检索结果-南通市图书馆

Effect of Squealer Tip with Deep Scale Depth on the Aero-thermodynamic Characteristics of Tip Leakage Flow

Journal of Thermal Science 2022年第5期31卷 1773-1789页

作者： BI Shuai wang Longfei wang feilong wang Lei LI Ziqiang Jiangsu Province Key Laboratory of Aerospace Power System Nanjing University of Aeronautics and AstronauticsNanjing210016China

In this paper,the aero-thermal performance of squealer tips with deep-scale depth is numerically investigated in an axial flow turbine,which is compared with the squealer tip with traditional cavity *** methods were validated with experimental *** effect of cavity depth and tip clearance was *** numerical results show that for the squealer tip with conventional cavity depth,the size of the reflux vortex enlarges as the cavity depth *** velocity and uniformity of high entropy production rate(EPR)inside the cavity reduce obviously with the cavity developing into ***,the increase of depth 10%of the blade span(H)leads to enlargement of cavity volume,which increases the total entropy production *** the overall dimensionless entropy production rate(DEPR)of gap and cavity obtains a maximum increase of 43.54%in contrast to the case with 1%H depth *** a result,the relative leakage mass flow rate reduces by 20.6%as the cavity depth increases from 1%to 10%.Given the heat transfer,as the cavity significantly increases to 10%H,the enhanced cavity volume results in a more enormous cavity vortex with low velocity covering the floor,which weakens the convective heat transfer intensity and reduces the area of high heat *** normalized average heat transfer coefficient at the cavity bottom reduces by 40.26%compared to the cavity depth of 1%*** addition,the deep-scale cavity is more effective in inhibiting leakage flow at smaller tip *** reduction amplitude of normalized average heat transfer coefficient at the squealer floor decreases as tip clearance increases,which reduces at most by about 72.6%for the tip clearance of 1%H.

关键词： squealer tip turbine aerothermodynamics tip leakage flow deep-scale depth heat transfer numerical methods

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental Study on Impingement and Film Overall Cooling Characteristics of Turbine Shroud

引用

Journal of Thermal Science 2022年第1期31卷 239-250页

作者： LI Ziqiang wang Longfei MAO Junkui BI Shuai wang feilong College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Based on the variable characteristics of the actual operating conditions of the turbine shroud and the purpose of improving the cooling effect of the turbine shroud,this paper builds a test system of the impingement-film cooling shroud with two gas inlet angles(90°,167°).The effects of film cooling hole arrangement,gas inlet angle,blowing ratio(0.7,1.0,1.5,2.0,2.5,3.0)and temperature ratio(1.2,1.3,1.4,1.5,1.6)on the cooling characteristics of the impingement-film cooling shroud were experimentally studied by infrared temperature measurement technology,especially the effects of gas inlet angle and temperature *** results showed that the film covering effect of the film cooling hole vertical or the same direction of the high-temperature gas incoming flow is better than the film covering effect of the reverse direction with the incoming flow,and the optimal arrangement of film cooling holes can improve the cooling effectiveness of the *** with 90°intake gas,the film coverage area on the shroud surface of the 167°intake gas is expanded,and the surface average overall cooling effectiveness is increased by 1.03%to 12.6%.The overall cooling effectiveness of turbine shroud increases with the increase of blowing ratio,which increases the flow rate and pressure of cooling gas,and the corresponding increase rate is between 1.04%and 9.96%.However,the increase in the temperature ratio increases the mainstream heating capacity,resulting in a decrease in the cooling effectiveness of the shroud,with a maximum reduction rate of 11.04%.

关键词： turbine shroud overall cooling effectiveness impingement-film cooling blowing ratio temperature ratio

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Unsteady analysis of jet impingement under vibration conditions

引用

Chinese Journal of Aeronautics 2022年第5期35卷 291-308页

作者： Yue YANG Junkui MAO feilong wang Xingsi HAN Jiangsu Province Key Laboratory of Aerospace Power System Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The vibration of thermodynamic machinery will affect its cooling *** this research,a high-resolution simulation of jet impingement was performed to quantify the unsteady turbulent convection under vibration conditions.A newly developed Self-Adaptive Turbulence Eddy Simulation(SATES)method was *** Reynolds number was Re=23000,the jet-towall distance was fixed at H/D=2,and the vibrating frequency of the impinging wall f varied from 0 to 200 *** with the static wall case,the maximum enhancement of the stagnation point and area averaged Nusselt number within r/D=1 could reach up to 5%due to the larger primary vortices,whereas it could reduce the heat transfer by 10%beyond r/D=3 due to the suppression of the wall vortices *** on the unsteady analysis and Proper Orthogonal Decomposition(POD)pattern,the modes controlled by vibration were recognized and their contributions to the heat transfer performance were also *** introduction of the vibration promoted the development of the primary vortices and changed the radial alternating motion to a vertical alternating motion at the wall jet *** former was beneficial for the heat transfer,while the latter was unfavorable.

