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Dynamic Resistance and Energy Absorption of Sandwich Beam via a Micro-Topology Optimization

Chinese Journal of Mechanical Engineering 2024年第4期 159-175页

作者： Shiqiang Li yuwei Li Xiaomin Ma Jianguang Fang Zhifang Liu Zhihua Wang Institute of Applied Mechanics Taiyuan University of Technology Shanxi Key Laboratory of Material Strength and Structural Impact Taiyuan University of Technology School of Civil and Environmental Engineering University of Technology Sydney

The current research of sandwich structures under dynamic loading mainly focus on the response characteristic of structure. The micro-topology of core layers would sufficiently influence the property of sandwich ***, the micro deformation and topology mechanism of structural deformation and energy absorption are unclear. In this paper, based on the bi-directional evolutionary structural optimization method and periodic base cell(PBC) technology, a topology optimization frame work is proposed to optimize the core layer of sandwich *** objective of the present optimization problem is to maximize shear stiffness of PBC with a volume *** effects of the volume fraction, filter radius, and initial PBC aspect ratio on the micro-topology of the core were discussed. The dynamic response process, core compression, and energy absorption capacity of the sandwich beams under blast impact loading were analyzed by the finite element method. The results demonstrated that the overpressure action stage was coupled with the core compression stage. Under the same loading and mass per unit area,the sandwich beam with a 20% volume fraction core layer had the best blast resistance. The filter radius has a slight effect on the shear stiffness and blast resistances of the sandwich beams. But increasing the filter radius could slightly improve the bending stiffness. Upon changing the initial PBC aspect ratio, there are three ways for PBC evolution: The first is to change the angle between the adjacent bars, the second is to further form holes in the bars, and the third is to combine the first two ways. However, not all three ways can improve the energy absorption capacity of the structure. Changing the aspect ratio of the PBC arbitrarily may lead to worse results. More studies are necessary for further detailed optimization. This research proposes a new topology sandwich beam structure by micro-topology optimization, which has sufficient shear stiffness. The mi

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沉积物中Pb和Cd对泥鳅的毒性效应及其基准阈值的验证

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环境科学研究 2015年第7期28卷 1078-1084页

作者：韩雨薇钟文珏张彦峰强沥文祝凌燕南开大学环境污染过程与基准教育部重点实验室天津市生态环境修复与防治重点实验室南开大学环境科学与工程学院天津300071

为探讨沉积物中AVS(acid volatile sulfide,酸挥发性硫化物)和SEM(simultaneously extracted metals,同时提取金属)对重金属生物有效性和基准验证的影响,以泥鳅为受试生物,以死亡率、鳃部渗血率和体质量变化为测试终点,研究了沉积物和... 详细信息

为探讨沉积物中AVS(acid volatile sulfide,酸挥发性硫化物)和SEM(simultaneously extracted metals,同时提取金属)对重金属生物有效性和基准验证的影响,以泥鳅为受试生物,以死亡率、鳃部渗血率和体质量变化为测试终点,研究了沉积物和上覆水中重金属Pb、Cd对底栖生物的毒性效应,并对文献中Pb、Cd沉积物基准阈值进行了验证.结果表明:沉积物中Pb、Cd对泥鳅21d的LC50(半数致死浓度)分别为391、37.0 mg/kg;上覆水中ρ(Pb2+)和ρ(Cd2+)较低,对生物毒性效应贡献可以忽略.经验证,Pb和Cd的TEL(threshold effect level,临界效应浓度)和PEL(probable effect level,必然效应浓度)基本符合其所代表的意义,Pb、Cd加标浓度(以w计)低于其对应的TEL时不具有毒性,高于其对应的PEL时具有明显毒性,介于二者之间时毒性不确定.SEM/AVS(物质的量比)和生物死亡率有明显的相关性,当该比值大于1.00时,重金属对泥鳅有明显的毒性效应.

