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儿童家庭住宅中VOCs浓度及其来源分析

建筑科学 2024年第8期40卷 185-192页

作者：王丽芳李琼何丽娟 SUNDELL jan 张寅平华北科技学院建筑工程学院河北廊坊065201 内蒙古科技大学能源与环境学院内蒙古包头014010 清华大学建筑技术科学系北京100084

室内挥发性有机化合物(VOCs)是危害儿童健康的主要污染物之一。本文调查了包头市123户学龄前儿童家庭住宅内VOCs浓度水平及其可能的来源。该研究是全国性调研“中国室内环境与儿童健康研究(China,Children,Homes,Health,简称CCHH)”中... 详细信息

室内挥发性有机化合物(VOCs)是危害儿童健康的主要污染物之一。本文调查了包头市123户学龄前儿童家庭住宅内VOCs浓度水平及其可能的来源。该研究是全国性调研“中国室内环境与儿童健康研究(China,Children,Homes,Health,简称CCHH)”中的一部分。研究结果显示,16种VOCs(检出率超过30%)为本调查对象的主要污染物。除苯的检出率达100%,超标率为2.4%外,其他种类VOCs均未超标。TVOC浓度范围为3.20~1297.1μg/m^(3),超标率为5%。采暖期VOCs浓度显著高于非采暖期,9种芳香族化合物在不同装修年限下存在显著性差异。通过主成分分析发现4个因子与VOCs来源相关,分别是室外机动车尾气排放、室内溶剂的散发、室内地板或皮革抛光剂的散发、室内杀虫剂或除臭剂的使用,且与非参数检验方法(Kruskal-Wallis检验)结果一致。本研究为深入认识西部干燥地区家庭住宅室内VOCs污染控制及风险评估提供科学参考。

关键词：家庭住宅 VOCs 室内环境影响因素污染源

Complex ammonium oxidation demands visualized resolution

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Science Bulletin 2024年第16期69卷 2478-2482页

作者： Zhihao Chen Yonghong Wu jan Dolfing Shunyao Zhuang Baozhan Wang Dan Li Shan Huang Bruce E.Rittmann State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Zigui Three Gorges Reservoir Ecosystem Observation and Research Station of Ministry of Water Resources of the People’s Republic of ChinaYichang 443605China University of Chinese Academy of Sciences Beijing 100049China d College of Nanjing University of Chinese Academy of SciencesNanjing 211135China Faculty of Energy and Environment Northumbria UniversityNewcastle-upon-Tyne NE18QHUK Department of Microbiology College of Life SciencesNanjing Agricultural UniversityKey Laboratory of Agricultural and Environmental MicrobiologyMinistry of Agriculture and Rural AffairsNanjing 210095China College of Urban Construction Nanjing Tech UniversityNanjing 211816China Department of Civil and Environmental Engineering Princeton UniversityPrinceton NJ 08540USA Biodesign Swette Center for Environmental Biotechnology Arizona State UniversityTempe AZ 85287-5701USA

The nitrogen cycle plays a vital role in sustaining productive and healthy ecosystems,with the microbial nitrogen cycle being a focal point in agriculture and eco-environmental *** these microbially mediated processes is ammonium(NH_(4)^(+))oxidation,the gatekeeper of the nitrogen *** understanding of ammonium oxidation is continuously evolving,thanks to recent research breakthroughs like comammox,Feammox,and dirammox[1-6].The increasing complexity of ammonium oxidation necessitates more precise and well-focused research tools beyond those commonly used today.

关键词： ammonium breakthrough precise

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如何选择兼顾价值创造与激励的绩效指标

中国管理会计 2024年第1期 107-116页

作者： jan Bouwens 王玮坤(译) 宿文迪(译) 阿姆斯特丹商学院中欧国际工商学院

不恰当的绩效指标设计会损害企业价值,而合适的绩效指标可以指引和激励管理者创造价值。本文以分权制管理下的大型石油化工集团为例,讨论了企业分部绩效指标设计应考虑的问题。绩效考核指标的选择需要尽量满足一致性、灵敏度和精确度要... 详细信息

