• Weed & Turfgrass Science
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• v.2 no.2
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• pp.176-183
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• 2013

To explore hydrolysis methods for the efficient manufacture of sugar solutions from the freshwater alga Water-net (Hydrodictyon reticulatum, HR), acid hydrolysis, enzymatic hydrolysis, and combined hydrolysis (acid followed by enzymatic hydrolysis) were investigated. In the one-step acid hydrolysis, the reaction of 8% solids content using 2% sulfuric acid at $120^{\circ}C$ for 1 hour was desirable. In this case, glucose 27.44 g 100 g $DM^{-1}$ could be obtained from the HR-d13 samples. In the two-step acid hydrolysis, the primary hydrolysis (HR powder : 72% sulfuric acid = 1 g : 1.5 mL) was carried out for 1 hour at $60^{\circ}C$, and then the secondary hydrolysis was done for 1 hour at $120^{\circ}C$ after addition of distilled water 23.5 mL. In this case, glucose 35.11 g/100 g DM could be obtained from the HR-d13 samples. In the combined hydrolysis, 25% solids content using 2% hydrochloric acid were reacted for 1 hour at $120^{\circ}C$, and then citrate buffer and hydrolysis enzyme complexes (E1 1.0 mL+E2 0.2 mL $g^{-1}$ dried matter) were added and reacted for 1 - 2 days at $50^{\circ}C$. In this case, glucose 33.5 g 100 g $DM^{-1}$ could be obtained from the HR-d23+26 samples. In conclusion, combined hydrolysis was likely to be more useful saccharification method of HR biomass at a practical level, considering the glucose productivity, generation of fermentation-inhibiting substances (hydroxyl methyl furfural, furfural), and limited use of strong acid.

• Clean Technology
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• v.27 no.4
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• pp.359-366
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• 2021

Halloysite nanotubes (HNTs), the multiwalled clay mineral with the composition of Al₂Si₂O₅(OH)₄·nH₂O, have been highlighted as a low-cost adsorbent for the removal of dyes from wastewater. Although a powder of halloysite presents a high specific surface area, forming media are significantly considered due to sludge-clogging induced by the water-bound agglomeration. However, higher firing temperature to achieve the structural durability of the media and lower utilization rate due to longer penetration depth into the media act as hurdles to increase the dye-adsorption capacity. In this work, the retention of the adsorption capacity of halloysite was evaluated with methylene blue solution after the heat treatment at 750 ℃. In order to improve the utilization rate, tubular media were fabricated by extrusion. The images taken by transmission electron microscopy show that HNTs present excellent structural stability under heat treatment. The HNTs also provide superb capacity retention for MB adsorption (93%, 18.5 mg g^-1), while the diatomite and Magnesol^® XL show 22% (7.65 mg g^-1) and 6% (11.7 mg g^-1), respectively. Additionally, compositing with lignin enhances adsorption capacity, and the heat treatment under the hydrogen atmosphere accelerates the adsorption in the early stage. Compared to the rod-type, the tubular halloysite media rapidly increases methylene blue adsorption capacity.

• Applied Microscopy
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• v.39 no.2
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• pp.133-139
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• 2009

A officinal mushroom, Phellinus linteus (PL) has been known to exhibit potent biological activities including antioxidative and anticancer effect. PL is consumed as a type of powder or extract for the purpose of health promotion and disease treatment. Recently superfine PL products was commercialized according to the development of pulverizing technology such as nanomill, so the evaluation of food safety is suggested. This study was conducted to evaluate the food safety of superfine PL (SPL) through hematological, biochemical and histological examination in mice as compared with fine PL (FPL). In the particle size distribution in volume after nanomill processing, the mean diameter of SPL and FPL particles was 11.78 ${\mu}m$ and 216.1 ${\mu}m$, and d (0.5), the particle diameter measured at 50% of distribution was 5.5 ${\mu}m$ and 147.9 ${\mu}m$, respectively. As the result of body weight, food intake and the weight of organs, SPL group didn't show any statistical difference compared with FPL group and normal group (N). Hematological and biochemical values were also involved in the normal range, although ALT (N vs. FPL, P<0.001) and BUN (N vs. FPL, P<0.01; N vs. SPL, P<0.01) showed significance compared with N group but there are no significance between FPL and SPL group. In the result of histological examination with liver, kidney, spleen, and small and large intestine, abnormal findings such as inflammatory reaction and histological changes were not observed. Our results suggest that the oral intake of SPL diet is not harmful to the animal in the hematological, biochemical and histological aspects although particle size was reduced to the level of superfine. However, further study will be necessary to confirm the histological safety in relation to the gastrointestinal contact of superfine particles in the case of large amount and long-term intake.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.205-212
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• 1979

