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        검색결과 70

        21.
        1999.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        운반체(감응물질)로 제 4급 인산염을 사용하여 PVC를 지지체로 하여 과염소산이온의 농도 10-6 M까지 선형적인 이온선택성 전극을 제작하였다. 운반체의 화학적구조와 함량 가소제의 종류 및 막 두께에 따른 전극의 기울기 선형응답범위 및 한계측정농도 등 전극전위특성을 고려하여 최적의 과염소산 이온선택성 PVC막 전극을 제조한 다음 측정 가능한 pH 범위 선택계수 및 전극의 교류임피던스 특성을 비교 검토하였다 운반체로 tetraoctyl-phosphonium perchlorate(TOPP) tetraphenylphosphonium perchlorate(TPPP) 및 tetrabutylphosponium perchlorate (TBPP) 등의 제 4급 인산염의 과염소산 이온 치환체를 사용하였다 알킬기의 탄소고리 수가 증가할수록 전극특성은 TBPP, 선형응답범위 10-1×10-6 M 및 한계측정농도는 9.66×10-7 M 이었으며 시판되고 있는 Orion 전극특성보다 좋은 결과를 나타내었다 전극전위는 pH3~11범위에서 ph의 영향을 받지 않았으며 CIO4 에 대한 방해이온의 선택계수 서열은 SO24 < F < Br < I 이었다 임피던스 측정결과 TOPP의 경우 등가회로는 용액저항 이중층용량과 벌크저항의 병렬 및 Warburg 임피던스의 직렬이었다 이 경우 용액저항은 거의 나타나지 않았고 확산에 의한 Warburg 임피던스는 크게 나타났으며 Warburg 계수는 1.32×1074 Ω cdot cm2/s1/2이었다.
        4,000원
        22.
        1998.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Two-component polyurethane flame retardant coatings were prepared by blending phosphate-containing modified polyesters(PMPEs) and TDI-adduct. PMPEs were synthesized by polycondensation of dimethyl phenylphosphonate, a flame retardant component, with 1,4-butanediol, adipic acid, and trimethylolpropane. The content of dimethyl phenylphosphonate was varied 10, 15, and 20wt% for the reaction. Various physical properties of these new flame retardant coatings were comparable to non-flame retardant coatings. Coatings with 20wt% dimethyl phenylphosphonate did not burn during the vertical burning test.
        4,000원
        23.
        1997.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        인산염의 첨가가 조기 및 갈치연육의 보수력 및 단백질의 용출성에 미치는 영향과 가열처리 후에 조기육을 원료로 가공한 어묵의 texture에 미치는 영향을 조사하기 위하여 인산염을 첨가하지 않은 대조구와 4종의 시판 복합 인산염을 첨가수준별로 사용했을 때의 기능적 성질을 분석 검토하였다. 연육의 보수력 및 염용성 단백질량은 조기연육에는 인산염 B(sodium poly-phosphate 50%, sodium pyro-phosphate 20%, sodium tetra meta-phosphate 20%, sodium acid pyrophosphate 5%, sodium ultra meta-phosphate 5%)를, 갈치연육에는 인산염 C(sodium poly-phosphate 40%, sodium pyro-phosphate 30%, potassium pyro-phosphate 15%, sodium tetra meta-phosphate 10%, hexa meta-phosphate 5%)를 각각 0.4% 첨가한 경우가 가장 효과적이었고 그 때의 염용성 단백질의 용출량은 조기연육이 954㎎%, 갈치연육이 686㎎%였다. 조기육을 원료로 하여 가공한 어묵의 적정 가열조건은 85℃에서 45분간 가열한 것이 조직감이 양호하였다. 한편 121℃에서 10분간 가열한 경우는 C 인산염이 다른 인산염에 비하여 어육 단백질의 열안 정성이 높은 것으로 나타났다.
        4,000원
        25.
        1995.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To investigate the antimicrobial effect of polyphosphates as a food additive, the growth and structural change of Listeria monocytogenes Scott A were examined in relation to polyphosphates concentration and incubation temperature. Up to 10,000 ppm of polyphosphates, the growth rate of strain was gradually inhibited with increasing polyphosphates concentration and decreasing the incubation temperature. Minimal inhibitory concentration of polyphosphates to the growth of strain was about 12,000 ppm. It was observed, using both scanning electron microscopy(SEM) and transmission electron microscopy(TEM), that 0.9% polyphosphates treatment was resulted in the destruction of cell wall and outflow of cell ingredients. The antimicrobial effects of polyphosphates were more effective than those of dehydroacetate and potassium sorbate at 13℃ and 4℃. The growth rate of the strain in beef was significantly inhibited by the treatment of 0.9% polyphosphates and storaged at cooling temperature.
