• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1727-1734
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• 2013

Synthesis and characterization of some novel symmetric bis-azospiropyrans are reported in this study. These bis-azospiropyrans are bifunctional chromophores with two spiropyrans linked by a bis-azo extended aromatic system that produce more color strength (large molar absorption coefficient in mero forms) due to appending two azospiropyran chromophores on one molecule. Comparing to the molar absorption coefficients of the conventional spiropyran chromophores (${\varepsilon}=0.31{\times}10^4\;M^{-1}{\cdot}cm^{-1}$) and mono-azospiropyran chromophores ($1.35{\times}10^4\;M^{-1}{\cdot}cm^{-1}$), the novel synthesized photochromes showed astonishingly increased molar absorption coefficients ($2.3-3.8{\times}10^4\;M^{-1}{\cdot}cm^{-1}$) at the same conditions. Such high molar absorption coefficients confers high sensitivity to light and more color intensity of mero form, that leads to improvement of their light sensitivity and better discrimination of spiro (OFF) form from mero (ON) ones in molecular switches. The structures were deduced from their MS, FT-IR, and $^1H$-NMR spectroscopic data and CHN analysis. All the synthesized photochemically bifunctional compounds revealed fluorescent emission in their colorless form which was faded out after exposing to UV light. Fluorescence quantum yield values of the mero forms were 0.25-0.81 and two high fluorescence quantum yield values (0.60 and 0.81) were found in these series.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.1985-1989
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• 2013

A simple colorimetric and fluorescent anion sensor 1 based on salicylimine showed a high selectivity and sensitivity for detection of cyanide in aqueous solution. The receptor 1 showed high selectivity toward $CN^-$ ions in a 1:1 stoichiometric manner, which induces a fast color change from colorless to orange and a dramatic enhancement in fluorescence intensity selectively for cyanide anions over other anions. Such selectivity resulted from the nucleophilic addition of $CN^-$ to the carbon atom of an electron-deficient imine group. The sensitivity of the fluorescence-based assay (0.06 ${\mu}M$) is below the 1.9 ${\mu}M$ suggested by the World Health Organization (WHO) as the maximum allowable cyanide concentration in drinking water, capable of being a practical system for the monitoring of $CN^-$ concentrations in aqueous samples.

• 한국어류학회지
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• 제19권4호
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• pp.365-370
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• 2007

최근 우리나라의 남해 연안에서 출현하고 있는 가자미목 어류 2종을 조사한 결과 지금까지 국내에서 서식이 보고되지 않은 붕넙치과의 Psettina tosana와 넙치과의 Pseudorhombus oculocirris로 동정되었다. P. tosana는 형태적으로 P. gigantea와 P. iijimae와 비슷하나 P. tosana는 가슴지느러미 연조가 9~10이고, 측선린수가 적으며, snout 주변이 검지않아 P. gigantea와 다르고, 새궁의 상지에 새파가 없고, 하악의 치열이 1열인 점이 P. iijimae와는 구별되었다. 한편 P. oculocirris는 P. pentophthalmus에 비하여 측선비늘 수가 많고, 유안측의 전비공만 tubular 타입에 flap이 존재하고, 등지느러미 앞쪽의 유리된 연조가 약간 납작하고, 길다는 점이 특징적이다.

• 한국세라믹학회지
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• 제53권4호
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• pp.450-455
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• 2016

Color change in single-crystal, yellow, red, purple, and colorless cubic zirconias (CZs) was investigated as a function of annealing in vacuum and air atmosphere at $800-1400^{\circ}C$ for 30 min, for development of a damascene process of plugging a precious metal paste at the elevated temperature. Coloring-element contents of the CZs were evaluated using WD-XRF, and the color change determined visually by naked eye, and using a digital camera and UV-Vis-NIR color analyzer. WD-XRF showed that all of the CZs had cubic-phase stabilizer elements and coloring elements. All CZs that underwent vacuum annealing exhibited a slight color change at $<900^{\circ}C$, while their colors began to change to black at $1100^{\circ}C$, and became opaque black at $1400^{\circ}C$. After air annealing, there was almost no color change up to $1400^{\circ}C$. Since red and purple CZs showed greater color difference (CD) values than the others, the degree of CD is likely to depend on the original color of the CZ due to the different stabilities of their coloring elements during annealing. Based on our results, it is suggested that annealing in air at $<900^{\circ}C$ is advantageous, and assorted colored CZs can be used for precious metal damascene.

• 대한임상독성학회지
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• 제6권1호
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• pp.49-51
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• 2008

Sodium azide (NaN3) is a white to colorless, crystalline powder that is highly water soluble, tasteless, and odorless. It is used mainly as a preservative in aqueous laboratory reagents and biologic fluids and also as an automobile airbag gas generant. Although it has caused deaths for decades, the toxic properties and effects of sodium azide in humans remains unknown. A 31-year-old comatose female was transported to the emergency department with an empty bottle labeled sodium azide. She developed cardiac arrest 15 minutes after arrival and expired in spite of 30 minutes of resuscitative effort. Subsequently, resuscitation team members incidentally suffered from sodium azide's exposure and developed eye discomfort, skin rashes parasthesias, pruritus, sore throat, and headache.

