关中西部滑坡的結构、构造特征及稳定性分析     

胡海濤  項式均  王肇芬  林蓬琪  陈霞 《地质学报》1965,44(4)

前言渭河北岸宝鸡、常兴间,高出河面170-190米的黃土阶地斜坡之上,不同时期、不同类型的滑坡成带分布。在98公里地段內滑坡约占81％,中、深层滑坡为数约百余个,直接影响塬边渠道工程的建设,并威胁着城镇、工厂企业和铁路交通的安全。在黃土地区其  相似文献   

Assessment of cytochrome P450 1A in harbour seals (Phoca vitulina) using a minimally-invasive biopsy approach     

Miller KA  Assunção MG  Dangerfield NJ  Bandiera SM  Ross PS 《Marine environmental research》2005,60(2):153-169

Biomarkers of organochlorine exposure, such as the induction of cytochrome P450 1A (CYP1A), can be used to assess the impact of environmental contaminants on the health of free-ranging marine mammal populations. The objective of the present study was to measure CYP1A in skin and liver biopsies obtained from live harbour seals (Phoca vitulina). Twelve harbour seal pups, aged three to five weeks, were captured from the Fraser River estuary, British Columbia, Canada, and temporarily held in captivity. Skin ( approximately 60 mg) and liver ( approximately 40 mg) biopsies, obtained while seals were under general anaesthesia, yielded sufficient tissue for the measurement of CYP1A by immunoblot analysis and ethoxyresorufin O-deethylase activity. A short-term exposure experiment, in which harbour seals (n=3) were treated orally with beta-naphthoflavone (BNF), resulted in increased hepatic and cutaneous CYP1A protein levels, consistent with observations in other mammals. This study is the first to measure CYP1A in skin and liver biopsies from live harbour seals and to report in vivo BNF-associated CYP1A induction in a marine mammal. The results demonstrate that microsamples collected using minimally-invasive techniques can provide toxicologically-relevant information form marine mammals.  相似文献   

海岸线长度与分维在不同比例尺地图上的变化研究     

朱晓华  王建  陈霞 《海洋科学进展》2001,19(4):71-75

结合国内外海岸线分形研究进展 ,以江苏省海岸线为例 ,系统地探讨了不同比例尺地图上海岸线长度与分维的变化及其规律。指出海岸线长度与地图比例尺之间存在有 lg L =algk b的基本关系 ;其次 ,对于同一条海岸线来说 ,使用量规法和网格法计算所得分维结果是不同的 ,使用量规法的计算结果大于使用网格法的计算结果 ;再者 ,在不同比例尺地图上 ,同一海岸线的分维是不同的 ,随着地图比例尺的逐渐变小 ,海岸线分维相应地逐渐变小 ,且在不同比例尺间使用量规法计算所得海岸线分维结果的差值大于使用网格法计算所得海岸线分维结果的差值  相似文献   

Carbon isotope systematics of individual hydrocarbons in hydrothermal petroleum from Escanaba Trough, northeastern Pacific Ocean     

Simoneit BR  Schoell M  Kvenvolden KA 《Organic Geochemistry》1997,26(7-8):511-515

We submitted individual aliphatic and polycyclic aromatic hydrocarbons in samples of hydrothermal petroleum from Escanaba Trough to compound specific isotope analysis to trace their origins. The carbon isotope compositions of the alkanes and polycyclic aromatic hydrocarbons (means -27.5 and -24.7%, respectively) reflect a primarily terrestrial organic matter source.  相似文献   

应用农业气候区划连续七年粮食喜获丰收     

陈霞 《贵州气象》1997,(1)

