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Experimental study of drag reduction characteristics related to the multifactor coupling of a bionic jet surface

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Journal of Hydrodynamics 2019年第1期31卷 186-194页

作者： yun-qing Gu song-wei yu Jie-gang Mou Tian-xing Fan Shui-hua Zheng Gang Zhao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

To study the drag reduction of a jet surface,an experiment is conducted with a gyrorotor *** aim of this study is to analyze the influence of the jet aperture,the jet angle and the rotational velocity coupled with the jet velocity on the friction torque acting on a jet surface model by using a jet surface drag reduction testing experimental *** drag reduction characteristics of the jet surface are also *** results show that the maximum drag reduction rate is attained when the jet diameter is 5 mm and the jet velocity is 1.2 m/*** influence of the jet velocity on the drag reduction rate decreases as the diameter ***,the maximum drag reduction rate can be attained when the angle of the jet is 30° and the velocity of the jet is 1.0 m/*** the jet diameter is small,the influence of the jet velocity on the drag reduction rate is small,whereas the maximum drag reduction rate is attained when the jet angle is 30° and the jet velocity is 1.0 m/*** the jet angle is 15°,the drag reduction rate fluctuation is *** maximum drag reduction rate is attained when the rotational velocity is 2 100 r/min and the jet velocity is 1.0 m/*** results show that the best scheme is A2B2D3 A maximum drag reduction rate of 8.57% can be *** effective control of the jet effect on the separation of the boundary layer demonstrates the drag reduction principle of a bionic jet surface.

关键词： Drag reduction bionic jet surface friction torque coupling experiment

Protective effect of cyclophilin A against Alzheimer＇s amyloid beta-peptide （25-35）-induced oxidative stress in PC12 cells

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Chinese Medical Journal 2009年第6期122卷 716-724页

作者： GE yu-song TENG wei-yu ZHANG Chao-dong Department of Neurology First Affiliated Hospital China Medical University Shenyang Liaoning 110001 China

Background β-amyloid peptide （Aβ） is considered responsible for the pathogenesis of Alzheimer＇s disease （AD）. Possible mechanisms underlying Aβ-induced neuronal cytotoxicity include excessive production of reactive oxidative species （ROS） and apoptosis. Cyclophilin A （CypA）, exhibits antioxidant properties and protects neurons against oxidative stress induced injury. This study was conducted to demonstrate whether CyPA added to cultured PC12 cells could alleviate Aβ-induced oxidative stress and protect them from apoptosis.Methods PC12 cells were pre-incubated for 30 minutes with recombinant human cyclophilin A （rhCyPA） in 0.1 nmol/L, 1.0 nmol/L, 10 nmol/L and 100 nmol/L and then incubated with 10 μmol/L Aβ25-35. In every group, cell viability, apoptotic morphology, apoptotic rate, intracellular ROS accumulation, the activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） of PC12 cells and mitochondrial transmembrane potential were detected. Subsequently, the expression of the active form of caspase-3 was determined by Western blotting.Results It was shown that cultures treated with 1.0 nmol/L, 1U nmol/L or 100 nmol/L rnL, rhCyPA＋Aβ25-35 had significantly higher cell viability and a lower rate of apoptosis compared with the cultures exposed only to Aβ25-35. In addition, rhCyPA attenuated Aβ25-35-induced overproduction of intracellular ROS and Aβ25.35-induced a decrease in activity of the key antioxidant enzymes SOD and GSH-Px. Furthermore, rhCyPA also attenuated Aβ25.35-induced mitochondrial dysfunction and the activation of caspase-3.Conclusion CyPA may act as an ROS scavenger, and prevent Aβ25-35-induced neurotoxicity through attenuating oxidative stress induced by Aβ25-35.

关键词： Alzheimer's disease cyclophilin A β-amyloid oxidative stress apoptosis

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin Yang Wanlei Zhao Ruoxuan Zheng Hongqiang Li wei Chen yu-Fei song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Notes on soil dematiaceous hyphomycetes from Mount Taibai and its surrounding area, China Ⅰ

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菌物学报 2008年第1期27卷 16-28页

作者： song wei yu Jin-Feng ZHANG Tian-yu Department of Plant Pathology Shandong Agricultural University Tai ＇an 271018 China

A total of 103 isolates of soil dematiaceous hyphomycetes belonging to 27 species in 15 genera were obtained from soil samples of Mount Taibai and its surrounding area, Shaanxi Province, China. Among them Eladia pachyphialis and Gliomastix pallescens are new species, while Acremoniula sarcinellae, Allescheriella crocea, Chrysosporium merdarium, Chrysosporium pannorum are new records to China. The main distinction between E. pachyphialis and its similar species E. saccula is that the phialide of the former is wider and the conidia are smaller than those of the latter. Gliomastix pallescens is characterized by having light colored, long and unbranched conidiophores by which it can be separated from its similar species, G. cerealis. Latin descriptions are given for the new species. Brief descriptions and illustrations of the new records are also provided based on Chinese isolates. The other 21 species being previously known from China in several genera are also listed. All specimens (dried cultures and slides) and living cultures studied have been deposited in the Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).

关键词：土壤真菌中国新种新记录生物学特征太行山暗色丝孢菌

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo Zheng yu-Tao Zheng Yi-wei Dong Liping Huang Xiaoping Wang wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping yu Emily Choi Michael QJiang Ling wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

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拟南芥H_2O_2突变体的筛选及特性分析

西北植物学报 2009年第5期29卷 888-893页

作者：宋玉伟宋纯鹏南阳师范学院生命科学与技术学院河南南阳473061 河南大学生命科学学院河南开封475001

通过化学诱变剂甲基磺酸乙酯(EMS)诱变模式植物拟南芥(Arabidopsis thaliana)获得突变体筛选群体.在5mmol/LH2O2胁迫下,以叶片温度差异为筛选指标,利用远红外成像技术进行突变体的筛选,获得了对H2O2不敏感突变体hpi1(hydrogen peroxide-... 详细信息

通过化学诱变剂甲基磺酸乙酯(EMS)诱变模式植物拟南芥(Arabidopsis thaliana)获得突变体筛选群体.在5mmol/LH2O2胁迫下,以叶片温度差异为筛选指标,利用远红外成像技术进行突变体的筛选,获得了对H2O2不敏感突变体hpi1(hydrogen peroxide-insensitive1)和敏感突变体hps1(hydrogen peroxide-sensitive1).进一步研究发现,两种突变均为单基因隐性突变,气孔密度同野生型一样,而叶片温度、气孔开度和叶片失水率则有明显的差异.种子萌发实验表明,hpi1对甘露醇(Man)和NaCl不敏感而对ABA敏感,hps1则对3种胁迫都表现出敏感特性.

关键词：拟南芥远红外热像仪 H2O2 突变体筛选

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang wei-wei Wang Mei-Qian Fu Hong-Bing Mo wei-Dong yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG Jian wei Chao yuAN Bin yu Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss