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Experimental Study of Cavitation Phenomenon in a Centrifugal Blood Pump Induced by the Failure of Inlet Cannula

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 165-170页

作者： LIN Zhe RUAN Xiaodong ZOU jun fu Xin The State Key Lab of Fluid Power Transmission and Control Zhejiang University

Cavitation of centrifugal blood pump is a serious problem accompany with the blocking failure of short inlet cannula. However, hardly any work has been seen in published literature on this complex cavitation phenomenon caused by the coupling effect of inlet cannula blocking and pumps suction. Even for cavitation studies on ordinary centrifugal pumps, similar researches on this issue are rare. In this paper, the roles of throttling, rotation speed and fluid viscosity on bubble inception and intensity in a centrifugal blood pump are studied, on the basis of experimental observations. An adjustable throttle valve installed just upstream blood pump inlet is used to simulate the throttling effect of the narrowed inlet cannula. The rotation speed is adjusted from 2 600 r/rain to 3 200 r/min. Glycerin water solutions are used to investigate the influences of kinetic viscosity. Bubbles are recorded with a high-speed video camera. Direct observation shows that different from cavitation in industrial centrifugal pumps, gas nuclei appears at the nearby of vane leading edges while throttling is light, then moves upstream to the joint position of inlet pipe and pump with the closing of the valve. It＇s found that the critical inlet pressure, obtained when bubbles are first observed, decreases linearly with viscosity and the slope is independent with rotation speeds; the critical inlet pressure and the inlet extreme pressure which is obtained when the throttle valve is nearly closed, fall linearly with rotation speed respectively and the relative pressure between them is independent with rotation speed and fluid viscosity. This paper studies experimentally on cavitation in centrifugal blood pump that caused by the failure of assembled short inlet cannula, which mav beneficial the desima of centrifugal blood Dumo with inlet cannula.

关键词： centrifugal blood pump cavitation viscosity cannula diameter rotation speed

Multi-view ladar data registration in obscure environment

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Journal of Systems Engineering and Electronics 2013年第4期24卷 606-616页

作者： Mingbo Zhao jun He Wei Qiu Qiang fu Science and Technology Automatic Target Recognition Laboratory National University of Defense Technology Unit 93246 of the PLA

Multi-view laser radar （ladar） data registration in obscure environments is an important research field of obscured target detection from air to ground. There are few overlap regions of the observational data in different views because of the occluder, so the multi-view data registration is rather difficult. Through indepth analyses of the typical methods and problems, it is obtained that the sequence registration is more appropriate, but needs to improve the registration accuracy. On this basis, a multi-view data registration algorithm based on aggregating the adjacent frames, which are already registered, is proposed. It increases the overlap region between the pending registration frames by aggregation and further improves the registration accuracy. The experiment results show that the proposed algorithm can effectively register the multi-view ladar data in the obscure environment, and it also has a greater robustness and a higher registration accuracy compared with the sequence registration under the condition of equivalent operating efficiency.

关键词： laser radar (ladar) multi-view data registration iterative closest point obscured target point cloud data.

Range anomaly suppression based on neighborhood pixels detection in ladar range images

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Journal of Systems Engineering and Electronics 2013年第1期24卷 68-75页

作者： Mingbo Zhao jun He Zaiqi Lu Qiang fu Automatic Target Recognition Key Laboratory School of Electronic Science and EngineeringNational University of Defense Technology No.93246 Troop of the PLA

Research on the range anomaly suppression algorithm in laser radar （ladar） range images is significant in the application and development of ladar. But most of existing algorithms cannot protect the edge and linear target well while suppressing the range anomaly. Aiming at this problem, the differences among the edge, linear target, and range anomaly are analyzed and a novel algo- rithm based on neighborhood pixels detection is proposed. Firstly, the range differences between current pixel and its neighborhood pixels are calculated. Then, the number of neighborhood pixels is detected by the range difference threshold. Finally, whether the current pixel is a range anomaly is distinguished by the neighbor- hood pixel number threshold. Experimental results show that the new algorithm not only has a better range anomaly suppression performance and higher efficiency, but also protects the edge and linear target preferably compared with other algorithms.

