矿物微观结构的多重分形

分形与多重分形已广泛地应用于不同领域,不同尺度下的各种分布特征研究更是受到广泛关注.以云南个旧松树脚矿田中2件含矿矽卡岩样品中黄铁矿颗粒为研究对象,通过分形与多重分形方法研究了黄铁矿颗粒在二维空间上的分布特征.结果显示,黄铁矿在微观尺度空间上的分布不均一,具有明显的分形与多重分形分布特征.所选研究区外接触带黑绿色含硫化物矿石矽卡岩和接触带矽卡岩型块状硫化物矿石显微照片分析结果显示,前者黄铁矿颗粒分布的盒子维数D0、信息维数D1、关联维数D2及广义多重分形维数Dq的变化范围均较小,而后者较大;前者外接触带黑绿色含硫化物矿石矽卡岩含矿性相对较弱,而后者矿石矿物相对富集.从这个意义上说,分形与多重分形维数与样品含矿性有一定的对应关系,因此,分形与多重分形分析有望进一步为岩石含矿性的定量化评价提供微观尺度上的证据.

Technological mineralogy and environmental activity of zinc leaching residue from zinc hydrometallurgical process

Chemical, physical, structural and morphological properties of zinc leaching residue were examined by the combination of various detection means such as AAS, XRF, XRD, M？ssbauer spectrometry, SEM-EDS, TG-DSC, XPS and FTIR. The toxicity characteristic leaching procedure （TCLP） was used to investigate the environmental activity of zinc leaching residue for a short contact time. The phase composition analysis indicated that the zinc leaching residue mainly consists of super refined flocculent particles including zinc ferrite, sulfate and silicate. The physical structural analysis showed that it has a thermal instability and strong water absorption properties. The results of TCLP indicated that the amounts of Zn and Cd in the leaching solution exceed 40 and 90 times of limit, respectively, which demonstrate that this residue is unstable in weak acidic environment for a short contact time.

Preparation of crystalline Mg(OH)2 nanopowder from serpentinite mineral

In this paper we describe a route to produce crystalline Mg（OH）2 nanopowders from serpentinite ore distributed in the Halilovskiy array （Russia, Orenburg region）. An efficient extraction route consisting of treatment on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for Mg（OH）2 precipitation was demonstrated. In this study, crystalline Mg（OH）2 nanopowders have been synthesized by solvothermal reaction method using （Mg（NO3）2·6H2O） which were obtained from serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-active substance. Microstructure and phase composition of samples were investigated employing scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, X-ray phase analysis （XRD）, and inductively coupled plasma optical emission spectroscopy （ICP-OES）. XRD reveals that Mg（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline Mg（OH）2 nanopowders exclusively consist of lamellar-like structures and the sizes of Mg（OH）2 are 30-265 nm length or width.

Mineralogical Features and Properties of Serpentine as Indicator of the Deep Earth Subduction Processes

The article presents the results of study of composition, structure and properties of three genetic types of serpentinite, developed by chromite-bearing ultrabasic rocks, by metamorphic zones of carbonate rocks and within the zone of weathering of ultrabasic rocks. The samples were selected from deposits, located along the Main Ural Fault-the Paleozoic subduction zone （named GUR）. Peculiarities of microstructure, chemical composition and properties of serpentinites formed in different geological conditions were investigated and their comparative study was held. They were devided three groups of serpentinites with oriented and non-oriented structure which formed by different protholites： mantle, lithosphere and crust.

Durability of Concrete Made with Manganese Slag as Supplementary Cementitious Materials

This paper discusses mineral composition and pore microstructure characteristics of water-cooled manganese slag and its effects on durability of concrete. The Mn slag has an alveolate pore structure, and the ground Mn slag is characterized by multiangular shape which consists of a＇-C2S, C3M82, CaO.MnO-2SiOu and C2AS. Experimental results show that the Mn slag has potential hydraulic reactivity. Concrete made with Mn slag as supplementary cementitious materials （SCMs） exhibits very low strength loss and weight loss in the synthetic seawater corrosion and freezing-thawing cycle tests. The research provides useful reference for knowing about Mn slag and for applying Mn slag to improve the durability of concrete.

Analysis of the strengthening and toughening of a biomaterial interface

Based on the transmission electron micrographs of nacre, the existence of mineral bridges in the organic matrix interface is confirmed. It is proposed that the microarchitecture of nacre should be considered as a “brick-bridge-mortar” (BBM) arrangement rather than traditional “brick and mortar” (BM) one. Experiments and analyses indicate that the mineral bridges effectively affect the strength and toughness of the interfaces in nacre. Comparison with a laminated composite with BM structure, SiC/BN, shows that the pattern of the crack extension and the toughening mechanism of the two materials are different. This reveals that the mineral bridges play a key role in the toughening mechanisms of nacre, which gives a conceptual guidance in material synthesis.