• 대한화학회지
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• 제55권3호
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate는 마이크로파 조사조건에서 용매 없이 페놀과 아세토아세트산 에틸의 Pechmann 축합반응에 의하여 쿠마린을 합성하는 효과적인 촉매로 밝혀졌다. 이 방법은 쿠마린 합성에 있어서 소량의 촉매를 필요로 하며 수율이 높고, 반응이 깨끗할 뿐만 아니라 반응 시간이 짧은 장점들을 가지고 있다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.325-328
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• 2002

Sucrose 의 경우 저농도에서는 후반부로 갈수록 세포생장 속도는 현저히 감소하는데 비해 hGM-CSF 생산은 후반부에 급격히 증가함을 확인하였다. 고농도 sucrose를 사용하는 경우에는 lag phase가 길어지는 동안에 hGM-CSF의 생산이 증가하였다. 따라서 배양 초기에는 고농도 sucrose가, 배양 후반에는 저농도 sucrose로 존재하는 경우에 hGM-CSF를 많이 얻을 수 있었다. Nitrogen source의 농도는 60.52 mM과 121.04 mM일 때가 세포의 생장이나 hGM-CSF의 생산을 증가시켰으며, phosphate의 경우에는 4.96 mM 일 때가 대조구인 2.48 mM 일 때보다 hGM-CSF의 생산을 3 배 증가시켰다.

• 한국균학회지
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• 제23권1호통권72호
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• pp.53-60
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• 1995

Flammulina velutipes(팽나무버섯)의 영양요구성에 대한 연구로써 각종 탄소원 및 질소원을 처리한 결과 mannitol과 glutamic acid 그리고 ammonium nitrate가 최대 균사체 생장을 보였으며, 최적 C : N ratio 로써 20 : 1이 선정되었다. Phosphate source로는 potassium dihydrogen phosphate가 좋은 결과를 나타내었으며, magnesium sulphate와 thiamin HCl이 균사체 생장을 촉진하였다. 이상의 결과로 최적 화학합성배지의 조성은 1.5% mannitol, 0.082% $NH_4NO_3$, 0.312% glutamic acid, 0.25% $KH_2PO_4$, 0.06% $MgSO_4{\cdot}7H_2O$ 그리고 $0.3\;{\mu}g/l$ thiamin HCl로 나타났다. 이와 같은 배지의 조성은 균사체 생장 뿐만 아니라 자실체 생장에도 효과가 있는 것으로 나타났다.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.115-120
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• 1997

We have developed new algorithms for solution of the three-dimensional, time-dependent Navier-Stokes equations that utilize massively parallel supercomputing implemented on the Connection Machine 5. Here, we apply these techniques to analyze he fluid flows that occur during the growth of the tow nonlinear optical crystals-potassium dihydrogen phosphate (KDP), which is producted in a novel rapid growth system under development by the Lawrence Livermore National Laboratory Laser Division, and Potassium titanyl phosphate(KTP), which is grown from a high-temperature aqueous solution.

• 분석과학
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• 제34권5호
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• pp.212-224
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• 2021

The intent of the present work was to develop a simple, sensitive, accurate, precise, rapid and economical UV- spectrophotometric and reverse phase high pressure liquid chromatographic method for the simultaneous estimation of Spironolactone and Furosemide in bulk and combined tablet dosage forms. UV-Spectrophotometry was carried out by simultaneous equation method using 0.02 M potassium dihydrogen phosphate buffer pH 3.5: Acetonitrile (50:50) v/v as a solvent. The linearity range was 2-14 ㎍ mL^-1 for Spironolactone and Furosemide with a correlation coefficient > 0.99. The chromatographic separation was achieved on 250 mm × 4.6 mm, hypersil BDS C18 column with particle size 5 ㎛, by using an isocratic mixture of 0.02 M potassium dihydrogen phosphate buffer pH 3.5: Acetonitrile: tert butyl methyl ether (49:50:1) v/v/v as a solvent at a flow rate of 1 mL min^-1 and UV detection was carried out at 254 nm. The retention time were observed to be 3.666 and 6.661 minutes for Furosemide and Spironolactone respectively. The two developed methods were validated according to the ICH guidelines for accuracy, precision, linearity, LOD, LOQ and were found to be within the limits. It can be concluded that these two methods could be successfully used for the simultaneous estimation of Spironolactone and Furosemide in bulk and combined tablet dosage forms.

