• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.663-682
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• 2000

The purpose of this study was to identify the superior exercise on the reduction of low back pain, between the Mckenzie exercise and the williams exercise. 24 chronic low back pain patients were randomly divided into 3 groups (Mckenzie exercise group = 8, williams exercise group = 8, control group = 8). Each group examined using the Borg scale in a reduction of low back pain, the EMG amplitude in a stationary sit-up position and in a stationary 1000 back extension position. The Results are as follow. 1. After the training period, the Mckenzie exercise group and the williams exercise group revealed reduction of low back pain, but the control group does not revealed it. 2. After the training period, there were no significant differences on the reduction of low back pain between the Mckenzie exercise group and the williams exercise group. 3. After the training period, no groups decreased on the abdominal muscle EMG amplitude. 4. After the training period, all groups revealed no significant differences on the abdominal muscle EMG amplitude. 5. After the training period, all groups decreased on the low back muscle EMG amplitude. 6. After the training period, all groups revealed no significant differences on the low back muscle EMG amplitude. Overall, the study suggested that the Mckenzie exercise and the williams exercise achieve the same effect on the reduction of low back pain, and the fact seems to be influenced by other factors without muscular adaptation.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1317-1319
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• 1995

In this paper, we studied reduction characteristics of NOx gas produced from diesel engine combustion using by point-plane electrode. Here, input voltage forms were types of three [DC, AC, DC Positive pulse] and NOx gas of 1700ppm was composed of NO 1665ppm, $NO_2$ 35ppm on balance of $N_2$. We investigated NOx reduction characteristics as various of parameters, are gas flow rate, input voltage form and, humidity. From the results of study, reduction characteristics of NOx exhibited good when gas flow rate was small, input voltage was DC and much humidity were contained to NOx gas.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.186-188
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• 1963

An attempt to improve the method of volumetric determination of tungsten developed by Luke has been made successfully. Using amalgam coated lead instead of pure metallic lead in the reduction procedure. W(VI)-W(III) reduction has been found to be quantitative in rather concentrated hydrochloric acid. Since there was no excessive dissolution of lead via reduction of hydrogen ion, lead surface was totally accessible for the reduction of tungsten and no trouble was caused by dereposition of $PbCl_2$ crystals at the nozzle of Jones reductor. Furthermore, it has been confirmed that almost 100 mg. of $WO_3$ can be handled easily if the chloride concentration of the HCl is increased by adding solid $NH_4Cl$.

• Economic and Environmental Geology
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• v.50 no.1
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• pp.27-34
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• 2017

Mineral carbonation for the storage of carbon dioxide is a CCS option that provides an alternative for the more widely advocated method of geological storage in underground formation. Carbonation of magnesium- or calcium-based minerals, especially the carbonation of waste materials and industrial by-products is expanding, even though total amounts of the industrial waste are too small to substantially reduce the $CO_2$ emissions. The mineral carbonation was performed with steelmaking reduction slag as starting material. The steelmaking reduction slag dissolution experiments were conducted in the $H_2SO_4$ and $NH_4NO_3$ solution with concentration range of 0.3 to 1 M at $100^{\circ}C$ and $150^{\circ}C$. The hydrothermal treatment was performed to the starting material via a modified direct aqueous carbonation process at the same leaching temperature. The initial pH of the solution was adjusted to 12 and $CO_2$ partial pressure was 1MPa for the carbonation. The carbonation rate after extracting $Ca^^{2+}$ under $NH_4NO_3$ was higher than that under $H_2SO_4$ and the carbonation rates in 1M $NH_4NO_3$ solution at $150^{\circ}C$ was dramatically enhanced about 93%. In this condition well-faceted rhombohedral calcite, and rod or flower-shaped aragonite were appeared together in products. As the concentration of $H_2SO_4$ increased, the formation of gypsum was predominant and the carbonation rate decreased sharply. Therefore it is considered that the selection of the leaching solution which does not affect the starting material is important in the carbonation reaction.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.888-894
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• 1993

The electrochemical behaviors of copper-1-(2-pyridylazo)-2-naphthol(Cu-PAN) complex in acetonitrile (AN) solution have been investigated by the use of cyclic voltammetry, DC-polarography, controlled potential coulometry and UV-Vis spectroscopy. Cu-PAN complex in acetonitrile exhibit three reduction waves at -1.27 V, -1.64 V and -2.08 V vs. Ag/AgNO$_3$(AN). The numbers of electron involved in each reduction step was calculated with controlled potential coulometry, and reduction product was identified with UV-Vis spectrum. As the result, we proposed the reduction mechanism of the Cu-PAN complex in acetonitrile.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.503-518
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• 2012

