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Modeled exposure to phthalates via inhalation and dermal pathway in children's sleeping environment: A preliminary study and its implications

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Building Simulation 2021年第6期14卷 1785-1794页

作者： Zhongming Bu Cong Dong Daniel Mmereki Yanghui Ye zhu cheng Department of Energy and Environmental System Engineering Zhejiang University of Science and TechnologyHangzhou 310023China Faculty of Health Sciences School of Public HealthUniversity of the WitwatersrandParktown Education Campus2193 JohannesburgSouth Africa College of Architecture and Environment Sichuan UniversityChengdu 610065China

In this study,exposure to phthalates during children’s sleeping time was evaluated based on a mechanistic *** phase-specific concentrations in this model were estimated taking into account kinetic partitioning,particle dynamics and time-varying *** pathways considered were inhalation exposure to airborne phases,dermal absorption from "air-to-skin" transport and direct *** taking di(n-butyl)phthalate(DnBP)and bis(2-ethylhexyl)phthalate(DEHP)as two representative pollutants,inhalation exposure accounted for>90%when children wore clean pajamas before going to *** uptake significantly increased when children's pajamas had absorbed DnBP before putting them on,whereas dermal uptake of DEHP was relatively lower and insensitive to the condition of *** air exchange rate at night and keeping clothes cleaner were effective for reducing children's exposures during sleeping *** studies are necessary taking into account source-proximity effect,particle emissions and refined dermal exposure routes.

关键词： indoor air phthalates exposure children sleeping environment

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某型地铁转向架异常振动试验研究

铁道机车车辆 2024年第2期44卷 161-168页

作者：朱程徐步震贾小平胡定祥金鑫邬平波中车南京浦镇车辆有限公司技术中心南京210031 西南交通大学轨道交通运载系统全国重点实验室成都610031

针对某型转向架在服役过程中出现异常振动,基于Miner累积损伤理论和等损伤原则,利用轮轨振动传递的时频特性开展试验研究。试验结果表明,该转向架构架的等效应力幅值中100 Hz以内的低频区段能量占比最大,其中部分位置在70 Hz附近的能量... 详细信息

针对某型转向架在服役过程中出现异常振动,基于Miner累积损伤理论和等损伤原则,利用轮轨振动传递的时频特性开展试验研究。试验结果表明,该转向架构架的等效应力幅值中100 Hz以内的低频区段能量占比最大,其中部分位置在70 Hz附近的能量占比达18.78%~33.85%;结合轴承故障频率的理论计算、试验主频对比及拆解判定,振动主频70 Hz由轴承外环滚道上的缺陷故障产生;考虑到轴箱垂向振动存在与构架弹性模态相近的63 Hz主频,一定程度上加剧了转向架的振幅,而线路扣件的振动主频集中在350、430 Hz,对轮对轴箱系统的影响较大,对构架影响较小。该研究方法和结论对解决转向架局部振动等类似问题具有借鉴作用,为车辆的结构设计和运维管理提供一定的参考价值。

关键词：异常振动转向架动应力轴承故障时频分析

胶东招远-平度断裂地球物理异常特征及其控矿条件研究

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地质与勘探 2024年第4期60卷 776-784页

作者：许志河丁正江朱成庞森瑞范潍箐深部金矿探测大数据应用开发山东省工程研究中心山东威海264209 防灾科技学院地球科学学院河北廊坊065201 地热资源开发技术与装备教育部工程研究中心吉林长春130000 五矿勘查开发有限公司北京100010

招远-平度断裂是胶东金矿集区三条超大型控矿断裂(三山岛、焦家及招远-平度断裂)之一。受地表第四系覆盖影响,金矿体空间赋存位置与主断裂及其次级断裂地表出露位置的耦合关系尚存问题。通过开展精细化处理区域重力和航空磁测数据,如空... 详细信息

招远-平度断裂是胶东金矿集区三条超大型控矿断裂(三山岛、焦家及招远-平度断裂)之一。受地表第四系覆盖影响,金矿体空间赋存位置与主断裂及其次级断裂地表出露位置的耦合关系尚存问题。通过开展精细化处理区域重力和航空磁测数据,如空间域不同高度延拓(100 m、200 m和500 m)及垂向一阶导数等方法,发现招远-平度断裂地表出露位置与深部地球物理梯度带存在位移差,且位移差向断裂倾向方向南东侧移动趋势愈发明显,进一步证明招远-平度断裂深部倾向南东,倾角由浅至深逐渐变缓,局部变化剧烈的地质推论。同时,开展地表高精度1/10000比例尺的重力结果显示,重力异常曲线自西向东整体呈快速上升趋势,局部存在凹陷区,表明花岗质碎裂岩及绢英岩化花岗质碎裂岩密度(2.63 g/cm^(3))介于玲珑二长花岗岩(2.57 g/cm^(3))和古元古界(2.82 g/cm^(3))之间,含矿层位与围岩存在较大密度差,金矿体主要赋存于花岗质碎裂岩及绢英岩化花岗质碎裂岩层位的倾角由陡变缓或由缓变陡的转折部位,可分别发现石英脉型金矿和蚀变岩型金矿。

关键词：地球物理 2.5维反演布格重力异常剩余重力异常控矿构造识别招远-平度断裂胶东金矿集区

Archaeological discovery and research on the remains of the paleoflood of the Yuxi site

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Chinese Science Bulletin 2008年第S1期53卷 18-27页

作者： BAI JiuJiang ZOU HouXi zhu cheng Institute of Cultural Relics and Archaeology of Chongqing Chongqing 400013China Department of Geography and Sea Science of Nanjing University Nanjing 210093China

The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental *** on the traditional archaeological methods and the archaeological finds from the Yuxi site,Fengdu County of Chongqing,the paper analyzes the difference between the cultural layers and the possible paleoflood layers from various angles,such as contents,shapes of gravels,pottery,etc.,identifies the possible paleoflood deposit layers,*** paleoflood remains of the Yangtze River,and discusses the periodicity of the floods.

