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Influence of desert sand on the mechanical properties of concrete subjected to impact loading

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Acta Mechanica Solida Sinica 2017年第6期30卷 583-595页

作者： Liu Haifeng Ma Jurong wang yiying Ning Jianguo School of Civil and Hydraulic Engineering Ningxia University State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

A74-mm-diameter Split Hopkinson pressure bar was used to carry out the dynamic compression experiment of concrete made of desert *** dynamic failure processes of concrete different in specimen size,impact velocity,desert sand replacement ratio,size and volume content of coarse aggregate were *** results showed that concrete made of desert sand had size-effect and was *** peak stress of concrete made of desert sand declined with the minimum size of coarse ***,the peak stress of concrete made of desert sand increased first,and then declined with the volume content and maximum size of coarse aggregate.

关键词： Concrete Desert sand Mechanical properties Impact loading

La_(2)O_(3)-modified BiYbO_(3)–Pb(Zr,Ti)O_(3) ternary piezoelectric ceramics with enhanced electrical properties and thermal depolarization temperature

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Journal of Advanced Ceramics 2023年第8期12卷 1593-1611页

作者： Yu Chen Lingfeng Li Zhi Zhou yiying wang Qiang Chen Qingyuan wang School of Mechanical Engineering Chengdu UniversityChengdu 610106China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China Institute for Advanced Study Chengdu UniversityChengdu 610106China

High-performance Pb(Zr_(1−x)Ti_(x))O_(3)(PZT)piezoceramics are urgently desired by the market in view of their expanded operating temperature range,reduced property temperature dependence,and enhanced sensitivity and acoustic *** this work,we reported a kind of low-cost and high-performance 0.06BiYbO_(3)–0.94Pb(Zr_(0.48)Ti_(0.52))O_(3) ternary piezoceramics;the modifying effects of La_(2)O_(3) on this perovskite system were investigated in terms of the structures,electrical properties,and thermal depolarization behaviors of *** field-dependent dielectric and conduction properties indicated that there are close correlations among oxygen vacancies(VO),conducting electrons,and intrinsic conduction *** degradation in ferroelectric properties observed in those samples doped with more than 0.15 wt%of La_(2)O_(3) indicated that the occupying mechanisms of La^(3+)changed from the donor substitution for Pb^(2+)to the isovalent substitution for Bi^(3+).The thermally depoling micromechanisms of ceramics were revealed from the thermodynamic processes of defect dipoles and intrinsic dipoles within ferroelectric *** sample doped with 0.15 wt%of La_(2)O_(3) shows excellent electrical properties with TC=387℃,d33=332 pC/N,TKε=5.81×10^(−3)℃−1,Pr=20.66μC/cm^(2),Td=356℃.The significantly enhanced electrical properties and thermal depolarization temperature benefited from the donor substitution of La3+,decreasing the oxygen vacancy concentration in the lattice and possibly optimizing the ferroelectric domain structure of ceramics.

关键词： BiYbO_(3)-Pb(Zr_(1−x)Ti_(x))O_(3)(BY-PZT)piezoceramics La_(2)O_(3) ferroelectric domain switching(Sswitch) defect dipoles thermal depolarization behaviors

Room temperature synthesis of flower-like CuS nanostructures under assistance of ionic liquid

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Frontiers of Optoelectronics 2011年第2期4卷 150-155页

作者： Chuyan CHEN Qing LI yiying wang Yuan LI Xiaolin ZHONG School of Materials Science and Engineering Education Ministry Key Laboratory on Luminescence and Real-Time AnalysisSouthwest University

Flower-like CuS nanostructures have been synthesized via a liquid precipitation route by the reaction between CuCl2.2H2O and thioacetamide（CH3CSNH2,TAA） in the ionic liquid 1-butyl-3-methyl imidazole six hexafluorophosphoric acid salts（[BMIM][PF6]） aqueous solution at room temperature. The products were characterized by X-ray powder diffraction（XRD）, field emission scanning electronic microscopy（FESEM）,Brunauer-Emmett-Teller（BET）, Ultraviolet-Visible Spectrophotometer（UV-Vis） and Photoluminescence（PL）techniques. The as-prepared CuS nanostructures have a mean diameter of about 1 μm. A plausible mechanism was proposed to explain the formation of CuS *** effects of experimental parameters on the formation of the products were also explored. With BET theory, it is found that the as-prepared CuS nanostructures have a specific area of 39 m2/g. The Barrett-Joyner-Halenda（BJH） pore size distribution of the as-prepared CuS nanostructures presents smaller pores centers about 60 nm. The UV-Vis and PL curves indicate that the asprepared CuS nanostructures are promising candidates for the development of photoelectric devices.

