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考虑风热耦合作用特大型冷却塔内吸力及流场作用机理研究

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工程力学 2017年第12期34卷 112-119,142页

作者：余玮柯世堂南京航空航天大学土木工程系江苏南京210016

已有关于冷却塔内吸力取值的研究均忽略了周边散热器产生的热源影响,以国内在建世界最高220 m特大型间接空冷塔为对象,基于计算流体动力学方法对风热耦合作用下的塔筒内部流场进行数值模拟。在此基础上,对比分析了考虑风热耦合效应特大... 详细信息

已有关于冷却塔内吸力取值的研究均忽略了周边散热器产生的热源影响,以国内在建世界最高220 m特大型间接空冷塔为对象,基于计算流体动力学方法对风热耦合作用下的塔筒内部流场进行数值模拟。在此基础上,对比分析了考虑风热耦合效应特大型冷却塔内表面风荷载的三维效应,归纳总结了内压系数沿子午向和环向的分布规律,探讨了考虑温度场后塔内流场特性、压力系数、阻力系数及风阻的差异及产生原因,最后给出了风热耦合作用下特大型冷却塔内吸力的取值建议。结果表明:考虑风热耦合作用后冷却塔内压系数取值增大,同时阻力系数取值及进出风口压差增大。研究建议此类特大型冷却塔在真实风热耦合环境下内压系数取为-0.43。

关键词：特大型冷却塔风热耦合作用数值模拟内吸力流场特性

基于大涡模拟增设气动措施冷却塔风荷载频域特性

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浙江大学学报（工学版） 2016年第11期50卷 2143-2149页

作者：柯世堂朱鹏南京航空航天大学土木工程系江苏南京210016

为了研究带气动措施的大型冷却塔风荷载频域特性,采用大涡模拟(LES)技术计算得到不同气动措施下冷却塔外表面风荷载时程,将典型断面的平均和脉动风压与国内外实测及风洞试验结果进行对比,验证了大涡模拟的有效性.对平均风压分布曲线、... 详细信息

为了研究带气动措施的大型冷却塔风荷载频域特性,采用大涡模拟(LES)技术计算得到不同气动措施下冷却塔外表面风荷载时程,将典型断面的平均和脉动风压与国内外实测及风洞试验结果进行对比,验证了大涡模拟的有效性.对平均风压分布曲线、典型断面涡量图、脉动风荷载的功率谱、相关系数及相干函数等频域特性进行研究,分析不同气动措施对大型冷却塔外表面平均风压流场特性和脉动风压频域特性的影响.结果表明:增设气动措施导致塔筒下部进风口区域平均风压局部增大,以弧形导风板最明显;脉动风荷载能量主要集中在低频区域,迎风面测点脉动风能量相对较大;增设气动措施导致塔筒表面风荷载频谱特性更加复杂,风荷载功率谱出现多个峰值点;迎风区测点之间脉动风压相关性较高,增设气动措施对相关系数影响较大,其中导风板的相关系数均达到了0.62以上;测点之间相干性均表现出随频率上升而增大的趋势,并且频率达到0.4Hz后,相干函数接近1.

关键词：大型冷却塔气动措施大涡模拟流场分布频域特性

基于最大周向应变断裂准则定向射孔水力裂缝扩展研究

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岩土力学 2019年第11期40卷 4543-4553页

作者：董卓唐世斌大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 大连理工大学岩石破裂与失稳研究所辽宁大连116024

利用最大周向应变断裂准则,基于裂纹扩展增量法模拟水力裂缝扩展过程。数值模拟结果表明,上述裂缝扩展方法能有效模拟水力裂缝扩展过程。在此基础上利用该方法分析了定向射孔水力裂缝初始起裂水压、扩展路径和裂缝"偏转角"受射孔长度与... 详细信息

利用最大周向应变断裂准则,基于裂纹扩展增量法模拟水力裂缝扩展过程。数值模拟结果表明,上述裂缝扩展方法能有效模拟水力裂缝扩展过程。在此基础上利用该方法分析了定向射孔水力裂缝初始起裂水压、扩展路径和裂缝"偏转角"受射孔长度与倾角、地应力差、泊松比和注水压力的影响。通过预测裂缝初始起裂水压和扩展路径,可以优化选择合适的射孔参数。减小地应力差有助于降低裂缝起裂水压,同时可以使裂缝在扩展过程中沟通更大的有效储层。泊松比在临界荷载条件下对裂缝起裂特性产生显著影响,但是在高水压条件下对裂缝扩展路径无明显影响。敏感性分析表明,射孔倾角是影响压裂效果的关键性因素。对上述多因素的影响分析可以为定向射孔水力压裂设计与施工提供重要的参考依据。

