金云母蛭石间层矿物的酸浸取物与酸蚀机理研究

对采自新疆尉犁蛭石矿的金云母蛭石间层矿物样品进行了酸处理实验研究。在样品化学成分和XRD分析的基础上,研究了样品酸处理后酸浸取物的化学组成、含量及结构变化特征;分析讨论了金云母蛭石间层矿物在酸处理过程中不同阳离子浸出率的变化规律和酸蚀机理。结果表明,层间可交换性阳离子的氧化物CaO和Na2O的酸浸取率最高,层间不可交换性阳离子的氧化物K2O次之,八面体中阳离子的氧化物MgO、Fe2O3和Al2O3具有较高的酸浸取率,而四面体阳离子的氧化物Si O2的酸浸取率最低;金云母蛭石间层矿物中蛭石晶层含量高的样品酸浸取率高,金云母蛭石间层矿物的耐酸蚀性能不如金云母。

苹果、杨树等林木根系浸取物对小麦生长的潜在影响

从化学生态学的角度，了解树木根系对农作物生长的影响，针对泡桐树（Ｐａｕｌｏｗｎｉａｅｌｏｎｇａｔａ）、苹果树（Ｍａｌｕｓｐｕｍｉｌａ）、桃树（Ｐｒｕｎｕｓｐｅｒｓｉｃａ）和杨树（Ｐｏｐｕｌｕｓｃａｎａｄｅｎｓｉｓ）进行了实验。本文给出了实验结果。实验表明，泡桐根、苹果根、杨树根和桃树根的水浸液抑制小麦的种子萌发，抑制强度依次为：桃根＞杨树根＞苹果树根＞泡桐根。树根水浸液同样抑制小麦幼苗根伸长。其作用强度为：杨树根＞苹果树根＞泡桐树根。根水浸液再用乙醚萃取，乙醚萃取液表现了更为明显的对小麦早期根和苗发育的抑制作用。抑制能力为：桃树根＞杨树根＞苹果树根＞泡桐树根。苹果树根的根皮苷在土壤中或水中可依次降解产生根皮素，对羟基氢化肉桂酸，对羟基苯甲酸和间苯三酚。以此为例，取化学试剂对羟基苯甲酸和间苯三酚进行小麦种子萌发和早期发育试验。结果表明，当化合物浓度为１×１０－２Ｍ时，可抑制小麦种子萌发和生长。在实验样地的土壤中检出了对羟基苯甲酸，这表明存在林木根系产生化学物质而影响作物生长的可能性。本文还分析了不利影响发生的条件。

黑龙江省四种老鹳草乙醇浸出物和鞣质含量测定

本文采用络合量法对黑龙江省的老鹳草(Geranium Wilfordii Maxim.)、鼠掌老鹳草(G.Sibiricum L.)、粗根老鹳草(G. Dahuricum DC.)、毛蕊老鹳草(G.Platyanthum duthie.)中鞣质含量进行测定，同时还测定了其乙醇浸取物的含量。结果表明：其鞣质含量和乙醇浸取物含量分别为老鹳草(3.865%，10.38%)、鼠掌老鹳草(2.924%，8.382%)、粗根老鹳草(6.639%，12.89%)、毛蕊老鹳草(7.817%，13.48%)，为制定老鹳草的质量标准提供了科学资料。

银纳米粒子生物催化合成的研究进展

综述了银纳米粒子生物催化合成的研究进展,重点阐述了以微生物(细菌、真菌、酵母和链霉菌)、植物浸取液(多酚类化合物和植物蛋白质)和酶(硝酸还原酶、辣根过氧化物酶和磷酸酶)等为催化剂或还原剂合成纳米银生物的方法,并对其未来发展进行了展望。参考文献51篇。

钼矿石中氧化钼的浸取条件研究

以Cu^(2+)-稀HCl混合溶液为MoO_3的选择性溶剂,Cu^(2+)能有效地消除酸溶硫化物溶解时产生的H_2S对MoO_3测定的干扰。选用催化极谱法测Mo可进一步简化操作手续,提高测定灵敏度。所拟方法用于一般钼矿石物相分析,尤其对含酸溶硫化物较多的矿石均能得到满意的结果。

