• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.45-45
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• 1993

괄루근으로부터 분리된 다당류에 대하여 continuous gel electrophoresis, SDS-Polyacrylamide gel eletrophoresis, ion exchange column chromatography, Hydroxyapatite column chromatography 및 Gel filtration등의 방법을 이용하여 다음과 같은 결과를 얻었다. 1) 황산암모늄 분별침전법에 의한 렉틴의 정제도는 초추출물의 4.85배이며 DEAE Sephadex A-50 column chromatography법에 의한 정제도는 24.17배로 나타났고, 마지막 정제단계인 Sephacryl S-200 gel filtration에 의한 정제도는 47.34배로 나타났다. 2) 정제된 렉틴의 분자량은 60,000da1ton으로 나타났다. 3) 사람의 혈액형에 따른 응집효과는 90-100％로 특이성은 없었다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.136-136
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• 1993

immunotoxin으로 쓰일 수 있는 리보솜 불활성화 단백질 (RIP, ribosome-inactivating protein)을 보리 씨앗에서 분리하였다 이 단백질은 분자량이 약 30,000 kDa 정도되고, pl가 9.0 보다 높다. 이러한 성질을 이용하여 Na-phosphate 완충용액으로 추출하고, 황산암모늄 60-80％ 포화로 분획화하였다. 다음 CM-cellulose를 이용한 이온 교환 크로마토그래피, Sephacryl S-200 HR 컬럼을 이용한 gel filtration을 하여 순수히 분리하였고, 이를 전기영동하여 확인하였다.

• 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.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.80-87
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• 1985

Radiation damage in a single crystal of ammonium sulfate caused by ${\gamma}$-irradiation at room temperature has given rise to several paramagnetic centers. Electron spin resonance (ESR) spectra of crystal are obtained with the X-band EPR spectrometer at room temperature. An intense and isotropic peak of Gaussian shape at g = 2.0036 is assigned to $SO_3^-$, which shows power saturation effects. Angular dependence of spectra is studied for the rotations about three mutually perpendicular axes a, b and c. The g-values are obtained from the relative distances between isotropic peak of $SO_3^-$ and anisotropic peak of the species. Principal $g^-$values and direction cosines were calculated by diagonalizing the 3${\times}$3 matrix whose elements are the $g^-$values for each species. From the analysis of characteristic principal $g^-$values and direction cosines for ammonium sulfate single crystal, anisotropic peaks corresponding to $SO_4^-,\;SO_2^-$ and defect structure corresponding to electron excess type are identified.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.289-295
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• 2017

The International Maritime Organization (IMO) in accordance with the regulations with respect to the combustion gases, such as NOx, SOx generated by the marine engine. The combustion gases must be equipped with a device to reduce emissions from all ships passing through the Baltic SECAs. In Korea, the International Maritime Organization (IMO) and the development of a device for NOx, SOx reduction. Scrubber is used in the ammonia water and the Urea solution in the waste water. The waste water containing ammonium nitrate and ammonium sulfate, react of the NOx and SOx gas. In this study, the recovery of by-product, which contains the waste water was used as an organic solvent extraction method of salting out. Ammonium nitrate and ammonium sulfate, the recovery process. A qualitative analysis of the collected by-product FT-IR analysis. Through the elemental analysis and SEM-EDS, characteristic evaluation was performed with an impurity.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.210-216
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• 2017

Recovery of low level nitric acid and sulfuric acid ions, which were contained in wastewater of a wet scrubber for de-NOx and de-SOx from ship engines, was attempted as fertilizing materials. This study utilized a selective extraction method using four organic solvents to precipitate the solid salts of ammonium nitrate and ammonium sulfate. The IR analysis showed almost same composition of the extracted ammonium salts with a commercial product, and recovery rate of nitrogen and sulfuric ions was 89% and 80% respectively. It was found that the selectivity and solubility consequently could be the crucial factors to recover the low level ions from the waste scrubbing water.

• 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 the Korean Ceramic Society
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• v.40 no.9
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• pp.897-901
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• 2003

The sulfating reaction of coal fly ash with ammonium sulfate and the microwave extraction of aluminum ions from the resultant materials using sulfuric acid have been investigated. The (NH$_4$)$_3$Al(SO$_4$)$_3$ formed by the reaction of coal fly ash and ammonium sulfate decomposed to NH$_4$Al(SO$_4$)$_2$ at $\geq$ 350$^{\circ}C$. The maximum efficiency of aluminum ions extracted from the sulfating reaction product (400$^{\circ}C$, 120 min) by microwave heating (90$^{\circ}C$, 240 min) using 1 M H$_2$SO$_4$ was 84％ (based on Al content in coal fly ash) but 77％ by conventional heating at same condition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7433-7438
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• 2015

Deactivation characteristics of $V_2O_5/TiO_2$ catalysts were studied for selective catalytic reduction(SCR) of NOx with ammonia in the presence of $SO_2$. Performance of catalyst was investigated for $deNO_x$ activity while changing temperature, $SO_2$ concentration. The activity of catalyst was decreased with the increase of $SO_2$ concentration and reaction time. Also, degree of activity drop was largely decreased with the increase of reaction temperature in the range of $250{\sim}300^{\circ}C$. Physicochemical properties of deactivated catalysts were characterized by BET, XRD, SEM, TPD analysis. According to the analysis results, deactivation phenomena occur due to the relatively high formation of ammonium sulfate salts, which created by unreacted ammonia and water in the presence of $SO_2$. It was revealed that ammonium sulfate cause the pore plogging of support and deposition of active matter.

• Resources Recycling
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• v.3 no.3
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• pp.21-26
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• 1994

In present study an attempt has been made to extract the high purity $Al_2O_3$from domestic aluminous shale. The processes of the salt roasting with ammonium sulfate, extraction with sulfuric acid and calcination were adopted. In the extraction of alumina, the effects of the sulfuric acid concentration, the reaction time and the temperature has been investigated. The reaction products were analyzed by X-ray diffraction, DTA-TG, chemical analysis and SEM. The results are summerized as follows: 1)The pretreatment conditions were 0.6M-$(NH_4)_2SO_4$and $650^{\circ}C$ in sintering temperature. 2) The optimum extraction conditions were $10%-H_2SO_4$ and 240 minutes in acid treating time. 3)Physical properties of sintering materials were confirmed as $\alpha-Al_2O_3$ by X-ray diffraction method and the purity of $\alpha-Al_2O_3$ was 99.23%.