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U–Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton

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Chinese Science Bulletin 2008年第18期53卷 2828-2839页

作者： DIWU ChunRong SUN Yong YUAN HongLin WANG hongliang ZHONG XingPing liu XiaoMing State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China

In situ U-Pb dating and Lu-Hf isotopic analysis were carried out for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southern margin of the North China Craton (NCC). The re- sults provide further constraints on the crustal formation and evolution history of NCC. Four 207Pb/206Pb age populations were obtained from 99 analyses, with clusters at ~3.40 Ga, 2.77―2.80 Ga, ~2.50 Ga and 2.34 Ga, respectively. The 3.40 Ga old zircons have similar Hf isotopic compositions to those from Ar- chean rocks in the Jidong and Anshan areas of NCC. However, crustal remnants older than 3.6 Ga have been identified in the southern margin of NCC, the South China Craton, the northwestern part of the Qinling Orogen and its adjacent area. Thus, it is not easy to trace the source rock from which the 3.40 Ga detrital zircons were derived. It can be inferred that the crustal remnants older than 3.40 Ga might have been widely distributed in the North China Craton. The 2.77―2.80 Ga zircons make up a relatively small proportion and have the highest εHf (t) values (up to 6.1±1.6), consistent with the Hf isotopic composition of the depleted mantle at 2.83 Ga. Their single-stage Hf model age of 2.83 Ga is close to their crystallized age, suggesting that their source rocks were extracted from the contemporaneous depleted mantle. The ~2.50 Ga zircon grains constitute about 85% of the total grain population and their Hf isotopic compositions indicate major growth of juvenile crust at ~2.50 Ga but minor reworking of ancient crust. The youngest zircon dated in this study gave an U-Pb age of 2337±23 Ma, which can be considered the maximum depositional age of the formation of the Songshan Group.

关键词：锆石中国北方铪同位素地质探测

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Finite-time Control of Sampled-data Systems

Finite-time Control of Sampled-data Systems

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第25届中国控制与决策会议

作者： hongliang liu Huibo Zhou Shan Ding Peichen Wang Faculty of Mathematics Science Harbin Normal University Center of Control Theory and Guidance Technology Harbin Institute of Technology

ISBN: (纸本)9781467355339

Finite-time control of sampled-data systems are addressed. A kind of Lyapunov-Krasovskii function-like function is proposed, whose derivative does not need to be negative definite. Based on input-delay approach and free-weight matrix technologies, sufficient conditions which can ensure finite-time stability （FTS） for the resulted closed-loop system with rapid time-vary delay are given in linear matrix inequalities （LMIs）. And then in virtue of the results on finite-time stability, the state feedback controller is designed. These conditions are given in terms of LMIs and are delay-dependent.

关键词： Sampled-data systems input-delay approach finite time control LMI

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Terrestrial water storage variation in Hebei plain area of China,based on ground surface gravimetry

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Geodesy and Geodynamics 2021年第3期12卷 190-196页

作者： Hongtao Hao hongliang liu Xinlin Zhang Jin Wei Bin Zhao Minzhang Hu Key Laboratory of Earthquake Geodesy Institute of SeismologyCEAWuhan430071China Gavitation and Earth Tide National Observation and Research StationWuhan430071China Hubei Earthquake Administration Wuhan430071China Mobile Survey Team of Hebei Earthquake Agency Baoding071000China

Variation of terrestrial water storage in the Hebei plain area from March 2010 to June 2014 was studied using ground gravimetry combined with vertical displacement data from the Global Navigation Satellite *** show that observed gravity variation in this area increased continuously,basically reflecting a trend toward land *** the effect of this subsidence removed,a dominantnegative change in gravity variation was evident,reflecting an average rate of decrease in terrestrial water in this area of 0.10±0.053 m/y,and this is equivalent to a volume of 81.5±43.2×108 m^(3)and is consistent with the spatial distribution of groundwater change from measured hydrologic *** results can be an essential reference and supplement for the study of terrestrial water variation in the Hebei plain area,and indicate that ground surface gravimetry can be used as an important mean for studying changes in terrestrial water.

