Halogenation of SiC for band-gap engineering and excitonic functionalization

The optical excitation spectra and excitonic resonances are investigated in systematically functionalized SiC with Fluorine and/or Chlorine utilizing density functional theory in combination with many-body perturbation theory. The latter is required for a realistic description of the energy band-gaps as well as for the theoretical realization of excitons. Structural, electronic and optical properties are scrutinized and show the high stability of the predicted two-dimensional materials. Their realization in laboratory is thus possible. Huge band-gaps of the order of 4 eV are found in the so-called GW approximation, with the occurrence of bright excitons, optically active in the four investigated materials. Their binding energies vary from 0.9 eV to 1.75 eV depending on the decoration choice and in one case, a dark exciton is foreseen to exist in the fully chlorinated SiC. The wide variety of opto-electronic properties suggest halogenated SiC as interesting materials with potential not only for solar cell applications, anti-reflection coatings or high-reflective systems but also for a possible realization of excitonic Bose-Einstein condensation

Customers' need for uniqueness theory versus brand congruence theory: the impact on satisfaction with social network sites

Social media brands may experience a lack of competitiveness and attraction due to the silent negative increase of customers' need for uniqueness (NFU). This is the result of a tension between the theory of brand congruence, that most brands endeavor to establish with their customers, and the theory of consumers' NFU, that many consumers aim to fulfill, that has not been previously examined. Whilst the theory of brand congruence states that consumers have a favorable attitude towards brands that greatly match their self-concept (brand similarity), the theory of uniqueness, when brand similarity is shared with others, generates avoidance of similarities with others, leading to a reduction in engagement and satisfaction. Social media platforms including Facebook are at risk from customers' NFU which significantly reduces users' satisfaction, hence reducing the attractiveness and usage of Facebook. To examine this, the paper identifies the paradox of similarity in relation to both theories and examines the relationship between consumers' socialization within Social Network Sites (SNSs), brand similarity, consumers' need for uniqueness, and consumers' satisfaction with the SNS. The conceptual model was tested using data from 341 consumers in the US. The findings show that whilst satisfaction with the SNS is enhanced by brand similarity and friend liking, it is undermined by customers' need for uniqueness. Implications for online brand communities and SNSs (Facebook) are discussed and guidance for future research is provided

A framing analysis of Al-Jazeera\u27s coverage of the Palestinian Fatah-Hamas conflict.

By utilizing both framing and descriptive analysis, this study examined how an Arab media outlet, Al-Jazeera, with an increasingly global reach framed the Palestinian-Palestinian conflict. The 2006 Palestinian legislative elections and the 2007 fall-of-Gaza under the control of Hamas were two critical Palestinian events that warranted an examination of how coverage of these two periods was framed. Thirty frames were found in Al-Jazeera\u27s coverage of the two mentioned critical events. These frames were categorized into seven major sets of frames. The civil war and the politics\u27 sets of frames dominated Al-Jazeera\u27s coverage in the fall-of-Gaza period, and the elections and politics\u27 sets of frames dominated Al-Jazeera\u27s coverage in the elections\u27 period. The study tested the tone of the coverage to determine whether there was favoritism shown to Hamas. Overall, the channel\u27s presentation of the news related to Palestinian coverage was neutral with significant favoritism to Hamas especially in the fall-of-Gaza period. Another finding of this study was that Al-Jazeera\u27s coverage of both time periods was heavily episodic. Two compositional elements, camera angle and proximity of subject to viewer, were analyzed for this study, and Al-Jazeera conveyed a sense of credibility and objectivity by using images that act as records of events. Therefore, visual elements were not used as framing devices that would result in favoritism to Hamas

Disabled Friendly Facility between Feasibility and Legality

Most hotels in Lebanon, built before 2011, do not provide access to disabled persons in light of 220/2000 law. This is due to: 1/ a misconception that a Disabled Friendly Facility (DFF) would be on behalf of hotel guests’ satisfaction and consequently, would reduce hotel’s popularity and revenue; 2/ a fear that the unforeseen demand for DFFs will be offset by expenses and, in best-case scenarios, would not generate enough profits to pay back initial investments. In brief, hotel-business investors are not sure about the convenience of a DFF and about the number of DFFs to provide in light of 7194/2011law. The objective of this paper is, on the first hand, to demonstrate the financial feasibility and the economic convenience of a DFF and, on the other hand, to test its impact on the satisfaction of hotel guests. In other terms, on the popularity of the hotel

Utilization of Lightweight Tetrapod Aggregate Produced from a High Calcium Fly Ash in Civil Engineering Applications

