• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.4
• /
• pp.723-731
• /
• 2000

In recent years, the amount and number of synthetic organic compounds(SOCs) discharged from various industries has been increasing. Granular activated carbon(GAC) adsorption is one of the best available technology to remove SOCs from water supplies and wastewater. In this paper competitive adsorption for binary mixture of 4-nitrophenol and phenol on reverse stratified tapered adsorber(RSTA) using GAC was studied. Two isotherm experiments were conducted, one for phenol and the other for 4-nitrophenol. The phenol data of binary mixture isotherm were not fitted to Freundlich isotherm. The competitive adsorption increased significantly with decreasing carbon dose and increasing adsorbate concentration. The RSTA was found to provide an increase in breakthrough time when decreasing flow rate, increasing angle and injection layers. The performance enhancement provided by RSTA can be exploited in separation and in the purification of fluids.

• Resources Recycling
• /
• v.26 no.6
• /
• pp.45-49
• /
• 2017

Most Waste slurry is produced in the process of silicon manufacturing for semiconductor industry, containing silicon (Si) and silicon carbide (SiC). Waste slurry is simply stored with solidifying by cement or buried. On the other hand, it was suggested in this study that the waste slurry should be used for heating source as supplementary material in steel making process. The waste slurry was refined and pulverized, which was recycled into SiC-based sludge briquette. Chemical composition for SiC-based sludge briquette was analyzed and the feature of heating source was observed in accordance with the injection time and input amount. As a result, SiC-based sludge briquette in terms of low cost and high efficiency had an effect on increasing liquid steel temperature in steel making plants.

• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.4
• /
• pp.338-342
• /
• 2004

This study was performed to measure the antioxidant effects of red ginseng extracts which antioxidation had been promoted through enzyme hydrolysis. In order to observe their tumor-suppressing effects, an anti-cancer medicine and Saponin-SOD, which was a highly antioxidant beverage made from red ginseng saponin adding SOD-like rice (with embryo buds) extracts, were administered to nude mice with large intestine cancer induced. There was a significant increase in the content of phenolic compounds as the enzyme was added. The red ginseng extracts showed a high electron-donating ability with the passage of time. The electron-donating ability was particularly high in the enzyme-treated red ginseng extract, and also observed as high in Saponin-SOD. The lipid-peroxide generation was inhibited depending on the concentration of Saponin-SOD added; the addition of 0.625% Saponin-SOD served to decrease the inhibition level up to 65% compared with the case of no addition (100%). As a result, it could be assumed that Saponin-SOD would strongly inhibit the oxidation of ghost membrane. After the cancer was induced in nude mice through the injection of SNUC-4 cell, there was a significant inhibition in the growth of tumors in nude mice into which Saponin-SOD were injected; the growth of tumors was gradually decreasing with the passage of time after the cancer induction. In particular, when Saponin-SOD was administered together with an anti-cancer medicine, the synergic effect was observed. In conclusion, Saponin-SOD, when used with an anti-cancer medicine, is expected to reduce the amount of free radical and lipid peroxide, which are known to cause harmful effects occurring from the internal application of medicine.

• Clinical and Experimental Reproductive Medicine
• /
• v.47 no.1
• /
• pp.20-33
• /
• 2020

Objective: The differences between type 1 and type 2 diabetes mellitus (T1DM and T2DM) in terms of their adverse effects on male reproductive parameters have never been elucidated. This study aimed to distinguish between the effects of the DM types in mice treated with multiple low doses of streptozotocin (STZ) to mimic human T1DM and coadministered a high-fat diet (HFD) to mimic human T2DM. Methods: The T1DM mice were intraperitoneally injected with STZ (40 mg/kg body weight) for 5 days. The T2DM mice received an HFD for 14 days prior to STZ injection (85 mg/kg body weight), followed by continuous feeding of an HFD. Male reproductive parameters were evaluated. Results: The reproductive organs of the DM mice weighed significantly less than those of controls, and the seminal vesicles plus prostates of the T1DM mice weighed less than those of the T2DM mice. Increased sperm abnormalities and incomplete DNA packaging were observed in the DM groups. Sperm concentration and the proportion of normal sperm were significantly lower in the T1DM group. The seminiferous histopathology of DM mice was classified into seven types. The penises of the DM mice were smaller than those of the controls; however, tunica albuginea thickness and the amount of penile collagen fibers were increased in these mice. Round germ cells were abundant in the epididymal lumens of the mice with DM. Conclusion: T1DM adversely affected reproductive parameters to a greater extent than T2DM.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.682-685
• /
• 2017

