• The Korean Journal of Air & Space Law and Policy
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• v.35 no.2
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• pp.247-280
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• 2020

For customs-free and liberalization on the trade of aircraft parts, the WTO Agreement on Trade in Civil Aircraft was separately concluded as plurilateral trade agreement at the time of launching WTO in 1995, and currently 33 countries including the United States and the EU are acceded but Korea does not. Major details of the Agreement on Trade in Civil Aircraft include product coverage, the elimination of customs duties and other charges, the prohibition of government-directed procurement of civil aircraft, the application of the Agreement on Subsides and Countervailing Measures, and the consultation on issues related to this Agreement and dispute resolution. Article 89 paragraph 6 of the current Customs Act was newly established on December 31, 2018, and the tariff reduction rate for imports of aircraft parts will be reduced in stages from May 2019 and the tariff reduction system will be abolished in 2026. Accordingly, looking at the impact of the Agreement on Trade in Civil Aircraft on the aviation industry, first, as for the impact on the air transport industry, an tariff allotment of the domestic air transport industry is expected to reach about 160 billion won a year from 2026, and upon acceding to the Agreement on Trade in Civil Aircraft, the domestic air transport industry will be able to import aircraft parts at no tariff, so it will not have to pay 3 to 8 percent import duties. Second, as for the impact on the aviation MRO industry, if the tariff reduction system for aircraft parts is phased out or abolished in stages, overseas outsourcing costs in the engine maintenance and parts maintenance are expected to increase, and upon acceding to the Agreement on Trade in Civil Aircraft, the aviation MRO industry will be able to import aircraft parts at no tariff, so it will reduce overseas outsourcing costs. If the author proposes a policy direction for the trade liberalization of aircraft parts to ensure competitiveness of the aviation industry, first, as for the tariff reduction by the use of FTA, in order to be favored with the tariff reduction by the use of FTA, it is necessary to secure the certificate of origin from foreign traders in the United States and the EU, and to revise the provisions of Korea-Singapore and Korea-EU FTA. Second, as for the push of acceding to the Agreement on Trade in Civil Aircraft, it would be resonable to push the acceding to Agreement on Trade in Civil Aircraft for customs-free on the trade of aircraft parts, as the tariff reduction method by the use of FTA has limits. Third, as for the improvement of the tariff reduction system for aircraft parts under the Customs Act, it is expected that there will take a considerable amount of time until the acceding to the Agreement on Trade in Civil Aircraft, so separate improvement measures are needed to continue the tariff reduction system of aircraft parts under Article 89 paragraph 6 of the Customs Act. In conclusion, Korea should accede to the WTO Agreement on Trade in Civil Aircraft to create an environment in which our aviation industry can compete fairly with foreign aviation industries and ensure competitiveness by achieving customs-free and liberalization on the trade of aircraft parts.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.853-860
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• 1997

Background : Chronic cough, defined as a cough persisting for three weeks or longer, is a common symptom for which outpatient care is sought. The most common etiologies of chronic cough are postnasal drip, asthma, and gastroesophageal reflux. Methacholine challenge is a useful diagnostic study in the evaulation of chronic cough, particularly useful in chronic cough patients with asthmatic symptom. Patients with chronic cough may have dysfunction of bronchial and extrathoracic airways. To evaluate if dysfunction of the bronchial and extrathoracic airways causes chronic cough, we assessed bronchial (BHR) and extrathoracic airway (EAHR) responsiveness to inhaled methacholine in patients with chronic cough. Method : 111 patients with chronic cough were enrolled in our study. Enrolled patients had no recorded diagnosis of asthma, bronchopulmonary disease, hypertension, heart disease or systemic disease and no current treatment with bronchodilator or corticosteroid. Enrolled patients consisted of 46 patients with cough alone, 24 patients with wheeze, 22 patients with dyspnea, 19 patients with wheeze and dyspnea. The inhaled methacholine concentrations causing a 20% fall in forced expiratory volume in 1s($PC_{20}FEV_1$) and 25% fall in maximal mid-inspiratory flow ($PC_{25}MIF_{50}$) were used as bronchial and extra thoracic hyperresponsiveness. Results : There were four response patterns to methacholine challenge study : BHR in 27 patients, EAHR in 16 patients, combined BHR and EAHR in 8 patients, and no hyperresponsiveness in 60 patients. In patients with cough alone, there were BHR in 3 patients, EAHR in 9 patients, and combined BHR and EAHR in 2 patients. In patients with wheeze and/or dyspnea, there were BHR in 24 patients, EAHR in 7 patients, and BHR and EAHR in 6 patients. Compared with patients with wheeze and/or dyspnea, patients with cough alone had more common EAHR than BHR. In patients with wheeze and/or dyspnea, BHR was more common than EAHR. Conclusion : These results show that among patients with hyperresponsiveness to methacholine, those with dyspnea and/or wheezing had mainly bronchial hyperresponsiveness, whereas those with chronic cough alone had mainly extrathoracic airway hyperresponsiveness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.826-836
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• 2010

