首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9篇
  免费   0篇
废物处理   1篇
综合类   1篇
基础理论   5篇
污染及防治   2篇
  2015年   2篇
  2014年   1篇
  2013年   1篇
  2011年   1篇
  2005年   1篇
  1991年   1篇
  1986年   1篇
  1973年   1篇
排序方式: 共有9条查询结果,搜索用时 31 毫秒
1
1.
In utero sonographic diagnoses from forty-five malformed infants were correlated with their autopsy findings. Fifty-two malformations were diagnosed prenatally in 42 of the patients but 90 additional malformations were not. Nine sonographically diagnosed abnormalities were not confirmed at autopsy. Factors compromising sonographic diagnosis included: limited examinations, small fetal size, timing of examination, oligohydramnios, fetal position, nature of the malformation and unfamiliarity of the ultrasonographer with specific malformation syndromes. In vitro ultrasonography is an invaluable tool of diagnosing congenital malformations but has limitations.  相似文献   
2.
3.
4.
The first synthesis of syn and anti 12-hydroxylated derivatives of endrin (and thence 12-ketoendrin) has been accomplished in three steps starting from hexachlorocyclopentadiene and 7-benzoyloxy [2.2.1]hepta-2,5-diene.  相似文献   
5.
ThepracticaluseofAzotobacterchroococcumasbiofertilizer hasbeenincreasinglyidentifiedinrecentyears.Oftentheefficacy ofthesebacteriaisassessedonthebasisofcropresponseswithout knowingthesurvival,persistenceandcompetitiveabilityofthein troducedstrain.Inoculat…  相似文献   
6.
Jellyfish are increasingly topical within studies of marine food webs. Stable isotope analysis represents a valuable technique to unravel the complex trophic role of these long-overlooked species. In other taxa, sample preservation has been shown to alter the isotopic values of species under consideration, potentially leading to misinterpretation of trophic ecology. To identify potential preservation effects in jellyfish, we collected Aurelia aurita from Strangford Lough (54o22′44.73″N, 5o32′53.44″W) during May 2009 and processed them using three different methods prior to isotopic analysis (unpreserved, frozen and preserved in ethanol). A distinct preservation effect was found on δ15N values: furthermore, preservation also influenced the positive allometric relationship between individual size and δ15N values. Conversely, δ13C values remained consistent between the three preservation methods, conflicting with previous findings for other invertebrate, fish and mammalian species. These findings have implications for incorporation of jellyfish into marine food webs and remote sampling regimes where preservation of samples is unavoidable.  相似文献   
7.
Twenty years of waste disposal operations at the Conservation Chemical Company (CCC) site in Kansas City, Missouri, led to contamination of soils and groundwater on a six-acre site. As a result of this contamination, the site was listed on the federal government's National Priorities List. Following extensive litigation initiated in 1982, more than 200 contributors to the site (Potentially Responsive Parties or PRPs), CCC's insurance companies, and the government ultimately reached a settlement to fund the remedial action. The remedy that was agreed upon included: (1) a permeable cap to allow water intrusion to assist groundwater cleanup; (2) a with drawal well system to achieve an inward groundwater gradient; and (3) a groundwater treatment system employing several unit operations. Containment of the contaminated plume relied on hydraulic, rather than structural, containment to prevent mitigation of contaminants from the site. ABB Environmental Services, Inc. (ABB-ES) was retained to perform treatability tests and to design, construct, and start up the groundwater treatment plant after the installation of the permeable cap by others.  相似文献   
8.
9.
Accurate field data on trophic interactions for suspension feeders are lacking, and new approaches to dietary analysis are necessary. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was integrated with stable isotope analysis to examine dietary patterns in suspension-feeding Mytilus spp. from seven spatially discrete locations within a semi-enclosed marine bay (Strangford Lough, Northern Ireland) during June 2009. Results of the two methods were highly correlated, reflecting dietary variation in a similar manner. Variation in PCR-DGGE data was more strongly correlated with the principal environmental gradient (distance from the opening to the Irish Sea), while values of δ 13C and δ 15N became progressively enriched, suggesting a greater dependence on animal tissue and benthic microalgae. Diatoms and crustaceans were the most frequently observed phylotypes identified by sequencing, but specific DNA results provided little support for the trophic trends observed in the stable isotope data. This combined approach offers an increased level of trophic insight for suspension feeders and could be applied to other organisms.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号