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Dynamic leakage mechanism of gas drainage borehole and engineering application

International Journal of Mining Science and Technology 2018年第3期28卷 505-512页

作者： zhang junxiang Li Bo Sun Yuning School of Energy Science and Engineering Henan Polytechnic University Jiaozuo 454003 China State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University Jiaozuo 454003 China Collaborative Innovation Center of Coal Safety Production of Henan Province Jiaozuo 454003 China State and Local Joint Engineering Laboratory for Gas Drainage & Ground Control of Deep Mines Henan Polytechnic University fiaozuo 454003 China

Borehole leakage not only affects the gas drainage effect but also presents considerable risk to human security. For the research on the leakage mechanism of gas drainage borehole, the rheological and visco-elastic-plastic characteristics were considered to establish the mechanical model of coal mass around borehole, which is used to analyze the leakage mechanism and deduce the dynamic leakage model. On the basis of the real coal seam conditions, the variation rules of the stress, leakage ring, and air leakage amount were analyzed through numerical simulation, and the influence factors of air leakage amount were also investigated to provide the theoretical basis for the sealing technology. Results show that the air leakage amount of borehole is inversely proportional to the increase in supporting stress and sealing length, and directly correlated with the increase in borehole radius and softening modulus. Using theoretical analysis, we design a novel active supporting sealing technology that can use grouting material to seal the fractures to reduce the leakage channels and also provide supporting stress to prevent borehole deformation. The engineering test results indicate that the average gas concentration with the novel active supporting sealing technology is increased by 162.12% than that of traditional polyurethane sealing method. Therefore, this technology not only effectively resolves borehole leakage but also significantly improves the gas drainage effect.

关键词：排水效果煤气地上机制工程机械模型穿漏

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57 W 2.05μm单横模掺铥光纤激光MOPA

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中国激光 2024年第8期51卷 32-37页

作者：罗学文张露付士杰盛泉张钧翔史伟姚建铨天津大学精密仪器与光电子工程学院天津300072 天津大学光电信息技术教育部重点实验室天津300072

基于商用单模掺铥石英光纤设计了高功率2.05μm波段全光纤主振荡功率放大器(MOPA)。以自制环形腔掺铥光纤激光器为种子,利用级联滤波型波分复用器优化长波长种子的光信噪比,基于MOPA结构实现了高效的高功率输出。基于速率方程模型,理论... 详细信息

基于商用单模掺铥石英光纤设计了高功率2.05μm波段全光纤主振荡功率放大器(MOPA)。以自制环形腔掺铥光纤激光器为种子,利用级联滤波型波分复用器优化长波长种子的光信噪比,基于MOPA结构实现了高效的高功率输出。基于速率方程模型,理论分析了主放大级的注入信号光功率和增益光纤长度的优化关系;实验中在102.6 W的793 nm泵浦功率下获得了输出功率为57 W、光谱线宽为0.08 nm、光信噪比为58.8 dB的单横模激光输出,主放大级斜效率为52.6%。

关键词：激光器掺铥光纤激光器 2μm激光单模光纤激光器速率方程

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基于京东商城在线评论的国产干红葡萄酒消费特征分析

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中外葡萄与葡萄酒 2024年第1期 112-118页

作者：戈文尚程梦琳张军翔仉瑞宁夏大学葡萄酒与园艺学院宁夏银川750021 宁夏葡萄与葡萄酒研究院宁夏银川750021 宁夏大学经济管理学院宁夏银川750021

移动终端的全民普及重塑了买卖双方的交互关系,消费者发布线上评论的热情持续高涨,各大电商平台由此产生的评论数据为解决企业对消费者需求、了解产品不足提供了突破口。本文以京东商城国产干红葡萄酒的在线评论为数据来源,通过Python... 详细信息

移动终端的全民普及重塑了买卖双方的交互关系,消费者发布线上评论的热情持续高涨,各大电商平台由此产生的评论数据为解决企业对消费者需求、了解产品不足提供了突破口。本文以京东商城国产干红葡萄酒的在线评论为数据来源,通过Python对评论内容进行提取,分析了消费者对产品不同属性的关注点及关注程度。结果表明,消费者的关注点集中在干红葡萄酒的口感、物流服务、性价比和品牌知名度等方面。这可为酒庄新品开发、产品定价、售后服务和品牌建设及管理等带来启示,并为产品数字化精准营销提供决策依据。

