• Resources Recycling
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• v.22 no.2
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• pp.18-21
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• 2013

In this study, surface modification of wood powder by atmospheric pressure plasma treatment was investigated. The composites were manufactured using wood powder and polypropylene(wood powder : PP = 55 wt% : 45 wt%). Atmospheric pressure plasma was treated as condition of 3KV, $17{\pm}1$KHz, 2 g/min. Helium was used as carrier gas and monomer such as hexamethyl-disiloxane(HMDSO) was used to modify surface property by plasma polymerization. The tensile strength of untreated waste wood powder(W3) and homogeneous wood powder(H3) were about 18.5 MPa, 21.5 MPa while the tensile strength of plasma treated waste wood powder(PW3) and homogeneous wood powder(PH3) were about 21.2 MPa, 23.4 MPa, respectively. And tensile strength of W3 and H3 were improved by 14.6% and 8.8%, respectively. From the results for mechanical property, morphological analysis, we obtained improved interfacial bonding of polypropylene and wood powder modified by plasma treatment.

• Korean Journal of Materials Research
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• v.24 no.8
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• pp.423-428
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• 2014

We synthesized Fe-doped $TiO_2/{\alpha}-Fe_2O_3$ core-shell nanowires(NWs) by means of a co-electrospinning method and demonstrated their magnetic properties. To investigate the structural, morphological, chemical, and magnetic properties of the samples, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were used, as was a vibrating sample magnetometer. The morphology of the nanostructures obtained after calcination at $500^{\circ}C$ exhibited core/shell NWs consisting of $TiO_2$ in the core region and ${\alpha}-Fe_2O_3$ in the shell region. In addition, the XPS results confirmed the formation of Fe-doped $TiO_2$ by the doping effect of $Fe^{3+}$ ions into the $TiO_2$ lattice, which can affect the ferromagnetic properties in the core region. For comparison, pure ${\alpha}-Fe_2O_3$ NWs were also fabricated using an electrospinning method. With regard to the magnetic properties, the Fe-doped $TiO_2/{\alpha}-Fe_2O_3$ core-shell NWs exhibited improved saturation magnetization(Ms) of approximately ~2.96 emu/g, which is approximately 6.1 times larger than that of pure ${\alpha}-Fe_2O_3$ NWs. The performance enhancement can be explained by three main mechanisms: the doping effect of Fe ions into the $TiO_2$ lattice, the size effect of the $Fe_2O3_$ nanoparticles, and the structural effect of the core-shell nanostructures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.59-65
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• 2006

The impermeable seed coat is valuable trait in soybean because impermeable seed retain viability for longer period than permeable seed under adverse conditions such as delayed harvest or prolonged storage. Soybean seeds of various size showing different seed hardness were examined for their water absorption and seed viability under adverse storage conditions. Of one hundred thirty nine genotypes, eight types of seeds having different seed hardness and seed size were used as material. Soybean genotypes showing high hard seed rate, GSI13125 (89%), GSI10715 (54%), and GSI10284 (42%), were slow in water absorption and low in the electroconductivity of seed leachate in distilled water. Germination of GSI10284 and GSI13125 that have higher hard seed rate was less affected by CSVT and artificial aging treatment indicating higher seed storability. The higher storing ability of both collections was confirmed by electroconductivity test for leachate. GSI10122 showed low seedling emergence when the seeds were artificially aged. This genotype was considered as to having a poor storing ability based on difference of electroconductivity before and after artificial aging. Among tests conducted in the experiment, CSVT could be used for determining storage life in legumes. In conclusion, water absorption property of seed was strongly related to the hardness that is directly related to the seed viability and storing ability in soybean seed.

• Journal of IKEEE
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• v.27 no.1
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• pp.25-29
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• 2023

Effect of the processes of polysilazane solid electrolyte layer and silver (Ag) active electrode on the electrical characteristics of memristor was investigated. The memristor with the solid electrolyte annealed at higher temperature exhibited the higher set voltage and better memory retention characteristics than that annealed at lower temperature. The increase in the set voltage and the improvement of the memory retention characteristic at high annealing temperature were attributed to a reduction in the void density and an increase in the void uniformity inside the solid electrolyte, respectively. In the case where the polysilazane solution's concentration is high, the memristor exhibited rapid degradation of low resistive state even annealed at high temperature. Lastly, it was shown that the memristor with the solution-processed Ag active electrode showed WORM property unlike that with the vacuum-processed Ag active electrode. The WORM property was possibly due to morphological defects present in the solution-processed Ag active electrode.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.53-60
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• 1993

Anaerobic bacteria are suggested to be potential source for new antibiotics. In order to search for antibiotics from domestic origin, we collected 800 soil samples across Korean locations and could isolate as many as 989 anaerobic strains. Among them 10, strains were found to have good producing capacity of antibiotics. An anaerobe was finally selected due to secreting antibiotics having high antimicrobial activity towards multiple resistant microorganism(E coli JM 83) transformed by genetic engineering technique. Its morphological, physiological and biochemical charateristics were investigated, together with antimicrobial spectrum therefrom. On antimicrobial spectrum study, substance secreted from this strain, had no activities to fungus and yeast. The selected strain showed G(+) and coccal shape, on Gram, staining and electron scanning microscopy, respectively. Biochemically this strain utilized glucose, fructose lactose, sucrose, but did not arabinose, cellulose, rhamnose, sorbitol, trehalose, mannitol. Catalase test showed negative property. Optimal growth temperature was $37^{\circ}C$. The results obtained above suggest this strain Streptococcus faecium subspp. and we named it Streptococcus sp. An-21-1.

