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91.
Tris[2-methacryloyloxy ethyl] phosphate (TMEP), bis(2-methacryloyloxy) ethyl phosphate (DMEP), and 2-(methacryloyloxy ethyl)
phosphate (MMEP) were synthesized from phosphorous oxychloride and 2-hydroxyethyl methacrylate, which can be used as flame
retardant monomers for UV-curable coating systems. The characterization of the synthesized monomers was carried out by 1H-NMR, FT-IR, thermo-gravimetric analysis, and the limited oxygen index (LOI) test. The thermal behavior of the cured films
depended on phosphorous content and the methacrylate groups in the monomer. The UVcured films from TMEP, DMEP, and MMEP monomers
showed LOIS of 28.5, 30.3, and 35.1 respectively. Also, LOI up to 25.4 was obtained for the UV-coated cotton fabrics, which
presumably occur through a condensed phase mechanism as verified in the increased residue number. The higher performance of
UV-coated cotton fabrics compared to PET was attributed to the facile dehydration and crosslinking of the cellulosic materials. 相似文献
92.
Jeonghwan Park Hyung‐Bae Kim Pyong‐Kih Kim Jae‐Yoon Jo 《Journal of the World Aquaculture Society》2009,40(2):207-215
Nitrogen excreted by aquatic animals mainly takes the form of metabolic wastes such as feces and ammonia, which is accumulated in the intensive aquaculture system and causes serious environmental contamination. So it is very important to determine the waste excretion characteristics of aquatic animals for the development of practical and nonpolluting land‐based aquaculture. Abalone has a unique feeding habit and feeding regime, different from those of finfish; abalone gnaw feed seaweed to produce feces and ammonia continuously. In this study, the rates of feces production and ammonia excretion of pacific abalone, Haliotis discus hannai, of three shell lengths (3, 5, and 7 cm) were investigated under three different temperature conditions (12, 16, and 20 C). All experiments were performed in triplicate in a semirecirculating aquaculture system. Feces were collected for 5 d, and ammonia concentrations (total ammonia nitrogen [TAN]) in the tank inlet and outlet were monitored every 4‐h interval for 24 h at the fourth day of the feces collection. The regressions for the weight‐specific feces production rate (g feces/kg abalone/d) and the weight‐specific TAN excretion rate (mg TAN/kg abalone/d) in relation to water temperature (T, C) and shell length (L, cm) were weight‐specific feces production rate = exp(1.575 ? 281.2/T2 – 0.142L), r2 = 0.9550, and weight‐specific TAN excretion rate = exp(5.052 ? 277.1/T2 ? 0.136L), r2 = 0.9598. Pacific abalone produced 108.3–111.7 g feces and excreted 3.83 g TAN/kg seaweed ingested (dry weight). 相似文献
93.
Okorie E. Okorie Su Hong Ko Sugeun Go Jun‐Young Bae Gwang Yeol Yoo Jun‐Ho Lee Tae‐Ik Kim Sungchul C. Bai 《Journal of the World Aquaculture Society》2011,42(5):657-666
A 14‐wk feeding trial was carried out to evaluate the optimum dietary riboflavin (vitamin B2) level in juvenile sea cucumber, Apostichopus japonicus. A total of 360 sea cucumbers averaging 1.49 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks, and each tank was then randomly assigned to one of three replicates of six diets containing 0.29 (B20), 4.22 (B24), 8.93 (B29), 17.9 (B218), 56.7 (B257), and 577 (B2577) mg riboflavin/kg diet. At the end of 14 wk of feeding trial, average weight gain (WG) of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly (P < 0.05) higher than that of animals fed B20 diet. WG of sea cucumbers fed B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Specific growth rate of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Feed efficiency of sea cucumbers fed B29, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Although significant differences were recorded in proximate composition of sea cucumbers fed the experimental diets, no clear trends were observed. The ANOVA test suggested that the optimum dietary riboflavin level in sea cucumber could be 17.9 mg/kg diet but broken‐line analysis of WG indicated a level of 9.73 mg riboflavin/kg diet. Therefore, these results may indicate that the optimum dietary riboflavin level in sea cucumber could be higher than 9.73 mg/kg diet but lower than 17.9 mg/kg diet. 相似文献
94.
