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Modelling and analysis for a pilot relief valve using CFD method and deformation theory of thin plates

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Science China(Technological Sciences) 2015年第6期58卷 979-998页

作者： yuan xianJu guo KongHui School of Mechanical & Automotive Engineering South China University of Technology College of Automotive Engineering Jilin University KH Automotive Technologies (Changchun) Co. Ltd.

The current work is concerned with modelling and analysis for a pilot relief valve, thus successfully bringing a systematic method for designing and analyzing similar valves. The essence of the work is to solve two important problems, one for positions of the pilot valve influenced by flow force and the other is for the opening of the relief valve governed by a thin annular plate. The computational fluid dynamics(CFD) method is used to present the flow force. Using a series of experiments, the flow rate versus pressure drop shows the rationality of the CFD results. In order to obtain the opening of relief valve with higher accuracy, the large deflection theory of thin plates is adopted. An equivalent method for replacing the concentrated force is innovatively proposed so that all of the loads of the plates can be given by a unified expression, which reduces the number of the governing equations and intermediate boundary conditions. For presenting a very simple and reliable method for solving the governing equation, an unconstrained nonlinear optimization is innovatively introduced to solve the deflection of the thin annular plate. Being verified by finite-element method(FEM) of the relief valve, the equivalent method and optimization can solve deflection of thin plates rapidly and accurately. Reflected through a complete model for the pilot relief valve, the theoretical flow rate of the pilot relief valve is consistent with experimental conclusion. Once again, the comparisons bring us insight into the accuracy of the method adopted in the current work.

关键词： pilot valve relief valve modelling large deflection unconstrained nonlinear optimization

Relativistic Mean Field Study of the Z -- 117 Isotopic Chain

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Chinese Physics Letters 2010年第6期27卷 52-55页

作者： GAO yuan ZHANG Hong-Fei ZHANG Lei CHEN xi-Meng LI Jun-Qing guo Wen-Jun School of Information Engineering Hangzhou Dianzi University Hangzhou 310018 School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 College of Science University of Shanghai for Science and Technology Shanghai 200093

The properties of the Z = 117 isotopic chain are studied within the framework of the axially deformed relativistic mean field theory （RMFT） in the blocked BCS approximation. The ground-state properties, such as hinging energies, deformations as well as the possible α decay energies and lifetimes are calculated with the parameter set of NL-Z2 and compared with results from the finite range droplet model. The analysis by RMFT shows that the isotopes in the range of mass number A =291 ~ 300 exhibit higher stability, which suggests that they may be promising nuclei to be hopefully synthesized in the lab among the nuclei Z = 117.

关键词： Property Properties Isotopes Energy

Unveiling the dynamic instability mechanism of microstructure transformation in faceted oxide eutectic composite ceramics

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Journal of Materials Science & Technology 2023年第13期144卷 224-234页

作者： Haijun Su yuan Liu Qun Ren Zhonglin Shen Min guo xi Li Jun Zhang Lin Liu Hengzhi Fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Department of Material Science and Engineering Shanghai UniversityShanghai 200072China

Microstructure control is a great challenge in the high-temperature gradient directional solidification of eutectic composite ceramics due to the complex solidification ***,the microstructure trans-formation of faceted Al_(2)O_(3)/Er_(3)Al_(5)O_(12) thermal emission eutectic composite ceramics is explored over wide ranges of compositions(13.5 mol%-22.5 mol%Er_(2)O_(3))and solidification rates(2-200μm/s).Entirely cou-pled eutectics with primary phases suppressed are fabricated and the coupled zone is broadened in a wide range of 15.5 mol%-22.5 mol%Er_(2)O_(3) at low solidification *** competitive growth between eutectic and dendrite is evaluated on the basis of the maximum interface temperature *** ad-dition,the mechanisms of irregular eutectic spacing selection and adjustment under different solidifi-cation rates are revealed based on Magnin-Kurz model.A successful prediction of lamellar to rod-like eutectics is achieved associated with the dynamic instability of lamellar eutectic and the corresponding enlarged coexistence region is mapped based on the interface *** to the well mi-crostructure tailoring,the flexural strength of Al_(2)O_(3)/Er_(3)Al_(5)O_(12) eutectic composite ceramics has improved from 508 MPa up to 1800 MPa due to the refined eutectic spacing with low *** eutectic composite ceramics show strong selective optical absorption and the intensity increases with the refin-ing *** as-designed Al_(2)O_(3)/Er_(3)Al_(5)O_(12) composites with microstructural tailoring have great potential as integrations of structural and functional materials.

