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Search Results: 1 - 10 of 41109 matches for " 申洪 "
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山东中新世山旺组葛属(豆科)小叶的形态及其古生态学意义
Leaflet Morphology of Pueraria (Leguminosae) from the Miocene Shanwang Formation of Shandong Province and Its Palaeoecological Implications
 [PDF]

王祺,,
Botanical Research (BR) , 2012, DOI: 10.12677/BR.2012.12003
Abstract: 葛属Pueraria是豆科蝶形花亚科、菜豆族大豆亚族中最大的、具有三小叶复叶的属,其大多数种为攀援性藤本植物,分布于东亚、南亚、东南亚和大洋洲。化石记录表明,葛属早在中新世就已出现在东亚、巴尔干半岛和高加索地区的亚热带和温带植物群中,目前已知有3个化石种,即中国山旺中新世的荚果化石山旺葛藤P. shanwangensis、山旺和日本数个中、上新世产地的叶、小叶化石鲁葛藤P. miothunbergiana以及克罗地亚和格鲁吉亚阿布哈兹中新世的小叶化石大葛藤P. maxima。本文基于对中新世山旺组最近采集的葛属小叶印痕化石的观察和对现生种葛P. montana小叶的形态比较,研究了该属化石种的小叶形态和发育变异。结果表明,现生种葛与化石种鲁葛藤和大葛藤的小叶都具有不甚发育的间二级脉,这个特征在先前报道的鲁葛藤小叶化石中未见保存。另外,它们的主脉和二级脉远轴侧有时都会分别发出两条挨得很近、角度不同的二级脉和二级脉梳脉,这个特征过去在葛属中则被忽视了。总体上,葛属小叶化石的叶脉特征在中新世广阔的欧亚中纬度地区显示了高度的相似性。目前,仅在中国中新世山旺植物群和日本中新世高峰山组植物群中发现了与现生的葛小叶相似的、具有裂瓣的鲁葛藤小叶化石,但现生葛比化石葛的小叶更大些、似乎发育了更多具有裂瓣的小叶,这可能与中新世以来大气二氧化碳浓度的变化有关。现生葛长在荫蔽生境以及攀援于支持物(如藤架或其他木本植物)上的植株比生于开阔生境以及蔓生的植株发育了更多的、具有裂瓣的小叶,这可能有效促进了整株植物的叶片和冠层中的光照截取和通风散热。据此推测,中国和日本中、上新世的鲁葛藤居群可能比克罗地亚和阿布哈兹中新世的大葛藤居群的生态耐受性更加宽泛,东亚的居群既生于荫蔽的、更多依赖森林的生境中,也长在开阔的、较少依赖森林生境中,甚至蔓生。
Pueraria DC. is the largest papilionoid legume, trifoliolate genus of the subtribe Glycininae in the tribe Phaseoleae, the majority species of which are climbing lianas distributed in East Asia, South Asia, Southeast Asia, and Oceania. The known three fossil species of Pueraria described from the subtropical and temperate floras of the Balkan Peninsula, the Caucasus, and eastern Asia respectively are P. shanwangensis (fruit) from the Miocene Shanwang of China, P. miothunbergiana (leaf and leaflet) from the Miocene of Shanwang and numerous localities in the Mio-Pliocene of Japan, and P. maxima (leaflet) from the Miocene of Croatia and Georgian Abkhazia. On the basis of observations on the newly collected Pueraria leaflet impres-sions and comparisons with the leaflets of living P. montana, the morphology and developmental variation of Pueraria leaflet fossils are studied. The result shows that the leaflets of both living species P. montana and fossil species P. miothunbergiana and P. maxima bear poorly developed intersecondary veins, which were not observed in former reports on P. miothunbergiana. Also, two adjacent secondary veins or agrophic veins at different angles are sometimes diverged respectively from the primary vein (midvein) and the exmedial side of secondary veins in both extant and fossil Pueraria leaflets, which is a feature that has long been neglected. Overall, the venation of fossil Pueraria leaflets that are widely occurred across the Miocene of middle lati-tudes in Eurasia is highly similar, but the lobed leaflets similar to those of living P. montana are only discov-ered from the Miocene Shanwang flora of China and Takamine flora of Japan. Extant P. montana bears larger leaflets than fossil Pueraria and seems to have developed more lobed leaflets than fossil P.
关于乔木状石松植物茎压印化石主要分类性状的评述
Notes on the Key Taxonomic Characters of Arborescent Lycopsid Stem Adpressions
 [PDF]