• 약학회지
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• 제21권1호
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• pp.1-16
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• 1977

The effect of condensates of phosphates on the preservative activity of the food additives, using eight micro-organisms, has been studied by the agar dilution method. It was found that condensates of phosphates increased the food preserving action of almost all of preservatives and they acted as a synergist for the action of almost all of preservatives. Disodium dihydrogen prrophosphate acted as the strongest synergist in the experiment. But sodium tripolyphosphate anhydrous, sodium poly-phosphate, sodium tripolyphosphate and sodium hexametaphosphate acted as a inhibitor for action of some preservatives on some orgnisms. The preservatives were sodium dehydroacetate (DHA), potassium sorbate and NaNO$_{2}$ etc. The action of sodium meta-phosphate on the preservatives produced a mean difference by their origins. It was supposed that such a difference was produced by the difference of amount of impurities that were contained in sodium metaphosphate, It was also supposed that the does of the preservatives could be reduced by addition of condensates of phosphates, acting as a synergist for the action of almost all of the preservatives.

• 한국구조물진단유지관리공학회 논문집
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• 제23권3호
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• pp.103-110
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• 2019

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.

• 대한전자공학회논문지
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• 제7권2호
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• pp.1-12
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• 1970

본 논문에서는 선형전기광효과(Pockel 효과)를 이용하여 X대역 마이크로파(9375 MHz)를 광변조하는데 관하여 이론적인 해석과 실험적인 연구를 했다. 전기광 결정체 KDP를 공진형 변조기로 설계하여 z축으로 광선과 평행하게 마이크로파 전계를 인가하여 변조했다. 변조파 출력을 가변단락판의 위치변화에 따라 관찰했으며 /2에서 변조가 잘 개폐되는 것을 알았다. 또한 출력변조의 세기를 인가 전계의 세기를 변화시켜 측정하여 이론곡선과 비교해서 약 5%의 오차를 얻었다. 결과적으로 아직 해결되어야 할 문제는 많이 있지만 비교적 만족스러운 광변조기를 얻었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.153-153
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• 2022

There is a growing need to develop ion sensors for agriculture. As a result, several technologies have been developed, such as colorimetry, spectrophotometry, and ion-selective electrode (ISE). Among them, ISE has some advantages compared to others. First, it does not require pre-treatment processes and expensive equipment. Second, it is possible for the portable detection system by introducing small-sized electrodes. Finally, real-time and multiple detections of several ions are pursued. It is well-known that N, P, and K nutrients are critical for crop growth. With the development of agriculture techniques, the importance of soil nutrient analysis has attracted much attention for cost-effective and eco-friendly agriculture. Among several issues, minimizing the use of fertilizers is significant through quantitative analysis of soil nutrients. As a result, it is highly important to analyze certain nutrients, such as N (ammonium ion, nitrate ion, nitrite ion), P (dihydrogen phosphate ion, monohydrogen phosphate ion), and K (potassium ion). Therefore, developing sensors for accurate analysis of soil nutrients is highly desired. n this study, several ISEs have been fabricated to detect N, P, and K. Their performance has been intensively studied, such as sensitivity, selectivity coefficient, and concentration range, and compared with commercialized ISEs. In addition, preliminary tests on the in-situ N, P, and K monitoring have been conducted inside the soil.

• 한국미생물·생명공학회지
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• 제45권4호
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• pp.330-342
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• 2017

Statistical design of experiments was employed to optimize the media composition for the production of laccase from Bacillus sp. PK4. In order to find the key ingredients for the best yield of enzyme production from the selected eleven variables viz yeast extract, glucose, zinc sulphate, copper sulphate, potassium chloride, magnesium sulphate, calcium chloride, ferrous sulphate, sodium chloride, potassium dihydrogen phosphate ($KH_2PO_4$) and dipotassium hydrogen phosphate ($K_2HPO_4$), Plackett-Burman design was applied. The $MgSO_4$, $FeSO_4$, and $CuSO_4$ showed positive estimate, and their concentration optimized further. The steepest ascent method and Box-Behnken method revealed that 1.5 mM $MgSO_4$, 0.33 g/l $FeSO_4$ and 1.41 mM $CuSO_4$ were optimal for the laccase production by Bacillus sp. PK4. This optimization strategy leads to enhancement of laccase production from 2.13 U/ml to 40.79 U/ml. Agro-wastes residues replace the carbon source glucose in the optimized media namely sugarcane bagasse, wheat bran, rice husk, and groundnut shell, among these groundnut shells (117 U/ml) was found to enhance the laccase production significantly. The laccase produced by Bacillus sp. PK4 was found to have the potential to degrade persistent organic pollutant benzo[a]pyrene.