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221.
222.
Isabel Domínguez Eleazar Cuautle Rafael Díaz Guy Pai? Andreas Morsch 《Indian Journal of Physics》2011,85(1):21-25
The energy loss of partons leaving the hot media created in the heavy ion collisions has been at the center of the interest
of the experimental and theoretical communities of the field. Hence an increase in the transverse momentum imbalance and acoplanarity
of dijets may be a way to study the parton energy loss. In order to study the effect, we have made simulations of dijet events
where the intrinsic k
T
of the partons, the initial and final state radiation are taken into account. The results of these simulations for p + p and Pb + Pb collisions, as a function of the center of mass energy of collision will be presented. 相似文献
223.
Antonio Doménech-Carbó María Teresa Doménech-Carbó María Amparo Peiró-Ronda Isabel Martínez-Lázaro Joaquín Barrio-Martín 《Journal of Solid State Electrochemistry》2012,16(7):2349-2356
The application of the voltammetry of microparticles methodology to date archaeological lead artifacts, based on the time-dependent formation of different layers of lead oxides, whose relative amount can be estimated from polarization curves and electrochemical impedance spectroscopy (EIS), is presented. This approach is complemented by additional data using square wave voltammetry data. Calibration of the method was performed with the help of a series of well-documented, lead pieces from the funds of different Spanish museums, covering since the 7th century BC to nowadays. 相似文献
224.
It is possible to view the relations between mathematics and natural language from different aspects. This relation between mathematics and language is not based on just one aspect. In this article, the authors address the role of the Subject facing Reality through language. Perception is defined and a mathematical theory of the perceptual field is proposed. The distinction between purely expressive language and purely informative language is considered false, because the subject is expressed in the communication of a message, and conversely, in purely expressive language, as in an exclamation, there is some information. To study the relation between language and reality, the function of ostensibility is defined and propositions are divided into ostensives and estimatives. © 2013 Wiley Periodicals, Inc. Complexity 20: 27–37, 2014 相似文献
225.
Reinaldo S. Compagnone Alírica I. Suárez Jorge L. Zambrano Ivette C. Piña José N. Domínguez 《合成通讯》2013,43(9):1631-1641
A short and versatile synthesis of a series of 3-substituted -2-aminoquinolines was accomplished in good yields starting from 2-nitrobenzaldehide. Organic phosphonates were used as key synthetic intermediates and in some cases aminoacids as readily available starting materials. The finals two key steps of the sequence involving a reduction and ring closure that led to the 2-aminoquinoline skeleton were carried out in a “one pot” procedure using SnCl2.2H2O. 相似文献
226.
Noelia Rodríguez-Pazo Laura Vázquez-Araújo Noelia Pérez-Rodríguez Sandra Cortés-Diéguez José Manuel Domínguez 《Applied biochemistry and biotechnology》2013,171(4):1042-1060
Cheese whey hydrolyzates supplemented with phenylpyruvic acid (PPA) and commercial nutrients can be efficiently metabolized by Lactobacillus plantarum CECT-221 to biosynthesize some compounds with attractive applications in the food market. The main metabolites of cell-free extracts were antimicrobial compounds such as phenyllactic acid (PLA) and lactic acid (LA). The production of PLA by L. plantarum CECT-221 was evaluated in the Man–Rogosa–Sharpe broth supplemented with two biosynthetic precursors: phenylalanine or PPA. Using 30.5 mM PPA, the microorganism increased sevenfold the concentration of PLA producing 16.4 mM PLA in 46 h. A concentration of 40 mM PPA was a threshold to avoid substrate inhibition. The biosynthesis of whey hydrolyzates as a carbon source was enhanced by fed-batch fermentation of PPA; the average productivity of PLA increased up to 45.4?±?3.02 mM after 120 h with a product yield of 0.244 mM mM?1; meanwhile, LA reached 26.1?±?1.3 g L?1 with a product yield of 0.72 g g?1. Cell-free fed-batch extracts charged in wells showed bacteriocin activity with halos of 7.49?±?1.44 mm in plates inoculated with Carnobacterium piscicola and antimicrobial activity against Staphylococcus aureus (11.54?±?1.14 mm), Pseudomonas aeruginosa (10.17?±?2.46 mm), Listeria monocytogenes (7.75?±?1.31 mm), and Salmonella enterica (3.60?±?1.52 mm). Additionally, the analysis of the volatile composition of the headspace of this cell-free extract revealed that L. plantarum is a potential producer for natural aromas, such as acetophenone, with high price in the market. This is the first report of PLA production from cheese whey and PPA. The extracts showed bacteriocin activity and potential to be applied as an antimicrobial in the elaboration of safer foods. 相似文献
227.
