• Title/Summary/Keyword: properties changes

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Physicochemical Properties of Soybeans as Influenced by Storage Temperatures (저장온도가 콩의 이화학적 특성에 미치는 영향)

  • 육홍선;설민숙;이현자
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.5
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    • pp.827-832
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    • 1998
  • Soybeans(Hwangkeum Kong) were stored at 5$^{\circ}C$, $25^{\circ}C$ and 35$^{\circ}C$ for 8 months to investigate the changes of the physicochemical properties. Less physicochemical changes were detected in the soybeans stored at 5$^{\circ}C$ than those stored at $25^{\circ}C$ and 35$^{\circ}C$. High temperature and long term storage caused a decrease in the nitrogen solubility index, whereas increases in acid value and organic acid content were detected. As the storage period was extended at high temperatues, the content of unsaturated fatty acids decreased, but the content of saturated fatty acids increased. Decoloration of soybeans was clearly recognized under high temperatures. The water soluble compoents such as total solids, nitrogen and reducing sugar during water-soaking at 2$0^{\circ}C$ for 16hrs were appreciably eluted from the soybeans stored for 8 months at high temperatures. The pH of the water extract slightly shifted to the acidic range.

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A study on magnetic layer thickness effects on magnetic properties of CoCrPt/Ti perpendicular media.

  • M. S. Hwang;Lee, T. D.
    • Proceedings of the Korean Magnestics Society Conference
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    • 2000.09a
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    • pp.369-376
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    • 2000
  • Change of magnetic properties in CoCrPt/Ti perpendicular media with varying CoCrPt films thickness has been studied. As CoCrPt films thickness increase, the Ms(magnetization saturation) drastically increases at thinner thickness and gradually increases with further increase in thickness from 25nm. This Ms behaviour is associated with primarily the formation of "amorphous-like" reacted layer by intermixing of CoCrPt and Ti at CoCrPt/Ti interface and secondarily change of Cr segregation mode with varying the CoCrPt films thickness. Magnetic domain structure distinctively changes with increasing CoCrPt magnetic layer(ML) thickness. Also the strength of exchange coupling measured from the slope in demagnetizing region in M-H loop changes with ML thickness. Details of the above magnetic properties will be discussed. The expansion of lattice parameters a and c at thinner thickness suggests that Cr segregation mode may be connected with the residual stress of the films. Finally, negative nucleation field(Hn) behaviour with the exchange slope will be reported.

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Magneto-optical and optical properties of Fe-Au alloy films in a wide composition range

  • Hyun, Y.H.;Kim, C.O.;Lee, Y.P.;Kudryavtsev, Y.V.;Gontarz, R.;Kim, K.W.
    • Journal of Korean Vacuum Science & Technology
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    • v.5 no.2
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    • pp.43-46
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    • 2001
  • Fe-Au alloys are characterized by the complete solubility, and exhibit an fcc-bcc structural transformation at the Fe-rich side. The magneto-optical(equatorial Ken effect : EKE) and optical properties of Fe$\_$1-x/Aux (0 < x < 1) were investigated in the 0.5 - 5.0 eV energy range. The x-ray diffraction study shows the structural fcc-bcc transformation about 80 at. % of Fe. Noticeable changes in the optical properties caused by the fcc-bcc structural transformation was observed. The shape and intensity of the EKE spectra as well as the field dependence of the magneto-optical response were also significantly changed. It is thought that these changes are mainly comes from the induced magnetic moment in Au(and/or the emhanced magnetic moment of Fe). The nature of the prominent structure observed in the UV range of the magneto-optical Ken effect of Au/Fe multilayered films are disscussed in connection with the above results.

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Effects of Material Properties and Fabric Structure Characteristics of Graduated Compression Stockings (GCS) on the Skin Pressure Distributions