关键词： Directional solidification Laser floating zone melting Al_(2)O_(3)/Er_(3)Al_(5)O_(12)eutectic composite ceramics Eutectic growth mechanism Microstructure transformation

Characterization and functional analysis of β-1,3-galactosyltransferase involved in Cry1Ac resistance from Helicoverpa armigera(Hübner)

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Journal of Integrative Agriculture 2015年第2期14卷 337-346页

作者： ZHANG Li-li LIANG Ge-mei GAO xi-wu CAO Guang-chun guo Yu-yuan College of Agriculture and Biotechnology China Agricultural University State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

Carbohydrate chains are the principal antigens by which Bacillus thuringiensis（Bt） identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of insects. Receptor proteins, such as aminopeptidase N and alkaline phosphatase, are glycoproteins. Cadherin is another cell surface receptor protein which has potential glycosylation sites. Glycosyltransferase is very important for the synthesis and modification of receptor proteins. It can indirectly influence the function of Bt. The 1 950 bp full-length c DNA encoding β-1,3-galactosyltransferase was cloned from the the midgut of Helicoverpa armigera by degenerative PCR combined with RACE techniques（GAL-Harm, Gen Bank accession no.： GQ904195.1） with two potential N-glycosylation sites（^157NNTI^160 and ^272NKTL^275）. Protein sequence alignments revealed that H. armigera β-1,3-galactosyltransferase shared high identity with β-1,3-galactosyltransferase in other insect species. The expression level of the β-1,3-galactosyltransferase gene in Cry1Ac-resistant H. armigera larvae was 9.2-fold higher than that in susceptible strain. The function of β-1,3-galactosyltransferase was investigated using RNAi technique. The result showed Cry1 Ac enhanced the toxicity against the si RNA-treated larvae compared with non-si RNA-treated ones, which indicated β-1,3-galactosyltransferase played an important role for the insecticidal toxicity of Cry1 Ac in H. armigera.

关键词： β-1 3-galactosyltransferase Cry1Ac resistance Helicoverpa armigera RNAi

Comparative Analysis of Cry1Ac Toxin Oligomerization and Pore Formation Between Bt-Susceptible and Bt-Resistant Helicoverpa armigera Larvae

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Journal of Integrative Agriculture 2012年第11期11卷 1845-1851页

作者： LI Yi-ping WU Jun-xiang LIU Chen-xi yuan xiang-qun WU Kong-ming LIANG Ge-mei guo Yu-yuan Key Laboratory of Applied Entomology " Key Laboratory of Plant Protection Resources and Pest Management Ministry of Education~ College of Plant Protection Northwest Agriculture and Forestry University Yangling 712100 P.R.China State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China

With the long-term use of Bacillus thuringiensis （Bt） insecticide and expansion of CrylA-expressing transgenic plants, some insect pests have developed resistance to Bt in open fields, greenhouses, and in the laboratory. Bt resistance is complex and there appear to be different ways for resistance development. Understanding the Bt resistance mechanisms is critical to prolong its usefulness. In this article, Bt receptors, the cadherin and aminopeptidase N （APN）, in brush border membrane vesicles （/3BMV） of Helicoverpa armigera were examined in both CrylAc-susceptible （96S） and CrylAc- resistant （LF120） strains, to compare CrylAc toxin oligomerization and pore formation in these two strains. CrylAc toxin oligomerization and pore formation in these two strains were compared. Results showed that cadherin and aminopeptidase N proteins could express normally in both susceptible and resistant 11. armigera strains. The ability to form CrylAc oligomers and ion channels on BBMVs was also not significantly different between these two strains.

关键词： Helicoverpa armigera Bt resistance oligomerization pore formation

The LB Films of Dansyl Chloride Labeled Octadecylamine and Its Fluorescence Lifetime

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Chinese Chemical Letters 2000年第10期11卷 921-924页

作者： Hai Ning CUI guo Liang yuan Wei LI Wen Yun WANG Shi Quan xi Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistrythe Chinese Academy of SciencesChangchun 130022 Changchun Institute of Post and Telecommunication Changchun 130012

Octadecylamine was derivatized with dansyl chloride (5-dimethylaminonaphthalene-1-sulfonyl chloride) In order to simplify and understand the LB films of fluorescent probe labeling proteins. its monolayer and multilayers in the absence and presence of stearic acid were deposited by LB technique. Fluorescence spectra and lifetimes of the fluorescent products were studied to elucidate the microenvironment of molecules in the LB films.

