云南会泽铅锌矿田成矿物质来源：Pb、S、C、H、O、Sr同位素制约

云南会泽铅锌矿田是我国著名的超大型特富铅锌矿田之一，由相距3公里的矿山厂和麒麟厂两个独立的矿床组成，Zn＋Pb金属量超过五百万吨，矿石品位在25%至35%之间。为确定矿床成矿流体和成矿金属来源，本文系统研究了矿床的Ph、S、C、O、H和Sr同位素组成特征。矿石硫化物的铅N位素组成均一，^206Pb／^204Pb，^207Pb／^204Pb和。^206Pb／^204Pb的变化范围分别为18．251～18．530，15．663～15．855和38.487～39．433，与围岩碳酸盐岩中浸染状黄铁矿一致，与碳酸盐地层相近，在^208Pb／^204Pb-^206Pb／^204Pb图上显示明显的线性关系，表明铅N位素组成相近的碳酸盐围岩地层提供了成矿物质。矿石硫化物的δ^14S变化范围为10．9‰～17．4‰，多数集中于13‰～17‰，表明还原硫主要来自地层中海相硫酸盐的还原，还原方式为热化学还原，下伏页岩、碎屑岩和泥质岩中的有机质在硫酸盐还原过程中发挥了重要作用。三种不同产状的脉石矿物方解石的碳氧同位素组成均一且没有明显差别，δ^13C变化范围为-2．1‰～-3．5‰, δ^18O为16.8‰～18．6‰。脉石矿物方解石中流体包裹体水的δDFI为-50‰～-60‰，取温度为200℃计算包裹体水的δ^18OH2O值为7．0‰～8.8‰。碳、氧和氢、氧同位素研究结果表明，成矿流体为来自下部上升的变质流体，由于下伏页岩、碎屑岩和泥质岩中有机质的参与，成矿流体具有低的δ^13C和δ^13DFI值，在上升过程中与围岩发生了同位素交换。矿石中黄铁矿、闪锌矿和方解石的初始锶同位素组成（^87Sr／^86Sr）．值的变化范围为0．714～0．717，赋矿围岩中未蚀变白云岩的初始锶同位素组成（^87Sr／^86Sr）．值为0.7083～0．7093，明显低于蚀变白云岩（0．7106），表明成矿流体具有高的（^87Sr／^86Sr），比值。相对围岩碳酸盐岩而言，下伏地层中的页岩、碎屑岩和泥质岩往往具有高得多的^87Sr／^86Sr，因此，流经或者起源于这些地层的流体具有高的锶同位素比值.

分散元素的超常富集与共生

本文以地质事实为基础，初步探讨了分散元素的超常富集和共生问题。在一定地质条件下，分散元素可以发生超常富集，乃至形成分散元素的独立矿床。低温条件有利于分散元素的超常富集和形成独立矿物；热水沉积作用在某些分散元素的成矿过程中具有重要意义。分散元素共生，是一种常见的现象。相似的地球化学 性质和地球化学行为，是导致分散元素共生的基本原因。男外，区域地质背景也是一个重要因素。

Enhancement of molar heat capacity of nanostructured Al2O3

The nanosized alumina prepared by the hydrolysis method with an average particle size of 20 nm was characterized by X-ray diffraction. The heat capacity measurements of the prepared sample were carried out using an adiabatic calorimeter in the temperature range from 78 to 370 K. Enhancement of heat capacity was observed in the nanostructured materials as the heat capacity data were compared with those of the corresponding coarse-grained materials. The enhanced heat capacity was discussed on the basis of experiments. Differential scanning calorimetry and thermogravimetry were used to determine the thermal stability of the nanostructured alumina.

Characterization of iron atoms in the framework of MFI-type zeolites by UV resonance Raman spectroscopy

Silicalite-I, ZSM-5, and Fe-ZSM-5 zeolites prepared from two different silicon sources are characterized by UV resonance Raman (UVRR) spectroscopy, X-ray diffraction (XRD), electron spin resonance (ESR), and UV/visible diffuse reflectance spectroscopy (UV/Vis DRS). A new technique for investigating zeolitic structure, UV resonance Raman spectroscopy selectively enhances the Raman bands associated with framework iron atoms incorporated into MFI-type zeolites, and it is very sensitive in identifying the iron atoms in the framework of zeolites, while other techniques such as XRD, ESR, and UV/Vis DRS have failed in uncovering trace amounts of iron atoms in the framework of zeolites. (C) 2000 Academic Press.

