• Title/Summary/Keyword: physical & mechanical properties

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Physical and Mechanical Properties of Quercus glauca Thunberg according to Forest Stand Characteristics (임분 특성에 따른 종가시나무의 물리·역학적 특성)

  • Hong, Nam-Euy;Won, Kyung-Rok;Yoo, Byung-Oh;Jung, Su-Young;Kim, Byung-Ro;Byeon, Hee-Seop
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.5
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    • pp.767-775
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    • 2016
  • Wood properties are affected by environmental factors such as soil, topography, rainfall, and climate change. The physical and mechanical properties of Quercus glauca were analyzed in order to investigate the relationship between wood properties and forest stand characteristics related to regions and forest origins. Physical and mechanical properties of wood were influenced by region. And no significant difference was observed between natural and artificial forests with respect to wood quality properties. Therefore, these findings are expected to be useful as fundamental data for silviculture practices of these species for wood quality.

Effects of Paper Sludge Addition on Formaldehyde Emission, and Physical and Mechanical Properties of UF-Particleboard (제지 슬러지의 첨가가 요소수지 파티클보드의 포름알데히드 방산 및 물리적, 기계적 성질에 미치는 영향)

  • Kim, Dae-Jun;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.1
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    • pp.44-53
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    • 1994
  • This research was carried out to investigate the effect of paper sludge addition on formaldehyde emission, and physical and mechanical properties of UF-particleboard. In order to investigate the effect of paper sludge addition to resin, particleboards were bonded with urea-formaldehyde resins containing 5, 10, 15% paper sludge powders of three types(A Type: -200 mesh, B Type: -100~+200 mesh. C Type: -50~+100 mesh), based on weight of resin solid. Also the effect of paper sludge addition to furnish was studied from particleboards fabricated with ratios of sludge to particle of 5:95, 10:90, 15:85 based on oven-dry weight. Tests were conducted on the manufactured particleboards to determine formaldehyde emission, bending properties, internal bond strength and thickness swelling. The obtained results were summarized as follows: The addition of paper sludge powder to resin yielded a higher pH of cured resin. Formaldehyde emission decreased with the increase of paper sludge powder addition to resin and paper sludge composition ratio to furnish. Particleboard bonded with urea-formaldehyde resin containing paper sludge powder and particleboard mixed with paper sludge have similar bending properties(MOR, MOE) and thickness swelling compared with control particleboard. Internal bond strength of particleboards treated with paper sludge were lower than that of control particleboard. The use of paper sludge as scavenger was achieved reduction of formaldehyde emission without depression of physical and mechanical properties of particleboard. Also the use of paper sludge was able to concluded that there is possibility of partial substitution of wood particle materials.

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Effects of Process Variables and MAPP Coupling Agent on Properties of Wood Fiber-Polypropylene Fiber Composite by Turbulent Air Mixing (공정변수(工程變數)와 MAPP 결합제(結合劑)가 난기류(亂氣流) 혼합방식(混合方式)에 의하여 제조(製造)된 목섬유(木纖維)-폴리프로필렌섬유(纖維) 복합재(複合材)의 성질(性質)에 미치는 영향(影響))

  • Yoon, Hyoung-Un;Park, Jong-Young
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.1
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    • pp.76-86
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    • 1998
  • Effects of processing variables and MAPP (maleic anhydride polypropylene) coupling agent on the properties of composite were discussed for turbulent-air-mixed woodfiber-polypropylenefiber composites. In this research, density, composition ratio, and mat moisture content were established as processing variables, and emulsified MAPP prepared by direct pressure method was incorporated as the coupling agent. And the turbulent air mixer, which was improved in function through alteration of our previous fiber mixer, was used to mix wood fibers and polypropylene fibers. At the addition level of 1% MAPP, based on oven-dried wood fiber weight, woodfiber-polypropylenefiber composites generally showed enhanced the physical and mechanical properties. And composites with low to medium densities of 0.6 to 0.8g/$cm^3$ greatly increased in these property values than with high densities of 1.0g/$cm^3$ or more by adding 1 % MAPP. Thus, MAPP addition was thought to be an effective way of enhancing properties for nonwoven web composites. At the mat moisture contents of 5 to 20%, however, the physical and mechanical properties were not enhanced by adding 1% MAPP. In the composites containing 15% polypropylene fibers, the lowest thickness swelling and water absorption values were observed at the 1% MAPP level. The addition of more than 1% MAPP had the adverse effect on the physical and mechanical properties of composites.

