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High-current pulsed electron beam modification on microstructure and performance of Cu/CuW diffusion bonding joints

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rare metals 2024年第6期43卷 2819-2831页

作者： na-na Tian Cong-Lin Zhang Peng Lyu Jin-Tong Guan Jie Cai Qing-Feng Guan Shun Guo School of materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of material Science and Engineering Yancheng Institute of TechnologyYancheng 221051China Engineering Institute of Advanced manufacturing and modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

This study investigates the influence of high-current pulsed electron beam(HCPEB)modification on the microstructure and shear strength of Cu/CuW *** solid-state diffusion bonding of modified-Cu(mCu)and modified-CuW(m-CuW)was achieved by HCPEB modification pretreatment at a temperature of 800-900℃and a pressure of 5 mPa for 10-50 *** demonstrate that HCPEB modification facilitates the dissolution of W and Cu,resulting in the formation of a Cu_(0.4)W_(0.6)solid solution and thus enhancing the uniform distribution of ***,HCPEB-induced defects play a beneficial role in promoting the diffusion process by providing fast diffusion paths for *** optimal joints with the maximum shear strength of 213.7 mPa were obtained through bonding m-Cu and m-CuW at 900℃and 5 mPa for 30 min,which attributes to the combined effects of fine-grained strengthening and solid solution ***,the application of HCPEB modification showcases its effectiveness in promoting element diffusion and enhancing the mechanical performance of the joints.

关键词： HCPEB Element diffusion Shear strength Crystal defects Surface modification

Effect of La on the Corrosion Behavior and mechanism of 3Ni Weathering Steel in a Simulated marine Atmospheric Environment

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Acta metallurgica Sinica(English Letters) 2024年第2期37卷 308-324页

作者： Gang Niu rui Yuan r.D.K.misra na Gong Zhi-Hui Zhang Hao-Xiu Chen Hui-Bin Wu Cheng-Jia Shang Xin-Ping mao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Laboratory for Excellence in Advanced Steel research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX79968USA Institute of materials research and Engineering Agency for ScienceTechnologyand ResearchSingapore138634Singapore Department of materials Science and Engineering University of TorontoTorontoONM5S 3E4Canada

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La,as determined through electrochemical analysis and rust layer *** results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment,thereby reducing the corrosion rate and improving the protection of the rust *** influence of La on corrosion resistance can be attributed to two primary ***,La functions as a grain refiner,minimizing the potential difference of the micro-regions on the substrate surface,thereby significantly reducing the corrosion of bare steel in the marine ***,La inhibits the process of Fe_(3)O_(4) oxidation back toγ-FeOOH during corrosion at the local site,thus decreasing the formation ofγ-FeOOH and enhancing the charge transfer *** research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.

关键词： Weathering steel rare earth rust layer Corrosion behavior Corrosion resistance

The Adjustment Analysis method of the Active Surface Antenna Based on Convolutional Neural Network

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research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi na Wang Qian Xu Shufei Feng School of mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical

Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2135-2144页

作者： Lu-na Bai Lu-Xian Zhang Department of radiology Zhongshan Hospital Xiamen UniversityXiamen 361004Fujian ProvinceChina

BACKGrOUND Colorectal cancer(CrC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many *** early detection and diagnosis of CrC are crucial for improving treatment success and patient survival ***,imaging techniques have been hypothesized to be essential in managing CrC,with magnetic resonance imaging(mrI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment *** To explore the effectiveness of mrI and SCT in the preoperative staging of CrC and the prognosis of laparoscopic *** Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent mrI and SCT and were diagnosed with *** precision of mrI and SCT for the presurgical classification of CrC was assessed,and pathological staging was used as a *** operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with *** Pathological biopsies confirmed the following CrC stages:23,23,32,and 17 at T1,T2,T3,and T4,*** were 39 cases at the N0 stage,22 at N1,34 at N2,44 at m0 stage,and 51 at *** pathological findings as the benchmark,the combined use of mrI and SCT for preoperative TNm staging in patients with CrC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(Preceiver operating characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volu

关键词： magnetic resonance imaging Spiral computed tomography Colorectal cancer Prognosis receiver operating characteristic curve retrospective study

Improvement of mechanical properties and investigation of strengthening mechanisms on the Ti_(3)AlC_(2) ceramic with nanosized WC addition

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Journal of Advanced Ceramics 2024年第6期13卷 861-876页

作者： Yi Zhong Ying Liu Qinkai Jiang na Jin Zifeng Lin Jinwen Ye School of materials Science&Engineering Sichuan UniversityChengdu 610065China Yibin r&D Park Yibin Industrial Technology Research InstituteSichuan UniversityYibin 644005China

