45 resultados para Verseghy, Ferenc, 1757-1822.

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Most morphological characters diagnostic of the 13 Chinese species of the cyprinid genus Sinilabeo Rendahl, 1932, are identical to those of the genus Bangana Hamilton, 1822. Consequently, these 13 species are transferred to Bangana. A revised diagnosis is provided for the now-expanded genus Bangana, and a dichotomous key and taxonomic and nomenclatural notes are included for the following valid Chinese species: B. decora, B. dero, B. devdevi, B. discognathoides, B. lemassoni, B. lippa, B. rendahli, B. tonkinensis, B. tungting, B. wui, B. xanthogenys, B. yunnanensis, and B. zhui. Literature reports, by Chinese authors, of Sinilabeo dero from the upper Irrawady River basin, in Yunnan, are based on misidentifcations of B. devdevi. Sinilabeo cirrhinoides Wu and Lin in Wu, Lin, Chen, Chen and He, 1977, and S. laticeps Wu and Lin in Wu, Lin, Chen, Chen and He, 1977, are junior subjective synonyms of B. devdevi and B. lippa, respectively. Sinilabeo yunnanensis Wu, Lin, Chen, Chen and He, 1977, is an available name, and a lectotype is designated for the species. Bangana zhui ( Zheng and Chen, 1983) is a valid species distinct from B. yunnanensis.

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首先对气动塞式喷管内外流干扰的机理进行了分析,在此基础上对外流干扰对气动塞式喷管性能的影响进行了数值模拟研究。数值方法采用NND格式求解二维N-S方程,对于不同的背压和来流马赫数条件进行了大量的数值实验。通过计算揭示了不同外流条件下气动塞式喷管的流动特征以及外流干扰对喷管性能的影响规律。

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The paper proposes Latin hypercube sampling combined with the stratified sampling of variance reduction technique to calculate accurate fracture probability. In the compound sampling, the number of simulations is relatively small and the calculation error is satisfactory.

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The middle reach of the Yangtze River, customarily called the Jingjiang River, together with its diversion channels and Dongting Lake, form a large complicated drainage system. In the last five decades, significant geomorphological changes have occurred in the drainage system, including the shrinkage of diversion channels, contraction of Dongting Lake, changes in the rating curve at the Luoshan station, and cutoffs of the lower Jingjiang River. These changes are believed to be the cause of the occurrence of abnormal floods in the Jingjiang River. Qualitative analyses suggest that the first three factors aggravate the flood situation in the lower Jingjiang River, while the last factor seems beneficial for flood prevention. To quantitatively evaluate these conclusions, a finite-volume numerical model was constructed. A series of numerical simulations were carried out to test the individual and combined effects of the aforementioned four factors, and these simulations showed that high flood stages in the Jingjiang River clearly are related to the geomorphological changes.

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The control role of the relative phase between the probe and driving fields on gain, dispersion and populations in an open V-type three-level system with spontaneously generated coherence is studied. The result shows that by adjusting the value of the relative phase, the transformation between lasing with inversion and lasing without inversion (LWI) can be realized and high dispersion (refractive index) without absorption can be obtained. The shape and value range of the dispersion curve are similar to those of the gain curve, and this similarity is closely related to the relative phase. The effects of the atomic exit and injection rates and the incoherent pump rate on the control role of the relative phase are also analysed. It is found easier to get LWI by adjusting the value of the relative phase using the open system rather than the closed system, and using an incoherent pump rather than without using the incoherent pump. Moreover the open system can give a larger LWI gain than the closed system.

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We explore the use of the Radon-Wigner transform, which is associated with the fractional Fourier transform of the pupil function, for determining the point spread function (PSF) of an incoherant defocused optical system. Then we introduce these phase-space tools to analyse the wavefront coding imaging system. It is shown that the shape of the PSF for such a system is highly invarient to the defocous-related aberrations except for a lateral shift. The optical transfer function of this system is also investigated briefly from a new understanding of ambiguity function.

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ZnO crystals with dimensions of 30 x 38 x 8 turn 3 have been grown by the hydrothermal method using a mixed solution of KOH, LiOH and H2O2. The growing rates for +c(0001) and -c(000 (1) over bar) were 0.17 and 0.09 mm/day, respectively. The crystal color was very light green for +c sector and dark brown for -c sector. For the +c sector, the resistivity at room temperature was 80 0 cm, the carrier concentration was about 10(4)/cm(3), and the mobility was about 100 cm(2)/Vs. The full-width at half-maximum (FWHM) of double axis X-ray rocking curve for the polished Zn face cut from +c sector was 45 arcsec. The photoluminescence (PL) spectrum and the absorption spectrum of +c part of the crystals at room temperature were also reported and discussed in this paper. (c) 2008 Elsevier B.V. All rights reserved.

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We investigate mechanisms of laser induced damage thresholds (LIDTs) of multi-layer dielectric gratings (AIDG,). It is found that the laser damage thresholds of MDGs and unstructured dielectric multi-layer coatings (the substrate of MDG) are 3.15J/cm(2) and 9.32 J/cm(2), respectively, at 1064nm (12ns) with the Littrow angle 51.2 degrees and the TEM00 mode. The laser-induced damage mechanism of multi-layer dielectric is presented with the analysis of the following factors: The dominant factor is the pollution on the corrugated surface, which is induced by the complex manufacture process of multi-layer dielectric gratings; another is the electric field distribution along the corrugated surface. The third reason is due to the reduction in stoichiometry of oxide films, resulting from the manufacture process of etching.

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  毛冠菊属是菊科21个“有问题”属中的一个,主要分布于青藏高原地区。按照林镕、陈艺林的概念,它包含了Nannoglottis、.Stereosanthus、Vierhapperia、Senecio和Doronicum5个属的成员。它曾先后被放入旋覆花族、千里光族和紫菀族,在上述三族中的亚族位置也不确定。它的许多重要性状,如舌片颜色、染色体数目等等,人们所知甚少。由于缺乏野外工作以及看不到大多数名字的模式,林镕、陈艺林对该属的修订有待深入的研究。本文研究了该属的外部形态学、微形态学、解剖学、孢粉学、细胞学、生态学以及ITS序列,确定了毛冠菊属的分类位置,并建立了一个新的属下分类系统。 1.外部形态 在检查大量标本(包括大多数模式)和野外居群考察的基础上,分析了主要外部形态学性状的变异式样及其对划定物种范围的价值。共确认以下9个种:青海毛冠菊、厚毛毛冠菊、狭舌毛冠菊、虎克毛冠菊、宽苞毛冠菊、大果毛冠菊、毛冠菊、玉龙毛冠菊和云南毛冠菊。川西毛冠菊被处理成狭舌毛冠菊的异名。 2.微形态学 在光镜下检查了毛冠菊属9种和紫菀族2个代表属的花柱的形状、花药顶端不育附属物、花药基部、花药基部、花盘、花丝领、药室内壁细胞等微形态性状。除了花柱基外,其他的微形态学在属内一致。管状花的花柱形态支持将毛冠菊属放在紫菀族,但其药室内壁细胞两极加厚式样表明它和广义的旋覆花有某些联系。 3.叶表皮研究 在光镜和电镜下检查了毛冠菊属8个种的叶表皮特征。.所有种的气孔器都为不规则型。青海毛冠菊表皮细胞的为多边形,而其他种都为不规则型。青海毛冠菊表皮角质层的加厚方式也与其他种明显不同。 4.扫描电镜下的舌片和花柱分枝特征 在扫描电镜下观察毛冠菊属8种和紫菀族7个代表种的舌片近轴面表皮细胞。发现毛冠菊属的舌片近轴面表皮细胞都为板状,并且沿细胞中央特征性加厚,这与紫菀族类型的表皮细胞一致,但毛冠菊属表皮细胞的角质层主要是纵向条纹或皱纹,而紫菀族总是横向的条纹或皱纹,明显不同。 在扫描电镜下又检查了毛冠菊属8种和紫菀族8个代表种的管状花花柱分枝近轴面的结构,结果在毛冠菊属管状花花柱分枝的近轴面都发现了柱头毛状的突起,而在紫菀族8种中没有发现。从突起的形状和位置判断,它可能是残存的、未充分发育的柱头毛。这表明雌性不育管状花可能刚刚从两性管状花演化而来。 也在扫描电镜下观察了毛冠菊属6种和紫菀族8个代表种的舌状花和丝状花的花柱分枝的远轴面,结果在毛冠菊属4种中发现了类似扫集毛状的突起。从这种突起的位置和形状判断,它可能是残余的扫集毛。这种突起在除雏菊以外的其他紫菀族代表种中缺失。 5.细胞学 检查了毛冠菊属8种的细胞学性状。结果发现毛冠菊属所有种的染色体基数都为x -9。染色体长度大约4um-lOum。核型公式:毛冠菊、厚毛毛冠菊、狭舌毛冠菊、宽苞毛冠菊和云南毛冠菊都为2n=14m+2sm+2st;玉龙毛冠菊、大果毛冠菊和青海毛冠菊都为2n=12m+4sm+2st。A1、A2值在属内没有明显差异。所有种的核型都是2A型。这表明在物种形成的过程中没有多倍化参与,毛冠菊属宜放在紫菀族而不是千里光族。细胞学证据支持毛冠菊属为一单系类群。 6.分子生物学 测定了毛冠菊属7种的ITS序列,并从基因库里下载了46个ITS序列,涵盖紫菀族14个亚属和旋覆花族、春黄菊族、金盏菊族。以旋覆花族、春黄菊族、金盏菊族为外类群。简约性分析显示,毛冠菊属在紫菀族中,并有较高的bootstrap值,在紫菀族中处于基部位置。Olearia和Chiliotrichum两个Hinterhuberinae亚族的代表属与毛冠菊属密切相关。在属下系统发育分析中,Olearia和Chiliotrichum被选做外类群。652个性状中,共有7】个信息位点(31个在ITSI,33个在ITS2,7个在5.8S)。简约性分析时只获得一棵最简约树。树上有两个明显的进化支,一支仅有青海毛冠菊一种,另一支包含其他种类。这种分支方式也得到形态学和生态学证据的支持。 7.毛冠菊属的系统学 从上述结果可以看出,毛冠菊属宜放入紫菀族中,在紫菀族中处于基部位置,与Hinterhuberinae亚族关系密切。综合上述研究结果,提出一个新的属下 分类系统: 毛冠菊属的新系统 组I单头组Sect. Monocephala T.G.Gao et YL.Chen Sect nov. 青海毛冠菊Nannoglottis ravida (C.Winkl.)Y.L.Chen 组II毛冠菊组Sect. Nannoglottis 系1.长舌系Ser. Delavayanae Ling et YL.Chen 厚毛毛冠菊Nannoglottis delavayi(Franch.)Ling et Y.L.Chen 狭舌毛冠菊Nannoglottis gynura(C.Winkl.) Ling et YL.Chen 虎克毛冠菊Nannoglottis hookeri (C.B.Clarke ex Hook.f.)Kitam. 宽苞毛冠菊Nannoglottis latisquama Ling et Y.L.Chen 大果毛冠菊Nannoglottis macrocarpa Ling et YL.Chen 系2.短舌系Ser. Nannoglottis 毛冠菊Nannoglottis carpesioides Maxim. 玉龙毛冠菊Nannoglottis hieraciphylla (Hand.-Mzt.)Ling et YL.Chen 云南毛冠菊Nannoglottis yuennanensis (Hand.-Mzt.) Hand.-Mzt.

