Physical Sciences and Mathematics Commons^™

Role Of Technological Revolution In Transport And Communications Development, Mohamad B. Chami

BAU Journal - Science and Technology

The arousal of technology has changed a lot of aspects in human life and has drastically changed its path through a revolution that changed the whole world. This revolution took place in various aspects while affecting significantly the global economy and from those fields that considerably affect the life of human beings in the previous and current centuries are Information and Communication Technology (ICT) and transportation. It is these two factors that play a major role in the economy of countries and dominate the lives of societies in the world. Thus, this paper studies the impact of the technology revolution …

Scale Model Equations And Optimization For Annular Flow Of Non-Newtonian Fluids Between Eccentric And Rotating Cylinders, Wei Zhang, Pooya Khodaparast, Amin Mehrabian Dr., Amir Shojaei

Progress in Scale Modeling, an International Journal

A broad range of engineering applications involves helical flow of non-Newtonian fluids between two eccentric cylinders. These applications often require estimation of the frictional pressure losses along the axes of the cylinders. Laboratory flow loops are commonly used to study the flow characteristics at smaller scales of investigation. This study uses the laws of similarity and dimensional analysis to obtain a set of scaling equations between the laboratory and prototype scales of the described annular flow. These equations are derived for four types of fluid rheology including Newtonian, power-law, Bingham-plastic, and yield power-law.

Results are expressed through a set of …

Photoelectrochemical Sensing Based On Zr-Mofs For Homocysteine Detection, Wen-Xia Dong, Guang-Ming Wen, Bin Liu, Zhong-Ping Li

Journal of Electrochemistry

Due to the independent form of the light source and detection system, photoelectrochemical (PEC) sensor has the advantages of low background, high sensitivity and simple operation. So far, PEC systems have been widely used in the fields including the actual detection of metal ions, biological antibodies or antigens in environmental pollutants. When the photosensitive material is irradiated by a light source with an energy being equal to or greater than its band gap, electrons (e-) transition occurs from the valence band to the conduction band, leaving a hole (h+), at the same time, the generated electron-hole pair (e-/h+) separate, and …

Effect Of Aluminum Alloy Surface Modification On Adhesion Of The Modified Polyurethane Coating And Its Corrosion Protective Performance, Xian-Yin Kuang, Shao-Qiang Jin, Yan-Hui Cao, Yan-Mei Zhang, Shi-Gang Dong, Long-Hui Zhu, Li-Wen Lin, Chang-Jian Lin

Journal of Electrochemistry

The ordinary organic coatings on aluminum alloy usually encounter a problem of low adhesion to the substrate, which results in destruction and failure of the long-term protective performance of the anticorrosion systems. The surface modification of aluminum alloy is able to enhance the adhesion of organic coating on aluminum alloys, and to improve their protective performance. In this work, a combined surface modification of anodic oxidation and mussel adhesion protein/CeO₂/3-aminopropyltriethoxysilane composite film (MCA) was developed on the aluminum alloy. The adhesion of modified polyurethane coated on the treated aluminum alloy and its corrosion protective performance were evaluated comprehensively …

Functional Sulfate Electrolytes Enable The Enhanced Cycling Stability Of Nati2(Po4)3/C Anode Material For Aqueous Sodium-Ion Batteries, Shu-Jin Li, Zhi-Kang Cao, Wen-Kai Wang, Xiao-Han Zhang, Xing-De Xiang

Journal of Electrochemistry

Aqueous sodium-ion batteries show promising application in fields of large-scale storage of intermittent renewable energies owing to the earth-abundant sodium resources and incombustible aqueous electrolytes. Primary factors determining whether they can be commercially utilized are low cost and long lifetime. Among current electrode materials, NASICON-type NaTi₂(PO₄)₃ arouses wide interests as an anode material for aqueous sodium-ion batteries as it offers a high specific capacity, fast Na-transport ability and reasonable working potential, however, suffering from insufficient cycling performance caused by severe dissolution of active materials in traditional aqueous electrolytes. In this work, a functional sulfate electrolyte …

Effect Of Glycol Based Coolant Pollution On Pem Fuel Cells Stack And Recovery Measures, Cong-Yi Zhu, Xiao-Hui Li, Quan-Quan Gan

