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The trapping effect of sulfur sensitization center Ag_2S cluster on T-grain AgBrI microcrystals

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 744-751页

作者： YANG Shaopeng fu guangsheng LI Xiaowei TIAN Xiaodong College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China College of Physics Science and Technology Hebei University Baoding 071002 China

The microwave absorption dielectric-spectrum technique was used to study the decay kinetics of photoelectrons in sulfur-sensitized silver halide crystals. The time-resolution spectrum of free electrons and shallow-trapped electrons generated in sulfur-sensitized AgBrl crystals has been obtained. The relationship of the trapping effect of sensitization centers Ag2S and sensitization time or temperature in emulsions has been duscussed. With the increase in the sensitization time and temperature, the trap effect of sulfur sensitization centers varies from hole trap to shallow electron trap, and deep electron trap.

关键词： silver halide, sulfur-sensitized, photoelectron, trapping effect, microwave absorption dielectric-spectrum.

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损伤岩石声发射演化特征及响应机制试验研究

煤田地质与勘探 2024年第3期52卷 96-106页

作者：张凯张东晓赵勇强杨英明郭伟耀孙鹏胥林鹏付光胜北京低碳清洁能源研究院煤炭开采水资源保护与利用全国重点实验室北京102211 国家能源投资集团有限责任公司北京100011 山东科技大学能源与矿业工程学院山东青岛266590 中国冶金地质总局青岛地质勘查院山东青岛266590

岩石内部损伤演化是导致岩土工程灾害的原因之一,揭示岩石破裂过程中的关键参数响应特征可为岩石破坏后失稳状态识别提供依据,对于岩体工程灾害预警防控至关重要。通过循环加载-卸载(加卸载)试验制备不同损伤程度粉砂岩试样,利用损伤试... 详细信息

岩石内部损伤演化是导致岩土工程灾害的原因之一,揭示岩石破裂过程中的关键参数响应特征可为岩石破坏后失稳状态识别提供依据,对于岩体工程灾害预警防控至关重要。通过循环加载-卸载(加卸载)试验制备不同损伤程度粉砂岩试样,利用损伤试样开展单轴加载试验,分析试样损伤程度与波速关系及声发射演化规律,探讨不同损伤程度岩石的声发射响应机制。结果表明:(1)损伤试样纵波波速随着损伤程度增加呈线性减小趋势,但声发射振铃计数由阶段性递增转变为加载全过程迅速增加,声发射能量在屈服阶段由小幅度突增转变为快速增加。(2)反映岩石内部不同尺度裂隙发展趋势的声发射b值峰值区由峰后破坏阶段向压密阶段转移,造成峰后破坏阶段失稳特征不明显,反映岩体内部声发射源集中程度和能量尺度的S值在压密至屈服阶段由低位中幅度波动转变为高位小幅度波动,表明岩石在峰前阶段产生非稳定破坏。(3)损伤试样破裂过程随着损伤程度增加由晶间滑移主导型转变为裂隙发育主导型,导致声发射高频低能(400~800 kHz、0~250 aJ)信号由零星出现转变为加载全过程密集分布,以及高频信号带变宽。(4)损伤岩石内部裂隙发育程度不同是导致声发射响应机制差异化的根本原因,岩石内部裂隙密度随着损伤程度增加而增大,造成其在受载过程中由渐进式稳定破坏模式向突发式非稳定破坏模式转变,同时加载过程中声发射信号活跃度及强度增强。研究获得了不同损伤程度岩石的声发射参数特征,可为工程岩体损伤程度识别提供理论依据。

关键词：损伤岩石波速声发射能量主频响应机制

近距离薄煤层群首采层卸压瓦斯协同抽采技术研究

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中国安全生产科学技术 2024年第4期20卷 70-77页

作者：倪廉钦李忠备高杰付光胜张晓玉袁安营安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室安徽淮南232001 伍伦贡大学土木采矿环境与建筑工程学院新南威尔士伍伦贡2522 山西金晖万峰煤矿有限公司山西孝义032300 中国冶金地质总局青岛地质勘查院山东青岛266000 安徽理工大学经济与管理学院安徽淮南232001

