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2022

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Shear Characteristics And Modified Coulomb Model Of Alfalfa Root-Loess Composite, Duan Zhao, Yuan Lin, Bi Yinli, Wang Kai, Wu Yanbin, Zhang Qing Dec 2022

Shear Characteristics And Modified Coulomb Model Of Alfalfa Root-Loess Composite, Duan Zhao, Yuan Lin, Bi Yinli, Wang Kai, Wu Yanbin, Zhang Qing

Coal Geology & Exploration

Plant roots can significantly improve the strength of soil. In order to explore the enhancement effect of alfalfa root on the shear strength of loess, study was conducted based on the root-soil composites of alfalfa with a growth period of 60 d herein. Specifically, the parameters on shear strength of the alfalfa root-soil composite and the tensile strength of alfalfa root were obtained through the direct shear tests and root tensile tests. By observing the structure and characteristics of alfalfa root with an electronic magnifier, a modified Coulomb model of root-soil composite was established with the empirical formula. Meanwhile, the …

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Discussion On Identification Standard Of Coal-Measure Graphite, Cao Daiyong, Wang Lu, Zhu Wenqing, Wu Guoqiang, Wei Yingchun, Ning Shuzheng, Wang Guixiang, Xiao Jincheng, Xu Xiang, Liu Kang Dec 2022

Discussion On Identification Standard Of Coal-Measure Graphite, Cao Daiyong, Wang Lu, Zhu Wenqing, Wu Guoqiang, Wei Yingchun, Ning Shuzheng, Wang Guixiang, Xiao Jincheng, Xu Xiang, Liu Kang

Coal Geology & Exploration

The identification and classification of coal-measure graphite are the precondition and basic work of mineral geological exploration, as well as resource exploitation and utilization. The preparation of identification standards of coal-measure graphite should follow the principles of science, systematicness, applicability and operability. Coal graphitization and coalification is a continuous progression plus jump process, and the characteristics of coal-measure graphite, including the step evolution of macromolecular structure and the heterogeneity of material composition, leads to the complexity of ore identification. In order to establish the scientific and practical identification standards, and from the study of metallogenic mechanism and the demand of …

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Experimental Research On Mechanical Properties Of “Jacked Pipe-Frozen Soil” Composite Structure In Freeze-Sealing Pipe Roof Tunnel, Duan Yin, Rong Chuanxin, Cai Haibing, Long Wei Dec 2022

Experimental Research On Mechanical Properties Of “Jacked Pipe-Frozen Soil” Composite Structure In Freeze-Sealing Pipe Roof Tunnel, Duan Yin, Rong Chuanxin, Cai Haibing, Long Wei

Coal Geology & Exploration

As the key project of Zhuhai Connecting Line of Hong Kong‒Zhuhai‒Macao Bridge, the underground excavation section of Gongbei Tunnel has applied the freeze-sealing pipe roof method for the first time. Combining the advantages of the pipe roof method and the artificial ground freezing method, this method could form a “jacked pipe-frozen soil curtain” composite support system on the tunnel section, so as to effectively achieve the dual goals of “bearing” and “water-stopping between pipes”, thereby ensuring that stability and safety during tunnel excavation. To obtain the temperature, deformation and mechanical properties of the “jacked pipe-frozen soil” composite structure, a set …

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Path Planning Of Coal Mine Rescue Robot Based On Improved A* Algorithm, Zhang Weimin, Zhang Yue, Zhang Hui Dec 2022

Path Planning Of Coal Mine Rescue Robot Based On Improved A* Algorithm, Zhang Weimin, Zhang Yue, Zhang Hui

Coal Geology & Exploration

A coal mine rescue robot that performs a rescue task needs to obtain the environment model and plan a collision-free path from the current location to the target location with the built-in algorithm upon receiving a task instruction. In order to reduce the moving time of the rescue robot, the path is usually required to be time-optimal. However, the path planned by the conventional A* algorithm that is widely used at present under the grid map environment has many problems, such as many path redundancy points and large turning angle, which leads to the fact that the path is suboptimal …

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Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke Dec 2022

Fault Diagnosis Of Hydraulic Power System For Coal Mine Tunnel Drilling Rig Based On T-S Fuzzy Fault Tree, Liu Ruojun, Zhang Youzhen, Yao Ke

