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Comprehensive understanding on sources of high levels of fine particulate nitro-aromatic compounds at a coastal rural area in northern China

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Journal of Environmental Sciences 2024年第1期135卷 483-494页

作者： Yueru Jiang xinfeng wang Min Li Yiheng Liang Zhiyi Liu Jing Chen Tianyi Guan Jiangshan Mu Yujiao Zhu He Meng Yang Zhou Lan Yao Likun Xue Wenxing wang Environment Research Institute Shandong UniversityQingdao 266237China Department of Environmental Systems Science Swiss Federal Institute of Technology ZurichZurich 8092Switzerland Department of Water Resources and Drinking Water Swiss Federal Institute of Aquatic Science and TechnologyDuebendorf 8600Switzerland Qingdao Eco-Environment Monitoring Center of Shandong Province Qingdao 266003China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China

Nitro-aromatic compounds(NACs)are among the major components of brown carbon(BrC)in the atmosphere,causing negative impacts on regional climate,air quality,and ecological health.Due to the extensive origins,it is still a challenge to figure out the contributions and originating regions for different sources of atmospheric NACs.Here,field observations on fine particulate NACs were conducted at a coastal rural area in Qingdao,China in the winter of 2018 and 2019.The mean total concentrations of fine particulate nitro-aromatic compounds were 125.0±89.5 and 27.7±21.1 ng/m^(3)in the winter of 2018 and 2019,respectively.Among the measured eleven NACs,nitrophenols and nitrocatechols were the most abundant species.Variation characteristics and correlation analysis showed that humidity and anthropogenic primary emissions had significant influences on the NAC abundances.In this study,two tracing methods of the improved spatial concentration weighted trajectory(SCWT)model and the receptor model of positive matrix factorization(PMF)were combined to comprehensively understand the origins of NACs in fine particles at coastal Qingdao.Four major sources were identified,including coal combustion,biomass burning,vehicle exhaust,and secondary formation.Surprisingly,coal combustion was responsible for about half of the observed nitro-aromatic compounds,followed by biomass burning(~30%).The results by SCWT demonstrated that the coal combustion dominated NACs mainly originated from the Shandong peninsula and the areas to the north and southwest,while those dominated by biomass burning primarily came from local Qingdao and the areas to the west.

关键词： Nitro-aromatic compounds Fine particles Source apportionment Originating region Combustion activities

Crystalline cyclic(alkyl)(amino)stannylene via transient stannyne

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Science China Chemistry 2024年

作者： xinfeng wang Chaopeng Hu Zhihao Lu Liu Leo Liu Department of Chemistry and Research Center for Chemical Biology and Omics Analysis College of Science Southern University of Science and Technology

We demonstrate that a bulky cyclic amino ligand, specifically 1,1,3,3-tetraphenylisoindolinyl, can facilitate the formation of a transient stannyne, endowed with adjacent ambiphilic carbon and tin centers. This stannyne, manifesting carbene-like behavior,engages in an unprecedented sequence of reactions, including Buchner ring expansion, [1,3]sigmatropic, and [1,5]-sigmatropic shifts, culminating in the synthesis of a stable cyclic(alkyl)(amino)stannylene. This compound represents the first tin analogue of the well-known cyclic(alkyl)(amino)carbenes. Both the bonding configuration and the formation process of this stannylene are thoroughly analyzed through quantum chemical computations. Our findings pave the way for further synthesis of unusual main group species using bulky isoindolinyl substituents, emphasizing their potential as a versatile tool in synthetic chemistry.

