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101.
102.
建立了海产品中的溴酚类海洋风味素的毛细管气相色谱-质谱联用检测法。样品中溴酚类化合物在挥发油测定器中用乙酸乙酯通过循环蒸馏萃取,浓缩后用电子轰击源在特征离子碎片扫描检测模式下进行检测。结果表明,5种溴酚类化合物在SBP-50柱上得到良好的分离,色谱出峰尖锐,没有杂峰干扰。本方法在2.5~40 mg·L~(-1)浓度范围内线性关系良好,最低检测限低于1ng·mL~(-1)。当向25.00g样品中添加溴苯酚各2.0μg时,平均回收率分别达到90.45%(2-BP)、60.49%(4-BP)、85.79%(2,4-DBP)、84.98%(2,6-DBP)、90.80%(2,4,6-TBP),标准相对偏差为1.37%~4.16%。对市场上销售的几种海洋经济动物测定,溴酚类风味素含量在5.40~31.38 ng·g~(-1)范围内,而所测得的淡水青虾中溴酚类风味素含量只有0.18 ng·g~(-1)。 相似文献
103.
研究张掖国家湿地公园附植硅藻群落现状,为保护寒、旱区湿地水生植物与生物多样性提供理论依据。2017年夏、秋从张掖国家湿地公园浅水湖泊采集12种常见水生植物,采集植物上附植硅藻,并在水质富营养化评价的基础上进一步分析硅藻的种类分布、优势种、多样性和聚类性。结果表明,张掖国家湿地公园水体轻度富营养化;共检出附植硅藻39属158种(含变种),其中舟形藻属种类最多(18种),其次为菱形藻属(16种)、桥弯藻属(15种)和脆杆藻属(13种);Achnanthedium minutissimum为分布最为广泛的优势种,其次为Ulnaria acus和Encyonopsis subcryptocephala;Shannon-Weaver多样性指数在1.41~3.13,Pielou均匀度指数在0.58~1.07,均是秋季显著高于夏季(P0.05,t-test);Cody指数与聚类分析表明,在同一时期内附植硅藻种类组成的相似程度和优势种分布对部分宿主植物的选择趋于一致,但也有部分宿主植物之间附植硅藻群落结构仍然存在较大差异。 相似文献
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105.
浙江省作为沿海省份,随着其工业经济的快速发展和人民生活需求的提高,一方面工业企业向环境排放了大量的污染物,使得污染物最终流入大海,从而破坏了水产品的生长环境;另一方面由于人均可支配收入的增加,人们加大了对水产品的消费需求。近年来浙江省海洋环境形势严峻,其好坏直接影响到水产品贸易的发展。文章拟从分析工业发展和城市化引起的海洋污染入手,着重阐明海洋环境的好坏与水产品出口的关系,并提出发展水产品贸易的对策建议。 相似文献
106.
Effect of temperature and cell density on ethanol fermentation by a thermotolerant
aquatic yeast strain isolated from a hot spring environment 总被引:2,自引:0,他引:2
ABSTRACT: A thermotolerant, fermentative yeast strain named RND13 from a hot spring drainage was evaluated for its ethanol-producing ability at elevated temperatures at a high substrate concentration [15% (w/v) glucose] close to the level reflecting industrial practice. The RND13 was capable of utilizing glucose almost completely at 40°C with increasing inoculum size, producing ethanol up to 6.6% (w/v), which is comparable to levels (7.0–7.2%) at 30°C. The maximum rate of ethanol production by the RND13 was found to be 9.0 g/L per h at 40°C in an inoculum sized 5% (w/v). At 43°C, however, the RND13 could not utilize glucose to completion and showed a slight drop in the extent of produced ethanol [6.0% (w/v)]. Thus, the culture at 40°C with a 5% cell inoculum was considered to be the optimal condition for ethanol production at higher temperatures in terms of batch fermentation. In the phylogenetic analysis based on the small-subunit rDNA sequence, the strain was grouped together with both Candida glabrata and Kluyveromyces delphensis , which are relatively close to Saccharomyces cerevisiae . 相似文献
107.
108.
I. Growns P. C. Gehrke K. L. Astles & D. A. Pollard 《Fisheries Management and Ecology》2003,10(4):209-220
Fish assemblages in six reaches of the Hawkesbury–Nepean River were studied to identify the effects of two types of riparian vegetation; well‐vegetated banks supporting complex flora dominated by trees and shrubs, and grassed banks, that have been colonised only by grasses after historical deforestation. The fish assemblages showed both spatial and temporal differences and habitats adjacent to grassed banks supported more individuals and more fish species than well‐vegetated banks. Three small species of fish, firetail gudgeon, Hypseleotris galii (Ogilby), flathead gudgeon, Philypnodon grandiceps (Krefft), and empire gudgeon, Hypseleotris compressa (Krefft), occurred in greater abundances adjacent to grassed banks, but freshwater mullet, Myxus petardi (Castelnau), were less abundant near grassed banks than beside well‐vegetated banks. Differences were also shown in the size frequencies of the four larger fish species between riparian vegetation types. The observed differences in the distributions of fish species appeared to be related to the greater abundance aquatic macrophytes near grassed banks, probably an effect of shading of macrophytes near well‐vegetated banks. 相似文献
109.
开发绿色水产品是发展渔业经济的必由之路 总被引:2,自引:0,他引:2
本文提出在发展渔业经济过程中遇到的一些问题,指出开发绿色水产品是发展渔业经济的必由之路,HACCP认证体系是开发绿色水产品的重要手段和基本保证,中国加入WTO后,面临严峻的国际市场竞争也要求我国水产业积极开发绿色水产品,提高产品质量,加强水产品出口的竞争力。 相似文献
110.
The market for marine ornamentals encompasses all live marine species (fish and invertebrates) destined for the aquarium trade. In 1998, U.S. imports and exports were valued at approximately US $1.5 billion at the border (all dollar values cited in this paper are $US). In Florida, cultured freshwater and collected saltwater species accounted for $70 million and $4 million, respectively, in annual dockside revenue. To help explain Florida's marine landings and provide suggestions for future resource management and market campaigns that reflect the perceptions of the industry, a survey of wholesalers was initiated in 1999. Preliminary results indicate that there are several intermediate wholesale markets. Florida firms are closer to the supply as many also collect. Wholesalers in other states handle more freshwater product, are larger, and tend to import a larger share of their inventory. Consolidation is expected to continue, but niche markets for eco-friendly firms are expected to grow. In Florida, marketing strategies should focus on the observed higher survival rates and increasing supply of the popular invertebrate species. Many wholesalers are concerned about additional regulations that could reduce the number of collectors and thereby increase supply variability, a noted weakness of the Florida industry. 相似文献