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121.
J. Oliva C. Gomez-Solis J.A. Pinedo Escobar M.A. Vallejo D. Garcia de la Cruz C.R. Garcia E. Puentes-Prado 《International Journal of Hydrogen Energy》2021,46(11):7926-7938
This work reports the performance of TiO2/BiI3 and TiO2/PbI2 nanocomposites for hydrogen generation. BiI3 and PbI2 quantum dots (QDs) were grown on TiO2 (P25 Degussa) using a fast injection method. According to the analysis by X-ray diffraction, the nanocomposites have a mixture of anatase, rutile and cubic phases from TiO2, BiI3 and PbI2. The images obtained from transmission electron microscopy revealed that the TiO2 support have sizes in the range of 70–220 nm while the QDs of BiI3 and PbI2 (co-catalysts) grown on TiO2 have sizes in the range of 12–17 nm. The presence of these iodides on TiO2 created oxygen vacancies defects (confirmed by photoluminescence measurements) that extended the light absorption of TiO2 from the UV to the VIS range. According to the results from the photocatalytic experiments for hydrogen generation (achieved using pure water and UV-VIS light), the hydrogen generation rates produced by the TiO2/BiI3 and TiO2/PbI2 nanocomposites were 437–580 times, 81–108 times and 21–30 times, higher than these for pure TiO2, PbI2 and BiI3, respectively. The maximum hydrogen generation rates of the TiO2/BiI3 and TiO2/PbI2 nanocomposites were 290.7 and 219.2 μmol h?1 g?1, respectively. In addition, the TiO2/BiI3 and TiO2/PbI2 nanocomposites contained defects that acted as electron trapping centers, which in turn, delayed the electron-hole recombination and this favored the photocatalytic generation of H2. Moreover, the heterojunction formed between the TiO2 and the iodides allowed the transfer of electrons from the conduction band of TiO2 toward the conduction band of the iodides, creating a “sink” for the electrons which delayed the electron hole recombination. The results presented here demonstrated that the deposition of iodide co-catalyst on TiO2 is a feasible option to enhance the hydrogen generation. 相似文献
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Anthocyanin profile of red fruits and black carrot juices,purees and concentrates by HPLC‐DAD‐ESI/MS‐QTOF
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Patricia Garcia‐Herrera Maria‐Luisa Pérez‐Rodríguez Teresa Aguilera‐Delgado Maria‐Jose Labari‐Reyes Begoña Olmedilla‐Alonso Montana Camara Sonia de Pascual‐Teresa 《International Journal of Food Science & Technology》2016,51(10):2290-2300
A fast and reliable method for anthocyanin extraction and identification by HPLC‐DAD‐ESI/MS‐QTOF was used to analyse the anthocyanin composition of commercial red fruit juices (blackberry, redcurrant and pomegranate), purees (strawberry, cherry and raspberry) and concentrates (elderberry, blueberry and red grape). The anthocyanin profile of black carrot juice is also reported. The extraction and analysis method allowed us to detect and quantify a wide range of individual anthocyanins in a simple and rapid way. Pelargonidin‐3‐glucoside was detected in redcurrant for the first time and petunidin‐3‐galactoside quantified for the first time in blueberries. Considering the health benefits that have been associated with anthocyanin consumption, all these fruit and vegetables processed products could appear as a good source of this group of phytochemical compounds for their direct consumption or their use as ingredients for the design of new food product or food supplements. 相似文献
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Mary Ann O. Torio Takafumi Itoh Roberta N. Garcia Nobuyuki Maruyama Shigeru Utsumi Evelyn Mae Tecson-Mendoza 《Food research international (Ottawa, Ont.)》2012,45(1):277-282
Sulfhydryl groups and disulfide bond were introduced in mungbean's major storage protein, 8Sα globulin, by protein engineering to improve structural stability and functional properties. Five modified proteins or mutants (F59C, I99C, A213C, one free sulfhydryl group; I99C/A213, one disulfide bridge; F59C/I99C/A213C, one free sulfhydryl group and one disulfide linkage) were expressed in Escherichia coli at a yield similar to that of the unmodified protein or wild type (WT) in soluble form (38%). The number of introduced groups in the mutants was confirmed by Ellman analysis. Mutant and WT proteins exhibited similar elution patterns on gel filtration indicating their trimeric native conformation. Mutants had 2 to 3.8 °C higher Tm values than WT and were digested by chymotrypsin at 52–58% in 60 min but exhibited different digestion patterns. All mutants showed greater hardness of heat-induced gels than WT, especially I99C/A213C and F59C/I99C/A213C. Results indicate the improved structural stability of the modified 8Sα globulin. 相似文献
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Topological reconfiguration is an important tool for the planning and operation of electric power distribution systems. The amount of time that an algorithm spends to obtain an alternative topological status for the system is not a primary concern, as the main goals of distribution operation planning are the reduction of power losses, the enhancement of the voltage profile, and the increase of reliability levels. The utility can use multiple criteria regarding the observation of regulation policies and public awareness to drive the topological reconfiguration. Several researchers are looking for new optimization methods, as the complexity of this combinatorial issue is high in large systems and the classic optimization methods are failing to address the problem reasonably. Therefore, a new fuzzy multi-criteria decision making algorithm for the proper processing of the information sources available at the utilities in the context of distribution network reconfiguration is proposed. The algorithm is evaluated through the use of a proof-of-concept implementation in a set of case studies based on actual distribution systems. 相似文献
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Garcia Hector A.; Kelley Lance P.; Rentz Timothy O.; Lee Shuko 《Canadian Metallurgical Quarterly》2011,8(1):1
Cognitive–behavioral therapies (CBTs) can be effective treatments for posttraumatic stress disorder (PTSD) but their effectiveness is limited by high rates of premature dropout. Few studies have compared pretreatment characteristics of treatment completers and dropouts, and only one has examined these factors in Operations Iraqi Freedom and Enduring Freedom (OIF/OEF) Veterans. This study analyzed archival clinical data from 117 OEF/OIF Veterans evaluated and treated through a Veterans Affairs PTSD clinic. High numbers dropped out of treatment (68%). Treatment dropouts (n = 79) and completers (n = 38) differed significantly on Minnesota Multiphasic Personality Inventory-2 (MMPI-2) scales, PTSD symptom severity, and age. Regression analyses identified one MMPI-2 scale, TRT (negative treatment indicators), and age as unique but modest predictors of dropout. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献