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2020

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Articles 91 - 120 of 15205

Full-Text Articles in Physical Sciences and Mathematics

Step-By-Step Modification Of Graphite Felt Electrode For Vanadium Redox Flow Battery, Jing-Yuan Lou, Dong-Jiang You, Xue-Jing Li Dec 2020

Step-By-Step Modification Of Graphite Felt Electrode For Vanadium Redox Flow Battery, Jing-Yuan Lou, Dong-Jiang You, Xue-Jing Li

Journal of Electrochemistry

As a well-known electrode material of the vanadium redox flow battery (VRFB),graphite felt electrode is the frequently-used electrode material in VRFB, and its low electrochemical activity is one of the key factors for the low power density of VRFB. In this work, we proposed a step-by-step modification method, which used KMnO4 to oxidize graphite felt first and then placed in an activation solution to excite its reactivity, to improve the electrochemical performance of the graphite felt electrode. According to the results from cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) characterizations …

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Core-Shell Structured Ru@Ptru Nanoflower Electrocatalysts Toward Alkaline Hydrogen Evolution Reaction, Xue-Liang Wang, Yuan-Yuan Cong, Chen-Xi Qiu, Sheng-Jie Wang, Jia-Qi Qin, Yu-Jiang Song Dec 2020

Core-Shell Structured Ru@Ptru Nanoflower Electrocatalysts Toward Alkaline Hydrogen Evolution Reaction, Xue-Liang Wang, Yuan-Yuan Cong, Chen-Xi Qiu, Sheng-Jie Wang, Jia-Qi Qin, Yu-Jiang Song

Journal of Electrochemistry

Water electrolysis for hydrogen production is beneficial for solving the problem of energy crisis and environmental issues. It is necessary to study highly active and cost-effective catalysts toward hydrogen evolution reaction (HER) to reduce the consumption of noble metals. Herein, we report the synthesis of core-shell structured Ru@Pt0.24Ru nanoflowers electrocatalyst by stepwise reduction of Ru and Pt precursors in the mixture of oleylamine and benzyl alcohol at 160 oC. The average diameter of the resultant Ru@Pt0.24Ru was 16.5±4.0 nm with a bulk atomic ratio between Pt and Ru of 0.24:1 and a surface ratio of …

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Preparation And Process Optimization Of Cathode Materials For Lithium-Sulfur Batteries, Kai Wu Dec 2020

Preparation And Process Optimization Of Cathode Materials For Lithium-Sulfur Batteries, Kai Wu

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries represent promising candidates for next-generation energy storage system due to their high energy density and low material cost. However, the industrial application of Li-S batteries remains challenges because of the shuttle effect from lithium polysulfides and the lack of facial routes for Li-S battery preparation. To solve these problems, a cathode consisting of different commercial carbon materials, namely, acetylene black (SP), Ketjen Black (KB) and carbon nanotube (CNT), with sulfur (S) is prepared separately for Li-S battery. After the process of 8-h ball milling for KB/S composite, together with the polyvinyl pyrrolidone (PVP) binder, the cathode could …

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Synergistic Effect Of Dissolving O2 And Wavelength On The Photo-Assisted Anodic Deposition Of Ceo2 Thin Films, Tong-Zheng Jin, Yu-Meng Yang, Sheng-Hui Fan, Guo-Ying Wei, Zhao Zhang Dec 2020

Synergistic Effect Of Dissolving O2 And Wavelength On The Photo-Assisted Anodic Deposition Of Ceo2 Thin Films, Tong-Zheng Jin, Yu-Meng Yang, Sheng-Hui Fan, Guo-Ying Wei, Zhao Zhang

Journal of Electrochemistry

Cerium dioxide (CeO2) thin films have been applied as new material in many technical fields such as solid oxide fuel cells, catalysts, UV absorbents, pharmacology, and coatings for corrosion protection of many metals and alloys. Electrodeposition is widely considered to be one of the best preparation methods for CeO2 film. In this work, the CeO2 films were prepared by photo-assisted anodic deposition in the bath solutions containing 0.05 mol·L-1 cerium (III) nitrate, 0.1 mol·L-1 ammonia acetate and 70% (V/V) ethanol onto 316L stainless steel (SS) surface. The synergistic effects of …

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Electrochemical Determination Of Dopamine Based On Metal-Substituted Polyoxometalates Composites, Yi-Fei Xing, Na Li, Xiao-Fang Wen, Hong-Yan Han, Min Cui, Cong Zhang, Ju-Jie Ren, Xue-Ping Ji Dec 2020

Electrochemical Determination Of Dopamine Based On Metal-Substituted Polyoxometalates Composites, Yi-Fei Xing, Na Li, Xiao-Fang Wen, Hong-Yan Han, Min Cui, Cong Zhang, Ju-Jie Ren, Xue-Ping Ji

Journal of Electrochemistry

In this report, a dopamine electrochemical sensor based on metal-substituted polyoxometalates and reduced graphene oxide (RGO) composite was successfully constructed. The K2H2SiW11NiO39·xH2O (SiW11Ni) was synthesized by hydrothermal method, while the RGO was prepared by Hummers' method and chemical reduction method. The above-mentioned materials were characterized by SEM, FTIR and XRD. The as-synthesized SiW11Ni and RGO composites were modified on the surface of glassy carbon electrode (GCE) by drop coating method, and the sensing interface (SiW11Ni-RGO/GCE) was successfully constructed. The electrochemical properties of …

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Evaluating Alternative Livestock Production Systems Sustainability And Farmer Income In Taipusi Banner, Inner Mongolia, Q. Tian, R. Jones, David L. Michalk, Geoff D. Millar, David R. Kemp, Z. Xu, J. Xie, Y. Zheng Dec 2020

Evaluating Alternative Livestock Production Systems Sustainability And Farmer Income In Taipusi Banner, Inner Mongolia, Q. Tian, R. Jones, David L. Michalk, Geoff D. Millar, David R. Kemp, Z. Xu, J. Xie, Y. Zheng

IGC Proceedings (1993-2023)

No abstract provided.

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Effect Of Feed Restriction On Compensatory Growth And Body Dimensions In Ujumuqin Lambs, Jiayin Song, Daowei Zhou, Ping Wang Dec 2020

Effect Of Feed Restriction On Compensatory Growth And Body Dimensions In Ujumuqin Lambs, Jiayin Song, Daowei Zhou, Ping Wang

IGC Proceedings (1993-2023)

No abstract provided.

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The Weight Variations Of Grazing Goats And Sheep In The Desert Steppe In Winter And Spring, Y. M. Shan, Mingjiu Wang, H. J. Chen, Zh. Y. Wu, Zh. Q. Li, X. L. Sun, Zh. Yang Dec 2020

The Weight Variations Of Grazing Goats And Sheep In The Desert Steppe In Winter And Spring, Y. M. Shan, Mingjiu Wang, H. J. Chen, Zh. Y. Wu, Zh. Q. Li, X. L. Sun, Zh. Yang

IGC Proceedings (1993-2023)

No abstract provided.

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Pasture Management Reshaping Dairy Cows Grazing Behavior And Performance, A. Schmitt, W. Murphy Dec 2020

Pasture Management Reshaping Dairy Cows Grazing Behavior And Performance, A. Schmitt, W. Murphy

IGC Proceedings (1993-2023)

No abstract provided.

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Home Range Size Of Free‐Roaming Beef Suckler Cattle In The Forest, Shusuke Sato, Yoshitaka Deguchi, Takeshi Yasue, Takami Kosako Dec 2020

Home Range Size Of Free‐Roaming Beef Suckler Cattle In The Forest, Shusuke Sato, Yoshitaka Deguchi, Takeshi Yasue, Takami Kosako

IGC Proceedings (1993-2023)

No abstract provided.

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Evaluation Of Lamb Performance And Forage Quality In Rotational Grazing Systems, Yuping Rong, L. X. Zhao Dec 2020

Evaluation Of Lamb Performance And Forage Quality In Rotational Grazing Systems, Yuping Rong, L. X. Zhao

IGC Proceedings (1993-2023)

No abstract provided.

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Lactating Grazing Dairy Cow Performance: Influence Of Chopped Fresh Maize Supplementation, M. Ramírez‐Mella, O. Hernández‐Mendo, R. Amendola‐Mashiotti, D. G. Mendoza‐Martinez, J. E. Ramirez‐Bibriesca Dec 2020

Lactating Grazing Dairy Cow Performance: Influence Of Chopped Fresh Maize Supplementation, M. Ramírez‐Mella, O. Hernández‐Mendo, R. Amendola‐Mashiotti, D. G. Mendoza‐Martinez, J. E. Ramirez‐Bibriesca

IGC Proceedings (1993-2023)

No abstract provided.

