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61.
Abdallah M. Altass H. M. El-Sayed R. Al Gorair Arej S. Jahdaly B. A. AL Sobhi M. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(4):811-819
Protection of Metals and Physical Chemistry of Surfaces - Three nonionic surfactants molecules (NS) derived from a fused pyridine characterized by IR and 1HNMR spectra were synthesized and examined... 相似文献
62.
Rafael Salomão Mirian A. Kawamura Ana B.V. Emilio José Sakihama Ana M. Segadães 《Ceramics International》2021,47(11):15082-15093
Calcium hexaluminate (CA6) is an intrinsically densification-resistant material, therefore, its porous structures are key materials for applications as high-temperature thermal insulators. This article reports on the combination of calcined alumina and calcium aluminate cement (CAC) in castable aqueous suspensions for the in situ production of porous CA6. The CAC content (10–34 vol%) and the curing conditions ensure structural integrity prior to sintering and maximize the development of hydrated phases. Changes in physical properties, crystalline phases, and microstructure were investigated after isothermal treatments (120–1500 °C), and three sequential porogenic events were observed. The hydration of CAC preserved the water-derived pores (up to 120 °C), and the dehydroxylation of CAC hydrates (250–700 °C) generated inter-particles pores. Moreover, the in situ expansive formation of CA2 and CA6 (900–1500 °C) hindered densification and generated intra-particle pores. Such events differed from those observed with other CaO sources, and resulted in significantly higher pores content and lower thermal conductivity. 相似文献
63.
Grischenko D. N. Papynov E. K. Medkov M. A. 《Theoretical Foundations of Chemical Engineering》2021,55(5):1002-1009
Theoretical Foundations of Chemical Engineering - The paper focuses on synthesis of bioactive glass with tailored properties achieved by doping it with oxides of different elements. The bioglass... 相似文献
64.
Svetlana A. Murzina Polina Yu. Dgebuadze Svetlana N. Pekkoeva Viktor P. Voronin Elena S. Mekhova Nguyen T. H. Thanh 《European Journal of Lipid Science and Technology》2021,123(7):2000321
The sea urchin Diadema setosum is edible and desirable as food by locals in central Vietnam and a promising target for potential fishing. The lipid profiles of the gonads of the sea urchin inhabiting the coastal area in Nha Trang Bay are studied for the first time. The determination of the content of the total lipids (TL), total phospholipids (PL), monoacylglycerols (MAG), diacylglycerols (DAG), triacylglycerols (TAG), cholesterol (Chol), sterol esters, and free fatty acids (FFA) is analyzed by high-performance thin layer chromatography (HPTLC); the phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and sphingomyelin (SM) are determined by high-pressure liquid chromatography (HPLC); and the fatty acid levels of TLs are identified using gas chromatography (GC). Non-polar TAG, FFA, Chol, and DAG dominated. The content of total PL is significant. PC is abundant among PL fractions, followed by PE, PI, and PS. The TLs contain a high proportion of PUFA, mainly due to arachidonic fatty acid and eicosapentanoic fatty acid. The (n−6)/(n−3) ratio is 1.68, and the atherogenic and thrombogenic indexes of D. setosum are 1.13 and 0.73. The results can be used in the development of marine bioprospecting and methodological approaches for the creation of functional substances. 相似文献
65.
Jacky Lu Kathryn P. Haley Jamisha D. Francis Miriam A. Guevara Ryan S. Doster Kelly M. Craft Rebecca E. Moore Schuyler A. Chambers Alberto G. Delgado Maria Blanca Piazuelo Steven M. Damo Dr. Steven D. Townsend Dr. Jennifer A. Gaddy 《Chembiochem : a European journal of chemical biology》2021,22(18):2783-2790
Chronic infection with Helicobacter pylori increases risk of gastric diseases including gastric cancer. Despite development of a robust immune response, H. pylori persists in the gastric niche. Progression of gastric inflammation to serious disease outcomes is associated with infection with H. pylori strains which encode the cag Type IV Secretion System (cag T4SS). The cag T4SS is responsible for translocating the oncogenic protein CagA into host cells and inducing pro-inflammatory and carcinogenic signaling cascades. Our previous work demonstrated that nutrient iron modulates the activity of the T4SS and biogenesis of T4SS pili. In response to H. pylori infection, the host produces a variety of antimicrobial molecules, including the iron-binding glycoprotein, lactoferrin. Our work shows that apo-lactoferrin exerts antimicrobial activity against H. pylori under iron-limited conditions, while holo-lactoferrin enhances bacterial growth. Culturing H. pylori in the presence of holo-lactoferrin prior to co-culture with gastric epithelial cells, results in repression of the cag T4SS activity. Concomitantly, a decrease in biogenesis of cag T4SS pili at the host-pathogen interface was observed under these culture conditions by high-resolution electron microscopy analyses. Taken together, these results indicate that acquisition of alternate sources of nutrient iron plays a role in regulating the pro-inflammatory activity of a bacterial secretion system and present novel therapeutic targets for the treatment of H. pylori-related disease. 相似文献
66.
