• Corrosion Science and Technology
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• v.11 no.1
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• pp.1-8
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• 2012

The development of martensitic grades which can be processed in continuous galvanizing lines requires the reduction of the oxides formed on the steel during the hot dip process. This reduction mechanism was investigated in detail by means of High Resolution Transmission Electron Microscopy (HR-TEM) of cross-sectional samples. Annealing of a martensitic steel in a 10% $H_2+N_2$ atmosphere with the dew point of $-35^{\circ}C$ resulted in the formation of a thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film and amorphous $_{a-X}MnO.SiO_{2}$ oxide particles on the surface. During the hot dip galvanizing in Zn-0.13%Al, the thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was reduced by the Al. The $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides however remained embedded in the Zn coating close to the steel/coating interface. No $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formation was observed. During hot dip galvanizing in Zn-0.20%Al, the $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was also reduced and the amorphous $_{a-X}MnO.SiO_{2}$ and $a-SiO_{2}$ particles were embedded in the $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formed at the steel/coating interface during hot dipping. The results clearly show that Al in the liquid Zn bath can reduce the crystalline $_{C-X}MnO.SiO_{2}$ (x>1) oxides but not the amorphous $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides. These oxides remain embedded in the Zn layer or in the inhibition layer, making it possible to apply a Zn or Zn-alloy coating on martensitic steel by hot dipping. The hot dipping process was also found to deteriorate the mechanical properties, independently of the Zn bath composition.

• Magazine of the Korea Concrete Institute
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• v.10 no.4
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• pp.153-161
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• 1998

Concrete structures has been deteriorated by and freezing the thawing due to temperature gap. This study was conducted to evaluate durability of concrete which are increasingly demanded recently. Therefore the research of durability must be executed for application of waste foundry sand concrete real structures. Concrete durability properties incorporating waste foundry sand was performed with the variable of W/C ratio. Sand/Waste foundry sand ratio and Air entrainment-Non air entrainment. Cylinder specimens were made and subjected to freezing and thawing cycle at -18$^{\circ}C$ and 4$^{\circ}C$. Dynamic modulus of elasticity were evaluated as F/T cycle increase. The results show that strength of concrete is increased the W/C ratio decrease, the Sand/Waste foundry sand ratio increases when the concrete contains AE agent and decreasing W/C ratio and AE concrete makes improved resistance of freezing and thawing improved. Especially, resistance of freezing and thawing is improved by Fine aggregate/Waste foundry sand ratio which is 50%, 25%, 0% in a row. Therefore it is turn out the waste foundry sand could be applied to concrete from the experiment.

• Korean Journal of Medicinal Crop Science
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• v.27 no.4
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• pp.284-291
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• 2019

Background: Ginseng root rot disease, caused by Cylindrocarpon destructans and Fusarium solani is a major cause of replant failure in continuous cropping ginseng. Methods and Results: To control replant injury in soil infected with C. destructans and F. solani, biosolarization was performed by covering the plot with transparent polyethylene film after adding green manure of maize and sunflower for the summer season. Per 10 a, fresh and dry weight of maize was 10.1 and 2.5 tons, respectively, and that of sunflower was 8.1 tons and 1.2 tons, respectively. Mean maximum temperature at 20 cm depth was $33.2^{\circ}C$, $41.5^{\circ}C$ and $41.8^{\circ}C$ in the control, maize-incorporated and sunflower-incorporated plots, respectively. The elapsed time over $40^{\circ}C$ was 36.4 h in the maize-incorporated plot and 77.3 h in the sunflower-incorporated plot. Biosolarization increased $NO_3$ content in soil, while content of organic matter, Ca, and Mg was decreased. Electrical conductivity, $NO_3$ and $P_2O_5$ in soil significantly increased after two years of biosolarization. The number of spores of C. destructans in soil was significantly decreased by biosolarization, and sunflower treatment was more effective than maize treatment in decreasing the number of spores. Root yield of 3-year-old ginseng was significantly increased by biosolarization, however, there was no significant difference between maize and sunflower treatments. Rate of root rot in 3-year-old ginseng decreased to 16.5% with the incorporation maize and 5.0% with the incorporation of sunflower, while that in control 25.6%. Conclusions: Biosolarization was effective in inhibiting ginseng root rot by decreasing the density of root rot disease and improving soil chemical properties.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1124-1134
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• 2017

