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Effect of organic mineral supplementation in reducing oxidative stress in Holstein calves during short‑term heat stress and recovery conditions
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作者 A-Rang Son Seon-Ho Kim +3 位作者 Mahfuzul Islam Michelle Miguel Ye Pyae Naing Sang-Suk Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期812-825,共14页
Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)duri... Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)during short-term heat stress(HS)and recovery periods.Eight Holstein calves were randomly assigned to four treatment groups:no mineral supplementation(Con),inorganic minerals(IM),organic minerals(OM),and high-concentration organic minerals(HOM)and two thermal environments(HS and recovery)using 4×2 factorial arrangement in a crossover design of four periods of 35 d.Calves were maintained in a temperature-controlled barn.The experimental period consisted of 14 d of HS,14 d of recovery condititon,and a 7-d washing period.Results Body temperature and respiration rate were higher in HS than in the recovery conditions(P<0.05).Selenium concentration in serum was high in the HOM-supplemented calves in both HS(90.38μg/dL)and recovery periods(102.00μg/dL)(P<0.05).During the HS period,the serum cortisol was 20.26 ng/mL in the HOM group,which was 5.60 ng/mL lower than in the control group(P<0.05).The total antioxidant status was the highest in the OM group(2.71 mmol Trolox equivalent/L),followed by the HOM group during HS,whereas it was highest in the HOM group(2.58 mmol Trolox equivalent/L)during the recovery period(P<0.05).Plasma malondialdehyde and HSP70 levels were decreased by HOM supplementation during the HS and recovery periods,whereas SOD and GPX levels were not significantly affected(P>0.05).The principal coordinate analysis represented that the overall rumen microbiota was not influenced by mineral supplementation;however,temperature-induced microbial structure shifts were indicated(PERMANOVA:P<0.05).At the phylum level,Firmicutes and Actinobacteria decreased,whereas Fibrobacteres,Spirochaetes,and Tenericutes increased(P<0.05),under HS conditions.The genus Treponema increased under HS conditions,while Christensenella was higher in recovery conditions(P<0.05).Conclusion HOM supplementation during HS reduced cortisol concentrations and increased total antioxidant status in Holstein bull calves,suggesting that high organic mineral supplementation may alleviate the adverse effects of HS. 展开更多
关键词 Antioxidant status Heat stress Holstein bull calves Organic mineral supplementation oxidative stress
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Principles of Technology for Bottling Medicinal Mineral Waters of Sairme Using the Example of Source №3a
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作者 Irina Nikolaishvili Giorgi Kvartskava 《American Journal of Analytical Chemistry》 CAS 2024年第4期135-138,共4页
Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sa... Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product. 展开更多
关键词 Sairme mineral Water Deposit oxidation-Reduction Potential Trace Elements Chemical Composition SEASONALITY
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Oxidation of As^Ⅲ by Several Manganese Oxide Minerals in Absence and Presence of Goethite 被引量:3
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作者 FENG Xionghan TAN Wenfeng +2 位作者 LIU Fan Huada Daniel RUAN HE Jizheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第2期249-256,共8页
Oxidation of As^Ⅲ by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thre... Oxidation of As^Ⅲ by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X-ray diffraction (XRD) and transmission electron microscopy (TEM). Three synthesized Mn oxide minerals of different types, birnessite, todorokite, and hausmannite, could actively oxidize As^Ⅲ to Asv, and greatly varied in their oxidation ability. Layer structured birnessite exhibited the highest capacity of As^Ⅲ oxidation, followed by the tunnel structured todorokite. Lower oxide hansmannite possessed much low capacity of As^Ⅲ oxidation, and released more Mn^2+ than birnessite and todorokite during the oxidation. The maximum amount of Asv produced during the oxidation of As^Ⅲ by Mn oxide minerals was in the order: birnessite (480.4 mmol/kg) 〉 todorokite (279.6 mmol/kg) 〉 hansmannite (117.9 mmol/kg). The oxidation capacity of the Mn oxide minerals was found to be relative to the composition, crystallinity, and surface properties. In the presence of goethite oxidation of As^Ⅲ by Mn oxide minerals increased, with maximum amounts of Asv being 651.0 mmol/kg for birnessite, 332.3 mmol/kg for todorokite and 159.4 mmol/kg for hansmannite. Goethite promoted As^Ⅲ oxidation on the surface of Mn oxide minerals through adsorption of the Asv produced, incurring the decrease of Asv concentration in solutions. Thus, the combined effects of the oxidation (by Mn oxide minerals)-adsorption (by goethite) lead to rapid oxidation and immobilization of As in soils and sediments and alleviation of the As^Ⅲ toxicity in the environments. 展开更多