Coal Geology & Exploration

In view of the problems of fuzzy logic relation between the elements of the system, the polymorphism of fault mode, and the difficulty in obtaining the fault probability as a result of the complication of the hydraulic power system for coal mine tunnel drilling rig, a fault diagnosis method of hydraulic power system for coal mine tunnel drilling rig based on Takagi-Sugeno (T-S) fuzzy tree was proposed to overcome the limitations of traditional fault tree in fault diagnosis and analysis of the complex electromechanical hydraulic equipment. The method could timely and accurately obtain the fault information of equipment, and to …

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Experimental Study On Effect Of Soil Layer Reconstruction And Inoculation On Plant Root Hydraulic Lift In Open-Pit Coal Mine Dump, Bi Yinli, Gao Xuejiang, Ke Zengming, Xiao Li Dec 2022

Experimental Study On Effect Of Soil Layer Reconstruction And Inoculation On Plant Root Hydraulic Lift In Open-Pit Coal Mine Dump, Bi Yinli, Gao Xuejiang, Ke Zengming, Xiao Li

Coal Geology & Exploration

Soil layer reconstruction of open-pit coal mine dump is of great significance for ecological reconstruction. In order to study the effect of inoculation of dark septate endophytes (DSE) on water utilization of corn root system under different reconstructed soil layer models, soil column simulating and culturing test was adopted, with DSE inoculation and control treatment set up under each of the four soil layer types, in a total of 8 groups. The results show that the roots of corn are the longest with the maximum density under the treatment with 20% loess, which are 3.2, 2.4 and 2.8 times that …

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Effect Of Coal Mining Subsidence Fractures On Source Of Water Absorption Of Artemisia Desertorum, Shang Jingxuan, Chen Shi, Liu Qianwen, Guo Xufeng, Guo Junting, Li Mi Dec 2022

Effect Of Coal Mining Subsidence Fractures On Source Of Water Absorption Of Artemisia Desertorum, Shang Jingxuan, Chen Shi, Liu Qianwen, Guo Xufeng, Guo Junting, Li Mi

Coal Geology & Exploration

Ground fissures caused by coal mining subsidence are not only a serious geological hazard, but also affect the growth and development of vegetation in the mining area and damage the mining ecosystem. To investigate the quantitative influence of coal mining subsidence fractures on the source of water uptaken by Artemisia Desertorum, the simulated precipitation tests of isotopically-labeled water were conducted in three test areas influenced by coal mining subsidence fractures to different degrees on 22312-working face of Huojitu mine field in Shendong mining area. The three test areas were divided according to the distance between Artemisia Desertorum and the fractures, …

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Prediction Method And Application Of Gas Emission From Mining Workface Based On Stl-Eemd-Ga-Svr, Lin Haifei, Liu Shihao, Zhou Jie, Xu Peiyun, Shuang Haiqing Dec 2022

Prediction Method And Application Of Gas Emission From Mining Workface Based On Stl-Eemd-Ga-Svr, Lin Haifei, Liu Shihao, Zhou Jie, Xu Peiyun, Shuang Haiqing

Coal Geology & Exploration

Accurate prediction of gas emission can provide important basis for mine ventilation and the prevention and measures of gas disasters. In order to improve the prediction accuracy of gas emission in the mining workface, the monitoring data of gas emission were decomposed into the trend term, periodic term and irregular fluctuation term by the Seasonal-Trend decomposition procedure based on Loess (STL) based on the monitoring data of gas emission from the mining workface of Huangling Mine in Shaanxi. Besides, the irregular fluctuation term was further broken down into the Intrinsic Mode Functions (IMFs) components with different characteristics and the residual …

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The Early College Research Tradition And The People Who Made It: A History Of Interventions That Shaped The Field, Russ Olwell Dec 2022

The Early College Research Tradition And The People Who Made It: A History Of Interventions That Shaped The Field, Russ Olwell

Early College Folio

Early college as an educational reform has had a unique trajectory over the past two decades. School reform in the United States (with a few exceptions) has been a top-down movement, and the majority of attention has centered on grades three through eight, the grade levels the No Child Left Behind Act focused on. Early college, by contrast, has been a grassroots movement in many areas and has focused on high school students and their aspirations for college. This article describes the story of early college through the lens of individuals whose research helped to reorient the field and broaden …

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Research On The Innovation Mechanism Of Online Food Safety Supervision From The Perspective Of Holistic Governance, Li Xi Dec 2022

Research On The Innovation Mechanism Of Online Food Safety Supervision From The Perspective Of Holistic Governance, Li Xi

Food and Machinery

Holistic governance theory is a new type of public management strategy, which helps to provide citizens with a seamless and non-separated holistic service governance scheme, and provides new ideas for food safety supervision. Based on the theory of holistic governance, this article proposes three levels of online food safety supervision, from the perspective of the integrity of supervision implementation to reconstruct the execution network, the integrity of the supervision body to reconfigure of the participating network, the integrity of the supervision accountability to reshape of the power and responsibility system.

