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Ultrasonic measurement of tie-bar stress for die-casting machine

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Frontiers of Mechanical Engineering 2022年第1期17卷 188-201页

作者： Chaojie ZHUO Peng ZHAO Kaipeng JI Jun XIE Sheng YE Peng CHENG Jianzhong FU The State Key Laboratory of Fluid Power and Mechatronic Systems College of Mechanical EngineeringZhejiang UniversityHangzhou 310027China The Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027China ningbo Haitian Die-Casting Equipment Co. Ltd.Ningbo 315821China

In die casting,the real-time measurement of the stress of the tie-bar helps ensure product quality and protect the machine ***,the traditional magnetic-attached strain gauge is installed in the mold and product operating area,which hinders the loading and unloading of the mold and the collection of die *** this paper,a method for real-time measurement of stress using ultrasonic technology is *** stress variation of the tie-bar is analyzed,and a mathematical model between ultrasonic signal and stress based on acoustoelastic theory is *** experiments show that the proposed method agrees with the strain gauge,and the maximum of the difference square is only 1.5678(MPa)***,single-factor experiments are conducted.A higher ultrasonic frequency produces a better measurement accuracy,and the mean of difference squares at 2.5 and 5 MHz are 2.3234 and 0.6733(MPa)_(2),*** accuracy is insensitive to probe location and tonnage of the die-casting ***,the ultrasonic measurement method can be used to monitor clamping health status and inspect the dynamic pulling force of the *** approach has the advantages of high precision,high repeatability,easy installation,and noninterference,which helps guide the production in die casting.

关键词： die-casting tie-bar stress acoustoelastic theory ultrasonic measurement dynamic inspection

Hydroxycoumarin efficiently inhibits spring viraemia of carp virus infection in vitro and in vivo

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Zoological Research 2020年第4期41卷 395-409页

作者： Lei Liu Da-Wei Song Guang-Lu Liu Li-Peng Shan Tian-Xiu Qiu Jiong Chen State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingboZhejiang 315211China Laboratory of Biochemistry and Molecular Biology School of Marine SciencesMeishan CampusNingbo UniversityNingboZhejiang 315832China Key Laboratory of Applied Marine Biotechnology of Ministry of Education Meishan CampusNingbo UniversityNingboZhejiang 315832China School of Chemistry&Chemical Engineering Zhoukou Normal UniversityZhoukouHenan 466001China

Spring viremia of carp virus(SVCV)causes devastating losses in *** has an advantageous structure for the design of novel antiviral agents with high affinity and *** this study,we evaluated a hydroxycoumarin medicine,i.e.,7-(6-benzimidazole)coumarin(C10),regarding its anti-SVCV effects in vitro and in *** showed that up to 12.5 mg/L C10 significantly inhibited SVCV replication in the epithelioma papulosum cyprini(EPC)cell line,with a maximum inhibitory rate of>97%.Furthermore,C10 significantly reduced cell death and relieved cellular morphological damage in SVCV-infected *** mitochondrial membrane potential(ΔΨm)also suggested that C10 not only protected mitochondria,but also reduced apoptosis in SVCVinfected *** in vivo studies,intraperitoneal injection of C10 resulted in an anti-SVCV effect and substantially enhanced the survival rate of virusinfected ***,C10 significantly enhanced antioxidant enzyme activities and decreased reactive oxygen species(ROS)to maintain antioxidant-oxidant balance within the host,thereby contributing to inhibition of SVCV *** up-regulation of six interferon(IFN)-related genes also demonstrated that C10 indirectly activated IFNs for the clearance of SVCV in *** was beneficial for the continuous maintenance of antiviral effects because of the low viral loads in ***,C10 is suggested as a therapeutic agent with great potential against SVCV infection in aquaculture.

