两种粒子计数器相结合测量大气气溶胶粒子折射率虚部

研究了两种粒子计数器,其中以光散射为原理的粒子计数器测量的是光学等效直径,测量结果受折射率的影响很大;以粒子飞行时间为原理的粒子计数器测量的是空气动力学直径,测量结果不受折射率的影响.利用两种仪器的同时测量结果来计算大气的折射率,并给出计算结果.     

ITO薄膜光电性能红外-可见光谱分析方法

研究了射频磁控溅射制备ITO薄膜,利用四探针方法、分光光度计测试薄膜面电阻及红外-可见光光谱,利用光谱特征研究了不同工艺对薄膜面电阻、载流子浓度、折射率等光电性能的影响.研究表明,随温度的升高ITO薄膜面电阻减小,载流子浓度增加,折射率减小,透过率增加;随氧分压的增加面电阻增大,载流子浓度减小.     

含氟丙烯酸酯光致聚合物的全息特性研究

提高记录单体在成膜物中的迁移速率,加大记录单体与成膜物的折射率差,可以实现光致聚合物的折射率空间调制最大化.本工作以高折射率的超支化聚酯(折射率1.586)为成膜树脂,利用超支化聚合物分子结构疏松、便于小分子在其间扩散的特性,同时以低折射率的单官能团含氟丙烯酸酯(折射率1.372)和高活性的双官能团丙烯酸酯(折射率1.457)为记录单体制备了光致聚合物全息膜,以衍射效率为指标优化单体构成和全息膜的厚度,研究了该全息膜的衍射效率、空间分辨率、折射率调制度等性能.该光致聚合物全息材料的折射率调制度为4.82×10-3,衍射效率达到99.4%,在空间分辨率3750 lp/mm的衍射效率仍然达到85.6%,感光灵敏度56 mJ/cm2.     

倾斜光纤光栅折射率传感特性研究

根据倾斜光纤光栅的折射率传感原理,通过仿真研究不同包层模式在不同包层直径条件下有效折射率和包层模谐振波长的变化规律。结果表明:随环境折射率的增大,各阶包层模式的有效折射率变大,高阶包层模具有更好的折射率灵敏度。包层直径越小,引起的有效折射率偏移量越大。最后给出了环境折射率1. 35～1. 40范围内的波长拟合关系。     

双散射角光学粒子计数器测量气溶胶折射率

本文提出了60°和90°双散射角OPC测量气溶胶折射率的新反演方法.利用60°和90°双散射角OPC样机进行了气溶胶折射率和粒子大小谱分布的实际测量.与滤膜取样积分片方法和Vaisala的能见度仪的测量结果对比表明,利用60°和90°双散射角OPC测量气溶胶折射率和谱分布结果是合理的,双散射角OPC方法是可行的.     

一维光折变光子晶格的带结构研究

利用双光束干涉在光折变LiNbO_3晶体中写入折射率周期性排列的光子晶格,运用平面波展开法研究这种光折变光子晶格的带结构,并对比不同折射率对比度下的带结构情况。     

一维光折变光子晶体正负折射率的实验实现

对利用光学方法在掺铁铌酸锂晶体中制作一维光折变光子晶体时的正负折射率进行了详细的理论分析和实验研究。当采用成像法制作一维光折变光子晶体时,通过控制成像掩模条纹的占空比,晶体中折射率降低的基础上出现了升高区域,即晶体内正、负折射率同时存在。实验结果显示,这种折射率分布与最佳占空比息息相关,并提高了一维光折变光子晶体折射率的对比度。     

磷掺杂对非晶硅薄膜结构及光电性能的影响

采用射频等离子增强化学气相沉积方法制备了磷掺杂氢化非晶硅(a-Si∶H)薄膜.通过Raman散射光谱研究了不同磷烷掺杂含量薄膜的微结构,利用分光光度计对薄膜的厚度、消光系数和折射率进行了模拟,用高阻仪测得了非晶硅薄膜暗电导率.结果表明:薄膜的中程有序度随着磷掺杂量φ(体积分数)的增加而减小;折射率在φ为0.8%时最大;...     

无色透锂长石的宝石学特征

利用常规仪器及大型珠宝检测仪器对两粒无色样品的宝石学及谱学特征进行分析研究,结果显示,样品密度约为2.33±0.01g/cm3,折射率在1.505～1.523之间,双折射率在0.015～0.017之间,放大观察可见明显的后刻面棱重影线,以及少量短柱状晶体包体,短波紫外光下呈中等紫红色荧光.化学成分分析表明样品Al、Si...     

