• Title/Summary/Keyword: Swelling Ratio

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Effect of Stretching on Cellulose Fiber Swelling in Alkali Aqueous Solutions (알칼리수용액안에서 셀룰로오스섬유가 팽윤할 때 장력이 미치는 영향)

  • 최철호
    • Textile Coloration and Finishing
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    • v.4 no.3
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    • pp.91-96
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    • 1992
  • The crystalline character of NaOH and KOH-cellulose complex having different tension ratio was studied using X-ray diffraction analysis. Cellulose crystalline lattices in tension alkali treatment cotton were identified by measuring and indexing the 101, 101, and 002 reflections. According as alkali treatment tension ratio increased on, cellulose gave rise to the formation of I rather than cellulose II. It seemed that a part of the fine structure of cellulose increased orientation with antiparaell and parallel chain crystal structure. The high tension ratio alkali treatment cotton resulted in lower dye sorption and in higher breaking strength and crease recovery.

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Quality Characteristics of Sulgidduk with added Soybean Curd Residue Powder (비지분말 첨가에 의한 설기떡의 품질특성)

  • Lim, Sung-Mee;Lee, Goon-Ja
    • Korean journal of food and cookery science
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    • v.22 no.5 s.95
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    • pp.583-590
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    • 2006
  • This study was carried out to investigate the acceptable ratio of Sulgidduk with added soybean curd residue powder. The moisture content of Sulgidduk with added soybean curd residue powder (0${\sim}$ 10%) ranged from 40.54 ${\sim}$41.38%, and there were no significant differences between the addition of soybean curd residue powder and control. There were also no significant differences in swelling power and pore ratio from control to the addition of 4% soybean curd residue powder. However, these decreased with increasing addition of soybean curd residue powder of more than 6%. The L (lightness) value decreased with increasing addition of soybean curd residue powder, but the a (redness) and b (yellowness) values increased significantly. As the amount of soybean curd residue powder increased, the hardness, cohesiveness, springiness and gumminess decreased, and, the decrease was especially significant with addition of more than 6%. With increases in the storage period, the hardness, springiness and gumminess increased, while cohesiveness decreased for all additions of soybean curd residue powder. In sensory evaluations, Sulgidduk with the addition of 4% soybean curd residue powder was the most preferred with regard to overall quality. These results indicated that the Sulgidduk with 2% and 4% added soybean curd residue powder exhibited the best quality.

Evaluation of Physical Properties as Magnesium Stearate Blendedin Hydrophilic Matrix Tablets

  • Choi, Du-Hyung;Jung, Youn-Jung;Wang, Hun-Sik;Yoon, Jeong-Hyun;Jeong, Seong-Hoon
    • Journal of Pharmaceutical Investigation
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    • v.41 no.2
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    • pp.83-90
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    • 2011
  • Main objectives of this study were to investigate the effects of a lubricant, magnesium stearate, as blended in a hydrophilic matrix tablet and to identify significant factors using a tablet ejection force and a swelling property. The characteristics of tablet ejection were evaluated with three different compression forces (30, 40, and 60 MPa) and two controlled factors, amount of magnesium stearate and its mixing time. A hydrophilic model drug (terazosin HCl dihydrate) was regarded as a default factor. Tablet swelling was also evaluated. The optimal amount of PEG compared to PEO was set to be 88.50% w/w. As the amount of magnesium stearate was varied from 0.79% to 2.20% w/w, the amount of PEO and PEG was adjusted to meet the tablet's total weight while maintaining the ratio between the two excipients constant. As the mixing time of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased. As the amount of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased since the increased mixing time and the amount of magnesium stearate induced hydrophobic properties of the matrix tablet more effectively. The ejection force of the tablet increased as a result of increase in the compression force, which means that the breaking of tablet/die-wall adhesion energy was also increased when the compression energy was increased. The results gavea valuable guide how to choose suitable amount of the lubricant with processing conditions for the development of hydrophilic matrix formulations.

