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Elasto-Plastic Test of Q235 Steel Bending Beam With Cracking Resistance

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Journal of Iron and Steel Research(International) 2013年第11期20卷 57-66页

作者： wang Li-min FENG Ying CHEN Fan-xiu wang Hai-ying wang dong-xu Science School Qingdao Technological University Institute of Mechanics Chinese Academy of Sciences

More than 30 bending beams with rectangular cross-section and different thicknesses and heights were pre- pared from Q295 steel. The specimen dimensions were about 240 mm （length） × 60 mm （height） ×70 mm （thick ness）. Flaws were cut along its middle line with a wire cutter, with lengths ranging from 6 to 35 mm. Each specimen was tested with three-point bend loading, and a process curve was obtained between load and the displacement of the loading point, in order to analyze the fracture process when opening the crack. A deformation near the prefabricated crack was observed in the testing period, and the variation of the fracture characteristic parameters was analyzed for different sizes. For a comprehensive understanding of carbon steel fracture resistance behavior, its elasticity and plas- ticity were established by determining its Young＇s modulus and Poisson＇s ratio with an optical strain gauge. This gauge was also used for the loading process test. It was found that the fracture toughness varied with the dimensions, and the toughness of the elastic limit loading was almost constant. Using the relationship of crack resistance stress intensity factor and fracture criterion, the bearing capacity of the material structure could be estimated, which shows a good agreement with the experimental test data.

关键词： elasto-plastic property fracture toughness elastic limit loading bearing capacity cracking resistance Q235 steel bending beam

小应变土体硬化模型参数的敏感性分析及确定方法

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科学技术与工程 2024年第15期24卷 6366-6376页

作者：董鑫周峰朱锐王旭东曾丽媛南京工业大学交通运输工程学院南京211816

小应变土体硬化(hardening soil model with small strain stiffness,HSS)模型能够反映土体小应变阶段的非线性特性和应力相关性,在深基坑工程领域已被广泛应用。但由于模型参数众多,目前对参数确定方法尚缺乏系统研究。分析了HSS模型... 详细信息

小应变土体硬化(hardening soil model with small strain stiffness,HSS)模型能够反映土体小应变阶段的非线性特性和应力相关性,在深基坑工程领域已被广泛应用。但由于模型参数众多,目前对参数确定方法尚缺乏系统研究。分析了HSS模型各参数的意义及常规确定方法,采用数值模拟方法开展了HSS模型参数的敏感性分析,基于统计的大量研究成果,建立了土体参数与孔隙比之间的非线性关系,进一步通过2处深基坑工程的变形分析进行验证。结果表明:在基坑数值分析中,参考动剪切模量G_(0)^(ref)的敏感性最高,参考切线模量E_(oed)^(ref)的敏感性最低,建立的非线性关系能够较好地反映土体模量与孔隙比的相关性,围护结构侧移的计算值及实测值较为吻合,验证了提出的参数确定方法的适用性,可为相关工程提供参考。

关键词：基坑工程 HSS模型小应变特性敏感性分析参数确定

长江流域安庆段浅层地下水水化学特征及控制因素

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环境科学 2024年第3期45卷 1525-1538页

作者：刘海宋阳李迎春魏伟赵国红王旭东黄健敏安徽省公益性地质调查管理中心合肥230091 四川农业大学建筑与城乡规划学院成都611830

浅层地下水为安庆市居民生活用水和工农业生产用水的主要水源,是维持社会经济可持续发展和区域生态环境的重要基础保障.为深入研究安庆市浅层地下水的水化学特征及控制因素,采集了196组浅层地下水水样,综合运用Piper三线图、Gibbs图、... 详细信息

