Characterization of beach sedimentary environments in the Batinah Region, Oman.

In this study, 252 surface sediment samples were collected for sand properties from three sites on the North Batinah coast: Harmul, North of Sohar industrial area, Majees South of Sohar industrial area and Zafaran 9 km South of Majees. Sampling was conducted in four occasions: November 2005, February 2006, June 2006 and November 2006. Almost, 52% of all samples were unimodal, 32% were bimodal and 16% were polymodal. June 2006 samples had a higher particle density than November 2006 samples. This is most probably due to rework and suspension, which lead to removal of light particles from the upper layer of the beach and high density particles to be concentrated in the bottom layer in June 2006 and deposition of light fraction of lower density in November 2006. Only Harmul samples had a significant difference between June 2006 samples and November 2006 samples in bulk density. The difference between the two sets in percentage water by volume was significant in Harmul and Zafaran but not in Majees. All sites showed significant difference between the two sets in percentage of air filled porosity and percentage of saturation. However, the sand pattern was the same in the three sites

Comparison of monsoon variations over groundwater hydrochemistry changes in small Tropical Island and its repercussion on quality

Study on the spatial and temporal distribution of groundwater hydrochemistry in the small tropical islands is important as their insular character may expose the groundwater aquifer to too many sources of pollution, especially salinization. A total of 216 groundwater samples were collected from the monitoring boreholes during two different monsoon seasons; pre- and post-monsoon. As overall, data of groundwater concentration illustrated a trend of Ca > Na > Mg > K and HCO3 > Cl > SO4 dominations with the major finding of two different groundwater types. Pre-monsoon reported Na-HCO3 and Ca-HCO3 types while post-monsoon were only dominated by the Ca-HCO3 type. The statistical analysis shows the in situ parameters (Temp, pH, EC, Salinity, DO, TDS and Eh) and major ions (Ca, Mg, Na, K, HCO3, Cl and SO4) were strongly correlated with the monsoon changes (p < 0.01). From the analysis, its reveals that the seasonal changes have significantly affects the groundwater composition. While, the analytical calculations of the ionic ratio (Na vs. Cl; Cl/HCO3 vs. Cl; Ca + Mg vs. SO4 + HCO3) describes the groundwater is influenced by the cation exchanges processes, simple mixing and water–rock interaction. Saturation indices of carbonate minerals shows strong correlationship (p < 0.01) with Ca constituent indicating solubility on minerals, which led to dissolution or precipitation condition of water. Results of present study contribute to a better understanding of a complex groundwater system and the hydrochemical processes related

Anti-inflammatory and analgesic effects of ketoprofen in palm oil esters nanoemulsion

Ketoprofen is a potent non-steroidal anti-inflammatory drug has been used in the treatment of various kinds of pains, inflammation and arthritis. However, oral administration of ketoprofen produces serious gastrointestinal adverse effects. One of the promising methods to overcome these adverse effects is to administer the drug through the skin. The aim of the present work is to evaluate the anti-inflammatory and analgesic effects from topically applied ketoprofen entrapped palm oil esters (POEs) based nanoemulsion and to compare with market ketoprofen product, Fastum® gel. The novelty of this study is, use of POEs for the oil phase of nanoemulsion. The anti-inflammatory and analgesic studies were performed on rats by carrageenan-induced rat hind paw edema test and carrageenan-induced hyperalgesia pain threshold test to compare the ketoprofen entrapped POEs based nanoemulsion formulation and market formulation. Results indicated that there are no significant different between ketoprofen entrapped POEs nanoemulsion and market formulation in carrageenan-induced rat hind paw edema study and carrageenan-induced hyperalgesia pain threshold study. However, it shows a significant different between POEs nanoemulsion formulation and control group in these studies at p<0.05. From these results it was concluded that the developed nanoemulsion have great potential for topical application of ketoprofen

