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Acta Mechanica Sinica 2011年第5期27卷 649-659页

作者： xiao-hong Wang zheng-Feng Liu xiao-Xia Lu Department of Thermal Science and Energy Engineering University of Science and Technology of China230026 Hefei China

With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic *** a low-order two-scale expansion,applying the mode coupling approximation in the Yakhot-Orszag renormalization group method to analyze the fluctuating field,the Reynolds-average terms in the Reynolds stress transport equation,such as the convective term,the pressure-gradient-velocity correlation term and the dissipation term,are *** numerical examples：turbulent flow past a backward-facing step and the fully developed flow in a rotating channel,are presented for testing the efficiency of the proposed second-order *** these two numerical examples,the proposed model performs as well as the Gibson-Launder （GL） model,giving better prediction than the standard k-ε model,especially in the abilities to calculate the secondary flow in the backward-facing step flow and to capture the asymmetric turbulent structure caused by frame rotation.

关键词： Turbulent modeling Renormalization group Two-scale expansion Reynolds stress transport equation Second-order model

A STUDY ON' SYNCHRONOUS-HI GH-DERIVATIVE SPECTFLUOR—THE DI FFERENTI ATI ON OF CRUDE OIL AND FUEL OIL POLLUTION

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Chinese Chemical Letters 1992年第7期3卷 535-538页

作者： Jian LIU zheng XIE xiao hong zheng Shanghai Environmental Monitoring Center Shanghai 200030

A method of synchronous-high-derivative spectfluor for identification of crude oil and fuel oil pollution is studied. The best operation conditions for the 2nd and 4th deriv, are set. To differentiate oil-spill at riv... 详细信息

关键词： ATI THE DI FFERENTI ATI ON OF CRUDE OIL AND FUEL OIL POLLUTION A STUDY ON SYNCHRONOUS-HI GH-DERIVATIVE SPECTFLUOR DI GH

Simultaneous quantitation of folic acid and 5-methyltetrahydrofolic acid in human plasma by HPLC–MS/MS and its application to a pharmacokinetic study

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Journal of Pharmaceutical Analysis 2015年第4期5卷 269-275页

作者： xiao-hong zheng Li-Yuan Jiang Lan-Ting Zhao Quan-Ying Zhang Li Ding Department of Pharmaceutical Analysis China Pharmaceutical University Medical Faculty Quzhou College of Technology Department of Pharmacy The Second Affiliated Hospital of Soochow University

A sensitive method based on high-performance liquid chromatography-tandem mass spectrometry （LC- MS/MS） has been developed for the simultaneous determination of folic acid （FA） and its active meta- bolite, 5-methyltetrahydrofolic acid （5-M-THF）, in human plasma. The analytes were extracted from plasma with methanol solution containing 10 mg/mL of 2-mercaptoethanol and 0.025% （v/v） ammonium hydroxide. FA and 5-M-THF were more stable after the addition of 2-mercaptoethanol and ammonium hydroxide in the sample preparation procedures of this study than they were in the previously published methods. Chromatographic separation was performed on a Hedera ODS-2 column using a gradient elution system of acetonitrile and 1 mM ammonium acetate buffer solution containing 0.6% formic acid as mobile phase. LC-MS/MS was carried out with an ESI ion-source and operated in the multiple reaction monitoring （MRM） mode. The assay was linear over the concentration ranges of 0.249-19.9 ng/mL for FA, and 5.05-50.5 ng/mL for 5-M-THF. The developed LC-MS/MS method offers increased sensitivity for quantification of FA and 5-M-THF in human plasma and was applicable to a pharmacokinetic study of FA and 5-M-THF.

关键词： Folic acid 5-Methyltetrahydrofolic acid 2-Mercaptoethanol LC-MS/MS Pharmacokinetics

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju zheng Yixin Li Ting Zhang Yanlin Fu Peiyan Long xiao Gao zhengwei Wang Zhizhong Guan xiaolan Qi Wei hong Yan xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

Efficacy and safety of chimeric antigen receptor-T cells in the treatment of B cell lymphoma:a systematic review and meta-analysis

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Chinese Medical Journal 2020年第1期133卷 74-85页

作者： xiao-hong zheng Xi-You Zhang Qian-Qian Dong Feng Chen Shou-Bo Yang Wen-Bin Li Departm ent of Neuro-Oncology Neurosurgery CenterBeijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Department of Nephrology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of General Medicine Ningbo Medical CenterLi Huili HospitalNingboZhejiang 315000China

