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Rare Metals 2024年第5期43卷 2275-2281页

作者： guo-chao li Xu Cheng Hua-Ming Wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy Laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property

Effects of residual plastic film on crop yield and soil fertility in a dryland farming system

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Journal of Integrative Agriculture 2023年第12期22卷 3783-3791页

作者： WANG Dong XI Yue SHI Xiao-yan guo chao-li ZHONG Yu-jie SONG chao GUAN Yu HUANG Lu YANG Qi-feng li Feng-min College of Ecology Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Agriculture Nanjing Agricultural UniversityNanjing 210095P.R.China State Key Laboratory of Grassland Agro-Ecosystems Institute of Arid Agroecology/College of EcologyLanzhou UniversityLanzhou 730000P.R.China Teaching Affairs Office Jilin Normal UniversitySiping 136099P.R.China Department of Resources and Environmental Science College of Agriculture/The Key Laboratory of Oasis Eco-Agriculture of the Xinjiang Production and Construction CorpsShihezi UniversityShihezi 832000P.R.China Institute of Microbiology Chinese Academy of SciencesBeijing 100101P.R.China Gansu Provincial Department of Agriculture and Rural Affairs Lanzhou 730000P.R.China

Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid ***,the presence of residual film in farmland soil has also drawn much *** this study,three experiments were *** first two experimental designs included 0,450,1350,and 2700 kg ha^(-1) of residual film pieces of approximately 5 cm side length added to field soil(0-20 cm soil depth)for seven years and added to pots for four *** the third experiment,1350 kg ha^(-1)of the residual film with different side lengths(2-5,5-10,10-15,and 15-20 cm)was added to field soil for six years to explore the effect of residual film fragment size on soil nutrients,soil microorganisms,crop growth and *** residual film had little effect on the soil moisture at a field depth of 0-2(or 0-1.8)*** were no significant effects on organic carbon,total nitrogen,inorganic nitrogen,total phosphorus or available phosphorus in the 0-20 cm soil *** presence of residual film decreased the richness and diversity of the bacterial community of the surface soil of the residual film,but it had no significant effect on the microbial community of the non-surface *** emergence rates of wheat and lentils occasionally decreased significantly with different amounts of residue fragments added to the *** 450-2700 kg ha^(-1),the residual film reduced the plant height and stem diameter of maize and significantly reduced the shoot biomass of harvested maize by 11-19%.The average yields of maize and potato over the seven years decreased,but there were almost no significant statistical differences among the *** results provide important data for a comprehensive scientific understanding of the effects of residual film on soil and crops in dryland farming systems.

关键词： residual film soil nutrients microbial community crop yield

Freestanding MoSe_(2)nanoflowers for superior li/Na storage properties

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Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu chao-Qun Shang guo-Fu Zhou Xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible li/Na storage applications.

关键词： li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

Side Information-Based Stealthy False Data Injection Attacks Against Multi-Sensor Remote Estimation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1054-1056页

作者： Haibin guo Zhong-Hua Pang chao li the Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of TechnologyBeijing 100144China

Dear Editor,This letter investigates a novel stealthy false data injection(FDI)attack scheme based on side information to deteriorate the multi-sensor estimation performance of cyber-physical systems(CPSs).Compared with most existing works depending on the full system knowledge,this attack scheme is only related to attackers'sensor and physical process *** design principle of the attack signal is derived to diverge the system estimation ***,it is proven that the proposed attack scheme can successfully bypass the residual-based ***,all theoretical results are verified by numerical simulation.

关键词： estimation scheme system

Spontaneous acute epidural hematoma secondary to skull and dural metastasis of hepatocellular carcinoma: A case report

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World Journal of Clinical Cases 2022年第24期10卷 8728-8734页

作者： Guang-Zhao Lv guo-chao li Wei-Tai Tang Dong Zhou Yong Yang Department of Neurosurgery Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080Guangdong ProvinceChina Department of Neurosurgery Luoding People’s HospitalYunfu 527200Guangdong ProvinceChina