Objective: This study explored the physico-chemical properties of late-incubation egg amniotic fluid and a potential in ovo feed (IOF) supplement. Methods: Amniotic fluid was collected from broiler breeders (Ross 308, 51 weeks and Cobb 500, 35 weeks) on day 17 after incubation. A mixture of high-quality soy protein supplement - Hamlet Protein AviStart (HPA) was serially diluted in MilliQ water to obtain solutions ranging from 150 to 9.375 mg/mL. The mixtures were heat-treated (0, 30, 60 minutes) in a waterbath ($80^{\circ}C$) and then centrifuged to obtain supernatants. The amniotic fluid and HPA supernatants were analysed for their physico-chemical properties. Results: Only viscosity and $K^+$ were significantly (p<0.05) different in both strains. Of all essential amino acids, leucine and lysine were in the highest concentration in both strains. The osmolality, viscosity and $pCO_2$ of the supernatants decreased (p<0.05) with decreasing HPA concentration. Heat treatment significantly (p<0.05) affected osmolality, pH, and $pCO_2$, of the supernatants. The interactions between HPA concentration and heat treatment were significant with regards to osmolality (p<0.01), pH (p<0.01), $pCO_2$ (p<0.05), glucose (p<0.05), lactate (p<0.01) and acid-base status (p<0.01) of HPA solutions. The $Ca^{2+}$, $K^+$, glucose, and lactate increased with increasing concentration of HPA solution. The protein content of HPA solutions decreased (p<0.05) with reduced HPA solution concentrations. The supernatant from 150 mg/mL HPA solution was richest in glutamic acid, aspartic acid, arginine and lysine. Amino acids concentrations were reduced (p<0.05) with each serial dilution but increased with longer heating. Conclusion: The values obtained in the primary solution (highest concentration) are close to the profiles of high-protein ingredients. This supplement, as a solution, hence, may be suitable for use as an IOF supplement and should be tested for this potential.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.1-31
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• 1981

Rootability of the hardwood cuttings of mulberry was related not only histological characteristics but dependent on biochemical properties. In this connection, the characteristics of the hardwood cuttings were histologically observed and the growth substances produced by the cuttings were also identified by means of mung bean bioassay. Amino acid, carbohydrate, nucleic acid contents, and the C/N ratio were also analysed. The results are summarized as follows. 1. There were differences in rootability of cuttings between mulberry species and varieties Among the three mulberry species tested, Morus Lhou Koidz. showed the highest rootability while M. bombycis showed the lowest one. In varietal differences in rootability, it was shown that the varieties could be grouped according to rootability: high varieties(above 80%), medium(41~79%), and low(below 40%). The higher varieties were Kemmochi, Nakamaki, Kosen, and Wusuba roso. 2. The histological characteristic of the hardwood cuttings most closely related to rootability was cell layer arrangement in the sclerenchyma tissue. The lower rootability varieties developed two or three overlapping cell layers in the bark tissue and in the higher rootability varieties they were scattered over the primary cortex. 3. In the higher rootability varieties, there was a positive correlation between the development of root primodia and rootability of the hardwood cuttings. It was also shown that there was a close relationship between the size of primodia and the surface area of the lenticel with rootability of the cuttings. 4. Effect of growth substances extracted from the hardwood cuttings were determined by mung bean bioassay. The higher rootability varieties usually showed higher activities of the growth substances, in contrast the lower rootability varieties showed higher activities of the inhibitory substances. 5. It was evident that the substance separated by paper chromatography was identified as indole acetic acid with $R_f$ value ranging from 0.3 to 0.5. The other substances detected at a $R_f$ value ranging from 0.8 to 1.0 and origin to 0.1 were also responsible for rooting. 6. There exists a quantitatively different distribution of growth substances in a synergistic system in the tissues of cuttings, and the balance between growth and inhibitory substances gives rise to the development of rooting. Particularly, no descent of the substances from winter buds resulted in no rooting of cuttings but these substances were produced a week after planting in a warm environment. 7. It was shown that there were positive correlations between carbohydrate ($r=0.72^*$) and total sugar ($r=0.67^*$) and rootability, respectively, but there were negative correlations between reducing sugars ($r=-0.75^*$) and rootability. 8. High C/N ratio gave rise to high rootability($r=0.67^*$). The latter therefore depended on high amount of carbohydrate rather than nitrogen in the cuttings. 9. The content of RNA and DNA in the cuttings was not changed for upto two weeks after the cuttings were planted. Then an increase in RNA content took place in only the high rootability varieties. 10. There were quantitative and qualitative differences in the compositions of the amino acids between the high rootability varieties and the low rootability varieties. More aspartic acid and cystine were found in the higher rootability varieties than in the low rootability varieties.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.13-44
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• 1982