Biotechnological Production of Phenyllactic Acid and Biosurfactants from Trimming Vine Shoot Hydrolyzates by Microbial Coculture Fermentation 总被引:1,自引:0,他引:1
Noelia Rodríguez-Pazo José Manuel Salgado Sandra Cortés-Diéguez José Manuel Domínguez 《Applied biochemistry and biotechnology》2013,169(7):2175-2188
Coculture fermentations show advantages for producing food additives from agroindustrial wastes, considering that different specified microbial strains are combined to improve the consumption of mixed sugars obtained by hydrolysis. This technology dovetails with both the growing interest of consumers towards the use of natural food additives and with stricter legislations and concern in developed countries towards the management of wastes. The use of this technology allows valorization of both cellulosic and hemicellulosic fractions of trimming vine shoots for the production of lactic acid (LA), phenyllactic acid (PLA), and biosurfactants (BS). This work compares the study of the potential of hemicellulosic and cellulosic fractions of trimming vine shoots as cheaper and renewable carbon sources for PLA and BS production by independent or coculture fermentations. The highest LA and PLA concentrations, 43.0 g/L and 1.58 mM, respectively, were obtained after 144 h during the fermentation of hemicellulosic sugars and simultaneous saccharification and fermentation (SSF) carried out by cocultures of Lactobacillus plantarum and Lactobacillus pentosus. Additionally, cell-bond BS decreased the surface tension (ST) in 17.2 U; meanwhile, cell-free supernatants (CFS) showed antimicrobial activity against Salmonella enterica and Listeria monocytogenes with inhibition halos of 12.1?±?0.6 mm and 11.5?±?0.9 mm, respectively. 相似文献
228.
Dr. Cristina Domínguez Dr. Benoît Heinrich Dr. Bertrand Donnio Prof. Dr. Silverio Coco Prof. Dr. Pablo Espinet 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(19):5988-5995
Supramolecular mono‐ and dinuclear liquid‐crystalline gold(I) aggregates have been synthesized by means of hydrogen bond interactions of 2,4,6‐triarylamino‐1,3,5‐triazine with thiolate moities of gold metalloacids [Au(PR3)(SC6H4COOH)] or [μ‐(binap){Au(SC6H4COOH)}2], in 1:1 and 2:1 molar ratio, respectively. All of the supramolecular aggregates display a stable columnar hexagonal mesophase (Colh) at room‐temperature. The supramolecular arrangement within the columns consists of the one‐dimensional stacking of triazine units, with the core of the attached metallic thioacid fragments acting as the fourth branch. The phosphine‐containing moieties of the metallic thioacid protrude out in the aliphatic continuum. These complexes do not show metallophilic interactions, but this strategy appears very promising for the future design of room‐temperature LC mesophases containing interacting metallic fragments. 相似文献
229.
N. Pérez-Rodríguez F. Oliveira B. Pérez-Bibbins I. Belo A. Torrado Agrasar J. M. Domínguez 《Applied biochemistry and biotechnology》2014,173(3):803-825
Five microorganisms, namely Aspergillus niger CECT 2700, A. niger CECT 2915, A. niger CECT 2088, Aspergillus terreus CECT 2808, and Rhizopus stolonifer CECT 2344, were grown on corncob to produce cell wall polysaccharide-degrading enzymes, mainly xylanases, by solid-state fermentation (SSF). A. niger CECT 2700 produced the highest amount of xylanases of 504?±?7 U/g dry corncob (dcc) after 3 days of fermentation. The optimization of the culture broth (5.0 g/L NaNO3, 1.3 g/L (NH4)2SO4, 4.5 g/L KH2PO4, and 3 g/L yeast extract) and operational conditions (5 g of bed loading, using an initial substrate to moistening medium of 1:3.6 (w/v)) allowed increasing the predicted maximal xylanase activity up to 2,452.7 U/g dcc. However, different pretreatments of materials, including destarching, autoclaving, microwave, and alkaline treatments, were detrimental. Finally, the process was successfully established in a laboratory-scale horizontal tube bioreactor, achieving the highest xylanase activity (2,926 U/g dcc) at a flow rate of 0.2 L/min. The result showed an overall 5.8-fold increase in xylanase activity after optimization of culture media, operational conditions, and scale-up. 相似文献
230.
Samuel Domínguez-Hernández David J. Fernández C. 《International Journal of Theoretical Physics》2011,50(7):1993-2001
A set of supersymmetric partners of the Rosen–Morse potential is generated. The corresponding physical properties are studied—in
particular, the change in intensity of the singularities at the boundaries of the domain. 相似文献