• 한국결정성장학회지
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• 제24권2호
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• pp.84-87
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• 2014

Separation/recovery of valuable metals such as zinc, nickel or tin from copper alloy dross has recently attracted from the viewpoints of environmental protection and resource recycling. In this study, preliminary investigation on separation of tin (Sn) from copper alloy dross using selective dissolution method was performed. The tin in the copper alloy dross did not dissolve in an aqueous nitric acid solution which could allow the concentration/separation of tin from the copper alloy dross. Precipitation of tin as $H_2SnO_3$ (meta stannic acid)occurred in the solution and transformed to tin dioxide ($SnO_2$) after drying process. The dried sample was heat-treated at low temperature and its crystal structure, surface morphology and chemical composition were investigated.

• 약학회지
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• 제47권5호
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• pp.339-344
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• 2003

Atenolol is a water soluble, ${\beta}_1$ selective adrenoceptor antagonist used in the treatment of angina and hypertension. It is primarily eliminated renally with minimal hepatic metabolism. The purpose of the present study was to evaluate the bioequivalence of Samchundang Atenolol (Samchundang Pharmaceutical Co., Korea.) to Tenolmin(Hyundai Pharmaceutical Ind. Co., Korea). The atenolol release from the two atenolol tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty four normal male volunteers, 22.83$\pm$1.99 years in age and 65.82$\pm$7.15 kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 50 mg of atenolol was orally administered, blood was taken at predetermined time intervals and the concentrations of atenolol in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two atenolol tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_{t}$ and $C_{max}$ and untransformed $T_{max}$. The results showed that the differences in $AUC_{t}$, $C_{max}$ and $T_{max}$ between two tablets based on the Tenolmin were 3.74％, 4.38％ and 17.77％, respectively. There were no sequence effects between two tablets in these parameters. The 90％ confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g., log(0.98)∼log(1.l1) and log(0.95)∼log(1.l5) for $AUC_{t}$ and $C_{max}$ respectively), indicating that Samchundang Atenolol tablet is bioequivalent to Tenolmin tablet.

• 대한가정학회지
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• 제32권4호
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• pp.85-95
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• 1994

Today the occurrence and world-wide transfusion of the AIDS has brought about new problems related to family relations. The AIDS is more threatening than any other disease because of the special processes of infection trough sex and intravenous injections high care cost and terminal death. The AIDS causes conflicts among family members economic destitution and family dissolution. In the U.S Marriage without noticing of the AIDS may lead to divorce like injuries abandonment and misfeasance during marriage. But the AIDS victims should not be rejected from the rights of parental decision divorce beneficiaries and visiting rights. More discussion is needed about such issues as the pregnancy rights rongful birth action and selective nontreatment by doctors. The AIDS may influence the every party involved and interdisplinary studies should be required to solve the problem including family science laws psychology sociology and medical research as well.

• 한국광물학회지
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• 제2권1호
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• pp.37-46
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• 1989

X-ray, optical and electron microscope studies exhibit that the amphiboles in anorthositic saprolite from kaolin deposits, located in Suryun-myeon, Seongju-gun, Kyungsangbuk-do, have altered under weathering conditions to smectite, mixed-layer mineral, vermiculite and goethite. In early supergene alteration stage when rock structure is still preserved, smectite occurs as initial weathering product of amphibole. Further weathering leads to the formation of mixed-layer mineral, vermiculite and goethite as indicated by XRD and SEM studies. Scanning electron microscopy studies of amphibole show that the dissolution of amphibole proceeds by selective etching at the surface along weaker zones producing distinct etch pattern, The calcic amphiboles according to electron microprobe analyses, show leaching of the most mobile elements (Mg, Ca and Fe) during alteration.

• Computers and Concrete
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• 제7권1호
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• pp.17-38
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• 2010

This research aimed to investigate the influence of high-volume mineral admixtures (MAs), i.e., fly ash and slag, on the hydration characteristics and microstructures of cement pastes. Degree of cement hydration was quantified by the loss-on-ignition technique and degree of pozzolanic reaction was determined by a selective dissolution method. The influence of MAs on the pore structure of paste was measured by mercury intrusion porosimetry. The results showed that the hydration properties of the blended pastes were a function of water to binder ratio, cement replacement level by MAs, and curing age. Pastes containing fly ash exhibited strongly reduced early strength, especially for mix with 45% fly ash. Moreover, at a similar cement replacement level, slag incorporated cement paste showed higher degrees of cement hydration and pozzolanic reaction than that of fly ash incorporated cement paste. Thus, the present study demonstrates that high substitution rates of slag for cement result in better effects on the short- and long-term hydration properties of cement pastes.

• Archives of Pharmacal Research
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• 제4권2호
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• pp.85-90
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• 1981

A quantitative GC-MS spectrometric assay was used for the determination of residual N, N-dimethylaniline as a contaminant in commercial penicillin derivatives from various sources. The assay utilizes selective ion focusing to monitor in a GC effluent the molecular ions of DMA generated by electron impact ionization. This method includes dissolution of the sample in alkaline solution, extraction of organic base with cyclohexane and injection into GC-MS with a 3% OV-17 column. Levels of 50 ppb of DMA were easily measured with a coeffecient of varation less than 5 % and recoveries from spiked samples exceeded 97 %. The results of the determinations of DMA in various commercial penicillins were relatively free of this contaminant.

