• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.375-382
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• 2017

In the present review, we provide an overview of the research trend of anodic $TiO_2$ nanostructures. To date, most anodic $TiO_2$ nanostructure formation has focused on the fluoride ion electrolyte system to form nanotube layers. Recently, a novel approach that describes the formation of thick, self-organized $TiO_2$ nanostructures was reported. These layers can be prepared on Ti metal by anodization in a hot organic/$K_2HPO_4$ electrolyte. This nanostructure consists of a strongly interlinked network of nanosized $TiO_2$, and thus provides a considerably higher specific surface area than that of using anodic $TiO_2$ nanotubes. This review describes the formation mechanism and novel properties of the new nanostructures, and introduces potential applications.

• Journal of Chest Surgery
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• v.10 no.2
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• pp.299-314
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• 1977

Clinical experience on 16 cases of open heart surgery under the extracorporeal circulation with mild or moderate hypothermia and partial hemodilution technique at the National Medical Center during the period from June 1976 to October 1977. Nine of sixteen were congenital heart disease and seven were acquired heart disease. The age of the patient ranged between 6 and 48 years. The body weight varied from 18.5kg to 60kg and body surface area 0. 79-1.70m2. The average priming volume of pump oxygenator was 2080 ml, which was consisted fresh ACD blood, buffered Hartmann`s solution, Mannitol, 50% dextrose in water and Vit. C. The average hemodilution rate was 27%. The average flow 2.3 L/min/m2 or 80 ml/min and the duration of perfusion varied from 31 min to 270 min with average of 107 min. The perfusion was carried out under the mild or moderate hypothermia using core cooling alone in 10 cases, core cooling and local myocardial cooling with $0-4^{\circ}C$ physiologic saline in 2 cases. From a hemodynamic point of view, the blood pressure dropped down around 80 mmHg after the initiation of perfusion follwed by increase to safety level and stable during the perfusion. The central venous pressure remained within normal limits. In most cases, hemoglobin and hematocrit decreased during and after the perfusion. Hemogiobin level was decreased, average of 20.6 %, hematocrit 18.6%, pletelets 55% postoperatively. Plasma hemoglobin increased moderately, from preperfusion average valve of 7.79 mg % to post-perfusion value of 54.7 mg %. Electrolytes changes during cardiopulmonary bypass showed definite hypokalemia but changes of Na, Ca were not definite. Arterial blood gas analysis during cardiopulmonary bypass suggested that the metabolic acidosis which was accompanied by respiratory alkalosis which was corrected postoperatively. As the opera tive complication, transient hemoglobinuria in 4 cases and neurological signs in 2 cases were all cured. There were 2 death cases and operative mortality rate was 12.5%.

• Journal of Veterinary Clinics
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• v.30 no.4
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• pp.310-314
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• 2013

A 12-year-old, female mixed breed dog presented with a vaginal mass protruding outside the vulva. The patient was non-gravid, with normal defecation and urination. Serum chemistry revealed azotemia and increased alkaline phosphatase. Hematology findings were normal. Blood electrolytes showed mild hypernatremia. Ultrasonography demonstrated severely enlarged uterine horns, a uterine body with anechoic to hypoechoic fluids, and a focal hypoechoic area within the mass of the right uterine tube. On computed tomography, metastasis was not confirmed. Other computed tomography findings suggested a right ovarian cyst, an enlarged, fluid-filled uterus, and an enlarged vagina with a mass. Ovariohysterectomy, episiotomy, and vaginectomy were performed. The case was diagnosed as uterine tube adenocarcinoma, vaginal fibroma, and pyometra. This case is the first reported concurrent occurrence in dogs.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.5
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• pp.501-509
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• 2016

In this study, a flat-type photocatalytic reactor is applied under solar irradiation for simultaneous treatment of target pollutants: reduction of Cr(VI) to Cr(III) and oxidation of EDCs (BPA, EE2, E2). An immobilized type of photocatalyst was fabricated to have self-grown nanotubes on its surface in order to overcome limitations of powdery photocatalyst. Moreover, Ti mesh form was chosen as substrate and modified to have both larger surface area and photocatalyst content. Ti mesh was anodized at 50V and $25^{\circ}C$ for 30min in the mixed electrolytes ($NH_4F-H_2O-C_2H_6O_2$) and annealed at $450^{\circ}C$ for 2 hours in ambient oxygen to have anatase structure. Surface characterization was done with SEM and XRD methodologies. Fabricated NTT was applied to water treatment, and coexisting Cr(VI) and organics (EDCs) enhanced each other's reactions by scavenging holes and electrons and thus impeding recombination. Also, several experiments were conducted outdoor under direct sunlight and it was observed that both solar-tracking and applying modified photocatalyst were proven to enhance reaction efficiency.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.75.2-75.2
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• 2013