关键词 Mn oxide mineral GOETHITE oxidATION As^Ⅲ ASV
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Provenance Study of Fe–Ti Oxide Minerals in the Quaternary Sediments in Yichang Area and Its Implication of Formation Time of the Yangtze Three Gorges, China 被引量:4
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作者 XIANG Fang DU Wen +3 位作者 HUANG Henxu KANG Dongya ZHU Hongbo FENG Qin 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1598-1608,共11页
The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debata... The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debatable. Fe-Ti oxide minerals are seldom used to study sediment provenance, expecially using scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). In this study, the provenance of Quaternary sediments in Yichang area, which is located to the east of the Yangtze Three Gorges, was investigated by using SEM and EDS to research Fe-Ti oxides. The Panzhihua vanadium titanomagnetite and Emeishan basalt outcrop are located to the west of the Three Gorges. Further, the materials from them are observed in the Quaternary sediments of Yichang area. Fe-Ti oxide minerals from the Huangling granite are observed in the Yunchi and Shanxiyao Formations, which were formed before 0.75 Ma B.P., whereas Fe-Ti oxide minerals from the Huangling granite, Panzhihua vanadium titanomagnetite, and Emeishan basalt are observed in the riverbed and fifth-terrace sediments of the Yangtze River, which were formed after 0.73 Ma B.P.. Thus, we can infer that the Three Gorges formed after the deposition of the Shanxi Formation and before the fifth-terrace; i.e., 0.75-0.73 Ma B.P.. 展开更多
关键词 Yangtze Three Gorges Yichang area Quaternary sediments Fe-Ti oxide minerals China
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Mineralogy of Manganese Oxide Minerals in Iron Manganese Nodules of Several Main Soils in China 被引量:7
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作者 TAN WENFENG LIU FAN +2 位作者 LI YONGHUA HE JIZHENG LI XUEYUAN 《Pedosphere》 SCIE CAS CSCD 2000年第3期265-274,共10页
X-ray diffraction and selective chemical dissolution methods were used to investigate the composition of Mn oxide minerals in Fe-Mn nodules of several main types of soils in China. The changes of relative intensity of... X-ray diffraction and selective chemical dissolution methods were used to investigate the composition of Mn oxide minerals in Fe-Mn nodules of several main types of soils in China. The changes of relative intensity of X-ray diffraction patterns were studied both before and after chemically selective dissolution. It was found that lithiophorite was a common Mn oxide in all examined Fe-Mn nodules. Todorokite, however, was a predominant Mn oxide in Fe-Mn nodules in caf-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn nodules of arp-udic Luvisols in Wuhan and Zaoyang, Hubei Province, contained birnessite and vernadite. Hollandite was found in Fe-Mn nodules of alt-udic Ferrisols of Yizhang, Hunan Province; arp-udic Luvisols of Zaoyang, Hubei Province; and cal-aquic Vertisols of Linyi, Shandong Province. The Fe-Mn nodules in alt-udic Ferrisols of Guiyang, Hunan Province, had a few coronadites. Mineralogy of Mn oxide minerals in soil Fe-Mn nodules was related to soil environment, soil types and quantities of relevant cations. 展开更多
关键词 Fe-Mn nodule Mn oxide minerals soil X-ray difraction
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Flotation of copper oxide minerals:A review 被引量:4
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作者 Qicheng Feng Wenhang Yang +3 位作者 Shuming Wen Han Wang Wenjuan Zhao Guang Han 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第6期1351-1364,共14页
