• 펄프종이기술
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• 제47권1호
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• pp.75-83
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• 2015

The applicability of oil palm biomass, EFB(Empty Fruit Bunch) as raw materials for environmental friendly packaging material, pulp mold, was evaluated in this study. The changes in the water absorption properties of pulp mold by the addition of EFB and the surface treatments with PVA and AKD were analyzed by measuring the changes in the water absorption rate and the water contact angle. The each pulp mold sample was prepared by using laboratory wet pulp molder. And the water absorption rate of each samples were evaluated by measuring times for the absorption of a 0.1 ml water drop on the pulp mold sample surface. The addition of EFB to the pulp mold made of OCC resulted in the decrease of water absorption rate and the increase in the water contact angle. The surface treatments with PVA and AKD on the OCC pulp mold showed the significant reduction in the water absorption rate. However, in case of ONP pulp mold, the addition of EFB and the surface treatments with PVA and AKD showed no big changes in water absorption times. Those might be come from the finer surface structure of ONP pulp mold which were made of more finer and flexible fibers and more hydrophilic fibers. The results of this study showed the functional properties such as water absorption rate, could be controlled by the application of EFB and the treatments with AKD or PVA, especially in case of the OCC pulp mold.

• 한국환경생태학회지
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• 제15권3호
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• pp.207-212
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• 2001

구상나무의 묘목을 이식하여 활착률을 높이는 방법을 찾고자, 한라산국립공원 어리목대피소(해발 900m)에서 양묘된 2~6년생 묘목을 식재시기별(하기와 춘기), 지표처리별(코이어 매트. 코이어 네트 및 무처리)로 시험식재하고 활착률과 신초생장량을 조사.비교하였다. 하기식재의 경우 묘목의 연령이 높을수록 활착율이 높았으며, 지표처리에 따른 차이는 없었다. 춘기식재의 경우에는 묘목의 연령이 낮을수록 활착률이 높았으며, 지표처리 및 차이는 없었다. 하기식재된 구상나무 묘목의 신초생장에 있어서는 지표처리의 효과가 통계적으로 인정되었다. 코이어 매트를 처리한 시험구가 평균 2.11mm로 가장 많이 성장하였고, 대조구는 평균 1.47mm 성장하는 데 그쳤다. 묘령은 신초생장에 영향이 없었으며. 상대적으로 3년생 묘목을 코이어 매트 처리한 경우가 2.26mm로 가장 잘 자랐다. 춘기식재된 구상나무 묘목의 신초생장에 있어서는 지표처리나 묘령의 통계적 유의성은 인정되지 않았다.

• 한국전기전자재료학회논문지
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• 제22권6호
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• pp.532-536
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• 2009

In this study, the capacity change of supercapacitor was investigated by surface treatments of carbon nanotubes as electrode materials with various methods, such as ball-milling, $KMnO_4$ and $H_2SO_4/HNO_3$ acid mixture. Surface treatments generated a number of defects on the surface of carbon nanotubes by attacking on $\pi$ bond in graphene layer, at which carboxyl groups were introduced. These hydrophilic groups could enhance the capacity by increasing the wettability of carbon nanotube surfaces. However, a drawback of the surface treatment was the decrease of conductivity by the loss of conduction path in graphene layer due to the defect formation. The surface treatment condition should be therefore optimized between hydrophilicity increase and conductivity decrease.

• 한국농공학회지
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• 제42권
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• pp.38-49
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• 2000

Two application rates (9 and 18 t/ha) of poultry litter and a recommended rate of commercial fertilizer were studied to determine their effects on nutrient (N and P) losses in surface and subsurface runoff and loadings in soil layers from conventionally-tilled com by the treatments. The model predicted higher sediment losses than observed data from all treatments. The overpredicted sediment losses resulted in overprediction of organic-N and sediment-P losses in surface runoff. Simulated soluble-P losses in surface runoff were close to observed data, while NO3-N losses in surface runoff were underpredicted from all treatments. Observed NO3-N concentrations in leachate at 1.0-m depth from commercial fertilizer treatment were fairly well predicted. But the concentratins were overpredicted from poultry litter treatments due to high simulation of organic-N mineralization simulated by the model.

• Bulletin of the Korean Chemical Society
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• 제18권7호
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• pp.737-740
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• 1997

The influence of cyclic treatments with H2O2/DIW (1 : 10) and HF/DIW (1 : 100) on the roughness of silicon surface in the wet chemical processing was investigated by atomic force microscopy (AFM). During the step of the SC-1 cleaning, there is a large increase in roughness on the silicon surface which will result in the poor gate oxide breakdown properties. The roughness of the silicon wafer after the SC-1 cleaning step was reduced by cyclic treatments of hydrogen peroxide solution and hydrofluoric acid solution instead of HF-only cleaning. AFM images after each step clearly illustrated that the average roughness of silicon surface after three times treatments with H2O2 and HF solutions was reduced by 10 times compared with that after the SC-1 cleaning step.