关键词： image processing range anomaly suppression neigh-borhood p xe s detection linear target laser radar (ladar).

GraS is critical for chloroplast development and affects yield in rice

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Journal of Integrative Agriculture 2020年第11期19卷 2603-2615页

作者： DU Zhi-xuan HAO Hui-ying HE Jin-peng WANG Jian-ping HUANG zhou XU Jie fu Hai-hui fu jun-ru HE Hao-hua Key Laboratory of Crop Physiology Ecology and Genetic BreedingMinistry of Education/Collaboration Center for Double-season Rice Modernization ProductionJiangxi Agricultural University/Research Center of Super Rice Engineering and TechnologyJiangxi ProvinceNanchang 330045P.R.China

Leaf color has been considered an important agronomic trait in rice(Oryza sativa L.)for a long *** changes in leaf color affect the yield of *** this study,a green-revertible albino(graS)mutant was isolated from a 60Co-gamma-irradiated mutant pool of indica cultivar Guangzhan *** fine mapping indicated that graS mutant was mapped to chromosome 1,and was located in a confined region between markers ab134 and InDel 8 with genetic distances of 0.11 and 0.06 cM,*** on the annotation results,four open reading frames(ORFs)were predicted in this *** analysis revealed that LOC_Os01g55974 had a 2-bp nucleotide insertion(AA)in the coding region that led to premature termination at the 324th *** analysis and expression analysis of related genes indicated that LOC_Os01g55974 is the candidate gene of *** studied the genome and protein sequences of LOC_Os01g55974,and the data showed that GraS contains a deoxycytidine deaminase domain,which was expressed ubiquitously in all *** investigation indicated that GraS plays an essential role in the regulation of chloroplast biosynthesis,photosynthetic capacity and ***,leaf color mutant can be used as an effective marker for the purity of breeding and hybridization.

关键词： GraS bioinformatics candidate gene chlorophyll leaf color rice

Sound Velocities in Porous Iron Shocked to 177GPa and the Implications for Shock Melting

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Chinese Physics Letters 2001年第12期18卷 1632-1634页

作者： LI Xi-jun zhou Xian-Ming WANG Fan-Hou LIU fu-Sheng GONG Zi-Zheng JING fu-Qian fundamental Research Center Institute of Electronic EngineeringP.O.Box 919-510Mianyang 621900 Institute of Fluid Physics P.O.Box 919-102Mianyang 621900 Institute of High Pressure Physics Southwest Jiaotong UniversityChengdu 610036

Sound velocities in shock-loaded solids are not only important to determine bulk moduli of solids at high pressures, but are also crucial to inform the shock melting of solids upon loading. In this letter, we first report on shock melting of porous solids at high pressures by measuring sound velocities in the porous iron of average density 6.90 g/cm^(3) in the pressure range of 110-180 GPa. The measured sound velocity softens at pressures from 122 to 156 Gpa, which may be attributed to shock melting of the porous iron.

关键词： solids shock porous

A STUDY ON UNSTEADY SEEPAGE FLOW THROUGH DAM

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Journal of Hydrodynamics 2009年第4期21卷 499-504页

作者： fu jun-feng JIN Sheng State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A numerical model is proposed to simulate the unsteady seepage flow through dam, with both saturation and water head as variables to describe the seepage domain. Experiments of seepage flow through dam with unsteady conditions were conducted in laboratory to verify the reliability and the accuracy of the numerical model. The performance of the model is also assessed by comparing with analytical solutions. The examples show that the accuracy and the reliability of the model are adequate to handle seepage flow problems with complex conditions. It is also demonstrated that the method of determining the seepage surface through the saturation description is natural, logical and practical in actual applications. The method provides a relatively simple computing scheme, as compared with traditional methods.

