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Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

Journal of Thermal Science 2024年第1期33卷 138-157页

作者： CAO Zhiyuan WANG chuxuan SONG Zhigao GAO Xi zhao Wei LIU Bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi'an 710072China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100080China

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary flows.Nevertheless,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage environment.This paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine cascade.To model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine cascade.The NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming vortex.Numerical simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric endwall.This paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary flow.The results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3%,and 45.7%,respectively.It is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine cascade.With incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2%,respectively.Under some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline cascade.The incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe vortex.Under all the pitchwise locations,NAEP can suppress the secondary vortices,e.g.,the passage vortex and the c

关键词： non-axisymmetric endwall secondary flow incoming vortex passage vortex stage environment

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Dynamic thermo-mechanical responses of road-soft ground system under vehicle load and daily temperature variation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1722-1731页

作者： chuxuan Tang Jie Liu Zheng Lu Yang zhao Jing Zhang Yinuo Feng State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Xinjiang Transportation Planning Survey and Design Institute Co. Ltd.Urumqi830006China Hubei Key Laboratory of Geo-Environmental Engineering Wuhan430071China

A complete road-soft ground model is established in this paper to study the dynamic responses caused by vehicle loads and/or daily temperature variation.A dynamic thermo-elastic model is applied to capturing the behavior of the rigid pavement,the base course,and the subgrade,while the soft ground is characterized using a dynamic thermo-poroelastic model.Solutions to the road-soft ground system are derived in the Laplace-Hankel transform domain.The time domain solutions are obtained using an integration approach.The temperature,thermal stress,pore water pressure,and displacement responses caused by the vehicle load and the daily temperature variation are presented.Results show that obvious temperature change mainly exists within 0.3 m of the road when subjected to the daily temperature variation,whereas the stress responses can still be found in deeper places because of the thermal swelling/shrinkage deformation within the upper road structures.Moreover,it is important to consider the coupling effects of the vehicle load and the daily temperature variation when calculating the dynamic responses inside the road-soft ground system.

关键词： Dynamic response Vehicle load Daily temperature variation Thermo-poroelastic medium Coupling effects

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Insights into the dwarfing mechanism of pear(Pyrus betulaefolia) based on anatomical and structural analysis using X-ray scanning

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Horticultural Plant Journal 2024年第2期10卷 355-366页

作者： Lili Dong chuxuan Yang Jing Wang Jingjing Li Mei zhao Dingli Li Zhiyun Qiu Chunhui Ma Zhenhua Cui College of Horticulture Qingdao Agricultural UniversityQingdaoShandong 266109China College of Landscape and Forestry Qingdao Agricultural UniversityQingdaoShandong 266109China

The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the present study, the rootstock of the dwarf-type pear (Pyrus betulaefolia)PY-9’ was identified and used as the material for anatomical analysis.PY-9’ grew to half the tree height of the normal cultivar Zhengdu’, along with fewer internodes and shorter length. Significant differences in growth rate betweenPY-9’ andZhengdu’ were detected at approximately 30 days after full bloom, which corresponded with the time of the greatest difference in water potential between the dwarf and normal cultivar.PY-9’ showed a higher photosynthetic rate thanZhengdu’. Anatomical analysis showed thatPY-9’ had higher area ratios of both phloem and xylem and more developed vascular tissues thanZhengdu’. The three-dimensional reconstructed skeleton of the xylem from X-ray computed tomography scanning revealed greater intervessel connectivity inZhengdu’ than inPY-9’, which could contribute to the more vigorous growth ofZhengdu’. This study thus provides the first comparison of the microstructural properties of xylem elements between a dwarfing-type and vigorous-type pear rootstock, providing new insights into the dwarfing mechanism in pear and facilitating breeding of dwarf pear rootstocks to increase crop productivity.

关键词： Pyrus betulaefolia Anatomical analysis Dwarfing mechanism Intervessel connectivity Rootstock

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Occurrence and Health Risk of Perfluoroalkyl Acids in Popular Shellfish from a Typical Coastal Area of the East China

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Chemical Research in Chinese Universities 2023年第3期39卷 492-501页

作者： LIU Ruolin LIU Mei zhao chuxuan FU Jianjie ZHOU Wei ZHANG Qinghua Martin HANSEN DONG Yin Sino-Danish College University of Chinese Academy of SciencesBeijing100049P.R.China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085P.R.China School of Environment and Health Jianghan UniversityWuhan430056P.R.China Environmental Metabolomics Lab Department of Environmental ScienceAarhus UniversityFrederiksborgvej 3994000RoskildeDenmark The People’s Hospital of Yuhuan Yuhuan317600P.R.China

