• 한국의류학회지
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• 제5권1호
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• pp.15-21
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• 1981

The effect of fatty acid content in oily soil and conditions of washing on the removal of triglyceride have been studied. Cotton lawn was soiled with the four-component soil-tripalmitin, palmitic acid, dodecyl alcohol and dodecane-and washed in constant temperature waterbath shaker. The detergency was estimated by analysis of triglyceride labelled carbon-14 on fabrics before and after washing by means of liquid scintillation counting. It was shown that the detergency of triglyceride washed with the nonionic, nonylphenol poly (10)-ethylene oxide and soap was increased steadily with increasing temperature, whereas with the anionics Na-DBS and SLS, the detergency was rather decreased when the temperature was elevated above $40^{\circ}C$. To investigate the effects of free fatty acid content in soil on the removal of triglyceride, the fabrics were soiled altering palmitic acid content, and then washed. From the results, the detergency of triglyceride was developed with increasing free fatty acid content. With soils containing less than $30\%$ of free fatty acid, of the three detergents tested, the nonionic was by far the most effective soil removal. Soap was intermediate and the synthetic anionic was the poorest. With soil containing $45\%$ of free fatty acid, soap was the most effective soil removal. When NaOH was added to detergent solution. the detergency of triglyceride was improved without regard to detergents. The optimum alkalinity was obtained according to free fatty acid content. And the alkalinity changed to low NaOH concentration with increasing free fatty acid content. From the results mentioned above, it could be concluded that the major removal mechanisms of triglyceride containing oily soil were mesomorphic phase formation, solubilization and soap forma-tion when alkali was added in detergent solution.

• 한국수산과학회지
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• 제31권3호
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• pp.399-408
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• 1998

미역과 큰다시마에서 추출한 수용성 알긴산 및 산$\cdot$알칼리가용성 알긴산과 그 염산부분가수분해에 의하여 얻어진 저분자화 알긴산 (저분자화 범위 : 미역 약 4,000 kDa$\to$약 38kDa; 큰다시마 약 1.283kDa$\to$약 341 kDa과 약 45kDa)을 함유한 실험사료를 횐쥐 (SD계, 4주령)에 4주간 급이했을 때의 혈청 및 간장지질 콜레스테롤 수준 및 지방산 조성에 미치는 영향을 실험$\cdot$검토하였다. 알긴산의 급이는 식이효율이 $0.37\~0.44$로서 기초식이군에 비하여 $0.03\~0.05$ 정도 낮은 값을 보였고, 콜레스테롤 급이에 의한 간의 중량 증가도 유의적으로 억제하였다. 수용성 알긴산은 산$\cdot$알칼리가용성 알긴산에 비하여 혈청 및 간장지질 중의 총콜레스테롤, 유리콜레스테롤, LDL-콜레스테롤, triglyceride및 인지질에 대하여 현저한저감효과를 보였다. 그리고 각각의 효과는 저분자화에 의하여 현저히 증대되었다(저분자화에 의한 저감효과 수용성 알긴산 - 혈청지질: 총콜레스테롤 $59\%$, 유리콜레스테롤 $65\%$, LDL-콜레스테롤 $96\%$, triglyceride $50\%$, 인지질 $36\%$, 간장지질: 총콜레스테롤 $42\%$, 유리콜레스테롤 $62\%$, LDL-콜레스테롤 $44\%$, triglyceride $33\%$, 인지질 $44\%$ 산$\cdot$알칼리가용성 알긴산 - 혈청지질: 총콜레스테롤 $52\%$, 유리콜레스테롤 $97\%$, LDL-콜레스테롤 $78\%$, triglyceride $32\%$, 인지질 $64\%$, 간장지질. 총콜레스테롤 $11\%$, 유리콜레스테롤 $12\%$, LDL-콜레스테롤 $10\%$, triglyceride $27\%$, 인지질 $21\%$) 저분자화 알긴산의 급이가 혈청 및 간장지질 구성지방산의 조성에 미치는 효과는 콜레스테롤 급이군에 비하여 polyene산의 함유비율을 혈청지질에 있어서는 약 $44\%$이상, 그리고, 간장지질에 있어서는 약 $70\%$ 이상으로 각각 증가시켰다. 이상의 결과에 비추어 저분자화 알긴산의 급이는 실험동물의 혈청 및 간장지질 조성을 생리적으로 개선하는데 그 효과가 현저함을 뒷받침하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.280-280
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• 2007

