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Analyses on an electronic voltage transformer's failure by its resonance with very fast transient overvoltage and suppression

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High Voltage 2024年第1期9卷 150-162页

作者： Ruoyu Han Houda Zhu Qing Chen hongbin li Yue Tong linshan Han Yang Jiao School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhanChina China Electric Power Research Institute WuhanChina School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhanChina

As voltage measuring devices are widely used in the high voltage power system with a primary-secondary-fusion structure,electronic voltage transformers are directly connected to the primary conductor and would face much more serious electromagnetic environments than general secondary *** a result,they would still experience failures even when general protection measures are adopted to suppress overvoltages'*** address this issue,an innovative method is proposed after analyses are conducted on the resonance between a transformer and an *** this method,an air-cored coil is installed in a transformer to artificially shift its natural frequency and to dodge the high-frequency dominant component of a transient overvoltage,avoiding the aforementioned resonance and suppressing the secondary *** addition,simulations and laboratory tests are conducted to prove this method's validity.

关键词： transient resonance mentioned

Modeling and prediction of tribological properties of copper/aluminum-graphite self-lubricating composites using machine learning algorithms

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Friction 2024年第6期12卷 1322-1340页

作者： Huifeng NING Faqiang CHEN Yunfeng SU hongbin li Hengzhong FAN Junjie SONG Yongsheng ZHANG litian HU School of Electrical and Mechanical Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The tribological properties of self-lubricating composites are influenced by many variables and complex ***-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understanding of complex problems under the influence of multiple parameters,typically for how tribological performances and material properties *** of friction coefficients and wear rates of copper/aluminum-graphite(Cu/Al-graphite)self-lubricating composites with their inherent material properties(composition,lubricant content,particle size,processing process,and interfacial bonding strength)and the variables related to the testing method(normal load,sliding speed,and sliding distance)were analyzed using traditional approaches,followed by modeling and prediction of tribological properties through five different ML algorithms,namely support vector machine(SVM),K-Nearest neighbor(KNN),random forest(RF),eXtreme gradient boosting(XGBoost),and least-squares boosting(LSBoost),based on the tribology experimental *** demonstrated that ML models could satisfactorily predict friction coefficient and wear rate from the material properties and testing method variables ***,the LSBoost model based on the integrated learning algorithm presented the best prediction performance for friction coefficients and wear rates,with R^(2) of 0.9219 and 0.9243,*** importance analysis also revealed that the content of graphite and the hardness of the matrix have the greatest influence on the friction coefficients,and the normal load,the content of graphite,and the hardness of the matrix influence the wear rates the most.

关键词： self-lubricating composites machine learning(ML) tribological properties prediction

Application of geophysical well logs in solving geologic issues:Past,present and future prospect

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Geoscience Frontiers 2024年第3期15卷 85-118页

作者： Jin Lai Yang Su Lu Xiao Fei Zhao Tianyu Bai Yuhang li hongbin li Yuyue Huang Guiwen Wang Ziqiang Qin National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Department of Petroleum Engineering University of WyomingLaramieWY 82071USA

Geophysical well logs are widely used in geological fields,however,there are considerable incompatibilities existing in solving geological issues using well log *** review critically fills the gaps between geology and geophysical well logs,as assessed from peer reviewed papers and from the authors’personal experiences,in the particular goal of solving geological issues using geophysical well *** origin and history of geophysical logging are *** follows a review of the state of knowledge for geophysical well logs in terms of type of specifications,vertical resolution,depth of investigations and demonstrated *** the current status and advances in applications of geophysical well logs in fields of structural geology,sedimentary geology and petroleum geology are *** logs are used in structural and sedimentary geology in terms of structure detection,in situ stress evaluation,sedimentary characterization,sequence stratigraphy division and fracture *** logs can also be applied in petroleum geology fields of optimizing sweet spots for hydraulic fracturing in unconventional oil and gas *** well logs are extending their application in other fields of geosciences,and geological issues will be efficiently solved via well logs with the improvements of advanced well log *** work is required in order to improve accuracy and diminish uncertainties by introducing artificial *** review provides a systematic and clear descriptions of the applications of geophysical well log data along with examples of how the data is displayed and processed for solving geologic problems.