茶饼皂甙配制洗发液的研究

依据国家化妆品标准所要求的洗发液浓度、粘度、泡沫３项较为重要指标，对茶饼皂甙进行乙醇溶剂浸提，并对浸取物进行测定，给出初步配方，为茶饼皂甙洗发液的实际配方提供参考。

十四烷基二甲基苄基氯化铵萃取Au(CN)_2^-的微观机理

通过萃取平衡、傅里叶变换红外光谱及分峰技术研究了季铵盐十四烷基二甲基苄基氯化铵 ( TDM-BAC) -磷酸三丁酯 ( TBP) -正庚烷体系萃取 Au( CN) - 2 的机理及过程 .提出了萃合物的结构模型是基于氢键的超分子体系 ,组成为 [R4N+]· [Au( CN) - 2 ]· 4 H2 O· 4 TBP.当有机相金浓度大于 3g·L- 1 时 ,有机相中存在聚集现象 .通过激光光散射技术测定了有机相中反向胶团的大小 ,表明萃取过程是分散在水相中的胶团在协萃剂 (或助表面活性剂 )作用下溶入有机相 ,转型为反向胶团或微乳液 ( W/O型 )聚集状态 .

Decomposition mechanism of pentlandite during electrochemical bio-oxidation process

Electrochemical measurements were carried out to elucidate decomposition mechanism of pentlandite using modified powder microelectrode with Acidithiobacillus ferrooxidans attached or without on the mineral powder surface.Cyclic voltammetry（CV） results show that at a low potential of about-0.2 V（vs SCE）,the pentlandite was transformed to an intermediated phase like Fe4.5-yNi4.5-xS8-z when Fe and Ni ions were evacuated from mineral lattice;when the potential was changed from-0.2 V to 0.2 V,the unstable violarite（Fe3Ni3S4） and FeNi2S4 were formed which was accompanied by element sulfur formed on the mineral surface;when the potential increased over 0.2 V,the unstable intermediated phase decomposed entirely;at a higher potential of 0.7 V,the evacuated ferrous ion was oxidized to ferric ion.The presence of Acidithiobacillus ferrooxidans made the oxidation peak current increase with initial peak potential negatively moving,and the bacteria also contributed to the sulfur removing from mineral surface,which was demonstrated by the reduction characteristic at potential ranging from-0.75 to-0.5 V.Leaching experiments and electrochemical results show that the solution acidity increasing when pH2 may impede the oxidation process slightly.

Enrichment of ferric iron on mineral surface during bioleaching of chalcopyrite

In order to investigate the enrichment of ferric iron bound by extracellular polymeric substance （EPS） on the mineral surface during bioleaching of chalcopyrite, several methods including sonication, heating and vortexing were used and sonication at 48℃ was shown as a good way to extract ferric iron. Scanning electron microscope （SEM） and energy dispersive X-ray spectrometer （EDX） analysis showed that lots of cracks and pits can be found on the chalcopyrite surface after bioleaching and that iron oxide was filled in these cracks and pits. The variations of contents of ferric iron and EPS on the chalcopyrite surface were investigated. The results indicated that the content of EPS increased rapidly in the first 10 d and then maintained at a stable level, while ferric iron content increased all the time, especially in the later stage of bioleaching.

Microbial extraction of nickel from chromite overburdens in the presence of surfactant

The effect of surfactant polyoxyethylenesorbitan monolaurate （Tween-20） on the nickel bioleaching from pre-treated chromite overburden （COB）, Sukinda with fungal strain Aspergillus niger, was examined in shake flasks. Along with the nickel recovery from COB by the fungal bioleaching, the effect of surfactant on the growth of the A. niger was also investigated. Results show that the addition of surfactant in low concentration was favorable for the recovery of nickel from pre-treated COB. Normally, the carbon source （sucrose） in the culture medium was utilized by the A. niger for its cellular metabolism and organic metabolites （bio acids） were produced, which were responsible for the bioleaching of minerals. However, the addition of surfactant （Tween-20） accelerated the rate of sucrose consumption by the fungi, and thus enhancing the extraction of nickel from pre-treated COB. During the study, around 39% nickel extraction was achieved in A. niger mediated bioleaching performed at 2% pulp density of pre-treated COB at 30 °C, in the presence of surfactant whereas only 24% nickel was extracted without surfactant.

