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动物学报 2008年第4期54卷 602-614页

作者： Josef RAJCHARD Vít FRIDRICHOVSKY olga krivkov Jana NAVRTILOV University of South Bohemia Faculty of Agriculture Department of Biological Disciplines University of South Bohemia Faculty of Agriculture Department of Agroecology Academy of Sciences Institute of Botany Department of Plant Ecology

1999-2003年,在捷克共和国特布盆地生物圈保护区(Tebo Basin Biosphere Reserve)内,我们对13个采矿后形成的人工湖中水鸟群落的形成过程进行了研究。我们假定生活在邻近鱼塘中的水鸟会逐渐向这些人工湖迁移和聚集。在这些人工湖中共记录... 详细信息

1999-2003年,在捷克共和国特布盆地生物圈保护区(Tebo Basin Biosphere Reserve)内,我们对13个采矿后形成的人工湖中水鸟群落的形成过程进行了研究。我们假定生活在邻近鱼塘中的水鸟会逐渐向这些人工湖迁移和聚集。在这些人工湖中共记录到42种水鸟,隶属于10个目,其中17种典型的海滨鸟类是该群落的重要组成部分。这些水鸟的季节动态过程与各物种自身的生活史阶段有关(如筑巢、迁徙),同时也被人类的采矿活动所影响。环境因素和人类干扰影响了绿头鸭(Anas platyrhynchos)、疣鼻天鹅(Cygnus olor)和凤头(Podiceps cristatus)等优势种的分布。沙坑湖作为一种独特的生境为本保护区的濒危物种提供了栖息地,如:小苇(Ixobrychus minutus)、大苇莺(Acrocephalus arundinaceus)及其它潜在分布的鸟类。对南波西米亚地区沙坑湖鸟类的研究,可为其它相似地区水鸟群落演替研究提供了重要经验。

关键词：水鸟沙坑湖分布筑巢

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Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

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Journal of Renewable Materials 2018年第7期6卷 697-706页

作者： Hynek Beneš Aleksandra Paruzel JiříHodan olga Trhlíková Institute of Macromolecular Chemistry AS CR v.v.i.Heyrovsky Sq.216206 Prague 6Czech Republic

In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified bymeans of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convertpolycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composeduniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They weresuccessfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes(PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature rangingfrom 44°C to 53°C, the hardness value from 46 to 61 Shore D and the beneficial low water absorption (0.4-0.5wt.%). The PU network structure was highly influenced by the presence of aromatic structures ofpolycarbonate-units and fatty acid compositions. A suitable selection of natural oil thus enabled to adjustthermo-mechanical properties and promote excellent optical transparency of the produced PU.

关键词： Natural oil cast polyurethane bio-based polycarbonate waste recycling

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Morphological characteristics of blood cells in monitor lizards:is erythrocyte size linked to actual body size?

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Integrative Zoology 2013年第1期8卷 39-45页

作者： Petra FRÝDLOVÁ Jan HNÍZDO Lenka CHYLÍkovÁ olgaŠIMkovÁ Veronika CIKÁNOVÁ Petr VELENSKÝ Daniel FRYNTA Department of Zoology Charles University in PraguePragueCzech Republic Animal Clinic PragueCzech Republic Prague Zoo PragueCzech Republic

Blood cell morphology and count are not uniform across ***,between-species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa,and this finding was interpreted in the context of the metabolic *** the present study,we examined the numbers and the size of blood cells in 2 species of monitor lizards,the mangrove-dwelling monitor(Varanus indicus)and the savannah monitor(***),and we compared these traits in individuals of different body *** results revealed that during the course of ontogeny,the size of red blood cells increases with body *** the mass-specific metabolic rate decreases with body size and the cell volume-to-surface ratio decreases with the cell size,changes in the erythrocyte size might be the result of oxygen transport adjustment.

关键词： blood parameters body size erythrocyte size metabolic theory Varanidae

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The Cyclization of Alkyl Side Chains of Naphthalenes:The GC/Potential Energies/FTIR Approach

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American Journal of Analytical Chemistry 2014年第14期5卷 957-968页

作者： Pavel Straka Miroslava Novotná Petr Buryan olga Bicáková Institute of Rock Structure and Mechanics v.v.i.Academy of Sciences of the Czech RepublicPragueCzech Republic Institute of Chemical Technology PragueCzech Republic

Gas chromatographic measurements of the retention times of alkyl naphthalenes on packed columns with polar and non-polar stationary phases have proven that the logarithm of the relative retention time increases bi-linearly (not linearly) with the number of carbon atoms in a molecule. This is caused by a strong inclination of alkyl side chains toward intramolecular cyclization. A FTIR spectral analysis has shown that longer alkyl side chains of alkyl naphthalenes are cyclized through an interaction between the terminal CH3 group and the aromatic ring. Conventional aromatic-aliphatic molecules thus become new molecules with quasi-alicyclic rings. This, however, alters the effect of non-covalent van der Waals attractive forces both inside and outside the molecules, which is reflected in an exponential increase of the retention times of alkyl naphthalenes with a side chain longer than propyl and in the bi-linearity of the logarithmic dependence of the relative retention times on the number of carbons in the molecule.

关键词： Alkyl Naphtalenes Retention Times Molecular Mechanics van der Waals Forces

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