  • Liu Rong;Kwok Yi-Lin;Li Yi;Lao Terence-T;Zhang Xin
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.322-331
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    • 2005
  • Graduated compression stockings (GCS) have been widely used for the prophylaxis and treatment of venous diseases. Their gradient pressure function largely related to their fabric structure and material properties. By combing fabric physical testing and wear trials, this study investigated the GCSs fabric structure and material properties at different locations along the stocking hoses, and quantitatively analyzed the effects of fabrics on skin pressure longitudinal and transverse distributions. We concluded that, Structural characteristics and material properties of stocking fabrics were not uniform along the hoses, but a gradual variation from ankle to thigh regions, which significantly influenced the corresponding skin pressure gradient distributions; Tensile (WT, EM) and shearing properties (G) generated most significant differences among ankle, knee and thigh regions along the stocking hose, which significantly influenced the skin pressure lognitudinal gradient distribution. More material indices generating significant gradual changes occurred in the fabric wale direction along stocking hose, meaning that materials properties in wale direction would exert more important impact on the skin pressure gradient performances. And, the greater tensibility and smoother surface of fabric in wale direction would contribute to put stocking on and off, and facilitate wearers' leg extension-flexion movements. The indices of WT and EM of stocking fabrics in series A have strong linear correlations with skin pressure lognitudinal distribution, which largely related to their better performances in gradual changes of material properties. Skin pressure applied by fabric with same material properties produced pronounced differences among four different directions around certain cross-sections of human leg, especially at the ankle region; and, the skin pressure magnitudes at ankle region were more easily influenced by the materials properties, which were considered to be largely related to the anatomic structure of human leg.

Soil properties of barrier island habitats in the Nakdong river estuary (낙동강 하구 주요 사주 서식지 토양 특성)

  • Yi, Yong Min;Yeo, Un Sang;Sung, Kijune
    • Journal of Wetlands Research
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    • v.16 no.3
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    • pp.355-362
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    • 2014
  • Changes of soil properties due to sedimentation and erosion in the river estuary may lead changes in environmental factors that affect plant growth and distribution, Then habitats in the river estuary that provide various ecological functions can also be influenced. Topsoil samples were analyzed in order to understand the soil properties of important barrier islands and habitat types in the Nakdong river estuary. The samples were obtained from Phragmites communis and Scirpus planiculmis habitats, the tidal flats in the southern area of Eulsukdo, and in Mangeummerydeung, Baekhapdeung, and Doyodeung. Analyses results showed that bulk density, pH, organic matter content and total nitrogen concentration which were directly or indirectly affected by vegetation showed significant difference (p<0.05) with habitat types but no differences in water content and oxidation reduction potential which could be affected by soil texture and showed significant difference among barrier islands. Results suggested that soil properties on barrier islands in the Nakdong river estuary were influenced first by geomorphic changes due to sedimentation and erosion, and then by the presence or type of vegetation. A range of physical and chemical properties were analyzed; soil water content and bulk density (physical properties), and organic content and pH (chemical properties) were correlated with seven other soil properties, at a level of significance higher than 90%. These aspects played an important role in determining overall soil properties in the studied area.

The Effect of Alkali Treatment on the Hand of Polyester Fabrics (폴리에스테르 직물의 알칼리 감량가공에 따른 촉감의 변화)

  • 신혜원
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.5
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    • pp.783-791
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    • 1996
  • The effect of alkali treatment on the changes in characteristics, mechanical properties, and hand of polyester fabrics was studied. Two kinds of fabrics having different yarn deniers were treated varying weight loss. The results were as follows; 1. Changes in constructional characteristics by alkali treatment were: a decrease in weight & thickness of fabric, a decrease in yarn denier, a decrease in apparent density of fabric, an increase in porosity to air, and a change fiber surface. 2. As for the changes in mechanical properties by alkali treatment, findings were : an increase in WT, RT, MIU, LC, and WC, a decrease in LT, B,2HB, G,2HG,2HGS, MMD, SMD, and RC, ana an increase in drape. 3. Changes in hand by alkali treatment were: a decrease in KOSHI and HARE, an increase in FUUURAMI, SHARI, KISHIMI, and SHENAYAUASA, and an increase in T.H.V 4. In the case of the same weight loss, the hand of 40/24 fabric being composed of thinner yarns was better than the hand of 50/24 fabric. 5. When 50/24 fabric was treated to have the same weight with 40/24 fabric, so the yam deniers of two fabrics were the same, the hand of 50/24 fabric having larger weight loss was better than the hand of 40/24 fabric.