Ti_(3)AlC_(2) (TAC) has great potential for use as an ablation material in aerospace applications due to its great oxidation/ablation resistance, but its high-temperature strength and thermal shock resistance still have much room for simultaneous improvement under fast temperature variation conditions. Herein, we used Ti_(3)AlC_(2) and WC powders as raw materials and successfully fabricated textured (Ti,W)_(3)AlC_(2) ceramic with small amounts of TiC and Al_(2)O_(3), and room temperature mechanical properties such as flexural strength (1146±46.9 mPa), fracture toughness (11.78±0.44 mPa·m^(1/2)), and hardness (5.81±0.11 GPa) at 5 wt% WC addition were achieved. The high-temperature strength of the ceramic was significantly improved, and better thermal shock resistance from 298 to 1173 K was simultaneously acquired together with the regulation of the elastic modulus, thermal conductivity, and thermal expansion coefficient, providing (Ti,W)_(3)AlC_(2) with more possibilities for fast-temperature variation applications. Strengthening and toughening mechanisms were proposed. Scanning transmission electron microscopy high-angle annular dark-field imaging (STEm-HADDF) showed that W randomly replaced the Ti1 and Ti2 sites of Ti_(3)AlC_(2), providing a good reference for establishing crystal models, and further density functional theory (DFT) calculations based on these models indicated a higher fracture energy of (Ti,W)_(3)AlC_(2) along different crystal planes, providing superior resistance to transgranular fracture;a lower mismatch degree of (Ti,W)_(3)AlC_(2)/Al_(2)O_(3) resulted in stronger interface bonding, resulting in greater resistance to intergranular fracture as well as more balanced stress distributions at different interfaces.

关键词： mechanical properties solid solution mAX phase transmission electron microscopy(TEm) ceramic atomic structure

Insights into sensitizing and eliciting capacity of gastric and gastrointestinal digestion products of shrimp(Penaeus vannamei)proteins in BALB/c mice

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Food Science and Human Wellness 2024年第1期13卷 339-348页

作者： Yao Liu Songyi Lin Kexin Liu Shan Wang Wang Li na Sun national Engineering research Center of Seafood School of Food Science and TechnologyDalian Polytechnic UniversityDalian 116034China Collaborative Innovation Center of Seafood Deep Processing Dalian Polytechnic UniversityDalian 116034China

Shrimp(Penaeus vannamei)proteins have been shown an allergenic potential;however,little information is available on the sensitizing and eliciting capacity of shrimp protein digestion *** this study,a BALB/c mice model was used to explore the allergenicity of shrimp protein sample(SPS)and their gastric and gastrointestinal digestion products(GDS/GIDS).As compared with the SPS groups,the GDS/GIDS groups caused lower specific immunoglobulins(Ig E/Ig G1)levels(Pr than the control groups,indicating that the digestion products sensitized the ***,spleen index,mouse mast cell protease-1(m mCP-1)concentration and proportion of degranulated mast cells were significantly reduced in the GDS/GIDS groups(Pmultaneously,allergic symptoms,vascular permeability and histopathological changes of tissues were ***,the allergenicity of digestion products cannot be eliminated and still cause systemic allergic reactions in *** study showed that the digestion products of shrimp still had high sensitizing and eliciting capacity.

关键词： Penaeus vannamei Allergenicity Digestion BALB/c mice model

Neutrophil peptide 1 accelerates the clearance of degenerative axons during Wallerian degeneration by activating macrophages after peripheral nerve crush injury

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Neural regeneration research 2024年第8期19卷 1822-1827页

作者： Yuhui Kou Yusong Yuan Qicheng Li Wenyong Xie Hailin Xu na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina national Center for Trauma medicine BeijingChina Key Laboratory of Trauma and Neural regeneration(Peking University) Ministry of EducationBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina Department of Central Laboratory and Institute of Clinical molecular Biology Peking University People’s HospitalBeijingChina

macrophages play an important role in peripheral nerve regeneration,but the specific mechanism of regeneration is still *** preliminary findings indicated that neutrophil peptide 1 is an innate immune peptide closely involved in peripheral nerve ***,the mechanism by which neutrophil peptide 1 enhances nerve regeneration remains *** study was designed to investigate the relationship between neutrophil peptide 1 and macrophages in vivo and in vitro in peripheral nerve crush *** functions of rAW 264.7 cells we re elucidated by Cell Counting Kit-8 assay,flow cytometry,migration assays,phagocytosis assays,immunohistochemistry and enzyme-linked immunosorbent *** debris phagocytosis was observed using the CUBIC(Clear,Unobstructed brain/Body Imaging Cocktails and Computational analysis)optical clearing technique during Wallerian *** inflammatory factor expression in different polarization states was detected using a protein *** results showed that neutrophil peptide 1 promoted the prolife ration,migration and phagocytosis of macrophages,and CD206 expression on the surfa ce of macrophages,indicating m2 *** axonal debris clearance rate during Wallerian degeneration was enhanced after neutrophil peptide 1 *** peptide 1 also downregulated inflammatory factors interleukin-1α,-6,-12,and tumor necrosis factor-αin invo and in ***,the results suggest that neutrophil peptide 1 activates macrophages and accelerates Wallerian degeneration,which may be one mechanism by which neutrophil peptide 1 enhances peripheral nerve regeneration.