王祺,,
Botanical Research (BR) , 2013, DOI: 10.12677/BR.2013.23012
Abstract:

乔木状石松植物在晚古生代植物群中一直引人注目,是最早在中泥盆世(约393~383百万年前)就进化出两极生长、乔木和异孢习性的维管植物类群之一。本文评述了乔木状石松植物茎压印化石一些主要的分类性状以及相关术语,包括叶座、叶痕、通气道痕、叶舌和叶序。建议这些分类性状在使用中应该规范,并强调了它们的生物学和埋藏学意义。
The Late Palaeozoic arborescent lycopsids are one of the conspicuous vascular plant groups, which have developed the bipolar growth, tree and heterosporous habits since the Middle Devonian (ca. 393 - 383 million years ago). In this paper, the key taxonomic characters and relevant terminology on stem adpressions of arborescent lycopsids are reviewed. These characters include leaf cushion, leaf scar, parichnos scar, ligule, and phyllotaxy. We suggest that the taxonomic characters should be defined properly, with considerations to their biological and taphonomic implications in practice.

藏族听力残疾儿童社会适应、社会支持与生活满意度的关系研究

重庆师范大学学报(自然科学版) , 2014, DOI: 10.11721/cqnuj20140224
Abstract: 运用“听力残疾儿童社会适应行为量表”、“社会支持评定量表”和“生活满意度量表”,选择230名西藏藏族听力残疾儿童,探索多元文化背景下藏族听力残疾儿童社会适应、社会支持和生活满意度的关系模型。发现藏族听力残疾儿童社会适应行为与社会支持相关系数为0.611,与生活满意度相关系数为0.507,它们的相关性均达到显著水平。主观支持与客观支持变量联合解释社会适应行为变量51.8%的变异量,支持变量与社会适应行为变量联合解释生活满意度变量59.4%的变异量。社会支持与生活满意度不存在直接效果,而是通过社会适应行为这一中介变量间接地对“生活满意度”产生效应。社会支持可以有效地促进个体社会适应行为的发展,社会适应行为的发展可以提升个体的生活满意度。
基于intelrng的真随机数生成器研究
黄枫,
南方医科大学学报 , 2004,
Abstract: 目的构建基于特定intel芯片组中randomnumbergenerator(rng)单元的真随机数生成器。方法在intel815e芯片组的个人电脑上安装intelsecuritydriver(isd)后,使用microsoftvisualc++6编程,通过寄存器读取的方式获取rng中的随机数。结果生成的500个随机数通过的nistfips140-1和χ2拟合优度检验(α=0.05),表明本方法所生成的随机数满足独立性和分布均匀性的要求。生成7500个随机数经域值变换后与随机数表中的同等数目的随机数进行了统计学比较,结果显示前者的均值偏移、sd,se和cv均小于后者。结论基于intelrng的真随机数生成器可以生成满足独立性和分布均匀性的真随机数,生成的随机数效果与随机数表中的随机数没有显著性区别。但是基于intelrng的真随机数生成器能解决使用随机数表获取随机数中可能存在的问题,具有较好的普遍性和实用性。
基于高度角加权的伪卫星定位线性化误差评估方法
A Linearization Error Evaluation Method of Pseudolite Positioning Based on Weighted Elevation Angle
 [PDF]

