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101.
102.
Evelisy C. O. Nassor Raquel V. Mambrini Eduardo N. dos Santos Flávia C. C. Moura Maria Helena Araujo 《Journal of Inorganic and Organometallic Polymers and Materials》2018,28(6):2288-2296
In this work, supported ionic liquid (IL) phases catalysts were prepared based on Pd dispersed in IL phases supported on magnetic particles of nickel/molybdenum covered with carbon (NiMo/C). The magnetic support was prepared via CVD method at 800 °C. XRD analysis showed the phases of metallic nickel and molybdenum carbide. The presence of carbon in these materials was confirmed by TEM/EDS and thermogravimetric analysis (TG) analysis. Pd particles were dispersed in 1 and 2.5 wt% of the IL 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm·BF4), which were immobilized on the support surface via impregnation method. TG analysis shows a weight loss between 300 and 420 °C attributed to the BMIm·BF4, confirming the existence of IL on the support surface. The prepared materials were investigated in hydrogenations reactions of 1,5-cyclooctadiene and nitrobenzene, and the influence of IL on the activity and selectivity of these catalysts were observed. These materials have great potential for catalysis applications, because they bring together the advantages of the IL in the catalyst surface and the facility of magnetic materials separation. 相似文献
103.
Hernán Valle Raquel Palao-Suay María Rosa Aguilar Julio San Román José Becerra Bernabé Rivas Ramalinga Viswanathan Mangalaraja 《应用聚合物科学杂志》2019,136(20):47545
In this article, an improved synthesis strategy of the potent anticancer compound 4,7-dichloro-2-quinolinemethanol (QM) and its acrylate ester 4,7-dichloro-2-quinolinemethylacrylate (AQM) are described. AQM is copolymerized using free-radical polymerization with N-vinyl-2-pyrrolidone (VP) and the copolymers obtained from different molar ratios of monomers are subjected to nanoprecipitation to produce suspensions of nanoparticles (NPs) in phosphate buffered saline (PBS). The smallest and stable NPs are prepared with the AQM-VP copolymers 45:55 and 40:60 (118.9 and 128.7 nm in diameter, respectively) at 1 mg mL−1, and along with AQM and QM, are evaluated for their cytotoxic activity on MDA-MB-453 breast carcinoma cells using MTT bioassay. AQM and QM are highly cytotoxic (IC50: 19 and 41 μM, respectively); however, the NPs are not cytotoxic in the range of the assayed concentrations. These results contribute to the search for new polymeric NPs with potential application as QM delivery systems for the treatment of cancer or other diseases treatable with QM. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47545. 相似文献
104.
Alicia Galvn Raquel Fontaneda Francisco J. Faans Flix Rodríguez 《Advanced Synthesis \u0026amp; Catalysis》2016,358(11):1741-1745
The pyrrolo[3,2,1‐ij]quinoline heterocyclic core is found in the structure of a variety of compounds with interesting applications and then, new efficient and flexible strategies to construct this skeleton are required. Here, a new diastereoselective tetrafluoroboric acid (HBF4)‐catalyzed three‐component coupling reaction of 1H‐indole‐7‐carbaldehyde derivatives, anilines and electron‐rich alkenes to give pyrrolo[3,2,1‐ij]quinolines is described. The reaction involves an unusual [4+2]‐heterocyclization between an in situ formed imine and an alkene. The new catalytic method, where water is the only by‐product, is efficient, robust and flexible, and allows for multigram‐scale synthesis.
105.
106.
L. F. Pau 《野外机器人技术杂志》1990,7(3):295-308
This article proposes a behavioral control formalism to explain situations often encountered in complex sensor/data fusion (eventually decentralized) information acquisition, command and control systems, it involves making the input-output relations of each actor involved in the fusion process conditional on selected behavioral classes, with error creation and repair options. For each behavioral class, the input-output relations are modified by concurrent behavioral rules, while the class itself has visible and hidden attributes. A formalism is also given for interactions between actors. This approach allows to describe and analyze such situations as: indirect observations, ambiguous controls, hysterisis, deadlocks, initiation of attention mechanisms. Finally, the engineering use of this approach is illustrated by three concrete designs involving humans operating indoors. 相似文献
107.