关键词： Impinging jet Proper orthogonal decomposition Self-Adaptive Turbulence Eddy Simulation(SATES) Unsteady turbulent convection Vibration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Comprehensive Review on Mechanisms and Applications of Rare-Earth Based Perovskite Nanocrystals

引用

Chinese Journal of Chemistry 2024年第9期42卷 1032-1056页

作者： Xiaoshan Zhang Yikun wang Xiang Wu feilong wang Qiongrong Ou Shuyu Zhang Academy for Engineering and Technology Institute of Future LightingFudan UniversityShanghai 200433China School of Information Science and Technology Institute for Electric Light SourcesFudan UniversityShanghai 200433China

Rare earth(RE)ions,with abundant 4f energy level and unique electronic arrangement,are considered as substitutes for Pb^(2+)in perovskite nanocrystals(PNCs),allowing for partial or complete replacement of lead and minimizing environmental *** review provides a comprehensive overview of the characteristics of RE-doped PNCs,including up-conversion luminescence,down-conversion luminescence,and quantum confinement effects,***,RE doping has been found to effectively suppress defect formation,reduce nonradiative recombination,enhance photoluminescence quantum yield(PLQY),and even allow for controlling over the morphology of the *** review also highlights the recent advancements in lead-free RE-based perovskites,especially in the case of Eu-based perovskites(CsEuBr_(3) and CsEuCl_(3)).Furthermore,it briefly introduces the applications of PNCs in various fields,such as perovskite solar cells(PSCs),luminescent solar concentrators(LSCs),photodetectors(PDs),and light-emitting diodes(LEDs).A systematic discussion on the luminescence mechanisms of RE-doped PNCs and lead-free RE-based perovskites is provided,along with an outlook on future research *** ultimate goal of this review is to provide guidance for the development of RE-based perovskite optoelectronic devices.

关键词： Perovskite nanocrystals Rare earth Lead-free perovskite lon doping Rare earth-based perovskite nanocrystals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effect on microstructure and plastic deformation behavior of a Zr-based amorphous alloy by cooling rate control

引用

Journal of Materials Science & Technology 2021年第23期82卷 1-9页

作者： feilong wang Dawei Yin Jingwang Lv Shan Zhang Mingzhen Ma Xinyu Zhang Riping Liu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004China

In this study,Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) amorphous alloys samples with the same diameter(8 mm)were prepared by using self-designed molds(*** steel,pure graphite,and copper molds)with different cooling ***,by eliminating the size effect,the effect of the cooling rate on the microstructure and compression deformation behavior of Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) amorphous alloys was *** of the cooling curves revealed that the instantaneous cooling rates of the alloy melt at the glass transition temperature(Tg)are 45,52,and 64 K·s^(-1) for refractory steel,pure graphite,and copper molds,respectively.X-ray diffraction,differential scanning calorimetry,and highresolution transmission electron microscopy analysis revealed that with the decrease in the cooling rate,trace icosahedral-like atomic clusters and nanocrystals appear in local areas of the amorphous alloy and that the amount of free volume decreases with the increase in the amount of icosahedra-like atomic clusters and *** test results revealed that the elastic strain,yield strength,and compressive strength of the amorphous alloy marginally change with the decrease in the cooling rate,while the plastic strain gradually *** fitting,the effective size of the vein-like pattern was linearly related to the enthalpy released during structural relaxation and plastic strain,indicating that at a low cooling rate,the trace nanocrystals in the amorphous alloy could not effectively improve its plasticity and that the amount of free volume mainly affects its plasticity.

