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1.
Holographic interferometry is proposed to detect the change in the mechanical responses of reed stems growing in eutrophic, as compared with those in healthy, water bodies. The detection of the difference in behaviour could be a sensitive way to index the degree of eutrophication. An interferometric method based on holomicroscopic moiré is developed and preliminary results obtained are presented.  相似文献   
2.
巢湖主要入湖河道磷的污染现状   总被引:6,自引:0,他引:6  
为了解巢湖主要入湖河道中总磷的污染状况,进行了为期三年每月一次的污染调查,十五里河、南淝河、双桥河,污染较重,超出了(GH281-1999)《地表水环境质量标准》的V娄标准。污染主要来自工业废水、生活污水、和农业面源。认为只有开展农业面源污染治理,城市环境综合整治,城市环境综合整治,加强和削减农业化肥的使用量,使得入湖河道水质变好,巢湖的富营养化才能得到控制。  相似文献   
3.
火焰原子吸收光谱法测定南湖菱中矿质元素   总被引:5,自引:0,他引:5  
用火焰原子吸收光谱法测定嘉兴南湖菱中钾、钠、钙、镁、铁、铜、锌、锰、镉、铅金属元素的含量。结果表明,南湖菱中有较高的矿物质营养价值,有害元素的含量低于国家食品允许标准。  相似文献   
4.
盐卤硼酸盐化学 Ⅻ. MgO·3B2O3·7H2O的热行为和脱水动力学   总被引:1,自引:0,他引:1  
通过对合成MgO·3B2O3·7H2O的热分析研究确定热脱水反应的阶段、温度和产物,给出脱水过程的热化学反应方程式.利用甲醇、水与三氧化二硼之间的酯化反应进行相分离,确定该化合物高温结晶化产物的物相组成为晶态六硼酸镁(2MgO·3B2O3)和无定形B2O3.对该化合物的TG和DTG数据进行处理结果,给出了相应的非等温热脱水反应动力学方程.  相似文献   
5.
Analysis of Toxic Aluminium Species in Natural Waters   总被引:1,自引:0,他引:1  
Aluminium is known to be toxic to a wide range of aquatic organisms under certain conditions. Monomeric hydroxy ions have been found to be primarily responsible for aluminium aquatic toxicity.A survey of aluminium toxicity and a brief discussion of speciation schemes are presented. The fast reaction of Al3+ with pyrocatechol violet (PCV) followed by spectrophotometric analysis is a frequently used method for aluminium speciation. By using a flow system, one obtains fairly exact and reproducible control of the reaction time, and as a result it provides a direct method of analysis for free aluminium (including inorganic monomeric aluminium).The PCV-method has been adapted for the determination of aluminium in carbonate-rich natural waters using an improved buffering system. Thus it is possible to monitor aluminium concentrations in lake water as well as in pore water of the sediments of eutrophicated hardwater lakes that has been treated with aluminium salts as a restoration measure.  相似文献   
6.
Abstract

The use of classical urea inclusion techniques for the separation of straight chain hydrocarbons from branched and cyclic compounds is satisfactory when applied to mixtures in the milligram to gram ranges, but leads to low separation efficiencies when quantities in the microgram to milligram range are involved. In this study, a modified inclusion technique using an urea-packed milli-bore column and a catalytic eluent is described. Examples of its use for the separation of mixtures of linear and cyclic hydrocarbons from 30μg up to a few milligrams are given. The versatility of this technique for the analyses of low amounts of environmental samples is described, and an application to the hydrocarbon fraction of surface sediment from lake Leman (Switzerland) is presented.  相似文献   
7.
论卤盐养生(8)   总被引:1,自引:0,他引:1  
卤盐(包括食盐)是中国矿物药的重要组成部分。从文化价值、临床应用和情志调摄3个方面诠释了卤盐的养生学意义,并全面、详细地阐述了食盐对中国古代文化的四大贡献、6种盐类的现代临床应用价值以及盐湖旅游的6项要素;列举了160多个盐湖卤水的主要化学成分、矿化度或微量元素;摘录了论述卤盐主治功用的古今文献。本文分期刊出。  相似文献   
8.
Synthetic musks, substitutes for natural musks, are widely distributed in environment. They have been detected in water, sludge, fish, shrimp, mussels and other aquatic animals, and even in human's adipose tissue, blood and breast milk. In this study, a new extraction procedure, based on the accelerated solvent extraction (ASE) and in cell clean-up technique was developed and successfully coupled with gas chromatography-mass spectrometry (GC/MS) for the analysis of musks in sediment samples. With this method, the limits of detection as low as 0.03–0.05?ng?g?1 and the recovery rate of 86.0%–104% are achieved. When compared with soxhlet extraction (SE) and ultrasonic extraction (USE), ASE not only has the best extraction efficiency but also has advantage in extraction time and solvent consumption. Eight synthetic musks, including six polycyclic musks (Tonalide (AHTN), Galaxolide (HHCB), Phantolide (AHDI), Traseolide (ATII), Cashmeran (DPMI) and Celestolide (ADBI)) and two nitro musks (musk xylene (MX) and musk ketone (MK)), were evaluated in sediment samples collected from 15 selected locations of the Taihu lake, one of the largest freshwater lakes in China. The contents of synthetic musks in sediment samples range from 0.336 to 3.10?ng?g?1 for HHCB, 0.184 to 1.21?ng?g?1 for AHTN, below detection limit (BDL) to 0.349?ng?g?1 for MX, and BDL to 0.0786?ng?g?1 for MK. The contents of DPMI, ADBI, AHMI and ATII are below detection limit in all samples. The results reflect current status of fragrance compound pollution in this area, and provide basic data for environmental policy making.  相似文献   
9.
卤盐(包括食盐)是中国矿物药的重要组成部分。从文化价值、临床应用和情志调摄3个方面诠释了卤盐的养生学意义,并全面、详细地阐述了食盐对中国古代文化的四大贡献、6种盐类的现代临床应用价值以及盐湖旅游的6项要素;列举了160多个盐湖卤水的主要化学成分、矿化度或微量元素;摘录了论述卤盐主治功用的古今文献。本文分期刊出。  相似文献   
10.
Vincent van Gogh used fugitive red lake pigments that have faded in some paintings. Mapping their distribution is key to understanding how his paintings have changed with time. While red lake pigments can be identified from microsamples, in situ identification and mapping remain challenging. This paper explores the ability of molecular fluorescence imaging spectroscopy to identify and, more importantly, map residual non‐degraded red lakes. The high sensitivity of this method enabled identification of the emission spectra of eosin (tetrabromine fluorescein) lake mixed with lead or zinc white at lower concentrations than elemental X‐ray fluorescence (XRF) spectroscopy used on account of bromine. The molecular fluorescence mapping of residual eosin and two carmine red lakes in van Gogh's The Olive Orchard is demonstrated and compared with XRF imaging spectroscopy. The red lakes are consistent with the composition of paint tubes known to have been used by van Gogh.  相似文献   
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