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1.
In this study, flow cytometry was used for assessing and comparing the genome size (GS) and the whole genome base composition (AT/GC ratio) of the saw-toothed grain beetle Oryzaephilus surinamensis (L.). In addition, the presence and frequency of endosymbiotic Wolbachia bacteria was studied. The haploid GS was estimated to lie within the range of 151.5-154 Mbp in O. surinamensis, making it the smallest value of haploid GS known among beetles. Furthermore, it was found that in eight silo pest populations GS was significantly smaller than in eight feral (native) populations obtained from fallen oak acorns. The ability of O. surinamensis to colonize different habitats globally could be connected with an unusually AT-rich (for an invertebrate) genome (AT-base content ranging from 68 to 76%). Native (feral) populations of O. surinamensis appear to have genetically diverged from the storage-pest populations tested. Larvae of pest origin survived better than larvae of native (feral) origin under laboratory conditions, which resembled silo conditions more than natural habitats. 相似文献
2.
徐欣 《北京印刷学院学报》2008,16(3):73-74
近年来,三维(3D)动画技术日趋成熟,三维动画电影的出现极大地丰富了动画艺术的表现语言。角色设计是一部三维动画成功的基础,而我国对于三维动画角色的设计还没有形成系统的认识。三维动画角色较之二维动画角色的差异就是计算机三维技术的运用,因此,三维动画角色就出现了自己独特的设计原则和角色动态造型规律。技术特性决定着三维动画角色塑造成功与否。 相似文献
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4.
Corrosion properties of friction-stir processed cast NiAl bronze 总被引:1,自引:0,他引:1
Friction-stir processing (FSP) was adopted to modify the microstructure of a cast Cu-9Al-4.5Ni-4Fe NiAl bronze alloy (NAB). After FSP, the initial coarse microstructure of the cast NAB was transformed to a fine structure, and the porosity defects were eliminated. The microstructure modification changed the corrosion behavior of the NAB in a 3.5% NaCl solution. In a static immersion corrosion test, the FSP NAB exhibited significantly greater corrosion resistance compared to the cast counterpart. The polarization curve and electrochemical impedance spectroscopic (EIS) results indicated that the FSP NAB showed slightly lower electrochemical corrosion resistance. 相似文献
5.
人血清中结合甘胆酸含量测定,采用阻断法放射免疫分析药盒,达到直接测定血样中结合甘胆酸的含量。本药盒以~(125)I-甘胆酸组胺为标记抗原,放化纯>90%。用去激素正常人血清配制系列标准,标准浓度分别为0.25.100.250.1000.4000μg/dl。兔抗血清,16~#兔抗血清亲和常数K=2.6×10~8l/mol。以0.5%ANS(8-苯胺-1-萘磺酸)磷酸盐缓冲溶液为阻断剂。PEG(聚乙二醇)为分离沉淀剂。本药盒分析灵敏度10μg/dl。批内批间精密度分别为4.7%和12.5%。平均回收率109%。 相似文献
6.
陈述了一个基于单端共栅与共源共栅级联结构的超宽带低噪声放大器(LNA).该LNA用标准90-nm RFCMOS工艺实现并具有如下特征:在28.5~39 GHz频段内测得的平坦增益大于10 dB;-3 dB带宽从27~42 GHz达到了15 GHz,这几乎覆盖了整个Ka带;最小噪声系数(NF)为4.2dB,平均NF在27 ~ 42 GHz频段内为5.1 dB;S11在整个测试频段内小于-11 dB.40 GHz处输入三阶交调点(IIP3)的测试值为+2 dBm.整个电路的直流功耗为5.3 mW.包括焊盘在内的芯片面积为0.58 mm×0.48 mm. 相似文献
7.
C. Y. Lin Y. K. Fang S. F. Chen C. S. Lin T. H. Chou S. B. Hwang J. S. Hwang K. I. Lin 《Journal of Electronic Materials》2005,34(8):1123-1128
A comparative study of deposition nanocrystalline silicon (nc-Si) on various buffer layers is investigated. The nc-Si films
were deposited in a hot-wire chemical vapor deposition (CVD) system. Through Hall measurement, scanning electron microscopy
(SEM), atomic force microscope (AFM), Raman, and x-ray diffraction (XRD) analyses, it was found that the columnar grain (CG)
size, mobility, and volume fraction of crystalline-deposited nc-Si films increase with an increase of the buffer layers’ surface
roughness. The nc-Si film deposited on the nc-Si buffer layer possesses the highest Xc (volume fraction of crystalline) of
84.32%, Hall mobility of 45.9 (cm2/V s), and CG size of 200–220 nm, and it shows the strongest intensity of the XRD diffraction peak in (111). 相似文献
8.
主要从后期制作中如何正确获取CG素材的技术方面作了简单的分析和介绍,包括如何在三维软件、剪辑软件、合成软件之间高质量地传递素材,如何在后期制作中使用Flash动画素材,电视节目制作中图形、图像格式的使用,DVD素材在电视节目制作中的应用以及网络视频格式转换。 相似文献
9.
10.
MO Wen-hui School of Mechanical Science & Engineering Huazhong University of Science Technology Wuhan P.R.China 《国际设备工程与管理》2008,13(3)
When material properties, geometry parameters and applied loads are assumed to be stochastic, the vibration equation of a system is transformed to static problem by using Newmark method. In order to improve the computational efficiency and to save storage, the Conjugate Gradient (CG) method is presented. The CG is an effective method for solving a large system of linear equations and belongs to the method of iteration with rapid convergence and high precision. An example is given and calculated results are compared to validate the proposed methods. 相似文献