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Assessing Arrest & Traffic Stop Patterns In Portland, Me, Jack Mcdevitt Ph.D., George Shaler Mph, Sarah Krichels Goan Mpp, Stephen Abeyta, Carlos Cuevas Phd Dec 2022

Assessing Arrest & Traffic Stop Patterns In Portland, Me, Jack Mcdevitt Ph.D., George Shaler Mph, Sarah Krichels Goan Mpp, Stephen Abeyta, Carlos Cuevas Phd

Publications

This project examined the available arrest and traffic citation data from Portland Police Department to determine if there is any evidence of disproportionate enforcement activities in the city.

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Mathematics In Indian Music: Examining Children’S Learning Process, Smita Guha Dec 2022

Mathematics In Indian Music: Examining Children’S Learning Process, Smita Guha

Journal of Global Awareness

There are many mathematical concepts found in music. Music is integrated into Indian culture. It is a common practice among children in India to engage in music lessons from a young age. The purpose of this study was to investigate the impact of Indian music on the cognitive development of children to understand or reinforce mathematics. Data was collected from three schools in Kolkata, India, through interviews, observations, and survey questionnaires. Six different music classes from three music schools were observed at different times. Observations were documented through pictures, video recordings, running records, and anecdotal records. To supplement these documentations, …

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Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss Dec 2022

Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss

Theses and Dissertations

With the increase in the use of UAS (Unmanned Aerial Systems) for marine mammal research, there is a need for the development of methods of analysis to transform UAS high resolution video into quantitative data. This study sought to develop a preliminary method of analysis that would quantify and present a way to visualize the dynamics and relative spatial distribution and changes in distribution of bottlenose dolphins (Tursiops truncatus) in the waters of Turneffe Atoll, Belize. This approach employs a previously developed video tracking program ‘Keypoint Tracking’ that enables manual tracking of individual dolphins and the creation of …

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Evolution Law Of Water Inflow In Full Life Cycle Of Working Face In Deep Buried Inner Mongolia-Shaanxi Mining Area, Liu Yang, Yang Jian, Zhou Jianjun Dec 2022

Evolution Law Of Water Inflow In Full Life Cycle Of Working Face In Deep Buried Inner Mongolia-Shaanxi Mining Area, Liu Yang, Yang Jian, Zhou Jianjun

Coal Geology & Exploration

The deep buried Inner Mongolia-Shaanxi mining area was newly developed, where the hydrogeological characteristics under the disturbance of coal mining were still unclear. Various types of water damage problems had occurred in the process of infrastructure construction and production. Among them, no research was conducted for the variation characteristics of water inflow during and after mining in working face, which increased the difficulty in the arrangement of underground water drainage system and the work of water prevention and control. In order to find out the evolution law of water inflow in the full life cycle of working face before and …

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Study On Performance Optimization Of Gasification Slag Based Paste Filling Materials In Ningdong Mining Area, Chen Denghong, Li Chao, Zhang Zhiguo Dec 2022

Study On Performance Optimization Of Gasification Slag Based Paste Filling Materials In Ningdong Mining Area, Chen Denghong, Li Chao, Zhang Zhiguo

Coal Geology & Exploration

As one of the nine coal bases at hundred million ton level in Yellow River Basin, Ningdong Mining Area has nearly 2×108 t of coal-based solid waste produced annually, and faces to the problems of large stock of gasification slag, difficulty in scaled utilization, and limited space for simple landfill. Filling mining could solve the problem of stockpiling, of which the cost is high and the performance needs to be optimized. According to the response surface method, 17 groups of central composite experiments were designed for the three factors at three levels: the mixing amount of gasification slag in …

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Comprehensive Recycling Utilization Technology Of Foundation Engineering Slurry, Xie Hui, Ye Jingliang, Chen Juan, Xue Man, Hu Huicong, Yang Xianyu, Cai Jihua Dec 2022

Comprehensive Recycling Utilization Technology Of Foundation Engineering Slurry, Xie Hui, Ye Jingliang, Chen Juan, Xue Man, Hu Huicong, Yang Xianyu, Cai Jihua

