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排序方式: 共有918条查询结果,搜索用时 265 毫秒
911.
Thomas Dippong Erika Andrea Levei Oana Cadar 《International journal of molecular sciences》2022,23(15)
The structural, morphological and magnetic properties of MFe2O4 (M = Co, Ni, Zn, Cu, Mn) type ferrites produced by thermal decomposition at 700 and 1000 °C were studied. The thermal analysis revealed that the ferrites are formed at up to 350 °C. After heat treatment at 1000 °C, single-phase ferrite nanoparticles were attained, while after heat treatment at 700 °C, the CoFe2O4 was accompanied by Co3O4 and the MnFe2O4 by α-Fe2O3. The particle size of the spherical shape in the nanoscale region was confirmed by transmission electron microscopy. The specific surface area below 0.5 m2/g suggested a non–porous structure with particle agglomeration that limits nitrogen absorption. By heat treatment at 1000 °C, superparamagnetic CoFe2O4 nanoparticles and paramagnetic NiFe2O4, MnFe2O4, CuFe2O4 and ZnFe2O4 nanoparticles were obtained. 相似文献
912.
Franco Emanuel Vasile Lis Marlene Hryczyñski Andrea Beatriz Fernandez Leandro Fabián Bustos Ana María Romero María Florencia Mazzobre 《International Journal of Dairy Technology》2023,76(1):252-260
This work aimed to evaluate the impact of buffalo milk and nondairy ingredients on sensory properties and acceptability of custards intended for children. For this, a consumer study with 100 children aged 8 to 12 was performed. Three custard models were formulated using buffalo milk and variable amounts of corn starch, sucrose and colourant/flavouring. Compositional, mechanical and chromatic properties of custards were related to sensory characteristics and overall liking scores. Obtained results allowed understanding the consumers' preferences and identifying the drivers of liking. Buffalo milk constitutes a promising raw material for the formulation of custard intended for children. 相似文献
913.
Martina Serafini Federica Mariani Andrea Fasolini Eleonora Tosi Brandi Erika Scavetta Francesco Basile Domenica Tonelli 《Advanced functional materials》2023,33(29):2300345
In this study, new nanostructured CuMgAl Layered Double Hydroxide (LDH) based materials are synthesized on a 4 cm2 sized carbonaceous gas diffusion membrane. By means of microscopic and spectroscopic techniques, the catalysts are thoroughly investigated, revealing the presence of several species within the same material. By a one-step, reproducible potentiodynamic deposition it is possible to obtain a composite with an intimate contact between a ternary CuMgAl LDH and Cu0/Cu2O species. The catalyst compositions are investigated by varying: the molar ratio between the total amount of bivalent cations and Al3+, the amount of loading, and the molar ratios among the three cations in the electrolyte. Each electrocatalyst has been evaluated based on the catalytic performances toward the electrochemical CO2 reduction to CH3COOH at −0.4 V versus reversible hydrogen electrode in liquid phase. The optimized catalyst, that is, CuMgAl 2:1:1 LDH exhibits a productivity of 2.0 mmolCH3COOH gcat−1 h−1. This result shows the beneficial effects of combining a material like the LDHs, alkaline in nature, and thus with a great affinity to CO2, with Cu0/Cu+ species, which couples the increase of carbon sources availability at the electrode with a redox mediator capable to convert CO2 into a C2 product. 相似文献
914.
Residence time distributions (RTDs) were investigated in a retention reactor (RR) and a coaxial heat exchanger (CHE) of a commercial modular micro reaction system, to improve processing time control and implement this system as a lab scale tool for thermal process development. 相似文献
915.
Dr. Matteo Lusardi Dr. Chiara Rotolo Dr. Marco Ponassi Dr. Erika Iervasi Dr. Camillo Rosano Prof. Andrea Spallarossa 《ChemMedChem》2022,17(5):e202100670
A series of highly functionalized pyrazole derivatives has been prepared by a one-pot, versatile and regioselective procedure. Pyrazoles 1 – 29 were tested in cell-based assay to assess their antiproliferative activity against a panel of tumour cells. Additionally, the cytotoxicity of prepared compounds was evaluated against normal human fibroblasts. The antiproliferative activity of the synthesized molecules emerged to be affected by the nature of the substituents of the pyrazole scaffold and derivatives 21 – 23 proved to inhibit the growth of melanoma and cervical cancer cells. Compound 23 was identified as the most active derivative and docking simulations predicted its ability to interact with estrogen receptors. 相似文献
916.
Katar na G borov Marcela Achimovi&ccaron ov Michal Heged s Vladim r Girman M ria Ka&ncaron uchov Erika Dutkov 《Frontiers of Chemical Science and Engineering》2022,16(3):433
Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ~25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2– oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se. 相似文献
917.
Ingrid Rivera-Íñiguez Karina González-Becerra Omar Ramos-Lopez Yolanda E. Peréz-Beltrán Marian S. Chagüén-Hernández Erika Martínez-López Edgar J. Mendivil 《Molecular nutrition & food research》2023,67(14):2200675
Dyslipidemias are known risk factors for chronic diseases. Precision nutrition interventions are designed according to characteristics, such as diet, phenotype, and genotype. This systematic review aims to define a panel of genetic variants associated with lipid abnormalities that could be later used in nutrigenetic intervention studies. A systematic review is conducted following the PRISMA-P. Studies published from January 2010 to December 2020 in English language and humans are included from PubMed and ScienceDirect databases. Articles that demonstrate a strong association between polymorphisms (single nucleotide variation) of genes involved in lipid metabolism and increased risk for dyslipidemia are included. A total of 3031 articles are screened, but only 51 articles fulfill the inclusion criteria. The genes included are FABP2, MTTP related to CM synthesis and secretion; LPL, LIPC involved in triglyceride hydrolysis; CETP, APOA1, LCAT, ABCA1, and APOA5 related to lipoprotein metabolism, and APOE, LDLR, SCARB1, APOC3 involved in lipid clearance. In this systematic review, genetic variants related to chylomicron synthesis, triglyceride hydrolysis, lipoprotein metabolism, and lipid clearance demonstrate a strong association with lipid abnormalities, which can be used to design precision nutrition interventions that may help to prevent and treat dyslipidemia effectively. 相似文献
918.
Dr. Yuma Shisaka Dr. Erika Sakakibara Dr. Kazuto Suzuki Dr. Joshua Kyle Stanfield Dr. Hiroki Onoda Garyo Ueda Miu Hatano Dr. Hiroshi Sugimoto Prof. Osami Shoji 《Chembiochem : a European journal of chemical biology》2022,23(14):e202200095
Tetraphenylporphyrin (TPP) is a symmetrically substituted synthetic porphyrin whose properties can be readily modified, providing it with significant advantages over naturally occurring porphyrins. Herein, we report the first example of a stable complex between a native biomolecule, the haemoprotein HasA, and TPP as well as its derivatives. The X-ray crystal structures of nine different HasA-TPP complexes were solved at high resolutions. HasA capturing TPP derivatives was also demonstrated to inhibit growth of the opportunistic pathogen Pseudomonas aeruginosa. Mutant variants of HasA binding FeTPP were shown to possess a different mode of coordination, permitting the cyclopropanation of styrene. 相似文献