Design and Shape Control Ability Simulation of New Generation Varying Contact Length Backup Roll in Hot Rolling

Wenquan Sun,Jian Shao,Anrui He 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.4

Backup roll technology plays an important role in hot strip mill shape control. Varying contact length backup roll (VCR) technology in hot strip mill can increase transverse stiffness of loaded gap, heighten control effect of roll bending, and improve distribution of contact force between backup roll and work roll. However it appears to lack coordination with high-order curve work roll. A new objective function of new generation varying contact length backup roll (VCR plus) design curve is established with considering high-order work roll contour, and simulation is carried out to verify the effectiveness of VCR plus by a two dimensional variable thickness finite element method. The result shows that distribution of contact force between backup roll and work roll is more even in VCR plus technology, and which can extend the useful life of backup roll.

Laboratory and field evaluation of the repellency of six preservatives to red imported fire ants (Hymenoptera: Formicidae)

Wenquan Qin,Hongpeng Xiong,YuzhenWen,XiujunWen,HuiWang,Yihan Fang,TaoMa,Zhaohui Sun,Xiaoyang Chen,Cai Wang 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

Baiting is widely applied for the detection and control of the red imported fire ants, Solenopsis invicta Buren. Adding preservatives into baits would prevent microbial contamination during production and storage, and might extend period of bait attractiveness in the field. However, it is not known if preservatives are repellent to S. invicta. In the present study, potential effects of six commonly used preservatives (potassiumsorbate, sodium benzoate, sodium diacetate, sodium dehydroacetate, calcium propionate, and nisin) on the foraging behaviors of S. invicta foragers were evaluated under laboratory and field conditions. Four-choice tests (laboratory study) showed that the number of foraging ants on the preservative-treated (immersed in 2000-, 5000-, or 10,000-ppm solution for 30 min) and control (immersed in distilled water for 30 min) food was similar, with an exception of sodium dehydroacetate, which significantly decreased the number of foraging ants at the three tested concentrations. Interestingly, 46%, 58% and 71% of the food items treated with 2000-, 5000- and 10,000- ppm solutions of sodium dehydroacetate were buried with soil particles, respectively, whereas only 17% of the control food was similarly buried. Multiple-choice tests (field study) showed that food treated with the 5000- or 10,000-ppm solution of sodium dehydroacetate attracted significantly fewer S. invicta workers compared to other preservatives and the controls. Our study showed that the use of sodiumdehydroacetate should be avoided during the production of aqueous-based or liquid baits against S. invicta.

Research on the Comprehensive Control Strategy of Over-welding Based on Decoupling- Design for Tandem Cold Mills

Jian Shao,Wenquan Sun,Anrui He 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.3

The strategies of the welding seam dynamic passing control and feasible loose edge rolling technology are put forward. In the process of cold mill welding, by dynamic regulation roll-gap, bending force and stand speed. The control strategy of reducing tensions between stands and strip edge is achieved. At the same time, the decoupling control strategy of plate shape and thickness can reduce the influence of roll-gap on plate shape and of bending force and stand speed on the steel thickness. Simulation analysis and practical application show that the technology effectively reduces the occurrence of steel strip fracture of tandem cold mill units.

Rapid Stress Analytical Solutions of Steel Strips Subjected to Non-uniform Tensile Loads Based on New Symplectic Method

Haijun Yu,Anrui He,Wenquan Sun,Chihuan Yao,Chao Liu 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5

This paper deals with the stress distribution problem of steel strips subjected to non-uniform tensile loads at both ends, which induce the transverse in-plane compressive stress and is important for researching the transverse buckling of the steel strip. For stress distribution problem, the traditional fi nite element method (FEM) has acceptable accuracy while it takes too long computing time to be applied to on-site production and the semi-inverse analytical method needs to preset the form of stress solution and gets the solution with a certain error. Thence, a rapid symplectic analytical method for solving stress distribution problem of steel strips is presented, which is based on the Hamiltonian system unlike other traditional method based on the Lagrangian system. Furthermore, the rational and rigorous derivation without any forecast about the form of solution makes the stress result have high precision with short computing time. Finally, the symplectic method is demonstrated be more effi cient and suitable in the on-line calculation by comparing with FEM.