关键词：断裂力学最大周向应变准则定向射孔扩展路径泊松比

Bone marrow mesenchymal stem cells induce M2 microglia polarization through PDGF-AA/MANF signaling

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World Journal of Stem Cells 2020年第7期12卷 633-657页

作者： Fan Yang Wen-Bin Li Ye-Wei Qu Jin-Xing Gao Yu-shi tang Dong-Jie Wang Yu-Jun Pan Department of Neurology The First Clinical College of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina Department of Respiratory Medicine The First Clinical College of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain ***,the regulatory mechanism of BMSCs on microglia/macrophages after ischemic stroke is *** evidence suggests that mesencephalic astrocyte-derived neurotrophic factor(MANF)and plateletderived growth factor-AA(PDGF-AA)/MANF signaling regulate M1/M2 macrophage *** To investigate whether and how MANF or PDGF-AA/MANF signaling influences BMSCs-mediated M2 *** We identified the secretion of MANF by BMSCs and developed transgenic BMSCs using a targeting small interfering RNA for knockdown of MANF *** a rat middle cerebral artery occlusion(MCAO)model transplanted by BMSCs and BMSCs-microglia Transwell coculture system,the effect of BMSCsinduced downregulation of MANF expression on the phenotype of microglia/macrophages was tested by Western blot,quantitative reverse transcription-polymerase chain reaction,and ***,microglia were transfected with mimics of miR-30a*,which inuenced expression of X-box binding protein(XBP)1,a key transcription factor that synergized with activating transcription factor 6(ATF6)to govern MANF *** examined the levels of miR-30a*,ATF6,XBP1,and MANF after PDGF-AA treatment in the activated *** Inhibition of MANF attenuated BMSCs-induced functional recovery and decreased M2 marker production,but increased M1 marker expression in vivo or in ***,PDGF-AA treatment decreased miR-30a*expression,had no influence on the levels of ATF6,but enhanced expression of both XBP1 and *** BMSCs-mediated MANF paracrine signaling,in particular the PDGF-AA/miR-30a*/XBP1/MANF pathway,synergistically mediates BMSCs-induced M2 polarization.

关键词： Mesencephalic astrocyte-derived neurotrophic factor Bone marrow mesenchymal stem cell Microglia/macrophage polarization Endoplasmic reticulum stress Cerebral ischemia/reperfusion injury

Development of the real-time double-ring fusion neutron time-of-flight spectrometer system at HL-2M

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Nuclear Science and Techniques 2019年第12期30卷 22-30页

作者： Bo-Wen Zheng Wei Zhang Tong-Yu Wu Si-Cheng Huang Yi-Po Zhang Xiu-Feng Xu shi-Biao tang Ze-Jie Yin State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Southwestern Institute of Physics Chengdu 610041China

A real-time double-ring neutron time-of-flight(TOFII) spectrometer system has been proposed to achieve plasma diagnosis on HL-2M tokamak with a relatively high count rate and sufficient energy *** TOFII system is in its development stage,and this work describes its characteristics in terms of design principle,system structure,electronic system design,preliminary tests,and neutron transport *** preliminary test results illustrate that the TOFII system can demonstrate the realtime dynamic spectrum every 10 *** results also show that based on the support vector machine method,the n-γ discrimination algorithm achieves the discrimination accuracy of 99.1%with a figure of merit of 1.30,and the intrinsic timing resolution of the system is within 0.3%.The simulated flight time spectrums from 1 to 5 MeV are obtained through the Monte Carlo tool Geant4,which also provide the reasonable *** TOFII system will then be calibrated on mono-energetic neutron sources for further verification.

