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141.
142.
Robson Miranda da Gama Tatiana Santana Balogh Simone França Tânia Cristina Sá Dias Valcinir Bedin André Rolim Baby Jivaldo do Rosário Matos Maria Valéria Robles Velasco 《Journal of Thermal Analysis and Calorimetry》2011,106(2):399-405
This research aimed the effect on Caucasian hair tresses treated with oxidative hair dye, either incorporated or not with
conditioners agents, analyzed by Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TG). The formulations
of hair dyes were emulsions oil-in-water with light blond color containing or not the conditioners agents: silanetriol and
panthenol; PEG-12 dimethicone; hydrolyzed silk, hydrolyzed milk protein, and lactose. Each dye (1.5 g) was applied in the
hair tress (2.0 g/20.0 cm of length of Caucasian light-brown), previously treated, more 1.5 g of hydrogen peroxide 20 vol
during 40 min. Evaluation of mass loss of the different hair sample demonstrates that these chemical hair treatments impair
the hair fibers, reduced their moisture content with respect to the untreated hair. The incorporation of conditioners agents
(silanetriol and panthenol; PEG-12 dimethicone; hydrolyzed silk, hydrolyzed milk protein, and lactose) in oxidative hair dyes
types did not decrease the damage caused on the tresses by the coloring process quantified by TG/DTG. However, the DSC curves
demonstrated those conditioners agents (silanetriol and panthenol; PEG-12 dimethicone) dislocated the beginning of the third
event in 20 °C and they inhibited the presence of the fourth event, having characterized thermal protection to the hair. 相似文献
143.
Characterization of high heating rate chars of biomass fuels 总被引:1,自引:0,他引:1
Data on biomass chars obtained under conditions similar to those of practical applications (high heating rate and low residence time) are required for co-combustion and gasification plants. A methodological procedure is developed and applied to two biomass fuels (cacao shells and olive cake) for producing high heating rate chars and characterizing their reactivity and morphology after the first steps of devolatilization. Different chars are produced in a drop tube reactor (rapid pyrolysis) by varying the nominal temperature and the residence time. Oxidation in air is performed to compare typical temperatures and kinetic parameters and evaluate the effect of the operating conditions on char reactivity. A detailed SEM analysis allows to assess the structural variations during the pyrolysis and detect the main phenomena (softening, swelling, melting, formation of bubbles). A quantitative morphological study is also performed to provide size and shape (important for biomasses) distributions of the parent fuel and the chars. These data are more significant than average values in advanced model to correctly simulate the fluid dynamic behaviour of each dimensional class of particles in large scale furnaces and gasifiers and predict a more reliable residence time of the particles. 相似文献
144.
145.
Stopping criteria for inner iterations in inexact potential reduction methods: a computational study
S. Cafieri M. D’Apuzzo V. De Simone D. di Serafino 《Computational Optimization and Applications》2007,36(2-3):165-193
We focus on the use of adaptive stopping criteria in iterative methods for KKT systems that arise in Potential Reduction methods
for quadratic programming. The aim of these criteria is to relate the accuracy in the solution of the KKT system to the quality
of the current iterate, to get computational efficiency. We analyze a stopping criterion deriving from the convergence theory
of inexact Potential Reduction methods and investigate the possibility of relaxing it in order to reduce as much as possible
the overall computational cost. We also devise computational strategies to face a possible slowdown of convergence when an
insufficient accuracy is required. 相似文献
146.
147.
148.
Selective reagent ionisation‐time of flight‐mass spectrometry: a rapid technology for the novel analysis of blends of new psychoactive substances
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Matteo Lanza W. Joe Acton Philipp Sulzer Kostiantyn Breiev Simone Jürschik Alfons Jordan Eugen Hartungen Gernot Hanel Lukas Märk Tilmann D. Märk Chris A. Mayhew 《Journal of mass spectrometry : JMS》2015,50(2):427-431
In this study we demonstrate the potential of selective reagent ionisation‐time of flight‐mass spectrometry for the rapid and selective identification of a popular new psychoactive substance blend called ‘synthacaine’, a mixture that is supposed to imitate the sensory and intoxicating effects of cocaine. Reactions with H3O+ result in protonated parent molecules which can be tentatively assigned to benzocaine and methiopropamine. However, by comparing the product ion branching ratios obtained at two reduced electric field values (90 and 170 Td) for two reagent ions (H3O+ and NO+) to those of the pure chemicals, we show that identification is possible with a much higher level of confidence then when relying solely on the m/z of protonated parent molecules. A rapid and highly selective analytical identification of the constituents of a recreational drug is particularly crucial to medical personnel for the prompt medical treatment of overdoses, toxic effects or allergic reactions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
149.
