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International Journal of mining Science and Technology 2022年第1期32卷 137-153页

作者： Meilu Yu Jianping Zuo Yunjiang sun Changning mi Zhengdai Li School of Mechanics&Civil Engineering China University of Mining&Technology(Beijing)Beijing 100083China State Key Laboratory of Coal Resources and Safe mining China University of Mining&Technology(Beijing)Beijing 100083China

Dynamic disasters,such as rock burst due to the breaking of large area stiff roof strata,are known to occur in the hard rock strata of coal *** this paper,mechanical models of the fracturing processes of thick hard rock strata were established based on the thick plate theory and numerical *** results demonstrated that,based on the fracture characteristics of the thick hard rock strata,four fracture models could be analyzed in detail,and the corresponding theoretical failure criteria were determined in *** addition,the influence of weak interlayer position on the fracture models and ground pressure of rock strata is deeply analyzed,and six numerical simulation schemes have been *** results showed that the working face pressure caused by the independent movement of the lower layer is relatively *** different fracture type of the thick hard rock strata had different demands on the working resistance of the hydraulic powered *** working resistance of the hydraulic powered supports required by the stratified movements was lower than that of the non-stratified movements.

关键词： Thick hard rock strata Thick plate theory Stratification movement of rock strata Numerical simulations Ground pressure distribution

Immobilized laccase on magnetic nanoparticles for enhanced lignin model compounds degradation

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Chinese Journal of Chemical Engineering 2020年第8期28卷 2152-2159页

作者： Xinyan Chen Bin He mi Feng Dingwei Zhao Jian sun Key Laboratory of Molecular Medicine and Biotherapy School of Life ScienceBeijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China

As a natural aromatic polymer,lignin has great potential but limited industrial application due to its complex chemical *** strategies for lignin conversion,biodegradation has attracted promising interest recently in term of efficiency,selectivity and mild *** order to overcome the issues of poor stability and non-reusability of enzyme in the biodegradation of lignin,this work explored a protocol of immobilized laccase on magnetic nanoparticles(MNPs)with rough surfaces for enhanced lignin model compounds *** electron microscope with energy dispersive spectrometer(SEM-EDS),flourier transformation infrared spectroscopy(FTIR)and thermal gravimetric analysis(TGA)were utilized to characterize the immobilization of *** results showed a maximum activity recovery of 64.7%towards laccase when it was incubated with MNPs and glutaraldehyde(GA)with concentrations of 6 mg·ml^-1and 7.5 mg·ml^-1for 5 h,*** immobilized laccase showed improved thermal stability and pH tolerance compared with free laccase,and remained more than 80%of its initial activity after 20 days of storage at 4℃.In addition,about 40%residual activity of the laccase remained after 8 times *** chromatography–mass spectrometry(GC–MS)was utilized to characterize the products of lignin model compound degradation and activation,and the efficiency of immobilized laccase was calculated to be 1–5 times that of free *** was proposed that the synergistic effect between MNPs and laccase displays an important role in the enhancement of stability and activity in lignin model compound biodegradation.

关键词： Laccase Immobilization Magnetic nanoparticles Lignin model compounds Degradation

Anti-aggregation growth and hierarchical porous carbon encapsulation enables the C@VO_(2) cathode with superior storage capability for aqueous zinc-ion batteries

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Journal of Energy Chemistry 2022年第4期31卷 645-654页

作者： ming Yang Yanyi Wang Zhongwei sun Hongwei mi Shichang sun Dingtao Ma Peixin Zhang College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060GuangdongChina College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055ShaanxiChina Shenzhen Hello Tech Energy Co. Ltd.Shenzhen 518100GuangdongChina Guangdong Engineering Technology Research Center for Distributed and Intelligent Small Solar Energy Storage Shenzhen 518100GuangdongChina

Self-aggregation and sluggish transport kinetics of cathode materials would usually lead to the poor electrochemical performance for aqueous zinc-ion batteries(AZIBs).In this work,we report the construction of C@VO_(2) composite via anti-aggregation growth and hierarchical porous carbon *** of the morphology of composite and pore structure of carbon layer can be regulated by tuning the adding amount of *** acting as cathode applied for AZIBs,the C@VO_(2)-3:3 composite can deliver a high capacity of 281 m Ah g^(-1) at 0.2 A g^(-1).Moreover,such cathode also exhibits a remarkably rate capability and cyclic stability,which can release a specific capacity of 195 m Ah g^(-1) at 5 A g^(-1) with the capacity retention of 95.4%after 1000 *** that,the evolution including the crystal structure,valence state and transport kinetics upon cycling were also deeply *** conclusion,benefited from the synergistic effect of anti-aggregation morphology and hierarchical porous carbon encapsulation,the building of such C@VO_(2) composite can be highly expected to enhance the ion accessible site,boost the transport kinetics and thus performing a superior storage *** design concept can be applied for other kinds of electrode materials and accelerating the development of highperformance AZIBs.

