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Current state of e-services in Saudi Arabia: the case of intermediaries in facilitating government services in Madinah city
The government of Madinah has launched âKhdamatecâ electronic Offices (e-Offices) concept under their national electronic Government (e-Government) modernisation agenda to facilitate service delivery to citizens and seamless interaction to communicate their needs. By offering e-Offices around the government departments, Madinah government hopes to increase accessibility of e-Government services and make steps forward to electronic age, encourage Medina' citizens to participate and use e-Services and bridging digital divide. However, the empirical findings illustrate that the adoption and diffusion of the e-Office concept and e-Government in the wider context at a lethargic pace. This paper highlights some of the challenges faced by the Madinah city in implementing the e-Office concept and e-Government
SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF FUSED ISOXAZOLE DERIVATIVES USING GRINDING METHOD
Objective: A facile and efficient synthesis of new pyrazoloisoxazole, isoxazolopyridine and isoxazolopyrimidine derivatives is discribed through interaction of isoxazolone derivative with different nitrogen nucleophiles. Nine of the newly synthesized compounds were tested for antibacterial activities.
Methods: Interaction of isoxazolone derivative with different nitrogen nucleophiles under grinding conditions.
Results: New pyrazoloisoxazole, isoxazolopyridine and isoxazolopyrimidine derivatives were synthesized and the structures of the prepared compounds were elucidated from spectral data.
Conclusion: 4-(4-Chlorobenzylidene)-3-phenylisoxazol-5(4H)-one was utilized as key intermediate for the synthesis of some new heterocycles, namely pyrazoloisoxazole, isoxazolopyridine and isoxazolopyrimidine derivatives under grinding conditions. Most of the newly synthesized products revealed moderate activity against Gram-negative and Gram-positive bacteria
Some Polysorbate Compounds as Corrosion Inhibitors for Carbon Steel in Hydrochloric Acid
Some commercial non-ionic surfactants polysorbate, namely, polysorbate 80, polysorbate 40 and polysorbate 20, were tested as inhibitors for corrosion of C-steel in 2.0M HCl solution using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy techniques. It was found that all the three used compounds act as inhibitors for acid corrosion of C-steel. The inhibition efficiencies obtained by the three techniques were almost the same, and increase with increasing the hydrocarbon chain length and the surfactant concentration. The polarization studies show that these compounds act as mixed inhibitors. The inhibition action of these surfactants can be explained by their ability to adsorb on the metal surface making a barrier to mass and charge transfer.ĂÂ It was found that the adsorption of these surfactants follows Langmuir adsorption isotherm. The negative values ofĂÂ adsorption free energy indicating that the adsorption process is spontaneous and increases, for different surfactants, in the same direction as inhibition efficiency
A PMSM current controller system on FPGA platform
Permanent magnet synchronous motor (PMSM) has gained more interest recently in industrial applications. Digital hardware solutions such as field programmable gate arrays (FPGAs) are the most preferred methods for controlling PMSM drivers. This paper presents an implementation of a current control system for PMSM based on FPGA. Encoder-based speed and position detection method has been used in proposed hardware. The whole system has been modeled and simulated in system level using MATLAB/SIMULINK. Hardware architecture for all computational blocks is implemented using Verilog HDL. The hardware architecture has been successfully synthesized and implemented on Altera Cyclone II FPGA. Proposed system architecture and computational blocks are described and system level and RTL simulation results are presented. Simulation results show that the total computation cycle time of implemented system on Altera Cyclone II FPGA is 456ns.Keywords: PMSM, FPGA, Incremental encoder, CORDIC, Hysteresis Current Control
Examining the influence of intermediaries in facilitating e-government adoption: an empirical investigation
YesThe adoption and diffusion of electronic government is often impeded by many social and
individual factors relating to citizens. In this respect, intermediaries have emerged as a new model for
delivering e-government services to overcome such obstacles. This study aims to examine the role of
intermediaries in facilitating e-government adoption and diffusion using a survey based empirical
study of 502 participants in Madinah City in Saudi Arabia. An extended UTAUT model is used as the
theoretical basis utlising trust in the Internet and Intermediaries. The results of this study show that there are significant relationships among the factors that influence intention to use e-government, namely, performance expectancy, effort expectancy, and trust of intermediary. In addition, the findings show that there is a significant relationship between facilitating conditions and usage behaviour proving that intermediaries can influence adoption of e-government services
On the Burr XII-Power Cauchy Distribution: Properties and Applications