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Seasonal Occurrence Of Bovine Mastitis Causing Organisms From Grazing Land Of Western Ghats, India, M. Mardhu Ramachandran, M. Andrew Pardeep, T. R. Prabha Dec 2020

Seasonal Occurrence Of Bovine Mastitis Causing Organisms From Grazing Land Of Western Ghats, India, M. Mardhu Ramachandran, M. Andrew Pardeep, T. R. Prabha

IGC Proceedings (1993-2023)

No abstract provided.

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Luis I. Prádanos. Postgrowth Imaginaries: New Ecologies And Counterhegemonic Culture In Post-2008 Spain. Liverpool Up, 2018., Shanna Lino Dec 2020

Luis I. Prádanos. Postgrowth Imaginaries: New Ecologies And Counterhegemonic Culture In Post-2008 Spain. Liverpool Up, 2018., Shanna Lino

Studies in 20th & 21st Century Literature

Review of Luis I. Prádanos. Postgrowth Imaginaries: New Ecologies and Counterhegemonic Culture in Post-2008 Spain. Liverpool UP, 2018. 246 pp.

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Signature Identification And Verification Systems: A Comparative Study On The Online And Offline Techniques, Nehal Hamdy Al-Banhawy, Heba Mohsen, Neveen I. Ghali Prof. Dec 2020

Signature Identification And Verification Systems: A Comparative Study On The Online And Offline Techniques, Nehal Hamdy Al-Banhawy, Heba Mohsen, Neveen I. Ghali Prof.

Future Computing and Informatics Journal

Handwritten signature identification and verification has become an active area of research in recent years. Handwritten signature identification systems are used for identifying the user among all users enrolled in the system while handwritten signature verification systems are used for authenticating a user by comparing a specific signature with his signature that is stored in the system. This paper presents a review for commonly used methods for preprocessing, feature extraction and classification techniques in signature identification and verification systems, in addition to a comparison between the systems implemented in the literature for identification techniques and verification techniques in online and …

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Schrödinger-Poisson Systems With Singular Potential And Critical Exponent, Senli Liu, Haibo Chen, Zhaosheng Feng Dec 2020

Schrödinger-Poisson Systems With Singular Potential And Critical Exponent, Senli Liu, Haibo Chen, Zhaosheng Feng

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this article we study the Schrödinger-Poisson system−∆ u+ V (| x|) u+ λφu= f (u), x∈ R3,−∆ φ= u2, x∈ R3, where V is a singular potential with the parameter α and the nonlinearity f satisfies critical growth. By applying a generalized version of Lions-type theorem and the Nehari manifold theory, we establish the existence of the nonnegative ground state solution when λ= 0. By the perturbation method, we obtain a nontrivial solution to above system when λ= 0.

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Evaluation Of Forages And Soils In Different Waterlogged Saline Grasslands In Western And Southern Coastal Region Of Sri Lanka, Sujatha Premaratne, G. G. C. Premalal Dec 2020

Evaluation Of Forages And Soils In Different Waterlogged Saline Grasslands In Western And Southern Coastal Region Of Sri Lanka, Sujatha Premaratne, G. G. C. Premalal

IGC Proceedings (1993-2023)

No abstract provided.

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Use Of Intensive Fodder Banks With Hybrid Napier Co‐3grass For Smallholder Dairy Production Systems In The Dry Zone Of Sri Lanka, G. G. C. Premalal, Sujatha Premaratne, Anil Jayawardena Dec 2020

Use Of Intensive Fodder Banks With Hybrid Napier Co‐3grass For Smallholder Dairy Production Systems In The Dry Zone Of Sri Lanka, G. G. C. Premalal, Sujatha Premaratne, Anil Jayawardena

IGC Proceedings (1993-2023)

No abstract provided.

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Analysis On Factors Affecting Alfalfa Survival Of Overwintering Seedlings In The East Of Southern Daxinganling, China, Baojun Ning, Yulan Zhang Dec 2020

Analysis On Factors Affecting Alfalfa Survival Of Overwintering Seedlings In The East Of Southern Daxinganling, China, Baojun Ning, Yulan Zhang

IGC Proceedings (1993-2023)

No abstract provided.

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Spatial Distribution Of Forage Intake By Grazing Beef Cows On An Alpine Pasture In Japan, M. Nakano, Masato Yayota, R. Tamai, Shigeru Ohtani Dec 2020

Spatial Distribution Of Forage Intake By Grazing Beef Cows On An Alpine Pasture In Japan, M. Nakano, Masato Yayota, R. Tamai, Shigeru Ohtani

IGC Proceedings (1993-2023)

No abstract provided.

