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991.
Tiago Bender Wermuth Mario Norberto Baibich Tania Maria Hubert Ribeiro Carlos Pérez Bergmann 《Ceramics International》2018,44(5):4758-4765
We studied the molar ratio effects of niobium and potassium precursors on the structure and morphology of potassium niobate powders prepared via microwave-assisted hydrothermal synthesis (MaHS). KNbO3 nanostructures in the form of nanotowers and nanocubes were obtained at reduced synthesis times (30–240 min). The products were characterized via XRD, Raman spectroscopy, SEM, and TEM; band gap calculations used diffuse reflectance data. The results indicate that KNbO3 nanostructures were obtained with crystallite sizes ranging from 33 to 52 nm. An orthorhombic crystalline structure was formed from the increase of KOH at a molar ratio Nb2O5:KOH (1:8 to 1:16 M). The band-gap of 3.1–3.3 eV has potential use in photodegradation applications. 相似文献
992.
Use of coffee by‐products for the cultivation of Pleurotus citrinopileatus and Pleurotus salmoneo‐stramineus and its impact on biological properties of extracts thereof 下载免费PDF全文
Ana C. Freitas Mariana B. Antunes Dina Rodrigues Sérgio Sousa Manuela Amorim Maria F. Barroso Ana Carvalho Sandra M. Ferrador Ana M. Gomes 《International Journal of Food Science & Technology》2018,53(8):1914-1924
Incorporating spent coffee grounds (SCGs), a by‐product from coffee brewing, in growth substrate of beneficial edible mushrooms is an approach that has to be further studied due to its potential positive outcomes: environmental impact mitigation, production costs reduction and beneficial impact on consumer health. Hence, cultivation of Pleurotus citrinopileatus and Pleurotus salmoneo‐stramineus was tested using SCG which enabled maximum production yield of P. citrinopileatus which was of 25.1% (w/w). Variable antidiabetic potential was observed between aqueous and enzymatic extracts (3.8%–29% inhibition) regardless species and substrates, whereas aqueous extract of P. citrinopileatus grown in substrate without SCG stood out presenting the highest antioxidant activity and inhibition activity of angiotensin I‐converting enzyme (IC50 = 123 μg mL?1). Ethanolic and aqueous extracts of both Pleurotus species grown in the presence or absence of SGC proved to be an interesting prebiotic source for growth of Bifidobacterium animalis Bo in comparison with fructooligosaccharides (FOS). 相似文献
993.
994.
Volatile fatty acids production from cheese whey: influence of pH,solid retention time and organic loading rate 下载免费PDF全文
995.
It was found in a commercial single crystal superalloy CMSX-4 that preferential orientation of the γ′ rafting in dendrite core was not dependent on the sign of the applied stress σA, but on the sign of the sum of the applied stress σA and a critical equivalent stress σc. This critical equivalent stress σc caused by material inhomogeneity has been predicted previously; however it was first determined experimentally to be in the range 39.8–47.2 MPa in the present study. Moreover, it qualitatively demonstrated that the critical equivalent stress σc played a significant role in the creep behavior of superalloys at high temperature and low stress. 相似文献
996.
This study reports on the development and validation of measurement scales to study the different roles fulfilled by ICT coordinators. Based on a review of the literature, a 24 item questionnaire was constructed and administered to a sample of 177 Flemish ICT coordinators working in primary education. Exploratory factor analysis revealed a four-factor solution: the ICT coordinator as a planner, a budgeter, a technician, and an educationalist. Qualitative data corroborated these roles. This study provides a quantitative measure of the different roles assumed by ICT coordinators in practice. The implications of our findings for schools, researchers and policy makers are discussed. 相似文献
997.
Effect of addition of Agaricus blazei mushroom residue to milk enriched with Omega‐3 on the prevention of lipid oxidation and bioavailability of bioactive compounds after in vitro gastrointestinal digestion 下载免费PDF全文
Ana Carolina P. Vital Camila Croge Sandra Maria Gomes‐da‐Costa Paula T. Matumoto‐Pintro 《International Journal of Food Science & Technology》2017,52(6):1483-1490
The residue from a hydroalcoholic extract of the mushroom Agaricus blazei (MAR) was evaluated for phenolic compounds, flavonoids and antioxidant activity. The ability of MAR to slow the oxidation of Omega‐3 resulting from light exposure in milk matrix, and its bioavailability after in vitro digestion was investigated. MAR presented phenolic compounds and flavonoids and showed antioxidant activity. At each concentration, addition of MAR to Omega‐3‐supplemented milk inhibited the production of conjugated dienes and malonaldehyde compared with samples without MAR. The bioavailability assay showed that polyphenols were still present after in vitro digestion and had antioxidant activity. 相似文献
998.
João Custódio James Broughton Helena Cruz Pat Winfield 《International Journal of Adhesion and Adhesives》2009,29(2):167-172
Long-term durability of a structural adhesive joint is an important requirement, because it has to be able to support the required design loads, under service conditions, for the planed lifetime of the structure. One way of improving bond durability is through the use of surface treatments prior to bonding, which will activate the adherends’ surface, making it more receptive to the adhesive. In this study, the effects of two surface pre-treatments (corona discharge and flame ionization) on three timbers (maritime pine, iroko, and European oak) were evaluated quantitatively through contact angle measurements. These measurements allowed the determination of the changes in the timber surface thermodynamic characteristics, thus indicating which pre-treatment performed better. The results showed that both techniques increased each timber's surface free energy, which could translate into a durability enhancement of bonded joints. Overall, the corona-discharge treatment looks more promising, since this treatment leads to a bigger increase in the timber's surface energy, especially in its polar component, whilst also tended to be less species specific, less susceptible to variation, and the treatment effects lasted longer for this type of treatment. 相似文献
999.
Sartori Luisa; Becchio Cristina; Bulgheroni Maria; Castiello Umberto 《Canadian Metallurgical Quarterly》2009,35(5):1490
Four experiments investigated the influence of a sudden social request on the kinematics of a preplanned action. In Experiment 1, participants were requested to grasp an object and then locate it within a container (unperturbed trials). On 20% of trials, a human agent seated nearby the participant unexpectedly stretched out her arm and unfolded her hand as if to ask for the object (perturbed trials). In the remaining 3 experiments, similar procedures were adopted except that (a) the human was replaced by a robotic agent, (b) the gesture performed by the human agent did not imply a social request, and (c) the gaze of the human agent was not available. Only when the perturbation was characterized by a social request involving a human agent were there kinematic changes to the action directed toward the target. Conversely, no effects on kinematics were evident when the perturbation was caused by the robotic agent or by a human agent performing a nonsocial gesture. These findings are discussed in the light of current theories proposed to explain the effects of social context on the control of action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Marco Giorgetti Mario Berrettoni Maria Luisa Saladino Eugenio Caponetti 《Journal of Materials Science》2009,44(6):1572-1579
Nanopowders of Yttrium Aluminium Garnet doped with neodymium (Nd:YAG) were investigated by X-Ray Absorption Fine Structure
(XAFS) at the Nd LIII edge in the 1.3–20.8% doping range. XANES spectra appear similar in the full range of the Nd concentration. However, a significant
decrease in the white line intensity of XANES is revealed as the quantity of Nd doping ions increases. Plotting the white
line intensity as a function of Nd doping ions reveals two linear trends with two different slopes, identifying a threshold
value where the neodymium concentration reaches 5 at.% This experimental finding provides support for the existence of a double
doping regime in Nd:YAG nanopowders.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献