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基于物质-场分析的可拆卸矿用锚具的优化设计研究

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煤炭工程 2024年第1期56卷 127-133页

作者：罗文毛爱菊杨俊彩范润喜彭鹏国能神东煤炭有限责任公司陕西榆林719315 天津市振华预应力技术有限公司天津300385

预应力锚固技术在煤矿巷道顶板支护中被广泛应用,但目前针对预应力锚索锚固结构的卸锚仍采用手工操作,缺乏安全成熟的研究和成果。本研究分析了锚环-夹片-锚索三者之间物质-场关系,确定了传统矿用锚具卸锚过程中的关键问题,通过消除非... 详细信息

预应力锚固技术在煤矿巷道顶板支护中被广泛应用,但目前针对预应力锚索锚固结构的卸锚仍采用手工操作,缺乏安全成熟的研究和成果。本研究分析了锚环-夹片-锚索三者之间物质-场关系,确定了传统矿用锚具卸锚过程中的关键问题,通过消除非有效完整功能的物质-场模型、减缓有害功能的物质-场模型等两个方面进行分析,借助实验室试验对其进行结构优化。最终提出一种可拆卸矿用锚具,并在井下进行了应用试验。试验结果表明,相较于目前常用的矿用锚具,论文提出的可拆卸矿用锚具在实现快速高效拆除的同时,所需拆卸力小,锚索剩余应力实现归零,卸锚过程安全可靠。

关键词：预应力锚固技术预应力支护锚索矿用锚具锚具拆卸物质-场分析

补连塔煤矿回采巷道锚索主动式超前支护技术应用

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煤炭工程 2024年第2期56卷 59-65页

作者：杨俊彩范东林陈苏社刘兆祥王庆雄李金刚崔立军国能神东煤炭集团有限责任公司陕西神木719315 内蒙古煤炭科学研究院有限责任公司内蒙古呼和浩特010010

为了实现神东矿区综采工作面的无人化、少人化,降低工人劳动强度,以补连塔煤矿22406综采工作面为背景,采用理论分析计算与现场实测相结合的研究方法对工作面主运巷采用锚索主动式超前支护方式的科学性和合理性开展了研究,同时引用两侧... 详细信息

为了实现神东矿区综采工作面的无人化、少人化,降低工人劳动强度,以补连塔煤矿22406综采工作面为背景,采用理论分析计算与现场实测相结合的研究方法对工作面主运巷采用锚索主动式超前支护方式的科学性和合理性开展了研究,同时引用两侧实体煤巷道力学模型对主运巷专用锚索超前支护设计进行验证,通过验证“排距3 m,每排2套”的超前支护形式满足工作面超前支护要求。通过主运巷道超前支护段锚杆(索)受力监测可知,工作面推进过程中,超前支承压力的影响范围约为42 m,在距工作面10~26 m范围,超前支承压力增加幅度较大,应力集中系数为1.23~1.5。通过巷道围岩表面位移监测可知,主运巷在距离回采工作面35 m左右受采动影响开始变形,回采过程中,顶板最大下沉量达到16 mm,底板最大底鼓量达到42 mm,两帮最大移近量达到45 mm。研究结果表明,采用锚索补强超前支护方式,巷道围岩得到有效控制,围岩整体稳定且变形可控,现场应用效果良好。

关键词：神东矿区超前支护锚索主运巷矿压显现

Systematic error analysis and compensation for high accuracy star centroid estimation of star tracker

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Science China(Technological Sciences) 2010年第11期53卷 3145-3152页

作者： JIA Hui yang JianKun LI XiuJian yang juncai yang MengFei LIU YiWu HAO YunCai Institute of Technique Physics Science CollegeNational University of Defense TechnologyChangsha 410037China Beijing Institute of Control Engineering National Laboratory of Space Intelligent ControlBeijing 100190China China Academy of Space Technology Beijing 100094China

Subpixel centroid estimation is the most important star image location method of star tracker. This paper presents a theoretical analysis of the systematic error of subpixel centroid estimation algorithm utilizing frequency domain analysis under the con-sideration of sampling frequency limitation and sampling window limitation. Explicit expression of systematic error of cen-troid estimation is obtained, and the dependence of systematic error on Gaussian width of star image, actual star centroid loca-tion and the number of sampling pixels is derived. A systematic error compensation algorithm for star centroid estimation is proposed based on the result of theoretical analysis. Simulation results show that after compensation, the residual systematic errors of 3-pixel-and 5-pixel-windows’ centroid estimation are less than 2×10-3 pixels and 2×10-4 pixels respectively.