• The Korean Journal of Ecology
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• 제6권4호
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• pp.21-28
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• 1983

The relationship of Paramecium bursaria with its symbiiotic Chlorella was studied in the view-point of photosynthesis and its product movement. The following results were obtained. In 1/10 dilution of bacterized medium green Paramecium grew and survived better than colorless Paramecium. P. bursaria was competitively related to its symbiotic algae as far as the change of total chlorophyll contents was concerned. Therefore, in continuous darkness total chlorophyll contents of green Paramecia decreased proportionally to the time course. Under the condition, on the other hand, that the bacterized medium was not replenished over 10 days, total chlorophyll contents in P. bursaria increased by over 2 times as much as those in normal condition. By means of Oxygen Diometer it was assured that green Paramecium was able to utilize thoitic the great part of oxygen evolved photosynthetically by its symbiotic algae. Also when was given many starch grains were found in symbiotic chlorella through electron micrography. These data suggested that P. bursaria was photosynthetically given lots of benifit by its symbiotic chlorella.

• 대한수의학회지
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• 제48권1호
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• pp.105-110
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• 2008

The purpose of this study is to define the normal findings of cerebrospinal fluid (CSF) of the clinically healthy Beagle dogs and to provide basic information in diagnosis of neurologic disorders. CSF obtained from 13 clinically healthy dogs was examined for total and differential cell counts, total protein concentration, glucose and lactate dehydrogenase (LDH) concentration, specific gravity, turbidity, and protein electrophoresis. On gross examination, CSF samples evaluated were clear and colorless. Few red blood cells and nucleated cells were present. The mean concentration of glucose and LDH examined were 65.8 mg/dl and 2.7 mg/dl, respectively. The cellular components of CSF samples based on differential counts were monocytes (41.9%), activated macrophages (35.8%), lymphocytes (20.0%), neutrophils (1.6%), and eosinophils (0.7%). The fractions of electrophoretic protein in CSF were albumin (52.7%), alpha-globulin (16.5%), beta-globulin (24.8%), and gamma-globulin (3.0%). Results of albumin quota were ranged from 0.15 to 0.38. In conclusion, this study provided normal composition of CSF in Beagle dogs.

• 대한임상독성학회지
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• 제2권2호
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• pp.147-150
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• 2004

Hydrogen sulfide is a colorless, and malodorous 'rotten eggs' gas that results from the decay of organic material. It is a byproduct of industry and agriculture. The mechanism of its toxicity is primarily related to inhibition of oxidative phosphorylation, which causes a decrease in available cellular energy. Because there is no rapid method of detection that is of clinical diagnostic use, management decisions must be made based on history, clinical presentation, and diagnostic tests that imply hydrogen sulfide's presence. Although there is some anecdotal evidence to suggest that the early use of hyperbaric oxygen is beneficial, supportive care remains the mainstay of therapy. We describe an occupational exposure to hydrogen sulfide gas in 51-year-old man. While cleaning the sewage of pigs. he became unconscious. When he arrived in the emergency department, he had irritability and confused mentality. The typical smell of rotten eggs on clothing and exhaled air were enough to be considered to be exposed to hydrogen sulfide. Hyperbaric oxygen therapy was performed. He had a recovery to normal function.

• 대한임상독성학회지
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• 제5권1호
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• pp.61-66
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• 2007

Trichloroethylene (TCE) is an unsaturated chlorinated hydrocarbon in the form of a colorless, volatile liquid, which is used as an industrial organic solvent for spot removal and for metal degreasing. In general, the primary complications of TCE poisoning result from involvement of the central nervous and respiratory systems, including aspiration pneumonia. A case is reported of a 54-year-old man who presented in a comatose state after accidental ingestion of 100 ml of TCE, and who recovered after conservative treatment and mechanical ventilation. We discuss this case and present a literature review.

• 한국안광학회지
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• 제3권1호
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• pp.237-242
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• 1998

$80SiO_2-20TiO_2$(mol%)의 무색투명한 비정질 박막을 현미경용 슬라이드 유리판과 사파이어 위에 tetraethyl orthosilicate와 titanium trichloride의 전구체 용액을 사용하여 스핀코팅방법으로 제조하였다. 코팅 후 $750^{\circ}C$에서 열처리된 박막은 높은 투과율과 낮은 반사율을 보였다. 슬라이드 유리판에 코팅한 $SiO_2-TiO_2$ 박막의 경우에 나트륨이온과 산소 간의 강한 상호작용에 의하여 고온과 높은 습도에서도 안정성이 우수하였다.