Journal of Electrochemistry

As the heat conduction medium of fuel cell cooling system, coolant is very important for the thermal management of fuel cell stack. In practical application, coolant leakage into the stack often occurs. Due to the randomness of fault location of components, the location of coolant leakage is uncertain, which may occur on the cathode side or anode side of some or all single cells. The main effects of coolant pollution on fuel cell stack are as follows: the output of open circuit voltage decreases sharply, the consistency of single cells voltage decreases and so on, which seriously affects the normal …

Copper Nanoparticles In-Situ Anchored On Nitrogen-Doped Carbon For High-Efficiency Oxygen Reduction Reaction Electrocatalyst, Hui-Fang Yuan, Yue Zhang, Xing-Wu Zhai, Li-Bing Hu, Gui-Xian Ge, Gang Wang, Feng Yu, Bin Dai

Journal of Electrochemistry

Compared with noble metal platinum (Pt)-based catalysts, inexpensive non-noble metal electrocatalysts have attracted extensive attention for oxygen reduction reaction (ORR). Herein, chitosan as a kind of biomass resource rich in nitrogen and carbon was used to prepare nitrogen-doped carbon (N-C) and N-C in-situ anchored by copper nanoparticles (Cu/N-C). The as-obtained N-C and Cu/N-C nanoparticles were successfully used as non-noble eletrocatalysts tested for ORR. Compared with the N-C, the Cu/N-C showed the high surface area of 607.3 m 2·g-1 with the mean pore size of 2.5 nm and the pore volume of 0.40 cm3·g-1. The most positive Gibbs free …

Cyclic Voltammetric Simulations On Batteries With Porous Electrodes, Xue-Fan Cai, Sheng Sun

Journal of Electrochemistry

Lithium-ion batteries (LIBs) are among the most widely used energy storage devices. Whole-cell modeling and simulations of LIBs can optimize the design of batteries with lower costs and higher speeds. The Pseudo-Two-Dimensional (P2D) electrochemical model is among the most famous whole-cell models and widely applied in LIB simulations. P2D model consists of a series of kinetic equations to model Li+/Li diffusion in working/counter electrodes and electrolytes, which are filled in the porous electrodes and separator, and reactions at the interface of electrolyte and active particles. The traditional applications of P2D model, however, are limited to the cases where the current …

Formation And Morphological Evolution Of Nanoporous Anodized Iron Oxide Films, Jin-Wei Cao, Nan Gao, Zhao-Qing Gao, Chen Wang, Sheng-Yan Shang, Yun-Peng Wang, Hai-Tao Ma

Journal of Electrochemistry

The preparation of iron oxide films with nanoporous structure by anodization has attracted much attention for its potential applications. However, the formation mechanism of porous structure during anodization is still unclear. In this paper, the composition of anodic current during the formation of nanoporous anodized iron oxide film was analyzed in combination with the current density-potential response (I-V curve) and the derivation of Faraday’s law. The results showed that the anodic current consisted of an ionic current (leading to the migration of ions to form oxide) and an electronic current (leading to the oxygen evolution), and the …

Influence Of Heat Treatment Time On Cathode Material Cr8O21 For Lithium Battery, Jiu-Kang Teng, Qing-Jie Wang, Liang Zhang, Hong-Mei Zhang, Xiao-Tao Chen, Peng Zhang, Jin-Bao Zhao

Journal of Electrochemistry

Chromium oxide (Cr₈O₂₁) cathode material for lithium batteries was synthesized by thermal decomposition of chromium trioxide (CrO₃) at high temperature. The electrochemical properties of chromium oxide depended on the time and temperature during the heat treatment. Pure phase chromium oxide was prepared, and the effects of heat treatment time on the structures and electrochemical properties of Cr₈O₂₁ were systematically studied. The first discharge mechanism of chromium oxide in lithium batteries was explored, and the results were similar to that in lithium-sulfur batteries. The crystal phases and electrochemical properties of the prepared …

Structure Analysis Of Pemfc Cathode Catalyst Layer, Rui-Qing Wang, Sheng Sui

Journal of Electrochemistry

The sluggish oxygen reduction reaction (ORR) on the cathode of the proton exchange membrane fuel cell (PEMFC) has always been one of the key factors limiting its commercialization. The optimization of the cathode catalytic layer structure plays an important role in improving fuel cell performance and reducing production costs. In this paper, two different catalysts (platinum nanoparticles (Pt-NPs) and platinum nanowires (Pt-NWs)) were prepared by using catalyst coated substrate (CCS) method. By constructing a double-layer catalytic layer structure, we analyzed the effect of different catalytic layer structures by performing a single cell test. The results showed that the dense platinum …

