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Study on straw liquefied product synthetizing polyurethane elastomer Shengli Zhao 1,a, Zhenhua Xue1,b , Yabin Li 1,c , Jintian Huang1,d* （Material Science and Art Designing College, Inner Mongolia Agricultural University, Hohhot 010018） a zhaoshengli11@163.com, b x_zhenhua@126.com ,c liyabin2258@163.com, d jintian_h@163.com Key words: Straw, Liquefied product, polyurethane elastomer Abstract: In order to take full advantage of straw liquefied product to make the best mechanical properties of polyurethane synthesis.
The results showed that: curing agent is 3% (1:33), the initial reaction temperature is 40 °C, curing time is 8h, the mechanical properties were the best.
The author conduct a research on corn stover liquefaction by using butanol under ordinary pressure, and analysis the impact of various factors to find the best liquefaction process which provide a theoretical basis for straw liquefaction industrial.
Test arrangement was shown in Table 1: Table1 Orthogonal Test Design Order numbers factors MOCA% Initial reaction temperature(°C) curing time (h) 1 2.0 30 6 2 2.0 40 8 3 2.0 50 10 4 2.5 30 8 5 2.5 40 10 6 2.5 50 6 7 3.0 30 10 8 3.0 40 6 9 3.0 50 8 Properties of Polyurethane Determination of mechanical properties (Reference GB/T1040-92) XRD measurement and analysis The theory of X-ray diffraction measurement method is based on the comparison between the total scattering intensity of the atoms in crystalline region and amorphous region of polymer and the scattering intensity of the atoms in crystalline region, using X-ray diffraction polyurethane elastomer powder for analysis.Voltage of XRD-6000 diffractometer: 40.0 (kV)，Divergence slit: 1.00000 (deg)，Scattering slit: 1.0000(deg)，Receiving slit: 0.30000 (mm) , Scanning range: 3.000-40.000，Scanning speed: 3.0000 (deg/min)，Sample spacing: 0.0800 (deg) Result and Analysis Mechanical Property Test Themechanical property of polyurethane
It can be perceived from figure 1, figure 2 and figure 3 that the influence of initial reaction temperature on mechanical properties is the greatest, the influence of vulcanizing time is less, and the influence of the dosage of MOCA is the least.

Previous studies [11-14] have shown that curing regimes affect the mechanical properties of MgO concrete, and constant curing temperatures in previous research have therefore been limited below 40°C despite dams existing in a variable temperature field.
A mathematical model was built to explain the differences, relevance and influencing factors of various tests under variable and constant temperature and to demonstrate how the thermostat test results apply to dams in variable temperature fields, so that reliable material properties can be provided for dam design.
Results and Discussions Mechanical Properties of Concrete under Constant-Temperature Maintenance.
Mechanical Properties of Concrete for Simulated Dam Temperature History.
Comparative Analysis of Mechanical Properties with Different Maintenance.

The properties of cement have a direct relationship with the quality of engineering structure.
The test of strength of cement is affected by many factors, such as the ratio of cement mortar, operating parameters, curing conditions, test mould and cement compression jig status [5,6].
Among the operating parameters, the factors obviously affecting cement strengths are the smooth operation, ready to face as a force, a release form and the way putting on to concrete，the factors slightly affecting cement strengths are the pilot machine to a balanced perspective, the location and the pressure test machine speed [7].
In this paper, factors affecting cement strength test are divided into two categories, which are personnel operation and apparatus.
A series of experiments were conducted for exploring the influence factors.

Research on the Stress Intensity Factor of the Crack Inclined across the Interface of Cermet Cladding Parts Junru Yang1,2 , Zhaoqian Li 3, Chuanzhen Huang3 and Quanwei Wang 1 1 College of Mechanical and Electrical Engineering, SDUST, Qingdao, China, 266510 2 School of Material Science & Engineering, Shandong University, Jinan, China, 250061 3Mechanical Engineering School, Shandong University, Jinan, China, 250061 Keywords: Cermet cladding parts, Crack inclined across the interface, Stress intensity factor Abstract.
Christina Bjerken etal [3] studied a simple method to compute plural stress intensity factor of the bi-material.
The property parameters of the two materials are in table 1.
When h1/h increases, the shear stress between the clad and the substrate increases to cause the increase of the SIF, and as the crack is inclined, the shear stress mainly affects the KIx1 and KIx2.
[7] Edit Committee of Handbook of Property Data of Materials for Mechanical Engineering: Handbook of Property Data of Materials for Mechanical Engineering (Mechanical Industry Publishing House, China 1995) (Chinese)

Introduction TWIP steels have drawn increasing attention of scientific and industrial societies in recent years due to their excellent mechanical properties particularly very high impacting energy absorption capacity generated by extremely high ductility [1-3].
The microstructures and mechanical properties were characterized for the as forged and annealed samples to understand the microstructure evolution and mechanical behavior of the samples.
Mechanical properties.
The dislocations on the grain boundaries are difficult to move and meanwhile they also impede the movement of other dislocations within the grains, leading to enhanced mechanical properties.
References [1] Grässel O, Krüger L, Frommeyer G, Meyer L W, High strength Fe-Mn-(Al, Si) TRIP/TWIP steels development - properties- application, Inter.

