EFFECT OF SURFACE POTENTIAL AND DISPERSITY ON THE TOTAL INTERACTION POTENTIAL ENERGY BETWEEN MINERALS AND HYDROCARBON OIL

The effect ofψ-potentials anddispersities on the total interaction potentialenergy between natural hydrophobic minerals-molybdenite,graphite,talc and hydrocarbon oilis investigated based on the colloid and surfacescience.     

Properties of Highly-Dense Iron‐Base Powder Metallurgy Materials Pressed without Zinc Stearate

The possibility of obtaining highlydense compacts by single pressing and sintering and the use of heatresistant solid lubricants (graphite, talc) instead of conventional lubricant was studied. It was shown that the addition of graphite is most effective to obtain highly-dense powder metallurgy materials since it substantially facilitates ejection of the part from the die and improves the mechanical properties.     

滑石粉原位聚合改性聚酯热熔胶的结晶性能

采用差示扫描量热仪研究了滑石粉原位聚合对聚酯热熔胶非等温结晶性能的影响,并用Takhor方程和莫志深非等温结晶动力学新方程处理所得数据。结果表明:滑石粉原位聚合显著促进了聚酯热熔胶的结晶,提高了结晶速率,表现在结晶温度和结晶活化能大幅提高,当降温速率分别为5,10℃/min时,半结晶时间缩短50%以上。动力学分析表明:莫志深方程适合描述聚酯热熔胶的非等温结晶过程,在达到相同相对结晶度时,加入滑石粉的聚酯热熔胶所需降温速率更小,缩短了热熔胶涂覆后的冷却固化时间。     

添加剂对滑石质瓷坯料料浆性能影响研究

通过X射线衍射、流动度、厚化度分析等检测手段,研究了不同种类添加剂对滑石质瓷坯料料浆流动性、稳定性、触变性的影响。结果表明:六偏磷酸钠、硅酸钠、碳酸钠、萘磺酸甲醛缩合物、复合添加剂均可以降低滑石质瓷坯料料浆的黏度,提高料浆流动性;六偏磷酸钠与硅酸钠对料浆流动性的改善作用都优于碳酸钠;萘磺酸甲醛缩合物对滑石质瓷坯料料浆黏度降低效果比无机添加剂更加明显,其最佳添加量为0.06%,但添加之后坯料料浆的触变性严重,悬浮稳定性变差;复合添加剂最佳添加量为0.08%,复合添加剂对滑石质瓷坯料料浆性能的改善作用优于以上单一种类的添加剂。     

电子探针在中药滑石质量检验中的应用

滑石是一种十分重要的中药矿物药,其质量检验对于人体健康和环境至关重要。本文提出的以电子探针为主、并辅以X光衍射分析等方法的滑石质量检验途径,是一次新的探索。正是由于电子探针可以同时进行高倍图像观察和定性定量分析,对滑石中的杂质分析灵敏度更好,其检测结果也更直观易懂。     

Asymmetric alumina-based ultrathin composite ceramic membranes with interfacial modification of black talc nanosheets

In this work, ultrathin planar alumina-based ceramic membranes with asymmetric structure and thickness less than 0.85 mm were successfully prepared by one-step molding phase transformation/sintering method using low-cost black talc (BT) nanosheets for the first time. The microstructure, pore structure, mechanical strength and permeability of novel ceramic membranes were systematically investigated with different BT amount and sintering temperatures. The doping of BT nanosheets effectively modulated the interfacial bonding area and strength between the grains, achieving significant increase in flexural strength through the evolution of the dense layer structure. The asymmetric structural features formed by the phase transformation/sintering process in combination with polymer substrate significantly reduced the thickness of effective separation layer, thus weakening the loss of flux caused by the densification of the film layer due to the interfacial modification process. Moreover, the organic carbon layers between BT layers were oxidized during the sintering process, forming fine pores and increasing the porosity, which showed to be unique characteristic different from other clay mineral materials. The prepared composite membrane had the pure water flux up to 16335 L m⁻² h⁻¹/bar at 1350 °C sintering, which achieved stable permeation of ∼5200 L m⁻² h⁻¹/bar and high retention over 90% for O/W emulsions.     