关键词：干红葡萄酒在线评论消费特征 Python

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Application of Contact Graph Routing in Satellite Delay Tolerant Networks

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空间科学学报 2015年第1期35卷 116-125页

作者： ZHU Laitao LI Yong zhang junxiang WU Jing TAI Xiao ZHOU Jianguo School of Electronic Information Wuhan University Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory

Satellite networks have many inherent advantages over terrestrial networks and have become an important part of the global network infrastructure.Routing aimed at satellite networks has become a hot and challenging research topic.Satellite networks,which are special kind of Delay Tolerant Networks(DTN),can also adopt the routing solutions of DTN.Among the many routing proposals,Contact Graph Routing(CGR) is an excellent candidate,since it is designed particularly for use in highly deterministic space networks.The applicability of CGR in satellite networks is evaluated by utilizing the space oriented DTN gateway model based on OPNET(Optimized Network Engineering Tool).Link failures are solved with neighbor discovery mechanism and route recomputation.Earth observation scenario is used in the simulations to investigate CGR's performance.The results show that the CGR performances are better in terms of effectively utilizing satellite networks resources to calculate continuous route path and alternative route can be successfully calculated under link failures by utilizing fault tolerance scheme.

关键词： Satellite Delay Tolerant Networks(DTN) Space oriented DTN gateway Contact Graph Routing(CGR) Link failures

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Pump quantum efficiency optimization of 3.5 μm Er-doped ZBLAN fiber laser for high-power operation

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Frontiers of Optoelectronics 2023年第4期16卷 13-23页

作者： Lu zhang Shijie Fu Quan Sheng Xuewen Luo junxiang zhang Wei Shi Jianquan Yao Institute of Laser and Optoelectronics School of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjin 300072China Key Laboratory of Opto-Electronic Information Technology Ministry of EducationTianjin UniversityTianjin 300072China

976 nm+1976 nm dual-wavelength pumped Er-doped ZBLAN fiber lasers are generally accepted as the preferred solution for achieving 3.5μm lasing.However,the 2μm band excited state absorption from the upper lasing level(^(4 )F_(9/2)→^(4)F_(7/2))depletes the Er ions population inversion,reducing the pump quantum efciency and limiting the power scaling.In this work,we demonstrate that the pump quantum efciency can be efectively improved by using a long-wavelength pump with lower excited state absorption rate.A 3.5μm Er-doped ZBLAN fber laser was built and its performances at diferent pump wavelengths were experimentally investigated in detail.A maximum output power at 3.46μm of~7.2 W with slope efciency(with respect to absorbed 1990 nm pump power)of 41.2%was obtained with an optimized pump wavelength of 1990 nm,and the pump quantum efciency was increased to 0.957 compared with the 0.819 for the conventional 1976 nm pumping scheme.Further power scaling was only limited by the available 1990 nm pump power.A numerical simulation was implemented to evaluate the cross section of excited state absorption via a theoretical ftting of experimental results.The potential of further power scaling was also discussed,based on the developed model.

关键词： Fiber laser Mid-infrared Er-doped ZBLAN fiber Dual-wavelength pumping

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酿酒葡萄细胞壁多糖组分研究进展

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食品安全导刊 2024年第15期 155-161页

作者：姬欣欣张军翔高宇宁夏大学食品科学与工程学院宁夏大学葡萄酒与园艺学院

酿酒葡萄细胞壁成熟涉及果胶、纤维素、半纤维素等一系列多糖大分子组分的结构调控，同时酿酒葡萄品种、栽培处理与气候等因素也会影响果实成熟过程中细胞壁多糖的结构演化。酿酒葡萄成熟过程及酿造过程中细胞壁多糖组分的结构变化会影... 详细信息

