• Title/Summary/Keyword: Reduced properties

검색결과 4,367건 처리시간 0.03초

Effect of chemically reduced graphene oxide on epoxy nanocomposites for flexural behaviors

  • Lee, Seul-Yi;Chong, Mi-Hwa;Park, Mira;Kim, Hak-Yong;Park, Soo-Jin
    • Carbon letters
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    • 제15권1호
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    • pp.67-70
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    • 2014
  • In this work, nanocomposites of epoxy resin and chemically reduced graphene oxide (RGO) were prepared by thermal curing process. X-ray diffractions confirmed the microstructural properties of RGO. Differential scanning calorimetry was used to evaluate the curing behaviors of RGO/epoxy nanocomposites with different RGO loading amounts. We investigated the effect of RGO loading amounts on the mechanical properties of the epoxy nanocomposites. It was found that the presence of RGO improved both flexural strength and modulus of the epoxy nanocomposites till the RGO loading reached 0.4 wt%, and then decreased. The optimum loading achieved about 24.5 and 25.7% improvements, respectively, compared to the neat-epoxy composites. The observed mechanical reinforcement might be an enhancement of mechanical interlocking between the epoxy matrix and RGO due to the unique planar structures.

공동주택 월풀욕조의 소음진동 특성 및 저감 방안 (The properties of noise and vibration in Whirlpool bath and plan for its reduction)

  • 배상환;이병권
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2005년도 동계학술발표대회 논문집
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    • pp.506-510
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    • 2005
  • This study shows work on the properties of noise and vibration in Whirlpool bath and plan for its reduction. Totally through 3 steps. we found out the properties of noise and vibration. various anti-vibration design for an effeciency test is conducted. By Anti-vibration for the pump causing vibration, about 4dB(A) was reduced. Moreover. by anti-vibration construction fixing the bathtub frame. about 3db(A) could be reduced. In the case of anti-vibration construction about the wall around the bathtub. and spreading damping paint on the bathtub. the noise was reduced.

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Improved Luminescence Properties of Polycrystalline ZnO Annealed in Reduction Atmosphere

  • Chang, Sung-Sik
    • 한국세라믹학회지
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    • 제48권3호
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    • pp.251-256
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    • 2011
  • The luminescence properties of polycrystalline ZnO annealed in reducing ambience ($H_2/N_2$) have been studied. An effective quenching of green luminescence with enhanced UV emission from polycrystalline ZnO is observed for the reduced ZnO. The variations of the UV and green luminescence band upon reduction treatment are investigated as a function of temperature in the range between 20 and 300 K. Upon annealing treatment in reducing ambience, the optical quality of polycrystalline ZnO is improved. The UV to green intensity ratio of sintered ZnO approaches close to zero (~0.05). However, this ratio reaches more than 13 at room temperature for polycrystalline ZnO annealed at $800^{\circ}C$ in reducing ambience. Furthermore, the full width at half maximum (FWHM) of the UV band of polycrystalline ZnO is reduced compared to unannealed polycrystalline ZnO. Electron paramagnetic resonance (EPR) measurements clearly show that there is no direct correlation between the green luminescence and oxygen vacancy concentration for reduced polycrystalline ZnO.

Properties of Cholesterol-reduced Butter and Effect of Gamma Linolenic Acid Added Butter on Blood Cholesterol

