• Progress in Superconductivity
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• v.5 no.1
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• pp.80-83
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• 2003

Superconducting YBCO thin films are fabricated on single-crystalline substrates by Metallo-organic Depostion process employing Trifluoroacetic acid as a chelating agent (MOD-TFA). (100)-oriented single crystalline LaAlO$_3$ substrates were employed to grow superconducting film with high crystallinity. The fully processed YBCO thin films were characterized with XRD, SEM, EDS, etc. The microstructures of YBCO thin films show labyrinth-like patterns. The origin of this microstructure was delineated by compositional inhomogeneity during the MOD process and it was shown that the microstructure may be modified by additives. In this work, effects of additives on the microstructures and electrical properties of YBCO thin films have been investigated.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.405-410
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• 2001

Bioremediation is a degradation process of existing organic contaminants in soils and groundwater by indigenous or inoculated microorganisms. This process can provide economical solution as well as safe and effective alternative in remediation technologies. However, it has been suggested that the rate of bioremediation process of organic contaminants by microorganisms can be limited by the concentration of nutrients and TEAs(Terminal Electron Accepters). In in-situ bioremediation, conventional pumping techniques have been used for supplying these additives. However, the injection of these additives is difficult in low permeable soils, and also hindered by preferential flow paths resulting from heterogeneities in high permeable ground. Therefore, the Injection of chemical additives is the most significant concern in in-situ bioremediation. Most recently, electrokinetic technique has been applied into the bioremediation and the injection characteristics under electrokinetics have not been examined in various soil types. Therefore, in this study, electrokinetic injection method is investigated in kaolinite and sand, and the concentration of ammonium(nutrients) and sulfate(TEAs) in soil is presented.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.486-491
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• 2014

We have been fabricated Thin-walled carbon nanotubes (TWNTs)/amine epoxy additives composite using Eco-friendly solvent system such as supercritical process and dry mixed process. TWNTs/amine epoxy additives composite has used as a curing agent for urethane based bisphenol A type epoxy resin. The thermo-mechanical property of the epoxy resin cured by TWNTs/amine epoxy additives composite is characterized by dynamic mechanical analysis(DMA) and dispersability of the nanotubes in the epoxy matrix is also confirmed by scanning electron microscope(SEM). As a results, the epoxy resin cured by TWNTs/amine epoxy additives composite with supercritical process shows enhanced dispersability of the TWNTs in the matrix and thermo-mechanical property when compare to dry mixed process.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.723-733
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• 2016

Intensive researches have been focused on the 3-dimensional packaging technology using through silicon via (TSV) to overcome the limitation in Cu interconnection scaling. Void-free filling of TSV by the Cu electrodeposition is required for the fabrication of reliable electronic devices. It is generally known that sufficient inhibition on the top and the sidewall of TSV, accompanying the selective Cu deposition on the bottom, enables the void-free bottom-up filling. Organic additives contained in the electrolyte locally determine the deposition rate of Cu inside the TSV. Investigation on the additive chemistry is essential for understanding the filling mechanisms of TSV based on the effects of additives in the Cu electrodeposition process. In this review, we introduce various filling mechanisms suggested by analyzing the additives effect, research on the three-additive system containing new levelers synthesized to increase efficiency of the filling process, and methods to improve the filling performance by modifying the functional groups of the additives or deposition mode.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.625-631
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• 1999

In this study, a series of test was conducted to show the characteristics of freezing -thawing process on soilcrete using the soft clay in a redevelopment paddy area, was treated with cement and several additives such as Beestar, CaSO4 , MgO, and polypropylene fiber, From the results of test, it was found that first addtivies -cement and beestar-was effective for compressive strength, and the resistance against freezing -thawing process was improved by secondary additives, in the order their effectiveness, i.e. CaSO4 , Synthetic fiber, MgO and Beestar.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.127-132
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• 1982