Coal Geology & Exploration

Foundation engineering slurry in the fields of underground continuous walls, horizontal directional drilling, shield, and pipe jacking has the characteristics of large amount of consumption and relatively single pollutant. With the implementation of various national environmental protection laws and regulations, the comprehensive treatment of slurries is particularly important. In this paper, a set of comprehensive recycling utilization technology of foundation engineering slurry was proposed. The technology of sand removal plus recycling of purified slurry and drilling cuttings can be adopted to the circulating slurry, and the technology of calcium removing, pH reducing, flocculation separation, pressure filtration and recycling of wastewater …

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The Sexual And Gender-Based Violence Epidemic Meets The Covid-19 Pandemic: Survivors’ And Advocates’ Narratives In Egypt, Mozn Hassan, Helen Rizzo Dec 2022

The Sexual And Gender-Based Violence Epidemic Meets The Covid-19 Pandemic: Survivors’ And Advocates’ Narratives In Egypt, Mozn Hassan, Helen Rizzo

Faculty Journal Articles

This research traces activism over the last 30 years against sexual and gender-based violence with a focus on survivors’ and advocates’ narratives in Egypt. We argue that several focusing events in Egypt and the support of transnational advocacy networks over the last decades have galvanised the efforts of activists and citizens of good will to mobilise around these issues. Egyptian feminist mobilisation during the pandemic brought to the public sphere the untold stories of the forms of violence that occurred through online and social media platforms. While social media and other online tools hold the promise of becoming “a new …

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Geochemical Characteristics And Sedimentary Model Of Shales In Lower Member Of Zhongjiangou Formation In Wudun Sag, Dunhuang Basin, Deng Wei, Yang Tao, Fan Shenglong, Liu Zirui, Wan Xuhui, Xiao Juanyi, Cao Taotao Dec 2022

Geochemical Characteristics And Sedimentary Model Of Shales In Lower Member Of Zhongjiangou Formation In Wudun Sag, Dunhuang Basin, Deng Wei, Yang Tao, Fan Shenglong, Liu Zirui, Wan Xuhui, Xiao Juanyi, Cao Taotao

Coal Geology & Exploration

Analysis on the sedimentary environment of shale is of great significance for the evaluation of shale gas reservoir and the optimization of sweet spot. In order to deeply explore the depositional environment of organic-rich shale and the mechanism of organic matter accumulation in the Lower member of Zhongjiangou Formation of Wudun Sag in Dunhuang Basin, the TOC content, maceral composition, carbon isotope, major elements, trace elements and rare earth element were tested based on DY1 well. The results indicate that the lithologies of the Lower member of Zhongjiangou Formation in Wudun Sag are gray-black carbonaceous shale and silty shale with …

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Chemistry Doctoral Graduate Named Finalist For Prestigious Award, Gaye Swan Dec 2022

Chemistry Doctoral Graduate Named Finalist For Prestigious Award, Gaye Swan

University of Mississippi News

Leigh Anna Hunt honored at national graduate student awards symposium

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Application Of Artificial Intelligence To Lithium-Ion Battery Research And Development, Zhen-Wei Zhu, Jing-Yi Qiu, Li Wang, Gao-Ping Cao, Xiang-Ming He, Jing Wang, Hao Zhang Dec 2022

Application Of Artificial Intelligence To Lithium-Ion Battery Research And Development, Zhen-Wei Zhu, Jing-Yi Qiu, Li Wang, Gao-Ping Cao, Xiang-Ming He, Jing Wang, Hao Zhang

Journal of Electrochemistry

Lithium-ion batteries (LIBs) have become one of the best solutions to the energy storage issue in modern society. However, the battery materials and device development are both complex, and involve multivariable problems. Traditional trial-and-error approach, which relies on researchers to conduct experiments, has encountered bottlenecks in the improvement of the battery performance. Artificial intelligence (AI) is the most potential technology to deal with this issue due to its powerful high-speed and capabilities of processing massive data. In particular, the capability of machine learning (ML) algorithms in assessing multidimensional data variables and discovering patterns in the sets are expected to assist …

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Multi-Electron Reaction-Boosted High Energy Density Batteries: Material And System Innovation, Rui-Qi Guo, Feng Wu, Xin-Ran Wang, Ying Bai, Chuan Wu Dec 2022

Multi-Electron Reaction-Boosted High Energy Density Batteries: Material And System Innovation, Rui-Qi Guo, Feng Wu, Xin-Ran Wang, Ying Bai, Chuan Wu

