Study mass transfer of Cd, Hg, As, DDT and chlordane through adsorption onto granular activated carbon

The kinetic theory of liquid indicates that diffusion coefficient for the dilute liquid at ordinary pressure is essentially independent of mixture composition. Mass transfer is important in separation and adsorption process. However, diffusion may also be caused by other features. Because of the complex nature of mass diffusion, the diffusion coefficients are usually determined experimentally. The mass transfer resistance controls the kinetic adsorption rate, but there is only limited understanding of the adsorption of a solute onto porous material from surface water. Thus, this study was conducted to further enhance the understanding of the mass transfer and adsorption processes of micropollutants. The objectives of this study are to analyze the difference, examine the adsoprtion diffusion of mass transfer and evaluate the variation of total, internal and external mass transfer. This study also used the transformed equation to analyze the rate of adsorption during adsorption process onto different GACs. Five (5) micropollutants namely Hg, Cd, As, DDT and chlordane have been chosen to be adsorbed onto three (3) granular activated carbon which are SIG (shell industrial grade), SAG (shell analytical grade) and BAG (bitumen analytical grade). The micropollutants (Hg, Cd, As, DDT and chlordane) were prepared using standard stock solution in deionized water. Adsorption of pollutants onto SIG, SAG, and BAG were started at different percentages of outflow. Although the samples were taken at the same time, the outcome showed that a significant competition between adsorbates and adsorbents. From the analysis, SIG and SAG displayed excellent performance in adsorbing inorganic micropollutants while BAG for organic micropollutants. Before adsorption takes place, the morphology of the SAG indicated pore abundance compared to SIG and BAG. BAG pores are more structured than SIG and SAG. After adsorption occurs, more of the organic micropollutants are being adsorbed onto BAG and SAG. Meanwhile, SIG proved to be the best adsorbent for inorganic micropollutants. It takes 72 hours for Hg vi and As to saturate SIG whilst Cd take a longer time of 80 hours. SAG was also a good adsorbent for organic elements, with DDT taking 52 hours and chlordane taking 48 hours to be adsorbed. The [KLa]f value for the adsorption of Hg onto SIG was significant and the [KLa]d value for the adsorption of Hg onto SIG was higher onto SAG and BAG. The value of [KLa]f for SIG at 6% outflow was 0.6862 h-1, with values of [KLa]d at -0.4142 h-1 and [KLa]g at 0.2721 h-1, while for the adsorption of Cd it was shown that the [KLa]f values for the adsorption of Cd onto BAG was the most significant and the [KLa]d values for the adsorption of Cd onto SIG was higher than SAG and BAG at 2% outflow, with values of 0.7044 h-1, [KLa]d at -0.3687 h-1, and [KLa]g at 0.3356 h-1. In contrast, for As the [KLa]f for the adsorption of As onto BAG at 4% outflow was 0.6722 h-1 and [KLa]g was 0.3103 h-1. For DDT, the [KLa]f value of DDT for BAG at 0.5% outflow was 1.6662 h-1, [KLa]d was -1.2702 h-1 and [KLa]g was 0.3959 h-1. In the case of DDT, the value of [KLa]f for the adsorption of chlordane onto BAG at 2% outflow was 0.7330 h-1 and [KLa]d was started to activate the adsorption -0.5567 h-1. [KLa]g at 2% outflow was 0.1763 h-1. From these values we can conclude that for the adsorption of inorganic substances, SIG proved to be the best, while for organic substances BAG is the best adsorbent

Perkaitan di antara status sosioekonomi keluarga dengan Pencapaian akademik pelajar aliran teknikal