Copper oxide minerals are important copper resources,which include malachite,azurite,chrysocolla,cuprite,etc.Flotation is the most widely used method for the enrichment of copper oxide minerals in the mineral processi... Copper oxide minerals are important copper resources,which include malachite,azurite,chrysocolla,cuprite,etc.Flotation is the most widely used method for the enrichment of copper oxide minerals in the mineral processing industry.In this paper,the surface properties of copper oxide minerals and their effects on the mineral flotation behavior are systematically summarized.The flotation methods of copper oxide minerals and the interaction mechanism with reagents are reviewed in detail.Flotation methods include direct flotation(using chelating reagents or a fatty acid as collector),sulfidization flotation(using xanthate as collector),and activation flotation(using chelating reagents,ammonium/amine salts,metal ions,and oxidant for activation).An effective way to realize efficient flotation of copper oxide minerals is to increase active sites on the surface of copper oxide minerals to enhance the interaction of collector with the mineral surface.Besides,various perspectives for further investigation on the efficient recovery of copper oxide minerals are proposed. 展开更多
关键词 Copper oxide minerals Direct flotation Sulfidization flotation Activation flotation
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The Processing Mineralogy for Lead and Zinc Oxide Ore in Sichuan 被引量:1
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作者 YANG Mei XIAO Wending +2 位作者 YANG Xiang LIANG Dongyun WU Yan 《矿物学报》 CAS CSCD 北大核心 2013年第S1期125-125,共1页
Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxi... Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxide content exceeding the minimum industrial grade and iron ore, total iron content reaches a minimum industrial grade and associated with gold and silver; The mineralogical analysis result shows that lead and zinc mineral composition and configuration are very complexity. The zinc minerals and zinciferous minerals are sphalerite, hemimorphite, Smithsonite, Hydrozincite, zinc chlorite, limonite, zinc dolomite and zincocalcite; lead minerals and plumbiferous minerals are mainly galena, cerussite, anglesite, limonite and Coronadite; The minerals disseminated grain size are very fine and mineral dissemination characteristics are very complex ; expected theoretical recoveries for lead and zinc were 72% and 67% respectively. The results of this study provide basic data and theoretical basis for ore dressing. 展开更多
关键词 lead-zinc oxide ORE PROCESSING mineralOGY material composition DISSEMINATED characteristics OCCURRENCE states
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Chemical Forms of Heavy Metals in Carbonate-Derived Laterite and Enrichment of Its Iron Oxide Minerals 被引量:10
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作者 朱立军 漆亮 《Chinese Journal Of Geochemistry》 EI CAS 1997年第3期263-270,共8页
In this paper the seven-step continuous extracting method was employed in the studyof chemical forms of the six heavy metals Co, Zn, Pb, Cu, Cr and Mn. The result shows thatthe metals in the laterite are present in th... In this paper the seven-step continuous extracting method was employed in the studyof chemical forms of the six heavy metals Co, Zn, Pb, Cu, Cr and Mn. The result shows thatthe metals in the laterite are present in the chemical form of crystalline iron oxides andresidues, and they are transformed toward organic and exchangeable forms in the surface soil.Linear regression analysis indicates that the above heavy metals have a positive correlation withthe crystalline iron oxide minerals. The crystalline iron oxide minerals have a very importantrole to play in the enrichment of heavy metals, especially the solid components in the laterite. 展开更多
关键词 红土 重金属 氧化铁矿物 化学形式
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Characteristics of Lead Sorption on Clay Minerals in Relation to Metal Oxides 被引量:5
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作者 ZHUANGJIE YUGUIRUI 《Pedosphere》 SCIE CAS CSCD 2000年第1期11-20,共10页
Difference of montmorillonite (Mt), illite (It) and kaolinite (Kt) in lead sorption characteristics and the effects of amorphous Fe and Al oxide coatings on the characteristics were experimentally studied with logisti... Difference of montmorillonite (Mt), illite (It) and kaolinite (Kt) in lead sorption characteristics and the effects of amorphous Fe and Al oxide coatings on the characteristics were experimentally studied with logistic model. The sorption curves had sigmoid feature due to use of acetate-type buffer solution. With the model the sorption process could be divided into four stages and the sorption characteristics at the stages were discussed. The results showed that, after Mt, It and Kt were coated by amorphous Fe oxide, their maximum sorption capacity (MSC) and percentage of high-SSC concentration scope (HCS) of Pb2+ increased markedly, but the specific sorption capacity (SSC) decreased. With regard to effects of amorphous Al oxide coating, except for It+AI, the SSC of other samples showed a downtrend, despite that their MSC remained unchanged. Eventually, the gray correlation degrees to Pb2+ sorption for different physicochemical characteristics of the clay minerals were indicated to be higher for hydronium, zero point of surface charge and hydroxy, but lower for specific surface area, density of surface charge and amount of surface charges. 展开更多