Rule of oxygen transmission in dump leaching

According to the chemical equations, the flux and concentration of oxygen required during bacterial lea- ching sulfuric mineral were investigated; the rule of air bubble transmitted in granular was researched in the Dump Leaching Plant of Dexing Copper Mine. The results show that lack of oxygen in dump leaching is the critical factor of restricting leaching reaction. Pyrite is the primary oxygen-consuming mineral in bioleaching. When its content is too high, it needs a great deal of oxygen for reaction and competes for the finite oxygen with objective minerals, and thus the leaching velocity decreases greatly. The average size of ore particles and diameter of bubbles are the key parameters affecting the mass transfer coefficient. Reverse analysis was adopted, and it shows that 44.8 m^3 air per unit ore can meet the requirement of production if the molar ratio of pyrite to chalcopyrite is 10.

Kinetics of the leaching of TiO_2 from Ti-bearing blast furnace slag

Ti-bearing blast furnace slag is a valuable secondary resource containing about 24 percent of TiO2.In this paper a process of leaching Ti-bearing blast furnace slag with sulfuric acid to recover TiO2,and the kinetics of that reaction,are described.Under laboratory conditions the rate is controlled by a chemical reaction.The leaching reaction is in accord with a shrinking unre- acted-core model.The apparent reaction order of the leaching reaction was 1.222 and the apparent activation energy was 87.01 kJ/mol.The model fits the observed data well until 90%of the TiO2 has be leached from the particles.The model disagrees with observations during later periods of the reaction because the solution becomes supersaturated with Ti ions,which precipitate as H2TiO4.The assumptions of constant reactant concentration and that there is no effect from the product layer on diffusion,also cause the model to deviate from the actual values.

Homology modeling and docking studies of IscS from extremophile Acidithiobacillus ferrooxidans

The gene iscS-3 from ,4cidithiobacillus ferrooxidans may play a central role in the delivery of sulfur to a variety of metabolic pathways in this organism. For insight into the sulfur metabolic mechanism of the bacteria, an integral three-dimensional （3D） molecular structure of the protein encoded by this gene was built by homology modeling techniques, refined by molecular dynamics simulations, assessed by PROFILE-3D and PROSTAT programs and further used to search bind sites, carry out flexible docking with cofactor pyridoxal 5＇-phosphate（PLP） and substrate cysteine and hereby detect its key residues. Through these procedures, the detail conformations of PLP-IscS（P-I） and cysteine-PLP-IscS（C-P-I） complexes were obtained. In P-I complex, the residues of Lys208, His106, Thr78, Ser205, His207, Asp182 and Gln185 have large interaction energies and/or hydrogen bonds fixation with PLP. In C-P-I complex, the amino group in cysteine is very near His106, Lys208 and PLP, the interaction energies for cysteine with them are very high. The above results are well consistent with those experimental facts of the homologues from other sources. Interestingly, the four residues of Glul05, Glu79, Ser203 and Hisl80 in P-I docking and the residue of Lys213 in C-P-I docking also have great interaction energies, which are fitly conservation in IscSs from all kinds of sources but have not been identified before. From these results, this gene can be confirmed at 3D level to encode the iron-sulfur cluster assembly protein IscS and subsequently play a sulfur traffic role. Furthermore, the substrate cysteine can be presumed to be effectively recruited into the active site. Finally, the above detected key residues can be conjectured to be directly responsible for the bind and/or catalysis of PLP and cysteine.

