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数字经济赋能乡村劳动力高质量就业:内在机理、现实困境及实现路径研究

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贵阳学院学报（社会科学版） 2024年第3期19卷 111-116页

作者：张宏胜贵阳人文科技学院文化旅游与区域发展学院贵州贵阳550025

数字经济如何让数字技术发挥其提升乡村劳动力高质量就业的价值,是解决乡村剩余劳动力就业从而实现共同富裕的关键。数字经济基于数据资源赋能乡村劳动力高质量就业,利用数字经济的平台化、多元化、智慧化等特征促进乡村劳动力高质量就... 详细信息

数字经济如何让数字技术发挥其提升乡村劳动力高质量就业的价值,是解决乡村剩余劳动力就业从而实现共同富裕的关键。数字经济基于数据资源赋能乡村劳动力高质量就业,利用数字经济的平台化、多元化、智慧化等特征促进乡村劳动力高质量就业富于多样性、持续性、高效性等特点。本文通过厘清数字经济赋能乡村劳动力高质量就业的内在逻辑和现实困境,发现当前数字经济赋能乡村劳动力高质量就业存在数字技术人才与技术薄弱、农民数字技术岗位胜任力较弱、就业信息“生态链”建设不完善、就业基础设施及公共服务建设滞后等困境。有鉴于此,文章从优化数字经济促进就业体系完善、链接数字经济资源、完善数字经济就业信息生态、推动就业服务数字化转型等方面,探索数字经济赋能乡村劳动力高质量就业的实现路径。

关键词：数字经济赋能乡村劳动力就业实现路径

秦岭北麓地区CO_(2)和水汽湍流输送实验研究

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中国环境科学 2024年第5期44卷 2407-2417页

作者：彭艳赵奎锋张璐张宏昇李星敏陕西省气象科学研究所秦岭和黄土高原生态环境气象重点实验室陕西西安710016 陕西省气象局秦岭和黄土高原生态环境气象重点实验室陕西西安710016 北京大学物理学院大气与海洋科学系气候与海-气实验室北京100871

利用中国气象局秦岭气溶胶与云微物理野外科学试验基地长安站2021年4月~2022年3月涡动相关系统观测资料,结合气象观测资料,研究了秦岭北麓城郊过渡带近地面大气CO_(2)、H_(2)O浓度、蒸发量以及湍流通量演变特征,并讨论了气象要素对碳通... 详细信息

利用中国气象局秦岭气溶胶与云微物理野外科学试验基地长安站2021年4月~2022年3月涡动相关系统观测资料,结合气象观测资料,研究了秦岭北麓城郊过渡带近地面大气CO_(2)、H_(2)O浓度、蒸发量以及湍流通量演变特征,并讨论了气象要素对碳通量的影响.结果表明:观测时段内CO_(2)小时浓度年均值为(404.4±27.9)×10^(-6),与瓦里关大气背景观测站和全球背景观测站CO_(2)年均值浓度水平相当,水汽小时浓度年均值为9.44g/m^(3),年总蒸发量为1321.5mm;CO_(2)、水汽浓度和蒸发量均存在显著的月、季节变化特征;CO_(2)和水汽通量存在明显的日、月和季节变化,全年白天均表现为较强的碳吸收,观测时段内CO_(2)总吸收量约为-3047g/m^(2);夜间表现为碳排放,观测时段内总排放量约为2631g/m^(2);气温、土壤温度、相对湿度和风速的变化均会对区域内CO_(2)通量产生影响,温度升高会增加区域内植被的固碳能力;白天CO_(2)通量负值多出现在西风条件下,农田和植被覆盖率较大的区域为CO_(2)通量的主要贡献区域;夜间CO_(2)通量正值主要来自于植被、土壤呼吸作用和人类活动排放的贡献.总体而言,秦岭北麓城郊过渡带呈现较为明显的碳汇属性,实验时段内CO_(2)的净吸收量约为-416g/m^(2).

关键词： CO_(2)通量秦岭北麓城郊过渡带涡动相关气象因子

Cs/SiO_(2)催化合成MMA工艺及宏观动力学研究

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现代化工 2024年第1期44卷 210-215,220页

作者：贾鑫张伟王兴永张胜红傅送保姚志龙北京石油化工学院新材料与化工学院北京102617 恩泽生物质精细化工北京市重点实验室北京102617 中海油化工与新材料科学研究院(北京)有限公司北京102209

采用浸渍法制备了不同Cs质量分数的Cs/SiO_(2)催化剂,并利用XRD､氮气物理吸附､CO_(2)-TPD和NH3-TPD等技术对其进行表征。在固定床反应器中,优化了Cs/SiO_(2)催化丙酸甲酯与甲醛缩合制备甲基丙烯酸甲酯(MMA)的反应条件,并初步进行了动力... 详细信息

采用浸渍法制备了不同Cs质量分数的Cs/SiO_(2)催化剂,并利用XRD､氮气物理吸附､CO_(2)-TPD和NH3-TPD等技术对其进行表征。在固定床反应器中,优化了Cs/SiO_(2)催化丙酸甲酯与甲醛缩合制备甲基丙烯酸甲酯(MMA)的反应条件,并初步进行了动力学分析。结果表明,Cs质量分数为10%的Cs/SiO_(2)催化剂性能最优,在反应温度为370℃､反应空速为1.2 h^(-1)､酯醛摩尔比为1∶1的优化条件下,丙酸甲酯的转化率为46.3%,MMA的选择性接近100%。动力学分析显示丙酸甲酯与甲醛缩合制备MMA的表观活化能为39.1 kJ/mol,非常接近理论值。

