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Flexural and longitudinal shear performance of precast lightweight steel-ultra-high performance concrete composite beam

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 704-721页

作者： Ze MO Jiangrui QIU Hanbin XU Lanlan XU yuqing hu Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education School of Civil EngineeringSoutheast UniversityNanjing 211189China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China School of Civil Engineering Jiangsu Open UniversityNanjing 210036China

In this study,the flexural and longitudinal shear performances of two types of precast lightweight steel–ultra-high performance concrete(UHPC)composite beams are investigated,where a cluster UHPC slab(CUS)and a normal UHPC slab(NUS)are connected to a steel beam using headed studs through discontinuous shear pockets and full-length shear pockets,*** show that the longitudinal shear force of the CUS is greater than that of the NUS,whereas the interfacial slip of the former is *** to its better integrity,the CUS exhibits greater flexural stiffness and a higher ultimate bearing capacity than the *** further optimize the design parameters of the CUS,a parametric study is conducted to investigate their effects on the flexural and longitudinal shear *** square shear pocket is shown to be more applicable for the CUS,as the optimal spacing between two shear pockets is 650 ***,a design method for transverse reinforcement is proposed;the transverse reinforcement is used to withstand the splitting force caused by studs in the shear pocket and prevent the UHPC slab from *** to calculation results,the transverse reinforcement can be canceled when the compressive strength of UHPC is 150 MPa and the volume fraction of steel fiber exceeds 2.0%.

关键词： precast steel-UHPC composite beam flexural performance longitudinal shear performance parametric study transverse reinforcement ratio

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煤矸石综合利用技术现状与标准体系研究

中国矿业 2024年第7期33卷 89-98页

作者：潘硕胡雨晴王海燕于家琳刘青松中国环境科学研究院北京100012 中国地质大学(北京)水资源与环境学院北京100083 国家黄河流域生态保护和高质量发展联合研究中心北京100012

煤矸石是煤炭开采和选煤过程中产生的主要废弃物,在我国西北地区产生量巨大。由于缺乏有效的综合利用,大量煤矸石无法消纳,只能就地堆存,占用了大量土地资源的同时也带来环境污染和生态破坏的风险,因此,探索建立煤矸石的综合利用技术体... 详细信息

煤矸石是煤炭开采和选煤过程中产生的主要废弃物,在我国西北地区产生量巨大。由于缺乏有效的综合利用,大量煤矸石无法消纳,只能就地堆存,占用了大量土地资源的同时也带来环境污染和生态破坏的风险,因此,探索建立煤矸石的综合利用技术体系,并配套完善的技术标准体系至关重要。本文对我国近十年来煤矸石产生和利用情况进行分析,并调研当前国内煤矸石综合利用技术现状和标准体系,分析总结出制约我国煤矸石综合利用技术发展存在的问题,包括无法支撑大规模消纳需求、缺乏技术标准体系支撑、技术区域特征明显、不利于复制推广等;针对技术推广过程中缺乏技术规范及标准的情况,总结当前煤矸石综合利用领域标准现状,提出当前标准体系中存在的问题,包括缺乏污染防控标准体系、缺乏综合利用技术规范等。通过上述分析,为煤矸石综合利用行业提出相应的建议,旨在为煤矸石综合利用技术体系的发展方向和标准体系的完善提供参考和借鉴,以实现煤矸石更加高效、安全和环保的综合利用。

关键词：煤矸石环境管理综合利用政策法规环境标准

新旧混凝土界面双面直剪性能尺寸效应试验研究

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河北工程大学学报（自然科学版） 2024年第1期41卷 1-8页

作者：吴二军刘谦胡雨晴河海大学土木与交通学院江苏南京210098 中国能源建设集团浙江省电力设计院有限公司浙江杭州310012

以界面处理方式、横向约束形式、混凝土强度、界面尺寸为变量,开展了8组50个新旧混凝土界面试件双面直剪试验研究,得到界面受剪破坏形态和抗剪强度-滑移曲线,分析界面抗剪强度的尺寸效应规律,拟合得到新旧混凝土双面直剪试件极限应力尺... 详细信息

