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131.
This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control and lipid profiles among overweight and obese subjects. We searched the following databases through November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. Data were pooled using the inverse variance method and expressed as Standardized Mean Difference (SMD) with 95% Confidence Intervals (95% CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Overall, 14 studies were included in the meta-analyses. Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD ?0.66; 95% CI, ?1.31, ?0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD ?0.49; 95% CI, ?0.82, ?0.17; P = 0.003), hip ratio (HR) (SMD ?0.42; 95% CI, ?0.77, ?0.08; P = 0.01), fasting glucose (SMD ?0.68; 95% CI, ?1.23, ?0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD ?1.67; 95% CI, ?2.86, ?0.48; P = 0.006), and significantly increased HDL-cholesterol levels (SMD 0.40; 95% CI, 0.10, 0.70; P = 0.009). We found no detrimental effect of ginger on body mass index (BMI) (SMD ?0.65; 95% CI, ?1.36, 0.06; P = 0.074), insulin (SMD ?0.54; 95% CI, ?1.43, 0.35; P = 0.23), triglycerides (SMD ?0.27; 95% CI, ?0.71, 0.18; P = 0.24), total- (SMD ?0.20; 95% CI, ?0.58, 0.18; P = 0.30) and LDL-cholesterol (SMD ?0.13; 95% CI, ?0.51, 0.24; P = 0.48). Overall, the current meta-analysis demonstrated that ginger intake reduced BW, WHR, HR, fasting glucose and HOMA-IR, and increased HDL-cholesterol, but did not affect insulin, BMI, triglycerides, total- and LDL-cholesterol levels.  相似文献   
132.
Fibrous monoliths (FMs) exhibit graceful failure in flexure and have higher toughness values. In this research, a mixture of Al2O3 and SiC as the core and graphite as the shell material of fibers were produced by extrusion-molding technique and after aligning along intended directions (0°, 90°, and 0°/90°) were sintered using the hot-pressing method at the temperature of 1500°C under pressure of 35 MPa for 1 hour. The significance of fibers orientation angle and the cell to cell boundary volume ratio in defining the fracture behavior of the FMs was detected. Because of the extensive crack interactions with graphite cell boundary such as crack deflection and delamination, with increasing cell boundary content from 25 to 30 vol%, the fracture toughness was enhanced. The highest flexural strength (184.8 ± 0.61 MPa) obtained from samples with 0° fibers orientation compared to 0°/90°. Since in the transverse plies (layers with 90° aligning), the properties of matrix phase are dominant, hence the strength in specimens with 0°/90° fibers orientation decreased considerably due to weak graphite matrix phase. In addition, the fracture toughness value increased up to 8.35 ± 0.74 MPa·m1/2 for the unidirectional architecture of (0°) in comparison with cross-ply (0°/90°) architecture.  相似文献   
133.
Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic acid.The as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m^2· g^-1.Experimental results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 min.This is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH NPs.These NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.  相似文献   
134.
Compression garments mainly produced from elastic knitted fabrics have attracted many attentions due to their medical care performances. Components’ characteristics of the pressure garments such as yarn and fabric structure affect significantly the pressure applied on the human body. In this paper, it is aimed to simulate the effect of yarn’s mechanical properties as well as fabric structure on mechanical performance of the compression garment. For this purpose, a precise geometrical model for fabric structure is needed by which the pressure applied to the body could be predicted. Accordingly, double jersey knitted fabrics containing elastane weft yarns were produced on an electronic flat knitting machine and the fabric tensile properties were measured in course direction. Using equations governing the fabric structural unit-cell, a real geometric model was created in a finite element software environment. Considering the linear visco-elastic properties for elastane weft yarn, stress-strain curve was extracted. The results obtained from numerical simulation were compared with the experimental data in order to validate the proposed geometrical model. The findings demonstrate a good agreement between experimental and simulation results.  相似文献   
135.
Silicon - Thermodynamic stability, electronic and optical properties of the Zr2TiSi compound in the bulk and its [111] films have been investigated, based on the density functional theory (DFT)...  相似文献   
136.
Protection of Metals and Physical Chemistry of Surfaces - The effect of annealing temperature on the properties of silver thin films has been investigated. Ag thin films have been deposited on...  相似文献   
137.
