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潘家口水库机电设备安全管理浅析

海河水利 2024年第S1期 39-43页

作者：姜宇航张琢玥海河水利委员会引滦工程管理局天津300393

介绍了潘家口水库及该水库机电设备的现状,简述了水库主管单位根据水利安全生产风险管控“六项机制”出台的一系列机电设备安全管理办法。通过分析安全管理办法的内容、意义,既总结了当前办法收获的经验,又对未来优化和改善办法进行了展... 详细信息

介绍了潘家口水库及该水库机电设备的现状,简述了水库主管单位根据水利安全生产风险管控“六项机制”出台的一系列机电设备安全管理办法。通过分析安全管理办法的内容、意义,既总结了当前办法收获的经验,又对未来优化和改善办法进行了展望,有利于今后继续开展潘家口水库机电设备安全管理工作,对保障水库机电设备乃至大坝整体的安全有积极意义。

关键词：安全管理数据台账检查与反馈机制

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火场汽油检验鉴定基质干扰官能团的溯源研究

分析化学 2024年第3期52卷 389-406页

作者：张茜茜臧政哲金静殷果胡语嫣钱佩雯李秋璠梓蒋宇杭中国人民警察大学研究生院中国人民警察大学侦查学院

火场助燃剂检验鉴定的基质干扰一直是法庭科学领域研究的重点和难点。为进一步探究C=C是否为基质干扰官能团，采用气相色谱-质谱联用（GC-MS）技术和裂解气相色谱-质谱联用（Py-GC/MS）技术，分别从化学结构和裂解过程的角度定性分析加... 详细信息

火场助燃剂检验鉴定的基质干扰一直是法庭科学领域研究的重点和难点。为进一步探究C=C是否为基质干扰官能团，采用气相色谱-质谱联用（GC-MS）技术和裂解气相色谱-质谱联用（Py-GC/MS）技术，分别从化学结构和裂解过程的角度定性分析加氢处理（饱和丁二烯双键）前后的苯乙烯-丁二烯-苯乙烯嵌段共聚物（SBS）和苯乙烯-乙烯-丁烯-苯乙烯（SEBS）燃烧/裂解产物对汽油鉴定的影响，利用二者的烷基苯、茚满类和稠环芳烃类组分提取离子流色谱图（EICs）与汽油燃烧残留物对应的EICs的谱图相似度对两类材料的干扰程度进行定量分析。定性和定量分析结果均表明，SEBS对汽油鉴定的干扰较小：相较于SBS，在SEBS燃烧残留物中无法检出茚满、二甲基茚满及二甲基萘等特征组分，并且烷基苯、茚满类和稠环芳烃类特征组分的相对含量均明显减少，即SEBS造成“假阳性”干扰的程度更低；加载汽油混合燃烧后，SBS和SEBS残留物的特征组分相对峰面积比例与汽油燃烧残留物仍存在较大差异，容易造成“假阴性”的结论；SEBS裂解过程中产生的含双键结构的裂解产物更少。结合SBS和SEBS双键结构的差异和裂解产物的差异，验证了C=C结构与汽油鉴定中的基质干扰程度存在关联。本研究结果为进一步了解火场残留物检验鉴定中产生基质干扰的官能团提供了重要参考。

关键词：火场残留物分析基质干扰汽油鉴定碳碳双键结构苯乙烯-丁二烯-苯乙烯嵌段共聚物氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物

Intraspecific floral colour variation in three Pedicularis species

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Plant Diversity 2024年第2期46卷 274-279页

作者： Qiu-yu Zhang Zhe Chen hang Sun Yang Niu State Key Laboratory of Plant Diversity and Specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China

Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constancy is largely determined by the floral traits of co-flowering species.Both higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower constancy.However,previous studies mainly focused on interspecific difference,and the intraspecific variation(consistency)of floral traits received much less attention.We hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering congeners.We investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19communities composed of either single or multiple Pedicularis species.Colour was quantified using image-based colour analysis as perceived by pollinators.We found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees,implying strongly constrained by the visual selection by pollinators.Contrary to the hypothesis,there is no significant difference in intraspecific floral colour variation between different community contexts.It may be due to the relatively large interspecific floral colour differences of most co-flowering species.The influence of community context on intraspecific variation may be reflected in floral traits other than colours.

关键词： Flower constancy Floral colour variation Plantepollinator interactions Pollinator vision

Supporting-electrolyte-free electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,N-arylglycines and paraformaldehyde

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Chinese Chemical Letters 2024年第6期35卷 327-330页

作者： Hai-Yang Song Jun jiang yu-hang Song Min-hang Zhou Chao Wu Xiang Chen Wei-Min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

The H-bond promoted electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,Narylglycines and paraformaldehyde for the synthesis of various benzo[d]imidazo[1,5-b]isothiazole 5,5-dioxide derivatives under ... 详细信息

关键词： H-bond N-Arylglycines Paraformaldehyde Organic electro-synthesis Electrolyte-free

Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

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Journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： Yi jiang Ya Liu Xuantao Yi Peng Zeng Bohan Liao hang Zhou Jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy soils.We conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice plants.The main elements in RHA were Si (29.64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62 mg/kg.Soil pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2%RHA.RHA promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active one.RHA reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth stages.RHA increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in it.Cd and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,respectively.The decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to stems.Therefore,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

Treadmill exercise improves hippocampal neural plasticity and relieves cognitive deficits in a mouse model of epilepsy

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Neural Regeneration Research 2024年第3期19卷 657-662页

作者： hang yu Mingting Shao Xi Luo Chaoqin Pang Kwok-Fai So Jiandong yu Li Zhang Key Laboratory of CNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina State Key Laboratory of Brain and Cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina Department of Neurosurgery The First Affiliated Hospital of Bengbu Medical CollegeBengbuShandong ProvinceChina School of Psychology Shanghai University of SportShanghaiChina

