• Transactions on Electrical and Electronic Materials
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• 제17권3호
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• pp.134-138
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• 2016

The fullerene solar cells are becoming a feasible choice due to the advanced developments in donor materials and improved fabrication techniques of devices. Recently, sufficient optimization and improvements in the processing techniques like incorporation of solvent vapor annealing (SVA) with additives in solvents has become a major cause of prominent improvements in the performance of organic solar cell-based devices . On the other hand, the challenge of reduced open circuit voltage (V_oc) remains. This study presents an approach for significant performance improvement of overall device based on organic small molecular solar cells (SMSCs) by following a two step technique that comprises thermal annealing (TA) and SVA (abbreviated as SVA+TA). In case of exclusive use of SVA, reduction in V_oc can be eliminated in an effective way. The characteristics of charge carriers can be determined by the measurement of transient photo-voltage (TPV) and transient photo-current (TPC) that determines the scope for improvement in the performance of device by two step annealing. The recovery of reduced V_oc is linked with the necessary change in the dynamics of charge that lead to increased overall performance of device. Moreover, SVA and TA complement each other; therefore, two step annealing technique is an appropriate way to simultaneously improve the parameters such as V_oc, fill factor (FF), short circuit current density (J_sc) and PCE of small molecular solar cells.

• 대한환경공학회지
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• 제36권12호
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• pp.851-857
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• 2014

본 연구에서는 해양오염퇴적물의 유기 오염물질을 제거하기 위한 세척기반처리 공정 중 중금속 특히 생물이용이 가능한 중금속 부분(Bioavailable Heavy Metal)의 동시 처리 가능성에 대해 평가하였다. 해양오염퇴적물 정화사업 대상인 N해역에서 퇴적물을 채취하여 본 연구의 시료로 사용하였다. 세척기반처리 공정에서 첨가제로는 산화제인 과산화수소($H_2O_2$)와 비이온 계면활성제(Tween-80)를 사용하였다. 퇴적물과 해수의 고액비는 1 : 3이며 과산화수소의 농도 1 M, 3 M, 4 M, 5 M과 0.05% Tween-80을 첨가하여 각 반응 시간(10, 20, 30, 40, 50, 60, 70, 80분, 24시간) 조건에서 시험하였다. 그 결과 총유기탄소(Total Organic Carbon, TOC) 제거 효율은 5 M + 0.05% Tween-80 24시간에서 최대 55.2%로 나타났다. 중금속 총 함량(Total Heavy Metals)은 구리(Cu), 아연(Zn), 카드뮴(Cd) 각각 29.5, 42.3, 73.0%의 제거 효율로 5 M + 0.05% Tween-80 10분에서 가장 좋은 제거효율을 보였다. 생물이용이 가능한 중금속 부분의 경우도 Cu, Zn, Cd에서 각각 60.0, 77.7, 90.2%로 5 M + 0.05% Tween-80 10분에서 가장 좋은 효율을 나타내어 유기물 처리 공정에서의 Cu, Zn, Cd 등 일부 중금속의 동시 제거 가능성을 확인하였다. 총유기탄소 함량과 생물이용이 가능한 중금속 부분의 상관분석 결과 제거 된 Cu, Zn, Cd은 $r^2$값이 0.94, 0.85, 0.69로 좋은 상관관계를 보여주었다.

