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Influence of Degumming Methods on Mechanical Properties of Silk and CODcr of Wastewater Xue Dong 1,2,a, Tieling Xing 1,2,b, Guoqiang Chen 1,2, *c 1National Engineering Laboratory for Modern Silk, Soochow University, Suzhou 215123, China 2 College of Textile and Clothing Engineering, Soochow University, Suzhou, 215006, China adongxue1126@126.com, bxingtieling@suda.edu.cn, c Corresponding author: chenguojiang@suda.edu.cn, Tel: 86 512 67162166, Fax: 86 512 67246786 Keywords: silk, degumming, structure, properties, sericin, CODcr.
Silk fibers was degummed by different methods: sodium carbonate, neutral soap, tartaric acid, 2709 alkaline proteinase and hot pressurized water.The physical properties and secondary structure of silk and the CODcr of degumming wastewater were investigated to elucidate the effects after different degumming treatment.The results showed that the silk sericin was almost removed completely through various degumming methods, the degumming effects on silk including the appearance, the mechanical properties and the CODcr of degumming wastewater were different.
It is universally acclaimed for most of the desirable properties of textile fiber: fineness, softness, smooth feeling, luster, elegance, grace and high rating.
Properties of silk fiber are greatly affected by the residual sericin.
Tensile properties are the most important factors for evaluating the performance of silk yarn for proper applications.

The main reasons for their widespread use are the provision of high rates of adhesion, mechanical and electrical insulation properties, moisture resistance and heat resistance.
Modification of the structure is associated with the formation of supramolecular formations, whose morphological characteristics depend on the conditions of structure formation and can be varied within wide enough limits, which affects the mechanical properties of polymers.
In this regard, the importance of scientific and practical importance is the study of the processes of structure formation and the study of the influence of heat treatment on the physical and mechanical properties of polymers, taking into account the scale factor [7].
Structuring large epoxy polymer products may cause structural defects that result from insufficient chemical bonding and result in a polymer with low mechanical properties.
Fang, 2018, Investigation on the mechanical properties of epoxy resin with void defects using digital image correlation and image-based finite element method, Polymer Testing 72: 223-231

Optimization Research of Mix Proportion of Frost Resistance Construction of Concrete Based on the MATLAB Language Junjie Zhang1, a, Ruihong Shao2,b , Xiangyi Meng3,c Heilongjiang university of science and technology, Heilongjiang Harbin China,150022 a120611966@qq.com, b 478980025@qq.com, c694934863@qq.com Keywords: Concrete; Freeze-thaw damage; Mix proportion; Multi-objective optimization; MATLAB fgoalattain Abstract: Analyze the influence factors of mix proportion affecting concrete freeze-thaw damage.
Because in the process of proceeding design of mix optimization according to the various properties of concrete, between the objectives and constraint conditions exist potentially conflicting relationship.
Firstly, analyze the main factors of mix proportion which influence freeze-thaw damage of concrete, and establish the functions between key performance indicators of concrete and these factors.
Factors Influencing the Mix Proportion of Concrete Freeze-thaw Damage.
According to a large number of domestic and foreign research results and engineering practice, it is proved that the main factors affecting the durability of concrete is the entrained air content of concrete, but also with the mineral admixture type, quantity, quality and concrete in the bubble properties, pore structure and other factors.

The experimental results indicate that stiffness is the main factor affecting the bending deformation.
Yarn diameter and needle geometry are another two important factors influencing the bending deformation.
As a result, yarn diameter and mechanical properties affect the curvature radius of the needle loop, further influence the plastic deformation of loop and the loop shape.
The results showed that fiber properties and the knitting parameters affect the bending deformation of stainless steel fibers.
The stiffness of fiber and the needle diameter is the most important factors.