Carina A. Emilio Raquel Gettar Marta I. Litter 《Journal of Applied Electrochemistry》2005,35(7-8):733-740
TiO2-heterogeneous photocatalysis of nitrilotriacetic acid (NTA) at pH 2.5 was studied to establish the kinetic regime and the
reaction mechanism. Pure Degussa P-25 and Hombikat UV100 commercial samples were compared. A Langmuirian behavior was observed
over P-25. Platinization of the Hombikat sample (0.5 wt.%) caused an important increase on the photocatalytic rate with a
change in the kinetics from zero order in the pure precursors to first order in the platinized sample. The nature of the intermediates
and their evolution with time were compared on all systems. Glycine, iminodiacetic and oxamic acids have been identified in
different proportions, together with ammonium and glycolic acid, depending on the catalyst used. The rapid depletion of NTA
was not accompanied by a corresponding total organic carbon (TOC) reduction, but 84% of TOC decrease was obtained on P25 after
24 h, a very reasonable result for refractory compounds. A detailed mechanism is proposed for the photocatalytic reaction,
suggested to be the same over the three catalysts here tested. 相似文献
108.
The authors examine 2 issues: (a) how students integrate information from multiple scientific documents to describe and explain a physical phenomenon that represents a subset of the information in the documents; and (b) the role of 2 sorts of tasks to achieve this type of integration, either writing an essay on a question requiring integration across texts or answering shorter intratext questions that require students to integrate information within a single text, while superficial and deep comprehension measurements are obtained. Undergraduate students answered 1 of the 2 types of questions, and their reading times were recorded. Half of the sample thought aloud. Results showed that the integration question increased integration and decreased the processing of isolated units of information, which enhanced deep learning, whereas no differences between the 2 sorts of tasks on memory recall were apparent. This research also provides evidence for the discrepancy between training and posttraining effects (R. A. Schmidt & R. A. Bjork, 1992). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Ignacio Fernández‐Fígares María A García Raquel Ruiz Luis A Rubio 《Journal of the science of food and agriculture》2008,88(5):870-876
BACKGROUND: Iberian pig production is linked to the use of the Mediterranean woodland, where the use of local feed resources is of paramount importance for the sustainability of the system. The aim of the present work was to explore the potential of triticale cv. Camarma as compared to barley cv. Esgueva in Iberian pig feeding by studying their respective ileal digestibilities of amino acids and carbohydrates in animals cannulated at the end of the ileum. RESULTS: Leu, Met and Tyr had (P < 0.05) greater standardised ileal digestibilities (SID) in pigs fed triticale diet. There was a trend (P = 0.07) towards greater SID of Thr in pigs fed the barley diet. The least digestible indispensable amino acids were Ile (74.6% SID) for barley and Thr (78.9% SID) for triticale. Except for β‐glucans, apparent ileal digestibilities (AIDs) of individual non‐starch polysaccharide (NSP), sugars and starch were greater in pigs fed triticale (P < 0.05). Nevertheless, total amounts of NSP digested were greater in pigs fed the barley diet (P < 0.05). CONCLUSION: Overall, triticale cv. Camarma had greater amino acid and carbohydrate AID than barley cv. Esgueva and may represent a valuable grain for Iberian pig feeding. Copyright © 2008 Society of Chemical Industry 相似文献
110.
The rate of soil erosion in pine forests (Pinus halepensis) located in the Southeast of Madrid has been estimated using dendrochronological analysis based on the change in ring-growth pattern from concentric to eccentric when the root is exposed. Using 49 roots spread across five inclined areas, it has been found that the length and direction of the hillsides, as well as their vegetation cover affect the rate of erosion, while the slope itself does not. The erosion rates found for the different areas studied vary between 3.5 and 8.8 mm year(-1), that is between 40 and 101 t ha(-1) year(-1) respectively. These values are between 2 and 3 times greater than those predicted by USLE, for which this equation underestimates soil loss for Central Spain's Mediterranean conditions. Nonetheless, both methods (using dendrochronology to determine actual soil loss and theoretical prediction with USLE) are able to establish the same significant differences among the areas studied, allowing for the comparative estimate of the severity of the area's erosion problem. 相似文献