This study was conducted to compare the dietary habits, nutrient intake and health status of female college students at Sahmyook University according to their majors. Specifically, women majoring in literature and science (77), food and nutrition (103) and sport (73) were evaluated. College women in the sports department were more likely to have a part-time job and had greater expenses than women in the other departments. The average height of college women in the sports department (164.3${\pm}$4.6 cm) was 2.04 cm taller than that of women with other majors (162.3${\pm}$4.7 cm). College women in the department of literature and science were more likely to have an unbalanced diet, even though they commonly ate small amounts of fruit as snacks. They were more prone to take nutrient tablets and vitamins when compared to women in the other departments. College women in the department of sport were more likely to have unbalanced meals (31.5%) and to overeat. Students in the department of food and nutrition ate more fruit, vitamin C and E but less cholesterol containing foods (p<0.05), less fast food and fried food than students in the other departments. The subjects in the department of sport ate less bread, sweet potatoes, fast foods and fried foods but more calories, fat, vitamin A, vitamin B, niacin, Ca, P and cholesterol than students in the other departments (p<0.05). They were also more likely to exercise for more than two hours a day. The most common problems among college women were going without meals, eating an unbalanced diet, overeating, intake of ill-balanced nutrients and lack of exercise. It was found that college women in the department of sport had a better intake of nutrients and maintained healthier life styles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.858-868
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• 2008

This study was carried out to investigate the effects of Gastrodiae Rhizoma powder on plasma lipid profiles in elderly volunteers with hyperlipidemia, hypertension, diabetes or heart disease. 32 elderly people, 11 males and 21 females aged $60{\sim}77$ years, were given Gastrodiae Rhizoma powder 15 g twice daily for 6 months. We investigated the antheropometric data, general characteristics and dietary habit by using questionnaires. Fasting blood samples were collected from the subjects before and after this 6 months intervention study. Blood pressure, glucose, hemoglobin and lipid levels of plasma, atherogenic index (AI) and cardiac risk factors (CRF, LHR, HTR) were determined before and after consumption of Gastrodiae Rhizoma powder. The mean body mass index (BMI) of the male and female subjects were 22.4 and 23.6, respectively. The percent of ideal body weight (PIBW) of males and females were 105.6% and 122.3%, respectively. The subjects had decreased intake frequency of fish and meat in their dietary habit. After consumption of Gastrodiae Rhizoma powder, there were no significant differences in blood pressure; however, the blood glucose significantly decreased with Gastrodiae Rhizoma intake in the males. In the subjects, the levels of plasma total cholesterol, triglyceride, and LDL-cholesterol were decreased by the consumption of Gastrodiae Rhizoma powder; while the levels of plasma LDL-cholesterol was significantly decreased in female. Blood pressure and biochemical assessment (blood glucose, hemoglobin, triglyceride, total cholesterol, LDL and HDL-cholesterol) of the subjects were within the normal range. It was found that AI, CRF and LHR were significantly decreased by Gastrodiae Rhizoma intake. The present results indicate that dietary supplementation of Gastrodiae Rhizoma improved lipid metabolism and cardiac risk factor in cardiovascular disease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.371-384
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• 1982

Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.

