In Liaoning, Hunan, Guangxi, Guizhou, Gansu, Sichuan, Anhui, Jilin and other provinces in China, there is a wide occurrence of metal quantity over 1000 tons of refractory gold ores, principally because of low gold rec...In Liaoning, Hunan, Guangxi, Guizhou, Gansu, Sichuan, Anhui, Jilin and other provinces in China, there is a wide occurrence of metal quantity over 1000 tons of refractory gold ores, principally because of low gold recoveries and become ＂stay mine＂. Features of refi＇actory gold ores are： gold in micro-particles or a microscopic state that is wrapped in pyrite, presence of arsenopyrite and other sulfide minerals or disseminated in the crystal lattice of sulfide minerals; harmful impurity elements such as arsenic, carbon, mercury, antimony, copper with high content are closely related with the gold, and these elements affect the contact reaction between the gold and solvent extraction, making the recovery of the gold extraction process low. In the past 20 years, overseas countries have developed the application of the roasting oxidation method, hot acid （alkali） oxidation, bacterial oxidation and flash chlorination oxidation technology to solve this problem.Among these, biological oxidation has developed rapidly in the domestic market and gold enterprises abroad because of its low investment in infrastructure, low production costs, less environmental pollution, simple process and easy control, etc.展开更多
This paper presents a comparative analysis of the International Baccalaureate(IB)and the General Certificate of Education Advanced Level(A-Level),two international educational assessment systems.The study explores the...This paper presents a comparative analysis of the International Baccalaureate(IB)and the General Certificate of Education Advanced Level(A-Level),two international educational assessment systems.The study explores their similarities and differences in educational philosophy,curriculum design,assessment methods,and student experience.Findings indicate that the IB curriculum emphasizes holistic education and interdisciplinary learning,while the A-Level curriculum focuses more on subject depth and specialization.In terms of assessment methods,the IB combines internal and external evaluations,whereas the A-Level primarily relies on final examinations.Regarding student experience,IB students typically perceive a broader range of learning opportunities,while A-Level students gain in-depth knowledge in specific subject areas.The study offers valuable insights for educators and policymakers to improve educational practices and support the personalized development of students.展开更多
文摘In Liaoning, Hunan, Guangxi, Guizhou, Gansu, Sichuan, Anhui, Jilin and other provinces in China, there is a wide occurrence of metal quantity over 1000 tons of refractory gold ores, principally because of low gold recoveries and become ＂stay mine＂. Features of refi＇actory gold ores are： gold in micro-particles or a microscopic state that is wrapped in pyrite, presence of arsenopyrite and other sulfide minerals or disseminated in the crystal lattice of sulfide minerals; harmful impurity elements such as arsenic, carbon, mercury, antimony, copper with high content are closely related with the gold, and these elements affect the contact reaction between the gold and solvent extraction, making the recovery of the gold extraction process low. In the past 20 years, overseas countries have developed the application of the roasting oxidation method, hot acid （alkali） oxidation, bacterial oxidation and flash chlorination oxidation technology to solve this problem.Among these, biological oxidation has developed rapidly in the domestic market and gold enterprises abroad because of its low investment in infrastructure, low production costs, less environmental pollution, simple process and easy control, etc.
文摘This paper presents a comparative analysis of the International Baccalaureate(IB)and the General Certificate of Education Advanced Level(A-Level),two international educational assessment systems.The study explores their similarities and differences in educational philosophy,curriculum design,assessment methods,and student experience.Findings indicate that the IB curriculum emphasizes holistic education and interdisciplinary learning,while the A-Level curriculum focuses more on subject depth and specialization.In terms of assessment methods,the IB combines internal and external evaluations,whereas the A-Level primarily relies on final examinations.Regarding student experience,IB students typically perceive a broader range of learning opportunities,while A-Level students gain in-depth knowledge in specific subject areas.The study offers valuable insights for educators and policymakers to improve educational practices and support the personalized development of students.
