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Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

Journal of Iron and Steel Research(International) 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui Chen Hui li kai-hua Shi Hui-wen Xiong Xin Xiang li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

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A Calculation Method of Double Strength Reduction for Layered Slope Based on the Reduction of Water Content Intensity

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工程与科学中的计算机建模(英文) 2024年第1期138卷 221-243页

作者： Feng Shen Yang Zhao Bingyi li kai Wu School of Civil Engineering Suzhou University of Science and TechnologySuzhou215011China R&D Department Suzhou Jcon Greenbuild Fabricated Co.Ltd.Suzhou215004China

The calculation of the factor of safety(FOS)is an important means of slope *** paper proposed an improved double strength reductionmethod(DRM)to analyze the safety of layered *** physical properties of different soil layers of the slopes are different,so the single coefficient strength reduction method(SRM)is not enough to reflect the actual critical state of the *** that the water content of the soil in the natural state is the main factor for the strength of the soil,the attenuation law of shear strength of clayey soil changing with water content is *** paper also establishes the functional relationship between different reduction ***,a USDFLD subroutine is programmed using the secondary development function of finite element *** the relationship between field variables and calculation time realizes double strength reduction applicable to the layered ***,by comparing the calculation results of different examples,it is proved that the stress and displacement distribution of the critical slope state obtained by the improved method is more realistic,and the calculated safety factor is more *** newly proposedmethod considers the difference of intensity attenuation between different soil layers under natural conditions and avoids the disadvantage of the strength reduction method with uniform parameters,which provides a new idea and method for stability analysis of layered and complex slopes.

关键词： Double strength reduction slopes stability water content factor of safety numerical methods

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Double plasma molecular adsorption system for Stevens–Johnson syndrome/toxic epidermal necrolysis:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1371-1377页

作者： You-Wen Tan li-Ping liu kai Zhang Department of Hepatology The Third Hospital of Zhenjiang Affiliated Jiangsu UniversityZhenjiang 212003Jiangsu ProvinceChina

BACKGROUND Stevens–Johnson syndrome and toxic epidermal necrolysis(SJS/TEN)are very serious skin allergies,with an etiology related to infections and *** the coronavirus disease 2019(COVID-19)pandemic,severe acute respiratory syndrome coronavirus-2 has also been considered to cause SJS/*** SUMMARY We report the case of a woman in her thirties who took acetaminophen after contracting *** 3 d of fever relief,she experienced high fever and presented with SJS/TEN symptoms,accompanied by intrahepatic *** days of corticosteroid treatment did not alleviate the skin damage;therefore,double plasma molecular adsorption system(DPMAS)therapy was initiated,with treatment intervals of 48 *** skin symptoms improved gradually and were resolved after seven DPMAS *** DPMAS therapy is beneficial for abrogating SJS/TEN because plasma adsorption and perfusion techniques reduce the inflammatory mediators(e.g.,tumor necrosis factor-alpha and interleukin-10 and-12)speculated to be involved in the pathology of the skin conditions.

关键词： Stevens-Johnson Toxic epidermal necrolysis COVID-19 Double plasma molecular adsorption system SARS-CoV-2 Case report

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Transglutaminase 2 serves as a pathogenic hub gene of KRAS mutant colon cancer based on integrated analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2074-2090页

作者： Wei-Bin Peng Yu-Ping li Yong Zeng kai Chen First People’s Hospital of Foshan Foshan 528000Guangdong ProvinceChina Department of Radiation Oncology Cancer Hospital of Shantou University Medical CollegeShantou 515031Guangdong ProvinceChina