        4,000원
        30.
        1990.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The effects of six kinds of phosphate complex on the water holding capacity (W.H.C) and protein solubility of hair tail, yellow tail runner and dried pollack meat paste were investigated and animal meat(pork, chicken and hare meat complex). The formulation of six kind of phosphate complex employed to this experiment were made by mixing several phosphate such as sodium polyphosphate, sodium pyrophosphate, sodium acid pyrophosphate, potassim pyrophosphate, sodium ultra-meta-phosphate, sodium-tetra-phosphate and monoglyceride at different mixture ratio. Among the six kinds of phosphate complex, phosphate B complex which was formulated by mixing sodium polyphosphate 40%, sodium pyrophosphate 30%, sodium tetra mata phosphate 10%, sodium ultra meta phosphate 10% was most effective on enchanging the W. H. C. and protein solubility of hair tail, yellow tail runner dried pollack meat past and in case of pork, chicken and hare meat paste. Phosphate C complex which was formulated by mixing sodium polyphosphate 50%, sodium pyrophosphate 30%, sodium tetra meta phosphate 10%, potassium pyrophosphate 10%, was more effective them other phosphate complex, and thier optimum addition level was 0.5% respectively in weight of fish meat paste. Texture characterstics such as hanrdness, cohesiveness and springiness value of Kamaboko(fish meat and pork, chicken, hare meat complex past meat product) were evaluted as best when 0.5% of phosphate B complex was added. The optimum cooking condition of Kamaboko to get good texture was heating for 20 minutes at 120℃.
        5,100원
        31.
        1990.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Influence of mixing ratio of blending oil (rice bran oil : RBD palm olein = 1 : 1, 1 : 4 mixture: w/w) and natural tocopherol, citric acid, and sodium polyphosphate on enhancement of oxidation stability of blending oil under the condition of tap water infulx(1 ml/min/200g oil) were compared by AOM test after heating these system at l80℃. In addition, the effects of tocopherol, and synergist on oxidition stability were also tested with potato chips fried with blending oil(1 : 4 mixture). The result obtained were as followes; 1. The test of RBD palm olein addition of 50% and 80% against rice bran oil on oxidation stability showed that the higher the palm olein contents in blending oil, the higher the oxidation stability. 2. The test of oxidation stability, adding l00ppm, 200ppm and 400ppm of natural tocopherol in two different types of blending oils, A(1 : 1 mixture) and B(1 : 4 mixture), disclosed that blending oil B was more positively effective, and this trend was superior at 200ppm level particularly, Furthermore, oxidation stability was enhanced remarkably upon addition of 100ppm of natural tocopherol, and 50ppm of citric acid together with 50ppm, 100ppm and 200ppm of sodium polyphosphate in general. Especially, 200ppm of sodium polyphosphate addition induced the most synergetic effect on oxidation stability showing as much as 3 times compare to control. 3. The results of oxidation stability obtained by peroxide value on potato chips fried with blending oil (1:4 mixture added tocopherol, citric acid and sodium polyphosphate and preserved at 60℃ revealed that addition of tocopherol and 50ppm of citric acid together with 200ppm of sodium polyphosphate treatment was the most synergistic coinciding with AOM test results.
        4,000원
        32.
        1989.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The oxidative stability of palm oil with moisture addition during heationg was investigated and the antioxidant effects of tocopherol, citric acid and sodium polyphosphate were evaluated. The addition of natural tocopherol up to 200 ppm level did not improve the oxidative stability of palm oil with moisture (1m1 H2O additive to 200g of oil at 180℃). The maximum antioxidant effect was observed at the Concentration of 400 ppm. Addition of citirc acid did not influence the effective concentration of tocopherol. Whereas addition of sodium polyphosphate and citric acid increased the antioxidant effect of tocopherol. The maximum synergistice effect was observed at the concentrations of 50 ppm citric acid and 50 ppm of sodium polyphosphate. Addition of 50 ppm citric acid and 50 ppm sodium polyphosphate to 100 ppm of tocopherol exceeded the antioxidant effect of 400 ppm tocopherol alone.
        4,000원
        33.