关键词： Hebei plain area Gravity variation Terrestrial water storage variation Ground surface gravimetry Land subsidence

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MED4 gene positively affects preadipocyte differentiation in Chinese red steppe cattle

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BIOCELL 2023年第9期47卷 2115-2123页

作者： MINGHONG WEI CHENG XIAO JIAN WU LIHONG QIN hongliang liu YANG CAO YUMIN ZHAO Institute of Animal Biotechnology Jilin Academy of Agricultural SciencesGongzhuling136100China Institute of Muscle Biology and Growth Research Institute for Farm Animal Biology(FBN)Dummerstorf18196Germany Key Laboratory of Beef Cattle Genetics and Breeding Ministry of Agriculture and Rural AffairsGongzhuling136100China

Background:The regulatory genes related to lipid metabolism affect the intramuscular fat(IMF)content and improve meat quality *** Complex Subunit 4(MED4),a vitamin D receptor protein,affects vitamin D,livestock growth,carcass traits,and triglyceride ***,the physiological function of the MED4 gene on bovine adipocyte differentiation remains ***:This study explored the function of the MED4 gene in preadipocyte differentiation in Chinese Red Steppe *** overexpression plasmid and the interference sequences of the MED4 gene were constructed to detect the effects of the MED4 gene on adipogenesis and biomakers using quantitative polymerase chain reaction and western ***:The MED4 gene had significantly high expression during preadipocyte differentiation(p<0.05).Overexpression of the MED4 gene increased the expression of the PPARγgene,a preadipocyte differentiation biomarker,improved cellular lipid droplets and triglycerides accumulation,and positively accelerated adipocyte maturation(p<0.05).Interference of the MED4 gene can negatively regulate preadipocyte ***:This study showed that the MED4 gene may affect the preadipocyte differentiation and adipogenesis in Chinese Red Steppe cattle by regulating the PPARγgene.

关键词： Chinese red steppe cattle MED4 PPARγ Predipocyte differentiation Lipid metabolism Meat quality trait

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Review of challenges and strategies for balanced urban-rural environmental protection in China

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Frontiers of Environmental Science & Engineering 2015年第3期9卷 371-384页

作者： Beidou XI Xiaoguang LI Jixi GAO Ying ZHAO hongliang liu Xunfeng XIA Tianxue YANG Lieyu ZHANG Xuan JIA State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China School of Environment Beijing Normal University Beijing 100875 China Nanjing Institute of Environmental Sciences of State Environmental Protection Administration Nanjing 210042 China

With the rise of environmentalism in China, great efforts have been devoted to environmental protec- tion over the past several decades. Compared with urban environmental protection, rural environmental protection has not been attached enough importance in China due to the dual-track structure of socio-economic development. As a result, rural China is shouldering disproportionally heavy environmental burdens partly because of the differences and biases between urban and rural environmental protection seen in environmental policies, environ- mental rights and interests, environmental protection investment, and the environmental protection awareness of people. To eliminate the gap between rural and urban environmental protection, and achieve the goal of ＂balanced urban-rural environmental protection＂（BUREP）, government should consider mapping out proper policies and strategies. In this paper we put forward an innovative strategy of BUREP against the background of China＇s urban-rural environmental protection. First, we review the current status of rural environmental protection status and its challenges compared with urban environ- mental protection in China. Secondly, we analyzed the main driving factors and reasons deeply, and then we put forward the BUREP strategy base on the unequal status between urban and rural environment. Finally, we proposed the framework of BUREP. This study may serve as a scientific reference regarding decision-making in coordinating urban and rural environmental protection and in constructing the new countryside of China.

关键词： urban environment rural environment,balanced urban--rural environmental protection framework of balanced urban-rural environmental protection (BUREP)

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A duplex TaqMan probe-based real-time PCR method for rapid detection and differentiation of the classical and VB strains of human immunodeficiency virus

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Science China(Life Sciences) 2024年第1期67卷 208-210页

作者： Aiping Wang Haili Wang Jianguo Zhao Yumei Chen hongliang liu Peiyang Ding Yan Niu Gaiping Zhang Longhu Laboratory Zhengzhou 450046China School of Advanced Agricultural Sciences Peking UniversityBeijing 100871China

Dear Editor,Human immunodeficiency virus(HIV)is a lentivirus that,if left untreated,can lead to acquired immunodeficiency syndrome(AIDS).The virus can be divided into two types based on genetic differences:HIV-1 and ***-1 is widely distributed worldwide and is the primary strain responsible for the global AIDS epidemic due to its high replication capacity,greater likelihood of transmission,and more severe clinical symptoms(Oeschger et al.,2021).

