井陉县南张村电石灰岩矿床地质特征及开发利用方向     

李英军  锁云涛  刘淑娟 《河北地质》2008,(2):10-12

南张村电石灰岩矿床具有储量大,品位高、有害杂质含量低等优点,是生产电石的优质原材料。经详查,电石灰岩规模已达中型,矿床平均品位为CaO 54．33％,MgO≤1．0％。该矿床适于露天开采,交通等配套条件良好,具有很好的开发利用前景。  相似文献   

大菱鲆的受精细胞学研究   总被引：1，自引：0，他引：1  

孙威  尤锋  张培军  许建和 《海洋科学》2005,29(12):75-80

对大菱鲆（Psetta maxima）的受精过程进行细胞学观察发现,大菱鲆从精子入卵、皮层反应、卵母细胞第二次成熟分裂排出第二极体、雌雄原核形成与融合,直到舍子进行第一次有丝分裂,与其他已经报道的硬骨鱼的受精程序基本相同。在受精的整个过程中所有观察过的受精卵都只发现一个精子形成原核,并最终与卵原核结合形成舍子,由此判断大菱鲆的受精方式是单精受精。  相似文献   

安康石煤资源特征及勘查开发建议   总被引：1，自引：0，他引：1  

陈西民  马合川  魏东  高钢锁  刘洪波  王福祥  黄自新 《陕西地质》2010,28(1):1-5,81

石煤是早古生代地层中的煤炭,它是由菌藻类等低等生物在浅海还原环境下形成的。安康石煤以高灰、高硫、低发热量为特点,规模小,伴生有益组分多,是安康重要的民用燃料。  相似文献   

青肯泡地区地下水中锶富集的水文地球化学环境特征及成因分析   总被引：2，自引：0，他引：2  

范伟  杨悦锁  冶雪艳  路莹 《吉林大学学报(地球科学版)》2010,40(2):349-355,367

锶在地下水营力作用下迁移和转化,其富集特征具有重要的水文地球化学意义,且与人类健康及生态环境密切相关,因此其分布特征及富集成因值得关注。在掌握研究区基本背景的前提下,采集地下水样品进行锶含量分析测试,刻画该区地下水中锶的质量浓度水平,研究不同空间位置、浅/深层含水层系统中锶的分布,以及与处理塘、滞洪区水样中锶分布之间的关系。分析本区锶富集的水文地球化学环境特征,在此基础上运用R-型因子分析法,结合区域地层矿物成分分析及土(粪)样锶含量测试结果,明晰该区水文地球化学环境形成的控制作用,探索锶富集的形成原因。结果显示:该区水文地球化学环境与所处干旱半干旱松嫩低平原大区域环境特征有一致性规律,区内地下水中锶富集程度较高,平均质量浓度达1.17mg/L,且锶富集成因由水岩作用和非点源污染共同控制。  相似文献   

Detecting urban warming signals in climate records     

何宇婷  贾根锁  胡永红  周自江 《大气科学进展》2013,30(4):1143-1153

Determining whether air temperatures recorded at meteorological stations have been contaminated by the urbanization process is still a controversial issue at the global scale. With support of historical remote sensing data, this study examined the impacts of urban expansion on the trends of air temperature at 69 meteorological stations in Beijing, Tianjin, and Hebei Province over the last three decades. There were significant positive relations between the two factors at all stations. Stronger warming was detected at the meteorological stations that experienced greater urbanization, i.e., those with a higher urbanization rate. While the total urban area affects the absolute temperature values, the change of the urban area (urbanization rate) likely affects the temperature trend. Increases of approximately 10% in urban area around the meteorological stations likely contributed to the 0.13℃ rise in air temperature records in addition to regional climate warming. This study also provides a new approach to selecting reference stations based on remotely sensed urban fractions. Generally, the urbanization-induced warming contributed to approximately 44.1% of the overall warming trends in the plain region of study area during the past 30 years, and the regional climate warming was 0.30℃ (10 yr)-1 in the last three decades.  相似文献   