        2020.03 KCI 등재 서비스 종료(열람 제한)
        다양한 온도에서 스트루바이트(struvite, MgNH4PO4·6H2O)들이 합성 및 건조되었다. 스트루바이트의 결정화와 그 구조적 특성은 합성 온도와 건조 온도 모두에게 큰 영향을 받았다. 스트루바이트는 합성 온도 ≤30℃에서 순조롭게 형성되었으며, 결정도는 합성 온도와 역의 관계를 보였다. 또한, 스트루바이트 결정도는 건조 온도가 45℃에서 60℃로 증가함에 따라 감소되었으며, 이는 열분해로 인해 발생한 구조적 물 분자와 암 모늄 이온의 손실로 촉진되었다. 그러나 낮은 합성 온도에서 합성된 스트루바이트 일수록 높은 결정도를 가 지며, 열분해에 의한 비정질화가 억제되었다. 본 결과는 저온의 열역학적으로 안정한 조건에서 형성된 스트루 바이트는 높은 결정성을 보이며, 이에 따른 구조 안정성과 열저항성을 갖음을 입증한다.
        34.
        2019.05 KCI 등재 서비스 종료(열람 제한)
        다양한 원인에 의한 포장체에 손상이 발생하면 신속한 통행재개를 위한 급속보수가 필요하게 된다. 산화마그네슘인산염복합체의는 경화시간이 짧고, 조기 강도발현이 가능하여 급속보수재료로 적합한 특성을 갖고 있다. 연구에서는 경소마그네시아와 제1인산칼륨을 결합하여 보수재료로 개발하기 위하여 물-결합재(W/B)비, 마그네슘-인산염(M/P)비 등의 배합비를 조정하면서 경화와 강도특성을 평가하고자 하였다. 그리고 현장 적용시의 작업성을 확보하기 위하여 표준사와 일반모래에 따른 거동차이와 지연제별 특성을 평가하였다. 실험결과 물-결합재비는 35%내외와 마그네슘-인산염비는 1.0~1.2 내외가 강도측면에서 가장 적합한 것으로 분석되었다. W/B비 0.35, M/P비 1.2 변수에서 1일 강도 25.0MPa 이상 발현되어 조기 보수재료로서 활용가능성이 충분한 것으로 분석되었다. 작업시간 확보를 위해서는 붕산을 지연제로 사용하는 것이 적합한 것으로 나타났으며, 산화마그네슘의 순도는 90~95%내외가 경화시간 확보를 위해 효과적인 것으로 나타났다.
        35.
        2015.04 서비스 종료(열람 제한)
        Purpose of this study is investigates mechanical property of Chemically Bonded Phosphate Ceramic(CBPC). For the purpose of the investigation of mechanical property, compressive stress and length change ratio were evaluated. Evaluated results of compressive stress was shown that compressive stress increased depending on aging time. On the other hand, length change ratio decrease depending on aging time.
        36.
        2013.10 서비스 종료(열람 제한)
        This study investigates strength development of magnesia-phosphate cement considering curing temperature and W/B ratio. The results revealed that it showed an excellent strength development at early ago and the influence of curing temperature was within 25% on strength.
        37.
        2013.09 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to evaluate the leaching characteristics of heavy metals (Cu, Pb, Zn and Cd) in an abandoned mine soil stabilized by applying both soluble phosphates and steel slag. Leaching characteristics of heavy metals in the contaminated soils was evaluated by toxicity characteristics leaching procedure (TCLP) and Column test. After leaching batch (TCLP) and column, Pb was found that the most greatly reduced by immobilized. Among the tested three phosphates (Na2HPO4·12H2O, Ca(H2PO4)2·H2O, (NH4)2HPO4), the leaching concentration of Ca(H2PO4)2·H2O and (NH4)2HPO4 decreased more than those of Na2HPO4·12H2O. The rate constant (k1) value was found to be about 1.5 ~ 2.0 times higher than ever before, it could be fast immobilized. The rate constant (k1) of Zn was the highest as 0.1629 ~ 0.1991/ day, it was followed by Zn > Pb > Cd > Cu. Especially, Cu increased more than 2.0 times with the steel slag added, so it was very effective. Total leaching amount of heavy metal was the most TCLP test due to differences in the leaching conditions. Added with the slag, TCLP, Column and Exchangeable form (F1) more decreased. Phosphorus (P) leaching, stabilized by phosphate only, increased than the contaminated soil. But Leaching of P decreased considerably when it was processed in combination with slag. In particular Ca(H2PO4)2·H2O of phosphates showed to be the least leaching, it was expected made of metal-phosphate immobilized.
