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Acta Mathematica Scientia 2024年第4期44卷 1572-1593页

作者： Chunxiao zhang jin zhang School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

For singularly perturbed convection-diffusion problems,supercloseness analysis of the finite element method is still open on Bakhvalov-type meshes,especially in the case of *** difficulties arise from the width of the mesh in the layer adjacent to the transition point,resulting in a suboptimal estimate for *** analysis techniques cannot handle these difficulties *** fill this gap,here a novel interpolation is designed delicately for the smooth part of the solution,bringing about the optimal supercloseness result of almost order 2 under an energy norm for the finite element *** theoretical result is uniform in the singular perturbation parameterεand is supported by the numerical experiments.

关键词： singularly perturbed convection-diffusion finite element method supercloseness Bakhvalov-type mesh

Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 495-508页

作者： YANG Luyi LI Haiyang zhang jin ZHU Yuehe College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Astronauts Research and Training Center Beijing 100094China Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency

Effect of Shape and Placement of Twisted Pin Fins in a Rectangular Channel on Thermo-Hydraulic Performance

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Journal of Thermal Science 2024年第5期33卷 1773-1793页

作者： LI Yong zhang jin zhang Yingchun zhang Jiajie MA Suxia SUNDEN Bengt XIE Gongnan College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Cleaner Intelligent Control on Coal&Electricity Ministry of EducationTaiyuan 030024China Shanxi Provincial Key Laboratory of High Efficiency Heat Storage and Low Carbon Heat Supply Taiyuan 030008China School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Department of Energy Sciences Lund UniversityP.O.Box 118Lund SE 22100Sweden School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China

To enhance the thermo-hydraulic performance of cooling channels,this investigation examines the influence of distinct cross-sectional shapes(i.e.,triangular,rectangular,and hexagonal)of twisted pin fins and their arrangements in straight and cross *** ambient air cooling test platform was established to numerically and experimentally investigate the flow and heat transfer characteristics of 360°twisted pin fins at Re=*** findings reveal that straight rows exhibit higher Nu values than cross rows for triangular and rectangular twisted pin fins,and Nu increases with *** contrast,for hexagonal twisted pin fins,only straight rows at Re=19000 exhibit superior overall thermal performance compared to cross ***,the heat transfer performance of the cooling channel with hexagonal twisted fins surpasses both triangular and rectangular configurations,especially at high Reynolds numbers(Re=22800).Although the heat transfer coefficient of the cooling channel with hexagonal twisted fins is significantly enhanced by 132.71%compared to the flat channel,it also exhibits the highest thermal resistance and relative friction among the three types of twisted fins,the maximum of which are 2.14 and ***,the hydrothermal performance factor(HTPF)of the cooling channels with different types of twisted pin fins depends on the Reynolds number and arrangement *** Re=15200,the highest HTPF achieved for the cross-row hexagonal twisted pin fins is 0.99.

关键词： twisted pin fin cross arrangement heat transfer pressure drop HTPF

Kinesin 26B modulates M2 polarization of macrophage by activating cancer-associated fibroblasts to aggravate gastric cancer occurrence and metastasis

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World Journal of Gastroenterology 2024年第20期30卷 2689-2708页

作者： Lian-Meng Huang Ming-jin zhang Department of General Surgery The 901st Hospital of PLAHefei 230031Anhui ProvinceChina

BACKGROUND The regulatory effects of KIF26B on gastric cancer(GC)have been confirmed,but the specific mechanism still needs further ***-cancer analysis shows that the KIF26B expression is highly related to immune infiltration of cancerassociated fibroblasts(CAFs),and CAFs promote macrophage M2 polarization and affect cancers’*** To investigate the regulatory functions of KIF26B on immune and metastasis of *** We analyzed genes’mRNA levels by quantitative real-time polymerase chain *** levels of target proteins were detected by immunohistochemistry,ELISA,and Western *** injected AGS cells into nude mice for the establishment of a xenograft tumor model and observed the occurrence and metastasis of *** degree of inflammatory infiltration in pulmonary nodes was observed through hematoxylin-eosin *** and wound healing assays were performed for the evaluation of cell invasion and migration *** formation assay was used for detecting angiogenesis.M2-polarized macrophages were estimated by immunofluorescence and flow *** KIF26B was significantly overexpressed in cells and tissues of GC,and the higher expression of KIF26B was related to GC metastasis and *** to in vivo experiments,KIF26B promoted tumor formation and metastasis of ***26B expression was positively associated with CAFs’degree of ***,CAFs could regulate M2-type polarization of macrophages,affecting GC cells’migration,angiogenesis,invasion,and epithelial-mesenchymal transition *** KIF26B regulated M2 polarization of macrophage through activating CAFs,regulating the occurrence and metastasis of GC.