Genetic variation of natural and cultured stocks of Paralichthys olivaceus by allozyme and RAPD     

尤锋  张培军  王可玲  相建海 《中国海洋湖沼学报》2007,25(1):78-84

Population genetics of the left-eyed flounder, Paralichthys olivaceus, including natural and cultured stocks distributed in the coastal waters near Qingdao of eastern maritime China, was analyzed in allozyme and RAPD. The results showed that among total 29 gene loci of 15 isozymes, 9 and 7 were po- lymorphic in natural and cultured stocks, respectively. The status of genetic diversity in P. olivaceus is low in terms of polymorphic loci in chi-square test and genetic departure index of Hardy-Weinberg equi- librium. More alleles in IDHP, CAT, GDH and Ldh-C allozymes were found in the fish, which could be used as markers in assortive breeding and distinguishing stock, population or species evolution. Total 88 and 86 RAPD bands ranging from 200 to 2 500 bp were recognized individually in average of 7.8–8.0 bands per primer. The genetic diversity in cultured stock is lower than that in natural ones showing an ob- viously decreasing genetic divergence. Therefore, effective countermeasures must be taken to protect ge- netic resources of marine cultured fishes. The 2 markers have their own pros and cons. Combining the 2 markers to investigate the genetic variation of populations is suggested. The results provide basic data of this flounder and they are useful for studying genetic improvement and genetic resources of the fish.  相似文献   

Preliminary study on mitochondrial 16S rRNA gene sequences and phylogeny of flatfishes （Pleuronectiformes）     

尤锋 刘静张培军  相建海 《中国海洋湖沼学报》2005,23(3):335-339

A 605 bp section of mitochondrial 16S rRNA gene from Paralichthys olivaceus, Pseudorhombus cinnamomeus, Psetta maxima and Kareius bicoloratus, which represent 3 families of Order Pleuronectiformes was amplified by PCR and sequenced to show the molecular systematics of Pleuronectiformes for comparison with related gene sequences of other 6 flatfish downloaded from GenBank. Phylogenetic analysis based on genetic distance from related gene sequences of 10 flatfish showed that this method was ideal to explore the relationship between species, genera and families. Phylogenetic trees set-up is based on neighbor-joining, maximum parsimony and maximum likelihood methods that accords to the general rule of Pleuronectiformes evolution. But they also resulted in some confusion. Unlike data from morphological characters, P olivaceus clustered with K.bicoloratus, but P cinnamomeus did not cluster with t3. olivaceus, which is worth further studying.  相似文献   

工业厂房在2008汶川大地震中的震害分析及启示     

王威  郑山锁 《地震工程与工程振动》2011,31(1):130-141

基于2008年汶川大地震中现场对工业建筑的震害调查,列举了几种典型的震害现象:(1)主体结构破坏,主要表现为屋盖扭曲或坍塌、排架柱压溃或折断、支撑拉断或压曲;(2)非结构构件震害主要表现为围护墙震害明显,特别是纵墙端开间、高大山墙、高低跨悬墙的破坏;(3)地基基础等破坏.然后,分析了不同震害的原因与特征,并提出相应设计...  相似文献   

五指山背斜纳雍枝铅锌矿地质特征及找矿前景分析①   总被引：1，自引：0，他引：1  

吴先彪  朱尤清  廖树衡  锁瑞强 《矿产与地质》2013,(1):26-31,44

纳雍枝铅锌矿床位于五指山背斜北东部,是五指山矿集区的组成部分。文章通过成矿地质背景分析、矿床成因分析以及与典型密西西比河谷铅锌矿床的对比,结合矿床地质特征,认为纳雍枝地区具有较好的找矿前景。  相似文献   

石油污染场地浅层地下水监测式自然衰减效果评价     

夏雨波  王冰  杨悦锁等 《水文地质工程地质》2013,(6):85-91

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