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本发明涉及一种血管收缩因子及其制备方法和在制药中的应用,属于生物医学领域。该血管收缩因子是从中国两栖类动物大蹼铃蟾皮肤中分离得到的分子量为65KDa由3条肽链组成的蛋白质,包括2条相同的轻链和1条重链,轻链的分子量为16KDa,重链的分子量为33KDa,等电点6.2,糖含量17-19%。血管收缩因子轻链的N-端20个氨基酸序列结构是:Phe Ser Asp Leu Gln IleGly Ser Leu Lys Cys Ala Val Ala Ala Tyr Asp Gln Gly Ala;重链的N-端封闭。其制备方法是收集大蹼铃蟾皮肤匀浆液或者皮肤分泌物,离心去除沉淀、收集上清液冷冻干燥,经离子交换,凝胶过滤纯化即可得到。该血管收缩因子具有强烈收缩血管,诱导血小板聚集的活性,可作为制备心血管疾病治疗药物和诊断试剂的应用。

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A new species of the subfamily Barbinae, Tor yingjiangensis, is recognized from Yunnan province, China. It can be distinguished from other Tor species by the following combination of characters: last simple dorsal-fin ray osseous and non-serrated; no forward directed predorsal procumbent spine; head length considerably longer than body depth; no tubercles on the snout or sides of the face; 18-20 gill rakers on the outside of first gill arch; 24-26 lateral line scales; median lobe of lower lip short, its posterior margin truncate, not extending to the vertical across the inner corners of the mouth; and the condition of the lower lip consistent in individuals of different sizes. The new species has been misidentified previously as Tor putitora (Hamilton, F. 1822. An account of the fishes found in the River Ganges and its Branches. Edinburgh & London. 405 pp), which occurs in the Ganges and Indus River basins. The new species can easily be distinguished from T. putitora by having 3-3.5 (vs. 2.5) scales from lateral line to pelvic-fin origin, shorter caudal peduncle length (13.0% vs. 17.2% of standard length), lesser body depth (26.4% vs. 24.0% of standard length) and longer caudal peduncle depth (12.0% vs. 10.9% of standard length), no longitudinal stripe present along side of body, and eyes visible in ventral view of head.

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温度为15℃时,添加20,40,80和100μg/mL维生素B12后,萼花臂尾轮虫(Brachionuscalyciflorus)种群密度随时间增加而增长,其回归方程依次为:y=e(0.1757+0.2974x),y=4.6765x1.2079,y=7.7798x1.0175和y=e(0.6117+0.3469x),密度显著高于对照组(t=4.56,8.15,8.53和9.86;P<0.01)。对照组和添加组最大混交雌体百分率依次为57.69,76.09,73.81,60.00和45.15%,最大卵雌比依

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结合武汉市湖泊特点及分析湖泊污染带来的危害 ,叙述了一种以引江灌湖为主的生态恢复技术———物理生态工程 ,它包括 :引江灌湖模式 ;光合耗营养盐系统 ;鱼类除营养盐、抑藻系统 ;底栖、浮游动物控营养盐系统和面源截营养盐系统。并从理论及过去他人的研究实例中阐述其可行性

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untius是典型的热带和亚热带鱼类类群,主要生活在山涧溪流及敞水环境。Hamilton(1822)建立此分类单元时将它作为Cyprinus属的一个亚属。Bleeker(1863)用PuntiusHamilton属名代替SystomusMc′Clelland,确立...