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991.
992.
993.
Elena Binkauskiene Albinas Lugauskas Malle Krunks Ilona Oja Acik Vitalija Jasulaitiene Gintautas Saduikis 《Synthetic Metals》2010,160(9-10):906-910
The growth of Chrysosporium merdarium on TiO2 (rutile, anatase) and its possibility to deteriorate the surface were investigated. Treated with fungi and untreated samples of deteriorated TiO2 surfaces were studied by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Microbial deterioration of TiO2 is also discussed. The attachment to the TiO2 surface via metabolic products resulted in the formation of cryptand [2,2,2] complex with Ca2+ ions. According to water contact angle (CA) measurements microbial growth increases the wettability of TiO2 film surfaces. A much more intensive fungal action during microbial treatment on rutile in comparison with that of anatase was observed. A chemical deterioration product, the volatile trimethyl borate, on rutile in exudation of C. merdarium was detected by gas chromatographic–mass spectrometric analysis. 相似文献
994.
Vanesa Calvino-Casilda Elena Pérez-Mayoral Rosa M. Martín-Aranda Zuzanna Zienkiewicz Izabela Sobczak Maria Ziolek 《Topics in Catalysis》2010,53(3-4):179-186
The present paper discloses a new alternative method for the isomerization of eugenol to isoeugenol where mesoporous materials containing niobium are used as solid base catalysts, affording good yields of isomerized product and being environmentally friendly. Nb-containing MCM-41 mesoporous materials were modified with alkaline cations (Li, Na, K, Rb and Cs) and characterized by BET, FTIR, XRD, and UV–vis techniques. The prepared materials were tested in the isomerization of eugenol to isoeugenol by sonochemical and thermally-activated reactions. Li, Na, K, Rb, and Cs/NbMCM-41 catalysts are active catalyst for the preparation of isoeugenol, and selective to the trans-isomer. Rb/NbMCM-41 sample is the optimum catalysts for the reaction. This result is in accordance with the calculated basicity observed during the Knoevenagel probe reaction of basicity. Conversions around 90% are obtained when using Rb-NbMCM-41 catalysts, with 90% selectivity to trans-isoeugenol, under ultrasound activation. In contrast, conversion around 72% with 90% selectivity is attained under classical thermal activation. The catalysts were reused four times without a substantial decrease of activity. 相似文献
995.
The purpose of this paper is to discuss the results of analysis of two-phase flow in horizontal tubes. Two flow situations have been considered: gas/liquid flow in a long straight pipe, and similar flow conditions in a pipe with 90° elbow. The theoretical approach utilizes a multifield modeling concept. A complete three-dimensional two-phase flow model has been implemented in a state-of-the-art computational multiphase fluid dynamics (CMFD) computer code, NPHASE. The overall model has been tested parametrically. Also, the results of NPHASE simulations have been compared against experimental data for a pipe with 90° elbow. 相似文献
996.
997.
Elena L. Belokoneva 《Crystallography Reviews》2013,19(3):151-198
The crystal chemical analysis of the class of borates has been carried out using the extended Dornberger-Schiff order–disorder (OD) theory based on the recognition of building blocks of various dimensions. All of the borate structures are built from several fundamental building blocks typical for every group of hexa-, penta-, tetra-, tri-, diborates; polyborates contain combinations of these different units. Zero dimensional periodic blocks and the fundamental building blocks in the Christ, Clark, and Strunz systems are in fact the same. Every block possesses its own topology and local symmetry. Consecutive condensation of blocks to rods, layers and frameworks is governed by symmetry laws, that is together with the local symmetry of units the subject of OD-analysis. For all borate groups considered, symmetry groupoids of various ranks have been proposed for different condensation units. Structural-generic branches for borates have been distinguished, hypothetical structural variants predicted, and the positions of compounds in the Strunz system either confirmed or corrected. Successful application of symmetry-topological principles of extended OD-theory to the borates gives a tool for crystal chemical analysis of many other compound classes. 相似文献
998.
Stanislav Naryzhny Natalia Ronzhina Elena Zorina Fedor Kabachenko Maria Zavialova Viktor Zgoda Nikolai Klopov Olga Legina Rimma Pantina 《International journal of molecular sciences》2021,22(12)
Haptoglobin (Hp) is a blood plasma glycoprotein that plays a critical role in tissue protection and the prevention of oxidative damage. Haptoglobin is an acute-phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein and is the subject of research as a potential biomarker of many diseases, including malignant neoplasms. The Human Hp gene is polymorphic and controls the synthesis of three major phenotypes—homozygous Hp1-1 and Hp2-2, and heterozygous Hp2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual’s predisposition to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). Glioblastoma multiform (GBM) is the most malignant primary brain tumor. In our study, we have analyzed the state of Hp proteoforms in plasma and cells using 1D (SDS-PAGE) and 2D electrophoresis (2DE) with the following mass spectrometry (LC ES-MS/MS) or Western blotting. We found that the levels of α2- and β-chain proteoforms are up-regulated in the plasma of GBM patients. An unprocessed form of Hp2-2 (PreHp2-2, zonulin) with unusual biophysical parameters (pI/Mw) was also detected in the plasma of GBM patients and glioblastoma cells. Altogether, this data shows the possibility to use proteoforms of haptoglobin as a potential GBM-specific plasma biomarker. 相似文献
999.
Elena Bartkiene Gerhard Schleining Toma Rekstyte Vita Krungleviciute Grazina Juodeikiene Lina Vaiciulyte‐Funk Zita Maknickiene 《International Journal of Food Science & Technology》2013,48(12):2613-2620
The aim of this research was to study the effects of solid‐state fermentation (SSF) with Lactobacillus sakei, Pediococcus pentosaceus and P. acidilactici on lupine sourdough parameters and lupine sourdough influence on the physical dough properties and wheat bread quality. The results showed that lactic acid bacteria (LAB) significantly reduced the pH and increased total titratable acidity (TTA) of SSF lupine. The highest protease activity in lupine is excreted by L. sakei (187.1 ± 8.6 PU g?1), and the highest amylase activity, by P. pentosaceus (155.8 ± 7.5 AU g?1). Lupine sourdough has a significant effect on the rheological properties of doughs, which affect the baking characteristics of the final product. In conclusion, it can be said that L. sakei, P. pentosaceus and P. acidilactici could be used for lupine SSF, and the addition of up to the 10% SSF lupine products increases the wheat–lupine bread quality. 相似文献
1000.
Gonzalez-Barahona J.M. de-las-Heras-Quiros P. Centeno-Gonzalez J. Matellan-Olivera V. Ballesteros F.J. 《Software, IEEE》2000,17(3):76-79
In 1993, the authors began using 386BSD (which was libre software, or freeware) to teach computer science classes at Madrid's Carlos III University, in Spain. Seven years later, NetBSD and GNU/Linux are the operating systems of choice for several of the university's computer science teaching laboratories 相似文献