  • Jung, Tae-Hee;Kim, Jae-Joon;Yu, Sang-Hoon;Ahn, Joungjwa;Kwak, Hae-Soo
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권11호
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    • pp.1646-1654
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    • 2005
  • The present study was carried out to develop cholesterol-reduced and gamma linolenic acid (GLA)-added butter and to examine the changes in chemical and sensory properties, and cholesterol lowering effect of GLA addition. The cholesterol removal rate reached 93.2% by $\beta$-cyclodextrin in butter before GLA addition. The thiobarbituric acid value of cholesterol-reduced and GLA-added butter increased slowly up to 4 week and plauteaued thereafter. TBA value was significantly increased with 2% GLA addition, compared with no GLA addition. The production of short-chain free fatty acids (FFA) increased with storage in all treatments. From 4 weeks storage, the amount of short-chain FFA in 2% GLA-added group was significantly higher than those in other groups. Among sensory characteristics, color, greasiness and overall acceptability were mostly affected by GLA addition, however, the rancidity value of 2% GLA addition was significantly different from those of control and GLA-unadded and cholesterol-reduced butter at 0, 6 and 8 week storage. Among groups, no difference was found in texture in all storage periods. The smallest increase of total blood cholesterol in rats was found in the group fed 2% GLA-added and cholesterol-reduced butter for 8 week, compared with that in controls. The present results showed the possibility of cholesterol-reduced and GLA-added butter development without much difference in chemical, rheological and sensory properties, and indicated a slow increase effect on blood total cholesterol in rats.

Evaluation of salt level and rigor status on the physicochemical and textural properties of low-fat pork sausages added with sea tangle extract using rapidly chilled pre-rigor pork ham

  • Geon Ho Kim;Koo Bok Chin
    • Animal Bioscience
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    • 제36권9호
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    • pp.1445-1452
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    • 2023
  • Objective: This study was performed to evaluate the quality characteristics of pork sausage (PS) with sea tangle extract (STE) and rapid chilled pre-rigor muscle (RCPM) for the development of reduced-salt low-fat sausage. Methods: Pre- and post-rigor pork ham muscles were prepared to process PSs. Positive control (reference, REF) using post-rigor muscle were manufactured at a regular-salt level of 1.5%. Fresh and rapid-chilled pre-rigor muscle (FPM and RCPM) were used to manufacture reduced-salt sausages with 0.8% salt. Reduced-salt PSs were prepared with four treatments: FT1 (FPM alone), FT2 (FPM with 5% STE), RT1 (RCPM alone), and RT2 (RCPM with 5% STE). The physicochemical and textural properties of the sausages with reduced-salt levels and RCPM combination were measured to determine if the characteristics of RCPM were similar to those with FPM. Results: The pH values of PS with FPM and RCPM were higher than those of REF with post-rigor muscle. Color values (L*, a*, b*) were not affected by different rigor-states and salt addition level. Textural properties of reduced-salt PSs were similar to those of REF due to the improved functionalities of pre-rigor muscle. RT2 had lower expressible moisture (%) than other treatments with post-rigor muscle and RCPM except for RT1. Conclusion: The addition of STE and RCPM to reduced-salt PS increased the water-holding capacity, which was lower than those of PS with STE using RCPM but similar to those of regular-salt sausage.

데침과 열수의 침적과 Trehalose 처리가 오이 물김치의 저장중 품질에 미치는 영향 (The Properties of Blanching and Brining in Hot Solution and Trehalose Treatment on the Quality of Cucumber Kimchi during Fermentation)

  • 이혜정
    • 한국식품영양학회지
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    • 제14권4호
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    • pp.333-338
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    • 2001
  • In research. which Korean pickled cucumber was treated wish various methods, including blanching. brining in hot solution, and treating with trehalose. I examined the changes of properties of material. The Korean pickled cucumber were fermented 4∼5$^{\circ}C$ for 42 days in 1% salt solution. The physiochemical properties were pH, total acidity, total cell count, lactic acid bacteria and texture properties were also evaluated. The result showed that the effect of blanching and soaking cucumber in 100$^{\circ}C$ hot salt solution significantly reduced the softening rate of texture while a rather rapid fermentation was found for those preserved with salt. The effect of trehalose treatment inhenced fermentation but it was significantly reduced softening rate of texture. The texture evaluation of Korean pickled cucumber was found that heat treatment with blanching after soaked in hot solution and trehalose treatment had a positive effect for reduction of softening of cucumber tissue.

