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81.
Irek I. Mukhamatdinov Sergey A. Sitnov Olga V. Slavkina Konstantin A. Bugaev Alexander V. Laikov 《Petroleum Science and Technology》2019,37(12):1410-1416
In this paper, we investigated the influence of steam treatment on structural group composition of resins and asphaltenes of heavy oil. The object of investigation was oil-saturated rocks from Riphean-Vendian complex. The extracted crude oil was determined as a high-viscous fluid. The resins and asphaltenes destructed in a small extent due to thermal treatment. The oil-soluble iron-based catalyst intensified the destructive processes. The content of sulfur compounds (-SO) in resins and asphaltenes drastically decreased due to reduction reaction of sulfoxide to sulfide and hydrogen sulfide. The results showed that catalytic aquathermolysis, even at low temperature ranges, promoted the cracking reaction of most macromolecular components and increased the content of light fractions of heavy oil. Consequently, it reduced its viscosity. 相似文献
82.
Prof. Chiara Brullo Dr. Federica Rapetti Prof. Silvana Alfei Dr. Irena Maric Dr. Francesca Rizzelli Dr. Marina Mapelli Dr. Camillo Rosano Dr. Maurizio Viale Prof. Olga Bruno 《ChemMedChem》2020,15(11):961-969
Even though immunotherapy has radically changed the search for anticancer therapies, there are still many different pathways that are open to intervention with traditional small molecules. To expand our investigation in the anticancer field, we report here a new series of compounds in which our previous pyrazole and imidazopyrazole scaffolds are linked to a differently decorated phenyl ring through an acylhydrazone linker. Preliminary tests on the library were performed at the National Cancer Institute (USA) against the full NCI 60 cell panel. The best compounds among the imidazopyrazole series were then tested by immunofluorescence staining for their inhibition of cell proliferation, apoptosis induction, and their effect on the cell cycle and on microtubules. Two compounds, in particular 4-benzyloxy-3-methoxybenzyliden imidazopyrazole-7-carbohydrazide showed good growth inhibition, with IC50 values in the low-micromolar range, and induced apoptosis. Both compounds altered the cell-cycle phases with the appearance of polyploid cells. Immunofluorescence analysis evidenced microtubules alterations; tubulin polymerization assays and docking studies suggested the tubulin system to be the possible, although not exclusive, target of the new acylhydrazone series reported here. 相似文献
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84.
Alena Yarysheva Dmitry Strel'tsov Sergey Malakhov Olga Arzhakova Larisa Yarysheva Alexandr Volynskii 《Polymer International》2020,69(7):627-634
This work addresses the phenomenon of the development of a patterned surface relief on polymer films via different modes of environmental crazing. Commercial films of semicrystalline poly(tetrafluoroethylene) (PTFE) and amorphous glassy poly(ethylene terephthalate) (PET) were subjected to tensile drawing in the presence of physically active liquid environments (carbon tetrachloride or aliphatic alcohols). The structure parameters and wettability of the modified films were studied by AFM, SEM, profilometer measurements and contact angle measurements. Environmental intercrystallite crazing of PTFE is accompanied by the development of an unstable structure with a high free surface, which experiences marked strain recovery upon unloading. As a result of the relief formation, PTFE hydrophobicity is enhanced (the water contact angle increases by 25°). Classical environmental crazing of PET films is accompanied by the formation of an anisotropic surface relief which is an assembly of crazes oriented perpendicular to the direction of tensile drawing, thus leading to the phenomenon of anisotropic wetting. The proposed approach for structural surface modification makes it possible to use the advantages of surface instability and spontaneous self‐organization of the polymer towards the development of a unique surface microrelief. © 2020 Society of Chemical Industry 相似文献
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88.
Xixiang Zhu Hengxing Xu Yongtao Liu Jia Zhang Miaosheng Wang Ilia N. Ivanov Olga S. Ovchinnikova Bin Hu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(49)
A new approach to generate a two‐photon up‐conversion photoluminescence (PL) by directly exciting the gap states with continuous‐wave (CW) infrared photoexcitation in solution‐processing quasi‐2D perovskite films [(PEA)2(MA)4Pb5Br16 with n = 5] is reported. Specifically, a visible PL peaked at 520 nm is observed with the quadratic power dependence by exciting the gap states with CW 980 nm laser excitation, indicating a two‐photon up‐conversion PL occurring in quasi‐2D perovskite films. Decreasing the gap states by reducing the n value leads to a dramatic decrease in the two‐photon up‐conversion PL signal. This confirms that the gap states are indeed responsible for generating the two‐photon up‐conversion PL in quasi‐2D perovskites. Furthermore, mechanical scratching indicates that the different‐n‐value nanoplates are essentially uniformly formed in the quasi‐2D perovskite films toward generating multi‐photon up‐conversion light emission. More importantly, the two‐photon up‐conversion PL is found to be sensitive to an external magnetic field, indicating that the gap states are essentially formed as spatially extended states ready for multi‐photon excitation. Polarization‐dependent up‐conversion PL studies reveal that the gap states experience the orbit–orbit interaction through Coulomb polarization to form spatially extended states toward developing multi‐photon up‐conversion light emission in quasi‐2D perovskites. 相似文献
89.
lvaro Hernez Albert Sanllorente Olga Castaer Miguel . Martínez‐Gonzlez Emilio Ros Xavier Pint Ramn Estruch Jordi Salas‐Salvad Dolores Corella ngel M. Alonso‐Gmez Lluis Serra‐Majem Miquel Fiol Jos Lapetra Enrique Gmez‐Gracia Rafael de la Torre Rosa‐María Lamuela‐Ravents Montserrat Fit 《Molecular nutrition & food research》2019,63(6)
90.
Robert?C.?Soliva-Fortuny Olga?Martín-BellosoEmail author 《European Food Research and Technology》2003,217(1):4-9
Fresh-cut Conference pears were packaged under different modified atmosphere packaging (MAP) conditions and stored in refrigeration. The effects of packaging atmospheres on the microbial viability as well as on the changes in acidity, sugars and ascorbic acid (AA) were studied throughout storage. The use of plastic bags of a permeability of 15 cm 3 O 2 m -2bar -1 24 h -1 and initial atmospheres of 0 kPa O 2 extended the microbiological shelf life of pear cubes for at least 3 weeks of storage. Under these conditions, AA levels were kept almost unvaried throughout storage due to the restrictions in the O 2 availability inside the bags' headspaces. However, these conditions also triggered physiological and biochemical changes that caused greater changes in the product acidity. The sugar profile was also affected by storage, but MAP did not show any significant influence on the reported changes. 相似文献