• Journal of the Korean Wood Science and Technology
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• v.11 no.3
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• pp.23-30
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• 1983

This experiment was carried out for diminishing the material loss and the damage of human life due to the fire disaster by treating plywood with fire retardant chemical solution. At this study, we observed and measured chemical retention, burning point, maximum flame length, flame exausted time, carbonized area, and weight loss of plywood treated by each solution of ammonium sulphate [$(NH_4)_2SO_4$] and monoammonium phosphate [$NH_4H_2PO_4$]. Obtained results at the study may be summarized as follows: 1. In case of monoammonium phosphate-treated plywood, every tested item of fire retardancy was shown more excellent at the 25% chemical concentration and shown also at 9 hours treatment except maximum flame length compared with ammonium sulphate-treated plywood. 2. However in case of ammonium sulphate-treated plywood, 6 hours treatment of fire retardancy was better than 9 hours treating time. 3. Monoammonium phosphate was generally better than ammonium sulphate in every tested item.

• 월간산업보건
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• s.291
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• pp.12-16
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• 2012

과황산암모늄 (ammonium persulfate), 과황산칼륨(potassium persulfate), 과황산나트륨(sodium persulfate)에 대한 작업 노출기준은 perfulfate ($S_2O_8$) 형태로서 0.1 $mg/m^3$(TLV-TWA)으로 권고하였다. 이 기준치는 피부 자극 및 피부염을 포함한 피부 또는 기관지계 관련 질환 발생을 최소화하기 위해 설정되었다. 몇몇 연구 자료에 의하면 이 물질들에 노출되면 폐 자극 증세도 나타난다고 보고되고 있다. 또한 이 TLV는 전신독성 측면보다는 자극 영향 측면에 근거를 두어 제안하였다. "감작제(SEN)", 발암성, TLV-STEL에 대한 설정은 유용한 자료의 부족으로 아직 권고하지 않고 있다.

• Korean Journal of Food Science and Technology
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• v.5 no.2
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• pp.78-83
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• 1973

The naringin hydrolyzing enzyme has been purified from the culture filtrate of the mold Aspergillus S-1 which selected to remove the bitter test of the orange or citrus fruits industrily. In a view of purity naringinase was more effectively purified in order of molecular sieving on Sephadeex G-200, starach gel electrophoresis, chromatography or a DEAE-Cellulose column and fractional precipitation by ammonium sulfate. The purified enzyme is homogeneous in paper electrophoresis from a culture filtrate by treatment fractional precipitation with ammonium sulfate, DEAE-Cellulose treatment and Sephadex-200 column chromatography and it hydrolyse only naringin to purunin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1009-1017
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• 2008

For the effective use of exopeptidase from squid viscera as food processing aids, the viscera of Argentina shortfin squid (Illex argentinus) were fractionated by various methods such as acetone treatment, ammonium sulfate treatment, anion exchange chromatography, and gel filtration. The positive exopeptidase fractions were obtained from the fraction II treated by cold acetone ($30{\sim}40%$, w/w), the fraction V by ammonium sulfate ($60{\sim}70%$ saturation), the fraction II (0.2 M NaCl) by anion exchange chromatography, and the fraction I ($30{\sim}50\;kDa$) by gel filtration. The specific activities of positive fractions from viscera of I llex argentinus against substrates were higher to LeuPNA than to ArgPNA. Total activity and recovery against LeuPNA of positive fraction by gel filtration were 1,867 U and 30.69%, respectively, which were the highest among those of positive fraction. The results suggested that the gel filtration chromatography method was the most efficient method for the fractionation of exopeptidase from viscera of Illex argentinus.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.19-25
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• 2017