关键词： axonal debris inflammatory factors macrophages neutrophil peptide 1 peripheral nerve injury peripheral nerve regeneration rAW 264.7 cells sciatic nerve Wallerian degeneration

Astronomical forcing and sedimentary noise modeling of lake-level changes in the middle Eocene Chezhen Sag,Bohai Bay Basin,eastern China

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Frontiers of Earth Science 2024年第2期18卷 446-459页

作者： Xuwei LUAN Jinliang ZHANG na LI Tao CHEN Long SUN Xuecai ZHANG Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China management Center of Oil and Gas Exploration Sinopec Shengli OilfieldDongying 257000China

The accurate determination of geological age is a key to understanding the history and process of paleolake evolution and oil and gas exploration in continental lake ***,improving the accuracy of geological age has always been a difficult scientific problem.A 609-m-thick,continuous lacustrine mudstone and sandstone succession in Chezhen Sag(eastern China)provides an ideal middle Eocene sedimentary record for establishing a high-resolution stratigraphic chronology *** on spectrum analysis and sliding window spectrum analysis of the natural gamma(Gr)logging data of well Che 271(C271)in Chezhen Sag,the periods of 405 kyr and 40.1 kyr were filtered by a Gaussian bandpass filter,and a“floating”astrochronological time scale(ATS)was *** total number of 405 kyr eccentricity cycles were 13.6 and 40.1 kyr obliquity cycles were 138 which recorded from the upper member 4(Es4U)to the member 3(Es3)of the Eocene Shahejie Formation,and the depositional duration was 5.53 *** Coefficient(COCO)analysis and evolutionary Correlation Coefficient(eCoCo)analysis found that the optimal sedimentary rate of different *** noise simulation revealed the history of paleolake water changes in the middle Eocene in the Chezhen Sag,according to which four sequences are *** study shows that the lake level change of Chezhen Sag in the middle Eocene shows prominent 1.2 myr cycles and an antiphase well-coupled relationship with obliquity ***,we propose a model to explain the relationship between the orbital cycle and lake level change in the continental lake *** the obliquity of the earth increases,the middle and high latitudes of the earth will be closer to the sun,the direct sunlight will be higher,and the meridional sunshine will increase,thus accelerating the evaporation process of lake basin *** the seasonal changes are obvious(maximum period of 1.2 myr ultra-long obliquity),this effect is more signific

关键词： Chezhen Sag cyclostratigraphy astrochronological time scale sedimentary noise

research on physical explosion crater model of high-pressure natural gas pipeline

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PETrOLEUm rESEArCH 2024年第3期9卷 432-438页

作者： Wang, Dongyuan Xu, Shuiying Wang, Zhao Zhou, Yazhe Gao, na China Petr Pipeline Engn Corp Langfang Peoples R China PipeChina Engn Technol Innovat Co Ltd Tianjin Peoples R China Univ Sci & Technol Beijing Sch Civil & Resource Engn Beijing Peoples R China China Petr Pipeline Bur Engn Co Ltd Int Business Dept Langfang Peoples R China

In this study, Hypermesh and LS-DYna numerical simulation software are used to build a multi domain coupling model of natural gas pipeline, including soil, pipeline, TNT explosive and air domain, and the non-reflection boundary conditions are set for the model. The TNT equivalent method is used to convert the physical explosion amount of natural gas pipeline into 1387.38 kg TNT explosive amount. The simulation results show that the physical explosion of pipeline forms an approximate elliptical crater with a width of 12.68 m and a depth of 4.12 m; the TNT equivalent of the model is corrected by comparing the crater simulation value and the size value of the crater calculated by the PrCI empirical formula under the same laying condition, and the correction coefficient is selected as 0.9, and the corrected TNT equivalent is 1248.64 kg; the modified model crater size is 3.72 m deep and 12.66 m wide, compared with the crater size obtained from the field test, the error of crater depth and width calculated by the modified model simulation is 5.7% and 15.5% respectively. (c) 2024 The Authors. Publishing services provided by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/ by-nc-nd/4.0/).

关键词： High-pressure natural gas Pipeline Physical explosion Crater Numerical simulation