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71.
《Journal of Natural History》2012,46(21-22):1447-1475
72.
73.
《Journal of Natural History》2012,46(3-4):133-183
The variation in ovipositor sculpture and additional features of the ovipositor apparatus in Tenthredinoidea is explored. Two outgroups and 85 species of tenthredinoids were examined, the emphasis of the taxon sampling being on Nematinae. Twenty-four morphological characters where scored and the data set was analysed under different weighting conditions. The topologies derived from analysing the character set in TNT are poorly resolved and highly unstable when analytical settings are changed. Only a few clades, the Tenthredinoidea s. str., the Diprionidae, the Cimbicidae and the Argidae + Pergidae are consistently retrieved. The functional implications of the variation in ovipositor morphology within Tenthredinidae is discussed in relation to the qualities of the host plant, e.g. the hardness and the depth of penetration in plant tissue. 相似文献
74.
《Journal of Natural History》2012,46(9):1259-1290
Monocotyle is revised and three new species are proposed. Monocotyle corali sp. nov. is described from the gills of the cowtail ray, Pastinachus sephen (Forsskål) (Dasyatididae), and is distinguished from other members of Monocotyle by the large hamuli with a distinct tail on the guard and by the male copulatory organ with three loops and a wing-like accessory piece at the distal end. Monocotyle jordani sp. nov. from the gills of the southern eagle ray, Myliobatis australis Macleay (Myliobatididae), is differentiated by the male copulatory organ with a large, unique accessory piece. Monocotyle youngi sp. nov., from the gills of Himantura fai Jordan and Seale (Dasyatididae), has marginal haptoral papillae armed with 12 to 15 sclerites, a male copulatory organ with 20 loops and a unique accessory piece at the distal end. Monocotyle trygoni (Venkatanarsaiah and Kulkarni, 1980) Timofeeva, 1985 is synonymized with M. spirophallus Tripathi, 1959 and M. spirophallus is redescribed fully. There are now 16 valid species of Monocotyle and a key to species is presented. Additional data and illustrations of important taxonomic characters are provided. The developmental sequence of the male copulatory organ of M. spiremae Measures, Beverley-Burton and Williams, 1990 from juvenile to adult is described. The anterior glands and the type of secretion they contain are also documented for several species of Monocotyle. 相似文献
75.
《Journal of Natural History》2012,46(16):2001-2011
The morphology and infraciliature of two marine synhymeniid ciliates, Orthodonella apohamatus nov. spec. and Orthodonella gutta (Cohn, 1866) Kahl, 1931, collected from coastal water off Qingdao, China, were studied on living cells and using protargol silver impregnation. The diagnosis for O. apohamatus nov. spec.: marine Orthodonella with length×width about 60–160×20–35?µm in vivo; lanceolate body shape with conspicuous beak-like projection at anterior end; 42–60 (mean 53) somatic kineties, including 28–42 on ventral and 13–20 on dorsal side; synhymenium with about 54–62 dikinetids; pharyngeal basket composed of 8–13 rods; four contractile vacuoles, two in middle near left margin and two at posterior end of cell; one elongated macronucleus and one micronucleus. Based on a Qingdao population, an improved diagnosis for the poorly known species, O. gutta is suggested: marine Orthodonella in vivo about 140–200×60–100?µm; body widely ellipsoidal with contractile beak-like anterior end; 62–74 (mean 66) somatic kineties with ca 41–48 ventral and 20–26 dorsal; synhymenium consisting of 43–70 dikinetids; 11–14 pharyngeal rods; one to several contractile vacuoles distributed in caudal area of cell; numerous cortical granules tiny and colourless; one ovoid macronucleus. 相似文献
76.
利用自制多功能微弧氧化膜的制备系统对TC4钛合金进行表面处理, 通过扫描电镜(SEM)和X射线衍射仪(XRD)研究脉冲频率(f)对氧化膜生长特性、 表面形貌和相组成的影响. 结果表明, 当f≤2 000 Hz时, 成膜速率随f增加迅速减小; 当2 000 Hz<f<4 000 Hz时, 成膜速率随f增加而减小的趋势变缓; 当f≥4 000 Hz时, 成膜速率不随f发生变化. 该氧化膜表面多孔, 随f的增加, 膜表面微孔尺寸逐渐减少, 微孔密度逐渐增加. 膜层主要由锐钛矿和金红石相TiO2及少量不饱和氧化物TiO2-x(0.02<x<0.07)相组成, 其中锐钛矿和金红石相TiO2的相对含量随f的变化不明显, 而TiO2-x的相对含量当f≤2 000 Hz时较高, 当f>2 000 Hz时, TiO2-x的相含量明显减少. 相似文献
77.
6005A铝合金大截面复杂制品作为轨道车体的边梁或枕梁,对轨道车体的整体起连接和承重作用,是动车组车体的关键部位。采用电子万能试验机、铝型材压力试验机、光学显微镜等研究了速度达400 km·h-1动车组车体底边梁用6005A铝型材的强度、显微组织和断口形貌等,旨在为动车组用铝挤压型材产品检验和工艺制度制定提供技术支持与指导。 相似文献
78.
【目的】观察海黍子不同分枝的形态特征,并研究离体培养条件下三生分枝的生长和生殖托数量的变化情况。【方法】采用形态观察法和离体培养技术,分别研究三生分枝在次生分枝上的分布、其数量与次生分枝长度的关系、其长度与生殖托数量的关系,并对离体培养前后三生分枝特定生长率及生殖托数量变化情况进行研究。【结果】三生分枝数量与次生分枝长度呈正相关;生殖托数量同三生分枝的长度呈正相关。离体培养实验期内,生殖托数量增长一般不超过2个;三生分枝均有不同程度的增长,特定生长率多数集中在0%~2%。【结论】海黍子不同分枝尤其是三生分枝的生长和发育有助于海黍子有性繁殖过程,可以保障海黍子群体的不断繁衍。 相似文献
79.
80.
采用XRF,SEM,XRD,IR,NMR等测试手段对苏州高岭土及其在550~850℃的煅烧产物进行了研究.实验结果表明:煅烧后产物由煅烧前的晶态转变成了非晶态;煅烧温度对高岭土煅烧产物形貌和结构有一定影响,温度越高,产物中棒状,块状小颗粒越少,Al的四配位量越多. 相似文献