• Natural Product Sciences
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• v.8 no.3
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• pp.83-89
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• 2002

Butea monosperma Kuntze, commonly known as 'Palash', is employed in various indigenous systems of medicine against several diseases and almost every part of the plant has diversified medicinal properties. The seeds are used as anthelmintic, aperient, digesti and to treat piles, skin diseases and abdominal troubles. They also have the property of reducing 'Kapha' and 'Vata' (in Ayurveda). In the present paper a detailed pharmacognostical evaluation of seeds has been undertaken. The study includes macro- and micro-scopical details, fluorescence powder study and HPTLC fingerprinting. The seed is characterized by finely ridged seed coat and palisade-like malpighian cells, discontinuous transparent linea lucida in upper half of malpighian layer and simple & oblong hilum. The study also concludes that the seed samples procured from different places have similar morphological and physico-chemical characteristics. These observations are also supported by similar TLC profiles. The estimation of heavy metals (to detect permissible toxic limits), and fatty acid composition have been carried out. An attempt has also been made to see the ecological and edaphic variations, if any.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.353-358
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• 1998

Experiments were performed to find out the physico-chemical properties of milt, and morphological changes of cryopreserved spermatozoa in tiger puffer, Takifugu rubripes. The average number of sperm and spermatocrit in milt stripped were $9.81{\pm}0.34{\times}10^{10}/m{\ell}$ and $97.8{\pm}0.8$, respectively. While total lipid concentration from seminal fluid was higher than that from sperm, total protein concentration from sperm was higher than that from seminal fluid, Na and K concentrations in sperm and those in seminal fluid were similar each other, However, glucose from sperm and seminal fluid were not detectable. Spermatozoon of tiger puffer was consisted of head, middle Piece and tail. Size of head showing horseshoe shape was $0.65{\pm}0.10{\mu}m$ in diameter and $1.35{\pm}0.30{\mu}m$ in length. The head fully containing chromatin did not have acrosome. Mitochondrion in middle piece was $0.2{\mu}m$ in average diameter and flagellum showed 9+2 structure. A few of cryopreserved spermatozoa showed morphologically loose or swollen plasma membranes.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.332-338
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• 2002

A strain YB-4 producing the extracellular $\alpha$-galactosidase was isolated from soil, and has been identified as Streptomyces sp. on the basis of its cultural, morphological and physiological properties. The partially purified $\alpha$-galactosidase was most active on paranitrophenyl-$\alpha$-D-galactopyranoside at pH 6.0 and 6$0^{\circ}C$. The enzyme retained 90% of its maximum activity between pH 4.0 and pH 10.0 after pre-incubation for 1 h. The enzyme was able to hydrolyze oligomeric substrates such as melibiose, raffinose and stachyose to liberate galactose residue, indicating that the $\alpha$-galactosidase of Steptomyces sp. YB-4 hydrolyzed $\alpha$-1,6 linkage.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.339-349
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• 2009

An attempt has been made to assess whether the dose dependent effect of benzene extract of Ocimum sanctum leaves on the morphological changes in the cauda epididymal spermatozoa and sperm parameters in male albino rats. Scanning Electron Microscope observations illustrate the disturbance in plasma membrane as well as acrosomal membrane. Most of the sperms appear morphologically abnormal in the mid region of the tail; there is formation of balloon like cytoplasmic droplet. Sperm parametric study exhibits decrease in the total sperm count, sperm motility, forward velocity and increase in the percentage of abnormal sperms in dose dependent manner on treatment benzene extract of Ocimum sanctum leaves. The results suggest that the effects may have resulted from a general disturbance in the proteins and alteration in cauda epididymal milieu probably due to androgen deficiency consequent upon antiandrogenic property of Ocimum sanctum leaves.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.240-248
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• 2016

Radish is a common vegetable consumed in Korea, Japan, and China. Radish Breeding has been conducted based on morphological properties, such as shape and color. Recently, physicochemical properties of radish are attracting more attention from breeders to develop cultivars for the retail market. In this study, major components of radish were determined and their relationship with textural property analyzed. Sixty-six radish cultivars were selected and divided into white head (WH) and green head (GH) according to their head color. The cutting forces of GH and WH groups were $2.17{\pm}0.34kg$ and $2.31{\pm}0.36kg$, respectively (P > 0.05). The starch contents of GH and WH were $3.75{\pm}0.39g\;per\;100g$ (dry basis) and $4.24{\pm}0.62g$, respectively. Cellulose contents in both groups were similar at 12.3-12.4 g per 100 g (dry basis). Pearson correlation coefficients between cutting force, cellulose content, and starch content ranged from -0.33-0.326 which does not demonstrate any strong correlation between these components. Therefore, no relationship was found between the cutting force and the starch content or the cellulose content for the cultivars analyzed in this study. As the first intensive study on the texture and the major components of radish, these results could provide valuable information for radish breeding if further studies on taste and nutrient components are conducted.