• Title/Summary/Keyword: physical properties

Search Result 10,072, Processing Time 0.039 seconds

The Calculation of Physical Properties of Amino Acids Using Molecular Modeling Techniques (II)

  • Lee, Myung-Jae;Kim, Ui-Rak
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.7
    • /
    • pp.1046-1050
    • /
    • 2004
  • Six physical properties (enthalpy, density, decomposition temperature, solubility in water, pKa values, and hydronium potential) were examined by molecular modeling techniques. The molecular connectivity index, Wiener distance index, and Ad hoc descriptor are employed as structural parameters to encode information about branching, size, cyclization, unsaturation, heteroatom content, and polarizability. This paper examines the correlation of the molecular modeling techniques parameters and the physicochemical properties of amino acids. As a results, calculated values were in agreement with experimental data in the above six physical properties of amino acids and the molecular connectivity index was superior to the other indices in fitting the calculated data.

A Study on Thermo-Physical Properties of Microencapsulated Phase Change Material Slurry (마이크로캡슐 잠열 축열재 혼합수의 열물성에 관한 연구)

  • 임재근;최순열;김명준
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.28 no.6
    • /
    • pp.962-971
    • /
    • 2004
  • This paper has dealt with thermo-physical properties of microencapsulated phase change material slurry as a latent heat storage material having a low melting point. The measured results of the thermo-physical properties of the test microencapsulated phase change material slurry, those are, density, specific heat, thermal conductivity and viscosity, were discussed for the temperature region of solid and liquid phases of the dispersion material (paraffin). The measurements of these properties of microencapsulated phase change material slurry have been carried out by using a specific-gravity meter, a water calorimeter, a differential scanning calorimeter(DSC), a transient hot wire method and rotating type viscometer, respectively. It was clarified that the additional properties law could be applied to the estimation of the density and specific heat of microencapsulated phase change material slurry and also the Euckens equation could be applied to the estimation of the thermal conductivity of this slurry.

Analysis on the Physical Property of Nylon High Tenacity Coarse Yarn and Fabric for Military and Technical Textiles (군용 및 산자용 나일론 고강력 태섬사 및 후직물의 물성 분석)

  • Kim, Seung-Jin;Kim, Sang-Ryong;Lee, Do-Hyun;Choi, Woo-Hyuk
    • Textile Coloration and Finishing
    • /
    • v.21 no.3
    • /
    • pp.43-48
    • /
    • 2009
  • This paper surveys the mechanical properties of nylon high tenacity coarse yarn and fabric for military and technical textiles. For this purpose, 6 kinds of yarns and 2 kinds of fabrics are prepared. The yarn physical properties such as yarn count, thermal shrinkages, and tensile properties are measured and discussed with the characteristics of the domestic and imported yarns. And, the physical and mechanical properties of these fabrics are also measured and discussed with the usage of these fabrics in the military and technical textiles fields. Hereafter, the differences of physical properties between domestic and foreign yarn specimens for high functional military and technical fabrics are estimated through this study.

Physical Characteristics of Small Space Objects at High Orbits Based on Optical Methods

  • El-Hameed, Afaf M. Abd;Attia, Gamal F.;Abdel-Aziz, Yehia
    • Journal of Astronomy and Space Sciences
    • /
    • v.34 no.1
    • /
    • pp.31-35
    • /
    • 2017
  • Optical observation is one of the most common techniques used for characterizing the physical properties of unknown objects and debris in space. This research presents measurements and properties of the new object 96019 from ground-based optical methods. Optical observations of this small object were performed using a charge-coupled device (CCD) camera and the Santel-500 telescope at the Zvenigorod Observatory. The orbital elements and physical properties of this object, such as area-to-mass ratio, have been determined. The results show that this small object has a low area-to-mass ratio, between 0.009 and $0.12m^2/kg$. The light curve of object 96019 is given: Over the time intervals, variations in brightness are analyzed and the maximum brightness was found to be 12.4 magnitudes. The observational results show that, this object brightens by about three magnitudes over a time span of three minutes. Based on these observations, the characteristics and physical properties of this object are discussed.

