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81.
Utepov E. B. Pototskii E. P. Shevtsova V. S. Kattabekov E. N. Abuova R. Zh. Berkinbaeva A. S. 《Metallurgist》2019,63(3-4):286-294
Metallurgist - Steels alloyed with chromium are used for the first time for manufacturing sheet stacker components. Steel with a high chromium content (45X), exhibiting good damping properties,... 相似文献
82.
83.
Daniela Frasca Maria Romero Alain Diaz Denisse Garcia Seth Thaller Bonnie B. Blomberg 《International journal of molecular sciences》2021,22(4)
Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation. 相似文献
84.
Lorena Rodríguez-López Myriam Rincón-Fontán Xanel Vecino Ana B. Moldes Jose M. Cruz 《Journal of surfactants and detergents》2020,23(1):79-90
Over the last few years, the global biosurfactant market has raised due to the increasing awareness among consumers, for the use of biological or bio-based products. Because of their composition, it can be speculated that these are more biocompatible and more biodegradable than their chemical homologous. However, at the moment, no studies exist in the literature about the biodegradability of biosurfactants. In this work, a biosurfactant contained in a crude extract, obtained from a corn wet-milling industry stream that ferments spontaneously in the presence of lactic acid bacteria, was subjected to a biodegradation study, without addition of external microbial biomass, under different conditions of temperature (5–45 °C), biodegradation time (15–55 days), and pH (5–7). For that, a Box–Behnken factorial design was applied, which allowed to predict the percentage of biodegradation for the biosurfactant contained in the crude extract, between the range of the independent variables selected in the study, obtaining biodegradation values between 3 and 80%. The percentage of biodegradation for the biosurfactant was calculated based on the increase in the surface tension of samples of the crude extract. Furthermore, it was also possible to predict the variation in t1/2 for the biosurfactant (time to achieve the 50% of biodegradation) under different conditions. 相似文献
85.
Andreev B. V. Ustinov A. S. Akopyan A. V. Anisimov A. V. Eseva E. A. Kleimenov A. V. Kondrashev D. O. Khrapov D. V. Esipenko R. V. 《Theoretical Foundations of Chemical Engineering》2020,54(5):1078-1082
Theoretical Foundations of Chemical Engineering - A technology for the demercaptanization of light hydrocarbon fractions and liquefied petroleum gas with 25% aqueous ammonia is proposed. One... 相似文献
86.
87.
The separation of iron oxide from banded hematite jasper(BHJ) assaying 47.8% Fe, 25.6% Si O2 and 2.30%Al2O3 using selective magnetic coating was studied. Characterization studies of the low grade ore indicate that besides hematite and goethite,jasper, a microcrystalline form of quartzite, is the major impurity associated with this ore. Beneficiation by conventional magnetic separation technique could yield a magnetic concentrate containing 60.8% Fe with 51% Fe recovery. In order to enhance the recovery of the iron oxide minerals, fine magnetite, colloidal magnetite and oleate colloidal magnetite were used as the coating material. When subjected to magnetic separation, the coated ore produces an iron concentrate containing 60.2% Fe with an enhanced recovery of56%. The AFM studies indicate that the coagulation of hematite particles with the oleate colloidal magnetite facilitates the higher recovery of iron particles from the low grade BHJ iron ore under appropriate conditions. 相似文献
88.
Bican Osman Bayça Salih Uğur Kuleyin Hamdi Gümrük Recep 《Metal Science and Heat Treatment》2021,63(3-4):156-162
Metal Science and Heat Treatment - The effect of solid boronizing at 950°C for 2 and 4 h on the phase composition, microstructure, hardness and abrasive wear of steel AISI 304L is studied... 相似文献
89.
Huseyin Avci Esra Akkulak Hazal Gergeroglu Hamed Ghorbanpoor Onur Uysal Ayla Eker Sariboyaci Bahar Demir Merve Nur Soykan Suat Pat Reza Mohammadigharehbagh Ceren Özel Ahmet Cabuk Fatma Doğan Güzel 《应用聚合物科学杂志》2020,137(26):49184
Among the thermoplastic elastomers that play important roles in the polymer industry due to their superior properties, styrene-based species and polyurethane block copolymers are of great interest. Poly(styrene-ethylene-butadiene-styrene) (SEBS) as a triblock copolymer seems to have the potential to meet many demands in different applications due to various industrial requirements where durability, biocompatibility, breaking elongation, and interfacial adhesion are important. In this study, the SEBS triblock copolymer was functionalized with natural (Satureja hortensis, SH) and synthetic (nanopowder, TiO2) agents to obtain composite nanofibers by electrospinning and electrospraying methods for use in biomedical and water filtration applications. The results were compared with thermoplastic polyurethane (TPU) composite nanofibers, which are commonly used in these fields. Here, functionalized SEBS nanofibers exhibited antibacterial effect while at the same time improving cell viability. In addition, because of successful water filtration by using the SEBS composite nanofibers, the material may have a good potential to be used comparably to TPU for the application. 相似文献
90.
Dr. Blijke S. Kroezen Gabriele Conti Benedetta Girardi Dr. Jonathan Cramer Dr. Xiaohua Jiang Dr. Said Rabbani Jennifer Müller Maja Kokot Enrico Luisoni Prof. Daniel Ricklin Dr. Oliver Schwardt Prof. Beat Ernst 《ChemMedChem》2020,15(18):1706-1719
Siglecs are members of the immunoglobulin gene family containing sialic acid binding N-terminal domains. Among them, Siglec-8 is expressed on various cell types of the immune system such as eosinophils, mast cells and weakly on basophils. Cross-linking of Siglec-8 with monoclonal antibodies triggers apoptosis in eosinophils and inhibits degranulation of mast cells, making Siglec-8 a promising target for the treatment of eosinophil- and mast cell-associated diseases such as asthma. The tetrasaccharide 6’-sulfo-sialyl Lewisx has been identified as a specific Siglec-8 ligand in glycan array screening. Here, we describe an extended study enlightening the pharmacophores of 6’-sulfo-sialyl Lewisx and the successful development of a high-affinity mimetic. Retaining the neuraminic acid core, the introduction of a carbocyclic mimetic of the Gal moiety and a sulfonamide substituent in the 9-position gave a 20-fold improved binding affinity. Finally, the residence time, which usually is the Achilles tendon of carbohydrate/lectin interactions, could be improved. 相似文献