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NUMERICAL INVESTIGATION OF PERFORMANCE OF AN AXIAL-FLOW PUMP WITH INDUCER

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Journal of Hydrodynamics 2007年第6期19卷 705-711页

作者： LI Yao-jun wang fu-jun College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

The interaction of flow through the inducer and impeller of an axial-flow pump equipped with an inducer has significant effect on its performance. This article presents a recent numerical investigation on this topic. The studied pump has an inducer with 3 blades mounted on a conical hub and a 6-blade impeller. The blade angle of the impeller is adjustable to generate different relative circumferential angles between the inducer blade trailing edge and the impeller blade leading edge. A computational fluid dynamics code was used to investigate the flow characteristics and performance of the axial-flow pump. For turbulence closure, the RNG k-ε model was applied with an unstructured grid system. The rotor-stator interaction was treated with a Multiple Reference Frame （MRF） strategy. Computations were performed in different cases： 7 different relative circumferential angles （ Δθ ） between the inducer blade trailing edge and the impeller blade leading edge, and 3 different axial gaps （G） between the inducer and the impeller. The variation of the hydraulic loss in the rotator was obtained by changing Δθ . The numerical results show that the pressure generated is minimum in the case of （ G = 3%D）, which indicates that the interference between inducer and impeller is strong if the axial gap is small. The pump performances were predicted and compared to the experimental measurements. Recommendations for future modifications and improvements to the pump design were also given.

关键词： axial-flow pump inducer CFD numerical simulation of flow

Preparation and Mechanical Properties of a Novel Textile Pad for Wound Debridement

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Journal of Donghua University(English Edition) 2014年第5期31卷 621-624页

作者： fu Yi-jun wang Lu wang fu-jun wang Wen-zu MENG Si-yi Key Laboratory of Textile Science & Technology Ministry of Education Donghua University Shanghai 201620 China College of Textiles Donghua University Shanghai 201620 China

Various types of wound debridement approaches are currently available in clinical practice such as autolytie, enzymatic. biodebridement, mechanical, and surgical debridemenl techniques. A critical look at these various options can explain their potential but also their limitations. In this study, a novel textile pad, which is composed of polyester filaments on the fleecy side and a bioeompatible coating on the opposite side, was made to provide a safe, inexpensive, easier and especially more efficient debridement process that can be used in all healthcare settings by all healthcare practitioners. Eighteen kinds of samples were prepared with different pile density, ground yarn count and coating amount. Dimensional morphology, stitch density, mass per unit area and mechanical properties were investigated to study the intrinsic relationship of structure and properties of textile pad for wound debridement. Results showed that tensile strength and suturing strength at piped site increased obviously with the increment of ground yarn count, while the amount of coating could also have a slight impact on these two properties. However, compressive load was mainly affected by pile density, with no obvious relation to ground yarn count and coating amount.

关键词： textile pad wound debridement pile density mechanicalproperties

CFD SIMULATION OF 3D FLOW IN LARGE-BORE AXIAL-FLOW PUMP WITH HALF-ELBOW SUCTION SUMP

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Journal of Hydrodynamics 2006年第2期18卷 243-247页

作者： wang fu-jun LI Yao-jun CONG Guo-hui wang Wen-e wang Hai-song College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

Numerical simulations of 3D turbulent flow in a large-bore axial-flow pump coupled with half-elbow suction sump were perlbrmed by using CFD approach. The numerical model and velocity and pressure distributions in entire flow passage were presented. The obvious backflow in half-elbow suction sump and strong flow nonuniformity at suction sump outlet were observed, whereas these phenomena were not observed in existing studies performed for a separate suction sump by either experimental or numerical approach. This result indicates that the interaction between half-elbow suction sump and impeller has significant effect on the flow distribution in the pump passage. The change of pump efficiency caused by the interaction was discussed,

关键词： axial flow pump half elbow suction sump,CFD

Black Hole Entropy with Modified Dispersion Relations

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Communications in Theoretical Physics 2009年第8期52卷 261-263页

作者： wang fu-jun GUI Yuan-Xing ZHANG Yu School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

There is much interest in resolving the quantum corrections to Bekenstein-Hawking entropy with a large length scale limit. The leading correction term ＆ given by the logarithm of black hole area with a model-dependent coefficient. Recently the research for quantum gravity implies the emergence of a modification of the energy-momentum dispersion relation （MDR）, which plays an important role in the modified black hole thermodynamics. In this paper, we investigate the quantum corrections to Bekenstein-Hawking entropy in four-dimensional Sehwarzschild black hole and Reissner-Nordstrom black hole respectively based on MDR.