关键词： saturation unsteady seepage saturated and unsaturated seepage finite element method

Variations in the Biomechanics of 16 Palmar Hand Regions Related to Tomato Picking

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Journal of Bionic Engineering 2023年第1期20卷 278-290页

作者： Xue An Zhiguo Li jun fu Tobi Fadiji Sheng Zhang College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingXianyang712100China The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130012China Postharvest Research Laboratory Department of Botany and Plant BiotechnologyUniversity of JohannesburgJohannesburg2006South Africa Dynax Corporation 1-12-710FFuchuchoFuchushiTokyo183-0055Japan

The aim of this study is to systematically reveal the differences in the biomechanics of 16 hand regions related to bionic picking of *** biomechanical properties(peak loading force,elastic coefficient,maximum percentage deformation and interaction contact mechanics between human hand and tomato fruit)of each hand region were experimentally measured and covariance *** results revealed that there were significant variations in the assessed biomechanical properties between the 16 hand regions(p<0.05).The maximum pain force threshold(peak loading force in I2 region)was 5.11 times higher than the minimum pain force threshold(in Th1 region).It was found that each hand region in its normal direction can elastically deform by at least 15.30%.The elastic coefficient of the 16 hand regions ranged from 0.22 to 2.29 N mm−*** interaction contact force acting on the fruit surface was affected by the selected human factors and fruit *** obtained covariance models can quantitatively predict all of the above biomechanical properties of 16 hand *** findings were closely related to hand grasping performance during tomato picking,such as soft contact,surface interaction,stable and dexterous grasping,provided a foundation for developing a high-performance tomato-picking bionic robotic hand.

关键词： Human hand.Bionic grasping Elastic deformation Tomato picking Robotic hand

Surveillance of viral contamination of invasive medical instruments in dentistry

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第9期7卷 745-748页

作者： zhou Lin-fu ZHU Hai-hong LIN jun HU Min-jun CHEN Feng CHEN Zhi Experimental Center of Molecular and Cellular Biology School of Medicine Zhejiang University Hangzhou 310006. China Institute of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Stomatology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To investigate the viral contamination of invasive medical instruments in dentistry and to provide health administrative institutions with surveillance data. Methods: Sterilized samples were randomly collected from the department of dentistry to detect HBV-DNA, HCV-RNA, HIV-RNA and HBsAg. Results: Of the invasive medical instruments that were ster- ilized with 2% glutaraldehyde, one of the samples was positive for HBV-DNA, and another sample was positive for HBsAg. Conclusion: Though massive virus contamination of invasive medical instruments in dentistry has been reduced to a low level, the occurrence of contamination still remains.

关键词： Glutaraldehyde Viral contamination Invasive

Multiphase flow physics of room temperature liquid metals and its applications

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Science China(Technological Sciences) 2023年第6期66卷 1483-1510页

作者： QIAO MengWen XING ZeRong fu jun-Heng LIU Jing CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryBeijing 100190China School of future Technology University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Cryo-Biomedical Engineering Beijing 100190China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYa’an 625014China Department of Biomedical Engineering School of MedicineTsinghua UniversityBeijing 100084China

Multiphase flow existing everywhere in the motion evolution of nature,industrial processes,and daily life,has been an interdisciplinary cutting-edge frontier covering rather diverse *** multiphase flow of high melting metals typically involves gas/vapor-liquid two-phase fluidics which usually requests intense energy processes and therefore limits their applications to a large *** from this,the newly emerging room-temperature liquid metals(RTLMs)with fascinating metallic fluidic properties and multifunctional behaviors,not only well resolve the existing challenges facing conventional technologies,but also open up a series of new scientific and engineering *** the conceptual introduction of multiphase composites endows liquid metal with many unconventional fluidic *** further push forward the advancement of this new area,the present article is dedicated to systematically outlining the scientific category of RTLMs multiphase flow physics and interpreting its fundamental and practical *** vision is to provide insights into promising developmental directions of RTLMs multiphase flow and thus facilitate synergetic research and progress among different ***,the traditional metal multiphase flow was briefly ***,we summarized the physics of RTLMs multiphase flow,the common types of liquid metals,the basic physical and chemical properties of their multiphase flow and governing equations,*** that,various typical driving modalities and manipulation methods of RTLMs were ***,important implementations of RTLMs multiphase flow into thermal management,energy harvesting,catalysis,soft machines,biomedicine,and printed electronics were ***,the multiphase flow physics of RTLMs is currently still in its incubation stage and there exist tremendous opportunities and challenges which are worth further pursuing in the coming time.

关键词： room-temperature liquid metals multiphase flow physics composite solution nanofluids fluid mechanics micro-/nanodroplets