BACKGROUND Colon cancer is acknowledged as one of the most common malignancies worldwide,ranking third in United States regarding incidence and ***,approximately 40%of colon cancer cases harbor oncogenic KRAS mutations,resulting in the continuous activation of epidermal growth factor receptor *** To investigate the key pathogenic genes in KRAS mutant colon cancer holds considerable *** Weighted gene co-expression network analysis,in combination with additional bioinformatics analysis,were conducted to screen the key factors driving the progression of KRAS mutant colon ***,various in vitro experiments were also conducted to explore the biological function of transglutaminase 2(TGM2).RESULTS Integrated analysis demonstrated that TGM2 acted as an independent prognostic factor for progression-free *** analysis on tissue microarrays revealed that TGM2 was associated with an elevated probability of perineural invasion in patients with KRAS mutant colon ***,biological roles of the key gene TGM2 was also assessed,suggesting that the downregulation of TGM2 attenuated the proliferation,invasion,and migration of the KRAS mutant colon cancer cell *** This study underscores the potential significance of TGM2 in the progression of KRAS mutant colon *** insight not only offers a theoretical foundation for therapeutic approaches but also highlights the need for additional clinical trials and fundamental research to support our preliminary findings.

关键词： Colon cancer KRAS mutation Transglutaminase 2 Weighted gene co-expression network analysis

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Artificial stepwise light harvesting system in water constructed by quadruple hydrogen bonding supramolecular polymeric nanoparticles

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Chinese Chemical Letters 2024年第2期35卷 370-373页

作者： Tangxin Xiao Xiuxiu li liangliang Zhang kai Diao Zheng-Yi li Xiao-Qiang Sun Leyong Wang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Stepwise energy transfer is ubiquitous in natural photosynthesis,which greatly promotes the widespread use of solar ***,we constructed a supramolecular light harvesting system based on sequential energy transfer through the hierarchical self-assembly of M,which contains a cyanostilbene core flanked by two ureidopyrimidinone motifs,endowing itself with both aggregation-induced emission behavior and quadruple hydrogen bonding *** monomer M can self-assemble into hydrogen bonded polymers and then form supramolecular polymeric nanoparticles in water through a mini-emulsion *** nanoparticles were further utilized to encapsulate the relay acceptor ESY and the final acceptor NDI to form a two-step FRET *** fluorescence including a white-light emission was successfully *** work not only shows a desirable way for the fabrication of efficient two-step light harvesting systems,but also shows great potential in tunable photoluminescent nanomaterials.

关键词： light harvesting system Supramolecular polymer Quadruple hydrogen bonding AIE Self-assembly

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Increasing the toughness while reducing the viscosity of carbon nanotube/ polyether imide/polyether ether ketone nanocomposites

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新型炭材料（中英文） 2024年第4期39卷 715-728页

作者： SONG Jiu-peng ZHAO Yan li Xue-kuan XIONG Shu li Shuang WANG kai School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Polyether ether ketone(PEEK)has good mechanical ***,its high viscosity when molten limits its use because it is hard to *** nanocomposites containing both carbon nanotubes(CNTs)and polyether imide(PEI)were pre-pared by a direct wet powder blending method using a vertical injection molding *** addition of an optimum amount of PEI lowered the viscosity of the molten PEEK by approximately 50%while producing an increase in the toughness of the nanocom-posites,whose strain to failure increased by 129%,and fracture energy increased by 97%.The uniformly dispersed CNT/PEI powder reduced the processing difficulty of PEEK nanocomposites without affecting the thermal *** improvement of the strength and viscosity of PEEK facilitate its use in the preparation of thermoplastic composites.

关键词： Nanocomposites Mechanical properties Rheological properties Microstructural analysis

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Novel method for the recognition of Jinnan cattle action using bottleneck attention enhanced two-stream neural network

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 203-210页

作者： Wangli Hao Meng Han kai Zhang li Zhang Wangbao Hao Fuzhong li Zhenyu liu School of Software Shanxi Agricultural UniversityJinzhong 030801ShanxiChina Yuncheng National Jinnan Cattle Genetic Resources and Gene Protection Center Yongji 044500ShanxiChina Yongji Puzhou Old City Beimenwai Cattle Farm Yongji 044500ShanxiChina College of Engineering Shanxi Agricultural UniversityJinzhong 030801ShanxiChina