不恰当的绩效指标设计会损害企业价值,而合适的绩效指标可以指引和激励管理者创造价值。本文以分权制管理下的大型石油化工集团为例,讨论了企业分部绩效指标设计应考虑的问题。绩效考核指标的选择需要尽量满足一致性、灵敏度和精确度要求。完美的绩效指标并不存在,分权制管理下的企业集团需要考虑分部指标和集团目标的一致性,采用能及时、准确体现不同分部管理者贡献的指标。与晋升和奖金高度相关的指标也要强化监管,避免操控和舞弊。

关键词：绩效指标设计指标一致性指标灵敏度指标相关性指标操纵

亚热带山地森林木质藤本和共生树木枝条和叶片性状的分化

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Journal of Plant Ecology 2024年第1期17卷 17-32页

作者： Xiao-Long Bai Da Yang jan Sher Yun-Bing Zhang Ke-Yan Zhang Qi Liu Han-Dong Wen Jiao-Lin Zhang Martijn Slot CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303China University of Chinese Academy of Sciences Beijing 100049China Forest Ecology and Forest Management Group Wageningen University and Research Centre6700 AA WageningenThe Netherlands Yuanjiang Savanna Ecosystem Research Station Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYuanjiang 653300China Smithsonian Tropical Research Institute Apartado 0843-03092BalboaAnconRepublic of Panama

因缺少性状的比较,我们对亚热带山地森林木质藤本和树木的与生态适应策略有关的功能性状变异格局仍知之甚少。本文通过研究中国西南亚热带山地森林中不同叶片习性的33种植物(7种落叶和4种常绿木质藤本、10种落叶和12种常绿树木)的13个... 详细信息

因缺少性状的比较,我们对亚热带山地森林木质藤本和树木的与生态适应策略有关的功能性状变异格局仍知之甚少。本文通过研究中国西南亚热带山地森林中不同叶片习性的33种植物(7种落叶和4种常绿木质藤本、10种落叶和12种常绿树木)的13个性状的分化来填补此空白。研究结果表明,木质藤本的枝条木质部导管直径、理论导水率、比叶面积、叶片氮和磷含量显著高于树木,但其叶片干物质含量和氮磷比显著低于同域分布的树木,表明木质藤本采取获取的生态策略,具有更高效的枝条导水系统和生产力更强的叶片。与树木相比,木质藤本的导管直径变异更大,同时具有一些大导管和很多小导管,说明木质藤本具有较大的导管二型性。生长型解释了性状总变异的48.7%,叶片习性仅解释了3.8%的总变异,生长型和叶片习性之间没有显著的交互作用。此外,枝叶性状仅在树木中存在显著相关,木质藤本中不存在,表明亚热带木质藤本枝条的水力功能与叶片的性状是解耦的。上述结果表明,亚热带山地木质藤本和树木的枝条和叶片功能性状存在显著差异。加强对亚热带山地生态系统中木质藤本和树木生态策略差异机制的认识还需要深入研究。

关键词：功能性状叶片习性叶片形态木质藤本亚热带山地森林木质部解剖

Haplotype-based phylogenetic analysis and population genomics uncover the origin and domestication of sweetpotato

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Molecular Plant 2024年第2期17卷 277-296页

作者： Mengxiao Yan Ming Li Yunze Wang Xinyi Wang M-Hossein Moeinzadeh Dora G.Quispe-Huamanquispe Weijuan Fan Yijie Fang Yuqin Wang Haozhen Nie Zhangying Wang Aiko Tanaka Bettina Heider jan F.Kreuze Godelieve Gheysen Hongxia Wang Martin Vingron Ralph Bock Jun Yang Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai 201602China College of Life Sciences Chongqing Normal UniversityChongqing 401331China Biotechnology and Nuclear Technology Research Institute Sichuan Academy of Agricultural SciencesChengdu 610061China College of Life Sciences Shanghai Normal UniversityShanghai 200234China Department of Computational Molecular Biology Max Planck Institute for Molecular GeneticsIhnestraBe 63-7314195 BerlinGermany Department of Biotechnology Ghent University9000 GhentBelgium Guangdong Provincial Key Laboratory of Crops Genetics and Improvement Crop Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China Graduate School of Bioagricultural Sciences Nagoya UniversityChikusaNagoya 464-8601Japan international Potato Center(CIP) LimaPeru CAS Center for Excellence of Molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China Max-Planck-Institut fur Molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany

