A systematic investigation on the effect of milling time on carbothermic reduction of ilmenite was carried out by a combination of thermal analysis, X-ray diffraction（XRD）, scanning electron microscopy（SEM） and pa...A systematic investigation on the effect of milling time on carbothermic reduction of ilmenite was carried out by a combination of thermal analysis, X-ray diffraction（XRD）, scanning electron microscopy（SEM） and particle size analysis. It was shown that the graphite crystalline structure was easily destroyed along the（002） crystal plane during milling process. The particle size of ilmenite/graphite mixture was largely decreased and a fully mixed composite structure was obtained after milling for 4 h at high milling intensity. Milling exerts positive effect on the decreasing temperatures of ilmenite reduction and gradual deoxidizing of titanium oxides was completed.展开更多
With LiAc-2H2O as Li precursor,pure olivine phase LiFePO4/C was synthesized at a relatively low temperature（650 ℃） and short sintering period（4 h） by molten salt carbothermal reduction method.Scanning electron mi...With LiAc-2H2O as Li precursor,pure olivine phase LiFePO4/C was synthesized at a relatively low temperature（650 ℃） and short sintering period（4 h） by molten salt carbothermal reduction method.Scanning electron micrograph shows that particle size of the product is about 1μm,smaller than that of the sample synthesized with Li2CO3 as Li precursor.Electrochemical measurements prove that LiFePO4/C obtained from LiAc-2H2O shows high capacity.The initial discharge capacities are 148 mA-h/g at 0.5C rate and 115 mA-h/g at 5C rate,respectively.After 50 cycles,the capacity retention ratios are 93% and 89% at 0.5C rate and 5C rate,respectively.展开更多
GasTurbnLab: a multidisciplinary problem solving environment for gas turbine engine design on a network of nonhomogeneous machines； Heat transfer coefficient on the squealer tip and near squealer tip regions of a gas...GasTurbnLab: a multidisciplinary problem solving environment for gas turbine engine design on a network of nonhomogeneous machines； Heat transfer coefficient on the squealer tip and near squealer tip regions of a gas turbine blade；Hybrid-ceramic circumferential carbon ring seal； Impact Resistance of Lightweight Hybrid Structures for Gas Turbine Engine Fan Containment Applications；展开更多
[Objective] Ginger essential oil （GEO） is widely used in food production and medical field in recent years due to its prominent biological functions, and this study was conducted to obtain high-quality and high-puri...[Objective] Ginger essential oil （GEO） is widely used in food production and medical field in recent years due to its prominent biological functions, and this study was conducted to obtain high-quality and high-purity ginger essential oil from the fresh ginger. [Method] GEO was extracted from ginger roots by supercritical fluid extraction （SFE） method. The effects of flow rate of CO2, mesh size of ginger powder and volume of entrainer were investigated by single-factor experiments and response surface method. The content and extraction rate of 6-gingerol represented the extraction index of GEO. [Result] The conditions were optimized as follows： flow rate of CO2 at 25 L/h, mesh size of ginger power of 80 mesh, and volume of anhydrous ethanol as entrainer of 92.46 ml. The optimal extraction rate of 6-gingerol was 3.21%, which was predicted by RSM. [Conclusion] The optimal process of supercritical carbon dioxide extraction of ginger essential oil was identified by singlefactor experiments and response surface method. The present study provides a satisfactory method for purifying GEO from ginger for industrial purpose.展开更多
