Preparation,alumina-pillaring and oxidation catalytic performances of synthetic Ni-saponite

Synthetic saponite containing Ni²⁺ as octahedral cations has been prepared by a simple hydrothermal procedure, and has been intercalated with Al₁₃-polycations. The catalytic performance of the pillared solids in the epoxidation of (Z)-cyclooctene and the oxidation of cyclohexanone in the presence of benzonitrile, Baeyer–Villiger reaction, using hydrogen peroxide (70%) as a clean oxidant have been studied. For comparison, Mg-saponite was synthesized under the same conditions and tested for the same reaction.     

Influence of the Addition of a Second Metal on the Catalytic Performance of Pt-Beta Agglomerated Catalyst in the Hydroisomerization of n-Octane

In this work, the hydroisomerization of n-octane on mono and bimetallic beta agglomerated zeolite based catalysts was investigated. As the metal function, platinum and combinations with nickel and tin were studied. Test reactions were carried out at 10 bar and 290–410 °C. The bimetallic catalyst with the lowest amount of Ni yielded the greatest multibranched selectivity.     

葡萄糖酸钠对萘系高效减水剂塑化水泥浆体流动性的影响(英文)

研究了掺萘系高效减水剂浆体中同时掺入葡萄糖酸钠时,对水泥浆体流动性和流动性损失的影响。适量的葡萄糖酸钠可显著提高浆体初始流动度,并降低流动度损失。采用紫外分光光度计、zeta电位仪、X衍射仪和扫描电子显微镜测试了浆体对萘系高效减水剂的吸附量、水泥颗粒表面电位、水化产物钙矾石X衍射峰值强度和微观形貌。结果表明:在同等萘系高效减水剂掺量下,葡萄糖酸钠延缓了钙矾石的生成,并与萘系减水剂在水泥颗粒表面形成竞争吸附,导致了水化过程中萘系高效减水剂消耗量的降低,增加了高效减水剂在水泥颗粒表面的有效吸附量。     

INTRODUCTION TO INCONEL ALLOY 740: AN ALLOY DESIGNED FOR SUPERHEATER TUBING IN COAL-FIRED ULTRA SUPERCRITICAL BOILERS

1. IntroductionW hile w orldw ide environm entalrestrictionsare requiring pow ercom paniesto reduce SO x,N O x andCO 2 em issions, econom ic pressuresare sim ultaneously necessitating im provem entsin the therm aleffi-ciency ofallcoal-fired plants. A ddin…     

Using artificial intelligence to model heavy plate mill rolling

This research summary discusses the application of neural networks, evolutionary strategies, and other artificial intelligence techniques in the modeling and optimization of the models used for temperature, rolling force, and torque calculation in heavy plate milling.     

Qualitative and Quantitative Comparison of Plasma Exosomes from Neonates and Adults

Exosomes are extracellular vesicles that contain nucleic acids, lipids and metabolites, and play a critical role in health and disease as mediators of intercellular communication. The majority of extracellular vesicles in the blood are platelet-derived. Compared to adults, neonatal platelets are hyporeactive and show impaired granule release, associated with defects in Soluble N-ethylmaleimide-sensitive fusion Attachment protein REceptor (SNARE) proteins. Since these proteins participate in biogenesis of exosomes, we investigated the potential differences between newborn and adult plasma-derived exosomes. Plasma-derived exosomes were isolated by ultracentrifugation of umbilical cord blood from full-term neonates or peripheral blood from adults. Exosome characterization included size determination by transmission electron microscopy and quantitative proteomic analysis. Plasma-derived exosomes from neonates were significantly smaller and contained 65% less protein than those from adults. Remarkably, 131 proteins were found to be differentially expressed, 83 overexpressed and 48 underexpressed in neonatal (vs. adult) exosomes. Whereas the upregulated proteins in plasma exosomes from neonates are associated with platelet activation, coagulation and granule secretion, most of the underexpressed proteins are immunoglobulins. This is the first study showing that exosome size and content change with age. Our findings may contribute to elucidating the potential “developmental hemostatic mismatch risk” associated with transfusions containing plasma exosomes from adults.     

