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September 30,2012
Volume 5,Issue 18
Pages -
Subject Area:Geodesy,Geographic Information System,Bioenergy

Title: Spatial and temporal variation of Lianyungang coastlines based on satellite remote sensing during past 30 years

Authors: WANG Hongmei, CAI Yulin, GAO Xiangwei
PP: 1780-1785
Abstract: In this paper, four remote sensing images acquired during the period of 1979-2009 were used to extract information about Lianyungang coastlines. Spatial and temporal variation of Lianyungang coastline was revealed and then driving mechanism was analyzed from human and nature viewpoints. The results showed that in the coast where human activities are frequent, coastline is pushed to the ocean while in the coast where there are less human activities, coastline is back to the land.
Keywords: photogrammetry and remote sensing technology; Lianyungang; coastline; spatial and temporal variation

Title: An alternative method of measuring observation pier

Authors: YANG Hao
PP: 1774-1779
Abstract: Trigonometric leveling principle was applied to develop a virtual observation pier technology, which was used to replace periodic subsidence monitoring for the deformation body on the actual fixed observation pier. The purpose was to achieve precise subsidence monitoring with high accurate instrument high when a fixed observation pier can’t be set up on the reference point due to the engineering environmental conditions, or a fixed observation pier is not required. The initial observation value of virtual observation pier backsight point was firstly obtained before the formal monitoring beginning. When formal monitoring was carried out, the total station was set up on the reference point then the backsight point was observed. The height of total station was obtained accurately using the mathematic method, on the basis of the observed value. The results showed that the effectiveness of subsidence monitoring was equal to that of actual fixed observation pier.
Keywords: engineering survey technology; virtual observation pier; observation pier; total station; equipment height; trigonometric leveling

Title: Study on RAIM algorithms of GPS/GLONASS combination system

Authors: JIANG Kun, WANG Jian
PP: 1769-1773
Abstract: As the phase of multi-system co-existence and multi-technology integration in the global positioning system can provide a large amount of visible satellites to users, how to ensure the completeness of the satellite constellation, and to achieve higher positioning accuracy and reliability has become a research topic of concern. Receiver autonomous integrity monitoring (RAIM) techniques take the fault detection and exclusion techniques as the core, optimize global navigation satellite system (GNSS) satellite constellation and ensure the navigation solution meet the requirements of the practical application. This paper established GPS/GLONASS combination system simulated constellation, verified the feasibility of RAIM algorithm by simulation data, and pointed out the key factors of different combination of constellation.
Keywords: geodesy and survey engineering; GPS/GLONASS combination system; receiver autonomous integrity monitoring; fault detection and exclusion

Title: Studies on land use change based on RS and GIS

Authors: LIU Jin, LI Gang
PP: 1763-1768
Abstract: Taking the thematic mapper (TM) image of 2000, 2004 and 2006 and the thematic map, statistic data of Peixian county as data source, the land use change characteristics in the past 6 years were studied based on remote sensing (RS) and geographic information system (GIS) technology, with the support of ENVI, ArcGIS and other software. The results showed that during the period of 2000 to 2006, the change of land use types in Peixian county had been in large amplitude, with the large reduce of arable land, the habitation, industrial and mining land had been increasing massively in the meantime; while on the contrary of the forestland’s slightly increased, water land and the unutilized land had decreased gradually. The main driving forces for this land use change were the increased population, the economic development, the policy changes, the promoting role of urbanization and so on.
Keywords: geographic information system; remote sensing; land use change; transfer matrix; driving forces

Title: Remote sensing research on relationship between urban building materials and land surface temperature

Authors: LIU Wenyu, GONG Adu, XIANG Jianjing, NIU Yanbo
PP: 1754-1762
Abstract: PROBA compact high resolution imaging spectrometer (CHRIS) hyperspectral image is used to extract building materials and natural surfaces based on a hierarchical classification method in Beijing. In this study, the relationships between building materials in the urban area and land surface temperature are quantitatively analyzed by combining with land surface temperature in Beijing retrieved by thermal infrared data of Landsat 5 thematic mapper (TM), and the influence on urban heat island (UHI) leaded by different materials and the influencing factors are discussed. The results indicate that the brick and tile-roof buildings have the highest temperature, and are about 1.6~3.6 K higher than the other building materials, 6.0~8.3 K higher than natural surfaces; metal surface, concrete, cement and asphalt have nearly the similar surface average temperature and lower than brick and tile; the glass curtain wall can reduce the surface temperature effectively and is about 2.4~3.2 K lower than the others.
Keywords: geographic information system; remote sensing; urban heat island; building materials; land surface temperature; compact high resolution imaging spectrometer data; TM data

