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Role of interfacial electron transfer reactions on sulfamethoxazole degradation by reduced nontronite activating H_(2)O_(2)

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Journal of Environmental Sciences 2023年第2期124卷 688-698页

作者： Hao-jie cui Yaqi Ning CongWu Wei Peng Dong Cheng Lichu Yin Weijun Zhou Wenjuan Liao College of Resources and Environment Hunan Agricultural UniversityChangsha 410128China College of Environment Zhejiang University of TechnologyHangzhou 310014China

It has been documented that organic contaminants can be degraded by hydroxyl radicals(•OH)produced by the activation of H2O2 by Fe(II)-bearing clay.However,the interfacial electron transfer reactions between structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation and its effects on contaminant remediation are unclear.In this study,we first investigated the relation between•OH generation sites and sulfamethoxazole(SMX)degradation by activating H2O2 using nontronite with different reduction extents.SMX(5.2–16.9μmol/L)degradation first increased and then decreased with an increase in the reduction extent of nontronite from 22% to 62%,while the•OH production increased continually.Passivization treatment of edge sites and structural variation results revealed that interfacial electron transfer reactions between Fe(Ⅱ)and H2O2 occur at both the edge and basal plane.The enhancement on basal plane interfacial electron transfer reactions in a high reduction extent rNAu-2 leads to the enhancement on utilization efficiencies of structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation.However,the•OH produced at the basal planes is less efficient in oxidizing SMX than that of at edge sites.Oxidation of SMX could be sustainable in the H_(2)O_(2)/rNAu-2 system through chemically reduction.The results of this study show the importance role of•OH generation sites on antibiotic degradation and provide guidance and potential strategies for antibiotic degradation by Fe(Ⅱ)-bearing clay minerals in H2O2-based treatments.

关键词： Reduced nontronite Electron transfer Sulfamethoxazole degradation Reaction sites Hydroxyl radicals

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服务器RJ45网口常见电磁兼容问题分析

信息技术与信息化 2024年第1期 141-144页

作者：崔杰鲍乐梅王武军浪潮电子信息产业股份有限公司山东济南250014

服务器RJ45网口涉及GB/T9254.1-2021和GB/T9254.1-2021电磁兼容要求的多个测试项目。其中,电磁辐射、静电、浪涌等测试为常见容易出现问题的项目,在产品研发后期进行电磁兼容问题整改,所花费的时间和成本要比其他问题更昂贵。如果能在... 详细信息

服务器RJ45网口涉及GB/T9254.1-2021和GB/T9254.1-2021电磁兼容要求的多个测试项目。其中,电磁辐射、静电、浪涌等测试为常见容易出现问题的项目,在产品研发后期进行电磁兼容问题整改,所花费的时间和成本要比其他问题更昂贵。如果能在产品设计前期规避问题,则后期整改要更容易。结合服务器RJ45网口的拓扑结构,在通信链路中加入或预留足够的设计方案,能够使产品更好地通过电磁兼容测试。电磁辐射的共模噪声和时钟噪声可以通过网络变压器中的共模线圈进行抑制。静电问题则可以借助于连接器良好的多点搭接进行解决。雷击则涉及硬件电路上的防护设计以及PCB设计的优化进行防护。多种良好的设计方案共同施加,保证了服务器产品的顺利上市。

关键词：服务器 RJ45网口电磁兼容电磁辐射网口PCB设计

Kinetic characterization of a slow chemical exchange between two sites in N,N-dimethylacetylamide by CEST NMR spectroscopy

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Chinese Chemical Letters 2022年第9期33卷 4335-4338页

作者： Lixia Wang Jikun Li Junfeng Xiang jie cui Yalin Tang Beijing National Laboratory for Molecular Sciences(BNLMS) Center for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Nuclear magnetic resonance(NMR)spectroscopy has provided many powerful tools for the study of dynamic processes.Among the reported methods,chemical exchange saturation transfer(CEST)is more suitable for systems with slow exchange rates,and there will be promising in the detection and dynamic mechanism of metastable substances.It has been widely used in magnetic resonance imaging(MRI),however whether it is applicable in the field of chemical kinetics needs more examples.Here we studied,as a proof of concept,the kinetics of the slow chemical exchange between the two N-methyl protons of N,N-dimethylacetylamide(DMA),exploiting QUantifying Exchange using Z-spectrum(QUEZS)and QUantifying Exchange using Saturation Time(QUEST)methods.It turned out that both of QUEZS and QUEST could give the corresponding exchange rates,showcasing the capability of this method to provide accurate kinetic data under a range of temperatures.Our results clearly demonstrated the reliability of CEST-based techniques as a tool for dynamic kinetics by NMR.