1. Since long time ago, it has been talked about that soaking wood into water for a long time would be profitable for the decreasing of defects such as checking, cupping and bow due to the undue-shrinking and swelling. There are, however, no any actual data providing this fact definitly, although there are some guesses that water soluble extractives might effect on this problem. On the other hand, this is a few work which has been done about the effect of water soluble extractives upon the some physical properties of wood and that it might be related to the above mentioned problem. If man does account for that whether soaking wood into water for a long time would be profitable for the decreasing of defects due to the undue-shrinking and swelling in comparison with unsoaking wood or not, it may bring a great contribution on the reasonable uses of wood. To account for the effect of water soluble extractives upon physical properties of wood, this study has been made at the wood technology laboratory, School of Forestry, Yale university, under competent guidance of Dr. F. F. Wangaard, with the following three different species which had been provided at the same laboratory. 1. Pinus strobus 2. Quercus borealis 3. Hymenaea courbaril 2. The physical properties investigated in this study are as follows. a. Equilibrium moisture content at different relative humidity conditions. b. Shrinkage value from gre condition to different relative humidity conditions and oven dry condition. c. Swelling value from oven dry condition to different relative humidity conditions. d. Specific gravity 3. In order to investigate the effect of water soluble extractives upon physical properties of wood, the experiment has been carried out with two differently treated specimens, that is, one has been treated into water and the other into sugar solution, and with controlled specimens. 4. The quantity of water soluble extractives of each species and the group of chemical compounds in the extracted liquid from each species have shown in Table 36. Between species, there is some difference in quantity of extractives and group of chemical compounds. 5. In the case of equilibrium moisture contents at different relative humidity condition, (a) Except the desorption case at 80% R. H. C. (Relative Humidity Condition), there is a definite line between untreated specimens and treated specimens that is, untreated specimens hold water more than treated specimens at the same R.H.C. (b) The specimens treated into sugar solution have shown almost the same tendency in results compared with the untreated specimens. (c) Between species, there is no any definite relation in equilibrium moisture content each other, however E. M. C. in heartwood of pine is lesser than in sapwood. This might cause from the difference of wood anatomical structure. 6. In the case of shrinkage, (a) The shrinkage value of the treated specimen into water is more than that of the untreated specimens, except anyone case of heartwood of pine at 80% R. H. C. (b) The shrinkage value of treated specimens in the sugar solution is less than that of the others and has almost the same tendency to the untreated specimens. It would mean that the penetration of some sugar into the wood can decrease the shrinkage value of wood. (c) Between species, the shrinkage value of heartwood of pine is less than sapwood of the same, shrinkage value of oak is the largest, Hymenaea is lesser than oak and more than pine. (d) Directional difference of shrinkage value through all species can also see as other all kind of species previously tested. (e) There is a definite relation in between the difference of shrinkage value of treated and untreated specimens and amount of extractives, that is, increasing extractives gives increasing the difference of shrinkage value between treated and untreated specimens. 7. In the case of swelling, (a) The swelling value of treated specimens is greater than that of the untreated specimens through all cases. (b) In comparison with the tangential direction and radial direction, the swelling value of tangential direction is larger than that of radial direction in the same species. (c) Between species, the largest one in swelling values is oak and the smallest pine heartwood, there are also a tendency that species which shrink more swell also more and, on the contrary, species which shrink lesser swell also lesser than the others. 8. In the case of specific gravity, (a) The specific gravity of the treated specimens is larger than that of untreated specimens. This reversed value between treated and untreated specimens has been resulted from the volume of specimen of oven dry condition. (b) Between species, there are differences, that is, the specific gravity of Hymenaea is the largest one and the sapwood of pine is the smallest. 9. Through this investigation, it has been concluded that soaking wood into plain water before use without any special consideration may bring more hastful results than unsoaking for use of wood. However soaking wood into the some specially provided solutions such as salt water or inorganic matter may be dissolved in it, can be profitable for the decreasing shrinkage and swelling, checking, shaking and bow etc. if soaking wood into plain water might bring the decreasing defects, it might come from even shrinking and swelling through all dimension.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.275-282
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• 1986

A series of studies on the properties of clayey terrace soils distributed at the inland (Yeongcheon) and coastal (Yeongjil) regions in Yeongnam district was carried out. On the base of the facts found and already reported about the macro morphological features as well as on pedological characters in micro scale, physicochemical properties, mineralogical characteristics etc., the present study dealt with soil genesis and tried to classify the soils for reasonable use and managements. 1. Although the both regions belonged to "Mesic" soil temperature regime and "red and yellow earths" areas of "Thornthwaite" pedo-climatic diagram, climatic indices as a soil forming factor indicate that the coastal Yeongil had milder than the inland Yeongcheon. 2. All the terrace soils had developed soil profiles with an "Argrllic B". Upyeong soils in Yeongil region had "Argillans" even in the "II B horizons" that possibly be "Paleo-argillic". 3. The bisequum profiles of Bancheon in Yeongcheon and Upyeong in Yeongil revealed that they were developed on Late Mesozoic shale and on semiconsolidated Tertiary deposits respectively, therefore the overlying clayey terrace deposits were assumed to be originated from the Early Quaternary deposits, Diluvium. 4. To supplement the Soil Taxonomy of USDA, the terrace soils with different degrees of gleyzation were classified as follows; Deogpyeong and Hwadong soils which have less than 50cm of paddified gley horizons (redness less than 0.5) in the upper part of the profiles by artificial surface irrigation, tentatively classified into "Anthrepiaquic Hapludalfs" and the Geugrag soils that have more than 50cm of paddified gley horizons within 1.2m of the profiles, into "Anthr-aquic Ochraqualfs" while the Upyeong soils that had greyish mottles in subsoils by natural ground water remain as an "Aquic Hapludalfs" the same as present. The Bancheon soils with free mottles are into "Typic Hapludalfs" as used at present.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.328-334
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• 2014