关键词： paleoflood environmental archaeology culture layer possible palieoflood layer Yuxi site

Community participation mode of ecotourism in Tibetan area of Shangri-La County, Yunnan Province

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Ecological Economy 2006年第3期2卷 306-318页

作者： cheng zhu Business and Tourism Management School Yunnan University Kunming 650091 P. R. China

Community participation is one of the focuses of the research on ecotourism. The research on community participative model is of great theoretical and practical significance. Based on the former experts’ studies, this paper analyzes ecotourism demonstration areas in Diqing Shangri-La of Yunnan as a case study. It mainly expounds the relationship between ecotourism and community participation and puts forward such a community participative model of ecotourism in Shangri-La.

关键词： Community participation Model Ecotourism Shangri-La Tibetan area

Greedysearch based service location in P2P networks

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Journal of Systems Engineering and Electronics 2005年第4期16卷 886-893页

作者： zhu cheng Liu Zhong Zhang Weiming Yang Dongsheng School of Information Systems and Management National Univ. of Defense Technology Changsha 410073 P. R. China

A model is built to analyze the performance of service location based on greedy search in P2P networks. Hops and relative QoS index of the node found in a service location process are used to evaluate the performance as well as the probability of locating the top 5% nodes with highest QoS level. Both model and simulation results show that, the performance of greedy search based service location improves significantly with the increase of the average degree of the network. It is found that, if changes of both overlay topology and QoS level of nodes can be ignored during a location process, greedy-search based service location has high probability of finding the nodes with relatively high QoS in small number of hops in a big overlay network. Model extension under arbitrary network degree distribution is also studied.

关键词： greedy-search service location P2P network.

Engineering a zinc binding site into the de novo designed protein DS119 with a βαβ structure

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Protein & Cell 2011年第12期2卷 1006-1013页

作者： cheng zhu Changsheng Zhang Huanhuan Liang Luhua Lai Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Center for Theoretical Biology Peking UniversityBeijing 100871China Present address:National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Functional proteins designed de novo have potential application in chemical engineering,agriculture and *** binding sites are commonly used to incorporate *** on a de novo designed protein DS119 with aβαβstructure,we have computationally engineered zinc binding sites into it using a home-made searching *** out of the eight designed sequences tested were shown to bind Zn2+with micromolar affinity,and one of them bound Zn2+with 1:1 *** is the first time that metalloproteins with anα,βmixed structure have been designed from scratch.

关键词： βαβ de novo design folding zincbinding

Mg-8Zn-4Al-0.5Cu-0.5Mn-xLi高模量铸造镁合金的组织和性能

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材料研究学报 2024年第3期38卷 187-196页

作者：刘晨野罗天骄李应举冯小辉黄秋燕郑策朱成杨院生中国科学院金属研究所沈阳110016 中国科学技术大学材料科学与工程学院沈阳110016

设计和制备Mg-8Zn-4Al-0.5Cu-0.5Mn-x Li(x=0,3,5,7)(%,质量分数)系列高比模量的镁合金,研究了它的组织和性能。Li含量为3.14%和5.37%的两种镁合金,其基体为单相α-Mg,在晶界析出骨骼状Mg_(32)(Al,Zn)49相,在晶粒内有颗粒状Mg_(5)Al_(2)Zn_(2)相和Al_(2)Mn相;Li含量为7.57%的合金,其基体主要为双相组织α-Mg+β-Li。添加Li元素后在晶界附近生成的共晶组织由α-Mg相和层片状AlLi相组成,并随着Li含量的提高层片状AlLi相的含量随之提高。随着Li含量的提高,合金的屈服强度呈逐渐提高的趋势,而抗拉强度基本上不变,合金的弹性模量呈现先提高后降低的趋势。铸态合金ZA84-5Li的弹性模量可达51.89 GPa,比纯Mg的弹性模量高7 GPa,但是其力学性能基本不变,屈服强度为141 MPa,抗拉强度为189 MPa,密度为1.71 g/cm^(3)。

关键词：金属材料镁合金第二相强化显微组织弹性模量

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2004年第z1期14卷 140-143页

作者： GUO Zhong-cheng zhu Xiao-yun XU Rui-dong Center of Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China Center of Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

Effects of pulse current on properties of electrodeposited RE-Ni-W-P-SiC composite coating were studied. The results show that hardness of the pulse current electrodeposited composite coatings is higher than that of the direct current electrodeposited composite coatings while other parameters are the same. Otherwise, the deposited velocity is higher, and wear resistance and corrosion resistance of the pulse current electrodeposited composite coatings are also improved when the average current density is 10 A/dm2 , pulse frequency is 800 Hz and duty ratio is 1: 5. The hardness of the coating as-deposited is HV500 - 700, and it reaches HV1300 after heat treatment at 400 ℃ for 1 h.

关键词： RE-Ni-W-P-SiC composite coating pulse current electrodeposition properties