The hexaploid sweetpotato(lpomoea batatas)is one of the most important root crops ***,its genetic origin remains controversial,and its domestication history remains *** this study,we used a range of genetic evidence and a newly developed haplotype-based phylogenetic analysis to identify two probable progenitors of *** diploid progenitor was likely closely related to lpomoea ae-quatoriensis and contributed the B,subgenome,IbT-DNA2,and the lineage 1 type of chloroplast genome to *** tetraploid progenitor of sweetpotato was most likely *** 4x,which donated the B2 subgenome,IbT-DNA1,and the lineage 2 type of chloroplast *** most likely originated from reciprocal crosses between the diploid and tetraploid progenitors,followed by a subsequent whole-genome *** addition,we detected biased gene exchanges between the subgenomes;the rate of B,to B2 subgenome conversions was nearly three times higher than that of B2 to B subgenome *** analyses revealed that genes involved in storage root formation,maintenance of genome stabil-ity,biotic resistance,sugar transport,and potassium uptake were selected during the speciation and domestication of *** study sheds light on the evolution of sweetpotato and paves the way forimprovementofthiscrop.

关键词： sweetpotato origin gene conversion domestication IbT-DNA HPA

Planetary Homeostasis of Reactive Nitrogen Through Anaerobic Ammonium Oxidation

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Engineering 2024年第7期38卷 175-183页

作者： Guibing Zhu Bangrui Lan Shuci Liu Cameron M.Callbeck Shanyun Wang Liping Jiang Asheesh Kumar Yadav jan Vymazal Mike S.M.Jetten Ganlin Zhang Yongguan Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Department of Environment and Science Queensland GovernmentBrisbaneQLD 4102Australia Department of Environmental Sciences University of BaselBasel 4056Switzerland CSIR-Institute of Minerals and Materials Technology Bhubaneswar 751013India Faculty of Environmental Sciences Czech University of Life Sciences PraguePraha 16521Czech Republic Department of Microbiology Radboud UniversityNijmegen 6525 XZThe Netherlands Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The availability of nitrogen(N)is crucial for both the productivity of terrestrial and aquatic ecosystems ***,the overuse of artificial fertilizers and the energy required to fix nitrogen have pushed the global nitrogen cycle(N-cycle)past its safe operating limits,leading to severe nitrogen pollution and the production of significant amounts of greenhouse gas nitrous oxide(N2O).The anaerobic ammonium oxidation(anammox)mechanism can counteract the release of ammonium and N2O in many oxygenlimited situations,assisting in the restoration of the homeostasis of the Earth’s N *** this work,we looked into the characteristics of the anammox hotspots’distribution across various types of ecosystems *** hotspots are present at diverse oxic-anoxic interfaces in terrestrial systems,and they are most prevalent at the oxic-anoxic transition zone in aquatic *** on the discovery of an anammox hotspot capable of oxidizing ammonium anoxically into N2 without N2O by-product,we then designed an innovative concept and technical routes of nature-based anammox hotspot geoengineering for climate change,biodiversity loss,and efficient utilization of water *** 15 years of actual use,anammox hotspot geoengineering has proven to be effective in ensuring clean drinking water,regulating the climate,fostering plant and animal diversity,and enhancing longterm environmental *** sustainable biogeoengineering of anammox could be a workable natural remedy to resolve the conflicts between environmental pollution and food security connected to N management.

关键词： Biogeochemical N-cycle Oxic-anoxic interface Nature-based solution Biogeoengineering Nitrogen sustainable development

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适应大范围星场密度变化的恒星辨识与抑制

光学精密工程 2024年第1期32卷 111-124页

作者：杨禹凯谷健王建立刘俊池中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049 吉林省智能波前传感与控制重点实验室吉林长春130033 中国人民解放军63768部队陕西西安710200

大视场光学望远镜是中高轨目标搜索的重要设备,在搜索图像中除中高轨目标外还存在恒星目标,对恒星目标进行辨识与抑制是中高轨目标检测的必要环节之一。考虑银道面附近天区、曝光时间差异以及多云遮挡等因素的影响,图像中的星场密度变... 详细信息