Title: Research on Q-switch Nd: YVO4 laser to open tiny holes on the silicon

Authors: ZHANG Weiguo, LIANG Zongcun, SHEN Hui, ZHUANG Shuqin, LIN Hande
PP: 1745-1753
Abstract: To solve the heavy taper problem in the preparation of making the special structure of crystalline silicon solar cells, Q-switch Nd:YVO4 laser was used to open tiny holes on silicon wafer. According to the characteristics of laser, the complexity of interaction of the laser beam with the silicon wafer, it was found that the relationship between parameters of holes-opening process and the holes-diameter, depth, and ratio of upper and bottom diameter was not a simple linear. Furthermore, the research provided a set of feasible and low-cost scheme to reduce the taper of the round table when opening holes by laser. Finally, a 7∶6 ratio of upper and bottom diameter in a 0.22 mm thick silicon wafer was obtained successfully, which could meet the following step process of some special structure crystalline silicon solar cells such as the emitter wrap through (EWT) type well.
Keywords: solar energy; emitter wrap through solar cell; laser opening tiny holes; crystalline silicon; ratio of upper and bottom diameter; taper

Title: Impact of different sodium incorporation methods on electrical, structural and micrograph properties of Cu(In,Ga)Se2 thin film

Authors: HE Jingjing, LIU Wei, LI Zhiguo, SUN Yun
PP: 1741-1744
Abstract: Incorporation of sodium into Cu(In,Ga)Se2 (CIGS) thin films deposited on flexible substrate leads to a great improvement in the properties of CIGS. Different influences were found by using different sodium incorporation methods. In this work, CIGS was deposited on flexible polyimide (PI) substrate by three-stage process based on low-temperature deposition. The research focuses on the impact of two different sodium incorporation methods, deposition of a sodium compound precursor and post-deposition treatment of a sodium compound, on electrical, structural and micrograph properties of CIGS thin film. X-Ray diffraction (XRD) measurement shows that the interdiffusion of In-Ga is restrained, which exhibits a double-peak reflection pattern when sodium is available during the growth of CIGS. In addition, the growth of CIGS is affected due to sodium incorporation, which leads to a decreased grain size observed by means of scanning electron microscopy (SEM).
Keywords: solar energy; CuInxGa(1-x)Se2; flexible substrate; low-temperature deposition; sodium incorporation

Title: Influences of washing and K2CO3 on pyrolysis behavior of palm oil wastes

Authors: DU Shenglei, YANG Haiping, CHEN Hanping, WANG Xianhua, ZHANG Shihong
PP: 1734-1740
Abstract: The impact of washing and K2CO3 on pyrolysis behavior of palm oil wastes was studied in this paper. Thermogravimetric analyzer (TGA) and Fourier transform infrared spectroscopy (FTIR) was applied to explore the pyrolysis mechanism of pretreated palm oil wastes samples and the subsequent releasing gas products. Kinetic parameters of the samples were calculated using Coats-Redfern method. The results showed the pretreatment had significant influences on the samples’ pyrolysis characteristic and the components of gas products: washing led to the increasing of initial pyrolysis temperature; K2CO3 addition led to the decreasing of the initial pyrolysis temperature and pyrolysis activation energy; weight loss rate shifted from a bimodal structure to a single peak. The addition of K2CO3 promoted the volatilization of the small molecule gas such as CO and CO2 under low temperature and enhanced their total yield obviously while reduced the amount of hydrocarbon and CH4 by a large margin.
Keywords: biomass; water leached; K2CO3; pyrolysis; catalysis

Title: Formation of catalyst layers of membrane electrode assembly using electrohydrodynamic

Authors: WANG Dazhi, LI Yang, WANG Liang, LIANG Junsheng, LIU Chong
PP: 1728-1733
Abstract: In this paper, Pt/C and Pt-Ru/C nano-suspension are used to prepare the membrane electrode assembly (MEA) for direct methanol fuel cells (DMFC) using electrohydrodynamic atomization (EHDA) layer-by-layer deposition method. During the EHDA deposition process, the Pt/C and Pt-Ru/C nano-suspensions produce stable cone-jet mode and the atomization characteristics are studied. Pt/C and Pt-Ru/C nano-suspension are deposited on the carbon paper to form cathode and anode catalyst layers under this stable cone-jet mode. The cathode and anode catalyst layers present porous and well-packed features. The average pore size of the cathode and anode catalyst layers is 3.5 μm and 4.0 μm, respectively. The polarization behaviour of a single DMFC assembled with the deposited MEA at different working temperatures are analysed. The results show that the cell performance increases fast when temperature increases from 20℃ to 60℃, however, the cell performance has inconspicuous difference when temperature higher than 60℃.
Keywords: energy science technology and other subjects; catalyst layer; electrohydrodynamic atomization; direct methanol fuel cells; membrane electrode assembly