关键词： nanostructures liquid precipitation method ionic liquid

Effect of the electro-acupuncture on senile plaques and its formation in APPD/PS1D double transgenic mice

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Genes & Diseases 2019年第3期6卷 282-289页

作者： Qinghua Yang Shujuan Zhu Jin Xu Chenglin Tang Kaihui Wu Yanjun Wu yiying wang Huajun Sheng Institute of Neuroscience Chongqing Medical UniversityChongqingChina College of Traditional Chinese Medicine Chongqing Medical UniversityChongqingChina

Alzheimer’s disease(AD)is a progressive neurodegenerative disease and its incidence will increase with age and is *** senile plaques(SPs)are one of three main pathological features in AD patients,which are formed by amyloid b-protein(Ab)overaccumulation.b-amyloid precursor protein(APP),b-site APP cleavage(BACE1),and insulin degrading enzyme(IDE)proteins participate in the process of Ab production and *** present,the pathogenesis of AD is not yet clear and the current treatment methods can only relief the related symptoms of *** electro-acupuncture(EA)is a traditional Chinese medicine treatment combined the acupuncture and electrical stimulation and the treatment effect can also be controlled by transform the electrical ***,in this experiment,we carried out behavioral test,immunohistochemistry(IHC),and Western Blot(WB)after different period treatments to the model mice by electro-acupuncturing“Baihui”and“Shenshu”acupoints in APPt/PS1t double transgenic *** was found that the EA therapy can improve the ability of learning,memory and spatial exploration,and reduce the deposition of SPs in brain of AD model mice,and reduce the expressions of APP and BACE1,increase the expression of IDE *** results prompt that EA can effectively alleviate the pathological process of *** speculate that EA may play a comprehensive role in preventing the development of AD,considering the previous data.

关键词： Alzheimer’s disease Amyloid b-protein Electro-acupuncture Senile plaques Transgenic mice

Regulation of Excited-State Intramolecular Proton Transfer Process and Photophysical Properties for Benzoxazole Isothiocyanate Fluorescent Dyes by Changing Atomic Electronegativity

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Chinese Journal of Chemical Physics 2022年第2期35卷 331-337,I0011-I0025,I0003页

作者： Hongling Zhang Qingtong Liu yiying wang Zhe Tang Panwang Zhou Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Excited-state intramolecular proton transfer(ESIPT)is favored by researchers because of its unique optical ***,there are relatively few systematic studies on the effects of changing the electronegativity of atoms on the ESIPT process and photophysical ***,we selected a series of benzoxazole isothiocyanate fluorescent dyes(2-HOB,2-HSB,and 2-HSe B)by theoretical methods,and systematically studied the ESIPT process and photophysical properties by changing the electronegativity of chalcogen *** calculated bond angle,bond length,energy gap,and infrared spectrum analysis show that the order of the strength of intramolecular hydrogen bonding of the three molecules is 2-HOB2-HSB>2-HSe *** addition,the calculated electronic spectrum shows that as the atomic electronegativity decreases,the emission spectrum has a ***,this work will offer certain theoretical guidance for the synthesis and application of new dyes based on ESIPT properties.

关键词： Excited-state intramolecular proton transfer Photophysical properties Energy barrier Electronegativity

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水厂精准混凝投药实时控制系统的构建

给水排水 2023年第5期49卷 156-164页

作者：王艺颖深圳市科荣软件股份有限公司深圳518020

基于水厂运行大数据的采集,分别运用随机森林、XGBoost、BP神经网络3种人工智能算法,对混凝投药过程进行非线性建模和非线性预测,构建出水浊度预测模型并进行评估和对比,再以沉淀池出水浊度为控制目标进行最佳投药量求解。同时,模型通... 详细信息

基于水厂运行大数据的采集,分别运用随机森林、XGBoost、BP神经网络3种人工智能算法,对混凝投药过程进行非线性建模和非线性预测,构建出水浊度预测模型并进行评估和对比,再以沉淀池出水浊度为控制目标进行最佳投药量求解。同时,模型通过统计短时间隔流速计算混凝至出水之间的滞后时间,提高系统时滞计算的准确性。系统通过算法调用实现实时投药量计算,并与SCADA系统实现数据同步,最终通过SCADA下发指令实现对投药泵的控制。