Background:Conventional treatment has limited efficacy in relapsed/refractory B-cell *** chimeric antigen receptor T-cell(CAR-T)technology has shown high safety and results in high remission rates,we investigated its efficacy and safety in B-cell lymphoma treatment and analyzed potential affecting factors to provide evidence for therapeutic strategies and ***:We searched databases including PubMed,Embase,and Cochrane up to July ***-analysis 1 was conducted to study the efficacy of CAR-T cell for treating B-cell lymphoma,measuring the response rate and complete remission rate as ***-group analysis was performed for age,pathological type,target antigen,co-stimulatory molecule,and conditioning ***-analysis 2 was undertaken on the safety of the treatment with the incidence rate of toxicity(cytokine-releasing syndrome[CRS],neurotoxicity)as an ***:Seventeen studies were included in the systematic review and *** was found that CAR-T cells had good therapeutic effects in the following cases:B-cell lymphoma(patients≥65 years old);diffuse large B-cell lymphoma pathological type;patients with treatment target antigen other than CD19;patients treated with co-stimulatory molecules other than CD28,including 4-1BB+CD28 or 4-1BB;and patients treated with cyclophosphamide/fludarabine pre-treatment protocol conditioning *** the CRS and neurotoxicity incidences were high,most were reversible with minimal risk of ***:CAR-T cell treatment is safe for clinical application;however,toxicity effects should be monitored.

关键词： Lymphoma B-cell Meta-analysis Chimeric antigen receptor T-cell

Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 141-151页

作者： FAN Yanan WEI hong zheng hongyong DU hongxiu Department of Architecture and Environmental Engineering Taiyuan UniversityTaiyuan 030032China College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030032China

Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal *** electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise *** equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious *** results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical ***,the incorporation of graphite in the material reduces its *** fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive *** volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6%and 6%,*** was determined using the mutation point of each circuit element parameter as the percolation *** addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material.

关键词： cementitious composites conductive fillers electrothermal properties electrochemical impedance spectroscopy

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课植农桑:唐代乡村基层组织与农业生产

中国农史 2021年第1期40卷 56-67页

作者：萧正洪陕西师范大学历史文化学院陕西西安710062

唐代中央集权体制下的乡村基层组织具有督导农业生产发展的法定职责,其历史必要性来自于均田制和租庸调制的实施。按比户口、检察非违、课植农桑和催驱赋役等各项职责皆具有重要的农业经济意义。其中课植农桑一项,最为典型地反映了唐政... 详细信息

唐代中央集权体制下的乡村基层组织具有督导农业生产发展的法定职责,其历史必要性来自于均田制和租庸调制的实施。按比户口、检察非违、课植农桑和催驱赋役等各项职责皆具有重要的农业经济意义。其中课植农桑一项,最为典型地反映了唐政府对于农业生产的强制性干预,它在资源分配、效率评估和农民经济行为选择等多个方面得到体现。随着均田制的瓦解和租庸调制为两税法所替代,乡村基层组织由上层指定的督导农业生产的功能逐渐失去制度性的依据与内在动力,并在后来的历史发展中趋于消亡。

关键词：唐代乡村基层组织课植农桑农业生产

传统农民与环境理性──以黄土高原地区传统农民与环境之间的关系为例

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陕西师范大学学报（哲学社会科学版） 2000年第4期29卷 83-91页

作者：萧正洪陕西师范大学历史文化学院陕西西安710062

明清时期黄土高原不同地区的传统农民具有相类似的经济理性，但在环境理性方面存在着较大的差异。这一现象具有深刻的制度性根源。通过产权和乡村社会组织的制度创新，传统农民有可能避免环境资源利用的无效率。

关键词：环境理性制度创新黄土高原地区传统小农经济理性粗放耕作方式水利灌溉环境效率资源利用

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： zheng Weilin WANG Qijiao xiao Huahua CHEN xiaoxiao XIE Fan ZENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

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武术套路运动员身体训练控制方法的研究

武汉体育学院学报 2005年第5期39卷 85-87页

作者：肖红征武汉体育学院竞技体育学院湖北武汉430079

采用综合性研究方法,对高水平武术套路运动员的机能状况(有氧耐力、无氧耐力)与运动能力(力量、速度、灵敏和柔韧等)以及专项技术训练方面的问题进行了探讨,旨在为高水平武术套路运动员的身体训练实施有效的控制提供理论与实践依据。

关键词：武术套路运动员身体训练控制方法