关键词： Aqueous zinc-ion batteries Anti-aggregation Hierarchical porous carbon encapsulation C@VO_(2)composite Storage mechanism

Design of ternary D flip-flop with pre-set and pre-reset functions based on resonant tunneling diode literal circuit

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 507-514页

作者： mi LIN Wei-feng LV Ling-ling sun Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China School of Electronics and lnformation Hangzhou Dianzi University Hangzhou 310018 China

The problems existing in the binary logic system and the advantages of multiple-valued logic (MVL) are introduced. A literal circuit with three-track-output structure is created based on resonant tunneling diodes (RTDs) and it has the most basic memory function. A ternary RTD D flip-flop with pre-set and pre-reset functions is also designed, the key module of which is the RTD literal circuit. Two types of output structure of the ternary RTD D flip-flop are optional: one is three-track and the other is single-track; these two structures can be transformed conveniently by merely adding tri-valued RTD NAND, NOR, and inverter units after the three-track output. The design is verified by simulation. Ternary flip-flop consists of an RTD literal circuit and it not only is easy to understand and implement but also provides a solution for the algebraic interface between the multiple-valued logic and the binary logic. The method can also be used for design of other types of multiple-valued RTD flip-flop circuits.

关键词： Resonant tunneling diode (RTD) Ternary logic Literal circuit D flip-flop

Compressive failure analysis of unidirectional carbon/epoxy composite based on micro-mechanical models

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Chinese Journal of Aeronautics 2017年第6期30卷 1907-1918页

作者： Wei sun Zhidong GUAN Zengshan LI mi ZHANG Yongjie HUANG School of Aeronautic Science and Engineering Beihang University Beijing 100083 China

A 2D micro-mechanical model was proposed to study the compressive failure of Uni Directional（UD） carbon/epoxy composite. Considering the initial imperfection and strength distribution of the fiber, the plasticity and ductile damage of the matrix, the failure of T300/914 UD composite under longitudinal compression and in-plane combined loads was simulated by this model. Simulation results show that the longitudinal compressive failure of the UD composite is caused by the plastic yielding of the matrix in kink band, and the fiber initial imperfection is the main reason for it. Under in-plane combined loads, the stress state of the matrix in kink band is changed, which affects the longitudinal compressive failure modes and strength of UD *** failure envelope of r_1–s_（12） and r_1–r_2 are obtained by the micro-mechanical model. Meanwhile,the compressive failure mechanism of the UD composite is analyzed. Numerical results agree well with the experimental data, which verifies the validity of the micro-mechanical model.

关键词： micro-mechanical model Unidirectional composite Initial imperfection Matrix plasticity Ductile damage Kink band

天山北麓中段绿洲带高砷地下水中砷的迁移转化规律

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地球科学 2024年第1期49卷 253-270页

作者：雷米周金龙周殷竹孙英韩双宝刘江涛鲁涵白凡闫志雲新疆农业大学水利与土木工程学院新疆乌鲁木齐830052 新疆水文水资源工程技术研究中心新疆乌鲁木齐830052 新疆水利工程安全与水灾害防治重点实验室新疆乌鲁木齐830052 中国地质调查局水文地质环境地质调查中心河北保定071051

准噶尔盆地是典型高砷地下水分布的内陆盆地,地下水作为盆地重要饮用水源,区域供水安全存在风险,高砷地下水迁移转化规律有待进一步查明.以天山北麓中段绿洲带为研究区,采用半变异函数模型和UNmiX源解析模型分析该区地下水砷的分布、地... 详细信息