关键词： black hole entropy dispersion relation

Influence of Microcirculatory Dysfunction on Myocardial Injury after Cardiopulmonary Resuscitation

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Biomedical and Environmental Sciences 2022年第4期35卷 334-344页

作者： YANG jun DONG Gui Juan wang Hong Wei ZHAO Xin wang fu jun ZHANG Jian GUO Shu Bin Emergency Medicine Clinical Research Center of Beijing Chaoyang Hospital Capital Medical UniversityBeijing Key Laboratory of Cardiopulmonary Cerebral ResuscitationBeijing 100020China

Objective This study aimed to examine the effects of microcirculatory dysfunction and 654-1intervention after cardiopulmonary resuscitation on myocardial *** Landrace pigs were divided into a sham operation group(S group,n=6),ventricular fibrillation control group(VF-C group,n=8)and 654-1 intervention group(VF-I group,n=8).Hemodynamics was recorded at baseline,at recovery of spontaneous circulation(ROSC),and 1 h,2 h,4h and 6 h *** dark field(SDF)technology was used to evaluate and monitor the microcirculation flow index,total vessel density,perfusion vessel ratio,De-Backer score,and perfusion vessel density in animal viscera at various time *** After administration of 654-1 at 1.5 h post-ROSC,the hemodynamics in the VF-I group,as compared with the VF-C group,was significantly *** visceral microcirculation detected by SDF was also significantly improved in the VF-I *** observed through electron microscopy,significantly less myocardial tissue injury was present in the VF-I group than the VF-C *** Administration of 654-1 inhibited excessive inflammatory by improving the state of visceral microcirculation.

关键词： Cardiopulmonary resuscitation Post-cardiac arrest syndrome Microcirculation dysfunction Myocardial injury Anisodamine hydrobromide(654-1)

A PARTIALLY-AVERAGED NAVIER-STOKES MODEL FOR HILL AND CURVED DUCT FLOW

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Journal of Hydrodynamics 2011年第4期23卷 466-475页

作者： MA Jia-mei wang fu-jun YU Xin LIU Zhu-qing College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

Turbulent flows past hill and curved ducts exist in many engineering applications. Simulations of the turbulent flow arc carried out based on a newly developed technique, the Partially-Averaged Navier-Stokes （PANS） model, including separation, recirculation, reattachment, turbulent vortex mechanism. The focus is on how to accurately predict typical separating, reattaching and secondary motion at a reasonable computational expense. The effect of the parameter, the unresolved-to-total ratio of kinetic energy （ fk ）, is examined with a given unresolved-to-total ratio of dissipation （ fE ） for the hill flow with a much coarser grid system than required by the LES. An optimal value of fk can be obtained to predict the separation and reattachment locations and for more accurate simulation of the resolved turbulence. In addition, the turbulent secondary motions are captured by a smaller fi as compared with the RANS method with the same grid.

关键词： Partially-Averaged Navier-Stokes (PANS) flow separation recirculation reattachment resolved turbulence

Creation of gene-specific rice mutants by AvrXa23-based TALENs

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Journal of Integrative Agriculture 2017年第2期16卷 424-434页

作者： wang fu-jun wang Chun-lian ZHENG Chong-ke QIN Teng-fei GAO Ying LIU Pi-qing ZHAO Kai-jun National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI) Institute of Crop SciencesChinese Academy of Agriculture Sciences (CAAS) College of Agriculture Guangxi University

Transcription activator-like effector （TALE） nucleases （TALENs） are increasingly used as a powerful tool for genome edit- ing in a variety of organisms. We have previously cloned the TALE-coding gene avrXa23 from Xanthomonas oryzae pv. oryzae and developed an AvrXa23-based assembly system for designer TALEs or TALENs. Here, we exploit TALENs to induce mutagenesis of the rice ethylene response factor （ERF） transcription factor OsERF922 for testing the gene-editing efficiency of AvrXa23-based TALENs system. A pair of TALENs （T-KJ9/KJ 10） was assembled and their nuclease activities were first confirmed in rice protoplast transient assay. The TALENs-expressing construct pT-KJ9/KJ10 was then used for rice transformation. We observed targeting somatic mutagenesis frequency of 15.0% in positive transgenic rice calli and obtained two mutant plants with nucleotide deletion or insertion at the designer target region. Our work demonstrates that the AvrXa23-based TALENs system can be used for site-specific genome editing in rice.

