To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere fo...To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere followed by grind-leaching,magnetic separation,and CO_(2) carbonation.The effects of roasting temperature,roasting time,CO/(CO+CO_(2))composition,and Na_(2)CO_(3) dosage on the boron and iron separation indices were primarily investigated.Under the optimized conditions of the roasting temperature of 850℃,roasting time of 60 min,soda ash dosage of 20 wt%,and CO/(CO+CO_(2)) of 10 vol%,92%of boron was leached during wet grinding,and 88.6%of iron was recovered during the magnetic separation and magnetic concentrate with a total iron content of 61.51 wt%.Raman spectra and^(11)B NMR results indicated that boron exists asB(OH)_(4)^(-) in the leachate,from which high-purity borax pentahydrate could be prepared by CO_(2) carbonation.展开更多
The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and ...The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Nirich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi-MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages： deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu-Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies.展开更多
Long-term field monitoring finds that serious surface subsidence can still occur even if the high strength cemented fill method is adopted.Combining the results of numerical simulations with global position system(GPS...Long-term field monitoring finds that serious surface subsidence can still occur even if the high strength cemented fill method is adopted.Combining the results of numerical simulations with global position system(GPS)monitoring,we took a typical filling mining mine with a steeply inclined ore body as an example,and explored its ground subsidence mechanism.The results show that the ground subsidence caused by the mining of steep ore body is characterized by two settlement centers and a significantly uneven spatial distribution,which is visibly different from ground subsidence characteristic of the coal mine.The subsidence on the hanging wall is much larger than that on the footwall,and the settlement center tends to move to the hanging wall with the increase of mining depth.The backfill improves the strength and surrounding rock bearing capacity,which leads to a lag of about 3 years of the subsidence.However,under the actions of continuous and repeated mining disturbances,the supporting effect of the backfill can only reduce the amplitude of the deformation,but it cannot prevent the occurrence of settlement.展开更多
AIM:To explore whether cyclooxygenase 2(COX-2) -765G>C polymorphism is associated with susceptibility of colorectal cancer(CRC)and to evaluate the risk of colorectal cancer in relation to environmental exposures an...AIM:To explore whether cyclooxygenase 2(COX-2) -765G>C polymorphism is associated with susceptibility of colorectal cancer(CRC)and to evaluate the risk of colorectal cancer in relation to environmental exposures and polymorphism. METHODS:We conducted a case-control study of 137 patients with colorectal cancer and 199 cancer- free controls in northeast China.Multivariate logistic regression analysis was performed to calculate the adjusted odds ratio(OR)and 95% confidence interval (95%CI). RESULTS:The-765G>C polymorphism was not independently associated with CRC risk.However,risk associated with the polymorphism differed by smoking and body mass index(BMI).Smoking and BMI associated risks were stronger among those with-765GG genotype, showing that smokers had a 2.682-fold greater risk of CRC than nonsmokers(51/43 vs 68/126,P=0.006). Compared to those with a normal body mass index(BMI 18.5-22.9),those with overweight(BMI 23-24.9)had a 3.909-fold higher risk of CRC(OR=3.909,95% CI= 2.081-7.344;P<0.001),while those with obesity(BMI >25)had a 2.031-fold higher risk of CRC(OR=1.107, 95% CI=1.107-3.726;P=0.022). CONCLUSION:Although COX-2-765G>C polymorphismis not associated with an increased risk of CRC,-765GG genotype appears to be related to an increased risk in the presence of smoking and higher BMI.展开更多
1 Geological Background of Minerlization or Geologic Setting The northeast of Yunnan1 Pb-Zn-Ag-Ge polymetallic ore district is an important part of the southwestern margin of the Yangtze block Sichuan-Yunnan-Guizhou
目的 在高体重指数(body mass index, BMI)率快速增长的情况下,分析1990-2019年中国归因于高BMI的2型糖尿病疾病负担。方法 基于2019年全球疾病负担研究数据,分性别、年龄组分析1990-2019年中国因高BMI造成的2型糖尿病疾病负担,并利用Jo...目的 在高体重指数(body mass index, BMI)率快速增长的情况下,分析1990-2019年中国归因于高BMI的2型糖尿病疾病负担。方法 基于2019年全球疾病负担研究数据,分性别、年龄组分析1990-2019年中国因高BMI造成的2型糖尿病疾病负担,并利用Joinpoint回归模型分析标化后的归因死亡率和归因伤残调整寿命年(disability-adjusted life year, DALY)率的变化趋势。结果 1990-2019年间,我国2型糖尿病患病率从2928.78/10万增至6328.79/10万,归因高BMI的2型糖尿病死亡人数从1.05万增至4.75万,标化死亡率从1.25/10万增至2.39/10万;归因DALY从77.18万人年增至373.76万人年,标化后的归因DALY率从80.21/10万增至181.54/10万,早死损失寿命年(years of life lost, YLL)和伤残损失寿命年(year lived with disability, YLD)及其标化率也呈大幅增长。1990-2019年间,我国归因于高BMI的2型糖尿病标化死亡率和标化DALY率的年平均变化百分比分别为2.28%和2.81%,均有统计学意义(P<0.05),且男性均高于女性。男性标化后的归因DALY率和归因死亡率分别在2010年和2014年超过女性。年龄分层结果显示,50岁以上人群高BMI导致的2型糖尿病疾病负担更加严重,15~49岁人群归因于高BMI的YLD率增幅最大,达到323.99%。结论 1990-2019年间,中国归因于高BMI的2型糖尿病疾病负担显著增加。需加大防控力度,有效管理人群体重指数,并对高危人群采取重点干预,以减轻2型糖尿病疾病负担。展开更多
基金financially supported by the National Key Research and Development Program of China(No.2020YFC1909803)the Basic Science Center Project for the National Natural Science Foundation of China(No.72088101)the Graduate Research and Innovative Project of Central South University(No.506021739)。
文摘To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere followed by grind-leaching,magnetic separation,and CO_(2) carbonation.The effects of roasting temperature,roasting time,CO/(CO+CO_(2))composition,and Na_(2)CO_(3) dosage on the boron and iron separation indices were primarily investigated.Under the optimized conditions of the roasting temperature of 850℃,roasting time of 60 min,soda ash dosage of 20 wt%,and CO/(CO+CO_(2)) of 10 vol%,92%of boron was leached during wet grinding,and 88.6%of iron was recovered during the magnetic separation and magnetic concentrate with a total iron content of 61.51 wt%.Raman spectra and^(11)B NMR results indicated that boron exists asB(OH)_(4)^(-) in the leachate,from which high-purity borax pentahydrate could be prepared by CO_(2) carbonation.