以界面处理方式、横向约束形式、混凝土强度、界面尺寸为变量,开展了8组50个新旧混凝土界面试件双面直剪试验研究,得到界面受剪破坏形态和抗剪强度-滑移曲线,分析界面抗剪强度的尺寸效应规律,拟合得到新旧混凝土双面直剪试件极限应力尺寸效应的换算系数,建立受剪承载力计算表达式。结果表明:在剪力作用方向上,新旧混凝土界面受剪极限应力存在明显的随界面高度增加而降低的尺寸效应现象;开裂应力、裂通应力以及滑移的尺寸效应不明显;施加横向约束可提升界面裂通应力和极限应力;施加预压应力可显著提升试件的裂通应力,并有效限制试件的极限滑移。无横向约束条件下,凿毛形式对极限应力影响显著,相比整浇混凝土试件,机械凿毛的同强度新旧混凝土双面直剪极限应力减少至整浇试件的0.22以下,而人工凿毛试件的折减系数在0.34~0.37之间。有横向约束条件下,同凿毛粗糙界面相比,规则齿槽试件的开裂应力、裂通应力以及滑移表现优势突出;约束下强度折减系数提高到无约束同等条件试件的2~2.5倍以上,最大可达到整浇试件强度的0.97倍。新旧混凝土强度提高可增加试件裂通应力和极限应力,但提升幅度有限。

关键词：新旧混凝土界面受剪性能尺寸效应双面直剪

Digital twin for healthy indoor environment:A vision for the post-pandemic era

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Frontiers of Engineering Management 2023年第2期10卷 300-318页

作者： Jiannan CAI Jianli CHEN yuqing hu Shuai LI Qiang HE School of Civil&Environmental Engineering and Construction ManagementThe University of Texas at San AntonioSan AntonioTX 78249USA Department of Civil&Environmental Engineering The University of UtahSalt Lake CityUT 84112USA Department of Architectural Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Civil and Environmental Engineering The University of TennesseeKnoxvilleKnoxvilleTN 37996USA

Indoor environment has significant impacts on human health as people spend 90%of their time *** COVID-19 pandemic and the increased public health awareness have further elevated the urgency for cultivating and maintaining a healthy indoor *** advancement in emerging digital twin technologies including building information modeling(BIM),Internet of Things(IoT),data analytics,and smart control have led to new opportunities for building design and *** the numerous studies on developing methods for creating digital twins and enabling new functionalities and services in smart building management,very few have focused on the health of indoor *** is a critical need for understanding and envisaging how digital twin paradigms can be geared towards healthy indoor ***,this study reviews the techniques for developing digital twins and discusses how the techniques can be customized to contribute to public ***,the current applications of BIM,IoT sensing,data analytics,and smart building control technologies for building digital twins are reviewed,and the knowledge gaps and limitations are discussed to guide future research for improving environmental and occupant ***,this paper elaborates a vision for future research on integrated digital twins for a healthy indoor environment with special considerations of the above four emerging techniques and *** review contributes to the body of knowledge by advocating for the consideration of health in digital twin modeling and smart building services and presenting the research roadmap for digital twin-enabled healthy indoor environment.

关键词： digital twin healthy indoor environment building information modeling occupant–building interaction COVID-19

二氧化硅纳米颗粒暴露对莱茵衣藻生长及细胞代谢的影响

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防化研究 2024年第4期3卷 67-76页

作者：陶美胡雨晴赖金龙罗学刚张宇西南科技大学环境与资源学院生物质材料教育部工程研究中心西南科技大学生命科学与工程学院

为评估二氧化硅纳米颗粒（Silica Nanoparticles, SiO2NPs）对淡水微藻的影响，本研究以莱茵衣藻为供试对象，分析了不同浓度SiO2NPs暴露对莱茵衣藻生长速率、活性氧（Reactive Oxygen Species, ROS）、叶绿素和微藻代谢网络的影响。研... 详细信息

为评估二氧化硅纳米颗粒（Silica Nanoparticles, SiO2NPs）对淡水微藻的影响，本研究以莱茵衣藻为供试对象，分析了不同浓度SiO2NPs暴露对莱茵衣藻生长速率、活性氧（Reactive Oxygen Species, ROS）、叶绿素和微藻代谢网络的影响。研究发现：当SiO2NPs为400～800 mg/L时，其可显著抑制莱茵衣藻的增殖；200～800 mg/L的SiO2NPs暴露后，莱茵衣藻叶绿素a和叶绿素b的浓度分别较对照组下降27.89%～42.16%和16.28%～26.3%，且藻细胞内产生的ROS较对照组上升9.25%～24.9%;100 mg/L和800 mg/L的SiO2NPs显著改变了莱茵衣藻的代谢网络，包括脂质和类脂质分子、有机杂环化合物、有机酸及其衍生物等。通过代谢物分类注释基础代谢网络后分析发现，SiO2NPs影响了莱茵衣藻甘油磷脂类和有机杂环化合物代谢，特别是吲哚、吡啶、咖啡因等，并导致莱茵衣藻碳水化合物代谢、核苷酸合成、脂类和氨基酸代谢等基础代谢过程异常。本研究可为探索SiO2NPs对微藻的生物效应提供一定的理论基础和数据支持。

