亚甲基蓝在水体系中的光化学降解研究   总被引：1，自引：0，他引：1  

杨桂朋  孙璐霓  周立敏 《中国海洋大学学报(自然科学版)》2009,39(1)

研究水体系中亚甲基蓝的光化学降解.结果表明,在高压汞灯照射下,亚甲基蓝在人工海水中降解得最快,蒸馏水次之,而在天然海水中降解得最慢.通过对比研究发现.重金属离子(Cu2+,Zn2+,Cd2+,Hg2+)和腐殖酸能够在一定程度上抑制亚甲基蓝的光降解;而丙酮能促进亚甲基蓝的光降解.由此可见,重金属离子和腐殖酸可能是造成亚甲基蓝在天然海水中降解缓慢的主要因素之一.  相似文献   

Accumulation and depuration of pectenotoxins in brown crab Cancer pagurus     

LI Zhaoxin 《中国海洋湖沼学报》2009,27(2)

Pectenotoxins (PTXs) are a group of marine algal toxins. In this study, the accumulation and depuration of pectenotoxins in brown crab Cancer pagurus were investigated. Crabs were fed with toxic blue mussels Mytilus edulis for 21 days and then depurated for 42 days. Toxins were extracted with methanol from the digestive glands of contaminated crabs, uncontaminated crabs (control group) and from blue mussels for comparison. Extracts were analyzed by liquid chromatograph coupled with tandem mass spectrometry (LC-MS-MS). The concentrations of PTX-2, PTX-2 SA, 7-epi-PTX-2 SA, and PTX-12 were analyzed in two batches of toxic blue mussels and the crabs. A one-compartment model was applied to describe the depuration of PTXs. The half-life of PTXs was estimated to be 6-7.5 days. After depuration for 42 days, the amount of PTXs measured in the crab digestive glands was less than 1 μg/kg.  相似文献   

Sequential injection analysis of nanomolar soluble reactive phosphorus in seawater with HLB solid phase extraction     

Jian Ma  Dongxing Yuan  Ying Liang   《Marine Chemistry》2008,111(3-4):151-159

A cartridge of solid phase extraction (SPE), hydrophilic–lipophilic balance (HLB), has been used to enrich phosphomolybdenum blue (PMB) from water samples without any other additives. Based on this, the previous on-line SPE method established for the determination of nanomolar soluble reactive phosphorus (SRP) in seawater has been greatly improved. Cetyltrimethylammonium bromide (CTAB), the cationic surfactant needed for the formation of the PMB-CTAB paired compound that could be extracted on a Sep-Pak C18 cartridge using the previous method [Liang, Y., Yuan, D.X., Li, Q.L., Lin, Q.M., 2007. Flow injection analysis of nanomolar level orthophosphate in seawater with solid phase enrichment and colorimetric detection. Marine Chemistry 103, 122–130.], was not necessary. Thus the longer time and higher temperature required for the complete formation of the PMB-CTAB compound were no longer needed. In addition, with application of the sequential injection analysis technique the proposed method showed the advantages of being much faster, simpler, sample and reagent saving, as well as more convenient in operation. The PMB compound formed under room temperature was efficiently extracted on an in-line HLB cartridge, rapidly eluted by 0.15 mol/L NaOH solution, and finally determined with a laboratory-made spectrophotometer at 740 nm. Experimental parameters, including the volume of reagents added, sample loading flow rate, and eluting flow rate, were optimized. Time and temperature for the PMB reaction, and salinity effect were also studied, and these were found to have no severe effect on the detection. With variation of sample loading time at a fixed flow rate, a broadened determination range of 3.4 to 1134 nmol/L phosphate could be obtained. The recovery and the method detection limit of the proposed method were found to be 94.4% and 1.4 nmol/L, respectively. The relative standard deviation (n = 7) was 2.50% for the sample at a concentration of 31 nmol/L phosphate. Two typical seawater samples were analyzed with both the proposed method and the magnesium hydroxide-induced coprecipitation method and, using the t-test, the results of the two methods showed no significant difference.  相似文献   