基金supported by the National Science and Technology Support Project of China (No.2006BAB01B08)
文摘The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Nirich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi-MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages： deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu-Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies.
基金support from the National Natural Science Foundation of China(Grant Nos.42072305 and 41831293)。
文摘Long-term field monitoring finds that serious surface subsidence can still occur even if the high strength cemented fill method is adopted.Combining the results of numerical simulations with global position system(GPS)monitoring,we took a typical filling mining mine with a steeply inclined ore body as an example,and explored its ground subsidence mechanism.The results show that the ground subsidence caused by the mining of steep ore body is characterized by two settlement centers and a significantly uneven spatial distribution,which is visibly different from ground subsidence characteristic of the coal mine.The subsidence on the hanging wall is much larger than that on the footwall,and the settlement center tends to move to the hanging wall with the increase of mining depth.The backfill improves the strength and surrounding rock bearing capacity,which leads to a lag of about 3 years of the subsidence.However,under the actions of continuous and repeated mining disturbances,the supporting effect of the backfill can only reduce the amplitude of the deformation,but it cannot prevent the occurrence of settlement.
基金Program for New Century Excellent Talents fromUniversity,No.NCET-06-0296
文摘AIM:To explore whether cyclooxygenase 2(COX-2) -765G>C polymorphism is associated with susceptibility of colorectal cancer(CRC)and to evaluate the risk of colorectal cancer in relation to environmental exposures and polymorphism. METHODS:We conducted a case-control study of 137 patients with colorectal cancer and 199 cancer- free controls in northeast China.Multivariate logistic regression analysis was performed to calculate the adjusted odds ratio(OR)and 95% confidence interval (95%CI). RESULTS:The-765G>C polymorphism was not independently associated with CRC risk.However,risk associated with the polymorphism differed by smoking and body mass index(BMI).Smoking and BMI associated risks were stronger among those with-765GG genotype, showing that smokers had a 2.682-fold greater risk of CRC than nonsmokers(51/43 vs 68/126,P=0.006). Compared to those with a normal body mass index(BMI 18.5-22.9),those with overweight(BMI 23-24.9)had a 3.909-fold higher risk of CRC(OR=3.909,95% CI= 2.081-7.344;P<0.001),while those with obesity(BMI >25)had a 2.031-fold higher risk of CRC(OR=1.107, 95% CI=1.107-3.726;P=0.022). CONCLUSION:Although COX-2-765G>C polymorphismis not associated with an increased risk of CRC,-765GG genotype appears to be related to an increased risk in the presence of smoking and higher BMI.
文摘1 Geological Background of Minerlization or Geologic Setting The northeast of Yunnan1 Pb-Zn-Ag-Ge polymetallic ore district is an important part of the southwestern margin of the Yangtze block Sichuan-Yunnan-Guizhou
文摘目的 在高体重指数(body mass index, BMI)率快速增长的情况下,分析1990-2019年中国归因于高BMI的2型糖尿病疾病负担。方法 基于2019年全球疾病负担研究数据,分性别、年龄组分析1990-2019年中国因高BMI造成的2型糖尿病疾病负担,并利用Joinpoint回归模型分析标化后的归因死亡率和归因伤残调整寿命年(disability-adjusted life year, DALY)率的变化趋势。结果 1990-2019年间,我国2型糖尿病患病率从2928.78/10万增至6328.79/10万,归因高BMI的2型糖尿病死亡人数从1.05万增至4.75万,标化死亡率从1.25/10万增至2.39/10万;归因DALY从77.18万人年增至373.76万人年,标化后的归因DALY率从80.21/10万增至181.54/10万,早死损失寿命年(years of life lost, YLL)和伤残损失寿命年(year lived with disability, YLD)及其标化率也呈大幅增长。1990-2019年间,我国归因于高BMI的2型糖尿病标化死亡率和标化DALY率的年平均变化百分比分别为2.28%和2.81%,均有统计学意义(P<0.05),且男性均高于女性。男性标化后的归因DALY率和归因死亡率分别在2010年和2014年超过女性。年龄分层结果显示,50岁以上人群高BMI导致的2型糖尿病疾病负担更加严重,15~49岁人群归因于高BMI的YLD率增幅最大,达到323.99%。结论 1990-2019年间,中国归因于高BMI的2型糖尿病疾病负担显著增加。需加大防控力度,有效管理人群体重指数,并对高危人群采取重点干预,以减轻2型糖尿病疾病负担。
