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大型往复式压缩机气阀故障诊断机理研究

武汉理工大学学报 2024年第6期46卷 120-128页

作者：余永华徐德峰王康宋朝琪潘耀宇胡磊尧阳烽武汉理工大学船海与能源动力工程学院武汉430063 船舶动力工程技术交通运输行业重点实验室武汉430063 中国空气动力研究与发展中心绵阳621000

气阀作为大型往复压缩机的关键部件,其故障率排在压缩机故障首位,开展气阀故障机理研究对其故障判据的确定具有指导意义。作者以某型往复式压缩机为研究对象,利用Simulink建立零维数值仿真模型,计算了正常状态下的缸内气体压力的动态过... 详细信息

气阀作为大型往复压缩机的关键部件,其故障率排在压缩机故障首位,开展气阀故障机理研究对其故障判据的确定具有指导意义。作者以某型往复式压缩机为研究对象,利用Simulink建立零维数值仿真模型,计算了正常状态下的缸内气体压力的动态过程,在压缩机试验台架上进行了缸压测量,验证了仿真模型的有效性,在此基础上进行了气阀泄漏、弹簧失效等故障仿真,从理论上分析了不同故障对气阀开启角度、p-V图面积、多变指数信号的影响规律,研究表明:排气阀故障越严重,进气阀开启角度越延后,排气阀开启角度越提前,p-V图面积越大,压缩膨胀梯度比越大;进气阀故障时反之,可为往复式压缩机气阀实时监测和故障诊断提供参考指导。

关键词：往复式压缩机气阀故障仿真建模缸压测量 p-V图

Geochemical Characteristics of Eolian Deposits on the Eastern Margin of the Tibetan Plateau and Implications for Provenance

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 963-973页

作者： qi Lin qiAO Yan-song School of Earth Sciences and Resources China University of Geosciences Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Neotectonic Movement and Geohazard

Eolian dust deposition is intimately related to atmospheric circulation and environmental setting of the source region,and therefore is an invaluable tool for studying the evolutionary history of atmospheric circulation patterns and paleoclimatic *** the provenance of any eolian deposit is crucial not only for reconstructing the paleoenvironmental history of the dust source region,but also for understanding the paleoclimatic significance of various *** and paleosol samples from the Garze region on the eastern margin of the Tibetan Plateau （TP） were analyzed for their elemental （major and trace elements） and isotopic （Sm-Nd） geochemistry and compared with those of Northern Chinese （NC） loess formed at the same *** results show that the geochemical compositions of the Garze loess and paleosol samples are similar to those eolian deposits on the Chinese Loess Plateau （CLP）,and also resemble the average *** indicates that the eolian deposits on the eastern margin of the TP were derived from well-mixed sedimentary protoliths that had undergone numerous upper crustal recycling processes,just as with the CLP loess ***,compared with NC loess,the Garze samples have higher ∑REE,Li,Rb,Zr,Cs,Hf and Bi concentrations,higher TiO2/Al2O3,Hf/Nb,La/Nb,Th/Nb and lower K2O/TiO2,Zr/Hf,Ba/Rb *** the Sm-Nd isotopic geochemistry,εNd（0） and 147Sm/144Nd values of Garze loess and paleosol samples are clearly lower than the NC *** higher Bi,Zr and Hf concentrations are relevant to the widely distributed acid-magmatic rocks in this region,whereas the higher contents of Li,Cs,Rb are attributed to the high background values of the *** geochemical characteristics of the Garze loess and paleosol samples further prove that the local glacial and other Quaternary detrital sediments are predominantly the contributors for the eolian deposits on the eastern margin of the *** element concentrations and their ratios in the Garze loess and

关键词： Quaternary eolian sedimentology geochemistry provenance Tibetan paleoclimate,Sichuan province

A Survey on Collaborative DNN Inference for Edge Intelligence

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Machine Intelligence Research 2023年第3期20卷 370-395页