浅层地下水为安庆市居民生活用水和工农业生产用水的主要水源,是维持社会经济可持续发展和区域生态环境的重要基础保障.为深入研究安庆市浅层地下水的水化学特征及控制因素,采集了196组浅层地下水水样,综合运用Piper三线图、Gibbs图、离子比值和数理统计方法对安庆市地下水的水化学特征及控制因素进行研究,定量评估不同来源对地下水水化学组分的贡献.结果表明,安庆市浅层地下水呈弱碱性,pH值在5.84~8.38,均值为7.21;ρ(TDS)介于47~1 620 mg·L^(-1),均值为324.21mg·L^(-1),阴阳离子主要以HCO_(3)^(-)和Ca^(2+)为主,水化学类型为HCO_(3)^(-)Ca型.地下水水化学组分受岩石风化溶滤作用、阳离子交替吸附作用、矿物溶解和沉淀以及人类活动综合影响.Ca^(2+)、Mg^(2+)和HCO_(3)^(-)主要来源于碳酸盐岩和硅酸盐岩的风化溶解作用,Na^(+)、Cl^(-)和SO_(4)^(2-)受工业活动和生活污水的排放、K^(+)和NO_(3)^(-)受农业活动的影响.APCS-MLR受体模型分析进一步揭示地下水水化学组分主要有地质因子、工业因子、农业因子和未知源这4种来源,其贡献率分别为45.35%、14.19%、25.38%和15.08%.地质因子是浅层地下水水化学组分的重要来源,人类活动则加剧了地下水水化学的演变.

关键词：浅层地下水水化学特征水岩作用控制因素安庆市

A Formula for Khovanov Type Link Homology of Pretzel Knots

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Communications in Mathematical Research 2016年第3期32卷 198-206页

作者： Zhang Mei-li Lei Feng-chun Li Feng-ling wang dong-xu School of Mathematical Sciences Dalian University of Technology Department of Basis Dalian Naval Academy Mathematics Department Dongbei University of Finance and Economics

Khovanov type homology is a generalization of Khovanov homology.The main result of this paper is to give a recursive formula for Khovanov type homology of pretzel knots P(-n,-m, m). The computations reveal that the rank of the homology of pretzel knots is an invariant of n. The proof is based on a "shortcut" and two lemmas that recursively reduce the computational complexity of Khovanov type homology.

关键词： pretzel knot Khovanov type homology Frobenius algebra TQFT

盐析辅助液液萃取结合气相色谱-质谱法测定酱油中4种氯丙醇

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食品安全质量检测学报 2024年第11期15卷 182-188页

作者：曾坤王东旭王新财谷贵章湖州市食品药品检验研究院

目的建立盐析辅助液液萃取结合气相色谱-质谱法测定酱油中1,3-二氯-2-丙醇、2,3-二氯-1-丙醇、3-氯-1,2-丙二醇和2-氯-1,3-丙二醇的分析方法。方法以D5-3-氯-1,2-丙二醇为内标物,酱油样品经乙腈提取,氯化钠盐析分层,七氟丁酰基咪唑衍... 详细信息

目的建立盐析辅助液液萃取结合气相色谱-质谱法测定酱油中1,3-二氯-2-丙醇、2,3-二氯-1-丙醇、3-氯-1,2-丙二醇和2-氯-1,3-丙二醇的分析方法。方法以D5-3-氯-1,2-丙二醇为内标物,酱油样品经乙腈提取,氯化钠盐析分层,七氟丁酰基咪唑衍生,HP-5MS毛细管柱(30m×0.25mm,0.25μm)分离,采用气相色谱-质谱法的选择离子监测模式进行测定。实验考察了盐析助剂、萃取溶剂对4种氯丙醇萃取效率的影响。结果最优实验条件下,4种氯丙醇在0.006～0.120mg/kg范围内线性关系良好,且相关系数都大于0.999,检出限为0.002 mg/kg,定量限为0.006 mg/kg。在0.02、0.05、0.10 mg/kg的加标水平下, 4种氯丙醇的加标回收率为70.2%～103.5%,相对标准偏差为1.6%～5.5%。结论本方法快速、简便、节省溶剂,适用于酱油中氯丙醇的快速定性、定量分析。

关键词：酱油氯丙醇盐析辅助液液萃取气相色谱-质谱法

miR-26a对骨肉瘤发生转移及治疗作用的研究进展

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中国骨与关节杂志 2024年第5期13卷 396-400页

作者：李广渝王旭东李明河北医科大学第二医院骨科石家庄050000

骨肉瘤是最常见的骨恶性肿瘤,儿童和青少年发病率高[1],好发于四肢长骨的干骺端,很少出现在中轴骨骼和其它部位[2]。局限性骨肉瘤患者5年生存率达到60%~70%,但发生骨转移的患者5年生存率大约只有20%[3]。骨肉瘤的常规治疗包括手术、新... 详细信息