The validity of this method was validated through analyzing the tooth surface accuracy error of the model which was below 1µm between the virtual tooth surface and the theoretical tooth surface and the possible factors affected the tooth surface accuracy during manufacturing was also carried on the discussion.
Introduction With the development of modern industrial technology of gears, the high accuracy gear model becomes urgent need to study the mechanical properties of the gears.
Taking CATIA V5 as the modeling platform, using the macro function, through simulating the reality gear hobbing method, the whole gear hobbing simulation technology of involute helical gear was achieved, a model of high-precision gear was obtained, and the factors that may affect the accuracy of tooth surface during processing gear was also discussed.
To set up experiments to determine the influence trend of factors based on the assumed factors: hob feed speed (amount of feed after each loop) (mm/r) and interval angle of gear blank rotation (°).
[2] Li Liao: Mechanical Engineer.

By the experimental studying on the basic mechanical properties of recycled concrete hollow block masonry, the compressive and shear behavior of recycled aggregate concrete hollow block masonry under different mortar strength were analyzed.
The shear strength of the masonry was affected by the mortar strength.
The relatively systematic research on mechanical properties and structural performance of recycled aggregate concrete was conducted by many scholars at home and abroad, however the research about wall materials made with recycled concrete aggregate was less.
Specimen preparation and test methods refer to Test Methods of Basic Mechanical Properties of Masonry (GB 50129-2011).
Failure is obviously brittleness properties.

Microstructure and mechanical properties of Mo2FeB2 based cermets containing SiC whisker Haizhou Yu1, a, Wenjun Liu1, b, Lian Ying1, c, Min You1, d 1College of Mechanical and Materials Engineering, China Three Gorges University, Yichang 443002, P.
China ayu_haizhou@yahoo.cn, blwjonly1588@sina.com, cjianxiayl@sina.com, dyoumin@ctgu.edu.cn Key words: Mo2FeB2 based cermets, SiC whisker addition, Microstructure, Mechanical properties Abstract: Four series of cermets with the SiC whisker content between 0 and 1.0 wt.% were prepared by vacuum sintering.
At present, Mo2FeB2 based cermets are attracting much attention because of cheap raw material, simple preparation method and superior mechanical properties[3-4].
The effect of SiC whisker additoin on the microstructure and mechanical properties of Mo2FeB2 based cermets was studied.` Experimental procedure Commercially available Mo (4 µm), carbonyl Fe (3.5 µm), FeB (45 µm), Cr (45 µm), Ni (3 µm), C (5.5 µm) and SiC whisker powders were used as raw materials.
Thereby, it was reasonable to suggest that there were other factors that were responsible for the grain refinement in the present study.

Dangerous and harmful factors in the process of open-pit mine production and prevention countermeasures Qingmei Jia 1,a ,Weizhi Wang 1,band Ying Li 1.c 1.
At the same time, the dangerous and harmful factors existing in the process of mine production to production personnel it also caused great security hidden danger.
Affects the production and economic benefits of mining enterprises, must be control.
The chemical composition of air in the workplaces, concentration and contact time is important factors that directly determine serious to human body.
Fire, explosion, blasting damage, rooffalling slicing, collapses and landslides, floods are the serious danger and harmful factors in the mine production process.

Base metal, welded joint and HAZ (heat affected zone) materials were used to make different test specimens.
It means that welding process may lead to a great reduction in the fatigue property for titanium alloy and the effect of crack orientation on fatigue property is not negligible for titanium alloy.
Study the effect of some factors on da/dN and ΔKth of Titanium alloy are very important in engineering applications.
The chemical composition is given in table 1 and the mechanical properties in Table 2.
Table 1 Chemical Composition of Test Materials Ti Al B Fe Si C N H O Plate Rolled ring 95.57 95.64 4.0 3.975 0.005 0.005 0.23 0.215 0.05 <0.005 0.025 0.016 0.024 0.023 0.005 0.084 0.073 Table 2 Mechanical Properties of Test Materials σb [MPa] σ0.2 [MPa] δ% E [MPa] ν aKV [J/cm 2 ] Plate 682 605 18.5 1.106×105 0.34 74.9 Rolled ring 712 615 16.3 1.310×105 71.4 Table 3 Test Results of ΔKth Orientation Specimen No.