Physical Properties and Optimization of Tangsuyuk Batter Ingredients (탕수육 배터의 물리적 특성 및 최적화)

  • 이현규;이경숙;양차범;양지영;이재우;박관화
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.28 no.6
    • /
    • pp.1260-1268
    • /
    • 1999
  • Physical properties were investigated in tangsuyuk batter containing different amounts of ingredients, such as wheat flour, corn starch, sodium bicarbonate, alum and water. For the response surface methodology (RSM) central composite design was used to determine the optimal ingredient ratios for viscosity, color properties(lightness, redness, yellowness, color differences) and cutting forces. There were significant differences(p<0.05) between the different batter mixtures. The lightness(L) of batter was in proportion to the increased amount of wheat flour and corn starch. Higher redness was recorded with increasing corn starch. Higher yellowness was observed with increasing wheat flour and sodium bicarbonate. Color differences were higher with increasing wheat flour, corn starch, and/or alum and decreasing water. Cutting forces were linearly increased with increasing sodium bicarbonate. From these results, it is possible to monitor the effects of ingredients on physical properties of tangsuyuk batter, and to predict their optimal ratios.

  • PDF

The Study on the Properties of EPDM/NR Blends (EPDM/NR 블랜드의 물성에 관한 연구)

  • Go, Jin-Hwan;Park, Sung-Soo
    • Elastomers and Composites
    • /
    • v.29 no.2
    • /
    • pp.121-130
    • /
    • 1994
  • The physical properties of rubber blend between natural rubber(NR) and ethylene propylene diene terpolymer(EPDM) were investigated as a study of EPDM composite materials. For EPDM/NR blends, the effects of ethylene and diene contents in EPDM, blend ratio, dicumyl peroxide(DCP) curing system on the physical properties, interfacial adhesion force and dynamic crack growth etc. were studied. EPDM/NR blends loaded with carbon black were prepared by mechanical mixing and cured by plate heating cure press. Crosslinking density was measured by swelling method with toluene. The physical properties of all blends were measured with Instron, fatigue to failure(FTF), Demattia flex cracking tester(DMFC), scanning electron microscopy (SEM), etc. As the ethylene and diene contents in EPDM increased, the physical properties, such as dynamic crack growth, adhesion to other component were increased too. Interfacial adhesion force of EPDM/NR blends to dissimilar layer was improved by the use of optimum peroxide curing system.

  • PDF

Prediction of the mechanical properties of granites under tension using DM techniques

  • Martins, Francisco F.;Vasconcelos, Graca;Miranda, Tiago
    • Geomechanics and Engineering
    • /
    • v.15 no.1
    • /
    • pp.631-643
    • /
    • 2018
  • The estimation of the strength and other mechanical parameters characterizing the tensile behavior of granites can play an important role in civil engineering tasks such as design, construction, rehabilitation and repair of existing structures. The purpose of this paper is to apply data mining techniques, such as multiple regression (MR), artificial neural networks (ANN) and support vector machines (SVM) to estimate the mechanical properties of granites. In a first phase, the mechanical parameters defining the complete tensile behavior are estimated based on the tensile strength. In a second phase, the estimation of the mechanical properties is carried out from different combination of the physical properties (ultrasonic pulse velocity, porosity and density). It was observed that the estimation of the mechanical properties can be optimized by combining different physical properties. Besides, it was seen that artificial neural networks and support vector machines performed better than multiple regression model.

