http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
( Wei Bing Zhang ),( Xiao Ling He ),( Hong Na Liu ),( Hui Yuan Guo ),( Fa Zheng Ren ),( Wei Dong Gao ),( Peng Cheng Wen ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.8
In this paper, two statistical methods were applied to optimize medium components to improve the production of the milk-clotting enzyme by Bacillus amyloliquefaciens D4. First, wheat bran juice, skim milk powder, and Na2HPO4 were shown to have significant effects on D4 enzyme production using the Plackett?Burman experimental design. Subsequently, an optimal medium was obtained using the Box?Behnken method, which consisted of 3.31 g/l of skim milk powder, 5.0 g/l of sucrose, 0.1 g/l of FeSO4?7H2O, 0.1 g/l of MgSO4?7H2O, 0.1 g/l of MnSO4?2H2O, 0.1 g/l of ZnSO4?7H2O, 1.52 g/l of Na2HPO4, and 172.45 g/l of wheat bran juice. With this optimal medium, the milk-clotting enzyme production was remarkably enhanced. The milk-clotting enzyme activity reached 3,326.7 SU/ml after incubation of 48 h, which was 1.76-fold higher than that of the basic medium, showing that the Plackett?Burman design and Box?Behnken response surface method are effective to optimize medium components, and B. amyloliquefaciens D4 possessed a high rennet-producing capacity in the optimal medium.
The effects of grooves on wind characteristics of tall cylinder buildings
Wei-bin Yuan,Nan-ting Yu,Zhao Wang 한국풍공학회 2018 Wind and Structures, An International Journal (WAS Vol.26 No.2
For most full-scale tall buildings the Reynolds number of a flow field around a circular cylinder under strong wind is usually greater than 2107, which is difficult to achieve in most wind tunnel tests. To explore the wind characteristics of tall cylindrical buildings with equidirectional grooves from subcritical to transcritical flow (6.6104 Re 3.3105 and 9.9106 Re 7.2107), wind tunnel tests and full-scale large eddy simulations were carried out. The results showed that the rectangular-grooves narrow the wake width due to the downstream movement of the separation point and the deeper grooves cause smaller mean and fluctuating pressure while the peak pressure is little affected. Furthermore, the grooves lead to lower frequency of vortex shedding but the Strouhal number remains at the range from 0.15 to 0.35. The drag coefficient of the cylinders with grooves was found to be 2~3 times as large as that of smooth cylinders.
Effects of Micro Textured Sapphire Tool Regarding Cutting Forces in Turning Operations
Yuan Wei,Simon S. Park,김미루,이득우,Chaneel Park 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.4 No.2
In this study, the effects of microscale textures on a sapphire cutting tool were investigated. The texturing of microscale features on a solid surface allowed control of the tribological characteristics of the tool surface. Microscale geometrical characteristics on the rake face of the sapphire tools were obtained through micro-abrasive blasting. Tribological tests and cutting tests on an aluminum alloy workpiece were carried out, and the cutting forces were measured and analyzed. The effect of texture on adhesion of work material was investigated. Results showed that friction was minimized and cutting forces at the tool-chip interface of the textured tool were significantly reduced from those of a conventional tool. It was observed that the adhesion of work material was reduced by applying texture on the tool rake face.
Nonlinear Instability of Angle Section Beams under Uniformly Distributed Loads
Wei-bin Yuan,Wei Zhang,Jie Xu,Nan-ting Yu 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.2
This paper presents a study on the flattening behavior of angle-section beams of finite length subjected to uniformly distributed transverse loads. Analytical solutions for static instabilities of angle-section beams when they are bent about their weak axis are derived using energy methods. The basic assumptions used in the present study are that the total strain energy of an angle-section beam subjected to a uniformly distributed load can be simplified into a two-stage process. One is the bending response of the two legs behaving as the plate; the other is the bending response as a beam with flattened section. The nonlinear instability is derived by applying the minimum potential energy principle and the corresponding static critical moments associated with the section flattening-induced buckling are determined. To validate the analytical solution developed, nonlinear finite element analyses are also conducted. Good agreement between the present solution and the FEA results is demonstrated.
