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Occurrence and risks of pharmaceuticals,personal care products,and endocrine-disrupting compounds in Chinese surface waters

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Journal of Environmental Sciences 2024年第12期146卷 251-263页

作者： Yuhang Chen Mengyuan Li Weichun gao Yinyan Guan Zhineng Hao Jingfu Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environmental and Chemical Engineering Shenyang University of TechnologyShenyang 110870China College of Environmental Science and Engineering China West Normal UniversityNanchong 637009China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

The continuous and rapid increase of chemical pollution in surface waters has become a pressing and widely recognized global *** emerging contaminants(ECs)in surface waters,pharmaceutical and personal care products(PPCPs),and endocrine-disrupting compounds(EDCs)have attracted considerable attention due to their wide occurrence and potential threat to human ***,a comprehensive understanding of the occurrence and risks of ECs in Chinese surface waters is urgently *** study summarizes and assesses the environmental occurrence concentrations and ecological risks of 42 pharmaceuticals,15 personal care products(PCPs),and 20 EDCs frequently detected in Chinese surface *** ECs were primarily detected in China’s densely populated and highly industrialized *** detected PPCPs and EDCs had concentrations between ng/L toμg/L,whereas norfloxacin,caffeine,and erythromycin had relatively high contamination levels,even exceeding 2000 ng/*** evaluation based on the risk quotient method revealed that 34 PPCPs and EDCs in Chinese surface waters did not pose a significant risk,whereas 4-nonylphenol,4-tert-octylphenol,17α-ethinyl estradiol,17β-estradiol,and triclocarban *** review provides a comprehensive summary of the occurrence and associated hazards of typical PPCPs and EDCs in Chinese surface waters over the past decade,and will aid in the regulation and control of these ECs in Chinese surface waters。

关键词： Pharmaceuticals and personal care products(PPCPs) Endocrine-disrupting compounds (EDCs) Surface waters Occurrence Risk assessment Prioritization

Understanding the alkyl effect of geminal dinitropropyl ester energetic plasticizers on hydroxyl terminated polybutadiene(HTPB):Simultaneous tuning on low temperature behavior and processability

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Chinese Journal of Chemical Engineering 2023年第2期54卷 364-371页

作者： Baodong Zhao Yinglei Wang Fulei gao Yajing Liu Weixiao Liu Feng Ding Xi'an Modern Chemistry Research Institute Xi'an 710065China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an 710065China

Geminal dinitropropyl ester plasticizers(DNPEPs) possess excellent energetic performances which provide good potentials as insensitive plasticizer. In this study, we design and synthesize DNPEPs with different alkane chain parts, and systematically investigate their structure-property *** show that DNPEPs have impact sensitivities all higher than 25.2 J, thermal decomposition temperatures all higher than 254 ℃, and glass transition temperatures(T_(g)) lower than-90 ℃.Furthermore, the effects of DNPEPs as plasticizer are studied on hydroxyl terminated polybutadiene(HTPB) in detail, including the viscosity, glass transition temperatures and others. It is noteworthy that 2,2-dinitropropyl nonanoate(DNPNc) among these DNPEPs exhibits the most expected simultaneous tuning effects on both viscosity and T_(g) of HTPB systems, providing favorable potentials to replace the conventional plastizers as dioctyl sebacate(DOS) in the HTPB based propellants and explosives.

关键词： Molecular simulation Experimental validation Preparation Energetic plasticizer Glass transition temperature Viscosity

Research on optimization and design methods for air distribution system based on target values

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Building Simulation 2021年第3期14卷 721-735页

作者： Ran gao Hengchun Zhang Angui Li Shihao Wen Wuyi Du Baoshun Deng School of Building Services Science and Engineering Xi'an University of Architecture and TechnologyXi'an 710055China School of Thermal Engineering Shandong Jianzhu UniversityJinan 250101ShandongChina China Railway First Survey&Design Institute Group Xi'an 710043China

To achieve sufficient air conditioning of large buildings,reasonable air distribution in indoor spaces is an effective method for creating stratified air ***,optimizing the air distribution in large buildings is extremely *** this paper,we expound on a new method for air distribution design and optimization based on target value evaluation and summarize the relevant design processes based on an orthogonal test and by decoupling the effects of the size of the tuyere,airflow temperature,air-supply angle and velocity on air ***,we present a design *** optimize the distribution of a lateral air supply in winter,the deflection angle,velocity and temperature of the air supply can be determined in *** the large and tall building types addressed in this paper,the optimal air-supply angle is 2°,the optimal air-supply velocity is 8 m/s,and the optimal air-supply temperature is 19℃.

