Primary Study on the Anatomical Construction and Physical-Mechanical-Properties of Introduced Dalbergia sissoo

2011 ◽  
Vol 179-180 ◽  
pp. 1446-1452
Author(s):  
Lei Shi ◽  
Qing Feng Sun ◽  
Jiang Deng

This paper studies the anatomical construction and physical-mechanical properties of Dalbergia sissoo Roxb introduced from Nepal planting in Yuan Jiang in Yunnan Province. Results indicated: Dalbergia sissoo is diffuse-porous wood and the form of its fiber is even with an average length of 1.43mm。The micro fibril angle is 12.24°.The air-dried and profile density are respectively 0.746 g/cm3 and 0.634 g/cm3, which are normal. The air-dried and oven-dried of variance shrinkage are 1.75 and 1.55 respectively. The comprehensive quality coefficient of Dalbergia sissoo is 2309×105 Pa, which is a high quality wood for higher level material. The comprehensive study shows that human breeding Dalbergia sissoo owns elevating quality.

2012 ◽  
Vol 628 ◽  
pp. 482-485
Author(s):  
Yulia A. Lukina ◽  
Andrey V. Stepanov ◽  
Evgeny N. Bobrov

The paper deals with manufacturing technology for the forged rolls and sleeves from adamite steel at Electrostal Plant of Heavy Machinery (JSC «EZTM»). The influence of different heat treatments on microstructure and mechanical properties of the level of adamite steel is presented.


2018 ◽  
Vol 33 (4) ◽  
pp. 435-450 ◽  
Author(s):  
Patrycja Bazan ◽  
Stanisław Kuciel ◽  
Mariola Sądej

The work has evaluated the possibility of the potential reinforcing of poly(oxymethylene) (POM) by basalt fibers (BFs) and influence of BFs addition on thermal properties. Two types of composites were produced by injection molding. There were 20 and 40 wt% long BFs content with an average length of 1 mm. The samples were made without using a compatibilizer. In the experimental part, the basic mechanical properties (tensile strength, modulus of elasticity, strain at break, flexural modulus, flexural strength, and deflection at 3.5% strain) of composites based on POM were determined. Tensile properties were also evaluated at three temperatures −20°C, 20°C, and 80°C. The density and Charpy impact of the produced composites were also examined. The influence of water absorption on mechanical properties was investigated. Thermal properties were conducted by the differential scanning calorimetry, thermal gravimetric analysis, and fourier transform infrared (FTIR)-attenuation total reflection (ATR) spectroscopy analysis. In order to make reference to the effects of reinforcement and determine the structure characteristics, scanning electron microscopy images were taken. The addition of 20 and 40 wt% by weight of fibers increases the strength and the stiffness of such composites by more than 30–70% in the range scale of temperature. Manufactured composites show higher thermal and dimensional stability in relation to neat POM.


2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Przemysław Marcin Pikiński ◽  
Jaroslav Szaban ◽  
Gerda Šilingienė ◽  
Robert Korzeniewicz ◽  
Witold Pazdrowski

The aim of this study was to assess the quality of Scots pine (Pinus sylvestris L.) wood depending on the age of trees, forest site conditions and social class of tree position in the stand. Analyses were based on the determination of specific density and static bending strength, as well as the strength quality coefficient. It was to determine changes in physical and mechanical properties of timber depending on tree age as well as growth conditions reflected in the forest site such as fresh mixed coniferous forests and fresh mixed broadleaved forests. Experimental plots were established in 6 localities with 30, 40 and 60-year-old trees. In each of the stands, a 1-hectare experimental plot was established. Based on the measured DBH and tree height, dimensions of three mean sample trees were calculated, while the classification of social class of tree position in the stand developed by Kraft (1884) was also applied. Analyses were conducted on wood samples with 12% moisture content. Strength tests on wood samples were performed on an Instron 33RH204 universal strength testing machine. A detailed analysis showed properties of pine wood are improved with an increase of tree age in both forest sites. Statistically significant differences were observed for wood density and static bending strength. More advantageous properties were observed for wood of pines from the less fertile forest site, i.e., fresh mixed coniferous forests. Density and static bending strength were markedly determined by tree age and growth conditions. The static bending strength quality coefficient from pines growing in the fresh mixed coniferous forests increased between 30 and 40 years, similarly as it was for the fresh mixed broadleaved forests, while between 40 and 60 years, it deteriorated for the fresh mixed coniferous forests. Wood density from the fresh mixed coniferous forests was by 3% to 7% greater than pines growing in fresh mixed broadleaved forests. In turn, static bending strength of wood from pines growing in fresh mixed coniferous forests was by 4% to 10% greater than trees from the fresh mixed broadleaved forests.  Keywords: Scots pine, wood properties, forest site, Poland


2021 ◽  
Author(s):  
Somayeh Asgary ◽  
Amir Hoshang Ramezani ◽  
Zhaleh Ebrahimi Nejad

Abstract WS2 flakes have been grown successfully on SiO2 substrate via chemical vapor (CVD) deposition method by reduction and sulfurization of WO3 using Ar/ H2 gas and sulfur evaporated from solid sulfur powder. The prepared samples were characterized by optical microscopy (OM), atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman spectra and photoluminescence (PL). Large domain WS2 monolayers are obtained by extending the growth time. The perfect triangular single-crystalline WS2 flakes with an average length of more than 35 µm were achieved. The sharp PL peak (∼1.98 eV) and two distinct Raman peaks (E2g and A1g) with a ∼ 71.5 cm-1 peak split indicating that relatively high quality WS2 crystals with a regular triangle shape can be synthesized. Higher growth time shows larger triangular-shaped of WS2.


2020 ◽  
Vol 182 ◽  
pp. 109794
Author(s):  
Babak Azizi ◽  
Sasan Rezaee ◽  
Mohammad Jafar Hadianfard ◽  
Kianoush Hatami Dehnou

2019 ◽  
Vol 29 (4) ◽  
pp. 384-389 ◽  
Author(s):  
Yanpeng Yang ◽  
Yunjie Ping ◽  
Youning Gong ◽  
Zhongchi Wang ◽  
Qiang Fu ◽  
...  

2013 ◽  
Vol 2 (6) ◽  
pp. 24
Author(s):  
A. S. Oyerinde ◽  
A. P. Olalusi

<p>The effect of moisture content on some physical and mechanical properties of two varieties of tigernuts (<em>Cyperus esculentus</em>) was investigated. These properties include: geometric dimensions, linear dimensions, 1000 tuber weight, bulk density, tuber size, sphericity, angle of repose, porosity, coefficient of static friction and compressive strength. The moisture content levels used were 20, 25, 30, 35 and 40% wet basis (wb), and the two tigernut varieties used were yellow and brown types. The linear dimension, geometric diameter, sphericity, 1000- tuber weight, bulk density and angle of repose in both varieties increased with increasing moisture content. The average length, width and thickness of the yellow variety increases more than the brown variety at the determined moisture contents. True density of the yellow variety increased while the brown variety decreased with increase in moisture content. The porosity of the yellow variety reduces with increase in moisture content from 45.95 at 20% mc to 42.4 at 40% mc, while the brown variety decreased from 42.72 at 20% mc to 30.77 at 40% moisture content. The yellow variety had bigger size tubers than the brown variety and this has serious implications in packing, handling and transportation issues.</p>


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