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A Study on Quantitative Visualization and Measurement of Physical Properties of Radial Symmetric Fluids Using Electronic Speckle Pattern Interferometry (전자 스체클 패턴 간섭법을 이용한 반경방향 대칭 유체의 정량적 가시화 및 물성치 측정에 관한 연구)

  • Gang, Yeong-Jun;Chae, Hui-Chang;Kim, Gyeong-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.2
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    • pp.217-224
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    • 2002
  • It is very important to measure and visualize the changes in the physical properties of fluid flow because this is the foundation of measurement techniques used in aerodynamics, heat transfer, plasma diagnostics, and stress analysis of transparent models. The optical methods are advantageous over probe-based techniques in the optical methods are of high speed, non-contact and are capable of providing full-field results with high spatial resolution. Therefore we propose the electronic speckle pattern interferometry(ESPI) that gives us a solution to overcome those limitations. In this paper the experimental results show qualitative and quantitative visualization of changes in the physical properties of the candle and alcohol lamp with 3D plotting. And we obtained the refractive index, mass density and temperature distribution of fluids. The results clearly show the process of flow phenomena and give the feasibility of quantitative interpretation of gasdynamics.

Physical and Chemical Properties of Silk Fiber Treated with Calcium Nitrate (질산칼슘 처리농도에 따른 수축견사의 이화학적 특성)

  • 이광길;이용우
    • Journal of Sericultural and Entomological Science
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    • v.40 no.1
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    • pp.70-77
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    • 1998
  • This study was carried out in order to find out the relationship between physical and chemical properties of silk fiber treated by concentrated calcium nitrate solution. The tensile, thermal and dynamic mechanical properties are also examined on Ca(NO3)2 treated silk fibers. The tensile properties of silk fibers treated by calcium nitrate changed with a concentration. The thermal behavior were also affected by the concentration of calcium nitrate. The degradation temperature (endotherms) and glass transition temperature shifted to lower temperature as the treated concentration increased. It is thought that the physical properties are strongly related to the structure and morphology of Ca(NO3)2 treated silk fibers. As a result, these give property changes with a concentration dependence.

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Effect of Particle Pre-Treatment on Properties of Jatropha Fruit Hulls Particleboard

  • Iswanto, Apri Heri;Febrianto, Fauzi;Hadi, Yusuf Sudo;Ruhendi, Surdiding;Hermawan, Dede;Fatriasari, Widya
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.2
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    • pp.155-165
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    • 2018
  • The objective of the research was to evaluate the effect of particle pre-treatment on physical, mechanical, and durability of jatropha fruit hulls (JFH) particleboard. The pre-treatments included were immersing in cold water, hot water, and acetic acid solution. After each treatment, the particles were dried up to 3% moisture content. Urea-formaldehyde (UF) resin was used to fabricate particleboards with board size, thickness and density target of 25 cm by 25 cm, 0.80 cm, and $0.70g/cm^3$, respectively. Board pressed at $130^{\circ}C$ for 10 minutes, and $25kg/cm^2$ pressure. The evaluation of particleboard followed the JIS A 5908-2003. Whilist their resistance to subterranean termite test (mass loss, mortality, antifeedant value and feeding rate) refers to the Indonesian standard (SNI 01.7207-2006). The physical and mechanical properties of particleboards showed that all pre-treatments decreased the pH of particles. Overall, all particle immersing treatments resulted of better physical and mechanical properties of particleboard than those of untreated ones. The acetic acid treatment resulted the best physical and mechanical properties of particleboard. Based on the mass loss of JFH particleboard, hot water and acetic acid treated particleboards were classified into weak resistance to subterranean attack. The other two treatments were classified into very weak resistance. Hot water treated particleboard provided the highest mortality and antifeedant as much as 87.40% and 34.20%, respectively. Based on antifeedant classification, hot water treated particleboards were classified into moderately strong resistance, while other treatments were categorized into weak resistance. The lowest feeding rate value ($45.30{\mu}g/termite/day$) was attained by hot water treatment.

