• Title/Summary/Keyword: surface pre-treatment

Search Result 400, Processing Time 0.022 seconds

Optimization of Thermal-alkaline Pre-treatment for Anaerobic Digestion of Flotation Scum in Food Waste Leachate Using Box-Behnken Design and Response Surface Methodology (Box-Behnken 및 반응표면 분석법을 이용한 음식물류 폐수 부상 스컴의 혐기성 소화를 위한 열-알칼리 전처리 최적화)

  • Lee, Dong-Young;Choi, Jae-Min;Kim, Jung-Kwang;Han, Sun-Kee;Lee, Chae-Young
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.29 no.2
    • /
    • pp.183-192
    • /
    • 2015
  • Response surface methodology (RSM) based on a Box-Behnken Design (BBD) was applied to optimize the thermal-alkaline pre-treatment operating conditions for anaerobic digestion of flotation scum in food waste leachate. Three independent variables such as thermal temperature, NaOH concentration and reaction time were evaluated. The maximum methane production of 369.2 mL $CH_4/g$ VS was estimated under the optimum conditions at $62.0^{\circ}C$, 10.1% NaOH and 35.4 min reaction time. A confirmation test of the predicted optimum conditions verified the validity of the BBD with RSM. The analysis of variance indicated that methane production was more sensitive to both NaOH concentration and thermal temperature than reaction time. Thermal-alkaline pretreatment enhanced the improvement of 40% in methane production compared to the control experiment due to the effective hydrolysis and/or solubilization of organic matters. The fractions with molecular weight cut-off of scum in food waste leachate were conducted before and after pre-treatment to estimate the behaviors of organic matters. The experiment results found that thermal-alkaline pre-treatment could reduce the organic matters more than 10kD with increase the organic matters less than 1kD.

Experimental Study of Condensation Heat Transfer in Pre-heating Exchanger to the Type of Hydrophilic Surface Treatment (친수 표면처리 종류에 따른 공기 예열 열교환기의 응축 열전달 실험적 연구)

  • Seok, Sungchul;Chung, Tae-Yong;Chin, Donghoon;Hwang, Seungsik;Choi, Gyuhong;Park, Jaewon
    • 한국연소학회:학술대회논문집
    • /
    • 2012.11a
    • /
    • pp.237-238
    • /
    • 2012
  • Recently, an energy-saving due to the energy utilisation efficiency enhancement is important. In order to improve the heat efficiency of the general residential boiler, We performed an experiment of condensation heat transfer to air pre-heat exchanger adhered to the condensing boiler. In this research, We analyze the heat transfer performance through the hydrophilic surface treatment(plasma, etching). The results of the research, On plasma and etching treated surface, Overall heat transfer coefficient is displayed the tendency to increase.

  • PDF

Potassium loading effects for activated carbon fiber pre-treated with phosphoric acid (인산을 전처리한 활성탄소섬유에 칼륨 처리효과)

  • Oh, Won-Chun;Bae, Jang-Soon
    • Analytical Science and Technology
    • /
    • v.18 no.4
    • /
    • pp.355-361
    • /
    • 2005
  • The objective of this paper is to compare the surface features of two kinds of activated caron fiber (ACF) treated with potassium and the variation of their properties by phosphoric acid pre-treatment. X-ray diffraction (XRD) patterns indicate that activated carbon fiber containing potassium species show better performance for metal and metal salts by pre-treatment with phosphoric acid. In order to present the causes of the differences in surface properties and specific surface area after the samples were treated with phosphoric acid, pore structure and surface morphology were investigated by adsorption analysis and SEM. For the chemical composition microanalysis for potassium leading of the activated carbon fibers pre-treated with phosphoric acid, samples were analyzed by EDX. Finally, the type and quality of oxygen groups were determined from the method proposed by Boehm.

Mechanisms of Platelet Adhesion on Elastic Polymer Surfaces: Protein Adsorption and Residence Effects