Selain daripada mengendalikan fungsi pendidikan, sekolah juga diberikan peranan bagi menyediakan tenaga mahir untuk memenuhi keperluan ekonomi negara. Sekolah aliran teknikal dilihat sebagai satu institusi khusus yang memainkan peranan tersebut. Namun begitu, terdapat pelbagai faktor yang boleh mempengaruhi pencapaian pelajar aliran teknikal ini. Tahap sosioekonomi keluarga telah dikenalpasti antara faktor yang boleh mempengaruhi pencapaian pelajar. Kajian ini dilakukan untuk mendapatkan perkaitan di antara tahap sosioekonomi keluarga seperti tahap pendidikan bapa, jumlah pendapatan dan saiz keluarga terhadap pencapaian akademik pelajar. Sampel kajian ini ialah pelajar-pelajar tingkatan 4 dan 5 yang menetap di asrama Sekolah Menengah Teknik Kuala Terengganu. Pelajar ini dipilih kerana mereka mendapat kemudahan dan persekitaran pembelajaran yang sama. Seramai 80 orang pelajar dalam jurusan teknikal dipilih secara rawak mudah. Keputusan kajian mendapati bahawa hanya saiz keluarga mempunyai korelasi yang tinggi berbanding tahap pencapaian akademik bapa dan jumlah pendapatan keluarga. Ini menunjukkan bahawa faktor saiz keluarga memberikan impak secara langsung kepada pencapaian pelajar walaupun mereka menetap di asrama yang menyediakan suasana dan kemudahan yang sama

The role of Zionist movement towards the creation of the state of Israel (Peranan pergerakan zionist terhadap pembentukan negara Israel)

The problem of Palestine has been a subject of much debate not only among scholars but also involved world superpowers as well. As this conflict rages on, there is a need to look at the root cause of the problem which one could argue that, among others, was caused by the ambitions of Zionist Movement. This paper examines the emergence of Zionist Movement and its role in establishing the State of Israel by confiscating Palestinians‟ territory and land. Zionist controls over the territory has resulted in the expulsion of Palestinians from their homeland. This study was conducted as a library research with textual analysis on the sources of Palestine historiography. The result shows that the Zionist Movement had lobbied the world superpowers, especially Britain and United States of America, until they supported the movement and resulting in the creation of the State of Israel on the Palestinian land

Application Of Dynamic Correlation Technique And Model Updating On Truck Chassis

Truck chassis is a major component in a vehicle system. It is often identified for refinement in order to develop vehicles with reduced cost and weight. Nowadays the process of chassis design in the automotive industry has been significantly refined with the high capabilities of advanced computer aided design and engineering tools,. The application of FEA such as structural modification and optimization is used to reduce component complexity, weight and subsequently cost. Because the level of model complexity can be high, the opportunity for error can also be high. For this reason, some form of model verification is needed before design decisions made in the FEA environment can be implemented in production. This paper looks into the application of dynamic correlation techniques for verification of the FEA models of truck chassis. The dynamic characteristics of truck chassis such as the natural frequency and mode shape were determined using finite element method. Experimental modal analysis was carried out to validate the FE models. Initial results from both analysis show that the truck chassis experienced 1st torsion mode for 1st natural frequency, 1st bending mode for 2nd natural frequency, 2nd torsion mode for 3rd natural frequency and 2nd bending mode for 4th natural frequency. However there is a small discrepancy in terms of frequency. Thus, the model updating of truck chassis model was done by adjusting the selective properties such as Modulus Young and Poisson ratio in order to get better agreement in the natural frequency between both analysis. Finally, the modifications of the updated FE truck chassis model was suggested such as by considering adding the stiffener. The purpose is to reduce the vibration as well as to improve the strength of the truck chassis

Laser-induced breakdown spectroscopy experimentation and applications

This is an era of rapid production and fast growth. Reliable and fast analytical testing techniques are an essential part of manufacturing industries and testing and certifying authorities. Laser-Induced Breakdown Spectroscopy (LIBS) is one of the highly potential techniques to compete in this competitive arena for rapid elemental analysis which can be further used for real-time composition monitoring in the production line, post-production inspection, scrap sorting and even for classification of biological samples. In addition, remote and stand-off modes of operation increase the application potential of LIBS by many folds. It can be deployed in physically inaccessible or potentially unsafe areas. Compact LIBS systems have made its portability possible which implies ease of in-situ deployment

