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排序方式: 共有926条查询结果,搜索用时 16 毫秒
121.
García-Alcaraz Jorge Luis Montalvo Francisco Javier Flor Avelar-Sosa Liliana Pérez de la Parte María Mercedes Blanco-Fernández Julio Jiménez-Macías Emilio 《Wireless Networks》2020,26(8):5713-5726
Wireless Networks - This paper presents a structural equation model that relates knowledge coordination with access to information in the process of implementing Six Sigma and their impact on the... 相似文献
122.
Francisco García-Lillo Enrique Claver-Cortés Bartolomé Marco-Lajara Mercedes Úbeda-García 《Management International Review》2017,57(4):631-652
The present research paper shows the results of an analysis of the existing literature on one of the topics that has sparked the most interest among scholars and researchers in the fields of international management and entrepreneurship: born global firms or international new ventures. Concretely, with the aim of identifying and visualising the intellectual structure of research on this phenomenon, a total of 124 research papers whose titles contain the above terms are analysed. The methodology is mainly based on the bibliometric techniques of document citation and co-citation analyses and the analysis of social networks. 相似文献
123.
Magnetic polystyrene–palygorskite nanocomposite obtained by heterogeneous phase polymerization to apply in the treatment of oily waters 下载免费PDF全文
Antonieta Middea Luciana Spinelli Fernando Gomes de Souza Junior Reiner Neumann Thais Fernandes Fabiano Richard Leite Faulstich Otavio Gomes 《应用聚合物科学杂志》2018,135(15)
Water contaminated by oil poses challenges to the management of water resources. Magnetic nanoparticles has been issue of different potential applications including remotion oil from water. Magnetic polystyrene–palygorskite nanocomposites were prepared by a heterogeneous phase polymerization for the removal of organic contaminants from water. The organo‐Fe3O4‐palygorskite nanoparticles were coated with polystyrene, forming water repellent and oil absorbing surfaces to promote the removal of oil from the surfaces of nanocomposites by applying an external magnetic field. X‐ray fluorescence, X‐ray diffraction, scanning electron microscopy, zeta potential and size distribution measurement, surface area determination by BET, density measurement by He pycnometry, carbon grade determination, thermogravimetric analysis, Fourier‐transform infrared spectroscopy, Raman spectroscopy, and evaluation of hydrophobicity by contact angle were used to characterize the nanoparticles. The magnetic nanocomposite obtained showed excellent hydrophobicity, around 78° contact angle. In addition, oil removal capability tests were also performed, according to which the preliminary results indicated removal of approximately 98% of oil in synthetic oily water samples. The oil–water separation using this magnetic nanocomposite provides a promising alternative strategy for water treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46162. 相似文献
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The degradation of glycolic acid in aqueous media was performed by homogeneous photochemical and heterogeneous photocatalytic processes using different kinds of chemical reactors. The efficiency of the degradation processes was evaluated by measuring both the reactant conversion and the decrease of the total organic carbon (TOC) of the solution. The best results were obtained by using a continuous reactor with a fixed supported photocatalyst. 相似文献
127.
Fiorella Sinesio Corrado Di Natale Giovanni B Quaglia Francesco M Bucarelli Elisabetta Moneta Antonella Macagnano Roberto Paolesse Arnaldo DAmico 《Journal of the science of food and agriculture》2000,80(1):63-71
In this paper the performances of an electronic nose based on metalloporphyrin‐coated quartz microbalance sensors and of an experienced panel of seven human assessors in the evaluation of gases derived from degradation reactions in tomatoes are presented and discussed. The performances are measured in terms of the capability of both systems to distinguish between samples of different quality coming from conventional and organic production systems. The study deals with the application of pattern recognition techniques based on either multivariate statistical methods (PCA, GPA) or artificial neural networks using a self‐organising map (SOM). The response pattern of the sensor array and the sensory data are analysed and compared using these methods. Similarities in the classification of the data by electronic nose and human sensory profiling are found. © 2000 Society of Chemical Industry 相似文献
128.
Mercedes E. Campderrs Adolfo O. Acosta Jos Marchese 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1998,72(1):55-59
The coupled transport of copper(II) ions through a supported liquid membrane containing LIX 984 as the mobile carrier dissolved in kerosene has been studied. Many commercial membrane supports were investigated at different stirrer speeds in a permeation cell. An equation describing the permeation rate has been derived, taking into account stagnant layer aqueous diffusion and liquid membrane diffusion. By means of this treatment the copper overall transfer resistance and the experimental determination of the effective porosity factor (ε/τ), for each support have been performed. The Accurel® 2E-PP membrane showed a relatively high value of ε/τ (0·91), which makes this membrane an adequate support when the transport properties of the supported liquid membrane are concerned. © 1998 SCI 相似文献
129.
Mercedes P Geimba Alessandro Riffel Viviane Agostini Adriano Brandelli 《Journal of the science of food and agriculture》1999,79(13):1849-1854
Cellulose-hydrolysing enzymes from the phytopathogenic fungus Bipolaris sorokiniana were partially purified and characterised. The enzyme production was variable according to the carbon source. β-Glucosidase and cellobiohydrolase activities were higher by growing the fungus on cellulose than on other carbon sources. Carboxymethyl cellulase production was stimulated by other carbohydrates, mainly lactose. Partial enzyme purification was carried out by liquid chromatography on Sepharose CL4B. The purification was about 17-fold, with a yield of 41% as judged by assay with p-nitrophenyl-β-D -glucopyranoside as substrate. The optimum pH and temperature were 5.0 and 55–60 °C respectively. The enzyme was stable at 28 and 37 °C but lost about 50% of its initial activity after 120 min at 55 °C. Saccharification of cellulosic materials such as crystalline cellulose, filter paper and wheat straws was carried out using the partially purified enzyme, resulting in the production of reducing sugars. © 1999 Society of Chemical Industry 相似文献
130.
Salmonellatyphimurium inactivation at pH 3.0 in Brain Heart Infusion (BHI) and Meat Extract (ME) was studied using stationary-phase cells grown in non-acidified BHI (pH 7.4) and ME (pH 6.6) and acidified BHI and ME at pH values of 6.4, 5.4 and 4.5 with acetic, ascorbic, citric, lactic, malic and hydrochloric acids. Cells grown in buffered BHI (pH 7.0) were used as non-acid adapted control cells. 相似文献