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Journal of Energy Chemistry 2021年第10期30卷 574-581,I0015页

作者： Qi-Qi Qiu shan-shan Yuan Jian Bao Qin-chao Wang Xin-Yang Yue Xun-Lu Li Xiao-Jing Wu Yong-Ning Zhou Department of Materials Science Fudan UniversityShanghai 200433China

Ni-rich layered oxide LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(x≥0.8)is the most promising cathodes for future high energy automotive lithium-ion ***,its application is hindered by the undesirable cycle stability,mainly due to the irreversible structure change at high ***,we demonstrate that F substitution with the appropriate amount(1 at%)is capable for improve the electrochemical performance of LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cathode *** is revealed that F substitution can reduce cation mixing,stabilize the crystal structure and improve Li transport *** resulted LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(1.99)F_(0.01)cathode can deliver a high capacity of 194.4 mAh g^(-1) with capacity retention of 95.5%after 100 cycles at 2 C and 165.2 mAh g^(-1) at 5 ***-situ synchrotron X-ray technique proves that F ions in the cathode materials can suppress the irreversible phase transition from H2 phase to H3 phase in high voltage region by preventing oxygen gliding in a-b planes,ensuring a long-term cycle stability.

关键词： Lithium batteries Cathode materials Nickel-rich Phase transition Fluorine substitution

Mixture of Electromagnetically Induced Transparency and Autler–Townes Splitting in a Five-Level Atomic System

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Communications in Theoretical Physics 2017年第2期67卷 217-221页

作者： Xiao-Yun Zhang shan Wu Hai-chao Li College of Physics and Electronic Science Hubei Normal University Huangshi 435002 China Institute for Interdisciplinary Research Jianghan University Wuhan 430056 China College of Science China Three Gorges University Yichang 443002 China

Discerning electromagnetically induced transparency(EIT) from Autler–Townes splitting(ATS) is a significant issue in quantum optics and has attracted wide attention in various three-level configurations. Here we present a detailed study of EIT and ATS in a five-level atomic system considered to be composed of a four-level Y-type subsystem and a three-level Λ-type subsystem. In our theoretical calculations with standard density matrix formalism and steadystate approximation, we obtain the general analytical expression of the first-order matrix element responsible for the probe-field absorption. In light of the well-known three-level EIT and ATS criteria, we numerically show an intersection of EIT with ATS for the Y-type subsystem. Furthermore, we show that an EIT dip is sandwiched between two ATS dips(i.e., multi-dip mixture of EIT and ATS) in the absorption line for the five-level system, which can be explained by the dressed-state theory and Fano interference.

关键词： electromagnetically induced transparency Autler–Townes splitting five-level atomic systems

Microstructure evolution and mechanical properties of high-boron steel with different ratios of boron and carbon

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China Foundry 2022年第2期19卷 169-176页

作者： Ming-chen Ma chao-qing Luo Si-min Chen Hong-qun Tang shan-shan Hu Yu-mei Zhou Jian-lin Liang Guangxi Key Laboratory of Processing for Nonferrous Metals and Featured Materials Center of Ecological Collaborative Innovation for Aluminium Industry in GuangxiSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China School of Mechanical Engineering Guangxi UniversityNanning 530004China School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou 510665China

Boron and carbon contents are the main factors influencing the properties of high-boron *** this study,experimental samples with different boron-to-carbon ratios(%B/%C)were *** microstructures of the different samples were observed,and their hardness,bending strength,and impact toughness were *** show that the main microstructures in the investigated high-boron steel samples are the eutectic Fe_(2)B structure with a fishbone shape and the ternary peritectic Fe_(3)(C,B)structure with a chrysanthemum *** the boron content is 2.5wt.%and the carbon content is 0.43wt.%(i.e.,%B/%C=5.82),the overall mechanical properties of the alloy are the *** alloy's hardness,bending strength and impact toughness reach their maximums,which are 67.3 HRC,1,267.36 MPa and 6.19 J·cm^(-2),*** optimized alloy is compared with conventional materials exhibiting excellent wear resistance(namely,high-manganese steel and high-chromium cast iron)through two-body and three-body abrasion *** wear resistance of this high-boron steelinvestigated in this work is found to be superior to those of the more common materials.