Asami Yoshida Inwoo Bae Hiroko Sonoda Ryuichi Masuo Sachie Oda Min-Jie Cao Kiyoshi Osatomi Kenji Hara 《Fisheries Science》2009,75(5):1317-1322
Gelatinolytic enzymes were partially purified from the skeletal muscle of red sea bream Pagrus major and characterized to obtain information on post mortem tenderization of fish muscle. Four gelatinolytic activities, G1 (90 kDa),
G2 (65 kDa), G3 (60 kDa), and G4 (100 kDa), were detected in the Q Sepharose column. G1, the major gelatinolytic enzyme, and
G4 were identified as serine proteinases from results of inhibitor spectrum and substrate specificity. By contrast, G2 and
G3 were found to be metalloproteinases since these were inhibited by ethylenediamine tetraacetic acid and o-phenanthroline, and activated by 4-aminophenylmercuric acetate. The optimum pH and temperature of these enzymes were in the
ranges of 7–9 and 20–40°C, respectively. 相似文献
95.
Upon UV irradiation wool fabrics can be photografted with photoactive acrylamido dyes at room temperature without photoinitiaors, which is eco-friendly coloration process compared with conventional adsorption-based dyeing. Acrylamide addition as a comonomer can improve the photografting probably by reducing the steric hindrance between the bulky dyes during the photocopolymerization. Even without photointiators and neutral salts, the optimal K/S values of the photografted wool reached upto 18.7 and 18.5 for Reactive Red 84 and Yellow 39 dyes respectively. The optimal UV-grafting coloration can be achieved when a UV energy of 25 J/cm2 was irradiated on the padded fabrics with 6.3 %owf dye containing 0.65 mole ratio of acrylamide to the dyes. Furthermore, the color fastness of the grafted fabrics was as good as those of conventionally dyed fabrics due to the copolymerization of dyes and comonomers. 相似文献
96.
Okorie Eme Okorie Su Hong Ko Sugeun Go Seunghyung Lee Jun Young Bae Kyungmin Han Sungchul C. Bai 《Journal of the World Aquaculture Society》2008,39(6):758-765
A 14‐wk feeding trial was carried out to evaluate the optimum dietary ascorbic acid (AA) level in juvenile sea cucumber, Apostichopus japonicus. Sea cucumbers averaging 1.49 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks of 20 L capacity in a recirculating system (20 animals per tank). Six semipurified experimental diets were formulated to contain 0 (l ‐ascorbyl‐2‐monophosphate [AMP]; AMP0), 30 (AMP24), 60 (AMP48), 120 (AMP100), 240 (AMP206), and 1200 (AMP1045) mg AA/kg diet in the form of AMP using casein as the main protein source. Sea cucumbers were fed each of the six experimental diets in triplicate groups. At the end of 14 wk of feeding trial, weight gain (WG), specific growth rate (SGR), and feed efficiency (FE) of sea cucumbers fed AMP100, AMP206, and AMP1045 were significantly (P < 0.05) higher than those of animals fed AMP0, AMP24, and AMP48. However, there were no significant differences in WG, SGR, and FE among sea cucumbers fed AMP100, AMP206, and AMP1045 and among animals fed AMP0, AMP24, and AMP48. Whole‐body vitamin C concentration increased with AA content of the diets. Broken‐line analysis of WG showed an optimum dietary AA level of 105.3 mg AA/kg diet in sea cucumber. These results indicated that the optimum dietary vitamin C level in sea cucumber in the form of AMP could be greater than 100 mg AA/kg diet but less than 105.3 mg AA/kg diet. 相似文献
97.
