首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
西藏嵩草属(莎草科)的修订   总被引:5,自引:0,他引:5  
在标本观察和野外调查的基础上,对西藏的嵩草属Kobresia植物进行了分类学修订,共确认了36种和1亚种。更正了6个类群的学名,它们正确的名称是K. esenbeckii,K. fissiglumis,K. gammiei,K. littledalei,K. myosuroides ssp. bistaminata和K. vaginosa。有13个名称,即K. angusta,K. cercostachys var. capillacea,K. clarkeana,K. curticeps var. gyirongensis,K. deasyi,K. glaucifolia,K. hookeri,K. nudicarpa,K. prainii var. elliptica,K. seticulmis,K. stenocarpa,K. stenocarpa var. simplex和K. williamsii处理为异名,其中K. prainii var. elliptica,K. glaucifolia和K. stenocarpa var. simplex为新异名。发现了西藏分布的一个新记录种密穗嵩草K. handel-mazzettii。还收录了最近发表的假钩状嵩草K. pseuduncinoides和阔鳞嵩草K. woodii。此外,重新编制了西藏嵩草属分种和亚种检索表,并较为详细地登记了各类群在西藏的分布地点。  相似文献   

2.
对Breuning(1956)提出的Glenea fainanensis 种团重新进行了研究,并为G.fainanensis,G.inlineata和G.subregularis指定了选模.两个种的地位得到了订正:G.inlineata Pic star.nov.由种下地位G.fainanensis v.inlineata Pic,1943提升为种级阶元,G.subregularis Pic stat.nov.由种下地位G.internedivisa v.subregularis Pic,1943提升为种级阶元.G.tenuivittata Gressitt,1951被确认为G.subregularis Pic的新异名.编制了上述3个种的检索表、给出了成虫整体彩色照片和外生殖器照片.  相似文献   

3.
在标本室研究和野外考察的基础上,对中国野青茅属Deyeuxia的一些种类进行了修订.归并了2个名称,即将Deyeuxia sikangensis Keng并入D. scabrescens (Griseb.) Munro ex Duthie作为异名; 将D. levipes Keng并入D. nivicola Hook. f. 作为异名.确认了D. dispar L. Liou和D. agrostioides L. Liou是两个未合格发表的名称,将前者归并于D. scabrescens,后者归并于D. diffusa Keng.  相似文献   

4.
安徽大别山粒毛盘菌初探   总被引:3,自引:2,他引:1  
陈辉  叶明  谭炜 《生物学杂志》2008,25(1):26-27,8
大别山区森林植物极其丰富多样,区内气候温暖湿润,为粒毛盘菌等腐生真菌生长提供了丰富的基物和适宜的气候条件.对该地区粒毛盘菌等相关类群资源进行了研究,报道了粒毛盘菌属7个分类单元,包括Lachnum ciliare,L. nudipes,L.pudibundum,L.ptgmnaeum,L.subpygmaeum,L.sichuanense和L.virgineum,利用物种描述式表明了种的主要特征,并对其中部分种进行了形态学方面的讨论.  相似文献   

5.
报道了中国野牡丹科Melastomataceae尖子木属Oxyspora一新记录种——柑叶尖子木O. curtisii King,并绘制了特征线条图。另基于花序和花特征的不同, 将翅茎异形木Allomorphia eupteroton Guillaumin var. teretipetiolata C. Y. Wu & C. Chen由变种提升为种, 归入尖子木属, 即翅茎尖子木Oxyspora teretipetiolata (C. Y. Wu & C. Chen) W. H. Chen & Y. M. Shui, 并补充描述了其花部特征。通过扫描电镜观察了它们的花粉和种子形态, 为分类处理提供了佐证。  相似文献   

6.
对中国海鼓虾科角鼓虾属系统分类进行了研究.角鼓虾全世界共记录34种,其中中国海记录了9种.本文中记录中国海分布的角鼓虾属Athanas 8种,其中对中国海2新纪录种A.polymorphus Kemp和A.squillophilus Hayashi,进行了描记,并提供了中国角鼓虾种检索表.在中国的材料中:A.japonicus、A.ohsimai、A.polymorphus及A.squillophilus 4种的螯足表现了多态性,A.ohsimai和A.squillophilus的螯足多态性也是首次发现和记载.所有研究测量标本均保存在中国科学院海洋研究所.  相似文献   

7.
讨论了基于LED和荧光灯光源以及有无紫外线光谱的动态光照明的分类和应用.介绍了基于荧光灯的动态光照明历史.并讨论了发光二极管技术应用于动态光照明的原因.综述了动态光照影响人体皮质醇,褪黑素,警觉性,体温和情绪的作用机理.并介绍紫外线照射的安全标准.提出了一种理想的动态光照明,此种动态光考虑显色指数,色温,光照度,光谱结构和动态变化.  相似文献   

8.
中国玉兰属两新种   总被引:7,自引:0,他引:7  
描述了中国木兰科玉兰属两新种,奇叶玉兰(Yulania mirifolia D.L.Fu,T B Zhao etZ.X.Chen,sp.nov.)和青皮玉兰(Yulania viridula D.L.Fu,T B Zhao et G.H.Tian,sp.nov.)的形态特征和分布情况,并与近缘种进行了比较。  相似文献   

9.
一类周期种群系统的稳定性分析及最优控制问题   总被引:2,自引:0,他引:2  
本文讨论了一类线性时变周期种群系统的稳定性和最优控制问题.利用Lyapunov函数.对系统的稳定性进行了分析.给出了系统稳定的充分条件.并且利用Banach空间理论,证明了最优收获控制的存在性和唯一性.并且给出了最优控制所满足的必要性条件.  相似文献   