关键词： vivo thereby maintain

Ultrafast cyclic voltammetry with asymmetrical potential scan

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Chinese Chemical Letters 2008年第1期19卷 85-88页

作者： Zhi Yong Guo Xiang Qin Lin Faculty of Materials Science and Chemical Engineering The State Key Laboratory Base of Novel Functional Materials and Preparation Science Ningbo University Ningbo 315211 China Department of Chemistry University of Science and Technology of China Hefei 230026 China

Based on the perfect ohmic drop compensation by online electronic positive feedback, ultrafast cyclic voltammetry with asymmetrical potential scan is achieved for the first time, with the reduction of anthracene acting as the test system. Compared with the traditional cyclic voltammetry utilizing symmetrical triangular waveform as the excitation one, the new method allows a simpler approach to mechanistic analysis of ultrafast chemical reactions coupled with a charge transfer. And perhaps more important, it also provides a way to eliminate the interference of the adsorbed product in dynamic monitoring. 2007 Zhi Yong Guo. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ultrafast cyclic voltammetry Asymmetrical potential scan MV/s scan rates

Current understanding on the roles of gut microbiota in fish disease and immunity

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Zoological Research 2019年第2期40卷 70-76页

作者： Jin-Bo Xiong Li Nie Jiong Chen Laboratory of Biochemistry and Molecular Biology School of Marine Sciences Ningbo University Key Laboratory of Applied Marine Biotechnology of Ministry of Education Ningbo University

Intensive aquaculture has increased the severity and frequency of fish *** the functional importance of gut microbiota in various facets of host physiology,modulation of this microbiota is a feasible strategy to mitigate emerging diseases in *** achieve this,a fundamental understanding of the interplay among fish health,microbiota, and invading pathogens is *** commentary focuses on current knowledge regarding the associations between fish diseases,dysbiosis of gut microbiota,and immune responses. Furthermore,updated research on fish disease from an ecological perspective is discussed,including colonization resistance imposed by commensals and strategies used by pathogens to overcome *** also propose several directions for future research,such as exploration of the causal links between fish diseases and specific taxa,and identification of universal gut microbial biomarkers for rapid disease diagnosis.

关键词： microbiota fish disease immunity

3D analytical solution for a rotating transversely isotropic annular plate of functionally graded materials

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1038-1043页

作者： CHEN Jiang-ying CHEN Wei-qiu Faculty of Engineering Ningbo University Ningbo 315211 China Department of Civil Engineering Zhejiang University Hangzhou 310027 China

The analytical solution for an annular plate rotating at a constant angular velocity is derived by means of direct displacement method from the elasticity equations for axisymmetric problems of functionally graded transversely isotropic media. The displacement components are assumed as a linear combination of certain explicit functions of the radial coordinate, with seven undetermined coefficients being functions of the axial coordinate z. Seven equations governing these z-dependent functions are derived and solved by a progressive integrating scheme. The present solution can be degenerated into the solution of a rotating isotropic functionally graded annular plate. The solution also can be degenerated into that for transversely isotropic or isotropic homogeneous materials. Finally, a special case is considered and the effect of the material gradient index on the elastic field is illustrated numerically.

关键词： Functionally graded materials Transversely isotropic Rotating annular plate Analytical solution

Antiviral effects of natural small molecules on aquatic rhabdovirus by interfering with early viral replication

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Zoological Research 2022年第6期43卷 966-976页

作者： Yan Zhou Tian-Xiu Qiu Yang Hu Lei Liu Jiong Chen State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products Ningbo UniversityNingboZhejiang 315211China Laboratory of Biochemistry and Molecular Biology School of Marine SciencesMeishan CampusNingbo UniversityNingboZhejiang 315832China Key Laboratory of Applied Marine Biotechnology of Ministry of Education Meishan CampusNingbo UniversityNingboZhejiang 315832China

Spring viremia of carp virus(SVCV)is globally widespread and poses a serious threat to aquatic ecology and aquaculture due to its broad host *** develop effective agents to control SVCV infection,we selected 16 naturally active small molecules to assess their anti-SVCV ***,dihydroartemisinin(DHA)(100μmol/L)and(S,S)-(+)-tetrandrine(TET)(16μmol/L)exhibited high antiviral effects in epithelioma papulosum cyprinid(EPC)cells,with inhibitory rates of 70.11%and 73.54%,*** possible antiviral mechanisms were determined as follows:*** with DHA and TET decreased viral particle infectivity in fish cells,suggesting that horizontal transmission of SVCV in the aquatic environment was disrupted;*** neither had an effect on viral adhesion,TET(but not DHA)interfered with SVCV entry into host cells(>80%),suggesting that TET may have an antiviral function in early viral *** in vivo study,both agents enhanced the survival rate of SVCV-infected zebrafish by 53.3%,significantly decreased viral load,and modulated the expression of antiviralrelated genes,indicating that DHA and TET may stimulate the host innate immune response to prevent viral ***,our findings indicated that DHA and TET had positive effects on suppressing SVCV infection by affecting early-stage viral replication,thus holding great potential as immunostimulants to reduce the risk of aquatic rhabdovirus disease outbreaks.