A new trial to determine the dyeing properties of cotton and silk fabrics with a black cowpea seed coat as crop waste was investigated. The natural dye anthocyanins were extracted from a black cowpea seed coat in an aqueous solution and used to dye silk and cotton. The optimal conditions for colorant extraction were an aqueous solution of a dried seed coat of black cowpea in a 1:10 liquor ratio at 70 °C for 4 hours with pH of 4. The best dye-uptake of silk and cotton fabric were obtained when the pH was 3.5 and 3.0 respectively, the temperature was 80 °C for 1 hour and the liquor ratio of black cowpea was 1:20. Different colors as dusky brown, brown, faint yellow, light green, reddish brown, cyan and green could be obtained using a various kind of mordants. The depth and brightness of color tones were affected by different dyeing and mordanting pH conditions. The colors of the fabrics were examined using a computer color matching system in terms of the K/S values and CIELAB color-difference values. The dyeing was evaluated using standard light, wash and heat fastness tests. Good wash and heat fastness were obtained but the poor light fastness indicated the need for improvement to fulfill the requirement for textile applications. 相似文献
98.
Estimation of flood risk index considering the regional flood characteristics: a case of South Korea
Jung Younghun Shin Yongchul Jang Chun Hwa Kum Donghyuk Kim Young Sug Lim Kyoung Jae Kim Hyun Bae Park Tae Sun Lee Seung Oh 《Paddy and Water Environment》2014,12(1):41-49
Global warming is increasing the variability of climate change and intensifying hydrologic cycle components including precipitation, infiltration, evapotranspiration, and runoff. These changes increase the chance of more severe and frequent natural conditions, and limit ecosystem function and human activities. Adaptation to climate change requires assessment of the potential disaster risk. The objectives of this study were to estimate the flood risk index (FRI) considering regional flood characteristics at the national level and to prioritize the factors affecting flood risk through principal component analysis. FRI was estimated based on the Delphi survey results from 50 water resources experts in South Korea. The potential risk analysis was conducted for 229 local governments in South Korea. The results showed that natural and social factors were more influential flood risk factors to South Korea than administrative and economic and facility factors. Specifically, natural, social, administrative and economic, and facility factors were, respectively, highest at Jindo-Gun in Jennam-Do, Gumi-Si in Kyongsanbuk-Do, Dong-Gu in Incheon-Si, and Suwon-Si, Kyonggi-Do. Overall, the highest FRI is shown in Anyang-Si, Kyongggi-Do. The spatial distribution of the FRI was high in the southeastern coastal region and basins of the two biggest rivers in South Korea, and normalized flood frequency followed spatial patterns similar to FRIs. This study provided information on the relative flood risk index among administrative units for investment prioritization in flood risk management. In this regard, the suggested FRI is expected to significantly contribute to methodical and economic improvements in budget allocations for flood risk management. 相似文献
99.
The influences of a series of new azo direct dyes including copper-complexes based on benzidine congeners, 2,2′-dimethyl-5,5′-dipropoxybenzidine
and 5,5′-dipropoxybenzidine, were examined using microorganism, Daphnia magna. The purpose of the research described in this
paper was to use bioassays with daphnids to determine the aquatic toxicity of new azo dyes in which copper was incorporated.
The results clearly show that copper has negative effects to aquatic ecosystem as expected. The study also suggested that
the assay with Daphnia magna was an excellent method to evaluate the influences of dyes to the aquatic environment. 相似文献
100.
J. Y. Kim Y. S. Ghim S. B. Lee K.-C. Moon S.-G. Shim G. N. Bae S.-C. Yoon 《Water, air, and soil pollution》2010,205(1-4):259-272
The amounts of nitrogen and sulfur deposited in the region of the Yellow Sea in both dry and wet forms were estimated focusing on the period between 1999 and 2000. Dry deposition fluxes were obtained using concentrations from ground stations on both Korean and Chinese sides and from shipboard and aircraft measurements. Wet deposition fluxes were determined at ground stations on the Korean side. The dry deposition flux over the Yellow Sea was much greater than those for other world oceans. As a whole, the amounts of wet depositions of nitrogen and sulfur were 1.9 and 1.5 times larger than the amounts of respective dry depositions. Substantial influence from China caused by high emissions in East China and westerly wind was possibly suggested. However, the influence from nitrogen emission in Korea was also confirmed. 相似文献