Phytic acid–modified layered double hydroxide (Ph‐LDH) was synthesized via coprecipitation method and subsequently was used in polypropylene (PP) by combining with an ammonium polyphosphate (APP) via melt compounding method. The synergistic effect between APP and Ph‐LDH on the thermal stability, flammability, and mechanical properties of the resultant PP composites was investigated by thermogravimetric analysis, limiting oxygen index, vertical burning test (UL‐94), cone calorimeter tests, tensile test, and impact test. Morphologies of the chars obtained from the samples after the cone calorimeter tests were studied by scanning electron microscopy. The combination of APP and Ph‐LDH slightly influenced the impact and tensile properties of PP. Also, the synergistic effect between APP and Ph‐LDH occurred in the cone calorimeter test. Moreover, the combination of APP and Ph‐LDH produced better quality char that effectively suppressed the spread of the flame and volatile and finally extinguished the fire.  相似文献   
138.
This work aims to improve the rheological properties and stability of multiwalled carbon nanotubes (MWCNTs)/acrylamide (AA) base skeleton polymer blends at harsh environment of high salinity-high temperature (HS-HT) or various pH. Different co/terpolymers have been accomplished to modify the structure of AA polymer by free-radical copolymerization of AA-based monomers. Anionic, cationic, and hydrophobic functional groups were used for the synthesis of polyelectrolyte, polyampholytic, and partially hydrophobic AA polymer types. The conversion, molecular weight, and poly dispersity of co/terpolymers have been evaluated by nuclear magnetic resonance (1H-NMR), gel permeation chromatography, and differential scanning calorimetry analysis. The effects of sonication power, concentration of polymer, and concentration of MWCNTs were also investigated on rheological behavior of co/terpolymers. The results show that negative polyelectrolyte and polyampholytic polymers are the best candidates for the improvement of MWCNTs/polymer stability and viscosity at HS-HT and alkali environment, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47205.  相似文献   
139.
A combination of reduced graphene oxide (rGO) nanosheets grafted with regioregular poly(3‐hexylthiophene) (P3HT) (rGO‐g‐P3HT) and P3HT‐b‐polystyrene (PS) block copolymers was utilized to modify the morphology of P3HT:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) active layers in photovoltaic devices. Efficiencies greater than 6% were acquired after a mild thermal annealing. To this end, the assembling of P3HT homopolymers and P3HT‐b‐PS block copolymers onto rGO‐g‐P3HT nanosheets was investigated, showing that the copolymers were assembled from the P3HT side onto the rGO‐g‐P3HT nanosheets. Assembling of P3HT‐b‐PS block copolymers onto the rGO‐g‐P3HT nanosheets developed the net hole and electron highways for charge transport, thereby in addition to photoluminescence quenching the charge mobility (μh and μe) values increased considerably. The best charge mobilities were acquired for the P3HT50000:PC71BM:rGO‐g‐P3HT50000:P3HT7000b‐PS1000 system (μh = 1.9 × 10?5 cm2 V–1 s–1 and μe = 0.8 × 10?4 cm2 V–1 s–1). Thermal annealing conducted at 120 °C also further increased the hole and electron mobilities to 9.8 × 10?4 and 2.7 × 10?3 cm2 V–1 s–1, respectively. The thermal annealing acted as a driving force for better assembly of the P3HT‐b‐PS copolymers onto the rGO‐g‐P3HT nanosheets. This phenomenon improved the short circuit current density, fill factor, open circuit voltage and power conversion efficiency parameters from 11.13 mA cm?2, 0.63 V, 62% and 4.35% to 12.98 mA cm?2, 0.69 V, 68% and 6.09%, respectively. © 2019 Society of Chemical Industry  相似文献   
140.
Water splitting toward hydrogen production is a promising method to store energy, but water oxidation is a bottleneck for water splitting. First-row transition metal complexes have been extensively used for water-oxidation reaction. However, only one chromium complex has been applied for water-oxidation reaction until now. Thus, the reinvestigation of water-oxidation reaction by this chromium complex in detail is interesting. Herein, water-oxidation reaction by the chromium complex with diphenoxy N,N′-ethylenebis(salicylimine) (SALEN) ligand is reinvestigated using scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction studies, X-ray photoelectron spectroscopy, thermal gravimetric analysis, elemental analysis, Fourier-transform infrared spectroscopy, and electrochemical methods. All the experiments showed that the chromium complex is neither a catalyst nor a precatalyst for water-oxidation reaction. During OER, a relationship between first-row transition metal complexes and the related metal oxides has been proposed.  相似文献   
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