Lead oxide-based ferroelectrics are the most widely used materials for piezoelectric actuators, sensors and transducers due to their excellent piezoelectric properties. Considering lead toxicity, there is great interest in developing lead-free piezoelectric materials, which are biocompatible and environmentally friendlier. Recently alkali oxide materials, including sodium - potassium niobate (NKN), have been given attention in view of their ultrasonic application and also as promising candidates for piezoelectric lead-free system. However, it is difficult to sinter such NKN-based materials via conventional sintering process. In this reason, many researchers have investigated hot press, hot isostatic press or spark-plasma sintering of NKN-based ceramics. In this study, as candidates for lead-free piezoelectric materials, dense (Na,K,Li)(Nb,Sb)$O_3$ systems were developed by conventional sintering process. The microstructures and piezoelectric properties of the (Na,K,Li)(Nb,Sb)$O_3$ systems were investigated as a function of variable compositions. The excellent piezoelectric and electromechanical properties indicate that this system is potentially good candidate as lead-free material for a wide range of electro-mechanical transducer applications.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.423-429
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• 2008

석탄을 가스터빈에 직접 사용하여 발전 효율을 높이고자 용매추출법으로 회분이 제거된 청정석탄 제조공정이 개발되고 있다. 용매추출에 의해 생산된 청정석탄에는 미량의 알카리금속이온이 들어있어서 연소시에 터빈 날개의 부식을 일으킬 수 있다. 이 연구에서는 청정석탄 제조공정의 알카리금속이온 제거를 위하여 무기이온교환제인 ${\alpha},{\beta}$-인산금속 산화물들(ZP: $Zr(HPO_4)_2$, TP: $Ti(HPO_4)_2$, ZTP: $ZrTi(HPO_4)_4$, Z1TP3: $Zr_{0.25}Ti_{0.75}(HPO_4)_4$, Z3T1P: $Zr_{0.75}Ti_{0.25}(HPO_4)_4$)과 H-Y 제올라이트를 제조하여 수용액 및 석탄이 용해된 고온의 유기용매(N-methyl-2-pyrrolidone)에서 나트륨 이온 제거 특성을 비교 분석하였다. ${\beta}$ 형태의 인산금속산화물들은 모사 수용액($Na^+$ Conc. 100 ppmw)에서 ${\alpha}$ 형태에 비해 높은 이온교환용량을 가지고 있으며 H-Y 제올라이트에 비해서도 높은 나트륨 이온 제거용량을 보여주었다. 이온교환매체가 고온의 유기용매($Na^+$ Conc. 12 ppmw in NMP)일 경우에는 H-Y 제올라이트의 나트륨이온 제거율은 $300^{\circ}C$까지 90% 이상이었으나, 그 이상의 온도에서는 50% 가량으로 급격히 감소하는 경향을 보여주었다. 그러나 ${\beta}$ 형태의 인산금속산화물들은 여러 온도조건($250{\sim}400^{\circ}C$)에서 90% 이상의 제거율을 나타내었고 강산용액을 이용한 재생 후에도 최초 실험과 유사한 나트륨 이온 제거율을 보여주었으며 그 중 가장 높은 제거율을 나타낸 $Zr_{0.75}Ti_{0.25}(HPO_4)_2$는 알카리금속이온 제거공정에 가장 적합한 무기이온교환제로 판단된다.

