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强还原处理对土壤中常见抗生素及其抗性基因的影响研究

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生态环境学报 2024年第7期33卷 1107-1116页

作者：林于蓝陈厚朴于文豪王宝英张杨张金波蔡祖聪赵军南京师范大学地理科学学院江苏南京210023 南京师范大学生命科学学院江苏南京210023 江苏省土壤利用与农业可持续发展工程研究中心江苏南京210023 江苏省地理信息资源开发和利用协同创新中心江苏南京210023

土壤中抗生素长期累积所引发的抗性致病菌富集以及抗性基因(Antibiotic resistance genes,ARGs)的传播扩散,已成为当前备受关注的环境问题。为研究强还原处理(Reductive soil disinfestation,RSD)对土壤中抗生素及其ARGs的影响,以常用... 详细信息

土壤中抗生素长期累积所引发的抗性致病菌富集以及抗性基因(Antibiotic resistance genes,ARGs)的传播扩散,已成为当前备受关注的环境问题。为研究强还原处理(Reductive soil disinfestation,RSD)对土壤中抗生素及其ARGs的影响,以常用且难降解的抗生素四环素、土霉素、磺胺嘧啶和磺胺甲恶唑所构建的质量分数为20 mg·kg^(-1)的抗生素混合污染土壤为研究对象,分别设置以玉米秸秆(2%,RCS)、甘蔗渣(2%,RSR)为有机物料的RSD处理,同时设置不处理对照,于处理第7、14、28天进行破坏性采样,利用高效液相色谱和荧光定量PCR技术分析RSD处理过程中抗生素质量分数及ARGs和可移动遗传元件(Mobile genetic elements,MGEs)丰度的变化。结果表明,RSD处理可有效降解土壤中的四环素类和磺胺类抗生素,处理28 d后磺胺类抗生素的降解率为45.2%-100%,优于四环素类的33.5%-57.2%;RSR处理对四环素和磺胺嘧啶的降解效果优于RCS处理,其降解率可达57.2%-64.8%,而RCS处理对土霉素的降解率可达44.7%;两种RSD处理对磺胺甲恶唑的降解率在14 d时即可达100%。RSD处理后土壤中ARGs绝对丰度显著增加,RCS处理的增加作用强于RSR处理;随处理时间延长,tetM、qacH等基因相对丰度在RSD处理中呈下降趋势,一定程度上表明ARGs增加带来的生态负面效应得到缓解。RSD处理可显著降低IS26基因的相对丰度,表明其能通过消减特定MGEs削弱ARGs水平转移能力。综上,RSD处理可有效降解土壤中四环素类和磺胺类抗生素,具有消减土壤中ARGs并降低其传播风险的潜力。研究结果可为解决土壤抗生素污染问题、降低ARGs扩散风险提供一定的理论与技术支持。

关键词：强还原土壤处理抗生素抗生素抗性基因可移动遗传元件降解效应

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纯锡材料超精密车削切削液的配比研究

工具技术 2024年第8期58卷 42-45页

作者：闫凯常艳艳马振增龚宇欣李金波于文涛哈尔滨工程大学机电工程学院

为实现超精密切削纯锡表面质量的优化,通过对多种类型切削液进行评估研究,确定切削纯锡材料的切削液类型为酒精与异构烷烃的混合物,就不同的切削液配比分别进行切削实验,利用白光干涉仪观测表面形貌以及表面粗糙度,分析产生的表面缺陷... 详细信息

为实现超精密切削纯锡表面质量的优化,通过对多种类型切削液进行评估研究,确定切削纯锡材料的切削液类型为酒精与异构烷烃的混合物,就不同的切削液配比分别进行切削实验,利用白光干涉仪观测表面形貌以及表面粗糙度,分析产生的表面缺陷以及表面粗糙度数据。实验结果表明,在相同的切削参数下,使用金刚石刀具超精密车削纯锡的最佳切削液配比为:酒精含量20%,异构烷烃切削液含量80%;使用硬质合金刀具超精密车削纯锡的最佳切削液配比为:酒精含量60%~80%,异构烷烃切削液含量20%~40%。

关键词：纯锡材料超精密切削表面粗糙度切削液

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气候变化的灾害效应与科学挑战

科学通报 2024年第2期69卷 286-300页

作者：王岩王昊崔鹏陈德亮唐金波欧廷海郝建盛王姣张国涛雷雨伍纯昊中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101 中国科学院水利部成都山地灾害与环境研究所中国科学院山地灾害与地表过程重点实验室成都610299 Department of Earth Sciences University of GothenburgGothenburg 40530Sweden

自然灾害是地球系统各圈层相互作用最剧烈的一种表现形式,对人类社会有着深远的影响.气候变化导致的温度升高和降雨增多对灾害发生的水源、物源、能量等条件都有所影响,致使自然灾害出现新特点和新趋势,灾害风险急剧增加;自然灾害间的... 详细信息