• 부식과 방식
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• 제12권1호
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• pp.12-23
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• 2013

원자력 발전소 주요 부품에 사용되는 Alloy 600의 PWSCC 개시와 전파기구를 살펴보고 그 억제 기술을 소개하였다. ○ 균열은 경화된 표면 산화층이 깨질 경우, 입계부식, 공식(pitting), 열처리 또는 물속에 노출되었을 때 일어나는 선택부식(selective corrosion), MnS등 게재물의 용출등에 의해 시작된다. ○ 균열의 전파는 '느린 성장'과 '빠른 성장'으로 구별해 볼 수 있는데 빠른 균열성장은 균열 선단에서의 응력확대 계수(K_I)가 균열이 전파하는 임계값(K_Iscc)을 넘는 경우에 일어난다. ○ Slip Dissolution/Film Rupture Model, Enhanced surface mobility model, Hydrogen assisted creep rupture, Internal oxidation 등의 모델이 제시되어 있으며 Internal oxidation 모델이 여러 실험자료로 잘 뒷 받침되고 있다. ○ PWSCC 억제 방안으로는 부식환경과의 격리 및 보수용접이 대표적이며 부품의 교체를 통한 안전 확보의 방안도 있다. 수소량 조절을 통한 억제 방안도 제시되어 있다. ○ Alloy 600 PWSCC열화 관리 전략프로그램은 결함 발생 가능성이 높은 부위 선정, 우선 순위에 따른 계획적인 검사, 결함이 발견될 경우 완화조치를 취하거나 필요시 교체/보수를 실시하고 그 운영프로그램을 지속적으로 갱신관리하는 방안으로 유지되어야 한다.

• 콘크리트학회논문집
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• 제26권6호
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• pp.723-730
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• 2014

최근 고로슬래그 미분말의 사용량이 증가함에 따라 고로슬래그 미분말 혼입 시멘트의 수화반응 모델뿐만 아니라 압축강도, 수화생성물, 수화열 등 고로슬래그 미분말 혼입 시멘트 페이스트의 물성에 관한 연구가 활발히 진행되고 있다. 하지만 고로슬래그 미분말 혼입 시멘트 페이스트의 물성에 큰 영향을 끼치는 고로슬래그 미분말의 반응도에 대한 연구는 세계적으로도 부족하며 특히 국내에서는 전무한 실정이다. 따라서 본 연구는 선택적 추출법을 이용하여 시멘트 페이스트 내 고로슬래그 미분말의 반응도를 정량분석하고 물 바인더비, 치환율, 양생온도에 따라 압축강도, 화학결합수, $Ca(OH)_2$을 측정하여 비교 분석 하였다. 실험결과 시멘트 페이스트 내 고로슬래그 미분말의 반응도, 화학결합수, $Ca(OH)_2$은 치환율이 낮고 물 바인더비와 양생 온도가 높을수록 높게 나타났으며 특히 고로슬래그 미분말의 반응도는 최종적으로 약 0.3~0.4 값에 수렴하는 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제41권5호
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• pp.317-322
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• 2011

Sertraline HCl, (1S-cis)-4-(3, 4-dichloro-phenyl)-1, 2, 3, 4-tetrahydro-N-methyl-l-naphthalenamine hydrochloride, is a potent and selective serotonin reuptake inhibitor which is used in the treatment of depression and obsessivecompulsive disorders. The purpose of the present study was to evaluate the bioequivalence of two sertraline HCl tablets, Traline tablet (Myungin Pharm. Co. Ltd.) and Zoloft$^{(R)}$ tablet (Pfizer Inc.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The in vitro release of sertraline from the two sertraline HCl formulations was tested using KP VIII Apparatus II method with various dissolution media. Twenty four healthy Korean male volunteers, $23.50{\pm}1.74$ years in age and $64.09{\pm}7.10\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ crossover study was employed. After a single tablet containing 50 mg as sertraline HCl was orally administered, blood samples were taken at predetermined time intervals and the concentrations of sertraline in serum were determined using an online columnswitching HPLC method with UV/Vis detection. The dissolution profiles of two formulations were similar in all tested dissolution media. The pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated, and computer programs (Equiv Test and K-BE Test) were utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and un-transformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, Zoloft$^{(R)}$ tablet, were 0.04, 3.26 and -1.29% for $AUC_t$, $C_{max}$, and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log0.8 to log1.25. Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Traline tablet was bioequivalent to Zoloft$^{(R)}$ tablet.

• 약학회지
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• 제52권3호
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• pp.188-194
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• 2008

Fexofenadine, ($\pm$)-4-1-hydroxy-4-{4-(hydroxydiphenylmethyl)-1-piperidinyl}-butyl-a,a-dimethyl benzeneacetic acid, is a selective histamine $H_1$ receptor antagonist, and is clinically effective in the treatment of seasonal allergic rhinitis and chronic idiopathic urticaria as a first-line therapeutic agent. The purpose of the present study was to evaluate the bioequivalence of two fexofenadine hydrochloride tablets, $Allegra^{(R)}$ (Handok Pharmaceuticals Co., Ltd.) and Alecort (Samchundang Pharmaceutical Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of fexofenadine from the two fexofenadine hydrochloride formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media. Twenty six healthy male subjects, 25.62$\pm$3.35 years in age and 70.05$\pm$11.71 kg in body weight, were divided into two groups and a randomized 2$\times$2 cross-over study was employed. After a single tablet containing 120 mg as fexofenadine hydrochloride was orally administered, blood samples were taken at predetermined time intervals and the concentrations of fexofenadine in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar in all tested dissolution media. The harmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated, and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Allegra^{(R)}$, were -1.37, 5.22 and 16.50% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 (e.g., log 0.83$\sim$log 1.08 and log 0.81$\sim$log 1.03 for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Alecort tablet was bioequivalent to $Allegra^{(R)}$ tablet.