• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.77-83
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• 1983

Effects of rice straw application (particularly application method; surface placement and deep placement) on the biological nitrogen fixing activity of paddy fields and on the growth of rice plant have been investigated by the lysimeter experiment with Aragawa alluvial soil and Tochigi ando soil. 1. Nitrogen fixing activity of plow layer (0~1cm) was increased by the rice straw application, notably by the phototrophs, both deep placement and surface placement, between 1 and 2 months of initial growth stage of rice plant. 2. Surface placement method stimulated the nitrogen fixing activity more significantly them the deep placement method, and also showed good effects on the growth of rice plant. 3. The increased of effect on the nitrogen fixing activity of surface placed area was found to be originated from the applied rice straw and its neigh bouring area. 4. Nitrogen fixing activity of surface placed rice straw was rather promoted by the application of herbicides (2, 4, 6-arichlorophenyl ether) than the non-applicated plot.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.228-236
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• 2016

The purpose of this study was to determine the optimum conditions of solvent extraction type and solvent concentration (60, 70, 80%, v/v), extraction time (30, 80, 130 mins) and extraction temperature (10, 15, $20^{\circ}C$) in order to increase the antioxidant activity of the chia seed. The total polyphenol content and DPPH radical scavenging activity was measured by using response surface methodology (RSM) to establish the optimal conditions. Using ethanol and methanol extractions at extraction concentrations of 60%, and time and temperature of 130 mins and $20^{\circ}C$, the maximum total polyphenol content was 871.00 mg% ($R^2=0.9507$) and 557.70 mg% ($R^2=0.9784$) for ethanol and methanol extraction respectively. Using the same extraction conditions, the maximum level of DPPH radical scavenging activity was 72.14% ($R^2=0.9675$) and 52.79% ($R^2=0.9524$) for ethanol and methanol extraction respectively. The results indicate that ethanol extracts showed a higher antioxidant activity than methanol extracts. The ethanol extraction conditions of response surface analysis (RSA) were affected more by ethanol concentration than by extraction time or temperature. In contrast, the methanol extraction conditions of response surface analysis (RSA) were affected more by extraction time. Based on the RSM, the optimum ethanol extraction conditions were the following: extraction concentration, 63%: time, 100 mins: and temperature, $18^{\circ}C$. The optimum methanol extraction conditions were the following: extraction concentration, 65%; time, 120 mins; and temperature, $16^{\circ}C$.

• Physical Therapy Korea
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• v.24 no.1
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• pp.86-96
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• 2017

Background: Scapular dyskinesis is characterized by altered scapular position and motion. Specifically, excess activation of the Upper trapezius (UT) combined with decreased Lower trapezius (LT) and Serratus anterior (SA) have been observed. The Standard push-up plus exercise (SPP) is considered as a therapeutic exercise for increasing SA activity and maintaining the scapular kinematics. In addition, Using the Sling surface can lead to higher muscle activity. However, the advantage of an unstable surface has been uncertatin. Objects: To compare the activation of the UT, LT, and lower serratus anterior (LSA) muscles during various push-up plus exercises with and without sling in subjects with scapular dyskinesis. Methods: Total 18 male subjects with scapular dyskinesis were recruited. The UT, LT, and LSA electromyographic activities and the UT/LSA and UT/LT EMG activity ratios were measured during three push-up plus exercises with and without sling. Two-way repeated of analysis of variance was used to determine the statistical significance. Results: The UT activity was significantly lower in all postures without sling than that with sling. In addition, the LSA activity was significantly greater without than with sling, and significantly large in SPP, Low back supported push-up plus (LSPP), and Quadruped push-up plus. Additionally, the UT/LSA and UT/LT activity ratios were lower in SPP and LSPP without sling than with the other four push-up plus exercises. Conclusion: The push-up plus without sling were considered to decrease UT and increase LSA activity compared with exercises with sling. Furthermore, SPP without sling seems to be a more effective exercise for increasing LSA activity and lowering the UT/LSA and UT/LT activity ratios in scapular dyskinesis subjects.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1423-1428
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• 2006