关键词：甲基丙烯酸甲酯羟醛缩合丙酸甲酯宏观动力学

小煤窑破坏区下复采工作面自然发火隐患治理技术研究与应用

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兰州石化职业技术大学学报 2024年第2期24卷 23-27页

作者：张宏升卢树德兰州石化职业技术大学资源环境工程学院甘肃兰州730060 甘肃靖煤能源有限公司王家山煤矿分公司甘肃白银730913

通过对小窑破坏区下东一203复采工作面自然发火情况进行分析,采用钻探技术进行验证,提出了灌浆、注氮防灭火、开区均匀技术、采空区有害气体引排泄压、加强预测预报工作及现场监督管理等防灭火技术。该综合防灭火技术应用于东一203采煤... 详细信息

通过对小窑破坏区下东一203复采工作面自然发火情况进行分析,采用钻探技术进行验证,提出了灌浆、注氮防灭火、开区均匀技术、采空区有害气体引排泄压、加强预测预报工作及现场监督管理等防灭火技术。该综合防灭火技术应用于东一203采煤工作面,实现了工作面的安全顺利回采、回撤。

关键词：复采工作面自然发火防灭火技术

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流液道调节闸板球面座加工工艺的改进

建材世界 2024年第3期45卷 79-83页

作者：徐伟张宏盛潘云淇蚌埠凯盛工程技术有限公司蚌埠233010

流道闸板是通过控制调节闸板的升降来改变玻璃液的流通截面以达到调节和控制玻璃液流量的目的。该设备由闸板夹、吊挂闸板的横梁、立柱、自动升降传动系统及手动升降系统等组成。球面座是流液道调节闸板立柱的重要支撑零件,通过与涡轮... 详细信息

流道闸板是通过控制调节闸板的升降来改变玻璃液的流通截面以达到调节和控制玻璃液流量的目的。该设备由闸板夹、吊挂闸板的横梁、立柱、自动升降传动系统及手动升降系统等组成。球面座是流液道调节闸板立柱的重要支撑零件,通过与涡轮丝杠升降机主轴连接,使立柱上下移动从而带动横梁、闸板夹连同调节闸板上下移动,以达到调节玻璃液流量的目的。球面的形状结构要满足生产线装配现场位置旋转变化的需求,保证设备调试时调节闸板的两个立柱中心线所在平面必须垂直于水平面,且垂直于流液道中心线,同时保证丝杠连接闸板升降灵活无卡阻,因此对球面座的零件制作有特殊的工艺技术要求。

关键词：调节闸板柔性支撑异型零件拼焊结构工艺优化

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基于牛顿迭代法的抓斗挖泥船智能精挖控制方法

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中国港湾建设 2024年第2期44卷 98-104页

作者：张红升庞景墩陈磊中交疏浚技术装备国家工程研究中心有限公司上海200082

目前抓斗挖泥船在施工作业时大多依赖人工经验控制抓斗的闭合,在闭合过程中斗齿运动轨迹在竖直平面内的投影是一条曲线,进而导致抓斗控制精度低且作业区域高低不平。文章基于牛顿迭代法求解抓斗平挖运动控制方程,设计自动化程序控制抓... 详细信息

目前抓斗挖泥船在施工作业时大多依赖人工经验控制抓斗的闭合,在闭合过程中斗齿运动轨迹在竖直平面内的投影是一条曲线,进而导致抓斗控制精度低且作业区域高低不平。文章基于牛顿迭代法求解抓斗平挖运动控制方程,设计自动化程序控制抓斗升降绞车与开闭绞车转动速度,使斗齿运动轨迹在竖直平面内的投影为一条直线,其挖掘后形成的作业区域为平面。通过实例仿真试验证明,该方法有效提高了抓斗挖掘精度,节省疏浚工程作业量。研究结果可提升抓斗船作业能力,具有重要的工程应用价值。

关键词：抓斗挖泥船牛顿迭代法精挖控制疏浚工程

Hydrogel loaded with bone marrow stromal cell-derived exosomes promotes bone regeneration by inhibiting inflammatory responses and angiogenesis

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World Journal of Stem Cells 2024年第5期16卷 499-511页

作者： Shuai zhang Chuan Lu sheng Zheng Guang hong Division for International Collaborative and Innovative Dentistry Tohoku University Graduate School of DentistrySendai 980-8575MiyagiJapan School of Stomatology Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina

BACKGROUND Bone healing is a complex process involving early inflammatory immune regu-lation,angiogenesis,osteogenic differentiation,and *** repair poses challenges for orthopedic surgeons,necessitating the search for efficient healing *** To investigate the underlying mechanism by which hydrogel-loaded exosomes derived from bone marrow mesenchymal stem cells(BMSCs)facilitate the process of fracture *** Hydrogels and loaded BMSC-derived exosome(BMSC-exo)gels were charac-terized to validate their *** vitro evaluations were conducted to assess the impact of hydrogels on various stages of the healing *** could recruit macrophages and inhibit inflammatory responses,enhance of human umbilical vein endothelial cell angiogenesis,and promote the osteogenic differen-tiation of primary cranial ***,the effect of hydrogel on fracture healing was confirmed using a mouse fracture *** The hydrogel effectively attenuated the inflammatory response during the initial repair stage and subsequently facilitated vascular migration,promoted the formation of large vessels,and enabled functional vascularization during bone *** effects were further validated in fracture *** We successfully fabricated a hydrogel loaded with BMSC-exo that modulates macrophage polarization and angiogenesis to influence bone regeneration.

关键词： Hydrogel Bone marrow mesenchymal stem cells Macrophage polarization Angiogenesis Bone regeneration

Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin zhang Liang Liu Rui Bao Jian-hong Yi sheng-Da Guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He Si-yuan Feng Jian zhang hong-wu Tang Yang Xiao sheng Chen Chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM