• Analytical Science and Technology
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• v.6 no.1
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• pp.57-63
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• 1993

Spectrophotometric determination of cobalt by flow injection method is described. 2-(5-Bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) aniline rapidly forms a water-soluble complex with cobalt in $NH_3-NH_4Cl$ buffer solution at pH 10.5. The absorption maxima of this complex is at 545 nm with molar absorptivity of $58000L\;mol^{-1}\;cm^{-1}$. The calibration curve of cobalt is linear over the range of 0.1 to 0.6ppm and the detection limit is 25ppb. The relative standard deviation is ${\pm}0.72%$ for 0.5ppm and the sampling rate is $60samples\;hr^{-1}$. The interfering effect of some cations and anions was investigated. Ni(II), Cu(II), Fe(III) and $CN^-$ interfered severely. The interfering effect of these matallic ions could be decreased by adding $1.0{\times}10^{-3}M$ EDTA solution to the carrier stream.

• Korean Journal of Microbiology
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• v.33 no.3
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• pp.187-192
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• 1997

The strain producing biosurfactant was isolated from soil. The isolated strain was identified as the genus Tsukamurella through its morphological, cultural, physiological, menaquinone type, fatty acid composition characteristics. The highest biosurfactant production by Tsukamurella sp. 26A was observed after 4 days cultivation in the culture medium containing n-hexadecane 7%, $NaNO_{3}$ 0.2%, $K_2HPO_4$ 0.001%, $MgSO_{4}$ center dot $7H_{2}O$ 0.02%, $CaCl_2$ center dot $2H_{2}O$ 0.02%, yeast extract 0.02%(pH 6.8-7.0, 30^{\circ}C.$ The surface and interfacial tension of an aqueous solution reached 30 mNim and 1.5 mNim, respectively. The biosurfactant stabilized oil-in-water emulsion with a variety of hydrocarbons, edible oils and petroleum oils.

• Bulletin of the Korean Chemical Society
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• v.20 no.5
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• pp.535-538
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• 1999

Five coordinated water-soluble iridium(l) complex, IrH(CO)(TPPTS)3 (1) (TPPTS = P(m-C6H4SO3Na)3-xH2O) has been prepared from the reaction of IrCl3·3H2O with TPPTS and HCHO in H2O/EtOH solution. Complex 1 catalyzes the hydration of nitrites (RC ≡ N, R = CH3, CICH2, CH3(CH2)4, Ph) in aqueous solution to give the corresponding amides (RCONH2) at 100℃. The hydration of unsaturated nitrites (R'C ≡ N, R'=CH3CH=CH, CH3OCH=CH, trans-PhCH=CH, CH2=C(CH3)) takes place regioselectively on-C ≡ N group to give unsaturated amides (R'CONH2) leaving the olefinic group intact. The yields of the amides seem to be depending on the electrophilicity of the carbon of nitrile: The more the electron withdrawing ability of the substituents on nitrites, the more amides are obtained. The hydration of dinitriles (NC-R-CN, R=(CH2)4, (CH2)6) with complex 1 initially gives mono-hydration products (NC-R-CONH2) which are slowly hydrated further to give dihydration products (H2NCO-R-CONH2). The hydration of 1,4-dicyanobutane has been found to be somewhat faster than that of 1,6-dicyanohexane.

• YAKHAK HOEJI
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• v.22 no.1
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• pp.1-7
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• 1978

Two yellowish oily liquid compounds, $C_{6}H_{6}O_{3}$(A) bp $189^{\circ}$, $n^{20}_{D}$ 1.3697 and $C_{7}H_{8}O_{3}$(D) bp $164^{\circ}$, $n^{20}_{D}$1.5075, were isolated from root of Codonopsis pilosula (Franch.) Nannfeldt (Campanulaceae). Their structures were identified as 5-(hydroxymethyl)-2-furaldehyde(A) and 5-(methoxymethyl)-2-furaldehyde(D). The latter is a new compound among the known natural products.

• Tuberculosis and Respiratory Diseases
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• v.72 no.6
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• pp.493-500
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• 2012

Background: This study investigated the clinical characteristics and risk factors of the severity of pandemic influenza A (H1N1) 2009 infection in pediatric patients in Busan and Gyeongsangnam-do. Methods: Cases of influenza A (H1N1) 2009 in patients under the age of 18 years, confirmed by reverse transcription polymerase chain reaction, at Pusan National University Hospital and Pusan National University Yangsan Hospital from the last week of August 2009 through the last week of February 2010 were retrospectively analyzed. Results: Of the 3,777 confirmed cases of influenza A (H1N1) 2009, 2,200 (58.2%) were male and 1,577 (41.8%) were female. The average age of the patients was $8.4{\pm}4.8$ years. The total cases peaked during 44th to 46th week. Most of the patients were in the 5- to 9-year-old age group. Oseltamivir was administered to 2,959 (78.3%) of the patients. 221 patients (5.9%) were hospitalized, age an average of $6.7{\pm}4.5$ years. The average duration of hospitalization was $7.4{\pm}5.6$ days. One hundred cases (45.2%) had pneumonia. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. Children with asthma were at very high risk of hospitalization, over 20 times the non-asthmatic children (odds ratio [OR], 21.684; confidence interval [CI], 13.295~39.791). Likewise the children with neurologic deficits faced a 16 times higher risk (OR, 15.738; CI, 7.961~31.111). Ten of the patients (4.5%) were admitted to the intensive care unit, and eight (3.6%) required mechanical ventilation. Conclusion: Of the pediatric patients with pandemic influenza A (H1N1) 2009, most of the patients were in the 5- to 9-year-old age group. Risk factors for hospitalization included male gender, <2 years of age, and underlying disease. The most common complication was pneumonia. The very high risk of severe morbidity in children with asthma or neurologic disease shows the critical importance of targeted vaccine coverage, special awareness and swift care by both guardians and primary care providers.