Red pepper paste were prepared by using various raw materials such as rice, glutinous rice, polished barley, polished wheat and corn powder, and their chemical compositions including reducing sugar, amino-N and ethanol were analyzed during the period of aging in order to elucidate effects of these starchy materials on the compositions and qualities of the products. The results obtained are summarized as follows: 1) Koji of these materials were manufactured respectively by inoculating a strain of Asporyzae and their activities of protease and saccharifying amylase were determined. Wheat koji was found to have the highest level of protease activity among the koji, while glutinous rice koji had the strongest amylase activity. 2) Contents of moisture, crude protein, crude fat, and sodium chloride in the red pepper pastes were not changed significantly, however total sugar content was decreased during the period of aging. 3) After 60 days of aging, the highest amount (160mg%) amino nitrogen was detected in the red pepper paste of polished wheat, but higher levels of reducing sugar and ethanol contents were detected in that of glutinous rice. 4) Amino acids in the products were analyzed after 60 days of aging: a) Total 17 amino acids were detected. b) Free amino acid ratio to total amino acid content was approximately 35 percent in average. c) Free glutamic acid was higher than any other free amino acid In the amount and free ratio, but free methionine was lower. d) Lysine content was relatively high, while histidine and glycine were detected in trace. 5) Sensory tests including color, odor and taste on the products resulted in the highest mark for the red pepper paste of glutinous rice but in the lowest mark for that of corn powder.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.5
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• pp.216-221
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• 2006

An investigation of the influence of $WO_3$ and $V_2O_5$ catalysts on the microstructure, phase formation and selective catalytic reduction (SCR) efficiency of the synthesized SCR powders has been carried out. A commercial anatase-$TiO_2$ was used as the catalysts support. For $WO_3(10wt%)/TiO_2$, the W loading to the $TiO_2$ support led to the lower in anatase to rutile transition temperature from $1200^{\circ}C$ of $TiO_2$ support to ${\sim}900^{\circ}C$. The transition temperature was also lowered to below $650^{\circ}C$ in the $V_2O_5$(5 and 10 wt%) added composition. The $WO_3(10wt%)/TiO_2$ SCR powder obtained at $450^{\circ}C$ showed near 100% of $NO_x$ conversion efficiency at $350{\sim}400^{\circ}C$ and for the powder prepared at $650^{\circ}C$ the same efficiency was achieved in wider temperature range $300{\sim}400^{\circ}C$. The highest $NO_x$ conversion efficiency of 100% was obtained in the $V_2O_5(5wt%)/TiO_2$ SCR composition calcined at $650^{\circ}C$ in the relatively wider temperature range $250{\sim}350^{\circ}C$, while the catalytic efficiency considerably decreased for the $V_2O_5(10wt%)/TiO_2$. The lowered conversion efficiency of $NO_x$ observed in the $V_2O_5(10wt%)/TiO_2$ composition calcined at $650^{\circ}C$ was considered to be correlated with the lowered surface area resulting from the increased crystallite growth by highly reactive vanadium loading.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.758-763
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• 1999