骨肉瘤是最常见的骨恶性肿瘤,儿童和青少年发病率高[1],好发于四肢长骨的干骺端,很少出现在中轴骨骼和其它部位[2]。局限性骨肉瘤患者5年生存率达到60%~70%,但发生骨转移的患者5年生存率大约只有20%[3]。骨肉瘤的常规治疗包括手术、新辅助治疗和放化疗[4],目前临床最常用手术联合辅助化疗[5]。由于骨肉瘤患者对化疗药物的耐药性、复发和远处转移等影响使得骨肉瘤患者的预后仍然很差[6]。因此,探索骨肉瘤发生和发展机制,对骨肉瘤治疗和改善患者预后具有重大意义。

关键词：骨肉瘤微RNA 抗药性肿瘤 miR-26a 综述

磷石膏改性植生基质中有害物质的固化与污染控制

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广州化工 2024年第8期52卷 75-78页

作者：袁永辉王国胥琳琳李昌亮王旭东中海建筑有限公司广东深圳518052

为了研究改良剂对磷石膏基质的改良效果,在磷石膏植生基质中添加两种不同配比的改良剂,并在基质播种黑麦草,通过对基质的物理性质、黑麦草的生长指标以及渗滤液的部分指标进行测定并分析,探究不同配比改良剂的改良效果。结果表明,在基... 详细信息

为了研究改良剂对磷石膏基质的改良效果,在磷石膏植生基质中添加两种不同配比的改良剂,并在基质播种黑麦草,通过对基质的物理性质、黑麦草的生长指标以及渗滤液的部分指标进行测定并分析,探究不同配比改良剂的改良效果。结果表明,在基质的物理性质的改良效果上,T_(1)组的改良效果比T_(2)组的效果好;在对黑麦草生长影响上,经过改良后的基质更利于黑麦草生长,且T_(2)组效果好于T_(1)。基质的渗滤液实验结果表明,添加改良剂对基质pH值的提高和对基质的固定效果比较显著,pH的改良效果上T_(1)高于T_(2),对基质的固定T_(2)的效果略好于T_(1),在EC上添加改良剂的效果不明显。三组基质的渗滤液中Fe、Mn、Cu、Zn、Pb含量都呈现显著下降趋势,但改良基质中的重金属浓度下降速度更快。本研究结果可为磷石膏基质进行改良提供参考。

关键词：磷石膏基质改良黑麦草重金属

Polarizable Additive with Intermediate Chelation Strength for Stable Aqueous Zinc‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 41-55页

作者： Yuting Xia Rongao Tong Jingxi Zhang Mingjie xu Gang Shao Hailong wang Yanhao dong Chang‑An wang State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084People’s Republic of China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanPeople’s Republic of China

Aqueous zinc-ion batteries are promising due to inherent safety,low cost,low toxicity,and high volumetric capacity.However,issues of dendrites and side reactions between zinc metal anode and the electrolyte need to be solved for extended storage and cycle life.Here,we proposed that an electrolyte additive with an intermediate chelation strength of zinc ion—strong enough to exclude water molecules from the zinc metal-electrolyte interface and not too strong to cause a significant energy barrier for zinc ion dissociation—can benefit the electrochemical stability by suppressing hydrogen evolution reaction,overpotential growth,and den-drite formation.Penta-sodium diethylene-triaminepentaacetic acid salt was selected for such a purpose.It has a suitable chelating ability in aqueous solutions to adjust solvation sheath and can be readily polarized under electrical loading conditions to further improve the passivation.Zn||Zn symmetric cells can be stably operated over 3500 h at 1 mA cm^(-2).Zn||NH4V4O10 full cells with the additive show great cycling stability with 84.6%capacity retention after 500 cycles at 1 A g^(-1).Since the additive not only reduces H2 evolution and corrosion but also modifies Zn2+diffusion and deposition,highlyreversible Zn electrodes can be achieved as verified by the experimental results.Our work offers a practical approach to the logical design of reliable electrolytes for high-performance aqueous batteries.

关键词： Aqueous zinc-ion batteries Electrolyte additives DTPA-Na Chelation strength

Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

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Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： Shiyu Jia Cheng wang Wenlong xu dong Ma Fangfang Qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military conflicts.Although strong shock wave is lethal to the human body,weak shock wave can cause many more lasting consequences.To investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual protection.Experimental results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not damaged.The shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic characteristics.The overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample thickness.For the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three materials.In this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are designed.Different layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective performance.Within the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm respectively.The overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of single-layer polyurea and polyurethane foam with

关键词： Free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites