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排序方式: 共有427条查询结果,搜索用时 15 毫秒
1.
Dr. Anders Højgaard Hansen Henriette B. Christensen Dr. Sunil K. Pandey Dr. Eugenia Sergeev Alice Valentini Julia Dunlop Domonkos Dedeo Simone Fratta Dr. Brian D. Hudson Prof. Graeme Milligan Prof. Trond Ulven Prof. Elisabeth Rexen Ulven 《ChemMedChem》2021,16(21):3326-3341
Free fatty acid receptor 2 (FFA2) is a sensor for short-chain fatty acids that has been identified as an interesting potential drug target for treatment of metabolic and inflammatory diseases. Although several ligand series are known for the receptor, there is still a need for improved compounds. One of the most potent and frequently used antagonists is the amide-substituted phenylbutanoic acid known as CATPB ( 1 ). We here report the structure-activity relationship exploration of this compound, leading to the identification of homologues with increased potency. The preferred compound 37 (TUG-1958) was found, besides improved potency, to have high solubility and favorable pharmacokinetic properties. 相似文献
2.
Automation and control system for fluid dynamic stability in hollow‐fiber membrane bioreactor for cell culture 下载免费PDF全文
3.
ABSTRACTIn the present paper, the mechanical properties and the scratch failure mechanisms of Ni–P electroless coatings are described. The material microstructure was studied in as-deposited and annealed conditions through SEM and EDS analyses. Nanoindentation measurements on the coatings showed a remarkable hardening due to the crystallization and precipitation behaviour produced by annealing. The scratch tests, conducted by increasing the load during scratch, revealed the coating failure mechanisms in a broad range of applied stresses up to delamination. 相似文献
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Amir H. Tavakoli Renzo Campostrini Christel Gervais Florence Babonneau Joachim Bill Gian D. Sorarù Alexandra Navrotsky 《Journal of the American Ceramic Society》2014,97(1):303-309
The structure and properties of polymer‐derived Si–(B–)O–C glasses have been shown to be significantly influenced by the boron content and pyrolysis temperature. This work determined the impact of these two parameters on the thermodynamic stability of these glasses. High‐temperature oxide melt solution calorimetry was performed on a series of amorphous samples, with varying boron contents (0–7.7 at.%), obtained by pyrolysis of precursors made by a sol–gel technique. Thermodynamic analysis of the calorimetric results demonstrated that at a constant pyrolysis temperature, adding boron makes the materials energetically less stable. While the B‐containing glasses pyrolyzed at 1000°C were energetically less stable than the competitive crystalline components, increasing the pyrolysis temperature to 1200°C led to their enthalpic stability. 29Si and 11B MAS nuclear magnetic resonance (NMR) spectroscopy measurements on selected samples confirmed a decrease in the concentrations of mixed Si‐centered SOiC4?i and B‐centered BOjC3?j bonds at the expense of formation of SiO4 and B(OSi)3 species (indicating a tendency toward phase separation) when the boron content and pyrolysis temperature increased. In light of the findings from calorimetry and NMR spectroscopy, we propose a structure–energetic relationship in Si–(B–)O–C glasses. 相似文献
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Camilla Costa Renzo Di Felice Paolo Moretti Maddalena Oliva Rouzbeh Ramezani 《加拿大化工杂志》2020,98(12):2516-2529
This work is a companion to a previous article, Part I, published in The Canadian Journal of Chemical Engineering, dealing with CO2 absorption in aqueous solutions containing a single aminic reagent (specifically methyldiethanolamine (MDEA) or piperazine (PZ)). In this second part, different PZ/MDEA mixtures are experimentally studied and their performances are compared with that of the single reagents. It is indeed well known that small quantities of PZ added to MDEA aqueous solutions are sufficient to obtain a significant improvement in the kinetics of the process. PZ is considered an activator or promoter for MDEA, but the mechanism of this synergy has still not been clearly demonstrated. The aim of this study is an attempt to understand how PZ and MDEA can interact by experimentally analyzing this beneficial mutual effect and by explaining it with the help of a suitable yet not complex model. We believe that the involved chemistry is not more complex than that reported in Part I for the single reagents. According to our findings, it is MDEA that enhances the action of PZ, as opposed to what many authors claim. Moreover, our results seem to rule out the existence of any PZ shuttle effect. 相似文献
8.