关键词： Chemical exchange saturation transfer(CEST) Chemical exchange N,N-Dimethylacetylamid Bloch-Mc Connell equation Dynamic kinetics

Synthesis of fluorescent multisubstituted polyquinolines by cascade C–H activation-based polyannulations of isonicotinamides and diynes

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Science China Chemistry 2023年第4期66卷 1139-1149页

作者： Dongyang Fan Fei Zhang jie cui Dong Wang Ting Han Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen 518172China

The development of new and efficient polymerization strategies for the synthesis of multisubstituted fused heterocyclic polymers with attractive properties is of great significance.Herein,a rhodium-catalyzed polyannulation route is developed for the in situ generation of multisubstituted polyquinolines with efficient aggregate-state fluorescence.Based on the cascade C-H activation of isonicotinamides and their annulations with internal diynes,a series of high molecular weight polyquinolines are efficiently produced in high yields of up to 99%in a facile and atom-economical manner.Unlike conventional two-component stepwise polymerizations,these polyannulation reactions are tolerant to monomer non-stoichiometric conditions and proceed even more thoroughly in the presence of an excess amount of the isonicotinamide monomer.Benefiting from the unique multisubstituted polyquinoline structures,the obtained polymers show high thermal and morphological stability,useful aggregation-induced emission(AIE)properties,and tunable aggregated-state fluorescence behaviors.The AIE-active polyquinoline is demonstrated to be a good lysosome-specific fluorescent probe with low cytotoxicity and excellent photostability.

关键词： fused heterocyclic polymers polyannulation polyquinolines aggregation-induced emission bioimaging

Forward and backward secure searchable encryption with multi-keyword search and result verification

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Science China(Information Sciences) 2022年第5期65卷 270-272页

作者： jie cui Yue SUN Yan XU Miaomiao TIAN Hong ZHONG School of Computer Science and Technology Anhui University Institute of Physical Science and Information Technology Anhui University Anhui Engineering Laboratory of LoT Security Technologies Anhui University

Dear editor,Searchable encryption [1] is a new search method that not only protects personal privacy, but also searches over encrypted data. The multi-keyword scheme can search documents with more keywords so that the... 详细信息

关键词： Forward Security Backward Security Multi-keyword Search Verification Searchable Encryption

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井下有轨运输远程放矿监控系统的设计与应用

世界有色金属 2024年第8期 23-25页

作者：崔杰寿刘志旺王晓忠姜雅杰金川集团信息与自动化工程有限公司甘肃金昌737100 金川集团股份有限公司甘肃金昌737100

有轨运输电机车是有色金属矿山井下矿石转运的主要设备,受井下巷道结构复杂、网络基础设施薄弱等因素影响,需要投入大量人力在现场配合电机车司机完成相关运输任务,实际作业过程中存在操作人员劳动强度大、易发生机械伤害等诸多问题。... 详细信息

有轨运输电机车是有色金属矿山井下矿石转运的主要设备,受井下巷道结构复杂、网络基础设施薄弱等因素影响,需要投入大量人力在现场配合电机车司机完成相关运输任务,实际作业过程中存在操作人员劳动强度大、易发生机械伤害等诸多问题。金川集团信息与自动化工程公司通过对放矿及道岔控制进行自动化改造,并将视频监控、漏泄通讯、红区管控等系统有机结合,实现井下有轨电机车的远程放矿及无人值守,在有色矿山具有推广应用和借鉴价值。

关键词：有轨运输放矿道岔控制泄露通讯红区管控

Mn对铸态及均匀化态6082铝合金组织的影响

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材料热处理学报 2024年第6期45卷 33-41页

作者：崔振杰姜海昌张舵张汝梦牌君君贾娈娈滨州魏桥国科高等技术研究院山东省先进铝基材料与技术重点实验室山东滨州256600 中国科学院金属研究所中国科学院核用材料与安全评价重点实验室辽宁沈阳110016

采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、差示扫描量热法(DSC)和电导率测试仪等研究了Mn含量分别为0.7 mass%和0.5 mass%(分别命名为07Mn合金和05Mn合金)的6082铝合金铸态、均匀化态组织及析出行为。结果表明:铸态07Mn合金... 详细信息

采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、差示扫描量热法(DSC)和电导率测试仪等研究了Mn含量分别为0.7 mass%和0.5 mass%(分别命名为07Mn合金和05Mn合金)的6082铝合金铸态、均匀化态组织及析出行为。结果表明:铸态07Mn合金组织中形成了更粗大的鱼骨状结晶相,均匀化退火后,晶界处难溶结晶相转化为了微米级α-Al(Mn, Fe)Si相,并在晶内析出了纳米级的α-Al(Mn, Fe)Si相。07Mn合金中α-Al(Mn, Fe)Si相的析出激活能更低,从而析出了数量更多、尺寸更小的α-Al(Mn, Fe)Si相。通过电导率计算,确认了Mn元素会促进合金中α-Al(Mn, Fe)Si相的形核。

