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Petrogenesis and Tectonic Implications of the Early Triassic Nianzi Adakitic Granite Unit in the Yanshan Fold and Thrust Belt:New Constraints from U-Pb Geochronology and Sr-Nd-Hf Isotopes

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 50-66页

作者： zhang huijun WU Chu HE Fubing WANG Biren CUI Yubin LIU Zhenghua YOU Shina DONG Jing Development and Research Center of the China Geological Survey Beijing 100037China Beijing Institute of the Geological Survey Beijing 100095China Institute of Disaster Prevention LangfangHebei 065201China

The Nianzi granite unit,which includes the Nianzi,Xiaolianghou and Xiawopu granitic intrusions,is a significant component of the northern part of the North China Craton(NCC)and is situated in the Yanshan fold and thrust belt(YFTB).However,there is still debate regarding the tectonic evolutionary history of the YFTB during the late Permian to Triassic period,specifically regarding the timing of subduction and collision between the NCC and the Paleo-Asian Ocean.The Nianzi granite unit exhibits unique petrological,geochronological and geochemical signatures that shed light on the tectonic evolutionary history of the YFTB.This study presents detailed petrology,whole-rock geochemistry,together with Sr-Nd isotopic,zircon U-Pb dating and Lu-Hf isotopic data of the granites within the Nianzi granite unit.Our findings demonstrate that the granites primarily consist of subhedral K-feldspar,plagioclase,quartz,minor biotite and hornblende,with accessory titanite,apatite,magnetite and zircon.Zircon U-Pb dating indicates that the Xiaolianghou granite was emplaced at 247.5±0.62 Ma.Additionally,the adakitic characteristics of the Nianzi,Xiawopu and Xiaolianghou granitic intrusions,such as high Sr and Ba contents and high ratios of Sr/Y and(La/Yb)N,combined with negative Sr-Nd and Lu-Hf isotopes(87Sr/86Sr)i=0.705681–0.7057433,εNd(t)=−21.98 to−20.97,zirconεHf(t)=−20.26 to−9.92,as well as the I-type granite features of high SiO_(2),Na_(2)O and K_(2)O/Na_(2)O ratios,enriched Rb,K,Sr and Ba,along with depleted Th,U,Nb,Ta,P and Ti,suggest that the Nianzi granitic unit was mainly derived from the partial melting of a thickened lower crust containing hydrous,calc-alkaline to high-K calc-alkaline,mafic to intermediate metamorphic rocks.In light of these parameters,we further integrate our data with previous studies and conclude that the Nianzi granitic unit was generated in a post-collisional extensional environment during the Early Triassic.

关键词： tectonic evolution zircon geochronology Sr-Nd-Hf isotopes Nianzi granite unit Yanshan fold and thrust belt

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Record-breaking summer-autumn drought in southern China in 2022:Roles of tropical sea surface temperature and Eurasian warming

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Science China Earth Sciences 2024年第2期67卷 420-431页

作者： Yuepeng HU Botao ZHOU huijun WANG Dapeng zhang Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing210044China

From summer to autumn in 2022,a severe drought lasted in southern China,posing serious effects on economic growth and ecological systems.This study explored the atmospheric circulations accounting for this persistent drought event.It shows that the drought in southern China during the summer of 2022 was strongly linked to the divergence of water vapor flux and descending motions,which were respectively caused by the anomalous anticyclone over the western North Pacific and the northward movement of the East Asian subtropical jet(EASJ).Differently,the atmospheric background responsible for the sustained drought in autumn is manly featured by a cyclonic circulation anomaly over the region from the Bay of Bengal to the South China Sea,which led to decreased moisture and descending motions in southern China.Further investigation suggests that the rarely strong surface warming over northern Eurasia and the extreme La Nina-like pattern over the tropical Pacific jointly resulted in the anomalous anticyclone over the western North Pacific and the northward shift of the EASJ in the summer of 2022,while the cyclonic circulation anomaly prevailing over the region from the Bay of Bengal to the South China Sea in autumn was largely attributed to the extremely negative anomalies of the tropical Indian Ocean sea surface temperature.

