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Nonlinear uncertainty impact of geometric variations on aerodynamic performance of low-pressure turbine blades with ultra-high loading under extreme operational conditions

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Chinese Journal of Aeronautics 2024年第5期37卷 281-300页

作者： Xiaojing wang Zhengping ZOU Chao FU pengcheng DU School of Energy and Power Engineering Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Uncertainty impact of random geometric variations on the aerodynamic performance of low-pressure turbine blades is considerable,which is further amplified by the current ultra-high-lift design trend for weight ***,this uncertainty impact on ultra-highly loaded blades under extreme operational conditions near the margins with potential large-scale open separation is focused on in this *** is demonstrated that this impact is significant,unfavourable,and nonlinear,which is clearly severer under extreme *** addition to the overall attenuation and notable scattering of specific performance,the operational margins with open separation are also notably scattered with great risk of significant *** scattering and nonlinearity are dominated by the variations in leading-edge *** thinning of leading edge triggers local transition,enhancing downstream friction and reducing resistance to open separation,which is further exacerbated by operational ***,the opposite thickening yields less benefit,implying *** unfavourable impact highlights the need for robust aerodynamic design,where both a safer operational condition and a more robust blade are indispensable,i.e.,a compromise among performance,weight,and *** the necessary limitation of loading levels,a mid-loaded design is recommended to reduce adverse pressure gradients in both the leading edge and rear region of the suction side,which helps to decrease the susceptibility of the transition and open separation to random *** improvements can also be achieved by appropriately thickening the leading edge.

关键词： Ultra-highly loaded turbine blade Geometric variations Uncertainty analysis Operational margins Robust aerodynamic design Nonlinearity

马铃薯种质资源抗黑痣病鉴定及SSR聚类分析

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黑龙江八一农垦大学学报 2024年第5期36卷 15-23页

作者：王紫雯金光辉王腾王鹏程高睿吴国强黑龙江八一农垦大学农学院大庆163319

马铃薯黑痣病已成为影响马铃薯产量和商品价值的重要土传病害。为丰富马铃薯抗黑痣病种质资源,提高抗黑痣病育种工作效率,研究通过54份马铃薯种质资源地下茎与匍匐茎黑痣病抗性评价,共筛选出7份中抗资源,分别为克17-33-270、龙18-124-8... 详细信息

马铃薯黑痣病已成为影响马铃薯产量和商品价值的重要土传病害。为丰富马铃薯抗黑痣病种质资源,提高抗黑痣病育种工作效率,研究通过54份马铃薯种质资源地下茎与匍匐茎黑痣病抗性评价,共筛选出7份中抗资源,分别为克17-33-270、龙18-124-8、龙18-7-100、ND11-7-22、克18-134-5、克17-115-1、克17-6-9。研究利用8对SSR适宜引物对7份抗性材料DNA进行PCR扩增,获得SSR多态性条带42条,多态性比率89.36%,遗传相似性系数在0.444 4~0.833 3之间,以相似性系数0.62为基准,可将7份抗性材料分为3类,其中克18-134-5和克17-115-1为一类;龙18-124-8和龙18-7-100为一类;克17-33-270、ND11-7-22和克17-6-9为一类。

关键词：马铃薯(Solanum tuberosum L.) 种质资源抗性鉴定黑痣病 SSR分子标记

Seasonal increase of nest height of the Silver-throated Tit(Aegithalos glaucogularis): can it reduce predation risk?

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Avian Research 2018年第4期9卷 306-313页

作者： Haohui Guan Ye Wen pengcheng wang Lei Lv Jiliang Xu Jianqiang Li School of Nature Conservation Beijing Forestry University Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering College of Life Sciences Beijing Normal University School of Life Sciences Sun Yat-sen University

Background: Nest predation is usually the main cause of bird nest failure. ‘Predation avoidance hypothesis' of nestsite selection predicts that birds should prefer nest-sites with higher nesting success. We investigated the relationship between nest height and nest fate in Silver-throated Tits(Aegithalos glaucogularis) and asked whether the seasonal change of nest height was adaptive by simultaneously analyzing the seasonal variation of predation rates of the ***: We monitored nests of the Silver-throated Tit across seven breeding seasons in the Dongzhai National Nature Reserve in Henan Province of China. We compared the difference of nesting success among nests of different heights and analyzed the effect of nesting date on nest height and nest predation ***: The overall nesting success rate was 24.1%(n ds and mammals, followed by snakes(9.11%= 623). Among the failed nests(n). The average height of successf= 472), 59.75% were predated by birul nests was significantly lower than that of predated nests. As the season progresses, the height of the nests increased significantly, companied by the decrease in nesting success. Daily survival rate of the nests also decreased with the progression of the season, regardless of breeding ***: Our findings suggest that nest height is an important factor influencing the nesting success of Silverthroated Tits. However, the seasonal increase of nest height appears inconsistent to the ‘predation avoidance hypothesis', because it is associated with higher predation rates. The reason for this maladaptive behavior remains to be explored in future studies.

