• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.218-221
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• 2006

The photovoltaic properties of CIES cells on alumina substrate were improved by using the Na-doped Mo as theabotom layer of hilo back contact. Na was supplied to the CIGS bulk region from alumina/Na-doped Mo/Mo/alumina? structure, as same assimilar to the Na diffusion from soda-lime glass. The content diffusion of Na from Na-doped bfo was smaller more controlled than that from SLG. These Our results indicate that Na-doped bfo act as Na source material and contents of Na amount can be controlled without the use of an alkali barrier layer. The best CIGS solar cell with conversion efficiency of 13.34%, $J_{sc}=34.62mA/cm^2,\;V_{oc}=0.58V$ and FF=66% for an active area of $0.45cm^2$ on the alumina substrate was obtained in the condition of for 100nm Na-doped Mo/1000nm Mo.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.823-828
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• 2002

Concrete used up to date semipermanent architecture material but now day concrete early deterioration emboss social issue because of construction structure and environmental factor. so, many study of deterioration concrete construction improve durability used impregnation alkalization agent. Impregnation alkalization agent deterioration concrete construction spray infiltration or diffusion improve alkali and filler inter minuteness void elaborateness constitution concrete. but many study of harding concrete change inter minuteness void that Is insufficiency also, To study of method recover shape impregnation alkalization agent apply deterioration concrete construction. impregnation alkalization agent infiltration according to test of porosity, premeameter, absorption.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.40-46
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• 1994

In order to study the properties of cochineal color, variation of uv, visible spectra by pH, dyeing properties on the silk in several dyeing conditions and thermodynamic parameter were investigated. Cochineal colors had an unusual to pH, especially had instability in alkali condition. An increase in the dyeing temperature and in time resulted in an increase in the dye content of silk fibers. Concentration of cochineal color in the silk fiber was related to pH and the maximum exhaustion of cochineal colors showed at about pH 3. The value of apparent diffusion coefficients and standard affinities of dyeing increased with the increase of dyeing temperature. The standard heats of dyeing(ΔH°), variation of entropy(ΔS°) and activation energy(E/sub act/) were caculated to be -1.72kcal/mo1, -3.77cal/mo1ㆍdeg and 1.26kcal/mo1, respectively. Silk fabrics were dyed bright red by tin chloride, reddish purple by copper sulfate, and bluish gray by iron sulfate, respectively. Lightfastness of silk fabrics mordanted by metal ion was weak.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.183-188
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• 1997

Antimicrobial activity of various extracts of Xanthium strumarium L. was tested against 25 strains of bacteria, yeast and fungus. The crude ethylacetate extract exhibited strong growth inhibition to the tested strains with the exception of partial Gram-negative bacteria. The property of antimicrobial compound was very stable under heat treatment at $120^{\circ}C$, but it was unstable in acid (pH 3.0) and alkali (pH 10.0) treatment. The antimicrobial compounds were purified by boiling water extraction, ethylacetate extraction, charcoal column chromatography, silica gel column chro- matography and reverse phase HPLC. The purified compound A and B were detected in a single peak (each above 98% purity) through the HPLC analysis. The compound A and B showed a strong growth inhibition against Gram-negative and positive bacteria in the agar diffusion method. When tested by the FDA method using the esterase, compound A mainly inhibited the growth of bacteria and compound B showed the growth inhibition of both bacteria and yeasts.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.53-53
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• 2002

Alkali-soluble random copolymer (ASR) was used as a functional resin in the emulsion polymerization of styrene to prepare structured nanoparticles. The calorimetric technique was applied to study the kinetics of emulsion polymerization of styrene using ASR and conventional ionic emulsifier, sodium dodecyl benzene sulfonate (SDBS). ASR could form aggregates like micelles and the solubilization ability of the aggregates was dependent on the neutralization degree of ASR. The rate of polymerization in ASR system was lower than that in SDBS system. This result can be explained by the creation of a hairy ASR layer around the particle surface, which decreases the diffusion rate of free radicals through this region. Although a decrease in particle size was observed, the rate of polymerization decreased with increasing ASR concentration. The higher the concentration of ASR is, the thicker and denser ASR layer may be, and the more difficult it would therefore be for radicals to reach the particle through this layer of ASR. The rate of polymerization decreased with increasing the neutralization degree of ASR. The aggregates with high neutralization of ASR are less efficient in solubilizing the monomer and capturing initiator radicals than that of the lower neutralization degree, which leads to decrease in rate of polymerization.