In this study, we have prepared pitch binded AC (activated carbon)/$AC/TiO_2$ composites photocatalysts through carbon tetrachloride solvent method. The developed samples were characterized with surface properties, structural crystallinity between AC and $AC/TiO_2$, elemental identification and photocatalytic activity. The results of the textural surface properties demonstrate that there are slight increases in the BET surface area and adsorbed volume from adsorption isotherm of composite samples with increasing of the amount of AC. The SEM results present to the characterization of porous texture on the pitch/AC/$AC/TiO_2$ composites and homogenous compositions in the particle for all the materials used. From XRD data, a weak and broad carbon peak of graphene remained rutile peaks kept with anatase structure were observed in the X-ray diffraction patterns for the pitch/AC/$AC/TiO_2$ composites. The EDX spectra show the presence of C, O and S with strong Ti peaks. Most of these samples are richer in carbon and major Ti metal than any other elements. Finally, the excellent photocatalytic activity of the pitch/AC/$AC/TiO_2$ composites between relative concentration ($c/c_o$) of MB and UV irradiation time could be attributed to the both effects between photocatalysis of the supported $AC/TiO_2$ and adsorptivity of the two kinds of carbons.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.283-291
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• 2010

The purpose of this study was to investigate the effect of foot placement and height of bed surface on lumbar spine load in a dummy transfer activity. Fifteen healthy male students participated in this study. All subjects were involved in four different conditions according to foot placement (11 figure and $90^{\circ}$ figure) and height of bed surface (44 cm and 66 cm) randomly. Muscular activations of the biceps brachii, rectus femoris, elector spinae using surface-EMG, vertical ground reaction using force plate, and L4/L5 compression force using 3DSSPP (3D Static Strength Prediction Program) were measured and analysed. The results showed that muscular activations were not significantly different for the various conditions except for the rectus femoris on the right side (p<.05). Futhermore, the vertical ground reaction and L4/L5 compression force were significantly different conditions (p<.05). In conclusion, it is suggested that foot placement at $90^{\circ}$ figure is safer for transfer activity compared with the 11 figure.

• The Korean Journal of Ceramics
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• v.6 no.4
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• pp.339-342
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• 2000

In the present study, we attempted to apply DV-X$\alpha$ method to expressing the reactivity of materials. The expression of reactivity was discussed by comparison between ${\gamma}$-C$_2$G having hydraulic activity and ${\gamma}$-C$_2$S not having hydraulic activity at normal conditions. It was found that the model cluster used for calculation can finely reproduce the bulk and surface states using with and without point charge, respectively. The hydration state was also represented by placing OH￣ on the surface of the cluster. It was calculated that the bond strength of the first layer (as surface) was bigger than that of inner layers (as bulk) for ${\gamma}$-C$_2$S while that of the first layer for ${\gamma}$-C$_2$G was smaller than that of inner layers. Subsequently a model in which OH￣ is coordinated on Ca at the surface was also calculated. The bond strength with OH￣ was stronger than that without OH￣, while for ${\gamma}$-C$_2$G the bond strength with OH￣ was weaker than that without OH￣. From these results, it is concluded that the hydraulic activity depends on whether the bond strength for hydrated state becomes weaker than that unhydrated state or not.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.317.2-317.2
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• 2013

Ultrathin oxide encapsulated metal-oxide hybrid nanocatalysts have been fabricated by a soft chemical and facile route. First, SiO2 nanoparticles of 25~30 nm size have been synthesized by modified Stobber's method followed by amine functionalization. Metal nanoparticles (Ru, Rh, Pt) capped with polymer/citrate have been deposited on functionalized SiO2 and finally an ultrathin layer of TiO2 coated on surface which prevents sintering and provides high thermal stability while maximizing the metal-oxide interface for higher catalytic activity. TEM studies confirmed that 2.5 nm sized metal nanoparticles are well dispersed and distributed throughout the surface of 25 nm SiO2 nanoparticles with a 3-4 nm TiO2 ultrathin layer. The metal nanoparticles are still well exposed to outer surface, being enabled for surface characterization and catalytic activity. Even after calcination at $600^{\circ}C$, the structure and morphology of hybrid nanocatalysts remain intact confirm the high thermal stability. XPS spectra of hybrid nanocatalyst suggest the metallic states as well as their corresponding oxide states. The catalytic activity has been evaluated for high temperature CO oxidation reaction as well as photocatalytic H2 generation under solar simulation. The design of hybrid structure, high thermal stability, and better exposure of metal active sites are the key parameters for the high catalytic activity. The maximization of metal-TiO2 interface interaction has the great role in photocatalytic H2 production.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.369-372
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• 2009