关键词： Nesting success Nest height Daily survival rate Seasonal variation Aegithalos glaucogularis

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氢燃料电池发动机多种限功率工况的应用试验

汽车电器 2024年第9期 14-15,19页

作者：张鹏韩福强汪鹏程赵玄潍柴动力股份有限公司山东潍坊261061

氢燃料电池发动机主要由空气子系统、氢气子系统、冷却子系统等组成。各子系统均有各自不同的性能指标,当各自的性能指标均满足当前工况的要求时,燃料电池发动机才可以正常运行。当某个指标达不到当前要求但车辆仍然需要运行时,就需要... 详细信息

氢燃料电池发动机主要由空气子系统、氢气子系统、冷却子系统等组成。各子系统均有各自不同的性能指标,当各自的性能指标均满足当前工况的要求时,燃料电池发动机才可以正常运行。当某个指标达不到当前要求但车辆仍然需要运行时,就需要进入限功率工况,保证车辆的基本功能正常运行。文章主要基于空气子系统、氢气子系统、冷却子系统等不同性能指标进行相应的限功率工况的应用测试。

关键词：氢燃料电池发动机限功率工况测试发动机性能

维普期刊数据库博看期刊

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短路冲击下的船用柴油机瞬态扭振特性分析

中国舰船研究 2024年第S1期19卷 93-100页

作者：徐聪聪梁刚陶杰焦亚飞陈晋元王鹏程邓梦灿上海船用柴油机研究所上海201108 哈尔滨工程大学动力与能源工程学院黑龙江哈尔滨150001

[目的]为提出船用柴油发电机组的轴系扭振参数优化方案,需分析其在短路冲击下的瞬态扭转振动特性。[方法]采用Newmark法,以某型20 V柴油发电机组的短路冲击工况为例,对比不同轴系参数对轴系瞬态扭振特性的影响规律,进而基于参数优化结... 详细信息

[目的]为提出船用柴油发电机组的轴系扭振参数优化方案,需分析其在短路冲击下的瞬态扭转振动特性。[方法]采用Newmark法,以某型20 V柴油发电机组的短路冲击工况为例,对比不同轴系参数对轴系瞬态扭振特性的影响规律,进而基于参数优化结果来确定新的机组减振器刚度与联轴器刚度选配方案。[结果]研究结果表明:发生短路冲击时,轴系扭振特性将显著恶化;经优化之后(将扭振减振器刚度、联轴器刚度分别优选为原始值的0.9和0.70倍),短路冲击工况下的电机轴瞬时最大附加应力、联轴器瞬时最大扭矩、曲轴各轴段瞬时最大应力分别降低了13.43%,10.51%,5.29%。[结论]该参数优化方案可以有效降低轴系的瞬态扭振水平,研究成果可为柴油发电机组的减振降噪设计提供参考。

关键词：船用柴油机轴系扭振短路冲击参数优化

Functional and phylogenetic structures of pheasants in China

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Avian Research 2022年第3期13卷 229-238页

作者： Hongyan Yao pengcheng wang Nan wang Philip J.K.McGowan Xingfeng Si Jianqiang Li Jiliang Xu School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal University1 Wenyuan RoadNanjing210023China School of Natural and Environmental Sciences Newcastle UniversityNewcastleNE17RUUK Zhejiang Tiantong Forest Ecosystem National Observation and Research Station School of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China

Biodiversity has been subjected to increasing anthropogenic *** is critical to understand the different processes that govern community assembly and species coexistence under biogeographic processes and anthropogenic ***(Aves:Phasianidae)are highly threatened birds and China supports the richest pheasant species *** the spatial patterns and underlying factors associated with multidimensional biodiversity of species richness(SR),functional diversity(FD),and phylogenetic diversity(PD)of pheasants in China is helpful to understand not only the processes that govern pheasant community assembly and species coexistence,but also pheasant biodiversity *** used a total of 45 pheasant species in China and analyzed the SR,FD,PD,and functional and phylogenetic structures by integrating species distribution maps,functional traits and phylogenies based on 50 km×50 km grid *** further used simultaneous autoregressive(SAR)models to explore the factors that determined these *** southern Qinghai-Tibetan Plateau(QTP),Hengduan Mountains,southwestern Mountains,the east of the Qilian Mountains,the Qinling,southern China displayed higher SR,FD,and PD,which were determined by elevation,habitat heterogeneity,temperature seasonality,and vegetation *** primarily determined the functional and phylogenetic structures of the pheasant *** in the highlands were marked by functional and phylogenetic clustering,particularly in the QTP,whereas the lowlands in eastern China comprised community *** pheasant assemblages were composed of young *** of functional and phylogenetic structures and richness-controlled functional and phylogenetic diversity differed between regions,suggesting that phylogenetic structures are not a good proxy for identifying functional *** revealed the significant role of elevation in pheasant community assemblages in *** inter

