X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of ...X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of moderately thermophilic bacteria (45 °C). Results show that monosulfide (CuS), disulfide (S22?), polysulfide (Sn2?), elemental sulfur (S0) and sulfate (SO42?) are the main intermediate species on the surface of chalcopyrite during bioleaching byA. caldus,S. thermosulfidooxidans andL. ferriphilum. The low kinetics of dissolution of chalcopyrite inA. caldus can be mainly attributed to the incomplete dissolution of chalcopyrite and the passivation layer of polysulfide. Polysulfide and jarosite should be mainly responsible for the passivation of chalcopyrite in bioleaching byL. ferriphilumorS. thermosulfidooxidans. However, elemental sulfur should not be the main composition of passivation layer of chalcopyrite during bioleaching.展开更多
The research analyzed status quo of Chinese tea export, including export scale, exporting countries and regions, product structure, explored factors affecting tea export, and detailed international trade development o...The research analyzed status quo of Chinese tea export, including export scale, exporting countries and regions, product structure, explored factors affecting tea export, and detailed international trade development of Chinese teas. On basis of global politics and economic situations, the research proposed new thoughts and of global trades of Chinese teas with application of the Belt and Road Initiative strategy.展开更多
Low market share, small scale, inappropriate product structure, relativelyhigh market concentration, and heavy dependence on Asian markets such as Japan and Korea are some ofthe characteristics of the current exportat...Low market share, small scale, inappropriate product structure, relativelyhigh market concentration, and heavy dependence on Asian markets such as Japan and Korea are some ofthe characteristics of the current exportation status of traditional Chinese medicinal materials(TCMM). The profound reasons for these problems lie in the cultural, technological and informativebarriers between TCMM and the international market as well as the underdevelopment of TCMMmodernization. Therefore, measures should be taken to enhance the cultural exchange and strategiccooperation in TCMM marketing with international organizations, implement a standardization of TCMM,establish information sharing and other supporting mechanisms, and accelerate TCMM modernizationand innovation.展开更多
Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated ...Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated that the copper extraction at pH 1.5 was 1.5 and 1.4 times that at pH 1.0 and pH 2.0 respectively. The copper extraction obtained at 45 ℃ was 1236.8%higher than that at 50 ℃. With the increase of rotation speed or the decrease of liquid volume, copper extraction was improved obviously. Copper extraction was improved gradually with the increase of pyrite ratio. However, when the ratio was higher than 20.0%, no further increase in copper extraction was observed. And the statistically significant interactive effects on copper extraction were found between temperature and pH, and temperature and pyrite ratio.展开更多
AIM: To evaluate the aetiology, clinical outcome and factors related to mortality of acute upper gastrointestinal bleeding (AUGIB) in octogenarians. METHODS: We reviewed the records of all patients over 65 years old w...AIM: To evaluate the aetiology, clinical outcome and factors related to mortality of acute upper gastrointestinal bleeding (AUGIB) in octogenarians. METHODS: We reviewed the records of all patients over 65 years old who were hospitalised with AUGIB in two hospitals from January 2006 to December of 2006. Patients were divided into two groups: Group A (65-80 years old) and Group B (> 80 years old). RESULTS: Four hundred and sixteen patients over 65 years of age were hospitalized because of AUGIB. Group A included 269 patients and Group B 147 patients. Co-morbidity was more common in octogenarians (P = 0.04). The main cause of bleeding was peptic ulcer in both groups. Rebleeding and emergency surgery were uncommon in octogenarians and not different from those in younger patients. In-hospital complications were more common in octogenarians (P = 0.05) and more patients died in the group of octogenarians compared to the younger age group (P = 0.02). Inability to perform endoscopic examination (P = 0.002), presence of high risk for rebleeding stigmata (P = 0.004), urea on admission (P = 0.036), rebleeding (P = 0.004) and presenceof severe co-morbidity (P < 0.0001) were related to mortality. In multivariate analysis, only the presence of severe co-morbidity was independently related to mortality (P = 0.032). CONCLUSION: While rebleeding and emergency surgery rates are relatively low in octogenarians with AUGIB, the presence of severe co-morbidity is the main factor of adverse outcome.展开更多
