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101.
用数字干涉仪测量变形镜影响函数的实验研究 总被引:6,自引:0,他引:6
分析了变形反射镜面形影响函数的意义,鉴于自适应光学系统中波前探测大都以测量波前斜率为基础的特点,提出应研究斜率影响函数,并在此基础上构成波前复原矩阵。还介绍了用数字干涉仪测量变形镜影响函数的方法和结果,并对测量结果进行了分析,得到了影响函数的各种参数,例如:交连值,高斯指数,特征宽度等。并将干涉法测量斜率影响函数的结果与实际的哈特探测器的测试结果进行了比较。 相似文献
102.
光学非球面面形拟合方法研究 总被引:3,自引:0,他引:3
作者在研制一台高精度检测非球面仪器的过程中,探讨了二次和高次非球面面形方程参数的拟合方法。计算实例表明,线性化拟合法和非线性拟合法较圆满地达到了各种非球面面形拟合精度和实时处理的要求。 相似文献
103.
Sonochemical and sonophotocatalytic degradation of malachite green: the effect of carbon tetrachloride on reaction rates 总被引:3,自引:0,他引:3
A comparative study between the sonolytic, photocatalytic and sonophotocatalytic oxidation processes of aqueous solutions of malachite green was carried out in the presence of carbon tetrachloride, under a low power ultrasonic field (<15 W) and using titanium dioxide as a photocatalyst. The effect of a number of parameters such as ultrasonic intensity, TiO2 crystalline structure and the presence of CCl4 were studied using an inexpensive reactor. Enhanced rates of sonolytic degradation of malachite green in the presence of CCl4 were demonstrated. On the other hand, the simultaneous use of sonolysis and photocatalysis in the presence of CCl4 does not improve the degradation rate of malachite green in comparison with the one obtained using only sonolysis, but it makes possible a faster oxidative degradation of some reaction intermediaries. Finally, in air saturated solutions both processes, the sonolytic and the photocatalytic one, follow a first-order rate law. 相似文献
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To investigate the effect of photodynamic therapy (PDT) with hematoporphrin monomethyl ether (HMME) on bovine immunodeficiency virus (BIV) can provide the basis theory for photoinactivation of human immunodeficiency virus (HIV). To assess the protection of HMME-PDT on the cell line Cf2Th infected with BIVR29 by 3-(4,5)-dimethylthiahiazol-2-yl-3,5-di-phenytetrazolium bromide (MTT) with power density of 5 and 25 mW/cm2 and energy density from 0.6 to 3 J/cm<'2>. To observe the inhibition of membrane fusion using a new reporter cell line BIVE by fluorescence microscope. HMME-PDT has significant protectant effects on Cf2Th-BIVR29 with both power densities, especially in the group of high power density. Fluorescent microscope shows that there is no significant difference between the group of PDT and control, which means PDT could not inhibit the BIV-mediated membrane fusion. 相似文献
107.
Proton magnetic resonance spectroscopy (1H MRS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) provide functional information, including vascular volume, vascular permeability and choline (Cho) metabolism. In this study, we applied these two imaging modalities to quantitatively characterize 36 malignant breast lesions in 32 patients and analyzed the correlation between them. Cho concentration was quantified by single-voxel 1H MRS using water as an internal reference. The measured Cho levels ranged from 0.32 to 10.47 mmol/kg, consistent with previously reported values. In 25 mass-type lesions, the Cho concentration was significantly correlated with tumor size (r=.69, P<.0002). In addition, the Cho level was found to be significantly higher in lesions presenting as mass-type lesions compared to non-mass-type diffuse enhancements (P=.035). The enhancement kinetics from tissues covered within each MRS voxel were measured and analyzed with a two-compartmental model to obtain pharmacokinetic parameters Ktrans and kep. A significant correlation was found between the Cho level and the pharmacokinetic parameter kep (r=.62, P<.0001), indicating that tissues with a high Cho level have higher wash-out rates in DCE MRI. The results suggest a correlation between Cho metabolism and angiogenesis activity, which might be explained by the association of Cho with cell replication and angiogenesis required to support tumor growth. 相似文献
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A special form of electrodynamical response to a gravitational wave:outgoing and imploding photon fluxes 下载免费PDF全文
We have investigated the interaction of an electromagnetic (EM) wave with a standing gravitational wave (GW) in an external static magnetic field,and obtained concrete forms of first-order perturbative EM energy fluxes.Unlike the propagating properties of the “left-circular” and “right-circular” waves of the tangential perturbative energy fluxes around the symmetrical axis,the radial perturbative energy fluxes are expressed as the outgoing and imploding waves to the symmetrical axis.We also examine several physical examples and show that this effect can produce very small but nonvanishing radial perturbative photon fluxes.This may be useful for EM detection of the high-frequency relic GWs of the GHz region in quintessential inflationary models. 相似文献