As crucial homologous members of per-and polyfluoroalkyl substances(PFASs),perfluoroalkyl acids(PFAAs)have aroused wide public concern because of their unique properties(persistence,bioaccumulation,long-distance migration and toxicity).Studies have shown their potential hazard to wildlife and humans,with food consumption as one of the primary routes of PFAA exposure for general population,especially seafood intake.In this study,17 PFAAs were quantified in 9 shellfish species from Yuhuan City,a typical coastal area of the East China.The total mean concentrations of PFAAs were in the range of 5.03–381 ng/g dry weight(dw),with the highest concentration found in Neverita didyma and the lowest in Babylonia lutosa.Concentrations and composition profiles of PFAAs varied significantly among different species,indicating differences in the bioaccumulation potential of PFAAs among species.Perfluorooctanoic acid(PFOA)was presented as the most abundant PFAA in this study,followed by perfluorobutanoic acid(PFBA).Significant positive correlations were observed among some individual PFAAs(p<0.05),indicating that they may share similar pollution sources or undergo similar compound behaviors.Health risk assessment indicated a relatively high threat for local residents exposed to PFAAs through shellfish consumption.

关键词： Perfluoroalkyl acid Shellfish East China Sea Occurrence Health risk assessment

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高压大功率IGBT器件绝缘结构的电场计算研究综述

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中国电机工程学报 2024年第1期44卷 214-230,I0018页

作者：刘招成崔翔李学宝马楚萱赵志斌新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206

随着高压直流输电技术的发展,高压大功率绝缘栅双极型晶体管(insulated gate bipolar transistor,IGBT)器件被广泛应用于各类高压大容量电力换流和控制装备中。然而,在高压大功率IGBT器件的研制过程以及工程应用中,器件内部局部放电现... 详细信息

随着高压直流输电技术的发展,高压大功率绝缘栅双极型晶体管(insulated gate bipolar transistor,IGBT)器件被广泛应用于各类高压大容量电力换流和控制装备中。然而,在高压大功率IGBT器件的研制过程以及工程应用中,器件内部局部放电现象乃至击穿现象频繁发生,给器件绝缘设计带来巨大挑战。要想实现良好器件绝缘设计,就需要获得器件内部的电场分布,因此实现器件内部电场的准确计算至关重要。文中全面回顾器件内部绝缘结构的建模和计算方法的发展历程,从封装绝缘电场计算、芯片绝缘电场计算以及芯片和封装绝缘耦合电场计算3个方面介绍相关研究的发展历程、适用范围以及相应的不足,最后展望未来器件内绝缘结构电场计算的发展方向。

关键词：绝缘栅双极型晶体管器件绝缘封装结构芯片终端电场计算模型边值问题

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OsGSK2与OsGLK1互作调控水稻叶绿素合成与叶绿体发育

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植物遗传资源学报 2024年第3期25卷 472-481页

作者：赵楚瑄纪晓楠刘梦雨韩丹许可可刘喜淮阴师范学院生命科学学院江苏淮安223300

叶绿素是水稻光合作用的重要色素,叶绿素的合成决定光合作用的效率,影响植物的产量和品质。在本研究中,发现糖原合成酶激酶OsGSK2过表达植株Go-2成熟期呈现叶片深绿色的表型。相比野生型,Go-2植株叶绿素a、叶绿素b以及类胡萝卜素含量显... 详细信息

叶绿素是水稻光合作用的重要色素,叶绿素的合成决定光合作用的效率,影响植物的产量和品质。在本研究中,发现糖原合成酶激酶OsGSK2过表达植株Go-2成熟期呈现叶片深绿色的表型。相比野生型,Go-2植株叶绿素a、叶绿素b以及类胡萝卜素含量显著升高。透射电镜观察结果显示,相比野生型,Go-2植株叶绿体类囊体片层增多。酵母双杂交“一对一”实验证实OsGSK2与Golden2-Like转录因子OsGLK1存在互作,并进一步通过双分子荧光互补实验确认OsGSK2与OsGLK1存在互作。在水稻原生质体中检测双荧光素酶活性发现,相比单转OsGLK1,OsGSK2与OsGLK1共转显著提高下游靶基因的表达水平。荧光定量PCR结果表明,相比野生型,在Go-2植株中OsGLK1直接调控的靶基因OsPORB、OsCAO1、LHCB6等转录水平显著上调。研究结果初步揭示了OsGSK2与OsGLK1互作调控水稻叶绿素合成和叶绿体发育的分子机理,进一步拓展了水稻糖原合成酶激酶的分子功能,丰富了水稻叶色调控的分子网络,为水稻高光合分子育种提供了理论依据。