• 한국산림과학회지
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• 제61권1호
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• pp.27-36
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• 1983

본(本) 연구(硏究)는 질산(窒酸)펄프화법의 기술(技術)을 확립하기 위한 기초자료(基礎資料)를 얻기 위하여 실시(實施)하였다. 값이 비싸고 목재(木材)에 침투성(浸透性)이 불량(不良)한 질산(窒酸)을 직접 적용시키지 아니하고, 알카리전처리(前處理)로 어느정도 탈리그닌이 진행된 시료(試料)를 사용, 질산(窒酸)펄프화 2단증해(段蒸解)를 행하여 전처리(前處理)가 탈리그닌 및 펄프수율(收率)에 미치는 영향(影響) 및 펄프화 과정(過程)에서의 탄수화물(炭水化物)과 리그닌의 용출(溶出)거동을 구명(究明)코저 하였다. 질산(窒酸)펄프화의 제(第) 1 단증해(段蒸解)에 있어서 증해시간(蒸解時間)이 증가함에 따라 펄프수율(收率)이 감소하였으며 질산농도(窒酸濃度) 1, 2%보다 3%가 펄프수율(收率) 및 탈리그닌에 현저히 영향(影響)하였다. 또한 알카리전처리(前處理)는 질산(窒酸)펄프의 수율(收率)에 크게 영향하였으며 79%의 전처리수율(前處理收率)로서 충분한 탈리그닌 효과(効果)를 얻을 수 있었다. 질산(窒酸)펄프화 과정에서 용출(溶出)되는 탄수화물(炭水化物)은 주로 xylose였으며, 이들의 용출(溶出)은 증해시간(蒸解時間)이 증가함에 따라 증가되었는바, 이는 탄수화물(炭水化物)에 대한 질산(窒酸)의 산화작용(酸化作用)으로 도입된 carbonyl기(基)가 탄수화물(炭水化物)의 붕괴를 초래한 결과로 생각된다.

• The Korean Journal of Ecology
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• 제18권1호
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• pp.43-54
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• 1995

Effects of environmental factors of N, P, pH, moisture, temperature and oxygen on growth and nitrogen fixation activity of kummerowia striate (Thunb.) Schindler seedling, bearing symbiotic root nodules, were quantitatively analyzed during the growing period. The specific nitrogenase activity (ARA) of nodules showed the maximum value of 187 μmol C₂H₄g fr wt-1 h-1 6 weeks after seeds were germinated. The total nitrogenase activities per plant attained as 1.56, 0.85, 0.09 and 4.0, 1.11, 0.04 μmol C₂H₄hr-1, respectively for the treatments of 1, 3 and 5 mM NO₃￣and NH₄＋ on the 60th day. While the plant grown in N-free media for 20 days after treatments of 5 mM NH₄+for 40 days resulted in 30 mg fr wt of nodule formation and exhibited the relative activities of 152％ and 162％ for total and specific ARA in comparison with those of control plant grown with N-free for 60 days. Total biomass and ARA was by 70％ and 86％ lower in N and P deficiency, respectively. The N and P deficient plot showed 70％ and 86％ decreases of total biomass and ARA in comparison with those of control. The plant grown with N-free for 20 days after pretreatment with N and P free media for 40 days showed the relative values of 77％, 118％ and 150％, respectively for nodule biomass, total and specific ARA in comparison with those of control. The treatment with acid or alkali gradients resulted in significant decreases of nodule biomass and ARA. The optimum temperature and pO₂for ARA were 30°C and 40 kPa, respectively. Two peaks of diurnal variation appeared at 11:00 and 23:00 o'clocks by the continuous light condition. The plants with water stress by temporary wilting point rsulted in 95~97％ inhibition for nodule respiration, transpiration and specific ARA. Transpiration and ARA ware recovered to 88％ and 38％ of those of water unstressed plants, respectively, 6 hours after the plants were rewatered from water stressed condition.

• 미생물학회지
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• 제5권2호
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• pp.61-68
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• 1967