为有效解决近距离薄煤层群开采首采层上、下邻近层大量卸压瓦斯涌入的治理问题,以某煤矿为研究对象,采用理论分析和数值模拟的方法,研究近距离薄煤层群开采条件下卸压瓦斯运移规律,并根据富集特征确定卸压瓦斯抽采钻孔的空间位置。研究... 详细信息

为有效解决近距离薄煤层群开采首采层上、下邻近层大量卸压瓦斯涌入的治理问题,以某煤矿为研究对象,采用理论分析和数值模拟的方法,研究近距离薄煤层群开采条件下卸压瓦斯运移规律,并根据富集特征确定卸压瓦斯抽采钻孔的空间位置。研究结果表明:首采层开采覆岩导气裂隙带最大发育高为10.3~23.2 m。设计超大直径顺层预抽钻孔高0.8 m,宽2.08 m;顶板定向长钻孔终孔最优抽采位置为垂直距离开采层顶板15.0~23.0 m,水平距离回风侧20.5~27.5 m;2条埋管抽采最佳错距为距底板高1.1,1.7 m,深入采空区11.3,20.8 m。优化后的布置参数应用于现场实践,试验工作面回采期间上隅角瓦斯体积分数保持在0.7%以下。研究结果能够实现近距离薄煤层群开采条件下卸压瓦斯高效抽采,保证矿井安全高效生产。

关键词：近距离薄煤层群裂隙发育协同抽采超大直径顺层钻孔顶板定向长钻孔埋管抽采

Electrical and thermal transport properties of CdO ceramics

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1644-1648页

作者： Lü Qing WANG ShuFang LI LongJiang WANG JiangLong DAI ShouYu YU Wei fu guangsheng Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and Technology Hebei University

High temperature electrical and thermal transport properties,that is,electrical conductivity,Seebeck coefficient and thermal conductivity,of CdO ceramics have been *** of the good electrical properties and low thermal conductivity,the dimensionless figure-of-merit ZT of the CdO ceramics reaches 0.34 at 1023 *** value is comparable to the best reported ZT for the n-type oxide ceramic thermoelectric materials and remains as potential to be further improved by porosity controlling or nanostructuring.

关键词： CdO ceramics electrical transport properties thermal conductivity solid state reaction

Signal enhancement of the laser-induced plasma in the soil mixed with carbon

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Chinese Science Bulletin 2010年第4期55卷 386-389页

作者： ZHANG QiuLin ZHANG JinPing ZHANG Lei LI Xu GUO QingLin fu guangsheng Hebei Key Laboratory of Optoelectronic Information Materials Hebei University Baoding 071002 China

An experimental investigation of the carbon concentration effects on the emission intensity has been carried out using laserinduced plasma spectroscopy. The results show that the intensity of Ca II 393.367 nm and 396.847 nm characteristic lines emitted in the sample with the carbon concentration of 25% is about five times larger than that in the pure soil sample. It can be attributed to the high heat transfer coefficient and low ionization potentials of carbon in the system. Using the best experimental condition, quantitative analysis of the trace element of lead is conducted and the detection limit of lead concentration is estimated to be below 0.02%.

关键词：激光等离子体土壤碳信号增强混合等离子体光谱土壤样品排放浓度实验条件

Improving the efficiency of organic photovoltaic cells by introducing an ultrathin modification layer with a strong dipole moment

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Chinese Science Bulletin 2012年第14期57卷 1655-1658页

作者： fu guangsheng KONG WeiGuang HAN LingJie YANG QiMan HOU LiXin YANG ShaoPeng College of Physics Science and Technology Hebei University Baoding 071002 China China Lucky Film Corporation Baoding 071054 China

A method to improve the efficiency of organic photovoltaic cells through inclusion of an ultrathin modification layer of Al2O3 or LiF sandwiched between poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid(PEDOT:PSS) and indium tin oxide layers is *** of the strong dipole moments of LiF and Al2O3,either can enhance the built-in electric field,which increases the probability of the carriers reaching the corresponding *** addition,the low work function of PEDOT:PSS can decrease the energy barrier for carrier transmission.A 21.7% improvement in the power conversion efficiency of experimental devices was achieved,mainly because the short circuit current was enhanced by almost 30%.