• Journal of Pharmaceutical Investigation
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• v.1 no.1
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• pp.101-108
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• 1971

The stability and toxicity test for p.p'-DDT, DDVP and dipterex that put to used sample in this study effects is follows A. about p.p'-DDT (1) In elevating the stability of p.p'-DDT, best stabilizing solvent was benzene. (2) The stability-agent has no difficulty as long as it not contain metal ion for instance $Z_n^{2+}$,$C_r^{3+}$,$Al^{3+}$,and $Fe^{2+or3+}$ but in case of contain $F_e^{3+}$, the combination of salicylaminoguanidine is best effective. (3) Using this product for water-suspension, We must use span 40 for stability agent and adding it at the same time. (4) We must use container which does not week alkali and metal ion but it is to preserved in tight light-resistant container. (5) The stopper of container is adapted with above-mentioned condition of container, but it is better not to use metal material. (6) This product needs opening ventilation more than 30 minutes after diffusion or spray and in the room we remove cause of remained poison by cleaning the bottom. B. about DDVP and Dipterex (1) Benzene or toluene in best solvent to preserve stability of DDVP and Dipterex. (2) Span 40 is superior for stability agent of this product and second is span 80. (3) The pH of solution is very stable in pH 5-6 and comparative stable in alkali more than p,p'-DDT. (4) Container is to preserved in tight, lightresistant container and especially be careful of outflow and inflow of water. (5) Because this product is centeral stimulant poison, we must pay attention to prevent cause of contact diadermic toxicity after use.

• Polymer(Korea)
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• v.24 no.6
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• pp.802-809
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• 2000

Counterion-specific helix formation and ion-selective transport of alkali metal chlorides (LiCl, NaCl, KCl, CsCl) were investigated for a poly(L-glutamic acid)(PLGA)/poly (vinyl alcohol)(PVA) blend membrane immersed in aqueous ethanol. The counterion specificity for helix formation of PLG alkali metal salts in the membrane was Li>Na>K>Cs. This specificity is ascribed to a contact ion-pair formation between the PLG carboxyl anion and the bound counterion, which depends on the energy balance between the electrostatic interaction and the desolvation. In aqueous ethanol, an appreciable ion-selectivity was observed for the permeability coefficient, i.e. Li$^{+}{\cdot}$Cl$^{-}$) formation between counterion and coion, and the latter to a specific interaction of diffusing counterions with polymer charges.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.535-539
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• 2006

Effects of alkaline additives on the $CO_2$ removal reaction have been investigated by a thermogravimetric analyzer. $Li_2ZrO_3$ was synthesized by soild reaction of $ZrO_2$ with $Li_2CO_3$ and then alkali chemicals were added to the synthesized $Li_2ZrO_3$ and then heat treatment was carried out. Addition of alkali chemicals enhanced the reactivity of $Li_2ZrO_3$ with the following order; $K_2CO_3>NaCl>LiCl>Na_2CO_3$, which were resulted from the formation of partially melted $Li_2CO_3$. SEM photographs showed the presence of melted state and the XRD results showed that the chemical states of added salts were not changed. Addition of NaCl caused the induction time of about 60 min at the initial reaction stage and the addition of $Na_2CO_3$ inhibited the decomposition of $Li_2CO_3$ at about $700{\sim}750^{\circ}C$.

• Journal of the Korea Concrete Institute
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• v.16 no.4 s.82
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• pp.549-555
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• 2004

Cement of three alkalinities (equivalent alkalinities of 0.36,0.52 and 0.97) was employed in fabricating a set of classical G109 type specimens. To-date, these have been subjected to a one week wet-one week dry cyclic pending using 15 w/o NaCl solution. At the end of the dry period, potential and macro-cell current were measured to indicate whether the top reinforcing steel was in the passive or active state. Once this bar became active, the specimen was autopsied and the extent of corrosion was documented. Subsequent to visual inspection, concrete powder samples were collected from the upper region of the top rebar trace; and at a certain times concrete cores were taken from non-reinforced specimens. Using these, determinations were made of (1) critical chloride concentration for corrosion initiation ($Cl_{th}^-$), (2) effective chloride diffusion coefficient ($D_e$), and (3) pore water alkalinity ($[OH^-]$). The pore water alkalinity was strongly related to the alkali content of cement that was used in the mix. The chloride concentration, ($Cl^-$), was greater at active than at passive sites, presumably as a consequence of electro migration and accumulation of these species at active site subsequent to corrosion initiation. Accordingly, ($Cl^-$) at passive sites was considered indicative of the threshold concentration fur corrosion initiation. The $Cl_{th}^-$ was increased with increasing Time-to-corrosion ($T_i$). Consequently, the HA(High Alkalinity) specimens exhibited the highest $Cl_{th}^-$ and the NA(Normal Alkalinity) was the least. This range exceeds what has previously been reported in North America. In addition, the effective diffusion coefficient, $D_e$, was about 40 percent lower for concrete prepared with the HA cement compared to the NA and LA(Low Alkalinity) ones.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.35-44
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• 2008

Long-term degradation of coment barrier by diffusion was studied with reactive transport modeling. The result of modeling showed that cement barrier was altered about 30cm thickness after 50,000 years. The pH decreased from 13.0 to 11.9 because of depletion of alkali ions, and dissolution/precipitation of portlandite and CSH (Calcium Silicate Hydrate). In addition, porosity increased about 0.3 because of dissolution of portlandite and $CSH2.0(Ca_2SiO_3(OH)_2:0.17H_2O)$. The solubility of uranium also increased with the increase of pe value The results of this study indicate that long-term degradation of comet can enhance the transport of nuclide by changing pH, pe, porosity in barrier.