• 한국지하수토양환경학회지:지하수토양환경
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• 제9권4호
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• pp.52-61
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• 2004

음이온 비소와 양이온 아연 및 니켈로 오염된 토양을 산세척으로 복원하기 위해서 토양세척 파일럿 장비를 이용해서 토양의 물성과 산세척 특성 및 미세토양과 용존 오염물의 발생 특성을 고찰하였다. 비소와 아연 및 니켈의 pH $2{\sim}3$에서 산세척시 황산과 인산은 공존 경쟁 음이온의 존재로 비소의 제거 효율을 높였고, 염산은 비소, 니켈, 아연을 동시에 효율적으로 제거하였다. 세척조에서 화학적 용출은 임계체류시간 이상에서 세척 효율이 일정해졌고, 산에 의한 용출 가능한 존재형태는 교환성 및 산화물 결합과 유기성 결합형태, 그리고 부분적으로 잔류형태였다. 오염 토양의 입도에 따른 과립의 토양입자의 토양세척 효율은 높지만, 미세입자($<74{\mu}m$)는 오염물질의 농집 현상이 일어나서 제거효율이 감소했다. 또한, $<149{\mu}m$ 이하의 미세토양을 물리적 입도 분리시 전체 세척효율이 향상되었다. 따라서, 미세토양의 양이 최소가 되고 화학적 용출이 최대가 되는 세척 효율 교차지점에서 화학적 용출과 미세토양의 분리가 토양세척의 증가된 효율을 보여 주었다.

• 가족자원경영과 정책
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• 제22권3호
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• pp.21-41
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• 2018

This study determined the characteristics of meal-related time use among employees living in one-person and multi-person households by conducting a comparison focused on gender and age differences. Among the questionnaires distributed to employees during the 2014 Korean Time Use Survey, 19,692 were used for final analysis. The results were as follows: First, the one-person households had shorter meal-related time use than did the multi-person households, except for the time spent having snacks and beverages. Second, meal-related time use was generally longer in non-working days than in workdays. Third, gender differences in meal-related time use were observed, with the more significant ones being the differences in time devoted to meal preparation and dishwashing. Fourth, in both the one-person and multi-person households, women spent a longer amount of time preparing meals and washing dishes than did men, but this difference was greater in multi-person households. Fifth, old individuals spend a longer time preparing meals and washing dishes than did young individuals. Policies must be enforced to improve the quality of diets in one-person households. Such households should also be provided nutrition education to increase their awareness of the importance of healthy and regular meals. Another essential requirement of policy is the provision of gender equality education for both the one-person and multi-person households.

• 유기물자원화
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• 제25권3호
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• pp.63-71
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• 2017

본 연구에서는 활성탄 제조에 널리 이용되고 있는 KOH 활성화법으로 활성화된 활성탄의 표면적 증가를 위하여 세척시간, 교반속도, 세척횟수 등의 변수들에 대한 활성탄 세척공정 최적화 연구를 수행하였다. 연구결과, 활성탄의 표면적은 세척효율이 증가됨에 따라 뚜렷하게 증가되었는데, 90% 이상의 세척효율을 얻기 위해서는 활성탄의 복잡한 세공구조에 따른 세공 내 확산메커니즘이 제어인자로 작용함을 알 수 있었다. 또한, 세척액의 증발을 통하여 $K_2CO_3$를 얻을 수 있었고 이를 이용한 활성화실험이 이루어졌다. 그 결과, 비표면적 $2,219m^2/g$의 제조가 가능하였다. $K_2CO_3$가 KOH의 효과적인 대안이라는 것을 고려할 때, 활성탄 제조공정에서 폐수 재이용은 무배출 폐기물 공정에 적용 할 수 있음을 보여주었다.

• 한국식품과학회지
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• 제33권2호
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• pp.205-208
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• 2001

맥주 공장 부산물인 맥주효모 슬러리의 쓴맛을 제거하기 위하여 가성소다 액을 이용한 세척 시험을 하였다. 효모 슬러리를 묽은 가성소다 액에 침지시키고 세척함에 따라 쓴맛이 감소하였는데, 가성소다 액의 농도를 0.05%(w/v)에서 0.25%(w/v)로 단계적으로 증가시킴에 따라 맥주 효모의 쓴맛 정도(bitterness unit)가 45 BU에서 3.0 BU까지 낮아진 반면 효모가 폐사되는 단점이 나타났다. 쓴맛 제거 정도와 세척 효모의 생존율을 동시에 고려할 때 $0.07{\sim}0.1%$(w/v) pH로는 $9.5{\sim}10.5$인 가성소다 액에 효모 슬러리를 넣고 $10{\sim}20$분 방치한 다음 0.85%(w/v) NaCl 용액으로 세척하는 것이 가장 좋은 것으로 나타났다. 세척된 효모 슬러리는 세척 전보다 백색(whiteness)이 증가되었으며 황색(yellowness)은 감소하였다. 이외에도 알코올 용액을 사용하여 세척해도 우수한 쓴맛제거 효과를 얻을 수 있었다.

• 한국염색가공학회지
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• 제18권4호
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• pp.11-19
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• 2006

Black-dyed PET fabrics were sputtered with stainless steel through DC-magnetron type device to investigate the possibility of coloration effect, and then considered the morphological structure and physical characteristics such as water permeation ability and washing fastness. Change in color was estimated on the basis of CIELAB color system. The color coordination of metal plated PET was shifted to yellow-red from red-blue. Colour difference$({\Delta}E^*)$ was increased by sputtering conditions with increasing ion current and treatment time. Especially, $Lightness(L^*)$ value of PET was remarkably increased by sputtering, whereas $Chroma(C^*)$ increased gradually. From SEM analysis, rough and uneven craters were found and thickened on the fiber surfaces with longer sputtering time. And washing fastness was a little poor and absorption ability slightly decreased. There were little changes of breaking load and breaking extension. It was evident that observed uneven craters in the plated thin layer resulted in the colour change of PET fabrics by sputtering treatments.

