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《Journal of Natural History》2012,46(32):2987-2996
Glyphochaeta laudieni, a new genus and species of the “Spionidae”, is described from the Arctic. The specimens were collected from the Kongsfjorden, Spitsbergen, Svalbard, in a marine grotto. Glyphochaeta laudieni was associated with colonies of unidentified Bryozoa. This new genus and species is characterized by a prostomium with frontal horns, the absence of branchiae and sabre chaetae, and the presence of grooved spines which replace hooded hooks in some chaetigers of the middle body region. These spines are associated with glandular organs situated in neuropodia. The significance of characters for determining the systematic position of Glyphochaeta within “Spionidae” is discussed. Glyphochaeta laudieni is probably related to Pygospio elegans. 相似文献
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《Journal of Natural History》2012,46(45-46):2841-2854
A new genus and species of the family Parabathynellidae, Siambathynella laorsriae gen. nov. et sp. nov. is described from Thailand. The new genus displays an exclusive character: a distinctive male thoracopod VIII with a row of denticles on the basipod. The new species also displays a unique combination of morphological characters, including a seven-segmented antennule, seven-segmented antenna, sexual dimorphism on the antennule, exopod of thoracopod I one-segmented, exopod of thoracopod II–VII two-segmented, male thoracopod VIII lacking basipodal seta, female thoracopod VIII with two setae, lacking pleopods, sympod of the uropod with inhomonomous row of spines, and endopod of uropod with a spinous distal process and a large distal spine ornamented with rows of setules. This is the first record of Bathynellacea (family Parabathynellidae) in Thailand, extending the distributional range of this taxon in Asia. 相似文献
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贵州寒武系含有丰富的棘皮动物化石,其中凯里组及杷榔组中的始海百合数以千计.近期贵州下司淑里村杷榔组上部粉砂质泥岩中发现的新类型殷氏原始球状始海百合(新属、新种)Protogloboeocrinus yini (gen.et sp.nov.),使贵州寒武系棘皮动物分异度加大,达8属、种及1科、属、种未定,分属3个亚门.演化趋势是:类群增多,始海百合个体变小,缝孔变圆,吸盘附着的化石类型增多,生态日趋复杂.凯里生物群也是棘皮动物大辐射的窗口. 相似文献
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浙西北地区二叠系和三叠系的构造变形样式及其大地构造意义初步研究 总被引:1,自引:0,他引:1
浙西下三叠系统政棠组(T_1zh)发育有典型的鲍马序列,是一套深水相浊积岩建造;区域构造环境初步分析表明浙西北地区具被动大陆边缘沉积楔特征。下三叠系统政棠组(T_1zh)与二叠系协调变形,其构造变形样式总体上以向西北逆冲的冲褶席(duplex)~ 为特征,变形强度自南东向北西呈递减趋势。上三叠统乌灶组(T_3w)为含煤陆相磨拉石盆地建造,变形样式以宽缓褶皱和逆断层组合为主。该区大地构造相主要为前陆褶皱冲断带相,而土三叠统乌灶组(T_3w)为前陆磨拉石盆地相,二者对浙西北地区早中生代造山作用的研究具重要意义。 相似文献
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风能技术发展中的几个问题 总被引:6,自引:0,他引:6
贺德馨 《世界科技研究与发展》2003,25(4):44-48
改善能源结构,利用可再生能源,减轻环境污染,提高人民生活质量,已成了全球能源工业关注的一个热点,风能是目前最有开发利用前景和技术最成熟的一种新能源和可再生能源之一。随着风能开发和利用的发展,风能技术也取得了显著的进步,并逐渐成为能源技术中的一个分支。本文简要介绍当前风能技术发展中的几个关注的问题。 相似文献
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An early and primitive sauropod dinosaur, Gongxianosaurus shibeiensis (gen. et sp. nov.), from Lower Jurassic Dongyuemiao Member of Ziliujing Formation in Shibei Village, Gongxian County, Sichuan Province, China is described, which is among Gongxian dinosaur fossils discovered in 1997. Except for skull incomplete, fossils were well-preserved. It has concurrently some features of both sauropod and prosauropds. It is an intermediate type of evolution from prosauropod to sauropod, provides practical materials for studying of origin and evolution of sauropod dinosaur fauna, and a favourable way for stratigraphic correlation between Early Jurassic Ziliujing Formation and Lower Lufeng Formation, in the Sichuan Basin and the Central Yunnan Basin that lies to its southwest. 相似文献
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红树林目前还受到不可持续利用方式的严重威胁。为快速掌握广西北海市合浦县铁山港白沙镇榄根村近岸海域监测范围内红树林受损及其周边景观演变情况,采用无人机(UAV)技术和多时期高分辨率卫星影像,结合野外地面群落调查,利用目视解译方法,对榄根村近岸海域红树林及周边景观进行遥感监测与分析。结果显示,该区域红树林2017年12月、2018年10月、2019年6月、2020年4月受损面积分别为0.55,4.77,9.42,17.18 hm2,4年间红树林受损面积增长约30.23倍。将2020年4月红树林受损区按照受损程度不同分为死亡区和严重受损区,面积分别为7.81,9.37 hm2,斑块数分别为35,106个。研究期内榄根村红树林受损面积呈迅速增加趋势,主要位于潮沟两侧;死亡及严重退化区红树林群落形态上呈灰白色不规则斑块状;红树林受损斑块呈“多点开花”特点,有从斑块林缘向内部蔓延的趋势。遥感技术可有效提高红树林生态监测的工作效率和准确性,应用前景广阔。 相似文献
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WANG Sumin WU Lizhu ZHANG Liping TUNG Chenho 《科学通报(英文版)》2006,51(2):129-138
Supramolecular systems are broadly defined as multi-component molecular assemblies, in which the components are held together by a variety of weaker non-covalent interactions, such as hydrogen bonding, π-π stacking,and hydrophobic and lipophilic interac… 相似文献