polymer matrix composites when they are further reinforced with nanoparticles. In this study, the effects of different weight percentages (0, 0.1, 0.2, 0.3, 0.4, and 0.5) of surface-modified graphene nanoplatelets (GNPs) on the microhardness and wear properties of basalt fibers/epoxy composites were investigated. The GNPs were surface modified by silane, and the composites were made by the hand lay-up method. The wear tests were conducted under two different loads of 20 and 40 N. The best wear properties were achieved at 0.3 wt % GNPs as a result of the GNPs' self-lubrication property and the formation of a stable transfer/lubricating film at the pin and disk interface. Moreover, the friction coefficient was lower at the higher normal load of 40 N. The microscopic studies by FESEM and SEM showed that the presence of GNPs up to 0.3 wt % led to the stability of the transfer/lubricating film by enhancing the adhesion of the basalt fibers to the epoxy resin. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47986. 相似文献
46.
Farid H. Abed 《Mechanics of Time-Dependent Materials》2010,14(4):329-345
A constitutive relation is presented in this paper to describe the plastic behavior of ferritic steel over a broad range of
temperatures and strain rates. The thermo-mechanical behavior of high strength low alloy (HSLA-65) and DH-63 naval structural
steels is considered in this study at strains over 40%. The temperatures and strain rates are considered in the range where
dynamic strain aging is not effective. The concept of thermal activation analysis as well as the dislocation interaction mechanism
is used in developing the flow model for both the isothermal and adiabatic viscoplastic deformation. The flow stresses of
the two steels are very sensitive to temperature and strain rate, the yield stresses increase with decreasing temperatures
and increasing strain rates. That is, the thermal flow stress is mainly captured by the yield stresses while the hardening
stresses are totally pertained to the athermal component of the flow stress. The proposed constitutive model predicts results
that compare very well with the measured ones at initial temperature range of 77 K to 1000 K and strain rates between 0.001 s−1 and 8500 s−1 for both steels. 相似文献
47.
Farid C. Christo 《Renewable Energy》2012,39(1):356-366
This study reports on numerical predictions of velocity and pressure fields, and dust particles trajectories in steady and unsteady flows around a full-scale paraboloidal solar dish. Calculations are performed for three wind speeds of 4.16, 9.72, and 15.2 m s−1, and dish pitch angles from 0° to 180°. The flow field structure, lift and drag coefficients are calculated for each flow configuration. Using the predicted mean flow velocity field, analytical expressions for the aerodynamic coefficients, as a function of the pitch angle, are developed. The unsteady-state flow is characterised by formation of stable vortices behind the dish for most flow configurations, except at 60° and 150° pitch angles. At these angles vortex-shedding occurred with a strong flow oscillation extending downstream the dish. The calculations of dust particles trajectories provide a qualitative assessment of the deposition rate, dish orientation, and surface locations where dust accumulation is most likely to occur. The study also presents an initial assessment of the effectiveness of various windbreaks installed upstream of the dish in reducing aerodynamics drag. 相似文献
48.
49.
Ahmed Reda Yeddou Boubakeur Nadjemi Farid Halet Aïssa Ould-Dris Richard Capart 《Minerals Engineering》2010,23(1):32-39
This work is dedicated to the removal of the very toxic free cyanide from aqueous solution by oxidation with hydrogen peroxide H2O2 in the presence of activated carbon prepared from olive stones. Effects of the initial molar ratio [H2O2]0/[CN?]0, the initial cyanide concentration, the activated carbon concentration and the temperature on cyanide removal have been examined. The removal of free cyanide in absence of activated carbon showed very slow kinetics. The presence of activated carbon has increased the reaction rate showing thus a catalytic activity. The kinetics of cyanide removal has been found to be of pseudo-first-order with respect to cyanide and the rate constants have been determined for different values of the aforementioned parameters. The apparent activation energy has been determined from tests carried out at three different temperatures. It was found equal to 46.2 kJ/mol in the presence of activated carbon, which is about half of the 82.7 kJ/mol found for the oxidation in absence of the activated carbon.This process can be interesting for the cyanide removal from processed solutions because it does not use soluble metal catalyst and it consumes only hydrogen peroxide as chemical product. 相似文献
50.
Influence of the deposition duration and electrolyte concentration on the structural and morphological features of the ZnO thin films, grown by cathodic electrodeposition on zinc substrate followed by annealing in air at 400 °C, have been investigated. The surface morphology of the as-synthesized films shows two distinct features, presence of ‘2-dimensional nanosheets’ on the area near the electrolyte-air interface and ‘granular’ nanostructures, below the interface region. However, upon annealing, the formation of ZnO nanowires, possessing length of several microns and diameter less than 20 nm, on the entire substrate is observed. The X-ray and selected area electron diffraction patterns clearly confirm the polycrystalline nature of the ZnO nanowires. 相似文献