关键词：有机光伏电池偶极矩改性层超薄 PEDOT 聚苯乙烯磺酸电源转换效率铟锡氧化物

Photovoltaic characteristics of Ca_3Co_4O_9/Nb-doped SrTiO_3 heterojunction

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 772-775页

作者： WANG ShuFang LIU fuQiang YAN GuoYing CHEN ShanShan CHEN JingChun WANG JiangLong Yu Wei fu guangsheng Hebei Key Lab of Optic-electronic Information and Materials Hebei UniversityBaoding 071002China

Ca3Co409/Nb-SrTiO3 heterojunction with good rectifying behavior at room temperature was fabricated by growing a layer of Ca3Co409 film on the lwt% Nb-doped SrTiO3 substrate by means of the chemical solution deposition technique. A large open-circuit voltage signal with the response time of tens of nanosecond was observed at room temperature when the Ca3Co409 layer of the heterojunction was illuminated under the 308 nm irradiation and no voltage signal was detected under the 10.6 gun irradiation. A mechanism based on the photovoltaic effect of a p-n junction was proposed to explain the experimental results. The present work shows a great potential of this new heterojunction as photoelectric devices.

关键词： photovoltaic effect heterojunction layered cobalt oxides chemical solution deposition

Enhancing the power conversion efficiency of PCDTBT:PC_(71)BM polymer solar cells using a mixture of solvents

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Chinese Science Bulletin 2014年第3期59卷 297-300页

作者： Shaopeng Yang Ye Zhang Tao Jiang Xuefeng Sun Chaoqun Lu Guang Li Xiaowei Li guangsheng fu Hebei Key Laboratory of Optic-electronic Information Materials College of Physics Science and TechnologyHebei University

Organic polymer solar materials are shown to exhibit better solubility in mixed solvents than in pure ones,which affects the performance of their solar *** this article,poly[N-9-hepta-decanyl-2,7-carbazole-alt-5,5-(4.7-di-2-thienyI-2,l,3-benzothiadiazole)(PCDTBT0)and[6,6]-phenyl-C71-butyric acid methyl ester(PC_(71)BM)are used as active layer materials in solar *** optimize the performance of these active materials,the ratio of chloroform(CF)to chlorobenzene used as solvents to dissolve PCDTBT,and PC_(71)BM is varied,which is shown to affect power conversion efficiency(PCE).The solar cell that shows the best performance with a PCE as high as 6.82%is produced using a volume ratio of CF to chlorobenzene of1:1.

关键词：太阳能电池材料有机聚合物电源转换效率溶剂比混合物功率转换效率最佳性能苯并噻二唑

Carbon Nitride Thin Films Deposited by Plasma Assisted Nd∶YAG Laser Ablation of Graphite in N2+H2 Atmosphere

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Chinese Journal of Lasers 2001年第6期10卷 56-60页

作者： YU Wei WANG Shufang ZHANG Lianshui LI Xiaowei fu guangsheng (College of Physics Science and Technology, Hebei University, Baoding 071002, China) 河北大学物理科学与技术学院河北保定 071002

Carbon nitride thin films are deposited on silicon wafers by 532 nm Nd∶YAG laser ablation of graphite in the N 2+H 2 atmosphere assisted by a dc glow discharge plasma at a higher gas pressure of about 4.0 kPa. The properties of the thin films are investigated by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD). The results show that the deposited films are composed of α-C 3N 4, β-C 3N 4 phase and have the N/C atomic ratio of 2.01. The optical emission spectroscopy (OES) studies indicate that the introduction of a dc glow discharge and the adoption of a higher gas pressure during the film deposition are favorable to the net generation of the atomic N, CN radicals and N + 2 in B 2Σ + u excited state in the plasma, which are considered to play a major role in the synthesis of carbon nitride.

关键词： pulsed laser deposition dc glow discharge carbon nitride