Thermodynamic Properties of Superionic Phase Ag<Subscript>4</Subscript>HgSe<Subscript>2</Subscript>I<Subscript>2</Subscript> Determined by the EMF Method

Triangulation of the Ag-Hg-Se-I system in the vicinity of quaternary phase Ag₄HgSe₂I₂ was performed by differential thermal analysis, X-ray diffraction and electromotive force (EMF) methods. The spatial position of the phase region Ag₄HgSe₂I₂-Se-HgI₂ regarding the figurative point of silver was used to write the chemical reaction of formation of Ag₄HgSe₂I₂. The EMF measurements were carried out by applying an electrochemical cell: (–) C|Ag|Ag₂GeS₃ glass|Ag₄HgSe₂I₂, HgI₂, Se|C (+), where C is graphite and Ag₂GeS₃ glass is the fast purely Ag⁺ ions conducting electrolyte. The linear dependence of the EMF of the electrochemical cell on temperature was used to determine the standard thermodynamic values of Ag₄HgSe₂I₂ for the first time.     

Corrosive effects of the electromagnetic induction caused by the high voltage power lines on buried X70 steel pipelines

This paper diagnoses the corrosive effects of the electromagnetic induction caused by double circuit high voltage power lines (HVPL) on the buried X70 steel pipelines. To achieve this objective, firstly the electromagnetic interference between the double circuit HVPL and the X70 steel pipeline (the distribution of the magnetic field and the induced AC current densities in the buried X70 steel pipeline) and the factors affecting this interference such as the vertical distance between the double circuit HVPL and the X70 steel pipeline, and the conductor phase sequence orientation were studied. Then, electrochemical measurements were used to characterize the corrosion polarization properties of X70 steel in simulated soil at various AC current densities. The results show that with an increase in the AC current density, the corrosion rate of the X70 steel increased, indicating that the induced AC current density has accelerated the corrosion degree of X70 steel, by comparison with that in the absence of the AC current density. We can conclude from these results that the electromagnetic induction caused by the double circuit high voltage power lines affects the electrochemical characteristic of the X70 steel pipeline and accelerates the corrosion of the pipeline.     

Biodiesel production,characterization, and performance: A hands-on project for first-year students

Biodiesel fuel production and use has been used as the focal point of a semester-long, project-based introductory engineering course at Rowan University. Students worked in teams to conduct a series of laboratory investigations through which they explored the engineering aspects of biodiesel production and purification, properties characterization, quality control and performance testing. The experiments were designed to be cost–effective and transferrable.The laboratory experiments were conducted within the How People Learn framework. An assessment instrument was used as a pre- and post-evaluation method to assess learning outcomes. Students’ gained significantly in learning outcomes areas related to the application of mathematics, science and engineering principles; designing and conducting experiments; analyzing and interpreting experimental data, and solving engineering problems.     

Catalyst development for the selective oxidation of ethoxylates to their corresponding ether carboxylic acids

The aerobic selective oxidation of polyethoxylates to their corresponding carboxylic acids was investigated using supported Au-based catalysts in aqueous alkaline solution. Introduction of Pt as secondary metal to the titania supported Au catalyst led to a significant boost in activity while maintaining total selectivity. A screening of different preparation methods and metal ratios led to a titania supported AuPt catalyst with a substantially reduced intermediate leaching of the catalytically active metals. A long-term stability study showed no noble metal loss of this particular catalyst after a set of repeated batches, but still revealed a distinct loss in activity due sintering of the metal nanoparticles. By switching from titania to ceria as support material, intermediate metal leaching could be prevented completely while maintaining total selectivity and further enhancing the activity.     

Free,esterified, and insoluble-bound phenolic acids in white and red Korean ginsengs (Panax ginseng C.A. Meyer)

Phenolic acids of dried white and red ginsengs were extracted and fractionated into free, esterified, and insoluble-bound forms. The contents of individual phenolic acids in different forms were quantified by gas–liquid chromatography. Identification of all phenolic acids was confirmed by gas chromatography–mass spectrometry and comparison of gas chromatographic retention times. Twelve different phenolic acids as free, esterified, and insoluble-bound forms were identified in Korean ginsengs. Total phenolic acids in white and red ginsengs were 27.2 and 26.8 mg/100 g, respectively. Seven free phenolic acids were identified and their total contents in white and red ginsengs were 4.70 and 4.14 mg/100 g, respectively. trans-Ferulic acid was the predominant free phenolic acid, representing 47.9 and 57.7% of total free phenolic acids in white and red ginsengs, respectively. Esterified phenolic acids represented 71.9 and 77.1% of total phenolic acids in white and red ginsengs, respectively. The most predominant esterified phenolic acids were cis-ferulic acid and trans-ferulic acid. Total insoluble-bound phenolic acid contents in white and red ginsengs were 2.93 and 1.99 mg/100 g, respectively. Ferulic acid (cis and trans isomers) was also the major insoluble-bound phenolic acids. This paper represents the first report of systematic identification and quantification of phenolic acids in different forms in white and red Korean ginsengs.     

Morphological features of porous silicon carbide obtained via a carbothermal method

Samples of porous silicon carbide were obtained using sucrose or carbon and aerosil or silica mesoporous molecular sieves (SBA‐3, SBA‐15, KIT‐6 and MCF). Fibers content in silicon carbide samples is higher when the mesopore surface area of carbon materials derived from carbon‐silica composites is lower. Based on the found correlation between the morphology and porosity of SiC and mesopore surface area of the carbon component in the composites, a templating action of carbon in carbothermal reduction was suggested.     

Comparable Characterization of Nanocellulose Extracted from Bleached Softwood and Hardwood Pulps

In this study, the characteristics of nanocellulose extracted from bleached softwood and hardwood pulps by formic acid hydrolysis followed by TEMPO-mediated oxidation were compared using transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared analysis (FT-IR), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA). The experimental results showed that the nanocellulose products derived from spruce pulp exhibited a relatively larger particle size, higher crystallinity, and higher thermal stability, compared with the corresponding products obtained from aspen pulp under the same conditions. Furthermore, the study helped establish that the properties of the nanocellulose products were highly dependent on the nature of the starting materials under identical processing conditions.