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941.
942.
Biodegradable nanocomposites based on starch/polycaprolactone/compatibilizer ternary blends reinforced with natural and organo‐modified montmorillonite 下载免费PDF全文
In this article, biodegradable polymer/clay nanocomposites were prepared. The matrices used were based on blends of Polycaprolactone (PCL) and Anhydride‐Functional Polycaprolactone (PCL‐gMA) with Thermoplastic Starch (TPS). Nanocomposites films based on PCL/TPS and PCL/PCL‐g‐MA/TPS blends reinforced with 1 and 3 wt % of natural montmorillonite and two organo‐modified ones were prepared by melt intercalation followed by compression molding. The study was designed focusing on packaging applications. Grafting maleic anhydride onto PCL was efficient to improve PCL/TPS compatibility but did not modify matrix/nanoclay interaction. Matrix compatibilization and nanoclays increased the Youn?s modulus and slightly decreased the maximum stress of the TPS/PCL matrix. Nanoclay functionalization improved nanoclay dispersion in the blends but it was not reflected in mechanical properties improvements. The water adsorption of the compatibilized matrix was reduced after clay incorporation. A slight decrease in the biodegradation rate was observed with the addition of nanoclay. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44163. 相似文献
943.
The goal of this work was to analyze the effect of different treatments on functional properties (Color parameters, water holding capacity, oil holding capacity, water imbibition capacity, protein solubility and apparent viscosity) and microstructure of three cowpea varieties. Proteins present in flours obtained from heat-treated seeds exhibited a significant increase in water and oil absorption values, water imbibition capacity, and apparent viscosity, whereas solubility decreased. Color determinations on flours showed a reduction in L* and H*, and an increment in C* with treatment intensity. Structural changes in seeds would explain the variations in the functionality of flours. This study shows that cooking and autoclaving affect significantly the functional properties of flours, while soaking had a lower impact. The knowledge about these changes will be very useful for developing and obtaining new preparations based on cowpea flour. 相似文献
944.
Paloma Abad Francisco J. Lara Natalia Arroyo-Manzanares Alberto Baños Enrique Guillamón Ana M. García-Campaña 《Food Analytical Methods》2015,8(4):916-921
A new simple analytical method for monitoring propyl propane thiosulfonate (PTSO) in animal feed is presented. PTSO is an active ingredient from Allium spp. (like onion and shallot), proposed as a natural additive for feed being an efficient alternative to antibiotics used as growth promoter due to its efficiency improving animal health. Reversed-phase liquid chromatography with UV detection has been used and a previous sample treatment based on solid-liquid extraction has been developed and optimized in order to extract PTSO from a feed for laying hens using acetone as extraction solvent. The method has been characterized obtaining limits of detection and quantification of 11.2 and 37.3 mg kg?1, respectively, which are lower than the concentrations expected in samples containing this additive. The intra- and interday relative standard deviations (RSDs) were lower than 8.3 % in all the cases, and recoveries varied from 90.2 to 94.6 %. Finally, in order to check the unequivocal identification of PTSO, mass spectrometry detection was applied. The proposed method is a simple procedure for monitoring PTSO in commercial feed, being possible to implement it in routine laboratories for quantification purposes and stability studies of the distributed products. 相似文献
945.
Unai De La Torre Beñat Pereda-Ayo Manuel Romero-Sáez Asier Aranzabal M. Pilar González-Marcos José A. González-Marcos Juan R. González-Velasco 《Topics in Catalysis》2013,56(1-8):215-221
The NOx NH3-SCR performance of several Cu and Fe catalysts supported on BETA and ZSM-5 zeolites has been studied in single SCR and double NSR–SCR configuration, and the activity related to the nature and reducibility of metal species on the catalyst surface. Intermediate ammonia formed in NSR improved greatly NOx conversion at the exit of the double NSR–SCR configuration, which was practically totally converted to N2. 相似文献
946.
Zhenqi Shi James Hermiller Salvador García Muñoz 《American Institute of Chemical Engineers》2019,65(1):87-98
The Extended Iterative Optimization Technology (EIOT) method is proposed as an extension to Muteki's [I&ECR 2013;52(35):12258–12268] Iterative Optimization Technology to address deviations from Beer–Lambert's law in powders. The new method estimates the apparent spectrum for the pure species, rather than using the measured spectrum and augments Beer–Lambert's law with a bilinear term to capture the signature and strength of the nonchemical interferences. The proposed method has exhibited acceptable performance in spite of using a lean data set to estimate its parameters. The method provides robust and coherent estimates within the physical boundaries of the system and exhibits robustness to instrument transfer. The lean effort needed to build the EIOT method positions it as an attractive option in early stages of pharmaceutical drug product development. Its robustness to distinguish chemical from nonchemical signals implies a potential to lower the total cost of ownership for an EIOT-based solution in manufacturing. © 2018 American Institute of Chemical Engineers AIChE J, 65: 87–98, 2019 相似文献
947.
V. Salgueiriño‐Maceira M. A. Correa‐Duarte 《Advanced materials (Deerfield Beach, Fla.)》2007,19(23):4131-4144
This Review article ponders core/shell structured nanoparticles that can be prepared with features that combine properties of different materials, including ligands that enhance their biocompatibility. These nanocomposites are not classified in terms of synthesis, but rather by how these features are distributed in the final morphology, attending to connected or isolated materials that end up in interacting or not‐interacting functionalities. In particular, we have focused on magnetic core/shell‐structured particles with a directly connected, coupled, or isolated second functionality. The current progress on methods in colloidal solution that have allowed the great development of these multifunctional magnetic and active spheres on biological and biomedical fields is reported. 相似文献
948.
949.
950.
We report image blurring and energy broadening effects in energy-filtered XPEEM when illuminating the specimen with soft X-rays at high flux densities. With a flux of 2×1013 photons/s, the lateral resolution in XPEEM imaging with either core level or secondary electrons is degraded to more than 50 nm. Fermi level broadening up to several hundred meV and spectral shift to higher kinetic energies are also systematically observed. Simple considerations suggest that these artifacts result from Boersch and Loeffler effects, and that the electron-electron interactions are strongest in the initial part of the microscope optical path. Implications for aberration corrected instruments are discussed. 相似文献