• 유기물자원화
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• 제24권3호
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• pp.91-99
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• 2016

본 연구는 어분을 이용하여 액비를 제조할 때 발효 미생물 및 당밀 첨가, 그리고 어분 농도에 따른 액비의 특성 변화를 구명하고 어분액비 시용이 오이 생육에 미치는 영향을 검토하고자 수행하였다. 액비 제조 시 발효미생물로 건조효모를 첨가하였을 때 pH와 EC 값의 변화가 컸으며 $NH_4-N$농도는 가장 높았다. 당밀 첨가구가 무첨가구에 비해 액비의 pH가 낮았으며 EC, $NH_4-N$, $P_2O_5$농도는 당밀 첨가에 따른 차이를 보이지 않았다. 어분농도에 따른 액비 특성은 20% 어분 첨가구의 pH가 가장 높았으며 EC농도는 어분농도가 증가할수록 높아졌다. 액비의 $NH_4-N$ 함량은 발효 후 20% 어분 첨가구가 가장 높게 나타났다. 제조한 액비시용에 의한 오이생육은 화학비료구와 비교하여 생육 차이는 없었으며 오이수량은 생육기간 동안 공급된 질소량에 의한 차이를 나타냈다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.73-76
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• 1999

In recent, concrete material like specific cement and additives having many functions hsa been developed. In road pavement, ultra high early strength cement or organic material are used to open the road early, but there are many restrictions like workable time and special equipment. We aim to developed specific concrete which 1 day strength is over 300kgf/$\textrm{cm}^2$ to open the road within one day and workable time is maintained over 1 hour that can make the concrete ready mixed concrete. In this study, we are convinced if the ratio of hauyne clinker or its additive is increased early strength property is progressed and if the ratio of non hydrous gypsum is increased longtime strength is progressed. The concrete strength is 290-310 kgf/$\textrm{cm}^2$ at 1 day, 570-640 kgf/$\textrm{cm}^2$ at 28 day and the workable time is maintained over 30 minutes. As the results of this experiments We find out the possibility to developed the 1 day usable ready mixed concrete with high early strength.

• Preventive Nutrition and Food Science
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• 제17권1호
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• pp.46-52
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• 2012

This study was performed to investigate the effects of pre-treatment and storage temperature and periods on the quality characteristics of ginger paste. The pH of the ginger paste remained constant during room temperature storage but increased with prolonged refrigerated storage periods. During five months of frozen storage, regardless of pre-treatment, the pH of most of the samples decreased slightly and then remained constant. In the color value of ginger paste stored at room temperature, the samples with and without chemical additives changed in color more prominently than fermented or pasteurized samples. Intriguingly, the color value for samples containing chemical additives changed more dramatically when stored under refrigerated conditions. However, the L, a, and b values of samples stored under frozen storage conditions did not change even after ten months. Most of the samples contained glucose and fructose, except for the fermented samples. The free sugar content of samples slowly decreased with increasing storage periods, while the organic acid content generally decreased also, regardless of sample type. Depending on pre-treatment and storage temperature, the gingerol content of the samples was either retained or decreased with prolonged storage time.

• 대한화학회지
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• 제26권3호
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• pp.135-141
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• 1982

일산화탄소를 생성시키기 위한 이산화탄소의 감마선 분해반응(총흡수선량 6.7 Mrad)에서 몇가지 유기물의 첨가효과를 연구하였다. 순수한 이산화탄소를 조사할 때는 일산화탄소가 생성되지 않았으나 첨가제를 가한 경우 상당량의 일산화탄소가 생성되어 0.5%의 메탄올 및 0.25%의 에탄올의 첨가에 의해 각각 4.1 및 4.6의 최대G(CO)값을 얻었다. 또 1%의 포름알데히드 첨가에 의해서는 가장 높은 수율인 8.4의 G(CO)값을 보였고, 1% 아세트알데히드의 경우는 6.3의 G(CO)값을 보였으며 40 Mard에서 최대일산화탄소농도 0.65%를 얻었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.699-704
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• 2001

