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一种PMMA表面改性的热压键合方法研究 总被引:1,自引:0,他引:1
介绍了一种基于表面改性技术的PMMA热压键合新方法。PMMA表面首先用其单体MMA进行改性,然后在真空热压设备中热压键合。主要的键合参数如下:键合压力0.5MPa~2.5MPa,温度88℃~100℃,时间180s。通过拉力法测量了键合强度,其最大值可达到0.15MPa。实验结果表明,与常规的热压键合方法相比,该方法可有效地降低键合温度,减少键合时间,提高键合强度,从而可减少对PMMA基片上微细图形结构的破坏。使用聚合物的单体(MMA)对PMMA进行改性,可避免对微管道产生化学污染,有利于集成毛细管电泳的生化分析。利用品红和氢氧化钠混合溶液对键合后的微流体芯片进行密封性测试,结果表明,封装后的微流体芯片没有出现泄漏的情况。 相似文献
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烟幕激光和红外透过率对应关系研究 总被引:1,自引:2,他引:1
分析了烟幕激光透过率与红外透过率的对应关系,提出了利用相邻波段红外透过率推算同样光学路径激光透过率的多项式拟合方法,开展了实验研究.结果表明:特定波长的激光透过率与相应红外波段透过率利用二项式拟合,其透过率计算误差在3%以内. 相似文献
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研究雾中红外辐射衰减特性,有助于提高武器装备雾天条件下的红外对抗能力。基于大气辐射传输软件(CART)、Beer-Lambert定律、Mie散射理论和雾滴谱分布函数,计算雾滴粒子群红外辐射透过率,对红外辐射在平流雾和辐射雾中的传输衰减特性进行研究。以近红外辐射1. 064μm、中红外辐射3. 8μm和远红外辐射10. 6μm在轻雾条件下为例,结合3个地区实测数据,分析了能见度、传输距离、入射光波长和晴朗大气透过率计算值对平流雾和辐射雾总透过率的影响。结果显示在轻雾条件下,辐射雾衰减小于平流雾衰减,远红外辐射10. 6μm具有很好的传输性能,地区气象参数不同对其有显著影响。 相似文献
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大口径的地基红外望远镜必须安装在具有良好大气条件的观测台站才能充分发挥其性能,天空背景辐射和大气传输特性是地基红外望远镜站址选择所需考虑的重要内容。采用消光-小角度散射法在西藏羊八井实测了太阳直接红外辐射和大气背景红外辐射,并根据备选站点的大气参数,采用CART软件计算了当地8~14 m波段整层垂直大气的光谱透过率、太阳直接光谱辐射和地面大气垂直向下的背景光谱辐射,以及相关量的波段积分值,这些结果有助于地基红外太阳望远镜的站址选择。 相似文献
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ZnS薄膜生长温度对ZnS/PS体系结构和发光的影响 总被引:1,自引:0,他引:1
用电化学阳极氧化法制备了一定孔隙率的多孔硅(PS,Porous Silicon)样品,然后以PS为衬底用脉冲激光沉积(PLD)的方法在100℃、200℃和300℃下生长ZnS薄膜.X射线衍射(XRD)结果表明,样品都在28.5°附近有一个较强的衍射峰,对应于β-ZnS(111)晶向,说明薄膜沿该方向择优取向生长,但由于衬底PS粗糙的表面结构,衍射峰的半高全宽(FWHM)较大.随着ZnS薄膜生长温度的升高,薄膜的衍射峰强度逐渐增强.扫描电子显微镜(SEM)像显示,随着薄膜生长温度的升高,构成薄膜的纳米晶粒生长变大.室温下的光致发光(PL)谱表明,随着薄膜生长温度的升高,ZnS的发光强度增强而PS的发光强度减弱,把ZnS的蓝绿光与PS的红光叠加,在可见光区450~700 nm形成了一个较宽的光致发光谱带,呈现较强的白光发射. 相似文献
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C.S. Pathak D.D. Mishra V. Agarwala M.K. Mandal 《Materials Science in Semiconductor Processing》2013,16(2):525-529
In this work, we synthesized zinc sulfide (ZnS) nanoparticles by the mechanochemical route using zinc acetate and sodium sulfide as source materials in a high energy planetary ball mill at rotation speed of 300 rpm with ball to powder ratio 5:1 for 30–120 min. Powder samples were collected at duration of 30 min for different analyses. The milled powders were washed with methanol to remove impurity and dried at 50 °C for 2 h. ZnS nanoparticles are characterized by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, UV–vis–NIR spectrophotometry and fluorescence spectrophotometry. The crystallite size of synthesized ZnS nanoparticles is found to be approximately 2 nm. The optical band gap of the ZnS nanoparticles is found to be in the range of 4.71–5.17 eV. Room temperature photoluminescence (PL) spectra of the samples exhibit blue-light emission using UV excitation wavelength of 280 nm. 相似文献