        38.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to evaluate the immobilization of heavy metals (Cu, Pb, Zn and Cd) in an abandoned mine soil by applying both soluble phosphates and steel slag as stabilizers. The application rate of stabilizers to soils was determinated based on PO4/Pb molar ratio of 2.0 for phosphates and on weight/weight ratio of 2, 5, 10% for steel slag, respectively. Immobilization efficiency of heavy metals in the contaminated soils was evaluated by toxicity characteristics leaching procedure (TCLP). After adding both phosphate and slag, the immobilization efficiencies of Cu, Zn and Cd increased significantly (about 14% - 40%) compared to those of treatment with soluble phosphate alone. The increae in immobilization efficiencies of Cu was the greatest. Whereas, immobilization efficiency of Pb was not significantly different from those with soluble phosphate alone. Among the tested three phosphates (Na2HPO4 ·12H2O, Ca(H2PO4)2 ·H2O, (NH4)2HPO4), the immobilization efficiencies with Na2HPO4 ·12H2O increased more than those of other phosphates. Results of sequential extraction analysis indicated that fraction of reducible form (F3) and residual form (F5) increased, while mobile forms (F1, and F2) decreased after immobilization treatment with both stabilizers resulting in decrease in leachability of heavy meyals in the treated soils. Residual fraction of Cu after treatnment was the highest as 68.5%, it was followed by Cu > Pb > Zn > Cd.
        39.
        2012.11 KCI 등재 서비스 종료(열람 제한)
        한중콘크리트 공사에 적용을 검토할 수 있는 초속경 콘크리트는 초기 급속한 발열반응을 통해 동해를 입기 전에 소요의 강도를 확보할 수 있을 것이며, 열 보상을 통해 시공환경이 유지될 경우 강도발현에 필요한 시간을 단축할 수 있는 장점이 있다. 일반 콘크리트는 영하의 기온에서 타설할 경우 양호한 경화를 얻을 수 없으며, 저온에서 동해를 방지하고 경화성을 확보하기 위하여 내한방동제를 첨가하여 사용하고 있다. 그러나, 내한방동제의 대부분은 염화물을 주성분으로 하고 이를 다량으로 사용할 경우, 콘크리트의 동결을 방지하고 시멘트의 수화반응을 촉진시켜 응결시간을 단축하고 초기강도 증진을 유도하는 효과가 있는 반면, 장기재령에서 강도발현이 문제가 되고, 경제성이 떨어진다는 단점이 있다. 최근 연구되고 있는 마그네시아 인산염 복합체는 초속경성이 있고 저온에서도 수화반응이 가능한 것으로 보고되고 있어 새로운 한중공사 및 극한지용 건설재료로 사용할 수 있을 것으로 판단된다. 따라서, 본 연구에서는 한중공사 및 극한지에서 사용이 가능한 건설재료의 개발을 위한 사전 연구의 일환으로서, 마그네시아 인산염 복합체를 활용한 모르타르에 대해 온도의 영향을 고려한 재료 물성 평가를 실시하고 적정 배합을 제안하고자 한다.
        40.
        2012.10 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to evaluate the immobilization efficiency and sequential extraction of soluble phosphates (Na2HPO4 ·12H2O, Ca(H2PO4)2 ·H2O, (NH4)2HPO4) for the stabilization of heavy metals (Cu, Pb, Zn and Cd) in abandoned mine soil. The application rate of stabilizers to soils was determinated PO4/Pbtotal molar ratio of 0.5, 1.0, 2.0, 4.0. The immobilization efficiency was evaluate of TCLP (EPA method 1311) used in a landfill for heavy metals. After processing stabilization, the immobilization efficiency of Pb is more than 95% at molar ratio of 2.0 regardless kind of phosphate. For Cu Zn and Cd, on the other hand, the efficiency has the range of from 30% to 50%, even though molar ratio increase up to 4.0. It is relatively low in comparison with Pb. Leachability of heavy metals was reduced with increasing amounts of added phosphate. Phosphates, Na2HPO4 ·12H2O was more immobilization than Ca(H2PO4)2 ·H2O, (NH4)2HPO4. After sequential extraction, form of heavy metals in soil tends to increase strongly bond like forms of organic matter-bound(F4) and residual (F5). Especially the stable residual form increases in all metals. The growth rate of residual fraction was a little different heavy metals. The growth rate of Zn is greatest increased from 17% to 22% than other metals, it was followed by Zn > Cd > Pb > Cu. Phosphates, Ca(H2PO4)2 ·H2O was the greatest increased for residual fraction.
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