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A novel high-Cr CoNi-based superalloy with superior high-temperature microstructural stability, oxidation resistance and mechanical properties

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International Journal of minerals,Metallurgy and Materials 2024年第6期31卷 1373-1381页

作者： Xiaorui Zhang min zou Song Lu Longfei Li Xiaoli Zhuang Qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced MetalsUniversity of Science and Technology BeijingBeijing 100083China

A novel multicomponent high-Cr CoNi-based superalloy with superior comprehensive performance was prepared,and the evaluation of its high-temperature microstructural stability,oxidation resistance,and mechanical properties was conducted mainly using its cast polycrystalline *** results disclosed that the morphology of theγ′phase remained stable,and the coarsening rate was slow during the long-term aging at 900–1000℃.The activation energy forγ′precipitate coarsening of alloy 9CoNi-Cr was(402±51)kJ/mol,which is higher compared with those of CMSX-4 and some other Ni-based and Co-based ***,there was no indica-tion of the formation of topologically close-packed phases during this *** these factors demonstrated the superior microstructural stability of the *** mass gain of alloy 9CoNi-Cr was 0.6 mg/cm^(2) after oxidation at 1000℃ for 100 h,and the oxidation resistance was comparable to advanced Ni-based superalloys CMSX-4,which can be attributed to the formation of a continuous Al_(2)O_(3) protective ***,the compressive yield strength of this cast polycrystalline alloy at high temperatures is clearly higher than that of the conventional Ni-based cast superalloy and the compressive minimum creep rate at 950℃ is comparable to that of the conventional Ni-based cast superalloy,demonstrating the alloy’s good mechanical properties at high *** is partially because high Cr is bene-ficial in improving theγandγ′phase strengths of alloy 9CoNi-Cr.

关键词： CoNi-based superalloys microstructure coarsening oxidation mechanical properties

A Bayesian Stepwise Discriminant Model for Predicting Risk Factors of Preterm Premature Rupture of Membranes： A Case-control Study

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Chinese Medical Journal 2017年第20期130卷 2416-2422页

作者： Li-Xia Zhang Yang Sun Hai Zhao Na Zhu Xing-De Sun Xing Jin ai-min zou Yang Mi Ji-Ru Xu Department of Microbiology and Immunology Health Science Center Xi'an Jiaotong University Xi'an Shaanxi 710061 China Deparment of Clinical Laboratory Shaanxi Provincial People's Hospital Xi'an Shaanxi 710068 China Department of Medical Statistics Shaanxi Provincial People's Hospital Xi'an Shaanxi 710068 China Deparment of Clinical Laboratory Xi'an Fourth Hospital Xi'an Shaanxi 710004 China Deparment of Clinical Laboratory Xi'an Gaoxin Hospital Xi'an Shaanxi 710075 China Deparment of Clinical Laboratory Chang'an Hospital Xi'an Shaanxi 710018 China Department of Obstetrics and Gynecology The Northwest Women and Children Hospital Xi'an Shaanxi 710061 China

Background： Preterm premature rapture of membrane （PPROM） can lead to serious consequences such as intrauterine infection, prolapse of the umbilical cord, and neonatal respiratory distress syndrome. Genital infection is a very important risk which closely related with PPROM. The preliminary study only made qualitative research on genital infection, but there was no deep and clear judgment about the effects of pathogenic bacteria. This study was to analyze the association of in fections with PPROM in pregnant women in Shaanxi, China, and to establish Bayesian stepwise discriminant analysis to predict the incidence of PPROM. Methods： In training group, the 112 pregnant women with PPROM were enrolled in the case subgroup, and 108 normal pregnant women in the control subgroup using an unmatched case-control method. The sociodemographic characteristics of these participants were collected by face-to-face interviews. Vaginal excretions fiom each participant were sampled at 28 36-6 weeks of pregnancy using a sterile swab. DNA corresponding to Chlamrdia trachomalix （CT）, Ureaplasma urealyticwn （UU）, Candida albicans, group B streptococci （GBS）, herpes simplex virus- 1 （HSV-1）, and HSV-2 were detected in each participant by real-time polymerase chain reaction. A model of Bayesian discriminant analysis was established and then verified by a mull）center validation group that included 500 participants in the case subgroup and 5（10 participants in the control subgroup from five different hospitals in the Shaanxi province, respectively. Results： The sociological characteristics were not significantly different between the case and control subgroups in both training and validation groups （all P 〉 0.05）. In training group, the infection rates of UU （11.6% vs. 3.7%）, CT （17.0% vs. 5.6%）, and GBS （22.3% vs. 6.5%） showed statistically different between the case and control subgroups （all P 〈 0.05）, Iog-transfomacd quantification of UU, CE GBS, and HSV-2 showed statistically different

