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Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

Journal of Thermal Science 2025年第1期34卷 92-109页

作者： LI Lin zhang Jianshe CHEN Caiyan TAN Wei zhang yanfeng Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing 100190China

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS)method,the light gradient-boosting machine algorithm(LightGBM),and a genetic algorithm(GA)to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB)into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10^(5),3.5×10^(5),and 4.5×10^(5) are 16.32%,20.76%,and 22.16%,respectively.

关键词： low Reynolds numbers compressor optimization boundary layer transition

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数智技术赋能农民精神生活共同富裕

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西北农林科技大学学报(社会科学版) 2025年第2期25卷 80-88页

作者：杨逸隆张艳凤西安交通大学马克思主义学院内蒙古农业大学党委宣传部内蒙古农业大学水利与建筑工程学院

将数智技术有机嵌入农民精神生活的运行过程，不仅能够推动农民精神交往场域不断拓展，促进精神文化产品增量提质，更能有效加快精神资源流通速率，进而缩小城乡区域之间人民精神生活的差距，推动全民共享优质精神文化成果。从内在机理... 详细信息

将数智技术有机嵌入农民精神生活的运行过程，不仅能够推动农民精神交往场域不断拓展，促进精神文化产品增量提质，更能有效加快精神资源流通速率，进而缩小城乡区域之间人民精神生活的差距，推动全民共享优质精神文化成果。从内在机理看，数智技术提升了农民构筑精神家园的“主体性”,驱动农民汇聚向上向善的“正能量”,创造了农民精神文化交往“新模式”,助力农民精神生活运行的“全过程”。然而，数智技术所带来的“技术至上”思潮泛起、“技术鸿沟”加剧、“技术滥用”风险等也成为农民精神生活共同富裕的现实梗阻。未来，要处理好科技应用与人文关怀、供给提质与需求引导、内容丰富与形式创新、现实交往与虚拟交互“四对关系”,确保让数智技术为农民群众注入更丰富和优质的精神滋养，增强实现中国式农业现代化的精神力量。

关键词：数智技术精神生活共同富裕科技创新文化数字化

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“跌倒”后是否还会“爬起来”:不同前因组态的创新失败对企业再创新行为的影响

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管理评论 2025年第1期37卷 87-99页

作者：孙冰张延丰田胜男哈尔滨工程大学经济管理学院哈尔滨150001

创新失败会对企业再创新行为产生何种影响?已有研究尚未得出一致结论,一个重要原因在于既有研究忽视了创新失败前因的复杂性和差异性。为此,综合运用模糊集定性比较分析(fsQCA)和倾向得分匹配(PSM)方法,以沪深两市A股的981家制造业上市... 详细信息

创新失败会对企业再创新行为产生何种影响?已有研究尚未得出一致结论,一个重要原因在于既有研究忽视了创新失败前因的复杂性和差异性。为此,综合运用模糊集定性比较分析(fsQCA)和倾向得分匹配(PSM)方法,以沪深两市A股的981家制造业上市企业为样本,在识别创新失败产生的多重前因组态路径的基础上,系统地考察了不同前因组态的创新失败对企业再创新行为的差异性影响。研究发现:第一,5种前因组态会引发创新失败:内部主因—知识缺失型失败、内部主因—治理缺失型失败、内部主因—认知和能力缺失型失败、外部主因—动力缺失型失败、内外共因—资金和能力缺失型失败;第二,引发创新失败的5种前因组态对企业再创新行为的影响存在差异:内部主因—知识缺失型失败、内部主因—治理缺失型失败、内外共因—资金和能力缺失型失败、外部主因—动力缺失型失败会导致企业减少再创新行为;内部主因—认知和能力缺失型失败会促使企业增加再创新行为。本文的研究旨在为企业管理者有效防范创新失败风险、为政府机构激发企业再创新提供经验参考。

关键词：前因组态创新失败企业再创新行为 fsQCA PSM

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长链非编码RNA核富集转录本1对瘢痕成纤维细胞增殖、凋亡和迁移的影响

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中国组织工程研究 2025年第2期29卷 347-354页