  • Insup Noh;Lee, Jin-Hui
    • Macromolecular Research
    • /
    • v.9 no.4
    • /
    • pp.197-205
    • /
    • 2001
  • Platelet adhesion onto elastic polymeric biomaterials was tested in vitro by perfusing human whole blood at a shear rate of 100 sec$\^$-1/ for possible verification of mechanisms of initial platelet adhesion perfusion of blood on the polymeric substrates was performed after treatments either with or without pre-adsorption of 1% blood plasma, and either with or without residence of the protein-preadsorbed substrate in phosphate buffered solution. The surfaces employed were elastic polymers such as poly(ether urethane urea), poly(ether urethane), silicone urethane copolymer, silicone rubber and poly(ether urethane) with the anti-calcifying agent hydroxyethane bisphosphate. Each polymer surface treated was exposed in vitro to the dynamic, heparinized whole blood perfused for upto 6 min and the surface area of platelets initially adhered was measured by employing in situ epifluorescence video microscopy. The blood perfusion was performed on the surfaces treated at the following three different conditions: directly on the bare surfaces, after protein pre-adsorption and after residence in buffer for 3 days of the surfaces protein pre-adsorbed for 2 h. The effects of blood plasma pre-adsorption on the initial platelet adhesion was surface-dependent. The amount of the adsorbed fibrinogen and the surface coverage area of the adhered platelets were dependent on the surface conditions whether substrates were bare surfaces or protein pre-adsorbed ones. To test an effect of possible morphological (re)orientations of the adsorbed proteins on the initial platelet adhesion, the polymeric substrate pre-adsorbed with 1% blood plasma was immersed in phosphate buffered solution for 3 days and then exposed to physiological blood perfusion. The surface area of the platelets adhered on these surfaces was significantly different from that of the surfaces treated with protein pre-adsorption only. These results indicated that platelet adhesion was dependent on the surface property itself and pre-treatment conditions such as blood perfusion without any pre-adsorption of proteins, and blood perfusion either after protein pre-adsorption or after subsequent substrate residence in buffer of the substrate pre-adsorbed with proteins. Understanding of these results may guide for better designs of blood-contacting materials based on protein behaviors.

  • PDF

The Mordant Effects Used by Natural Tannin Dyed with Lac powder: Tara and Myrobalan (락(Lac) 염색시 천연탄닌의 매염효과: 타라와 미로발란)

  • Bai, Sangkyoung
    • Journal of Fashion Business
    • /
    • v.18 no.4
    • /
    • pp.114-124
    • /
    • 2014
  • This research was carried out to find the mordant effects by Tara and Myrobalan as natural tannins on the cow leather dyed with Lac powder. The cow leathers were treated with Tara, Myrobalan, Al, Cu, and Fe mordants by changing treatment orders. It was examined for K/S value, surface color changes, and color difference. The K/S value generally has higher Myrobalan than Tara, and pre-mordant than post-mordanted condition. Cu is the strongest among the three mordants. As a results of the treatment order, the K/S value is higer in pre-tannin-mordant agent than in pre-mordant agent-tannin. In the post mordant, K/S value is higher in mordant agent-tannin than in tannin-mordant agent. The color difference and color factors such as H, V and C were various according to the mordant agents, treatment orders and mordant methods; and surface colors of dyed cow leathers were R and RP. It was difficult to find some significant means of mordant orders.

Influence of Plasma Treatment & UV Absorbent on Lightfastness Improvement of Brazilin (플라즈마 전처리와 자외선 흡수제에 의한 소목의 내일광성 향상에 관한 연구)

  • 신정숙;손원교
    • The Research Journal of the Costume Culture
    • /
    • v.11 no.1
    • /
    • pp.66-74
    • /
    • 2003
  • This study is to improve the worst lightfastness of a natural dye. To modify the fiber surface, low temperature oxygen plasma was carried out on silk fabric. The result is followed below after the examination of surface shape, dyeability, color change, UV absorbent influence and lightfastness. 1. When electric discharge outputs are 60W, 80W and 100w, and processing times are 10minutes, 20minutes and 40minutes, the etching effect of surface increased as electric discharge outputs and processing times increased. 2. When examined UV absorbent for 5hours, 10hours, 20hours, 40hours and 80hours, the value changes of E are 1.47, 2.51, 2.91, 3.71, 4.51 and 5.31 in case of Al pre-mordanting/ prasma 80W, 20min./ UVabsorbent 5% (100:1), 2.31, 2.47, 3.84, 3.90, 3.61 and 4.42 in case of Al pre-mordanting/prasma 80W, 20min.1 UV absorbent 5% (o.w.f.). The lightfastness decreased when UV absorbent increased. 3. Dyeability of the samples pre-treated with five different methods was in the following order: plasma processing for 20minutes at 60W/Al pre-mordanting > Al pre-mordanting > plasma processing for 20minutes at 60W > Al after-mordanting. non mordanting Plasma treatment had superior effect on dyeability. 4. When UV absorbent was applied in fabric, the sample under higher electric discharge out puts showed more effective in improving lightfastness.

