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Jinan, China

Liu Q.-M.,Anhui University of Science and Technology | Li W.-P.,China University of Mining and Technology | Li X.-Q.,China University of Mining and Technology | Hu G.,Shandong Institute
Procedia Engineering | Year: 2011

It is more complex in roof rock damage of many coal seams by overlapping mining under the coverage of magmatic rocks than that of the single coal seam. The paper simulates the deformation-failure of roof on caving of overlapping face using DEM method to obtain deformation-failure development law. The correlation of cover rock construction feature and directional distribution of bed-separated fissures in caving is researched, and the distribution features of stress on overburden rock and deformation-failure development law of many coal seams by overlapping mining under the coverage of hard rocks are summarized. Stress concentration occurs obviously in upper part of Magmatic rocks above coal7 after coal7 mining, during the course of coal8 mining. Overlapping mining leads to increasing the height of coal seam roof destruction obviously. The results are the reasons why the possibility of conducting the upper aquifers and the water-inrush accident are increased. This research result is supposed to improve the level of water hazard prevention under aquifers. At the same time, the theory of deformation and failure of overlying rock has been enriched in coal seam mining. © 2011 Published by Elsevier Ltd. Source

Mayyas A.R.,Clemson University | Omar M.,Clemson University | Pisu P.,Clemson University | Al-Ahmer A.,Clemson University | And 4 more authors.
Journal of Power Sources | Year: 2011

This manuscript discusses the development of a 3D thermal model for a power-split hybrid powertrain, including its battery modules and power electronics. The 3D model utilizes a finite differencing (FD) heat transfer algorithm, complemented with experimental boundary conditions. The experimental setup is configured to acquire the battery current, voltage, and its inner and surface temperatures in discrete and in full-field scans. The power-split hybrid configuration is tested using a standard and artificial driving cycles. A battery resistance model is then used to couple the experimental boundary conditions with the finite differencing code, which employed a cell-based internal heat generation model to describe the pack chemical reaction mechanism. This study presents a complete analysis based on battery current and voltage in relation to vehicle speed. The proposed model also predicts the powertrain spatial and temporal temperature profiles in agreement with the vehicle actual conditions as indicated by the On-Board Diagnosis (OBD) module. © 2011 Elsevier B.V. All rights reserved. Source

Zhao X.,Shandong Jiaotong University | Zhao Y.,Shandong Institute
Advanced Materials Research | Year: 2012

Social research is a collection of methods people use systematically to produce knowledge. This paper introduces two main approaches to collect and analyze data. They are quantitative approach and qualitative approach. The advantages and disadvantages of different approaches are also explained in this paper. Source

News Article
Site: http://phys.org/space-news/

The Soret Coefficient in Crude Oil experiment will measure how hydrocarbon molecules redistribute when the temperature is not uniform. Learning how complex liquids behave is of interest to the petroleum industry and academia, who can apply the data to model real-life conditions of oil reservoirs deep underground. These measurements can only be performed in weightlessness. Set for launch on China's SJ-10 satellite on 6 April local time, the experiment consists of six sturdy cylinders, each containing just one millilitre of crude oil but compressed up to 500 times normal pressure at sea level on Earth – making it one of the highest-pressure items ever launched into space. Lifting-off from China's Juiquan site in the Gobi desert, the satellite will spend almost two weeks in orbit before it returns to Earth. After landing in Si Chuan province, the team will retrieve the experiment for detailed analysis. The experiment is a partnership between ESA, China's National Space Science Centre, France's Total oil company and China's PetroChina oil company. "The experiment is designed to sharpen our understanding of deep crude oil reservoirs up to 8 km underground," explains Antonio Verga, overseeing the project for ESA. "Imagine a packet of cornflakes – over time the smaller flakes drop to the bottom under gravity. On a molecular scale this experiment is doing something similar but then looking at how temperature causes fluids to rearrange in weightlessness," says ESA's Olivier Minster. "Deep underground, crushing pressure and rising temperature as one goes down is thought to lead to a diffusion effect – petroleum compounds moving due to temperature, basically defying gravity. "Over geological timescales, heavier deposits end up rising, while lighter ones sink. "The aim is to quantify this effect in weightlessness, to make it easier to create computer models of oil reservoirs that will help guide future decisions on their exploitation." The experiment's crude oil sits in six small titanium cylinders. One end of each cylinder is warmed while the other end is cooled. Before returning to Earth, a valve is closed to prevent the liquid from remixing during reentry. Sending such a high-pressure device into space is not to be taken lightly and the cylinders were built to withstand more than double pressure than they will during normal operations – 1000 times atmospheric pressure. A specialist company, Sanchez Technology in France, worked for the prime contractor QinetiQ Space in Belgium. The electronic unit was developed and built by the Shandong Institute of Aerospace Engineering at Yantay. The experiment passed testing with the SJ-10 spacecraft at the China Academy of Space Technology in Beijing, China last year – including thermal cycling to reproduce the extreme changes in temperature the experiment will be subjected to during its orbits of Earth, as well as vibration and shock testing to simulate launch and reentry. Two weeks ago ESA and QinetiQ staff took the 8.5 kg flight unit – about the size of a desktop computer – on a four-day drive to the remote launch site in Gansu province. The experiment with its oil-filled cells is now ready for its journey to space tomorrow. Explore further: From earth to space and back again

Sun Y.-Q.,Shandong Institute | Sun Y.-Q.,Shandong Key Laboratory of Geological Processes and Resource Utilization in Metallic Minerals | Sun Y.-Q.,China University of Geosciences | Xu H.,China University of Geosciences | And 3 more authors.
Bulletin of Mineralogy Petrology and Geochemistry | Year: 2012

The wall-rock alteration sequence of the 18th orebody in the Jinchang gold deposit is feldspathization, silicification, chloritization, sericitization, calcitization and kaolinite, including propylitic, phyllic and potassic alteration zones from central to outword parts of the complex. The gold mineralization occurs mainly in the overlapped parts of argillization and phyllic alteration zones and of argillization and propylitic alteration zones. 26 species of hydrothermal alteration minerals were identified by the short-wave infrared spectroscope technique. The positive correlation of muscovite and Au contents in these minerals suggested that the gold mineralization is closely related with the sericitization. The minerals associated with the propylitic alteration zone are chlorite + epidote + illite ± halloysite i montmorillonite i quartz, the minerals in the potassic alteration zone are K-feldspar + kaolinite + halloysite ± montmorillonite ± quartz and the minerals in the phyllic alteration zone are muscovite + halloysite ± montmorillonite ± kaolinite ± quartz. Source

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