双环戊二烯苯酚树脂的合成新工艺

以双环戊二烯（DCPD）和苯酚为原料,甲磺酸为催化剂,合成了双环戊二烯苯酚树脂。适宜工艺条件:苯酚与DCPD摩尔比为5、反应温度120 ℃、反应时间5 h、催化剂质量分数为1.5%,收率89%。所得的双环戊二烯苯酚树脂（DPR）经催化加氢法在H2气压力1.5 MPa、催化剂Pd/Al2O3用量为原料质量分数的0.5%、反应温度80 ℃条件下对树脂进行脱色处理。 得到浅黄色双环戊二烯苯酚树脂,收率89%,经IR和1H NMR表征分析其为目的产物,产物指标达到国际同类产品的质量标准。     

Dynamic thermal modeling and parameter identification for a monolithic laser diode module

We improved the thermal equivalent-circuit model of the laser diode module(LDM) to evaluate its thermal dynamic properties and calculate the junction temperature of the laser diode with a high accuracy.The thermal parameters and the transient junction temperature of the LDM are modeled and obtained according to the temperature of the thermistor integrated in the module.Our improved thermal model is verified indirectly by monitoring the emission wavelength of the laser diode against gas absorption lines,and several thermal parameters are obtained with the temperature uncertainty of 0.01 K in the thermal dynamic process.     

An efficient Jacobian scaling method for time-domain optical mammography

<正>Time-domain diffuse optical tomography can efficiently reconstruct optical parameters which can be further applied in diagnosing early breast cancer.Nevertheless,the performances of reconstructed imaging are badly influenced by different Jacobian magnitudes of absorption coefficient and reduced scattering coefficient.With the introudction of a relative data type based on generalized pulse spectrum technique, an efficient Jacobian scaling method is proposed.The interrelated simulated validation is also revealed for the enhancing performances.     

一种基于多级小波域分解的时域扩散光学层析成像方法的研究

面向基于有限差分光扩散模型的平板乳腺扩散光学层析反演问题,提出了一种有效提高图像重建质量的方法.与基于全空间域离散像点的传统重建算法不同,本方法采用小波函数对吸收系数和散射系数在空间域进行多尺度分解,在减少低分辨率重建中光学参量的个数、有效改善重建过程病态性的同时,通过逐级细化分解尺度,最终提高了图像的量化度和空间分辨率.数值模拟表明,该方法可实现目标体边对边4 mm的空间分辨率,量化度明显高于传统算法.     

基于图像分割的时域乳腺扩散光学层析成像方法

鉴于乳腺光学层析成像方法中的不适定性严重影响重建图像性能,引入图像分割技术.通过选择合适的图像分割阈值,将基于全域重建的图像分割为背景区域和目标区域,再对得到的“目标区域”进行二次图像重建.数值模拟研究表明,该技术可有效地减小反演变量的维数,提高重建图像的性能.     

Dynamic thermal modeling and parameter identification for monolithic laser diode module

We improve the thermal equivalent-circuit model of the laser diode module (LDM) to evaluate its thermal dynamic property and calculate the junction temperature of the laser diode with a high accuracy. The thermal parameters and the transient junction temperature of LDM are modeled and obtained according to the temperature of the thermistor integrated in the module. Our improved thermal model is verified indirectly by monitoring the emission wavelength of the laser diode against gas absorption lines, and several thermal parameters are obtained with the temperature uncertainty of 0.01 K in the thermal dynamic process.     

基于图像分割的时域乳腺扩散光学层析成像方法

鉴于乳腺光学层析成像方法中的不适定性严重影响重建图像性能,引入图像分割技术.通过选择合适的图像分割阈值,将基于全域重建的图像分割为背景区域和目标区域,再对得到的"目标区域"进行二次图像重建.数值模拟研究表明,该技术可有效地减小反演变量的维数,提高重建图像的性能.     

一种基于测量空间样条插值扩展的扩散光学层析图像改善方法

面向基于光扩散模型的平板乳腺扩散光学层析反演问题,提出了一种有效提高图像重建质量的方法.针对扩散光学成像逆问题存在不适定性的特点,在不增加源和探测器数量的基础上,通过样条插值的方法有效地扩展测量空间,由此改善了逆问题中未知量远远多于已知量(测量值)的问题,在一定程度上减轻了反演问题的不适定性,使得重建图像在空间分辨率和量化度上都有相应的提高.通过对内置两非光学均匀立方体的平板模型进行模拟成像,并分析重建图像的空间对比度.结果表明:经过样条插值对测量空间的扩展,重建目标的空间分辨率可以达到边对边4 mm.