In the process of the incorporation of orthophsphate into protein and other cell constituents, the role of inorganic polyphosphate and RNA-polyphosphate complex and the correlation between them were pursued by analyzing the contents of $^{32}P$ and total P in various fractions of Chlorella cells, which had been uniformly labeled with $^{32}P$ before the inoculation in a normal "cold" medium or P-free medium during the culture. The effects of ionizing radiation and various micronutritional-element deficiencies on the phosphate incorporation into, and biosynthesis of, protein and other introgenus compounds in the cells were also observed. When the uniformly $^{32}P$-labeled algae were grown in a normal "cold" medium the contents of $^{32}$ P in the fractions of protein, DNA and RNA-polyphosphate complex increased, but those in the fraction of acid-insoluble polyphosphate decreased. On the other hand, amount of $^{32}P$in the fraction of RNA was almost unchanged in spite of rapid increase of the total P. In the growing period of $^{32}P$-labeled algae in a P-free medium, amounts of $^{32}P$ in the fractions of DNA, protein and lipid increased, while those in the fractions of RNA-polyphosphate and inorganic polyphosphates decreased. When the algal cells were irradiated with about 70, 000r of gamma-rays before the inoculation in the medium, amounts of phosphate in the fractions of DNA, RNA, nucleotides and protein decreased during the culture, compared with those of the control. However, the phosphate content in the fraction of acid-insoluble polyphosphate of the irradiated cells increased than those of the control. In the growing period of the algae in a Mo-free, medium, amounts of acid-soluble total phosphate and nucleotides of the cells increased, while the amounts of residual protein and RNA decresed compared with those of the normal cells. Amounts of alkali-labile protein and phospholipid of the cells grown in a B-free medium decreased, whereas amount of phosphate in acid-soluble fraction increased compared with the control. In general, the contents of protein and RNA in each microelement deficient cells decreased more or less, compared with those in the normal cells.in the normal cells.

• 한국세라믹학회지
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• 제33권4호
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• pp.385-390
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• 1996

The electrical resistivity of the ceramic glaze coated on ceramic substrate plays an important role on the characteristics of the thick and thin film electrical circuits. In this study the effects of the various modifiers on the electrical resistivity were examined in SiO2-Al2O3-B2O3-RO-Na2O (RO=CaO , SrO, BaO, PbO) glass system. In alkali free glasses where divalent cations are responsible for electrical conduction the electrical conductivity of th glasses increased with the ionic size of divalent cations due to the decrease in the bond strength between oxyben and divalent cation. In Na2O containing glasses however where Na+ ion is responsible for electrical conduction the ionic conductivity decreased with the ionic size of divalent cations because the blocking effect of the cations on Na+ ion movement increased with larger divalent cations. Na+ ionic conduction also depended on the glass structure relaxation due to the corrdination number changes of B2O3 and Al2O3 which varied with the NaO2 content in the glass.

• 한국생산제조학회지
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• 제25권1호
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• pp.14-20
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• 2016

This paper describes a green stripping process to effectively strip the remaining DFR layer on a non-alkali-based ITO glass surface after an etching process. A stripper, water-soluble amine compound, is used to investigate the characteristics of stripping ability and to suggest a valid method for the green process. Increasing the composition (5-30% concentration) of the ethanol amine-based stripper was found to greatly reduce the stripping time applied in the dipping method. The composition (30%) achieved an excellent stripping effect and free-residue impurities. Additionally, it was possible to obtain the effect of stripping in a way to sustain the release before generating DFR sludge from the ITO glass surface by using dipping condition (stripping time) in the composition. An Additional stripping process (buffering) out of dipping can realize productivity improvement and cost reduction because of the higher proportion of re-use of the stripping solution used in the DFR removal step.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.514-519
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• 2001

Converter has been slag produced 10 million tons per year in Japan. It is a steel making by product produced in the same way as the blast-furnace slag. Though blast-furnace slag is being used effectively as a concrete admixture, the converter stag has never been used effectively because of the expansion action of contained free lime and iron oxide. This is an important environmental problem in the steel industry. Beta-2CaOSiO$_2$(beta-C$_2$S) is contained 40 percent in converter slag, therefore it is very promising as a concrete admixture. We proposed an accelerated aging processes capable of stabilizing the converter slag in a short time. The converter slag is dipped into alkali aqueous solution after heating at low temperature. It was subsequently ground to a grain size of 75 ${\mu}{\textrm}{m}$ , inner 30 percent of OPC. The properties of mortar and concrete using the blended cement were determined. As a result, it has become apparent that the expansion was reduced and long term compressive strength was increased while that at early ages was not so remarkable. The hydration exotherm rate was lower than that of the OPC.