• Title/Summary/Keyword: blending effect

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Thermal Properties of Linear Shape Polylactic Acid/Star Shape Polylactic Acid Blends (선형 폴리락틱산/스타형 폴리락틱산 블렌드의 열적 특성 변화에 대한 연구)

  • 천상욱;김수현;김영하;강호종
    • Polymer(Korea)
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    • v.24 no.3
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    • pp.333-341
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    • 2000
  • Blends consisting of linear shape polylactic acid and star shape polylactic acid (L-PLLA/S-PLLA) have been prepared by melt and solution blending. The effect of blending method on the thermal properties and crystallization behavior of L-PLLA/S-PLLA blends has been investigated. The molecular weight decrease was revealed both in melt and solution blending. S-PLLA was found to be more stable than L-PLLA in the reduction of molecular weight during the course of blending due to its star shape structure. As a result, broad molecular weight distribution was obtained in solution blending. It was found that melting temperature and glass transition temperature decrease with increasing S-PLLA content. Blending method had large influence on the glass transition temperature of PLLA blends, while less effect on melting temperature. From DSC results, it can be noticed that solution blending is more effective blending method to obtain higher crystallinity than melt blending for S-PLLA and blend with higher S-PLLA content.

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Effect of Dry Ice Expanded Tobacco Blending Ratio on the Physical Properties of Cigarettes ($CO_2$를 이용하여 팽화된 각초배합율이 제조담배 물성에 미치는 영향)

  • Lee, Young-Tack;Jo, Si-Hyung;Kim, Sung-Han;Baek, Shin;Rhim, Kwang-Soo;Kim, Young-Ho;Shin, Chang-Ho
    • Journal of the Korean Society of Tobacco Science
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    • v.18 no.2
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    • pp.145-149
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    • 1996
  • The experiment was carried out to study the effect of dry ice expanded tobacco (DIET) blending ratio on the physical properties of cigarettes. Vnencapsulated pressure drop (UPD) of the cigarette decreased from 85 mmWG to 78 mWG when the DIET blending ratio increased from 0% to 60%, but it increased in the range of over 60% blending ratio. But the overall UPD/EPD ratio of these cigarettes showed a decreasing tendency. Cigarette ventilation rate increased from 55% to 66% with the increased blending ratio of expanded tobacco and loose ends also showed the same tendency. The higher the blending ratio of expanded tobacco, the faster became the static burning time from 7' 34" to 5' 02". However, the cigarette hardness was almost not affected by the blending ratio.ing ratio.

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Influence of blending method with different SR on unburned carbon and NOx emission and its application

  • Lee, Byoung-Hwa;Edding, Eric G.;Jeon, Chung-Hwan
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.39-41
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    • 2012
  • The influence of coal blending methods such as out-furnace (external or pre-mixed) blending and in-furnace (initially non-mixed) blending with different excess oxygen (highest, medium, and lowest stoichiometric conditions) on unburned carbon and NOx emissions of blend combustion in an entrained flow reactor (EFR) has been analyzed, using experimental and numerical approaches for binary coals used by Korean power plants. The results confirm that under the medium condition, contrasting processes such as reactive and un-reactive effects occur with SBRs in the out-furnace blending method. The in-furnace blending method results in an improvement in the efficiency of unburned carbon fractions and a further reduction in the NOx emission. Under the highest condition, the unburned carbon fraction in both the out-furnace and the in-furnace blending methods corresponds with the tendency under the medium condition with contrasting processes of lower magnitude, whereas the NOx emission in the highest condition increases slightly. Under the lowest conditions, the unburned carbon fraction in the out-furnace blending method gradually decreases as SBR decreases, without a competition effect. The reduction of NOx emission under the lowest conditions is more effective than those under other conditions for the two blending methods because of a homogeneous and heterogeneous NOx reduction mechanism.

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An Effect of Blending Materials on the Strength Characteristics of High Strength Cement Composite (고강도 시멘트 복합체의 강도특성에 미치는 혼합재료의 영향)

  • 최일규;김정환;한기성
    • Journal of the Korean Ceramic Society
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    • v.31 no.3
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    • pp.330-336
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    • 1994
  • High strength cement composites (W/C=0.1) were prepared by using various blending materials such as SiC whisker and white carbon (hydrated silica: SiO2·nH2O). The effect of various blending materials on the microstructure and strength of the hardened cement paste were investigated in the view of fracture mechanics. The plain specimen showed 101 MPa of flexural strength, 81 GPa of Young's modulus and 1.32 MPam1/2 of fracture toughness. When the blending materials were added to the composites, their values were enhanced to about 110∼138 MPa, 95∼146 GPa and 1.32∼1.87MPam1/2 respectively. The improvement of the mechanical strength for the hardened cement paste may be due to the removal of macropores, the reduction of total porosity, pozzolanic reaction and the increase of various fracture toughening effect.