Journal of Electrochemistry

The continuous development of the global energy structure transformation has put forward higher demands upon the development of batteries. The improvements of the energy density have become one of the important indicators and hot topic for novel secondary batteries. The energy density of existing lithium-ion battery has encountered a bottleneck due to the limitations of material and systems. Herein, this paper introduces the concept and development of multi-electron reaction materials over the past twenty years. Guided by the multi-electron reaction, light weight electrode and multi-ion effect, current development strategies and future trends of high-energy-density batteries are highlighted from the perspective …

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Psychological Well-Being And Student Academic Burnout, Henny Indreswari, Devy Probowati, Indriyana Rachmawati Dec 2022

Psychological Well-Being And Student Academic Burnout, Henny Indreswari, Devy Probowati, Indriyana Rachmawati

Jurnal Kajian Bimbingan dan Konseling

Psychological well-being is an important aspect for students that needs to be considered in the current situation, which in fact many are faced with academic burnout. This research was conducted with the aim of knowing the relationship between psychological well-being and student academic burnout. The research design used is correlation, with a research sample of 180 students. The sampling technique used is proportional random sampling. Collecting data using psychological well-being scale and academic burnout scale. The data analysis technique used is Pearson's product moment. The results showed that psychological well-being has a negative relationship with academic burnout. This means that …

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Students' Engagement Model In Online Learning Guided By School Counselor During Covid-19 Pandemic, Iis Solihah, Budi Astuti, Mussa Saidi Abubakari Dec 2022

Students' Engagement Model In Online Learning Guided By School Counselor During Covid-19 Pandemic, Iis Solihah, Budi Astuti, Mussa Saidi Abubakari

Jurnal Kajian Bimbingan dan Konseling

The transformation into online learning during Covid 19 pandemic induces culture shock for students, teachers, and parents. Consequently, students present less participation in online learning. One of the stakeholders capable of improving students’ learning engagement is the school counselor. This study aims to examine secondary school students’ learning involved in the guidance and counseling online program. In this study, we employed a descriptive-quantitative research method, then collected data using a survey method and questionnaire. As many as 293 secondary school students from Java, Indonesia, participated in this study. Further, the obtained data were analyzed using SmartPLS 3. Our analysis results …

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Notes From The Editor, Jay Nathan Dec 2022

Notes From The Editor, Jay Nathan

Journal of Global Awareness

No abstract provided.

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What Makes Classroom Observation Feedback Useful? The Perceptions Of Secondary Math And English Teachers, Amanda Frasier Dec 2022

What Makes Classroom Observation Feedback Useful? The Perceptions Of Secondary Math And English Teachers, Amanda Frasier

ETSU Faculty Works

Teachers (n=14) at four high schools in North Carolina were interviewed about their perspectives of evaluation policy at two time points during the 2016-2017 school year. This study specifically examined statements teachers made about feedback from observations using de-identified interview transcripts. Teachers discussed feedback from formal observations along with other sources of informal observational feedback (e.g., coaches, peers). Overall, teachers described useful feedback as that which provided actionable recommendations informed by the observer’s knowledge of three domains: the classroom context (as aided by the frequency and timing of observations), subject area, and pedagogy. Teachers also identified two aspects of formal …

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Advances On Composite Cathodes For Lithium-Sulfur Batteries, Xi-Yao Li, Chang-Xin Zhao, Bo-Quan Li, Jia-Qi Huang, Qiang Zhang Dec 2022

Advances On Composite Cathodes For Lithium-Sulfur Batteries, Xi-Yao Li, Chang-Xin Zhao, Bo-Quan Li, Jia-Qi Huang, Qiang Zhang

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries are deemed as high-promising next-generation energy storage technique due to their ultrahigh theoretical energy density, where the sulfur cathodes with high specific capacity guarantee the energy density advantage and directly determine the battery performances. After decades of exploration, the most promising sulfur cathodes are sulfur/carbon composite (S/C) cathodes and sulfurized polyacrylonitrile (SPAN) cathodes. In this manuscript, recent advances on S/C and SPAN cathodes in Li-S batteries are comprehensively reviewed. The electrochemical reaction circumstances on S/C and SPAN cathodes are firstly introduced and compared to reveal the working mechanisms of the two types of Li-S batteries. The S/C …

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Carbon-Al Interface Effect On The Performance Of Ionic Liquid-Based Supercapacitor At 3 V And 65 OC, Zhen-Zhen Ye, Shu-Ting Zhang, Xin-Qi Chen, Jin Wang, Ying Jin, Chao-Jie Cui, Lei Zhang, Lu-Ming Qian, Gang Zhang, Wei-Zhong Qian Dec 2022

