A thermodynamic investigation of adsorbate‐adsorbate interactions of carbon dioxide on nanostructured carbons

A thermodynamic study of carbon dioxide adsorption on a zeolite‐templated carbon (ZTC), a superactivated carbon (MSC‐30), and an activated carbon (CNS‐201) was carried out at temperatures from 241 to 478 K and pressures up to 5.5?10⁶ Pa. Excess adsorption isotherms were fitted with generalized Langmuir‐type equations, allowing the isosteric heats of adsorption and adsorbed‐phase heat capacities to be obtained as a function of absolute adsorption. On MSC‐30, a superactivated carbon, the isosteric heat of carbon dioxide adsorption increases with occupancy from 19 to 21 kJ?mol^?1, before decreasing at high loading. This increase is attributed to attractive adsorbate–adsorbate intermolecular interactions as evidenced by the slope and magnitude of the increase in isosteric heat and the adsorbed‐phase heat capacities. An analysis of carbon dioxide adsorption on ZTC indicates a high degree of binding‐site homogeneity. A generalized Law of Corresponding States analysis indicates lower carbon dioxide adsorption than expected. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1026–1033, 2018     

Cyclometalated iridium(III) complexes with 5-acetyl-2-phenypyridine derived ligands for red phosphorescent OLEDs

A series of new iridium complexes with 5-acetyl-2-phenylpyridine derivatives as ligands was developed. The complexes exhibited high EL performance when applied to OLEDs. These materials showed red emission with a peak at 575–636 nm. In particular, one of the devices in this study showed a maximum luminous efficiency, maximum power efficiency, external quantum efficiency and CIE coordinates of 29.0 cd/A, 6.13 lm/W, 8.86% at 20 mA/cm² and (0.57, 0.43) at 10 V, respectively. In addition, a deep red OLED with CIE coordinates of (0.67, 0.32) at 10 V exhibited a maximum luminous efficiency, maximum power efficiency and external quantum efficiency of 5.61 cd/A, 1.02 lm/W and 5.35% at 20 mA/cm², respectively.     

The application of single-pass heuristics for U-lines

U-lines have been adopted in many manufacturing settings as part of JIT implementation. In this paper, we examine the applicability of existing straight-line heuristics for obtaining a balance on a U-line. We modify 13 single-pass heuristics and study the effectiveness of various heuristics under different problem conditions. An extensive computational study is carried out to help identify the best heuristics. In addition, we compare recent U-line procedures with a single-pass heuristic using some literature problems. Based on a single-pass heuristic, we compare the configurations of a straight- and U-line.     

A legal cross-references taxonomy for reasoning about compliance requirements

Companies must ensure their software complies with relevant laws and regulations to avoid the risk of costly penalties, lost reputation, and brand damage resulting from non-compliance. Laws and regulations contain internal cross-references to portions of the same legal text, as well as cross-references to external legal texts. These cross-references introduce ambiguities, exceptions, as well as other challenges to regulatory compliance. Requirements engineers need guidance as to how to address cross-references in order to comply with the requirements of the law. Herein, we analyze each external cross-reference within the U.S. Health Insurance Portability and Accountability Act (HIPAA) Privacy Rule, the Gramm?CLeach?CBliley Act (GLBA), and the GLBA Financial Privacy Rule to determine whether a cross-reference either introduces a conflicting requirement, a conflicting definition, or refines an existing requirement. Herein, we propose a legal cross-reference taxonomy to aid requirements engineers in classifying cross-references as they specify compliance requirements. Analyzing cross-references enables us to address conflicting requirements that may otherwise thwart legal compliance. We identify five sets of conflicting compliance requirements and recommend strategies for resolving these conflicts.     

Introduction to the special section on Campbell’s and Rubin’s conceptualizations of causality.