关键词： Geophysical well logs Sequence stratigraphy Source rock Unconventional oil and gas resources Artificial intelligence

Gut microbiota: a potential target for hyperuricemia and gout

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Food Science and Human Wellness 2024年

作者： Feiyan Zhao Shuying Yang Laiyu Kwok hongbin li Heping Zhang Zhihong Sun Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering Key Laboratory of Dairy Products Processing， Ministry of Agriculture and Rural Affairs Key Laboratory of Dairy Biotechnology and Engineering， Ministry of Education， Inner Mongolia Agricultural University Department of Rheumatology and Immunology， The Affiliated Hospital of Inner Mongolia Medical University， Inner Mongolia Key Laboratory for Pathogenesis and Diagnosis of Rheumatic and Autoimmune Diseases

Modern lifestyle and diet have increased the incidence rate of uric acid (UA) metabolism-related diseases like hyperuricemia (HUA) and gout， posing heavy economic burden to individual patients and their families and the society. Uric acid metabolism is a complex physiological process involving the kidney， intestine， and other organs. A number of factors together regulate UA metabolism， including genetics， diet， hormones， and the gut microbiota. This review summaries the gut microbiota features in subjects with HUA and gout， and the therapeutic effects of implementing microecological therapies (probiotics， prebiotics， or fecal microbiota transplant) that target modulate the gut microbiota and its downstream metabolism on the disease. Current evidence shows that these strategies are safe and promising in alleviate inflammation， reduce UA， and restoring a healthy gut microbiota in subjects with UA metabolism-related diseases. However， most clinical data are generated by animal studies. Therefore， we propose that vigorous human intervention trials should be conducted in the future to evaluate the therapeutic effects of microecological therapies in managing HUA and gout.

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Spatial structure regulation towards armor-clad five-membered pyrroline nitroxides catholyte for long-life aqueous organic redox flow batteries

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eScience 2024年第1期4卷 143-151页

作者： Hao Fan Kai liu Xudong Zhang Yunpeng Di Pan liu Jiaqi li Bo Hu hongbin li Mahalingam Ravivarma Jiangxuan Song State Key Laboratory for Mechanical Behavior of Materials Shaanxi International Research Center for Soft MatterSchool of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China Network Information Center Xi'an Jiaotong UniversityXi'an 710049China

Five-membered pyrroline nitroxides with high-potential is fascinating as catholyte for aqueous organic redox flow batteries(AORFBs),however,it suffers from a primary deficiency of insufficient stability due to ring-opening side *** we report a spatial structure regulation strategy by host-guest chemistry,encapsulating 3-carbamoyl-2,2,5,5-tetramethylpyrroline-1-oxyl(CPL)into hydrosoluble cyclodextrins(CDs)with an inclusion structure of N–O⋅head towards cavity bottom,to boost the solubility and cyclability of pyrroline nitroxides *** armor-clad CPL(CPL⊂HP-β-CD)catholyte in 0.05–0.5 M presents a battery capacity fade rate as low as 0.002%/cycle(0.233%/day)compared to the sole CPL in 0.05 M(0.039%/cycle or 5.23%/day)over 500 cycles in assembled *** optimized reclining spatial structure with N–O⋅head towards CD cavity bottom effectively inhibits the attack of Lewis base species on the hydrogen abstraction site in pyrroline ring,and thus avoids the ring-opening side reaction of pyrroline nitroxides.

关键词： Aqueous organic redox flow batteries Stabilization mechanism Spatial structure Five-membered pyrroline nitroxides Cyclodextrins

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试论“中华民族共同体”的概念与特质

中国文化研究 2024年第1期 2-9页

作者：李鸿宾中央民族大学历史文化学院

本文专就“中华民族共同体”这一概念进行解释。它指的是建基于中国范围内各民族之上的人们共同体,意味着诸民族存在着密切的共生关联,并以框架的方式呈现其整体性之塑造,这些构成了“中华民族共同体”之要旨。这一概念虽从当今索解,但... 详细信息

本文专就“中华民族共同体”这一概念进行解释。它指的是建基于中国范围内各民族之上的人们共同体,意味着诸民族存在着密切的共生关联,并以框架的方式呈现其整体性之塑造,这些构成了“中华民族共同体”之要旨。这一概念虽从当今索解,但数千年发展和演变的进程赋予了这一共同体以深厚之根基,以至于一旦涉及到她倘若缺少“历史”就无从得解。

关键词： “中华民族共同体” 概念特质解释

基于优选建模和深度置信网络的电压互感器误差定量评估方法

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电测与仪表 2024年第8期61卷 55-62,77页

作者：徐云武李红斌张传计华中科技大学电气与电子工程学院武汉430074

电压互感器(potential transformer,PT)是电力系统中电压测量的关键设备,对PT的计量误差进行在线评估将有助于维护电能贸易结算的公平公正,其中基于数据驱动的PT在线评估方法因其评估性能优越而具有良好的工程应用前景,但存在着未考虑... 详细信息