关键词： immunodeficiency untreated

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Circular cladding waveguides in Pr:YAG fabricated by femtosecond laser inscription:Raman,luminescence properties and guiding performance

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Opto-Electronic Advances 2021年第2期4卷 12-18页

作者： Quanxin Yang hongliang liu Shan He Qingyu Tian Bin Xu Pengfei Wu Institute of Modern Optics Nankai UniversityTianjin 300350China Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Tianjin 300350China Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Tianjin 300350China Department of Electronic Engineering Xiamen UniversityXiamen 361005China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

We report on the fabrication of circular cladding waveguides with cross-section diameters of 60−120μm in Pr:YAG crystal by applying femtosecond laser *** fabricated waveguides present 2D guidance on the cross-section and fairly low propagation *** high-order guiding modes are observed in waveguides with different *** simulation results reveal the origin of a specific kind of guiding *** micro-Raman(μ-Raman)experiments demonstrate the modification effects in femtosecond laser affected areas and ascertain the refractive index induced guiding *** addition,luminescence emission properties of Pr3+ions at waveguide volume are well preserved during the femtosecond laser inscription process,which may result in a potential high-power visible waveguide laser.

关键词： femtosecond laser inscription cladding waveguides Pr:YAG crystal luminescence emission

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Co/Cu多层膜沉积过程中结构和形貌的变化

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中国科学：技术科学 2016年第6期46卷 586-592页

作者：刘红亮陈冷北京科技大学材料科学与工程学院北京100083

从原子结合能和位错生成能入手,分别计算了在Co基底上沉积Cu薄膜和在Cu基底上沉积Co薄膜时,薄膜结构随沉积厚度增加所发生的变化.结果表明,在{100}纤维织构的Co基底上沉积Cu薄膜,当薄膜厚度达到3.33 nm时会在薄膜与基底界面产生错配位错... 详细信息

从原子结合能和位错生成能入手,分别计算了在Co基底上沉积Cu薄膜和在Cu基底上沉积Co薄膜时,薄膜结构随沉积厚度增加所发生的变化.结果表明,在{100}纤维织构的Co基底上沉积Cu薄膜,当薄膜厚度达到3.33 nm时会在薄膜与基底界面产生错配位错,且随薄膜厚度增加,错配位错密度逐渐增大.在{100}纤维织构Cu基底上沉积Co薄膜,当薄膜厚度达到4.90 nm时,薄膜生长模式会由层状向岛状转变,薄膜为fcc结构.当厚度超过12.64 nm后会出现hcp结构.计算结果与实验得出的结论基本相符.

关键词：巨磁电阻薄膜厚度位错择优取向

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Compact 1×3 waveguide beam splitters with variable splitting ratios in LiNbO_(3) crystal fabricated by femtosecond laser direct writing

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Chinese Optics Letters 2024年第9期22卷 37-41页

作者： Menghan Yu Siwen Ai Yuanliu Chen Feng Chen hongliang liu Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Institute of Modern OpticsNankai UniversityTianjin 300350China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China

In this Letter,waveguide beam splitters(1×3)with type I modifications are fabricated in a LiNbO_(3) crystal by femtosecond laser direct *** influence of the relative positions of three sub-waveguides on power splitting ratios are investigated in detail and the corresponding output intensities as functions of the relative positions in the numerical simulation are plotted,which are in good accordance with the experimental *** addition,the waveguide beam splitter with a 1:1:1 splitting ratio is fabricated by changing the relative widths of the three *** performances at 532 nm are measured and analyzed by a typical end-face coupling *** simulation and experimental results demonstrate that the beam splitting ratio of the waveguide splitter can be precisely regulated by the positions and widths of the sub-waveguides.

关键词： femtosecond laser direct writing beam splitter lithium niobate crystal.

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HSC-YOLOv7:An Enhanced YOLOv7 for Small Object Detection

HSC-YOLOv7:An Enhanced YOLOv7 for Small Object Detection

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第43届中国控制会议

作者： Yuhang liu Huibo Zhou hongliang liu Ming Zhao School of Mathematical Sciences Harbin Normal University

Detection of small-scale objects is an emerging research area with substantial potential for growth and significant practical relevance in the domain of object *** issue of false detections in small object detection persists as a complex research *** tackle the accuracy issues inherent in small object detection,an enhanced YOLOv7 object detection model is *** proposed improvements include:Firstly,the model incorporates a specialized section for detecting small targets to augment the network's capability in identifying small ***,it introduces an enhanced SPD-CBAM(SC) network backbone,which integrates SPD-Conv and CBAM attention mechanisms into the original *** integration aims to boost the recognition ability of effective features for small targets while mitigating the impact of ***,it utilizes SIoU to replace the loss function in the conventional model for optimization,thereby enhancing the network's *** comparisons were conducted on the publicly available VisDrone-2019 dataset,revealing that the enhanced network model exhibited improvements over the original network in both mAP@[.5:.95] and mAP@.5 for the selected dataset *** enhanced model demonstrated superior performance,making it more suitable for the complex small object detection scenarios proposed in the present study.

关键词： YOLOv7 Drone Images Small Object Detection

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