关键词：混凝投药大数据人工智能水处理优化

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新时代中国区域经济协调发展的内涵解构与三重逻辑

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当代经济管理 2024年第11期46卷 75-86页

作者：王怡颖北京化工大学马克思主义学院北京100029

进入新时代以来,党中央实施了一系列致力于促进区域协调发展的国家战略,区域经济协调发展呈现出新的内涵特征,实现了区域繁荣和人的繁荣的内在协同、经济总量与经济结构的同步优化、空间中性与空间干预政策的动态均衡、国内市场与国际... 详细信息

进入新时代以来,党中央实施了一系列致力于促进区域协调发展的国家战略,区域经济协调发展呈现出新的内涵特征,实现了区域繁荣和人的繁荣的内在协同、经济总量与经济结构的同步优化、空间中性与空间干预政策的动态均衡、国内市场与国际市场的高效联动,区域经济发展融合性与互动性显著增强。立足于区域经济协调发展的外在特征抽象出区域经济发展的内在逻辑有利于构建中国特色社会主义区域经济发展。中国区域经济格局实际是党领导下的国家、竞争性地方政府与市场机制三重要素配置主体力量博弈的现实映射,三重路径相互嵌合、互为交织,最终构筑了区域经济协调发展的稳态均衡。新时代下为实现区域经济高质量发展,党中央应积极构建“三位一体”的要素配置体系,以新质生产力培育为基点提升区域内要素配置效率水平,促进区域产业结构优化升级。

关键词：新时代区域经济协调发展内涵逻辑

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要素错配的马克思主义政治经济学分析

当代经济管理 2022年第2期44卷 10-20页

作者：王怡颖北京大学马克思主义学院北京100871

不同于西方经济学对要素错配的分析,以马克思政治经济学为出发点,重新阐释要素错配理论逻辑,解释要素错配对社会经济发展不平衡影响的作用机理,并在此基础上揭示中国特色社会主义市场经济体制下要素错配界定、形成及其表现。主流经济学... 详细信息

不同于西方经济学对要素错配的分析,以马克思政治经济学为出发点,重新阐释要素错配理论逻辑,解释要素错配对社会经济发展不平衡影响的作用机理,并在此基础上揭示中国特色社会主义市场经济体制下要素错配界定、形成及其表现。主流经济学对要素错配的阐释过于狭隘,仅仅依靠市场并不能实现要素的最优配置,单纯的市场经济同样会产生要素错配。要素错配作为资本主义制度下特定生产关系的产物,在经济发展传导机制中发挥中介作用。一方面,资本主义制度下以资本为逻辑的生产往往驱使生产要素打破经济平衡状态,产生要素错配;另一方面,要素错配将嵌入社会再生产环节之中,通过作用于生产过程影响经济的平衡发展。新时代中国特色社会主义市场经济条件下的要素错配的界定具有双重规定性。因此,要素错配的解决一方面依赖于构建政府与市场良性互动机制,实现两者的优势互补,另一方面需要破除制度性壁垒,为要素自由流动提供制度保障。

关键词：要素错配马克思主义政治经济学政府市场

中国对“一带一路”沿线国家农业机械产品贸易潜力研究

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中国农机化学报 2023年第7期44卷 244-253页

作者：佟光霁王艺颖东北林业大学经济管理学院哈尔滨市150040

随着加入“一带一路”倡议的国家增多,我国与“一带一路”沿线国家的农业机械产品出口贸易额也稳步增长。选取中国与“一带一路”沿线121个国家的农机产品出口贸易数据,通过构建时变随机前沿引力模型测算我国对“一带一路”国家的农机... 详细信息

随着加入“一带一路”倡议的国家增多,我国与“一带一路”沿线国家的农业机械产品出口贸易额也稳步增长。选取中国与“一带一路”沿线121个国家的农机产品出口贸易数据,通过构建时变随机前沿引力模型测算我国对“一带一路”国家的农机产品贸易效率和可拓展空间,并通过显示性比较劣势计算产品进口依赖度,根据这两项指标分析中国对“一带一路”沿线国家农机产品出口的未来前景。研究结果表明,国家经济规模、人口规模、国家地理距离和共同语言均对农机产品贸易有显著影响,而通信和物流基础设施质量以及双边贸易协定会显著提高贸易效率。非洲、亚洲和北美洲的贸易可拓展潜力较高,中国与“一带一路”沿线国家未来的贸易前景依然广阔。

关键词： “一带一路” 农业机械产品贸易贸易潜力随机前沿引力模型