In the present study, the effect of chemical treatment on graphite nanofibers (GNFs) supports with various concentrated nitric acids was investigated for methanol oxidation. To optimize the electrocatalytic activity, PtRu catalysts were deposited on GNF supports by impregnation method. The surface and structural properties of the GNF supports were characterized by X-ray photoelectron spectroscopy (XPS), element analyzer (EA), and X-ray diffraction (XRD). The morphology of the catalysts was observed by means of transmission electron microscopy (TEM). The electrocatalytic activity of PtRu/GNF catalysts was investigated by cyclic voltammetry measurement. As a result, the oxygen functional groups were introduced on the GNF supports and were gradually increased with increasing of concentrated nitric acid, causing the smaller particle size and higher loading level. And the electrocatalytic activity of the catalysts for methanol oxidation was gradually improved. Consequently, it was found that chemical treatments could influence on surface properties of the carbon supports, resulting in enhancing the electrocatalytic activity of the catalysts for DMFCs.

• Korean Journal of Applied Biomechanics
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• v.25 no.3
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• pp.301-309
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• 2015

Objective : The purpose of this study was to describe the correlation between the activity of the muscles of upper and lower limbs of a golf driver swing according to shoulder injury. Method : The subjects were 18 professional golfers (7 male in KPGA and 11 female in KLPGA). Using surface electromyography, we evaluated muscle activities during the golf drive swing. Surface electrodes were used to record the level of muscle activity in the left Deltoid(MD), Triceps Brachii(TB), Pectoralis(PM), Trapezius(UT), Rectus Femoris(RF), Vastus Medialis Obilique(VMO), Biceps Femoris(BF), Gastrocnemius(GCM) muscles during the golfer's swing. The golf swing was divided into five phases: take away, forward swing, acceleration, early follow through, late follow through. Results : The results can be summarized as follows: MD, VMO had statistically significant difference in take away phases, GCM had statistically significant difference in acceleration phases, MD, PM, VMO had statistically significant difference in early follow through phases, PM had statistically significant difference in late follow through phases, Conclusion : Muscle activity of the 8 muscles(Deltoid, Triceps Brachii, Pectoralis, Trapezius, Rectus Femoris, Vastus Medialis Obilique, Biceps Femoris, Gastrocnemius) along the shoulder damage or absence of has shown that they are organically connected to each of the phases.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.851-861
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• 2005

The nature of the implant surface can directly influence cellular response, ultimately affecting the rate and quality of new bone tissue formation. The aim of this in vitro study was to investigate if human osteoblast-like cells, Saos-2, would respond differently when plated on disks of magnesium titanate and machined titanium. Magnesium titanate disks were prepared using Micro Arc Oxidation(MAO) methods. Control samples were machined commercially pure titanium disks. The cell adhesion, proliferation and differentiation were evaluated by measuring cell number, and alkaline phosphatase(ALPase) activity at 1 day and 6 day after plating on the titanium disks. Measurement of cell number and ALPase activity in Saos-2 cells at 1 day did not demonstrate any difference between machined titanium and magnesium titanate. When compared to machined titanium disks, the number of cells was reduced on the magnesium titanate disks at 6 day, while ALPase activity was more pronounced on the magnesium titanate. Enhanced differentiation of cells grown on magnesium titanate samples was indicated by decreased cell proliferation and increased ALPase activity.