• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.393-397
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• 2008

Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the presence of germanium and phosphorus in a pure gold bonding wire. The samples were dissolved with hydrobromic acid and nitric acid at room temperature. The quantitation limits were 0.012 mg L-1 at 265.118 nm for Ge and 0.009 mg L-1 at 177.495 nm for P. Using the mixed acid digestion formula of DIW+HBr+HNO3, the recoveries were in the range of 98-100% and the relative standard deviation was within 1.1-2.3%. On the other hand, the amount of Ge decreased by about 16.2% using DIW+HCl+HNO3, due to the formation of a volatile compound. The Ge contents determined using the external method and the standard addition method were 9.45 mg kg-1 and 9.24 mg kg-1, respectively, and the P contents, using the same methods, were 22.49 mg kg-1 and 23.09 mg kg-1, respectively. Both methods were successfully used to determine the trace amounts of P and Ge in the pure gold bonding wire samples.

• 대한의용생체공학회:의공학회지
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• 제22권4호
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• pp.311-319
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• 2001

Statistical reconstruction methods in the context of a Bayesian framework have played an important role in emission tomography since they allow to incorporate a priori information into the reconstruction algorithm. Given the ill-posed nature of tomographic inversion and the poor quality of projection data, the Bayesian approach uses regularizers to stabilize solutions by incorporating suitable prior models. In this work we show that, while the quantitative performance of the standard filtered backprojection (FBP) algorithm is not as good as that of Bayesian methods, the application of spline-regularized smoothing to the sinogram space can make the FBP algorithm improve its performance by inheriting the advantages of using the spline priors in Bayesian methods. We first show how to implement the spline-regularized smoothing filter by deriving mathematical relationship between the regularization and the lowpass filtering. We then compare quantitative performance of our new FBP algorithms using the quantitation of bias/variance and the total squared error (TSE) measured over noise trials. Our numerical results show that the second-order spline filter applied to FBP yields the best results in terms of TSE among the three different spline orders considered in our experiments.

• Environmental Analysis Health and Toxicology
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• 제18권3호
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• pp.199-208
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• 2003

A new technique was proposed for the determination of alkylphenols, chlorophenols and bisphenol A in tap water samples. The sample preparation consists of a solid phase extraction (SPE) of alkylphenols, chlorophenols and bisphenol A from a water sample with XAD-4 and subsequent conversion to isobutyloxycarbonyl (isoBOC) derivatives or tert-butyldimethylsilyl (TBDMS) derivatives for sensitive analysis with the CC/MS SIM mode. The recoveries were 86.6 ∼ 105.2％ (isoBOC derivatization) and 97.6∼484.5％ (TBDMS derivatization), respectively. The limit of quantitation of alkylphenols, chlorophenols and bisphenol h for SIM were 0.001∼0.050 $\mu\textrm{g}$/1 (isoBOC derivatization) and 0.003∼0.050 $\mu\textrm{g}$/1 (TBDMS derivatization). The SIM responses were linear with the correlation coefficient varying 0.9755∼0.9981 (isoBOC derivatization), and 0.9908∼0.9996 (TBDMS derivatization). When these methods were applied to tap water samples, the range of concentrations were 22.8∼31.3 ng/1 in 2,4-dichlorophenol, 28.6∼70.3 ng/1 in pentachlorophenol, 15.2∼17.4 ng/1 in t-butylphenol, 10.8∼13.2 ng/1 in t-octylphenol and 17.6∼36.3 ng/l in bisphenol A, respectively.