• Bulletin of the Korean Chemical Society
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• v.16 no.10
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• pp.912-915
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• 1995

Ornidazole, C7H10ClN3O3, crystallizes in the triclinic, space group P1^, with a=13.605(2), b=14.054(1), c=8.913(5) Å, α=71.59(2), β=78.73(2), γ=64.86(1)°, μ=3.26 cm-1, Dc=1.499 g/cm3, Dm=1.497g/cm3, F(000)=684, and z=6. Intensities for 2693 unique reflections were measured on a CAD4 diffractometer with graphite-monochromated Mo-Kα radiation. The structure was solved by direct method and refined by block-diagonal least squares to a final R of 0.081 (Rw=0.047) for 1952 reflections with Fo>3σ (Fo). The asymmetric unit contains three independent molecules of the title compound. The bond lengths and bond angles are comparable with the values found in the other nitro-substituted compounds. The nitro groups are rotated (6.9°, 6.6°, 2.6° for the three independent molecule, respectively) about the C-N axes from the imidazole planes. The crystal structures are linked by two intermolecular hydrogen bonds of O-H---N type and one intermolecular hydrogen bond of O-H---O type.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.1
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• pp.5-7
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• 2002

For quantitative N depth profiling, N profiles were measured in a～3 m Si oxynitride by low energy O$\sub$2+/sputtering and the result was calibrated with MEIS analysis of the N thickness and areal density. The quantitative depth profile of nitrogen showed the pileup of nitrogen atoms at the interface of ultrathin oxynitride films.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.894-898
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• 2011

The first example of lead compound from $Pb(NO_3)_2$ and $H_3L$ N-heterocyclic ligand $(H_3L\;=\;(HO_2C)_2(C_3N_2)(C_3H_7)CH_2(C_6H_4)(C_6H_3)CO_2H)$, $[Pb_4(L')_4]{\cdot}5H_2O$ 1 (L' = OOC$(C_3H_7)(C_3N_2)CH_2(C_6H_4)(C_6H_3)COO)$, has been obtained under hydrothermal condition by decarboxylation, and characterized by elemental analysis, IR, TGDTA, and single-crystal X-ray diffraction. Compound 1 possesses a rare two-dimensional upper-lower offset terrace-like layer structure. In 1, crystallographic distinct Pb(II) ion adopts five-coordination geometry, and two lattice water molecules occupy the voids between 2-D layers. Results of solid state fluorescence measurement indicate that the emission band 458 nm may be assigned to $\pi^*-n$ and $\pi^*-\pi$ electronic transitions within the aromatic systems of the ligand L', however, the emission bands centred at 555 nm, 600 nm and 719 nm may be derived from phosphorescent emission ($\lambda_{excitation}$ = 390 nm).

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1786-1793
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• 2005

The study compared the fatty acid profiles of 3 muscles (Longissimus dorsi, LD, Triceps brachii, TB and Semimembranosus, SM) obtained from Korean Hanwoo (18 steers, 24 months old) and Australian Angus beef (18 steers, 24 months old) and assessed their role in sensory perception. The samples of each carcass were prepared in the same manner, and cooked both as traditional grilled steaks and Korean BBQ style. A total of 720 Korean sensory panelists evaluated the beef samples for tenderness, juiciness, flavor, and overall liking. Oleic acid (18:1) was significantly (p<0.05) higher in TB than that in LD and SM. The essential linoleic acid (C18:2) was significantly (p<0.05) higher in TB and SM than that in LD. For LD muscle, the proportion of saturated fatty acids was significantly (p<0.05) highest, while that of polyunsaturated fatty acids was lowest among the three muscles. Australian Angus beef had significantly (p<0.05) higher n-3 PUFA than that of the Korean Hanwoo for the three muscles, while the latter contained significantly (p<0.05) higher n-6 PUFA than that of the former. The clustering analysis showed that there a was significant difference in fatty acids such as C16:0, C16:1n7, C18:0, C18:2n6, C18:3n3, C20:3n6, C20:4n6, C22:4n6, and C22:5n3 for sensory perception (tenderness, juiciness, flavor and overall likeness) of the beef from two origins (p<0.05) among three clusters. Especially, C14:0 had a significant effect on sensory perception only for Korean Hanwoo beef; while C20:5n3 had a significant (p<0.05) effect only for Australian Angus beef based on clustering with the sensory variables.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.6
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• pp.737-741
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• 1996

Dry matter yield of reed canarygrass was investigated in uncultivated rice paddy in Korea, and an attempt was made to estimate the most economic and efficient cutting frequency and rates of nitrogen (N) fertilization, for increased production of reed canarygrass. Total dry matter yields of reed canarygrass per year were 7.4-15.7, 8.5-16.1, and 7.5-13.4 tons/ha in 3, 4, and 5 cutting frequencies, respectively, and over the N treatments of 0-120 kg N/ha/cut. When cut 3 or 5 times annually, the 2nd cut produced the highest proportion of total yield at 38.4 and 33.0%, respectively, when cut 4 times the 3rd cut was highest (38.3%). The ranges of economic N level, limiting N level and efficiency of dry matter production were 243.3-293.0, 387.2, and 14.6 kg DM/kg N, respectively. These indicators were particularly low for the 5 cutting frequency possibly because of the unusually high temperature in the summer season. The best cutting frequency for the dry matter production of reed canarygrass in 1994 was 3 per year because of the higher efficiency of dry matter production.