• 한국신재생에너지학회:학술대회논문집
• /
• 2006.06a
• /
• pp.222-224
• /
• 2006

A non-vacuum process for $Cu(In,Ga)Se_2$ (CIGS) thin film solar cells from nanoparticle precursors was described in this work CIGS nanoparticle precursors was prepared by a low temperature colloidal route by reacting the starting materials $(CuI,\;InI_3,\;GaI_3\;and\;Na_2Se)$ in organic solvents, by which fine CIGS nanoparticles of about 20nm in diameter were obtained. The nanoparticle precursors were mixed with organic binder material for the rheology of the mixture to be adjusted for the doctor blade method. After depositing the mixture of CIGS with binder on Mo/glass substrate, the samples were preheated on the hot plate in air to evaporate remaining solvents ud to burn the organic binder material. Subsequently, the resultant (porous) CIGS/Mo/glass simple was selenized in a two-zone Rapid Thermal Process (RTP) furnace in order to get a solar ceil applicable dense CIGS absorber layer. Complete solar cell structure was obtained by depositing. The other layers including CdS buffer layer, ZnO window layer and Al electrodes by conventional methods. The resultant solar cell showed a conversion efficiency of 0.5%.

• Journal of Pharmaceutical Investigation
• /
• v.10 no.3
• /
• pp.14-19
• /
• 1980

The dissociation constant of erythrosine in the mixed solvent systems of water-alcohols and water-acetone at various pH and in concentration media were determined by spectrophotometric method. Methanol, ethanol, and acetone were employed as solvents and studied the changes of pK values of erythrosine according to the kind and change of concentration of organic solvent which is mixed into water solution. The effect of organic solvent on pK is negligible at 40% while in the case of above 40% mixing, it is not negligible.

• Annals of Occupational and Environmental Medicine
• /
• v.35
• /
• pp.11.1-11.17
• /
• 2023

Background: Studies on the relationship between organic solvent exposure and chronic kidney disease (CKD) have presented inconsistent results. Definition of CKD has changed in 2012, and other cohort studies have been newly published. Therefore, this study aimed to newly confirm the relationship between organic solvent exposure and CKD through an updated meta-analysis including additional studies. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search was conducted on January 2, 2023 using Embase and MEDLINE databases. Case-control and cohort studies on the relationship between organic solvent exposure and CKD were included. Two authors independently reviewed full-text. Results: Of 5,109 studies identified, a total of 19 studies (control studies: 14 and cohort studies: 5) were finally included in our meta-analysis. The pooled risk of CKD in the organic solvent exposed group was 2.44 (1.72-3.47). The risk of a low-level exposure group was 1.07 (0.77-1.49). The total risk of a high-level exposure group was 2.44 (1.19-5.00). The risk of glomerulonephritis was 2.69 (1.18-6.11). The risk was 1.46 (1.29-1.64) for worsening of renal function. The pooled risk was 2.41 (1.57-3.70) in case-control studies and 2.51 (1.34-4.70) in cohort studies. The risk of subgroup classified as 'good' by the Newcastle Ottawa scale score was 1.93 (1.43-2.61). Conclusions: This study confirmed that the risk of CKD was significantly increased in workers exposed to mixed organic solvents. Further research is needed to determine the exact mechanisms and thresholds. Surveillance for kidney damage in the group exposed to high levels of organic solvents should be conducted.

• Polymer(Korea)
• /
• v.35 no.5
• /
• pp.458-466
• /
• 2011

In the mixed system of supercritical carbon dioxide/organic solvents, poly(vinyl alcohol)(PVA) film of high degree of hydrolysis could be dyed with a dichroic dye of C. I. direct black 22(DB22) and as a result, high durability was obtained. Especially, as a dye dispersant in a supercritical fluid phase, a mixed solvent system of ethylene glycol: dimethyl sulfoxide=4 : 6 weight ratio was investigated. Then the optimum pressure for dyeing could be reduced down to 200 bar. Using this supercritical fluid system, the maximum dyeing appeared as the transmittance of less than 1% and the waste amount was reduced to the level of 1/10. After 500% drawing of this PVA film, both the polarizing efficiency of 94% and the single piece transmittance of 30% were obtained. The limitation of DB22 and further improvements were also discussed.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.3 no.2
• /
• pp.177-187
• /
• 1993