关键词： Bayesian Stepwise Discfiminant Analysis EtiologicalFactors Infection Preterm Premature Rupture of Membranes

Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries

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Rare Metals 2024年第5期43卷 2053-2066页

作者： Jia-Mei Lai Zhi-min zou Yu Bai Yu-Tao Xing Chun-Hai Jiang Fujian Provincial Key Laboratory of Functional Materials and Applications Institute of Advanced Energy MaterialsSchool of Materials Science and EngineeringXiamen University of TechnologyXiamen 361024China Shanghai XFH Science and Technology Development Co. Ltd.Shanghai 200949China Fujian XFH New Energy Materials Co. Ltd.Yong'an 366000China Shenzhen XFH Science and Technology Co. Ltd.Shenzhen 518071China Laboratorio de Microscopia Eletronica de Alta Resolucao Centro de Caracterizagao Avangada Para a Industria de Petroleo(LaMAR/CAIPE)Universidade Federal FluminenseNiteroiRJ 24210-346Brazil

Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode ***,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@***,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second *** of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite *** one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB.

关键词： Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability

Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： Ke Yu Wei-min Kong Zhen Zhao ai-Jun Duan Lian Kong Xi-Long Wang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective ***-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic *** as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS *** average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic *** cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active *** embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS *** improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

Potentially Practical Catalytic Systems for Olefin-Polar Monomer Coordination Copolymerization

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CCS Chemistry 2024年第4期6卷 882-897页

作者： Chen Tan min Chen Chen zou Changle Chen Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Environment-Friendly Polymeric Materials of Anhui ProvinceAnhui UniversityHefeiAnhui 230601 CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026

Studies on transition-metal catalyzed olefin-polar monomer coordination copolymerization and their resulting polar-functionalized polyolefin materials have attracted attention from both academia and *** decades of research,recent developments in a variety of high-performance catalytic systems have shown that this field is on the brink of *** review summarizes representative olefin-polar monomer coordination copolymerization catalyst systems that may be suitable for industrial polyolefin production via homogeneous solution-phase processes or heterogeneous gas-phase/slurry-phase processes.

关键词： olefin copolymerization polar monomer catalyst solution polymerization heterogeneous

A Novel Divide and Conquer Solution for Long-term Video Salient Object Detection

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Machine Intelligence Research 2024年第4期21卷 684-703页

作者： Yun-Xiao Li Cheng-Li-Zhao Chen Shuai Li ai-min Hao Hong Qin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Department of Computer Science Stony Brook UniversityNew York 11794USA

Recently,a new research trend in our video salient object detection(VSOD)research community has focused on enhancing the detection results via model self-fine-tuning using sparsely mined high-quality keyframes from the given *** such a learning scheme is generally effective,it has a critical limitation,i.e.,the model learned on sparse frames only possesses weak generalization *** situation could become worse on“long”videos since they tend to have intensive scene ***,in such videos,the keyframe information from a longer time span is less relevant to the previous,which could also cause learning conflict and deteriorate the model ***,the learning scheme is usually incapable of handling complex pattern *** solve this problem,we propose a divide-and-conquer framework,which can convert a complex problem domain into multiple simple ***,we devise a novel background consistency analysis(BCA)which effectively divides the mined frames into disjoint *** for each group,we assign an individual deep model on it to capture its key attribute during the fine-tuning *** the testing phase,we design a model-matching strategy,which could dynamically select the best-matched model from those fine-tuned ones to handle the given testing *** experiments show that our method can adapt severe background appearance variation coupling with object movement and obtain robust saliency detection compared with the previous scheme and the state-of-the-art methods.

关键词： Video salient object detection background consistency analysis weakly supervised learning long-term information background shift.