关键词： China Community assembly Environmental filtering Functional traits Pheasants Phylogeny Species richness

奥氏体转变温度以上变形时应变速率对低碳钢动态软化行为的影响

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热加工工艺 2024年第11期53卷 82-85,90页

作者：刘永超王少强王鹏程桑学科丁宁刘珑许慧霞郭卫民金雷科技股份公司山东济南271105 山东省材料失效分析与安全评估工程技术中心山东省分析测试中心齐鲁工业大学(山东省科学院) 山东济南250014

利用Gleeble-1500热模拟试验机,将一低碳微合金钢在Ac3温度以上(950℃)进行了4种不同的应变速率(10、7、3、1 s^(-1))的压缩变形,然后淬火处理。对高温变形的应力应变曲线用双微分法进行变换,发现材料变形过程中主要有两种软化机制,分... 详细信息

利用Gleeble-1500热模拟试验机,将一低碳微合金钢在Ac3温度以上(950℃)进行了4种不同的应变速率(10、7、3、1 s^(-1))的压缩变形,然后淬火处理。对高温变形的应力应变曲线用双微分法进行变换,发现材料变形过程中主要有两种软化机制,分别为动态相变和动态再结晶,随变形速率的增加,材料发生软化的两个临界应力呈线性升高的趋势;两个临界应变则随应变速率变化不大。用金相显微镜观察观察了材料淬火后的金相组织,发现材料内的Widmanstätten铁素体板条宽度随应变速率的增加而逐渐变细,多边形铁素体的数目随应变速率的增加而增加;Widmanstätten铁素体板条一般为平行或垂直关系,而垂直关系的Widmanstätten铁素体板条并不呈现严格的直角,而是偏离一定的角度。

关键词：低碳钢动态再结晶动态相变双微分法应变速率

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“造价BIM”模式应用研究

土木建筑工程信息技术 2024年第1期16卷 104-108页

作者：王鹏程吴天晴闫继科李天清王雪新一(苏州)数字科技有限公司苏州215000 苏州新一造价师价格事务所有限公司苏州215000

本研究对造价咨询企业的发展需求进行实地调研,并基于调研成果对传统造价行业存在的痛点问题进行梳理和总结。根据企业实际需求提出通过对设计BIM模型造价深化,实现BIM模型全流程应用的“造价BIM”发展模式,对“造价BIM”模式落地应用... 详细信息

本研究对造价咨询企业的发展需求进行实地调研,并基于调研成果对传统造价行业存在的痛点问题进行梳理和总结。根据企业实际需求提出通过对设计BIM模型造价深化,实现BIM模型全流程应用的“造价BIM”发展模式,对“造价BIM”模式落地应用存在的难点问题进行深入分析,并通过实际案例阐述了“造价BIM”模式对推动咨询企业实现BIM模型全流程应用的可行性,以及实现“一个模型用到底”的价值意义。

关键词： BIM 工程算量模型工程造价信息共享协同管理

Inter-glacial isolation caused divergence of cold-adapted species:the case of the snow partridge

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Current Zoology 2022年第4期68卷 489-498页

作者： Hongyan Yao Yanan Zhang Zhen wang Gaoming Liu Quan Ran Zhengwang Zhang Keji Guo Ailin Yang Nan wang pengcheng wang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing100083China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China Hangzhou Xi’ao Environmental Science Technique Company Limited Zhejiang 310011China Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Yancheng Wetland and World Natural Heritage Conservation and Management Center Jiangsu 224000China Central South Inventory and Planning Institute of National Forestry and Grassland Administration Changsha 410014China Chinese Institute for Brain Research Beijing 102206China

Deciphering the role of climatic oscillations in species divergence helps us understand the mechanisms that shape global *** coldadapted species may have expanded their distribution with the development of glaciers during glacial *** the retreat of glaciers,these species were discontinuously distributed in the high-altitude mountains and isolated by geographical ***,the study that focuses on the speciation process of cold-adapted species is *** fill this gap,we combined population genetic data and ecological niche models(ENMs)to explore divergence process of snow partridge(Lerwa lerwa).Lerwa lerwa is a cold-adapted bird that is distributed from 4,000 to 5,500 *** found 2 genetic populations within ***,and they diverged from each other at about 0.40–0.44 million years ago(inter-glacial period after Zhongliangan glaciation).The ENMs suggested that *** expanded to the low elevations of the Himalayas and Hengduan mountains during glacial period,whereas it contracted to the high elevations,southern of Himalayas,and Hengduan mountains during inter-glacial *** population size trajectory also suggested that *** expanded its population size during the glacial *** with our expectation,the results support that inter-glacial isolation contributed to the divergence of cold-adapted *** on Qinghai-Tibetan *** study deepens our understanding of how climatic oscillations have driven divergence process of cold-adapted Phasianidae species distributed on mountains.

关键词： climate fluctuations divergence Qinghai-Tibetan Plateau Quaternary snow partridge