This experiment has been carried out for the purpose of investigating the effect of additives on densification and grain growth in magnesium oxide by a two-step process; hot pressing and heat treating. MgO powder has been obtained by calcining extra reagent grade MgCO3 at 90$0^{\circ}C$ for 30 minutes, and additives have been added to $MgCO_3$ in the form of soluble salts-Al$(NO_3)_3$$. $9H_2O$ and $Cr(NO_3)_3$.9H_2O$. The hot pressing has been carried out with changes of soaking time at 125$0^{\circ}C$ under the pressure of 250kg/$\textrm{cm}^2$, and the heat treating also at same temperature. The initial particle size of MgO measured by particle size analyzer was 0.86 microns. Densification rate obeyed the equation D=K lnt + C, and grain growth rate obeyed the equation G-G0=kt1/2. It was vaporization of some $Cr_2O_3$ and formation of solid solution that had an influence on desification of MgO containing $Cr_2O_3$. Activation energy for grain growth of pure MgO was 62.4 kcal/mole, therefore grain growth was supposed to be diffusioncontrolled process. But after heat treatmeat, excess additives were expected to slow down the grain growth by the formation of second phase or the solute atoms at grainboundary.

• Journal of Pharmaceutical Investigation
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• v.39 no.1
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• pp.43-49
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• 2009

Aspirin or acetylsalicylic acid, a member of the salicylate family, is frequently used as an analgesic, antipyretic, anti-inflammatory and antiplatelet drug. Because aspirin is chemically unstable in water and heat for tablet formulation, additives including lubricants are used in preparing aspirin tablets, using a dry-granulation process. Aspirin tablets are produced by a number of manufacturers which usually use their own unique combination of additives during the manufacturing process. In this study, we employed an NMR based metabolomics technique to identify the manufacturers of various aspirin tablets. Aspirin tablets from six different companies were analyzed by 1H 400 MHz NMR. The acquired data was then integrated and processed by principal component analysis (PCA). Based on the NMR data, we were able to identify peaks corresponding to acetylsalicylic acid in all of the six samples, whereas different NMR patterns were found in the aromatic and aliphatic regions depending on the unique additive used. These observations led to the conclusion that the differences in the NMR patterns among the different aspirin tablets were due to the presence of additives.

• Membrane and Water Treatment
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• v.7 no.4
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• pp.355-365
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• 2016

The improvement of fouling resistance of porous polymeric membrane is one of the most important targets in membrane preparation for water purification in many process like wastewater treatment. Membranes can be modified by various techniques, including the treatment of polymer material, blending of hydrophilic polymer into polymer solution, and post treatment of fabricated membrane. This research proposed the modifications of morphology and surface property of hydrophobic membrane by blending polyethersulfone (PES) with three polymeric additives, polyvinylpyrrolidone (PVP), Pluronic F127 (Plu), and Tetronic 1307 (Tet). PES hollow fiber membranes were fabricated via dry-wet spinning process by using a spinneret with inner and outer diameter of 0.7 and 1.0 mm, respectively. The morphology changes of PES blend membrane by those additives, as well as the change of performance in ultrafiltration module were comparatively observed. The surface structure of membranes was characterized by atomic force microscopy and Fourier transform infra red spectroscopy. The cross section morphology of PES blend hollow fiber membranes was investigated by scanning electron microscopy. The results showed that all polymeric additives blended in this system affected to improve the performances of PES membrane. The ultra-filtration experiment confirmed that PES-PVP membrane showed the best performance among the three membranes on the basis of filtration stability.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1583-1585
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• 2007

The purpose of this research is to control proper processing condition of RGB photo resistant in the ink-jet process increasing processing ability by adding additives. The viscosities of modified RGB photo resistant were $10{\sim}14cps$ and the additives could decreased agglomeration and flowing trace of photo resistant effectively. Another way, the adhesion between photo resistant and glass substrate was improved by modifying photo resistant and substrate. The surface tensions of modified photo resistant were same as that of original RGB photo resistant. The additives appeared a better compatibility with photo resistant, and the micelle of photo resistant did not be broken during modified process.

• Journal of the Korean Ceramic Society
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• v.34 no.3
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• pp.323-329
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• 1997

Particle growth of BT-oxalate was investigated in aging with various additives such as glycerine, chloro-form and NaCl. Their effects on size and morphlogy of particle was examined. It can be known that particle size distributions of BT-oxalate precipitate varied with amounts of these additivies. With small amounts of these additives, particle growth of nonuniform distribution was occurred, but above 1 mole percent of those additives, uniform size distributions of about 0.4 ${\mu}{\textrm}{m}$ could be obtain. There was little difference among the effects by the kinds of additives. From the decomposition of uniform BT-oxalate, BaTiO3 powders of about 0.3${\mu}{\textrm}{m}$ could be obtained.