• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.143-148
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• 2018

Sodium silicate based silica aerogels are lower in cost than silica alkoxide based silica aerogels, but the demand is decreasing as their physical properties are lowered. In this research, acetonitrile as a drying control chemical additive (DCCA) is added in the sol state to improve the pore-structural properties of sodium silicate based silica aerogel by preventing the agglomeration of particles and cross-linked bond. The sodium silicate based silica aerogel by ambient pressure drying were prepared by sol-gel process. Acetonitrile/$Na_2SiO_3$ molar ratio of 0, 0.05, 0.1, 0.15, and 0.2 was added to the sol state. The physical properties of the final product were analyzed using Fourier transform infrared, contact angle measurement, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda measurements and field emission scanning electron microscopy. It was confirmed that the sample with adding 0.15 molar ratio of acetonitrile and sodium silicate showed a high specific surface area ($577m^2/g$), a high pore volume (3.29 cc/g), and a high porosity (93%) comparable to the pore-structural properties of silica alkoxide based silica aerogels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.1
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• pp.57-66
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• 2013

The purpose of this study was to investigate the effects of shifts in sowing time on the ecological responses, growth and yields of major soybean cultivars in a southern region of South Korea. Experiments were carried out in Naju, Jeonnam Province (latitude $35^{\circ}$ 04'N, longitude $126^{\circ}$ 54'E) for three years from 2008 to 2010. The test cultivars included Saeol-kong and Tawon-kong of the summer type, Taekwang-kong and Pungsannamul-kong, and Cheongja3 of the autumn type. Sowing took place on May 15 and 30, June 15 and 30, and July 15 of each year. Of the summer type soybean cultivars, Saeol-kong showed a smaller curtailment in days from sowing to flowering, days from flowering to maturity, and days from sowing to maturity according to sowing time postponement than Tawon-kong. Of the autumn type soybean cultivars, Taekwang-kong exhibited a lower photoperiodic response in reproductive growth period than Pungsannamul-kong and Cheongja3, both of which recorded higher level photoperiodic responses in vegetative growth stages and reproductive growth periods than other test cultivars, with the former exhibiting higher levels than the latter. Most of the test cultivars tended to decrease in stem length, node numbers of the main stem, and stem diameter according to postponed sowing time, but there were no significant differences in stem length and node numbers of the main stem of the Saeol-kong cultivar. Differences in sowing times did not affect the first setting pod node order of Saeol-kong and Tawon-kong summer type cultivars of internode lengths of all of the test cultivars. All of the test cultivars tended to show decreases in pod number per plant due to postponement of sowing time except for the Saeol-kong cultivar. The variation was more prominent in small grain cultivars such as Tawon-kong and Pungsannamul-kong with the latter autumn type cultivar showing especially large variation. Yields were the greatest for the Tawon-kong, Taekwang-kong, and Pungsannamul-kong cultivars sown on May 30 and Cheongja3 sown on May 30 and June 15. There were no significant differences in the yields of Saeol-kong for different sowing times from May 30 to July 15, with the yields lowest for the batch sown on May 15.

• Korean journal of applied entomology
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• v.12 no.1
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• pp.1-21
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• 1973

