Effect of ultrahigh pressure processing (UHP) on physicochemical properties, antioxidant activity and anti-inflammatory activity of insoluble dietary fiber from Pholiota nameko

Haiping Li,Xinqi Guo,Xun Zhu,Yina Chen,Limin Zhang,Jiaqi Lu,Qiuting Qian 한국식품과학회 2024 Food Science and Biotechnology Vol.33 No.2

The aim of this study was to evaluate the effect of ultrahigh pressure processing (UHP) of 200, 300, 400, 500, 600 and 700 MPa for 20, 40 and 30 min on physicochemical and bioactive properties of the insoluble dietary fiber Pholiota nameko (PN-IDF). The results revealed that UHP were capable of decreasing the particle size of PN-IDF and binding phenolic content. Moreover, UHP technique had an improving effect on the bioaccessible phenolic content, the water-holding capacity, the oil-holding capacity and the nitrite ion adsorption capacity. Further, UHP technique presented a promoting effect on the antioxidant activity by scavenging ABTS or DPPH free radicals and increasing reducing power, and the anti-inflammatory activity by inhibiting carrageenan-induced paw edema on PN-IDF. Overall, this study well proved that UHP technology could improve the physicochemical and functional quality of PN-IDF, which could be used as a promising green technique for functional food ingredients processing.

Key Characteristics of a Novel Silk Yarn from Fresh Cocoons

Qifan Xie,Haiping Zhang,Mingying Yang,Liang-Jun Zhu 한국섬유공학회 2018 Fibers and polymers Vol.19 No.1

We studied the key characteristics of a novel silk yarn reeled from fresh cocoons. Compared with traditional silk yarn, this novel silk yarn displayed better mechanical properties, especially in terms of a higher breaking stress and toughness, and exhibited a different surface morphology. A cross-sectional observation and the sericin content results illustrated that different sericin coatings on the silk yarn reeled from fresh cocoons surface did not improve the mechanical properties. The degumming and tensile testing analysis indicated that degummed silk fibroin of novel silk yarn is able to resist deformation and fracture better than silk fibroin of traditional silk yarn. The FTIR results revealed that the selected techniques is an important contributor to the silk fibroin mechanical properties, because novel technique brought higher percentage beta-sheet structures in novel silk yarn fibroin than traditional silk yarn. The new technique that using novel silkyarn has improved its mechanical properties and it is expected that the silk yarn with superior mechanical properties could be used in fabrics transistors, electrodes and reinforced biomaterials.

Nonlinear thermal buckling of bi-directional functionally graded nanobeams

Yang Gao,Wan-Shen Xiao,Haiping Zhu 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.71 No.6

We in this article study nonlinear thermal buckling of bi-directional functionally graded beams in the theoretical frameworks of nonlocal strain graded theory. To begin with, it is assumed that the effective material properties of beams vary continuously in both the thickness and width directions. Then, we utilize a higher-order shear deformation theory that includes a physical neutral surface to derive the size-dependent governing equations combining with the Hamilton’s principle and the von Kármán geometric nonlinearity. It should be pointed out that the established model, containing a nonlocal parameter and a strain gradient length scale parameter, can availably account for both the influence of nonlocal elastic stress field and the influence of strain gradient stress field. Subsequently, via using a easier group of initial asymptotic solutions, the corresponding analytical solution of thermal buckling of beams is obtained with the help of perturbation method. Finally, a parametric study is carried out in detail after validating the present analysis, especially for the effects of a nonlocal parameter, a strain gradient length scale parameter and the ratio of the two on the critical thermal buckling temperature of beams.

Nonlinear bending of functionally graded porous nanobeam subjected to multiple physical load based on nonlocal strain gradient theory

Yang Gao,Wan-Shen Xiao,Haiping Zhu 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.31 No.5

We in this paper study nonlinear bending of a functionally graded porous nanobeam subjected to multiple physical load based on the nonlocal strain gradient theory. For more reasonable analysis of nanobeams made of porous functionally graded magneto-thermo-electro-elastic materials (PFGMTEEMs), both constituent materials and the porosity appear gradient distribution in the present expression of effective material properties, which is much more suitable to the actual compared with the conventional expression of effective material properties. Besides the displacement function regarding physical neutral surface is introduced to analyze mechanical behaviors of beams made of FGMs. Then we derive nonlinear governing equations of PFGMTEEMs beams using the principle of Hamilton. To obtain analytical solutions, a two-step perturbation method is developed in nonuniform electric field and magnetic field, and then we use it to solve nonlinear equations. Finally, the analytical solutions are utilized to perform a parametric analysis, where the effect of various physical parameters on static bending deformation of nanobeams are studied in detail, such as the nonlocal parameter, strain gradient parameter, the ratio of nonlocal parameter to strain gradient parameter, porosity volume fraction, material volume fraction index, temperature, initial magnetic potentials and external electric potentials.

On axial buckling and post-buckling of geometrically imperfect single-layer graphene sheets

Yang Gao,Wan-Shen Xiao,Haiping Zhu 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.33 No.2

The main objective of this paper is to study the axial buckling and post-buckling of geometrically imperfect single-layer graphene sheets (GSs) under in-plane loading in the theoretical framework of the nonlocal strain gradient theory. To begin with, a graphene sheet is modeled by a two-dimensional plate subjected to simply supported ends, and supposed to have a small initial curvature. Then according to the Hamilton*$39;s principle, the nonlinear governing equations are derived with the aid of the classical plate theory and the von-karman nonlinearity theory. Subsequently, for providing a more accurate physical assessment with respect to the influence of respective parameters on the mechanical performances, the approximate analytical solutions are acquired via using a two-step perturbation method. Finally, the authors perform a detailed parametric study based on the solutions, including geometric imperfection, nonlocal parameters, strain gradient parameters and wave mode numbers, and then reaching a significant conclusion that both the size-dependent effect and a geometrical imperfection can't be ignored in analyzing GSs.

The Research on the Effects of Electrical Aging on Trap Distribution in Polyethylene Doped with Nanoparticies

Lijuan He,Shan Wang,Chao Zhu,Haiping Xie,Dawei Li,Chuntian Chen 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.5

Nonlinear vibration of functionally graded nano-tubes using nonlocal strain gradient theory and a two-steps perturbation method

Yang Gao,Wan-Shen Xiao,Haiping Zhu 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.69 No.2

This paper analyzes nonlinear free vibration of the circular nano-tubes made of functionally graded materials in the framework of nonlocal strain gradient theory in conjunction with a refined higher order shear deformation beam model. The effective material properties of the tube related to the change of temperature are assumed to vary along the radius of tube based on the power law. The refined beam model is introduced which not only contains transverse shear deformation but also satisfies the stress boundary conditions where shear stress cancels each other out on the inner and outer surfaces. Moreover, it can degenerate the Euler beam model, the Timoshenko beam model and the Reddy beam model. By incorporating this model with Hamilton’s principle, the nonlinear vibration equations are established. The equations, including a material length scale parameter as well as a nonlocal parameter, can describe the size-dependent in linear and nonlinear vibration of FGM nanotubes. Analytical solution is obtained by using a two-steps perturbation method. Several comparisons are performed to validate the present analysis. Eventually, the effects of various physical parameters on nonlinear and linear natural frequencies of FGM nanotubes are analyzed, such as inner radius, temperature, nonlocal parameter, strain gradient parameter, scale parameter ratio, slenderness ratio, volume indexes, different beam models.