• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate was found to be an efficient catalyst for the Pechmann condensation of phenols with ethyl acetoacetate, leading to the formation of coumarins under microwave-irradiation and solvent-free condition. This procedure offers several advantages, including the low loading of catalysts, high yields, clean reactions, short reaction time for the synthesis of coumarins.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.325-328
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• 2002

Production of human granulocyte-macrophage colony stimulating factor (hGM-CSF) by Nicotiana tabacum cell suspension culture was studied in Murashige and Skoog (MS) medium with sucrose as a carbon source, ammonium nitrate and potassium nitrate as nitrogen sources, potassium dihydrogen phosphate and sodium dihydrogen phosphate hydrate as phosphate sources, respectively. Optimum concentrations for carbon, nitrogen, phosphate was determined to enhance the production of hGM-CSF. Cell growth was better at high initial sucrose concentration (60 g/L), high initial nitrogen concentration (121.04 mM). Maximum cell density (18.28 g/L) was obtained at 60 g/L of sucrose after 14 days. Cell growth was not so good at low initial sucrose concentration 00 g/L), but the highest hGM-CSF production was obtained at the latter half of exponential phase. hGM-CSF production increased about 3 fold at initial phosphate concentration of 4.96 nM

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.53-60
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• 1995

Nutritional requirements for the growth of Flammulina velutipes were studied. Mannitol, glutamic acid and ammonium nitrate were chosen for the maximum mycelial growth when various carbon and nitrogen sources tested. Optimum C : N ratio for the mycelial growth was 20 : 1. Potassium dihydrogen phosphate was selected among the phosphate sources. Magnesium sulphate and thiamine HCl stimulate mycelial growth. Final compositions of optimized chemically defined medium were 1.5% mannitol, 0.082% $NH_4NO_3$, 0.312% glutamic acid, 0.25% $KH_2PO_4$, 0.06% $MgSO_4{\cdot}7H_2O\;and\;0.3\;{\mu}g/l$ thiamin HCl. This medium not only support mycelial growth but also induce fruit body formation.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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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.

• Analytical Science and Technology
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• v.34 no.5
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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.

• YAKHAK HOEJI
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• v.21 no.1
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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.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.103-110
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• 2019

Damage to the pavement system due to various causes will be required rapid repair work for reopening the vehicle traffic. The magnesium oxide phosphate composite(MPC) has a short curing time and is capable of early compressive strength development, is suitable for rapid repair materials. The aim of this study was to evaluate the hardening and compressive strength characteristics of MPC according to the water-binder (W / B) ratio and magnesium-phosphate(M / P) ratio in order to develop repair materials consisted with light burned magnesia and potassium dihydrogen phosphate. In order to ensure the workability in the field application, the difference of mechanical properties according to standard sand and ordinary sand and performance of retards were evaluated. The mix proportion with W/B ratio was about 35% and the M/P ratio was about 1.0 ~ 1.2 has a superior perfomance with strength and hardening condition. Especially, the strength of composite at only 1 day curing with W/B ratio of 0.35 and the M/P ratio of 1.2 was shown the higher than 25.0 MPa. Boric acid as a retarder was found to be suitable for ensuring the working time, and the purity of magnesium oxide was about 90 ~ 95%, which is effective for ensuring curing time and strength.

• Journal of the Korean Institute of Telematics and Electronics
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• v.7 no.2
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• pp.1-12
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• 1970

In this paper, theoretical and experimental study about the light modulation at X-band(9375MHz) micro wave, using the linear electro-optic effect, has been described. The electro-optic crystal, KDP (potassium dihydrogen phosphate)is used for modulator crystals which is composed resonated modulator. Output performances of modulated wave through movable short positions are presented. It was critically respond from 2. And the output modulated intensity was compared with theoretical curve. Consequently, in spite of many problems remain yet, most promissing and more sucessful modulator configurations are compleely given.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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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.

• Microbiology and Biotechnology Letters
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• v.45 no.4
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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.