Korean type of no-tillage cultivation method which was applied on this study used the ridge and the furrow and constantly recycling them as it was suitable for Korea's weather and farming conditions. This no-tillage cultivation was reported to have little negative impact such as reduction of production (Kwon et al., 1997). In addition, it was found to have a lot of benefits as it requires less agro-materials and energy costs as well as shortened working hours because tillage operation is not needed. (Yang et al., 2012). According to an analysis, no-tillage cultivation can reduce greenhouse gas emissions by $344.7kgCO^2$ (58%) in every 10a ($1,000m^2$) compared to ordinary pepper farming technique (Korea averages). Direct-indirect reduction effects from using fertilizer and using less amount of energy were 92% and 44% respectively both of which can be considered very high. Besides the direct effects of no-tillage cultivation, soil management using no-tillage technique raises carbon sequestration effect on soil as time goes on (West & Marland, 2002), that is why the technique is expected to have constant carbon emission reduction effect. For theses reasons, distribution and expansion of Korean type no-tillage cultivation are expected to play a role as major agro-green technologies for achieving our goal of reducing greenhouse gas emissions in agricultural sector.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.84-91
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• 2012

Single and few-layer graphene nanosheets (GNs) have successfully synthesized by a modified Hummer's method followed by chemical reduction of exfoliated graphene oxide (GO) in the presence of hydrazine monohydrate. GO and GNs were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), X-ray diffractions (XRD), Raman spectroscopy, Transmission electron microscopy (TEM), Atomic force microscopy (AFM), Optical microscopy (OM) and by electrical conductivity measurements. The result showed that electrical conductivity of GNs was significantly improved, from $4.2{\times}10^{-4}$ S/m for GO to 12 S/m for GNs, possibly due to the removal of oxygen-containing functional group during chemical reduction. In addition, the $NO_2$ gas sensing characteristics of GNs are also discussed.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.688-693
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• 2014

For investigating NO reduction activity of an catalytic filter, the catalytic performance was measured under the presence of $SO_2$ and $H_2O$, respectively or simultaneously in the simulation gas composed of NO, $NH_3$, and air. The catalytic filter was prepared by coating $V_2O_5-WO_3/TiO_2$ catalyst on the pore surface of SiC filter element of which the superior performance for the particulate removal was well known. At the temperature below $260^{\circ}C$, the catalytic activities were enormously decreased under the presence of $SO_2$ and $H_2O$, respectively or simultaneously, compared with those under the cases of the absence of $SO_2$ and $H_2O$. However, the presence of $SO_2$ promoted the performance of the catalytic filter above $320^{\circ}C$ with showing the NO conversion better than 99.8% for the NO inlet concentration of 500 ppm and at the face velocity of 2 cm/s. In particular, the presence of water showed high NO conversion higher than 99% up to high temperature of $380^{\circ}C$. This effect of water was explained by the reason that it retarded the ammonia oxidation which is the main step into the formation of $N_2O$. The initial NO reduction activity of the catalytic filter maintained for the duration of 100 hours in the presence of $SO_2$ and $H_2O$. Therefore, it was concluded that the catalytic filter was promisingly useful for the industrial NOx reduction catalyst in order to treat the particulate and NO simultaneously.

• Journal of Powder Materials
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• v.18 no.2
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• pp.159-167
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• 2011

The influence of sulfate on the selective catalytic reduction of $NO_x$ on the Ag/$Al_2O_3$ catalyst was studied when $CH_4$ was used as a reducing agent. Various preparation methods influenced differently on the $deNO_x$ activity. Among the methods, cogelation precipitation gave best activity. When sulfates were formed on the surfaces of samples prepared by impregnated and deposition precipitation, $deNO_x$ activity was enhanced as long as suitable forming condition is satisfied. The major sulfate formed in Ag/$Al_2O_3$ catalyst was the aluminum sulfate and it seems that this sulfate acted as a promoter. When Mg was added to the Ag/$Al_2O_3$ catalyst it promoted $deNO_x$ activity at high temperature. Intentionally added sulfate also enhanced $deNO_x$ activity, when their amount was confined less than 3 wt%.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.77-84
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• 2002

Measurements of NO and NOx emission of laminar partially premixed LPG/air flames with and without acoustic excitation are reported. The NOx emission at the tailpipe of a combustion chamber is determined by chemiluminescent analyser. The NOx measurements are taken in flames with several different center tube equivalance ratio( ø$\sub$o/), and overall equivalace ratio(ø$\sub$o/) for a fixed fuel flowrate. The NOx emission decrease to reach a minimum value at an optimum ø$\sub$c/ 2. Theø$\sub$c/ 2 flame gives a compromise of thermal NO and prompt NO mechanism. In the case of excitation. the visual shape of the flame is changed from laminar flame to turbulent-like flame. With increasing levels of excitation amplitude, an optimum value of the NO and NOx emission exists. A shorter flame caused by the enhanced upstream mixing due to acoustic excitation results in the reduction of NO and NOx emission in the present flames. The reduction of flame length affects the shorter residence time of center tube mixture, and significantly influences the NOx reduction.