• 한국수소및신에너지학회논문집
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• 제13권3호
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• pp.224-232
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• 2002

CdS-$TiO_2$ nano-composite sol was prepared by the sol-gel method in organic solvents at room temperature and further hydrothermal treatment at various temperatures to control the physical properties of the primary particles. Again, CdS-$TiO_2$ composite particulate films were made by casting CdS-$TiO_2$ sols onto $F:SnO_2$ conducting glass and then heat-treatment at $400^{\circ}C$. Physical properties of these 61ms were further controlled by the surface treatment with $TiCl_4$, aqueous solution. The photo currents and hydrogen production rates measured under the experimental conditions varied according to the $CdS/[CdS+TiO_2]$ mole ratio and the mixed-sol preparation method. For $CdS-TiO_2$ composite sols prepared in IPA, CdS particles were homogeneously surrounded by $TiO_2$ particles. Also, the surface treatment with $TiCl_4$ aqueous solution caused a considerable improvement in the photocatalytic activity, probably as a result of close contacts between the primary particles by the etching effect of $TiCl_4$. It was found that the photoelectrochemical performance of these particulate films could be effectively enhanced by this approach.

• 한국균학회지
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• 제37권1호
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• pp.96-103
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• 2009

병원성 미생물을 방제하기 위하여 국내의 고추 재배지에서 탄저병균에 감염된 고추로부터 Bacillus속 균주를 분리하였다. 이들 중 고추탄저병균인 C. gloeosporioides 균주와 식물에 회색곰팡이병을 일으키는 Botrytis cinerea 균주에 대한 길항작용이 가장 우수한 Bacillus sp. IUB158-03을 선발하였다. 선발된 균주의 형태적, 생리 생화학적 특성과 MicroLog 방법을 이용하여 동정된된 균주는 B. amyloliquefaciens IUB158-03로 명명하였다. 항진균물질 생산을 위한 최적배지 조건은 2% soluble starch, 3% yeast extract, 0.5% tryptone, 0.5% $NH_4H_2PO_4$, 1% NaCl의 pH 6.0에서 $25^{\circ}C$, 72시간 배양한 추출물에서 가장 높은 항진균활성을 나타내었다. B. amyloliquefaciens IUB158-03이 생산한 항진균물질을 butanol로 추출한 후 silica gel column chromatography, preparative thin layer chromatography, and HPLC을 이용하여 항진균물질을 정제하였다. 정제된 항진균물질은 TLC plate 상에서 $R_f$값이 0.27인 것이 확인되었으며, 이 물질은 식물병원균인 Fusarium solani, Rhizoctonia solani, Botrytis cineria, Alternata alternaria와 인체병원성 진균인 Trichophyton mentagrophytes, Epidermophyton floccosum, Cryptococcus neoformans 등에만 선택적으로 높은 항진균 활성을 보였다.

• 생약학회지
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• 제44권4호
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• pp.336-343
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• 2013

In a continuation of investigation on Cordyceps militaris, thirteen compounds were isolated from the $CH_2Cl_2$ and n-BuOH-soluble fraction of C. militaris. They were identified as twelve diketopiperazines such as cyclo($\small{L}$-Gly-$\small{L}$-Pro) (1), cyclo($\small{L}$-Ala-$\small{L}$-Pro) (2), cyclo($\small{L}$-Ser-$\small{L}$-Pro) (3), cyclo($\small{L}$-Val-$\small{L}$-Pro) (4), cyclo($\small{L}$-Thr-$\small{L}$-Pro) (5), cyclo($\small{L}$-Pro-$\small{L}$-Pro) (6), cyclo($\small{L}$-Thr-$\small{L}$-Leu) (7), cyclo($\small{L}$-Tyr-$\small{L}$-Ala) (8), cyclo($\small{L}$-Phe-$\small{L}$-Ser) (9), cyclo($\small{L}$-Phe-$\small{L}$-Pro) (10), cyclo($\small{L}$-Tyr-$\small{L}$-Pro) (11) and brevianamide F (13), and an amino acid, tryptophan (12). Their structures were identified on the basis of chemical evidences and spectroscopic analysis including 1D-NMR ($^1H$, $^{13}C$), 2D-NMR (HSQC, HMBC) and MS spectral data. Among the isolated compounds, compounds 1, 2, 6-11 are first reported from C. militaris.

• 한국식품영양과학회지
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• 제22권4호
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• pp.428-432
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• 1993

국내산 토마토의 품종별 쥬스적성에 대한 기초자료를 얻고져 화학적 성질, 색도, 쥬스의 수율 등의 조사와 관능검사를 하였다. 토마토쥬스의 당도는 지주재배형이 무지주재배형보다 더 높았으며 지주재배형에서는 Jeok Pung과 Master 2가 가장 높은 당도를 보였고, 무지주재배형에서는 79078$\times$ARC가 가장 낮게 나타났다. 산도는 두 재배형간에 유의적인 차이가 없었으나 무지주재배형에서는 Jinhong과 TM103가 가장 높았고, 지주재배형에서는 Jeok Pung이 가장 높게 나타났다. pH는 재배형간에 차이가 없었으며, vitamin C는 무지주재배형에서는 79078$\times$ARC가 가장 높았고 지주재배형에서는 Hong Jho가 가장 높았다. 점도는 무지주재배형에서는 79078$\times$CL1561F$_{6}$이 지주재배형에서는 Hong Jho가 가장 높았다. 쥬스의 색도에서 Dom-inant Wavelength는 무지주재배형의 Good Hope가 가장 긴 파장을 보였고 Y%는 지주재배형의 76Moll-3-1-2-2가 가장 높은 값을 보였다 쥬스의 수율은 무지주재배형에서 Good Hope가 가장 높았고 지주재배형에서 76Moll-3-1-2-2가 가장 낮았다. 관능검사의 결과 색은 무지주재배형이 지주재배형보다 유의적으로 더 높게 평가되었고 지주재배형의 76Moll-3-1-2-2가 가장 낮게 평가되었으며, 향과 맛은 두 재배형간에 유의적인 차이가 없었으나 지주재배형의 Master 2와 76Moll-3-1-2-2가 가장 낮게 평가되었다. 쥬스특성에 가장 적합한 품종은 무지주재배형에서는 Good Hope와 지주재배형에서는 Jeok Pung을 들 수 있다. 그러나 여러 가지 쥬스특성에 대하여는 품종별로 각기 우수성을 보이므로 이들 품종의 적절한 혼합으로 한품종으로 만드는 쥬스보다 우수한 쥬스를 생산할 수 있는 가능성을 보인다.

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.363-367
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• 1992

The crystal structure of (1,3,6,9,11,14-hexaazatricycol[12.2.1.$1^{6,9}$]octadecane)copper(Ⅱ) perchlorate, Cu($C_{12}H_{26}N_6$)$(ClO_4)_2$, has been determined by the X-ray diffraction methods. The crystal data are as follows: Mr=516.9, triclinic, ${\alpha}=8.572\;(2)$, b=8.499 (3), c=15.204 (3) ${\AA}$, ${\alpha}=80.42\;(5),\;{\beta}=73.57\;(3),\;{\gamma}=69.82\;(4)^{\circ},\;V=994.2\;{\AA}^3,\;D_C=1.726\;gcm^{-3}$, space group $P{\tilde{1}},\;Z=2,\;{\mu}=21.27\;cm^{-1}&, F(000)=534 and T=297 K. The structure was solved by direct methods and refined by full-matrix least-squares methods to and R value of 0.081 for 1608 observed reflections measured with graphite-mono-chromated Mo Ka radiation on a diffractometer. There are two independent complexes in the unit cell. The two copper ions lie at the special positions (1/2, 0, 0) and (0, 1/2, 1/2)and each complex possesses crystallographic center of symmetry. Each Cu ion is coordinated to four nitrogen donors if the hexaazamacrotricyclic ligand and weakly interacts with two oxygen atoms of the perchlorate ions to form a tetragonally distorted octahedral coordination geometry. The Cu_N (sec), Cu_N(tert) and Cu_O coordination distances are 1.985 (14), 2.055 (14) and 2.757 (13) ${\AA}$ for the complex A and 1.996 (10), 2.040 (11) and 2.660 (13) ${\AA}$ for the complex B, respectively. The macrocycles in the two independent cations assume a similar conformation with the average r.m.s. deviation of 0.073 ${\AA}$. Two 1,3-diazacyclopentane ring moieties of the hexaazamacrotricyclic ligand are placed oppositely and almost perpendicularly to the square coordination plane of the ruffled 14-membered macrocycle. The secondary N atoms are hydrogen-bonded to the perchlorate O atoms with distances of 3.017 (23) and 3.025 (19) ${\AA}$ for the complexes A and B, respectively.

• 대한화학회지
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• 제30권2호
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• pp.152-158
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• 1986

치환나프톨류(4-Cl-1-naphthol, 6-Br-2-naphthol and $8-NH_2-2-naphthol)$의 해리상수를 온도(25 ~ 40${\circ}C$)와 압력(1~2000bar)을 변화시키면서 분광학적 방법으로 측정했다. 이들의 해리상수는 치환기가 들어가므로서 모두 감소했다. 이것은 치환기의 I-효과로서 설명이 가능했으며 또 온도와 압력이 증가하면 해리상수도 증가하였다. 이들 해리상수로부터 반응의 열역학적 성질을 계산하여 반응의 성질을 알아보았다.

• 자원환경지질
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• 제28권6호
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• pp.541-551
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• 1995

The Yeongdeog gold-silver deposits at Jipum, Gyeongsangbugdo, is of a middle Paleogene $(45.52{\pm}1.02Ma)$ vein type, and is hosted in shale and sandstone of Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, the ore mineralization can be divided into two distinct depositional stages. The early stage is associated with base-metals such as pyrite, arsenopyrite (27.99~30.99 at%), hematite, rutile, pyrrhotite, sphalerite (10.53~18.42 FeS mole%), chalcopyrite and galena with wallrock alteration such as chlorite, sericite and pyrite. The late stage is characterized by the Au-Ag mineralization such as electrum, Ag-bearing tetrahedrite, freibergite, pyrargyrite, unidentified mineral, pyrite, sphalerite (1.08~5.57 FeS mole%), chalcopyrite and galena. Fluid inclusion data indicate that fluid temperatures and salinities range from 343 to $227^{\circ}C$ and from 8.3 to 5.7 wt% eq. NaCl in early stage, respectively. Temperatures and salinities of NaCl eq. wt% range from 299 to $225^{\circ}C$ and from 12.9 to 4.3 in late stage, respectively. They suggest that complex cooling histories were occured by the mixing of the fluids. Sulfur fugacity $(-logfs_2)$ deduced by mineral assemblages and composition ranges from 8.3 to 14.7 atm. in early stage, and from 8.8 to 14.5 atm. in late stage. It suggests that the mineralization was related to decrease of temperature in early stage and fluctuations of $fS_2$ with decrease of temperature in late stage. Sulfur and oxygen isotope compositions are 4.48~5.60‰ and 9.25~10.8% in early stage, and late stage is 4.84~7.00‰ and 5.7‰, respectively. It indicated that hydrothermal fluids may be magmatic origin with some degree of mixing of another water during paragenetic time.

• 한국작물학회지
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• 제49권6호
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• pp.533-538
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• 2004