Epilepsy frequently leads to cognitive dysfunction and approaches to treatment remain limited.Although regular exercise effectively improves learning and memory functions across multiple neurological diseases,its application in patients with epilepsy remains controversial.Here,we adopted a 14-day treadmill-exercise paradigm in a pilocarpine injection-induced mouse model of epilepsy.Cognitive assays confirmed the improvement of object and spatial memory after endurance training,and electrophysiological studies revealed the maintenance of hippocampal plasticity as a result of physical exercise.Investigations of the mechanisms underlying this effect revealed that exercise protected parvalbumin interneurons,probably via the suppression of neuroinflammation and improved integrity of blood-brain barrier.In summary,this work identified a previously unknown mechanism through which exercise improves cognitive rehabilitation in epilepsy.

关键词： blood-brain barrier cognition hippocampus interneurons long-term potentiation microglial cell neuroinflammation spatial memory temporal epilepsy treadmill exercise

转角二维量子材料中平带相关的新奇电子态物性

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物理学报 2022年第12期71卷 182-194页

作者：王仲锐姜宇航中国科学院大学材料科学与光电技术学院北京100049 中国科学院大学材料与光电研究中心北京100049

二维量子材料具有诸多新奇的电子态物性,又易受到外部因素的影响和调控,因此成为近年来凝聚态物理等研究领域的前沿课题之一.而当以不同的旋转角度和堆叠次序制备出二维量子材料的异质结时,莫尔超晶格的形成又进一步诱导了异质结电子能... 详细信息

二维量子材料具有诸多新奇的电子态物性,又易受到外部因素的影响和调控,因此成为近年来凝聚态物理等研究领域的前沿课题之一.而当以不同的旋转角度和堆叠次序制备出二维量子材料的异质结时,莫尔超晶格的形成又进一步诱导了异质结电子能带结构的重整化,从而形成电子平带结构,再结合外加电场、磁场、应力场等外部条件,即可实现对材料整体新奇物性的设计与调控.本文主要围绕转角石墨烯及过渡金属硫族化合物异质结中的相关研究展开讨论,包括与平带物理相关的强关联效应、非常规超导现象、量子反常霍尔效应、拓扑相以及电子晶体等行为,并对未来的研究发展进行了展望.

关键词：二维量子材料莫尔超晶格平带关联效应

Effect of Cr_(2)O_(3) on properties of CaO-SiO_(2)-Fe_(t)O-MgO system and dissolution behavior of lime

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Journal of Iron and Steel Research(International) 2024年第4期31卷 870-881页

作者： Shan-nan Li Jian-li Li yue yu hang-yu Zhu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The productivity of the chrome-containing semi-steel converter smelting process is directly affected by the slag-forming speed during the converter preliminary stage.The effects of Cr_(2)O_(3) content on the physicochemical properties of the CaO-SiO_(2)-Fe_(t)O-MgO system,such as melting temperature,solidification behavior,mineral composition,and lime dissolution rate,were studied.The results showed that the slag was an amorphous phase at 1500℃.When Cr_(2)O_(3) was added,Ca(Fe,Mg)Si_(2)O_(6) and spinel were formed in the slag.With the increase in Cr_(2)O_(3) content,the amount of spinel precipitation increased,and the dendritic FegO_(4) crystal gradually changed into the granular(Fe,Mg)(Fe,Cr)2O_(4) crystal.As the Cr_(2)O_(3) content increased from O to 2.91 wt.%,the melting temperature of the slag rose,and the melting range of the slag expanded slightly,but the lime dissolution rate did not change.When the Cr_(2)O_(3) content further increased to 9.09 wt.%,the melting temperature continued to rise,the melting range rapidly expanded,and the lime dissolution rate decreased.

关键词： Cr_(2)O_(3) Vanadium-titanium magnetite Converter Slag Lime dissolution

PEPFL:A framework for a practical and efficient privacy-preserving federated learning

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Digital Communications and Networks 2024年第2期10卷 355-368页

作者： Yange Chen Baocang Wang hang jiang Pu Duan yuan Ping Zhiyong Hong State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an710071China School of Information Engineering Xuchang UniversityXuchang461000China School of Telecommunications Engineering Xidian UniversityXi'an710071China Secure Collaborative Intelligence Laboratory Ant GroupHangzhou310000China Facility of Intelligence Manufacture Wuyi UniversityJiangmen529020China

As an emerging joint learning model,federated learning is a promising way to combine model parameters of different users for training and inference without collecting users’original data.However,a practical and efficient solution has not been established in previous work due to the absence of efficient matrix computation and cryptography schemes in the privacy-preserving federated learning model,especially in partially homomorphic cryptosystems.In this paper,we propose a Practical and Efficient Privacy-preserving Federated Learning(PEPFL)framework.First,we present a lifted distributed ElGamal cryptosystem for federated learning,which can solve the multi-key problem in federated learning.Secondly,we develop a Practical Partially Single Instruction Multiple Data(PSIMD)parallelism scheme that can encode a plaintext matrix into single plaintext for encryption,improving the encryption efficiency and reducing the communication cost in partially homomorphic cryptosystem.In addition,based on the Convolutional Neural Network(CNN)and the designed cryptosystem,a novel privacy-preserving federated learning framework is designed by using Momentum Gradient Descent(MGD).Finally,we evaluate the security and performance of PEPFL.The experiment results demonstrate that the scheme is practicable,effective,and secure with low communication and computation costs.

关键词： Federated learning Partially single instruction multiple data Momentum gradient descent ElGamal Multi-key Homomorphic encryption