Physical and Mechanical Properties of Board Made from Carbonized Rice Husk (왕겨숯을 이용하여 제조한 보드의 물성)

  • Hwang, Jung-Woo;Oh, Seung-Won
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.1
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    • pp.62-71
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    • 2017
  • This study was investigated on the properties of board made from carbonized rice husk differed in density of board, resin addition ratio and sawdust addition ratio. Water absorption is showed the lowest value to 80.09% when the resin addition ratio of 25%, as the density increased and sawdust addition ratio decreased, the water absorption was decreased. The measured thickness swelling satisfied with the quality standards of KS F 3104, so the feasibility of building interior has been confirmed in the dimensional stability. In case of resin addition ratio of 25%, the internal bond strength was satisfied quality standards of KS F 3104 to $0.244N/mm^2$. With increasing the density, resin and sawdust addition ratio, brinell hardness increased.

A Study on Characteristics of Hydraulic Conductivity in the Soil-Bentonite Mixed Soils with Compaction Energy and Swelling in the Landfill (폐기물매립장에서 다짐에너지와 팽윤도에 의한 토양-벤토나이트 혼합토의 투수계수 특성에 관한 연구)

  • 이종민;이재영
    • Journal of Soil and Groundwater Environment
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    • v.6 no.4
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    • pp.61-72
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    • 2001
  • A barrier liner system is placed at the bottom and side slope in landfill to protect a leaking of leachate that the hydraulic conductivity of this system should be less than It 107cm/sec. In this study, the soil-bentonite mixture for the bottom liner system was evaluated in two point of views : changing characteristics of the hydraulic conductivity according to the different mixing ratio of soil-bentonite with the effect of bentonite swelling and the difference method (A & D type) of compaction on the hydraulic conductivity. As the results, maximum dry density (${\gamma}$$_{dmax}$) of SC group mixture was higher than of CL group mixture. However, the result of optimum moisture contents(OMC) of both groups were the contrary. In case of ${\gamma}$$_{dmax}$ by different compaction method, D type was higher than A. But the OMC were the contrary. The difference of ${\gamma}$$_{dmax}$ according to the Compaction energy, “SC” group mixture W3S higher than the “CL” group. In case of OMC of “CL” group was higher than “SC” group. The effecting of swelling was a little bit different on the two factors. According to the result of compaction test, the use of site soil only could not meet the criteria on hydraulic conductivity, but could find a solution for the mixing ratio of bentonite mixture were satisfied to the standard of barriation. The increased in bentonite mixing ratio and degree of swelling, the values of hydraulic conductivity were decreased. Especially the “CL” group with “D” type compaction measured the lowest value with the same conditions. Also, the bentonite mixing ratio has more influenced on the hydraulic conductivity compare with swelling effect. The “SC” group mixture with “A” typo compaction got a big difference from others. The evaluation of economic for the construction cost on the two cases, the lower bentonite mixing ratio of soil-bentonite mixed soil is more economically because of bentonite cost.

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Preparation and Characterization of Biodegradable Hydrogels for Tissue Expander Application (조직 확장기용 생분해성 하이드로젤의 제조 및 특성분석)

  • Yuk, Kun-Young;Kim, Ye-Tae;Im, Su-Jin;Garner, John;Fu, Yourong;Park, Ki-Nam;Park, Jeong-Sook;Huh, Kang-Moo
    • Polymer(Korea)
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    • v.34 no.3
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    • pp.253-260
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    • 2010
  • In this study, we prepared and evaluated a series of biocompatible and biodegradable block copolymer hydrogels with a delayed swelling property for tissue expander application. The hydrogels were synthesized via a radical crosslinking reaction of poly(ethylene glycol) (PEG) diacrylate and poly(D,L-lactide-co-glycolide)-poly(ethylene glycol)-poly(D,L-lactide-co-glycolide)(PLGA-PEG-PLGA) triblock copolymer diacrylate as a swelling/degradation controller (SDC). For the synthesis of various SDCs that can lead to different degradation and swelling properties, various PLGA-PEG-PLGA triblock copolymers with different LA/GA ratios and different PLGA block lengths were synthesized and modified to have terminal acrylate groups. The resultant hydrogels were flexible and elastic even in the dry state. The in vitro degradation tests showed that the delayed swelling properties of the hydrogels could be modulated by varying the chemical composition of the biodegradable crosslinker (SDC) and the block ratio of SDC/PEG. The histopathologic observation after implantation of hydrogels in mice was performed and evaluated by macrography and microscopy. Any significant inflammation or necrosis was not observed in the implanted tissues. Due to their biocompatibility, elasticity, sufficient swelling pressure, delayed swelling and controllable degradability, the hydrogels could be useful for tissue expansion and other biomedical applications.