作者：张彦峰张慧敏何翔郑屿萍上海中医药大学附属曙光医院皮肤科上海市201203

背景:已有研究阐明核富集转录本1(nuclear enriched abundant transcript 1,NEAT1)下调抑制了瘢痕成纤维细胞的进展,但具体机制尚不完全清楚。目的:探讨长链非编码RNA NEAT1调节miR-136-5p/泛素特异性蛋白酶4(ubiquitin specific protease 4,USP4)轴对瘢痕成纤维细胞生物学行为的影响。方法:将瘢痕成纤维细胞分为5组:si-NC组、空白对照组、si-NEAT1组、si-NEAT1+miR-136-5p inhibitor组、si-NEAT1+inhibitor-NC组,qRT-PCR检测NEAT1、miR-136-5p表达;CCK-8法及EDU染色检测细胞增殖能力;流式细胞术检测细胞凋亡情况;划痕愈合实验检测细胞迁移情况;Western blot检测USP4、p27、Bax、基质金属蛋白酶9、α-平滑肌肌动蛋白、Ⅰ型胶原蛋白α1链蛋白表达;双荧光素酶实验检测NEAT1与miR-136-5p、miR-136-5p与USP4的关系。结果与结论:①与si-NC组比较,si-NEAT1组NEAT1表达、A450值、EDU阳性细胞百分比、划痕愈合率以及USP4、基质金属蛋白酶9、α-平滑肌肌动蛋白、Ⅰ型胶原蛋白α1链蛋白表达降低(P<0.05),miR-136-5p表达、细胞凋亡率及p27、Bax蛋白表达升高(P<0.05);②miR-136-5p inhibitor逆转了沉默NEAT1对瘢痕成纤维细胞生物学行为的影响;③miR-136-5p与NEAT1、miR-136-5p与USP4存在靶向调控关系。结果表明,沉默NEAT1可能通过调控miR-136-5p/USP4轴抑制瘢痕成纤维细胞的增殖和迁移,诱导其凋亡。

关键词：长链非编码RNA核富集转录本1 miR-136-5p 泛素特异性蛋白酶4 瘢痕成纤维细胞增殖

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Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

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涡轮导叶吸力面气膜冷却掺混损失全三维分析

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工程热物理学报 2025年第1期46卷 104-113页

作者：王晨枫李国庆白晓辉李年强张燕峰卢新根中国科学院工程热物理研究所北京100190 江苏大学流体机械工程技术研究中心镇江212013 中国科学院大学航空宇航学院北京100049 轻型涡轮动力全国重点实验室北京100190 中国科学技术大学工程科学学院合肥230027

针对现有气膜冷却掺混损失评估方法无法准确计算通道二次流影响区域内的主流冷气掺混损失的问题,本文建立了一种全三维掺混损失计算方法,基于HS1A涡轮导叶,在吸力面设置具有不同复合角的气膜孔以保证气膜冷却效率要求,进一步通过控制主... 详细信息

针对现有气膜冷却掺混损失评估方法无法准确计算通道二次流影响区域内的主流冷气掺混损失的问题,本文建立了一种全三维掺混损失计算方法,基于HS1A涡轮导叶,在吸力面设置具有不同复合角的气膜孔以保证气膜冷却效率要求,进一步通过控制主流与冷气参数分析了损失机理。该评估方法以掺混熵增作为损失评估依据对不同模型进行分析,结果表明:在吸力面气膜孔设置分区域复合角在提升气膜冷却效率的同时将增加掺混熵增。通过设置复合角可以减少二次流引起气膜偏转的损失以及气膜脱离产生的损失。

关键词：气膜冷却掺混损失冷却效率二次流

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Unsteady wakes-secondary flow interactions in a high-lift low-pressure turbine cascade

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Chinese Journal of Aeronautics 2020年第3期33卷 879-892页

作者： Xiao QU yanfeng zhang Xingen LU Junqiang ZHU Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China

Detailed experimental measurements were conducted to study the interactions between incoming wakes and endwall secondary flow in a high-lift Low-Pressure Turbine(LPT)*** of the measurements were conducted in both the presence and absence of incoming wakes,and numerical analysis was performed to elucidate the flow *** increasing Reynolds number,the influence of the incoming wakes on suppressing the secondary flow gradually increased owing to the greater influence of incoming wakes on reducing the negative incidence angle at higher Reynolds numbers,leading to a lower blade loading near the leading edge and suppression of the Pressure Side(PS)leg of the horseshoe ***,the effect of unsteady wakes on suppressing the profile losses gradually became weaker owing to the reduced size of the Suction Side(SS)separation bubble and increased mixing loss in the free-flow region at high Reynolds *** wakes clearly improved the aerodynamic performance of the low-pressure turbine cascade at low Reynolds numbers of 25,000 and 50,*** contrast,at the high Reynolds number of 100,000,the profile loss at the midspan and mass-averaged total losses downstream of the cascade were higher in the presence of wakes than in the absence of wakes,and the unsteady wakes exerted a negative influence on the aerodynamic performance of the LPT cascade.