This study reviewed the usability of sludge, a material that is additionally created when polysilicon (a solar light material) is produced, as the raw material for cement clinker. It was evaluated that when cement clinker is produced, the chloric component of polysilicon acted as a mineralizer in the firing process. In addition, the physical features of the produced cement were measured. The setting time of the produced cement was reduced as the amount of content of polysilicon sludge increased. Such results were drawn because the chloric component acted as hydration accelerator and enhanced the dissolution of calcium hydroxide that was formed by hydration of $C_3S$. Furthermore, for such reason, on the day 1, the compression strength of mortar increased as the content of polysilicon sludge increased. In day 3, 7, and 28, the tendency in which the compression strength increasing up to 5% of the amount of added polysilicon sludge was shown. It is because when clinker was produced, the chloric component increased the amount of $C_3S$ mineral created, thus enhancing the compression strength after day 3.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.126-130
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• 1989

In 14 kinds of ginsenosides in ginseng saponin, ginsenoside Rbr is contained the most abundantly. But ginsenoside Rd which is similar to ginsenoside R $b_1$in structure, was known to be superior to ginsenoside R $b_1$pharmaceutically. The convertible enzyme which can transform ginsenoside R $b_1$to Binsenoside Rd specifically among ginseng saponin, was purified homogeneously from Rhizopus japonicus. The optimal pH for the action of the enzyme was pH 4.8 to 5.0, and optimal temperature was 45$^{\circ}C$. The enzyme was stable in the range of pH 4.0 to 9.0, and the half activity of enzyme was remained by the thermal treatment at 6$0^{\circ}C$ for 2 hours. The enzyme activity was enhanced by addition of M $n^{++}$ or Fe, though inhibited by EDTA or o-phenanthroline. On the substrate specificity, the enzyme was. able to hydrolyze gentiobiose, cellobiose, amygdalin and prunasin, but not to hydrolyze any other kinds of Binsenosides besides Binsenoside R $b_1$. Km values of the enzyme for ginsenoside R $b_1$, gentiobiose and amygdalin were 5.0mM, 4.8mM and 3.7mM, respectively.3.7mM, respectively.y.

• Journal of the Korean Magnetics Society
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• v.9 no.1
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• pp.35-40
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• 1999

Sr substituted materials for some barium in M-type barium ferrite powder and Co-Ti substituted Sr-Ba hexagonal ferrite powder were prepared by citrate sol-gel method and 2 MOE sol-gel method these hexaferrite particles were reduced for 1hr in the hydrogen gas. The reduction temperatures were varied in the range of 250 $^{\circ}C$ to 500 $^{\circ}C$. X-ray diffraction patterns were measured using diffractometer with Cu $K_{\Alhpa}$ radiation. Mossbauer absorption spectra were measured with a constant acceleration spectrometer. We have focused on studying the origin of increasing $M_s$ by M$\"{o}$ssbauer spectroscopy. Ferrite particles which were sintered at 105$0^{\circ}C$ were found to be typical magnetoplumbite structure and single phase. XRD patterns with varying the reduction temperatures in $Sr_{0.5}Ba_{0.5}Fe_{10}O_{19}$ indicates ferrites particles become composite hexaferrites containing $\alpha$-Fe at T_{red}=350 \;$^{\circ}C$$. On the otherhand, it was found that $Co^{2+}$ ions and $Ti^{4+}$ ions in $Sr_{0.7}Ba_{0.3}Fe_{10}CoTiO_{19}$ prevent from changing $Fe^{3+}$ ions to $\alpha$-Fe during the $H_2$ reduction. Comparing Mossbauer results with XRD results, we have determined most of $\alpha$-Fe are reduced from $4f_{vi}$ sites and 12k sites of $Fe^{3+}$ ions. These $\alpha$-Fe phase bring the induced anisotropy and increase saturation magnetization $M_s$.TEX>.