Until recently, disposal to landfill has been the most convenient way to deal with the increasing amount of residues the shredding industries produce. But the shortage of such disposal sites and the risk that liquid drained from these waste dusts may pollute ground water have increased the environmental pressures to find more effective solutions. The present study is an alternative approach that suggests identifying waste dusts characteristics and selecting an appropriate binder for hazardous materials to reduce the amount of contaminants (mainly lead) that were leaking into the soil. Investigations on the characteristics of automobiles waste dusts show that these materials are composed mainly of cottons and sponge like substances, plastics, rubber, glasses and gravel, metals, and electric wires. Besides, the percentage in weight of organic (inflammable) materials is about 70% and the lead contamination, which has not a ionic but a particulate nature, is particularly remarkable in cottons and sponge like materials. Binding additives such as K-20 and sodium carbonate were not effective but the addition of 5 % of cement (in weight of the investigated sample) followed by a 3-minute stirring and a 4-hour storage could drastically reduce the run off of lead below the maximum authorized level. No addition of water was necessary in this method.

• 멤브레인
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• 제5권1호
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• pp.44-57
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• 1995

내부산의 탈거제로 탄산나트륨을 함유하는 유화액막의 거동을 묘사하기 위하여 수학적 모델이 제시되었다. 젖산의 회분식 추출 실험 결과가 모델의 계산 결과와 비교되었는데, 모델의 계산 결과는 담체농도, 탈거제농도, 교반속도, 처리비와 같은 변수의 영향을 잘 예측할 수 있었다. 유화액막의 주요 문제 중의 하나인 에멀젼의 팽윤을 줄이기 위하여, 액체 파라핀, n-데칸올, 사이클로헥사논, 스판-85 같은 막 첨가제가 사용되었다. 사용된 모든 첨가제는 팽윤 정도를 줄이는데 어느 정도 효과가 있었다. 사이클로헥사논은 팽윤을 줄일 뿐만 아니라, 젖산의 전달 속도를 크게 증가시키는 것으로 관찰되었다.

• 펄프종이기술
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• 제43권3호
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• pp.21-29
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• 2011

Recently, the use of recycled fibers was increased in order to replace the virgin pulp for low production cost and forest conservation. However, the recycled fibers decreases drainage rate, papermaking efficiency and product quality by short fibers and low wettability because of hornification. To overcome the limitation of low drainage rate, the technology of organic fillers were applied. Wooden fillers gave high bulk and stiffness of paper, but they reduced the strength of paper. In order to improve strength properties 4 types of strength additives were added and analyzed. Cationic starch, branched strength additive, linear wet strength additive, and linear dry strength additive were used. The drainage rate and paper properties such as bulk, air permeability and tensile strength were measured. As results of analysis, addition of branch type of strength agent such as C-starch was effective than linear type of strength agent in the drainage rate. Nevertheless there was no effect on the drainage rate by adding the pretreated wooden fillers. By adding the pretreated wooden fillers, bulk, air permeability and tensile strength of handsheets were improved with low dosage than non-pretreated fillers.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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• pp.47-48
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• 2011

The effect of solution acidity and organic additives, polyethylene glycol (PEG), on the trivalent chromium electroplating was systematically investigated in the view point of solution stability, electroreduction of trivalent chromium ions and characterization of deposition layer. It was found that, the concentration of fraction chromium complexes in the trivalent chromium bath containing formic acid is strongly depended on pH value. PEG molecules were stable in trivalent chromium bath containing formic acid via studies on electrospray ionization mass spectrometry (ESI-MS) and UV-Vis. However, the presence of PEG molecules decreased the reductive current of hydrogen evolution, increasing of current efficiency higher about 10 % compared with solutions without PEG. Moreover, PEG additives developed the nodular morphology during electroreduction of trivalent chromium ions with the increase of solution acidity and enhanced its current efficiency by maintaining the consumption of complexant, formic acid, at a low speed. In this study, the effect of solution acidity was emphasized important, there, it controlled the formation of complexes in the solution, cathodic film (CF) during deposition, and properties of deposited layer. By electrochemical quartz crystal microbalance (EQCM), studies show that chromium electrodeposition occurs via the formation of intermediate complexes and adsorption on the cathode surface, which hinder the penetration of ions from bulk solution to the cathode surface.