光学玻璃进展（三）

碲酸盐玻璃的化学组成 以TeO2为主要组成的碲酸盐玻璃具有高折射率的特点.在光学方面的应用包括折射率2.0以上的高折射率玻璃和声光玻璃.50年以前,C.Stanworth研究了简单碲酸盐玻璃系统的性质,在二元BaO·5TeO2和PbO·5TeO2组成中获得折射率2.08和2.25的玻璃.TeO2本身不形成玻璃,加入其它氧化物以后,都能在很广的组成范围内形成玻璃.加入氧化物BaO、PbO、Bi2O3、Ta2O5、WO3等,可以提高折射率.图10总结了一些简单碲酸盐玻璃系统在nd-νd图中的位置.     

Effects of 445 nm, 520 nm,and 638 nm Laser Irradiation on the Dermal Cells

Background: The invention of non-ionizing emission devices revolutionized science, medicine, industry, and the military. Currently, different laser systems are commonly used, generating the potential threat of excessive radiation exposure, which can lead to adverse health effects. Skin is the organ most exposed to laser irradiation; therefore, this study aims to evaluate the effects of 445 nm, 520 nm, and 638 nm non-ionizing irradiation on keratinocytes and fibroblasts. Methods: Keratinocytes and fibroblasts were exposed to a different fluency of 445 nm, 520 nm, and 638 nm laser irradiation. In addition, viability, type of cell death, cell cycle distribution, and proliferation rates were investigated. Results: The 445 nm irradiation was cytotoxic to BJ-5ta (≥58.7 J/cm²) but not to Ker-CT cells. Exposure influenced the cell cycle distribution of Ker-CT (≥61.2 J/cm²) and BJ-5ta (≥27.6 J/cm²) cells, as well as the Bj-5ta proliferation rate (≥50.5 J/cm²). The 520 nm irradiation was cytotoxic to BJ-5ta (≥468.4 J/cm²) and Ker-CT (≥385.7 J/cm²) cells. Cell cycle distribution (≥27.6 J/cm²) of Ker-CT cells was also affected. The 638 nm irradiation was cytotoxic to BJ-5ta and Ker-CT cells (≥151.5 J/cm²). The proliferation rate and cell cycle distribution of BJ-5ta (≥192.9 J/cm²) and Ker-CT (13.8 and 41.3 J/cm²) cells were also affected. Conclusions: At high fluences, 455 nm, 520 nm, and 638 nm irradiation, representing blue, green, and red light spectra, are hazardous to keratinocytes and fibroblasts. However, laser irradiation may benefit the cells at low fluences by modulating the cell cycle and proliferation rate.     

Formation and applications of stable 10 nm to 500 nm supramolecular porphyrinic materials

Nanoscaled materials of organic dyes are of interest for a variety of potential applications because of the rich photonic properties that this class of molecules can impart. One mode to form such nanoscaled materials is via self-organization and self-assembly, using reasonably well understood methods in supramolecular chemistry. But there are inherent complexities that arise from the use of organic-based supramolecular materials, including stability toward dioxygen, structural stability, and nanoarchitectures that may change with environmental conditions. Porphyrinoids have rich photonic properties yet are remarkably stable, have a rigid core, are readily functionalized, and metalation of the macrocycle can impart a plethora of optical, electronic, and magnetic properties. While there are many <10 nm porphyrinic assemblies, which may or may not self-organize into crystals, there is a paucity of 10–500 nm porphyrinic materials that can be isolated and stored. A variety of strategies towards the latter nanoscopic porphyrinic materials are discussed in terms of design, construction, and nanoarchitecture. The hierarchical structures include colloids, nanorods, nanotubes, nanorings, and nano-crystalline materials. This prolegomenon emphasizes the supramolecular chemistry, structure-stability, and structure-function relationships. The goal herein is to examine general trends and delineate general principles.     

193nm光刻胶的研制

从主体树脂的结构设计、单体的合成工艺、主体树脂的合成工艺、光致产酸剂的评价、配方研究等多个方面论述了193nm光刻胶的研制工艺，合成出了多种适用的单体及多种结构的主体树脂，进行了大量的配方研究，筛选出了最佳配方．研制出的样品经美国SEMATECH实验室应用评价其最佳分辨率为0．1μm，最小曝光量为26mJ／cm^2，不但具有优异的分辨率和光敏性，而且还具有良好的粘附性和抗干法腐蚀性．     

