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991.
In this paper an isotherm regularity has been introduced for gases and liquids based on intermolecular potential energy. The experimental data has been used to demonstrate the validity of the regularity. A non-linearity relationship exists between (Z ? 1)v3 and ρ for all isotherms of liquids and gases. The basis for this regularity is intermolecular potential which is a modified Lennard–Jones potential (9, 6, 3) for repulsive, dispersion, dipole–dipole and longer-ranged interactions. The isotherm regularity is equivalent to a virial-like EOS for which the parameters of the isotherm form the corresponding second, third and fourth virial-like coefficients. The equation of state is simple and ready to use. The parameters of equation of state are determined by fitting isothermal regularity to experimental data. The new equation of state provides excellent results in homogenous gas and homogeneous liquids region to very high pressures while its predictions in gas-liquid transition have more deviations. Densities of 1828 data points of 21 components have been calculated over the entire range of data with a maximum pressure of 1000 MPa. The average absolute deviation between calculated and experimental densities for gases, liquids and gas-liquid transition region are 0.06%, 0.03% and 0.90%, respectively.  相似文献   
992.
Overproduction of apelin in obesity could be one of the last protective defenses before type 2 diabetes develops. To summarize the existing evidence on the association between dietary intake and apelin gene expression and concentration. We systematically searched MEDLINE, EMBASE, and google scholar and hand-searched bibliographies, including peer-reviewed articles with English abstracts, without restriction in publication date, updated until 21 February 2016 that reported the association between dietary intake and apelin gene expression or concentration. From a total of 1075 articles, we identified 12 relevant studies. There were 6 clinical trials in human and 6 studies in animals. Overall, two of three studies conducted in humans showed that calorie-restriction diet in obese subjects decreases apelin concentration. Five animal studies reported that higher intake of fatty acids and eicosapentaenoic acid (EPA) increased apelin expression and concentration. Given the paucity of data available, the heterogeneity of study designs used, and exposures tested, no quantitative meta-analysis was justified. Based on human studies, hypocaloric diet can reduce apelin concentration in obese individuals. In addition, higher intakes of total fatty acids and EPA may increase apelin gene expression and concentration.  相似文献   
993.
In recent study, 15 taxa of family Poaceae from Dera Ghazi Khan were investigated for morphological characterization of seeds. Scanning electron microscopy (SEM) was utilized to study morphological features of grass seeds. Moreover, economic importance of studied taxa has been discussed in present research. Grass seeds or caryopsis were collected in their mature state from different areas of Dera Ghazi Khan. Collected caryopses were subjected to SEM to investigate surface sculpture, epidermal cell shape, and cell wall patterns. Caryopsis shape observed was elliptic to oval. Also, the morphology of plant is being investigated. Cell wall pattern observed was straight and wavy. Surface sculpturing varies from smooth to reticulate. Epidermal cell shape was either wavy or irregular. Hilum position is terminal in all species. Epidermal cell structure and cell wall pattern was not observable in some species. Major variations among studied taxa were observed in terms of seed surface pattern. Five types of caryopsis surface pattern were observed namely, striate, smooth, reticulate, papillate, and granulate. Investigated taxa illustrated variations in terms of studied morphological features. Utilization of SEM has been proved very helpful in exploring seed morphological features. These observed features can aid in delimitation and identification of various grass taxa. Recent research recommends the utilization of SEM for caryopsis morphology to solve the identification issue of problematic grass genera.  相似文献   
994.
A territorial-based filtering algorithm (TBFA) is proposed as an integration tool in a multi-level design optimization methodology. The design evaluation burden is split between low- and high-cost levels in order to properly balance the cost and required accuracy in different design stages, based on the characteristics and requirements of the case at hand. TBFA is in charge of connecting those levels by selecting a given number of geometrically different promising solutions from the low-cost level to be evaluated in the high-cost level. Two test case studies, a Francis runner and a transonic fan rotor, have demonstrated the robustness and functionality of TBFA in real industrial optimization problems.  相似文献   
995.
Material handling (including digging) is one of the most energy-intensive processes in mining. Operators’ skills and practices are known to be some of the major factors that affect energy efficiency of digging operations. Improving operators’ skills through training is an inexpensive and effective method to improve energy efficiency. The method proposed in this work uses data collected by monitoring systems on digging equipment to detect the monitored parameters that lead to differences in energy efficiency of operators (responsible parameters). After data extraction, removing the outliers, and identifying the operators with sufficient working hours, correlation analysis can be used to find parameters that are correlated with energy efficiency. Regression analysis on pairs of operators is then used to detect responsible parameters. Random sampling is used to overcome missing data issues in the analysis. This statistics-based method is simple and adequately accounts for the high variability in data collected from these monitoring systems. The proposed method was illustrated using data collected on five operators working on a 64-m3 (85 yd3) Bucyrus-Erie 1570w dragline. The case study results show that dump height and engagement/disengagement position of the bucket are the most likely parameters to cause differences between energy efficiency of these operators. On the other hand, cycle time, payload, and swing in time are least likely to influence differences in operator energy efficiency.  相似文献   
996.