关键词： Time-of-light Neutron spectrometer Geant4 HL-2M

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岩体中的湿度扩散与流变效应分析

采矿与安全工程学报 2010年第3期27卷 292-298页

作者：唐春安唐世斌大连理工大学土木水利学院辽宁大连116024

由于湿度的作用与扩散的范围、时间有关,因此,湿度扩散造成的岩石力学性质劣化和变形随空间和时间而变化,这种变化是造成岩石流变的本源问题.从湿度扩散入手,通过引入湿度增加与材料力学参数弱化的物性关系,建立了湿度-应力-损伤耦合作... 详细信息

由于湿度的作用与扩散的范围、时间有关,因此,湿度扩散造成的岩石力学性质劣化和变形随空间和时间而变化,这种变化是造成岩石流变的本源问题.从湿度扩散入手,通过引入湿度增加与材料力学参数弱化的物性关系,建立了湿度-应力-损伤耦合作用的岩石流变模型.试样蠕变和松弛效应的数值模拟结果再现了湿度扩散条件下岩石力学行为变化的时间效应.通过探讨本文的耦合作用流变模型与传统岩石流变模型之间的差异,进一步阐述了岩石流变行为的本源.

关键词：湿度扩散流变湿度-应力-损伤耦合破坏过程数值模拟

A Transverse-Longitudinal Cross-Spectral Density Matrix of Partially Coherent Electromagnetic Beams

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Chinese Physics Letters 2010年第2期27卷 97-99页

作者：李建龙唐世红吕百达 College of Physical Science and Technology Sichuan University Chengdu 610064 Department of Material Science Sichuan University Chengdu 610064

A transverse-longitudinal cross-spectral density matrix （TLCSDM） of partially coherent electromagnetic beams is proposed. It can extend the traditional Stokes parameters and polarization singularities from the paraxial field to the more general situation. The impact produced by the atmospheric turbulence on polarization singularities of the partially coherent electromagnetic vortex beams is analyzed with the TLCSDM.

关键词： Accelerators beams and electromagnetism Optics quantum optics and lasers Environmental and Earth science

Efficacy of tandospirone in patients with irritable bowel syndrome-diarrhea and anxiety

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World Journal of Gastroenterology 2014年第32期20卷 11422-11428页

作者： Ling Lan Yu-Long Chen Hao Zhang Bai-Ling Jia Yan-Jun Chu Jin Wang shi-Xiao tang Guo-Dong Xia Department of Gastroenterology the People’s Hospital Zhengzhou University Department of Gastroenterology the First Affiliated Hospital Zhengzhou University Department of Gastroenterology the First Affiliated Hospital Luzhou Medical College

AIM: To investigate the efficacy of tandospirone in patients with irritable bowel syndrome-diarrhea (IBS-D) and anxiety in a prospective, randomized, controlled study.

关键词： Irritable bowel syndrome Anxiety Tandospirone Efficacy Safety

Gut microbiota induced abnormal amino acids and their correlation with diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 883-895页

作者： Sheng-Qun Jiang Su-Na Ye Yin-Hua Huang Yi-Wen Ou Ke-Yang Chen Jian-Su Chen shi-Bo tang Aier Eye Hospital Jinan UniversityGuangzhou 510000Guangdong ProvinceChina Aier Eye Institute and Changsha Aier Hospital Changsha 410000Hunan ProvinceChina The First Affiliated Hospital of Bengbu Medical University Bengbu 233000Anhui ProvinceChina School of Public Health Anhui Medical UniversityHefei 230000Anhui ProvinceChina

AIM:To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy(DR)and provide a novel strategy to elucidate the pathological mechanism of ***:The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy(PDR),23 with nonproliferative retinopathy(NPDR),27 without retinopathy(DM),and 29 from the sex-,age-and BMI-matched healthy controls(29 HC)were analyzed by 16S rDNA gene *** fecal samples from PDR,DM,and HC groups were assayed by untargeted *** metabolites were measured using liquid chromatographymass spectrometry(LC-MS)*** between gut microbiota and fecal metabolites were ***:A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR,and the close correlation of the disease progression with PDR-related microbiome and metabolites were *** be specific,the structure of gut microbiota differed in four *** and richness of gut microbiota were significantly lower in PDR and NPDR groups,than those in DM and HC groups.A cluster of microbiome enriched in PDR group,including Pseudomonas,Ruminococcaceae-UCG-002,Ruminococcaceae-UCG-005,Christensenellaceae-R-7,was *** analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC ***,serine,ornithine,and arachidonic acid were significantly enriched in PDR group,while proline was enriched in HC *** analysis illustrated that arginine biosynthesis,lysine degradation,histidine catabolism,central carbon catabolism in cancer,D-arginine and D-ornithine catabolism were elevated in PDR *** analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine,ornithine levels in fecal ***:This study elaborates the different microbiota structure in the gut from four *** relative abundance of

关键词： proliferative retinopathy gut microbiota Ruminococcaceae amino acid metabolism arginine