Structural composition, physical properties and functions of tooth tissues.
Tooth Tissue Physical Properties Component Protein Cell constituents Functions Ref.
Its complex structure and properties guide the cell to differentiate into specific tissue.
A variety of growth factors have been successfully used for dentin-pulp complex regeneration, including Transforming Growth Factors (TGFs) [53], Bone morphogenetic proteins (BMPs) [54], Platelet-derived growth factor (PDGF) [55], Insulin-like growth factor (IGF) [56], Fibroblast Growth Factors (FGF), Epidermal Growth Factors (EGF) and phosphates, as discussed in Table 5.
Stem cell properties of human dental pulp stem cells, J Dent Res., 81 (2002) 531-535

The nature of natural fibers causes it to be suitable for the above said properties.
However, some properties of natural fibers may restrict its utilization.
The main problem leading to reduced mechanical properties in natural fiber reinforced polymer is the poor compatibility or adhesion between the hydrophilic fibers and the hydrophobic matrix materials.
The three factors affecting the bond between two materials are the mechanical interlocking, the molecular attractive forces, and the chemical bonds.
It is intended to improve mechanical properties by reducing moisture absorption of hydrophilic kenaf fiber [7].

In addition, the microscopic snow clearing performance, physical and mechanical properties were described and further research was proposed, which have provided a scientific basis for technology research and equipment development in the field of snow clearing.
Formation types of compacted snow-ice.The process of compacted snow-ice forming is very complicated, which is affected by external environmental factors in addition to bearing all kinds of pressure from pavement and the environmental factors can be summarized into two types below: Repeated rolling.Due to snow clearing delay or sustained snowfall, the snow on urban roads is crushed by vehicles and pedestrians repeatedly (as shown in Fig.1) , so loose snow with low density is converted to compacted snow-ice with high density, and then snow on the roads gradually forms thick ice (as shown in Fig.2).
Compacted snow-ice’s clearing performance depends on its internal structure, external temperature and other factors.
In addition, the microstructure and mechanical properties of snow-ice is hard to determine because the actual model can not added all factors to the model [7,8].
Johnson.Characterizing the microstructural and micromechanical properties of snow Cold Regions Science and Technology 30 (1999) 91–100

Mathematics Principle of Fuzzy Comprehensive Discrimination The method of comprehensive discrimination combines variety of affecting factors for evaluating the objects.
The steps are as follow: Establish factors set.
Factor set is composed of various factors of affecting the evaluation object.
The purpose of the fuzzy comprehensive evaluation is for getting appropriate evaluation result, based on the comprehensive consideration all the affect factors, from the evaluation set.
To reflect the importance of various factors, the various factors that ui should be given a corresponding weight wi.

The Volume Strain Energy Density Factor Criterion for Sharp V-notches under Mixed-mode I and II Xiaomei Liu 12*, Yongming Bian 1, Yongcheng Liang 3 1 School of Mechanical Engineering, Tongji University, Shanghai, 200092-China 2 College of Mechanical Engineering, Shanghai University of Engineering Science, Shanghai, 200062-China 3 College of Engineering Science and Technology, Shanghai Ocean University, Shanghai, 201306-China *corresponding author, email: liuxm76@163.com Keywords: V-notches, brittle fracture, volume strain energy density factor, experimental verification Abstract This paper presents a new energy approach based on the concept of a volume stain-energy-density factor useful to deal with the general problem of brittle fracture for sharp V-notches under mixed-mode I and II.
V-notch specimens and coordinate systems In this paper and , notch intensity factors for mode I and mode II , are defined as ： （3a,3b） When notch angle and , the expression (1) will be degenerated into the mixed mode crack problems.
The required material properties for PMMA were taken from [21] as elastic modulus GP poisson’s ratio strength stress MPa fracture toughness Furthermore specimens of two different notch angles for the mixed-mode of v-notch I and II were also made.
The notch intensity factors for mode I and mode II when the far field stress MPa were also taken from [21] and listed in Tab.1.
Journal of Mechanical Strength, 2008,30(2):288~292 [22] L.

Mechanical Properties and Thermal Resistance ofHigh Volume Fly Ash Concrete for Energy Efficiency in Building Construction B.
Properties studied in this research includes fresh concrete properties, mechanical properties and the resistance of concrete exposed to high temperature.
Theloss of strength at the elevated temperature is believed to be related to various factors.
One of the factors that possibly cause the deterioration is the increased moisture content of concrete.
Material and Environmental Factors Influencing the Compressive Strength of Unsealed Cement Paste and Concrete at High Temperatures.