Causality plays a fundamental role in scientific explanation. This introduction describes 2 target articles and 3 commentaries on 2 influential perspectives on causal inference, one developed by Donald Campbell and the other developed by Donald Rubin. One goal of this special section is to introduce Rubin’s causal model to psychologists who may be largely unfamiliar with it. Another goal is to compare Rubin’s conceptualization with Campbell’s perspective, to enrich readers’ understanding of both views. All of the authors of this special section perceive many similarities between the 2 approaches. Even so, by comparing and contrasting the 2 perspectives, the authors also believe that it is possible to strengthen both approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Morphological,Electrical, and Chemical Changes in Cyclically Contacting Polycrystalline Silicon Surfaces Coated with Perfluoroalkylsilane Self-Assembled Monolayer

The evolution of morphology, electrical properties, and chemical composition has been studied in cyclically contacting polycrystalline silicon (polysilicon) surfaces coated with perfluoroalkylsilane self-assembled monolayer (SAM). The microinstrument used is a MEMS cantilever that is repeatedly actuated out-of-plane to impact a landing pad and is then moved in-plane to enable nondestructive in situ inspection of the impacted area. Analyses show that a device with a monolayer coating exhibits signs of surface degradation after a much higher number of cycles than its uncoated counterpart. A sharp increase in contact resistance between the cantilever and landing pad is observed at ~10 billion cycles for a coated device, versus ~25 million cycles for an uncoated device. Likewise, the onset of grain fracture in the landing pad occurs at ~25 billion cycles for the SAM-coated device, versus ~3 billion cycles for its uncoated counterpart. The effectiveness of the monolayer coating diminishes after more than 100 billion contact cycles as the SAM layer is removed, and the polysilicon substrate becomes susceptible to adhesive wear.     

Tuning the electronic band structure of PCBM by electron irradiation

Tuning the electronic band structures such as band-edge position and bandgap of organic semiconductors is crucial to maximize the performance of organic photovoltaic devices. We present a simple yet effective electron irradiation approach to tune the band structure of [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM) that is the most widely used organic acceptor material. We have found that the lowest unoccupied molecular orbital (LUMO) level of PCBM up-shifts toward the vacuum energy level, while the highest occupied molecular orbital (HOMO) level down-shifts when PCBM is electron-irradiated. The shift of the HOMO and the LUMO levels increases as the irradiated electron fluence increases. Accordingly, the band-edge position and the bandgap of PCBM can be controlled by adjusting the electron fluence. Characterization of electron-irradiated PCBM reveals that the variation of the band structure is attributed to the molecular structural change of PCBM by electron irradiation.     

The effect of chemical structure of dimethyl ether (DME) on NOx formation in nonpremixed counterflow flames

To clarify the effect of chemical structure of Dimethyl ether(DME) on NOx formation in nonpremixed counterflow flame, DME flame was investigated numerically to compare the flame structures and NOx emissions with C₂H₆ and Mixed-fuel. Numerically, the governing equations were solved using the Oppdif code coupled with CHEMKIN package, and DME flames were calculated by Kaiser’s mechanism, while the C₂H₆ flames and Mixed-fuel flames were calculated by the C₃ mechanism. These mechanisms were combined with the modified Miller-Bowman mechanism for the analysis of NOx. Numerical results of nonpremixed counterflow flames show that the EI_NO of DME nonpremixed flame is low as much as 50 % of the C₂H₆ nonpremixed flame. The cause of EI_NO reduction is attributed mainly to the characteristics of partial premixed flame due to the existence of oxygen atom in DME and partly to the O-C bond in DME, instead of C-C bond in hydrocarbon fuels. This paper was presented at the 7th JSME-KSME Thermal and Fluids Engineering Conference, Sapporo, Japan, October 2008. Chang-Eon Lee received his B.S. and M.S. degrees in Mechanical Engineering from Inha University, Korea, in 1983 and 1985, respectively. Then he received his Ph.D. degree from Toyohashi National University of Technology, Japan in 1992. Dr. Lee is currently a Professor at the School of Mechanical Engineering at Inha University in Incheon, Korea. He serves as an Editor of the Journal of the Korean society of combustion and serves as an associate Editor of Transactions of the Korean society of mechanical engineers. Dr. Lee’s research interests include fluid mechanics, combustion and environmental pollution, and total energy.