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Development of an Enzyme Immunoassay for the Detection of Mecoprop in Drinking Water and Groundwater Based on Antibodies Raised in Chicken Egg Yolk Antibodies against mecoprop were isolated from egg yolk of immunized hens and were used for the development of an enzyme-linked immunosorbent assay. We tested assay parameters (pH and concentration of buffer, incubation temperature, kind of enzyme tracer) to optimize the standard curve for mecoprop. By decreasing the pH, the detection limit was reached at a concentration of 0.35 μg/L mecoprop. The concentration for 50% inhibition (50% B/B0) was 2.8 μg/L. Dichlorprop and the methyl esters of both mecoprop and dichlorprop showed high crossreactivity (165%, 400% and 233%). Antibodies against mecoprop separated from egg yolk were compared to antibodies raised in rabbit for both sensitivity and specificity. Chicken immunoglobulins were found to be less sensitive and specific than the mammalian IgG's.  相似文献   
2.
Modelling of uplift histories in the Upper and Middle Thames valleys has revealed an important difference, in the form of additional early post-Anglian uplift in the Middle Thames, attributed to an Anglian (~ 440 ka) glacio-isostatic effect. Terraces in the Upper Thames around Oxford seem unaffected by glacio-isostasy and their heights show regional uplift of ~ 35–40 m since the Anglian. The result of the glacio-isostasy is that Anglian terraces are significantly higher above the valley floor in the Middle Thames (up to 55 m) than in the Upper Thames. Recognition of this displacement of Middle Thames terraces has solved long-standing problems of correlation between this area and the Upper Thames: the pre-Anglian (Cromerian Complex) age of the Sugworth Channel deposits, indicated by biostratigraphy, is no longer a difficulty, whereas the Hanborough Terrace is now thought to be of Anglian age, albeit incorporating pre-Anglian faunal remains and perhaps with a significant early post-Anglian component. These findings have implications for the understanding of the effects of Middle Pleistocene glacio-isostasy and of landscape evolution on the periphery of glaciated regions.  相似文献   
3.
‘Triconodonts’ are relatively rare in the new Purbeck Limestone Group mammal fauna, especially in comparison with the finds made in the nineteenth century in the same beds. However, besides some remains of the already known Triconodontidae, a new possible morganucodontan of uncertain familial affinities, Purbeckodon batei gen. et sp. nov., has been discovered, extending considerably the chronological range of the order while constituting another testimony to the vitality and diversity of Mesozoic mammals.  相似文献   
4.
在红嘴子首次发现猛犸象等哺乳动物化石和石核、石片及刮削器等旧石器。其中刮削器为目前吉林省境内发现最好的两刃刮削器。旧石器和猛犸象等哺乳动物化石一起出土,表明其地质时代为晚更新世,文化时代为旧石器时代晚期。该发现证明早在1~4万年前长春地区就有古人类活动。为在该区寻找古人类化石和古文化遗存提供了佐证,对研究当地第四纪气候、古地理也有一定的意义。  相似文献   
5.
Mammals are the most important elements in Cenozoic terrestrial ecosystem. The composition and the character of a mammalian fauna are controlled by evolution time and evolutionary rate. Here we took 50 Asian Paleogene mammalian faunas as representatives and applied Bayesian Tip-dating method to infer the relationships and divergence times among these faunas.Based on the results of Bayesian Tip-dating analyses, we discussed the correlation between the paleogeographic changes and the mammalian fauna turn-overs. Compared with the traditional fauna correlation and sorting, Bayesian Tip-dating analyses revealed more detailed similarities reflected via the divergence times among the 50 faunas. We discovered that the early Eocene mammalian fauna, which firstly appeared in India subcontinent, is similar to the faunas of the same age in other parts of Asia. It is likely that a passage for the mammalian dispersal was formed before early Eocene. Bayesian inferring suggests that the first appearance of the dispersal passage is during 64.8–61.3 Ma. This time window is close to the time estimation for the initial time of India-Asia collision. During 57.1–47.2 Ma, India subcontinent probably had a habitat different from the main part of Asia, as it was reflected from the composition of the mammalian faunas. It is probably correlated with the uplifted Gangdese Mountain and shallow seas and lowlands on both sides of the collision region. The very remote divergence time(64.8 Ma) estimated by Bayesian inferring reflects the mammalian fauna turnover during the Eocene-Oligocene transition, obviously affected by the global cooling. Till the end of Oligocene, the Arabic Peninsula and Asian mainland remained separated and the mammalian faunas did not show clear connection.  相似文献   
6.