电压互感器(potential transformer,PT)是电力系统中电压测量的关键设备,对PT的计量误差进行在线评估将有助于维护电能贸易结算的公平公正,其中基于数据驱动的PT在线评估方法因其评估性能优越而具有良好的工程应用前景,但存在着未考虑建模数据中是否含有异常数据以及无法定量评估等问题。为此,文中提出了一种基于优选建模和深度置信网络的定量评估方法,该方法通过无监督聚类技术确定理想的建模数据集,并利用深度置信网络进行训练得到PT定量评估模型,进而对PT实时输出信号进行分析实现误差定量评估。实验表明,该方法可有效检测出建模数据中的异常数据,且准确监测0.2级PT的计量误差状态,实现在运PT计量性能的准确评估。

关键词：电压互感器建模数据异常检测优选建模深度置信网络定量评估

复杂地质条件下钢板桩引孔施工技术研究与应用

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科学技术创新 2024年第9期 107-110页

作者：李宏宾中交第三航务工程局有限公司厦门分公司福建厦门

本文以某项目工程为例,通过了解该项目地质特性,确定施工方案,重点从旋挖引孔、引孔灌砂、插打钢板桩、承台施工及钢板桩拆除等具体施工技术进行论述,最后对钢板桩围堰稳定性进行验算及监测,结果显示各杆件稳定性均符合要求,基坑水平位... 详细信息

本文以某项目工程为例,通过了解该项目地质特性,确定施工方案,重点从旋挖引孔、引孔灌砂、插打钢板桩、承台施工及钢板桩拆除等具体施工技术进行论述,最后对钢板桩围堰稳定性进行验算及监测,结果显示各杆件稳定性均符合要求,基坑水平位移监测数据达标,验证了该工艺的可行性。

关键词：硬塑地质钢板桩引孔插打技术效果分析

miR-7抑制剂治疗MRL/lpr小鼠的实验性研究

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中国免疫学杂志 2024年第4期40卷 680-685,692页

作者：达古拉王静王勇李鸿斌内蒙古医科大学附属医院风湿免疫科内蒙古自治区风湿病发病机制与免疫诊断重点实验室呼和浩特010000

目的:探讨miR-7抑制剂治疗MRL/lpr小鼠的疗效。方法:选取30只MRL/lpr小鼠,随机分为miR-7抑制剂(miR-7 antagomir)组、环磷酰胺(CTX)组和生理盐水(Saline)对照组,10只/组。MRL/lpr小鼠13周时开始治疗,以上药物分别连续给药5周。每周观察... 详细信息

目的:探讨miR-7抑制剂治疗MRL/lpr小鼠的疗效。方法:选取30只MRL/lpr小鼠,随机分为miR-7抑制剂(miR-7 antagomir)组、环磷酰胺(CTX)组和生理盐水(Saline)对照组,10只/组。MRL/lpr小鼠13周时开始治疗,以上药物分别连续给药5周。每周观察各组小鼠一般状况并称重,留取血清和尿液标本。EliSA检测13~17周三组小鼠血清ANA、抗ds-DNA抗体、C3水平,并检测上述各周三组小鼠尿蛋白水平。流式细胞术检测三组小鼠Tfh细胞比例变化。RT-PCR检测三组小鼠脾脏和淋巴结miR-7和PTEN mRNA表达水平。HE、PAS、PASM染色观察光镜下三组小鼠的肾脏病理情况。结果:治疗5周后,形态学方面:与Saline组相比,miR-7 antagomir组和CTX组小鼠一般状况良好,体质量随周龄增加而增加。血清学方面:miR-7 antagomir组和CTX组血清ANA和抗ds-DNA抗体较Saline组明显下降,补体C3水平明显上升,但两治疗组间上述指标差异均无统计学意义。细胞学方面:miR-7 antagomir组小鼠脾脏Tfh细胞比例明显低于Saline组。与Saline组比较,miR-7 antagomir组小鼠脾B细胞miR-7表达水平降低,PTEN mRNA表达水平升高。此外,miR-7 antagomir组和CTX组小鼠光镜下肾脏病理改变均较Saline组有所好转,但该两组间肾脏病理改变无明显差异。结论:miR-7可作为系统性红斑狼疮的潜在治疗靶点,miR-7 antagomir能够显示出与经典免疫抑制剂CTX相近的治疗效果,有效地改善了MRL/lpr小鼠的狼疮样疾病表现,延缓了病情进展。

关键词：系统性红斑狼疮 miR-7抑制剂磷酸酶和张力蛋白同源物环磷酰胺