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Three-stage niobium mineralization at Bayan Obo, China

National Science Review 2024年第4期11卷 102-110页

作者： yan Yu yang Li Yu Liu Xiao-Xiao ling Li-Guang Wu Li yang Lan yang Bo yang Yong-Gang zhao Xian-Hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

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A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： zhao Yiyang LIU Xun CAO JiaBin LIU JinYu XU yan yan WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

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Effects and mechanisms of Helicobacter pylori infection on the occurrence of extra-gastric tumors

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World Journal of Gastroenterology 2024年第37期30卷 4090-4103页

作者： Shi-Qing zhao Hui-ling Zheng Xiao-Tian Zhong Zi-Ye Wang Yi Su yan-yan Shi Research Center of Clinical Epidemiology Peking University Third HospitalBeijing 100191China Health Science Center Peking UniversityBeijing 100191China Department of Gastroenterology Peking University Third HospitalBeijing 100191China

Helicobacter pylori(***)colonizes the human stomach and many studies have discussed the mechanisms of *** infection leading to gastric diseases,including gastric ***,increasing data have shown that the infection of *** may contribute to the development of extra-gastric diseases and ***,systemic immune responses,microbiome disorders,and hypergastrinemia caused by *** infection are associated with many extra-gastric *** review highlights recent discoveries;discusses the relationship between *** and various extra-gastric tumors,such as colorectal cancer,lung cancer,cholangiocarcinoma,and gallbladder carcinoma;and explores the mechanisms of extra-gastric carcinogenesis by ***,these findings refine our understanding of the pathogenic processes of ***,provide guidance for the clinical treatment and management of ***-related extra-gastric tumors,and help improve prognosis.

关键词： Helicobacter pylori Extra-gastric tumors Immune system response Mucosal barrier Gut microbiome

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Single-atom catalysts: controlled synthesis and dynamic mechanism in electrochemical oxygen evolution substitution reactions

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Rare Metals 2024年第10期43卷 4903-4920页

作者： Qin zhao Rong Gan Yi-ling Ran Quan-Lei Ma Wen-Wen Chen Yue-Xin Guo yan Zhang Ding-Sheng Wang School of Chemistry Southwest Jiaotong University School of Life Science and Engineering Southwest Jiaotong University Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua University

Single-atom catalysts(SACs) have attracted much attention in the field of electrocatalysis due to their100% atomic utilization efficiency, clear active center and adjustable support. The application of SACs to anodic oxygen evolution substitution reactions with high conversion efficiency and selectivity is undoubtedly ***, a full understanding of the interactions between metal single-atom active sites and supports, and an in-depth understanding of the active centers and catalytic mechanisms of SACs in the electro-oxidation of small molecules are the keys to the development of high-performance catalysts. This review focuses on the synthesis of different support SACs and the interactions between single atoms and supports at the inter-face, and introduces the reaction mechanism of SACs in the electro-oxidation of different small-molecule substrates, such as ethanol, urea and hydrazine, with the aim of providing insights and ideas for the design of more efficient and ideal catalysts. Finally, we discuss the current challenges and future opportunities in the field.

关键词： Synthesis (chemical)

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Impact of coal resource development on eco-environment and its restoration in west of China

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中国有色金属学会会刊：英文版 2005年第S1期15卷 176-179页

作者： HU Zhen-qi, zhao yan-ling, GAO Yong-guang (China University of Mining and Technology(Beijing Campus), Beijing 100083, China) China Univ Min & Technol Beijing 100083 Peoples R China

West China has rich mineral resources, especially in coal resources with very good mining conditions. Coal resource development is the one of important tasks in the Chinese “West Development”. Thus, the impact of coal resources development on eco-environment and its restoration is worth studying. This study shows that there are many environmental problems such as land damage, coal wastes, damage of hydro-geological condition and pollution of water resource, airborne effluents (industrial exhausts and methane emission from underground), dust, waste, water. Land damage and land desertification are the most important environmental issue in west China. Therefore, the stress of environmental restoration should be desert presentation and disturbed-land reclamation. To control environmental damages and rehabilitate the eco-environment, environmental restoration techniques are also discussed.

关键词： coal mining eco-environment ecological restoration

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Radar false alarm plots elimination based on multi-feature extraction and classification

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 83-92页

作者： Cheng Yi zhao yan Yin Peiwen School of Control Science and Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Intelligent Control of Electrical Equipment Tianjin 300387China

Caused by the environment clutter,the radar false alarm plots are *** false alarm points has always been a key issue in Radar plots *** this paper,a radar false alarm plots elimination method based on multi-feature extraction and classification is proposed to effectively eliminate false alarm ***,the density based spatial clustering of applications with noise(DBSCAN)algorithm is used to cluster the radar echo data processed by constant false-alarm rate(CFAR).The multi-features including the scale features,time domain features and transform domain features are ***,a feature evaluation method combining pearson correlation coefficient(PCC)and entropy weight method(EWM)is proposed to evaluate interrelation among features,effective feature combination sets are selected as inputs of the ***,False alarm plots classified as clutters are *** experimental results show that proposed method can eliminate about 90%false alarm plots with less target loss rate.

