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961.
962.
Óscar L. Ramos Sara I. Silva José C. Soares João C. Fernandes M. Fátima Poças Manuela E. Pintado F. Xavier Malcata 《Food research international (Ottawa, Ont.)》2012,45(1):351-361
The goal of this research effort was to assess the efficacy of edible films produced from whey protein isolate (WPI) and glycerol, including incorporation of lactic acid (LA) and propionic acid (PRO), chitooligosaccharides with nominal MW of 3 kDa (COS) and natamycin (NA) as antimicrobial agents. Their features were evaluated in vitro via agar diffusion and viable cell counting, against spoilage microflora often found contaminating cheese surfaces. The effect of incorporating the aforementioned compounds upon thickness, moisture content (MC), solubility (S), density (ρs), water activity (aw) and water vapor permeability (WVP), as well as upon tensile and optical properties of those films were also evaluated. Films formulated with LA, PRO or COS exhibited antimicrobial activity against all microorganisms tested, yet the viable cell count assay was more sensitive and reproducible. COS was the most active against Gram-negative bacteria, whereas LA was the most active against Gram-positive ones. NA was not active against bacteria, but displayed the strongest effect against yeasts. Incorporation of said antimicrobial compounds did not significantly (p > 0.05) affect film thickness, yet it significantly (p < 0.05) reduced tensile strength (TS). Incorporation of LA and NA in particular did not significantly (p < 0.05) affect MC, S, ρs, WVP, elongation at break (EB) and Young's modulus (YM) values; however, a statistically significant increase (p < 0.05) of MC, S and WVP, together with a statistically significant decrease (p < 0.05) of ρs were attained upon incorporation of PRO or COS. Moreover, PRO produced the highest variation (p < 0.05) in EB, TS and YM, whereas COS produced the highest change (p < 0.05) in optical properties. 相似文献
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966.
Ramos B. Pinho D. Martins D. Vaz A. I. F. Vicente L. N. 《Optimization and Engineering》2022,23(2):1085-1116
Optimization and Engineering - Three-dimensional (3D) printing, also known as additive manufacturing (AM), has emerged in the last decades as an innovative technology to build complex structures.... 相似文献
967.
Denise Ramos Moreira Elano Nery Ferreira João Francisco Câmara Neto Lucas Lima Bezerra Norberto de Kássio Vieira Monteiro Camila Peixoto do Valle Tathilene Bezerra Mota Gomes Arruda Pedro de Lima Neto Jailson Silva Rodrigues Francisco Eduardo Arruda Rodrigues César Liberato Petzhold Martin E. Maier Nágila Maria Pontes Silva Ricardo 《Journal of the American Oil Chemists' Society》2022,99(4):341-352
Fish farming is a worldwide growing activity and a large amount of residues is produced in this process. The present work describes a cleaner and sustainable way to produce new lubricants from fish waste oil. Oil extracted from the Nile tilapia (Oreochromis niloticus) viscera was utilized as raw material to produce basic oil for lubricants. The products were synthesized by esterification with polyols, trimethylolpropane (TMP) and pentaerythritol (PE), using p-toluenesulfonic acid (p-TSA) as catalyst. The synthesized esters were characterized by infrared (IR) and nuclear magnetic resonance (NMR). Computational methods were used to predict the physical characteristics of the material. In addition, the main physicochemical properties were evaluated, as well as the thermal behavior and toxicity of the products against Artemia salina. The synthesized esters showed high viscosity indexes (VI > 150) and viscosities that fit the degree of application ISO-46 and 150. Molecular dynamics simulations indicated that at room temperature the lubricants Tilapia fatty acid - trimethylolpropane ester (T-TMPE) and Tilapia fatty acid - pentaerythritol ester (T-PEE) are in liquid and gel states, respectively, confirming the experimental data. The products did not present toxicity against A. salina. In this research, we reinforce the potential of using tilapia oil from waste to produce green lubricants as a strategy to reduce damage to the environment, as well as the use of computational methods that collaborate to predict physical properties of lubricants. 相似文献
968.
This paper looks at the relationship between remittances and higher education in Moldovan regions. The objective is to test whether remittances are associated with an increase in the likelihood of attending higher education institutions by taking into account a possible disruptive effect of migration and looking for regional differences in this relationship. Findings show that, on average, remittances are associated with a 5.4 percentage point increase in the likelihood that young individuals will pursue higher education. Nonetheless, this result is widely heterogeneous across regions. 相似文献
969.
S. Ramos de Debiaggi G.F. Cabeza C. Deluque ToroA.M. Monti S. Sommadossi A. Fernández Guillermet 《Journal of Alloys and Compounds》2011,509(7):3238-3245
The physico-chemical properties of the intermetallic phases in the Cu-In system have been a matter of considerable theoretical and experimental interest in connection with, i.a., the application of In-Sn alloys as lead-free micro-soldering alloys. Recently, a new binary compound with the chemical formula Cu10In7 has been detected in a study of the η-phase field. The structure of the Cu10In7 phase has been determined as closely related to that of the Cu11In9 compound occurring in the phase diagram, but no experimental or theoretical information on its electronic structure, thermodynamic and equation-of-state properties has yet been reported. In the present work we report the lattice parameters, bulk modulus, energy of formation from the constituent elements and the electronic structure of the new phase, calculated by applying an ab initio density-functional-theory method. Our calculation technique uses the projector augmented wave potentials and the exchange-correlation functions of Perdew and Wang in the generalized gradient approximation. The present results for the Cu10In7 phase are compared with the experimental data available, and with the trends in structural and thermodynamic properties emerging from ab initio calculations also performed in the present study for various structurally related and neighboring compounds in the Cu-In phase diagram, viz., the ideal B82-Cu2In, B81-CuIn, B82-CuIn2 phases and the Cu11In9 compound. 相似文献
970.
Deng Yuefan Guo Meng Ramos Alexandre F. Huang Xiaolong Xu Zhipeng Liu Weifeng 《The Journal of supercomputing》2020,76(12):9558-9584
The Journal of Supercomputing - We propose that clusters interconnected with network topologies having minimal mean path length will increase their processing speeds. We approach our heuristic by... 相似文献