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排序方式: 共有1313条查询结果,搜索用时 879 毫秒
121.
Yuan Tianzhong Zeng Jinsong Wang Bin Cheng Zheng Chen Kefu 《Cellulose (London, England)》2021,28(12):7651-7662
Cellulose - This study aims to investigate the relationship between mechanical fibrillation, morphological properties, and rheological behavior of cellulosic fiber. Three types of cellulosic fibers... 相似文献
122.
123.
A semi-classical quantum theory of the cyclotron radiation of the nonrelativistic thermal electrons in a very strong magnetic
field is presented. The basic formulae of the absorption coefficient of cyclotron resonancek
vand the absorption (scattering) cross-section of cyclotron resonance σ
v
have been derived under the quadrupole approximation. σ
v
is an important quantity in the study of the “magnetic inverse-Compton scattering”. It is shown that σ
v
is greatly larger than the Thomson cross-sectron σT, which is important in discussing the magnetic inverse-Compton scattering of the relativistic electrons in a very strong
magnetic field.
Project supported by the National Natural Science Foundation of China and the Climbing Plan. 相似文献
124.
Yingchao Liu Jinsong Wu Sixiu Liu Dongxiao Zhuang Yongfei Wang Xuefei Shou Jianhong Zhu 《Colloids and surfaces. B, Biointerfaces》2009,71(2):187-193
Laser capture microdissection (LCM) technology combined with immunohistochemistry (immuno-LCM) is a valuable tool to obtain specific target cell populations and therefore this technique enables more accurate proteomic profile. In this study, we optimized the regular immuno-LCM technique to isolate and stain pure prolactin cells from either normal human pituitary (n = 6) or prolactioma (n = 11). Compared with the routine procedure, more intense and specific staining could be obtained when sections were pretreated with 0.2% Triton X-100 for 4 min. Interestingly, longer pretreatment (0.2% Triton X-100 for 10 min) or higher concentration (2% Triton X-100 for 4 and 10 min) greatly impaired labeling intensity and cell shape. Further scanning electron microscope study revealed that the component extracted from the cell surface by Triton X-100 was lipid. Using the optimized immuno-LCM technique, more pure prolactin cells could be isolated and prepared for further proteomic analysis. Taken together, we reported an optimized immuno-LCM technique that could effectively dissect pure target cells in different type pituitary adenomas for further proteomics analysis. 相似文献
125.
复合结构与流体耦合运动方程的时域分析方法 总被引:1,自引:0,他引:1
本文就复合结构与流体耦合的时域运动方程,利用核函数矩阵的特点,将二阶微分积分方程变形为Volterra型积分方程,然后引入积分变换,得到一组一阶常微分方程组,该微分方程组的形式与现代控制论中的状态方程类似。 相似文献
126.
该文指出了凸几何分析中几个具有较高应用价值的经典不等式之间的蕴涵关系. 相似文献
127.
降低聚氯乙烯膜黄连素选择性电极检出限的新方法 总被引:2,自引:0,他引:2
PVC药物选择性电极的检出限主要是由膜中活性物质的溶解和内参比溶液中被测离子在膜中的迁移所决定的。为了减少这两种不利因素的影响 ,采用内参比为含可乐定的氯化钠溶液的可乐定选择性电极测定黄连素。测定的线性范围为 1.0× 10 - 4~ 1.0× 10 - 8mol L ,平均斜率为 5 8.6mV decade ;检出下限为 2 .5×10 - 9mol L ,比已报道的检出下限要低 2~ 3个数量级。电极的选择性明显提高 ,选择性系数的测定更加可靠真实 ,并获得良好的重现性和稳定性。以标准加入法测定回收率 ,结果令人满意。 相似文献
128.
129.
正交共轭滤波器的构造 总被引:2,自引:0,他引:2
It is very importent for generating an orthonormal multiwavelet system to construct a conjugate quadrature filter(CQF). In this paper, a general method of deriving a length-L 1 conjugate quadrature filter from a length-L conjugate quadrature filter and vice versa is obtained. As a special case, we study generally the construction of any length-L 1 compactly supported symmetric-antisymmetric orthonormal multiwavelet system with multiplicity 2 from a length-L multiwavelet system and vice versa. Examples of conjugate quadrature filter are given. 相似文献
130.
The effects of gain narrowing and high order dispersions on the pulse duration in our kilohertz chirpedpulse amplification system have been compensated experimentally. Using an acousto-optic programmable dispersive filter (AOPDF), the spectral full-width at half-maximum (FWHM) is expanded from 30 to50 nm. Stable laser pulses with the duration of 30 fs (FWHM), which is 1.07 times Fourier-transformlimitation, have been acquired by pre-compensating the high order phase distortions using the phase measured by spectral phase interferometry for direct electric-field reconstruction (SPIDER). 相似文献