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51.
《Food Control》2015
A diverse range of genetic elements has been used to develop genetically modified organisms (GMOs) over the last 18 years. Screening methods that target few elements, such as the Cauliflower Mosaic Virus 35S promoter (P-35S) and Agrobacterium tumefaciens nopaline terminator (T-nos), are not sufficient to screen GMOs. In the present study, a multiplex PCR system for all globally commercialized GM soybean events was developed to easily trace the events. For this purpose, screening elements of 24 GM soybean events were investigated and 9 screening targets were selected and divided into three individual triplex PCR systems: P-35S, ribulose-1,5-bisphosphate carboxylase small subunit promoter of Arabidopsis thaliana, T-nos, T-35S, pea E9 terminator, open reading frame 23 terminator of A. tumefaciens, proteinase inhibitor II terminator of potato, acetohydroxy acid synthase large subunit terminator of A. thaliana, and the revealed 3′ flanking sequences of DP-305423-1. The specificity of the assays was confirmed using thirteen GM soybean events as the respective positive/negative controls. The limit of detection of each multiplex set, as determined using certified reference materials of specific GM events, ranged from 0.03 to 0.5%, depending upon target. Furthermore, 26 food samples that contained soybean ingredients, which were purchased from the USA, China, Japan, and Korea, were analyzed, 17 of which contained one or more GM soybean events. These results suggest that the developed screening method can be used to efficiently track and identify 24 GM soybean events in food and feed. 相似文献
52.
《International Journal of Hydrogen Energy》2020,45(15):8640-8648
The catalytic conversion of CO2 to CH4 (Sabatier reaction) has been studied to develop an after-treatment process at vehicles exhausts. Three different formulations of Ru commercial catalysts, two in powder and one in pellets shape, were tested and characterized by means of X-ray powder diffraction, scanning electron microscopy (SEM-EDX), N2 adsorption at −196 °C and temperature-programmed reduction (TPR).Experimental results show a high CO2 conversion (XCO2 = 0.96 @ T = 280 °C) for one powder catalyst formulation whereas the other one has maximum CO2 conversion = 0.69. In both cases a high CH4 selectivity is measured. High CO2 conversion (XCO2 = 0.92 @ T = 300 °C) is obtained also with pellet catalysts but only at lower GHSV values. The different behavior of the catalysts was ascribed to the different physicochemical properties and the key parameters for the application development of the process were identified. In particular, the possibility to use pellets or monolithic reactors, thus minimizing the pressure drops in the reactor, makes possible a commercial application in the treatment of vehicles exhausts. 相似文献
53.
54.
《International Journal of Hydrogen Energy》2020,45(49):26238-26253
The demands for high-purity hydrogen required in fuel-cell applications impose new goals and challenges for design of well performing water-gas shift (WGS) catalysts. Gold-based catalysts have exhibited high activity in the WGS reaction at low temperature. Preparation of appropriate and economically viable supports with complex composition by various synthesis procedures is an attractive approach to WGS performance improvement. The effect of two different preparation methods (wet impregnation or mechanical mixing) and ceria content (10, 20 or 30 wt%) on textural, structural, surface and reductive properties and WGS activity of gold catalysts was studied. Additionally, the role of Y2O3 as a promoter of ceria was examined. Long-term stability test was carried out at 260 °C over the most active catalyst. The composition of the best performing sample (composed of about 70 wt% alumina), prepared by mechanical mixing, was considered promising in case of practical applications because of its cost efficiency. The combination of gold nanoparticles and alumina supported Y-doped ceria proved an advantageous approach for developing new catalytic formulations with high effectiveness in clean hydrogen production. 相似文献
55.