• 한국염색가공학회지
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• 제17권1호
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• pp.1-6
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• 2005

This study were carried out to investigate the effects of mordants and mordanting methods under the various dyeing conditions such as temperature, time, pH, repetition of dyeing in the silk fabrics with Petasites japonicus leaf. It was the most high K/S values of the silk fabrics dyed with Petasites japonicus leaf according to co mordanting and used cupric sulfate, ferric sulfate as mordanting agents. K/S values of the silk fabrics dyed with Petasites japonicus leaf were increased gradually with dyeing temperature, dyeing time, repetition of dyeing was higher and the optimum pH was pH 7. Silk fabrics were colored yellowish orange and surface color(munsell value) was changed from 8.3YR to 2.0Y by using mordanting agents and those of the silk showed high tone when mordanting with cupric sulfate but decolored and darked when mordanting with ferric sulfate. Washing fastness of silk fabrics were good in 4 ～ 5 grade, so washing fastness of the silk fabrics was significantly improved when washed with the neutral detergent.

• 한국생활과학회지
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• 제19권4호
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• pp.709-717
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• 2010

This study investigated the properties and functions of wool and silk dyed with Catechu by examining the effects of dying conditions such as dye concentration, dying temperature, dyeing time, pH level and pre-mordants. These conditions were examined in relation to dye uptake and color changes, washing fastness, light fastness, ultraviolet-cut ability and antimicrobial ability of the dyed fabrics. Catechu showed good affinity to silk fiber. Langmuir adsorption isotherm was obtained, and so it was considered that ionic bondings are formed between Catechu and protein fiber. As the dyeing time and temperature is increased, the dyeability of both silk and wool fabrics also increases. At high temperatures the color of dyed fabrics changes from Y and YR to R. Wool is effective in using Al, Cu, Fe mordant, while silk is effective only in using only Cu mordants. The dyeability was shown to be improved at low pH levels. Additionally, both washing fastness and light fastness were shown to be low. However, the fabric color gradually changed to red was due to mailard reaction of catechol tannin causingby repeated washing and sunlight. The ultraviolet-cut ability was improved for cotton fabric dyed with Catechu. Also, dyed fabric with Catechu showed very good antimicrobial abilities at 99.9%.

• 한국의류학회지
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• 제28권3_4호
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• pp.444-451
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• 2004

This study was carried out to investigate the chemical and dyeing properties of Petasites japonicus leaf extract under the various extracting and dyeing conditions such as temperature, time, the ratio of water and pH, repetition of dyeing in silk and cotton fabrics with Petasites japonicus leaf. The results were as follows: 1. It was found that λ$_{\max}$ of color solution extracted by Petasites japonicus leaf has two peaks at 290nm and 323nm. 2. The optimum extracting conditions were studied at 10$0^{\circ}C$, 40min., pH 7 and 1 : 20(the ratio of water and Petasites japonicus leaf), the optimum dyeing temperature, dyeing time, dyeing pH and repetition of dyeing were 10$0^{\circ}C$, 60min., pH 7, repetitions of three times, respectively. 3. Silk and cotton fabrics dyed with Petasites japonicus leaf extract were colored yellowish orange. The colory Petasites japonicus leaf extract in silk and cotton fabrics were deeped by same-mordanting with aluminum potassium sufate and cupric sulfate. 4. Washing fastness of silk fabrics was 4∼5 grade, but cotton fabrics was 3∼4 grade, so washing fastness of silk fabrics washed with neutral detergent was excellent.

• Journal of Biosystems Engineering
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• 제38권3호
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• pp.180-184
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• 2013

Purpose: This study explored the factors influencing heating value in the process of torrefaction of water hyacinth. Methods: Torrefaction was applied with three temperature settings (200, 300, $400^{\circ}C$) and three time settings (1, 2, 3 h) using small electric heaters (11.3L of holding volume). This study investigated the heating values with the washing process and process factors influenced the torrefaction. In addition, this study compared the heating values in washed and unwashed samples and suggested the optimal conditions for increasing heating value. Results: Torrefaction increased the heating value by 8.18 ~ 30.04%. Comparing heating values of each condition, the optimal temperature for torrefaction was $300^{\circ}C$ and holding time was 1 hour. The washing process increased the heating value by 19 ~ 27%. The heating value of the sample treated at $300^{\circ}C$ for three hours was 4310.80 kcal/kg, which was greater than the first class wood pellet of 4300 kcal/kg. Conclusions: This study proved that the torrefaction and washing process increased the heating value of water hyacinth. Therefore, water hyacinth is expected to be an eco-friendly biomass which substitutes for wood pellet.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1126-1130
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• 1999

This paper persents an algorithm compensating for the change of tension acting on a belt which is used as a force transfer media of the induction motor that drives a washing machine. The induction motor adopted in a washing machine is operated not only for the power-transmission device, but also for the detection of clothes load. The load of clothes is determined by the duration of inertial rotation which is occurred by the induction motor during a specific time. The tension of belt also affects the determination of clothes load as another load and this change of the tension is a significant disturbance for accurate determination. This paper mentions the algorithm compensating for the amount of change in tension and the application of the algotithm proved to be effectively increasing the washing performance and reducing the noise and the vibration.