关键词：水稻 OsGSK2 OsGLK1 叶绿素合成叶绿体发育

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结合型式对地铁车站上盖物业的振动响应影响

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西南交通大学学报 2024年第3期59卷 653-662页

作者：许炜萍刘易然黄谦刘旭赵楚轩王呼佳杨朋孙克国西南交通大学土木工程学院四川成都100191 中铁二院重庆勘察设计研究院有限责任公司重庆400023 中国铁路设计集团有限公司天津300308 中铁二院工程集团有限责任公司四川成都610031

为研究地铁振动对不同结合类型地铁车站及其上方的动力反应影响,基于地铁车站与上盖物业连接型式的主要承载区别,提出“软结合”“硬结合Ⅰ”“硬结合Ⅱ”3种结合型式;然后,采用车-轨耦合模型得到列车荷载谱,利用有限差分软件FLAC^(3D)... 详细信息

为研究地铁振动对不同结合类型地铁车站及其上方的动力反应影响,基于地铁车站与上盖物业连接型式的主要承载区别,提出“软结合”“硬结合Ⅰ”“硬结合Ⅱ”3种结合型式;然后,采用车-轨耦合模型得到列车荷载谱,利用有限差分软件FLAC^(3D)建立地铁车站-上盖物业数值仿真模型,并与实测数据进行对比,验证数值仿真模型与参数的正确性;最后,基于数值仿真,从时域、频域出发,研究3种结合型式下上盖物业的振动响应.研究结果表明:软结合型式下站厅层到上盖物业一层加速度峰值减小69.10%,硬结合Ⅰ型减小2.08%,硬结合Ⅱ型增大2.94%,硬结合型式下上盖物业振动加速度较软结合型式大;3种结合型式下上盖物业振动的频率主要在40~90 Hz,且对于上盖物业同一楼层,振动随距振源距离的增大而逐渐减小;软结合型式下上盖物业一层加速度级最大值为68.2 dB,较站厅层减小11.3 dB;硬结合Ⅰ型、硬结合Ⅱ型的上盖物业加速度级最大值分别为83.4、79.4 dB;地铁振动造成上盖物业附加第一主应力很小,且在向上传播过程中衰减很快;从站厅层到上盖物业,软结合型式第一主应力衰减85.81%,硬结合Ⅰ、Ⅱ型式分别衰减63.46%、72.27%,间隔土对附加应力有明显衰减作用.在地铁实际建设工程中建议选用软结合型式.

关键词：地铁车站上盖物业列车荷载软结合硬结合振动响应

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Novel biomonitoring method for determining five classes of legacy and alternative flame retardants in human serum samples

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Journal of Environmental Sciences 2023年第9期131卷 111-122页

作者： Xiaolin Guan Gaoxin Zhang Lingling Meng Mei Liu Liyuan Zhang chuxuan zhao Yingming Li Qinghua Zhang Guibin Jiang Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of Education Key Laboratory of Polymer Materials Ministry of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Endocrinology and Metabology The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014China University of Chinese Academy of Sciences Beijing 100049China

Flame retardants(FRs)are ubiquitous in environment and biota and may pose harm to human health.In recent years,concern regarding legacy and alternative FRs has been intensified due to their widespread production and increasing contamination in environmental and human matrices.In this study,we developed and validated a novel analytical method for simultaneous determination of legacy and alternative FRs,including polychlorinated naphthalenes(PCNs),short-and middle-chain chlorinated paraffins(SCCPs and MCCPs),novel brominated flame retardants(NBFRs),and organophosphate esters(OPEs)in human serum.Serum samples were prepared by liquid-liquid extraction using ethyl acetate,and purified with Oasis®HLB cartridge and Florisil–silica gel columns.Instrumental analyses were carried out using gas chromatography-triple quadrupole mass spectrometry,highresolution gas chromatography coupled with high-resolution mass spectrometry,and gas chromatography coupled with quadrupole time-of-flight mass spectrometry,respectively.The proposed method was validated for linearity,sensitivity,precision,accuracy,and matrix effects.Method detection limits for NBFRs,OPEs,PCNs,SCCPs,and MCCPs were 4.6×10^(–4)–8.6×10^(–2),4.3×10^(–3)–1.3,1.1×10^(–5)–1.0×10^(–4),1.5,and 9.0×10–1 ng/mL,respectively.Matrix spike recoveries ranged from 73%–122%,71%–124%,75%–129%,92%–126%,and 94%–126%for NBFRs,OPEs,PCNs,SCCPs,and MCCPs,respectively.The analytical method was applied for detection of real human serum.CPs were the dominant FRs in serum,indicating CPs were widely presented in human serum and should be pay more attention for their health risk.

