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81.
针对惯性约束聚变(ICF)激光等离子体诊断系统应用的需求,提出一种采用非线性相位拟合法设计单透镜代替理想对数轴锥镜的方法。对所要得到的球面透镜与理想对数轴锥镜的相位进行拟合,求解得出所需要的球面透镜参量。设计了用于激光等离子体诊断系统的长焦深透镜,并对透镜的焦深、轴向光场均匀性、横向均匀性、焦斑旁瓣等指标进行分析。数值分析结果表明,长焦深透镜具有与理想对数轴锥镜相同的相位分布,焦深、轴向光场均匀性、横向均匀性、焦斑旁瓣均符合设计要求,验证了非线性相位拟合法的正确性。 相似文献
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Steady motions of the Van der Pol oscillator and an oscillator with hysteresis are studied numerically in this paper. Some
features of periodic, almost periodic and chaotic motions of forced self-sustained oscillators are investigated.
This paper has been presented at the ICTAM XVI Lyngby. 相似文献
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羧甲基壳聚糖含有丰富的羧基和氨基, 通过1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐(EDC)和N-羟基琥珀酰亚胺(NHS)共催化交联羧甲基壳聚糖形成新型水凝胶. 调节EDC/NHS用量, 制备不同交联度的羧甲基壳聚糖水凝胶(CMCS hydrogels). 研究水凝胶的流变行为, 结果表明, 高交联度的水凝胶具有较好的弹性形变能力, 较高的储存模量, 这是因为随着交联度的升高, 羧甲基壳聚糖水凝胶化学交联网络结构趋于完善. 以胸腺五肽(TP-5)为模型药物, 初步评价CMCS水凝胶药物释放行为, 结果表明水凝胶交联度越高, 胸腺五肽释放速度越慢. MTT法初步评价了水凝胶细胞毒性, 细胞形态和细胞相对增值速率, 结果表明水凝胶毒性很低. 由此可见, 水凝胶具有良好的生物相容性, 在药物缓释和组织工程领域具有广阔的应用前景. 相似文献
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Dr. Ze Yang Weiwei Cui Dr. Kun Wang Yuwei Song Dr. Fuhua Zhao Dr. Ning Wang Prof. Yunze Long Prof. Huanlei Wang Prof. Changshui Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(22):5643-5647
Here, a new approach to further improve graphdiyne (GDY) based materials by using benzyl disulfide (BDS) as the sulfur source is demonstrated. The S radicals, generated from the homolysis of BDS, can react with the acetylenic bonds and be well confined in the triangle-like pores of GDY, forming S-GDY. The as-prepared S-GDY, which possesses numerous heteroatom defects and active sites, is suitable for applications in many electronic devices, such as lithium ion batteries (LIBs). As expected, the assembled LIBs based on S-GDY displayed improved electrochemical properties, including larger capacity and superior rate capability. 相似文献
89.
准确测量激光远场光斑强度时空分布是分析强激光大气传输效应和评价激光系统性能的有效手段。概述了测量激光光斑强度分布的几种方法及其适用性,重点叙述了基于阵列探测法的强激光远场光斑强度分布测量技术,总结分析了量热阵列法、光电阵列法和量热/光电复合法等三类阵列探测系统应用特点。最后介绍了两种分别用于测量连续波高能激光和重频脉冲激光的光电阵列靶斑仪,系统具有结构紧凑的特点,能够满足运动靶目标上强激光参数测量要求。 相似文献
90.
Microbubbles containing gadolinium as contrast agents for both phase contrast and magnetic resonance imaging 下载免费PDF全文
Rongbiao Tang Fuhua Yan Guo-Yuan Yang Ke-Min Chen 《Journal of synchrotron radiation》2018,25(2):560-564
Portal vein imaging is an important method for investigating portal venous disorders. However, the diagnostic requirements are not usually satisfied when using single imaging techniques. Diagnostic accuracy can be improved by combining different imaging techniques. Contrast agents that can be used for combined imaging modalities are needed. In this study, the feasibility of using microbubbles containing gadolinium (MCG) as contrast agents for both phase contrast imaging (PCI) and magnetic resonance imaging (MRI) are investigated. MCG were made by encapsulating sulfur hexafluoride (SF6) gas with gadolinium and lyophilized powder. Absorption contrast imaging (ACI) and PCI of MCG were performed and compared in vitro. MCG were injected into the main portal trunk of living rats. PCI and MRI were performed at 2 min and 10 min after MCG injection, respectively. PCI exploited the differences in the refractive index and visibly showed the MCG, which were not detectable by ACI. PCI could facilitate clear revelation of the MCG‐infused portal veins. The diameter of the portal veins could be determined by the largest MCG in the same portal vein. The minimum diameter of clearly detected portal veins was about 300 µm by MRI. These results indicate that MCG could enhance both PCI and MRI for imaging portal veins. The detection sensitivity of PCI and MRI could compensate for each other when using MCG contrast agents for animals. 相似文献