酿酒葡萄细胞壁成熟涉及果胶、纤维素、半纤维素等一系列多糖大分子组分的结构调控，同时酿酒葡萄品种、栽培处理与气候等因素也会影响果实成熟过程中细胞壁多糖的结构演化。酿酒葡萄成熟过程及酿造过程中细胞壁多糖组分的结构变化会影响葡萄酒的品质。本文结合国内外研究进展，简要阐述了酿酒葡萄果实结构及其成熟过程中细胞壁多糖组分的微观修饰机制，同时讨论了葡萄品种、气候、栽培处理对酿酒葡萄果实细胞壁多糖的影响。此外，归纳了酿造过程中不同工艺处理下细胞壁多糖的降解机制，以期为酿酒葡萄细胞壁多糖的进一步研究提供理论参考。

关键词：酿酒葡萄果实细胞壁成熟多糖

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FreestandingMo_(3)N_(2) nanotubes for long-term stabilized 2e−intermediate-based high energy efficiency Li-CO_(2) batteries

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SusMat 2023年第2期3卷 276-288页

作者： Guicai Qi junxiang zhang Jianli Cheng Bin Wang Institute of Chemical Materials China Academy of Engineering PhysicsChengduChina Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengduChina

Li–CO_(2) batteries are considered one of the promising power sources owing to ultrahigh energy density and carbon fixation.Nevertheless,the sluggish reaction kinetics of 4e−discharged process(Li_(2)CO_(3))impede its potential application.One of the efficient strategies for developing cathode catalysts is to stabilize 2e−intermediate Li_(2)C_(2)O_(4) and improve reaction reversibility.However,longterm catalysts of stabilized Li_(2)C_(2)O_(4) are barely achieved,whereas cycle stability is far from satisfactory level.Herein,non-noble metal–based Mo_(3)N_(2) is synthesized and employed as freestanding cathodes for Li–CO_(2) batteries.Owing to rich delocalized electrons of Mo^(2+)and reversible electron localization structure,freestanding Mo_(3)N_(2) cathodes exhibit a low charge potential(3.28 V)with an ultralow potential gap(0.64 V),high energy efficiency of up to 80.46%,fast rate capability,and outstanding cycle stability(>910 h).In situ experiments and theoretical calculation verify that Mo_(3)N_(2) stabilizes 2e−Li_(2)C_(2)O_(4) intermediate by the interaction of Mo^(2+)as active sites where Mo^(2+)promotes the transfer of outer electrons to O,prevents its disproportionation to Li_(2)CO_(3),and promotes reaction kinetics,contributing to high energy efficiency and outstanding cycle reversibility.In addition,the pouch-cells deliver ultrahigh energy density of up to 6350.7W h kg^(−1) based on the mass of cathode materials.

关键词： carbon-free freestanding high energy efficiency Li-CO_(2)batteries Mo_(3)N_(2)nanotubes

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Copper Indium Sulfide Enables Li-CO_(2)Batteries with Boosted Reaction Kinetics and Cycling Stability

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Energy & Environmental Materials 2023年第5期6卷 372-380页

作者： Lin Chen Jingwen Zhou junxiang zhang Guicai Qi Bin Wang Jianli Cheng Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Yangtze Delta Region Institute Institute of Fundamental and Frontiers SciencesUniversity of Electronic Sciences and Technology of ChinaHuzhou 313001China Institute of Fundamental and Frontiers Sciences University of Electronic Sciences and Technology of ChinaChengdu 611731China Department of Chemistry City University of Hong KongKowloon Hong Kong China

High energy density Li-CO_(2)batteries have attracted much attention owing to the"two birds with one stone"feature in fixing greenhouse gas CO_(2)and providing renewable energy.However,poor reversibility of the discharge product Li_(2)CO_(3)is one of the main problems that limit its application,resulting in poor cycling stability and severe polarization.Herein,copper indium sulfide(CIS),a semiconducting non-precious metal sulfide,is fabricated as cathode catalysts for high-performance Li-CO_(2)batteries.Combined with the synergistic effect of bimetallic valence bonding and coordinated electron transfer,Li-CO_(2)batteries using CIS cathodes exhibit high full specific discharge capacity,excellent rate capability and cycle stability,namely it delivers a high specific full discharge capacity of 8878μAh cm^(-2),runs steadily from 10 to 100μA cm^(-2),and performs a stable long-term cycling behavior(>1050 h)under a high energy efficiency of 84%and a low charge voltage of approximately 3.4 V at 20μA cm^(-2)within 100μAh cm^(-2).In addition,a flexible Li-CO_(2)pouch cell is constructed to reveal the potential of employing CIS to fabricate flexible high energy storage devices in practical applications.This work shows a promising development pathway toward next-generation sustainable energy storage devices.