Atomic layer deposition (ALD), utilizing self-limiting surface reactions, could offer promising perspectives for future efficient energy conversion devices. The capabilities of ALD for surface/interface modification and construction of novel architectures with sub-nanometer precision and exceptional conformality over high aspect ratio make it more valuable than any other deposition methods in nanoscale science and technology. In the context, a variety of researches on fabrication of active materials for energy conversion applications by ALD are emerging. Among those materials, one-dimensional nanotubular titanium dioxide, providing not only high specific surface area but also efficient carrier transport pathway, is a class of the most intensively explored materials for energy conversion systems, such as photovoltaic cells and photo/electrochemical devices. The monodisperse, stoichiometric, anatase, TiO2 nanotubes with smooth surface morphology and controlled wall thickness were fabricated via low-temperature template-directed ALD followed by subsequent annealing. The ALD-grown, anatase, TiO2 nanotubes in alumina template show unusual crystal growth behavior which allows to form remarkably large grains along axial direction over certain wall thickness. We also fabricated dye-sensitized solar cells (DSCs) introducing our anatase TiO2 nanotubes as photoanodes, and studied the effect of blocking layer, TiO2 thin films formed by ALD, on overall device efficiency. The photon convertsion efficiency ~7% were measured for our TiO2 nanotubebased DSCs with blocking layers, which is ~1% higher than ones without blocking layer. We also performed open circuit voltage decay measurement to estimate recombination rate in our cells, which is 3 times longer than conventional nanoparticulate photoanodes. The high efficiency of our ALD-grown, anatase, TiO2 nanotube-based DSCs may be attributed to both enhanced charge transport property of our TiO2 nanotubes photoanode and the suppression of recombination at the interface between transparent conducting electrode and iodine electrolytes by blocking layer.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.85-88
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• 1985

Leakage of electrolytes from leaf discs of treated bean (Phaseolus velgaris L.) plant was the criterion used to investigate the effect of four herbicides on the permeability of leaf-cell membrane. CGA 82725 (2-propynyl 2-((3, 5-dichloro-2 pyridinyl) oxy) phenoxy prpanate) at $10^{-3}M$ increased significantly cell membrane permeability within 1 h after 12 h treatment. Significant increase in cell membrane permeability was also detected at $10^{-2}M$ of DOWCO 453 (Haloxy-methyl 2-(4 (3-chloro- 5-(trifuluoromethyl)-2-pyridinyl) phenoxy) propanate. The effect of dinoseb (2-(1-methylpropyl)-4, 6-dintrophenol) on cell premeability was detected at $10^{-4}M$ after 12h. The highest conductivity measurement was obtained from paraquat (1, 1'- dimethyl-4, 4'-bipyridinium ion). Increase in cell membrane permeability was not always associated with injury symptoms such as appearance of necrotic area in leaves.

• Applied Chemistry for Engineering
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• v.10 no.8
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• pp.1192-1199
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• 1999

The morphology changes of cadmium hydroxide into ${\gamma}$ phase by eletrolytes were carried out to improve the high rate charge and discharge efficiency of pasted cadmium electrodes. KOH solutions with different concentrations of NaOH were used as eletrolytes. It was found that the utilization of active material of cadmium electrode was the best in an electrolyte with 1.82 M NaOH. The amount of ${\gamma}-Cd(OH)_2$ increased in proportion to the concentration of NaOH. The surface area measurement showed that an active material which contained mainly ${\gamma}-Cd(OH)_2$ had a higher specific surface area than an active material of ${\beta}-Cd(OH)_2$. In a sealed cell, the discharge capacity was improved at high rate charge and discharge (1.0 C, 2.0 C) by using an electrolyte with NaOH. Furthermore, these improved performances were maintained up to 500 cycles at 1.0 C rate charge and discharge cycles.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.308-312
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• 2013