霍翠萍, 李子,, 周凯
Geomatics Science and Technology (GST) , 2016, DOI: 10.12677/GST.2016.41001
Abstract: 与其他基于测距进行定位解算的导航系统(如GPS)一样,伪卫星定位系统观测模型在本质上是非线性的,对观测模型进行线性化对于大部分定位算法是一个必不可少的过程,而与GPS等卫星导航系统不同的是,伪卫星距离用户较近,其模型线性化时产生的误差不能被忽略,否则会导致定位解算可能无法正确收敛。针对此问题,本文精确地给出了线性化误差的边界值,并提出了判别线性化误差对定位精度影响的简化方法,根据此方法分析了不同伪卫星的星座布局对伪卫星系统线性化误差的影响。通过仿真对所提出的伪卫星的线性化误差评估的方法进行了验证。结果表明,当伪卫星系统满足判定条件时,迭代结果一定会收敛,而不满足时,则不一定收敛。
Like the other navigation systems which are calculating positioning based on ranging, such as GPS, the observation model of pseudolite positioning system is essentially nonlinear. For most posi-tioning systems, linearization of the observation model is an essential process. Since the distances between the user and pseudolites are close compared with GPS and other satellite navigation sys-tems, the linearization error of the model cannot be ignored. Otherwise it may lead to incorrect convergence of the positioning solution. To solve this problem, this paper gives a precise boundary value of the linearization error. What’s more, it also gives a simplified method to judge the impact of the linearization on the positioning accuracy, based on which, impacts of different pseudolite constellation layouts on linearization error are analyzed. And then, it verifies the proposed assessment method of the linearization error of pseudolites by simulation. The results show that when the pseudolite systems satisfy the condition, results of the iteration will converge, otherwise, they are not necessarily converge.
广东南部地理景观中土壤重金属垂直分异及其地球化学分层性
继华,
地理研究 , 1988, DOI: 10.11821/yj1988040003
Abstract: 本文研究热带亚热带土壤中重金属分布的垂直分异及其分层性特征.土壤剖面中,水溶态、可交换态和有机结合态的重金属浓度自上层向底层降低.水溶态和有机结合态重金属的分布与有机质一致,而与pH值相反.Fe-Mn氧化物结合态的重金属分布与粘粒一致.残渣态分布的差异极小.
我国热带和南亚热带一些土壤中汞分布特征的初步研究
继华,
地理研究 , 1983, DOI: 10.11821/yj1983010009
Abstract: 本文报导我国热带和南亚热带一些土壤中汞的分析结果,并讨论了土壤中汞的含量水平,汞在土壤剖面中以及在景观地球化学系列各单元景观土壤中的分布特征。
川藏公路田妥一怒江段某滑坡稳定性分析与整制
登科,
重庆交通大学学报(自然科学版) , 2011, DOI: 10.3969/j.issn.1674-0696.2011.supp1.032
Abstract: :?结合国道318线川藏公路田妥一怒江段K3668+700~K3668+790滑坡的基本状况,对滑坡的成因进行了分析。对K3668+715断面建立了有限元分析模型,利用有限元强度折减法,计算分析了该段滑坡在重力场和地震作用下的稳定性,计算分析求得该滑坡整治前在重力场和地震作用下的稳定安全系数分别为0.99和0.93,滑坡处于不稳定的滑动状态,应及时对该段滑坡进行整治。提出了合理的整治方案并进行了安全性评价,结果表明整治后滑坡的安全系数大于设计安全系。
循环流化床烟气脱硫系统控制技术
,
环境工程 , 2012, DOI: 10.13205/j.hjgc.201202018
Abstract: 阐述了循环流化床烟气脱硫系统电气控制的内容、方法、仪表等技术。根据循环流化床烟气脱硫实验系统温度、压力、流量的测量,实现了该系统闭环开环自动、手动控制的功能,并且根据实验室的具体情况,采取特殊技术方式,完成实验自动化的控制。该控制技术对扩大到实际工程应用具有指导意义。
CH2=CHCl与O(3P)反应的理论研究
胡武,
化学学报 , 2005,
Abstract: 用量子化学密度泛函理论和QCISD(Quadraticconfigurationinteractioncalculation)方法,对O(3P)与CH2CHCl的反应进行了理论研究.在UB3LYP/6-311++G(d,p),UB3LYP/6-31++G(3df,3pd)计算水平上,优化了反应物、产物、中间体和过渡态的几何构型,并在UQCISD(T)/6-311++G(2df,2pd)水平上计算了单点能量.为了确证过渡态的真实性,在UB3LYP/6-311++G(3df,3pd)水平上进行了内禀坐标(IRC)计算和频率分析,并确定了反应机理.研究结果表明,反应主要产物为CH2CHO和Cl.
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