关键词 粘土矿物 重金属污染 吸附作用 蒙脱石 伊利石 高岭石 逻辑模型 金属氧化物
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Advance in Matrix Effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing Oxide Minerals 被引量:1
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作者 CUI Yurong TU Jiarun +3 位作者 GENG Jianzhen YE Lijuan ZHOU Hongying LI Huimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第4期1680-1681,共2页
Objective With the development of analytic technologies, in-situ dating on U-bearing oxide minerals (e.g., cassiterite, rutile and baddeleyite) has been widely used in geological chronological researches and has at... Objective With the development of analytic technologies, in-situ dating on U-bearing oxide minerals (e.g., cassiterite, rutile and baddeleyite) has been widely used in geological chronological researches and has attracted remarkable attention to explore evolution of the earth and obtain age information of various geological processes. Matrix effect related studies are especially important during in-situ U- Pb dating based on Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC- ICPMS). However, to our knowledge, only few thorough and systematical matrix effect study of U-bearing oxide minerals has been reported. In this study, we systematically analyzed the matrix effect of U-bearing oxide minerals in order to take place the standards which are difficult to prepare with available standards. 展开更多
关键词 ICPMS ID Pb Advance in Matrix Effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing oxide minerals MC
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Spatial Heterogeneity of Soil Mineral Oxide Components in Depression Between Karst Hills,Southwest China 被引量:9
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作者 DU Hu WANG Kelin +4 位作者 PENG Wanxia ZENG Fuping SONG Tongqing ZHANG Hao LU Shiyang 《Chinese Geographical Science》 SCIE CSCD 2014年第2期163-179,共17页
In karst regions,the spatial heterogeneity of soil mineral oxides and environmental variables is still not clear.We investigated the spatial heterogeneity of SiO2,Al2O3,Fe2O3,CaO,MgO,P2O5,K2O,and MnO contents in the s... In karst regions,the spatial heterogeneity of soil mineral oxides and environmental variables is still not clear.We investigated the spatial heterogeneity of SiO2,Al2O3,Fe2O3,CaO,MgO,P2O5,K2O,and MnO contents in the soils of slope land,plantation forest,secondary forest,and primary forest,as well as their relationships with environmental variables in a karst region of Southwest China.Geostatistics,principal component analysis(PCA),and canonical correlation analysis(CCA)were applied to analyze the field data.The results show that SiO2was the predominant mineral in the soils(45.02%–67.33%),followed by Al2O3and Fe2O3.Most soil mineral oxide components had a strong spatial dependence,except for CaO,MgO,and P2O5in the plantation forest,MgO and P2O5in the secondary forest,and CaO in the slope land.Dimensionality reduction in PCA was not appropriate due to the strong spatial heterogeneity in the ecosystems.Soil mineral oxide components,the main factors in all ecosystems,had greater influences on vegetation than those of conventional soil properties.There were close relationships between soil mineral oxide components and vegetation,topography,and conventional soil properties.Mineral oxide components affected species diversity,organic matter and nitrogen levels. 展开更多
关键词 西南喀斯特地区 主成分分析 空间异质性 中国西南地区 土壤性质 氧化物 矿质 AL2O3微粉
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Characteristics of the Oxide Minerals,Petrophysical and Magnetic Features of Kimberite and Trap in China(Shandong) and Yakyt
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作者 V.K.Garanin 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期208-208,共1页