Oral tissue response to soft tissue expanders prior to bone augmentation: in vitro analysis and histological study in dogs

  • Yoo, Jung Min;Amara, Heithem Ben;Kim, Min Kyoung;Song, Ju Dong;Koo, Ki-Tae
    • Journal of Periodontal and Implant Science
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    • v.48 no.3
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    • pp.152-163
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    • 2018
  • Purpose: To determine whether the swelling and mechanical properties of osmotic self-inflating expanders allow or not the induction of intraoral soft tissue expansion in dogs. Methods: Three different volumes (0.15, 0.25, and 0.42 mL; referred to respectively as the S, M, and L groups) of soft tissue expanders (STEs) consisting of a hydrogel core coated with a silicone-perforated membrane were investigated in vitro to assess their swelling behavior (volume swelling ratio) and mechanical properties (tensile strength, tensile strain). For in vivo investigations, the STEs were subperiosteally inserted for 4 weeks in dogs (n=5). Soft tissue expansion was clinically monitored. Histological analyses included the examination of alveolar bone underneath the expanders and thickness measurements of the surrounding fibrous capsule. Results: The volume swelling ratio of all STEs did not exceed 5.2. In tensile mode, the highest mean strain was registered for the L group ($98.03{\pm}0.3g/cm$), whereas the lowest mean value was obtained in the S group ($81.3{\pm}0.1g/cm$), which was a statistically significant difference (P<0.05). In addition, the S and L groups were significantly different in terms of tensile strength ($1.5{\pm}0.1g/cm$ for the S group and $2.2{\pm}0.1g/cm$ for the L group, P<0.05). Clinical monitoring showed successful dilatation of the soft tissues without signs of inflammation up to 28 days. The STEs remained volumetrically stable, with a mean diameter in vivo of 6.98 mm, close to the in vitro post-expansion findings (6.69 mm). Significant histological effects included highly vascularized collagen-rich fibrous encapsulation of the STEs, with a mean thickness of $0.67{\pm}0.12mm$. The bone reaction consisted of resorption underneath the STEs, while apposition was observed at their edges. Conclusions: The swelling and mechanical properties of the STEs enabled clinically successful soft tissue expansion. A tissue reaction consisting of fibrous capsule formation and bone loss were the main histological events.

The Effects of Sophorae radix Extracts on CGRP Immunoreactive Neurons of Spinal Cord and Ganglia in Experimental Arthritic Rat Model (실험적 관절염 흰쥐 모델에서 고삼추출액이 척수와 척수신경절의 CGRP 면역반응 신경원에 미치는 영향)