《International Journal of Hydrogen Energy》2021,46(75):37333-37339
Water electrolysis is an efficient approach for high-purity hydrogen production. However, the anodic sluggish oxygen evolution reaction (OER) always needs high overpotential and thus brings about superfluous electricity cost of water electrolysis. Therefore, exploiting highly efficient OER electrocatalysts with small overpotential especially at high current density will undoubtedly boost the development of industrial water electrolysis. Herein, we used a simple hydrothermal method to prepare a novel FeOOH–CoS nanocomposite on nickel foam (NF). The as-prepared FeOOH–CoS/NF catalyst displays an excellent OER performance with extremely low overpotentials of 306 and 329 mV at 500 and 1000 mA cm−2 in 1.0 M KOH, respectively. In addition, the FeOOH–CoS/NF catalyst can maintain excellent catalytic stability for more than 50 h, and the OER catalytic activity shows almost no attenuation no matter after 1000 repeated CV cycles or 50 h of stability test. The high catalytic activity and stability have exceeded most non-noble metal electrocatalysts reported in literature, which makes the FeOOH–CoS/NF composite catalyst have promising applications in the industrial water electrolysis. 相似文献
56.
《Journal of the European Ceramic Society》2020,40(8):3348-3353
Large transduction coefficient () is difficult to obtain in piezoelectric ceramics because these two parameters show opposite trends with compositional modifications. Herein, the Pb(Zr0.53Ti0.47)O3 ceramic powders were calcinated under different temperatures (A:830 °C, B:860 °C, and C:890 °C), and then mixed together according to different weight ratios (1A:1B:1C, 1A:2B:1C, 1A:2B:3C and 3A:2B:1C) for ceramics preparation. Both d33 and g33 are improved successfully, and the transduction coefficient with the weight ratio of 1A:2B:3C reaches up to 17,500 × 10−15 m2/N, which is 60 % higher than that with the powders calcinated under 830 °C, and at least twice those of commercial PZT-4, PZT-5A and PZT-8 ceramics. The improved transduction coefficient is owing to the enhanced piezoelectric constant and spontaneous polarization resulted from the increased grain size, relative density and the fraction of tetragonal phase. These results indicate that this is a simple but effective way to tailor the transduction coefficient in piezoelectric ceramics. 相似文献
57.
Many models of spoken word recognition posit the existence of lexical and sublexical representations, with excitatory and inhibitory mechanisms used to affect the activation levels of such representations. Bottom-up evidence provides excitatory input, and inhibition from phonetically similar representations leads to lexical competition. In such a system, long words should produce stronger lexical activation than short words, for 2 reasons: Long words provide more bottom-up evidence than short words, and short words are subject to greater inhibition due to the existence of more similar words. Four experiments provide evidence for this view. In addition, reaction-time-based partitioning of the data shows that long words generate greater activation that is available both earlier and for a longer time than is the case for short words. As a result, lexical influences on phoneme identification are extremely robust for long words but are quite fragile and condition-dependent for short words. Models of word recognition must consider words of all lengths to capture the true dynamics of lexical activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Reports an error in "Tradeoffs and Theory: The Double-Mediation Model" by Marc Scholten and Steven J. Sherman (Journal of Experimental Psychology: General, 2006 May, Vol 135[2], 237-261). This article was inadvertently printed with the incorrect title. The original title was "Tradeoffs and Conflict: The Double-Mediation Model." This title highlights the relation between tradeoffs and conflict as investigated by the authors and accounted for by their model. However, readers are asked to refer to the article by the title with which it was printed to facilitate its retrieval.. (The following abstract of the original article appeared in record 2006-06642-006.) Most theories of decision making suggest that, when options imply tradeoffs between their attributes, conflict increases as tradeoff size increases, because greater sacrifices are to be incurred in choosing one option instead of another. An alternative view is that conflict decreases as tradeoff size increases, because stronger arguments can be made for any decision. The authors propose a unified model, the double-mediation model, which combines the mediating effects of sacrifice and argumentation. Our model generally predicts an inverse U-shaped relation between tradeoff size and conflict. Results support this prediction. Also, when the decision situation increases the mediating effect of sacrifice relative to that of argumentation, the relation between tradeoff size and conflict changes in an upward direction; conversely, when the decision situation increases the mediating effect of argumentation relative to that of sacrifice, the relation changes in a downward direction. Results support these predictions as well. Commonalities and differences between our model and other formulations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
醇解技术在制备皮革加脂剂方面的研究进展 总被引:1,自引:0,他引:1
本文介绍了醇解反应的动力学、影响醇解反应收率的因素以及醇解反应在合成加脂剂方面的应用。 相似文献
60.