Bioleaching experiments combined with X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)and scanning electron microscopy(SEM)were conducted to investigate three kinds of bornites from different regions leach...Bioleaching experiments combined with X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)and scanning electron microscopy(SEM)were conducted to investigate three kinds of bornites from different regions leached by moderately thermophilic mixed bacteria of Leptospirillum ferriphilum YSK,Acidithiobacillus caldus D1 and Sulfobacillus thermosulfidooxidans ST.The results of bioleaching experiments showed that the leaching efficiency and the redox potential were significantly increased.The copper extraction efficiencies of three kinds of bornite maintained rapid growth until around the 12th day and no longer increased after the 18th,reaching 83.7%,96.5%and 86.6%,respectively.The XRD results of the leaching residue indicated that three kinds of bornites all produced jarosite in the late stage of leaching,and the leaching residues from of Daye Museum and Yunnan Geological Museum contained a mass of elemental sulfur.XPS analysis and scanning electron microscopy experiments showed that the surface of mineral particles was jarosite and the copper in the leaching residue was almost dissolved.展开更多
Hepatocellular carcinoma (HCC) is the fish most common cancer in the world. This case documents an unusual metastatic presentation of HCC in the humerus. Preoperative palliative arterial embolization of the tumor wa...Hepatocellular carcinoma (HCC) is the fish most common cancer in the world. This case documents an unusual metastatic presentation of HCC in the humerus. Preoperative palliative arterial embolization of the tumor was performed to arrest severe tumor bleeding caused by the biopsy. Embolization turned out to be useful also in limiting/preventing potential uncontrolled bleeding during subsequent amputation.展开更多
Hundreds of scientific journals are published in China. However, only scores of them are included in Science Citation Index by the Institute for Scientific Information, with impact factors of only 1 or less. Thus, how...Hundreds of scientific journals are published in China. However, only scores of them are included in Science Citation Index by the Institute for Scientific Information, with impact factors of only 1 or less. Thus, how to establish a first-class international scientific journal in China is an important but difficult topic that deserves extensive exploration. World Journal of Gastroenterology (WJG) sets a good example although it has experienced setbacks on the road towards success. Concepts and pursuits that affirm the overall development direction, innovation and dreams that provide impetus and aspiration for higher objectives, team work and unique pattern that assure excellent quality and service, and culture and environment that also determine the speed and direction of the development, are believed to be the major factors contributing to the success of WJG. It is recommended that the effective resolution to the above issue is to learn from Chinese examples such as WJG rather than from “how foreign journals do”.展开更多
基金Projects(51374248,51320105006)supported by the National Natural Science Foundation of ChinaProject(NCET-13-0595)supported by the Program for New Century Excellent Talents in University,ChinaProject(2014T70692)supported by China Postdoctoral Science Foundation
文摘X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of moderately thermophilic bacteria (45 °C). Results show that monosulfide (CuS), disulfide (S22?), polysulfide (Sn2?), elemental sulfur (S0) and sulfate (SO42?) are the main intermediate species on the surface of chalcopyrite during bioleaching byA. caldus,S. thermosulfidooxidans andL. ferriphilum. The low kinetics of dissolution of chalcopyrite inA. caldus can be mainly attributed to the incomplete dissolution of chalcopyrite and the passivation layer of polysulfide. Polysulfide and jarosite should be mainly responsible for the passivation of chalcopyrite in bioleaching byL. ferriphilumorS. thermosulfidooxidans. However, elemental sulfur should not be the main composition of passivation layer of chalcopyrite during bioleaching.
文摘The research analyzed status quo of Chinese tea export, including export scale, exporting countries and regions, product structure, explored factors affecting tea export, and detailed international trade development of Chinese teas. On basis of global politics and economic situations, the research proposed new thoughts and of global trades of Chinese teas with application of the Belt and Road Initiative strategy.
文摘Low market share, small scale, inappropriate product structure, relativelyhigh market concentration, and heavy dependence on Asian markets such as Japan and Korea are some ofthe characteristics of the current exportation status of traditional Chinese medicinal materials(TCMM). The profound reasons for these problems lie in the cultural, technological and informativebarriers between TCMM and the international market as well as the underdevelopment of TCMMmodernization. Therefore, measures should be taken to enhance the cultural exchange and strategiccooperation in TCMM marketing with international organizations, implement a standardization of TCMM,establish information sharing and other supporting mechanisms, and accelerate TCMM modernizationand innovation.