10.
直角步甲属Orthogonius Macleay在不丹和锡金原记录仅1种,即卵直角步甲O.opacus Schmidt-Gobel,本文补充了该种的一些分布记录,并描述了产自不丹和锡金的直角步甲属3新种,即喜直角步甲O.himalayicus sp.nov.、杜氏直角步甲O.dureli sp.nov.和长茎直角步甲O.longiphallus sp.nov.,给出了该地区直角步甲属分种检索表.  相似文献   

11.
一类非线性非局部反应扩散方程奇摄动问题   总被引:37,自引:4,他引:33  
本文研究了一类具有非线性非局部反应扩散方程奇摄动问题。在适当的条件下,利用微分不等式理论,讨论了问题解的渐近性态。  相似文献   

12.
非线性种群反应扩散系统的奇摄动   总被引:1,自引:0,他引:1  
研究了一类具有非线性种群反应扩散系统奇摄动问题,在适当的条件下,利用微分不等式理论,讨论了问题解的存在性和渐近性态.  相似文献   

13.
Suppose measurements of a particular feature are collected at baseline and at a number of subsequent time points and that for each individual there is a roughly linear trend in time. This paper takes three approaches to testing whether there is a relation between the initial value and the slope. It also considers whether the initial value for an individual is a useful predictor of the slope for that individual. The problems are formulated in terms of regression models with random coefficients. The solutions are illustrated using data from an observational study of clinical correlates of disability and progression in Huntington's disease.  相似文献   

14.
本文研究人口问题中的一广义扩散模型考虑它的初边值问题,证明了问题整体吸引子的存在性。  相似文献   

15.
Summary A simple method of solution is highlighted for solving a class of bioreaction-diffusion problems. By virtue of the proposed transformation the original boundary value problem is rendered into an equivalent initial value problem. Results are comparable to conventional methods, and have lower computational time requirements.NCL Communication. No. 5179  相似文献   

16.
An S-system is a set of first-order nonlinear differential equations that all have the same structure: The derivative of a variable is equal to the difference of two products of power-law functions. S-systems have been used as models for a variety of problems, primarily in biology. In addition, S-systems possess the interesting property that large classes of differential equations can be recast exactly as S-systems, a feature that has been proven useful in statistics and numerical analysis. Here, simple criteria are introduced that determine whether an S-system possesses certain types of symmetries and how the underlying transformation groups can be constructed. If a transformation group exists, families of solutions can be characterized, the number of S-system equations necessary for solution can be reduced, and some boundary value problems can be reduced to initial value problems.  相似文献   

17.
Isothermal titration calorimetry (ITC) produces a differential heat signal with respect to the total titrant concentration. This feature gives ITC excellent sensitivity for studying the thermodynamics of complex biomolecular interactions in solution. Currently, numerical methods for data fitting are based primarily on indirect approaches rooted in the usual practice of formulating biochemical models in terms of integrated variables. Here, a direct approach is presented wherein ITC models are formulated and solved as numerical initial value problems for data fitting and simulation purposes. To do so, the ITC signal is cast explicitly as a first-order ordinary differential equation (ODE) with total titrant concentration as independent variable and the concentration of a bound or free ligand species as dependent variable. This approach was applied to four ligand-receptor binding and homotropic dissociation models. Qualitative analysis of the explicit ODEs offers insights into the behavior of the models that would be inaccessible to indirect methods of analysis. Numerical ODEs are also highly compatible with regression analysis. Since solutions to numerical initial value problems are straightforward to implement on common computing platforms in the biochemical laboratory, this method is expected to facilitate the development of ITC models tailored to any experimental system of interest.  相似文献   

18.
The completely symmetrical system is defined as having identical transfer coefficients between pairs of compartments and the same loss coefficient for each compartment. The eigenvalues and eigenvector are explicitly found along with the inverses of the system matrix and the matrix of eigenvectors. Many properties, special instances of more general theorems, can be seen at once from the explicit analytic solution of the initial value, washout and washin problems. The system serves as a known case for testing estimation procedures, algorithms for solutions of linear systems, eigenvalue-eigenvector and inversion routines and is of considerable tutorial value.  相似文献   

19.
The purpose of this paper is twofold: first, to review analytical, experimental, and numerical methods for studying the nonlinear, pseudoelastic behavior of membranes of interest in biomechanics, and second, to present illustrative examples from the literature for a variety of biomembranes (e.g., skin, pericardium, pleura, aneurysms, and cells) as well as elastomeric membranes used in balloon catheters and new cell stretching tests. Although a membrane approach affords great simplifications in comparison to the three-dimensional theory of nonlinear elasticity, associated problems are still challenging. Computer-based methods are essential, therefore, for performing the requisite experiments, analyzing data, and solving boundary and initial value problems. Emphasis is on stable equilibria although material instabilities and elastodynamics are discussed.  相似文献   

20.
The purpose of this paper is twofold: first, to review analytical, experimental, and numerical methods for studying the nonlinear, pseudoelastic behavior of membranes of interest in biomechanics, and second, to present illustrative examples from the literature for a variety of biomembranes (e.g., skin, pericardium, pleura, aneurysms, and cells) as well as elastomeric membranes used in balloon catheters and new cell stretching tests. Although a membrane approach affords great simplifications in comparison to the three-dimensional theory of nonlinear elasticity, associated problems are still challenging. Computer-based methods are essential, therefore, for performing the requisite experiments, analyzing data, and solving boundary and initial value problems. Emphasis is on stable equilibria although material instabilities and elastodynamics are discussed.  相似文献   

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