Some experiments were conducted to investigate the effects of the chemosterilant, hempa, on the biology of the rice weevil, Sitophilus oryzae L., and the transmission of the lethal factors in the progeny. One to three days old adult males were fed on the wheat grains treated with concentrations of 0.0625, 0.125, 0.25, and $0.5\%$ of hempa water solution. The effects of the treatment on the mortality, longevity, and the performance of oviposition were examined for the Pl generation, and the hatchability and mortality in the postembryonic development were also tested in the $F_1,\;F_2,\;BC_1,\;F_3,\;and\;BC_2$ generations to analyze the inheritance of the lethal factors. The results obtained were summarized as follows. (1) The average longevity of the treated males were ranged from 26.6 to 30.4 days, and indicated no statistical differences. (2) The mortality of the treated males were ranged between $3.3\%\;and\;13.3\%$ and showed no statistical significance. (3) The overall mean number of eggs laid by a female mated to a treated male with concentrations of 0.0625, 0.125, 0.26 and $0.5\%$ were 3.78, 4.05, 3.75 and 3.61 for the respective treatments, and they were not differ significantly from those of control which were 3.60 per female per 3 day period. The unmated female laid 1.91 in the same period, and significantly differ from those in other experimental groups. (4) The overall mean hatchability of the eggs laid by the females mated with males that had been treated with various concentrations of hempa were 86.82, 64.77, 53.47, 40.33 and $24.78\%$ for the respective concentrations of 0, 0.0625, 0.125, 0.25 and $0.5\%$. The hatchability decreased with the increasing concentrations. (5) The minimum hatchabilities were obtained from the eggs laid in the period of 10-12 days after treatment, then the hatchability increased showing some recovery. The recovery seemed to be very much delayed for the males which had been treated with the greater concentrations. Such a difference in hatchability might be related with the sensitivity of the developmental stages of the sperms, and broader spectrum in the stages and severer effects seemed to be associated with the increased concentrations. (6) The overall mean of larval mortality in the $F_l$ generation were 6.55, 17.89, 27.40, 35.42 and $52.17\%$ for the respective concentrations of 0,0.0625, 0.125,0.25 and $0.5\%$. And there was a tendency to increase in the mortality with the increase of concentrations. (7) The correlation coefficients between per cent sterile eggs and larval mortality for the experimental plots of 0.125, 0.25 and $0.5\%$ treatments showed r=+0.83 and +0.85, respectively, and it seemed to be close correlation between the lethal effects on the embryonic and post-embryonic developments. (8) Since the $SC_{50}$ of the sterile eggs was $0.133\%$ and $SC_{50}$ of the larval mortality was $0.565\%$, it was considered that tile lethal factors expressed more in the egg stages than the larval stages. (9) The ratio of female to male in the $F_l$ adults showed 100 : 125, 100 : 108 and 100 : 124 for the plots of 0.125, 0.25 and $0.5\%$ treatments, respectively. And it n·as considered that the sex ratio distortions might occur with the higher concentrations. (10) When the F, males originated 1.on the eggs had been laid by p, in the period of 16-18 days after treatment, were crossed to normal females $(BC_1)$ and made sib matings $(F_2)$, the per cent sterile eggs of the $BC_1$ generation were 13.88 and $33.04\%$ , and were 31.01 and $38.73\%$ for the $F_2$generation with the plots of 0.0625 and $0.125\%$ treatment, respectively. And these seemed to be a results of the $F_1$ individuals are carrying some chromosomal aberrations (11) The larval mortality was the highest in the $F_2$ plot and followed the female backcross plot, and the least in the male backcrosses. (12) The proportions of 1st and 2nd instar larvae among the larval development at tile 17th day after oviposition were 10.98, 27.26, 32.98 and $15.73\%$ in the normal female $\times$ normal male, $F_1$ female$\times$normal male, normal $female \;\times F_1$ male and $female \;\times F_1$ male plots, respectively. It was considered that the larval development might be delayed by the treatment in the 2nd generation. (13) Per cent larval mortality and sterile eggs were greater in the $F_2$ sib mating plots $(F_3)$ than both of $F_2$ backcrosses. Therefore, it seemed that some of the recessive lethal mutations might affect in the further generations. (14) The sterility, induced by the treatment of chemosterilant, hempa, was considered as the result of the dominant lethal mutations due to chromosomal aberrations such as translocation and/or deletion. The effects of these lethal factors seemed to be inherited tip to 3rd generation after treatment.

• KSBB Journal
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• v.18 no.3
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• pp.211-216
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• 2003

The removal yield of dissolved organic matter in drinking water by biological activated carbon (BAC) process was investigated. The tested processes wer raw water-AC process (BAC1), raw water-ozonation-BAC process (BAC2), and raw water-ozonation-coagulation/sedimentation-BAC process (BAC3). The amounts of organic matter was measured as dissolved organic carbon (DOC), ulta-violet radiation at 254 nm wavelength ($UV_{254}$), total nitrogen (T-N), ammonia nitrogen (NH_3$-N), and total phosphate (T-P). As a results, 30.7% DOC was removed by BAC2 process, which showed higher removal efficiency than BAC1 or BAC3 processes. The removal yield of $UV_{254}$ in BAC1, BAC2, and BAC3 processes were observed as 45.3%, 44.6%, 58.4%, respectively. And the removal yield of ammonia nitrogen were 66%, 81%, 29% in each BAC processes. The optimal empty bed contact time (EBCT) of BAC processes was estimated as 10 minute. This study has shown that BAC process combined with ozone treatment was efficient for removing dissolved organic matter in water.