大视场光学望远镜是中高轨目标搜索的重要设备,在搜索图像中除中高轨目标外还存在恒星目标,对恒星目标进行辨识与抑制是中高轨目标检测的必要环节之一。考虑银道面附近天区、曝光时间差异以及多云遮挡等因素的影响,图像中的星场密度变化区间非常大,传统的恒星辨识方法在计算准确性与实时性方面均存在局限性,导致恒星虚警、计算超时等情况的发生。为解决该问题,提出了一种基于惯性坐标时域相对不变性的恒星辨识与抑制方法。推导了地平坐标系与惯性坐标系的数学转换关系,并由此构建了恒星辨识模型;在不同的静态系统误差条件下,量化分析了恒星目标的惯性坐标时域相对不变性;最后,开展了恒星辨识与抑制算法的仿真与实验验证。仿真与实验结果表明:在时间间隔为10 s、静态系统误差为10″的条件下,恒星的惯性坐标最大相对差异为0.51″(赤经),0.16″(赤纬),其时域相对不变性满足恒星辨识需求,辨识过程完全不依赖星场密度。经100圈次中高轨目标实测图像验证,本文方法未出现恒星虚警及中高轨目标检测缺失的现象。

关键词：目标检测恒星辨识与抑制中高轨目标搜索惯性坐标系

Tigris River Water Quality Quantifying Using the Iraq Water Quality Index (IraqWQI) and Some Statistical Techniques

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Engineering（科研） 2024年第6期16卷 149-166页

作者： Nadhir Al-Ansari Salam Hussein Ewaid Ali Chabuk Salwan Ali Abed Mudhafar A. Salim jan Laue Riyadh M. Salih Department of Civil Environmental and Natural Resources Engineering Lule University of Technology Lule Sweden Technical College of Shatra Southern Technical University Basra Iraq Department of Environmental Engineering College of Engineering University of Babylon Babylon Iraq Department of Environment College of Science University of Al-Qadisiyah Diwaniyah Iraq Iraqi Organization for Conservation of Nature IOCN Baghdad Iraq National Center for Water Resources Management Ministry of Water Resources Baghdad Iraq

Evaluation of water quality is important for the management of water resources. The current study is focused on the interpretation of the water quality monitoring data of the Tigris River in Iraq by the application of the principal component analysis (PCA), cluster analysis (CA), and water quality index (WQI). Twelve water quality parameters were taken from 14 stations along the river Ca2+, Mg2+, Na+, K+, Cl−, SO42−, HCO3−, NO3−, TH, TDS, BOD5, and EC to apply the PCA and CA. The results show that the mean of all the parameters was under the standards except Ca2+, EC, Mg2+, TH, and SO42−. The amount of EC is the critical factor that affects the river water quality. The PCA obtained one principal component responsible for 97% of the variation caused by different pollution sources. The CA divided the river into three regions of sampling stations with similar water quality, the best in the north, and the worst in the far south. In this paper, the computer-automated tool (IraqWQI) was presented and evaluated, which has been developed by authors to classify and measure the quality of Iraqi surface water. The proposed index is of hundred degrees and includes six variables for drinking water quality Cl−, TH, TDS, COD, DO, and total coliform (TC) according to the Iraqi specifications. The result of the IraqWQI application showed a decrease in the water quality of the river and its suitability for drinking in the south of the country. The best value of the index was (81.48, Good) in Fishkhabour during winter, and the worst value was (46.23, Bad) in Qurnah during summer. The result of this study proved the success and importance of using statistical techniques and WQI as useful tools for the management, control, and conservation of surface water. .

关键词： Component Formatting Style Styling

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共情考试

科学新闻 2024年第4期 59-60页

作者： jan Philipp R?er 倪伟波德国维藤/黑尔德克大学

“哦，现在我明白了。”同事说，“这就是你在考试上这么努力的原因。”在与一位同事共进午餐时，我分享了自己多年前作为一名患有考试焦虑症的学生所经历的挣扎。她的话让我有点吃惊，但让我开始思考，为什么从7年前开始当教授以来，...

“哦，现在我明白了。”同事说，“这就是你在考试上这么努力的原因。”在与一位同事共进午餐时，我分享了自己多年前作为一名患有考试焦虑症的学生所经历的挣扎。她的话让我有点吃惊，但让我开始思考，为什么从7年前开始当教授以来，我一直把缓解学生考试前的紧张放在首位。我意识到她可能是有道理的：作为学生的经历有助于我理解作为一名教授能做些什么让口试尽可能透明、公平和包容。这需要一些额外的工作，但是值得。

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