关键词： metastasis invasion macrophage

First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics

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Journal of Ocean University of China 2024年第4期23卷 970-980页

作者： LIU Hongwei XING Lei ZHU Henghua zhang jin zhang jing LIU Huaishan Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266071China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Shandong Institute of Geological Survey Jinan 250014China

The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction *** methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling *** this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is ***,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their ***,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking *** from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data.

关键词： first-arrival picking spatial waveform variation label cross-correlation superposition method

Deactivation mechanisms and anti-deactivation strategies of molecular sieve catalysts for NO_(x)reduction

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Chinese Chemical Letters 2024年第3期35卷 8-18页

作者： Fuli Wang Penglu Wang jin zhang Dengchao Peng Mengmeng Wei Dengsong zhang School of Environmental and Chemical Engineering State Key Laboratory of Advanced Special SteelInternational Joint Laboratory of Catalytic ChemistryCollege of SciencesShanghai UniversityShanghai 200444China

Molecular sieve catalysts,owing to their unique chemical properties,are widely used as catalysts among various catalytic *** Br?nsted acid sites in molecular sieve catalysts usually enable active components to disperse well on the catalyst surface,and help to adsorb a large number of gas molecules to achieve maximum catalytic ***,a variety of molecular sieve catalysts have been developed and used in the selective catalytic reduction of NO_(x)by NH_(3)(NH_(3)-SCR).For example,Cu molecular sieve catalysts such as Cu-SSZ-13 and Cu-SAPO-34 with wide temperature windows and stable structure are considered and applied as commercial catalysts for NO_(x)removal in diesel vehicles for a long *** molecular sieve catalysts possess many advantages,they still cannot avoid the serious deactivation caused by various factors in practical *** this review,reasons leading to the deactivation of molecular sieve catalysts for NO_(x)reduction in actual working conditions were *** deactivation mechanisms of molecular sieve catalysts for NO_(x)reduction were analyzed and the corresponding anti-deactivation strategies were ***,challenges and prospects of molecular sieve catalysts for NO_(x)reduction were also proposed.

关键词： Environmental catalysis NO_(x) reduction Molecular sieve catalysts Deactivation mechanism Anti-deactivation

Bifunctional passivation by lewis-base molecules for efficient printable mesoscopic perovskite solar cells

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Journal of Energy Chemistry 2024年第9期96卷 177-184页

作者： Hang Yang Jianhong Zhao Xiaodong Ren Tong Zhou Henbing zhang Weilong zhang jin zhang Guangzhi Hu Yuming zhang Wen-Hua zhang Qingju Liu Yunnan Key Laboratory for Micro/Nano Materials & Technology National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan UniversityKunming 650091YunnanChina Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental Science Yunnan UniversityKunming 650091YunnanChina

Printable mesoscopic perovskite solar cells(PM-PSCs)possess notable merits in terms of cost-effectiveness,easy manufacturing,and large scale ***,the absence of a hole transport layer contributes to the exacerbation of carrier recombination,and the defects between the perovskite and electron transport layer(ETL)interfaces significantly decrease the efficiency of the *** this study,a bifunctional surface passivation approach is proposed by applying a thioacetamide(TAA)surfactant on the mesoporous TiO_(2)*** results demonstrate that TAA molecules could interact with TiO_(2),thereby diminishing the oxygen vacancy ***,the amino group and sulfur atoms in TAA molecules act as Lewis base to effectively passivate the uncoordinated Pb^(2+)in perovskite and improve the morphology of perovskite,and decrease the trap-state density of *** TAA passivation mechanism improves the alignment of energy levels between TiO_(2)and perovskite,facilitating electron transport and reducing carrier ***,the TAA-passivated device achieved a champion power conversion efficiency(PCE)of 17.86%with a high fill factor(FF)of 79.16%and an open-circuit voltage(V_(OC))of 0.971 *** investigation presents a feasible strategy for interfacial passivation of the ETL to further improve the efficiency of PM-PSCs.