• Food Science of Animal Resources
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• v.24 no.3
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• pp.283-292
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• 2004

This study was conducted to investigate feeding effects of the high pressure boiled extracts (HPBE) of the Ogol chicken with herbs on glucose, hormones and immunological response (cytokine, specific antibody) of serum in the rat which fed either with normal feed (T$_1$), normal feed + herb HPBE (T$_2$), normal feed + Ogol chicken HPBE (T$_3$), normal feed + mixture of cross-bred Ogol chicken HPBE (T$_4$) hydrolyzed with Flavourzyme 0.1% for 35 days. During experimental period, there was a weak trend to have a higher glucose content for the T$_4$ group with 102.27${\pm}$5.95 mg/dL, but it was not significantly higher than other treatments. For insulin level, T$_1$ group showed numerically a slightly higher level with 6.79${\pm}$4.64 ${\mu}$IU/mL, but the difference was not significant in statistic term due likely to a large variation in comparison with other treatments. The treatments did not significantly alter testosterone level in rat plasma with 1.09, 1.46, 0.98, 1.13 ng/mL in T$_1$, T$_2$, T$_3$ and T$_4$, respectively. T$_4$ treatment increased the aldosterone level to a significantly (p<0.05) higher level (273.33 ng/dL) than other treatments. The extract treated rat showed a tendency in the cortisol level of lower levels than the control group, particularly, it was significantly (p<0.05) lower in T$_3$ group than other groups. T$_3$ and T$_4$ groups showed higher levels for interlukin-4 (IL-4) and anti-BSA IgG in immune cells and plasma. T$_2$, T$_3$ and T$_4$ treatments showed a slightly higher levels in v-interferon (INF-r) than the control, with a greater effect for T4 treatments. These results suggested that HPBE of the cross-bred Ogol chicken hydrolyzed with Flavourzyme increased immunological activity and decreased the concentration of cortisol and aldosterone hormones.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.258-265
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• 2009

An anionic polyurethane dispersions (PUDs) were synthesized from the poly (tetramethylene glycol) (PTMG, Mw = 2000 g/mol), mixed isocyanate of dicyclohexylmethane-4,4'-diisocyanate $(H_{12}-MDI)$ and 4,4'-diphenylmethane diisocyanate (MDI), and dimethylol propionic acid (DMPA) as anionic site, following a prepolymer mixing process. Triethylamine (TEA) was used as a neutralization agent and the ethylenediamine (EDA) as the chain extender of the prepolymer. The effects of the DMPA molar ratio and aromatic diisocyanate content in the mixed isocyanate on the particle size and viscosity of PUD were studied. Also, the mechanical and thermal properties of the PUD cast films were discussed according to the molar ratio of DMPA and aromatic isocyanate content. It was found that the particle size and the viscosity of an anionic PUD decreased with increasing DMPA molar ratio but increased with increasing aromatic isocyanate (MDI) content in the mixed isocyanate at the constant DMPA content. Tensile strength of the PUD cast films increased and elongation at break decreased with increasing DMPA content at the constant mixed isocyanate molar ratios. In thermal degradation temperature of PUD cast films, the effect of DMPA contents was great but the effect of aromatic isocyanate contents at the low DMPA content was very slight respectively.

• Membrane Journal
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• v.23 no.6
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• pp.450-459
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• 2013

