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101.
Piero Savarino Enzo Montoneri Miriam Biasizzo Pierluigi Quagliotto Guido Viscardi Vittorio Boffa 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(10):939-948
BACKGROUND: In the context of the modern concern regarding rapid consumption and low availability of fossil sources of energy and chemicals, urban and agro‐industrial sources of chemicals represent interesting environmentally friendly alternatives. A recent paper has shown that a humic acid‐like material extracted from urban and green wastes compost exhibits very good surfactant properties. A large number of technological applications could possibly use this material as a chemical auxiliary. This paper reports on the performance of the material as a chemical auxiliary in textile dyeing. RESULTS: The compost‐isolated humic acid‐like bio‐surfactant is shown to perform in nylon 6 microfiber dyeing by water soluble and insoluble dyes as well as and more conveniently than commercial sodium dodecylsulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS). With both types of dye the bio‐surfactant allows the same quality of dyed product as the synthetic surfactants do, but at lower additive concentration. From process cost and environmental impact points of view, the bio‐surfactant has the advantages of operating at much lower additive concentrations and should be available at significantly lower cost than the synthetic surfactants. CONCLUSION: The results suggest that biomass wastes may be a low cost renewable source of chemicals with friendly environmental impact. Such a perspective implies economic and environmental benefits deriving from a new waste management technology that considers biomass waste as a source of chemicals, and from lower oil consumption in the manufacture of synthetic surfactants. Copyright © 2007 Society of Chemical Industry 相似文献
102.
103.
Hormoz Azizian Magdi M. Mossoba Ali Reza Fardin‐Kia Pierluigi Delmonte Sanjeewa R. Karunathilaka John K. G. Kramer 《Lipids》2015,50(7):705-718
A new, rapid Fourier transform near infrared (FT‐NIR) spectroscopic procedure is described to screen for the authenticity of extra virgin olive oils (EVOO) and to determine the kind and amount of an adulterant in EVOO. To screen EVOO, a partial least squares (PLS1) calibration model was developed to estimate a newly created FT‐NIR index based mainly on the relative intensities of two unique carbonyl overtone absorptions in the FT‐NIR spectra of EVOO and other mixtures attributed to volatile (5280 cm?1) and non‐volatile (5180 cm?1) components. Spectra were also used to predict the fatty acid (FA) composition of EVOO or samples spiked with an adulterant using previously developed PLS1 calibration models. Some adulterated mixtures could be identified provided the FA profile was sufficiently different from those of EVOO. To identify the type and determine the quantity of an adulterant, gravimetric mixtures were prepared by spiking EVOO with different concentrations of each adulterant. Based on FT‐NIR spectra, four PLS1 calibration models were developed for four specific groups of adulterants, each with a characteristic FA composition. Using these different PLS1 calibration models for prediction, plots of predicted vs. gravimetric concentrations of an adulterant in EVOO yielded linear regression functions with four unique sets of slopes, one for each group of adulterants. Four corresponding slope rules were defined that allowed for the determination of the nature and concentration of an adulterant in EVOO products by applying these four calibration models. The standard addition technique was used for confirmation. 相似文献
104.
Anna Maria Giannini Fabio Ferlazzo Roberto Sgalla Pierluigi Cordellieri Francesca Baralla Silvia Pepe 《Accident; analysis and prevention》2013
The aim of the study was to evaluate the use of videos in educational programs for improving road safety. Particularly, we evaluated the cognitive and emotional effects of viewing videos taken from cameras placed along Italian highways and showing car crashes or traffic flow images. 相似文献
105.
Analysis of chlorinated fatty acids (CFA) in tissues can be difficult because of their low concentrations. This task becomes
even more difficult when samples are from organisms living in remote locations with very little exposure to environmental
contamination. Therefore, enrichment of CFA is necessary prior to analysis. In this study, CFA were enriched from fractionated
lipid classes of cardiac and skeletal muscle of Chinook salmon (Oncorhynchus tshawytscha) to determine CFA distribution among lipid classes and tissue types and to demonstrate the sensitivity of this method to
detect CFA at trace concentrations. The lipids extracted from cardiac and skeletal muscle of O. tshawytscha were separated into fractions containing TAG, FFA, and phospholipids. After transesterification, the FAME derivatives from
each lipid class were analyzed by GC with a halogen-selective detector (XSD) to determine the concentrations of dichlorostearic
acid and dichloropalmitic acid. Other chlorinated compounds detected byGC-XSD were analyzed by GC-MS. CFA were observed in
all lipid classes in both cardiac and skeletal muscle tissues. However, the highest concentrations of CFA were found in the
phospholipids of both tissue types, about 1–2 mg/g lipid. It was also shown that dichloropalmitic acid concentrated in cardiac
phospholipids whereas dichlorostearic acid was found primarily in the phospholipids of skeletal tissue. CFA concentrations
in TAG and FFA fractions were below 150 mg/g lipid. This study demonstrates a small-scale approach to the study of CFA at
trace concentrations and their distribution among lipid classes. 相似文献
106.