The exposure levels of mixed organic solvents for 66 exposed workers in six paint manufacturing plants were evaluated. In 66 exposed workers and 30 control subjects, we also determined the concentrations of toluene and xylene metabolites, hippuric acid, ($o^-$, $m^-$, and $p^-$)methylhippuric acid. The results were as follow ; 1. Seven organic compounds, which on averge accounted for approximately 90% of the identified mass in each painting plants air samples, were selected for quantification : methyl ethyl ketone, ethyl acetate, methyl isobutyl ketone, toluene, butyl acetate, ethyl benzene, ($o^-$, $m^-$, $p^-$)xylene. 2. The average mixed organic solvent exposure levels in 66 points with workplce were 3.8ppm of MEK, 12.2ppm of ethyl acetate, 4.0ppm of MIBK, 28.7ppm of toluene, 3.8ppm of butyl acetate, 10.2ppm of ethyl benzene, 14.6ppm of xylene, respectively. 3. For the total 66 points with workplace, the rate of them of which mixed solvents in air was exceeded th TLV of 1.0 were obtained for 23%(15/66 point). 4. The concentrations of hippuric acid in urine of exposed group and control were $0.94{\pm}0.65g/g$ of creatinine, $0.16{\pm}0.11g/g$ of creatinine, respectively. 5. There was a linear correlation between the end shift hippuric acid acid levels in urine and exposed toluene in air : y=0.02079X+494.2, r=0.6488, n=55 y:hippuric acid in urine(mg/g of creatinine), x:toluene levels in air(ppb) Toluene levels of 100ppm in air have been caculated to hippuric acid of 2.57g/g of creatinine in urine. 6. There was a linear correlation between the end shift methylhippuric acid acid levels in urine and exposed xylene in air : y=0.01664X+31.6, r=0.7264, n=55 y:methylhippuric acid in urine(mg/g of crea.), x:xylene levels in air(ppb) Xylene levels of 100ppm in air have been caculated to methylhippuric acid of 1.69g/g of creatinine in urine.

• 대한예방의학회:학술대회논문집
• /
• 2005.10a
• /
• pp.386-386
• /
• 2005

• Journal of the Korean Chemical Society
• /
• v.30 no.4
• /
• pp.377-382
• /
• 1986

Racemic tris-oxalatocobaltate (III) complex ions were optically resolved by an optical active complex, ${\Delta}$-tris-ethylenediamine cobalt (III), and then racemization of ${\bigwedge}-[Co(ox)_3]^{3-}$ obtained was investigated in various mixed solvent such as water-organic solvent (organic solvents=ethanol, iso-propyl alcohol, acetone, and dioxane). The rate of racemization was increased with following order; water < ethanol < acetone < isopropyl alcohol < dioxane; which is the same order for polarizability of organic solvent added. Considering ${\Delta}H^{\neq},\;{\Delta}S^{\neq}$ and above facts for the racemization of ${\bigwedge}-[Co(ox)_3]^{3-}$, it seems to be twist mechanism of plausible mechanisms.

• Journal of Applied Biological Chemistry
• /
• v.57 no.3
• /
• pp.197-203
• /
• 2014

Various parameters such as solvent selection, concentration, solid/liquid ratio, soaking time, temperature, stationary, shaking conditions, and repeated extractions were investigated in order to determine the optimum extraction conditions of ${\beta}$-glucosidase from bagasse fermented by mixed culture of Aspergillus niger NRC 7A and Aspergillus oryzae NRRL 447. Among various solvents tested, non ionic detergents gave the best results than the inorganic or organic salt solutions and distilled water. The optimum conditions for extraction of ${\beta}$-glucosidase were 30 min soaking time at $40^{\circ}C$ under shaking condition at 150 rpm, with solid/liquid ratio 1:15 (w/v), which yielded $2882.74{\pm}95.52U/g$ fermented culture (g fc) of enzyme activity. With repeated washes under the above optimum conditions, the results showed that enzyme extracted in the $1^{st}$ and $2^{nd}$ washes represents about 90% of the total activity.

• Bulletin of the Korean Chemical Society
• /
• v.1 no.3
• /
• pp.101-104
• /
• 1980

A sequential copolypeptide with repeating unit sequences, in which a glycyl residue is flanked progressively by two ${\gamma}$-benzyl-L-glutamyl residues, has been synthesized by poymerizing p-nitrophenyl ester of ${\gamma}$-benzyl-L-glutamyl-${\gamma}$ -benzyl-L-gutamyl-glycine. Polymers obtained were characterized by viscosity and infra-red spectral data. The highest molecular weight obtained was 21,000. Molecular conformation in solid state was found to be a mixed form of and |${\beta}$-structure. Polymers obtained were insoluble in the most of the organic solvents except in a strong acid like dichloroacetic acid, but in binary mixtures of solvents such as dichloroacetic acid-ethylene dichloride or dichloroacetic acid-chloroform, they were soluble within certain ranges of solvent compositions.

• YAKHAK HOEJI
• /
• v.19 no.1
• /
• pp.30-35
• /
• 1975

pKi values and sensitivity of acid-base indicators in the mixed solvent systems of water-alcohols and water-acetone at differential pH and in concentration media were determined by spectrophotometric method. When the concentration of the organic solvents were increased, the pKi values of sulfophthalein indicators, thymol blue and bromcresol purple, became larger whereas those of an axo indicator, methyl yellow, became smaller nad the pH values of the equivalent points of acids became smaller and the pH values of the equivalent points of acids became higher than those in the aqueous solution. potassium bicarbonate, a standard compound used in the organic solvent systems without a prerequisite procedure of expelling carbon dioxide by boiling.