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Influences of WTO Entry on China's Car Industry

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中国汽车（英文版） 2001年第5期 8-11页

作者： By wang zude & Cui Zenghui, catarc

Many evidences show that China has hope of entering WTO in the second half of 2001, which will influence Chinese industries undoubtedly, especially the car industry due to its Iow technical level, high price and dependent development ability. However. Objectively speaking Chinese car industry will face challenges and opportunities when joining WTO.

关键词：二二三

Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

公路转弯段线形指标对混凝土护栏安全性能的影响

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华南理工大学学报（自然科学版） 2024年第1期52卷 90-99页

作者：杨永红唐祖德王醇朱冠儒华南理工大学土木与交通学院广东广州510640 广东省隧道工程安全与应急保障技术及装备企业重点实验室广东广州510545 长沙理工大学公路工程教育部重点实验室湖南长沙410114

公路转弯段的线形设计指标对护栏的安全性能有重要影响。文中基于路侧安全领域广泛使用的有限元软件LS-DYNA,通过模拟和实车试验对比验证模型的有效性,建立货车与混凝土护栏复杂碰撞试验模型,模拟计算得到车辆碰撞护栏的详细动画,作为... 详细信息

公路转弯段的线形设计指标对护栏的安全性能有重要影响。文中基于路侧安全领域广泛使用的有限元软件LS-DYNA,通过模拟和实车试验对比验证模型的有效性,建立货车与混凝土护栏复杂碰撞试验模型,模拟计算得到车辆碰撞护栏的详细动画,作为平曲线路段上护栏安全性能的直观感受,将行车道半径、路面超高、车辆速度作为变量,研究和量化主要线形指标对混凝土护栏安全性能的影响。结果表明:道路半径接近与设计速度对应的极限最小半径时,车辆的翻滚角增大,车辆易碰撞护栏发生侧翻;行车道路面超高6%为混凝土护栏安全性能的临界点,采用大于6%的超高会使车辆沿护栏迎撞面爬坡跃升的高度增加,车辆更容易发生侧翻,设计时应避免大超高(6%以上)和小半径极值的组合;在曲线路段,碰撞速度对护栏安全性能的影响明显,整体式货车车速达90 km/h后,发生侧翻的风险明显增加。文中研究成果可为道路曲线路段路侧的线形安全设计提供理论基础。

关键词：道路工程公路线形指标混凝土护栏碰撞试验安全性能

Pushing the boundaries: an interview with Dae-Hyun Kim on terahertz devices

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National Science Review 2024年第3期11卷 42-45页

作者： Defu wang the Center for Carbon-based Electronics School of Electronics Peking University

Ⅲ–Ⅴ compound semiconductors, such as InGaAs/InAlAs, exhibit exceptional carrier transport properties, establishing them as fundamental elements in terahertz(THz) applications crucial for the development of 6G netwo...

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Enrichment of anammox biomass during mainstream wastewater treatment driven by achievement of partial denitrification through the addition of bio-carriers

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Journal of Environmental Sciences 2024年第3期137卷 181-194页

作者： Yuqing Ma Bo wang Xiaodi Li Shuo wang Wen wang Yongzhen Peng National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China

Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especially in mainstream wastewater treatment.In this study,the feasibility of enrichment of anammox biomass was explored through the realization of partial denitrification and the addition of bio-carriers.By using ordinary activated sludge,a sequencing batch reactor(SBR)followed by an up-fow anaerobic sludge bed(UASB)was operated at 25±2℃ for 214 days.The long-term operation was divided into five phases,in which SBR and UASB were started-up in Phases I and II,respectively.By eliminating oxygen and adjusting the infow ratios in Phases III-V,advanced nitrogen removal was achieved with the effuent total nitrogen being 4.7 mg/L and the nitrogen removal efficiency being 90.5%in Phase V.Both in-situ and ex-situ activity tests demonstrated the occurrence of partial denitrification and anammox.Moreover,16S rRNA high-throughput sequencing analysis revealed that Candidatus Brocadia was enriched from below the detection limit to in biofilms(0.4%in SBR,2.2%in UASB)and the foc sludge(0.2%in SBR,1.3%in UASB),while Thauera was mainly detected in the foc sludge(8.1%in SBR,8.8%in UASB),which might play a key role in partial denitrification.Overall,this study provides a novel strategy to enrich anammox biomass driven by rapid achievement of partial denitrification through the addition of bio-carriers,which will improve large-scale application of anammox processes in mainstream wastewater treatment.