Multitarget Drug Discovery for Alzheimer's Disease: Triazinones as BACE‐1 and GSK‐3β Inhibitors
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Federica Prati Dr. Angela De Simone Dr. Paola Bisignano Dr. Andrea Armirotti Dr. Maria Summa Dr. Daniela Pizzirani Dr. Rita Scarpelli Dr. Daniel I. Perez Prof. Dr. Vincenza Andrisano Dr. Ana Perez‐Castillo Prof. Dr. Barbara Monti Francesca Massenzio Dr. Letizia Polito Prof. Dr. Marco Racchi Dr. Angelo D. Favia Dr. Giovanni Bottegoni Prof. Dr. Ana Martinez Prof. Dr. Maria Laura Bolognesi Prof. Dr. Andrea Cavalli 《Angewandte Chemie (International ed. in English)》2015,54(5):1578-1582
Cumulative evidence strongly supports that the amyloid and tau hypotheses are not mutually exclusive, but concomitantly contribute to neurodegeneration in Alzheimer′s disease (AD). Thus, the development of multitarget drugs which are involved in both pathways might represent a promising therapeutic strategy. Accordingly, reported here in is the discovery of 6‐amino‐4‐phenyl‐3,4‐dihydro‐1,3,5‐triazin‐2(1H)‐ones as the first class of molecules able to simultaneously modulate BACE‐1 and GSK‐3β. Notably, one triazinone showed well‐balanced in vitro potencies against the two enzymes (IC50 of (18.03±0.01) μM and (14.67±0.78) μM for BACE‐1 and GSK‐3β, respectively). In cell‐based assays, it displayed effective neuroprotective and neurogenic activities and no neurotoxicity. It also showed good brain permeability in a preliminary pharmacokinetic assessment in mice. Overall, triazinones might represent a promising starting point towards high quality lead compounds with an AD‐modifying potential. 相似文献
150.
Dialkyl phosphates determination by gas chromatography: Evaluation of a microwave‐assisted derivatization†
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Alessandra Cristina Pupin Silvrio Simone Caetani Machado Vanessa Bergamin Boralli Isarita Martins 《Journal of separation science》2015,38(15):2664-2669
Dialkyl phosphates are organophosphate insecticide metabolites and their urinary analysis is useful for assessing human exposure to these compounds. This study presents a sample preparation method with microwave‐assisted derivatization for two dialkyl phosphates to make the process faster before gas chromatographic analysis. The optimized conditions for derivatization procedure were: 250 μL of 2,3,4,5,6‐pentafluorobenzyl bromide 3% in acetonitrile for derivative; microwave for 5 min with intensity of 160 W. The electron ionization mass spectrometric analysis was performed using a gas chromatography with mass spectrometry QP‐2010 from the Shimadzu® equipped with RTx®‐5MS capillary column. Ions were monitored at selected‐ion monitoring mode at m/z 350 for diethyl thiophosphate and m/z 366 for diethyl dithiophosphate. The developed method was linear for both metabolites. The intra‐assay precision was the values ranged between 1.1 and 9.1%, for diethyl thiophosphate, and between 4.06 and 6.9%, for diethyl dithiophosphate. The interassay precision showed relative standard deviation between 10.3 and 15.1%, for diethyl thiophosphate and between 4.9 and 11.9%, for diethyl dithiophosphate. The results obtained suggests that derivatization assisted by microwave, before gas chromatography with mass spectrometry analysis, can be applied to monitoring of exposure to organophosphates once is fast, sensible, and precise method to determinate dialkyl phosphates. 相似文献