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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

增强现实(AR)技术环境下真实与虚拟关系的实在性分析

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自然辩证法通讯 2021年第4期43卷 40-46页

作者：王安然北京师范大学哲学学院北京100875

增强现实(AR)技术具有虚实结合、实时交互、虚实配准的特性,可以消解经典实在论下真实与虚拟关系面对的挑战。沟通技术与现实的科技连续统不能直观贴切地表现实在世界中真实和虚拟的关系。基于三重实在理论,可以重新规范真实与虚拟的含... 详细信息

增强现实(AR)技术具有虚实结合、实时交互、虚实配准的特性,可以消解经典实在论下真实与虚拟关系面对的挑战。沟通技术与现实的科技连续统不能直观贴切地表现实在世界中真实和虚拟的关系。基于三重实在理论,可以重新规范真实与虚拟的含义。借助对真实世界和虚拟世界三种形态的实在成分分析,三个世界的关系由一维线图转变为二维面图。借此可以表述出运用AR技术复刻及修改场景的所有可能性。AR世界构建了真实世界与虚拟世界的联系,是二者之间的过渡。虽然需要AR作为过渡的桥梁,但这并不意味着真实世界与虚拟世界的断裂。

关键词：感知实在符号实在真实虚拟

强吸波催化剂协同微波能强化果糖脱水制5-羟甲基糠醛

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化工学报 2024年第4期75卷 1565-1577页

作者：徐安冉刘凯王娜赵振宇李洪高鑫天津大学化工学院精馏技术国家工程研究中心天津300072 物质绿色创造与制造海河实验室天津300192

利用硬模板法制备了中空多孔碳球(MHCS),系统研究了热处理温度、金属负载量、刻蚀前后对MHCS电磁参数的影响。从中选取高介电损耗值(ε″)的MHCS-800(ε″=213)作为催化剂载体,并以SCS-800(ε″=50)和SCS(ε″=0.08)作为对比样品,经磺... 详细信息

利用硬模板法制备了中空多孔碳球(MHCS),系统研究了热处理温度、金属负载量、刻蚀前后对MHCS电磁参数的影响。从中选取高介电损耗值(ε″)的MHCS-800(ε″=213)作为催化剂载体,并以SCS-800(ε″=50)和SCS(ε″=0.08)作为对比样品,经磺化后用于催化果糖水解制5-羟甲基糠醛,根据在微波加热和常规油浴条件下的反应动力学探究了ε″对微波催化效果的影响。结果表明,在80 W微波功率辐照下使用MHCS-800-SO_(3)H作为催化剂,5 min转化率即可达97.7%;反应速率常数(k)为0.76 min^(-1),是常规加热(k=0.0847 min^(-1))的8.97倍,该催化剂相较于SCS-800-SO_(3)H和SCS-SO_(3)H的微波催化效果(k比常规分别提升了164.9%、11.9%)更加显著。以上研究结果源于中空多孔结构和高的石墨化程度相耦合更有利于在催化剂颗粒表面形成“热点”,从而加速催化反应。

关键词：微波辐照果糖水解多相反应动力学介电损耗催化

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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

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3种叶形泰山白首乌DNA条形码分子鉴定

分子植物育种 2022年第10期20卷 3300-3305页

作者：李洁盛可心王玉清王飞王安冉徐凌川山东中医药大学药学院济南250355 山东御华景宸生态农业发展有限公司临沂273418

应用DNA条形码技术鉴定3种叶形泰山白首乌,探究泰山白首乌不同单株上叶片形状遗传变异规律,探讨其定为变种(亚种)的可能性。确定能用于该种植物鉴定的DNA条形码,为泰山白首乌优质品种的资源储存以及开发利用提供研究基础。采用改良CTAB... 详细信息

应用DNA条形码技术鉴定3种叶形泰山白首乌,探究泰山白首乌不同单株上叶片形状遗传变异规律,探讨其定为变种(亚种)的可能性。确定能用于该种植物鉴定的DNA条形码,为泰山白首乌优质品种的资源储存以及开发利用提供研究基础。采用改良CTAB法提取泰山白首乌叶片基因组DNA,利用ITS2和psbA-trnH引物对样品进行PCR扩增,电泳检测后进行双向测序。通过GenBank数据库,对3种叶形的植物样品进行比对,分析碱基变异位点和遗传变异程度。ITS2条形码扩增效率高且数据稳定可靠,3种叶形的样品内共有2个变异位点。3种叶形的psbA-trnH序列相同,未见碱基位点的变异。结论:从分子角度研究异株泰山白首乌的叶片形状遗传变异规律,ITS2仅有两个位点变异,psbA-trnH序列相同,3种叶形泰山白首乌不能确定为变种(亚种),但ITS2可作为标记泰山白首乌3种叶形变异的参考序列。