关键词：二氧化硅纳米颗粒莱茵衣藻代谢组学生长曲线活性氧

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智慧国土构建的技术模式研究--以重庆为例

时空信息学报 2024年第2期31卷 196-204页

作者：刘晓瑜刘万增杨凯胡渝清翟曦重庆市规划和自然资源调查监测院重庆401120 国家基础地理信息中心北京100830

智慧国土是统筹自然资源与地理空间数字化发展、促进智慧化应用、赋能高质量发展的重要举措。当前,尽管关于智慧国土的相关研究成果较多,但针对智慧国土技术模式的研究尚不多见,既有为数不多的技术模式的研究也不能完全适用于当前数字... 详细信息

智慧国土是统筹自然资源与地理空间数字化发展、促进智慧化应用、赋能高质量发展的重要举措。当前,尽管关于智慧国土的相关研究成果较多,但针对智慧国土技术模式的研究尚不多见,既有为数不多的技术模式的研究也不能完全适用于当前数字中国建设架构,因此,本文开展智慧国土构建的技术模式探讨。首先,本文从当前智慧国土构建中存在的不足出发,提出从信息到知识,从知识到智慧为主线的总体构建思路,总结形成以全面动态感知、系统精准认知、全域智慧管控为特征的智慧国土构建总体技术框架;其次,在分析重庆智慧国土构建技术现状与存在问题的基础上,讨论重庆智慧国土构建的技术创新方向与重点任务;最后,针对当前智慧国土发展现状,为下一步智慧国土构建提出相应建议。研究成果旨在为智慧国土实践的技术创新方向与重点攻关任务提供参考。

关键词：智慧国土技术模式技术创新时空数据时空信息时空知识国土空间规划智慧管控

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无接触服务研究述评与未来展望

科技管理研究 2024年第8期44卷 92-99页

作者：胡雨晴陈远高周莎莎杨水清李一啸浙江财经大学管理学院浙江杭州310018

在智能化技术运用日渐广泛以及孤独经济的影响下,基于现代智能信息技术的无接触服务在社会各方面发挥重要作用,因此需要在回顾无接触服务相关研究的基础上提出未来技术发展方向。无接触服务是一种非面对面提供信息或商品的服务方式,其... 详细信息

在智能化技术运用日渐广泛以及孤独经济的影响下,基于现代智能信息技术的无接触服务在社会各方面发挥重要作用,因此需要在回顾无接触服务相关研究的基础上提出未来技术发展方向。无接触服务是一种非面对面提供信息或商品的服务方式,其与自助服务在技术层面和应用环境层面上有一定差异,是自助服务的高级阶段。采用文献回顾的方法对2016—2022年与无接触服务相关的206篇中英文文献进行系统梳理,通过可视化和词频分析发现,中国学者在新冠疫情前对无接触服务的关注相对比较少。相关研究中,消费者层面主要关注无接触服务的用户行为,但存在用户隐私泄露以及道德伦理上的问题;企业层面更关注无接触技术的采纳,但因无接触服务不稳定或学习成本高等原因,用户拒绝使用无接触服务可能对企业绩效产生一些负面影响;政府层面则更关注整个行业的转型与数字化,但需要出台和完善相关措施解决分配不公、隐私泄露、法律缺失等问题。未来相关研究应进一步完善无接触服务的理论基础;考虑无接触服务对消费者行为的影响,尤其是负面影响;聚焦于无接触服务对企业绩效变化、政府职能等方面的影响,同时要关注未使用过无接触服务技术或新形成的消费群体,以及如“人-机”协同等新型劳动形式的有关法律保障等问题。与此同时,未来的实证研究需要高度重视数据来源问题,以及考虑使用纵向研究方法和融入如多群体分析、概率抽样与非概率抽样对比等各种分析方法。为推动无接触服务的广泛运用,消费者应积极学习相关使用方式并给出改进意见;企业则要考虑不同顾客群体的需求、提供更加定制化的服务;政府要大力宣传无接触服务的必要性,并为中小企业提供低成本的人工智能算力、算法和数据资源。

