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121.
Alexandru C. Razus Liviu Birzan Claudia Pavel Oana Lehadus Andreea Cristina Corbu Cristian Enache 《Journal of heterocyclic chemistry》2006,43(4):963-977
122.
Ladybug taint (also known as ladybird taint) is a relatively recently recognized fault that has been identified in wines from a wide range of terroirs. Alkyl-methoxypyrazines—particularly 2-isopropyl-3-methoxypyrazine—have been determined as the causal compounds, and these are introduced into grape must during processing, when specific species of vineyard-dwelling Coccinellidae are incorporated into the harvested fruit. Coccinella septempunctata, and especially the invasive Harmonia axyridis, are the beetles implicated, and climate change is facilitating wider dispersal and survivability of H. axyridis in viticultural regions worldwide. Affected wines are typically characterized as possessing excessively green, bell pepper-, and peanut-like aroma and flavor. In this paper, we review a range of vineyard practices that seek to reduce Coccinellidae densities, as well as both “standard” and novel wine treatments aimed at reducing alkyl-methoxypyrazine load. We conclude that while prevention of ladybug taint is preferable, there are several winery interventions that can remediate the quality of wine affected by this taint, although they vary in their relative efficacy and specificity. 相似文献
123.
Raluca Turdean Elena Bogdan Anamaria Terec Anca Petran Laurian Vlase Ioan Turcu Ion Grosu 《Central European Journal of Chemistry》2009,7(1):111-117
The synthesis of new 3,7-dibromophenothiazine derivatives bearing bromoalkyl, mercaptoalkyl and alkylthioacetate groups on
the N atom at position 10 is reported. The Suzuki coupling reaction of one of these derivatives via the bromine atoms at positions
3 and 7 with bromothiophene derivatives is also discussed.
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124.
Datta T Yin M Dimofte A Bleiweiss M Lungu A Amirzadeh J Sharp WE 《Physical review letters》2003,91(10):109001; author reply 109002
125.
Alexandru C. Razus Liviu Birzan Claudia Pavel Oana Lehadus Andreea Corbu Filip Chiraleu Cristian Enache 《Journal of heterocyclic chemistry》2007,44(1):245-250
126.
Alexandru C. Razus Liviu Birzan Claudia Pavel Oana Lehadus Andreea Corbu Filip Chiraleu Cristian Enache 《Journal of heterocyclic chemistry》2007,44(1):251-260
127.
N,N'-Disubstituted methylenediimidazolium salts allow the formation of flexible inclusion complexes with beta-cyclodextrin, cucurbit[7]uril, tetrapropoxycalix[4]arene, and dibenzo-24-crown-8 ether. Due to the salt nature of the imidazolium guest, the counterion largely determines its solubility in a given solvent. Moreover, by the judicious choice of the imidazolium substituents, inclusion complexes of guest salts were obtained with a variety of macrocyclic hosts, and the binding parameters of the inclusion were determined for each complex. 相似文献
128.
Andreea Celia Benchea Daniela Babusca Črtomir Podlipnik Dan Gheorghe Dimitriu 《Analytical letters》2017,50(17):2711-2724
ABSTRACTQuantum-mechanical characterization for methyl red was performed using density function theory. The dipole moment and polarizability in the ground state of methyl red were theoretically calculated. The contribution of intermolecular interactions to spectral shifts in solution and the limits in which the excited states’ dipole moment vary in the neutral form were established by a solvatochromic study. The solvatochromism of the acid and alkaline forms of methyl red was experimentally measured and compared with calculated spectra. 相似文献
129.
Ancua Ctlina Fia Ana Andreea Secreanu Adina Magdalena Musuc Emma Adriana Ozon Iulian Sarbu Irina Atkinson Adriana Rusu Erand Mati Valentina Anuta Anca Lucia Pop 《Molecules (Basel, Switzerland)》2022,27(19)
The present study aims to demonstrate the influence of the polymer-carrier type and proportion on the quality performance of newly developed oral immediate-release tablets containing amiodarone solid dispersions obtained by hot-melt extrusion. Twelve solid dispersions including amiodarone and different polymers (PEG 1500, PEG 4000; PEG 8000, Soluplus®, and Kolliphor® 188) were developed and prepared by hot-melt extrusion using a horizontal extruder realized by the authors in their own laboratory. Only eleven of the dispersions presented suitable physical characteristics and they were used as active ingredients in eleven tablet formulations that contain the same amounts of the same excipients, varying only in solid dispersion type. The solid dispersions’ properties were established by optical microscopy with reflected light, volumetric controls and particle size evaluation. In order to prove that the complex powders have appropriate physical characteristics for the direct compression process, they were subjected to different analyses regarding their flowability and compressibility behavior. Additionally, the Fourier transform infrared spectroscopy and X-ray diffraction analysis were performed on the obtained solid dispersions. After confirming the proper physical attributes for all blends, they were processed into the form of tablets by direct compression technology. The manufactured tablets were evaluated for pharmacotechnical (dimensions–diameter and thickness, mass uniformity, hardness and friability) and in vitro biopharmaceutical (disintegration time and drug release) performances. Furthermore, the influence of the polymer matrix on their quality was determined. The high differences in flow and compression performances of the solid dispersions prove the relevant influence of the polymer type and their concentration-dependent plasticizing properties. The increase in flowability and compressibility characteristics of the solid dispersions could be noticed after combining them with direct compression excipients owning superior mechanical qualities. The influence of the polymer type is best detected in the disintegration test, where the obtained values are quite different between the studied formulations. The use of PEG 1500 alone or combined in various proportions with Soluplus® leads to rapid disintegration. In contrast, the mixture of PEG 4000 and Poloxamer 188 in equal proportions determined the increase in disintegration time to 120 s. The use of Poloxamer 188 alone and a 3:1 combination of PEG 4000 and Soluplus® also generates a prolonged disintegration time for the tablets. 相似文献
130.
Zaharescu Traian Mateescu Carmen Dima Andreea Varca Gustavo H. C. 《Journal of Thermal Analysis and Calorimetry》2022,147(1):327-336
Journal of Thermal Analysis and Calorimetry - In this paper, ecological-friendly materials based on ethylene–propylene–diene terpolymer (EPDM) with improved thermal and radiation... 相似文献