填料对二次胶粘物沉积的影响

以丙烯酸树脂作为废纸回用过程中产生的二次胶粘物的模型物,对作为填料的滑石粉和轻质碳酸钙对二次胶粘物的吸附以及沉积性能的影响进行了研究.研究结果表明,填料级的滑石粉和轻质碳酸钙对二次胶粘物具有相近的吸附能力.在没有其他可造成二次胶粘物失稳的物质加入时,滑石粉和轻钙对二次胶粘物的吸附会导致沉积的产生;与不加入填料相比,在阳离子聚丙烯酰胺和阳离子淀粉加入量较低的情况下,填料的加入会导致沉积量的明显增加;而在阳离子聚合物加入量较大的情况下,阳离子聚合物与二次胶粘物以及填料形成的絮聚物在纤维上的有效吸附使这种影响减小.     

Improving 2‐phenylethanol and 6‐pentyl‐α‐pyrone production with fungi by microparticle‐enhanced cultivation (MPEC)

Trichoderma atroviride IMI 206040 synthesizes the coconut lactone 6‐pentyl‐α‐pyrone (6‐PAP) de novo and Aspergillus niger DSM 821 produces the rose‐like flavour compound 2‐phenylethanol (2‐PE) from the precursor l ‐phenylalanine. Here, microparticles of different chemical composition and nominal particle diameter in the range 5–250 µm were added to shake‐flask cultures of both fungi to investigate the particles' effect on product formation. Maximum 2‐PE concentration increased by a factor of 1.3 to 1430 mg/l with the addition of 2% w/v talc (40 µm diameter). Maximum 6‐PAP concentration increased by a factor of 2 to 40 mg/l with the addition of 2% w/v iron (II, III) oxide. The influence of ions leaching out of the particles was investigated by cultivating the fungi in leached particle medium. For the first time, the positive effect of the microparticle‐enhanced cultivation (MPEC) technique on the microbial production of volatile metabolites, here flavour compounds from submerged fungal cultures, is demonstrated. The effect is strain‐ and particle‐specific. Copyright © 2014 John Wiley & Sons, Ltd.     

冬瓜山铜矿深部矿石工艺矿物学研究

冬瓜山铜矿属于复杂难选矿石,具有铜磁黄铁矿、层状滑石、蛇纹石类型矿石占比高的特点,该性质对铜的选别过程具有不利影响,影响铜精矿品位和铜回收率。因此,开展该矿石的矿物学特性研究,对指导选矿生产具有重要的现实意义。研究的主要内容包括:矿石化学成分分析、矿物组成及含量、主要矿物的粒度及嵌布特征分析、不同磨矿细度下重要矿物的解离度分析,并对影响选别指标的工艺矿物学因素进行总结。工艺矿物学研究表明,冬瓜山深部矿石中铜矿物绝大部分为黄铜矿,墨铜矿占8.46%,且含有24.26%的滑石、蛇纹石易浮层状脉石矿物;黄铜矿、墨铜矿、磁黄铁矿、磁铁矿和黄铁矿的嵌布粒度不均匀,尤其是20μm以下部分占11.04%,在磨矿细度-0.074 mm粒级含量占75%时,仍有26.06%与脉石连生。以上性质都是铜选矿的重要影响因素,对指导选矿厂生产具有重要的意义。     

Adsorption and Flotation Characteristics of the Different Types of Frothers

This article investigates the adsorption of different frothers onto talc particles. The adsorption and flotation characteristisc of tallow amine acetate (TAA) + frothers (MIBC and pine oil) was studied for talc mineral. In this study, we analyzed some parameters affecting froth flotation performance and it was determined that adsorption capacity in particular, had an important role in froth flotation enrichment. The effect of pH and adsorption time on adsorption capacity was also studied. Analyses were carried out using ultraviolet spectrometry. The results showed that MIBC had the lowest frother adsorption capacity and it improved recovery during froth flotation of on the talc. It can be said that MIBC was adsorbed on the talc surface less and provided the best conditions to generate bubbles in flotation cell.