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91.
针对当前聚氨酯灌浆材料在渗漏水治理中存在的问题,提出了依靠堵水环氧灌浆材料和高渗透环氧灌浆材料进行渗漏水治理的新思路。环氧类灌浆材料既能够对混凝土裂缝等缺陷进行修复,也能够封堵渗漏水,希望修复后的缺陷能够保持和恢复混凝土结构的耐久性。 相似文献
92.
93.
Penetration depth and spatial resolution of Raman hyperspectral imaging system were studied for effective detection of benzoyl peroxide in flour. The determinations of parameters were achieved by using the single-band background-correct image of a benzoyl peroxide Raman characteristic band and a simple threshold method. The selected parameters were used to detect mixture samples with different concentrations. Percentage of detected benzoyl peroxide pixels was positively correlated to its concentration. The result shows that parameters selected in this study are effective for the detection of benzoyl peroxide additive in flour and can be used for quantitative analysis in the future. 相似文献
94.
A different approach, aiming to achieve the constant blur status of point-spread function (PSF) at a certain defocused plane,
is described. The correlation between the two PSF is used to control the PSF blur similarity, and simultaneously the Strehl
ratio is also used to control the PSF blur minimization. By designing the PSF so that it is significantly insensitive to defocus
or related defocus quantity, for example, due to temperature change, all the constantly blurred images can be accurately de-blurred
by a simple inverse restoration filter for an adequate range of defocus. We refer to that as “software lens compensation”
and apply a design method to solve the athermalization of middle wavelength infrared (MWIR) imaging systems. The resultant
PSF is almost invariant in the temperature range from −10 to 50°C at the same focal plane. Consequently, the constant blur
spot can be removed by a simple digital signal processing. Thus, clear and sharp de-blurred images at different temperatures
are obtained. 相似文献
96.
In this article, the depth‐averaged transport equations are written in a new way so that it is possible to solve the transport equations for very small water depths. Variables are interpolated into the cell face with two different schemes and, the schemes are compared in terms of computational cost and accuracy. The bed source terms are computed using two different assumptions. The effect of these assumptions on numerical simulations is then investigated. Solutions of transport equations on different types of unstructured triangular grids are compared and, an appropriate choice of grid is suggested. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
97.
A. Hollander L. Hessels P. de Voogt D. van de Meent 《SAR and QSAR in environmental research》2013,24(5-6):457-468
In standard multimedia mass balance models, the soil compartment is modeled as a box with uniform concentrations, which often does not correspond with actual field situations. Therefore, the theoretically expected decrease of soil concentrations with depth was implemented in the multimedia model SimpleBox 3.0. The effects of this implementation on the model outcomes were explored for nine compounds in four environmental compartments. For compounds with a low penetration depth, the new model predicts substantially higher or lower concentrations in the vegetation compartment than the old model. For those compounds, predicted concentrations in surface water and air were higher in the new model, but the deviations from the old model were smaller than in the vegetation compartment. For compounds with a large penetration depth, the model adaptations show little effect. No field study was carried out to validate the results of the model calculations, but we did collect measured data on concentrations in vertical soil profiles from literature. According to those data, we concluded that the implementation of depth dependent soil concentrations might be a useful extension for steady state multimedia mass balance models. More field study has to be carried out to validate the model outcomes. 相似文献
98.
Yidong Zhang Zhenwei Dong Lei Zhao Huijuan Guan 《Surface and interface analysis : SIA》2022,54(6):600-606
ZnO film-based ultraviolet (UV) detector was fabricated by photoassisted peak force tunnel atomic force (PFTUNA) on fluorine tin oxide (FTO) substrate. The PFTUNA current in dark and in UV light was ~0.1 and 2.0 nA, respectively. The UV sensitivity (photocurrent/dark current) is more than 20. The response time and the recovery time are ~0.12 and 0.32 s, respectively. The UV sensing mechanism is that the holes will transport to the ZnO surface to capture the adsorbed oxygen ions to weaken the depletion layer under UV illumination. The PFTUNA current between the tip and the ZnO film is consistent with the Richardson–Schottky (RS) thermionic emission model. 相似文献
99.
Y. Kudriavtsev A. Hernandez R. Asomoza S. Gallardo M. Lopez K. Moiseev 《Surface and interface analysis : SIA》2017,49(2):145-148
We have performed secondary ion mass spectrometry depth profiling analysis of III–V based hetero‐structures at different target temperatures and found that both the surface segregation and surface roughness caused by ion sputtering can be radically reduced if the sample temperature is lowered to ?150 °C. The depth profiling of ‘frozen’ samples can be a good alternative to sample rotation and oxygen flooding used for ultra‐low‐energy depth profiling of compound semiconductors. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
100.
Effect of SIMS ionization probability on depth resolution for organic/inorganic interfaces 下载免费PDF全文
Nicholas J. Popczun Lars Breuer Andreas Wucher Nicholas Winograd 《Surface and interface analysis : SIA》2017,49(10):933-939
Secondary ion mass spectrometry (SIMS) relies on the fact that surface particles ejected from a solid surface are ionized under ion bombardment. By comparing the signal of molecular secondary ions desorbed from an organic film with that of the corresponding sputtered neutral precursor molecules, we investigate the variation of the molecular ionization probability when depth profiling through the film to the substrate interface. As a result, we find notable variations of the ionization probability both at the original surface and in the interface region, leading to a strong distortion of the measured SIMS depth profile. The experiments show that the effect can act in two ways, leading either to an apparent broadening or to an artificial sharpening of the observed film‐substrate transition. As a consequence, we conclude that care must be taken when assessing interface location, width, or depth resolution from a molecular SIMS depth profile. 相似文献