This study was conducted to investigate the effects of nitrogen fertilization on physiological characteristics and growth of Populus sibirica seedlings in a semi-arid area, Mongolia. 2-year-old P. sibirica seedlings were planted in May, 2015 with applications of urea 5 g (N1), 15 g (N2), 30 g (N3) and ammonium sulfate 33 g (NS; same nitrogen amount with N2) to each seedling. Chlorophyll contents were significantly different among treatments in August, but not in June and July. The lower chlorophyll contents in August than those in June and July might be related to leaf senescence. In June and July, net photosynthetic rate was higher in NS and N2 than in the control. Unlike the tendency of photosynthesis, transpiration rate was highest in N2, but lower in NS than in any other nitrogen treatments. Relative growth rate of root collar diameter was significantly higher only in NS than in the control and it of height did not differ among treatments. Leaf area in nitrogen treatments was not significantly different from that in the control. Ammonium sulfate seemed to be more suitable fertilizer than urea for the early growth of P. sibirica seedlings in the study site. However, as the effects of urea and ammonium sulfate on soils and seedlings were different, further studies would be necessary to determine the optimal amount of ammonium sulfate.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.190-198
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• 1983

To examine the possibility of enhancing activity of foliar applied herbicides by spray methods and additives, field experiments were conducted to evaluate the effects of surfactant, spray volume, and additions of ammonium sulfate or potassium chloride to glyphosate on toxicity to Digitaria sanguinalis or Artemisia princeps. Glyphosate toxicity increased as spray volume was decreased from 120 1/10a to 40 and 80 1/10a. Additions of surfactant in the spray solution increased toxicity of glyphosate to D. sanguinalis and usually more pronounced effect was obtained at glyphosate 30.5g a.i./10a. Additions of 1 and 5% (w/v) ammonium sulfate to glyphosate increased toxicity to A. princeps at glyphosate 30.5 and 61.5g a.i./10a. 10% ammonium slufate, however, had no effect or were antagonistic. Additions of potassium chloride at 1,2 and 3% (w/v) were also very effective to increase herbicidal activity to A. princeps at glyphosate at 30.5 and 61.0g a.i/10a. These results suggest that the practices for enhancement of herbicidal activity by improvement of spray method and additions of ammonium sulfate or potassium chloride to glyphosate can be employed to use lower herbicide levels while giving the same degree of weed control in orchards and non-crop lands.

• Resources Recycling
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• v.31 no.4
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• pp.40-48
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• 2022

In waste lithium iron phosphate (LFP) batteries, the cathode material contains approximately 4% lithium. Recycling the constituent elements of batteries is important for resource circulation and for mitigating the environmental pollution. Li contained in the waste LFP cathode powder was selectively leached using persulfate-based oxidizing agents, such as sodium persulfate, potassium persulfate, and ammonium persulfate. Leaching efficiency and waste LFP powder properties were compared and analyzed. Pulp density was used as a variable during leaching, which was performed for 3 h under each condition. The leaching efficiency was calculated using the inductively coupled plasma (ICP) analysis of the leachate. All types of persulfate-based oxidizing agents used in this study showed a Li leaching efficiency over 92%. In particular, when leaching was performed using (NH₄)₂S₂O₈, the highest Li leaching percentage of 93.3% was observed, under the conditions of 50 g/L pulp density and an oxidizing agent concentration of 1.1 molar ratio.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.567-572
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• 2010

