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101.
Most of lasers used for imaging and heating gold nanorods are single-wavelength lasers and their efficiency to interact with different gold nanorods is limited. In this study, we demonstrated that supercontinuum light could be a fast, effective and energy efficient excitation source for heating of gold nanorods. The photothermal effect and the heating speed of gold nanorods illuminated by a supercontinuum light and femtosecond pulses through two-photon excitation are experimentally studied through using transmission electron microscopy images and photoluminescence images of gold nanorods. It is found that the supercontinuum light improves the heating speed by 39 %, and melts 30 % more of gold nanorods compared with the femtosecond pulse excitation approach. The heating speed of gold nanorods by supercontinuum light depends not only on its polarization states, but also on the pulse width and numerical aperture of its focused beam. It has been found that the supercontinuum is more efficient in heating of gold nanorods, making it potentially valuable for clinical applications. 相似文献
102.
J.L. Liu Y. Lu Y. Shi S.L. Gu R.L. Jiang F. Wang Y.D. Zheng 《Applied Physics A: Materials Science & Processing》1998,66(5):539-541
2 at 750 °C and 850 °C. The oxide and interface morphology are characterized by cross-sectional scanning electron microscope
images. It is found that the oxidized nanowire following oxidation at 750 °C still keeps its pentagon shape even if it has
been oxidized for 19 h. However, the oxidized samples at 850 °C become circular in shape. The oxidation-temperature dependence
of the sample shapes is discussed. Our results should be useful in generating silicon nanowires coated with SiO2 in microelectronic technology with careful selection of the SiO2 growth temperatures.
Received: 26 September 1997/Accepted: 8 December 1997 相似文献
103.
Targeted damage effects of high intensity focused ultrasound (HIFU) on liver tissues of Guizhou Province miniswine 总被引:12,自引:0,他引:12
Wang ZB Wu F Wang ZL Zhang Z Zou JZ Liu C Liu YG Cheng G Du YH He ZC Gu ML Wang ZG Feng R 《Ultrasonics sonochemistry》1997,4(2):181-182
HIFU can pass through tissues and accurately damage target tissues inside organisms. This article reports on the oriented damage effects of HIFU upon miniswine internal and external liver tissues, and suggests a new conception of the 'biological focal field'. The results revealed that: (1) HIFU can be used to damage accurately liver tissues under the guide of a B-modal ultrasound device; (2) the scope of the injury is connected with sound intensity and irradiation time; and (3) the different layers of tissue through which the ultrasound has passed remain undamaged. 相似文献
104.
In this paper, we study the semilocal convergence for a fifth-order method for solving nonlinear equations in Banach spaces.
The semilocal convergence of this method is established by using recurrence relations. We prove an existence-uniqueness theorem
and give a priori error bounds which demonstrates the R-order of the method. As compared with the Jarratt method in Hernández
and Salanova (Southwest J Pure Appl Math 1:29–40, 1999) and the Multi-super-Halley method in Wang et al. (Numer Algorithms 56:497–516, 2011), the differentiability conditions of the convergence of the method in this paper are mild and the R-order is improved. Finally,
we give some numerical applications to demonstrate our approach. 相似文献
105.
文章研究了一类函数增量的局部渐近性质,发现这类函数增量的局部渐近性对于一元实函数,二元及多元实函数,向量值函数和复函数在一定条件下都会保持不变,进而提出了两个相关的猜想:此类函数增量的渐近性是关于函数变换的拓扑不变量。 相似文献
106.
稀土元素原子发射光谱及其谱线干扰的高分辨率ICP—AES研究… 总被引:1,自引:1,他引:1
稀土元素在当今生产、生活中具有极重要的地位,由于稀土元素的原子发射光谱极为复杂,因此光谱干扰给稀土元素的原子发射光谱分析带来极大的困难。本工作利用高分辨率ICP-AES仪器详细研究了Sm基体对其他稀土元素分析线的光谱干扰,获得了大量的光谱及光谱干扰信息,为以稀土为基体的痕量稀土分析线的选择及光谱分析提供了依据。 相似文献
107.
We present a simple scheme of atom localization in a subwavelength domain via manipulation of probe absorption spectrum in a four-level atomic system. Due to the joint quantum interference induced by the standing-wave and radio-frequency driving fields, the localization peak position and number as well as the conditional position probability can be controlled by properly adjusting the system parameters. The proposed scheme may provide a promising way to achieve high-precision and high-resolution 1D atom localization. 相似文献
108.
针对拼接干涉测量技术除了引入拼接误差,还将引入机械运动误差的问题,为此提出一种X射线反射镜的非零位干涉测量方法,无需拼接便可实现零回程误差的高精度干涉测量。利用一块高精度平面镜来标定干涉系统在全视场范围内的回程误差。通过将待测非球面镜划分成多个子孔径,每个子孔径可近似看作一个平面,这样可以从标定数据库中找到该子孔径所对应的回程误差,通过简单的矩阵拼接可得到整个待测非球面镜的回程误差。以X射线椭圆柱面反射镜为例进行实验,实现X射线椭圆柱面反射镜非零位干涉测量面形的回程误差有效标定,相比于拼接干涉测量方法二者结果一致性较好,证实所提方法的正确性。 相似文献
109.
Song Zi-Long Zhu Yun Liu Jing-Rui Guo Shu-Ke Gu Yu-Cheng Han Xinya Dong Hong-Qiang Sun Qi Zhang Wei-Hua Zhang Ming-Zhi 《Molecular diversity》2021,25(1):205-221
Molecular Diversity - Based on the strategy of diversity-oriented synthesis and the structures of natural product pimprinine and streptochlorin, two series of novel pimprinine derivatives... 相似文献
110.