关键词： TAL effector nucleases AvrXa23 targeting OsERF922 genome editing rice

A New Industrial Intrusion Detection Method Based on CNN-BiLSTM

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Computers, Materials & Continua 2024年第6期79卷 4297-4318页

作者： jun wang Changfu Si Zhen wang Qiang fu College of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China

Nowadays,with the rapid development of industrial Internet technology,on the one hand,advanced industrial control systems(ICS)have improved industrial production ***,there are more and more cyber-attacks targeting industrial control *** ensure the security of industrial networks,intrusion detection systems have been widely used in industrial control systems,and deep neural networks have always been an effective method for identifying cyber *** intrusion detection methods still suffer from low accuracy and a high false alarm ***,it is important to build a more efficient intrusion detection *** paper proposes a hybrid deep learning intrusion detection method based on convolutional neural networks and bidirectional long short-term memory neural networks(CNN-BiLSTM).To address the issue of imbalanced data within the dataset and improve the model’s detection capabilities,the Synthetic Minority Over-sampling Technique-Edited Nearest Neighbors(SMOTE-ENN)algorithm is applied in the preprocessing *** algorithm is employed to generate synthetic instances for the minority class,simultaneously mitigating the impact of noise in the majority *** approach aims to create a more equitable distribution of classes,thereby enhancing the model’s ability to effectively identify patterns in both minority and majority *** the experimental phase,the detection performance of the method is verified using two data *** results show that the accuracy rate on the CICIDS-2017 data set reaches 97.7%.On the natural gas pipeline dataset collected by Lan Turnipseed from Mississippi State University in the United States,the accuracy rate also reaches 85.5%.

关键词： Intrusion detection convolutional neural network bidirectional long short-term memory neural network multi-head self-attention mechanism

具有力学与结构稳定性多组分纤维肌腱防粘连膜制备及性能

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生物医学工程与临床 2024年第5期28卷 602-610页

作者：汪孟姣吴新康王富军王璐黄超李超婧东华大学纺织面料技术教育部重点实验室上海201620 东华大学纺织学院上海201620 上海昊海生物科技股份有限公司上海201103

目的引入疏水聚己内酯(PCL),改善壳聚糖(CS)/聚乙烯醇(PVA)混纺膜的性能,研究制备性能优良的肌腱防粘连材料的可行性。方法实验以具有低蛋白吸附性的PVA、成纤维细胞增殖抑制作用的CS和疏水性聚合物PCL为原料,通过共轭静电纺丝技术制备... 详细信息

目的引入疏水聚己内酯(PCL),改善壳聚糖(CS)/聚乙烯醇(PVA)混纺膜的性能,研究制备性能优良的肌腱防粘连材料的可行性。方法实验以具有低蛋白吸附性的PVA、成纤维细胞增殖抑制作用的CS和疏水性聚合物PCL为原料,通过共轭静电纺丝技术制备不同组分(CS∶PCL∶PVA=3∶5∶2、3∶4∶3、3∶3∶4、3∶2∶5)的纤维膜(CS/PCL/PVA膜,简称CPA膜)。采用傅里叶红外光谱仪分析CPA膜组成,扫描电子显微镜、万能实验仪及模拟体液预处理的方式探究了PVA和PCL含量对形貌、力学、结构稳定性的影响,进一步使用热重分析仪及细胞实验分析CPA膜热性能、细胞毒性和黏附性。结果CPA膜红外谱图中同时出现CS、PCL及PVA特征峰,且未产生新的基团或化学键。根据体液稳定性与微观形貌测试结果可知,PCL的引入一方面降低了CPA膜的纤维平均直径;与CS/PVA膜相比,CPA膜(CS∶PCL∶PVA=3∶5∶2)的断裂强度和伸长率分别提高了约60%和40%,弹性模量相当且与文献数据一致。另一方面改善CPA膜湿环境下力学性能失效和卷曲皱缩的问题。热重分析结果显示多组分纤维膜分解温度在250℃~600℃,而实际应用环境温度显著低于热分解温度,具有热稳定性,即防粘连膜不会因温度而导致结构性能的损失。细胞实验结果显示,CPA膜(CS∶PCL∶PVA=3∶5∶2)具有良好的细胞相容性及一定的体外抗细胞黏附性。第3天CA和CPA纤维膜的细胞存活率分别为(96.533±0.341)%、(101.877±11.001)%(P>0.05)。培养7 d后,CPA光密度值为0.223±0.002,显著低于CA(0.292±0.007)。结论CPA膜具有增强的力学强度与湿态稳定性,更适应肌腱部位的受力环境。表现出更优异的抗细胞黏附效果,CS∶PCL∶PVA的质量比为3∶5∶2为最优参数的防粘连膜材料。具有肌腱术后防粘连领域的应用潜力。

关键词：防粘连屏障静电纺丝纤维膜肌腱湿态稳定性

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