Research and development trends of hydrometallurgy:An overview based on Hydrometallurgy literature from 1975 to 2019

Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the field of hydrometallurgy,we try to catch the research and development trends from a global perspective.Firstly,keywords burstness shows that rare earth,recycling,lithium,ionic liquid,and thorium are the hotspots in recent years,and the economic and technological reasons behind them were discussed in depth.Secondly,the proportion of biohydrometallurgy grows fast from 5%to 13%and the related articles are almost all about bioleaching.There are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted techniques.Thirdly,the advanced instrument analysis methods such as XAFS(X-ray absorption fine structure),gene sequencing,and micro-CT promote the deep understanding of hydrometallurgy mechanism.Finally,the cooperation network and contribution of the main institutes were mapped.

Extraction of germanium(IV) from acid leaching solution with mixtures of P204 and TBP

Solvent extraction experiments were conducted from acidic solutions containing germanium（IV） and other metal ions, such as Ga3＋, Fe3＋, Zn2＋ and Fe2＋ in hydrometallurgical process of zinc. The purpose of this work was to enhance the efficiency of the extraction and stripping processes and the selectivity of germanium and other metals, while making the method as simple as possible. Germanium was recovered from sulfuric acid, using di-（2-ethylhexyl） phosphoric acid （P2O4） as an extractant, tributyl phosphate （TBP） as modifier diluted in sulfonate kerosene and stripped by NaOH aqueous solution. Extraction studies were carried out under different acid concentrations and solvent concentrations, and optimized conditions were determined. The numbers of stages required for extraction and stripping of metal ions were determined from the McCabe-Thiele plot. The results show that the extracting and stripping efficiencies are 94.3% and 100%, respectively, through two-stage extraction and two-stage strip. Moreover, the synergistic effect of TBP on the system P2O4/kerosense/Ge4＋ is revealed with respect to the extraction of germanium.

Studies on the Allelopathic Potential of Corn （Zea mays L.） Aqueous Extracts and Root Exudates

This investigation was carried out at Faculty of Agriculture and Forestry-University of Duhok/Kurdistan-Iraq. Three experiments were included in this investigation： （1） First experiment was a bioassay related to the germination performance, shoot and root development of corn （Zea mays L.） and peanut （Arachishypogaea） at two concentrations of root （3% and 1.5%） and shoot （12% and 6%） aqueous extracts of corn medium; （2） The second experiment dedicated to the intercropping of corn and peanut at four treatments; （3） While the third experiment involved the effect of peanut root exudation on growth of corn. Experiment results revealed that corn shoot and root water extracts highly inhibited seed germination of both corn and peanut, the inhibitory of shoot extract was more than root aqueous extract. While its effect on the seedling growth was vice versa as compared with control treatment, there was an increase in root and shoot length of both corn and peanut when grown in corn aqueous extracts. Intercropping experiment results has stimulated most traits of peanut under studying. Also for corn, there was apparent and significant increase in all characteristics as compared with control. It was further confirmed from the results of peanut root exudates that had all studied characters of corn were stimulated than the control treatment.

醒酒饮料的加工技术

饮酒过量,不仅易伤身体,而且容易发生意外事故。饮用本配方制得的饮料有醒酒作用,可减少酒精对人体的危害。本剂之所以有醒酒作用,主要因为本剂中添加的喹宁和柚皮、龙胆皮浸取物,会加速血液中的酒精更快地降解。1.特点与用途(1)本剂既可作为醒酒饮料,又可作为一种保健饮料。(2)全部原料可食。

Humic-Like Substances from Different Compost Extracts Could Significantly Promote Cucumber Growth

The effects of direct extracts of compost (DEC), aerated fermentation extracts of compost (AFEC) and non-aerated fermentation extracts of compost (NAFEC) on cucumber growth and the action mechanisms were evaluated based on the structure and activity analysis of humic-like substances. AFEC increased cucumber growth most significantly, followed by DEC and NAFEC, which was insignificant compared to the control treatment. Humic-like substances from compost extracts played an important role in promoting cucumber growth. Application of humic-like substances stimulated auxin-like activity and increased chlorophyll content and nitrogen accumulation in plants. The positive auxin-like activity of humic-like substances could be attributed to the relative distribution of special carbon groups, such as those with a large amount of peptidic and carbohydratic groups or with a low content of phenolic groups. In conclusion, the best growth promotion by application of AFEC was mainly attributed to the humic-like substances in the AFEC.