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排序方式: 共有662条查询结果,搜索用时 15 毫秒
651.
Donna Post Guillen Erik R. Coats Armando G. McDonald Kevin Feris 《JOM Journal of the Minerals, Metals and Materials Society》2018,70(10):1946-1957
A concept is outlined for the production of materials/commodities from a polluting waste. A preliminary evaluation is presented for a proposed integrated dairy farm manure management system consisting of a two-stage anaerobic digester coupled with a polyhydroxyalkanoate reactor, algae cultivation system (ACS) and a biomass treatment system, such as fast-pyrolysis or hydrothermal liquefaction, to sequester carbon, nitrogen and phosphorus into value-added products (e.g., bioplastics, biogas, fertilizer, soil amendment and livestock bedding) rather than releasing them into the environment. Mass flows through the system are presented for a 10,000-cow dairy. The integrated manure treatment system can reduce the amount of nitrogen and phosphorus released from the manure by 50.9% and 38.1%, respectively. Without an ACS, the reduction drops to 19% and 27%, respectively. Greenhouse gas emissions can potentially be reduced by 44,200 MT CO2e/year over the referenced open lot dairy. 相似文献
652.
A Highly Efficient Oxygen Evolution Catalyst Consisting of Interconnected Nickel–Iron‐Layered Double Hydroxide and Carbon Nanodomains 下载免费PDF全文
Shengming Yin Wenguang Tu Yuan Sheng Yonghua Du Markus Kraft Armando Borgna Rong Xu 《Advanced materials (Deerfield Beach, Fla.)》2018,30(5)
In this work, a one‐pot solution method for direct synthesis of interconnected ultrafine amorphous NiFe‐layered double hydroxide (NiFe‐LDH) (<5 nm) and nanocarbon using the molecular precursor of metal and carbon sources is presented for the first time. During the solvothermal synthesis of NiFe‐LDH, the organic ligand decomposes and transforms to amorphous carbon with graphitic nanodomains by catalytic effect of Fe. The confined growth of both NiFe‐LDH and carbon in one single sheet results in fully integrated amorphous NiFe‐LDH/C nanohybrid, allowing the harness of the high intrinsic activity of NiFe‐LDH due to (i) amorphous and distorted LDH structure, (ii) enhanced active surface area, and (iii) strong coupling between the active phase and carbon. As such, the resultant NiFe‐LDH/C exhibits superior activity and stability. Different from postdeposition or electrostatic self‐assembly process for the formation of LDH/C composite, this method offers one new opportunity to fabricate high‐performance oxygen evolution reaction and possibly other catalysts. 相似文献
653.
Angélica Domínguez-Aragón Claudia A. Hernández-Escobar Alejandro Vega-Rios E. Armando Zaragoza-Contreras 《Journal of Materials Science: Materials in Electronics》2018,29(18):15329-15338
Polyaniline, polydiphenylamine, and two copolymers with precursor monomers molar ratios of 1:1 and 3:1 (anilinium dodecyl sulfate (P1):diphenylamine) were synthesized via oxidative polymerization in a water/ethanol interfacial system. The morphology characterization and physicochemical properties showed that the copolymers share polyaniline or polydiphenylamine characteristics, depending on the monomer molar ratio. The electroactivity characterization indicated that the polydiphenylamine (PDPA) repeating units provided the copolymers with better cycling stability, whereas PAni repeating units reduced resistance and improved storage capacity, generating a synergistic interaction. Particularly, the copolymer with the highest content of P1, showed a specific capacitance of 341.93 F g?1, with a 74.5% capacitance retention after 500 cycles, which suggests a feasible application in electrodes for supercapacitor design. 相似文献
654.
Luca Pulina Armando Tacchella 《Annals of Mathematics and Artificial Intelligence》2011,62(3-4):403-425
The adoption of Artificial Neural Networks (ANNs) in safety-related applications is often avoided because it is difficult to rule out possible misbehaviors with traditional analytical or probabilistic techniques. In this paper we present NeVer, our tool for checking safety of ANNs. NeVer encodes the problem of verifying safety of ANNs into the problem of satisfying corresponding Boolean combinations of linear arithmetic constraints. We describe the main verification algorithm and the structure of NeVer. We present also empirical results confirming the effectiveness of NeVer on realistic case studies. 相似文献
655.
