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991.
Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution.In this article,a look-up table method based on multi-axis differential optical absorption spectroscopy(MAX-DOAS)technology is established for retrieving the tropospheric NO2 vertical distribution profiles.This method retrieves the aerosol extinction profiles with minimum cost function.Then,the aerosol extinction profiles and the atmospheric radiation transfer model(RTM)are employed to establish the look-up table for retrieving the NO2 vertical column densities(VCDs)and profiles.The measured NO2 differential slant column densities(DSCDs)are compared with the NO2 DSCDs simulated by the atmospheric RTM,and the NO2 VCDs,the weight factor of NO2 in the boundary layer,and the boundary layer height are obtained by the minimization process.The look-up table is established to retrieve NO2 VCDs based on MAX-DOAS measurements in Huaibei area,and the results are compared with the data from Copernicus Atmospheric Monitoring Service(CAMS)model.It is found that there are nearly consistent and the correlation coefficient R2 is more than 0.86.The results show that this technology provides a more convenient and accurate retrieval method for the stereoscopic monitoring of atmospheric environment. 相似文献
992.
Wake-up effect in Hf0.4Zr0.6O2 ferroelectric thin-film capacitors under a cycling electric field 下载免费PDF全文
We examined the wake-up effect in a TiN/Hf0.4Zr0.6O2/TiN structure. The increased polarization was affected by the cumulative duration of a switched electric field and the single application time of the field during each switching cycle. The space-charge-limited current was stable, indicating that the trap density did not change during the wake-up. The effective charge density in the space-charge region was extracted from capacitance-voltage curves, which demonstrated an increase in free charges at the interface. Based on changing characteristics in these properties, the wake-up effect can be attributed to the redistribution of oxygen vacancies under the electric field. 相似文献
993.
Chuichiro Hayashi 《代数通讯》2013,41(9):3340-3349
We introduce a notion of natural orderings of elements of connected finite quandles. Let Q be such a quandle of order n. Any automophism on Q is a natural ordering when the elements are already ordered naturally. Suppose that the permutation *q is a cycle of length n ? 1. Then, the operation tables for such orderings coincide, which leads to the classification of automorphisms on Q. Moreover, every row and column of the operation table contains all the elements of such a quandle, which is due to K. Oshiro. We also consider the general case of finite connected quandles. 相似文献
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The main aim of this paper is to construct the character tables of the parabolic subgroups of the Chevalley groups G 2(q), where q is a power of a prime p > 3. 相似文献
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This paper is concerned with global in time behavior of solutions for a quasilinear Petrovsky inverse source problem with boundary dissipation. We establish a stability result when the integral constraint vanishes as time goes to infinity. We also show that the smooth solutions blow up when the data is chosen appropriately. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Jamel Benameur 《Mathematical Methods in the Applied Sciences》2013,36(2):143-153
Kato, Ponce, Beale and Majda prove the existence and uniqueness of maximal solution of Euler and Navier–Stokes equations and some blow‐up criterion. In the periodic case, we establish that if the maximum time T* is finite, then the growth of is at least of the order of (T* ? t)?2m / 5. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献