The detailed physical processes involved in slowing glacier ablation by material cover remain poorly understood so far.In the present study,using the snow cover model SNOWPACK,the effect of geotextile cover on the ene...The detailed physical processes involved in slowing glacier ablation by material cover remain poorly understood so far.In the present study,using the snow cover model SNOWPACK,the effect of geotextile cover on the energy and mass balance at the tongue of the Urumqi Glacier No.1(Chinese Tien Shan)was simulated between July 12,2022 and August 31,2022.The mass changes and the energy fluxes with and without material cover were compared.The results indicated that the geotextile covering reduced glacier ablation by approximately 68%compared to the ablation in the uncovered regions.The high solar reflectivity of the geotextile reduced the net short-wave radiation energy available for the melt by 45%.Thermal insulation of the geotextile reduced the sensible heat flux by 15%.In addition,the wet geotextile exerted a cooling effect through long-wave radiation and negative latent heat flux.This cooling effect reduced the energy available for ablation by 20%.Consequently,only 37%of the energy was used for melting compared to that used in the uncovered regions(67%).Sensitivity experiments revealed that the geotextile cover used at a thickness range of 0.045-0.090 m reduced the ice loss by approximately 68%-72%,and a further increase in the thickness of the geotextile cover led to little improvements.A higher temperature and greater wind speed increased glacier ablation,although their effects were small.When the precipitation was set to zero,it led to a significantly increased melt.Overall,the geotextile effectively protected the glacier tongue from rapid melting,and the observed results have provided inspiration for developing an effective and sustainable approach to protect the glaciers using geotextile cover.展开更多
For describing and resolving the process of chromium ore smelting reduction in a converter preferably, the coupling dynamic model was established based on the kinetic models of chromium ore dissolution and interfacial...For describing and resolving the process of chromium ore smelting reduction in a converter preferably, the coupling dynamic model was established based on the kinetic models of chromium ore dissolution and interfacial re- ducing reaction between the slag and metal. When 150 t stainless steel crude melts with chromium of 12% are produced in a smelting reduction converter with no initial chromium in metal at 1 560℃, the results of the coupling dynamic model show that the mean reduction rate and injection rate of chromium ore are 0. 091% ·min^-1 and 467 kg · min^-1 , respectively. The foundation of the coupling dynamic model provides a reference and basis on the constitution of rational processing route for a practical stainless steelmaking.展开更多
A new method of utilizing high-silica hematite to produce low-silicon molten iron was proposed.In this method,FASTMELT,which comprised direct reduction and melt separation processes,was applied,with highly reactive bi...A new method of utilizing high-silica hematite to produce low-silicon molten iron was proposed.In this method,FASTMELT,which comprised direct reduction and melt separation processes,was applied,with highly reactive biochar as the reductant in the direct reduction stage.The proposed method was experimentally investigated and the results show that the method is feasible.In the direct reduction stage,ore-char briquette could achieve a metallization rate of 84%-88% and residual carbon of 0.27-0.89mass% at temperature of 1373 K,biochar mixing ratio of 0.8-0.9,and reduction time of 15 min.Some silica particles remained embedded in the iron phase after the reduction.In the melting separation stage,molten iron with a carbon content of 0.02-0.03mass% and silicon content of 0.02-0.18mass%could be obtained from the metallic briquettes under the above-mentioned conditions;the iron recovery rate was83%-91% and impurities in the obtained metal were negligible.展开更多
