基于数字图像相关的透明材料厚度测量

提出了一种测定透明材料厚度的新方法。该方法是基于透明材料对光的折射特点,利用光斑点面内位移与材料厚度的变化关系,将厚度的测量转化为对面内位移的测量。将此方法与数字图像相关法相结合,实现了单摄像机对厚度的测定。对轴向拉伸状态下的有机玻璃板的厚度变化进行了测定,将实验结果与理论值进行了对比,两者符合较好,证明了该实验方法的有效性和可行性。     

介质厚度对光量子阱束缚态波长的调整

用传输矩阵法计算了不同介质厚度对光量子阱结构的传输特性。计算结果表明:光子的束缚效应将导致波长的量子化。通过微小地改变阱区和垒区介质的厚度可改变束缚态的波长,且阱区和垒区介质厚度的变化与束缚态波长的变化呈良好的线性关系,阱区介质厚度的变化对束缚态波长的变化大于垒区。阱区介质厚度与束缚态半峰宽呈阶梯形状降低,而阱区介质厚度与束缚态品质因子呈阶梯形状升高。此结果为设计所需要的束缚态波长光量子阱结构提供了理论依据,也为光量子阱实现热敏开关提供了理论基础。     

Effect of film thickness manganite-based on interfacial barrier of heterojunctions

Interracial barrier is a key factor that determines the performances of heterojunctions. In this work, we study the effect of manganite film thickness on the effective interracial barrier for La0.67Sr0.33MnO3/Nb：SrTiO3 junctions, The barrier is extracted from the forward current-voltage characteristics. Our results demonstrate that the barrier decreases gradually from -0.85 eV to -0.60 eV when the film thickness decreases from 150 nm to 2 nm. The overall value of the barrier is only about 50% of the corresponding one determined from the photovoltaic effect.     

A revisit to the neutron skin thickness of neutron-rich nuclei in the statistical abrasion ablation model

The cross sections of the fragments produced in the projectile fragmentation reactions of the even calcium isotopes from A=36 to A=52 are calculated using the statistical abrasion ablation model.The neutron skin thickness are studied by investigating the fragments isotopic cross section distributions.The neutron-skin thicknesses of the calcium isotopes have a good linear correlation to the peak positions of their fragment isotopic cross section distributions.The correlation between the neutron skin thickness and the neutron density distributions of 48 Ca is investigated by introducing a parameter to adjust the diffuseness parameter in the fermi-type density distribution.     

Employing a Cerenkov detector for the thickness measurement of X-rays in a scattering background

The variation in environmental scattering background is a major source of systematic errors in X- ray inspection and measurement systems. As the energy of these photons consisting of environmental scattering background is much lower generally, the Cerenkov detectors having the detection threshold are likely insensitive to them and able to exclude their influence. A thickness measurement experiment is designed to verify the idea by employing a Cerenkov detector and an ionizing chamber for comparison. Furthermore, it is also found that the application of the Cerenkov detectors is helpful to exclude another systematic error from the variation of low energy components in the spectrum incident on the detector volume.     

Numerical Study on Open-Circuit Voltage of Single Layer Organic Solar Cells with Schottky Contacts: Effects of Molecular Energy Levels, Temperature and Thickness

We numerically investigate the effects of the exciton generation rate G, temperature T, the active layer thickness d and the position of LUMO level EL related to the cathode work function Wc at a given energy gap on the opencircuit voltage Voc of single layer organic solar cells with Schottky contact. It is demonstrated that open-circuit voltage increases concomitantly with the decreasing cathode work function Wc for given anode work functions and exciton generation rates. In the case of given cathode and anode work functions, the open-circuit voltage first increases with the exciton generation rate and then reaches a saturation value, which equals to the builtin voltage. Additionally, it is worth noting that a significant improvement to Voc could be made by selecting an organic material which has a relative high LUMO level （low ｜EL｜ value）. However, Voc decreases as the temperature increases, and the decreasing rate reduces with the enhancement of exeiton generation rate. Our study also shows that it is of no benefit to improve the open-circuit voltage by increasing the device thickness because of an enhanced charge recombination in thicker devices.     

黄河河道冰水情定点连续自动检测及数据分析

根据黄河中上游流域冰水情监测以及预防凌汛灾害的需求,设计了一种适合黄河河道的冰水情自动测报系统.该系统由基于空气、冰与水电阻特性差异的冰层厚度传感器、DS18B20的温度梯度传感器以及智能处理仪构成.采用该系统在内蒙托克托县黄河河道进行了黄河封冻期河道冰层厚度连续监测试验,获取了大量的现场实测数据,对采样数据进行分析,提出了判别冰层厚度的平均滤波算法,实现了对冰层生消变化全过程的自动监测.     

声光可调近红外光谱技术快速检测再造烟叶的厚度

厚度是衡量再造烟叶品质及稳定性的一项重要指标,目前再造烟叶厚度测定方法存在读数不稳定、测量准确性受样品特性影响,不利于检测和控制.本文应用声光可调滤光器近红外光谱仪建立再造烟叶厚度检测方法模型,能准确预测再造烟叶厚度指标,具有准确性好,精密度高的特点,符合再造烟叶厚度检测的需要.     

等效求解电介质球内退极化场的前提的证明

求解均匀极化的电介质球内的退极化场时,由于球面上极化面电荷分布不均匀,一般都用两等大、原本重叠、带均匀等量异号电荷的球体错开微小位移的模型来等效地求解;但这种模型为何与原情景等效,是令初学者困惑的地方.对此,文章给出了一个简单的证明.     

沟道层厚度对室温制备的In2O3薄膜晶体管器件性能的影响

在室温下采用直流磁控溅射以SiO₂/Si为衬底制备了不同沟道层厚度的底栅式In₂O₃薄膜晶体管,讨论了沟道层厚度对底栅In₂O₃薄膜晶体管的电学性能的影响。实验结果表明:器件的特性与沟道层厚度有关,最优沟道层厚度的In₂O₃薄膜晶体管为增强型,其阈值电压为2.5 V,开关电流比约为10⁶,场效应迁移率为6.2 cm²·V^-1·s^-1。