Evaluation of performance of various color‐difference formulae using an experimental black dataset 下载免费PDF全文
Renzo Shamey Juan Lin Weethima Sawatwarakul Renbo Cao 《Color research and application》2014,39(6):589-598
The objective of this study was to develop a specific visual dataset comprising black‐appearing samples with low lightness (L* ranging from approximately 10.4 to 19.5), varying in hue and chroma, evaluating their visual differences against a reference sample, and testing the performance of major color difference formulas currently in use as well as OSA‐UCS‐based models and more recent CAM02 color difference formulas including CAM02‐SCD and CAM02‐UCS models. The dataset comprised 50 dyed black fabric samples of similar structure, and a standard (L*= 15.33, a* = 0.14, b* = ?0.82), with a distribution of small color differences, in ΔE*ab, from 0 to approximately 5. The visual color difference between each sample and the standard was assessed by 19 observers in three separate sittings with an interval of at least 24 hours between trials using an AATCC standard gray scale for color change, and a total of 2850 assessments were obtained. A third‐degree polynomial equation was used to convert gray scale ratings to visual differences. The Standard Residual Sum of Squares index (STRESS) and Pearson's correlation coefficient (r), were used to evaluate the performance of various color difference formulae based on visual results. According to the analysis of STRESS index and correlation coefficient results CAM02 color difference equations exhibited the best agreement against visual data with statistically significant improvement over other models tested. The CIEDE2000 (1:1:1) equation also showed good performance in this region of the color space. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 589–598, 2014 相似文献
9.
Tiago Pinheiro Braga Ant?nio Narcísio Pinheiro W. T. Herrera Y. T. Xing E. Baggio-Saitovitch Antoninho Valentini 《Journal of Materials Science》2011,46(3):766-773
Iron oxide nanoparticles dispersed in aluminum (Al) or silicon (Si) oxides were prepared via a polymeric precursor derived
from the Pechini method. The samples were characterized by thermogravimetric analysis, Fourier-transform infrared spectroscopy,
X-ray diffraction, N2 adsorption/desorption isotherms (Brunauer–Emmett–Teller, BET), M?ssbauer spectroscopy, and vibrating sample magnetometry
(VSM). BET analysis shows that the samples are mesoporous materials and have a high surface area. The size of the Fe2O3 nanoparticles in Al2O3 is smaller than that in SiO2. M?ssbauer spectra of the samples show that the Fe2O3 nanoparticles in Al2O3 are non-magnetic at room temperature but magnetic below 50 K. The FeSi samples are magnetic at both room and low temperatures.
The magnetic measurements with VSM confirmed this point. 相似文献
10.
Abstract: The hole‐drilling method is one of the most used techniques for the experimental analysis of the residual stresses in mechanical components. For both through‐thickness uniform and non‐uniform residual stress distributions, its application is standardised by the ASTM E837‐08. In accordance with the ASTM limitations, the analysis of uniform residual stresses, to which the present work deals with, leads in general to results with a maximum bias of about 10%. Unfortunately, in general the user does not have appropriate procedures to estimate the actual stress error; consequently, if one or more of the experimental influence parameters fall out of the corresponding standard limitations, the computed residual stresses have to be considered as qualitative results. In order to overcome such drawbacks as well as to permit in general the estimation of the stress uncertainty, in the present work the procedures for the correction of the effects of the main error sources and for the stress uncertainty estimation, are proposed. The practical application of such procedures is carried out by using a simple calculation code properly implemented in Matlab environment. Also, the use of this tool allows the user to highlight the relative error and the stress uncertainty contribution of each influence parameter. 相似文献