Effect of Blast Furnace Slag, Hwang-toh and Reinforcing Fibers on The Physical and Mechanical Properties of Porous Concrete Using Blast Furnace Slag Coarse Aggregate (고로슬래그 골재를 사용한 다공성 콘크리트의 물리·역학적 특성에 미치는 고로슬래그 미분말, 황토 및 보강섬유의 효과)

  • Lee, Jin-Hyung;Park, Chan-Gi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.52 no.5
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    • pp.53-60
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    • 2010
  • The effects of blast furnace slag, hwang-toh, and reinforcing fiber on the physical and mechanical properties of porous concrete using blast furnace slag coarse aggregates have been evaluated in this study. The effect of the depending on replacement ratio of blast furnace slag to cement was investigated such that the replacement ratio was varied to 0 %, 25 % and 50 %. Also, the replacement ratios of hwang-toh were 0, 20 and 30 %. The polyvinyl alcohol fiber was used for the reinforcing fiber. A series of pH, unit mass, and void ratio tests have been performed to study the physical properties of the porous concrete using blast furnace slag coarse aggregates with the polyvinyl alcohol fiber and the replacement ratios of blast furnace slag, hwang-toh, while a series of compressive tests have been performed to evaluate the strength property depending on polyvinyl alcohol fiber and the replacement ratios of blast furnace slag, hwang-toh. The test results indicated that the physical and mechanical properties of porous concrete using blast furnace slag coarse aggregates is affected by the replacement ratio of blast furnace slag, and the fiber contents. According to the tests with polyvinyl alcohol fiber contents, the void ratio was decreased and the compressive strength was upgraded.

A study on the process technology for controlling the shape and physical properties of melt-blown non-woven (멜트블로운 부직포의 형태와 물리적 특성을 제어하는 공정기술에 관한 연구)

  • Jae-Seok Jeong;Mikyung Kim;Jung Woo Ko
    • Journal of the Korean institute of surface engineering
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    • v.56 no.5
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    • pp.309-319
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    • 2023
  • Non-woven fabric is a textile product made by spinning thermoplastic polymers without manufacturing processes such as stretching, doubling, twisting, weaving, and knitting to form a sheet-shaped web in which fibers are tangled with each other, and then combining them by mechanical and physical methods. In addition, the non-woven fabric manufacturing process has various raw material choices, high productivity, so it is a textile manufacturing technology that can have various uses and increase added value. This study was conducted to control the shape and physical properties of products by improving the manufacturing method of melt-blown non-woven fabrics using process technology that easily changes the shape of non-woven fabrics and improves mechanical properties. In particular, it is considered that a non-woven fabric with a thin material shape and improved mechanical properties will be easily applied to a continuous secondary battery manufacturing industry such as roll to roll operation.

The relation between physical/mechanical properties md ballistic properties in several engineering ceramics (세라믹스의 물리/기계적 물성과 방탄물성과의 상관관계 연구)

  • Kim Cheol-soo;Lee Hyung-Bock
    • Composites Research
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    • v.18 no.6
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    • pp.34-39
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    • 2005
  • In this study, we analyzed the relation between physical/mechanical properties and ballistic properties for several engineering ceramics that were expected to use as armor material. After physical/mechanical measurement, we measured ballistic properties about KE(Kinetic Energy, L/D=10.7, tungsten heavy alloy) and HEAT(High Explosive Anti-Tank, K215) projectiles. Increasing Young's modulus/density, hardness/density and flexural strength/density ratios, ballistic properties were generally increased. Especially it appeared that the ballistic property about KE projectile was lineally increased, as HEL/density ratio increased.

Wood Properties of Quercus acuta Thunb. (붉가시나무의 목재성질)

  • Chong, Song-Ho;Park, Byung-Su;Chung, Doo-Jin;Lee, Do-Sick;Cho, Sung-Taek;Chun, Su-Kyoung
    • Journal of the Korea Furniture Society
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    • v.18 no.1
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    • pp.39-46
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    • 2007
  • This study was carried out to investigate the wood properties for efficient utilization of warm temperate tree species of Quercus acuta Thunb. grown in Korea. Fundamental wood properties in the anatomical, physical, mechanical and chemical characteristics were examined. Quercus acuta Thunb. is a radial-porous, straight grained and fine textured wood. The heartwood is not clearly distinguished from the sapwood. In physical properties, it has a high oven-dry specific gravity of $0.85{\pm}0.02$, and high shrinkage from green to air-dried condition of $7.05{\pm}0.52%$ in radial and $11.13{\pm}0.48%$ in tangential direction. Mechanical properties determined are strong with the MOR of $1,065{\pm}90kgf/cm^2$, and tensile strength parallel to grain of $1,490{\pm}258kgf/cm^2$ and shear strength of $175{\pm}13kgf/cm^2$. Also, this wood has high extractive contents: 11.11% for cold and 13.51% for hot water.

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