Toward hydrogen storage material in fluorinated zirconium metal-organic framework (MOF-801): A periodic density functional theory (DFT) study of fluorination and adsorption

In this study, the structural properties and hydrogen adsorption energy of the fluorinated metal-organic framework (MOF)-801 were evaluated using density functional theory (DFT). We calculated the Zr–F bond distance to be approximately 0.225 nm, which is longer than the bond distance in zirconium fluoride compounds. Due to the electronegativity of F, this site was considered as an adsorption site for hydrogen. We determined the adsorption energy to be ?5 kcal/mol per hydrogen (H₂) molecule, which is higher than that of H₂ in pristine MOF. This value is also slightly lower than the adsorption energy in a metal-decorated MOF. The introduction of F atoms is determined to enhance the binding capacity of MOF-801.     

Tailoring the properties of cerium doped zinc oxide/reduced graphene oxide composite: Characterization,photoluminescence study,antibacterial activity

Ce doped ZnO/rGO composite materials were prepared by a one-pot hydrothermal process without any surfactant. The size, crystallography and morphology of the composite were investigated in detail by X- ray diffraction (XRD) studies, Raman spectroscopy, scanning electron microscopic (SEM), transmission electron microscopic (TEM) studies, UV–Vis spectroscopic analysis and X-ray photoelectron spectroscopic (XPS) analysis. The XRD pattern substantiates the formation of Ce doped ZnO/rGO composite revealing the wurtzite structure of ZnO. The SEM micrograph illustrates flower-like morphology for ZnO/rGO composite which coalesced further after cerium incorporation. Additionally, TEM image illustrated that ZnO hexagons were disoriented from its flower structure in Ce/ZnO/rGO composite. The XPS spectra further reaffirm the formation of cerium doped ZnO/rGO composite. The photoluminescence (PL) spectra confirms that emission occurs in the UV and visible region and several active sub-levels were observed in visible region on deconvolution, due to the incorporation of cerium. Antibacterial activity towards B. subtills and V. harveyi affirmed that the incorporation of Ce in ZnO/rGO composite leads to an improved antibacterial activity.     

Combustion Properties of Birch (Betula pendula) Black Liquors From Sulfur-Free Pulping

Sulfur-free pulping has an environmental advantage over the traditional kraft process. This article describes the combustion properties of the black liquors produced from silver birch (Betula pendula) sawdust using three different cooking processes: two sulfur-free cooks (soda-anthraquinone and oxygen-alkali), and one reference kraft cook. It also considers the corresponding black liquors from an integrated forest biorefinery, in which a hot-water pretreatment of feedstock was performed prior to pulping. With the same cooking time, the total burning times for the sulfur-free black liquors were higher (15–55%) than those for the conventional kraft black liquors. However, no significant differences were noted between the total burning times for black liquors from pretreated feedstock and those from untreated feedstock. Especially in the case of untreated feedstock, the results showed that the kraft black liquors typically swelled more (25–45%) than the sulfur-free black liquors. It was further observed that the kraft and soda-anthraquinone black liquors from the untreated feedstock swelled more than those from the pretreated feedstock, while the oxygen-alkali black liquors swelled less.     

Improved multiple secret sharing using generalized chaotic image scrambling

Multimedia Tools and Applications - This paper presents a new technique on (n,?n)-Multiple Secret Sharing (MSS) of color images. In this task, n shared images are generated from n secret...     

Redefining energy efficiency: EE 2.0

This article presents a new vision for energy efficiency ("EE 2.0″) based on the concept of energy optimization and lays the foundation for subsequent articles on EE in this special issue of Electricity Journal. Energy efficiency is key to reducing the size of the energy challenge, to accelerating the achievement of its solution, and to enhancing energy productivity, but old ideas that ignore the potential benefits of electrification and narrowly equate energy efficiency with efforts to reduce consumption of a single energy source — like electricity — need to evolve. The key to affordable decarbonization is making optimal use of low-cost, emissions-free energy sources, when and where they are available.     

Disseminating a Sun Safety Program to Zoological Parks: The Effects of Tailoring.

Previous research found that a sun safety program for visitors at 1 zoo increased sun safety behaviors. This randomized study compared the effects of tailored dissemination materials plus 2 brief follow-up phone calls (tailored group) versus generic materials (basic group) on implementation by other zoos of the previously evaluated sun safety program. Education directors of 126 zoos completed surveys several months following initial dissemination and 1 year later. During Summer 1, 40% of tailored group zoos and 24% of basic group zoos offered visitors at least 1 sun safety activity (odds ratio=2.2, 95% confidence interval=1.0-4.8). During Summer 2, these rates were 34% and 44%, respectively (ns). The pattern of findings suggests that tailoring had no incremental long-term impact and that the generic materials produced a good level of dissemination. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Longitudinal Cracking Distress on Continuously Reinforced Concrete Pavements in Illinois

The Illinois Department of Transportation (IDOT) initiated a failure investigation to determine the distress mechanisms causing premature longitudinal cracking on continuously reinforced concrete pavements (CRCP) on several Illinois interstates. The longitudinal cracking approximately followed the embedded reinforcement steel and occurred in both the driving and passing lanes. In this paper, the results from field visual surveys, coring, and petrographic analyses are reported along with a review of archival construction and material records of the distressed CRCP sections. A laboratory forensic study was also performed on several field extracted slabs. The results of the field and laboratory investigation show the cracking was not initiated by steel corrosion, deleterious reactions in the concrete materials, or an inadequate structural design. Rather, the cracking is related to settlement of the steel bars in the concrete. Settlement cracking is conventionally thought to occur only in concrete slabs and decks with plastic (high slump) concrete and small values of bar cover depth, while the studied CRCP sections have large values of cover depth and were cast with stiff (low slump) concrete. The settlement was likely caused by the relative settlement of heavy steel bars (22?mm diameter) within the lower density concrete during the original CRCP construction. The technique of placing the steel bars in the fresh concrete (called tube-feeding) further contributed to the development of this distress, and this practice is no longer employed by IDOT.     

Waste paper sludge as a potential biomass for bio-ethanol production

This review describes the utilization of paper sludge (PS), which is waste from the pulp and paper industry. Its advantages make PS the cellulosic biomass with the most potential for bio-refinery research and applicable for industrial scale. Some of the grain based biofuels and chemicals have already been in commercial operation, including fuel ethanol or biochemical products. Unfortunately, research and application of PS are yet in their infancy and suffer from large scale because of low productivity. Reviewing the many researches that are working at the utilization of PS for bio-refineries could encourage the utilization of PS from laboratory research to be applied in industry. For this reason, PS usage as industrial raw material will be effective in solving the environmental problems caused by PS with clean technology. In addition, its conversion to bio-ethanol could offer an alternative solution to the energy crisis from fossil fuel. Two methods of PS utilization as raw material for bio-ethanol production are introduced. The simultaneous saccharification and fermentation (SSF) using cellulase produced by A. cellulolyticus and thermotolerant S. cerevisiae TJ14 gave ethanol yield 0.208 (g ethanol/g PS organic material) or 0.051 (g ethanol/g PS). One pot bioethanol production as a modified consolidated biomass processing (CBP) technology gave ethanol yield 0.19 (g ethanol/g Solka floc) and is considered to be the practical CBP technology for its minimizing process.