• Journal of Sensor Science and Technology
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• v.16 no.1
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• pp.11-16
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• 2007

CuO is an important transition metal oxide with many practical applications such as catalysts, p-type semiconductor, solar cells, magnetic storage media and cathode materials. In this contribution, nanocrystalline CuO powders were prepared by solution reduction method using copper chloride ($CuCl_{2}{\cdot}2H_{2}O$), hydrazine ($N_{2}H_{4}$) and NaOH and subsequent heat treatment. The gas sensor using nanocrystalline CuO powders showed high sensitivities to acetone and ethanol.

• 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.

• Proceedings of the KIEE Conference
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• 2006.05a
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• pp.57-59
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• 2006

In this study, we experimented a deterioration characteristics by series arcing with 600V polyvinyl chloride insulation wire and analyzed the glowing/growing process of copper oxide, waveforms of contact voltage, current, power dissipation and carbonized patterns of insulation. We know that how glowing contacts and surface arcing can decompose PVC insulation and that it is possible for the subsequent series arc to ignite, and burn insulation. We expect that these results are useful for advancing the state-of-the-art in fire protection by Providing a better understanding of how electrical fires can initiate.

• Textile Coloration and Finishing
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• v.12 no.2
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• pp.129-137
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• 2000

Silk fabrics were dyed by Cochineal extracts after mordanted with various mordants and their properties of dyeing, fastness and change of surface color were investigated. Silk fabrics were mordanted with aluminum potassium sulfate, copper acetate, tin chloride, iron sulfate or chromium potassium sulfate at $60^\circ{C}$ for 30 minutes and subsequently dyed at $60^\circ{C}$ for 60 minutes unless mentioned otherwise. The dye-uptake of silk fabrics increased with the concentration of Cochineal extracts and mordants used. Maximum dye-uptake was obtained at pH 3.5-4, regardless of the type of mordants used. Surface color of silk fabrics changed from red purple to purple when mordanted with Al or Cu mordant, from purple to purple blue with Fe mordant and showed red purple with Sn or Cr mordant, respectively. It also changed according to pH of dyeing bath. Dyed silk fabrics showed poor light fastness but good dry-cleaning, perspiration and rubbing fastness.

• Journal of the Korean Electrochemical Society
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• v.10 no.3
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• pp.175-178
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• 2007

Pure iron, Fe-0.4, and 1.2 wt.%Cu alloys were examined by conducting the electrochemical techniques in the weakly alkaline solution, pH9, controlled by $Ca(OH)_2$, solution added with 0.02M NaCl. The $R_P$ measured from ac impedance, selected 10 kHz and 10mHz, in weakly alkaline solutions containing chloride ions indicated that the addition of copper up to 1.2wt.% into the pure iron significantly improved the pitting resistance of iron. In contrast to alloy, the pure iron showed the rapid pitting occurrences in drying period. During the drying period, the corrosion potential of pure iron was shifted to less noble value, pitting initiation.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.1002-1008
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• 1999

Essential metabolic functions have been identified for seven macrominerals (calcirum, phosprorus, magnesium, sodium, potassium, chloride, and sulfur), and eight microminerals (cobalt, copper, iodine, iron, manganese, molybdenum, selenium, and zinc). Major functions for each of these minerals are summarized. Considerable research suggests that chromium is also essential and that it functions by facilitating insulin activity. Studies are reviewed which indicate that chromium supplementation of animal diets may: 1) increase glucose removal from blood, 2) reduce carcass fat and increase lean in nonruminants, 3) alter egg cholesterol content, and 4) enhance immunity and disease resistance in ruminants. A number of other minerals including nickel, boron, vanadium, arsenic, silicon, lithum, and lead have been reported to be essential, but specific metabolic functions have not been defined for any of these elements. Limited research in poultry suggests that boron may be of practical significance in some instances.

• Journal of the Korean Chemical Society
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• v.15 no.4
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• pp.183-189
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• 1971

Stoichiometry of hydrazine-bromate reaction has been studied in acid media of varying compositions, elucidating the effects of bromide and chloride ions in sulfuric acid, perchloric acid, hydrochloric acid, and hydrobromic acid at varying concentrations of hydrogen ion and cupric ion. The study shows that the number of red-ox equivalent consumed by one mole of hydrazine becomes practically 4.00 if the concentrations of bromide and hydrogen ions are kept higher than 0.1M and 6M, respectively. The presence of copper tends to reduce the bromate consumption by hydrazine in an irregular manner, but such an effect becomes unimportant if the concentrations of bromide and hydrogen ions are kept sufficiently high.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1493-1499
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• 2001

This paper investigated the dyeabiltiy and surface color of Han Jee dyed with Gardenia extract after mordanted with mordants under the various dyeing conditions. The results obtained were as follows 1) λmax of the dyeing Han Jee dyed with Gardenia appeared at 660 and 710nm. 2)K/s value of dyeing Han Jee was increased when dyeing condition, temperature, time was higher. 3) Surface color of Han Jee with mordants changed differently according to the mordants used : 3.2Y by Aluminum acetate, 2.0GY by Copper sulfate, 9.5YR by Iron sulfate. 3.4Y by Tin chloride, and 4.5Y by non-mordanting.

• Textile Coloration and Finishing
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• v.35 no.1
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• pp.1-7
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• 2023

In this study, the influence of pre-treatment(bleaching, mercerization by liquid ammonia and caustic soda) on cotton fabrics were investigated on dyeing Rubia cordifolia extracts. Aluminium Sulfate, Iron(Ⅱ) Sulfate Heptahydrate, Copper(Ⅱ) Sulfate Pentahydrate, Tin(Ⅱ) Sulfate, Manganese(Ⅱ) Chloride Tetrahydrate were used as mordanting agents. K/S value and washing fastnesses of the dyed cotton fabrics pretreated under different conditions were investigated. The K/S values were increased in the order of bleaching, liquid ammonia and mercerization pre-treatment. It was found that the pre-treatment conditions did not significantly affect the color change. The colorfastness to washing of most of all dyed fabrics were over grade 4 regardless of pre-treatment condition.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.737-741
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• 2005

In this study, the effect of copper content on the NO removal efficiency by Cu/MCM-41 has been investigated. MCM-41 was prepared by hydrothermal synthesis using a gel mixture of colloidal silica solution and cetyltrimethylammonium. Cu/MCM-41 was manufactured with copper content (5, 10, 20, and 40%) in Cu(II) acetylacetonate. The surface properties of MCM-41 were investigated by using pH, XRD, and FT-IR analyses. $N_2/77K$ adsorption isotherm characteristics, including the specific surface area and micropore volume were studied by BET's equation and Boer's t-plot methods. NO removal efficiency was confirmed by gas chromatography technique. From the experimental results, the MCM-41 was analyzed to have the surface functional groups of Si-OH and Si-O-Si and the characteristic diffraction lines (100), (110), (200), and (210) corresponding to a hexagonal arrangement structure. The copper content supported on MCM-41 appeared to increase the NO removal efficiency in spite of decreasing the specific surface areas or micropore volumes. Consequently, it was found that the copper content in Cu/MCM-41 played an important role in improving the NO removal efficiency, which was mainly attributed to the catalytic reactions.