Active carbons with high specific surface area and micro pore structure were prepared from the coconut shell char using the chemical activation method of NaOH. The preparation process has been optimized through the analysis of experimental variables such as activating chemical agents to char ratio and the flow rate of gas during carbonization. The active carbons with the surface area (2,481 $m^2/g$) and mean pore size (2.32 nm) were obtained by chemical activation with NaOH. The electrochemical performances of hybrid capacitor were investigated using $LiMn_2O_4$, $LiCoO_2$ as the positive electrode and prepared active carbon as the negative electrode. The electrochemical behaviors of hybrid capacitor using organic electrolytes ($LiPF_6$, $TEABF_4$) were characterized by constant current charge/discharge, cyclic voltammetry, cycle and leakage tests. The hybrid capacitor using $LiMn_2O_4$/AC electrodes had better capacitance than other hybrid systems and was able to deliver a specific energy as high as 131 Wh/kg at a specific power of 1,448 W/kg.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.3
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• pp.110-116
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• 1981

Soil surface charge which manipulates some important soil physico-chemical properties such as nutrient and water holding abilities, colloidal stability and soil erosion was investigated in wide range of soil pH, using soils developed originally from same volcanic ash deposit but under different rainfall condition in Hawaii. The results can be summarized as follows : 1. Ustollic Camorthid (Kawaihae soil) which was developed under the lowest rainfall (less than 500 mm/yr) revealed low Z.P.C. (4.5-5.0) and less dependence of net charge on concentration of indifferent electrolytes. 2. Typic Hydrandepts (Akaka and Hilo soils) which were developed under the high rainfall (3050-7600 mm/yr) showed the Z.P.C. in between 5.5-7.0 and high dependence of net charge on concentration of indifferent electroytes. 3. It was found by X-ray diffraction together with total chemical analysis that amorphous materials were dominant (above 6.0%) in Typic Hydrandepts while dehydrated halloy-site (1 : 1 clay minerals) was dominant (45-50%) in Ustollic Camorthid. 4. In spite of little difference in particle size distribution of the soils, the difference of specific surface area was remarkable showing the order of Akaka (289) > Hilo (268) > Kawaihae (93). 5. It was evident, taking account of apparent field pH values, 5.2 of Akaka, 5.5 of Hilo and 7.0 of Kawaihae soil, respectively, that Akaka, and Hilo soils would show either positive or near zero (+ or 0) of ${\Delta}pH$ while Kawaihae soil would exhibit negative (-) of ${\Delta}pH$ at natural field condition.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.180-187
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• 2015

This study was conducted to determine the effects of feeding by-product feed (BF)-based silage on the performance, blood metabolite parameters, and carcass characteristics of Hanwoo steers. The BF-based silage was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% cut ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial additive (on a wet basis), and ensiled for over 5 d. Fifteen steers were allocated to three diets during the growing and fattening periods (3.1 and 9.8 months, respectively): a control diet (concentrate mix and free access to rice straw), a 50% BF-based silage diet (control diet+50% of maximum BF-based silage intake), and a 100% BF-based silage diet (the same amount of concentrate mix and ad libitum BF-based silage). The BF-based silage was fed during the growing and fattening periods, and was replaced with larger particles of rice straw during the finishing period. After 19.6 months of the whole period all the steers were slaughtered. Compared with feeding rice straw, feeding BF-based silage tended (p = 0.10) to increase the average daily gain (27%) and feed efficiency (18%) of the growing steers, caused by increased voluntary feed intake. Feeding BF-based silage had little effect on serum constituents, electrolytes, enzymes, or the blood cell profiles of fattening steers, except for low serum Ca and high blood urea concentrations (p<0.05). Feeding BF-based silage did not affect cold carcass weight, yield traits such as back fat thickness, longissimus muscle area, yield index or yield grade, or quality traits such as meat color, fat color, texture, maturity, marbling score, or quality grade. However, it improved good quality grade (1+ and 1++) appearance rates (60% for the control group vs 100% for the BF-based silage-fed groups). In conclusion, cheap BF-based silage could be successfully used as a good quality roughage source for beef cattle.