关键词： Summer-autumn drought Southern China Tropical sea surface temperature Eurasian warming

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Constructal design of a rectangular parallel phase change microchannel in a three-dimensional electronic device

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Science China(Technological Sciences) 2024年第5期67卷 1381-1390页

作者： zhang JiWen FENG huijun CHEN LinGen GE YanLin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan430205China College of Power Engineering Naval University of EngineeringWuhan430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan430205China

Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling fluid.Based on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II methods.The results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of TDED.By using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–0.45.The smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple requirements.The findings in this study can serve as theoretical guides for thermal designs of electronic devices.

关键词： constructal theory parallel microchannel evaporation phase change three-dimensional electronic device multi-objective optimization artificial neural network

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Improved remote sensing image target detection based on YOLOv7

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Optoelectronics Letters 2024年第4期20卷 234-242页

作者： XU Shuanglong CHEN Zhihong zhang Haiwei XUE Lifang SU huijun School of Integrated Circuit Science and EngineeringTianjin University of Technology Tianjin 300384China

Remote sensing images are taken at high altitude from above,with complex spatial scenes of images and a large number of target types.The detection of image targets on large scale remote sensing images suffers from the problem of small target size and target density.This paper proposes an improved model for remote sensing image detection based on you only look once version 7(YOLOv7).First,the small-scale detection layer is added to reacquire tracking frames to improve the network’s recognition ability of small-scale targets,and then Bottleneck Transformers are fused in the backbone to make full use of the convolutional neural network(CNN)+Transformer architecture to enhance the feature extraction ability of the network.After that,the convolutional block attention module(CBAM)mechanism is added in the head to improve the model’s ability of small-scale target.Finally,the non-maximum suppressed(NMS)of YOLOv7 algorithm is changed to distance intersection over union-non maximum suppression(DIOU-NMS)to improve the detection ability of overlapping targets in the network.The results show that the method in this paper can improve the detection rate of small-scale targets in remote sensing images and effectively solve the problem of high overlap and is tested on the NWPU-VHR10 and DOTA1.0 datasets,and the accuracy of the improved model is improved by 6.3%and 4.2%,respectively,compared with the standard YOLOv7 algorithm.

关键词： image network union

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Ti_(3)C_(2)T_(x) MXene/carbon composites for advanced supercapacitors:Synthesis,progress,and perspectives

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Carbon Energy 2024年第2期6卷 113-142页

作者： Yanqing Cai Xinggang Chen Ying Xu Yalin zhang huijun Liu Hongjuan zhang Jing Tang College of Materials Science and Engineering North China University of Science and TechnologyTangshanChina Hebei Iron and Steel Laboratory North China University of Science and TechnologyTangshanChina Songshan Lake Materials Laboratory DongguanChina Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghaiChina State Key Laboratory of Petroleum Molecular and Process Engineering(SKLPMPE) Sinopec Research Institute of Petroleum Processing Co.Ltd.BeijingChina Institute of Eco-Chongming ShanghaiChina

MXenes are a family of two-dimensional(2D)layered transition metal carbides/nitrides that show promising potential for energy storage applications due to their high-specific surface areas,excellent electron conductivity,good hydrophilicity,and tunable terminations.Among various types of MXenes,Ti_(3)C_(2)T_(x) is the most widely studied for use in capacitive energy storage applications,especially in supercapacitors(SCs).However,the stacking and oxidation of MXene sheets inevitably lead to a significant loss of electrochemically active sites.To overcome such challenges,carbon materials are frequently incorporated into MXenes to enhance their electrochemical properties.This review introduces the common strategies used for synthesizing Ti_(3)C_(2)T_(x),followed by a comprehensive overview of recent developments in Ti_(3)C_(2)T_(x)/carbon composites as electrode materials for SCs.Ti_(3)C_(2)T_(x)/carbon composites are categorized based on the dimensions of carbons,including 0D carbon dots,1D carbon nanotubes and fibers,2D graphene,and 3D carbon materials(activated carbon,polymer-derived carbon,etc.).Finally,this review also provides a perspective on developing novel MXenes/carbon composites as electrodes for application in SCs.

