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2,6-Disubstituted benzobisoxazoles have been synthesized by a highly efficient reaction of diaminobenzene diols with various orthoesters. The scope of this new reaction for the synthesis of substituted benzobisoxazoles has been investigated using four different orthoesters. The utility of these compounds as building blocks for the synthesis of conjugated polymers is demonstrated. 相似文献
123.
Malika Lahiani-Skiba Aude Coquard Fréderic Bounoure Philippe Vérité Philippe Arnaud Mohamed Skiba 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):197-201
Mebendazole is an antihelmintic drug, active against many intestinal parasites. Its systemic efficacy is limited by its poor
water solubility. The use of natural or derivatized cyclodextrins permeated to multiply notably its apparent solubility, especially
with permethyl β-cyclodextrine (PM β-CD) (multiplied by 4700). The inclusion complex formation between mebendazole and this
methylated β-cyclodextrin, was characterized by mass spectrometry, powder X-ray diffractometry and Fourier transform infrared
spectroscopy: mebendazole seemed to be included in permethyl β-cyclodextrin by its aromatic rings. To prepare inclusion complex
of mebendazole and PMβ-CD by solvent evaporation, acetone may be used and the ratio using lower amount of cyclodextrin (MBZ:CD,
1:2) should be used. 相似文献
124.
The aim of this work is to automate the interpretation of ultrasonic images during the non-destructive testing (NDT) technique called time-of-flight diffraction (TOFD) to aid in decision making. 相似文献
125.
Djamila Oukacha-Hikem Malika Makhloufi-Chebli Anissa Amar Houria Bouherrou Yahia Rachedi Hacène Meghezzi 《合成通讯》2017,47(6):590-598
The synthesis of new 2-pyrone-based hydrazones has been prepared by the coupling of 6-methyl-2H-furo[3,2-c]pyran-3,4-dione with diazonium salts, obtained by diazotization of aniline derivatives. The structure of all compounds was established by spectroscopic methods, and the structure of the more stable conformer was theoretically confirmed by the potential energy profile analysis. The prepared 2-pyrone-based hydrazone dyes were acetylated and both groups of compounds showed moderate to good radical scavenging activity. 相似文献
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127.
Malika Jallouli Sabrine Arfaoui Anouar Ben Mabrouk Carlo Cattani 《Entropy (Basel, Switzerland)》2021,23(7)
Analysis of the fetal heart rate during pregnancy is essential for monitoring the proper development of the fetus. Current fetal heart monitoring techniques lack the accuracy in fetal heart rate monitoring and features acquisition, resulting in diagnostic medical issues. The challenge lies in the extraction of the fetal ECG from the mother ECG during pregnancy. This approach has the advantage of being a reliable and non-invasive technique. In the present paper, a wavelet/multiwavelet method is proposed to perfectly extract the fetal ECG parameters from the abdominal mother ECG. In a first step, due to the wavelet/mutiwavelet processing, a denoising procedure is applied to separate the noised parts from the denoised ones. The denoised signal is assumed to be a mixture of both the MECG and the FECG. One of the well-known measures of accuracy in information processing is the concept of entropy. In the present work, a wavelet/multiwavelet Shannon-type entropy is constructed and applied to evaluate the order/disorder of the extracted FECG signal. The experimental results apply to a recent class of Clifford wavelets constructed in Arfaoui, et al. J. Math. Imaging Vis. 2020, 62, 73–97, and Arfaoui, et al. Acta Appl. Math. 2020, 170, 1–35. Additionally, classical Haar–Faber–Schauder wavelets are applied for the purpose of comparison. Two main well-known databases have been applied, the DAISY database and the CinC Challenge 2013 database. The achieved accuracy over the test databases resulted in Se = 100%, PPV = 100% for FECG extraction and peak detection. 相似文献
128.
Iyad Karamé Dr. Malika Boualleg Jean‐Michel Camus Dr. Tarun K. Maishal Dr. Johan Alauzun Dr. Jean‐Marie Basset Dr. Christophe Copéret Dr. Robert J. P. Corriu Prof. Dr. Erwan Jeanneau Dr. Ahmad Mehdi Prof. Dr. Catherine Reyé Prof. Dr. Laurent Veyre Chloé Thieuleux Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(44):11820-11823
129.
Solubilities and liquid-liquid equilibrium (LLE) data for (water + ethanol + fluorobenzene) solutions are determined at T = (288.15, 298.15, 308.15) K and atmospheric pressure. The titration method is used to construct the binodal curves. All
measured solubilities and liquid-liquid equilibrium data are reproduced quantitatively by empirical equations and the NRTL
activity coefficient model. The correlated data are consistent to better than 0.3% in phase composition.
The studied temperatures have a small effect on the phase equilibrium properties of the investigated systems. The influence
of water concentration on the distribution coefficient of ethanol in the coexistent liquid phases and on the fluorobenzene
selectivity is important. Practically, fluorobenzene may well be used to produce absolute alcohol. 相似文献
130.
A new synthetic pathway towards pentacyclic steroids was described via a ring-closing metathesis reaction as the key step. 相似文献