We propose a new four-parameter lifetime model with flexible hazard rate called the Burr XII Power Cauchy (BXII-PC) distribution. We derive the BXII-PC distribution via (i) the T-X family technique and (ii) nexus between the exponential and gamma variables. The new proposed distribution is flexible as it has famous sub-models such as Burr XII-half Cauchy, Lomax-power Cauchy, Lomax-half Cauchy, Log-logistic-power Cauchy, log-logistic-half Cauchy. The failure rate function for the BXII-PC distribution is flexible as it can accommodate various shapes such as the modified bathtub, inverted bathtub, increasing, decreasing; increasing-decreasing and decreasing-increasing-decreasing. Its density function can take shapes such as exponential, J, reverse-J, left-skewed, right-skewed and symmetrical. To illustrate the importance of the BXII-PC distribution, we establish various mathematical properties such as random number generator, moments, inequality measures, reliability measures and characterization. Six estimation methods are used to estimate the unknown parameters of the proposed distribution. We perform a simulation study on the basis of the graphical results to demonstrate the performance of the maximum likelihood, maximum product spacings, least squares, weighted least squares, Cramer-von Mises and Anderson-Darling estimators of the parameters of the BXII-PC distribution. We consider an application to a real data set to prove empirically the potentiality of the proposed model
Synthesis of New Azoles and Azolopyrimidines Incorporating Morpholine Moiety as Potent Anti-Tumor Agents
A new series of morpholinyl-chalcones 2aâd was prepared by reaction of 2-oxo-N,4-diarylbut-3-enehydrazonoyl chlorides 1aâd with morpholine. These chalcones were used as a building block for constructing pyrazoles 3aâd and 3,4-dihydropyrimidine-2(1H)-thione 6 via their reaction with phenylhydrazine and thiourea, respectively. Moreover, a new series of azolopyrimidine derivatives 11a,b, 15, 17, 19, and 21 incorporating morpholine moiety were synthesized by reaction of 1-morpholino-4-phenyl-1-(2-phenylhydrazono)but-3-en-2-one (2a) with a number of heterocyclic amines in the presence of a catalytic amount of acetic acid. The assigned structures for all the newly synthesized compounds were confirmed on the basis of elemental analyses and spectral data and the mechanisms of their formation were also discussed. All the synthesized compounds were tested for in vitro activities against two antitumor cell lines, human lung cancer (A-549) and human hepatocellular carcinoma (HepG-2) compared with the employed standard antitumor drug (cisplatin) and the results revealed that compounds 6, 8c and 17 have promising activities compared with cisplatin.
This work is licensed under a Creative Commons Attribution 4.0 International License
Effect of thermal and ultraviolet treatments on the stability of antioxidant compounds in single strength pineapple juice throughout refrigerated storage
Thermal treatment is commonly applied in juice manufacturing as a method to pasteurize juices. However the heat may deteriorate some of the essential compounds in the juice, especially heat-sensitive antioxidants. Therefore non-thermal treatment such as ultraviolet (UV) ray has been proposed as an alternative for pasteurization. The objective of this study was to compare the effect of thermal and UV treatments on the content of antioxidants (phenolic acids, flavonoids, carotenoids, ascorbic acids) and antioxidant capacity of single strength pineapple juice. The antioxidants stability of juices throughout 14 days of refrigerated storage was also studied. Ultraviolet treatment shows higher ascorbic acid content after treatment as compared to thermally treated single strength pineapple juice. Storage time affected the studied antioxidants, where UV treatment provided better stability to ascorbic acid content while thermal treatment provided better stability to flavonoids and carotenoids
Efficient, Recyclable, and Heterogeneous Base Nanocatalyst for Thiazoles with a Chitosan-Capped Calcium Oxide Nanocomposite
Calcium oxide (CaO) nanoparticles have recently gained much interest in recent research due to their remarkable catalytic activity in various chemical transformations. In this article, a chitosan calcium oxide nanocomposite was created by the solution casting method under microwave irradiation. The microwave power and heating time were adjusted to 400 watts for 3 min. As it suppresses particle aggregation, the chitosan (CS) biopolymer acted as a metal oxide stabilizer. In this study, we aimed to synthesize, characterize, and investigate the catalytic potency of chitosanâcalcium oxide hybrid nanocomposites in several organic transformations. The produced CSâCaO nanocomposite was analyzed by applying different analytical techniques, including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM). In addition, the calcium content of the nanocomposite film was measured using energy-dispersive X-ray spectroscopy (EDS). Fortunately, the CSâCaO nanocomposite (15 wt%) was demonstrated to be a good heterogeneous base promoter for high-yield thiazole production. Various reaction factors were studied to maximize the conditions of the catalytic technique. High reaction yields, fast reaction times, and mild reaction conditions are all advantages of the used protocol, as is the reusability of the catalyst; it was reused multiple times without a significant loss of potency
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