• Journal of fish pathology
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• v.23 no.1
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• pp.57-67
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• 2010

Effects of temperature ($13{\pm}1.5^{\circ}C$, $23{\pm}1.5^{\circ}C$) on the pharmacokinetic properties of nalidixic acid (NA), piromidic acid (PA) and oxolinic acid (OA) were studied after oral administration to cultured olive flounder, Paralichthys olivaceus. Serum concentrations of these antimicrobials were determined after oral administration of a single dosage of 60 mg/kg body weight (average 700 g). At $23{\pm}1.5^{\circ}C$, the peak serum concentrations of NA, PA and OA, which attained at 10 h, 24 h and 30 h post-dose, were 11.55, 3.79 and $1.12{\mu}g/m\ell$, respectively. At $13{\pm}1.5^{\circ}C$, the peak serum concentrations of NA, PA and OA, which attained at 10 h, 15 h and 30 h post-dose, were 6.36, 1.4 and $1.01{\mu}g/m\ell$, respectively. Better absorption of NA and PA was noted at $23{\pm}1.5^{\circ}C$ compared to $23{\pm}13^{\circ}C$. The elimination of NA from serum of olive flounder was considerably faster at $23{\pm}1.5^{\circ}C$ than at $13{\pm}1.5^{\circ}C$. However, both absorption and elimination of OA were not affected significantly by temperature. The kinetic profile of absorption, distribution and elimination of these antimicrobials in serum were analyzed by fitting to a one- and two compartment model, with WinNonlin program. In the one compartment model for NA, AUC, Tmax and Cmax at $23{\pm}1.5^{\circ}C$ were $258.26{\mu}g{\cdot}h/m\ell$, 10.67 h and $8.91{\mu}g/m\ell$, respectively. The AUC, $T_{max}$ and $C_{max}$ at $13{\pm}1.5^{\circ}C$ were $341.45 {\mu}g{\cdot}h/m\ell$, 7.72 h and $6.23{\mu}g/m\ell$, respectively. In the one compartment model for PA, AUC, $T_{max}$ and $C_{max}$ at $23{\pm}1.5^{\circ}C$ were $248.12{\mu}g{\cdot}h/m\ell$, 21.15 h and $3.09{\mu}g/m\ell$, respectively. The AUC, $T_{max}$ and $C_{max}$ at $13{\pm}1.5^{\circ}C$ were $103.89{\mu}g{\cdot}h/m\ell$, 12.89 h and $1.22{\mu}g/m\ell$, respectively. In the two compartment model for OA, AUC, $T_{max}$ and $C_{max}$ at $23{\pm}1.5^{\circ}C$ were $138.20{\mu}g{\cdot}h/m\ell$, 23.95 h and $1.06{\mu}g/m\ell$, respectively. The AUC, $T_{max}$ and $T_{max}$ at $13{\pm}1.5^{\circ}C$ were $159.10{\mu}g{\cdot}h/m\ell$, 28.03 h and $1.02{\mu}g/m\ell$, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.259-264
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• 2002

DK 754S, a forage corn hybrid is bred by Dekalb plant Genetics Co.. Garst 8255 by Garst Seeds Co., and GW 737 by Crosbyton Co. in US, respectively. These have been tested in Suwon and Chonan for 3 years to test their regional yield trial. In result, we were able to confirm the excellence of above cultivars and these were selected as new recommended cultivars April of 2002 by NACF. The characteristics of these cultivars are as follows ; 1. DK 7545 a. This cultivar is mid-late maturing, high quality, high yielding forage corn hybrid. Its mean tasseling date is the 11th of July. It takes 78 days from emergence to tasseling date, which is almost same with Kwanganok. The culm length and the ear height are 231 cm and 127 cm. It is relatively strong to lodging. b. The color of ear is yellow, the number of ear row is nineteen. DK 7545 shows strength to H maydis and MBSDV has occurred between 0% and 4.1% in Chonan test area but it still does not affect yielding at all. It is relatively resistant to corn borer and its stay green is almost same level comparing to a check hybrid, Kwanganok. c. Dry matter yield of this cultivar is 19.6 tons, TDN is 13.4 tons per a ha, therefore these hybrids are increased by from 6 to 9% comparing to Kwanganok. The percent ear among total dry matters yield is 43.7%. 2. Garst 8255 a. This hybrid is mid-late maturing, high quality, high yielding forage corn like as Kwanganok. Its the mean tasseling date and the period from emergence to tasseling date are almost same with a check hybrid, Kwanganok. The Culm length and the ear height are 259 cm, and 146 cm which are tall. It resists to lodging and shows excellence of stay green. b. Garst 8285 resists to H maydis, and MBSDV, and corn borer as much as Kwanganok has. c. Dry matter yield of this cultivar is 21,735 kg. TDN is 14,627 kg per a ha, therefore this is increased by 21%, 16%, respectively, comparing to a check hybrid, Kwanganok. The percent ear among total dry matters yield is 44.2%. 3. GW 737 a. This hybrid is mid-late maturing, high quality, high yielding forage com hybrid like as Kwanganok. Its mean tasseling date is 13th of July which is 2 days late comparing with a check hybrid, Kwanganok and the period from emergence to tasseling date is 80 days. b. The culm length and the ear height are 274 cm and 150 cm, which are tall. It resists to lodging moderately and shows excellence of stay green. c. GW 737 resists to H maydis and MBSDV very well, corn borer moderately resistance. d. Dry matter yield of this cultivar is 18,025kg, TDN 15,164kg per a ha, therefore this hybrid remarkably increased by 26%, 20%, respectively, comparing to a check hybrid, Kwanganok.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.57-61
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• 2012

