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Nonlinear Reduction in Risk for Type 2 Diabetes by Magnesium Intake:An Updated Meta-Analysis of Prospective Cohort Studies 被引量:5
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作者 XU Tian CHEN Guo Chong +1 位作者 ZHAI Lin KE Kai Fu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第7期527-534,共8页
Observational studies between magnesium int- ake and risk of type 2 diabetes yielded inconsistent results. We conducted a system literature search of PubMed database through March 2015 for prospective cohort studies o... Observational studies between magnesium int- ake and risk of type 2 diabetes yielded inconsistent results. We conducted a system literature search of PubMed database through March 2015 for prospective cohort studies of magnesium intake and type 2 diabetes risk. Study-specific results were pooled in a random-effects model. Subgroup and sensitivity analysis were performed to assess the potential sources of heterogeneity and the robustness of the pooled estimation. Generalized least squares trend estimation was used to investigate the dose-response relationship. A total of 15 papers with 19 analyses were identified with 539,735 participants and 25,252 incident diabetes cases. Magnesium intake was associated with a significant lower risk of type 2 diabetes (RR: 0.77; 95% Ch 0.71-0.82) for the highest compared with lowest category. This association was not significantly modified by the pre-specified study characteristics. In the dose-response analysis, a magnesium intake increment of 100 mg/day was associated with a 16% reduction in type 2 diabetes risk (RR: 0.84; 95% Ch 0.80-0.88). A nonlinear relationship existed between magnesium intake and type 2 diabetes (P-nonlinearity=0.003). This meta-analysis further verified a protective effect of magnesium intake on type 2 diabetes in a nonlinear dose-response manner. 展开更多
关键词 Nonlinear reduction in Risk for Type 2 Diabetes by magnesium Intake meta
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Reaction characteristics of magnesium production under argon flow by silicothermic reduction and numerical simulation of argon entrainment process
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作者 Shiming Zhang Chao Zhang +3 位作者 Gengpeng Mai Jianxun Song Yusi Che Jilin He 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第10期3710-3723,共14页
In this study, the reaction characteristics of reduction of calcined dolomite with ferrosilicon under argon flow to produce magnesium were studied by conducting experiments Pidgeon pellets were used to study the effec... In this study, the reaction characteristics of reduction of calcined dolomite with ferrosilicon under argon flow to produce magnesium were studied by conducting experiments Pidgeon pellets were used to study the effect of reduced temperature, argon flow, and reduced time on the conversion of calcined dolomite reduction by ferrosilicon. The results show that the conversion significantly increases with the increase in the reduction temperature and reduction time. The conversion first increases and then decreases with the increase in argon flow. The highest conversion was obtained when the argon flow rate was 3 L·min^(-1), and a nearly spherical shape, nanoscale magnesium powder was obtained. Then the characters of the circulating argon entrainment process were numerically studied by ANSYS Fluent 17. A physical model of multilayer pellet arrangement was established, and a numerical calculation model of chemical reaction, radiation, heat conduction, and convection heat transfer was constructed. This confirms that high-temperature argon can effectively strengthen the heat exchange between pellets, improve the heat transfer efficiency, and facilitate the pellets to react quickly. When the conversion is 80%, the production efficiency increased by about 28.6%. In addition, the magnesium production efficiency showed an increase tendency with the increase of the argon inlet flow rate. 展开更多
关键词 Silicothermic reduction of magnesium Enhanced heat transfer Convection heat transfer Numerical simulation Argon flow
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Kinetics of magnesium preparation by vacuum-assisted carbothermic reduction method
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作者 Wei-dong Xie Jie Chen +3 位作者 Hao Wang Xi Zhang Xiao-dong Peng Yan Yang 《Rare Metals》 SCIE EI CAS CSCD 2016年第2期192-197,共6页
Metallic magnesium was prepared by vacuumassisted carbothermic reduction method, and its morphologies were observed and analyzed. The reduction ratios of reactions were carried out under various vacuums, reaction temp... Metallic magnesium was prepared by vacuumassisted carbothermic reduction method, and its morphologies were observed and analyzed. The reduction ratios of reactions were carried out under various vacuums, reaction temperatures, and time. Reaction kinetics of carbothermic reduction process was investigated. The results reveal that the morphologies of metallic magnesium sample that crystallized in the bottom and top sections of the condensation cap appear as the shape of feather with close-packing needle structure and the shape of schistose with metal luster,compactly clumpy structure, respectively. The reduction ratio of reaction process can be facilitated through reducing vacuum, increasing temperature, lengthening time, or their combinations and can reach up to 83.7 % under the condition of 10 Pa and 1573 K with 60 min reaction time. At1423-1573 K, the reaction rate constant k of carbothermic reduction of magnesia in vacuum gets greater with the increase of temperature. The reaction activity energy is190.28, 219.71 and 451.12-528.54 k J mol-1when the procedure of carbon gasification reaction, interfacial reaction, or gaseous diffusion is the reaction rate-determining step at 1423-1573 K, respectively. The gaseous diffusion procedure has the largest activity energy value and is,therefore, the main reaction rate-determining step. 展开更多
关键词 magnesium Carbothermic reduction Magnesia Vacuum Kinetics
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Preparation and lithium storage performances of g-C_(3)N_(4)/Si nanocomposites as anode materials for lithium-ion battery 被引量:3
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作者 Zhengxu BIAN Zehua TANG +6 位作者 Jinfeng XIE Junhao ZHANG Xingmei GUO Yuanjun LIU Aihua YUAN Feng ZHANG Qinghong KONG 《Frontiers in Energy》 SCIE CSCD 2020年第4期759-766,共8页
As the anode material of lithium-ion battery,silicon-based materials have a high theoretical capacity,but their volume changes greatly in the charging and discharging process.To ameliorate the volume expansion issue o... As the anode material of lithium-ion battery,silicon-based materials have a high theoretical capacity,but their volume changes greatly in the charging and discharging process.To ameliorate the volume expansion issue of silicobased anode materials,g-C_(3)N_(4)/Si nanocomposites are prepared by using the magnesium thermal reduction technique.It is well known that g-C_(3)N_(4)/Si nanocomposites can not only improve the electronic transmission ability,but also ameliorate the physical properties of the material for adapting the stress and strain caused by the volume expansion of silicon in the lithiation and delithiation process.When g-C_(3)N_(4)/Si electrode is evaluated,the initial discharge capacity of g-C_(3)N_(4)/Si nanocomposites is as high as 1033.3 mAh/g at 0.1 A/g,and its reversible capacity is maintained at 548 mAh/g after 400 cycles.Meanwhile,the improved rate capability is achieved with a relatively high reversible specific capacity of 218 mAh/g at 2.0 A/g.The superior lithium storage performances benefit from the unique g-C_(3)N_(4)/Si nanostructure,which improves electroconductivity,reduces volume expansion,and accelerates lithiumion transmission compared to pure silicon. 展开更多
关键词 magnesium thermal reduction g-C_(3)N_(4)/Si nanocomposites volume expansion ELECTROCONDUCTIVITY lithium-ion battery
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