关键词： air distribution target value indicator optimization

Tribological behavior of black phosphorus nanosheets as water-based lubrication additives

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Friction 2022年第3期10卷 374-387页

作者： Qingjuan WANG Tingli HOU Wei WANG Guoliang ZHANG Yuan gao Kuaishe WANG School of Metallurgy Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

Black phosphorus(BP)with a layered structure has been used gradually as a lubrication additive in the tribological *** this study,BP powders are produced via an easy method of high-energy ball milling using red phosphorus as a raw ***,BP nanosheets are prepared via liquid exfoliation in N-methyl pyrolidone *** tribological behavior of BP nanosheets as water-based lubrication additives(BP-WL)is evaluated under Ti6Al4V(TC4)/GCr15 *** results suggest that the 70 mg/L BP-WL sample exhibits excellent lubrication performance,whose coefficient of friction(COF)and ball wear rate reduced by 32.4%and 61.1%,respectively,compared with those of pure ***,as the load increased,the tribological properties of BP-WL reduced gradually because of the agglomeration of BP *** on tribological experiments and worn surface analysis,boundary lubrication mechanisms are *** friction reduced,which is primarily attributed to the low interlaminar shear and adsorption of BP *** addition,a tribochemical reaction film comprising TiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)effectively protects the surface of titanium alloy/steel from *** new water-based lubrication additive can be used to process titanium alloys.

关键词： black phosphorus(BP) tribological behavior lubrication additives titanium alloy/steel friction

Thermal annealing promoted room temperature phosphorescence: motion models and internal mechanism

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National Science Review 2023年第11期10卷 171-182页

作者： Yan gao Jie Lu Qiuyan Liao Shuhui Li Qianqian Li Zhen Li Tai Kang Center for Life and Medical Sciences Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Wuhan University Department of Chemistry

Thermal annealing has been proven to be an efficient method to optimize the device performance of organic and polymeric opto-electronic materials. However, no detailed information of aggregate structures was obtained for a deeper understanding of what happens during thermal annealing. Herein, through modulation of molecular configurations by tunable linkage positions, and the amplified amplitudes of molecular motions by incorporation of additional methylene units, accurate changes of aggregated structures upon thermal annealing have been achieved, accompanying with the ‘turn-on’ room temperature phosphorescence(RTP) response by about 4800-and 177-fold increase of lifetimes. The stretching and swing motion models have been proposed, which afforded an efficient way to investigate the science of dynamic aggregation in depth.

关键词： room temperature phosphorescence thermal annealing structural reconfiguration molecular motion intermolecular interaction

Control Research for a Small Fixed-Wing UAV DuringGround Taxiing

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Journal of Harbin Institute of Technology(New Series) 2017年第2期24卷 51-57页

作者： Jiuzhou gao Hongguang Jia Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100039China

Ground taxiing is the key process of take-off and landing for a tricycle-undercarriage unmanned aerial vehicle( UAV). Nonlinear model of a sample UAV is established based on stiffness and damping model of landing gears and tires taken into account. Then lateral nonlinear model is linearized and state space equations are deduced by using nose wheel and ruder as inputs and lateral states as outputs. Adaptive internal model control( AIMC) is proposed and applied to lateral control based on decoupled and linearized dynamic model during ground taxiing process. Different control strategies are analyzed and compared by simulations,and then a combined control strategy of nose wheel steering with holding and rudder control is given. Hardware in loop simulations( HILS) proves the validity of the controller designed.