A new method （gas-based separation plus melt separation） has been proposed to remove phosphorus of the high phosphorus iron ore which was 1.25 % of phosphorus content and 50. 0% of iron content. HSC chemistry packag...A new method （gas-based separation plus melt separation） has been proposed to remove phosphorus of the high phosphorus iron ore which was 1.25 % of phosphorus content and 50. 0% of iron content. HSC chemistry package and the coexistence theory of slag structure were adopted for theoretical analysis. The gas-based reduction was carried out using a fixed bed reactor and the ore sample of 80 g with an average particle size of 2 mm were reduced using CO or H2 at temperature of 1 073 K for 5 hours. 50 g of the reduced sample with 3.0% CaO as additive was then subjected to melt separation in an electric furnace at temperature of 1 873 K under Ar atmosphere. In each run, SEM, EDS, optical microscopic examination and chemical analysis of the reduced ore sample, the metal sample and the slag sample were conducted. Results of all gas-based reduction experiments showed that iron metallization ratios were some 65% and the phosphorus compounds in the ore remained unchanged. It was agreed well with the simula- tions except for the iron metallization rate being less than predicted value; this difference was attributed to kinetics. Results of melt separation experiments showed that P content in metal samples is 0.33% （metal sample from H2 reduction product） and 0.27% （metal sample from CO reduction product）. The phosphorus partition ratios of both cases were less than predicted values. Some P in the metal samples existed as slag inclusion was considered to be the reason for this discrepancy.展开更多
采用熔体快淬法制备Fe Si Al快淬带料;利用行星式高能球磨工艺进行扁平化处理;使用真空管式炉进行氢还原退火处理;采用SEM、PPMS表征试样的形貌及室温磁滞回线;使用矢量网络分析仪测量试样在10~100 MHz频段的复磁导率;采用抗干扰性能测...采用熔体快淬法制备Fe Si Al快淬带料;利用行星式高能球磨工艺进行扁平化处理;使用真空管式炉进行氢还原退火处理;采用SEM、PPMS表征试样的形貌及室温磁滞回线;使用矢量网络分析仪测量试样在10~100 MHz频段的复磁导率;采用抗干扰性能测试系统测量表征磁片抗干扰的标签读写距离;研究影响Fe Si Al粉体材料磁性能的主要因素,并分析了其作用机理。结果表明,采用高低速两步法高能球磨处理,能有效提高薄片状Fe Si Al材料的径厚比;氢还原退火处理能有效提高饱和磁化强度和磁导率,降低矫顽力和磁损耗;制备的片状Fe Si Al材料在13.56 MHz频率附近具有优异的近场通信抗电磁干扰性能。展开更多
基金supported by the Gansu Provincial Science and Technology Program (22ZD6FA005)the State Key Laboratory of Cryospheric Science (SKLCS-ZZ-2022)+2 种基金the National Key Research and Development Program of China (2020YFF0304400)the National Natural Science Foundation of China (42001066)the National Natural Science Foundation of China (42001067).
文摘The detailed physical processes involved in slowing glacier ablation by material cover remain poorly understood so far.In the present study,using the snow cover model SNOWPACK,the effect of geotextile cover on the energy and mass balance at the tongue of the Urumqi Glacier No.1(Chinese Tien Shan)was simulated between July 12,2022 and August 31,2022.The mass changes and the energy fluxes with and without material cover were compared.The results indicated that the geotextile covering reduced glacier ablation by approximately 68%compared to the ablation in the uncovered regions.The high solar reflectivity of the geotextile reduced the net short-wave radiation energy available for the melt by 45%.Thermal insulation of the geotextile reduced the sensible heat flux by 15%.In addition,the wet geotextile exerted a cooling effect through long-wave radiation and negative latent heat flux.This cooling effect reduced the energy available for ablation by 20%.Consequently,only 37%of the energy was used for melting compared to that used in the uncovered regions(67%).Sensitivity experiments revealed that the geotextile cover used at a thickness range of 0.045-0.090 m reduced the ice loss by approximately 68%-72%,and a further increase in the thickness of the geotextile cover led to little improvements.A higher temperature and greater wind speed increased glacier ablation,although their effects were small.When the precipitation was set to zero,it led to a significantly increased melt.Overall,the geotextile effectively protected the glacier tongue from rapid melting,and the observed results have provided inspiration for developing an effective and sustainable approach to protect the glaciers using geotextile cover.