화성벼와 O. minuta 간 여교잡을 통해 반복친인 화성벼와 출수기, 간장 등 여러 작물학적 특성에서 뚜렷한 차이를 보이는 염색체단편 치환계통 "WH79006"을 육성하였는데 화성벼와 WH79006의 차이는 WH79006에 이입된 O. minuta 염색체 단편에 의한 것이라고 할 수 있다. WH79006이 화성벼의 유전적 배경에 O. minuta의 어느 염색체 단편을 가지고 있는지를 검정하기 위해 SSR마커를 이용하였다. 벼 염색체에 골고루 분포한 294개의 SSR 마커를 검정한 결과 최소한 28개의 이입 단편을 검정하였는데 이들은 2번 염색체를 제외한 모든 염색체에 분포하였으며 전체 길이는 약 168cm이었다. 간장 관여 QTL을 탐색하기 위해 화성벼/WH79006 조합의 75개 $F_2$ 개체를 육성, 간장을 조사하였다. QTL분석 결과 6번 염색체의 RM225부근에서 간장에 관여하는 QTL cl6가 탐지되었다. cl6는 전체 표현형변이의 $9.6\%$를 설명하였으며 O. minute의 대립유전자가 간장을 크게 하는 방향으로 작용하였다. 이 결과는 O. minuta가 포복형임에도 불구하고 간장 조절 유전자들 중에는 간장을 크게 하는 방향으로 작용하는 유전자가 있음을 제시하고 있으며, 이 유전자들은 앞으로 QTL 분석을 통해 그 작용을 밝힐 예정이다. 추후교잡 집단을 이용 O. minuta 특이적 단편들이 어느 형질과 관련이 있는지를 밝힐 예정이다.

• 한국안전학회지
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• 제6권4호
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• pp.13-20
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• 1991

Ion-selective electrode responsive to the thiocynate ion prepared by using the quaternary ammonium salts as a active material and PVC as a membrane matrix. The effect of chemical structure and composition of active material, and the membrane thickness on the linear response. the detection limit, and Nernstian slope of the electrode studied. Under the above optimum conditions of membrane, the effect of pH and the selectivity coefficients to various interfering anions were compared and investigated. It was concluded that the functions of thiocynate ion-selective electrode(ISE) were closely related to the chemical structure of the quaternary ammonium salts. The linear response, and the detection limit of the electrode potential increased with the increase of the carbon chain length of the alkyl group in the quaternary ammonium salts in the ascending order of Aliquat 336T, TOAT, TDAT, and TDDAT. The optimum membrane thickness was 0.3mm. The electrode characteristics was better with the decrease of the concentration of active material, and the best concentration was 3 weight percent. The membrane potential was independent of the pH variation in the region from pH 2 to 12. The order of the selectivity coefficients is as follows：Cl $O_4$$^{[-10]}$ ＞ $I^{[-10]}$ ＞N $O_3$$^{[-10]}$ ＞B $r^{[-10]}$ ＞ $F^{[-10]}$ ＞C $l^{[-10]}$ ＞O $A_{c}$ $^{[-10]}$ 〓S $O_4$$^{2-}$.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1884-1890
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• 2011

A series of Ni(II) and Pd(II) complexes bearing N4-type tetradentate ligands, [Ni($X^1X^2$-6-$Me_2bpb$) 1] and [Pd($X^1X^2$-6-$Me_2bpb$) 2]; 6-$Me_2bpb$ = N,N'-(o-phenylene)bis(6-methylpyridine-2-carboxamidate), $X^1$ = Cl, H, or $CH_3$, $X^2$ = $NO_2$, Cl, F, H, $CH_3$, or $OCH_3$) were designed, synthesized, and characterized to investigate electronic and steric effects of ligand on the norbornene polymerization catalysts. Using modified methylaluminoxanes as an activator, the complexes exhibited high catalytic activities for the polymerization of norbornene and the nickel complexes exhibited better catalytic activity the palladium complexes. Ni complex 1a with $NO_2$ group on the benzene ring showed the highest catalytic activity of $4.9{\times}10^6$ g of PNBEs/$mol_{Ni}{\cdot}h$ and molecular weight of $15.28{\times}10^5$ g/mol with PDI < 2.30. Complexes with electron-withdrawing groups are more thermally stable (> 100 $^{\circ}C$), and tend to afford higher polymerization productivities than the ones having electron-donating groups. Amorphous polynorbornenes were obtained with good solubility in halogenated aromatic solvents. A vinyl addition mechanism has been proposed for the catalytic polymerization.