The Effect of Pile Length on the Handle and Physical Properties of Velvet (Velvet의 pile 길이가 촉감 및 물리적 특성에 미치는 영향)

  • 장정애;류덕환
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.19 no.3
    • /
    • pp.471-482
    • /
    • 1995
  • Using the acetate velvet and viscose velvet whose pile lengths were sheared as 1.45, 1.55, 1 65, 1.75, 1.85, 1.90mm under the condition equating the weaving process of ground fabric, the conclusions were as follows through the results of the sensory assessments estimated by women students in our university and the physical properties, H. V and T. H. V obtained by KES-F system. 1. In the sensory assessments estimated by the method of paired comparison and ranking of samples, the longer pile length was, the more the hand values of smoothness, softness, thickness, heaviness increased on the whole. 2. The H V. and T. H. V. measured by KES-F system were as follows; Kohi increased to pile length 1.85mm and then decreased a little at 1.90mm. hummer increased as pile length was longer. Fukurami increased to pile length 1.75mm and then decreased gradually as pile length was longer. Total hand value increased gradually from 1. 45mm to 1.85mm, had the top value at 1.85mm, and then decreased a little at 1.90mm. 3. In the results of summarizing $\ulcorner$the physical properties correlated closely with the H. V obtained by sensory assessments$\lrcorner$ and tithe Physical properties correlated closely with the H. V. and T. H. V obtained by KES-F systems, it showed that all the sensory properties correlated closely with compressive energy, flexural rigidity, thickness, weight and pile ratio in the former and that the physical properties correlated closely with each H V and T. H. V were different in the latter. 4. It showed that factor 1 was related to compressive energy, thickness, weight, pile ratio, factor 2 was related to recovery energy, compressive resilience, compressive index, and factor 3 was related to compressive recovery ratio in the result of factor analysis. 5. In the multiple repression analysis, the expressions of all sensory properties had compressive ratio, frictional coefficient in the regression expressions of $\ulcorner$H. V. obtained by sensory assessments$\lrcorner$, while the expressions of each H. V. and different physical properties in the regression expressions of $\ulcorner$H. V. obtained by KES-F system$\lrcorner$.

  • PDF

Physical and Mechanical Properties of Local Styrax Woods from North Tapanuli in Indonesia

  • Iswanto, Apri Heri;Susilowati, Arida;Azhar, Irawati;Riswan, Riswan;Supriyanto, Supriyanto;Tarigan, Joel Elpinta;Fatriasari, Widya
    • Journal of the Korean Wood Science and Technology
    • /
    • v.44 no.4
    • /
    • pp.539-550
    • /
    • 2016
  • The objective of this research was to evaluate physical and mechanical properties of three species of Styrax woods from North Tapanuli in Indonesia. The woods were more than 15 years old. Physical properties such as specific gravity, green moisture content, and volume shrinkage were determined by the procedures based on BS-373 standard for small clear specimen. Furthermore, mechanical properties, including modulus of rupture, modulus of elasticity, compression parallel to grain and hardness were also tested according to the standard. Along the stem direction, the edge section had better properties compared with those near the pith section. And the base section had also better properties than upper section. Based on the specific gravity, all of the Styrax woods in this research were classified into III-IV strength classes. A good dimensional stability was demonstrated by the value of the tangential and radial ratio which reached one. With the consideration of the mechanical properties, Styrax woods were suitable use for raw materials of light construction, furniture and handy craft.

Effect of Filler Addition on Properties of Sheets Prepared from Bacterial Cellulose (박테리아 셀룰로오스 시트의 물성에 미치는 충전제의 첨가효과)

  • 조남석;민두식
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.30 no.4
    • /
    • pp.35-41
    • /
    • 1998
  • The bacterial cellulose has many unique properties that are potentially and commercially beneficial. In order to make opaque product from this cellulose, filling properties by fillers should be known. This study was performed to investigate the effect of filler addition on physical properties of sheets from bacterial cellulose. The effect of filling on its optical properties was also discussed. The apparent density and internal bonding strength of bacterial cellulose sheet are decreasing with the increase of filler contents. Those adversely affect Young's modulus and physical property of the sheet, but these negative phenomena of the bacterial cellulose sheet by filler addition are not so sensitive compared to substantial decreasing of physical properties of ordinary hardwood KP. This strength decrease would be attributed to the decrease of relative bonding sites among pulp fibers. Concerned to optical properties, the bacterial cellulose sheet shows high increase of brightness and opacity according to filler loading, but no significant changes in porosity up to 17.3% loading because of fine and filamentous structure of bacterial cellulose fibers.

  • PDF