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Effect of sea tangle extract on the quality characteristics of reduced-salt, low-fat sausages using pre-rigor muscle during refrigerated storage

  • Geon Ho Kim;Koo Bok Chin
    • Animal Bioscience
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    • 제36권11호
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    • pp.1738-1746
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    • 2023
  • Objective: The aim of this study was to investigate quality characteristics of reduced-salt, low-fat pork sausage (PS) using pre-rigor muscle and sea tangle extract (STE) to reduce salt level of sausages during refrigerated storage. Methods: Pork ham was prepared with pre-rigor and post-rigor muscle from the local market. Sausages using post-rigor muscle were manufactured with the 1.5% of salt content, and samples with pre-rigor muscle were processed by different salt concentrations (0.8%). Accordingly, PSs were prepared in 4 treatments (REF, PS with 1.5% of salt using post-rigor muscle; CTL, PS with 0.8% of salt using pre-rigor muscle; TRT1, PS with 0.8% of salt and 5% of STE using pre-rigor muscle; TRT2, PS with 0.8% of salt and 10% of STE using pre-rigor muscle). For the evaluation of quality characteristics and shelf-life of reduced-salt PS, pH and color values, cooking loss (%), expressible moisture (%), textural properties, lipid oxidation (thiobarbituric reactive substances), protein denaturation (volatile basic nitrogen), and microbiological analysis (total plate counts and Enterobacteriaceae counts) were determined. Results: The pH and temperature of pre-rigor raw pork ham were higher than those of post-rigor pork ham. Hardness of TRT2 was higher than that of REF or CTL. TRT2 had higher gumminess and chewiness than CTL. TRT1 and TRT2 had lower volatile basic nitrogen than CTL. Total plate counts of TRT2 were lower than those of CTL. Expressible moisture values of TRT1 and TRT2 were similar to those of REF. The addition of STE into PS improved functional properties and shelf-life of PS. Conclusion: Reduced-salt PS containing pre-rigor muscle and STE had similar functional properties to those of regular-salt ones, while containing approximately 47% less salt compared to regular-salt level.

ON STRONG REGULARITY AND RELATED CONCEPTS

  • Cho, Yong-Uk
    • Journal of applied mathematics & informatics
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    • 제28권1_2호
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    • pp.509-513
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    • 2010
  • In this paper, we will investigate some properties of strongly reduced near-rings. The purpose of this paper is to find more characterizations of the strong regularity in near-rings, which are closely related with strongly reduced near-rings.

이산시스템의 positive real 특성을 유지하는 일반화된 특이 섭동 근사화 (Generalized singular perturbation approximation preserving positive real property of discrete system)

  • 오도창;김재권;방경호;박홍배
    • 전자공학회논문지S
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    • 제34S권9호
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    • pp.50-59
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    • 1997
  • This paper is on the generalized singular perturbation approximation (GSPA) preserving the discrete positive real property. We transform the discrete positive real(PR) system into a stochastically banlanced system and get the reduced order discrete system from the GSPA of the full order stochastically balanced system. eSPECIALLY, WHEN THE FREE PARAMETER OF THE gspa IS .+-.1, we show that the reduced order discrete system retains stability, minimality, and positive real and stochstically balancing properties. And we derived the .inf.-norm error bound with the reduced order discrete strictly positive real(SPR) system by the proposed method. Finally, we give an example to ascertain the properties of the proposed reduced order discrete system and to compare with the conventional methods.

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ON STRONG FORM OF REDUCEDNESS

  • Cho, Yong-Uk
    • 호남수학학술지
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    • 제30권1호
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    • pp.1-7
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    • 2008
  • A near-ring N is said to be strongly reduced if, for a ${\in}$ N, $a^2{\in}N_c$ implies $a{\in}N_c$, where $N_c$ denotes the constant part of N. We investigate some properties of strongly reduced near-rings and apply those to the study of left strongly regular near-rings. Finally we classify all reduced and strongly reduced near-rings of order ${\leq}$ 7 using the description given in J. R. Clay [1].