关键词： radar plots elimination density based spatial clustering of applications with noise multi-feature extraction classifier

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Global trend of nondrug and nonsedativehypnotic treatment forinsomnia: a bibliometric study

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Journal of Traditional Chinese Medicine 2024年第3期44卷 595-608页

作者： LEI Hanzhou XU Guixing WEI Zepeng zhao ling LIANG Fanrong Acupuncture and Tuina School Chengdu University of Traditional Chinese MedicineChengdu 610075China Department of Haematology Royal North Shore HospitalSydney2065Australia

OBJECTIVE: To present a bibliometric analysis of global scientific publications on the nondrug and nonsedative hypnotic treatment of insomnia with regard to influential institutions, publications, countries, research hotspots,trends, and frontiers. METHODS: A literature review was conducted by searching the Web of Science Core Collection(Wo SCC) and China National Knowledge Infrastructure(CNKI) databases to identify all publications related to the nondrug and nonsedative hypnotic treatment of insomnia from 2000 to 2021. Eligible publications were reviewed, including annual publication increments, citation analyses, international collaborations, and keyword analyses. The data were analysed using Cite Space(vers5.8.R3, 6.1.R2 and 6.1.6, College of Computing and Informatics, Philadelphia, PA, USA) and virtualized by knowledge maps. RESULTS:In total, 9832 publications were included in this analysis. The results from the WoSCC showed that the United States of America(Count = 2268, 40.33%), Stanford University(Count = 141, 2.51%), and the United States Department of Health and Human Services were the leading country, institute, and funding agency regarding the number of publications, respectively. “Cognitive-behavioural therapy” was the most popular research topic generated from the cocited reference. The most frequently co-occurring keywords were insomnia, cognitive behavioural therapy, disorder, depression, quality of life, Meta-analysis, older adult, sleep, prevalence and efficacy, while keywords including clinical practice guideline, guideline, and Tai Chi remained popular after 2021. Circadian rhythm was the strongest research frontier for 2000-2021. In China, Chengdu University of Traditional Chinese Medicine(Count = 69, 4.79%) was the most productive institute in this field. The most frequently co-occurring keywords from Chinese literature were sleep disorder, sleep quality, acupuncture and moxibustion, Parkinson's disease, transcranial magnetic stimulation, health

关键词： hypnotics and sedatives cognitive behavioral therapy complementary therapies bibliometrics CiteSpace visualization analysis scientometrics

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Use of Network Pharmacology and Molecular Docking to Investigate the Mechanism by Which Ginseng Ameliorates Hypoxia

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Biomedical and Environmental Sciences 2018年第11期31卷 855-858页

作者： WANG Tao LI Hao Tian WEI Shi Zhang CAI Hua Dan ZHU Yun LIU Hong Hong LI Yong Zhi WANG Jia Ping ZOU Wen Jun zhao yan ling College of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 610075China Department of Pharmacy 302Military'Hospital of ChinaBeijing 100039China China Astronaut Research and Training Centre Beijing 100094China Integrative Medical Center 302Military Hospital of ChinaBeijing 100039China

Hypoxia is a common pathological process in various clinical diseases and is characterized by abnormal changes in metabolism, function, and morphological structure of tissues resulting from insufficient oxygen supply or oxygen barriers in tissues. In particular, hypoxia in vital organs such as the brain and heart is an important cause of death;. The prevention of tissue hypoxia and the

关键词： In Use of Network Pharmacology and Molecular Docking to Investigate the Mechanism by Which Ginseng Ameliorates Hypoxia Figure

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Investigating effect of coke porosity on blast furnace performance based on multi-physical fields

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Journal of Iron and Steel Research International 2024年第2期31卷 357-367页

作者： Ji Chen zhao Lei Zhe Yao Li Wang Qiang ling Ping Cui Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan243002AnhuiChina Shanxi Academy of Printing Technology Research Institute Co. Ltd.Xi’an710077ShaanxiChina

Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)***,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions *** makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic ***,the proposed model was validated with the production *** coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were *** results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,***,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive *** the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.

关键词： Blast furnace Mathematical model Multi-physical field Simulation Coke porosity

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Performance improvements in complementary metal oxide semiconductor devices and circuits based on fin field-effect transistors using 3-nm ferroelectric Hf_(0.5)Zr_(0.5)O_(2)

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Rare Metals 2024年第7期43卷 3242-3249页

作者： zhao-Hao Zhang yan-Na Luo Gao-Bo Xu Jia-Xin Yao Zhen-Hua Wu Hong-Bin zhao Qing-Zhu Zhang Hua-Xiang Yin Jun Luo Wen-Wu Wang Hai-ling Tu Integrated Circuit Advanced R&D Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China

In this work,a conventional HfO_(2) gate dielectric layer is replaced with a 3-nm ferroelectric(Fe) HZO layer in the gate stacks of advanced fin field-effect transistors(FinFETs).Fe-induced characteristics,e.g.,negative drain induced barrier lowering(N-DIBL) and negative differential resistance(NDR),are clearly observed for both p-and n-type HZO-based *** characteristics are attributed to the enhanced ferroelectricity of the 3-nm hafnium zirconium oxide(HZO) film,caused by Al doping from the TiAlC capping *** mechanism is verified for capacitors with structures similar to the *** to the enhanced ferroelectricity and N-DIBL phenomenon,the drain current(I_(DS))of the HZO-FinFETs is greater than that of HfO_(2)-FinFETs and obtained at a lower operating ***,circuits based on HZO-FinFET achieve higher performance than those based on HfO_(2)-FinFET at a low voltage drain(V_(DD)),which indicates the application feasibility of the HZO-FinFETs in the ultralow power integrated circuits.

关键词： FinFET Ferroelectric Hafnium zirconium oxide Subthreshold swing Low power

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