BACKGROUND The skull and dura are uncommon sites for the metastasis of hepatocellular carcinoma(HCC).Spontaneous acute epidural hematoma(AEDH)is also very *** report here a spontaneous AEDH secondary to skull and dural metastasis of *** case is extremely *** SUMMARY A 48-year-old male patient with a history of HCC developed unconsciousness *** computed tomography showed"a huge AEDH in the left parietal and occipital region with osteolytic destruction of the left parietal *** operation was performed to evacuate the hematoma and resect the *** study revealed that the lesion was the metastases from *** patient died of lung infection,anemia,and liver failure 3 wk after *** Spontaneous AEDH caused by hepatocellular carcinoma(HCC)dural and skull metastases is extremely rare,the outcome is ***,early diagnosis is *** the level of AFP does not decrease with the shrinkage of intrahepatic lesions after treatment,it is necessary to be alert to the existence of extrahepatic *** most of the patients had scalp and bone masses,physicians should pay attention to the patient's head *** a patient with the history of HCC had sudden neurological dysfunction,the possibility of spontaneous AEDH caused by the skull and dura mater metastases should be *** hemorrhage is common in the skull HCC metastases,for patients with spontaneous AEDH accompanied by skull osteolytic lesions,it is also necessary to be alert to the possibility of *** AEDH secondary to HCC metastases,early diagnosis and timely treatment are critical to improve the patients’outcomes.

关键词： Spontaneous acute epidural hematoma Hepatocellular carcinoma Skull and dural metastasis Case report

CVTD: A Robust Car-Mounted Video Text Detector

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Computers, Materials & Continua 2024年第2期78卷 1821-1842页

作者： Di Zhou Jianxun Zhang chao li Yifan guo Bowen li Department of Computer Science and Engineering Chongqing University of TechnologyChongqingChina College of Information and Engineering Jingdezhen Ceramic UniversityJingdezhenChina

Text perception is crucial for understanding the semantics of outdoor scenes,making it a key requirement for building intelligent systems for driver assistance or autonomous *** information in car-mounted videos can assist drivers in making ***,Car-mounted video text images pose challenges such as complex backgrounds,small fonts,and the need for real-time *** proposed a robust Car-mounted Video Text Detector(CVTD).It is a lightweight text detection model based on ResNet18 for feature extraction,capable of detecting text in arbitrary *** model efficiently extracted global text positions through the Coordinate Attention Threshold Activation(CATA)and enhanced the representation capability through stacking two Feature Pyramid Enhancement Fusion Modules(FPEFM),strengthening feature representation,and integrating text local features and global position information,reinforcing the representation capability of the CVTD *** enhanced feature maps,when acted upon by Text Activation Maps(TAM),effectively distinguished text foreground from non-text ***,we collected and annotated a dataset containing 2200 images of Car-mounted Video Text(CVT)under various road conditions for training and evaluating our model’s *** further tested our model on four other challenging public natural scene text detection benchmark datasets,demonstrating its strong generalization ability and real-time detection *** model holds potential for practical applications in real-world scenarios.

关键词： Deep learning text detection Car-mounted video text detector intelligent driving assistance arbitrary shape text detector

Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG Zhen FU Yong li chao CAI Xi guo Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

Standardized Volume Power Density Boost in Frequency-Up Converted Contact-Separation Mode Triboelectric Nanogenerators

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Research 2024年第2期2023卷 691-702页

作者： Zhongjie li chao Yang Qin Zhang Geng Chen Jingyuan Xu Yan Peng Hengyu guo School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444P.R.China Institute of Artificial Intelligence Shanghai UniversityShanghai 200444P.R.China National Engineering Research Center of Turbo-Generator Vibration School of Energy and EnvironmentSoutheast UniversityNanjing 210096P.R.China institute of Microstructure Technology Karlsruhe Institute of TechnologyKarlsruhe 76344Germany Shanghai Artificial Intelligence Laboratory Shanghai 200444P.R.China Department of Applied Physics Chongqing UniversityChongqing 400044P.R.China

The influence of a mechanical structure's volume increment on the volume power density (VPD) of triboelectric nanogenerators (TENGs) is often neglected when considering surface charge density and surface power density. This paper aims to address this gap by introducing a standardized VPD metric for a more comprehensive evaluation of TENG performance. The study specifically focuses on 2 frequency-up mechanisms, namely, the integration of planetary gears (PG-TENG) and the implementation of a double-cantilever structure (DC-TENG), to investigate their impact on VPD. The study reveals that the PG-TENG achieves the highest volume average power density, measuring at 0.92 W/m^(3). This value surpasses the DC-TENG by 1.26 times and the counterpart TENG by a magnitude of 69.9 times. Additionally, the PG-TENG demonstrates superior average power output. These findings introduce a new approach for enhancing TENGs by incorporating frequency-up mechanisms, and highlight the importance of VPD as a key performance metric for evaluating TENGs.