Purpose: The multi-gated cardiac blood pool scan is to evaluate the function of left ventricle (LV) and usefully observe a value of ejection fraction (EF) for a patient who is receiving chemotherapy. To calculate LVEF, we should adjust an angle of left anterior oblique (LAO) view to separate both ventricles. And by overlapped ventricles, it is possible to affect LVEF. The purpose of this study is to investigate and compare quantitative indices by changing an angle of LAO view. Materials and methods: We analyzed the 49 patients who were examined by multi-gated cardiac blood pool scan in department of nuclear medicine at Asan Medical Center from June to September 2011. Firstly, we acquired "Best septal" view. And then, we got images by addition and subtraction of angle for LAO view to anterior and lateral. We compared three LAO views for 20 people by 5 degrees and 39 people by 10 degrees. And we analyzed quantitative indices, EF, end diastole and end systole counts, by automated and manual region of interest (ROI) modes. Results: Firstly, we analyzed quantitative indices by automated ROI mode. In case of 5 degrees, the averages of EF are $61.0{\pm}7.5$, $62.1{\pm}7.1$, $60.9{\pm}6.7%$ ($p$=0.841) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $62.4{\pm}9.5$, $62.3{\pm}10.8$, $61.6{\pm}.9.3%$ ($p$=0.938) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Secondly, we analyzed quantitative indices by manual ROI mode. In case of 5 degrees, the averages of EF are $62.8{\pm}7.1$, $63.6{\pm}7.5$, $62.7{\pm}7.3%$ ($p$=0.903) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $65.5{\pm}9.0$, $66.3{\pm}8.7$, $63.5{\pm}.9.3%$ (p=0.473) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Conclusion: When an image is nearly "Best septal" view, the difference of LAO angle would not affect to change LVEF. Although there was no difference in quantitative analysis, deviations could happen when to interpret wall motion qualitatively by reading physicians.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.172-176
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• 2010