关键词：泰山白首乌叶片形状 DNA条形码遗传变异

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

Effects of operating conditions on iron(hydr)oxides evolution and ciprofloxacin degradation in potassium ferrate-ozone stepwise oxidation system

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Journal of Environmental Sciences 2024年第1期135卷 367-378页

作者： Xiaochen Li Yifan wang Ning wang Mei Li Maomao Bai Jingtao Xu Hongbo wang School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resources and Environment Innovation Institute Shandong Jianzhu UniversityJinan 250101China

In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K_(2)FeO_(4) reduction products(iron(hydr)oxides)and CIP degradation were investigated.It was found that in addition to its own oxidation capacity,K_(2)FeO_(4) can also influence the treatment effect of CIP by changing the catalyst content.The presence of iron(hydr)oxides effectively enhanced the mineralization rate of CIP by catalyzing ozonation.The pH value can influence the content and types of the components with catalytic ozonation effect in iron(hydr)oxides.The K_(2)FeO_(4) pre-oxidation stage can produce more iron(hydr)oxides with catalytic components for subsequent ozonation,but the evolution of iron(hydr)oxides components was influenced by O_(3) treatment.It can also avoid the waste of oxidation capacity owing to the oxidation of iron(hydr)oxides by O_(3) and free radicals.The intermediate degradation products were identified by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Besides,the degradation pathways were proposed.Among the degradation products of CIP,the product with broken quinolone ring structure only appeared in the stepwise oxidation system.

关键词： Potassium ferrate reduction products Catalytic ozonation Ciprofloxacin Potassium ferrate pre-oxidation time

Evolution of artificial ion channels

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National Science Review 2024年第1期11卷 72-73页

作者： Yugang wang School of Physics Peking University

Protein ion channels on a cell membrane generate action potentials for cellular signal transduction, and regulate biological activities during life. Since the discovery of the asymmetric ion transport phenomenon in quartz nanopipettes by Bard and colleagues [1], synthetic nanofluidic materials and devices have attracted a lot of research interests from the scientific community,

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Chemical characteristics of long-term acid rain and its impact on lake water chemistry:A case study in Southwest China

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Journal of Environmental Sciences 2024年第4期138卷 121-131页

作者： Liuyi Zhang Jiawang Shuxiao wang Chunbo wang Fumo Yang Tingzhen Li Chongqing Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir Chongqing Three Gorges UniversityWanzhou 404000China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China College of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China National Engineering Research Center on Flue Gas Desulfurization Chengdu 610065China

The chemical composition of acid rain and its impact on lake water chemistry in Chongqing,China,from 2000 to 2020 were studied in this study.The regional acid rain intensity is affected jointly by the acid gas emissions and the neutralization of alkaline substances.The pH of precipitation experienced three stages of fluctuating decline,continuous improvement,and a slight correction.Precipitation pH showed inflection points in 2010,mainly due to the total control actions of SO_(2)and NO_(x)implemented in 2011.The total ion concentrations in rural areas and urban areas were 489.08μeq/L and 618.57μeq/L,respectively.The top four ions were SO_(4)^(2-),Ca^(2+),NH_(4)^(+)and NO_(3)^(-),which accounted for more than 90%of the total ion concentration,indicating the anthropogenic effects.Before 2010,SO_(4)^(2-)fluctuated greatly while NO_(3)^(-)continued to rise;however,after 2010,both SO_(4)^(2-)and NO_(3)^(-)began to decline rapidly,with the rates of-12.03μeq/(L·year)and-4.11μeq/(L·year).Because the decline rate of SO_(4)^(2-)was 2.91 times that of NO_(3)^(-),the regional acid rain has changed from sulfuric acid rain to mixed sulfuric and nitric acid rain.The lake water is weakly acidic,with an average pH of 5.86,and the acidification frequency is 30.00%.Acidification of lake water is jointly affected by acid deposition and acid neutralization capacity of lake water.Acid deposition has a profound impact on water acidification,and nitrogen(N)deposition,especially reduced N deposition,should be the focus of future research.

关键词： Acid rain Chemical composition Neutralization Nitrogen deposition Water acidification