Carbon-Al Interface Effect On The Performance Of Ionic Liquid-Based Supercapacitor At 3 V And 65 OC, Zhen-Zhen Ye, Shu-Ting Zhang, Xin-Qi Chen, Jin Wang, Ying Jin, Chao-Jie Cui, Lei Zhang, Lu-Ming Qian, Gang Zhang, Wei-Zhong Qian

Journal of Electrochemistry

Ionic liquid (IL) electrolyte-based supercapacitors (SCs) have advantages of high operating voltage window, high energy density and nonflammability, as compared to conventional acetonitrile-based organic electrolyte SCs, and are typically suitable for the large-scale energy storage in the era of carbon neutrality full of renewable, but unstable electricity. However, current efforts were concentrated on the study with coin-cell type of IL-SCs, and less has been reported on the pouch type of IL-SCs for a long cycling time yet. To fabricate a reliable SC for the life time test or for the accelerated aging test under high temperature, one should concern the …

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Preparation Of Highly-Cyclized Sulfurized Polyacrylonitrile For Lithium-Sulfur Batteries, Xuan Ji, Jia-Yu Wang, An-Bang Wang, Wei-Kun Wang, Ming Yao, Ya-Qin Huang Dec 2022

Preparation Of Highly-Cyclized Sulfurized Polyacrylonitrile For Lithium-Sulfur Batteries, Xuan Ji, Jia-Yu Wang, An-Bang Wang, Wei-Kun Wang, Ming Yao, Ya-Qin Huang

Journal of Electrochemistry

Sulfurized polyacrylonitrile (SPAN) is regarded as an attractive cathode candidate of lithium-sulfur (Li-S) batteries for its non-dissolution mechanism and effective alleviation of polysulfides shuttling issue in Li-S batteries, displaying high utilization of cathode active material, outstanding cycle stability and structural stability. However, the relation between cyclization degree and cycle stability of SPAN is still unveiled. In this work, SPAN-C-V composites were synthesized by co-introduction of CuSO4 and zinc n-ethyl-n-phenyldithiocarbamate (ZDB) in the co-heating of sulfur and polyacrylonitrile. The co-introduction of CuSO4 and ZDB reduced the cyclization reaction onset temperature of PAN while increased the C—C/C=C within SPAN-C-V, thus …

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Experimental Study On High-Pressure Hydraulic Percussive Rotary Drilling Based On Single-Tooth Rock-Breaking Process, Dou Xuqian, Yao Ningping, Li Xiushan, Wang Li, Zhang Kai, Wei Hongchao Dec 2022

Experimental Study On High-Pressure Hydraulic Percussive Rotary Drilling Based On Single-Tooth Rock-Breaking Process, Dou Xuqian, Yao Ningping, Li Xiushan, Wang Li, Zhang Kai, Wei Hongchao

Coal Geology & Exploration

Aiming at the problem of low efficiency of hard rock drilling in crossing borehole in underground coal mine, the morphology of crushing pit formed by column tooth under the percussive load was analyzed based on the percussive rotary drilling mechanism and the main characteristics of Wassara high-pressure hydraulic impactor, and the crushing pit was divided into the four areas of disintegration area, compact area, crack area and elastic area. On this basis, process analysis was performed on the continuous tooth rock-breaking with large and small interval impact. Meanwhile, the technical parameters of high-pressure hydraulic percussive rotary drilling were discussed with …

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Precise Magnetotelluric Single-Component Processing Technology And Detection Of Deep Disaster-Causing Water Body, Li Peitao, Wu Qiang, Li Zhuorong, Li Wenyu, Xie Jian, Wang Yuxi Dec 2022

Precise Magnetotelluric Single-Component Processing Technology And Detection Of Deep Disaster-Causing Water Body, Li Peitao, Wu Qiang, Li Zhuorong, Li Wenyu, Xie Jian, Wang Yuxi

Coal Geology & Exploration

In order to realize the fine detection of hydrogeological conditions by natural source single-component magnetotelluric technology, the problems of magnetotelluric signal acquisition and processing were systematically analyzed, and study was conducted for the response characteristics of underground water-rich area on magnetotelluric wave. Besides, water-richness index model was established according to the magnetotelluric sounding theory and analytic hierarchy process. Moreover, the corresponding relationship between waveform and lithology was fitted based on a large amount of experimental data, and the information on physical properties, such as the dielectric constant, elastic brittleness, density and porosity was extracted from the fractal dimension of waveform. …

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