准噶尔盆地是典型高砷地下水分布的内陆盆地,地下水作为盆地重要饮用水源,区域供水安全存在风险,高砷地下水迁移转化规律有待进一步查明.以天山北麓中段绿洲带为研究区,采用半变异函数模型和UNmiX源解析模型分析该区地下水砷的分布、地下水化学组分源贡献;结合地质条件、赋存环境与水文地球化学作用剖析典型剖面高砷地下水中砷的迁移转化与富集影响因素.结果表明:研究区地下水整体为弱碱性、偏还原环境的淡水,As含量在ND~887.0μg·L^(-1)之间,平均值为11.2μg·L^(-1),ρ(As)>10μg·L^(-1)的高砷地下水水化学类型以HCO_(3)·SO_(4)·Cl-Na(HSL-N型)和HCO_(3)·SO_(4)-Na(Na·Ca)型(HS-N(NC)型)为主.单一结构潜水、承压水区潜水、承压水中高砷地下水占比分别为0.4%、6.4%、18.6%,高砷地下水主要富集于冲积平原深度100~300 m的承压含水层中.原生矿物源、岩盐矿物源、土壤输入-人为排放源、硫酸-碳酸岩盐矿物源和环境影响源对地下水水化学组分贡献率分别为11.3%、21.1%、23.1%、23.4%和21.1%.25组典型剖面地下水样中,24组地下水砷形态为As(V)(占取样点的96.0%).沿着地下水流向,从山前倾斜平原到冲积平原,地下水总As含量呈先增大后减小的变化趋势.地下水砷富集不仅受到赋存环境中pH、Eh、HCO_(3)^(-)和PO_(4)^(3-)等水化学指标的影响,还与地质条件、水文地质条件、有机质降解和溶滤作用等因素有关.

关键词：高砷地下水空间分布源解析迁移转化水文地质

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多源性能约束的无人机可靠动态航路规划算法

中国惯性技术学报 2024年第2期32卷 187-195页

作者：孙淑光朱晓文中国民航大学电子信息与自动化学院天津300300 中国民航大学交通科学与工程学院天津300300

为提高无人机动态航路规划的安全性,提出一种基于机载导航系统实际导航性能和无人机机动性能的多源性能约束的改进A^(*)航路规划算法。分析了无人机航路规划系统架构及约束条件,构建了融合无人机最大允许转弯角、导航系统位置不确定度... 详细信息

为提高无人机动态航路规划的安全性,提出一种基于机载导航系统实际导航性能和无人机机动性能的多源性能约束的改进A^(*)航路规划算法。分析了无人机航路规划系统架构及约束条件,构建了融合无人机最大允许转弯角、导航系统位置不确定度和最短路径的加权启发函数,实现无人机动态航路规划的多约束适应性,最后进行了仿真分析验证。仿真结果表明:在相同的运行环境下,基于性能约束的改进A^(*)算法所规划航路的安全裕度比传统A^(*)算法提高1.8倍,角度变化百分比降低为传统算法的42.4%,航路规划用时缩短28%,所规划航路的安全裕度和无人机机动性能符合度都得到有效改善。

关键词：无人机航路规划位置不确定度机动性能航路安全性航路可行性改进A^(*)算法

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农田地膜使用信息监测系统设计与实现

中国农机化学报 2024年第8期45卷 302-307页

作者：徐靖孙池涛王鹏尹航米庆华柳平增山东农业大学信息科学与工程学院山东泰安271018 山东农业大学水利土木工程学院山东泰安271018 农业农村部农膜应用重点实验室山东泰安271018

开展农田地膜信息监测对科学使用地膜和治理农田白色污染具有重要意义。针对山东省农田地膜使用监测管理情况,利用信息技术与机器学习方法等手段,提出基于Springboot+Mysql+Mybatis为系统架构的山东省地膜监测系统研究模式,监测系统的... 详细信息

开展农田地膜信息监测对科学使用地膜和治理农田白色污染具有重要意义。针对山东省农田地膜使用监测管理情况,利用信息技术与机器学习方法等手段,提出基于Springboot+Mysql+Mybatis为系统架构的山东省地膜监测系统研究模式,监测系统的功能涵盖地膜使用监测网络的全部内容,包括地膜生产企业、地膜生产使用、回收与残留等全产业链关键业务数据报表的接收、上报、数据审核校验。同时实现数据综合分析,上报情况的统计,生产企业、监测点、审核单位和质量控制单位的基础信息管理,依托地膜使用监测上报数据,利用R语言对残留量与各类因子进行相关性分析以及方差分析,进一步精准农田地膜残留量预测模型设计。以2021年山东省农田地膜残留监测信息为依据,试运行系统,覆盖全省16地市122县,可实现地膜全产业链监测与信息共享,为地膜科学使用与管理提供技术支撑。