关键词： LB film fluorescent probe labeling fluorescent spectra and lifetime

Two-in-one:A pooled analysis of primary hepatic neuroendocrine carcinoma combine d/collide d with hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 399-403页

作者： Jia-xi Mao Fei Teng Ke-Yan Sun Cong Liu guo-Shan Ding Wen-yuan guo Department of Liver Surgery and Organ Transplantation Changzheng HospitalNavy Medical UniversityShanghai 200003China

To the Editor:Primary hepatic neuroendocrine carcinoma(PHNEC)combined/collided with hepatocellular carcinoma(HCC)is a rare and intriguing disease with characteristics of two histologically different ***,a combined type refers to the cases in which hepatic neuroendocrine carcinoma(HNEC)and HCC components intermingle with each other and cannot be clearly separated in the transitional areas,while a collision type refers to those in which the two distinct cancers occurred simultaneously and *** it is difficult to readily distinguish these two *** searched PubMed,Medline,China Science Periodical Database,and VIP Database with the publication from January 1980 to January 2019,using the keywords(“hepatic neuroendocrine carcinoma”or“HNEC”)and(“hepatocellular carcinoma”or“HCC”).After manually excluding records on secondary HNEC and other types of liver cancer,a total of 28 cases in 24 reports[1–24]were identified and summarized in Table 1.

关键词： hepatic hepatocellular combine

Nonlinear Forced Vibration of Cantilevered Pipes Conveying Fluid

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Acta Mechanica Solida Sinica 2018年第1期31卷 32-50页

作者： Zhi-yuan Liu Lin Wang xi-Ping Sun Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China Tianjin Research Institute Water Transport Engineering M.O.T. Test Detection Center of Water Transport Engineering Tianjin 300356 China

The nonlinear forced vibrations of a cantilevered pipe conveying fluid under base excitations are explored by means of the full nonlinear equation of motion, and the fourth- order Runge-Kutta integration algorithm is used as a numerical tool to solve the discretized equations. The self-excited vibration is briefly discussed first, focusing on the effect of flow velocity on the stability and post-flutter dynamical behavior of the pipe system with parameters close to those in previous experiments. Then, the nonlinear forced vibrations are examined using several concrete examples by means of frequency response diagrams and phase-plane plots. It shows that, at low flow velocity, the resonant amplitude near the first-mode natural frequency is larger than its counterpart near the second-mode natural frequency. The second-mode frequency response curve clearly displays a softening-type behavior with hysteresis phenomenon, while the first-mode frequency response curve almost maintains its neutrality. At moderate flow velocity, interestingly, the first-mode resonance response diminishes and the hysteresis phenomenon of the second-mode response disappears. At high flow velocity beyond the flutter threshold, the frequency response curve would exhibit a quenching-like behavior. When the excitation frequency is increased through the quenching point, the response of the pipe may shift from quasiperiodic to periodic. The results obtained in the present work highlight the dramatic influence of internal fluid flow on the nonlinear forced vibrations of slender Pipes.

关键词： Pipe conveying fluid Base excitation Nonlinear dynamics Primary resonance,Superharmonie resonance Forced vibration

Aerobic granular sludge formation based on substrate availability:Effects of flow pattern and fermentation pretreatment

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 155-164页

作者： Quan yuan Hui Gong Hao xi Kaijun Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

The influences of flow patterns(mixed-flow and plug-flow)and fermentation pretreatment on aerobic granular sludge(AGS)formation with various substrate availability levels were investigated by running four identical laboratory-scale sequencing batch reactors(R1-R4),comparing two anaerobic feeding strategies and three kinds of substrates.R1 achieved faster granulation with a fast influent fill step followed by a modified anaerobic mixed-flow phase,but the AGS showed poorer stability with a cracked structure and a high suspended solids concentration in the *** anaerobic plug-flow feeding mode(with influent fed slowly from the bottom)in R2 provided deeper penetration depth for the substance to reach the core of A G S and accordingly strengthen A G S *** acidogenic upflow sludge bed reactor was introduced as a pretreatment to improve the AGS performance by enhancing glucose pre-fermentation(R4).AGS fed with mixed volatile fatty acids(VFA)after glucose fermentation showed similar performance compared with the reactor fed with acetate in the aspects of stability,structure,size distribution and nitrogen removal efficiency,and 74%similarity in the microbial *** actual wastewater with low VFA concentrations,fermentation treatment was suggested as a promising pretreatment for stable AGS granulation and operation.

关键词： Anaerobic plug-flow feeding mode Anaerobic mixed-flow mode Fermentation pretreatment Substrate gradient Penetration depth