Aim of the work is to establish the connection between the petrophysical and magnetic features, chemical compositions of microcrystalline oxides, their distribution and the quality of diamonds.In this work author has ... Aim of the work is to establish the connection between the petrophysical and magnetic features, chemical compositions of microcrystalline oxides, their distribution and the quality of diamonds.In this work author has used variety of methods to study these characteristics,including SEM and TMA. Objects—kimberlitic samples from pipes Nurbin (high quantity of diamond)。 展开更多
关键词 CHARACTERISTICS oxide mineralS MICROCRYSTALLINE oxideS
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APPLICATION AND INTERACTION MECHANISMS OF POLYMERIC CARBOHYDRATE IN OXIDES AND SALT-TYPE MINERALS
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作者 李晔 许时 刘奇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第4期43-47,共5页
A systematic analysis has been carried out to investigate the fields of application and interaction mechanism of polymeric carbohydrate, i.e. polysaccharides (including starch, dextrin, cellulose and cellulosic deriva... A systematic analysis has been carried out to investigate the fields of application and interaction mechanism of polymeric carbohydrate, i.e. polysaccharides (including starch, dextrin, cellulose and cellulosic derivatives) on various oxides and salt-type minerals in the article, interaction mechanisms of electrostatic, of hydrogen bonding, and of chemical interaction between polymeric carbohydrate and these minerals are put forward. 展开更多
关键词 polymeric carbohydrate oxideS salt-type minerals interaction mechanisms
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Study on Oxygen Isotope Fractionation in RE Oxide Minerals
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作者 方涛 裘愉卓 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第3期69-72,共4页
The oxygen isotope fractionation equations are calculated for major rare earth oxide minerals by using an increment model. The effects of the variation of RE composition, the isomorphic replacement of Ti 4+ , Nb ... The oxygen isotope fractionation equations are calculated for major rare earth oxide minerals by using an increment model. The effects of the variation of RE composition, the isomorphic replacement of Ti 4+ , Nb 5+ , Ta 5+ , and Th 4+ and the metamictization on the oxygen isotope fractionation in minerals are also discussed. The rare earth oxides are not applicable for geothermometry due to their changeable oxygen isotope fractionation coefficients. 展开更多
关键词 Rare earths Oxygen isotopes RE oxide minerals Fractionation coefficients
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Bioleaching of a kind of alkaline mixed copper oxide and sulphide mineral 被引量:2
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作者 黄明清 吴爱祥 《Journal of Chongqing University》 CAS 2010年第4期177-184,共8页
We conducted two-stage acidification-bioleaching experiments to probe the feasibility of bioleaching for a kind of mixed alkaline copper oxide and sulphide mineral. We used the uniform design method for data analysis ... We conducted two-stage acidification-bioleaching experiments to probe the feasibility of bioleaching for a kind of mixed alkaline copper oxide and sulphide mineral. We used the uniform design method for data analysis and experimental optimization, with initial pH value, pulp density, inoculation of bacteria and ferrous iron concentration selected as the influential factors. Polynomial regression shows that the four factors sequentially influence the copper recovery by 14.430%, 8.555%, 1.982% and 3.895%. Acid equilibrium in the bioleaching system is mainly influenced by alkaline gangue content, chemical reactions and bacterial activity. A maximal portion of refractory copper extracted reaches 71.08%. The dynamic analysis of copper recovery indicates that bioleaching goes through a lag leaching phase, prime leaching phase and leaching stationary phase corresponding to the growth phases of bacteria. Compared with the predicted value of 80.87%, the confirmatory experiment observes a 78.21% copper recovery under the optimal conditions of pH of 1.5, pulp density of 5%, bacteria inoculation of 30% and initial ferrous iron concentration of 9 g L-1. Results suggest that bioleaching is technically feasible to improving total copper recovery. 展开更多
关键词 碱的混合的铜氧化物和硫醚矿物质 BIOLEACHING 一致设计 铜恢复 酸平衡
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Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i>Using FTIR and MALDI-TOF Techniques
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作者 H. Sarvamangala Vinay B. Raghavendra S. T. Girisha 《Journal of Environmental Protection》 2017年第2期194-205,共12页
