检索结果-南通市图书馆

1,3-氧硫戊环为受体的Hg^(2+)荧光探针的设计、合成及性能

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

光谱学与光谱分析 2024年第7期44卷 1913-1917页

作者：梁庆祥周五吴爱斌舒文明余维初长江大学化学与环境工程学院化学系湖北荆州434023 长江大学非常规油气协同创新中心湖北荆州434023 油气田清洁生产与污染物控制湖北省工程研究中心湖北荆州434023

Hg^(2+)是毒性最强的重金属离子之一,会造成空气、土壤和水的污染,严重损害人体健康,开发有效的分析方法检测环境体系中的Hg^(2+)尤为重要。荧光探针因其灵敏度高、选择性好、响应速度快、可实时在线检测等优点,已广泛应用于Hg^(2+)检... 详细信息

Hg^(2+)是毒性最强的重金属离子之一,会造成空气、土壤和水的污染,严重损害人体健康,开发有效的分析方法检测环境体系中的Hg^(2+)尤为重要。荧光探针因其灵敏度高、选择性好、响应速度快、可实时在线检测等优点,已广泛应用于Hg^(2+)检测。以Hg^(2+)促进硫代缩醛的去保护反应设计合成了一种全新的以1,3-氧硫戊环为受体的开启型Hg^(2+)荧光探针[2-(pyren-1-yl)-1,3-oxathiolane,POX],通过^(1)H NMR、^(13)C NMR和HRMS对POX结构进行表征,考察了POX在CH_(3)CH_(2)OH/H_(2)O中对Hg^(2+)的选择性、竞争性、浓度滴定、pH滴定、时间依赖性、检出限和识别机理等。研究结果表明,POX可在较宽的pH范围内对Hg^(2+)快速识别,并表现出高度的选择性和灵敏度;向POX中加入Hg^(2+)后,在386 nm处出现明显的荧光发射峰,表明POX对Hg^(2+)呈现出显著的荧光“开启”效应,其识别过程几乎不受其他金属离子干扰;荧光滴定实验表明POX在Hg^(2+)浓度为0~6.5μmol·L^(-1)范围内具有良好的线性响应(R^(2)=0.9994),检出限为0.168μmol·L^(-1),在实际水样中检测Hg^(2+)的RSD小于2.92%。由于POX合成简单、原料易得且pH适用范围较广,可作为定性和定量检测环境中Hg^(2+)的潜在工具。

关键词：荧光探针 Hg^(2+) 1,3-氧硫戊环荧光开启

Microstructure Characteristic and Phase Evolution of Refractory Siderite Ore during Sodium-carbonate-added Catalyzing Carbothermic Reduction

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2016年第9期23卷 891-899页

作者： Shao-jun BAI Meng WU Chao LU shu-ming wen State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming 650093Yunnan China Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China

Thermodynamic analysis of refractory siderite ore during carbothermic reduction was conducted. Micro- structure characteristics and phase transformation of siderite ore during sodium-carbonate-added catalyzing carboth- ermic reduction were investigated. X-ray diffraction （XRD）, scanning electron microscopy and energy-dispersive analysis of X rays were used to characterize the reduced samples. Results indicate that the solid reaction between FeO and SiO2 is inevitable during carbothermic reduction and the formation of fayalite is the main hindrance to the rapid reduction of siderite. The phase transformation of present siderite ore can be described as： siderite-magnetite-metallic iron, complying with the formation of abundant fayalite. Improving the reduction temperature （-1050 -C ） and duration is helpful for the formation and aggregation of metallic iron. The iron particle size in the reduced ore was below 20 l-m, and fayalite was abundant in the absence of sodium carbonate. With 5% Na2CO3 addition, the iron particle size in the reduced ore was generally above 50μm, and the diffraction intensity associated with metallic iron in the XRD pattern increased. The Na2O formed from the dissociation of Na2 CO3 can catalyze the carbothermie reduction of the siderite. This catalytic activity may be mainly caused by an increase in the reducing reaction activity of FeO.