关键词： Spring viremia of carp virus Natural small molecules Antiviral effects Virus internalization Danio rerio

The time-dependent Ginzburg-Landau equation for the two-velocity difference model

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Chinese Physics B 2011年第8期20卷 130-135页

作者：吴淑贞程荣军葛红霞 Faculty of Science Ningbo University Department of Fundamental Course Ningbo Institute of TechnologyZhejiang University

A thermodynamic theory is formulated to describe the phase transition and critical phenomenon in traffic flow. Based on the two-velocity difference model, the time-dependent Ginzburg-Landau （TDGL） equation under certain condition is derived to describe the traffic flow near the critical point through the nonlinear analytical method. The corresponding two solutions, the uniform and the kink solutions, are given. The coexisting curve, spinodal line and critical point are obtained by the first and second derivatives of the thermodynamic potential. The modified Korteweg- de Vries （mKdV） equation around the critical point is derived by using the reductive perturbation method and its kink antikink solution is also obtained. The relation between the TDGL equation and the mKdV equation is shown. The simulation result is consistent with the nonlinear analytical result.

关键词： traffic flow two-velocity difference model TDGL equation mKdV equation

Optomechanical state transfer between two distant membranes in the presence of non-Markovian environments

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Chinese Physics B 2018年第12期27卷 177-181页

作者： Jiong Cheng Xian-Ting Liang Wen-Zhao Zhang Xiangmei Duan Department of Physics Ningbo UniversityNingbo 315211China Beijing Computational Science Research Center (CSRC) Beijing 100193China

The quantum state transfer between two membranes in coupled cavities is studied when the system is surrounded by non-Markovian environments. An analytical approach for describing non-Markovian memory effects that impact on the state transfer between distant membranes is presented. We show that quantum state transfer can be implemented with high efficiency by utilizing the experimental spectral density, and the performance of state transfer in non-Markovian environments is much better than that in Markovian environments, especially when the tunneling strength between the two cavities is not very large.

关键词： optomechanical systems non-Markovian effect quantum state transfer

Finite size effect of ions and dipoles close to charged interfaces

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Chinese Physics B 2010年第4期19卷 469-477页

作者：童朝晖诸跃进 Department of Physics Ningbo University

The modified dipolar Poisson-Boltzmann （MDPB） equation, where the electrostatics of the dipolar interactions of solvent molecules and also the finite size effects of ions and dipolar solvent molecules are explicitly taken into account on a mean-field level, is studied numerically for a two-plate system with oppositely charged surfaces. The MDPB equation is solved numerically, using the nonlinear Multigrid method, for one-dimensional finite volume meshes. For a high enough surface charge density, numerical results of the MDPB equation reveal that the effective dielectric constant decreases with the increase of the surface charge density. Furthermore, increasing the salt concentration leads to the decrease of the effective dielectric constant close to the charged surfaces. This decrease of the effective dielectric constant with the surface charge density is opposite to the trend from the dipolar Poisson Boltzmann （DPB） equation. This seemingly inconsistent result is due to the fact that the mean-field approach breaks down in such highly charged systems where the counterions and dipoles are strongly attracted to the charged surfaces and form a quasi two-dimensional layer. In the weak-coupling regime with the electrostatic coupling parameter （the ratio of Bjerrum length to Gouy-Chapman length） Ξ 〈 1, where the MDPB equation works, the effective dielectric constant is independent of the distance from the charged surfaces and there is no accumulation of dipoles near the charged surfaces. Therefore, there are no physical and computational advantages for the MDPB equation over the modified Poisson-Boltzmann （MPB） equation where the effect of dipolar interactions of solvent dipoles is implicitly taken into account in the renormalised dielectric constant.

关键词： dipole Poisson Boltzmann equation charged interface polarisation