自然灾害是地球系统各圈层相互作用最剧烈的一种表现形式,对人类社会有着深远的影响.气候变化导致的温度升高和降雨增多对灾害发生的水源、物源、能量等条件都有所影响,致使自然灾害出现新特点和新趋势,灾害风险急剧增加;自然灾害间的相互作用变强,促使复合灾害和级联灾害风险均有明显上升.本文归纳总结了自然灾害在强度、频率、持续时间、触发时间与位置、规模或影响范围等方面的变化规律,阐述其对气候变化的响应机制,提出气候变化灾害风险的五大科学挑战,包括:气候变化驱动的圈层相互作用和内外动力耦合致灾机制、跨时空尺度灾害发育规律、极端事件信息感知与数据驱动的风险判识、灾害动力学与风险演化规律、灾害风险管理与韧性社会构建.积极主动地应对这些挑战有助于深化对地球系统的科学理解,适应全球变化,减小灾害风险.

关键词：气候变化自然灾害灾害效应响应机制科学挑战

Two-dimensional MX Dirac materials and quantum spin Hall insulators with tunable electronic and topological properties

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Nano Research 2021年第3期14卷 584-589页

作者： Yan-Fang Zhang jinbo Pan Huta Banjade Jie yu Hsin Lin Arun Bansil Shixuan Du Qimin Yan Institute of Physics&University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100190China Department of Physics Temple UniversityPhiladelphiaPA19122USA Institute of Physics “Academia Sinica”Taipei11529Taiwan Physics Department Northeastern UniversityBostonMA02115USA

We propose a novel class of two-dimensional(2D)Dirac materials in the MX family(M=Be,Mg,Zn and Cd,X=Cl,Br and I),which exhibit graphene-like band structures with linearly-dispersing Dirac-cone states over large energy scales(0.8–1.8 eV)and ultra-high Fermi velocities comparable to ***-orbit coupling opens sizable topological band gaps so that these compounds can be effectively classified as quantum spin Hall *** electronic and topological properties are found to be highly tunable and amenable to modulation via anion-layer substitution and vertical electric *** structures of several members of the family are shown to host a Van-Hove singularity(VHS)close to the energy of the Dirac *** enhanced density-of-states associated with these VHSs could provide a mechanism for inducing topological *** presence of sizable band gaps,ultra-high carrier mobilities,and small effective masses makes the MX family promising for electronics and spintronics applications.

关键词： two-dimensional Dirac materials density functional theory topological properties

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科研建筑电力负荷密度研究

建筑电气 2024年第5期43卷 51-56页

作者：张晋波钱澄清于思淼韩建磊中科院建筑设计研究院有限公司北京市100086 北京电科能源管理有限公司北京市100190

通过对中国科学院科研院所集中的北京市中关村和奥运村区域内数十家单位的电力负荷进行深入调查研究,结合有关单位运行维护的电力监测平台数据,通过数据统计、处理和分析,设计流程复盘、设计参数验算等方法,辅以科研院所实地走访等手段... 详细信息

通过对中国科学院科研院所集中的北京市中关村和奥运村区域内数十家单位的电力负荷进行深入调查研究,结合有关单位运行维护的电力监测平台数据,通过数据统计、处理和分析,设计流程复盘、设计参数验算等方法,辅以科研院所实地走访等手段,从建设单位和设计单位共同关注的科研建筑“怎么算负荷,装机装多大”入手,针对科研建筑电力负荷密度的合理取值作出探索。

关键词：科研建筑节能减碳电力负荷峰值负荷密度装机负荷密度需要系数负荷构成负载率

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一种联合空域监管系统设计

计算机与网络 2024年第2期50卷 123-130页

作者：于健齐小谦张凯王庆楠谷金波中国电子科技集团公司第五十四研究所中华通信系统有限公司河北分公司河北省智能化信息感知与处理重点实验室

面向适应多样化联合行动样式和空域资源敏捷性使用需求，提出了一种联合空域监管系统设计方法。系统性介绍了空域监管系统能力特征、技术架构模型与功能分类，研究了空域实时数据处理、空域动态监视、空域监管决策等关键技术。对系统的... 详细信息

面向适应多样化联合行动样式和空域资源敏捷性使用需求，提出了一种联合空域监管系统设计方法。系统性介绍了空域监管系统能力特征、技术架构模型与功能分类，研究了空域实时数据处理、空域动态监视、空域监管决策等关键技术。对系统的关键技术内容及解决措施进行了重难点设计，提出了切实可行的解决方案，能够有效解决当前空域监管缺少科学、高效技术手段的突出问题，为实现全域全程空域资源综合监管机制提供了系统性基础模型和技术指导，为构建联合行动空域监管体系指明了发展方向。

关键词：空域监管空域协调冲突检测

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Tuning parallel symbolic execution engine for better performance

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Frontiers of Computer Science 2018年第1期12卷 86-100页