A Rapid Online Calculation Method of Three-dimensional Plastic Deformation in Strip Rolling

Jian Shao,Chihuan Yao,Chaochao Chen,Wenquan Sun,Anrui He 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

Three-dimensional strip plastic deformation model is a key part of shape setup model in hot rolling. The numerical efficiency, accuracy and stability of the method are the main factors that may restrict its online application. Considering the theoretical limitations of existing models, basic equations include equilibrium equations with the effect of shear stress, constitutive equations based on incremental theory, and lubricated friction with the respective coefficients of friction at longitudinal and transverse direction. After normalization of parameters and the asymptotic analysis, the strip plastic deformation model is established, and solved by finite volume method and BICGSTAB algorithm to get the transverse distribution of rolling force of each stand. Compared to the finite element model established by ANSYS software, the new model has reliable results and a short computation time of 31 milliseconds, which show its feasibility of online application.

Mechanism of capacity fade of MCMB/Li_1.1[Ni_1/3Mn_1/3Co_1/3]_0.9O₂ cell at elevated temperature and additives to improve its cycle life

Amine, Khalil,Chen, Zonghai,Zhang, Z.,Liu, Jun,Lu, Wenquan,Qin, Yan,Lu, Jun,Curtis, Larry,Sun, Yang-Kook Royal Society of Chemistry 2011 Journal of materials chemistry Vol.21 No.44

<P>The performance degradation of graphite/Li<SUB>1.1</SUB>[Ni<SUB>1/3</SUB>Mn<SUB>1/3</SUB>Co<SUB>1/3</SUB>]<SUB>0.9</SUB>O<SUB>2</SUB> lithium-ion cells at elevated temperature was investigated. The electrochemical data suggest that the migration of dissolved transition metals from the cathode to the anode is the key contributor to the performance degradation. With the help of density function theory calculations, lithium difluoro[oxalato] borate was tested to be an effective electrolyte additive to mitigate the performance degradation of lithium-ion cells. The application of this novel electrolyte additive was found to significantly improve both the life and safety characteristics of graphite/Li<SUB>1.1</SUB>[Ni<SUB>1/3</SUB>Mn<SUB>1/3</SUB>Co<SUB>1/3</SUB>]<SUB>0.9</SUB>O<SUB>2</SUB> lithium-ion cells.</P> <P>Graphic Abstract</P><P>The performance degradation of graphite/Li<SUB>1.1</SUB>[Ni<SUB>1/3</SUB>Mn<SUB>1/3</SUB>Co<SUB>1/3</SUB>]<SUB>0.9</SUB>O<SUB>2</SUB> lithium-ion cells at elevated temperature was investigated. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1jm11584g'> </P>

No-substrate and low-moisture conditions during pupating adversely affect Ectropis grisescens (Lepidoptera: Geometridae) adults

Huifang Wang,Shiping Liang,TaoMa,Qiang Xiao,Panrong Cao,Xuan Chen,Wenquan Qin,Hongpeng Xiong,Zhaohui Sun,XiujunWen,Cai Wang 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.2

Ectropis grisescens Warren (Lepidoptera: Geometridae) is an important defoliator pest of the tea plant, Camellia sinensis L. Our previous studies showed that E. grisescens pupae had significantly lower body water content when they pupated in the dry soil (20%-moisture) than those that pupated in the wetter soil (50%- or 80%-moisture). However, it is still unclear whether low-moisture conditions during pupating would further influence the physiological and fitness traits of adults. In the present study, E. grisescens individuals were allowed to pupate in 20%-, 50%- or 80%-moisture soil (silt loam), or in containers without soil (no-substrate conditions) in the laboratory. No significant difference in emergence was detected among different pupating conditions. However, female moths that emerged from 20%-moisture soil had significantly lower body water content compared to 80%-moisture soil, whereas the body water content of males was similar among the four treatments. The paired moths that emerged from 20%-moisture soil laid significantly fewer eggs than those that emerged from 50%- moisture soil. In addition, the number of hatched offerings (larvae) were significantly less when the adults previously pupated in no-soil containers compared to 50%-moisture soil. The longevity of adults was shortest when they emerged from 20%-moisture soil. Our study showed that the no-substrate and low-moisture conditions during pupating adversely affected E. grisescens adults.