The protective effects of sea tangle (Laminaria japonica) extract and fucoidan components on the attack of oxygen radicals in kidney were studied, Sprague-Dawley (SD) male rats (210 $\pm$ 5 g) were with fed experimental diets of Dasi-Ex group (sea tangle extract powder of $4.0\%$ added to control diet), Euco-I, II and III groups (fucoidan powder of 1, 2 and $3\%$, respectively, added to Dasi-Ex group) for 45 days, Hydroxyl radical formations were significantly decreased ($10\~15\%$ and $15\~30\%$) in mitochondria and microsomes of Dasi-Ex and Fuco-I, II, III groups compared with control group. Hydrogen peroxide formations were also significantly decreased ($10\~15\%$) in microsomes of Dasi-Ex and Fuco-I, II, III groups compared with control group. Significant differences in mitochondrial basal oxygen radical (BOR) and microsomal induced oxygen radical (IOR) formations of Dasi-Ex and Fuco-I groups could not be obtained, but mitochondrial BOR and microsomal IOR formations were significantly decreased ($12\~15\%$ and $13\~14\%$) in Fuco-II and III groups compared with control group. BOR formations were significantly decreased ($12\~25\%$) in microsomes of Dasi-Ex and Fuco-I, II, III groups, and IOR formations were also significantly decreased ($10\~15\%$) in mitochondria of Fuco-I, II, III groups compared with control group, Significant differences in mitochondrial Mn-SOD activities of Dasi-Ex group could not be obtained, but mitochondrial Mn-SOD activities were dose-dependently increased by $8\%,\;16\%$ and $36\%$ in Fuco-I, II and III groups compared with control group, Mn-SOD activities an microsome were significantly increased about $20\%$ in Dasi-Ex group, while they were remarkably increased about $40\%$ in Fuco-I, II and III groups compared with control group. lipid peroxide contents were significantly decreased about $15\%$ and $15\~25\%$ in mitochondria and microsomes of Fuco-II and III groups. Membrane fluidities resulted in marked increases ($20\~35\%$ and $17\~24\%$) in mitochondria and microsomes of Dasi-Ex and Fuco-I, II and III groups. These results suggest that administrations of fucoidan added to sea tangle may play a pivotal role in attenuating attack of oxygen radicals in kidney.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.2
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• pp.55-65
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• 2003

The combined effect of bioaugmentation of dechlorinating bacterial cultures and addition of iron powder($Fe^0$ on reductive dechlorination of tetrachloroethylene(PCE) and other chlorinated ethylenes in a artificially contaminated soil slurry(60micromoles PCE/kg soil). Two different anaerobic bacterial cultures, a pure bacterial culture of Desulfitobacterium sp. strain Y-51 capable of dechlorinating PCE to cis-1,2-dechloroethylene(cis-DCE) and the other enrichment culture PE-1 capable of dechlorinating PCE completely to ethylene, were used for the bioaugmentation test. Both treatments introduced with the strain Y-51 and PE-1 culture (3mg dry cell weight/kg soil) showed conversion of PCE to cis-DCE within 40days. The treatments added with $Fe^0$(0.1-1.0%) alone to the soil slurry resulted in extended PCE dechlorination to ethylene and ethane and the dechlorination rate depended on the amount of $Fe^0$ added. The combined use of the bacterial cultures with $Fe^0$(0.1-1.0%)) showed the higher PCE dechlorination rate than the separated application and the pattern of PCE dechlorination and end-product formation was different from those of the separated application. When 0.1% of $Fe^0$ was added with the cultures, the treatments with the strain Y-51 and $Fe^0$ resulted in cis-DCE accumulation from PCE dechlorination, but the treatment with the enrichment culture and $Fe^0$ showed the more extended dechlorination via cis-DCE. These results suggested that the combined application of and the bactrial culture, specially the complete dechlorinating enrichment culture, is practically effective for bioremediation of PCE contaminated soil.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1078-1086
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• 1996