关键词： Experimental study High-lift Incoming wakes Low-pressure turbine Secondary flow

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Unsteady experimental and numerical investigation of aerodynamic performance in ultra-high-lift LPT

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Chinese Journal of Aeronautics 2020年第5期33卷 1421-1432页

作者： Xiao QU yanfeng zhang Xingen LU Junqiang ZHU Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

Detailed experimental and numerical investigations were performed for an ultra-high-lift front-loaded low-pressure turbine cascade (Zw=1.58) with periodic *** interaction mechanisms between the incoming wakes and endwall secondary flow were carefully *** were produced by moving upstream rods,and flow field downstream of the cascade was measured using a seven-hole *** results revealed that incoming wakes influenced not only the boundary layer development of the blade suction surface but also the complex endwall secondary vortex *** the suction surface:Incoming wakes clearly suppressed the suction side separation bubble at a low Reynolds number of ***,the effects of different wake passing frequencies were not significantly different at Re=100000,and the profile losses under wake passing were even greater than in the absence of *** the end walls:Incoming wakes more strongly suppressed secondary flow at Re=100000 than at Re=25000,because the lowmomentum fluid inside the incoming wakes clearly increased the endwall cross-passage pressure gradient at Re=*** experimental results indicated that periodic wakes decreased the passage vortex and counter vortex core strength by 25% and 30%,respectively,at Re=*** results also demonstrated that endwall secondary vortices decreased significantly near the position of wakes passing.

关键词： Experimental investigation Low pressure turbine Periodic wake Secondary flow Ultra-High-lift

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Peak identification for ChIP-seq data with no controls

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Zoological Research 2012年第S3期33卷 121-128页

作者： yanfeng zhang Bing SU State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoologythe Chinese Academy of SciencesKunming 650223China

Chromatin immunoprecipitation followed by sequencing(ChIP-seq)is increasingly being used for genome-wide profiling of transcriptional regulation,as this technique enables dissection of the gene regulatory *** input as control,a variety of statistical methods have been proposed for identifying the enriched regions in the genome,i.e.,the transcriptional factor binding sites and chromatin ***,when there are no controls,whether peak calling is still reliable awaits systematic *** address this question,we used a Bayesian framework approach to show the effectiveness of peak calling without controls(PCWC).Using several different types of ChIP-seq data,we demonstrated the relatively high accuracy of PCWC with less than a 5%false discovery rate(FDR).Compared with previously published methods,e.g.,the model-based analysis of ChIP-seq(MACS),PCWC is reliable with lower ***,to interpret the biological significance of the called peaks,in combination with microarray gene expression data,gene ontology annotation and subsequent motif discovery,our results indicate PCWC possesses a high ***,using in silico data,only a small number of peaks were identified,suggesting the significantly low FDR for PCWC.

关键词： ChIP-seq Bayesian Peak calling Gene regulation

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Anisotropic monolayer of ReX_(2)on Au foils for exploring abnormal growth behavior and electronic properties

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Nano Research 2023年第3期16卷 4197-4210页

作者： Wenzhi Quan Shuangyuan Pan Fan Zhou yanfeng zhang Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China School of Materials Science and Engineering Peking UniversityBeijing 100871China

As an emerging class of semiconducting transition metal dichalcogenides(TMDCs),two-dimensional(2D)rhenium dichalcogenides(ReX_(2),X=S or Se)have recently aroused great research interest due to their unique anisotropic structure(1T′phase),and the related novel properties and ***,many efforts have been devoted to the controllable syntheses of high-quality monolayer or few-layer ReX_(2)flakes/films by chemical vapor deposition(CVD),wherein the metallic Au foil is found to be a unique substrate,due to the relatively strong interfacial coupling between monolayer ReX_(2)and *** the conductive nature of Au enables in situ characterizations of the as-grown ReX_(2)samples,which is essential for exploring the fundamental properties and internal growth ***,this review focuses on the recent progresses on the CVD syntheses and in situ characterizations of high-quality monolayer ReX_(2)flakes/films and their heterostructures with graphene on Au *** effects of Au foils on improving the crystal quality and inducing the growth of monolayer ReX_(2)single crystals are intensively *** crystallinity,domain morphology,atomic and electronic structures,as well as the growth behaviors of monolayer ReX_(2)flakes/films and graphene/ReX_(2)heterostructures on Au revealed by in situ characterization techniques are also *** contrasts,the growth behaviors of monolayer or few-layer ReX_(2)on insulating substrates are also ***,the potential applications of 2D ReX_(2)in new-generation electronic,optoelectronic devices,and energy-related fields are also ***,future research directions are also prospected for propelling the practical applications of 2D ReX_(2)materials in more versatile fields.

关键词： rhenium dichalcogenides(ReX_(2)) Au chemical vapor deposition scanning tunneling microscopy/spectroscopy growth behavior electronic properties

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