Kianfar  Ehsan  Shirshahi  Maryam  Kianfar  Farangis  Kianfar  Farshid 《SILICON》2018,10(6):2617-2625
Silicon - An Artificial Neural Network (ANN) model is presented for the Simultaneous prediction of density, viscosity and electrical conductivity of pyridinium-based hydrophobic ionic liquids. Data...  相似文献   
997.
998.
A facile and rapid sonochemical method has been developed for the synthesis of Co2SnO4 nanostructures in presence of glucose as a green capping agent, for the first time. The effect of different parameters such as ultrasonic irradiation, time irradiation, basic agent and solvent were studied to reach optimum size and morphology conditions. The optimized Co2SnO4 nanostructures anchored onto graphene sheets and Co2SnO4/Graphene nanocomposite synthesized through pre-graphenization, successfully. In this paper, hydrogen storage capacity of optimized Co2SnO4 nanostructures and Co2SnO4/Graphene nanocomposite compared for the first time. Co2SnO4/Graphene nanocomposite show more excellent electrochemical performance than pure Co2SnO4 nanoparticles. It was found that the synergistic effect between Co2SnO4 nanoparticles and graphene sheets can improve the electrochemical performance of this hybrid composites electrode. After 25 cycles, the discharging capacities of the Co2SnO4 nanostructure and Co2SnO4/Graphene nanocomposite electrode reach 1190 and 2700 mAh/g, respectively.  相似文献   
999.
The present study evaluates adsorption of hexavalent chromium ion (Cr(VI)) from contaminated solution on nano-porous anodic aluminum oxide (AAO). The AAO sorbent was characterized by field emission scanning electron microscope (FE-SEM) and Fourier transform infrared (FTIR) spectroscope. Effects of the solution pH, contact time, and AAO quantity on Cr(VI) adsorption were investigated. It was shown that Cr(VI) adsorption on AAO was strongly pH dependent and Cr(VI) removal increased by decreasing of the pH, Cr(VI) displays anion-type sorption behavior on the AAO sorbent. Chromium ion removal of 82% was obtained at presence of 0.05 g/L AAO, pH of 1, and contact time of 40 min in the solution.  相似文献   
1000.
Limited data are available assessing the effects of vitamin D and evening primrose oil (EPO) administration on markers of insulin resistance and lipid concentrations in gestational diabetes mellitus (GDM). This study was designed to evaluate the effects of vitamin D and EPO administration on insulin resistance and lipid concentrations among women with GDM. In this prospective randomized, double‐blind, placebo‐controlled clinical trial, 60 participants with GDM were divided into 2 groups of either 1000 IU vitamin D3 and 1000 mg EPO or placebo for 6 weeks. At the beginning and end of the study, fasting blood samples were obtained from the participants to measure related variables. After 6 weeks of intervention, changes in fasting plasma glucose (?3.6 ± 7.5 vs. +1.5 ± 11.4 mg/dL, P = 0.04), serum insulin concentrations (?2.0 ± 5.3 vs. +4.6 ± 10.7 µIU/mL, P = 0.004), homeostasis model of assessment (HOMA) insulin resistance (?0.5 ± 1.1 vs. +1.1 ± 2.5, P = 0.003), HOMA‐B cell function (?7.7 ± 23.3 vs. +17.4 ± 42.9, P = 0.007) and the quantitative insulin sensitivity check index (+0.01 ± 0.02 vs. ?0.01 ± 0.02, P = 0.007) in the vitamin D plus EPO group were significantly different from the placebo group. In addition, compared with the placebo, vitamin D and EPO supplementation resulted in significant reductions in serum TAG (?20.0 ± 54.3 vs. +34.3 ± 38.2 mg/dL, P < 0.001), VLDL (?4.0 ± 10.9 vs. +6.9 ± 7.6 mg/dL, P < 0.001), TC (?22.1 ± 32.6 vs. +5.3 ± 20.1 mg/dL, P < 0.001), LDL concentrations (?18.0 ± 25.5 vs. +1.8 ± 15.7 mg/dL, P = 0.001) and TC/HDL (?0.3 ± 0.4 vs. +0.3 ± 0.5 mg/dL, P < 0.001). We did not observe any significant effect of vitamin D and EPO supplementation on serum HDL concentrations. Clinical trial registration number: http://www.irct.ir : IRCT201509115623N52.  相似文献   
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