蓝绿空间暴露对老年人健康的邻里影响   总被引：1，自引：0，他引：1  

陈玉洁  袁媛  周钰荃  刘晔 《地理科学》2020,40(10):1679-1687

利用2018年广州社区问卷数据、遥感影像、城市街景、环境污染等多元数据,提取多种蓝绿空间指标,并使用多层模型、中介效应模型和倾向值匹配法,探讨中国城市背景下蓝绿空间暴露影响老年人健康的“生物?心理?社会”邻里影响路径和机制,以及对不同社会阶层间的差异。研究发现,社区层面的蓝绿空间暴露与老年人的身心健康均存在显著相关;周围蓝绿空间程度通过促进体育锻炼、缓解压力提升老年人的身体健康,可达性通过促进社会交往提升老年人的心理健康;蓝绿空间暴露对老年人健康的影响在不同阶层间存在差异。为健康老龄化、健康城市建设提供科学参考。  相似文献   

载铜蒙脱石吸附亚甲基蓝的试验研究     

马玉龙  许梓荣  尤萍 《矿物学报》2005,25(2):147-152

采用离子交换法制得载铜蒙脱石,研究蒙脱石和载铜蒙脱石对亚甲基蓝（MB）的吸附性能,结果表明载铜蒙脱石的吸附能力低于蒙脱石。温度、介质pH值和离子强度对吸附剂的吸附性能有不同程度的影响;蒙脱石和载铜蒙脱石吸附MB等温线较好地符合BET和Langmuir等温方程,其吸附过程均为热力学自发过程。  相似文献   

Impact of precipitation and temperature changes on hydrological responses of small-scale catchments in the Ethiopian Highlands     

Tatenda Lemann  Vincent Roth  Gete Zeleke 《水文科学杂志》2017,62(2):270-282

The hydrological response of catchments with different rainfall patterns was assessed to understand the availability of blue and green water and the impacts of changing precipitation and temperature in the Ethiopian Highlands. Monthly discharge of three small-scale catchments was simulated, calibrated, and validated with a dataset of more than 30 years. Different temperature and precipitation scenarios were used to compare the hydrological responses in all three catchments. Results indicate that runoff reacts disproportionately strongly to precipitation and temperature changes: a 24% increase in precipitation led to a 50% increase in average annual runoff, and an average annual rainfall–runoff ratio that was 20% higher. An increase in temperature led to an increase of evapotranspiration and resulted in a decrease in the rainfall–runoff ratio. But a comparison of combined results with different climate change scenarios shows that downstream stakeholders can expect a higher share of available blue water in the future.  相似文献   

太湖底泥表层越冬藻类群落动态的荧光分析法初步研究   总被引：28，自引：10，他引：18  

阎荣  孔繁翔  韩小波 《湖泊科学》2004,16(2):164-169

为探索春季湖泊底泥表层不同藻类群落的复苏规律,本实验采集了太湖梅梁湾地区的底泥,应用荧光分析法测定藻蓝素,同时测定湖泊底泥中的叶绿素a和叶绿素b,确定春季梅梁湾底泥中不同藻类类群的色素含量变化,说明荧光分析法可以应用于底泥色素分析中,初步探讨了蓝藻群落和非蓝藻群落在春季温度上升期间恢复生长过程的差异。  相似文献   

现代海洋药物研发进展与浅析          下载免费PDF全文

冯贻东  冯汉林 《应用海洋学学报》2021,40(2):366-371

海洋药物历史悠久但发展缓慢,在90年代开始正式进入到热点研究领域.随着海洋药物研究的深入,国际范围内逐渐有数个药物获得上市批准,并有大量的海洋药物或衍生物进入不同阶段的临床试验;但海洋药物的发展速度仍远慢于其他类型的药物.海洋来源的物质具有区别于其他药物的特点,结构新颖、活性独特,是优良的药物宝库.但海洋药物发展受到多...  相似文献   

海峡经济区的区位优势与优先领域     

陈述彭  陆锋 《地域研究与开发》2007,26(3):1-5,15

在经济全球化的新形势下,台湾海峡两岸经济发展的差距正在缩小,科技合作的空间正在扩大.海峡两岸,唇齿相依,在台风预警、应急救援、地震灾害预报、海底资源勘探开发、通信光缆安全保障等诸多领域,可以优势互补,互利双赢.在客家、玛祖和疍民等面向海洋的蓝色文明的文化交流方面,底蕴深厚、源远流长.当海岛经济发展到比较成熟的阶段时,趋向回归大陆,乃是历史的必然规律.  相似文献   

Absolute proper motions of blue objects in the vicinity of M33     

G. A. Richter  R.-D. Scholz 《Astronomische Nachrichten》1990,311(1):31-34

36 objects with mainly negative (U—B) indices were investigated for variability and proper motions. 10 objects with significant or suspected proper motions and 8 variable objects were detected. Using these criteria, it was possible to separate white dwarfs from quasi-stellar objects to some extent.  相似文献