2,3,5,6-Tetramethyl-1,4-phenylenediamine (TMPD) based polyimide (PI) were crosslinked with 1,2-Diaminoethane (DAE) and 1,6-Diaminohexane (DAH) to enhance gas transport properties. Fourier transform infrared (FT-IR) studies show that imide groups were converted into amide groups during crosslinking process. Thermogravimetric analysis (TGA) results indicate that the degradation temperature of crosslinked PI membranes decreased after crosslinking. This is due to degradation of alkyl group in crosslinking agent. The d-space of crosslinked PI membranes decreased with increasing crosslinking time. The ideal permeability for $CH_4$, $N_2$, $O_2$, and $CO_2$ decreased after crosslinking and the ideal permeability of crosslinked PI membranes induced by DAH is larger than that by DAE. In contrast, the permselectivity of $CO_2/CH_4$, $CO_2/N_2$ and $O_2/N_2$ increased during crosslinking. For the gas pair of $CO_2/CH_4$, the maximum increment is about 39.5% after 6 minutes of DAE crosslinking. Also, that of $O_2/N_2$ gas pair is about 20.5% after 6 minutes of DAE crosslinking. According to these result, DAE is more suitable for enhanced permselectivity than DAH. On the contrary, DAE is not useful for $CO_2/N_2$ separation due to reduction in $CO_2/N_2$ permselectivity after 3 minutes DAE crosslinking.

• Journal of Life Science
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• v.28 no.7
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• pp.849-856
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• 2018

Diarrhea is one of the main disorders which cause the highest level mortality of the post-weaning economic animal. Beech-wood creosote has been used as a traditional anti-diarrheic medicament for a long time. The present study was conducted to investigate the effects of dietary supplementation of Beech-wood on growth performance and intestinal microbiota in rats. Twelve 4-week-old rats were randomly assigned to one of four dietary groups and fed a basal diet supplemented with none (CON), 0.5% apramycin (ANTI), 0.4% creosote (Creo 0.4), or 0.8% creosote (Creo 0.8) for 4 weeks following 1 week of adaptation period to the respective diet. Average daily gain was not influenced by the dietary treatment whereas average daily feed intake was greatest for the Creo 0.8 group. In the intestinal microbiota at the level of the phylum, the percentage of Firmicutes bacteria decreased but Bacteroidetes increased in the Creo 0.8 group vs. Control, which resulted in a decreased F/B ratio for the former (p<0.05). Moreover, the percentage of Lachnospiraceae was greater at the level of the family for the Creo 0.8 group than for Control, but the percentages of Turicibacter and Clostridium disporicum were less in the former (p<0.01) at the genus and species levels, respectively. Collectively, the present results indicate that dietary supplementation of creosote increases the feed intake and also influence the intestinal microbiota in rats.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.351-355
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• 1999

In order to find anti-dementia drugs from natural products, prolyl endopeptidase inhibitors were purified from Puerariae Flos by consecutive solvent partition, followed by silica gel, Sephadex LH-20, and HPLC. Four isoflavonoid inhibitors were isolated and identified as tectorigenin, genistein, 5,7-dihydroxy-4',6-dimethoxyisoflavone, and 5-hydroxy-6,7,4'-trimethoxyisoflavone by means of instrumental analyses including $^{1}H-$, $^{13}C-$, $^{2}D-NMR$ and MS and $IC_{50}$ values against PEP were 5.30 ppm$(17.7\;{\mu}M)$, 10.39 ppm$(38.5\;{\mu}M)$, 13.92 ppm$(44.3\;{\mu}M)$, and 20.61 ppm$(62.8\;{\mu}M)$, respectively. Some previous mistakes in $^{13}C-NMR$ assignment were revised by careful investigation of HMBC and HMQC data.

• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.109-113
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• 2011

Crystallization of calcium carbonate were performed by adding aspartic acid and lysine into $CaCl_2$ solution for understanding biomineralization in gas-liquid reaction of $NH_4HCO_3$ and $CaCl_2$. Proportion between calcite and vaterite of calcium carbonate crystals was identified by changing conditions such as reaction time, addition amount of aspartic acid, lysine, $CaCl_2$, and $NH_4HCO_3$. FT-IR(Fourier Transform Infrared spectroscopy) instrument was used to perform analysis of vaterite ratio. Under the condition of $NH_4HCO_3$ 10 g and no additive, an increase of vaterite crystal changed to a decrease around 0.15 M $CaCl_2$. Then it largely increased at 0.25 M $CaCl_2$, after vaterite proportion was rising again at 0.20 M $CaCl_2$. In contrast to that, vaterite crystal continuously decreased to 0.2 M $CaCl_2$, and increased from 0.25 M $CaCl_2$ with 20 g $NH_4HCO_3$. Vaterite crystals were observed to be a maximum after 2days with lysine addition, but $CaCO_3$ vaterite crystals showed minimum with aspartic acid.