关键词： star tracker star image location subpixel centroid estimation centroid algorithm frequency domain analysis systematic error compensation

Three New Hydroxytetradecenals from Amomum tsao-ko with Protein Tyrosine Phosphatase 1B and Glycogen Phosphorylase Inhibitory Activity

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 875-883页

作者： Xiaolu Qin Xinyu Li Yi yang Mei Huang Shengli Wu Pianchou Gongpan Lianzhang Wu juncai He Changan Geng State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming650201China Nujiang Green Spice Industry Research Institute Lushui673100China University of Chinese Academy of Sciences Beijing100049China

The fruits of Amomum tsao-ko(Cao-Guo)were documented in Chinese Pharmacopoeia for the treatment of abdominal pain,vomiting,and *** our previous study,a series of diarylheptanes and flavonoids withα-glucosidase and protein tyrosine phosphatase 1B(PTP1B)inhibitory activity have been reported from the middle-polarity part of ***-ko,whereas the antidiabetic potency of the low-polarity constituents is still *** this study,three new hydroxytetradecenals,(2E,4E,8Z,11Z)-6R-hydroxytetradeca-2,4,8,11-tetraenal(1),(2E,4E,8Z)-6R-hydroxytetradeca-2,4,8-trienal(2)and(2E,4E)-6R-hydroxytetradeca-2,4-dienal(3)were obtained from the volatile oils of *** structures of compounds 1–3 were determined using spectroscopic data involving 1D and 2D nuclear magnetic resonance(NMR),high-resolution mass spectra(HRMS),and specific rotation([α]D).Their hypoglycemic activity was evaluated against glycogen phosphorylase(GPa)and *** 1 and 2 displayed moderate activity against PTP1B with inhibition rates of 33.8%−50.3%at 100 and 200μ***,compound 1 exhibited an obvious inhibitory effect on GPa(IC50=31.7μM),whereas compound 2 was *** study demonstrates hydroxytetradecenals as the characteristic components of ***-ko with therapeutic potential in diabetes.

关键词： Cao-Guo PTP1B and GPa inhibitors diabetes mellitus volatile oils

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神东矿区新型沿空留巷技术装备研究与应用

煤炭科学技术 2022年第S2期50卷 113-120页

作者：杨俊彩国能神东煤炭集团有限责任公司陕西榆林719315

神东矿区近年来推广应用了以柔模混凝土墙沿空留巷为代表的无煤柱开采技术,虽然技术适用性较好,但仍存在作业机械化程度低、劳动强度高、辅助运输压力大、作业环境差、工作面接续不连续等问题。针对这些难题,神东公司优化巷道设计和设... 详细信息

神东矿区近年来推广应用了以柔模混凝土墙沿空留巷为代表的无煤柱开采技术,虽然技术适用性较好,但仍存在作业机械化程度低、劳动强度高、辅助运输压力大、作业环境差、工作面接续不连续等问题。针对这些难题,神东公司优化巷道设计和设备布置,应用远程供电供液技术,将乳化液泵站、移动变电站及配套供电设备集中布置在运输平巷外,实现设备多面共用,减少设备搬迁,缩短材料运输距离,增大运输、行人安全空间,减少留巷与采煤作业的时空干扰。应用水力压裂或爆破卸压的方法降低留巷区域巷道矿压显现,减少支护投入,扩大留巷范围。研制内嵌式、抗剪切式锚索等专用支护材料,挡矸支架、单元(门式)支架等专用支护装备,全面替代传统的“一梁四柱”架棚支护形式,降低劳动强度,改善支护效果。将井下拌合混凝土改为地面制备商砼,提高砼料质量和生产效率,研制砼运输专用车辆,减少砼料运输过程中离析与抛洒,提高运输效率。优化模袋设计工艺,引进新型薄喷材料,减少了漏风通道,改进工作面通风方式,提高了灾害防治和安全保障能力。新工艺变革了传统低效、高风险、劳动密集型留巷工艺,取得了日留巷18 m、月留巷418 m的纪录。同时留巷用工由26人减少到17人,用工数较传统工艺下降了35%,效率提升了50%,实现了减人增效,为矿区无煤柱安全高效开采提供了新方案。

关键词：沿空留巷高效安全装备混凝土泵送车单元支架门式支架

Experimental and simulation research on hollow AZ31 magnesium alloy three-channel joint by hot extrusion forming with sand mandrel

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Journal of Magnesium and Alloys 2024年第1期12卷 98-109页

作者： Shi Shengnan Wang Hongyu Teng Fei Jiang Lei Sun juncai Sun Jie Zhang Shunhu Transportation Engineering College Dalian Maritime UniversityDalianLiaoning 106026China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyangLiaoning 110819China Shagang School of Iron and Steel Soochow UniversitySuzhouJiangsu 215021China

Magnesium alloy is one of the lightest metal structural *** weight is further reduced through the hollow ***,the hollow structure is easily damaged during *** order to maintain the hollow structure and to transfer the stresses during the high temperature deformation,the sand mandrel is *** this paper,the hollow AZ31 magnesium alloy three-channel joint is studied by hot extrusion *** as one of solid granule medium is used to fill the hollow magnesium *** extrusion temperatures are 230℃ and 300℃,*** process parameters(die angle,temperature,bottom thickness,sidewall thickness,edge-to-middle ratio in bottom,bottom shape)of the hollow magnesium alloy are analyzed based on the results of experiments and the finite element *** results are shown that the formability of the hollow magnesium alloy will be much better when the ratio of sidewall thickness to the bottom thickness is 1:*** when edge-to-middle ratio in bottom is about 1:1.5,a better forming product can be *** best bottom shape in these experiments will be convex based on the forming *** grain will be refined obviously after the *** the microstructures will be shown as *** these lines will be well agreement with the mold in the corner.