关键词： 6082铝合金 Mn含量结晶相弥散相 α-Al(Mn Fe)Si

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食物与动脉粥样硬化的孟德尔随机化研究

预防医学 2024年第6期36卷 483-486,490页

作者：刘伟林泉范宗静崔杰吴旸北京中医药大学东方医院心血管科北京100078

目的采用双样本孟德尔随机化(MR)法探讨食物与动脉粥样硬化的因果关系,为预防动脉粥样硬化提供参考。方法通过IEU OpenGWAS数据库收集16种食物(谷物、蔬菜、水果、肉类等)和4种类型动脉粥样硬化(冠状动脉粥样硬化、脑动脉粥样硬化、外... 详细信息

目的采用双样本孟德尔随机化(MR)法探讨食物与动脉粥样硬化的因果关系,为预防动脉粥样硬化提供参考。方法通过IEU OpenGWAS数据库收集16种食物(谷物、蔬菜、水果、肉类等)和4种类型动脉粥样硬化(冠状动脉粥样硬化、脑动脉粥样硬化、外周动脉粥样硬化和其他动脉粥样硬化)的研究数据,食物数据包括约50万名研究对象和9851867个单核苷酸多态性(SNP)位点,动脉粥样硬化数据包括约20万名研究对象和16380447个SNP。以食物为暴露变量,动脉粥样硬化为结局变量,主要采用逆方差加权法(IVW)分析因果关系。采用漏斗图和留一法进行敏感性分析。结果摄入干果与外周动脉粥样硬化(OR=0.195,95%CI:0.082~0.466)和其他动脉粥样硬化风险降低有关(OR=0.208,95%CI:0.095~0.452),摄入奶酪与外周动脉粥样硬化风险降低有关(OR=0.575,95%CI:0.380~0.870);摄入咖啡与冠状动脉粥样硬化风险升高有关(OR=1.645,95%CI:1.099~2.462),摄入酒精与其他动脉粥样硬化风险升高有关(OR=1.269,95%CI:1.032~1.561);未发现16种食物与脑动脉粥样硬化存在统计学关联。未发现水平多效性;任何单个SNP未对总体估计值产生明显影响;漏斗图未显示明显偏倚。结论摄入干果和奶酪是动脉粥样硬化的保护因素,摄入咖啡和酒精是危险因素。

关键词：动脉粥样硬化食物摄入孟德尔随机化关联

湖南省柑橘园土壤pH值空间变异特征、成因及养分有效性

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植物营养与肥料学报 2024年第4期30卷 717-730页

作者：徐章倩周卫军崔浩杰周雨舟商贵铎李敏岳晴晴湖南农业大学资源学院湖南长沙410128

[目的]研究湖南省柑橘园土壤pH值的空间变异特征、影响因素及主要养分的有效性,为减缓柑橘园土壤酸化,提升土壤肥力提供科学依据。[方法]本研究以湖南省38个柑橘重点县的15722个柑橘园土壤为对象,利用地统计学、相关性分析、结构方程模... 详细信息

[目的]研究湖南省柑橘园土壤pH值的空间变异特征、影响因素及主要养分的有效性,为减缓柑橘园土壤酸化,提升土壤肥力提供科学依据。[方法]本研究以湖南省38个柑橘重点县的15722个柑橘园土壤为对象,利用地统计学、相关性分析、结构方程模型等方法,探究了湖南省柑橘园土壤pH值的空间变异特征,分析了土壤pH值对地理、气候、土壤性质等因子的响应,并研究了土壤pH值对土壤氮、磷、钾有效性的影响。[结果]湖南省柑橘园土壤pH值范围为3.00~8.50,均值为5.58,变异系数为18.06%,空间变异为中等程度。最适合柑橘生长的弱酸性土壤面积占44.35%,而酸性、强酸性、中性和碱性土壤分别占48.92%、1.69%、4.95%和0.08%。通过Pearson相关性分析发现,土壤pH值与降水量呈显著正相关(P<0.05),与速效钾含量呈极显著正相关(P<0.01),而与气温、碱解氮和有效磷含量呈极显著负相关(P<0.01)。结构方程模型模拟结果表明,土壤类型与成土母质是解释土壤pH值空间变异的主导因子。除少量强碱性土壤中碱解氮和有效磷含量处于较低水平外,柑橘园土壤各酸度等级土壤中的碱解氮、有效磷和速效钾含量皆处于适宜水平。[结论]由于特有的土壤类型和成土母质,湖南省柑橘园超过一半(50.61%)的土壤处于过酸状态(酸性和强酸性)。湖南省柑橘园土壤速效氮、磷、钾养分含量基本处于适宜水平,因此,应重视改善土壤酸性。

关键词：柑橘园土壤 pH值空间特征成土母质地理因素速效养分