Effective and accurate action recognition is essential to the intelligent breeding of the Jinnan ***,there are still several challenges in the current Jinnan cattle action *** methods are based on manual characteristics and low recognition *** study is aimed at the efficient and accurate development of Jinnan cattle action recognition methods to overcome existing problems and support intelligent *** acquired data from the previous methods contain a lot of noise,which will cause individual cattle to have excessive behaviors due to *** the high labor costs,low efficiency,and low model accuracy of the above approaches,this study developed a bottleneck attention-enhanced two-stream(BATS)Jinnan cattle action recognition *** primarily comprises a Spatial Stream Subnetwork,a Temporal Stream Subnetwork,and a Bottleneck Attention *** can capture the spatial-channel dependencies in RGB and optical flow two branches respectively,so as to extract richer and more robust ***,the decision of the two branches can be fused to gain improved cattle action recognition *** with the traditional methods,the model proposed in this study has achieved state-of-the-art recognition performance,and the accuracy of motion recognition was 96.53%,which was 4.60%higher than other *** method significantly improves the efficiency and accuracy of behavior recognition and provides an important research foundation and direction for the development of higher-level behavior analysis models in the future development of smart animal husbandry.

关键词： Jinnan cattle action recognition bottleneck attention two-stream neural network

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Automatic velocity picking based on optimal key points tracking algorithm

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Petroleum Science 2024年第2期21卷 903-917页

作者： Yong-Hao Wang Wen-kai Lu Song-Bai Jin Yang li Yu-Xuan li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

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Tourmaline geochemistry as genetic evolution and metallogenic potential indicators of pegmatites: a case study from the Tugeman Be-li deposit， Middle Altun

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Journal of Earth Science 2024年

作者： Hang li Xingwang Xu Tao Hong Qiang Ke Yince Ma kai Kang Zhiquan Yang Changsheng Guo College of Architecture and Civil Engineering Sanming University Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences Innovation Academy for Earth Science Chinese Academy of Sciences Guangdong Provincial Key Lab of Geodynamics and Geohazards School of Earth Sciences and Engineering Sun Yat-Sen University Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) No.3 Geological Party Xinjiang Bureau of Geology and Mineral Exploration and Development

Tourmaline is a common borosilicate mineral in granite and pegmatite， and it is also an important carrier to record the physicochemical evolution information of magmas. However， the genetic relationship between pegmatite-type rare metal mineralization potential and tourmaline-bearing pegmatites is not clear， and the tourmaline geochemical indication of the mineralization type of rare metals needs to be supplemented. In the middle Altun region， extensive tourmaline-bearing pegmatite dykes are prevalent within and surrounding the Tugeman complex. In this paper， the petrology and geochemical characteristics of tourmaline within the pegmatite of the Tugeman Be-li deposit have been comprehensively analyzed. The research delves into the genetic evolution and metallogenic potential of the pegmatite， emphasizing the indicative role of tourmaline geochemistry in discerning mineralization types in the Tugeman Be-li deposit. Major and trace element analysis of tourmaline reveals varying contents of FeO （9.37 wt.%–17.10 wt.%）， Al2O3（28.64 wt.%–35.22% wt.%）， and MgO （0.13 wt.%–2.47 wt.%） in the Tugeman Be–li pegmatite. li， Zn， and Sn contents range from 204 ppm to 1 590 ppm， 1 143 ppm to 4 089 ppm， and 74 ppm to 396 ppm， respectively. The tourmaline analyzed in this study is magmatic origin and belongs to schorl series， exhibits substitution relationships， including (Na， Fe2+)(X□， Al)-1， (Fe2+， Fe3+)（Mg， Al）-1， (Al，X□)(R2+， Na)-1，（Na， Mg）(X□， Al)-1andX□NaR2+-1. The trace element data of tourmaline show that lithium has four enrichment stages in different mineral crystallization phases. Notably， the tendency of tourmaline in the Tugeman Be-li pegmatite to evolve towards elbaite implies a magmatic evolution sequence from low to high， transitioning through microcline-albite pegmatite， muscovite-microcline-albite pegmatite， albite pegmatite， and microcline pegmatite. Furthermore， we also propose that the Sc content in schorl can serve as an indicator of pegmatite mineralization typ

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Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： Xuan-Hong Cai Zhen-Hua Wang ben Niu Jin-Feng li Qing Wang Show authors Key Laboratory of Materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy

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