An experimental study was carried out to investigate the injection characteristics of non-circular effervescent type twin-fluid nozzles. For this purpose, two types of non-circular nozzles (E1, E2) and one kind of circular nozzle (C) were used. At this time, the Aerorator mounted on the nozzle used three different diameters to match the aspect ratio with the nozzle exit area. Therefore, experiments were performed according to three aspect ratios for each nozzle, and a total experiments were conducted. Experiments were carried out by controlling the amount of air flowing after fixing the flow rate of the liquid, and the nozzle internal pressure and SMD were measured, and the jet image was taken from the nozzle. The discharge coefficients of the three kinds of nozzles were compared with the conventional equation and the Jedelsky's equation, and the Jedelsky's equation was found to be about 4 times larger. The droplet size (SMD) injected from the nozzle was found to be smaller in the non-circular shape than in the circular shape, which is expected to be caused by the difference of the discharge coefficient values.

• Polymer(Korea)
• /
• v.36 no.4
• /
• pp.461-469
• /
• 2012

The surface modification and characterization of Ar-plasma treated polypropylene (PP) blend are investigated using x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and contact angle measurement. An increase in Ar-plasma treatment time leads to an increase in wettability, oxygen containing polar functional groups, the amount of talc, and surface roughness on the PP blend surface. A careful observation using SEM indicates that there exists a skin layer consisting of only PP component. The difference in viscosity between PP and rubber particles facilities the formation of skin layer. However, it is found that an increase in Ar-plasma treatment time helps to decrease the thickness of skin layer. Additional methodologies for the elimination of skin layer during injection molding are also discussed. The surface modification and morphological alteration induced by Ar-plasma treatment provides a hydrophilic state, followed by the improvement in wettability, on the PP blend surface.

• YAKHAK HOEJI
• /
• v.55 no.5
• /
• pp.379-384
• /
• 2011

The aim of this study was to reduce the side effects and to develop effective drugs using bucillamine (B), lornoxicam (L), and its mixtures on the analgesic and anti-inflammatory effects. With this goal, we compared their effects on the four different mixtures with a sole treatment (B 40 mg/kg and L 1.60 mg/kg). The mixture 1, 2, 3, and 4 ratios of B to L (mg/kg) were 20 to 0.80, 40 to 1.60, 80 to 3.20, and 40 to 1.14, respectively. In terms of acetic acid-induced vascular permeability, B and L inhibited the amount of dye leakage approximately 37.8 and 66.5%, respectively. And mixture 1, 2 and 3 showed inhibition of 47.4%, 81.5%, and 84.3%. The mixture 4 inhibited approximately 49.4%. In carrageenan- induced paw edema model, mixtures of B and L effectively inhibited paw edema measured 1/2~3 hours after carrageenan injection. Especially, mixture 2 inhibited 50.7%, 52.7%, 50.9% of paw edema after 1, 2, and 3 hr, significantly. We also examined an analgesic effect using the writhing test. In terms of the acetic acid-induced writhing syndrome, the control group showed writhing syndrome 18.5 times. B and L showed 9 and 6.3 times, inhibiting 51.6% and 65.9% respectively. And aspirin, as a positive control drug, showed the 7.1 times writhing syndrome. The mixture 1, 2, 3, and 4 also significantly inhibited the writhing syndrome to 62.2%, 93.0%, 51.4%, and 77.8%, respectively. From these results, we could suggest that the range of B and L ratio of 25 : 1 to 35 : 1 may be applicable to developing analgesic and anti-inflammatory drugs.