In global change research, changes of soil organic carbon (SOC) reservoirs intropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stockswas determined in a basin of over 579 km^2...In global change research, changes of soil organic carbon (SOC) reservoirs intropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stockswas determined in a basin of over 579 km^2 in subtropical China from 1981to 2002. ArcGIS8.l softwarewas utilized for spatial analysis of semivariance, ordinary kriging (OK), and probability kriging(PK). Grid and hierarchical approaches were employed for the sampling scenario in 2002 with 106Global Position System (GPS) established spots sampled. Bulk topsoil samples (0—30 cm) werecollected at three random sites on each spot. The SOC content for 1981 came from the SOC map of theSecond National Soil Survey. Geostatistical results of the nugget to sill ratio (0.215-0.640)in therehabilitating ecosystem indicated a moderate spatial dependence for SOC on this large scale. Therange of SOC changed from 2.04 km in 1981 to 7.15 km in 2002. The mean topsoil SOC increased by 4.6%from 10.63 g kg^(-1) (1981) to 11.12 g kg^(-1)(2002). However, during this 21-year period 25.2% ofthe total basin area experienced a decrease in SOC. Also, the probability kriging results showedthat the geometric mean probabilities of SOC <= 6.0 g kg^(-1), <= 11.0 g kg^(-1) and > 15.0 gkg^(-1) were 0.188, 0.534 and 0.378, respectively in 2002, comparing to 0.234, 0.416 and 0.234 inthat order in 1981, respectively. The SOC storage in the topsoil increased by 17.0% during this timewith the main increase occurring in forests and cultivated land,which amounted to 82.5% and 17.0%of the total increase, respectively.展开更多
A clean and efficient route for the utilization of ilmenite concentrates was proposed by direct carbothermic reduction in microwave field.High dosage of Na_(2)CO_(3),which can be recycled,was added to accelerate the r...A clean and efficient route for the utilization of ilmenite concentrates was proposed by direct carbothermic reduction in microwave field.High dosage of Na_(2)CO_(3),which can be recycled,was added to accelerate the reduction reaction of ilmenite concentrates.After microwave heating in the temperature range of 1073−1123 K for 20 min,the main products were Na_(2)TiO_(3) and metallic Fe with the metallization ratios being as high as 92.67%−93.21%.The reduction products were processed by water leaching,ball-milling in CO2 atmosphere and magnetic separation in turn.The final products after magnetic separation were Fe-rich materials and Ti-rich materials(90.04 wt.%TiO2),which can be used to produce iron and TiCl4 or TiO2.The optimized heating temperature was 1123 K in terms of metallization ratios,magnetic separation and caking property of the reduction products.Besides,the reduction mechanism of ilmenite concentrates with the addition of Na_(2)CO_(3) in microwave field was also proposed.展开更多
基金Project(2014JY0132)supported by the Program for Application Basic Research of Sichuan ProvinceChina+5 种基金Projects(2013CY-G-72014CY-G-26-12015CY-G-18)supported by the Technology Research Program of Panzhihua CityChinaProject(2015TX-11)supported by the Innovative Project of Panzhihua CityChina
文摘A systematic investigation on the effect of milling time on carbothermic reduction of ilmenite was carried out by a combination of thermal analysis, X-ray diffraction（XRD）, scanning electron microscopy（SEM） and particle size analysis. It was shown that the graphite crystalline structure was easily destroyed along the（002） crystal plane during milling process. The particle size of ilmenite/graphite mixture was largely decreased and a fully mixed composite structure was obtained after milling for 4 h at high milling intensity. Milling exerts positive effect on the decreasing temperatures of ilmenite reduction and gradual deoxidizing of titanium oxides was completed.
基金Project(21001041) supported by the National Natural Science Foundation of ChinaProject(102300410256) supported by Henan Province Foundation and Advanced Technology Research Program,China+1 种基金Project(102102210183) supported by the Key Scientific and Technological Research Project of Henan Province,ChinaProject(2011B480005) supported by the Natural Science Research Project of Henan Province,China
文摘With LiAc-2H2O as Li precursor,pure olivine phase LiFePO4/C was synthesized at a relatively low temperature（650 ℃） and short sintering period（4 h） by molten salt carbothermal reduction method.Scanning electron micrograph shows that particle size of the product is about 1μm,smaller than that of the sample synthesized with Li2CO3 as Li precursor.Electrochemical measurements prove that LiFePO4/C obtained from LiAc-2H2O shows high capacity.The initial discharge capacities are 148 mA-h/g at 0.5C rate and 115 mA-h/g at 5C rate,respectively.After 50 cycles,the capacity retention ratios are 93% and 89% at 0.5C rate and 5C rate,respectively.