关键词： ground taxiing landing gears and tires model AIMC control strategy HILS

Heat Insulation and Dissipation Processes in Nordic Seas in the Summer

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Journal of Ocean University of China 2021年第6期20卷 1297-1306页

作者： gao Lin ZHAO Jinping LI Shimin FAN Xiutao LIU Shixuan College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China National Marine Environmental Forecasting Center Beijing 100000China Institute of Oceanographic Instrumentation Shandong Academy of SciencesQingdao 266100China

The Nordic Seas have a significant impact on the climate *** 23-day air-sea heat fluxes were analyzed from an in situ air-sea coupled buoy deployed in the Lofoten Basin from 5 August 2012 to 27 August *** buoy captured two stages of strong south and north *** observations indicate that warm and wet air transported by the south wind can lead to decreased sensible and latent heat fluxes and net longwave *** total oceanic heat loss was 50-60Wm−***,this stage was called the heat insulation *** contrast,the heat dissipation process occurred with the north wind condition dur-ing advection of the cold and dry *** this process,sensible and latent heat fluxes and net longwave radiation notably *** total oceanic heat loss during the heat dissipation process reached 240Wm−2,which was four-fold greater than that in the heat insulation *** that the heat insulation process is dominant in summertime,the ocean lost minimal heat but absorbed strong solar ***,a large quantity of energy was stored in the *** was transported to the Arctic Ocean and accelerated Arctic *** heat dissipation process is dominant in autumn and winter when the ocean releases consid-erably more *** two processes revealed in this paper can be applied to warm-water areas in high latitudes.

关键词： Nordic Seas radiation flux heat flux air-sea interactions

Livelihood Vulnerability and Adaptation for Households Engaged in Forestry in Ecological Restoration Areas of the Chinese Loess Plateau

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Chinese Geographical Science 2024年第5期34卷 849-868页

作者： YANG Qingqing CHEN Yang LI Xiaomin YANG Jie gao Yanhui Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Geographical Science and Tourism Shaanxi Normal UniversityXi’an 710119China School of Tourism and Research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128China

Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic ***,synergistic development may not be realized at the local *** areas undergoing ecological restoration,livelihood vulner-ability may be more pronounced due to the inflexibility,policy protection,and susceptibility to climate and market changes in forestry *** this issue has attracted academic interest,empirical studies are relatively *** study,centered on Jiaxian County,Shaanxi Province of China explored the households’livelihood vulnerability and coping strategies and group heterogeneity con-cerned with livelihood structures or forestry resources through field investigation,comprehensive index assessment,and nonparametric *** showed that:1)the percentage of households with high livelihood vulnerability indicator(LVI)(>0.491)reached 46.34%.2)Eight groups in livelihood structures formed by forestry,traditional agriculture,and non-farm activities were significantly different in LVI,land resources(LR),social networks(SN),livelihood strategies(LS),housing characteristics(HC),and socio-demo-graphic profile(SDP).3)The livelihood vulnerability of the groups with highly engaged/reliance on jujube(Ziziphus jujuba)forest demonstrated more prominent livelihood vulnerability due to the increased precipitation and cold market,where the low-engaged with reliance type were significantly more vulnerable in LVI,SDP,LR,and HC.4)The threshold of behavioral triggers widely varied,and farmers dependent on forestry livelihoods showed negative coping ***,the cutting behavior was strongly associated with lagged years and government subsidies,guidance,and high returns of ***,the findings can provide guidance on the dir-ection of livelihood vulnerability mitigation and adaptive government management in ecologically restored *** issue of farmers’livelihood sustainability in the context of ecologi

关键词： livelihood vulnerability forestry coping behaviors climate change market change Jiaxian County

Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment

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International Journal of Mining Science and Technology 2024年第9期34卷 1259-1272页

作者： Haichun Hao Mingzhong gao Yan Wu Zheng gao Yongcheng Li Xuemin Zhou Peng Chu Xuan Wang Jiahua Li Lang Zhou Jie Song Tianxiang Ao Yikun Yang State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy Shenzhen UniversityShenzhen 518060China

The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and *** exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and *** and sampling are key to accurate exploration of the desirable characteristics of deep lunar *** this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was *** key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were *** results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated *** rotary-percussive drilling method effectively shortens the sampling *** increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady *** temperature rise energy accu

关键词： Lunar-based Large temperature difference Vacuum Drilling and coring System design