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中国特色现代教育考试招生制度的实践逻辑与未来走向

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教育研究 2024年第6期45卷 17-27页

作者：王新凤钟秉林北京师范大学教育学部北京100875

新一轮考试招生制度改革实施十年来,形成了分类考试、综合评价、多元录取的考试招生模式,中国特色现代教育考试招生制度基本建立。考试招生制度改革过程是中央和地方政府治理格局重构、政府和高等学校招生权力博弈、个体理性与群体理性... 详细信息

新一轮考试招生制度改革实施十年来,形成了分类考试、综合评价、多元录取的考试招生模式,中国特色现代教育考试招生制度基本建立。考试招生制度改革过程是中央和地方政府治理格局重构、政府和高等学校招生权力博弈、个体理性与群体理性冲突、考试改革与课程改革同构的过程。在国家集权、统一高考、“应试教育”的制度惯性下,各种权力结构此消彼长,既呈现出一定的路径依赖,也在渐进式的变革中寻求新的动态平衡。在教育强国建设目标下,完善中国特色现代教育考试招生制度,应进一步优化教育治理结构,提升地方政府治理能力;扩大高等学校招生自主权,提高人才选拔效率;审慎研判新制度,重新思考个体理性选择;加强统筹规划,提升改革的协同性系统性。

关键词：考试招生制度分类考试综合评价多元录取实践逻辑

浅析市政给排水工程常见施工质量问题及控制措施

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智能城市应用 2024年第4期7卷 7-9页

作者：王昕峰衢州市市政公用管理服务中心浙江衢州324000

市政给排水工程是城市基础设施建设的重要组成部分,其施工质量直接关系到城市运行安全和居民生活质量。文章通过对市政给排水工程常见施工质量问题的分析,提出了相应的控制措施,以期为我国市政给排水工程质量控制提供参考。

关键词：市政给排水工程施工质量问题分析控制措施

Application of tobacco stems briquetting in tobacco flue-curing in rural area of China

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International Journal of Agricultural and Biological Engineering 2015年第6期8卷 84-88页

作者： wang xinfeng Xu Guizhuan Zhang Bailiang Jiao Youzhou Lu Haifeng Li Baoming Department of Agricultural Structure and Bio-environmental Engineering College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China Department of Bio-energy and Bio-environmental Engineering College of Mechanical&Electrical EngineeringHenan Agricultural UniversityZhengzhou 450002China

To reduce the conventional energy consumption in rural area of China,tobacco stems briquetting(TSB)was used as fuel during the process of tobacco flue-curing,compared with honeycomb briquette(HB).Three fire furnaces with different heat exchangers using TSB were compared using the tobacco flue-curing.The results showed that the smog temperature of TSB was higher than that of HB,the efficiency of bio-fuel system with TSB was from 43.5%to 54%,while the efficiency of traditional fuel system was 51.5%.And the cost of tobacco flue-curing per hectare with TSB and HB was$750.0 and$1282.5,respectively.It is proved that TSB is an alternative choice using for the industry of tobacco flue-curing,and the improvement in the structure of fire furnace could optimize the process of tobacco flue-curing.

关键词： biomass briquetting tobacco flue-curing bio-fuel fire furnace

Design of interference-imaging spectrum data transmission Card Based on PCI Bus

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微计算机信息 2005年第8Z期21卷 122-123页

作者： Ma, Dongmei Gao,Wei wang,xinfeng Xi＇an Institute of Optics and Precision Mechanismof CAS Shanxi Xi＇an 710068 Graduate School of China Association of Science Beijing 10048

Take the interference- imaging spectrometer for exam-ple, the paper analyses the characters of the spectrum- formingsignals and their timing sequence. Then inspects the key tech-nology in the interference - imaging spectrum data transmissionsystem, and indicates a design for the system- - which is basedon computer PCI bus with CPLD technique imbedded. The sys-tem’ s circuitry and function are also presented.

关键词：光谱干涉现象数据传输时间序列

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粉末冶金技术在溅射靶材制备中的研究现状

热加工工艺 2024年第7期53卷 7-10,36页

作者：姚甜王新锋刘李旭向长淑西安赛隆金属材料有限责任公司陕西西安710000 金属多孔材料国家重点实验室陕西西安710000

磁控溅射靶材由于沉积速率快、镀膜均匀等优点,已成为各类薄膜材料的首选制备方法。同时薄膜材料的广泛应用使得靶材的需求量逐年增多。近年来,粉末冶金技术在溅射靶材制备中得到了广泛应用。本文对靶材制备中使用的粉末冶金技术进行总... 详细信息

