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261.
Marina Dana Ţopa Norbert Toma Botond Sandor Kirei Ioana Homana Marius Neag Gilbert De Mey 《Acoustical Physics》2011,57(2):199-207
The paper presents the acoustics analysis of three different enclosed spaces. These spaces (rooms) have different geometrical
shapes and sizes and serve for different purposes. The early decay time, reverberation time, clarity and center time are evaluated
with Dirac, WinMLS, Aurora and Caracad software using simple, low-cost equipment. The listed acoustic parameters were determined
using linear sine sweep and impulsive sources. Comparisons between experimental measurements, simulations and analytic results
were done. The room impulse response measurement proved to be the most reliable method to evaluate the properties of different
rooms even if the measurements are perturbed by non-idealities of the low-cost equipment. 相似文献
262.
Alexandra-Elisabeta Stamate Rodica Zvoianu Octavian Dumitru Pavel Ruxandra Birjega Andreea Matei Marius Dumitru Ioana Brezetean Mariana Osiac Ioan-Cezar Marcu 《Molecules (Basel, Switzerland)》2021,26(20)
Mechanical activation and mechanochemical reactions are the subjects of mechanochemistry, a special branch of chemistry studied intensively since the 19th century. Herein, we comparably describe two synthesis methods used to obtain the following layered double hydroxide doped with cerium, Mg3Al0.75Ce0.25(OH)8(CO3)0.5·2H2O: the mechanochemical route and the co-precipitation method, respectively. The influence of the preparation method on the physico-chemical properties as determined by multiple techniques such as XRD, SEM, EDS, XPS, DRIFT, RAMAN, DR-UV-VIS, basicity, acidity, real/bulk densities, and BET measurements was also analyzed. The obtained samples, abbreviated HTCe-PP (prepared by co-precipitation) and HTCe-MC (prepared by mechanochemical method), and their corresponding mixed oxides, Ce-PP (resulting from HTCe-PP) and Ce-MC (resulting from HTCe-MC), were used as base catalysts in the self-condensation reaction of cyclohexanone and two Claisen–Schmidt condensations, which involve the reaction between an aromatic aldehyde and a ketone, at different molar ratios to synthesize compounds with significant biologic activity from the flavonoid family, namely chalcone (1,3-diphenyl-2-propen-1-one) and flavone (2-phenyl-4H-1benzoxiran-4-one). The mechanochemical route was shown to have indisputable advantages over the co-precipitation method for both the catalytic activity of the solids and the costs. 相似文献
263.
Georgiana Ioana Potra Cicalu Petru Aurel Babes Horia Calniceanu Adelina Popa Gabriela Ciavoi Gilda Mihaela Iova Mariana Ganea Ioana Scrobot 《Molecules (Basel, Switzerland)》2021,26(22)
Periodontal disease and diabetes mellitus are two pathologies that are extremely widespread worldwide and share the feature of chronic inflammation. Carvacrol is a phenolic monoterpenoid, produced by a variety of herbs, the most well-known of which is Origanum vulgare. Magnolol is a traditional polyphenolic compound isolated from the stem bark of Magnolia officinalis, mainly used in Chinese medicine. The purpose of this paper is to review the therapeutic properties of these bioactive compounds, in the treatment of periodontitis and diabetes. Based on our search strategy we conducted a literature search in the PubMed and Google Scholar databases to identify studies. A total of one hundred eighty-four papers were included in the current review. The results show that carvacrol and magnolol have anti-inflammatory, antioxidant, antimicrobial, anti-osteoclastic, and anti-diabetic properties that benefit both pathologies. Knowledge of the multiple activities of carvacrol and magnolol can assist with the development of new treatment strategies, and the design of clinical animal and human trials will maximize the potential benefits of these extracts in subjects suffering from periodontitis or diabetes. 相似文献
264.
Leau Sorina Alexandra Lete Cecilia Marin Mariana del Campo Francisco Javier Diaconu Ioana Lupu Stelian 《Journal of Solid State Electrochemistry》2023,27(7):1755-1766
Journal of Solid State Electrochemistry - The development and analytical applications of electrochemical sensors based on antimony tin oxide (ATO)–Prussian blue (PB) screen-printed electrode... 相似文献