• Journal of Environmental Health Sciences
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• v.50 no.3
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• pp.201-211
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• 2024

Background: Organic ultraviolet (UV) filters are widely used in sunscreen products and have been identified as an emerging contaminant. Organic UV filters co-exist with multiple components, but their mixture toxicity remains largely unknown. Objectives: We investigated the toxicity of single and binary mixtures of commonly used UV-filters using the human adrenocarcinoma (H295R) cell line. Methods: After exposure to non-cytotoxic concentrations of avobenzone (AVO), homosalate (HS), octisalate (OS), octinoxate (OMC), and octocrylene (OC), the levels of testosterone (T) and 17β-estradiol (E2) were measured. The median effective concentration (EC₅₀) values for the E2 of the individual substances were used to determine the mixture effect of four binary combinations: OMC+AVB, OMC+HS, OMC+OS, and OMC+OC. The synergistic, additive, and antagonistic effects of the mixture were determined by calculating toxic units (TU). To examine the mechanism of mixture toxicity, eight genes involved in steroidogenesis were analyzed using the real-time polymerase chain reaction. Results: The significant increase in E2 in H295R cells exposed to AVO, HS, OS, OMC, and OC suggest an estrogenic effect of the tested UV-filters. A significant decrease in T was observed in cells exposed to HS and OS. EC₅₀ values for E2 increase were 105 nM for AVO, 110 nM for HS, 120 nM for OS, 55 nM for OMC, and 80 nM for OC. Both binary mixtures consisting of OMC+HS and OMC+OS have synergistic effects. Conclusions: Our results showed that five types of UV-filter substances increase E2 in H295R cells. We examined the mixture toxicity in terms of increased estrogenicity and confirmed that E2 significantly increased when OMC was mixed with a salicylate-based UV-filters. These findings highlight the importance of determining the impact of UV filter mixtures.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.77-84
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• 1976

The preservation efficiency, quality and utilization of silage from 3 species of pumpkins (Mammoth pumpkin, Queensland blue pumpkin, Korean pumpkin) without and with 10, and 20% wheat bran additive were studied in this experiment. Silages were analysised and tested the chemical composition, pH and quality of silages between at 40-60 days and egg performance were carried out with mammoth pumpkin silage without additive. The results were summaried as follows. 1. The losses of all silage ware lower and similar as about 15% at 6 monthes following after silage-making but all raw pumpkins were spoilaged during the winter storaging. 2. The moisture content of silages were higher as about 97% in mammoth pumpkin silage, 94% in Queensland pumpkin silage and 91% in Korean pumpkin silage without additive and all nutrient content of silage without and with additive were depended on its content of raw silage material of pumpkins and wheat bran. The contents of moisture and N-free extract were slightly decrease but not significantly difference during the silaging and other contents were not so much changed. 3. Good quality of silage were made from all pumpkins with and without additive. Organic acid contents were 2.09-2.93% of lactic acid, 0.68-1.71% of acetic acid and 0% of butyric acid and it was pH 3.8-4.0 in silages. 4. Feed intakes, egg production and quality of egg were showed good result in 5.0 and 7.5% silage feeding group as D.M. base for egg performance. (P<0.01) 5. It was concluded that good quality of silage were made from pumpkins with and without wheat bran additive and it was suggested that poor quality feedstuff may be improved it feeding value by extended palatability with pumpkin additive silage.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.139-140
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• 2002

This paper discusses the effect of plating condition on the mechanical property of electroplated Cu film. Current density, the amount of the organic additives was found to affect the residual stress of electroplated copper film. The result show that, in the case of residual stress, the copper film deposited at higher additive result in lower residual stress and plating current by $15mA/cm^2$ induced a better result than any other ones.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.423-426
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• 2012

$Al_2O_3$/NiO powder was obtained through hydrolysis-condensation reactions and thermal treatments. An organic additive, triblock copolymer surfactant P123, was added to the starting materials to control the surface area and morphology. The synthesized powder was characterized by X-ray diffractometry (XRD), field-emission scanning electron microscopy (FE-SEM) and a Brunner-Emmett-Teller surface analysis (BET). The heterogeneous catalytic activity of this powder was applied to an epoxidation reaction of styrene and was monitored using a gas chromatograph with mass spectrophotometry (GC/MS).