关键词： high-boron steel boron and carbon contents wear resistance microstructure mechanical properties

Dehydration-triggered structural phase transition-associated ferroelectricity in a hybrid perovskite-type crystal

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Chinese Chemical Letters 2024年第10期35卷 461-464页

作者： Zhi-Yuan Yue Hua-Kai Li Na Wang shan-shan Liu Le-Ping Miao Heng-Yun Ye chao Shi chaotic Matter Science Research Center Jiangxi University of Science and TechnologyGanzhou 341000China

Since the appearance of Rochelle salt,ferroelectrics have received extensive attention from researchers due to they are playing an important role in sensors,memories,mechanical actuation,and so *** recent years,with the rapid development of molecular ferroelectrics,high-performance molecular ferroelectrics have become effective complement to inorganic ***,compared with inorganic ferroelectrics,the family of molecular ferroelectrics is relatively scarce,and exploring highperformance ferroelectric materials through new synthesis strategies has become the trend of molecular ***,we successfully transformed non-polar material 1(2-H_(2)PCA)_(2)(H_(2)O)CdCl_(6)(2-H_(2)PCA=2-picolylamine cation)into polar material 2(2-H_(2)PCA)2CdCl_(6)by single-crystal to single-crystal transformation(SCSCT).Meanwhile,2 exhibits clear ferroelectricity with a high-temperature Tc of 378 K,a Ps of 1.18μC/cm^(2)at 300 *** work not only realizes the purpose of synthesizing ferroelectrics by forming polar structures by SCSCT,but also realizes the reversibility of SCSCT,which provides ideas for the construction and exploration of new molecular ferroelectrics.

关键词： Hybrid perovskite Ferroelectric materials Single-crystal to single-crystal transformation Phase transition Stimulus-structure-response

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-Bin Liu Shen Huang Ding-chao tian Lai-Min Shi shan-Bi Peng He Zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD

Ductile Fracture Prediction of 316LN Stainless Steel in Hot Deformation Process

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Journal of Iron and Steel Research International 2014年第10期21卷 923-930页

作者： Jian-li HE Juan LIU Zhen-shan CUI chao-zhong YANG Fei CHEN School of Materials Engineering Shanghai University of Engineering Science National Engineering Research Center for Die and Mold CAD School of Materials Science and EngineeringShanghai Jiao Tong University

A ductile fracture criterion of 316LN stainless steel, combined with the plastic deformation capacity of ma- terial and the stress state dependent damages, was proposed to predict ductile fracture during hot deformation. To the end, tensile tests at high temperatures were first performed to investigate the fracture behavior of 316LN stain- less steel. The experimental results show the variation of the critical fracture strain as a function of temperature and strain rate. Second, the criterion was calibrated by using the upsetting tests and the corresponding numerical simula- tions. Finally, the proposed fracture criterion was validated by the designed tests and the corresponding finite ele- ment （FE） simulation. The results show that the criterion can successfully predict the onset of ductile fracture at ele- vated temperatures.

关键词： ductile fracture criterion FE simulation upsetting test fracture behavior 316LN stainless steel

Regulatory RNAs,microRNA,long-non coding RNA and circular RNA roles in colorectal cancer stem cells

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World Journal of Gastrointestinal Oncology 2022年第4期14卷 748-764页

作者： Hsiao-Mei chao Teh-Wei Wang Edward Chern shan-hui Hsu Department of Pathology Wan Fang HospitalTaipei Medical UniversityTaipei 11696Taiwan Department of Pathology School of MedicineCollege of MedicineTaipei Medical UniversityTaipei 110Taiwan niChe Lab for Stem Cell and Regenerative Medicine Department of Biochemical Science and TechnologyNational Taiwan UniversityTaipei 10617Taiwan Institute of Polymer Science and Engineering National Taiwan UniversityTaipei 10617Taiwan