Nitrogen-Sulfur Co-Doped Porous Carbon Preparation And Its Application In Lithium-Sulfur Batteries, Zhao Gui-Xiang, Hafiz Zaki Ahmed Wail, Zhu Fu-Liang

Journal of Electrochemistry

In recent years, lithium-sulfur (Li-S) batteries have been considered as a promising candidate for the next generation of energy storage system due to their ultrahigh theoretical capacity (1675 mAh·g-1) and energy density (2600 Wh·kg-1). However, the practical application of Li-S batteries is seriously limited by their insulating nature of sulfur, the shuttle effect of polysulfides (LiPSs), and volume expansion during charging and discharging. To overcome those disadvantages, one of the commonly methods is to infiltrate sulfur into porous conductive carbon framework, such as porous carbon, hollow carbon spheres, graphene, carbon nanotubes and some composites of the above structures to achieve …

Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, Long Linli, Liu Ying, Zhang Xuyang, Su Yongdong, Chen Xiaoyang

Coal Geology & Exploration

With the emergence and development of UAVs and the improvement of the miniaturization and intelligence of various sensor, UAVs equipped with sensors have become an efficient tool for obtaining spatial data. Because UAVs are low cost, short revisit period, fast and efficient, light and flexible, simple operation, and high temporal and spatial accuracy of image acquisition, it is widely used in mining land damage monitoring. Using "UAV, Inversion, Soil Monitoring, Surface Collapse, Ground Fissure" as keywords, this paper summarizes the academic papers of the search system in the web of science, CNKI, and Google Scholar from January 2010 to May …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Analysis Of Organic Matter Maturity Of Sapropel Coal In Oil Layer A Of Haishiwan Mine Field Of Yaojie Mining Area, Song Xiaozhong, Zhang Bingzhong, Lei Ying, Song Yanqiang

Coal Geology & Exploration

The vitrinite reflectance is recognized as the only comparable evaluation index of organic matter maturity of source rock in the exploration and development of oil and gas, shale gas and coalbed methane resources. Current research was done to determine the organic matter maturity of sapropel coal in oil layer A in Haishiwan mine field more accurately. Coal samples were collected from boreholes and observation of the optical characteristics of reflected light and fluorescence microscopic components were studied under the microscope. It was found that there are two different characteristic vitrinites in sapropel coal in oil layer A. One was fluorescent …

A 3d Seismic Physical Modeling System Of Large Double Triaxial Air-Supported Positioning And Multichannel Data Acquisition And Its Application, Shi Xianxin, Liu Qiang, Hu Jiwu, Wang Pan, Lian Chenguang, Jia Qian, Zhang Miaomiao, Nie Ailan

Coal Geology & Exploration

As an important technology to study seismic wave propagation characteristics, 3D seismic physical simulation is an effective method to understand the propagation law and response characteristics of seismic waves in complex structures. It has the advantages of more realistic results and no limitation on calculation methods and boundary conditions over numerical simulation. Therefore, it has important applications in the research of the basic law of seismic wave propagation, verification of field seismic exploration methods, design optimization of observation systems, etc. This paper presents a 3D seismic physical modeling system of large double triaxial air-supported positioning and multichannel data acquisition, which …

Deformation Characteristics Of Coal Measures And Gas Occurrence Law Of Coal Mines In North China, Wang Wei, Wei Yanzhao, Jia Tianrang, Yan Jiangwei

Coal Geology & Exploration

Gas is not only one of the important disaster-causing factors in coal mines, but also an important clean energy. Understanding the deformation characteristics of coal measures and the occurrence of gas is the basis for coal mine gas disaster prevention and coalbed methane development. Taking the North China coal measures as the research object, taking the tectonic evolution and control as the main line, using the theory of plate tectonics, tectonic evolution and step by step control of gas-occurring structures, the deformation characteristics of the North China coal-measures and the law of coal mine gas occurrence were systematically studied. The …

Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang

Coal Geology & Exploration

Coal and gas outburst induced by mining disturbance is one of the main gas dynamic disasters in coal mine production. In order to systematically explore the evolution characteristics of coal damage and the law of gas seepage under mining disturbance, the whole stress strain–seepage experiment under different gas pressures was carried out. The generalized Hooke's law was modified by considering the effects of gas adsorption and thermal expansion, the plastic deformation-based constitutive relation of coal damage was established, and the piecewise permeability model considering the damage was further constructed. The results shown that the coal permeability can be divided into …