Rosa Perestrelo Ying Lu Sónia A.O. Santos Armando J.D. Silvestre Carlos P. Neto José S. Câmara Sílvia M. Rocha 《Food chemistry》2012
This study represents the first phytochemical research of phenolic components of Sercial and Tinta Negra Vitis vinifera L. The phenolic profiles of Sercial and Tinta Negra V. vinifera L. grape skins (white and red varieties, respectively) were established using high performance liquid chromatography–diode array detection–electrospray ionisation tandem mass spectrometry (HPLC–DAD–ESI-MSn), at different ripening stages (véraison and maturity). A total of 40 phenolic compounds were identified, which included 3 hydroxybenzoic acids, 8 hydroxycinnamic acids, 4 flavanols, 5 flavanones, 8 flavonols, 4 stilbenes, and 8 anthocyanins. For the white variety, in both ripening stages, hydroxycinnamic acids and flavonols were the main phenolic classes, representing about 80% of the phenolic composition. For red variety, at véraison, hydroxycinnamic acids and flavonols were also the predominant classes (71%), but at maturity, anthocyanins represented 84% of the phenolic composition. As far as we know, 10 compounds were reported for the first time in V. vinifera L. grapes, namely protocatechuic acid-glucoside, p-hydroxybenzoyl glucoside, caftaric acid vanilloyl pentoside, p-coumaric acid-erythroside, naringenin hexose derivate, eriodictyol-glucoside, taxifolin-pentoside, quercetin-glucuronide-glucoside, malylated kaempferol-glucoside, and resveratrol dimer. These novel V. vinifera L. grape components were identified based on their MSn fragmentation profile. This data represents valuable information that may be useful to oenological management and to valorise these varieties as sources of bioactive compounds. 相似文献
656.
Untargeted Metabolomic Screen Reveals Changes in Human Plasma Metabolite Profiles Following Consumption of Fresh Broccoli Sprouts 下载免费PDF全文
657.
At a time when the need to reduce costs has become part of the day-to-day reality of all educational institutions, it is unthinkable to continue to manually perform those tasks (i.e., the creation of timetables) that can be automated and optimized. The automatic creation of timetables for educational institutions is one of the most studied problems by the scientific community. However, almost all studies have been based on very simplified models of reality that have no practical application. A realistic model of the problem, robust algorithms that are able to find valid solutions in highly restricted environments, and optimization methods that are able to quickly provide quality results are key factors to consider when attempting to solve this (real) problem faced by educational institutions. This paper presents a summary of the work performed by Bullet Solutions over the last few years, from the first stage of understanding and modelling the problem to the final analysis of the results obtained using the developed software under real conditions. 相似文献
658.
659.
Viso González ME Solano L Sánchez A Portillo Z Llovera D 《Archivos latinoamericanos de nutrición》2005,55(1):47-54
Leptin is closely related to obesity and its complications. In order to determine serum levels of this hormone in children and adolescents, and its associations to age, gender, socioeconomic status, nutritional anthropometrical status and dietary intake, 166 children and adolescents (91 normal and 75 obese, aged 2 to 15 years), from low socioeconomic status were assessed. A socioeconomic evaluation (Grafffar-Mendez C method), dietary intake (24 hour recalls), anthropometrical assessment and leptin by ELISA were performed. Normal or eutrophic was defined as weight for height (W/H) or Body mass index (BMI) and fatty area between 10th and 90th percentile. Obesity when indicators were over 90th percentile. Leptin was significantly higher in obese than in normal, without differences by gender or age. Leptin percentile distribution showed 11.53 microg/L and 24.29 microg/L as 90th percentile for normal and obese children, respectively. There was a tendency to inverse correlation among leptin, fat dietary intake and waist-thigh ratio. Excessive fat intake was associated to lower serum leptin. Results suggest that obese children had leptin resistance, independently of age and gender. It is recommended to develop nutritional education programs regarding obesity and dietary intake in order to prevent and control infantile obesity. 相似文献
660.