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International Journal of Mining Science and Technology 2022年第4期32卷 761-777页

作者： lan qiao Jiawang Hao Zhiyi Liu Qingwen Li Naifu Deng Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China School of Mining Engineering North China University of Science and TechnologyTangshan 063210China

The surrounding rock in tunnelling engineering and coal mining will sometimes be exposed to high temperature. Rock failure is the result of energy dissipation, and the study of the evolution and transformation behavior of energy is of great significance for the in-depth understanding of the deformation and failure of rock after high temperature. This study analyzed the intrinsic connection between mechanical properties and acoustic emission(AE) energy under temperature effect. Based on the energy dissipation and release theory, the distribution and transformation of energy was analyzed, and the energy selfincentive and self-inhibition(EII) model was further established. The main findings are that temperature effect affects the confidence interval trend and the value of AE energy rate, which is related to the change in mechanical properties. The ability of sandstone to store elastic strain energy after exposure to high temperature is independent of the mechanical properties. In this study, the ratio of dissipated energy to elastic energy is used to characterize the stable state of the sandstone system, which can be used as the energy indicator of rock failure precursor. During the absorption, storage, and release of energy before the peak stress, there exists self-incentive and self-inhibition of energy(control behavior).

关键词： Exposure to high temperature Rock failure Energy behavior Energy indicator Self-control of energy

Thieno[3,4-c]pyrrole-4,6-dione based copolymers for high performance organic solar cells and organic field effect transistors

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Chinese Chemical Letters 2016年第8期27卷 1277-1282页

作者： Pan He Xiao-lan qiao Qun Qian Hong-Xiang Li Department of Chemistry Shanghai University Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Donor-acceptor type copolymers have wide applications in organic field-effect transistors and organic photovoltaic ***[3,4-c]pyrrole-4,6-dione（TPD）,as an electron-withdrawing unit,has been widely used in D-A type copolymers *** now,the highest power conversion efficiency and mobility of TPD-based copolymers are over 8% and 1.0 cm^2 V^（-1） s^（-1） *** this review,the recent progress of TPD-based copolymers in organic solar cells and organic transistors is summarized.

关键词： Donor-acceptor type copolymers Organic semiconductors Thieno[3 4-c]pyrrole- 6-dione unit Organic transistors Organic solar cells

Synergistic Effects of Solvent Vapor Assisted Spin-coating and Thermal Annealing on Enhancing the Carrier Mobility of Poly(3-hexylthiophene)Field-effect Transistors

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Chinese Journal of Polymer Science 2021年第7期39卷 849-855页

作者： Xiao-lan qiao Jie Yang Lian-He Han Ji-Dong Zhang Mei-Fang Zhua State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Poly(3-hexylthiophene)(P3HT)thin films,obtained by normal spin-coating and solvent vapor assisted spin-coating(SVASP)before and after thermal annealing(TA),and the corresponding devices were prepared to unravel the microstructure-property relationship,which is of great importance for the development of organic *** SVASP-TA films were used as the active layers of the organic field-effect transistors,a hole mobility up to 0.38 cm^(2)·V^(-1)·s^(-1)was *** mobility was one of the highest values and one order of magnitude higher than that of the normal spin-coating films based *** relationship between the microstructure and the device performance was fully investigated by UV-Vis absorption spectra,grazing incident X-ray diffraction(GIXD),and atomic force microscopy(AFM).The impressive mobility was attributed to the high crystallinity and ordered molecule packing,which stem from the synergistic effects of SVASP and thermal annealing.