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用脉冲激光沉积法(PLD)在多孔硅(PS)衬底上生长ZnS薄膜,分别在300℃、400℃和500℃下真空退火。用X射线衍射(XRD)和扫描电子显微镜(SEM)研究了退火对ZnS薄膜的晶体结构和表面形貌的影响,并测量了ZnS/PS复合体系的光致发光(PL)谱和异质结的I-V特性曲线。研究表明,ZnS薄膜仅在28.5°附近存在着(111)方向的高度取向生长,由此判断薄膜是单晶立方结构的-βZnS。随着退火温度的升高,-βZnS的(111)衍射峰强度逐渐增大,且ZnS薄膜表面变得更加均匀致密,说明高温退火可以有效地促进晶粒的结合并改善结晶质量。ZnS/PS复合体系的PL谱中,随着退火温度升高,ZnS薄膜的自激活发光强度增大,而PS的发光强度减小,说明退火处理更有利于ZnS薄膜的发光。根据三基色叠加的原理,ZnS的蓝、绿光与PS的红光相叠加,ZnS/PS体系可以发射出较强的白光。但过高的退火温度会影响整个ZnS/PS体系的白光发射。ZnS/PS异质结的I-V特性曲线呈现出整流特性,且随着退火温度的升高其正向电流增加。 相似文献
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Thin films of ZnS were deposited on soda lime glass substrates by a modified close-space sublimation technique. The change
in optical and structural properties of the films deposited at various substrate temperatures (150–450°C) was investigated.
X-ray diffraction spectra showed that films were polycrystalline in nature having cubic structure oriented only along (111)
plan. The crystallinity of films increased with the substrate temperature up to 250°C. However, crystallinity decreased with
further increase of substrate temperature and films became amorphous at 450°C. The atomic force microscopy data revealed that
the films become more uniform and dense with the increase of substrate temperature. Optical properties of the films were determined
from the transmittance data using Swanepoel model. It was observed that the energy band gap is increased from 3.52 to 3.65
eV and refractive index of the films are decreased with the increase of substrate temperature. Moreover, considerable improvement
in blue response of the films was noticed with increasing substrate temperature. 相似文献
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Indium doped ZnS (ZnS:In) films were prepared on glass substrate using thermal evaporation technol- ogy. It was found that the structural, optical and electrical properties of ZnS:ln films strongly depend on the substrate temperature (Ts). By X-ray diffraction (XRD), atomic force microscopy (AFM), transmittance spectroscopy, and electric performance measurements, the effect of Ts on ZnS:In film is studied in detail. It reveals that Ts has impor- tant effect on ZnS grain size, crystallinity, lattice disorder, etc., which further leads to the obvious influence on its optical and electrical performance. Under the optimized Ts, the performance, especially the conductivity, achieved in this work is far higher than that reported for other n-type ZnS films. 相似文献
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采用传统陶瓷方法制作了Mg1+xAl0.8Cr0.6Fe0.6Lay(x=–0.10,–0.05,0,0.05,0.10,0.15,0.20;y=0,0.05)系高温NTC陶瓷材料,借用XRD、SEM和电性能测试等手段,研究了MgO含量及La2O3掺杂对陶瓷材料相结构和电学性能的影响规律。结果表明:适当增加MgO的含量可以有效提高陶瓷材料的常温电阻率和B值(材料常数),La2O3掺杂可改善高温NTC陶瓷材料B值的稳定性。当x=0.15,y=0.05时,在1 873 K烧结可获得ρ25=7.55×1010.cm,B=8 795 K的高温NTC陶瓷材料。 相似文献
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The temperature and frequency dependences of the permittivity of polycrystalline zinc sulfide are investigated. The permittivity is calculated from the electronic-structure parameters. It is shown that an increase in the permittivity at frequencies below 10 kHz occurs as a result of space-charge polarization, which is due to the presence of charged dislocations in interlayer and grain boundaries. 相似文献