关键词： electrochemical performance MXene/carbon composites supercapacitors

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Acoustic carrier signal transmission technology and its potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear/gas-insulated transmission line

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High Voltage 2024年第2期9卷 287-295页

作者： Chen Chen Yutong zhang huijun Zhao Zongren Peng Qingyu Wang Xi'an Jiaotong University Xi'anChina

A wireless signal transmission technology based on acoustic carrier is proposed,which overcomes the limitation of electromagnetic signal shielding and shows great potential for in-site monitoring of sliding electrical contact used in gas-insulated switchgear(GIS)/gasinsulated transmission line(GIL).Here,the state parameter of the sliding electrical contact is modulated onto the frequency domain of an ultrasound wave.As a mechanical wave,the ultrasonic wave is immune to electromagnetic shielding,so that it could carry the sensing signal to penetrate the metal shielding layer and transmit to the external terminals of GIS/GIL.The principle and signal modulation process of the acoustic carrier based transmission system have been demonstrated in detail.Both simulation and experiment have been conducted to analyse the system characteristics as well as optimise the system configuration.As a proof-of-concept application,the in situ and on-line monitoring of the thermal rise of a slide electrical contact both in a current loading equivalent model and a prototype of GIS is demonstrated.Experimental results fit well with the physical process,and show a good measurement accuracy of 0.6%and tem-perature sensitivity of 400 Hz/℃.

关键词： electrical potential Acoustic

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Precipitation kinetics and strengthening of M23C6 in novel G115 martensitic steel:Utilizing secondary normalizing

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Progress in Natural Science:Materials International 2024年第2期34卷 396-407页

作者： Chengxian zhang Zhi Yuan Qiuzhi Gao Qingshuang Ma Hailian zhang Jing Bai Huijie zhang Liming Yu huijun Li School of Materials Science and Engineering Northeastern University School of Resources and Materials Northeastern University at Qinhuangdao School of Materials Science & Engineering Tianjin University School of Mechanical Materials and Mechatronic Engineering University of Wollongong

G115 martensitic steel is anticipated to be one of the preferred candidate materials in ultra-super critical(USC)power plants with steam temperatures above 650℃.Microstructure evolutions and mechanical properties of G115 martensitic steel after applying various heat treatment processes were investigated.The results demonstrate that the main precipitate in G115 martensitic steel after applying various heat treatment processes is M23C6 phase with Cr enrichment.The time required for M23C6 phase precipitation decreases with increasing secondary normalizing temperature and the extension in holding time according to its precipitation-temperature-time(PTT)curves.Volume fraction of M23C6 phase increases with increasing secondary normalizing temperature and holding time,which strengthens the inhibitory effect of precipitates on dislocations recovery and laths growth.Therefore,G115 martensitic steel can obtain the best mechanical properties after applying the highest secondary normalizing temperature and the longest holding time.In the current work,the excellent strength of G115 martensitic steel mainly derives from precipitates strengthening and laths strengthening.

关键词： G115 martensitic steel M23C6 phase Precipitation kinetics Secondary normalizing Strengthening mechanisms

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NO_(x) reduction against alkali poisoning over Ce(SO_(4))_(2)-V_(2)O_(5)/TiO_(2) catalysts by constructing the Ce^(4+)-SO_(4)^(2−)pair sites

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Chinese Chemical Letters 2024年第5期35卷 355-360页

作者： Shuangxi Li huijun Yu Tianwei Lan Liyi Shi Danhong Cheng Lupeng Han Dengsong zhang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringInternational Joint Laboratory of Catalytic ChemistryCollege of SciencesShanghai UniversityShanghai 200444China

Commercial V_(2)O_(5)-based catalysts have been successfully applied in NH_(3) selective catalytic reduction(NH_(3)-SCR)of NO_(x) from power stations,but their poor alkali-resistance restrains the wider application in nonelectrical industries.In this study,NO_(x) reduction against alkali poisoning over V_(2)O_(5)/TiO_(2) is greatly improved via Ce(SO_(4))_(2) modification.It has been originally demonstrated that Ce^(4+)-SO_(4)^(2−)pair sites play crucial roles in improving NO_(x) reduction against alkali poisoning over V_(2)O_(5)/TiO_(2) catalysts.The strong interaction between V species and Ce sites of Ce^(4+)-SO_(4)^(2−)pairs triggers the reaction between NH_(4)^(+) species and gaseous NO via Eley-Rideal(E-R)reaction pathway.After K-poisoning,the SO_(4)^(2−)sites of Ce^(4+)-SO_(4)^(2−)pairs as protective sites strongly bond with K and thus maintain the high reaction efficiency via the E-R reaction pathway.This work demonstrates an effective strategy to enhance NO_(x) reduction against alkali poisoning over catalysts via constructing Ce^(4+)-SO_(4)^(2−)pair sites,contributing to developing alkali-resistant SCR catalysts for practical application in nonelectrical industries.

