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91.
Luciano Atzori Maria Giorgia Cutrufello Daniela Meloni Barbara Onida Delia Gazzoli Andrea Ardu Roberto Monaci Maria Franca Sini Elisabetta Rombi 《Frontiers of Chemical Science and Engineering》2021,15(2):251-268
Nanosized NiO,CeO2 and NiO-CeO2 mixed oxides with different Ni/Ce molar ratios were prepared by the soft template method.All the samples were characterized by different techniques as to their chemical composition,structure,morphology and texture.On the catalysts submitted to the same reduction pretreatment adopted for the activity tests the surface basic properties and specific metal surface area were also determined.NiO and CeO2 nanocrystals of about 4 nm in size were obtained,regardless of the Ni/Ce molar ratio.The Raman and X-ray photoelectron spectroscopy results proved the formation of defective sites at the NiO-CeO2 interface,where Ni species are in strong interaction with the support.The microcalorimetric and Fourier transform infrared analyses of the reduced samples highlighted that,unlike metallic nickel,CeO2 is able to effectively adsorb CO2,forming carbonates and hydrogen carbonates.After reduction in H2 at 400°C for 1 h,the catalytic performance was studied in the CO and CO2 co-methanation reaction.Catalytic tests were performed at atmospheric pressure and 300°C,using CO/CO2/H2 molar compositions of 1/1/7 or 1/1/5,and space velocities equal to 72000 or 450000 cm3?h-1?gcat-1.Whereas CO was almost completely hydrogenated in any investigated experimental conditions,CO2 conversion was strongly affected by both the CO/CO2/H2 ratio and the space velocity.The faster and definitely preferred CO hydrogenation was explained in the light of the different mechanisms of CO and CO2 methanation.On a selected sample,the influence of the reaction temperature and of a higher number of space velocity values,as well as the stability,were also studied.Provided that the Ni content is optimized,the NiCe system investigated was very promising,being highly active for the COx co-methanation reaction in a wide range of operating conditions and stable(up to 50 h)also when submitted to thermal stress. 相似文献
92.
Priscila Strapasson Delia M. Pinto-Zevallos Sandra M. Da Silva Gomes Paulo H. G. Zarbin 《Journal of chemical ecology》2016,42(8):806-813
Transgenic soybean plants (RR) engineered to express resistance to glyphosate harbor a variant of the enzyme EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) involved in the shikimic acid pathway, the biosynthetic route of three aromatic amino acids: phenylalanine, tyrosine, and tryptophan. The insertion of the variant enzyme CP4 EPSPS confers resistance to glyphosate. During the process of genetic engineering, unintended secondary effects are likely to occur. In the present study, we quantified volatile organic compounds (VOCs) emitted constitutively or induced in response to herbivory by the soybean looper Chrysodeixis includens in transgenic soybean and its isogenic (untransformed) line. Since herbivore-induced plant volatiles (HIPVs) are known to play a role in the recruitment of natural enemies, we assessed whether changes in VOC profiles alter the foraging behavior of the generalist endoparasitic larval parasitoid, Meteorus rubens in the transgenic line. Additionally, we assessed whether there was a difference in plant quality by measuring the weight gain of the soybean looper. In response to herbivory, several VOCs were induced in both the conventional and the transgenic line; however, larger quantities of a few compounds were emitted by transgenic plants. Meteorus rubens females were able to discriminate between the odors of undamaged and C. includens-damaged plants in both lines, but preferred the odors emitted by herbivore-damaged transgenic plants over those emitted by herbivore-damaged conventional soybean plants. No differences were observed in the weight gain of the soybean looper. Our results suggest that VOC-mediated tritrophic interactions in this model system are not negatively affected. However, as the preference of the wasps shifted towards damaged transgenic plants, the results also suggest that genetic modification affects that tritrophic interactions in multiple ways in this model system. 相似文献
93.
Development of Potent Inhibitors of the Mycobacterium tuberculosis Virulence Factor Zmp1 and Evaluation of Their Effect on Mycobacterial Survival inside Macrophages 下载免费PDF全文
Dr. Marco Paolino Dr. Margherita Brindisi Dr. Alessandra Vallone Prof. Stefania Butini Prof. Giuseppe Campiani Dr. Chiara Nannicini Germano Giuliani Prof. Maurizio Anzini Dr. Stefania Lamponi Prof. Gianluca Giorgi Prof. Diego Sbardella Dr. Davide M. Ferraris Prof. Stefano Marini Prof. Massimo Coletta Dr. Ivana Palucci Dr. Mariachiara Minerva Prof. Giovanni Delogu Dr. Ilaria Pepponi Dr. Delia Goletti Prof. Andrea Cappelli Sandra Gemma Dr. Simone Brogi 《ChemMedChem》2018,13(5):422-430
The enzyme Zmp1 is a zinc‐containing peptidase that plays a critical role in the pathogenicity of Mycobacterium tuberculosis. Herein we describe the identification of a small set of Zmp1 inhibitors based on a novel 8‐hydroxyquinoline‐2‐hydroxamate scaffold. Among the synthesized compounds, N‐(benzyloxy)‐8‐hydroxyquinoline‐2‐carboxamide ( 1 c ) was found to be the most potent Zmp1 inhibitor known to date, and its binding mode was analyzed both by kinetics studies and molecular modeling, identifying critical interactions of 1 c with the zinc ion and residues in the active site. The effect of 1 c on intracellular Mycobacterium survival was assayed in J774 murine macrophages infected with M. tuberculosis H37Rv or M. bovis BCG and human monocyte‐derived macrophages infected with M. tuberculosis H37Rv. Cytotoxicity and genotoxicity were also assessed. Overall, inhibitor 1 c displays interesting in vitro antitubercular properties worthy of further investigation. 相似文献
94.