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Property Enhancement of SiR-EPDM Blend Using Electron Beam Irradiation

  • Deepalaxmi, R.;Rajini, V.
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.984-990
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    • 2014
  • Polymers are the most commonly used di-electrics because of their reliability, availability, ease of fabrication and cost. The commercial and industrial demand for advanced polymeric materials which are capable of being used in harsh environment is need of the hour. The study of the effect of electron beam irradiation on polymeric materials is an area of rapidly increasing interest. This paper discusses the resultant beneficial effects of electron beam irradiation on the SiR-EPDM blend having 50:50 composition. The changes in mechanical and electrical properties of SiR-EPDM blend which are exposed to three different doses of electron beam radiation namely 5 Mrad, 15 Mrad and 25 Mrad are presented. The irradiated blends are analyzed for their electro-mechanical and physico chemical properties. The electrical changes induced by irradiation are investigated by arc resistance, surface resistivity and volume resistivity measurements as per ASTM standards. The mechanical changes are observed by the measurement of tensile strength and elongation at break. Physico chemical investigation has been done using the FTIR, in order to investigate the irradiation induced chemical changes.

Epoxy-Based Siloxane/Silica Composites for Electronic Packaging by Composition and Molecular Structure of Siloxane, and Analysis of Changes in Properties (조성 및 실록산 분자 구조에 따른 전자 패키징용 에폭시 기반 실록산/실리카 복합체의 물성 변화 분석)

  • Junho Jang;Dong Jun Kang;Hyeon-Gyun Im
    • Journal of Powder Materials
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    • v.30 no.4
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    • pp.346-355
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    • 2023
  • Epoxy-based composites find extensive application in electronic packaging due to their excellent processability and insulation properties. However, conventional epoxy-based polymers exhibit limitations in terms of thermal properties and insulation performance. In this study, we develop epoxy-based siloxane/silica composites that enhance the thermal, mechanical, and insulating properties of epoxy resins. This is achieved by employing a sol-gel-synthesized siloxane hybrid and spherical fused silica particles. Herein, we fabricate two types of epoxy-based siloxane/silica composites with different siloxane molecular structures (branched and linear siloxane networks) and investigate the changes in their properties for different compositions (with or without silica particles) and siloxane structures. The presence of a branched siloxane structure results in hardness and low insulating properties, while a linear siloxane structure yields softness and highly insulating properties. Both types of epoxy-based siloxane/silica composites exhibit high thermal stability and low thermal expansion. These properties are considerably improved by incorporating silica particles. We expect that our developed epoxy-based composites to hold significant potential as advanced electronic packaging materials, offering high-performance and robustness.

The Effect of Combined Suboccipitalis Release Exercise and Therapeutic Ultrasound on Mechanical Properties of Cervical Muscles and Neck Disability Index, Headache Impact Test in Tension-Type Headache Patients (초음파치료를 동반한 뒤통수밑근 이완운동이 긴장성 두통 환자의 근육의 기계적인 특성과 목 장애 지수, 두통 영향 검사에 미치는 영향)

  • Park, Seung-Kyu;Park, Sam-Heon
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.4
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    • pp.271-281
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    • 2021
  • Purpose : This study aimed to apply muscle relaxation exercise and ultrasound therapy as an effective treatment method for tension headache patients by comparatively analyzing the muscle mechanical properties, neck disorder index, and headache impact test. Method : The subjects were classified into three groups based on the intervention received: the therapeutic ultrasound (n=15, group I), placebo therapeutic ultrasound combined with the suboccipital release (n=15, group II), and therapeutic ultrasound combined with suboccipital release (n=15, group III) groups. The intragroup and intergroup differences in muscle mechanical properties, neck disability index, and headache impact test were compared and analyzed. Result : The comparison and analyses of the changes in muscle tone and post hoc analysis revealed statistically significant intragroup decreases in the suboccipitalis and upper trapezius in groups I and III. Furthermore, statistically significant intergroup differences in the upper trapezius with a greater change in group III than in group II and suboccipitalis with greater changes in group III than in groups I and II were observed. The comparison and analyses of the changes in muscle stiffness and post hoc analysis revealed statistically significant intragroup decreases in the upper trapezius in group I and suboccipitalis in group III. Moreover, statistically significant intergroup differences in both muscles with greater changes in group III than in group II for both cases were observed. The comparison and analyses of the changes in the neck disability index and post hoc analysis revealed statistically significant intragroup decreases in all three groups and statistically significant intergroup differences with greater changes in group III than in groups I and II. The comparison and analyses of the changes in the headache impact test and post hoc analysis revealed statistically significant intragroup decreases in all three groups and a statistically significant intergroup difference with greater changes in group III than in groups I and II. Conclusion : The therapeutic ultrasound and suboccipital muscle release exercise effectively increased the flexibility of the muscles around the cervical vertebrae and reduced muscle tension and stiffness in tension-type headache patients.