关键词： copper indium sulfides cycling stability Li-CO_(2)batteries reaction kinetics

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Effects of micro-oxygenation on the aroma of Cabernet Sauvignon wine from Ningxia,China

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 251-263页

作者： Zhong zhang Qingchen zhang Huiqing Wang Hongchuan Xia Lijun Sun junxiang zhang School of Life Sciences Ningxia UniversityYinchuan 750021China College of Pharmacy University of FloridaGainesville FL32610USA School of Agriculture Ningxia UniversityYinchuan 750021China School of Food and Wine Ningxia UniversityYinchuan 750021China China Wine Industry Technology Institute Yinchuan 750021China

Micro-oxygenation (MOX) is an effective post-harvest technique for the flavor improvement of grape wine. This study investigated the effect of MOX on the aroma quality of Ningxia wine for the first time. Three sub-region Cabernet Sauvignon dry red wines were treated with different levels of oxygen before or after malolactic fermentation. The wine aroma was analyzed through gas chromatography-mass spectrometry (GC-MS) and quantitative descriptive analysis (QDA) after six months of aging. The data obtained demonstrated that the dose and timing of oxygen addition were key factors influencing the effectiveness of MOX. The most noticeable modifications in wine aroma compounds were generated by an oxygen dosage of 30 (mL/L)/month added before malolactic fermentation. Predominantly, the concentrations of 2-phenylethanol, benzaldehyde, diacetyl, and 2,3-pentanedione showed an increased pattern upon MOX treatments. The sensory analysis revealed that MOX improved the aroma quality of wine by decreasing green and animal odors, meanwhile enhancing the olfactory intensities of dried fruits, flowers, and nuts. This work confirmed that MOX was suitable for aroma modification of Cabernet Sauvignon dry red wine from Ningxia and established a preliminary MOX procedure that can serve as a reference for future applications.

关键词： grape wine micro-oxygenation volatile organic compounds aroma profiles Ningxia

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A splice site mutation in the FvePHP gene is associated with leaf development and f lowering time in woodland strawberry

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Horticulture Research 2023年第1期10卷 274-287页

作者： Baotian Wang Weijia Li Kexin Xu Yingying Lei Di Zhao Xue Li junxiang zhang Zhihong zhang Liaoning Key Laboratory of Strawberry Breeding and Cultivation College of HorticultureShenyang Agricultural UniversityShenyang110866China Laboratory of Protected Horticulture(Shenyang Agricultural University) Ministry of EducationShenyang110866China Institute of Carbon Materials Science Shanxi Datong UniversityDatong037009China Analytical and Testing Center Shenyang Agricultural UniversityShenyang110866China

Leaves and f lowers are crucial for the growth and development of higher plants.In this study we identified a mutant with narrow leaf lets and early f lowering(nlef)in an ethyl methanesulfonate-mutagenized population of woodland strawberry(Fragaria vesca)and aimed to identify the candidate gene.Genetic analysis revealed that a single recessive gene,nlef,controlled the mutant phenotype.We found that FvH4_1g25470,which encodes a putative DNA polymeraseαwith a polymerase and histidinol phosphatase domain(PHP),might be the candidate gene,using bulked segregant analysis with whole-genome sequencing,molecular markers,and cloning analyses.A splice donor site mutation(C to T)at the 5-end of the second intron led to an erroneous splice event that reduced the expression level of the full-length transcript of FvePHP in mutant plants.FvePHP was localized in the nucleus and was highly expressed in leaves.Silencing of FvePHP using the virus-induced gene silencing method resulted in partial developmental defects in strawberry leaves.Overexpression of the FvePHP gene can largely restore the mutant phenotype.The expression levels of FveSEP1,FveSEP3,FveAP1,FveFUL,and FveFT were higher in the mutants than those in‘Yellow Wonder’plants,probably contributing to the early f lowering phenotype in mutant plants.Our results indicate that mutation in FvePHP is associated with multiple developmental pathways.These results aid in understanding the role of DNA polymerase in strawberry development.

关键词： straw PHP narrow

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