Imaging of three-dimensional objects in emission electron microscopy

Under investigation by emission electron microscopy, the shape and size of three-dimensional objects are distorted because of the appearance of a characteristic potential relief and a possible contact potential difference between the particles and the substrate. An estimation of these effects for spherical particles is made. It is shown that the apparent size of particles observed in an emission electron microscope (EEM) could be increased as well as decreased depending on the relation between the work functions of the particle and the substrate. The corresponding formulae are given and several possibilities are shown which permit us to determine from the EEM image the real size of particles and their work function relative to the substrate.

Selecting Informative Features with Fuzzy-Rough Sets and its Application for Complex Systems Monitoring.

Q. Shen and R. Jensen, 'Selecting Informative Features with Fuzzy-Rough Sets and its Application for Complex Systems Monitoring,' Pattern Recognition, vol. 37, no. 7, pp. 1351-1363, 2004.

Steady-state motion of a Mode-III crack on imperfect interfaces

Mishuris, Gennady; Movchan, N.V.; Movchan, A.B., (2006) 'Steady-state motion of a Mode-III crack on imperfect interfaces', Quarterly Journal of Mechanics and Applied Mathematics 59(4) pp.487-516 RAE2008

Informe final de viaje: asesoría en diseño.

16 hojas : ilustraciones, cuadros.

Transformaciones básicas de las funciones

En el desarrollo de esta actividad se discute cómo se transforma una función, de la cual se conoce su representación gráfica y no su representación algebraica. La actividad consiste en un estudio de la gráfica de una función prototipo totalmente descontextualizada. Se propone la composición de funciones, operaciones entre gráficas y su relación con algunas formas analíticas asociadas al variar algunos de sus parámetros, para mirar el comportamiento global tanto de la función compuesta, como de la familia de funciones resultantes; que permita relacionar la representación gráfica de una función compuesta con las funciones que la componen y explorar patrones en las familias de éstas y así poder predecir el comportamiento de una función cualquiera bajo este tipo de transformaciones.

Turbulence modelling and its impact on CFD predictions for cooling of electronic components

This paper will discuss Computational Fluid Dynamics (CFD) results from an investigation into the accuracy of several turbulence models to predict air cooling for electronic packages and systems. Also new transitional turbulence models will be proposed with emphasis on hybrid techniques that use the k-ε model at an appropriate distance away from the wall and suitable models, with wall functions, near wall regions. A major proportion of heat emitted from electronic packages can be extracted by air cooling. This flow of air throughout an electronic system and the heat extracted is highly dependent on the nature of turbulence present in the flow. The use of CFD for such investigations is fast becoming a powerful and almost essential tool for the design, development and optimization of engineering applications. However turbulence models remain a key issue when tackling such flow phenomena. The reliability of CFD analysis depends heavily on the turbulence model employed together with the wall functions implemented. In order to resolve the abrupt fluctuations experienced by the turbulent energy and other parameters located at near wall regions and shear layers a particularly fine computational mesh is necessary which inevitably increases the computer storage and run-time requirements. The PHYSICA Finite Volume code was used for this investigation. With the exception of the k-ε and k-ω models which are available as standard within PHYSICA, all other turbulence models mentioned were implemented via the source code by the authors. The LVEL, LVEL CAP, Wolfshtein, k-ε, k-ω, SST and kε/kl models are described and compared with experimental data.

Effect of particle concentration on erosion rate of mild steel bends in a pneumatic conveyor

Particle concentration is known as a main factor that affects erosion rate of pipe bends in pneumatic conveyors. With consideration of different bend radii, the effect of particle concentration on weight loss of mild steel bends has been investigated in an industrial scale test rig. Experimental results show that there was a significant reduction of the specific erosion rate for high particle concentrations. This reduction was considered to be as a result of the shielding effect during the particle impacts. An empirical model is given. Also a theoretical study of scaling on the shielding effect, and comparisons with some existing models, are presented. It is found that the reduction in specific erosion rate (relative to particle concentration) has a stronger relationship in conveying pipelines than has been found in the erosion tester.