关键词： siderite ore microstructure characteristic phase evolution catalyzing carbothermie reduction

A novel method for improving cerussite sulfidization

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 609-617页

作者： Qi-cheng Feng shu-ming wen wen-juan Zhao Qin-bo Cao Chao Lü State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Kunming Metallurgical Research Institute

Evaluation of flotation behavior, solution measurements, and surface analyses were performed to investigate the effects of chloride ion addition on the sulfidization of cerussite in this study. Micro-flotation tests indicate that the addition of chloride ions prior to sulfidization can significantly increase the flotation recovery of cerussite, which is attributed to the formation of more lead sulfide species on the mineral surface. Solution measurement results suggest that the addition of chloride ions prior to sulfidization induces the transformation of more sulfide ions from pulp solution onto the mineral surface by the formation of more lead sulfide species. X-ray diffraction and energy-dispersive spectroscopy indicate that more lead sulfide species form on the mineral surface when chloride ions are added prior to sulfidization. These results demonstrate that the addition of chloride ions prior to sulfidization can significantly improve the sulfidization of cerussite, thereby enhancing the flotation performance.

关键词： cerussite sulfidization chloride surface analysis

Mineral phase reconstruction behavior of direct reduction and smelting titanium slag at high temperature and slow cooling

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2015年第6期34卷 440-444页

作者： Yi-Jie Wang shu-ming wen Qi-Cheng Feng Zhi-wen Ye Min Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Faculty of Land Resource Engineering Kunming University of Science and Technology Advanced Analysis and Measurement Center Yunnan University

Titanium slag in this study was produced by subjecting titanomagnetite concentrate to direct reductionelectric furnace smelting. Processing mineralogy and mineral phase reconstruction behavior at high temperature and slow cooling treatment were examined by chemical analysis, X-ray diffraction （XRD）, optical microscopy （OM）, scanning electron microscopy （SEM）, and energydispersive spectroscopy （EDS）. Anosovite solid solution is the main titanium product by the direct reduction and smelting process. Results of slow-cooling experiments show that crystal volume and size increase as cooling rate decreases. Anosovite and gangue mineral crystals develop fully with large crystal volume and size at a cooling rate of 2 ***-1. Moreover, the growth of anosovite crystal was characterized by crystal nucleation and growth theory. These results provide further insights into the separation of anosovite from gangue by mineral processing.

关键词： Direct reduction Smelting titanium slag Anosovite Slow cooling Crystal

Extracting copper from copper oxide ore by a zwitterionic reagent and dissolution kinetics

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 241-248页

作者： Jiu-shuai Deng shu-ming wen Jian-ying Deng Dan-dan Wu State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology

Sulfamic acid （SA）, which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leach- ing were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reac- tion temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate miner- als of copper, zinc, cobalt and so on in an SA system.

关键词： malachite copper extraction sulfamic acid dissolution kinetics

First-principle study on the surface atomic relaxation properties of sphalerite

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 775-781页

作者： Jian Liu shu-ming wen Yong-jun Xian Shao-jun Bai Xiu-min Chen Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China National Engineering Laboratory of Vacuum Metallurgy Kunming University of Science and Technology Kunming 650093 China

The surface properties of sphalerite （ZnS） were theoretically investigated using first principle calculations based on the density functional theory （DFT）. DFT results indicate that both the （110） and the （220） surfaces of sphalerite undergo surface atom relaxation after geometry optimization, which results in a considerable distortion of the surface region. In the normal direction, i.e., perpendicular to the sur- face, S atoms in the first surface layer move outward from the bulk （dl）, whereas Zn atoms move toward the bulk （d2）, forming an S-enriched surface. The values of these displacements are 0.003 nm for dl and 0.021 nm for d2 on the （110） surface, and 0.002 nm for dl and 0.011 nm for d2 on the （220） surface. Such a relaxation process is visually interpreted through the qualitative analysis of molecular mechanics. X-ray photoelectron spectroscopic （XPS） analysis provides the evidence for the S-enriched surface. A polysulphide （S n^2- ） surface layer with a bind- ing energy of 163.21 eV is formed on the surface of sphalerite after its grinding under ambient atmosphere. This S-enriched surface and the S 2- surface layer have important influence on the flotation properties ofsphalerite. Keywords：