Growth parameters of InAs/GaAs quantum dots grown by MOVPE

Quantum dots are zero dimensional structures and therefore have superior transport and optical properties compared to either 2-dimensional or 3-dimensional structures. Quantum dots show promise for use in diode lasers, amplifiers, and biological sensors. They are also vigorously researched for use in solid-state quantum computing. Indium arsenide quantum dots are currently studied for their use in the photoelectronic and semiconductor fields. In our research, Indium Arsenide (InAs) quantum dots are grown on Gallium Arsenide (GaAs) substrate using Metal Organic Vapor Phase Epitaxy (MOVPE) in the Stranski-Krastanov Growth mode. Several parameters influence the growth of InAs quantum dots greatly. We will be describing these growth parameters, which we have identified in our current growth attempts. We are currently trying to achieve device quality InAs/GaAs quantum dots by varying these parameters we have identified. These growth parameters include the V/III ratio of both InAs and GaAs, In/As growth temperature, and quantum dot growth time. By carefully fine tuning the parameters above, we will be able to grow device quality quantum dots. Deviations from the optimized value will result in either no formation of quantum dots, or the formation of large islands which are particularly susceptible to dislocations. The effects of differing growth parameters are observed by using an Atomic Force Microscope (AFM) located at Faculty of Science, UTM. The MOVPE is located at Ibn Sina Institute for Fundamental Science Studies, UTM

The mediating effect of enterprise risk management practices on organizational attributes and organizational performance / Azreen Roslan

Risk is inherent in all organizations, but if inefficiently managed will affect the confidence and expectations of the stakeholders. The development of an enterprise risk management (ERM) program enables organizations to manage corporate risks in a holistic manner as opposed to the silo-based perspective in traditional risk management frameworks. ERM is a best practice technique to evaluate and manage risks in an integrated manner to cater to the new economic reality. Further, ERM is a management tool to assist top management to make informed decisions. Past studies have established positive effects of ERM practices, as organizations are better prepared to manage their feasible threats in a holistic and integrated manner. In fact, there are general consensuses of researchers that organizations practicing ERM are found to perform better due to the fact that such organizations are able to ensure that the total risks facing their organization are well managed. More specifically, their current, future and emerging risks are identified and controlled to allow the organization to achieve their strategic objectives. For this to happen, top management support is crucial to drive ERM and ensure better organizational performance. However, evidence pertaining to this is still scarce. As such, this research aims to provide a better understanding of the influence of organizational attributes on the extent of ERM practices towards organizational performance. A research model is developed to examine and evaluate the attributes of ERM practices and its influence on organizational performance. In addition, two underpinning theories namely Agency theory and Contingency theory are used to justify these relationships. The existing empirical evidence with regard to the risk management activities of nonfinancial organizations were collected, in order to gain insight into the extent of ERM practices. A questionnaire survey technique is employed to collect data from the public listed of non financial companies. 102 useable responses were received and further analyzed using the appropriate statistical procedures. The research model was then tested using the partial least squares (PLS) technique. Smart PLS 2.0M3 was used to validate the research model and test the proposed research hypotheses. The empirical results of this research lead to several significant findings. This study confirms that ERM practices positively influences organizational performance. Under the construct of organizational attributes, organizational structure and role clarity are found to have significant positive relationship with the extent of ERM practices. However, the result does not support hypothesized relationships between board composition (board independence and role separation) and the extent ERM practices. In addition, findings showed that the extent of ERM practices mediates the relationship between organizational structure and role clarity with organizational performance. However, the findings showed that the extent of ERM practices does not mediate the relationship between board composition and organizational performance. Theoretically, this study provides further insights on the attributes and outcomes of the extent of ERM practices within Malaysia public listed of non financial companies' context. Methodological and managerial implications were discussed and several possible avenues for future research were identified and proposed. In short, the findings of this study shed new light to the existing ERM literature and provide better assurance to the industry practitioners on the significance of ERM practices in the organization