Synergistic effects of Pleistocene geological and climatic events on complex phylogeographic history of widespread sympatric species of Megaloptera in East Asia

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Zoological Research 2024年第5期45卷 1131-1146页

作者： ai-Li Lin ming-ming zou Li-Jun Cao Fumio Hayashi Ding Yang Xing-Yue Liu Department of Entomology China Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University SanyaHainan 572025China International Joint Laboratory of Taxonomy and Systematic Evolution of Insecta Henan Institute of Science and TechnologyXinxiangHenan 453003China Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Department of Biology Tokyo Metropolitan UniversityHachioji-shiTokyo 192-0397Japan

Unraveling the phylogeographic histories of species remains a key endeavor for comprehending the evolutionary processes contributing to the rich biodiversity and high endemism found in East *** this study,we explored the phylogeographic patterns and demographic histories of three endemic fishfly and dobsonfly species(Neochauliodes formosanus,Protohermes costalis,and Neoneuromus orientalis)belonging to the holometabolan order *** species,which share a broad and largely overlapping distribution,were analyzed using comprehensive mitogenomic *** findings revealed a consistent influence of vicariance on the population isolation of *** and *** between Hainan,Taiwan,and the East Asian mainland during the early Pleistocene,potentially hindering subsequent colonization of the later diverged *** to these ***,we unveiled the dual function of the major mountain ranges in East Asia,serving both as barriers and conduits,in shaping the population structure of all three ***,we demonstrated that these co-distributed species originated from Southwest,Southern,and eastern Central China,respectively,then subsequently migrated along multi-directional routes,leading to their sympatric distribution on the East Asian ***,our results highlighted the significance of Pleistocene land bridges along the eastern coast of East Asia in facilitating the dispersal of mountain-dwelling insects with low dispersal ***,this study provides novel insight into the synergistic impact of Pleistocene geological and climatic events in shaping the diversity and distribution of aquatic insects in East Asia.

关键词： Comparative phylogeography Island biogeography Pleistocene glaciation Corydalidae East Asia

Extrusion-base d 3D-printe d“rolle d-up”composite scaffolds with hierarchical pore structure for bone growth and repair

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Journal of Materials Science & Technology 2024年第4期171卷 222-234页

作者： Yufan Li Li Chen Yijing Stehle mingyue Lin Chenxin Wang Rui Zhang min Huang Yubao Li Qin zou Research Center for Nano Biomaterials Analytical&Testing CenterSichuan UniversityChengdu 610064China Analytical&Testing Center Sichuan UniversityChengdu 610064China Department of mechanical engineering Union College807 Union St.SchenectadyNY 12308USA Sichuan Institute of Atomic Energy Chengdu 610101China

Three-dimensional(3D)bioprinting,specifically direct ink writing(DIW)capable of printing biologically active substances such as growth factors or drugs under low-temperature conditions,is an emerging di-rection in bone tissue ***,limited by the bio-ink mobility and the poor resolution of this printing technology,the lateral pores of current crisscross-stacked scaffolds printed through DIW tend to clog and are inimical to bone ***,it is critical to develop DIW printed biologi-cal scaffold structure with high mechanical strength,porosity,and biocompatibility ***,patterned polylactic acid(PLA)/polycaprolactone(PCL)/nano-hydroxyapatite(n-HA)based scaffold was printed through DIW technological and rolled-up for properties characterization,cytocompatibility test,and bone repair *** result not only shows that the hexagonal patterned scaffolds are me-chanically strong with porosity,but also demonstrated that the hierarchical pore structure formed during rolled-up has the potential to address the clogging problem and stimulates bone growth and repair.

关键词： Direct ink writing(DIW) Bone repair scaffold,Micro-CT Bio composites

Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 79-89页

作者： Ao-Han Li Su Bu Ling Wang ai-min Liang Hui-Yu Luo Department of Anesthesiology Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Cardiothoracic Surgery Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Rehabilitation Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Internal Medicine-Cardiovascular Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric ***,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this *** To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric *** A total of 80 patients were involved in this *** subjects were divided into two groups:Propofol group and sevoflurane *** evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(SAS)and self-rating depression scale(SDS).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also *** The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane ***,the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol *** sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol ***,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol *** Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric *** anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative *** anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental ***,the selection of anesthetic agents should be based on the individual patient's specific circumstances.

关键词： Propofol Sevoflurane Radical resection of gastric cancer Anesthetic effect Cognitive function Negative emotion