Biobeneficiation processes involving the separation of valuable minerals from ores and materials using conventional flotation and flocculation methods have been shown to be promising in recent years. There is an enorm... Biobeneficiation processes involving the separation of valuable minerals from ores and materials using conventional flotation and flocculation methods have been shown to be promising in recent years. There is an enormous potential to utilize microorganisms as flocculating agents, flotation collectors and/or depressants. The study involves Biobeneficiation of oxide minerals using Bacillus subtilis. Characterization of minerals (hematite, corundum, calcite and quartz) was carried out through XRD, EDAX and FTIR techniques. FTIR of minerals before and after interaction with cells, cell free extract and extracellular proteins was carried out and it has been found that there is a shift or change in the peaks of functional groups. In presence of protein adsorption, amide peaks were found and in case of polysaccharide adsorption, carboxyl peaks were found which justify the flotation and flocculation results. MALDI-TOF was carried out to confirm the molecular weights of the extracted proteins and it was found that molecular weight of proteins on interaction with minerals was higher than that of uninteracted minerals. 展开更多
关键词 Biobeneficiation FTIR MALDI-TOF Bacillus SUBTILIS oxide minerals
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Preparation of Polymer-Mineral Nanocomposites Based on Vinyl Monomers and Dispersed Inorganic Oxides
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作者 Volodymyr Dutka Yaroslav Kovalskyi +1 位作者 Olena Aksimentyeva Nataliya Oshchapovska 《Advances in Chemical Engineering and Science》 2021年第1期18-28,共11页
The polymer-mineral composites were synthesized using vinyl monomers styrene<span "="" style="font-size:10.5pt;"><span style="font-size:12px;">, methyl acrylate, and buty... The polymer-mineral composites were synthesized using vinyl monomers styrene<span "="" style="font-size:10.5pt;"><span style="font-size:12px;">, methyl acrylate, and butyl acrylate with nano dispersed oxides Fe</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, Cr</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, V</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">5</span></sub><span style="font-size:12px;"> and SiO</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;"> in the presence of benzoyl peroxide and other peroxide initiators. Benzoyl peroxide adsorption on Fe</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, Cr</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, and V</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">5</span></sub><span style="font-size:12px;"> surfaces was studied. The adsorption parameters were found: adsorption-desorption equilibrium constants, maximum adsorption, and the area occupied by the molecule benzoyl peroxide on the surface of the adsorbent. The molecular weights of the polymers in the composites and the degree of grafting of the macromolecules of the polymer to the surface of oxides were studied. It has been found that the surface of the dispersed oxides influences the rate of thermal decomposition of the peroxide initiators and the polymerization parameters of the vinyl monomers.</span></span> 展开更多
关键词 Polymer-mineral Composites Organic Peroxides Radical Polymerization Peroxide Thermal Degradation Metal oxides ADSORPTION Effect of Surface
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Investigation on the deactivation cause of lead-zinc double oxide for the synthesis of diphenyl carbonate by transesterification 被引量:3
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作者 Zhihui Li Yanji Wang +1 位作者 Xiaoshu Ding Xinqiang Zhao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第1期104-109,共6页
The deactivation cause of lead-zinc double oxide for synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol has been investigated. X-ray diffraction (XRD), X-ray pho... The deactivation cause of lead-zinc double oxide for synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol has been investigated. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), thermogravimetry analysis (TG), atomic absorption spectroscopy and elementary analysis are employed for the catalyst characterization. The results show that, the formation of Pb4O(OC6H5)6 through the reaction of phenol and lead species in the catalyst leads to the crystal phase change of active component and serious leaching of lead, which is the cause of the catalyst deactivation. In addition, the composition of the leached lead is ascertained to be a mixture of Pb4O(OC6H5)6 and PbO with the weight percentage of 62.7% and 37.3%, respectively. 展开更多