Delia Teresa Sponza Oguzhan Gok 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(5):658-672
BACKROUND: In Izmir, Turkey, wastewaters from the petrochemical industry are treated using conventional activated sludge systems. A significant proportion of poly‐aromatic hydrocarbons (PAHs) with high‐molecular weights remains in this treatment system and inhibits the biological activity. Biosurfactants increase PAHs degradation by enhancing the solubility of the petroleum components. The aerobic inhibition kinetics of PAHs has not previously been investigated in the presence of biosurfactants for a real petrochemical industry wastewater. RESULTS: Among the kinetic models used (Monod‐type, zero, first‐order and second‐order) it was found that the Monod kinetic was effective for describing the biodegradation of PAHs in petrochemcal industry wastewater in the presence of three biosurfactants, namely Rhamnolipid (RD), Surfactine (SR) and Emulsan (EM) in an aerobic activated sludge reactor (AASR). The maximum PAH removal rate (Rmax) and specific growth rate of PAH degrading bacteria (µmax) increased, while the half saturation concentration of PAH (Ks) decreased at 15 mg L?1 RD concentration compared with the control without biosurfactant at a sludge retention time (SRT) of 25 days. CONCLUSION: PAH oxidation is typified by competitive inhibition at RD concentrations > 15 mg L?1 resulting in increases in Ks values with PAH accumulation. Low inhibition constant (KID) values reflect difficulties in the metabolizability of PAHs. Metabolite production decreased at RD = 25 mg L?1 in the PAHs indeno (1,2,3‐cd) pyrene (IcdP), flourene (FLN), phenanthrene (PHE) and benzo(a)pyrene (BaP). Copyright © 2011 Society of Chemical Industry 相似文献
95.
Tested whether having tokens (Ts) adopt the role of judge reduces cognitive deficits; examined several hypotheses to explain these deficits. In 3 experiments, Ss were asked to remember as many as possible of opinions exchanged in a group interaction with 3 actors. Experiment 1 demonstrated that judging majority members helped gender Ts improve their memory and ruled out self-denigration as a mediator of token deficits. Experiment 2 indicated that judging others was effective regardless of whether the others were said to know about it or not, ruling out insulation from evaluative scrutiny as a viable mediator for the judge role. Experiment 3 suggested the judge role restores completely the Ts' cognitive capacities and ruled out heightened responsibility as an explanation for the improved memory on judges. This work suggests that Ts may perform better if they can restructure cognitively their social environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Perkins Kenneth A.; Grobe James E.; D'Amico Delia; Fonte Carolyn; Wilson Annette S.; Stiller Richard L. 《Canadian Metallurgical Quarterly》1996,4(2):157
The purposes of this study were to determine if smokers wanting to quit smoking would use a low-dose nicotine nasal spray (i.e., acceptability) and what effect this spray use would have on withdrawal during the 1st week of cessation. Smokers (n?=? 52) were assigned double-blind to either placebo or nicotine spray (1.5 μg/kg. or approx. 0.1 mg, per spray) for ad lib use during the first week of cessation. All received group behavioral counseling. There was no difference in continuous 1-week abstinence (daily COa? 相似文献
97.
Celia M Sylos Delia B Rodriguez-Amaya 《Journal of the science of food and agriculture》1989,49(2):167-172
Surveys of major Brazilian foodstuffs demonstrated that peanuts and peanut products continue to be very susceptible to aflatoxin contamination. To prevent, or at least minimise, the problem the aflatoxins need to be monitored by a rapid and inexpensive screening method. The AOAC Romer method has been used and found highly reliable. However, the clean-up step utilises anhydrous FeCl3 and basic CuCO3 which are expensive and not readily available in Brazil. Thus, the extraction (with a mixture of 270 ml methanol plus 30ml 40 g litre?1 aqueous KCl) and clean-up (150 ml 100 g litre?1 aqueous CuSO4) steps of the method of Soares and Rodriguez-Amaya (1985) were combined with the AOAC minicolumn to provide a rapid, inexpensive screening technique. Fifty-two sample lots of peanuts and peanut products were screened by this and Romer's method, and the results were in complete agreement: 28 samples were negative, four < 20 μg kg?1, 12 in the range 20–50 μg kg?1, three in the range 50–100 μg kg?1 and 5 >100 μg kg?1. The results also agreed well when the extracts obtained by the two methods were submitted to quantitative TLC. 相似文献
98.
他们一边一本正经地告诫大小“盆”友们千万不能吞灯泡,一边又暗自得意地观望着是否有人不信邪。他们就是传说中神出鬼没的以折腾灯泡如此邪恶的活动为乐子的灯泡党!“吞灯泡门”之后,灯泡党名震江湖。今天,灯泡党重出江湖!还好,这一次,与邪恶无关。 相似文献
99.
This study evaluates the effectiveness of the Black Spot Programs in Western Australia. Reduction in crash rate at the treated locations and the economic benefits of these treatments were assessed. The results showed that the programs have been effective overall, reducing all reported crash rate by 15%. The estimated crash cost savings were 50.8 million Australian dollars, of which 89% could be attributed to the reduction in casualty crashes. This led to net savings to the community of 40.4 million Australian dollars ($35.1 million attributable to casualty crashes) after subtracting the capital costs of treating sites, maintenance and operating costs. The benefit cost ratio across all treatment sites was 4.9. Evaluation of the treatments has identified some effective treatment types and others without any significant change in either the rate or cost of crashes. The latter could be due to insufficient number of sites that received the treatment, the post-treatment period being relatively short, or the treatments genuinely had little impact on road safety. Findings of this study provide objective information for the development of effective strategies on road safety investment. 相似文献