紫云苗族布依族自治县，1996年粮食总产达到98447吨，安顺地委、行署再次奖励给紫云一部小车。这是紫云战胜低温，洪涝和干旱袭击的第7个丰收年，它饱含着各级党政干部的不懈努力，也浸润着广大农业科技人员和气象科技工作者默默无闻的无私奉献。地处麻山腹地的紫云，1989年粮食总产只有55020吨，人均吃粮只有124kg，温饱——一个严峻的问题摆在人们的面前，农业科技人员义不溶辞地承担了历史赋予的使命，他们在分析研究紫云过去粮食生产低而不稳的原因时，充分应用了1980年《紫云县农业气候区划手册》提供的大量资料，总结了“一个种子打天…  相似文献   

三维储层模型的地震属性     

陈霞  李茂榕 《国外石油地质》1997,(2):35-36

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联系家乡变迁 创设学习情境     

陈霞 《地理教学》2005,(4):43

苏霍姆林斯基指出：“没有欢欣鼓舞的心情，没有学习的兴趣，学习就会成为学生的沉重负担。”课堂能否激发学生的学习兴趣，使学生有个愉悦的学习环境，更多取决于教师在课堂上创设的情境，这是学习提高学习效率的重要前提。  相似文献   

Persistent organic pollutants (POPs) in a small, herbivorous, arctic marine zooplankton (Calanus hyperboreus): trends from April to July and the influence of lipids and trophic transfer   总被引：3，自引：0，他引：3  

Fisk AT  Stern GA  Hobson KA  Strachan WJ  Loewen MD  Norstrom RJ 《Marine pollution bulletin》2001,43(1-6):93-101

Samples of Calanus hyperboreus, a herbivorous copepod, were collected (n = 20) between April and July 1998, and water samples (n = 6) were collected in May 1998, in the Northwater Polynya (NOW) to examine persistent organic pollutants (POPs) in a high Arctic marine zooplankton. Lipid content (dry weight) doubled, water content (r2 = 0.88) and delta15N (r2 = 0.54) significantly decreased, and delta13C significantly increased (r2 = 0.30) in the C. hyperboreus over the collection period allowing an examination of the role of these variables in POP dynamics in this small pelagic zooplankton. The rank and concentrations of POP groups in C. hyperboreus over the entire sampling was sum of PCB (30.1 +/- 4.03 ng/g, dry weight) > sum of HCH (11.8 +/- 3.23) > sum of DDT (4.74 +/- 0.74), sum of CHLOR (4.44 +/- 1.0) > sum of CIBz (2.42 +/- 0.18), although these rankings varied considerably over the summer. The alpha- and gamma-HCH and lower chlorinated PCB congeners were the most common POPs in C. hyperboreus. The relationship between bioconcentration factor (BCF) and octanol-water partition coefficient (Kow) observed for the C. hyperboreus was linear and near 1:1 (slope = 0.72) for POPs with a log Kow between 3 and 6 but curvilinear when hydrophobic POPs (log Kow > 6) were included. Concentrations of sum of HCH. Sum of CHLOR and sum of CIBz increased over the sampling period, but no change in sum of PCB or sum of DDT was observed. After removing the effects of time, the variables lipid content, water content, delta15N and delta13C did not describe POP concentrations in C. hyperboreus. These results suggest that hydrophobic POP (log Kow = 3.86.0) concentrations in zooplankton are likely to reflect water concentrations and that POPs do not biomagnify in C. hyperboreus or likely in other small, herbivorous zooplankton.  相似文献   

海岸线空间分形性质探讨——以江苏省为例   总被引：18，自引：2，他引：18  

朱晓华  王建  陈霞 《地理科学》2001,21(1):70-75

根据分形理论 ,借助于GIS技术的支持 ,以江苏省海岸线为例 ,对以往研究少有涉及的海岸线空间分形性质进行了初步探讨 ,包括不同比例尺下海岸线长度的分形标定、不同潮滩分界线是否具有分形性质等 ,在江苏省海岸线长度的分形标定中取得了实际应用 ,由此获得了对海岸线分形性质及其分维意义的一些深入认识。  相似文献   

用地质图数据存储的标准模型     

贝恩.  KA  谈明志 《国土资源信息化》1998,(11):25-31

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