作者： Wei-qing Ren Yu-Ben Qu chao Dong Yu-qian Jing Hao Sun qi-Hui Wu song Guo College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing211100China Department of Computing Hong Kong Polytechnic UniversityHong Kong999077China

With the vigorous development of artificial intelligence(AI),intelligence applications based on deep neural networks(DNNs)have changed people’s lifestyles and production ***,the large amount of computation and data generated from the network edge becomes the major bottleneck,and the traditional cloud-based computing mode has been unable to meet the requirements of realtime processing *** solve the above problems,by embedding AI model training and inference capabilities into the network edge,edge intelligence(EI)becomes a cutting-edge direction in the field of ***,collaborative DNN inference among the cloud,edge,and end devices provides a promising way to boost ***,at present,EI oriented collaborative DNN inference is still in its early stage,lacking systematic classification and discussion of existing research *** by it,we have comprehensively investigated recent studies on EI-oriented collaborative DNN *** this paper,we first review the background and motivation of ***,we classify four typical collaborative DNN inference paradigms for EI,and analyse their characteristics and key ***,we summarize the current challenges of collaborative DNN inference,discuss future development trends and provide future research directions.

关键词： Artificial intelligence(AI) edge intelligence(EI) distributed computing deep neural network(DNN) collaborative inference

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Weakly magnetic field-assisted synthesis of magnetite nano-particles in oxidative co-precipitation

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Particuology 2009年第5期7卷 363-367页

作者： Dawei Hu Yanmin Wang qi song College of Materials Science and Engineering South China University of Technology 510640 Guangzhou China Key Laboratory of Special Functional Materials under Ministry of Education 510640 Guangzhou China

This paper presents experimental results on weakly magnetic field-assisted synthesis of magnetite （Fe3O4） nano-particles in an oxidative co-precipitation method, in comparison to the case without magnetic induction. The XRD results show that a weakly magnetic induction below 220 Gs could accelerate the phase transformation from goethite （α-FeOOH） to magnetite （Fe3O4）, and affect the crystal structure, the particle size/morphology and magnetic response of the magnetite nano-particles synthesized. In addition, a higher concentration of the FeCl2 solution in the synthesis reaction led to finer particles, both with and without magnetic induction.

关键词： Magnetic field Oxidative co-precipitation Nano-particle Magnetite Morphology

A Robust Noninvasive Approach to Study Gut Microbiota Structure of Amphibian Tadpoles by Feces

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Asian Herpetological Research 2018年第1期9卷 1-12页

作者： Xiaowei song Jinghan song Honghong song qi ZENG Keke SHI College of Life Sciences Xinyang Normal University Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains Xinyang Normal University

The 16S rDNA amplicon high-throughput sequencing technique provides a robust and inexpensive approach to detect the gut microbiota of amphibians. Since different experimental protocols generate technical biases in drawing the gut microbiota profiles, the integrative analysis of gut microbiota produced by different studies must be performed with circumspection. In this study, we compared the efficacy of two DNA extraction methods （i.e., a phenol-chloroform method and TIANamp Stool DNA Kit） in describing intestinal and fecal bacterial communities of transplanted Asiatic toad （Bufo gargarizans） tadpoles. In terms of the DNA extraction quality （i.e., DNA purity and yield rate） and the consistency in between fecal and intestinal microbiota structures （i.e., a and 13 diversity indices）, the phenol-chloroform method was more robust than this commercial stool kit in profiling gut microbiota of tadpoles with feces.

