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Numerical investigation and modeling of sweep effects on inlet flow field of axial compressor cascades

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Chinese Journal of Aeronautics 2024年第2期37卷 296-308页

作者： Jiancheng zhang Donghai JIN Xingmin gui School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institue of Beihang University Nanchang 330096China

Swept blades are widely utilized in transonic compressors/fans and provide high load,high through-flow,high efficiency,and adequate stall ***,there is limited quantitative research on the mechanism of the effect of swept blades on the flow field,resulting in a lack of direct quantitative guidance for the design and analysis of swept blades in fans/*** better understand this mechanism,this study employs a reduced-dimensional force equilibrium method to analyze more than 1500 swept cascades *** verify that circumferential fluctuation terms are responsible for inducing radial migration in the inlet airflow field of the swept blade,resulting in variations in the incidence angle and consequently leading to changes in the characteristics of the swept ***,a combination of simple functions and machine learning is utilized to model the circumferential fluctuation terms and quantify the sweep *** prediction accuracy of the model is high,with coefficient of determination greater than 0.95 on the test *** the model is applied in a meridional flow analysis program,the calculation accuracy of the program for the incidence angle is improved by 0.4°and 0.6°at the design and off-design conditions respectively,compensating for the program’s original ***,the model can also provide quantitative guidance for the design of swept blades,thereby reducing the number of design iterations and improving design efficiency.

关键词： Turbomachinery Sweep aerodynamics Quasi-3D method Incidence angle Circumferential fluctuation Machine learning

A Spleen Tyrosine Kinase’s Sky in Neuronal Degeneration

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Neuroscience Bulletin 2024年第2期40卷 273-276页

作者： Wan-Yun zhang sen Lin Department of Neurology Xinqiao HospitalThe Second Afliated HospitalArmy Medical UniversityChongqing 400042China Chongqing Institute for Brain and Intelligence Guangyang Bay LaboratoryChongqing 400064China

With the growing elderly population,neurodegenerative disorders like Alzheimer's disease(AD)are emerging as a significant public health *** is widely acknowledged in the scientific community that the accumulation of neurotoxic aggregates,such as amyloid beta(Aβ),within the central nervous system is a major factor in the development of these ***,human genome-wide association studies have identified mutations in microglial receptors that may be linked to a number of neurodegenerative diseases[1].

关键词： Aβ Spleen Alzheimer

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han zhang You Lu Sheng-gui zhang Li zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈EG(u)U{u}φ(z)≠Σz∈EG(v)U{v}φ(z)for each edge uv∈E(G),where EG(u)is the set of edges incident with a vertex *** 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-***,Yang et *** that the conjecture holds for planar graphs withΔ≥10,and Qu et *** that the list version of the conjecture also holds for planar graphs withΔ≥*** this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

Predictive factors and model validation of post-colon polyp surgery Helicobacter pylori infection

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 173-185页

作者： Zheng-sen zhang Health Management Center Affiliated Hospital of Shaoxing University(Shaoxing Municipal Hospital)Shaoxing 312000Zhejiang ProvinceChina

BACKGROUND Recently,research has linked Helicobacter pylori(***)stomach infection to colonic inflammation,mediated by toxin production,potentially impacting colorectal cancer *** To investigate the risk factors for post-colon polyp surgery,*** infection,and its correlation with pathologic *** Eighty patients who underwent colon polypectomy in our hospital between January 2019 and January 2023 were retrospectively *** were then randomly split into modeling(n=56)and model validation(n=24)sets using *** modeling cohort was divided into an ***-infected group(n=37)and an ***-uninfected group(n=19).Binary logistic regression analysis was used to analyze the factors influencing the occurrence of *** infection after colon polyp surgery.A roadmap prediction model was established and ***,the correlation between the different pathological types of colon polyps and the occurrence of *** infection was analyzed after colon polyp *** Univariate results showed that age,body mass index(BMI),literacy,alcohol consumption,polyp pathology type,high-risk adenomas,and heavy diet were all influential factors in the development of *** infection after intestinal *** multifactorial logistic regression analysis showed that age,BMI,and type of polyp pathology were independent predictors of the occurrence of *** infection after intestinal *** area under the receiver operating characteristic curve was 0.969[95%confidence interval(95%CI):0.928–1.000]and 0.898(95%CI:0.773–1.000)in the modeling and validation sets,*** slope of the calibration curve of the graph was close to 1,and the goodness-of-fit test was P>0.05 in the two *** decision analysis curve showed a high rate of return in both *** results of the correlation analysis between different pathological types and the occurrence of *** infection after colon polyp surgery showed that hyperplastic