作者： Anil Kumar KARNA jinbo DU Haihao SHEN Hao ZHONG Jiong GONG Haibo yu Xiangning MA: Jianjun ZHAO Department of Computer Science Shanghai Jiao Tong University Shanghai 200240 China School of Software Shanghai Jiao Tong University Shanghai 200240 China Intel Asia-Pacific Research and Development Ltd. Shanghai 200240 China Department of Advanced Information Technology Kyushu University Fukuoka 819-0395 Japan

Symbolic execution is widely used in many code analysis, testing, and verification tools. As symbolic execu- tion exhaustively explores all feasible paths, it is quite time consuming. To handle the problem, researchers have par- alleled existing symbolic execution tools （e.g., KLEE）. In particular, Cloud9 is a widely used paralleled symbolic exe- cution tool, and researchers have used the tool to analyze real code. However, researchers criticize that tools such as Cloud9 still cannot analyze large scale code. In this paper, we con- duct a field study on Cloud9, in which we use KLEE and Cloud9 to analyze benchmarks in C. Our results confirm the criticism. Based on the results, we identify three bottlenecks that hinder the performance of Cloud9： the communication time gap, the job transfer policy, and the cache management of the solved constraints. To handle these problems, we tune the communication time gap with better parameters, modify the job transfer policy, and implement an approach for cache management of solved constraints. We conduct two evalua- tions on our benchmarks and a real application to understand our improvements. Our results show that our tuned Cloud9 reduces the execution time significantly, both on our bench- marks and the real application. Furthermore, our evaluation results show that our tuning techniques improve the effective- ness on all the devices, and the improvement can be achievedupto five times, depending upon a tuning value of our ap- proach and the behaviour of program under test.

关键词： code analysis symbolic execution parallelizingsymbolic execution KLEE Ctoud9

Effects of Annealing Temperature on the Properties of Copper Films Prepared by Magnetron Sputtering

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Journal of Wuhan University of Technology(Materials Science) 2015年第1期30卷 92-96页

作者：刘一鸣 ZHANG Jianjun ZHANG Wanggang 梁伟 yu Bin XUE jinbo College of Materials Science and Engineering Taiyuan University of Technology Shanxi Institute of Analytical Science

Copper oxide thin films were prepared by a direct-current magnetron sputtering method followed by a thermal annealing treatment at 100-500 ℃. The obtained films were characterized by X-ray diffraction, UV-vis absorption spectroscopy, scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. With the increase of the annealing temperature, it was found that the films transformed sequentially from amorphous to single-phase Cu （100℃）, mixed-phase of Cu and Cu2O （150 ℃）, single-phase Cu2O （200 ℃）, then to mixed-phase of Cu2O and CuO （300 ℃）, and finally to single-phase CuO （400 - 500 ℃）. Further analyses indicated that the Cu/Cu2O thin films and the Cu：O thin films presented no further oxidation even on the surface in air atmosphere. Additionally, the visible-light photocatalytic behavior of the copper oxide thin films on the degradation of methylene blue （MB） was also investigated, indicating that the films with pure Cu2O phase or Cu/Cu2O mixed phases have excellent photocatalytic efficiencies.

关键词： copper oxide thin films magnetron sputtering thermal annealing

Typical synergistic effect of graphite nanoplatelets and carbon nanotubes and its influence on polymer-based dielectric composites

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High Voltage 2016年第4期1卷 140-145页

作者： Hang Zhao Minhao Yang Delong He yu Liu Jintao Bai Hui Wang Haowei Chen jinbo Bai Laboratoire Mécanique des Sols Structures et MatériauxCNRS UMR 8579Ecole CentraleSupelecUniversitéParis SaclayGrande Voie des Vignes92290Chatenay-MalabryFrance State Key Lab Incubation Base of Photoelectric Technology and Functional Materials International Collaborative Center on Photoelectric Technology and Nano Functional MaterialsNorthwest UniversityXi’an 710069People’s Republic of China

Graphite nanoplatelets(GNPs)with their intrinsic two-dimensional structure make an excellent compromise of advantages of both graphite and *** to their outstanding inherent properties,GNPs have been widely used as the functional fillers to improve certain performances of polymer-based ***,the multi-layer stacked construction of GNPs could form aggregations easily,which limits their application in polymer-based dielectric ***,the authors exhibit a polydimethylsilicone(PDMS)-based nanocomposite which loading equivalent carbon nanotubes(CNTs)and GNPs as co-loading fillers,whose dielectric properties are improved *** composites were fabricated through a highly-shearing mechanical mixing *** the mixing process,both intrinsic CNTs entanglements and GNPs stacked aggregation could be ameliorated due to the interaction between these two types of *** with the GNPs solely loaded composites,a small quantity of CNTs addition endows GNPs/CNTs/PDMS ternary composites with a significantly decreased percolation threshold(f_(c)∼1.7 vol.%).Both GNPs and CNTs,these two representative conductive carbon constructions with high aspect ratios are able to effectively enhance the establishing efficiency of internal conductive network inner *** results indicate that the development of internal conductive network and dielectric performance of nanocomposites are able to be optimised through the strategy of taking advantage of the synergistic effect of multi-type fillers reasonably.

关键词： composites dielectric carbon