基金Project (2012zzts026) supported by the Fundamental Research Funds for the Central Universities,ChinaProject (201205020) supported by Scientific Research Program of Marine Public Welfare Industry of China+2 种基金Project (51074195) supported by the National Natural Science Foundation of ChinaProject (CX2012B123) supported by Research Innovation for Graduate Student of Hunan Province,ChinaProject (12C517) supported by Education Department of Hunan Province,China
文摘Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated that the copper extraction at pH 1.5 was 1.5 and 1.4 times that at pH 1.0 and pH 2.0 respectively. The copper extraction obtained at 45 ℃ was 1236.8%higher than that at 50 ℃. With the increase of rotation speed or the decrease of liquid volume, copper extraction was improved obviously. Copper extraction was improved gradually with the increase of pyrite ratio. However, when the ratio was higher than 20.0%, no further increase in copper extraction was observed. And the statistically significant interactive effects on copper extraction were found between temperature and pH, and temperature and pyrite ratio.
文摘AIM: To evaluate the aetiology, clinical outcome and factors related to mortality of acute upper gastrointestinal bleeding (AUGIB) in octogenarians. METHODS: We reviewed the records of all patients over 65 years old who were hospitalised with AUGIB in two hospitals from January 2006 to December of 2006. Patients were divided into two groups: Group A (65-80 years old) and Group B (> 80 years old). RESULTS: Four hundred and sixteen patients over 65 years of age were hospitalized because of AUGIB. Group A included 269 patients and Group B 147 patients. Co-morbidity was more common in octogenarians (P = 0.04). The main cause of bleeding was peptic ulcer in both groups. Rebleeding and emergency surgery were uncommon in octogenarians and not different from those in younger patients. In-hospital complications were more common in octogenarians (P = 0.05) and more patients died in the group of octogenarians compared to the younger age group (P = 0.02). Inability to perform endoscopic examination (P = 0.002), presence of high risk for rebleeding stigmata (P = 0.004), urea on admission (P = 0.036), rebleeding (P = 0.004) and presenceof severe co-morbidity (P < 0.0001) were related to mortality. In multivariate analysis, only the presence of severe co-morbidity was independently related to mortality (P = 0.032). CONCLUSION: While rebleeding and emergency surgery rates are relatively low in octogenarians with AUGIB, the presence of severe co-morbidity is the main factor of adverse outcome.
基金Project(51974363)supported by the National Natural Science Foundation of China。
文摘Bioleaching experiments combined with X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)and scanning electron microscopy(SEM)were conducted to investigate three kinds of bornites from different regions leached by moderately thermophilic mixed bacteria of Leptospirillum ferriphilum YSK,Acidithiobacillus caldus D1 and Sulfobacillus thermosulfidooxidans ST.The results of bioleaching experiments showed that the leaching efficiency and the redox potential were significantly increased.The copper extraction efficiencies of three kinds of bornite maintained rapid growth until around the 12th day and no longer increased after the 18th,reaching 83.7%,96.5%and 86.6%,respectively.The XRD results of the leaching residue indicated that three kinds of bornites all produced jarosite in the late stage of leaching,and the leaching residues from of Daye Museum and Yunnan Geological Museum contained a mass of elemental sulfur.XPS analysis and scanning electron microscopy experiments showed that the surface of mineral particles was jarosite and the copper in the leaching residue was almost dissolved.
文摘Hepatocellular carcinoma (HCC) is the fish most common cancer in the world. This case documents an unusual metastatic presentation of HCC in the humerus. Preoperative palliative arterial embolization of the tumor was performed to arrest severe tumor bleeding caused by the biopsy. Embolization turned out to be useful also in limiting/preventing potential uncontrolled bleeding during subsequent amputation.
文摘Hundreds of scientific journals are published in China. However, only scores of them are included in Science Citation Index by the Institute for Scientific Information, with impact factors of only 1 or less. Thus, how to establish a first-class international scientific journal in China is an important but difficult topic that deserves extensive exploration. World Journal of Gastroenterology (WJG) sets a good example although it has experienced setbacks on the road towards success. Concepts and pursuits that affirm the overall development direction, innovation and dreams that provide impetus and aspiration for higher objectives, team work and unique pattern that assure excellent quality and service, and culture and environment that also determine the speed and direction of the development, are believed to be the major factors contributing to the success of WJG. It is recommended that the effective resolution to the above issue is to learn from Chinese examples such as WJG rather than from “how foreign journals do”.