关键词： Colon polyps Helicobacter pylori Risk factors Pathologic type Columnar graphic modeling

Synthesis of a High-Efficiency Demulsifier and Study on Optimal Demulsification Conditions

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 107-115页

作者： Zhu Shuai zhang YingYu gui Xia College of Chemical Engineering Nanjing Tech University30 Puzhunan RoadNanjing 211816China

Oil and water separation has always been a top priority in the oil *** this study,a series of hyperbranched fluorinated polyamine-amine polymers(HFPA1-5)were synthesized directly using an improved“one-pot method.”The highly active fluorinated p-trifluoromethylaniline was used as the core raw material,while diethylenetriamine and methyl acrylate were used as the chain segment.A hyperbranched fluorine-containing polyamine-amine demulsifier(NHFPA6)was obtained through nano-grafting copolymerization of *** enhance the demulsification and dehydration performance,the copolymerized HFPA6 was modified and ***,the effects of the combination ratio,demulsifier concentration,demulsification time,and demulsification temperature on the demulsification effect were *** results revealed that a combination ratio of DE-401:NHFPA6=1:1,a demulsification temperature of 50℃,a demulsification time of 60 min,and a demulsifier concentration of 150 mg/L yielded a dehydration rate as high as 99.80%.A response surface optimization design of demulsification conditions was *** model verified that the optimal demulsification conditions were 50℃,300 mg/L,and 90 ***,considering the economic benefits of factories,it is more favorable to select demulsification conditions with a shorter time and lower concentration when the dehydration standard is ***,the demulsification conditions were selected as 50℃,150 mg/L,and 60 *** to existing demulsifiers,the demulsifier developed in this study exhibits a lower demulsification temperature and higher demulsification efficiency.

关键词： hyperbranched fluorinated polyamine-amine nano-SiO_(2)

Identification of carbonates with high positive carbon isotope excursion from the Liaohe Group in the northeastern North China Craton and implications for the Lomagundi-Jatuli Event

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Science China Earth Sciences 2024年第9期67卷 2824-2844页

作者： Hongyu WANG Shuanhong zhang sen WANG Linghao KONG Yue ZHAO Qiqi zhang sen GAO Guohui HU Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural Resources SinoProbe Laboratory Chinese Academy of Geological Sciences School of Earth Science and Mineral Resources China University of Geosciences

The Great Oxidation Event（GOE） during the early Paleoproterozoic represents the first significant buildup in Earth's atmospheric oxygen and resulted in a series of significant changes in the Earth's surface environment. Among them is the 2.22（or 2.33）–2.06 Ga Lomagundi-Jatuli Event（LJE）, which is globally, the largest magnitude and longest duration, marine carbonate positive carbon isotope excursion(δ13CV-PDB>10‰) known. This event has attracted the attention of scholars all over the world. However, except for a high positive carbon isotope excursion(δ13CV-PDB>10‰) recently identified from marine carbonate rocks within the Daposhan Formation in the lower Fanhe Group（or the Sanchazi Group） in the Longgang Block in the northeast North China Craton（NCC）, Paleoproterozoic carbonates in the NCC are characterized by a low-amplitude positive carbon isotope excursion(δ13CV-PDB10‰） of marine carbonate rocks occurred at about 2.15 *** comparisons of different s

关键词： Lomagundi-Jatuli Event (LJE) Great Oxidation Event (GOE) Carbon-oxygen isotopes Liaohe Group Marine carbonate Jiao-Liao-Ji Belt North China Craton

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Facile synthesis of suvorexant,an orexin receptor antagonist,via a chiral diazepane intermediate

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Chinese Chemical Letters 2015年第1期26卷 103-107页

作者： Yin Chen Yan Zhou Jun-Hong Li Jia-Quan Sun gui-sen zhang Systems Biology Theme Department of Biomedical EngineeringCollege of Life Science and TechnologyHuazhong University of Science and Technology Jiangsu Nhwa Pharmaceutical Co. Ltd.