关键词：无接触服务人工智能智能服务文献综述研究展望文献计量

Heavy metals potentially drive co-selection of antibiotic resistance genes by shifting soil bacterial communities in paddy soils along the middle and lower Yangtze River

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Pedosphere 2024年第3期34卷 606-619页

作者： Ya ZHANG Hao WANG Minghui hu Rui CAI yuqing MIAO Xiancan Zhu Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Metabolic Diseases Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological ResourcesCollege of Life SciencesAnhui Normal UniversityWuhu 241000(China) School of Geography and Tourism Anhui Normal UniversityWuhu 241003(China)

Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human *** microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;however,the interactions among HMs,soil microbial communities,and antibiotic resistance genes(ARGs)in agricultural soils remain *** quantitative real-time polymerase chain reaction and NovaSeq sequencing,we evaluated heavy metal contents,abundances of ARGs,soil bacterial community structure and functions,and their correlations in paddy soils at 43 sampling sites along the middle and lower reaches of the Yangtze River,central and eastern *** results showed the co-occurrence of HMs,ARGs,and HM resistance genes across all paddy ***,significant positive associations were detected between HMs and resistance ***,czcA,and int1 were positively correlated with bacterial community *** Mantel test showed that bacterial community composition and functions were significantly associated with HMs and resistance genes,such as Cd,Cr,Zn,copA,czcA,int1,and ***,HMs and ARGs were the major factors shaping soil bacterial communities;thus,HMs triggered proliferation of HM and antibiotic resistances by influencing the mobile genetic element(int1)and soil microbial *** study revealed that HMs potentially drive the co-selection of ARGs by shifting soil bacterial community structure and functions,thereby increasing the potential risks to human health as well as ecological environment in the paddy soils along the middle and lower reaches of the Yangtze River.

关键词： agricultural ecosystem ecological risk heavy metal resistance microbial community soil contamination soil pollution

De novo transcriptome assembly and metabolomic analysis of three tissue types in Cinnamomum cassia

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Chinese Herbal Medicines 2023年第2期15卷 310-316页

作者： Hongyang Gao huiju Zhang yuqing hu Danyun Xu Sikai Zheng Shuting Su Quan Yang School of Traditional Chinese Medicine Guangdong Pharmaceutical UniversityGuangzhou 510006China Key Laboratory of Production&Development of Cantonese Medicinal Materials State Administration of Traditional Chinese MedicineGuangzhou 510006China Guangdong Provincial Research Center on Good Agricultural Practice&Comprehensive Agricultural Development Engineering Technology of Cantonese Medicinal Materials Guangzhou 510006China Comprehensive Experimental Station of Guangzhou Chinese Material MedicaChina Agriculture Research System(CARS-21-16)Guangzhou 510006China

Objective:The barks,leaves,and branches of Cinnamomum cassia have been historically used as a traditional Chinese medicine,spice,and food preservative,in which phenylpropanoids are responsible *** phenylpropanoid biosynthesis pathways are not clear in *** elucidated the pathways by descriptive analyses of differentially expressed genes related to phenylpropanoid biosynthesis as well as to identify various phenylpropanoid ***:Chemical analysis,metabolome sequencing,and transcriptome sequencing were performed to investigate the molecular mechanisms underlying the difference of active components content in the barks,branches and leaves of ***:Metabolomic analysis revealed that small amounts of flavonoids,coumarine,and cinnamaldehyde accumulated in both leaves and *** analysis showed that genes associated with phenylpropanoid and flavonoid biosynthesis were downregulated in the leaves and branches relative to the *** observed differences in essential oil content among the three tissues may be attributable to the differential expression of genes involved in the phenylpropanoid and flavonoid metabolic ***:This study identified the key genes in the phenylpropanoid pathway controling the flavonoid,coumarine,and cinnamaldehyde contents in the barks,branches and leaves by comparing the transcriptome and *** findings may be valuable in assessing phenylpropanoid and flavonoid metabolites and identifying specific candidate genes that are related to the synthesis of phenylpropanoids and flavonoids in ***.

关键词： Cinnamomum cassia Presl metabolomic phenylpropanoid biosynthesis transcriptome