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Numerical Simulation Of Nonlinear Vibrations Of Discrete Mass With Harmonic Force Perturbation, M. Yusupov, B. A. Akhmedov, Olga Karpova Dec 2020

Numerical Simulation Of Nonlinear Vibrations Of Discrete Mass With Harmonic Force Perturbation, M. Yusupov, B. A. Akhmedov, Olga Karpova

Acta of Turin Polytechnic University in Tashkent

The problem of vibration of a single-mass system under the force excitation of vibration associated with a fixed base by a weightless nonlinear viscoelastic spring is considered. To take into account the rheological properties of the spring material, the Boltzmann-Volterra principle was used. Mathematical models of the problem under consideration are obtained, which are described by integro-differential equations. A solution method based on the use of quadrature formulas has been developed and a computer program has been compiled on its basis, the results obtained are presented in the form of graphs. The influence of nonlinear and rheological properties of a …

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Salt Marsh Elevation Limit Determined After Subsidence From Hydrologic Change And Hydrocarbon Extraction, R. Eugene Turner, Yu Mo Dec 2020

Salt Marsh Elevation Limit Determined After Subsidence From Hydrologic Change And Hydrocarbon Extraction, R. Eugene Turner, Yu Mo

Faculty Publications

Levee construction aboveground and hydrocarbon removal from belowground in coastal wetlands can create hydrologic changes that increase plant stress through flooding. But the significance of the subsidence they cause individually or in combination is contested. This study untangled them to demonstrate elevational limits of salt marshes by studying dredged and natural waterways in two salt marshes in Louisiana, USA. The areas had a homogenous plant cover before drilling for oil and gas extraction peaked in the 1960s, and now are a mixed network of natural waterways and dredged canals used to drill wells with an average drill date of 1965.8 …

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Evolution Of Magnetic-Field-Induced Ordering In The Layered Structure Quantum Heisenberg Triangular-Lattice Antiferromagnet Ba3Cosb2O9, Nathanael Alexander Fortune, Q. Huang, T. Hong, J. Ma, E. S. Choi, S. T. Hannahs, Z. Y. Zhao, X. F. Sun, Y. Takano, H. D. Zhou Dec 2020

Evolution Of Magnetic-Field-Induced Ordering In The Layered Structure Quantum Heisenberg Triangular-Lattice Antiferromagnet Ba3Cosb2O9, Nathanael Alexander Fortune, Q. Huang, T. Hong, J. Ma, E. S. Choi, S. T. Hannahs, Z. Y. Zhao, X. F. Sun, Y. Takano, H. D. Zhou

Physics: Faculty Publications

Quantum fluctuations in the effective spin-1/2 layered structure triangular-lattice quantum Heisenberg antiferromagnet Ba3CoSb2O9 lift the classical degeneracy of the antiferromagnetic ground state in magnetic field, producing a series of novel spin structures for magnetic fields applied within the crystallographic ab plane, including a celebrated collinear ‘up-up-down’ spin ordering with magnetization equal to 1/3 of the saturation magnetization over an extended field range. Theoretically unresolved, however, are the effects of interlayer antferromagnetic coupling and transverse magnetic fields on the ground states of this system. Additional magnetic-field-induced phase transitions are theoretically expected and in some cases have …

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Technology And Application Of High Efficiency Gas Extraction By Directional Long Borehole Hydraulic Fracturing In Coal Seams Of Medium Hardness And Low Permeability, Guo Chaoqi, Zhao Jizhan, Li Xiaojian, Zhang Jingfei, Wu Shengli, Chen Dongdong, Huang Xingli, Li Baojun Dec 2020

Technology And Application Of High Efficiency Gas Extraction By Directional Long Borehole Hydraulic Fracturing In Coal Seams Of Medium Hardness And Low Permeability, Guo Chaoqi, Zhao Jizhan, Li Xiaojian, Zhang Jingfei, Wu Shengli, Chen Dongdong, Huang Xingli, Li Baojun

Coal Geology & Exploration

Grouting quality test is the key technology for efficient development and utilization of waste land in the goaf of a coal mine, it is of great significance to evaluate the stability of the site and the safety of construction after goaf management. Based on many engineering practices, this paper summarizes the evaluation method of the qualified standards of the grouting quality and the errors existed in the testing work. The results proved that the quality inspection after grouting is a systematic work. The test method could be optimized according to the characteristics of the construction and grouting design requirements, following …