The peroxo-polytungstic acid was formed by the direct reaction of tungsten powder with the hydrogen peroxide solution. Peroxo-polytungstic powder were prepared by rotary evaporator using the fabricated on to ITO coated glass as substrate by dip-coating method using $2g/10mL(W-IPA/H_2O)$ sol solution. A substrate was dipped into the sol solution and after a meniscus had settled, the substrate was withdrawn at a constant rate of the 3mm/sec. Thicker layer could be built up by repeated dipping/post-treatment 15 times cycles. The layers dried at the temperature of $65{\sim}70^{\circ}C$ during the withdrawn process, and then tungsten oxides thin film was formed by final heating treatment at the temperature of $230{\sim}240^{\circ}C$ for 30min. A linear rotation between the thickness of thin film and the number of dipping/post-treatment cycles for tungsten oxides thin films made by dip-coating was found. The thickness of thin film had $60{\AA}$ after one dipping. From the patterns of XRD, the structure of tungsten oxides thin film identified as amorphous one and from the photographs of SEM, the defects and the moderate cracks were observed on the tungsten oxides thin film, but the homogeneous surface of thin films were mostly appeared. The electrochemical characteristic of the $ITO/WO_3$ thin film electrode were confirmed by the cyclic voltammetry and the cathodic Tafel polaization method. The coloring bleaching processes were clearly repeated up to several hundreds cycles by multiple cyclic voltammetry, but the dissolved phenomenon of thin film revealed in $H_2SO_4$ solution was observed due to the decrease of the current densities. The diffusion coefficient was calculated from irreversible Randles-Sevick equation from the data obtained by the cyclic voltammetry with various scan rates.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1034-1042
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• 1996

Various $TiO_2-SiO_2$ composite powders were prepared by the modified sol-gel method using 1-dodecanol as DCCA (Dryng Control Chemical Additive ). Their characterizations were carried out and their photocatalytic catalysis was examined on the evolution reaction of hydrogen. The weight losses at $500^{\circ}C$ of only $TiO_2$ and $SiO_2$ powders were 33. 0wt% and 42.5wt%, respectively, and those of the $TiO_2/SiO_2$ powders ($TiO_2/SiO_2=25/75$, 50/50 and 75/25) were about $70.0{\pm}3.0wt%$. The released substances from the powders were almost organic matters. The as-prepared powders except only $TiO_2$ powder were amorphous. Transformation of anatase to rutil was hindered by $SiO_2$ component and the crystallinity of anatase was decreased with increasing $SiO_2$ contents. The as-prepared powders were bulky states. By heating at $600^{\circ}C$ for 1 hr $TiO_2-SiO_2$ powders ($TiO_2=100%$, $TiO_2/SiO_2=75/25,\;50/50$) showed agglomerates consisted of particles in submicron, but those of $TiO_2/SiO_2=25/75$ and $SiO_2=100%$ were still bulky states. Specific surface area of the powders heat-treated at $600^{\circ}C$ for 1hr was increased with $SiO_2$ concents and their pore sizes were also depended on $SiO_2$ contents. The photocatalytic activity of $TiO_2/SiO_2=75/25$ heat-treated at $600^{\circ}C$ for 1hr was 0.240mo1/h.g-cat as $H_2$ evolution rate. This value was about 2.0 times that of P-25(Degussa P-25) as a standard photocatalyst.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.852-857
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• 2010

This study was performed to explore the effect of the clay mineral illite on the improvement of bed soil and plant growth. Red pepper (Capsicum annuum L.) was used as a model vegetable crop. The experiment was performed during the whole six weeks in the glass house of the Chungbuk National University. Its seedlings were cultivated in the bed soil normally used for horticultural purpose. Of the seedlings cultured, the healthy and regular size of seed were selected and cultivated in the pots. They were treated with two forms of illite, particulate (PA) and powder (PW), at the following application rates: standard application[P1 (PA1, PW1), 1:20 (w/w)], two times[P2 (PA2, PW2), 1:10 (w/w)], and four times[P4 (PA4, PW4), 1:5 (w/w)] of standard application. Untreatment (P0) was used as a control pot. At six weeks of cultivation, their growth lengths were correspondingly increased as the application rate was increased ranging from P0, P1, P2, and to P4. Their growth length was a little greater on the application of powder illite (PW) than on the particulate illite (PA). Based on the plant analysis for the root, leaf, stem of red pepper, the uptake amounts of K, Ca, and Mg, were correspondingly increased, as the application rate was increased ranging from P0, P1, P2, and to P4, respectively. At the same application rate, their amounts taken up in the respective parts were higher on the application of PW illite than on the PA one. Especially the amounts of Ca and Mg were higher in the stem, leaf than root. Consequently, it appears that the illite treatment, especially, PW form of illite, enhance the growth of red pepper in the glass house during the whole six weeks of experiment.