关键词：重金属生物效应沉积物质量基准酸挥发性硫化物

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The Classic Shaping of Typical Female Images by Mulan Motif in Historical Times-Historical Review and Textual Sorting of the Motif

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Cultural and Religious Studies 2024年第5期12卷 320-323页

作者： XIAO yuwei ZhanG Pei Beijing Institute of Graphic Communication BeijingChina

The image of Mulan is well known to the public as an important symbol in the dissemination of Chinese excellent traditional *** paper aims to summarise the mother-title from traditional canonical texts,to explore the content and value of sustainable IP development,and to study a large number of derivatives with the image of Mulan as the mother-title,based on the wide circulation of the prototype of the mother-title“The Poem of Mulan”(木兰辞)and the positive values conveyed by the *** the processing and imagination of scholars and writers on the mother text in the past generations,the image of Mulan has gradually formed a relatively stable cultural communication theme in the process of dissemination in China’s historical period,and many adaptations with international influence based on the mother title of Mulan have emerged in the foreign dissemination,so through the combing and summarisation of the textual works of various periods both at home and abroad,we will dig out the textual transmission of the mother title of Mulan,which is representative of the mother title of China’s excellent traditional culture,and the development of the Chinese spiritual *** Development of the Chinese Spiritual *** paper adopts research methods such as documentary evidence method and discourse analysis to show the textual flow of Mulan’s parent theme in a more diversified form.

关键词： Mulan motifs feminine power textual transmission literature review identity

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GIS空间分析中的Kriging插值法在吉林省乡镇规划中的应用

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国土资源信息化 2010年第3期 17-20页

作者：韩玉薇张娇吉林省国土资源信息中心长春市130042

为了适应改革开放和经济发展的需要,吉林省的行政区划在近年来不断有大的变动,本文所采取的是利用GIS空间分析中的kriging插值法来进行吉林省乡镇的规划,使乡镇的规划更具有直观性、科学性。

关键词：行政区划空间分析 kriging插值

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A novel semi-dominant allele of the transmembrane NAC transcription factor ZmNTL2 reduces the size of multiple maize organs

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The Crop Journal 2024年第3期12卷 676-687页

作者： Chuan Li Yun Bai yuwei Hou Siyu Wang Yue Xin Tao Yu Jing Wang Xiaowei Liu Hongyang Yi Chao Xia Hai Lan Moju Cao State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Maize Research InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina Jilin Engineering Research Center for Crop Biotechnology Breeding College of Plant ScienceJilin UniversityChangchun 130012JilinChina

Maize plant architecture influences planting density and,in turn,grain *** of the plant architecture-related traits can be described as organ *** describe a miniature maize mutant,Tiny plant 4(Tip4),which exhibits reduced size of multiple organs and exhibits a semi-dominant monofactorial inheritance *** cloning confirmed that a 4-bp deletion in the NAC TF with transmembrane motif 1-Like(NTL)gene ZmNTL2,denoted as ZmNTL2^(Δ),confers the Tip4 ***-PCR showed that ZmNTL2 was expressed in all tested ***2 functions as a transcriptional activator and is located in both the nucleus and *** mutation does not affect the mRNA abundance of ZmNTL2 locus,but it does result in the loss of transmembrane domain and confines the ZmNTL2^(Δ)protein to the *** out ZmNTL2 has no effect on maize organ size development,indicating that the 4-bp deletion might be a gain-of-function mutation in organ size *** transcriptome sequencing with cytokinin and auxin content determination suggests that the decreased organ size may be possibly mediated by changes in hormone homeostasis.

关键词： Organ size c-ray mutagenesis Membrane-bound NAC TF Hormone homeostasis Maize

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沉积物中五氯酚对底栖生物的急慢性毒性效应

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生态毒理学报 2015年第1期10卷 297-304页

作者：钟文珏张瑜韩雨薇祝凌燕天津城市生态环境修复与污染防治重点实验室教育部环境污染过程与基准重点实验室南开大学环境科学与工程学院天津300071

以淡水底栖动物花翅羽摇蚊幼虫和淡水单孔蚓为研究对象,研究了沉积物中五氯酚对底栖生物的急慢性毒性效应。五氯酚对花翅羽摇蚊幼虫96 h及10 d的半数致死浓度(LC50)分别为20.6 mg·kg-1和12.5 mg·kg-1,28 d羽化半数抑制浓度(EC50)为0.7... 详细信息