关键词： Air pollution control Selective catalytic reduction NOx reduction Alkali poisoning Ce(SO_(4))_(2)

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Exploring noncoding variants in genetic diseases:from detection to functional insights

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Journal of Genetics and Genomics 2024年第2期51卷 111-132页

作者： Ke Wu Fengxiao Bu Yang Wu Gen zhang Xin Wang Shunmin He Mo-Fang Liu Runsheng Chen huijun Yuan Institute of Rare Diseases West China Hospital of Sichuan UniversityChengduSichuan 610041China Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiang 310024China Key Laboratory of RNA Biology Center for Big Data Research in HealthInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Molecular Biology State Key Laboratory of Cell BiologyShanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai 200031China

Previous studies on genetic diseases predominantly focused on protein-coding variations, overlooking the vast noncoding regions in the human genome. The development of high-throughput sequencing technologies and functional genomics tools has enabled the systematic identification of functional noncoding variants. These variants can impact gene expression, regulation, and chromatin conformation, thereby contributing to disease pathogenesis. Understanding the mechanisms that underlie the impact of noncoding variants on genetic diseases is indispensable for the development of precisely targeted therapies and the implementation of personalized medicine strategies. The intricacies of noncoding regions introduce a multitude of challenges and research opportunities. In this review, we introduce a spectrum of noncoding variants involved in genetic diseases, along with research strategies and advanced technologies for their precise identification and in-depth understanding of the complexity of the noncoding genome. We will delve into the research challenges and propose potential solutions for unraveling the genetic basis of rare and complex diseases.

关键词： Noncoding variation Genetic disease Research approach Challenge

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Lycium barbarum glycopeptide(wolfberry extract)slows N-methyl-N-nitrosourea-induced degradation of photoreceptors

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Neural Regeneration Research 2024年第10期19卷 2290-2298页

作者： Qihang Kong Xiu Han Haiyang Cheng Jiayu Liu huijun zhang Tangrong Dong Jiansu Chen Kwok-Fai So Xuesong Mi Ying Xu Shibo Tang Department of Ophthalmology Aier Eye HospitalJinan UniversityGuangzhouGuangdong ProvinceChina Department of Ophthalmology The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Guangdong-Hong Kong-Macao Institute of CNS Regeneration Key Laboratory of CNS Regeneration(Ministry of Education)Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Ophthalmology Guangzhou Panyu Central HospitalGuangzhouGuangdong ProvinceChina School of Stomatology Jinan UniversityGuangzhouGuangdong ProvinceChina Aier Academician Station ChangshaHunan ProvinceChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina State Key Laboratory of Brain and Cognitive Sciences Hong Kong Special Administrative RegionChina

Photoreceptor cell degeneration leads to blindness, for which there is currently no effective treatment. Our previous studies have shown that Lycium barbarum(L. barbarum) polysaccharide(LBP) protects degenerated photoreceptors in rd1, a transgenic mouse model of retinitis pigmentosa. L. barbarum glycopeptide(Lb GP) is an immunoreactive glycoprotein extracted from LBP. In this study, we investigated the potential protective effect of Lb GP on a chemically induced photoreceptor-degenerative mouse model. Wild-type mice received the following: oral administration of Lb GP as a protective pre-treatment on days 1–7;intraperitoneal administration of 40 mg/kg N-methylN-nitrosourea to induce photoreceptor injury on day 7;and continuation of orally administered Lb GP on days 8–14. Treatment with Lb GP increased photoreceptor survival and improved the structure of photoreceptors, retinal photoresponse, and visual behaviors of mice with photoreceptor degeneration. Lb GP was also found to partially inhibit the activation of microglia in N-methyl-N-nitrosourea-injured retinas and significantly decreased the expression of two pro-inflammatory cytokines. In conclusion, Lb GP effectively slowed the rate of photoreceptor degeneration in N-methyl-N-nitrosourea-injured mice, possibly through an anti-inflammatory mechanism, and has potential as a candidate drug for the clinical treatment of photoreceptor degeneration.

关键词： anti-inflammation inherited retinal diseases Lycium barbarum glycopeptide N-methyl-N-nitrosourea opsin photoreceptor reactive gliosis retinal degeneration retinitis pigmentosa rhodopsin

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