关键词： Perovskite solarcells Carbon electrode Thioacetamide Interfacial passivation

Chemico-biological conversion of carbon dioxide

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Journal of Energy Chemistry 2024年第2期89卷 371-387,I0009页

作者： Liangwei Hu Junzhu Yang Qi Xia jin zhang Hongxin Zhao Yuan Lu Zhejiang Province Key Laboratory of Plant Secondary Metabolism and Regulation College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China College of Biological and Chemical Engineering Jiaxing UniversityJiaxing 314000ZhejiangChina

The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse *** address these challenges and work toward carbon(C)neutrality and reduced CO_(2)emissions,the capture and utilization of CO_(2)have become imperative in both scientific research and *** cutting-edge approach to achieving efficient catalytic performance involves integrating green bioconversion and chemical *** innovative strategy offers several advantages,including environmental friendliness,high efficiency,and *** study provides a comprehensive review of existing technical routes for carbon sequestration(CS)and introduces two novel CS pathways:the electrochemicalbiological hybrid and artificial photosynthesis *** also thoroughly examines the synthesis of valuable Cnproducts from the two CS systems employing different catalysts and *** both systems heavily rely on electron transfer,direct and mediated electron transfer has been discussed and summarized in ***,this study explores the conditions suitable for different catalysts and assesses the strengths and weaknesses of *** also explored the biocompatibility of the electrode materials and developed novel *** materials were specifically engineered to combine with enzymes or microbial cells to solve the biocompatibility problem,while improving the electron transfer efficiency of ***,this review summarizes the relevant systems developed in recent years for manufacturing different products,along with their respective production efficiencies,providing a solid database for development in this *** novel chemical-biological combination proposed herein holds great promise for the future conversion of CO_(2)into advanced organic ***,it offers exciting prospects for utilizing CO_(2)in synthesizing

关键词： Carbon dioxide Bioelectric synthesis Artificial photosynthesis Synthetic product

Influence of Micro/Nano-Ti Particles on the Corrosion Behavior of AZ31-Ti Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 484-498页

作者： jinchao Jiao jin zhang Yong Lian Shengli Han Kaihong Zheng Fusheng Pan Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 10083China Beijing Key Laboratory for Corrosion Erosion and Surface Technology Beijing 100083China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 404100China

Adding Ti particles to magnesium alloy simultaneously enhances its strength and ***,how these particles influence on Mg alloy’s corrosion performance is seldom *** corrosion behavior of AZ31-Ti composites containing titanium nanoparticles(1.5 and 5 wt%)and micron particles(10 wt%)prepared by powder metallurgical in 3.5 wt%NaCl solution was *** results indicate that Ti particles serve as the primary location for the cathodic hydrogen reduction reaction,resulting in intense galvanic corrosion between the Ti and Mg *** nanoparticles distributed at the interface of the original AZ31 powder were in a discontinuous mesh structure,thus failing to act as a barrier against *** corrosion products with the existence of numerous cracks gradually peel off during the corrosion process and cannot protect the *** average corrosion rate P_(w) of AZ31,AZ31-1.5%Ti,AZ31-5%Ti,and AZ31-10%Ti after 7 days of immersion is 27.55,105.65,283.67,and 99.35 mm/y,***,AZ31-Ti composites can be considered as potential candidates for degradable fracturing ***,it is recommended to improve their corrosion resistance through surface treatment.

关键词： AZ31-Ti composite Nano-Ti Micro-Ti Corrosion behavior Scanning Kelvin probe force microscopy(SKPFM)

Thoracic spine infection caused by Pseudomonas fluorescens:A case report and review of literature

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World Journal of Clinical Cases 2024年第12期12卷 2099-2108页

作者： Liang Li Bao-Hua zhang jin-Feng Cao Li-jin zhang Ling-Ling Guo Department of Traditional Chinese Medicine Zibo Central HospitalZibo 255000Shandong ProvinceChina Department of Pathology Zibo Central HospitalZibo 255000Shandong ProvinceChina Department of Medical Imaging Zibo Central HospitalZibo 255000Shandong ProvinceChina

BACKGROUND The clinical incidence of spinal infection is gradually increasing,and its onset is insidious,easily leading to missed diagnosis and misdiagnosis,which may lead to serious complications such as nervous system dysfunction,spinal instability and/or deformity,and cause a huge burden on society and *** identification of the causative agent and precision medicine will greatly reduce the suffering of *** present,the main pathogenic bacteria that cause spinal infection are Staphylococcus aureus,Streptococcus,Pneumococcus,Escherichia coli,and *** are no reports of spinal infection caused by Pseudomonas *** SUMMARY We report a 32-year-old female patient with spinal *** presented with flank pain,initially thought to be bone metastases or bone tuberculosis,and had a family background of *** clinical features and changes in imaging and laboratory tests led to the suspicion of thoracic spine *** of the lesion showed inflammation,tissue culture of the lesion was negative several times,and the possible pathogen-Pseudomonas fluorescens was found after gene sequencing of the *** patient recovered completely after a full course of antibiotic *** This report increases the range of pathogens involved in spinal infections,highlights the unique advantages of gene sequencing technology in difficult-todiagnose diseases,and validates conservative treatment with a full course of antibiotics for spinal infections without complications.

关键词： Thoracic spine infection Pseudomonas fluorescens Spinal infection Case report