关键词： Human serum Biomonitoring Novel brominated flame retardants Organophosphate esters Chlorinated paraffins Polychlorinated naphthalenes

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DDG1 and G Protein α Subunit RGA1 Interaction Regulates Plant Height and Senescence in Rice(Oryza sativa)

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Phyton-International Journal of Experimental Botany 2023年第7期92卷 2051-2064页

作者： Xi Liu chuxuan zhao Di Wang Gen Pan Xiaonan Ji Su Gao Tanxiao Du Yating Feng Wenjing Chen Jiangsu Key Laboratory of Eco-Agricultural Biotechnology around Hongze Lake Regional Cooperative Innovation Center for Modern Agriculture and Environmental ProtectionHuaiyin Normal UniversityHuai’an223300China School of Life Sciences Huaiyin Normal UniversityHuai’an223300China Crop Research and Development Center Huaiyin Institute of Agricultural Sciences of Xuhuai Region in JiangsuHuai’an223001China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangsha410205China

Many studies have already shown that dwarfism and moderate delayed leaf senescence positively impact rice yield,but the underlying molecular mechanism of dwarfism and leaf senescence remains largely unknown.Here,using map-based cloning,we identified an allele of DEP2,DDG1,which controls plant height and leaf senescence in rice.The ddg1 mutant displayed dwarfism,short panicles,and delayed leaf senescence.Compared with the wild-type,ddg1 was insensitive to exogenous gibberellins(GA)and brassinolide(BR).DDG1 is expressed in various organs,especially in stems and panicles.Yeast two-hybrid assay,bimolecular fluorescent complementation and luciferase complementation image assay showed that DDG1 interacts with theα-subunit of the heterotrimeric G protein.Disruption of RGA1 resulted in dwarfism,short panicles,and darker-green leaves.Furthermore,we found that ddg1 and the RGA1 mutant was more sensitive to salt treatment,suggesting that DDG1 and RGA1 are involved in regulating salt stress response in rice.Our results show that DDG1/DEP2 regulates plant height and leaf senescence through interacting with RGA1.

关键词： Oryza sativa DDG1 plant height senescence RGA1

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交通荷载作用下非饱和风积沙路基动力响应研究

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土木工程学报 2023年第S1期56卷 194-202页

作者：唐楚轩刘杰冯一诺王轩赵阳卢正中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中国科学院大学北京100049 新疆交通规划勘察设计研究院有限公司新疆乌鲁木齐830006 中冶交通建设集团有限公司北京100081

为了给风积沙路基的设计提供理论基础,建立了包含风积沙路基的多层道路动力学模型,模型中风积沙路基土使用非饱和多孔介质模拟,其它道路层采用弹性介质。首先通过双重Fourier变换求得了不同层在变换域内的解析解,并由道路的层间连续假... 详细信息

为了给风积沙路基的设计提供理论基础,建立了包含风积沙路基的多层道路动力学模型,模型中风积沙路基土使用非饱和多孔介质模拟,其它道路层采用弹性介质。首先通过双重Fourier变换求得了不同层在变换域内的解析解,并由道路的层间连续假设得到了多层道路动力学模型整体的刚度矩阵。然后结合应力边界条件求得了非饱和风积沙路基内动力响应的解。计算中考虑了风积沙路基土体模量随饱和度变化规律以及其土水特征曲线,研究了路基厚度、饱和度以及车辆载重对路基内动力响应的影响。研究发现:风积沙路基饱和度对路基动力响应的影响显著,路基土饱和度从0.45增加到0.75时,路基顶部竖向位移幅值增加49.5%;随着路基厚度增加,路基内的竖向加速度幅值逐渐降低,但路基厚度超过3 m后效果逐渐减弱。基于计算结果,得到了不同饱和度与车辆载重下的非饱和风积沙路基工作区深度预测公式,研究结果可为风积沙路基设计提供参考。

关键词：风积沙路基动力响应非饱和土解析解路基工作区深度

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