• 대한치과기공학회지
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• 제41권3호
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• pp.177-185
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• 2019

Purpose: This study was to investigate the effect of three different surface treatments on the shear bond strength of lithium disilicate ceramics to enamel. Methods: Totally 60 lithium disilicate ceramic disc specimens were fabricated with IPS e.max press (Ivoclar Vivadent, Schaan, Liechtenstein) and Mazic Claro (Vericom, Korea). 30 specimens in each lithium disilicate ceramic were assigned to 3 groups of the each following surface treatment: 1) $50{\mu}m$ airborne particle abrasion+silane, 2) 9.5% hydroflouric acid etching (HF)+silane, 3) $50{\mu}m$ airborne particle abrasion+9.5% HF+silane. Lithium disilicate ceramic surfaces after surface treatments were AFM examined. The shear bond strength was measured in a universal testing machine at 0.5mm/min crosshead speed. All data were analyzed using a two-way ANOVA and Tukey's test(${\alpha}=0.05$). Results: The mean surface roughness of lithium disilicate ceramics ranged from $0.178{\mu}m$ to $0.441{\mu}m$. The mean shear bond strengths ranged from $23.81{\pm}2.78MPa$ to $33.99{\pm}4.85MPa$. Conclusion: 1. Mazic Claro showed higher shear bond strength than IPS e.max press at 3 different surface treatments, and no statistically significant was observed. 2. The shear bond strength of IPS e.max press was strongly enhanced as surface treated with $50{\mu}m$ airborne particle abrasion and 9.5% hydroflouric acid etching. And there was no statistical significance at the shear bond strength of Mazic Claro with surface treatments.

• The Journal of Advanced Prosthodontics
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• 제8권5호
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• pp.339-344
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• 2016

PURPOSE. Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disilicate (LD) after various pre-surface treatments. MATERIALS AND METHODS. Thirty-two (n = 32) discs were prepared for each coping material. Four pre-surface treatments were prepared for each sub-group (n = 8); a) no treatment or control (C), b) sandblast (SB), c) acid etch (AE), and d) sandblast and acid etch (SBAE). Veneering ceramics were applied to all discs. Shear bond strength was measured with a universal testing machine. Data were analyzed with two-way ANOVA and Tukey's multiple comparisons tests. RESULTS. Mean shear bond strengths were obtained for MA ($19.00{\pm}6.39MPa$), ZO ($24.45{\pm}5.14MPa$) and LD ($13.62{\pm}5.12MPa$). There were statistically significant differences in types of coping material and various pre-surface treatments (P<.05). There was a significant correlation between coping materials and pre-surface treatment to the shear bond strength (P<.05). CONCLUSION. Shear bond strength of veneering ceramic to zirconia oxide was higher than metal alloy and lithium disilicate. The highest shear bond strengths were obtained in sandblast and acid etch treatment for zirconia oxide and lithium disilicate groups, and in acid etch treatment for metal alloy group.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.229.1-229.1
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• 2010

We investigated the effect of chemical acid treatments on hydrogen storage behaviors of the ordered mesoporous carbons (MCs). The surface functional groups and specific elements of the MCs were characterized with Fourier Transform Infrared (FT-IR) spectrometry and X-ray photoelectron spectroscopy (XPS). Also, the changes in the surface functional groups of the MCs were quantitatively detected by Boehm's titration method. The structural properties of the MCs were investigated using X-ray diffraction (XRD). The hydrogen adsorption capacity of the MCs was evaluated by means of adsorption isotherms at 77 K/1 bar. The formation of surface functional groups by the acidic treatments could influence on the hydrogen storage capacity of the MCs.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.362-362
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• 2006

Chromic acid anodizing of aluminium is an effective process for producing a substrate which provides excellent surface properties to assembly. However, new chromium-free finishing metal treatments are being developed to reach new environmental goals. Present study deals with chromium free experimental conditions for both deoxidizing and anodizing treatments. Results clearly demonstrate the potentiality for environmentally friendly treatments to get suitable metal-adhesive performance. In particular, the role of both metal surface porosity and chemical composition has been highlighted thus allowing to propose alternative to classical treatments for aeronautic applications.

• Journal of Acupuncture Research
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• 제29권4호
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• pp.55-69
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• 2012

Objectives : The aim of this study was to compare the effects of 12 acupuncture treatments versus 24 acupuncture treatments for patients with dry eye syndrome. Methods : We have assessed the symptom score, number of dry eye symptoms, and ocular surface disease index(OSDI) scores before and after the acupuncture treatments. The group A received 12 acupuncture treatments, and the group B received 24 acupuncture treatments. To evaluate the efficacy of acupuncture treatments the before and after scores of both groups were compared. Results : After treatment, symptom score, number of dry eye symptoms, and ocular surface disease index(OSDI) were significantly decreased in each group (p<0.001). The symptom score has shown a greater decrease in group B than group A, but no significant differences were seen in the numbers of existing symptoms and ocular surface disease index(OSDI) scores between the two groups. Conclusions : Acupuncture is an effective way to relieve the symptoms of dry eye syndrome. The more number of acupuncture treatments may be correlated with better outcomes in the means of symptom score.