• International Journal of Concrete Structures and Materials
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• v.3 no.2
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• pp.97-101
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• 2009

It has been known that acid-resistant concretes on the liquid glass basis have high porosity (up to 18${\sim}$20%), low strength and insufficient water resistance. Therefore they can not be used as materials for load-bearing structural elements. Significant increasing of silicate matrix strength and density was carried out by incorporation of special liquid organic alkali-soluble silicate additives, which block of superficial pores and reduces concrete shrinkage deformation. It was demonstrated that introduction of tetrafurfuryloxisilane additive sharply increases strength, durability and shock resistance of silicate polymer concrete in aggressive media. This effect is attributable to hardening of contacts between silicate binder gel globes and modification of alkaline component owing to "inoculation" of the furan radical. The optimal concrete composition with the increased strength, chemical resistance in the aggressive environments, density and crack resistance was obtained.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.2
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• pp.1-7
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• 2008

The trend of using more hardwood and recycled fibers, and closing more tightly of the paper mill white water system has resulted in build-up of fines as well as organic and inorganic contaminants in the white water. This changes in papermaking wet end requires developing chemical additive system that provides good fiber retention and drainage in closed white water system. In this study the effect of charge densities and chemical characteristics of microparticle systems consisted of cationic guar gums and anionic colloidal silica sols on drainage and retention have been examined. Results showed that higher charge density of cationic guar gum and anionic colloidal silica sol gave better retention and drainage. Particularly highly structured silica gave greater retention efficiency.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.392.1-392.1
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• 2014

Isoindigo based small molecules have attracted much attention in the field of optoelectronic devices due to their broad absorbance and high charge carrier mobilitiies. Herein, we investigate the field effect transistor characteristics of a series of isoindigo based donor-acceptor-donor (D-A-D) small molecules containing a variable number of thiophene moieties (named IDT, ID2T, and ID3T) which form pi-bridges between the D and A moieites and a different donor moiety (IDED). In order to improve the carrier mobility, 1-chloronaphthalene (CN) and 1,8-diiodooctane (DIO) as solvent additives were used. The film morphology, crystallinity and optical properties of the materials processed with various concentrations of solvent additives were investigated through atomic force microscopy (AFM), X-ray diffraction (XRD) and UV-vis absorption spectroscopy.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.655-657
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• 2002

The carbon nanotube emitters for field emission displays were fabricated by screen printing techniques. The pastes for screen printing are composed of organic binders, carbon nanotubes, and some additive materials. Then the pastes were printed on Cr-coated/Ag-printed soda-lime glass substrates. From the I-V characteristics, the turn-on field of SWNT was lower than that of MWNT. The decrease in the mesh size of screen masks resulted in decreasing the turn-on field and increasing the electron emission current. When the carbon nanotubes were mixed with glass frit, glass frit appeared to contribute to the vertically aligning of carbon nanotubes on glass.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.1-7
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• 2008

Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.274-278
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• 2002

The purpose of this study was to characterize the reaction of Cu surface with Cu slurry and CMP performance as a function of additives in CMP slurry. The polish rate of Cu was dependent on the kind of organic acids added in slurry. It was considered that polish rate of Cu was dependent on the concentration of carboxylates and mean particle size. When the etchant and oxidant were added in slurry, the highest removal rate and lower etch rate were measured at neutral pH. The addition of etchant, oxidant and pH adjustor played key roles of CMP ability in slurry. As the pH increased, polish rate of Cu was increased by the enhanced the mechanical effects due to effective dispersion of slurry particles. Alumina abrasives was more desirable for 1st step slurry because of high removal rate of Cu and high selectivity ratio among TaN and Cu.