关键词： AZ31 magnesium alloy Three-channel joint Sand Experiments and the finite element Die angle

An effective strategy for dendrite free Li metal anodes:Nickel foam decorated with high lattice-matching CoN and CoF_(2) nanosheets for dense deposition

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Nano Research 2024年第5期17卷 4069-4078页

作者： Wenlong Liu Jianzong Man Xiaodong Sun Ning Zhang Yehong Du Kun Liu Zhongsheng Wen Song Li juncai Sun Institute of Materials and Technology Dalian Maritime UniversityDalian 116026China Shandong Provinvial Key Laboratory of Chemical Energy Storage and Novel Cell Technology and School of Chemistry and Chemical enginneringLiaocheng UniversityLiaocheng 252000China Department of Public Security Management Liaoning Police CollegeDalian 116036China

The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/***,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free *** Ni foam offers abundant space to receive deposited Li *** CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)***,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and ***,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI *** the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic *** strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.

关键词： CoN and CoF_(2) lattice-matching nanosheet lithiophilicity lithium metal anodes

An Effective Power Optimization Approach Based on Whale Optimization Algorithm with Two-Populations and Mutation Strategies

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Chinese Journal of Electronics 2024年第2期33卷 423-435页

作者： juncai HE Zhenxue HE Jia LIU Yan ZHANG Fan ZHANG Fangfang LIANG Tao WANG Limin XIAO Xiang WANG Hebei Agricultural University Beijing Information Science and Technology University School of Computer Science and Engineering Beihang University School of Electronic and Information Engineering Beihang University

Power is an issue that must be considered in the design of logic circuits. Power optimization is a combinatorial optimization problem, since it is necessary to search for a logical expression that consumes the least amount of power from a large number of Reed-Muller(RM) logical expressions. The existing approach for optimizing the power of multi-output mixed polarity RM(MPRM) logic circuits suffer from poor optimization results. To solve this problem, a whale optimization algorithm with two-populations strategy and mutation strategy(TMWOA) is proposed in this paper. The two-populations strategy speeds up the convergence of the algorithm by exchanging information about the two-populations. The mutation strategy enhances the ability of the algorithm to jump out of the local optimal solutions by using the information of the current optimal solution. Based on the TMWOA, we propose a multi-output MPRM logic circuits power optimization approach(TMMPOA). Experiments based on the benchmark circuits of the Microelectronics Center of North Carolina(MCNC) validate the effectiveness and superiority of the proposed TMMPOA.

关键词： Logic circuits Benchmark testing Search problems Whale optimization algorithms Microelectronics Optimization Convergence

柔模砼墙沿空留巷围岩变形规律及控制技术研究

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煤炭科学技术 2022年第S1期50卷 89-99页

作者：杨俊彩王文张广杰国能神东煤炭集团有限责任公司陕西神木719315 河南理工大学能源科学与工程学院河南焦作454003 煤炭安全生产与清洁高效利用省部共建协同创新中心河南焦作454000

为解决柔模砼墙沿空留巷围岩变形破坏严重的难题,以大柳塔煤矿52605工作面为工程地质背景,对沿空巷道围岩结构演化特性作了研究分析,提出采用无机注浆加固、加强顶帮结构及提高巷内高阻支护等综合方式确保沿空留巷稳定性,并进行了现场... 详细信息

为解决柔模砼墙沿空留巷围岩变形破坏严重的难题,以大柳塔煤矿52605工作面为工程地质背景,对沿空巷道围岩结构演化特性作了研究分析,提出采用无机注浆加固、加强顶帮结构及提高巷内高阻支护等综合方式确保沿空留巷稳定性,并进行了现场试验。结果表明:引起留巷围岩破坏的关键是上覆顶板下位关键岩层形成“悬臂梁结构”而将压力传递至巷道上;采用无机注浆加固材料能够改善巷道四周煤岩体的应力环境,形成再造承载层结构,提高留巷整体承载能力;滞后工作面180 m后留巷变形趋于稳定,顶板下沉最大246 mm、两帮收缩量最大315 mm、底鼓最大275 mm,能够控制住留巷破坏。为类似工程地质条件下的柔模墙沿空留巷的实施提供科学的技术指导。

关键词：柔模砼墙沿空留巷围岩结构注浆加固关键岩层顶板