Application of titanium machining chips in welding consumables for wear-resistant hardfacing

Equipment of sugar cane plants and mineral extraction are submitted to severe abrasive wear conditions. Welded hardfacings are usually applied to repair this kind of damage, where commercial chromium/carbon-rich welding consumables have usually been employed. In the present work we investigated the microstructure of experimental hardfacings made by addition of residues (chips) collected from the machining of ASTM F67 (unalloyed Ti, grade 4) alloy. Mixtures with different carbide-formers (Cr/Nb ferro-alloys) were also tested. Two layers of ‘pure’ chips (Ti), chips plus Fe–Cr (Ti–Cr), and chips plus Fe–Nb (Ti–Nb) were applied on low-carbon steel specimens by the GTAW/TIG process. The microstructure of hardfacing layers was observed by optical and scanning electron microscopy (SEM) equipped with EDS microanalysis. The microstructural characterization has determined that carbide distributions change significantly with the chemical nature of the hardfacing. SEM observations coupled with EDS microanalysis have confirmed the formation of complex carbides within the metal weld, whose stoichiometry was determined by X-ray diffraction (XRD) analysis. Mixed carbides of MC type and some cementite have been found. As a result it was suggested that use of ASTM F67 chips as carbide formers for composition of welding consumables can contribute to improved wear resistance of hardfacings, if compared with traditional chromium-based hardfacings.     

Computational Shelf-Life Dating: Complex Systems Approaches to Food Quality and Safety

Shelf-life is defined as the time that a product is acceptable and meets the consumers expectations regarding food quality. It is the result of the conjunction of all services in production, distribution, and consumption. Shelf-life dating is one of the most difficult tasks in food engineering. Market pressure has lead to the implementation of shelf-life by sensory analyses, which may not reflect the full quality spectra. Moreover, traditional methods for shelf-life dating and small-scale distribution chain tests cannot reproduce in a laboratory the real conditions of storage, distribution, and consumption on food quality. Today, food engineers are facing the challenges to monitor, diagnose, and control the quality and safety of food products. The advent of nanotechnology, multivariate sensors, information systems, and complex systems will revolutionize the way we manage, distribute, and consume foods. The informed consumer demands foods, under the legal standards, at low cost, high standards of nutritional, sensory, and health benefits. To accommodate the new paradigms, we herein present a critical review of shelf-life dating approaches with special emphasis in computational systems and future trends on complex systems methodologies applied to the prediction of food quality and safety.     

Operating conditions for the electrolytic disinfection of process wash water from the fresh-cut industry contaminated with E. coli o157:H7

The effect of operating conditions (current density, recirculation flow rate and electrode doping level) on the efficacy of boron-doped diamond (BDD) electrodes to inactivate microorganisms and decrease chemical oxygen demand (COD) was studied in lettuce process wash water with a COD of 725 mg/L and inoculated with a 5-strain cocktail of Escherichia coli O157:H7. Changes in pathogen population, COD, pH, temperature, redox potential, and free and total chlorine were monitored in process wash water during treatments. Considering the specific characteristics of the washing step included in the fresh-cut processing, the disinfection of process wash water should be of fast action. A biphasic with a shoulder model was used to estimate shoulder length (Sl), log-linear inactivation rates (k_max1, k_max2), lowest population (N_f) and highest log reduction (HLR). Current density clearly influenced Sl, and k_max2; recirculation flow rate influenced Sl, k_max1, k_max2 and COD depletion; and doping level influenced N_f. No relationship was observed between inactivation parameters and chlorine concentration. Conditions including high current density (180 mA/cm²), high flow rate (750 l/h) and high doping level (8 000 μmol/mol) seems to provide a disinfection efficiency suitable to decrease the chance of bacterial cross contamination in the fresh-cut industries while saving on water consumption and decreasing the amount of wastewater effluents.