A facile synthesis of suvorexant, an orexin receptor antagonist, is described. The key intermediate 6 was prepared from R-3-aminobutyric acid through protection, condensation, deprotection, cyclization, and hydrogenation steps. The title product was obtained with a total yield of 31% （〉99% ee） after eight linear steps using commercially available raw materials.

关键词： Synthesis Suvorexant Chiral diazepane

Unsupervised social network embedding via adaptive specific mappings

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Frontiers of Computer Science 2024年第3期18卷 61-71页

作者： Youming GE Cong HUANG Yubao LIU sen zhang Weiyang KONG School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275China Guangdong Key Laboratory of Big Data Analysis and Processing Guangzhou 510006China

In this paper,we address the problem of unsuperised social network embedding,which aims to embed network nodes,including node attributes,into a latent low dimensional *** recent methods,the fusion mechanism of node attributes and network structure has been proposed for the problem and achieved impressive prediction ***,the non-linear property of node attributes and network structure is not efficiently fused in existing methods,which is potentially helpful in learning a better network *** this end,in this paper,we propose a novel model called ASM(Adaptive Specific Mapping)based on encoder-decoder *** encoder,we use the kernel mapping to capture the non-linear property of both node attributes and network *** particular,we adopt two feature mapping functions,namely an untrainable function for node attributes and a trainable function for network *** the mapping functions,we obtain the low dimensional feature vectors for node attributes and network structure,***,we design an attention layer to combine the learning of both feature vectors and adaptively learn the node *** encoder,we adopt the component of reconstruction for the training process of learning node attributes and network *** conducted a set of experiments on seven real-world social network *** experimental results verify the effectiveness and efficiency of our method in comparison with state-of-the-art baselines.

关键词： network embedding specific kernel mapping attention mechanism

Effect of Ti and Ta content on the oxidation resistance of Co-Ni-based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 351-361页

作者： Yuheng zhang Zixin Li Yunwei gui Huadong Fu Jianxin Xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

Co-Ni-based superalloys are known for their capability to function at elevated temperatures and superior hot corrosion and thermal fatigue ***,these alloys show potential as crucial high-temperature structural materials for aeroengine and gas turbine hot-end *** previous work elucidated the influence of Ti and Ta on the high-temperature mechanical properties of ***,the intricate interaction among elements considerably affects the oxidation resistance of *** this paper,Co-35Ni-10Al-2W-5Cr-2Mo-1Nb-xTi-(5−x)Ta alloys(x=1,2,3,4)with varying Ti and Ta contents were designed and compounded,and their oxidation resistance was investigated at the temperature range from 800 to 1000℃.After oxidation at three test conditions,namely,800℃for 200 h,900℃for 200 h,and 1000℃for 50 h,the main structure of the oxide layer of the alloy consisted of spinel,Cr_(2)O_(3),and Al_(2)O_(3)from outside to *** consisting of Ta,W,and Mo formed below the Cr_(2)O_(3)*** interaction of Ti and Ta imparted the highest oxidation resistance to 3Ti2Ta ***,an excessive amount of Ti or Ta resulted in an adverse effect on the oxidation resistance of the *** study reports the volatilization of W and Mo oxides during the oxidation process of Co-Ni-based cast superalloys with a high Al content for the first time and explains the formation mechanism of holes in the oxide *** results provide a basis for gaining insights into the effects of the interaction of alloying elements on the oxidation resistance of the alloys they form.

关键词： Co-Ni-based superalloys high-temperature oxidation Ti and Ta elements formation mechanism of holes