37 resultados para Pez, Hieronymus, 1685-1762.

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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介绍了微电子和微电子机械系统(MEMS)中几种常用的变形和形貌测量方法以及相关的测量设备。其中相移云纹干涉技术用于微电子器件的面内位移测量,灵敏度可达到纳米量级。显微栅线投影技术用于MEMS的离面变形和形貌测量,灵敏度可达0.1微米。

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The formation of the non-uniformity of the non-volatile volume grating in doubly doped LiNbO3 crystals is studied in detail. We find that the non-uniformity of the grating is mainly caused by strong ultraviolet light absorption, and the average saturation space-charge field is small and the diffraction efficiency is low as a result of the non-uniformity of the grating. In order to optimize the uniformity of the grating, we propose the recording scheme by using two sensitizing beams simultaneously from the two opposite sides of the crystals. Theoretical simulations and experimental verifications are performed. Results show that the well uniformed grating with high diffraction efficiency can be obtained by using this optimization scheme. (c) 2004 Elsevier B.V. All rights reserved.

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本文回顾了龙胆科蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和翼萼蔓属的研究历史,对这些类群的外部形态、花部解剖结构、染色体、花粉形态及胚胎学进行了研究,并结合已有的资料,探讨了这些类群的分类学问题。主要结论如下: 1.外部形态 蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和龙胆属其他组之 间以及蔓龙胆属和翼萼蔓属之间在外部形态上均存在差异。 2.花部解剖结构 蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和龙胆属其他组的花部解剖结构存在较多地相似之处,同时蔓龙胆属和双蝴蝶属的花被维管束和腺体比龙胆属狭蕊组和龙胆属其他组的特化。而翼萼蔓属的花部解剖结构与蔓龙胆属的差异较大,与扁蕾属的花部解剖结构较相似。 3.染色体 本文对蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和翼萼蔓属的7种植物的染色体数目、基数和核型对称性作了研究,其中6种植物的染色体为首次报道,它们是:披针叶蔓龙胆C.delavayi、双蝴蝶T.chnense、峨眉双蝴蝶T.cordatum、锯齿龙胆 G.serra、毛脉龙胆G.souliei、和翼萼蔓P.volubilis。蔓龙胆属、双蝴蝶属和龙胆属狭蕊组的核型不对称性稍强于龙胆属其他组,但在染色体组成上十分相似。翼萼蔓属和蔓龙胆属的染色体差异较大,面与扁蕾属的染色体较相似。 4.花粉形态蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和龙胆属其他组均具有球形或长球形、3孔沟、沟长而宽、外壁纹饰为条纹一无穿孔和条纹一穿孔的花粉类型。而翼萼蔓属的花粉为球形、纹饰为网状纹馋与蔓龙胆属不同,与扁蕾属的花粉较相似。 5.胚胎学 本文对披针叶蔓龙胆C,delavayi、双蝴蝶T.chinense、峨眉双蝴蝶T.cordatum、条纹龙胆G. striata和翼萼蔓P.volubilis作了较详细的胚胎学研究,这些类群在花药壁的分化和形成、胚珠和胎座类型、卵器中的助细胞和反足细胞、种皮以及胚发育等特征上存在差异,并且在胚胎学特征上各自拥有原始和进化的性状。蔓龙胆属、双蝴蝶属和龙胆属之间的胚胎学性状差异较大,龙胆属狭蕊组与双蝴蝶属的胚胎学性状较相似,而与蔓龙胆属和龙胆属其他组的差吴较大。翼萼蔓属的胚胎学性状与扁蕾属的较相似,而与蔓龙胆属的差异较大。 6.综合分析外部形态、花部解剖结构、染色体、花粉形态及胚胎学性状,结果表明,蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和龙胆属其他组是亲缘关系十分相近的类群,在某些特征上已存在明显地演化极向,但在大多数特征上演化极向不明。蔓龙胆属和双蝴蝶属分别作为独立属处理较为合适,而且两属的亲缘关系很近。狭蕊组仍应放在龙胆属,蔓龙胆属比双蝴蝶属与龙胆属的亲缘关系更近一些。翼萼蔓属也应作为一独立属处理,而且该属可能与扁蕾属的亲缘关系较近,而与蔓龙胆属亲缘关系较远。 7.本文还讨论了蔓龙胆属、双蝴蝶属、龙胆属狭蕊组和翼萼蔓属的地理分布。