关键词： Bufo gargarizans DNA extraction intestinal microflora Phenol-chloroform 16S rDNA

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基于PLC的热处理设备控制系统设计

机械工程师 2013年第12期 94-95页

作者：王希凤徐鹿眉乔爽葛洪军宋起超孟大伟张纪勇黑龙江工程学院电气与信息工程学院哈尔滨150050 哈尔滨理工大学电气与电子工程学院哈尔滨150080

应用可编程序控制器进行热处理设备控制系统的设计,组成现场总线控制系统,实现热处理设备的正常运行。控制热处理设备炉门、机械手、水泵、真空泵和气压阀等各部件的运动,并对电阻丝加热进行控制。应用温度、压力、真空度等传感器进行... 详细信息

应用可编程序控制器进行热处理设备控制系统的设计,组成现场总线控制系统,实现热处理设备的正常运行。控制热处理设备炉门、机械手、水泵、真空泵和气压阀等各部件的运动,并对电阻丝加热进行控制。应用温度、压力、真空度等传感器进行炉体环境指标检测,能够显示数据和到限报警。

关键词：可编程序控制器(PLC) 热处理设备现场总线控制系统(FCS)

Effects of residual plastic film on crop yield and soil fertility in a dryland farming system

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Journal of Integrative Agriculture 2023年第12期22卷 3783-3791页

作者： WANG Dong XI Yue SHI Xiao-yan GUO chao-li ZHONG Yu-jie song chao GUAN Yu HUANG Lu YANG qi-feng LI Feng-min College of Ecology Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Agriculture Nanjing Agricultural UniversityNanjing 210095P.R.China State Key Laboratory of Grassland Agro-Ecosystems Institute of Arid Agroecology/College of EcologyLanzhou UniversityLanzhou 730000P.R.China Teaching Affairs Office Jilin Normal UniversitySiping 136099P.R.China Department of Resources and Environmental Science College of Agriculture/The Key Laboratory of Oasis Eco-Agriculture of the Xinjiang Production and Construction CorpsShihezi UniversityShihezi 832000P.R.China Institute of Microbiology Chinese Academy of SciencesBeijing 100101P.R.China Gansu Provincial Department of Agriculture and Rural Affairs Lanzhou 730000P.R.China

Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid ***,the presence of residual film in farmland soil has also drawn much *** this study,three experiments were *** first two experimental designs included 0,450,1350,and 2700 kg ha^(-1) of residual film pieces of approximately 5 cm side length added to field soil(0-20 cm soil depth)for seven years and added to pots for four *** the third experiment,1350 kg ha^(-1)of the residual film with different side lengths(2-5,5-10,10-15,and 15-20 cm)was added to field soil for six years to explore the effect of residual film fragment size on soil nutrients,soil microorganisms,crop growth and *** residual film had little effect on the soil moisture at a field depth of 0-2(or 0-1.8)*** were no significant effects on organic carbon,total nitrogen,inorganic nitrogen,total phosphorus or available phosphorus in the 0-20 cm soil *** presence of residual film decreased the richness and diversity of the bacterial community of the surface soil of the residual film,but it had no significant effect on the microbial community of the non-surface *** emergence rates of wheat and lentils occasionally decreased significantly with different amounts of residue fragments added to the *** 450-2700 kg ha^(-1),the residual film reduced the plant height and stem diameter of maize and significantly reduced the shoot biomass of harvested maize by 11-19%.The average yields of maize and potato over the seven years decreased,but there were almost no significant statistical differences among the *** results provide important data for a comprehensive scientific understanding of the effects of residual film on soil and crops in dryland farming systems.

关键词： residual film soil nutrients microbial community crop yield

Synthesis of 2,4-Diarylcyclooctenopyridines with One-pot Four-component Reactions

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Chemical Research in Chinese Universities 2009年第3期25卷 338-342页

作者： WANG qi-fang YAN chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

An efficient one-pot four-component reaction has been developed for the synthesis of 2,4-diarylcyclooctenopyridines, in moderate yields. This route is an effective modified two-step synthesis of Krohnke pyridine and involves a four-component tandem reaction of pyridinium bromide with aromatic aldehydes and cyclooctanone in a system of NHaOAc/HOAc under microwave irradiation.

关键词： Pyridine Cycloalkenopyridine Multicomponent reaction Microwave irradiation