Abulyazied Dalia E. Alturki Asma M. Youness Rasha A. Abomostafa H. M. 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(10):4077-4092
Journal of Inorganic and Organometallic Polymers and Materials - In this work, a borosilicate glass sample (5SiO2–45B2O3–20Na2O–25CaO–5Ag2O) was added to nano-sized... 相似文献
67.
Kuznetsov Yu. A. Markov M. A. Kravchenko I. N. Krasikov A. V. Bykova A. D. 《Refractories and Industrial Ceramics》2021,62(4):421-425
Refractories and Industrial Ceramics - The paper introduces a promising technology for utilizing a traditional scheme for implementing a flow-through micro-arc oxidation method to restore localized... 相似文献
68.
Ioanna Mela Chetan Poudel Miguel Anaya Géraud Delport Kyle Frohna Stuart Macpherson Tiarnan A. S. Doherty Anna Scheeder Samuel D. Stranks Clemens F. Kaminski 《Advanced functional materials》2021,31(23):2100293
Halide perovskites are a versatile class of semiconductors employed for high performance emerging optoelectronic devices, including flexoelectric systems, yet the influence of their ionic nature on their mechanical behavior is still to be understood. Here, a combination of atomic-force, optical, and compositional X-ray microscopy techniques is employed to shed light on the mechanical properties of halide perovskite films at the nanoscale. Mechanical domains within and between morphological grains, enclosed by mechanical boundaries of higher Young's Modulus (YM) than the bulk parent material, are revealed. These mechanical boundaries are associated with the presence of bromide-rich clusters as visualized by nano-X-ray fluorescence mapping. Stiffer regions are specifically selectively modified upon light soaking the sample, resulting in an overall homogenization of the mechanical properties toward the bulk YM. This behavior is attributed to light-induced ion migration processes that homogenize the local chemical distribution, which is accompanied by photobrightening of the photoluminescence within the same region. This work highlights critical links between mechanical, chemical, and optoelectronic characteristics in this family of perovskites, and demonstrates the potential of combinational imaging studies to understand and design halide perovskite films for emerging applications such as photoflexoelectricity. 相似文献
69.
R. Paxton Thedford Peter A. Beaucage Ethan M. Susca Corson A. Chao Katja C. Nowack Robert B. Van Dover Sol M. Gruner Ulrich Wiesner 《Advanced functional materials》2021,31(23):2100469
Mesoscale order can lead to emergent properties including phononic bandgaps or topologically protected states. Block copolymers offer a route to mesoscale periodic architectures, but their use as structure directing agents for metallic materials has not been fully realized. A versatile approach to mesostructured metals via bulk block copolymer self-assembly derived ceramic templates, is demonstrated. Molten indium is infiltrated into mesoporous, double gyroidal silicon nitride templates under high pressure to yield bulk, 3D periodic nanocomposites as free-standing monoliths which exhibit emergent quantum-scale phenomena. Vortices are artificially introduced when double gyroidal indium metal behaves as a type II superconductor, with evidence of strong pinning centers arrayed on the order of the double gyroid lattice size. Sample behavior is reproducible over months, showing high stability. High pressure infiltration of bulk block copolymer self-assembly based ceramic templates is an enabling tool for studying high-quality metals with previously inaccessible architectures, and paves the way for the emerging field of block-copolymer derived quantum metamaterials. 相似文献
70.
Atomic Energy - The possibility and efficacy of purifying a solution of rare-earth elements after nitric-acid decomposition of loparite concentrate from thorium by means of sorption on VP-1AP... 相似文献