107.
Cauchi Marija Grech Ivan Mallia Bertram Mollicone Pierluigi Portelli Barnaby Sammut Nicholas 《Microsystem Technologies》2022,28(6):1435-1450
Microsystem Technologies - Over the past years, microelectromechanical systems (MEMS) have become a vital component within a wide range of technologies, making the study of their performance and... 相似文献
108.
This paper presents an optimized equivalent consumption minimization strategy(ECMS) for four-wheel-drive(4 WD) hybrid electric vehicles(HEVs) incorporating vehicle connectivity. In order to be applicable to the 4 WD architecture, the ECMS is designed based on a rule-based strategy and used under the condition that a certain propulsion mode is activated. Assuming that a group of 4 WD HEVs are connected and position information can be shared with each other, we formulate a decentralized model predictive control(MPC) framework that compromises fuel efficiency, mobility, and inter-vehicle distance to optimize the velocity profile of each individual vehicle. Based on the optimized velocity profile, an optimization problem considering both fuel economy and battery state of charge(SOC) sustainability is formulated to optimize the equivalent factors(EFs) of the ECMS for HEVs over an appropriate time window. MATLAB User Datagram Protocol(UDP) is used in the codes run on multiple computers to simulate the wireless communication among vehicles, which share position information via UDP-based communication, and dSPACE is used as a software-in-the-loop platform for the simulation of the optimized ECMS. Simulation results validate the control effectiveness of the proposed method. 相似文献
109.
Foulquié Moreno MR Rea MC Cogan TM De Vuyst L 《International journal of food microbiology》2003,81(1):73-84
Two strains, Enterococcus faecium RZS C5 and E. faecium DPC 1146, produce listericidal bacteriocins, so-called enterocins. E. faecium RZS C5 was studied during batch fermentation in both a complex medium (MRS) and in milk to understand the influence of environmental factors, characteristic for milk and cheese, on both growth and bacteriocin production. Fermentation conditions were chosen in view of the applicability of in situ enterocin production during Cheddar cheese production. Enterocin production by E. faecium RZS C5 in MRS started in the early logarithmic growth phase, and enterocin activity decreased during the stationary phase. The effect of pH on enterocin production and decrease of activity was as intense as the effect on bacterial growth. Higher enterocin production took place at pH 5.5 compared with pH 6.5. The use of lactose instead of glucose increased the production of enterocin, and at higher lactose concentration, production increased more and loss of activity decreased. The production in skimmed milk compared to MRS was lower and was detected mainly in the stationary phase. When casein hydrolysate was added to the milk, enterocin production was higher and started earlier, indicating the importance of an additional nitrogen source for growth of E. faecium in milk. For co-cultures of E. faecium RZS C5 with the starters used during Cheddar cheese manufacture, no enterocin activity was detected during the milk fermentation. Furthermore, the applicability of E. faecium RZS C5 and E. faecium DPC 1146 strains was tested in Cheddar cheese manufacture on pilot scale. Enterocin production took place from the beginning of the cheese manufacturing and was stable during the whole ripening phase of the cheese. This indicates that both an early and late contamination of the milk or cheese can be combated with a stable, in situ enterocin production. The use of such a co-culture is an additional safety provision beyond good manufacturing practices. 相似文献
110.
Influence of carbon and nitrogen source on production of volatile fragrance and flavour metabolites by the yeast Kluyveromyces marxianus 下载免费PDF全文
Loughlin Gethins Onur Guneser Aslı Demirkol Mary C. Rea Catherine Stanton R. Paul Ross Yonca Yuceer John P. Morrissey 《Yeast (Chichester, England)》2015,32(1):67-76
The yeast Kluyveromyces marxianus produces a range of volatile molecules with applications as fragrances or flavours. The purpose of this study was to establish how nutritional conditions influence the production of these metabolites. Four strains were grown on synthetic media, using a variety of carbon and nitrogen sources and volatile metabolites analysed using gas chromatography–mass spectrometry (GC–MS). The nitrogen source had pronounced effects on metabolite production: levels of the fusel alcohols 2‐phenylethanol and isoamyl alcohol were highest when yeast extract was the nitrogen source, and ammonium had a strong repressing effect on production of 2‐phenylethyl acetate. In contrast, the nitrogen source did not affect production of isoamyl acetate or ethyl acetate, indicating that more than one alcohol acetyl transferase activity is present in K. marxianus. Production of all acetate esters was low when cells were growing on lactose (as opposed to glucose or fructose), with a lower intracellular pool of acetyl CoA being one explanation for this observation. Bioinformatic and phylogenetic analysis of the known yeast alcohol acetyl transferases ATF1 and ATF2 suggests that the ancestral protein Atf2p may not be involved in synthesis of volatile acetate esters in K. marxianus, and raises interesting questions as to what other genes encode this activity in non‐Saccharomyces yeasts. Identification of all the genes involved in ester synthesis will be important for development of the K. marxianus platform for flavour and fragrance production. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献