Title: Effect of rainfall on seepage field and stability of tailings dam

Authors: YIN Guangzhi, WANG Wensong, ZHANG Qiangui, GENG Weile, LI Minghui
PP: 1720-1727
Abstract: The present paper focuses on the study of a case, a tailing dam from the iron industry located in Sichuan province, with the objective of gaining knowledge about the influence of rainfall infiltration on seepage field and stability of tailings dam. Based on the unsaturated soil mechanics theory, numerical simulation analysis of seepage field and calculation of stability with different rainfall intensities were performed by applying Slide program. The research results showed that the seepage line rises with the increase of rainfall intensity, while the effect of matric suction decreases and stability of dam reduces. The safety factor of tailings dam is lower than the value of national specification when the rainfall intensity reaches to the maximum in history. Therefore, drainage facilities should be built to enhance drainage capacity of dam. The research results can provide guidance for design and construction of tailings dam and afford positive and instructive references for other tailings dams.
Keywords: mine safety; mining engineering; tailings dam; numerical simulation; rainfall; stability

Title: Static simulation analysis of lower crossbeam of the large-scale linear vibration screen

Authors: MA Xiaonan, WANG Xinwen
PP: 1715-1719
Abstract: This paper takes the lower crossbeam of one kind of the large-scale linear vibration screen for study, establishes its three-dimensional model with Solidworks software, and takes static simulation analysis with Solidworks-Simulation software, analyzes calculation results and contrasts stress of each weighted surface of the lower crossbeam and its distribution. The analyzed results indicates that stress of middle, 1/3 and 1/6 positions on the upper surface of channel of the lower crossbeam is the largest, where stress concentration exists and crack appears easily firstly, and provides several advices for improvement of the lower crossbeam according to analyzed results.
Keywords: benefication machinery; vibration screen; lower crossbeam; finite element; simulation analysis

Title: Experimental analysis on effects of different expansive agents on expansive deformation properties of shotcrete

Authors: MA Qinyong, LI Fuhu, HUANG Wei, CUI Pengbo
PP: 1709-1714
Abstract: To study the effects of two kinds of expensive agents (HCSA and CSA) on deformation properties of shotcrete and their microstructure, restrictive expansion ratio and microstructure of shotcrete were characterized by using expansive-shrinkage instrument, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that, shrinkage of shotcrete during hydration could be compensated by adding HCSA and CSA expansive agents efficiently. After adding 8% HCSA and CSA expansive agents, restrictive expansion ratio of shotcrete sample were 0.025% and 0.011% on the 28th day of hydration, respectively, which were much higher than that of plain shotcrete (-0.013%). HCSA and CSA expansive agents promoted the growth of ettringite crystals in micro-pores and cracks of shotcrete during hydration, which could reduce shrinkage of shotcrete. Expansive performance of HCSA is better than that of CSA expansive agent.
Keywords: mine supporting engineering; shotcrete; expansive agent; accelerating agent; experiment; expansive deformation; microstructure

Title: Research on deep cleaning technology of high ash coal

Authors: ZHANG Man, YANG Qiaowen, CHANG Huifen, REN Lv, HUANG Jing, LI Yunheng
PP: 1704-1708
Abstract: The paper uses a new type mulsion reagent composed of diesel, surfactant and water mixed on a certain proportion to perform a flotation test on coal of Taiyuan in Shanxi. The aneurpose of this paper is to reduce the dosage of collector by improving the dosage of foaming agent, and thus to reduce oil consumption and increase the economic benefits. The paper focuses on the tests of the influence of the collector dosage and foaming agent dosage on the flotation indexes to determine the relationship between them. The results showed that when the oil consumption was 4.06 kg/t and the dosage of foaming agent was 0.55 kg/t, a good effect was achieved, and the ash content of Taiyuan high ash coal was decreased from 38.68% to 17.43%, so the purpose of reducing the ash content of coalis achieved.
Keywords: mineral processing technology; flotation; mulsion reagent; deash

Title: The new direction to tourmaline research

Authors: REN Fei
PP: 1696-1703
Abstract: Tourmaline is a boron-containing ring structure of silicate minerals, belongs to the three parties of crystal, the space group is R3m. Because of its properties of the piezoelectric, thermoelectric and adsorption, tourmaline has a wide range of application values in the electromagnetic, catalysis, infrared radiation, health care, environmental protection, etc. In recent years, tourmaline has gained attention as an important functional mineral material. This paper reviewed the latest research progress of tourmaline in the structure, performance, powder preparation, adsorption, surface modification, anion, composite materials and so on during 2010-2011, suggested the key of the development and utilization for the efficient and green for tourmaline is to strengthen the application of basic research.
Keywords: mineral processing engineering; tourmaline; reviews; structure; performance; surface modification; composite

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