关键词： Poly(3-hexylthiophene) Polymer field-effect transistors Microstructure Polymer semiconductors

What Is Semantic Communication?A View on Conveying Meaning in the Era of Machine Intelligence

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Journal of Communications and Information Networks 2021年第4期6卷 336-371页

作者： qiao lan Dingzhu Wen Zezhong Zhang Qunsong Zeng Xu Chen Petar Popovski Kaibin Huang Department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999007China Department of Electronic Systems Aalborg UniversityAalborgDenmark

In the 1940s,Claude Shannon developed the information theory focusing on quantifying the maximum data rate that can be supported by a communication *** by this fundamental work,the main theme of wireless system design up until the fifth generation(5G)was the data rate *** Shannon’s theory,the semantic aspect and meaning of messages were treated as largely irrelevant to *** classic theory started to reveal its limitations in the modern era of machine intelligence,consisting of the synergy between Internet-of-things(IoT)and artificial intelligence(AI).By broadening the scope of the classic communication-theoretic framework,in this article,we present a view of semantic communication(SemCom)and conveying meaning through the communication *** address three communication modalities:human-to-human(H2H),human-to-machine(H2M),and machine-to-machine(M2M)*** latter two represent the paradigm shift in communication and computing,and define the main theme of this article.H2M SemCom refers to semantic techniques for conveying meanings understandable not only by humans but also by machines so that they can have interaction and“dialogue”.On the other hand,M2M SemCom refers to effective techniques for efficiently connecting multiple machines such that they can effectively execute a specific computation task in a wireless *** first part of this article focuses on introducing the SemCom principles including encoding,layered system architecture,and two design approaches:1)layer-coupling design;and 2)end-to-end design using a neural *** second part focuses on the discussion of specific techniques for different application areas of H2M SemCom[including human and AI symbiosis,recommendation,human sensing and care,and virtual reality(VR)/augmented reality(AR)]and M2M SemCom(including distributed learning,split inference,distributed consensus,and machine-vision cameras).Finally,we discuss the approach for designing S

关键词： semantic communication artificial intelligence Internet-of-things

Field Investigation and FEM Analysis of Ground Subsidence in a Chinese Underground Gold Mine

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 1-4页

作者： Meifeng Cai lan qiao Bo Yu ChanghongLi Resources Engineering School, University of Science and Technology Beijing, Beijing 100083 Resources Engineering School University of Science and Technology Beijing Beijing 100083 China

Ground subsidence in a Chinese underground gold mine is remarkable. To find out reasons and regularities of the subsidence, following research work was carried out: (1) systemetical investigations of engineering geological conditions, including in situ stress sta- te, locstion and size of old river beds, ponds and unfilled mined-out areas, (2) in situ monitoring of strata movement by multi-point ex tensometers in 3 vertical boreholes; (3) FEM (Finite Element Method) analysis to study the relationship between the ground subsidence and mining excavation, especially to inspect the influence of unfilled mined-out areas at shallow depth on the subsidence. Based on the research results, measures to control the ground subsidence and to prevent buildings from damage are provided.

关键词： ground subsidence mining excavation regularities influencing factors, control measures.

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He Han Ling-Wei Kong Li-Ping Zhu Xiao-lan qiao Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

Study of viruses co-infecting white clover(Trifolium repens)in China

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Journal of Integrative Agriculture 2017年第9期16卷 1990-1998页

作者： LIANG qiao-lan WEI Lie-xin XU Bing-liang A.Calderón-Urrea XIANG Dong College of Plant Protection Gansu Agricultural UniversityLanzhou 730070P.R.China Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province Lanzhou 730070P.R.China Department of Biology California State UniversityFresnoCA 93740USA