Nonlinear Bending of Box Section Beams of Finite Length Under Uniformly Distributed Loading
Wei-bin Yuan,Zhao-shui Bao,Nan-ting Yu,Shuang-shuang Zhu,Li-ping Wu 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.2
In this paper, the bending response of box-section beams of finite length is investigated by using energy methods. The basic assumptions used in the present study are that the total strain energy of a box-section beam subjected to uniformly distributed loading can be simplified into a two-stage analysis process. One is the local bending response of the webs and flanges behaving as plates; the other is the overall bending response of the beam with a deformed cross-section. Analytical solutions for both static and dynamic instabilities of box section beams of finite length subjected to transverse uniformly distributed loading are derived by applying the minimum potential energy principle. To validate the analytical solutions developed, geometric nonlinear finite element analyses are also conducted. Good agreement between the present solutions and the FEA results is demonstrated. Finally, the effects of beam length on the limit critical uniformly distributed load are also discussed.
Deflection of Castellated Beams Subjected to Uniformly Distributed Transverse Loading
Wei-bin Yuan,Nan-ting Yu,Zhao-shui Bao,Li-ping Wu 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.3
This paper presents an analytical solution for determining the deflection of castellated/cellular beams with hexagonal/circular web openings, subjected to a uniformly distributed transverse load. The solution is derived using the principle of minimum potential energy. To validate the derived analytical solution, three-dimensional linear finite element analysis is performed using four-node shell elements built-in ANSYS software. Good agreement between the finite element result and the present analytical solution is demonstrated.
( Yuan Liu ),( Jian Wang ),( Yang Liu ),( Liting Yang ),( Xuran Zhu ),( Wei Wang ),( Jiaxiao Zhang ),( Dong Wei ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.9
β<sub>2</sub>-adrenergic receptor (β<sub>2</sub>-AR) was expressed efficiently using Bac-to-Bac Baculovirus Expression System in Sf9 cells as a bio-recognition element for multianalyte screening of β-agonist residues in pork. Sf9 cells were selected as the expression system, and codon optimization of wild-type nucleic acid sequence and time-dependent screening of expression conditions were then carried out for enhancing expression level and biological activity. Under optimum conditions of multiplicity of infection (MOI) = 5 and 48 h post transfection, the protein yield was up to 1.23 mg/ml. After purification by chromatographic techniques, the purified recombinant protein was applied to develop a direct competitive enzyme-linked receptor assay (ELRA) and the efficiency and reliability of the assay was determined. The IC50 values of clenbuterol, salbutamol, and ractopamine were 28.36, 50.70, and 59.57 μg/l, and clenbuterol showed 47.61% and 55.94% cross-reactivities with ractopamine and salbutamol, respectively. The limit of detection (LOD) was 3.2 μg/l and the relevant recoveries in pork samples were in the range of 73.0-91.2%, 69.4-84.6%, and 63.7-80.2%, respectively. The results showed that it had better performance compared with other present nonradioactive receptor-based assays, indicating that the genetically modified β<sub>2</sub>-AR would have great application potential in detection of β-agonist residues.
Wei Zhou,Zhi-yuan Wei,Guang-fei Wang,Kang-ning Han,Ran Liu,Lian-Hua Ma 한국섬유공학회 2021 Fibers and polymers Vol.22 No.4
Accurate characterisation of transverse tensile deformation and damage evolution is of importance for evaluatingthe failure behaviors of three-dimensional (3D) braided composites. In the present study, a finite element method (FEM) andseveral non-destructive testing methods including acoustic emission, digital image correlation, and infrared thermography aredeveloped to investigate the transverse tensile deformation and damage evolution of 3D five-directional braided composites. In the finite element approach, a matrix-impregnated fiber bundles (MIFB) model and a representative volume cell (RVC)model, which take into account the fiber bundles and matrix, are respectively established to predict the effective mechanicalproperties of fiber bundles and simulate the deformation and progressive damage of such composites. The damaged locationsand the failure modes including matrix crack, fiber debonding and shear fracture of fiber are predicted and verified byexperimental tests. The non-destructive tests show that the transverse tensile fracture process can be divided into four stageswhich correspond to acoustic emission signals severally. The combination of the FEM based numerical modeling andmultiple non-destructive characterisation methods can accurately monitor the deformation and damage behaviors of 3Dbraided composites under transverse tensile loads and thus provide a reference for structural health monitoring of compositesin practical application.