二连盆地下古近系的磁性地层学研究   总被引:7,自引:0,他引:7  
古地磁的测试结果表明,蒙古高原二连盆地努和廷勃尔和与呼和勃尔和地区剖面早古近纪地层共记录了5个正极性段与6个负极性段,通过与2004年标准极性年代表对比,确认其可与C21r-C26r之间的极性带对应。脑木根组以晚古新世沉积为主,同时接受了始新世最早期部分沉积及少许中古新世;阿山头组跨越了早—中始新世,持续时间较长;伊尔丁曼哈组的时代为中始新世。同时,确定了含Lambdopsalis,Prionessus及Palaeostylops的化石层的时代为晚古新世最早期;Gomphos层的年龄大致与古新世-始新世界线的年龄相当。  相似文献   
7.
童永生  王元青李茜 《地质论评》2006,52(2):153-162,i0002
岭茶地区的古近纪地层常称为栗木坪组或岭茶组。根据哺乳动物化石、地层特征和新近的古地磁和碳同位素研究成果,本文将岭茶地区的古近纪地层分为上古新统栗木坪组和下始新统岭茶组。岭茶组典型剖面,可选在成家冲东北的岭茶—霞流公路旁。由于底部出现碳同位素负向漂移,是目前中国可确定的始新统/古新统界线。在中国早始新世哺乳动物中首次出现的哺乳动物有奇蹄类、偶蹄类、真正的灵长类和梳趾鼠类型的啮齿类,并有许多首现的属。根据哺乳动物群组成特征,将中国早始新世哺乳动物群分为两个组合带:以李官桥盆地大尖动物群为代表的岭茶晚期的犀貘一菱臼兽组合带(Heptodon--Rhombomylus Assemblage Zone)和以衡阳盆地岭茶动物群为代表的岭茶早期的始祖貘一软食中兽组合带(Homogalax--Hapalodectes Assemblage Zone)。  相似文献   
8.
西宁-民和盆地上第三系十分发育,皆为中新统陆相红层。该统自下而上划分为谢家组、车头沟组、咸水河组和“临夏组”,每组分为二个岩性段。含哺乳动物化石28属37种,介形虫化石15属43种,轮藻化石7属10种及3个孢粉组合;最大出露厚度1595.85m。该统与渐新统马哈拉沟组整合接触,其上被第四系不整合覆盖。哺乳动物呈草原型鼠兔类为主→草原型鼠类与森林型长鼻类、鹿类混生→森林型长鼻类等大量出现并伴生鼠兔类→草原型三趾马动物群的群体演化特征。介形虫为古中国大陆生物区中新世常见属种,轮藻为我国第三纪常见组合;孢粉为草原—森林型组合。  相似文献   
9.
中国黄土磁性地层与生物地层对比   总被引:2,自引:0,他引:2  
本文统计了中国黄土地层中发现的哺乳动物化石并对一些发现较丰富哺乳动物化石的黄土剖面进行了磁性地层学研究,分析了磁性地层与生物地层对比结果,讨论了黄土层中哺乳动物化石的时空分布,以及有关气候环境问题。  相似文献   
10.
兰州盆地晚中新世保德期哺乳动物化石新发现   总被引:1,自引:0,他引:1  
张行 《甘肃地质》1993,2(1):1-5,T001
在永登县中堡镇邢家湾一带发现的晚第三纪保德期哺乳动物化石计有1科5属3种,它可与甘肃东部、西部动物群对比。  相似文献   
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