Globally, white clover（Trifolium repens L.） is commonly infected by plant viruses. It is grown at gardens, roadsides, and public areas as ornamental plants in northern China. Some leaves present disease symptoms that are similar to those of virus infection. However, to our knowledge, no records are available from China regarding white clover（Trifolium repens L.） virus co-infection. To determine the viral species that infect white clover in China, plant samples with virus disease symptoms were collected and virion morphology and ultrastructure morphology of co-infected plants were observed by electron microscopy; viruses were detected by enzyme linked immunosorbent assay（ELISA） and reverse transcription PCR（RT-PCR）. Virus co-infection was studied by double antibody sandwich enzyme linked immunosorbent assay（DAS-ELISA） and real-time fluorescence quantitative PCR（RT-q PCR） after rub-inoculation of virus-free white clover planted in a growth chamber（25°C） with a photoperiod of 16 h, using single or several purified virions. Results showed that there were six types of symptoms, including those of shrinking mosaic, shrinking and macular mosaic, severe mottle mosaic, yellow macular mosaic, shrinkage chlorisis, and ring plaque and ring stria. The incidence rates for each symptom were 20.93, 1.48, 16.85, 59.07, 1.30, and 0.37%, respectively, based on the field investigation. Two types of viral pathogens were identified as Alfalfa mosaic virus（AMV） and White clover mosaic virus（WCMV）. In mesophyll cells, virus particles with bacilliform virions formed aggregates and linear virions were bundle shaped. The detection rate of AMV was 100% in white clover samples by DAS-ELISA and RT-PCR detection, whereas that of WCMV was 83.33%. The co-infection rate was 83.33%. The relative contents of AMV and WCMV were significantly increased by 5.897-and 3.515-fold upon co-infection, when compared to that with single virus infection. We observed larger starch particles and fewer or collapsed c

关键词： clover AMV WCMV viral co-infection virus-induced pathological changes DAS-ELISA RT-PCR RT-qPCR

Stress Measurement with an Improved Hollow Inclusion Technique In Jinchuan Nickel Mine

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 157-160页

作者： Meifeng Cai, lan qiao, Bo Yu, Shuanghong Wang (Resources Engineering School, University of Science and Technology Beijing, Beijing 100083) Resources Engineering School University of Science and Technology Beijing Beijing 100083 China

Borehole overcoring stress measurement with an improved hollow inclusion technique was carried out at 10 points on 3 levels in Jinchuan nickel mine which is situated in north-west of China. Through the measurement, 3-D in situ stress state at the measuring points and distribution characteristics of the stress field in the mine were obtained. The stress state in Jinchuan mine is dominated by the horizontal tectonic stress field. The maximum principal stress is horizontal which is about twice the weight of the overburden and its orientation is approximately vertical to the regional tectonic line. The difference between two horizontal principal stresses is quite large which is an important reason to cause failure of underground excavations.

关键词： stress measurement overcoring technique hollow inclusion cell improvement Jinchuan nickel mine

Feasibility Study on Continuous Mining Method in Deep Position of Jinchuan Nickel Mine, China

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Journal of University of Science and Technology Beijing 2001年第2期8卷 81-85页

作者： Meifeng Cai, lan qiao, Changhong Li, Shuanghong Wang (Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083, China) Univ Sci & Technol Beijing Civil & Environm Engn Sch Beijing 100083 Peoples R China

Jinchuan nickel mine is the largest nickel mine in China. Cut-and-fill mining method with high density cementing materials is used in the mine. The original mining design divided the mining operation into two steps. The first step stopped the mining rooms and the second step stopped the pillars. Because the two-step method made big trouble for finally mining pillars and strongly limited the mining speed and production, it was successfully changed to a continuous cut-and-fill method without pillars. However, the mining operation in the mine has been down to 800 m and the mining condition is getting worse and more complicated. Through systematical field investigations and 3-D FEM analysis, it is proved that the mining method without pillars is feasible for mining deeper orebodies in Jinchuan nickel mine.

关键词： Jinchuan nickel mine deep position continuous mining feasibility study

新城金矿深部采场结构参数和开采顺序优化研究

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金属矿山 2001年第6期30卷 11-15页

作者：乔兰北京科技大学

采用有限元数值模拟计算方法 ,对新城金矿深部采场的 4种结构参数和 2种开采顺序等 6个方案进行了不同开采时期的优化分析和比较 ,获得了深部采场的最佳结构参数。研究中采用“品”字形连续开采的工作面布置方式可形成免压拱效应。

关键词：采矿方法采场结构参数开采顺序金矿深部采场