5,10-Methenyltetrahydrofolate synthetase from chicken liver was purified through 30-70% ammonium sulfate fractionation, Q Sepharose Fast Flow anion exchange and Source 15Phe hydrophobic interaction chromatography. Specific activities of cell extract, ammonium sulfate, Q Sepharose Fast Flow and Source 15Phe were 0.0085, 0.031, 0.80 and 1.27 U/mg, respectively. Purification fold activities of cell extract, ammonium sulfate, Q Sepharose Fast Flow and Source 15Phe were 1, 3.7, 94.1 and 149.4, respectively. HPLC gel permeation chromatography and SDS-polyacrylamide electrophoresis experiments indicated that the enzyme is a monomeric protein with a molecular weight of 22.8 kDa. Km for 5-methyl THF and Mg-ATP were $7.1\;{\mu}M$ and $63\;{\mu}M$, respectively. Optimum temperature and pH were $30^{\circ}C$ and 6.0, respectively. The data for metal ion specificity and stoichiometry showed that the maximum activity was obtained with a 1:l. ratio of $Mg^{2+}$. The ATP and Km values increased in the order of MgATP, MgCTP, MgUTP and MgGTP, and the maximum activities also decreased in the same order, indicating MgATP as the most efficient substrate. The enzyme was chemically modified only by tetranitrometane and 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide, indicating that tyrosine and carboxylate are present in the active site.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.05a
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• pp.51-52
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• 2000

전기아연도금강판은 표면이 미려하고 희생방식력이 뛰어나기 때문에 주로 자동차와 가전, 건자재 등에 많이 사용된다. 현재 냉연 표면처리 제품들은 연속도금공정에 의해 생산되고 있으며 고전류밀도에 의한 고속생산과 도늠액 제조와 조성이 비교적 단순해야 하는 여러 가지 이유로 염산욕과 황산욕을 가장 많이 사용하고 있다. 최근에 신설된 당사의 전기도금공정은 수직형으로 황산욕에서 불용성 양극을 채용하여 아연을 전기도금하고 있다. 일반적으로 황산욕은 염산욕 대비 전기 전도성이 나빠 과전압이 크게 걸리므로 불용성 양극을 사용하여 극간 거리를 최소화할 필요가 있다. 그러나 $Ir0_2$가 코팅된 불용성 양극은 가격이 비싸기 때문에 극간 거리를 너무 짧게 하면 깡대에 의해 손상을 받을 수가 있어 극간 거리를 줄이는데 한제가 있다. 따리서 용액의 전도도들 증가시켜 과전합을 줄이기 위해서는 타사에서 현재 사용하고 있는 황산나트륨, 황산칼륨, 황산암모늄 등에 대한 검토가 필요하다. 전기전도 보조제들은 용액의 전기전도도 뿐만 아니라 도금층의 외관 및 미세구조에도 많은 영향을 주는 것으로 알려져 있다. 따라서 본 연구에서는 황산나트륨, 황산암모늄의 농도를 변화시켜 표면외관, 한계전류밀도, 미세구조, 우선배향성 등을 조사하여 최적의 물성을 갖는 아연 도금층을 얻기 위한 조건을 도출하고자 하였다. 전기아연도금용 소재로는 두께 0.8mm이고 크기가 $100{\times}120mm$인 중저탄소강 (0.02% C)을 사용하였으며 전처리 과정으로 탈지와 산세를 행하고 현장 도금액을 사용하여 다음과 같은 조건 하에서 아연도금을 행하였고 극간전합을 측정하였다. 도금 후 표면의 미세구조는 SEM을 사용하여 관찰하였으며 표면외관 특성을 분석하기 위해 광택도계(Tri- Microgloss-60-85)를 이용하여 입사각 $60^{\circ}$ 에서 광택도를 측정하였고, 색차계(Color Quest II Hunter Lab.)를 사용하여 백색도를 각각 측정하였다. 또한 X선 회절기를 이용하여 도금층의 우선 배향성을 분석하였다.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.505-510
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• 1998

This study has been carried out to investigate Electrostatic Precipitator's(ESP) performance enhancement and removal efficiency of fine particle according to (NH4)2SO4injection rate. The following conclusions are derived from the these test results : 1) For plant condition cases, according to the variation of concentration agent [(NH4)2SO4]-10ppm, when inlet dust loading was 2g/m2. And when Inlet dust loading was 3g/m", that was increased to 98 19% 99.16% 99.23%, 99.58%, 2) It Is seen from thins experiments that the increasing 30ppm concentration of (NH4)2SO4 increase the collection efficiency and fine particle omission control.