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1.
本文提出了设计高斯场光学膜系的方法、电子枪真空反应溅射工艺和反射率实时监控技术.利用所提出的设计方法、工艺和监控技术,在面积为0.2×2μm~2的半导体激光器(LD)芯片有源层解理面上,设计制备了剩余反射率低至5×10~(-4)的减反膜,从而获得性能优越的行波半导体激光放大器.  相似文献   

2.
合成了1-[3-(N一吡咯)丙基]-3-己基咪唑四氟硼酸盐离子液体,以其为单体,采用电位阶跃法制备出聚 离子液体膜修饰玻碳电极,经十二烷基磺酸根阴离子交换,获得聚离子液体膜疏水界面.研究了厚朴酚在该聚离 子液体膜疏水界面上的电化学行为,采用用微分脉冲伏安法实现了厚朴酚的电化学测定.在优化条件下,厚朴酚的 氧化峰峰电流与其浓度在1.0×10-8~5.0×10-6 mol/L和5.0×10-6~2.0×10-5 mol/L范围内呈良好的线性关 系,检测限为7.1×10-9 mol/L(S/N=3).该方法成功用于中药厚朴中厚朴酚测定.  相似文献   

3.
微分电位溶出法测柠檬酸   总被引:3,自引:0,他引:3  
报道了微分电位溶出法 (DPS)在 0 .1mol/LHAc -NaAc介质中测定柠檬酸 .在选定条件下 ,于4 .0× 10 - 5~ 8.0× 10 - 3mol/L范围内有较好的线性关系 ,r =0 .9893,检测限为 1.0× 10 - 5mol/L .用于常见汽水测定 ,结果满意  相似文献   

4.
尼古丁分子印迹聚邻氨基酚敏感膜传感器   总被引:6,自引:0,他引:6  
研制了电化学聚合制备尼古丁分子印迹聚邻氨基酚敏感膜传感器,并对分子印迹膜的结构和性能进行了探讨与研究.在弱酸性条件下,以邻氨基酚为单体,尼古丁为模板分子,用循环伏安法电聚合成膜制备传感器.该传感器对尼古丁具有良好的选择性和敏感度,用恒电位计时安培法,尼古丁浓度在4.0×10-7~3.3×10-5mol/L范围内与电流增量成线性关系,检测下限为2.0×10-7mol/L,加标回收率在99%~102%之间.  相似文献   

5.
用XRD衍射技术分析了基片转动和充氧条件对ZrO2薄膜组成结构的影响,发现在相同低氧压条件下(P≤1.1×10-2Pa)基片转动能够改变薄膜的组成结构,即薄膜发生从四方相到单斜相的转变;随着氧压进一步升高,ZrO2薄膜将由多晶态逐渐转变为无定形结构.同时发现基片转动能够降低充氧条件对表面粗糙度和晶粒大小的影响.激光阈值损伤测量表明,氧压条件影响着ZrO2薄膜的抗激光损伤能力,且多晶结构的激光损伤阈值高于无定形结构.  相似文献   

6.
论述了ITO膜的导电机理及生长机理,讨论了电子束加热真空蒸镀ITO膜的方法中,膜的组分、氧分压、衬底温度和蒸发速率等几个参数对ITO膜光电性能的影响.在选择合适的工艺条件下制备ITO膜,电阻率约4×10-4Ω·cm,可见光范围内平均透过率高于90%.  相似文献   

7.
固相法合成负热膨胀性粉体ZrW2O8   总被引:24,自引:6,他引:18  
以分析纯ZrO2和WO3为原料,用固相法制备了负热膨胀材料ZrW2O8粉体.以X射线粉末衍射、扫描电子显微镜分别对粉体进行物相分析和形貌观测;通过高温X射线衍射以及Powder X软件计算不同温度下的晶胞参数,从而确定热膨胀系数.结果表明经1 220℃保温3 h制备出的高纯度ZrW2O8粉体为单一立方结构,平均粒径为0.5μm;ZrW2O8粉体有显著的负热膨胀特性,在室温到150℃范围内,所得ZrW2O8粉体热膨胀系数为-11.58×10-6K-1;200~500℃范围内,热膨胀系数为-3.77×10-6K-1;在整个温度范围内平均热膨胀系数为-6.31×10-6K-1.  相似文献   

8.
磁控溅射ITO透明导电薄膜的研究   总被引:4,自引:0,他引:4       下载免费PDF全文
采用直流磁控反应溅射法制备锡掺杂氧化铟 ( I T O) 薄膜, 研究了不同的基片温度、氧分压等工艺参数对 I T O 薄膜电学、光学性能的影响, 制备出方块电阻为20 - 50 Ω、可见光透射率高于86 % 的 I T O 薄膜  相似文献   

9.
电子束法沉积ITO透明导电膜的研究   总被引:5,自引:0,他引:5  
论述了ITO膜的导电机理及生长机理,讨论了电子束加热真空蒸镀ITO膜的方法中,膜的组分,氧分压,衬底温度和蒸发速率等几个参数对ITO膜光电性能的影响,在选择合适的工艺条件下制备ITO膜,电阻率约4×10^-4Ω·cm,可见光范围内平均透过率高于90%。  相似文献   

10.
通过固相烧结法制备了Bi2CuO4材料,并对其在中高温下的电导性能及氧渗透性能进行了研究.研究表明,Bi2CuO4在700℃以下时为电子导体,而在700℃以上时其离子电导随温度的增加而显著的增加,在780℃左右时与其电子电导相当,是一种较好的氧离子-电子混合导体.氧渗透测量表明在786℃时,厚度为1.72mm的样品在上表面氧分压为0.209atm,下表面氧分压为0.006atm时的氧渗透率达到5.93×10-8mol/scm2.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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