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111.
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   
112.
Fossil fuel combustion is one of the major means to meet the mounting global energy demand. However, the increasing NOx and N2O emissions arising from fossil fuel combustion process have hazardous effects. Thus, mitigating these gases is vital to attain a sustainable environment. Interestingly, oxy-fuel combustion in fluidized bed for carbon capture and minimized NOx emissions is strongly sustainable compare to the other approaches. It was assessed that NOx formation and fuel-N conversion have significant limitation under oxy-fluidized bed compared to air mode and the mechanism of NOx formation is still deficient and requires further development. In addition, this review paper discussed the potential of primary measure as low emission process with others supplementary techniques for feasible NOx reduction. The influences of combustion mode, operating parameters, and reduction techniques such as flue gas recirculation, oxygen staging, biomass co-firing, catalyst, influence of fluidized bed design and structure, decoupling combustion and their merges are respectively evaluated. Findings show that significant minimization of NOx emission can be achieved through combination of primary and secondary reduction techniques.  相似文献   
113.
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   
114.
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   
115.
Stripping of metal ions (i.e., Cs+ and Na+) in presence of ionophore such as dibenzo-18-crown-6, (DB18C6) from the ionic liquid phase to the aqueous nitric acid phase by molecular dynamics simulation is reported. The experimentally determined stripping percentages of Na+ (i.e., 43.4, 38.5, 34.4, and 31.9%) were found to be higher than the same for Cs+ (i.e., 32.6, 32.0, 31.3, and 30.2%). The nonbonded and the hydrogen bond energies between Na+ and water (i.e., −356.41 and −363.77 kcal/mol) were higher when compared with Cs+ (i.e., −212.43 and −221.04 kcal/mol). The spatial distribution functions further confirmed that the surfaces of Na+ were very closely distributed around the active sides of water whereas for Cs+, it was distributed very far from the water molecules. In the penultimate section, the effect of methanol to the aqueous phase was studied so as to enhance the extraction efficiency of the complex.  相似文献   
116.
Protein existence in wastewater is an important issue in wastewater management because proteins are generally present as contaminants and foulants. Hence, in this study, we focused on designing a polysulfone (PSf) hollow-fiber membrane embedded with hydrophilic iron oxide nanoparticles (IONPs) for protein purification by means of ultrafiltration. Before membrane fabrication, the dispersion stability of the IONPs was enhanced by the addition of a stabilizer, namely, citric acid (CA). Next, PSf–IONP–CA nanocomposite hollow-fiber membranes were prepared via a dry–wet spinning process and then characterized in terms of their hydrophilicity and morphology. Ultrafiltration and adsorption experiments were then conducted with bovine serum albumin as a model protein. The results that an IONP/CA weight ratio of 1:20 contributed to the most stable IONP dispersion. It was also revealed that the membrane incorporated with IONP–CA at a weight ratio of 1:20 exhibited the highest pure water permeability (58.6 L m−2 h−1 bar−1) and protein rejection (98.5%) while maintaining a low protein adsorption (3.3 μg/cm2). The addition of well-dispersed IONPs enhanced the separation features of the PSf hollow-fiber membrane for protein purification. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47502.  相似文献   
117.
118.
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   
119.
120.
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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