• 한국식품과학회지
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• 제27권4호
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• pp.605-611
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• 1995

호남지방에서 생산된 6점의 토종꿀을 대상으로 disaccharides와 trisaccharides를 분취한 다음 GC와 HPLC를 이용하여 각 oligosaccharides를 분리, 정량하였다. disaccharides는 토종꿀 중에 $5.9{\sim}8.4%$ 범위로 함유되어 있었는데 GC로 분석한 결과 sucrose, nigerose, maltose, laminaribiose, turanose, kojibiose, palatinose 및 isomaltose 등 8개의 당류가 분리되었으며, 그 중 maltose가 평균 2.28%로 가장 많이 함유되어 있었으며 그 다음으로 turanose가 평균 1.57%의 함량을 나타냈다. trisaccharides는 토종꿀 중에 $1.4{\sim}5.4%$ 범위로 함유되어 있었는데 isopanose, erlose, theanderose, maltotriose, panose 등 5개의 당류가 분리되었으며, 그 중 erlose가 평균 2.83%로 가장 많은 부분을 차지하고 있었다. 토종꿀중에 함유되어 있는 전체 oligosaccharides의 조성을 살펴보면 erlose가 가장 많이 함유되어 있었으며 maltose, turanose, sucrose, isomaltose의 순서로 많이 함유되어 있었다.

• 한국농촌건축학회논문집
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• 제19권4호
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• pp.77-85
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• 2017

In order to preserve beautiful coastal areas landscapes of Jeju Island's the landscape resource, Jeju Special Self-Governing Province is dedicated to protecting the landscape through legal regulations and deliberations. However, the Coastal Landscape of Jeju Island was continuously damaged by due to increased tourist and high development pressure. Based on buildings along the Coastal Road in Aeowal of Jeju Island, this study focused on Management Status of Coastal Areas Landscapes through the Analysis of Building Landscape Elements. As a result, 1) It was effective to limit the use and scale of buildings through legal regulations such as Use zoning. 2) The result of analysis on the physical landscape elements of buildings showed some of the them have the damage values despite passing the review of Architecture Committee. Therefore Landscape Policies required institutional maintenance. 3) As physical landscape Elements of buildings is a minimum quantitation criterion of not less than 1.5 for D/H, or less than a factor of $27^{\circ}$ for angle of elevation and not less than 7.8m for elevation blockage ratio was presented as a criterion for preventing damage to the minimum Coastal Landscape.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3603-3609
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• 2011

A novel sampling method of the headspace poly(dimethylsiloxane) (PDMS) mini-disk extraction (HS-PDE) was developed, optimized, validated and applied for the GC/MS analysis of spices flavors. A prototype PDMS mini-disk (8 mm outer diameter, 0.157 mm thickness, 9.4 mg weight) has been designed and fabricated as a sorption device. The technique uses a small PDMS mini-disk and very small volume of organic solvent and less sample size than the solvent extraction. This new HS-PDE method is very simple to use, inexpensive, rapid, requires less labor. Linearities of calibration curves for ${\alpha}$-pinene, ${\beta}$-pinene, limonene and ${\gamma}$-terpinene by HS-PDE combined with GC/MS were excellent having $r^2$ values greater than 0.99 at the dynamic range of 6.06~3500 ng/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) showed very low values. This method exhibited good precision and accuracy. The overall extraction efficiency of this method was evaluated by using partition coefficients ($K_p$) and concentration factors (CF) for several characteristic components from nutmeg and mace. Partition coefficients were in the range from $2.04{\times}10^4$ to $4.42{\times}10^5$, while CF values were 0.88-15.03. HS-PDE was applied successfully for the analysis of flavors compositions from nutmeg, mace and cumin. The HS-PDE method is a very promising sampling technique for the characterization of volatile flavors.

• 대한임상독성학회지
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• 제15권2호
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• pp.101-106
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• 2017

Purpose: This study examined the patterns of drugs, poisons, and chemicals detected in autopsy samples performed in the Seoul Institute and other regional forensic offices of the National Forensic Service (NFS) between 2014 and 2016. Methods: The investigation carried out using the laboratory information management system. Forensic toxicological identification and quantitation were performed in autopsy samples, including heart blood, peripheral blood, liver, kidney, vitreous humor and etc. Gas chromatography/mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to analyze the drugs and poisons. Results: Forensic autopsies were performed on 9,674 cases in this period. Based on the autopsy reports, 699 cases (7.2%) were considered as unnatural deaths caused by fatal intoxication. The number of male deaths was higher than that of female deaths, with the age of 50-59 being the most common age group. Conclusion: Drugs comprised the largest number of deaths due to poison, followed by alcohol, agrochemicals, drug with alcohol, carbon monoxide, and cyanide, in that order. Zolpidem was the most frequently used drug in all drug-related intoxication cases.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1967-1971
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• 2012