文摘GasTurbnLab: a multidisciplinary problem solving environment for gas turbine engine design on a network of nonhomogeneous machines； Heat transfer coefficient on the squealer tip and near squealer tip regions of a gas turbine blade；Hybrid-ceramic circumferential carbon ring seal； Impact Resistance of Lightweight Hybrid Structures for Gas Turbine Engine Fan Containment Applications；
基金Supported by the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(16KJA550001)~~
文摘[Objective] Ginger essential oil （GEO） is widely used in food production and medical field in recent years due to its prominent biological functions, and this study was conducted to obtain high-quality and high-purity ginger essential oil from the fresh ginger. [Method] GEO was extracted from ginger roots by supercritical fluid extraction （SFE） method. The effects of flow rate of CO2, mesh size of ginger powder and volume of entrainer were investigated by single-factor experiments and response surface method. The content and extraction rate of 6-gingerol represented the extraction index of GEO. [Result] The conditions were optimized as follows： flow rate of CO2 at 25 L/h, mesh size of ginger power of 80 mesh, and volume of anhydrous ethanol as entrainer of 92.46 ml. The optimal extraction rate of 6-gingerol was 3.21%, which was predicted by RSM. [Conclusion] The optimal process of supercritical carbon dioxide extraction of ginger essential oil was identified by singlefactor experiments and response surface method. The present study provides a satisfactory method for purifying GEO from ginger for industrial purpose.
基金Project supported by the National Key Basic Research Support Foundation of China (No. G1999011801) the Knowledge Innovation Program of Chinese Acacemy of Sciences (Nos. KZCX2-413 and ISSASIP0110).
文摘In global change research, changes of soil organic carbon (SOC) reservoirs intropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stockswas determined in a basin of over 579 km^2 in subtropical China from 1981to 2002. ArcGIS8.l softwarewas utilized for spatial analysis of semivariance, ordinary kriging (OK), and probability kriging(PK). Grid and hierarchical approaches were employed for the sampling scenario in 2002 with 106Global Position System (GPS) established spots sampled. Bulk topsoil samples (0—30 cm) werecollected at three random sites on each spot. The SOC content for 1981 came from the SOC map of theSecond National Soil Survey. Geostatistical results of the nugget to sill ratio (0.215-0.640)in therehabilitating ecosystem indicated a moderate spatial dependence for SOC on this large scale. Therange of SOC changed from 2.04 km in 1981 to 7.15 km in 2002. The mean topsoil SOC increased by 4.6%from 10.63 g kg^(-1) (1981) to 11.12 g kg^(-1)(2002). However, during this 21-year period 25.2% ofthe total basin area experienced a decrease in SOC. Also, the probability kriging results showedthat the geometric mean probabilities of SOC <= 6.0 g kg^(-1), <= 11.0 g kg^(-1) and > 15.0 gkg^(-1) were 0.188, 0.534 and 0.378, respectively in 2002, comparing to 0.234, 0.416 and 0.234 inthat order in 1981, respectively. The SOC storage in the topsoil increased by 17.0% during this timewith the main increase occurring in forests and cultivated land,which amounted to 82.5% and 17.0%of the total increase, respectively.
基金financially supported by the National Natural Science Foundation of China(Nos.51734002,51474141)China Postdoctoral Science Foundation(No.2020M671071)Independent Research and Development Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University,China(No.SKLASS 2019-Z014)。
文摘A clean and efficient route for the utilization of ilmenite concentrates was proposed by direct carbothermic reduction in microwave field.High dosage of Na_(2)CO_(3),which can be recycled,was added to accelerate the reduction reaction of ilmenite concentrates.After microwave heating in the temperature range of 1073−1123 K for 20 min,the main products were Na_(2)TiO_(3) and metallic Fe with the metallization ratios being as high as 92.67%−93.21%.The reduction products were processed by water leaching,ball-milling in CO2 atmosphere and magnetic separation in turn.The final products after magnetic separation were Fe-rich materials and Ti-rich materials(90.04 wt.%TiO2),which can be used to produce iron and TiCl4 or TiO2.The optimized heating temperature was 1123 K in terms of metallization ratios,magnetic separation and caking property of the reduction products.Besides,the reduction mechanism of ilmenite concentrates with the addition of Na_(2)CO_(3) in microwave field was also proposed.