基金Sponsored by National Natural Science Foundation of China(50904017)Open Subject Fund of State Key Laboratory of Rolling and Automation of NEU of China(2009003)
文摘For describing and resolving the process of chromium ore smelting reduction in a converter preferably, the coupling dynamic model was established based on the kinetic models of chromium ore dissolution and interfacial re- ducing reaction between the slag and metal. When 150 t stainless steel crude melts with chromium of 12% are produced in a smelting reduction converter with no initial chromium in metal at 1 560℃, the results of the coupling dynamic model show that the mean reduction rate and injection rate of chromium ore are 0. 091% ·min^-1 and 467 kg · min^-1 , respectively. The foundation of the coupling dynamic model provides a reference and basis on the constitution of rational processing route for a practical stainless steelmaking.
基金the National Natural Science Foundation of China(Grant No.51144010)for the financial support
文摘A new method of utilizing high-silica hematite to produce low-silicon molten iron was proposed.In this method,FASTMELT,which comprised direct reduction and melt separation processes,was applied,with highly reactive biochar as the reductant in the direct reduction stage.The proposed method was experimentally investigated and the results show that the method is feasible.In the direct reduction stage,ore-char briquette could achieve a metallization rate of 84%-88% and residual carbon of 0.27-0.89mass% at temperature of 1373 K,biochar mixing ratio of 0.8-0.9,and reduction time of 15 min.Some silica particles remained embedded in the iron phase after the reduction.In the melting separation stage,molten iron with a carbon content of 0.02-0.03mass% and silicon content of 0.02-0.18mass%could be obtained from the metallic briquettes under the above-mentioned conditions;the iron recovery rate was83%-91% and impurities in the obtained metal were negligible.
基金Sponsored by National Natural Science Foundation of China and Baosteel(50834007)
文摘A new method （gas-based separation plus melt separation） has been proposed to remove phosphorus of the high phosphorus iron ore which was 1.25 % of phosphorus content and 50. 0% of iron content. HSC chemistry package and the coexistence theory of slag structure were adopted for theoretical analysis. The gas-based reduction was carried out using a fixed bed reactor and the ore sample of 80 g with an average particle size of 2 mm were reduced using CO or H2 at temperature of 1 073 K for 5 hours. 50 g of the reduced sample with 3.0% CaO as additive was then subjected to melt separation in an electric furnace at temperature of 1 873 K under Ar atmosphere. In each run, SEM, EDS, optical microscopic examination and chemical analysis of the reduced ore sample, the metal sample and the slag sample were conducted. Results of all gas-based reduction experiments showed that iron metallization ratios were some 65% and the phosphorus compounds in the ore remained unchanged. It was agreed well with the simula- tions except for the iron metallization rate being less than predicted value; this difference was attributed to kinetics. Results of melt separation experiments showed that P content in metal samples is 0.33% （metal sample from H2 reduction product） and 0.27% （metal sample from CO reduction product）. The phosphorus partition ratios of both cases were less than predicted values. Some P in the metal samples existed as slag inclusion was considered to be the reason for this discrepancy.
文摘采用熔体快淬法制备Fe Si Al快淬带料;利用行星式高能球磨工艺进行扁平化处理;使用真空管式炉进行氢还原退火处理;采用SEM、PPMS表征试样的形貌及室温磁滞回线;使用矢量网络分析仪测量试样在10~100 MHz频段的复磁导率;采用抗干扰性能测试系统测量表征磁片抗干扰的标签读写距离;研究影响Fe Si Al粉体材料磁性能的主要因素,并分析了其作用机理。结果表明,采用高低速两步法高能球磨处理,能有效提高薄片状Fe Si Al材料的径厚比;氢还原退火处理能有效提高饱和磁化强度和磁导率,降低矫顽力和磁损耗;制备的片状Fe Si Al材料在13.56 MHz频率附近具有优异的近场通信抗电磁干扰性能。