关键词： Enrichment Anammox biomass Bio-carriers Partial denitrification Mainstream wastewater

Performance and mechanism of La-Fe metal-organic framework as a highly efficient adsorbent for fluoride removal from mine water

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Journal of Environmental Sciences 2024年第5期139卷 245-257页

作者： Chaomin Jia Jianbing wang Huijiao wang Sichao Zhu Xiaohui Zhang Yuxiang wang School of Chemical&Environmental Engineering China University of Mining&Technology-BeijingBeijing 100083China Beijing Polytechnic Beijing 100176China Chinese Society for Urban Studies Beijing 100835China

Water fluoride pollution has caused non-negligible harm to the environment and humans,and thus it is crucial to find a suitable treatment technology.In this study,La-Fe@PTA adsorbent was synthesized for the defluoridation of mine water.The results showed that the optimum conditions for defluoridation by La-Fe@PTA were p H close to 7.0,the initial F-concentration of 10 mg/L,the dosage of 0.5 g/L and the adsorption time of 240 min.Compared with SO_4^(2-),Cl^(-),NO_(3)^(-),Ca^(2+)and Mg^(2+),CO_(3)^(2-)and HCO_(3)^(-)presented severer inhibition on fluoride uptake by La-Fe@PTA.The adsorption process fits well with the pseudo-second-order kinetic model and Freundlich model,and the maximum adsorption capacity of Langmuir model was 95 mg/g.Fixed-bed adsorption results indicated that fluoride in practical fluorinated mine water could be effectively removed from 3.6 mg/L to less than 1.5 mg/L within130 bed volume(BV)by using 1.5 g La-Fe@PTA.Furthermore,the adsorbent still had good adsorption capacity after regeneration,which confirms the great application potential of La-Fe@PTA as a fluoride ion adsorbent.The mechanism analysis showed that La-Fe@PTA adsorption of fluorine ions is a physicochemical reaction driven by electrostatic attraction and ion exchange.

关键词： Adsorption La-Fe@PTA Fluoride ion Mine water Mechanism

Analysis of Hot Topics Regarding Global Smart Elderly Care Research—1997-2021

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China CDC weekly 2024年第9期6卷 157-161页

作者： Hongman wang Hong Chen Yuqi wang School of Health Humanities Peking UniversityBeijingChina Center for Global Public Health Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?With the assistance of the internet,big data,cloud computing,and other technologies,the concept of smart elderly care has emerged.What is added by this report?This study presents information on the countries or regions that have conducted research on smart elderly care,as well as identifies global hotspots and development trends in this field.

关键词： Smart internet smart

Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： Ziye wang Xia Liu Pinyao wang Huanyu Lu Bo Meng Wei Zhang Lijie wang Yanjing wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning Dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and ranging.Lasers operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe threshold.However,high interband absorption significantly decreases their performance at this 1.55μm wavelength.Therefore,stronger optical feedback is needed to reduce their threshold and thus improve the output power.Toward this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often used.Nevertheless,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final yield.In this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical feedback.Using this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice structure.Detailed theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design principles.Our findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng wang Xiaoqi wang Shuiyuan Cheng Jiaxian Zhu Xinyu Zhang Long Cheng Kai wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in China.We estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research results.Then,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was analyzed.Moreover,priority control routes for VOC emission sources were proposed for different periods.Anthropogenic VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main contributors.Industrial protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and SOAFP.Priority in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in China.In addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route