  • PDF

Effects of Pre-treatments on the Oil Palm EFB Fibers (오일팜 EFB 섬유의 전처리 영향 평가)

  • Kim, Dong-Seop;Sung, Yong Joo;Kim, Chul-Hwan;Kim, Se-Bin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.44 no.6
    • /
    • pp.36-42
    • /
    • 2012
  • The empty fruit bunch fibers(EFB) of oil palm were examined for optimal utilization of the EFB fibers. The EFB fibers were obtained by shredding EFB, followe by removal of fines. The surface properties of the fibers were modified with various pre-treatments, such as hot water extraction, the soaking treatments with NaOH, $ClO_2$ and n-hexane. The changes in the fiber surface were examined with FT-IR method, which showed the changes in chemical compositions such as pectin, lignin, and etc. according to the pre-treatment methods. And the z-directional tensile testing of the fiber mold made of the treated EFB fibers showed the changes in the bonding strength by the pre-treatments. The fiber mold made of EFB fibers treated with $ClO_2$ showed the greater increase in the tensile energy absorption although the NaOH treatment resulted in the severer impact on the EFB fibers.

A study on pre-bonding of Si wafer direct bonding at HF pre-treatment (HF 전처리시 Si기판 직접접합의 초기접합에 관한 연구)

  • Chung, Gwiy-Sang;Kang, Kyung-Doo
    • Journal of Sensor Science and Technology
    • /
    • v.9 no.2
    • /
    • pp.134-140
    • /
    • 2000
  • Si wafer direct bonding(SDB) technology is very attractive for both Si-on-insulator(SOI) electronic devices and MEMS applications. This paper presents on pre-bonding according to HF pre-treatment conditions in Si wafer direct bonding. The characteristics of bonded sample were measured under different bonding conditions of HF concentration and applied pressure. The bonding strength was evaluated by tensile strength method. A bond characteristic on the interface was analyzed by using FT-IR, and surface roughness according to HF concentration was analyzed by AFM. Si-F bonds on Si surface after HF pre-treatment are replaced by Si-OH during a DI water rinse. Consequently, hydrophobic wafer was bonded by hydrogen bonding of Si-OH$\cdots$(HOH$\cdots$HOH$\cdots$HOH)$\cdots$OH-Si. The pre-bonding strength depends on the HF pre-treatment condition before pre-bonding. (Min : $2.4kgf/cm^2{\sim}$Max : $14.9kgf/cm^2$)

  • PDF

The Study on the Effect of Plasma Pre-treatment on the Dyeing Properties and the Handle in the Environment Friendly Enzyme Finishing (친환경 효소가공에서 플라즈마 전처리가 염색성과 태에 미치는 영향)

  • Kim, Ji-Hyun
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.10 no.3
    • /
    • pp.173-180
    • /
    • 2008
  • Cotton, wool, cotton/wool blended (80:20) and tencel fabrics were treated with low temperature oxygen plasma, enzymes (cellulase or protease), or oxygen plasma-enzyme and they were examined for dyeing and handling properties for environment friendly finishing. The appropriate conditions for cellulase treatment were enzyme concentration of 3g/l, pH of 5, and $60^{\circ}C$ for one hour, and for protease treatment were enzyme concentration of 4g/l, pH of 8, and $60^{\circ}C$ for one hour. The equilibrium uptake of a direct dye on cotton changed with plasma treatment and plasma-cellulase treatment, and the rate of dyeing slightly decreased. When wool was dyed with acid dye, the equilibrium dye uptake did not change with plasma, protease treatment nor plasma-protease treatment, however, the rate of dyeing had increased with plasma-protease treatment. From these results, it is assumed that plasma attacks the surface of the fiber, and enzyme mainly affects the inner part of the fiber. Plasma treatment did not affect mechanical properties related to the handling of fabrics. The handling test showed increased extension at maxmum load(EM), tensile energy(WT) with decreased tensile resilience (RT), and the fabrics became softer but resilience decreased slightly with enzyme treatment. The bending recidity(B), hysteresis of bending moment(2HB), and hysteresis of shear force at five degrees(2HG5) decreased, however, shear stiffness(G) increased. I knew the plasma pre-treatment made fabrics softer with lower koshi(stiffness). The handling of plasma pre-treated fabrics was better than that of enzyme-treated fabrics. When we pre-treated fabrics, the handling test showed decreased coefficient of friction(MIU), geometrical roughness(SMD), while the surface of fabrics became smoother and numeri increased. Even though compression resilience(RC) increased, fukurami(bulky property) and compressive elasticity, decreased due to the linearity of compression-thickness curve(LC) and compression energy(WC).

  • PDF