关键词： Bulk amorphous alloy Cooling rate Compression plasticity Free volume

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

3D-printed Mg-1Ca/polycaprolactone composite scaffolds with promoted bone regeneration

引用

Journal of Magnesium and Alloys 2024年第3期12卷 966-979页

作者： Xiao Zhao Siyi wang feilong wang Yuan Zhu Ranli Gu Fan Yang Yongxiang Xu Dandan Xia Yunsong Liu Department of Prosthodontics Peking University School and Hospital of StomatologyBeijing 100081China National Center of Stomatology National Engineering Laboratory for Digital and Material Technology of StomatologyNational Clinical Research Center for Oral DiseasesBeijing Key Laboratory of Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijing 100081China Department of Dental Materials Peking University School and Hospital of StomatologyBeijing 100081China

In bone tissue engineering,polycaprolactone(PCL)is a promising material with good biocompatibility,but its poor degradation rate,mechanical strength,and osteogenic properties limit its *** this study,we developed an Mg-1Ca/polycaprolactone(Mg-1Ca/PCL)composite scaffolds to overcome these *** used a melt blending method to prepare Mg-1Ca/PCL composites with Mg-1Ca alloy powder mass ratios of 5,10,and 20 wt%.Porous scaffolds with controlled macro-and microstructure were printed using the fused deposition modeling *** explored the mechanical strength,biocompatibility,osteogenesis performance,and molecular mechanism of the Mg-1Ca/PCL *** 5 and 10 wt%Mg-1Ca/PCL composites were found to have good ***,they promoted the mechanical strength,proliferation,adhesion,and osteogenic differentiation of human bone marrow stem cells(hBMSCs)of pure *** vitro degradation experiments revealed that the composite material stably released Mg_(2)+ions for a long period;it formed an apatite layer on the surface of the scaffold that facilitated cell adhesion and *** tomography and histological analysis showed that both 5 and 10 wt%Mg-1Ca/PCL composite scaffolds promoted bone regeneration bone *** results indicated that the Wnt/β-catenin pathway was involved in the osteogenic ***,Mg-1Ca/PCL composite scaffolds are expected to be a promising bone regeneration material for clinical *** of significance:Bone tissue engineering scaffolds have promising applications in the regeneration of critical-sized bone ***,there remain many limitations in the materials and manufacturing methods used to fabricate *** study shows that the developed Ma-1Ca/PCL composites provides scaffolds with suitable degradation rates and enhanced boneformation ***,the fused deposition modeling method allows precise control of the macroscopic morphology and microsc

关键词： 3D printing Bone tissue engineering Magnesium Osteogenic Polycaprolactone Scaffold.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements

引用

Acta Geologica Sinica(English Edition) 2024年第1期98卷 220-240页

作者： wang Xiang LIU Guangdi SONG Zezhang SUN Mingliang wang Xiaolin wang feilong CHEN Rongtao GENG Mingyang LI Yishu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China China National Offshore Oil Co. Ltd.(CNOOC)Tianjin Branch CompanyTianjin 300459China CNOOC Research Institute Beijing 100028China

The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain *** address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were *** above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater ***,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and *** the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant ***,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial *** OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and *** subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct ***,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace *** established models

关键词： petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sustained release of magnesium and zinc ions synergistically accelerates wound healing

引用

Bioactive Materials 2023年第8期26卷 88-101页

作者： Fan Yang Yijia Xue feilong wang Danni Guo Yunjiao He Xiao Zhao Fanyu Yan Yuqian Xu Dandan Xia Yunsong Liu Department of Prosthodontics Peking University Hospital of StomatologyBeijing100081China National Center for Stomatology National Clinical Research Center for Oral DiseasesNational Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijing Key Laboratory of Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijing100081China Department of Dental Materials Peking University Hospital of StomatologyBeijing100081China