关键词 lead-zinc double oxide DEACTIVATION dimethyl carbonate TRANSESTERIFICATION diphenyl carbonate organic lead
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Study on experiment and mechanism of thermal dissolved sulfuration of low grade lead-zinc oxide ore in lanpin 被引量:2
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作者 Minghua JIANG Bin YANG +2 位作者 Jijun WU Yuchun ZHAI Yang ZHOU 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第4期291-296,共6页
The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxide... The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxides in the sandstone and ignimbrite are changed into sulfides. The disproportionation reaction of sulfur in a solution is confirmed as 4S+3H2O=2S^2-+S2O3^2--+6H^+. The dynamics process is studied and the first-order reaction rate equation -1n(1-a)=ktt is obtained. The effects of the reactive products, stirring speed, dosage of sulfuration agent, value of pH and sulphidizing temperature on the sulfuration of oxide ore are investigated. The results indicate that the reactive apparent activation energy is 100.8 kJ/mol and the sulfuration ratio of lead-zinc oxide ore reaches 60% under the conditions of pH 5.9-7.5, the sulfuration temperature of 130 ℃, sulfuration time of 180 min and the stirring speed of 800 r/min. 展开更多
关键词 lead-zinc oxides ore Thermal dissolved sulfuration Sulphidizing ratio Disproportionation reaction First-order reaction
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Antioxidant capacity and concentration of redox-active trace mineral in fully weaned intra-uterine growth retardation piglets 被引量:6
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作者 Hao Zhang Yue Li Tian Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第2期201-207,共7页
Background: The redox status of intra-uterine growth retardation(IUGR) piglets post-weaning has been poorly studied.Methods: Newborns from twenty-four sows were weighted, weaned at 21 d and fed a starter diet unti... Background: The redox status of intra-uterine growth retardation(IUGR) piglets post-weaning has been poorly studied.Methods: Newborns from twenty-four sows were weighted, weaned at 21 d and fed a starter diet until sampling.Sampling was done at 14 d post-weaning. A piglet was defined as IUGR when its birth weight was 2 SD below the mean birth weight of the total population. At weaning, eighteen piglets with nearly equal body weight from each category(i.e. IUGR or normal birth weight(NBW) piglets) were selected and then allocated to two treatments,consisted of six replicates with each pen having three piglets.Results: Compared with NBW group, IUGR significantly decreased average daily gain(P 〈 0.001), average daily feed intake(P = 0.003), and feed efficiency(P 〈 0.001) of piglets during the first two weeks post-weaning. IUGR decreased the activities of total antioxidant capacity(P = 0.019), total superoxide dismutase(T-SOD, P = 0.023),and ceruloplasmin(P = 0.044) but increased the levels of malondialdehyde(P = 0.040) and protein carbonyl(P = 0.010) in plasma. Similarly, the decreased activities of T-SOD(P = 0.005), copper- and zinc-containing superoxide dismutase(Cu/Zn-SOD, P = 0.002), and catalase(P = 0.049) was observed in the liver of IUGR piglets than these of NBW piglets. IUGR decreased hepatic Cu/Zn-SOD activity(P = 0.023) per unit of Cu/Zn-SOD protein in piglets when compared with NBW piglets. In addition, IUGR piglets exhibited the decreases in accumulation of copper in both plasma(P = 0.001) and liver(P = 0.014), as well as the concentrations of iron(P = 0.002) and zinc(P = 0.048) in liver. Compared with NBW, IUGR down-regulated m RNA expression of Cu/Zn-SOD(P = 0.021) in the liver of piglets.Conclusions: The results indicated that IUGR impaired antioxidant capacity and resulted in oxidative damage in fully weaned piglets, which might be associated with the decreased levels of redox-active trace minerals. This study highlights the importance of redox status in IUGR offspring and provides a rationale for alleviating oxidative damage by dietary interventions aiming to supplement trace minerals and to restore redox balance in the future. 展开更多
关键词 Antioxidant capacity Intra-uterine growth retardation oxidative damage Piglet Redox-active trace mineral
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