Due to the increasing volumes of fly ash production in some countries that depend on coal for running their thermal power plants, new utilization areas must be found. One of these areas is to utilize large volume applications such as the production of special shape aggregate (tetrapod) to be used in different geotechnical applications and highway construction. This is beneficial in solving the disposal problem of fly ash as well as making economical use of a mineral resource. To achieve these goals, fly ash was utilized in producing tetrapod shape lightweight aggregate by pressing into a specially designed mold. Pre to the production of tetrapods, regular lightweight fly ash aggregates were produced, cured and tested. Test results on the regular lightweight fly ash aggregates were implemented in the production of tetrapods. Optimization of lime content showed that five per cent by weight lime addition to fly ash had the best performance. Tests were conducted on the cured tetrapods in order to determine their mechanical and physical properties. Absorption and other properties were improved by surface treatment with water glass and heating

Effect of Superpave Short-Term Aging on Binder and Asphalt Mixture Rheology

This study aimed to evaluate the effect of Superpave short term aging period length and type of additive used in modifying the asphalt binder on the creep behavior of asphalt binder and asphalt mix. Hot-mix asphalt (HMA) specimens were prepared at optimum asphalt content using unmodified asphalt, or asphalt with 4% by weight of SBS or PE. The Universal Testing Machine was used to conduct dynamic creep tests. Tests results indicated that the effect of extending the aging period on creep deformation is highly dependent on type of additive used in preparing the asphalt mix. Extending the aging period more than three hours caused insignificant effect of creep behavior of control asphalt mixes. On the other hand, extending the aging period more than one hour caused insignificant effect of creep behavior of asphalt mixes prepared using SBS additive. While for mixes prepared using PE, the creep deformation continues to decrease as aging period increase

Spline approximation for system of two third order ordinary differential equations, II

Not available

CHARGE-TRANSFER COMPLEXES OF CHLORPHENOXAMINE HYDROCHLORIDE WITH CHLORANILIC ACID, 2,3-DICHLORO-5,6-DICYANO-1,4-BENZOQUINONE AND 7,7,8,8-TETRACYANOQUINODIMETHANE AS π-ACCEPTORS

Objective: To develop simplified, accurate and precise visible spectrophotometric strategies for the assay of chlorphenoxamine hydrochloride (CPX) in pure drug and in its pharmaceutical preparations. Methods: The described methods depended on the formation of charge-transfer (CT) complexes of intense color between CPX as donor with three π-acceptors, chloranilic acid (CLA), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and 7,7,8,8-tetracyanoquinodimethane (TCNQ) and the colored reaction products were estimated spectrophotometrically at 520 nm, 460 nm and 840 nm for CLA, DDQ, and TCNQ complexes, individually. All the optimum conditions were established. The proposed methods were validated in term of linearity, limit of detection as per the international conference on harmonization guidelines ICH Q2 (R1). Results: The complexes obeyed Beer’s law in the concentration range of 16-144, 6-54 and 4-76 μg/mlwith molar absorptivity at 0.30×104, 0.68×104 and 0.58×104 l/mol/cm for CLA, DDQ, and TCNQ, individually. According to Benesi-Hildebrand plots, the association constants and changes of standard free energy were determined. 1:1 was the ratio of composition of the formed CT-complex. Conclusion: The obtained results revealed that the developed method can be applied successfully for the determination of CPX in drug formulations samples with good accuracy and precision

GreenSTEM’s microbe technology is an efficient, effective, and affordable way to clean up fuel and chemical spills

Non-Peer ReviewedPetroleum hydrocarbons are used as fuel and for chemical synthesis. If spilled, fuels and chemicals poison our soil and water, causing local environmental disasters. Bioremediation uses organisms to clean up (remediate) pollutants. We have isolated and characterized microbe strains from contaminated sites, and use them to remediate contaminated sites elsewhere. We identify our strains using their DNA sequences and their appearance. Some microbes, called fungal endophytes, form symbioses, in other words metabolic partnerships between a plant and a fungus. These symbioses have been shown to stimulate plant growth and root formation, even on contaminated soil. Surprisingly, some of our other microbes can degrade hydrocarbons underground, without plants. GreenSTEM has powerful technology: we use native microbes to degrade hydrocarbons and chemicals as they grow on the contaminants as food. Based on our progress to date with fuels and other chemicals, we anticipate isolating new strains specific for other intractable toxins

Evaluation of Road Pavement Maintenance by Contract in Jordan

In this research, road pavement maintenance by contract in Jordan was investigated. For this purpose, a subjective procedure (the Present Serviceability Rating (PSR)) was used to evaluate pavement serviceability. Three major highways (Jarash-Amman highway, Naour-Dead Sea highway and Zarqa-Syrian borders highway) that were maintained by contract were selected. The developed data base included information on pavement characteristics, traffic type and volume and routine maintenance cost. The effect of maintenance cost on pavement serviceability was estimated by developing a statistical relationship between maintenance cost and pavement serviceability rating before and after maintenance. The results showed that the pavement serviceability of Jarash-Amman highway and Naour-Dead Sea highway was adversely affected after applying maintenance by contract. The pavement serviceability of Zarqa-Syrian borders highway was slightly improved after applying maintenance by contract, but the improvement was not up to expectations. It is believed that the reasons for such results are a combination of the contractor’s poor experience and qualification and the timing of maintenance where the pavement was left without maintenance until it reached fair or poor condition