以淡水底栖动物花翅羽摇蚊幼虫和淡水单孔蚓为研究对象,研究了沉积物中五氯酚对底栖生物的急慢性毒性效应。五氯酚对花翅羽摇蚊幼虫96 h及10 d的半数致死浓度(LC50)分别为20.6 mg·kg-1和12.5 mg·kg-1,28 d羽化半数抑制浓度(EC50)为0.79 mg·kg-1。沉积物中五氯酚对花翅羽摇蚊幼虫的羽化具有延滞作用,而且对雌性摇蚊羽化的延滞作用大于雄性,最终导致羽化摇蚊的性别失衡。淡水单孔蚓对五氯酚的耐受力较摇蚊幼虫强。五氯酚对淡水单孔蚓的96 h及14 d的LC50分别为37.6 mg·kg-1和20.2 mg·kg-1,对淡水单孔蚓21 d生长抑制的EC50为1.39 mg·kg-1。研究结果对推导五氯酚沉积物质量基准和进行沉积物生态风险评价提供依据。

关键词：五氯酚底栖生物急性毒性慢性毒性沉积物环境质量基准

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热水解预处理对剩余污泥可生物降解性的影响

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环境工程学报 2016年第8期10卷 4445-4450页

作者：刘阳曾薇韩玉伟马文锦彭永臻北京工业大学北京市水质科学与水环境恢复工程重点实验室北京市污水脱氮除磷处理与过程控制工程技术研究中心北京100124 北京工业大学建筑工程学院北京100124 北京排水集团北京100044

针对剩余污泥可生物降解性差的问题,以热水解作为预处理手段,研究了其对剩余污泥可生化性的提高作用。热水解在175℃,0.6~0.8 MPa条件下进行30 min。结果表明,剩余污泥经热水解后,水解率可达48%,挥发性脂肪酸浓度提高7~8倍,COD当量平均7... 详细信息

针对剩余污泥可生物降解性差的问题,以热水解作为预处理手段,研究了其对剩余污泥可生化性的提高作用。热水解在175℃,0.6~0.8 MPa条件下进行30 min。结果表明,剩余污泥经热水解后,水解率可达48%,挥发性脂肪酸浓度提高7~8倍,COD当量平均7 800 mg·L^(-1),生化产甲烷潜力提高43%左右。厌氧消化实验中,组合有热水解预处理的温度两相工艺和中温单相工艺容积产甲烷率为0.760和0.719 L·(L·d)-1,甲烷产率为0.288 L·g-1和0.255 L·g-1,均显著高于传统中温单相工艺的0.376 L·(L·d)-1和0.138 L·g-1。组合工艺的挥发性有机物去除率为48.64%和46.51%,比传统工艺高8%~11%。比甲烷产率提高约50%,表明这些被转化的有机物较传统工艺中被转化者产能更多。工艺对比发现,虽然热水解联合温度两相工艺效率最高,但热水解联合中温单相工艺几乎同样高效且工艺更简单实用。

关键词：热水解剩余污泥可生物降解性厌氧消化

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虎杖苷通过抑制内质网应激改善蛛网膜下腔出血后早期脑损伤

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中华实验外科杂志 2023年第9期40卷 1720-1722页

作者：韩雨薇梁国标李晓明北部战区总医院神经外科沈阳110016

目的探讨虎杖苷(PD)对蛛网膜下腔出血(SAH)后内质网应激的作用及其机制。方法腹腔注射给予小鼠不同剂量(10、20、30 mg/kg)的PD。检测Sham、SAH、SAH+vehicle、SAH+PD 10 mg/kg、SAH+PD 20 mg/kg、SAH+PD 30 mg/kg各组蛛网膜下腔出血量... 详细信息

目的探讨虎杖苷(PD)对蛛网膜下腔出血(SAH)后内质网应激的作用及其机制。方法腹腔注射给予小鼠不同剂量(10、20、30 mg/kg)的PD。检测Sham、SAH、SAH+vehicle、SAH+PD 10 mg/kg、SAH+PD 20 mg/kg、SAH+PD 30 mg/kg各组蛛网膜下腔出血量、神经功能评分、脑含水量和伊文斯蓝渗出。采用蛋白质免疫印迹法检测SIRT1,内质网应激相关标志物和凋亡相关蛋白的表达水平。同时采用免疫荧光染色和缺口末端标记法(TUNEL)染色评价神经元细胞凋亡。组间比较采用单因素方差分析。结果PD组SAH评分、脑水肿、伊文斯蓝渗出量低于SAH组[(5.75±0.97)分比(12.25±2.03)分、(74.86±7.94)%比(82.24±5.41)%、(1.11±0.21)μg/g比(1.66±0.24)μg/g,(t=10.83、6.38、6.52,均P<0.01)]。PD组沉默信息调节因子2相关酶1(SIRT1)表达高于SAH组(3.96±0.56比1.00±0.04,t=5.80,P<0.01)。结论PD介导SIRT1抑制内质网应激改善蛛网膜下腔出血后的早期脑损伤。