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Blending Effect on the Mechanical and Hand Properties of Wool/Acrylic Blend Knits

  • Park Myung-Ja
    • The International Journal of Costume Culture
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    • v.8 no.1
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    • pp.23-31
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    • 2005
  • Mechanical properties and hand evaluation of wool/acrylic(W/A) blend knits were conducted before and after repeated washing to get the optimum W/A blending ratio, which could help achieve the optimum mechanical and hand properties of the knits. The five test fabrics using the yarns with different W/A blending ratios($\%$), 100/0, 70/30, 50/50, 30/70, 0/100, were knitted. The fabrics were washed by a rotating drum type washing machine. Then, objective mechanical and hand properties were evaluated by KES-FB, Kawabata evalution system for fabric. The results are as follows: there was no change in the hand value of the knitted fabric with the W/A-blended yarn caused by the change in the blending ratio before washing. After washing, however, the increase of acrylic's blending rate caused the bending property to decrease proportionally, while the friction coefficient of the surface property increased. Furthermore, the study showed that W/A 50/50 possesses the most superior tensile property and shearing property, which could attain the optimum blending ratio. Similar results in hand value were derived in all the samples. After washing, however, the increase in acrylic's blending rate caused a proportional decrease in KOSHI and an increase in FUKURAMI. In addition, W/A 50/50 gained the biggest NUMERI value, again corresponding to the optimum blending ratio. Similar results in total hand value were derived in all the samples before washing. After washing, though, all the total hand values decreased, and, as the wool fabric's blending rate increased, the total hand values proportionally decreased further.

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Antibacterial Effects of Tea Tree Oil and Mastic Oil to Streptococcus mutans

  • Song-Yi Yang;So-Hyun Lee;On-Bi Park;Hee-Rang An;Yeong-Hyeon Yu;Eun-Bi Hong;Kyung-Hee Kang;Hwa-Soo Koong
    • Journal of dental hygiene science
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    • v.23 no.1
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    • pp.51-59
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    • 2023
  • Background: Tea tree oil has antiviral, antimicrobial and antifungal effects and Mastic oil has antifungal and anticancer effects. For synergistic effects of oils, blending oil containing a mixture of two to three oils is recommended. This study aimed to determine the antibacterial effects of Tea tree oil, Mastic oil, and Blending oil containing the two oils in a mixture, to verify and suggest the potential use of these oils as a substance to prevent dental caries. Methods: Tea tree oil, Mastic oil, and Blending oil with a 1:1 blend of the two oils were diluted in liquid medium to 0% (negative control), 0.5%, 1.0%, and 2.0%. Streptococcus mutans was applied to each experimental group of the three diluted oils and after 8 h culture, the optical density (OD) was measured and the growth inhibition rate for S. mutans was estimated. Results: Tea tree oil had significantly low OD values across all concentrations (p<0.05) without significant variation among different concentrations (p>0.05). Mastic oil did not significantly vary in OD compared to the negative control across all concentrations (p>0.05) without significant variation among different concentrations (p>0.05). Blending oil, compared to the negative control, did not significantly vary in OD at 0.5% (p>0.05) but significant variation was found as the concentration increased (p<0.05). Additionally, for Tea tree oil and Mastic oil, the growth inhibition rate showed no significant variation according to concentration (p>0.05), whereas for Blending oil, the growth inhibition rate for S. mutans showed a significant difference at 1.0% (p<0.05) and at higher concentrations. Conclusion: Blending oil containing a Tea tree oil and Mastic oil demonstrated a significant growth inhibition effect on S. mutans from the concentration of 1.0%, which suggested its potential use as an effective antibacterial agent for dental caries.

Effect of vacuum blending on antioxidant activities of apple juice and blueberry juice

  • Lee, Sung-Gyu;Lee, Min-Seo;Seo, Soo-Min;Park, Seong-Yun
    • Journal of Plant Biotechnology
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    • v.48 no.4
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    • pp.271-277
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    • 2021
  • The present study aimed to assess and compare the quality characteristics and antioxidant activities of apple juice and blueberry juice at hourly intervals over a period of time based on the presence or absence of vacuum blending (0 and 800 hPa) using a household blender. Measurement of the dissolved oxygen content revealed that the removal rates of dissolved oxygen were approximately 83% and 86% in the apple and blueberry juice samples, respectively, after vacuum blending. Moreover, compared with general blending, there was little change in the antioxidant property and degree of browning over time with vacuum blending. Furthermore, hourly assessments revealed that the decrease in the polyphenol and flavonoid contents in the apple and blueberry juice samples was significantly lesser with vacuum blending for 3, 6, and 12 h than with general blending. Assessment of the change in ferric reducing antioxidant power (FRAP) activity over time revealed that the rate of decrease in FRAP activity over time was lower with vacuum blending than with general blending for both juice samples. ABTS and DPPH radical scavenging assays performed to determine the change in free radical scavenging activity revealed inhibitory activity at 0, 3, 6, and 12 h and confirmed that vacuum blending resulted in long-lasting antioxidant activities in both apple and blueberry juice samples. Taken together, the present results confirmed that vacuum blending is associated with superior quality maintenance and antioxidant properties in comparison with general blending.

Synergistic Effect of Tocopherol, Citric Acid and Sodium Polyphosphate on the Thermal Oxidation of Blending Oil (혼합유(混合油)의 열산화(熱酸化)에 대(對)한 Tocopherol, 구연산 및 인산염(燐酸鹽)의 상승효과)

  • Chang, Hun-Ki
    • Journal of the Korean Applied Science and Technology
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    • v.7 no.1
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    • pp.63-70
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    • 1990
  • Influence of mixing ratio of blending oil (rice bran oil : RBD palm olein = 1 : 1, 1 : 4 mixture: w/w) and natural tocopherol, citric acid, and sodium polyphosphate on enhancement of oxidation stability of blending oil under the condition of tap water infulx(1 ml/min/200g oil) were compared by AOM test after heating these system at l80$^{\circ}C$. In addition, the effects of tocopherol, and synergist on oxidition stability were also tested with potato chips fried with blending oil(1 : 4 mixture). The result obtained were as followes; 1. The test of RBD palm olein addition of 50% and 80% against rice bran oil on oxidation stability showed that the higher the palm olein contents in blending oil, the higher the oxidation stability. 2. The test of oxidation stability, adding l00ppm, 200ppm and 400ppm of natural tocopherol in two different types of blending oils, A(1 : 1 mixture) and B(1 : 4 mixture), disclosed that blending oil B was more positively effective, and this trend was superior at 200ppm level particularly, Furthermore, oxidation stability was enhanced remarkably upon addition of 100ppm of natural tocopherol, and 50ppm of citric acid together with 50ppm, 100ppm and 200ppm of sodium polyphosphate in general. Especially, 200ppm of sodium polyphosphate addition induced the most synergetic effect on oxidation stability showing as much as 3 times compare to control. 3. The results of oxidation stability obtained by peroxide value on potato chips fried with blending oil (1:4 mixture} added tocopherol, citric acid and sodium polyphosphate and preserved at $60^{\circ}C$ revealed that addition of tocopherol and 50ppm of citric acid together with 200ppm of sodium polyphosphate treatment was the most synergistic coinciding with AOM test results.

Freezing and Thawing Resistance of Hardened Cement Paste Containing Blending Materials (혼합재를 사용한 시멘트경화체의 동결융해 저항성)

  • 이양수;김정환;최상흘;한기성
    • Journal of the Korean Ceramic Society
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    • v.27 no.3
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    • pp.437-443
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    • 1990
  • The resistivity of cement paste and mortar for freezing and thawing was investigated for densifying the structure of cement paste and mortor, slag, diatomaceous earth and fly ash as blending materials and superplasticizer were used, and air entraining agent was added to absorb the volume expansion by freezing and thawing reaction. And then the specimens were subjected to freeze-thaw in water. When both of air entraining agent and superplasticizer as additives were mixed to specimens, their freeze-thaw resistance was enhanced by the air entraining effect and the water reduction effect. When 4% of slag were added to cement, freeze-thaw resistance was especially excellent. In addition, it was found that the specimens with blending materials were more influenced by curing periods than those without admixture. It is assumed that the curing periods contribute to exibit the potential hydraulicity and pozzolanic reactivity of blending materials and to densify their texture.

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The Effect of Essential Oil on Atopic Dermatitis Model of NC/Nga Mice (라벤더, 로즈마리, 레몬밤을 이용한 생쥐의 아토피피부염모델에 대한 효과)

  • Han, Sun Hee;Seo, Young Mi
    • Journal of Korean Biological Nursing Science
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    • v.16 no.3
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    • pp.219-225
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    • 2014
  • Purpose: This study was aimed to evaluate the effect of blending oils on atopic dermatitis (AD) model of NC/Nga mice. Methods: Adult NC/Nga mice were assigned to 1 of 3 groups: control group (C, n=8), experimental group [AD-induced group, blending oil-treated group (E=8, 8)]. Mice in the E group were given a treatment of blending oils such as Lavender, Rosemary and Lemon Balm (LRL) for 2 sessions (every day) for 6 days. Results: The AD-induced mice with LRL blending oils treatment showed a significant decrease in epidermal thickness, number of mast cells and degranulation, expression of TNF-${\alpha}$ and scoring of sensual assessment. Conclusion: LRL blending oils may be a putative resource for the cure of or treatment of AD by the diminution of AD-pathological factors such as the epidermal thickness, the number of mast cells and degranulation as well as the expression of TNF-${\alpha}$.