• Journal of the Korean Geotechnical Society
• /
• v.19 no.2
• /
• pp.159-170
• /
• 2003

In this study, the mixed design of grout with hish strength.high permeation.high durability and environmental stability as the state of the art in material field was performed. Also, the subjects of grouting, grouting effects for ground conditions, and environmental effects were analyzed. According to these results, the fundamental data will be suggested as a design of grouting in the field application. The physical, mechanical and chemical characteristics with particle shape of the grouts were analyzed. Then, the gel-time of grouts, which is essential for workability and permeation range, were controlled. Also, the laboratory model grouting tests were performed to find the characteristics of solidification, permeation and durability with grouts. The ordinary portland, slag and microcement which have been used in the construction field were evaluated fur the environmental effects. To find the leaching of $Cr^{6+}$characteristics in cement grouts, $Cr^{6+}$ leaching tests were performed for the raw materials. Also, the results of leaching test were shorn by surrounding environment. Then, the unconfined compression strength tests were performed with the homo-gel samples, and the amount of changed $Cr^{6+}$ was measured by curing solution.

• Journal of Hydrogen and New Energy
• /
• v.23 no.5
• /
• pp.530-537
• /
• 2012

This work experimentally investigates that Diesel-DME blended fuel influences combustion characteristics and emissions (NOx, CO, HC, smoke) in a single-cylinder DI diesel engine. Diesel is used as a main fuel and DME is blended for the use of its quick evaporating characteristics. Diesel and DME are blended by the method of weight ratio. Weight ratios for Diesel and DME are 95:5 and 90:10 respectively and the both ratios have been used altogether in blended fuel. The experiments are conducted in this study single cylinder engine is equipped with common rail and injection pressure is 700 bar at 1200 rpm. The amount of injected fuels is adjusted to obtain the fixed input calorie value as 972.2 J/cycle in order to compare with the fuel conditions. DME is compressed to 15 bar by using nitrogen gas thus it can be maintained the liquid phase. In this study, different system compared others paper is common rail system, also there is combustion and emission about compared DME and diesel fuel. It is expected to be utilized about blended fuel.

• Journal of Periodontal and Implant Science
• /
• v.31 no.2
• /
• pp.389-400
• /
• 2001

Previous studies have demonstrated an increase in bone mass and density with the use of bisphosphonate in osteoporosis. This agent acts as an inhibitor of osteoclastic activity, and results in increase of net osteoblastic activity. Currently, it has been reported that bisphosphonate has direct effect on osteoblast. This study was designed to evaluate the effect of alendronate on bone regeneration in defect of rat calvaria. The animals used for these experiments were 48 male rats, over 6-8 weeks old. They were divided into three groups according to the dose of alendronate($MK-217^{(R)}$, Merck, USA) administered. After the calvarial defects were surgically created, the rats received a peritoneal alendronate(0.25mg/kg) in group I, a peritoneal alendronate(1.25mg/kg) in group II, and a peritoneal normal saline injection in the control group. Three and six weeks later, blood was sampled and evaluated for alkaline phosphatase activity. The animals were sacrificed for histological observation and histometric analysis of the level of bone formation. The alkaline phosphatase activity was similar in three groups at 3 weeks of experiment. The activity at 6 weeks increased more than twice, compared to 3 weeks, and was slightly higher in group I than the other two groups. In histological observation, all the groups at 3 weeks, osteoblast rimming and new bone formation were observed along the defect margin. At 6 weeks, the defect was almost closed with new and more mature bone, but new bone is thinner than original bone in the central portion of defect. In histometric analysis, group I and II at 3 weeks showed significantly greater new bone formation than the control, and all the groups at 6 weeks showed similar amount of bone formation. These result suggest that alendronate administration in the dose of 0.25mg/kg and 1.25mg/kg promote osseous regeneration.