关键词：虎杖苷蛛网膜下腔出血内质网应激早期脑损伤

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Building Metaverse Digital Humanities Labs:Strategies and Challenges in Higher Education

IJLAI Transactions on Science and Engineering

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IJLAI Transactions on Science and Engineering 2024年第2期2卷 36-44页

作者： Xiaoxi Tian yuwei Liu Kuangyi He Shenyang Jianzhu University Shenyang 110159China

The integration of metaverse technologies within the academic sphere is redefining the landscape of digital humanities research and *** study examines the current state and future prospects of metaverse digital humanities laboratories in higher education institutions,highlighting their importance and the challenges they *** research underscores the significance of these laboratories in fostering interdisciplinary collaboration,enhancing educational experiences,and promoting cultural preservation through digital *** metaverse digital humanities laboratories are seen as crucial platforms for innovation,providing immersive environments that facilitate the application of advanced digital tools in humanities *** study identifies key challenges,including the need for robust hardware infrastructure,the complexity of technology integration,data management concerns,and the necessity for ethical frameworks that address privacy and intellectual property *** also emphasizes the importance of user experience,interdisciplinary collaboration,and the development of a comprehensive talent cultivation system that aligns with the digital *** for the construction and development of these laboratories are proposed,such as accelerating metaverse infrastructure development,promoting the transformation of traditional digital humanities laboratories,and establishing mechanisms for data protection and resource *** research also calls for the enhancement of user experiences through personalized services and the cultivation of talent through interdisciplinary educational *** conclusion,the metaverse digital humanities laboratories represent a strategic frontier in academic innovation,offering transformative potential for research and education in the *** study provides a roadmap for the development of these laboratories,suggesting a comprehensive approach that addresses technological,pedagogical,ethical,and finan

关键词： Metaverse Digital humanities Higher education Virtual reality Augmented reality Educational innovation Cultural preservation

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Robust,self-adhesive,and low-contact impedance polyvinyl alcohol/polyacrylamide dual-network hydrogel semidry electrode for biopotential signal acquisition

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SmartMat 2024年第2期5卷 67-82页

作者： Guangli Li Ying Liu yuwei Chen Yonghui Xia Xiaoman Qi Xuan Wan Yuan Jin Jun Liu Quanguo He Kanghua Li Jianxin Tang Hunan Key Laboratory of Biomedical Nanomaterials and Devices College of Life Sciences and ChemistryHunan University of TechnologyZhuzhouChina Department of Neurology Zhuzhou People's HospitalZhuzhouChina Zhuzhou Institute for Food and Drug Control ZhuzhouChina

Herein,we fabricated a flexible semidry electrode with excellent mechanical performance,satisfactory self-adhesiveness,and low-contact impedance using physical/chemical crosslinked polyvinyl alcohol/polyacrylamide dual-network hydrogels(PVA/PAM DNHs)as an efficient saline *** resultant PVA/PAM DNHs showed admirable adhesive and compliance to the hairy scalp,facilitating the establishment of a robust electrode/skin interface for biopotential signal ***,the PVA/PAM DNHs steadily released trace saline onto the scalp to achieve the minimized potential drift(1.47±0.39 mV/min)and low electrode–scalp impedance(18.2±8.9 kΩ@10 Hz).More importantly,the application feasibility of real-world brain−computer interfaces(BCIs)was preliminarily validated by 10 participants using two classic BCI *** mean temporal cross-correlation coefficients between the semidry and wet electrodes in the eyes open/closed and the N200 speller paradigms are 0.919±0.054 and 0.912±0.050,*** electrodes demonstrate anticipated neuroelectrophysiological responses with similar *** semidry electrode could also effectively capture robust P-QRS-T peaks during electrocardiogram *** their outstanding advantages of fast setup,user-friendliness,and robust signals,the proposed PVA/PAM DNH-based electrode is a promising alternative to wet electrodes in biopotential signal acquisition.

关键词： brain-computer interface dual-network hydrogel electrocardiogram signals electroencephalography signals semidry electrode

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