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Research Status And Thoughts For Coal Fines During Cbm Development, Wei Yingchun, Zhang Jin, Cao Daiyong, Meng Tao, Cui Maolin, Wang Anmin Dec 2020

Research Status And Thoughts For Coal Fines During Cbm Development, Wei Yingchun, Zhang Jin, Cao Daiyong, Meng Tao, Cui Maolin, Wang Anmin

Coal Geology & Exploration

Artificial freezing is a commonly used method for stopping water and providing temporary support during the excavation of saturated sand. This study on the damage characteristics of frozen soil lays the foundation for the analysis of the mechanical properties of frozen soil and the stability of frozen bodies. In order to study the damage mechanical properties of frozen sand, three-dimensional laboratory tests on frozen sand with different intermediate principal stress coefficients were carried out at -5℃. Based on the Weibull random distribution of micro element failure of frozen soil, the Drucker-Prager strength criterion was invoked as the statistical distribution variable, …

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Pattern And Effect Of The High Density 3d Seismic Exploration In Coal Mining Districts, Jin Xueliang, Wang Qi Dec 2020

Pattern And Effect Of The High Density 3d Seismic Exploration In Coal Mining Districts, Jin Xueliang, Wang Qi

Coal Geology & Exploration

Graphene is an emerging carbon nanomaterial in the 21st century, has excellent properties and shows great application potential in many fields. Coal is the most abundant and the cheapest carbon source with unique structure and material composition. The application of coal in the development and the application of new carbonaceous materials such as graphene and their composites is a work worthy of further exploration. The development of coal-based graphene can both promote the clean utilization of coal and enhance the added value of coal resources. In this paper, the research developments in coal structure, the mechanism of coal graphitization, as …

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Seismic Attribute Recognition Technology Of Magmatic Rock Intrusive Coal Seam, Wu Bin, Meng Fanbin Dec 2020

Seismic Attribute Recognition Technology Of Magmatic Rock Intrusive Coal Seam, Wu Bin, Meng Fanbin

Coal Geology & Exploration

In order to increase the degree of production of CBM development blocks, when the production of a single well enters a decline period, the development plan needs to be adjusted, and the production increase and stability can be achieved through the measures such as layer adjustment or layer compensation. In terms of time, it is believed that the main coal seam should be developed first when it is put into production. After the decline period, the secondary main coal seam should be supplemented and combined; in space, combined with the development dynamics, the analytic hierarchy process is used to determine …

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High Rank Coal Structure And Log Interpretation Method Of Fracture Pressure In Shouyang Block, Li Songlin, Li Zhongcheng, Wang Lina, Duan Jing, Xiang Nian Dec 2020

High Rank Coal Structure And Log Interpretation Method Of Fracture Pressure In Shouyang Block, Li Songlin, Li Zhongcheng, Wang Lina, Duan Jing, Xiang Nian

Coal Geology & Exploration

In order to accurately describe the distribution of surface subsidence basin, and based on the power exponential function model and the subsidence features, the surface subsidence basin model of long-wall working face along strike with gently inclined coal seam was established concerned the combination of theoretical analysis and numerical simulation method. The influencing factors of model parameters and the changing patterns of parameters were analyzed, and the applicability and the predicting accuracy of the model were verified. The results showed that parameter n reflected the range of the bottom size of the sinking basin, which was mainly related to the …

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Construction And Transformation Technology Of Three-Dimensional Fine Model Of Mine Water Diversion Structure, Fan Juan, Hou Enke, Jin Dewu, Qiao Wei, Nan Shenghui Dec 2020

Construction And Transformation Technology Of Three-Dimensional Fine Model Of Mine Water Diversion Structure, Fan Juan, Hou Enke, Jin Dewu, Qiao Wei, Nan Shenghui

Coal Geology & Exploration

The development degree of natural fractures is the main factor affecting coalbed methane productivity. In order to accurately obtain the distribution position of the natural fractures in the a coalbed methane field in the southern Qinshui basin, 7 refracturing wells in the area were adopted by surface microseismic vector scanning to monitor the natural fractures. A certain amount of three-component geophones were deployed around the fracturing well to collect microseismic events in the surrounding reservoir during fracturing, and after Semblance superposition, the fracture energy slices at different times in the monitoring area were obtained to explain the natural fractures in …

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Table Of Contents, The Editors Dec 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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