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41.
Rafael Rojas-Hernndez Juan Luis Díaz-de-Len-Santiago Grettel Barcel-Alonso Jorge Bautista-Lpez Valentin Trujillo-Mora Julio Csar Salgado-Ramírez 《Entropy (Basel, Switzerland)》2022,24(7)
This paper introduces a new method of compressing digital images by using the Difference Transform applied in medical imaging. The Difference Transform algorithm performs the decorrelation process of image data, and in this way improves the encoding process, achieving a file with a smaller size than the original. The proposed method proves to be competitive and in many cases better than the standards used for medical images such as TIFF or PNG. In addition, the Difference Transform can replace other transforms like Cosine or Wavelet. 相似文献
42.
The microwave spectrum has been investigated for the molecule of Benzenesulphonyl chloride within the 8–18 Ghz frequency region. Several a and b type bands corresponding to the Cl35 and Cl37 Isotopes were observed and assigned. We have also used the CNDO/2 method in order to estimate some molecular parameters and the dipole moment. The theoretical calculation and the experimental data have been joined to derive a reliable structure of the molecule concluding that the Cl is located on the plane of the benzene ring. 相似文献
43.
Vitor Matos Julio D. Silva Dan Marchesin 《Bulletin of the Brazilian Mathematical Society》2016,47(2):545-559
Themain goal of ourwork is to showthat there exists a class of 2×2 Riemann problems for which the solution comprises a singlewave group for an open set of initial conditions. This wave group comprises a 1-rarefaction joined to a 2-rarefaction, not by an intermediate state, but by a doubly characteristic shock, 1-left and 2-right characteristic. In order to ensure that perturbations of initial conditions do not destroy the adjacency of the waves, local transversality between a composite curve foliation and a rarefaction curve foliation is necessary. 相似文献
44.
Unexpected reactivity of pyridinium salts toward alkynyl Fischer complexes to produce oxo‐heterocycles 下载免费PDF全文
María Inés Flores‐Conde Fabiola N. de la Cruz Julio López J. Óscar C. Jiménez‐Halla Eduardo Peña‐Cabrera Marcos Flores‐Álamo Francisco Delgado Miguel A. Vázquez 《应用有机金属化学》2018,32(3)
The unprecedented reaction of ketone‐containing aromatic pyridinium salts 3a ‐ e and alkynyl Fischer complexes 1a ‐ f proceeds via a mild domino process to provide 4,6‐disubstituted pyran‐2‐ones 5a ‐ k and 2,3,5‐trisubstituted furans 6a ‐ h (45‐97%). According of the results of isotopic labeling experiments, a mechanism involving an initial Michael addition appears to be the key step, obtaining a mesomeric structure responsible for the formation of both products. 相似文献
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Braga Renata M. Melo Dulce M. A. Melo Marcus A. F. Freitas Julio C. O. Boateng Akwasi A. 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6655-6663
Journal of Thermal Analysis and Calorimetry - Elephant grass (Pennisetum purpureum Schum.) is one such resource with a great amount of carbohydrate and lignin polymers that together represent high... 相似文献