Skin wounds are a major medical challenge that threaten human *** hydrogel dressings demonstrate great potential to promote wound *** this study,magnesium(Mg)and zinc(Zn)are introduced into methacrylate gelatin(GelMA)hydrogel via low-temperature magnetic stirring and photocuring,and their effects on skin wounds and the underlying mechanisms are *** testing confirmed that the GelMA/Mg/Zn hydrogel released magnesium ions(Mg^(2+))and zinc ions(Zn^(2+))in a sustained *** Mg^(2+) and Zn^(2+)not only enhanced the migration of human skin fibroblasts(HSFs)and human immortalized keratinocytes(HaCats),but also promoted the transformation of HSFs into myofibroblasts and accelerated the production and remodeling of extracellular ***,the GelMA/Mg/Zn hydrogel enhanced the healing of full-thickness skin defects in rats via accelerated collagen deposition,angiogenesis and skin wound *** also identified the mechanisms through which GelMA/Mg/Zn hydrogel promoted wound healing:the Mg^(2+) promoted Zn^(2+)entry into HSFs and increased the concentration of Zn^(2+)in HSFs,which effectively induced HSFs to differentiate into myofibroblasts by activating the STAT3 signaling *** synergistic effect of Mg^(2+) and Zn^(2+)promoted wound *** conclusion,our study provides a promising strategy for skin wounds regeneration.

关键词： Biodegradable magnesium Biodegradable zinc GelMA hydrogel Skin wound healing STAT3 signaling pathway

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photocrosslinkable Col/PCL/Mg composite membrane providing spatiotemporal maintenance and positive osteogenetic effects during guided bone regeneration

引用

Bioactive Materials 2022年第7期7卷 53-63页

作者： feilong wang Dandan Xia Siyi wang Ranli Gu Fan Yang Xiao Zhao Xuenan Liu Yuan Zhu Hao Liu Yongxiang Xu Yunsong Liu Yongsheng Zhou Department of Prosthodontics Peking University School and Hospital of StomatologyBeijing100081China National Engineering Laboratory for Digital and Material Technology of Stomatology National Clinical Research Center for Oral DiseasesNational Center of StomatologyBeijing Key Laboratory of Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijing100081China Department of Dental Materials Peking University School and Hospital of StomatologyBeijing100081China Central Laboratory Peking University School and Hospital of StomatologyBeijing100081China

Guided bone regeneration membranes have been effectively applied in oral implantology to repair bone ***,typical resorbable membranes composed of collagen(Col)have insufficient mechanical properties and high degradation rate,while non-resorbable membranes need secondary ***,we designed a photocrosslinkable collagen/polycaprolactone methacryloyl/magnesium(Col/PCLMA/Mg)composite membrane that provided spatiotemporal support effect after *** particles were added to the PCLMA solution and Col/PCLMA and Col/PCLMA/Mg membranes were developed;Col membranes and PCL membranes were used as *** photocrosslinking,an interpenetrating polymer network was observed by scanning electron microscopy(SEM)in Col/PCL and Col/PCL/Mg *** elastic modulus,swelling behavior,cytotoxicity,cell attachment,and cell proliferation of the membranes were *** behavior in vivo and in vitro was monitored according to mass change and by *** membranes were implanted into calvarial bone defects of rats for 8 *** Col/PCL and Col/PCL/Mg membranes displayed much higher elastic modulus(p0.05).The Col/PCL and Col/PCL/Mg membranes had lower degradation rates than the Col membranes,both in vivo and in vitro(p<0.05).The Col/PCL/Mg groups showed enhanced osteogenic capability compared with the Col groups at week 8(p<0.05).The Col/PCL/Mg composite membrane represents a new strategy to display space maintenance and enhance osteogenic potential,which meets clinical needs.

关键词： Guided bone regeneration Magnesium Photocrosslinking Polycaprolactone methacryloyl Collagen

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Study on Voltage Sag Detection of Wind Power System Based on HHT

引用

Energy and Power Engineering 2013年第4期5卷 922-926页

作者： Yanqing Li Ting Yue Hongling Xie feilong wang Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power University Baoding China

For the output of wind power system has the characteristics of randomness, volatility and intermittence, the voltage of wind power system fluctuates frequently and voltage sag is one of the most common voltage fluctuations in wind power system. For the problem of voltage sag of wind power system, the limitations of the detection methods such as the square detection method, the half-wave RMS detection method and wavelet transform are summed up, and a new detecting method named Hilbert-huang Transform(HHT) is put forward in this paper, which can detect the voltage sag accurately and timely. In order to solve the problem of end effect in the process of empirical mode decompostion (EMD), a self-adaptive method named improved waveform matching is applied in dealing with the end issue. Voltage fluctuations are reflected by two parameters named voltage amplitude and frequency of each intrinsic mode function (IMF) in HHT. The practicality of the method is verified by Matlab simulation.

关键词： HHT Wind Power System Voltage Sag Detection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：