Purpose: The patients' moves occurred at PET/CT scan will cause the decline of correctness in results by resulting in inconsistency of Attenuation Correction (AC) and effecting on quantitative evaluation. This study has evaluated the utility of reconstruction method using AC position changing method when having inconsistency of AC depending on the position change of emission scan after transmission scan in obtaining PET/CT 3D image. Materials and Methods: We created 1 mL syringe injection space up to ${\pm}2$, 6, 10 cm toward x and y axis based on central point of polystyrene ($20{\times}20110$ cm) into GE Discovery STE16 equipment. After projection of syringe with $^{18}F$-FDG 5 kBq/mL, made an emission by changing the position and obtained the image by using AC depending on the position change. Reconstruction method is an iteration reconstruction method and is applied two times of iteration and 20 of subset, and for every emission data, decay correction depending on time pass is applied. Also, after setting ROI to the position of syringe, compared %Difference (%D) at each position to radioactivity concentrations (kBq/mL) and central point. Results: Radioactivity concentrations of central point of emission scan is 2.30 kBq/mL and is indicated as 1.95, 1.82 and 1.75 kBq/mL, relatively for +x axis, as 2.07, 1.75 and 1.65 kBq/mL for -x axis, as 2.07, 1.87 and 1.90 kBq/mL for +y axis and as 2.17, 1.85 and 1.67 kBq/mL for -y axis. Also, %D is yield as 15, 20, 23% for +x axis, as 9, 23, 28% for -x axis, as 12, 21, 20% for +y axis and as 8, 22, 29% for -y axis. When using AC position changing method, it is indicated as 2.00, 1.95 and 1.80 kBq/mL, relatively for +x axis, as 2.25, 2.15 and 1.90 kBq/mL for -x axis, as 2.07, 1.90 and 1.90 kBq/mL for +y axis, and as 2.10, 2.02, and 1.72 kBq/mL for -y axis. Also, %D is yield as 13, 15, 21% for +x axis, as 2, 6, 17% for -x axis, as 9, 17, 17% for +y axis, and as 8, 12, 25% for -y axis. Conclusion: When in inconsistency of AC, radioactivity concentrations for using AC position changing method increased average of 0.14, 0.03 kBq/mL at x, y axis and %D was improved 6.1, 4.2%. Also, it is indicated that the more far from the central point and the further position from the central point under the features that spatial resolution is lowered, the higher in lowering of radioactivity concentrations. However, since in actual clinic, attenuation degree increases more, it is considered that when in inconsistency, such tolerance will be increased. Therefore, at the lesion of the part where AC is not inconsistent, the tolerance of radioactivity concentrations will be reduced by applying AC position changing method.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.1
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• pp.40-46
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• 2013

The isotope ratios of $^{13}C/^{12}C$ and $^{18}O/^{16}O$ for a sample in a mass spectrometer are measured relative to those of a pure $CO_2$ reference gas (i.e., laboratory working standard). Thus, the calibration of a laboratory working standard gas to the international isotope scales (Pee Dee Belemnite (PDB) for ${\delta}^{13}C$ and Vienna Standard Mean Ocean Water (V-SMOW) for ${\delta}^{18}O$) is essential for comparisons between data sets obtained by other groups on other mass spectrometers. However, one often finds difficulties in getting well-calibrated standard gases, because of their production time and high price. Additional difficulty is that fractionation processes can occur inside the gas cylinder most likely due to pressure drop in long-term use. Therefore, studies on laboratory production of pure $CO_2$ isotope standard gas from stable solid calcium carbonate standard materials, have been performed. For this study, we propose a method to extract pure $CO_2$ gas without isotope fractionation from a solid calcium carbonate material. The method is similar to that suggested by Coplen et al., (1983), but is better optimized particularly to make a large amount of pure $CO_2$ gas from calcium carbonate material. The $CaCO_3$ releases $CO_2$ in reaction with 100% pure phosphoric acid at $25^{\circ}C$ in a custom designed, evacuated reaction vessel. Here we introduce optimal procedure, reaction conditions, and samples/reactants size for calcium carbonate-phosphoric acid reaction and also provide the details for extracting, purifying and collecting $CO_2$ gas out of the reaction vessel. The measurements for ${\delta}^{18}O$ and ${\delta}^{13}C$ of $CO_2$ were performed at Seoul National University using a stable isotope ratio mass spectrometer (VG Isotech, SIRA Series II) operated in dual-inlet mode. The entire analysis precisions for ${\delta}^{18}O$ and ${\delta}^{13}C$ were evaluated based on the standard deviations of multiple measurements on 15 separate samples of purified $CO_2$. The pure $CO_2$ samples were taken from 100-mg aliquots of a solid calcium carbonate (Solenhofen-ori $CaCO_3$) during 8-day experimental period. The multiple measurements yielded the $1{\sigma}$ precisions of ${\pm}0.01$‰ for ${\delta}^{13}C$ and ${\pm}0.05$‰ for ${\delta}^{18}O$, comparable to the internal instrumental precisions of SIRA. Therefore, we conclude the method proposed in this study can serve as a way to produce an accurate secondary and/or laboratory $CO_2$ standard gas. We hope this study helps resolve difficulties in placing a laboratory working standard onto the international isotope scales and does make accurate comparisons with other data sets from other groups.