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Yu Yuan Wang Le Fu Xiaoting Wang Lei Fu Xiaodan Yang Min Han Zhenlian Mou Haijin Jeon You-Jin 《中国海洋湖沼学报》2019,37(3):836-847
Polypehnol is an important, potentially bioactive component of Sargassum muticum. In this study, ultrasonic assisted extraction of polyphenol-rich substances was performed using a 38% ethanol solution at a solid:liquid ratio of 1:30 at 68℃ for 32 min, determined by single-factor and response surface methodology(RSM) optimization. The content of polyphenol was 5.66 mg/g in the crude extract. Further extraction showed that the polyphenol mainly distributed in ethyl acetate(SKEE) and water phases(SKEW).The anti-oxidation test by electron spin resonance(ESR) spectrum showed that the SKEE had the strongest scavenging activity on DPPH(1,1-diphenyl-2-picrylhydrazyl) and alkyl radicals. SKEE was shown noncytotoxic but could inhibit the generation of cellular ROS, showing protective effects in H_2O_2 and AAPHinduced Vero cells and UV-B irradiated HaCaT cells. SKEE also significantly inhibited the release of NO of LPS-induced RAW 264.7 cells. Therefore, the polyphenol-rich extracts in ethanol and ethyl acetate showed excellent anti-oxidant and anti-inflammatory activities, which is beneficial to the development of high-value bio-substances. 相似文献
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韩国的乡村林木处于偏远村庄附近,单独的树木或一片树林,往往构成风水因素。乡村林木也有野生动物生境的功能,有益于农业生物多样性。本文中,乡村林木分为4种类型(天然林、半天然林、半人工林、人工林)23个主要树种(优势种或次优势种)。赤松(Pinus densiflora)在50个地点是优势种,光叶榉(Zelkova serrata)在45个地点为优势种。乡村林木立地植物共分125科、519属、1081种。尽管乡村林木占地面积极小,占100 000 km2韩国国土面积的0.00278%,但这种生态系统具有重要的生物多样性和生境保护功能。乡村林木不仅是保育生物多样性的一个基础,还能为韩国提供生态系统服务。 相似文献
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Yeon-Hee Kim Eun-Hee Jeon Dong-Eon Chang Hee-Sang Lee Jong-Im Park 《Asia-Pacific Journal of Atmospheric Sciences》2010,46(3):287-303
The THORPEX-Pacific Asian Regional Campaign 2008 (T-PARC 2008) was performed during the period of August 1 through October 4, 2008, and mainly focused on the genesis, intensification, recurvature, and extra-tropical transition over the western North Pacific in collaboration with TCS-08 and DOTSTAR. This study investigates the impact of dropsonde observations on the improvement of predictive skills for Typhoon Sinlaku (0813) and Jangmi (0815) during T-PARC 2008. Twelve and six cases were selected for Sinlaku and Jangmi, respectively. The dropsonde data were assimilated by the Weather Research and Forecasting (WRF)-Three-Dimensional Variational system (3DVAR), and then the typhoon track was obtained by running a WRF model for up to 72 hours. Consequently, the assimilation of the dropsonde data had positive impacts on the typhoon track forecast and lead to mean track error reductions of 22.5% and 17.0% for Typhoon Sinlaku and Jangmi, respectively. Subsequent experiments were also conducted to determine the sensitivities of storm activity in the horizontal and vertical distributions and the dynamic and thermodynamic variables using the dropsonde data. The results show that sondes released south of storms around the middle troposphere (500～850 hPa) are more effective in improving the track forecast. The dynamic variables mainly affect the storm tracks, while the thermodynamic variables mainly affect the central pressure of the storm. 相似文献
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The effects of monochromatic (blue, yellow and red LED) and mixed wavelengths (fluorescent lamp) on the adsorption and absorption of Cu and Zn by Phaeodactylum tricornutum, Nitzschia sp., Skeletonema sp., and Chlorella vulgaris were investigated. In addition, we confirmed the potential of microalgae for phytoremediation of these heavy metals from contaminated marine sediment by using microcosm experiments that incorporated LEDs and semipermeable membrane (SPM) tube containing microalgae. Among the four microalgae, C. vulgaris grown under red LED exhibited the highest Cu and Zn removal with values of 17.5 × 10-15 g Cu/cell and 38.3 × 10-15 g Zn/cell, respectively. Thus, C. vulgaris could be a useful species for phytoremediation. In the microcosm experiments with SPM containing C. vulgaris, the highest Cu and Zn removal from sediment and interstitial water showed under red LED. Therefore, phytoremediation using LED and SPM tube containing microalgae could be utilized as an eco-friendly technique for remediating contaminated marine sediment. 相似文献
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This study assesses potential effects of adaption to climate change in the future as a carbon related value using a baseline and credit approach, considering the implementation of the Reducing Emissions from Deforestation and forest Degradation(REDD) mechanism. Basic data were obtained for implementing the REDD mechanism in the Democratic People's Republic of Korea(DPRK) for scientific decision-making to prevent deforestation and forest degradation. The potential effects according to the implementation of the REDD mechanism in the DPRK based on forest status data(the latest) are as follows. If the deforestation rate is reduced to a level below 6% through a 20-year REDD mechanism beginning in 2011, 0.01–11.64 C-tons of carbon credit per ha could be issued for DPRK. Converted into CO?-tons per ha, this amounts to 0.03–42.68 CO?-tons, which translates to a minimum of 226,000 CO?-tons and a maximum of 289,082,000 CO?-tons overall for forests in DPRK. In terms of carbon price, this measures up to 1.10 million USD–1.4 billion USD, considering that the REDD carbon price in voluntary carbon markets in 2010 was around 5 USD. 相似文献
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Chanhyung Jeon Jae-Hun Park Dong Guk Kim Eung Kim Dongchull Jeon 《Ocean Science Journal》2018,53(2):207-213
An array of 5 pressure-recording inverted echo sounders (PIESs) was deployed along the Jason-2 214 ground track in the North Equatorial Current (NEC) region of the western Pacific Ocean for about 2 years from June 2012. Round-trip acoustic travel time from the bottom to the sea surface and bottom pressure measurements from PIES were converted to sea level anomaly (SLA). AVISO along-track mono-mission SLA (Mono-SLA), reference mapped SLA (Ref-MSLA), and up-to-date mapped SLA (Upd-MSLA) products were used for comparison with PIES-derived SLA (ηtot). Comparisons of ηtot with Mono-SLA revealed that hump artifact errors significantly contaminate the Mono-SLA. Differences of ηtot from both Ref-MSLA and Upd-MSLA decreased as the hump errors were reduced in mapped SLA products. Comparisons of Mono-SLA measurements at crossover points of ground tracks near the observation sites revealed large differences though the time differences of their measurements were only 1.53 and 4.58 days. Comparisons between Mono-SLA and mapped SLA suggested that mapped SLA smooths out the hump artifact errors by taking values between the two discrepant Mono-SLA measurements at the crossover points. Consequently, mapped SLA showed better agreement with ηtot at our observation sites. AVISO mapped sea surface height (SSH) products are the preferable dataset for studying SSH variability in the NEC region of the western Pacific, though some portions of hump artifact errors seem to still remain in them. 相似文献