  • Shin Hyun Jong;Lee Kwang Gyu;Ryuk Sang Won;Lee Sang Ryong;Ko Byung Moon;Lee Chang Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.1
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    • pp.117-123
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    • 2002
  • To investigate the antiinflammatory and analgesic effects of Sophorae radix extracts administered to the arthritic rat model, immunohistochemical stains for CGRP in the L4, L5 and L6 spinal cord and ganglia were done, and paw swelling thickness were measured. Complete Freund,s Adjuvant(CFA) were injected to subcutaneous tissue of left foot paw of rats to induce arthritis. Sophorae radix extracts was administered immediately after CFA injection for 10 days. The spinal cord and ganglia were frozen sectioned(30㎛). These sections were stained by CGRP immunohistochemical staining method, and observed with light microscope. The results were as follows : 1. The change of paw swelling thickness of experimental group decreased from 4 day to 10day after CFA injection compared to control group. 2. The change of differential leukocytes counts of experimental group increased the ratio of lymphocytes. and decreased the ratio of neutrophils compared to control group. 3. The change of CGRP immunoreactive nerve fiber of dorsal horn of experimental group was dense stained compared to control group. 4. The number of CGRP immunoreactive neurons of L4 and L5 spinal cord of experimental group was less than in those control group. These results suggested that Sophorae radix extracts reduces the number of CGRP immunoreactive neurons and nerve fibers of spinal cord and ganglia, and decrease paw swelling thickness in arthritic rat model, which may be closely related to analgesic and antiinflammatory effects of Sophorae radix.

Surface Treatment of Silica Nanoparticles and the Characteristics of their Composites with Thermoplastic Polyurethane Elastomer (실리카 나노입자의 표면처리와 이를 포함한 열가소성 폴리우레탄 복합소재의 특성)

  • Yoo, Sun Hwa;Song, Hyun Jae;Kim, Chang Keun
    • Polymer(Korea)
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    • v.36 no.6
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    • pp.721-726
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    • 2012
  • Thermoplastic polyurethane (TPU) elastomer is used as an encapsulant in undersea sonar devices. A new material for sonar encapsulant exhibiting better mechanical strength than TPU along with a lower swelling ratio for seawater and oil is required to prolong its application. TPU grafted silica nanoparticles (TPU-g-silica) were prepared and then they were melt mixed with TPU to fabricate desirable composites for underwater applications. The composite containing silica nanoparticles exhibited better tensile strength and lower swelling ratios in the seawater and oil than TPU regardless of the surface treatment of the silica particles. At fixed silica content in the composite, the TPU/TPU-g-silica composite exhibited better tensile strength and lower swelling ratio than the TPU composite with the pristine silica particles. Furthermore, the TPU/TPU-g-silica composite exhibited enhanced tensile strength as compared to TPU after being impregnated with oil.

Preparation and in vitro Evaluation of a Buoyant Hydrogel Matrix with Hydroxypropylcellulose and Carbopol (히드록시프로필셀룰로오스와 카르보폴을 이용한 부유성 히드로겔 매트릭스의 제조 및 in Vitro 평가)

  • Kim, Sang-Hun;Lee, Min-Suk;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.26 no.2
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    • pp.137-144
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    • 1996
  • The study was carried out for the preparation and evaluation of a buoyant hydrogel matrix (BHM), which is buoyant in a neutral or in pH 2.0 buffer solution, by the aspects of buoyancy, swelling, and drug release. Physical mixtures of HPC and CP in various molar ratio were employed as a mucoadhesive polymer which swells and controls the rate of drug release. Anhydrous citric acid and sodium bicarbonate in the molar ratio of 1:3 were employed as effervescing agents which provide a buoyancy for the mucoadhesive polymeric matrix. The buoyancy in vitro was expressed as both floating time$(T_{fl})$ and surfing time$(T_{sf})$, which are the time required for floating from the bottom to the surface of the medium and the time to keep the floated state at the surface of medium during release studies, respectively. A close relationship was observed between the buoyancy and the amount of effervescing agent added. $T_{fl}$ of the buoyant hydrogel matrices were decreased to about 10 seconds linearly with increasing the amount of effervescing agent in the range of 5 to 15%. $T_{sf}$ of the buoyant hydrogel matrices were varied from 1 to 3 hr depending on the amount of effervescing agent. The swelling was observed by changes in diameter of the buoyant hydrogel matrices in distilled water or acidic buffer solution, resulted in dependences on pH and the amount of effervescing agents. The release of hydrochlorothiazide from the buoyant hydrogel matrices were followed by apparent zero-order kinetics, while the buoyant hydrogel matrices were floated at the surface and maintaining their swollen shapes.

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