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1.
The authors derive a formula for the volume of a compact domain in a symmetric space from normal sections through a special submanifold in the symmetric space.This formula generalizes the volume of classical domains as tubes or domains given as motions along the submanifold.Finally,some stereological considerations regarding this formula are provided.  相似文献   
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This paper describes the resources, scientific spaces, and experts involved in the study of a mass poisoning caused by the drinking of arsenic-contaminated wine exported from Spain to France in 1932. Local and international periodicals record the poisoning of 300 French sailors, and stressed the commercial implications of the case. We discuss the reports prepared by different experts (mainly physicians, agricultural engineers, and customs chemists). Their work was not limited to preparing technical publications or chemical analyses; they also actively defended the quality of their local wine, and played a major role in the discussions regarding the regulation of the international wine market in the 1930s, when new standards regarding the analysis of wine were being considered. Curiously, this well-publicised case of mass poisoning did not have any noticeable consequences in the international regulation of wine. This absence of subsequent regulatory action and the role of experts are central topics of the paper.  相似文献   
3.
Classical problems in integral geometry and geometric probability involve the kinematic measure of congruent segments of fixed length within a convex body in R3. We give this measure from rotational formulae; that is, from isotropic plane sections through a fixed point. From this result we also obtain a new rotational formula for the volume of a convex body; which is proved to be equivalent to the wedge formula for the volume.  相似文献   
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Journal of Solid State Electrochemistry - The application of the voltammetry of microparticles methodology to the study of gildings in paintings and architectural ornaments is described....  相似文献   
6.
In order to get further insight on the Weyl’s formula for the volume of a tubular hypersurface, we consider the following situation. Letc(t) be a curve in a space formM λ n of sectional curvature λ. LetP 0 be a totally geodesic hypersurface ofM λ n throughc(0) and orthogonal toc(t). LetC 0 be a hypersurface ofP 0. LetC be the hypersurface ofM λ n obtained by a motion ofC 0 alongc(t). We shall denote it byC PorC Fif it is obtained by a parallel or Frenet motion, respectively. We get a formula for volume(C). Among other consequences of this formula we get that, ifc(0) is the centre of mass ofC 0, then volume(C) ≥ volume(C),P),and the equality holds whenC 0 is contained in a geodesic sphere or the motion corresponds to a curve contained in a hyperplane of the Lie algebraO(n−1) (whenn=3, the only motion with these properties is the parallel motion). Work partially supported by a DGES Grant No. PB97-1425 and a AGIGV Grant No. GR0052.  相似文献   
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LetM be a complex submanifold in . We define the total curvatures ofM and we get a local interpretation of them. Finally, we give a topological characterization for the total (non-absolute) curvature of complex hypersurfaces in .Partially supported by Fundació Caixa Castelló grant n. MI25043/92.Partially supported by the Spanish DGICYT grant #PB91 — 0324.  相似文献   
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A surface area estimator for three-dimensional convex sets, based on the invariator principle of local stereology, has recently motivated its generalization by means of new rotational Crofton-type formulae using Morse theory. We follow a different route to obtain related formulae which are more manageable and valid for submanifolds in constant curvature spaces. As an application, we obtain a simplified version of the mentioned surface area estimator for non-convex sets of smooth boundary.  相似文献   
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为获得甜叶菊的最佳增殖培养基以及60 Co-γ辐射诱变育种的剂量,以无菌甜叶菊茎段为外植体,采用正交实验对其增殖培养基的激素种类和浓度进行优化;在此基础上,分别采用5、15、30、60、90、120和150Gy剂量的60Co-γ射线对甜叶菊茎段进行辐照诱变,每隔15d记录其生长情况,统计死亡率;并测定≤30Gy剂量处理的叶片中可溶性多糖和可溶性蛋白质的含量。结果表明,甜叶菊茎段增殖的最佳培养基为MS+NAA 0.5mg·L-1+TDZ0.1mg·L-1+6-BA 1.0mg·L-1。60 Co-γ射线诱变的半致死剂量(LD50)为24Gy,处理后的甜叶菊外观呈现显著差异,随着辐射剂量的增强,30d后甜叶菊死亡率分别为1.7%,2.4%,20.5%,92.7%,98.9%,99.4%,100%,辐射剂量是5、15、30Gy时,可溶性多糖含量较对照组分别增加76.77%,26.73%,15.29%,表明辐照诱变导致甜叶菊试管苗短期的应激效应。研究结果为甜叶菊的辐照诱变育种提供了理论参考。  相似文献   
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