Saxs-Based Nano-Scale Pore Structure Characteristics Of Coals With Different Metamorphic Degrees, Zhang Yu, Li Yong, Wang Yanbin, Wang Zhuangsen, Zhao Shihu, Han Wenlong

Coal Geology & Exploration

In order to reveal the characteristics of nano-scale pores in coals with different metamorphic degrees, the small-angle X-ray scattering method (SAXS) is used to obtain the porosity, pore size distribution, specific surface area and fractal dimension of 15 samples whose vitrinite reflectance R_max is 0.31%-6.24%, and the low temperature CO₂ and N₂ adsorption DFT model results are used to verify the pore size distribution. The results show: during coalification process, when R_max is < 0.5%, the porosity and the specific surface area of coal increase with the increase of metamorphic degree, the micropores(< 2 nm) content increases seldomly, the mesoporous(2-50 nm) and microporous(50-100 nm) content increase greatly, and the surface of coal is gradually smooth. When R_max=0.5%-1.4%, the porosity and the specific surface area decrease, and each type of pore content is reduced, and the surface of …

Discussion On The Water-Preserved Coal Mining By Dewatering-Reflooding Water Curtain In Open-Pit Coal Mines, Li Ying, Yang Zhuo, Wu Tong

Coal Geology & Exploration

To suppress the attenuation of groundwater resources caused by drainage and control the influence range of coal mining on groundwater resources, the coal mining technology with water curtain was adopted. Taking an open-pit coal mine as the background, this paper established a sand trough recharge platform to carry out physical experiments, and used a numerical method to simulate the irrigation area, so as to analyze the formation and variation of the dewatering-reflooding water curtain. Physical experiments were carried out to observe the formation of a fixed head boundary by water injection curtain which prevented the expansion of funnel, the influence …

The Development Law Of Surface Cracks In Shallow Coal Seam Mining Through Double Gullies Terrain, Sun Xueyang, Zhang Huixuan, Lu Mingjiao, Li Cheng, Miao Lintian

Coal Geology & Exploration

In order to protect the ecological environment of the mining area in the Yellow River Basin, the mining-induced surface crack development law was summarized from the parameters of surface crack development location and development morphology during mining of the working face passing through the double gullies terrain by using a combination of numerical simulation experiments, similar material simulation experiments and theoretical analysis in the context of the working face 125203 of Anshan Coal Mine in Miaohagu Mining Area of Fugu County. Through theoretical analysis, the relative position function T of surface cracks in shallow coal seam mining through double gullies …

Numerical Analysis Of The Effect Of Different Soil Types And Water Content On Heat Transfer Performance Of Horizontal Buried Pipes, Zou Hang, Pei Peng, Hao Dingyi, Wang Chen

Coal Geology & Exploration

In order to reveal the heat transfer performance of the horizontal buried pipe heat exchanger in the ground source heat pump system in different soil types, this paper, based on the theoretical knowledge of soil capillary water, combined with the means of numerical simulation, discusses the influence of the difference of three-phase composition in different types of energy storage soil on the heat transfer characteristics of the horizontal buried pipe heat exchanger. The results show that under the cooling condition of 308.15 K, the outlet water temperature of the horizontal pipe in the loam soil decreases to 303.3 K and …

Development And Prospect Of Intelligent Drilling Technology And Equipment For Underground Coal Mines In China, Li Quanxin, Liu Fei, Fang Jun Xi'an Research Institute Co., Ltd., China Coal Technology And Engineering Group Corp., Xi'an 710077, China, Liu Jianlin, Chu Zhiwei

Coal Geology & Exploration

The intelligent drilling technology and equipment are important part of the intelligent construction of coal mine, and it is the advanced technology and equipment urgently needed by coal mine enterprises to further promote the work of reducing personnel and increasing efficiency. The phased achievements of underground intelligent drilling technology and equipment during the 13th five-year plan are systematically summarized, and the development status of key technical equipment such as automatic drilling rig, parameter monitoring of measurement while drilling(MWD) system, rotary steerable system are introduced. The key factors restricting the research and development (R & D) and application of intelligent drilling …

Prediction Of Fracture Distribution And Evaluation Of Shale Gas Preservation Conditions In Longmaxi Formation In Dongxi Area, Xie Jiatong, Fu Xiaoping, Qin Qirong, Li Hu