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Three cDNA sequences coding for elapid cathelicidins were cloned from constructed venom gland cDNA libraries of Naja atra, Bungarus fasciatus and Ophiophagus hannah. The open reading frames of the cloned elapid cathelicidins were all composed of 576 bp an

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目的应用基因芯片研究大鼠肝缺血预处理后残存肝组织再生过程中基因表达谱的动态变化。方法 Sprague-dawley(SD)大鼠肝在缺血再灌注前行缺血预处理(10min缺血后10min再灌注),再灌注期间行70%肝叶切除建立余肝再生模型,用affmetrix RAT GeneArray 1.0ST基因表达谱芯片筛选大鼠再生肝组织中差异表达基因进行功能分析及归类。结果再生肝组织有差异表达基因1103条,涉及代谢相关基因、细胞周期调控基因、炎症反应相关基因、凋亡相关基因、信号传导相关基因、细胞因子相关基因、生长因子基因等,差异表达基因显著性的表达趋势有7种。结论缺血预处理后肝再生的过程是多基因调控的动态变化过程,用基因芯片有助于研究肝再生的机制,为促进肝再生提供治疗的潜在靶点。

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Eleven polymorphic microsatellite loci were characterized for the endangered conifer Taxus yunnanensis. Eight loci were isolated through SSR-anchored PCR, one locus was developed by cross-species amplification tests, while the last two loci were obtained

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由通式(Ⅰ)所示的N-取代基-4-取代苯基-5-烷基-5-取代苄基吡咯烷酮-2类化合物,具有钙拮抗活性,可应用于制备治疗脑功能障碍病药物,早老性痴呆病药物,增强学习记忆药物。其中R1是氢,取代苯甲酰基,1—5个碳原子的链状酰基。R2是氢,1—10个碳原子的正、异构烷基。X是氢,邻、间、对位取代的氟、氯、溴原子或甲氧基、乙氧基。吡咯烷酮-2环上的4,5-二或三取代包括顺式(RS及SR)构型、反式(SS)及RR构型。合成通式(Ⅰ)及其吡咯烷酮-2的方法。通式(Ⅰ)如上。

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以武汉东湖柱状沉积物为研究对象,利用磷脂法测定了3个采样点各层的微生物量,同时测定了沉积物中各层的pH,简要分析了沉积物中磷脂含量的垂向分布与pH垂向分布的相关性。结果表明:各样点沉积物中磷脂平均含量分别为:1号点59.40nmol/g.dw,2号点为20.56nmol/g.dw,3号点为31.57nmol/g.dw。在沉积物的垂向分布上,微生物量与pH均随着沉积物深度的增加而降低,并且存在很高的相关系数。

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采用顶空固相微萃取-气相色谱/质谱联用测定了水中常见的3种异味化合物,即2-甲基异茨醇、土腥素和β-柠檬醛。研究并讨论了纤维头的类型、盐的种类和浓度、温度、萃取时间、搅拌和解吸时间等因素对异味化合物萃取量的影响。结果表明:在水样中加入30%(W/V)的NaCl溶液,采用65μmPDMS/DVB纤维头,在搅拌的条件下,于60℃顶空萃取40min为异味化合物固相微萃取的最佳条件。在优化的条件下,使异味化合物吸附于纤维涂层后,将其在250℃高温下解吸,再用GC-MS分析。土腥素、β-柠檬醛、2-甲基异茨醇的检出

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The tandem organic light-emitting diodes (OLEDs) with an effective charge-generation connection structure of Mg-doped tris(8-hydroxyquinoline) aluminum (Alq(3))/Molybdenum oxide (MoO3)-doped 3, 4, 9, 10-perylenetetracarboxylic dianhydride (PTCDA) were presented. At a current density of 50 mA/cm(2), the current efficiency of the tandem OLED with two standard NPB/Alq(3) emitting units is 4.2 cd/A, which is 1.7 times greater than that of the single EL device. The tandem OLED with the similar connection structure of Mg-doped PTCDA/MoO3-doped PTCDA was also fabricated and the influences of the different connection units on the current efficiency of the tandem OLED were discussed as well.

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