磁控溅射靶材由于沉积速率快、镀膜均匀等优点,已成为各类薄膜材料的首选制备方法。同时薄膜材料的广泛应用使得靶材的需求量逐年增多。近年来,粉末冶金技术在溅射靶材制备中得到了广泛应用。本文对靶材制备中使用的粉末冶金技术进行总结和工艺分析,并阐述热压烧结、热等静压烧结、放电等离子烧结的研究现状,最后探讨靶材制备研究中存在的技术问题和发展趋势。

关键词：粉末冶金靶材热压烧结热等静压烧结放电等离子烧结

Size Distributions of Aerosol Sulfates and Nitrates in Beijing during the 2008 Olympic Games： Impacts of Pollution Control Measures and Regional Transport

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Advances in Atmospheric Sciences 2013年第2期30卷 341-353页

作者： wang xinfeng wang Tao Ravi Kant PATHAK Mattias HALLQUIST GAO Xiaomeit NIE Wei XUE Likun GAO Jian GAO Rui ZHANG Qingzhu wang Wenxing wang Shulan CHAI Fahe CHEN Yizhen Environment Research Institute Shandong University Jinan 250100 Department of Civil and Environmental Engineering Hong Kong Polytechnic University Hong Kong Chinese Research Academy of Environmental Science Beijing 100012 Department of Chemistry University of Gothenburg Gothenburg Sweden

For the 2008 Olympic Games, drastic control measures were implemented on industrial and urban emissions of sulfur dioxide （SO2）, nitrogen oxides （NOx） and other pollutants to address the issues of poor air quality in Beijing. To investigate the effects of SO2 and NOx reductions on the particulate sulfate and nitrate concentrations as well as their size distributions, size-segregated aerosol samples were collected using micro-orifice uniform deposit impactors （MOUDIs） at urban and downwind rural sites in Beijing before and after full-scale controls. During the sampling period, the mass concentrations of fine particles （PMI.s） at the urban and rural sites were 94.0 and 85.9 p.g m-3, respectively. More than 90% of the sulfates and 60% of nitrates formed as fine particles. Benefiting from the advantageous meteorological conditions and the source controls, sulfates were observed in rather low concentrations and primarily in condensation mode during the Olympics. The effects of the control measures were separately analyzed for the northerly and the southerly air-mass-dominated days to account for any bias. After the control measures were implemented, PM, sulfates, and nitrates were significantly reduced when the northerly air masses prevailed, with a higher percentage of reduction in larger particles. The droplet mode particles, which dominated the sulfates and nitrates before the controls were implemented, were remarkably reduced in mass concentration after the control measures were implemented. Nevertheless, when the polluted southerly air masses prevailed, the local source control measures in Beijing did not effectively reduce the ambient sulfate concentration due to the enormous regional contribution from the North China Plain.

关键词： size distribution aerosol sulfate nitrate control effect Olympic Games

“3+1+2”选科模式下大学生高考改革满意度的群体差异

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教育与考试 2024年第3期 5-15页

作者：王新凤李传宗北京师范大学教育学部北京100875 北京师范大学中国教育政策研究院北京100875

2014年以来我国启动了新一轮考试招生制度改革,对第三批启动高考综合改革的江苏、湖南、湖北、广东、福建、河北、辽宁、重庆8省市高校学生问卷调查显示,“3+1+2”选科模式下的新高考生源大学生对高考改革的总体效果满意,直接利益相关... 详细信息

2014年以来我国启动了新一轮考试招生制度改革,对第三批启动高考综合改革的江苏、湖南、湖北、广东、福建、河北、辽宁、重庆8省市高校学生问卷调查显示,“3+1+2”选科模式下的新高考生源大学生对高考改革的总体效果满意,直接利益相关者对改革的获得感高。不同性别、年级、家庭背景、教育背景、选科偏好的学生的高考满意度存在显著差异。随着改革深入推进,高考改革政策宣传和优化效果显著,利益相关者对改革预期平稳,但高等学校尤其是普通本科高校应着力加强内涵建设,应对可能出现的生存危机。

关键词：新高考高考改革学生满意度选科制度