环氧丙烯酸酯低聚物制备过程若干影响因素

在不同阻聚剂用量、投料比、投料方式等条件下合成环氧丙烯酸酯.对合成产物进行了红外光谱分析.制备了紫外光固化涂料,测定了固化膜的凝胶质量分数.结果表明,阻聚剂用量增加有利于提高酯化反应程度及固化膜凝胶质量分数,但当阻聚剂用量达到1.0%(质量分数)时酯化程度降低、固化膜凝胶质量分数降低.反应物中环氧树脂稍过量有利于提高酯化反应程度;当n(Er)∶n(AA)为1∶2.0时固化膜凝胶质量分数最高.将丙烯酸与催化剂、阻聚剂预先混合后再加入到环氧树脂中的投料方式有利于提高合成产物的酯化程度.     

Little-known and phylogenetically obscure South African estuarine microgastropods (Mollusca: Truncatelloidea) as living animals

Areas of the Knysna estuarine bay in the Western Cape are dominated by three endemic South African truncatelloid microgastropods, temporarily known as ‘Hydrobia’ knysnaensis (Krauss), ‘Assiminea’ capensis (Sowerby) and ‘Assiminea’ globulus Connolly. Although first described 80–170 years ago and present in abundance (up to 100,000 m^?2), they remain surrounded by confusion and still await taxonomic assignment, largely because they appear most atypical members of their groups by virtue of anatomy and/or biogeography and/or habitat. This study contributes in-life perspectives to morphological and phylogenetic analyses known to be on-going. At Knysna, they are syntopic: at least two occurring in >85% and all three in >40% of individual 0.0026 m² samples from their region of dominance. Nevertheless, they tend to greater abundance in divergent microhabitats; ‘A.’ globulus dominating higher tidal levels, and ‘A.’ capensis and ‘Hydrobia’ lower ones; the former especially unvegetated sediment, the latter, if anything, seagrass. Interspecific feeding interactions appear unlikely to be responsible for these patterns, other evidence suggesting that all are maintained below carrying capacity. Field biology of ‘H.’ knysnaensis generally appears equivalent to that of northern-hemisphere intertidal hydrobiids and that of ‘A.’ globulus is typically assimineid, albeit at atypically low shore height. Unlike assimineids, however, ‘A.’ capensis is truly aquatic. The success of these truncatelloids in unusual circumstances may be consequent on the absence from South Africa of other microgastropod groups that fill their niches elsewhere in the southern hemisphere.     

How Stomaphis aphids use their giant proboscides

To penetrate tree bark, arboreal aphids of the genus Stomaphis Walk. (Hemiptera: Aphididae: Lachninae) have proboscides up to three times their body length. Our observations of S. quercus (L.) complement a recent analysis of the anatomy and function of these mouthparts by clarifying how these relatively short-legged aphids move their proboscides between the resting position, pointing back, and the prognathous working position. The absence of crumenae in Stomaphis aphids and their feeding technique are discussed.     

Morphology of thalassinidean (Crustacea: Decapoda) mouthparts and pereiopods in relation to feeding,ecology and grooming

The morphology of the mouthparts and pereiopods of three thalassinidean mudshrimps, Callianassa subterranea (Montagu), Jaxea nocturna Nardo and Upogebia stellata (Montagu) (Decapoda: Thalassinidea) are described. The distribution of setae is also described and related to function, in particular to feeding and grooming. The comparative morphology of the maxillipeds and pereiopods showed greatest differences between species and can be related to differences in feeding behaviour. Callianassa subterranea has mouthpart morphology and setation suitable for handling sediment particles and highly specialized pereiopods consistent with the digging activity of a deposit feeder. Upogebia stellata is the most densely setose of the three species and many of the appendages bear layered fringes of setae which are used to trap fine particles during suspension feeding. Jaxea nocturna appears to possess mouthpart and pereiopod setal combinations suitable for a fine sediment diet but is the least morphologically specialized species. It does not use its pereiopods in grooming behaviour. Specialized denticulate setae on the coxa of the third maxilliped may take over the gill grooming functions performed by the pereiopods of C. subterranea and U. stellata. In C. subterranea and U. stellata the feeding structures are adapted to a specific trophic mode but have features that allow other modes to be used, whilst J. nocturna is much less specialized and may represent a more primitive thalassinidean form.     

Taxonomy of the arboreal polychaete Lycastopsis catarractarum Feuerborn (Namanereidinae: Nereididae), with a discussion of the feeding biology of the species

Lycastopsis catarractarum Feuerborn, 1931 is redescribed and a neotype designated. A full synonymy is given and all known records of the species are examined. Gut contents are analysed for two populations (Papua New Guinea and Fiji) and the feeding biology and ecology are discussed.     

STATISTICAL ANALYSIS OF YARN APPEARANCE IN SINGLE PLATED WORK KNITTED ON LARGE DIAMETER CIRCULAR WEFT KNITTING MACHINE

In this paper the significance analysis has been made of the factors influencing the yarn appearing of single plated weft-knit fabrics knitted on large diameter machine by a mathematical statistical method. By means of orthogonal test and variance analysis, it is known that the feeding tension is the significant factor influencing the yarn appearance and the ground yarn tension should be larger than the face yarn tension. Through comparison, it is also known that the drawing off force should be regulated suitably, the carrier should be near the first closed needle, and the sinker should be out late slightly.     

胶济沿线产业带空间结构演化模式研究（下）

探讨了胶济沿线产业带在１９４９至１９９０年间的空间演化模式及其过程，将空间结构的演变划分为两个阶段：一是单一强大的区域中心与强大的次级中心同构成一个完整的多核心空间系统；二是强大的全国中心，二个区域中心和一系列小地方中心沿胶济发展轴出现，这些中心共同构成点轴空间系统，由此可得出：增长并非同时出现在每个地方，并通过不同渠道的扩散对空间经济产生终极影响。     

17层煤沿空留巷技术应用

本文通过对17层煤沿空留巷技术和沿空送巷技术的对比,凸显了沿空留巷技术的先进性及经济的可行性,为其它不稳定顶板条件下沿空留巷技术应用提供了一种有益尝试。     

旋转体体积公式及其推论

传统的旋转体体积求法是通过对坐标的积分求得，借助数学和物理的方法推导出一个脱离坐标系的旋转体体积公式，利用这个公式，用悬线法测出均匀转面的重心，就可求出旋转体体积，并在生活和生产中得到广泛的应用．     

三元数解析

本文详列三元数运算公式，引进三元数的特征概念，给出三元数运算另一等价形式，讨论了三元数运算的几何意义，并应用三元数运算推导出一般三次代数方程的求根公式。