共查询到20条相似文献，搜索用时 78 毫秒
1.
植物样品在500℃灰化,用硝酸、氢氟酸和高氯酸分解,然后在2％的盐酸介质中,用火焰原子吸收分光光度法测定植物样品中的微量铜。该方法简单、快速、准确。方法的检出限为0.55×10~(-6),回收率97％—102％。对含量为5.14×10~(-6),9.43×10~(-6)和17.63×10~(-6)的三个植物样品进行分析,其相对标准偏差分别是4.62％、4.22％和2.00％。 相似文献
2.
区域化探对银的测定检出限要求为(0.1—0.02)×10~(-6),金为0.3×10~(-9)。一般对痕量Au、Ag除采用发射光谱法测定外,多采用两次取样无火焰法单独测定。本试验提出一次取样用石墨炉原子吸收仪连续测定Au、Ag的方法。即取10g化探样品经600℃灼烧、高氯酸、氟化铵预处 相似文献
3.
试样经氢氟酸、硝酸分解,在5％—25％的磷酸介质中,可不经分离在原子荧光光度计上直接测定地质样品中的微量锗。方法的检出限为6.25×10~(-9)g/ml,相对标准偏差为3.20％,回收率加9.2％—105.5％。 相似文献
4.
李绍卿 《地球科学与环境学报》1993,(4)
研究了痕量Bi催化鲁米诺-邻菲啰啉-H_2O_2-Triton x-305体系产生化学发光及非离子表面活性剂敏化化学发光最佳反应条件,拟定了新的化学发光测定Bi的方法。方法最低检出限达3.7×10~(-10)g/ml,测定响应浓度范围为5×10~(-9)～10~(-5)g/ml,回收率为98.7％～103％,相对标准偏差为2.8％～3.5％之间。 相似文献
5.
工业废水中的硝基苯,一、二、三硝基甲苯的衍生物是主要环境污染源。通常,地下水中的硝基苯类含量甚微,现有的化学法、比色法、薄层层析法等分析方法很难满足测试要求。本文采用气相色谱法,利用电子捕获检测器对水中的硝基苯,一、二、三硝基甲苯进行了测试,试验结果表明,该法有较高的灵敏度和准确度。检测限分别为:硝基苯8.13×10~(-6)μg;一硝基甲苯6.98×10~(-8)μg;二硝基甲苯1.7×10~(-8)μg;三硝基甲苯2.90×10~(-6)μg。 相似文献
6.
拟定了用铅空心阴极灯为激发光源,氢化物原子荧光光度法测定地球化学样品中微量铅的方法。在2％HCl-0.08％K_3[Fe(CN)_6]-2％KBH_4体系中,铅的测定灵敏度有明显地提高。该方法操作简便、快速、准确,检出限为8.89×10~(-9)g/ml,精密度为4.12％(n=11)。 相似文献
7.
Trare amounts of benzene hydrocarbons obtained in Jiaozhou Bay (Qindao) were enriched bysorption on a GDX-102 column and eluted by carbon disulfide. The eluted was concenttaled and then de-temened by capillary column gas cbornatognphy.The contents of virious kinds of benzene hydrocarbons in Jiaozhou Bay coastal water were benzene(22.3-141.6)× 10～(-9)g/L, toluate (15.2-94.0) × 10~(-9) g/L, ethyl benzene(11.8-85.1)×10~(-9) g/L, p -xylene(15.2-78.5) ×10(-9) g/L, m-xylene (10.9-79.4) ×10(-9) g/L, o -xylene (12.4-80.1) x ×10(-9)g/L; iso-propyl(8.4- 73.1) x ×10(-9)g/L, n -propyl (6.9-76.4) ×10(-9) g/L, 1, 3, 5-trimethylbenzene (10.9- 35.9)×10(-9) g/L, 1,2, 4-trimethybenzene (10.0- 38.0)×10(-9) g/L, n - butydriare (8. 1 - 34.6) ×10(-9)g/L. The recovery of benzenehydrocarbons was (85.1 -95.6)%. 相似文献
8.
试样经王水分解,在5％—15％的王水介质中,用三苯基膦泡沫塑料对微量银进行分离富集。用ρ为20g/l的硫脲溶液解脱被吸附在泡沫塑料上的银。解脱液在原子吸收分光光度计上测定银量。方法的检出限为0.022×10~(-■),特征浓度为0.014μg/ml,可测定地质样品中0.0X×10~(-6)以上的银量。 相似文献
9.
本文详细研究了氢化物原子荧光法测定硒和碲的工作条件及其它元素的干扰情况。发现通过加入铁盐及提高试液酸度可以较好地消除干扰。拟定了以逆王水加硝酸钾分解样品,用5mol·L~(-1)盐酸提取,用同一溶液对硒:碲进行原子荧光测定的方法,方法简便、快速、成本低、灵敏度高。硒和碲的检出限分别为8.6×10~(-10)g和2.21×10~(-10)g。 相似文献
10.
氯化亚锡还原冷蒸汽无色散原子荧光光谱法测定痕量汞,采用硫酸、双氧水、王水逐次加入低温分析样品,可以保证样品分解完全又可避免汞的损失。汞的检出限为6.0×10~(-10)g,精密度RSD％=4.1。该方法操作简便,快速、准确、费用低,可应用于大批量地球化学样品的分析。 相似文献
11.
12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area. 相似文献
13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter. 相似文献
14.
《极地研究(英文版)》2014,(3)
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied 相似文献
15.
16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet. 相似文献
17.
《山地科学学报》2014,(4)
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by 相似文献
18.
Livestock behaviour in the Pyrenees includes free grazing and a long resting period that provokes the accumulation of dung and urine in some places,so-called camping areas. The aims of this study were （i） to analyze any change in floral composition,and in nutritional and chemical contents of plants in a livestock camping area; and （ii） to relate the floral composition with soil chemical properties. In a linear transect,five sampling zones were established,from the centre of the camping area to the surrounding Nardus stricta-dominant pasture. The above ground plant biomass and the topsoil were sampled in each zone with 6 replicates per zone. Plant species were classified and weighed to calculate above ground biomass,nutritional and chemical contents,and Shannon diversity and evenness indices. Additionally,soils were sampled in two periods,at the beginning and at the end of grazing period. Soil available nutrients （nitrate,ammonium,phosphorus,potassium,calcium and magnesium）,total nitrogen,organic carbon and pH were measured.
Plant chemical contents （protein,lignin and others） were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers.
Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrien 相似文献
Plant chemical contents （protein,lignin and others） were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers.
Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrien 相似文献
19.
20.
文章概略介绍了利用卫星进行定位的原理 ;由卫星信号传播、信号接收和SA政策等引起的理论误差 ;给出了多种快速、高精度定位的工作模式和观测点选择的原则 ;列出了将WGS - 84坐标转换为我国坐标的公式及解算参数的具体方法 ,供读者在GPS工作中参考。 相似文献