532nm激光作用下RDX的解离

采用飞行时间质谱仪(TOFMS)研究了532nm激光作用下RDX的解离过程,得到RDX解离过程中的正、负离子飞行时间质谱图。根据离解产物离子的可能分布,提出了RDX的3种解离途径。结果表明,N-N和C-N键断裂竞争反应呈现在532nm激光作用下RDX的解离过程中。     

The Photodissociation of Pyridine at 193 nm

Using photofragmentation translational spectroscopy, the primary processes involved in the photodissociation of pyridine are investigated at 193 nm. Upon absorption of a single photon, HCN + C₄H₄, CH₃ + C,H₂N, C₃H₃ + C₂H₂N, and H + C₅H₄N are the observed primary pathways, with relative yields of 59%, 21%, 11%, and 9%, respectively. This paper reports the experimental details and results of this study. Comparison of the results of this study with a previous study in our laboratory investigating the photolysis of benzene serves as a direct measure of the strong influence substitution of a heteroatom in an aromatic ring can have on a molecule's photochemistry.     

Ozone Yields from Oxygen Irradiated at 193 nm

The use of ArF laser radiation at wavelength 193 nm to generate ozone from various pressures of oxygen gases was investigated. Kinetic results were interpreted from molecular spectroscopy and dynamics points of view. The 193 nm radiation can dissociate both oxygen molecules and ozone to produce oxygen atoms. This is an essential process in ozone generation. In this investigation, we focused on the mechanisms that ozone dissociates into three oxygen atoms or vibrationally excited oxygen molecules. The above mechanisms imply a potential process to improve the efficiency of ozone generation.     

Oscillations in catalytic reactions on the nm scale

We present Monte Carlo simulations of the oscillatory kinetics of CO oxidation on catalytic metals in the case when the reaction is accompanied by the formation of surface oxide. The lattice size is varied from 50 × 50 to 3 × 3 in order to mimic nm catalyst particles. More or less regular oscillations are found for the sizes down to 15 × 15. This revised version was published online in July 2006 with corrections to the Cover Date.     

Analysis of a SiGe MOSFET at 22nm

The present paper proposes a novel concept which can successfully reduce threshold voltage and increase switching speed of a conventional MOSFET. The proposed structures have been incorporated with a silicon germanium (SiGe) layer as a channel at the 22 nm technology node. Also, extensive analyses have been done to study the effects of replacing conventional polysilicon by graded dopent profile polysilicon, use of a high-k/silicon dioxide stack as a dielectric with graded dopent profile polysilicon and by using a high-k/silicon dioxide stack as a dielectric with a metal gate. Hafnium dioxide is used as a high-k material. Silvaco Athena and Atlas simulators are used for simulation as well as for finding electrical characteristics of the structures. For all the proposed structures two important parameters are studied in detail, threshold voltage and subthreshold slope. Comparing the three structures, it can be seen that using the high-k/silicon dioxide stack as a dielectric with a metal gate yields the best threshold voltage as well as good subthreshold slope which is directly related to the switching behaviour of the device. The required fabrication aspects of the modelled structures are also elaborated in detail.     

248nm光致抗蚀剂成膜树脂研究进展

光致抗蚀剂(photoresist)是制造超大规模集成电路的关键性材料之一,随着集成电路集成度的不断增加,光致抗蚀剂由g线(436nm)胶、i线(365nm)胶,逐渐发展到深紫外(DUV)(248nmKrF与193 nm ArF)胶。成膜树脂作为光致抗蚀剂的主要成分之一,决定了抗蚀剂的主要性能,因此研究成膜树脂具有重要的意义。本文综述了248 nm KrF光致抗蚀剂成膜树脂的研究进展,重点介绍了聚对羟基苯乙烯及其衍生物,并简要介绍了其合成方法及成像机理。     

Synthesis of spherical (30 nm) and rod-like (200 nm) zirconia co-reinforced mullite nanocomposites

The objective of this research is to study microstructure and phase evolution of zirconia–mullite (ZM) nanocomposites which were synthesized by the direct transformation from amorphous precursor monoliths. The monolithic precursors were heat treated at 950–1250 °C to obtain ZM composites. Scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) were employed to investigate the microstructure of the composites. A unique nano- and submicron-zirconia co-reinforced mullite composite microstructure was obtained after a controlled crystallization. The nano tetragonal zirconia (t-ZrO₂) grains (<50 nm) were spherical and embedded in the mullite lattice. The unconfined zirconia grains showed a preferred growth direction along 〈1 0 0〉 direction of t-ZrO₂, and formed submicron grains (<650 nm) with bar-like shape. The precursor derived ZM composites also demonstrated enhanced mechanical properties comparing with the conventional powder processed ZM composites.