关键词： sphalerite surface relaxation density fimctional theory froth flotation

Zn release from fluid inclusions in a natural sphalerite

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 420-426页

作者： shu-ming wen Jian Liu Bo Li Run-sheng Han Yi Zhang Jiu-shuai Deng Faculty of Land Resource Engineering Kunming University of Science and Technology Southwest Institute of Geological Survey Center for Non-ferrous Mineral Resources Kunming University of Science and Technology

The type, size, and compositions of fluid inclusions in a natural sphalerite were investigated and the total concentration of Zn released from the fluid inclusions was measured. To compare the total concentration of Zn released from the fluid inclusions with that dissolved from the sphalerite itself, dissolution experiments and theoretical calculations for the dissolution equilibrium of the sphalerite were also performed. The results indicate that large numbers of fluid inclusions with various sizes exist in the sphalerite, which can be divided into four types, i.e., pure gaseous inclusions, pure liquid inclusions, gas-liquid inclusions, and gas-liquid inclusions containing solid minerals. These inclusions were broken open during the grinding process, and their compositions were released to the solution. The total concentration of Zn released from these inclusions reaches 18.35×10^-6 mol/L, which is much higher than that of Zn dissolved from the sphalerite itself （1.93×10^-6 mol/L） and the theoretical calculation value （2.73×10^-8 mol/L）.

关键词： zinc ore treatment sphalerite fluid inclusions flotation

Effect of lattice defects on the electronic structures and floatability of pyrites

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1069-1076页

作者： Yong-jun Xian shu-ming wen Xiu-ming CHen Jiu-shuai Deng Jian Liu Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China National Engineering Laboratory of Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China

The electronic structures of three types of lattice defects in pyrites （i.e., As-substituted, Co-substituted, and intercrystalline Au py-rites） were calculated using the density functional theory （DFT）. In addition, their band structures, density of states, and difference charge density were studied. The effect of the three types of lattice defects on the pyrite floatability was explored. The calculated results showed that the band-gaps of pyrites with Co-substitution and intercrystalline Au decreased significantly, which favors the oxidation of xanthate to dix-anthogen and the adsorption of dixanthogen during pyrite flotation. The stability of the pyrites increased in the following order： As-substituted 〈 perfect 〈 Co-substituted 〈 intercrystalline Au. Therefore, As-substituted pyrite is easier to be depressed by intensive oxidi-zation compared to perfect pyrite in a strongly alkaline medium. However, Co-substituted and intercrystalline Au pyrites are more difficult to be depressed compared to perfect pyrite. The analysis of the Mulliken bond population and the electron density difference indicates that the covalence characteristic of the S Fe bond is larger compared to the S S bond in perfect pyrite. In addition, the presence of the three types of lattice defects in the pyrite bulk results in an increase in the covalence level of the S Fe bond and a decrease in the covalence level of the S S bond, which affect the natural floatability of the pyrites.

关键词： pyrites lattice defects density functional theory electronic structure flotation

Existence and release of fluid inclusions in bornite and its associated quartz and calcite

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 815-822页

作者： Jiu-shuai Deng shu-ming wen Dan-dan Wu Jian Liu Xiao-lin Zhang Hai-ying Shen Faculty of Land Resource Engineering Kunming University of Science and Technology Faculty of Foreign Languages & Cultures Kunming University of Science and Technology

The existence and release of fluid inclusions in bornite and its associated minerals, namely, quartz and calcite were investigated and confirmed. The structures, forms, and phases of these large quantities of fluid inclusions were also studied. A mass of fluid inclusions with various sizes, distributions, shapes, and phases exist in bornite and its associated minerals. Their sizes vary from a few micrometers to tens of micrometers, and the forms appear as negative crystals, or elongated, elliptical, and irregular. At room temperature, fluid inclusions were mainly characterized as gas-liquid two- phase. However, small amounts of fluid inclusions with pure gas phase and pure liquid single-phase were also observed in quartz and calcite. These fluid inclusions initially broke during the ore crushing and grinding process and then released into the flotation pulp in the flotation process. The quantitative analysis of fluid inclusions in the solution and the comparisons of mineral dissolution show that the amount of copper and iron released by fluid inclusions in the bornite sample is higher than the amount dissolved by the mineral; fluid inclusions in the associated gangue minerals, quartz, and calcite also make contribution.

关键词： flotation fluid inclusions bornite quartz calcite