224 research outputs found

    The impact of the prevailing organizational culture on the adoption of green marketing in chemical-industry companies in three Arab states in west Asia

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    The objective of this study was to investigate the impact of the prevailing organizational culture on the adoption of green marketing in chemical-industry companies in three countries: Syria, Kuwait and Jordan. The research used a survey methodology. A questionnaire was designed and administered simultaneously in the three countries using three different samples consisting of 220 respondents, 12 respondents, and 132 respondents, respectively. The questionnaires collected from the three samples were coded and analyzed. The study concluded that the organizational culture in the samples from the three countries has positive attitudes towards the adoption of green marketing. The Kuwaiti sample has the highest level of positive attitudes in comparison with the other two samples. The task-oriented culture is the dominant prevailing organizational culture in the chemical-industry companies located in Syria and Jordan, but a fulfillment-oriented culture is the dominant prevailing organizational culture in chemical-industry companies located in Kuwait. Our analysis shows that the impact of the prevailing organizational culture differs in accordance with differences in employee education level, country, and years of experience.Organizational culture; Chemical industrial companies; Green marketing; Culture

    A Hydrodynamic Study of Benzyl Alcohol Oxidation in a Micro-Packed Bed Reactor

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    The various flow regimes prevalent during gold-palladium catalyzed benzyl alcohol oxidation in a micro-packed bed reactor and their influence on reaction performance are identified. The reaction is studied in a 300μm deep x 600μm wide silicon-glass micro-structured reactor packed with 65μm catalyst particles at a temperature of 120°C, pressure of 1 bar (g), using pure oxygen and neat benzyl alcohol as the feed. Significant improvement in the conversion and selectivity to the main product, benzaldehyde, is observed with increasing gas flowrate and decreasing liquid flowrate, which coincides with a change in the flow pattern from “liquid-dominated slug” (segregated regions of liquid and gas slugs) to “gas-continuous trickle” (thin film coated catalyst particles with gas flowing through the voids). The latter flow regime results in enhanced external mass transfer due to an increase in the available interfacial area and shorter diffusional distances. Results show selectivity up to 81% at a catalyst space time of 76 gcatgalc -1.s, outperforming a conventional batch laboratory reactor

    Prediction of the characteristics of the liquid film in open inclined micro-channels

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    Falling Film Microreactor (FFMR) is one of the most important microfluidic devices for gas-liquid applications. In these devices extended specific surfaces (up to 20,000m2/m3) can be obtained while the liquid film remains stable over a wide range of gas and liquid flow rates. In an effort to propose new design correlations for these devices, in a previous work we proposed correlations for the prediction of the gas-liquid interface and the thickness of the liquid film. In this study we aim to investigate the validity of these correlations when different channel materials are used, namely brass and silicon. Velocity profiles have been also obtained by a ÎĽ-PIV system, while the thickness of the liquid film and the shape of the interface were also determined using the ÎĽ-PIV system. It was proved that the shape of the interface can be predicted with reasonable accuracy by the previously proposed correlations. Also the film thickness can be predicted with acceptable accuracy provided that some of the constants are modified according to the material of the test section

    Optimal design of experiments for the identification of kinetic models of methanol oxidation over silver catalyst

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    Partial oxidation of methanol to formaldehyde on silver catalyst represents an important industrial process due to the versatility of formaldehyde as an intermediate in chemical synthesis. The development of kinetic models is essential for a quantitative description of the changes in concentration of the chemical species involved in the process due to reaction as well as for process design and optimisation purposes. Microreactor platforms represent effective tools for the quick development of reliable kinetic models. However, the development and identification of kinetic models is strictly related to the execution of informative experiments, allowing either elucidation of the complex reaction pathways involved in the oxidation process or providing a precise estimation of the kinetic parameters for each candidate model. In this work a model-based design of experiments (MBDoE) procedure is proposed where experiments are optimally designed for both discriminating among competing models and for improving the estimation of kinetic parameters. The proposed methodology allows the most influential reaction pathways to be elucidated and provides a sequence of optimally informative experiments showing the key role of temperature in the kinetic model identification procedure

    A joint model-based experimental design approach for the identification of kinetic models in continuous flow laboratory reactors

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    Continuous flow laboratory reactors are typically used for the development of kinetic models for catalytic reactions. Sequential model-based design of experiments (MBDoE) procedures have been proposed in literature where experiments are optimally designed for discriminating amongst candidate models or for improving the estimation of kinetic parameters. However, the effectiveness of these procedures is strongly affected by the initial model uncertainty, leading to suboptimal design solutions and higher number of experiments to be executed. A joint model-based design of experiments (j-MBDoE) technique, based on multi-objective optimization, is proposed in this paper for the simultaneous solution of the dual problem of discriminating among competitive kinetic models and improving the estimation of the model parameters. The effectiveness of the proposed design methodology is tested and discussed through a simulated case study for the identification of kinetic models of methanol oxidation over silver catalyst

    Music for Thought: Examining Saudi Identities Expressed Through Music on Social Media

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    The aim of this chapter is to investigate how social media help create and diffuse popular music in Saudi Arabia and how such music questions the officially accepted identities and social practices. Social media are widely used as means of promotion among artists around the world; yet Saudi Arabia deserves special attention. This is because traditional media act much more strictly as gatekeepers in the kingdom; hence, social media offer greater possibility for circulation of popular entertainment, especially when it touches upon the questions related to the core values of the Saudi society. Such is the case of recordings by Hesham Fageeh “No woman, No drive” (2013) or the recently trending video clip “Hwages” that, both, received peak visibility online and sparked debates about women empowerment. Similarly, some videos trending online prompted a dance craze, for instance, “Barbs” showed a choreography that was subsequently copied by fans who uploaded their performances online. Dancing is a prohibition among the conservative segments of society; yet, the vastly young population of Saudi Arabia seeks entertainment.Social media in Saudi Arabia have become primordial means of communication in the kingdom with highest rates of social media participation in the Middle East and seventh rank in the world (2016). Consequently, this chapter employs a mixed-method approach in order to uncover how social media breaks the monopoly on entertainment by promoting different musical genres and encouraging social debate

    Challenges in improving the performance of eddy current testing: Review

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    Eddy current testing plays an important role in numerous industries, particularly in material coating, nuclear and oil and gas. However, the eddy current testing technique still needs to focus on the details of probe structure and its application. This paper presents an overview of eddy current testing technique and the probe structure design factors that affect the accuracy of crack detection. The first part focuses on the development of different types of eddy current testing probes and their advantages and disadvantages. A review of previous studies that examined testing samples, eddy current testing probe structures and a review of factors contributing to eddy current signals is also presented. The second part mainly comprised an in-depth discussion of the lift-off effect with particular consideration of ensuring that defects are correctly measured, and the eddy current testing probes are optimized. Finally, a comprehensive review of previous studies on the application of intelligent eddy current testing crack detection in non destructive eddy current testing is presented
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