关键词： increment neglected considering

Structural Evolution of Ultra-High Molecular Weight Polyethylene Low-Entangled Films with Reserved Shish Crystals During Hot Stretching

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CHINESE JOURNAL OF POLYMER SCIENCE 2024年第8期42卷 1227-1242页

作者： Gao, Jia-Wei Chen, li Zhong, Ye-Shun Xing, chao-Wei li, Yi-guo Wang, Zong-Bao Ningbo Univ Sch Mat Sci & Chem Engn Ningbo 315211 Peoples R China

Shish crystals are crucial to achieving high performance low-dimensional ultra-high molecular weight polyethylene (UHMWPE) products. Typically, high stretch and shear flow fields are necessary for the formation of shish crystals. In this study, UHMWPE gel films with reserved shish crystals were prepared by gel molding, the structural evolution and properties of UHMWPE films stretched at temperatures of 100, 110, 120 and 130 degrees C were investigated by in situ small-angle X-ray scattering (SAXS)/ultra-small-angle X-ray scattering (USAXS)/wide-angle X-ray diffraction (WAXD) measurements as well as scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) measurements. Our findings showed that the reserved shish crystals can facilitate the formation and structural evolution of shish-kebab crystals during the hot stretching. Additionally, the reserved shish crystals promote the structural evolution of UHMWPE films to a greater extent when stretched at 120 and 130 degrees C, compared to 100 and 110 degrees C, resulting in higher crystallinity, orientation, thermal properties, breaking strength and Young's modulus. Compared to UHMWPE high-entangled films with reserved shish crystals prepared by compression molding, UHMWPE low-entangled films with reserved shish crystals prepared by gel molding are more effective in inducing the formation and evolution of shish-kebab crystals during the hot stretching, resulting in increased breaking strength and Young's modulus.

关键词： UHMWPE low-entangled films Reserved shish crystals Structural evolution Hot stretching SMALL-ANGLE SCATTERING MECHANICAL-PROPERTIES INDUCED CRYSTALliZATION FIBRILLAR CRYSTALS NANOCRYSTAL FIBERS UHMWPE FIBERS KEBAB MORPHOLOGY DEFORMATION POLYMERIZATION

Effects of annealing temperature and cooling rate on microstructures of a novel titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si manufactured by laser additive manufacturing

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Journal of Iron and Steel Research(International) 2018年第4期25卷 442-452页

作者： guo-chao li Xu Cheng Xiang-jun Tian National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and Engineering Beihang University Beijing 100091 China

The microstructure changes of Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si alloy manufactured by laser additive manufacturing （LAM） are systematically investigated with statistical analysis of primary α phase （αp） and secondary α phase （αs） under different annealing conditions. Results indicate that, with the increase in holding temperature, the content of αp lamellas decreases with the increasing αs content, maintaining the total α phases concentration stabilized. The width of αp lamellas and the nominal specific surface area of α phase both exhibit positive correlation with the temperature, while the increment of αp and the widths of αs lamellas show an increase-decrease tendency. Besides, with the decrease in cooling rate, the total content of α and the width of αp lamellas increase, while the nominal specific surface area of α phase shows no significant change. The results indicate that, in the annealing process, the holding temperature determines the surplus and growth interfaces of % lamellas, and the cooling rate influences the nucleation quantity of c^s in unit time. During the cooling stage, the αp lamellas grow initially, and then, the nucleation and crab-like structure growth occur followed by those of the αs lamellas. The time intervals among them are influenced by cooling rate. The mechanism of microstructure formation of the LAMed titanium alloy during annealing stage was discussed, which would guide for the heat treatment method to achieve required microstructure.

关键词： Novel titanium alloy Annealing Microstructure statistics Holding temperature Cooling rate