A hexavalent chromium (Cr (VI)) is one of the hazardous substances regulated by the RoHS. The determination of Cr (VI) in various polymers and printed circuit board (PCB) has been very important. In this study, the three different analytical methods were investigated for the determination of a hexavalent chromium in Acrylonitrile Butadiene Styrene copolymer (ABS) and PCB. The results by three analytical methods were obtained and compared. An analytical method by UV-Visible spectrometer has been generally used for the determination of Cr (VI) in a sample, but a hexavalent chromium should complex with diphenylcarbazide for the detection in the method. The complexation did make an adverse effect on the quantitative analysis of Cr (VI) in ABS. The analytical method using diphenylcarbazide was also not applicable to printed circuit board (PCB) because PCB contained lots of irons. The irons interfered with the analysis of hexavalent chromium because those also could complex with diphenylcarbazide. In this study, hexavalent chromiums in PCB have been separated by ion chromatography (IC), then directly and selectively detected by inductively coupled plasma atomic emission spectrometry (ICP-AES). The quantity of Cr (VI) in PCB was 0.1 mg/kg.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.77-82
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• 2009

Thrombin activatable fibrinolysis inhibitor (TAFI) also known as plasma procarboxypeptidase B or U is a 60 kD glycoprotein, which is the major modulator of fibrinolysis in plasma. TAFI is a proenzyme, which is activated by proteolytic cleavage to an active carboxypeptidase B-like enzyme (TAFIa, 35.8 kD) by thrombin/thrombomodulin and plasmin. Modulation of fibrinolysis occurs when TAFIa enzymatically removes C-terminal lysine residues of partially degraded fibrin, thereby inhibiting the stimulation of tissue plasminogen activator (t-PA) modulated plasminogen activation. TAFIa undergoes a rapid conformational change at $37{^{\circ}C}$ to an inactive isoform called TAFIai. Potato tuber carboxypetidase inhibitor (PTCI) was shown to specifically bind to TAFIa as well as TAFIai. In this study, a novel immunoassay TAFIa/ai ELISA was used for quantitation of the two TAFI activation isoforms TAFIa and TAFIai. The ELISA utilizes PTCI as the capture agent and a double antibody sandwich technique for the detection. Low levels of TAFIa/ai antigen levels were detected in normal plasma and elevated levels were found in hemophilia A plasmas. TAFIa/ai antigen represents a novel marker to monitor fibrinolysis and TAFIa/ai ELISA may be a valuable assay for studying the role of TAFI in normal hemostasis and in pathological conditions.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2675-2679
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• 2009

This paper reports the example of headspace mulberry paper bag micro solid phase extraction (HS-MPB-$\mu$-SPE) as a new sampling method for the determination of volatile flavor composition of coriander seeds. Adsorption efficiencies between two configurations of mulberry paper bag were compared, and several parameters affecting the HS-MPB-$\mu$-SPE were investigated and optimized. The optimized technique uses an adsorbent (Tenax TA, 0.1 mg) contained in a mulberry paper bag of front configuration where fine surface was outside, and minimal amount of organic solvent (0.6 mL). Linalool and $\gamma$-terpinene were found as abundant flavor compounds from coriander seeds. The limit of detection (LOD) and the limit of quantitation (LOQ) for linalool of major flavor in coriander seeds were 10.3 ng/mL and 34.4 ng/mL, respectively. The proposed method showed good reproducibility and good recovery. The HS-MPB-$\mu$-SPE is very simple to use, inexpensive, requires small sample amounts and solvent consumption. Because the solvent for extraction is reduced to only a very small volume, there is minimal waste or exposure to toxic organic solvent and no further concentration step.