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基于IGWO与BP神经网络的海洋沉积物质量评价 被引量:2
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作者 李海涛 邵泽东 《计算机仿真》 北大核心 2020年第8期344-347,共4页
针对单因子评价法在海洋沉积物质量评价中评价结果粗糙等问题,提出一种新的利用改进灰狼优化算法(IGWO)优化BP神经网络的海洋沉积物质量评价模型。该模型引入具有快速收敛、简单高效、全局优化能力较强特点的改进灰狼优化算法,在模拟灰... 针对单因子评价法在海洋沉积物质量评价中评价结果粗糙等问题,提出一种新的利用改进灰狼优化算法(IGWO)优化BP神经网络的海洋沉积物质量评价模型。该模型引入具有快速收敛、简单高效、全局优化能力较强特点的改进灰狼优化算法,在模拟灰狼捕猎的过程中得到了BP神经网络的各层权值、阈值的最优解。并以温州东部沿海海域的监测数据作为样本进行海洋沉积物的质量评价,实验结果表明该评价模型具有收敛速度快、准确性较高等特点,能够准确、合理地对海洋沉积物质量做出评价。 展开更多
关键词 改进灰狼优化算法 神经网络 海洋沉积物质量评价
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舟山市小干岛附近海域环境质量现状监测与评价
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作者 曹静 林柏 +1 位作者 赵沧海 叶新荣 《科技创新导报》 2020年第27期125-130,共6页
本文根据2012—2019年在舟山市小干岛附近海域的海水水质和海洋沉积物质量调查监测数据,对小干岛附近海域水质和沉积物环境现状和变化趋势情况进行分析和评价。调查结果表明:2012—2019年调查期间,小干岛附近海域海水各监测因子中无机... 本文根据2012—2019年在舟山市小干岛附近海域的海水水质和海洋沉积物质量调查监测数据,对小干岛附近海域水质和沉积物环境现状和变化趋势情况进行分析和评价。调查结果表明:2012—2019年调查期间,小干岛附近海域海水各监测因子中无机氮和活性磷酸盐分别存在超过第四类和第三类海水水质标准的现象,而其他海水水质监测因子均可达到第一类海水水质标准要求。调查海区沉积物环境各监测因子均能够达到第一类海洋沉积物质量标准要求,沉积物环境良好。小干岛附近海域呈现富营养化状态,海水中无机氮和活性磷酸盐的环境承载力不足。 展开更多
关键词 小干岛 海水水质 海洋沉积物质量 富营养化 海域环境承载力
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Determination of Lignin in Marine Sediment Using Alkaline Cupric Oxide Oxidation-Solid Phase Extraction-on-Column Derivatization-Gas Chromatography 被引量:10
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作者 ZHANG Ting LI Xianguo +3 位作者 SUN Shuwen LAN Haiqing DU Peirui WANG Min 《Journal of Ocean University of China》 SCIE CAS 2013年第1期63-69,共7页
Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters (TOMs) in marine environment. Extraction and derivatization of lignin oxidation products (LOPs) are crucial for ... Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters (TOMs) in marine environment. Extraction and derivatization of lignin oxidation products (LOPs) are crucial for accurate quantification of lignin in marine sediment. Here we report a modification of the conventional alkaline cupric oxide (CuO) oxidation method, the modification consisting in a solid phase extraction (SPE) and a novel on-column derivatization being employed for better efficiency and reproducibility. In spiking blanks, recoveries with SPE for the LOPs are between 77.84% and 99.57% with relative standard deviations (RSDs) ranging from 0.57% to 8.04% (n=3), while those with traditional liquid-liquid extraction (LLE) are from 44.52% to 86.16% With RSDs being from 0.53% to 13.14% (n=3). Moreover, the reproducibility is greatly improved with SPE, with less solvent consumption and shorter processing time. The average efficiency of on-column derivatization for LOPs is 100.8%±0.68%, which is significantly higher than those of in-vial or in-syringe derivatization, thus resulting in still less consumption of derivatizing reagents.Lignin in the surface sediments sampled from the south of Yangtze River estuary, China, was determined with the established method. Recoveries of 72.66% to 85.99% with standard deviation less than 0.01mg/10g dry weight are obtained except for p-hydroxybenzaldehyde. The lignin content ∑8 (produced from 10g dry sediment) in the research area is between 0.231 and 0.587mg. S/V and C/V ratios (1.028 ± 0.433 and 0.192±0.066, respectively) indicate that the TOMs in this region are originated from a mixture of woody and nonwoody angiosperm plants; the high values or (Ad/Al)v suggest that the TOMs has been highly degraded. 展开更多
关键词 LIGNIN alkaline cupric oxide SPE on-column derivatization marine sediments
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