The properties of cancer stem cells(CSCs),such as self-renewal,drug resistance,and metastasis,have been indicated to be responsible for the poor prognosis of patients with colon *** epigenetic regulatory network plays a crucial role in CSC *** non-coding RNA(ncRNA),including microRNAs,long noncoding RNAs,and circular RNAs,have an important influence on cell *** modulate cells by regulating gene expression in different *** review discusses the basic characteristics and the physiological functions of colorectal cancer(CRC)stem *** of these ncRNAs will help us understand the pathological mechanism of CRC progression,and they could become a new target for cancer treatment.

关键词： Regulatory RNAs MicroRNA Long-non coding RNA Circular RNA Colorectal cancer Cancer stem cell Stemness

Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling

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Petroleum Science 2024年第2期21卷 741-751页

作者： Shuang-Biao Han chao-Han Xiang Xin Du Lin-Feng Xie Jie Huang Cheng-shan Wang College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China

The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen *** gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been *** on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different *** gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary *** increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to *** origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and *** shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic ***,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived *** discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.

关键词： Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin

从教学技能掌握到教学素养发展:新时代好教师的核心追求

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黑龙江高教研究 2025年第1期43卷 22-30页

作者：单妍李志厚广东药科大学广东广州510006 广州华商学院广东广州511300 华南师范大学广东广州510631

教学素养是教育者经过专业学习和课堂教学实践培养和磨炼之后所表现出来的专业化教学素质与涵养,是教师专业所特有的内在素质和外在表现。它与教学技能、教学能力不同,在其基础上还包括教育信念、专业知能、教学眼光、通化意识、教育思... 详细信息

教学素养是教育者经过专业学习和课堂教学实践培养和磨炼之后所表现出来的专业化教学素质与涵养,是教师专业所特有的内在素质和外在表现。它与教学技能、教学能力不同,在其基础上还包括教育信念、专业知能、教学眼光、通化意识、教育思维、创新追求以及教育家精神等方面的素养。通过对教学素养与教学技能、教学能力异同的比较分析,探讨教育者教学素养发展的影响因素、形成条件、发展机制及其相关的问题,为有效促进新时代教师教学素养的发展以及新质教育力的探索提供有力参考。

关键词：教学技能教学能力教学素养教学创新新质教育力通化意识

Near-Threshold Wide-Voltage Design Review

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Tsinghua Science and Technology 2023年第4期28卷 696-718页

作者： Yan Zhao Jun Yang chao Chen Weiwei shan Peng Cao Yongliang Zhou Ziyu Li Tai Yang National Application Specific Integrated Circuit(ASIC)Center Southeast UniversityNanjing 210096China

This paper presents a comprehensive review of near-threshold wide-voltage designs on memory,resilient logic designs,low voltage Radio Frequency(RF)circuits,and timing *** the prosperous development of wearable applications,low power consumption has become one of the primary challenges for IC *** improve the power efficiency,the prefer scheme is to operate at an ultra low voltage of Near Threshold Voltage(NTV).For the performance variation and degradation,a self-adaptive margin assignment technique is proposed in the low *** proposed technique tracks the circuit states in real time and dynamically allocates voltage margins,reducing the minimum supply voltage and achieving higher energy *** self-adaptive margin assignment technique can be used in Static Random Access Memory(SRAM),digital circuits,and analog/RF *** on the self-adaptive margin assignment technique,the minimum voltage in the 40 nm CMOS process is reduced to 0.6 V or even lower,and the energy efficiency is increased by 3–4 times.

关键词： Near Threshold Voltage(NTV) wide-voltage memory resilient logic design low voltage Radio Frequency(RF) timing analysis