关键词：地膜残留功能设计数据分析数据上报污染防控

维普期刊数据库博看期刊

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基于PID控制的恒压模式压接技术研究

航天标准化 2024年第1期 53-57页

作者：武磊刘蜜刘林琳孙赫贵州航天电器股份有限公司贵阳550000 上海威克鲍尔通信科技有限公司上海200436

压接是指在自然环境下,采用压接工具或设备,使一种导线线芯与被连接连接器接触件发生机械挤压塑性变形而形成金属组织一体化的一种工艺方法。传统的导线与接触件的压接采用的是无压接压力控制的压接模式,仅在压接完成后通过金相检测设... 详细信息

压接是指在自然环境下,采用压接工具或设备,使一种导线线芯与被连接连接器接触件发生机械挤压塑性变形而形成金属组织一体化的一种工艺方法。传统的导线与接触件的压接采用的是无压接压力控制的压接模式,仅在压接完成后通过金相检测设备及拉力测试设备检查压接是否合格,该压接模式的应用有一定的局限性。在此基础上,设计了一套基于比例、积分、微分(PID)控制的恒压力压接的控制系统,该系统通过样机上验证,以400N压力为目标压力,压接了20个产品,压力的最大值为400.5N,最大偏差仅为0.125%,且压接的全部产品晶相检查均满足要求,证明基于PID控制的恒压力控制系统能有效的控制压接时的压力,提升产品的合格率,降低质量异常的风险。

关键词： PID 压接接触件导线

前列腺癌患者与主要照顾者相依关系对积极感受的影响

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国际医药卫生导报 2024年第13期30卷 2253-2259页

作者：张燕糜远源孙丽雅许源江南大学附属医院泌尿外科无锡214000

目的基于主客体互倚模型(APIM)探讨前列腺癌患者与其主要照顾者相依关系对积极感受的影响。方法该研究属于前瞻性、单中心试验。选取江南大学附属医院2021年5月至2023年5月收治的133例前列腺癌患者及其主要照顾者为研究对象,前列腺癌患... 详细信息

目的基于主客体互倚模型(APIM)探讨前列腺癌患者与其主要照顾者相依关系对积极感受的影响。方法该研究属于前瞻性、单中心试验。选取江南大学附属医院2021年5月至2023年5月收治的133例前列腺癌患者及其主要照顾者为研究对象,前列腺癌患者均为男性,年龄49~90(70.52±12.65)岁;主要照顾者男42名,女91名,年龄22~79(62.56±10.45)岁。参考相依关系量表(MS)、积极感受量表(PAC)调查患者与主要照顾者的相依关系、积极感受,采用t检验统计分析前列腺癌患者与主要照顾者相依关系评分、积极感受评分差异;采用Pearson分析前列腺癌患者与主要照顾者相依关系、积极感受的相关性;采用线性混合模型APIM分析前列腺癌患者与主要照顾者相依关系对积极感受的影响。结果前列腺癌患者的相依关系中爱和感情维度评分、总分均高于主要照顾者[(4.45±0.77)分比(2.62±0.55)分、(15.75±2.88)分比(13.60±2.25)分],积极感受中自我肯定、生活展望评分以及总分均低于主要照顾者[(12.34±2.11)分比(13.28±2.59)分、(13.46±2.53)分比(15.30±2.95)分、(25.80±4.25)分比(28.58±3.43)分],差异均有统计学意义(t=22.30、6.78、3.25、5.46、5.87,均P<0.05);患者相依关系与主要照顾者相依关系、积极感受呈正相关(r=0.887、0.718,均P<0.001),患者积极感受与主要照顾者相依关系、积极感受呈正相关(r=0.590、0.527,均P<0.001);主体效应上,患者及其主要照顾者的相依关系可影响自身的积极感受(β=0.474、0.485,均P<0.05);客体效应上,患者及其主要照顾者的相依关系可影响对方的积极感受(β=0.356、0.265、0.344、0.315,均P<0.05)。结论前列腺癌患者与其主要照顾者之间的相依关系评分与自身和对方的积极感受评分呈正相关,且经APIM模型验证其相依关系可正向影响二者积极感受。

关键词：前列腺癌主客体互倚模型主要照顾者相依关系积极感受