Coal Geology & Exploration

Commercial development of shale gas confirmed that mature shale has great potential for exploration, southeast Sichuan is the strategic pilot area of shale gas exploration and development in southern China, cracks are the key factor of shale gas preservation and development deployment, for the structural environment complex and special basin edge area, increasing the difficulty of shale crack research, but also provides a new direction for shale gas exploration and development. As a new field of oil and gas exploration in China, shale gas exploration has not yet developed a mature crack evaluation system. Taking Dongxi area of the southeast …

Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong

Coal Geology & Exploration

In order to reveal the micro-pore structure characteristics of marine-continental transitional shale and its main controlling factors in the eastern margin of Ordos Basin, and to enrich the understanding of pore development characteristics and pore structure of marine-continental transitional coal-bearing shale in the block, scanning electron microscope, high-pressure mercury injection and liquid nitrogen adsorption analysis were used to characterize the micro-pore structure characteristics of shale in Linxing area. Furthermore, porosity, total content of organic carbon, mineral content, clay relative content and organic matter maturity were tested to study the main controlling factors of development of shale pore structure. The results …

Characteristics Of Shallow Coal Measure Gas Reservoir And Key Technologies Of Exploration And Development In Yaojie Mining Area, Du Xinfeng, Yuan Chongliang, Wang Zhengxi, Wang Junde, Li Shibing, Liu Jingdan, He Xiuqing, Zhang Tianguo, Shan Yuanwei, Fang Jiawei

Coal Geology & Exploration

The exploration and development of coal measures gas can not only effectively improve the single well production of coalbed methane in coal mining areas, reduce the waste of resources, but also alleviate the energy crisis in China, reduce coal mine gas accidents, protect the atmospheric environment, and contribute to the realization of carbon peak and carbon neutralization. Based on the shallow coal measure gas development demonstration project in the third mining area of Haishiwan mine field, the characteristics of coal measure gas reservoirs in Yaojie mining area are analyzed, and the key technologies for coal-measure gas exploration and development are …

Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan

Coal Geology & Exploration

A seismic physical simulation is carried out for the complex seismic response of the coal seam of Yan'an Formation in the loess tableland. First, the physical model materials for the dry layer near the surface of the loess tableland and the coal seam are developed. After several tests, a mixture of silicone rubber with silicon aerogel powder is selected to simulate the surface of the loess tableland, and the mixture with ultra-fine carbon powder added to silicone rubber is used to simulate the low-speed and low-density coal seam. Through the methods of molds control layer, layer by layer pouring, three-dimensional …

Factors Affecting The Attitude Accuracy Of Wireless Electromagnetic Wave Mwd System, Wang Xiaobo

Coal Geology & Exploration

In broken soft coal seams of coal mine where hydraulic driving directional drilling is used, hole collapse and hole wall instability are easy to occur. Electromagnetic wave measurement while drilling system is suitable for gas driving drilling, so it is widely used in broken soft coal seams. The accuracy of drilling trajectory is the key to gas drainage effect in broken soft coal seams. In the use of electromagnetic wave measurement while drilling system, the phenomenon of insufficient accuracy and large error of trajectory measurement appears irregularly. In order to solve this problem, this paper analyzes all the factors that …

Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei

Coal Geology & Exploration

To investigate the influence of lime content on loess strength and its microscopic mechanism, different proportions of lime were used to improve loess. Through direct shear test, mercury intrusion porosimetry and scanning electron microscopy, the strength characteristics and microstructure changes of compacted loess and modified loess with different lime contents were analyzed qualitatively and quantitatively, and the microscopic mechanism of lime-improved loess was analyzed in depth. The results show that the shear strength parameters of lime-improved loess increases first and then decreases with the increase of lime contents. The cohesive force and internal friction angle reach the maximum when the …

Characteristics Of The Shale Gas Reservoirs And Evaluation Of Sweet Spots In Wufeng Formation And Longmaxi Formation In Jingmen Exploration Area, Li Xiaoming, Liu Jirong, Lin Wen, Ma Lihong, Liu Dexun, Chen Yujie

Coal Geology & Exploration

In order to further clarify the resource potential of shale gas from Wufeng Formation to Longmaxi Formation in Jingmen exploration area, sweet spots were selected. The shale in Wufeng Formation and 1th Member of Longmaxi Formation of the well X was taken as the research object in this study. Using sliced kerogen, X-ray diffraction, nuclear magnetic resonance, micro nano CT scanning, geochemical analysis and other testing methods, combined with logging interpretation results, based on the petrology, organic geochemical and mineral composition, physical properties, pore types and structure characteristics and hydrocarbon content, the reservoir characteristics of Wufeng-1^th Member of the …