Flapping membrane wing: a prediction towards inter-domain flight

The purpose of this research is to gain initial knowledge and to predict the sustainability of an all-weather Micro-Aerial-Vehicle (MAV). The observed parameters are: the maximum coefficient of lift, CL and the changes in CL after impact, the fluctuation of CL upon entering simulated rain environment, and length of stability recovery in terms of time and flapping cycle, t and t/T, at flapping frequencies of 8, 16, and 24 Hz, at t/T = 3/8 and 7/8. At 24 Hz, the increase in peak CL value after impact of entering rain environment is 0.59. The average fluctuations in CL occurred when entering the rain environment are 410.263. The stability recovery time recorded is 0.006 seconds. Small birds (especially hummingbirds) have a very high flapping frequency that enables them to efficiently withstand external disturbances caused by nature and to instantly adapt to new environments

Engineering Ultrasound Contrast Agents for Increased Stability and Nonlinearity

There has been increasing interest in the use of microbubbles as contrast agents in various diagnostic and therapeutic applications of biomedical ultrasound. New techniques have been developed which rely upon nonlinear scattering of acoustic waves by contrast agents undergoing volumetric oscillations upon exposure to ultrasound. The degree of nonlinearity can be improved by increasing the amplitude of the insonation pressure. This may, however, increase the risk of destroying the contrast agent and produce undesirable side effects either through inducing shear stress around them, or by undergoing inertial cavitation. The latter phenomenon is associated with high temperature and extreme pressures and can potentially damage the tissue surrounding the bubble. A further problem is the change in contrast agent size due to dissolution which is an important factor in determining their response to ultrasound. A proposed solution to these issues is to deposit solid nanoparticles on the outer surface of the microbubbles to form a semi-solid shell upon reaching a certain surface density. As the bubbles undergo volumetric oscillations, the particles offer resistance when bubbles contract but not during expansion. The asymmetry of oscillations is thus increased and the nonlinear character of the acoustic response is improved. In addition, the particles stabilize the microbubbles by inhibiting the transfer of gas to surrounding liquid as well as resisting the capillary pressure due to interfacial tension. This thesis commences with a review of the current literature followed by a review of theoretical models for the dynamics and dissolution of free and coated microbubbles. A new dissolution model accounting for the effect of nanoparticles and a surfactant coating is then proposed and simulations compared with experimental results obtained from collaborators. A current dynamic model describing a coated microbubble is evaluated. This is then expanded to provide a new dynamic model for a contrast agent with a finite thickness shell with variable surface tension and viscosity. Finally the microfluidic method for producing contrast agents is studied through a computational fluid dynamic model followed by recommendations for future directions of study

Groundwater resources assessment using integrated geophysical techniques in the southwestern region of Peninsular Malaysia.

Combined geophysical techniques such as multi-electrode resistivity, induced polarization, and borehole geophysical techniques were carried out on volcano-sedimentary rocks in the north of Gemas as part of the groundwater resource’s investigations. The result identifies four resistivity units: the tuffaceous mudstone, tuffaceous sandstone, the tuff bed, and the shale layer. Two types of aquifer systems in terms of storage were identified within the area: one within a fracture system (tuff), which is the leaky area through which vertical flow of groundwater occurs, and an intergranular property of the sandy material of the aquifer which includes sandstone and tuffaceous sandstone. The result also reveals that the aquifer occupies a surface area of about 3,250,555 m2 with a mean depth of 43.71 m and a net volume of 9.798 × 107 m3. From the approximate volume of the porous zone (28 %) and the total aquifer volume, a usable capacity of (274.339 ± 30.177) × 107 m3 of water in the study area can be deduced. This study provides useful information that can be used to develop a much broader understanding of the nature of groundwater potential in the area and their relationship with the local geology

Development and testing of open-jet wind tunnel for quadrotor flight testing

Station keeping of a hovering quadrotor under various turbulent wind condition has gained much attention these days due to its potential application in complex environments. Various types of control algorithm have been developed to increase the performance of the quadrotor under such wind conditions. These need to be tested and verified by flying the quadrotor itself. One of the quick and low-cost solutions would be to set up a test rig by modifying an existing wind tunnel to recreate such wind conditions. In order to cater such experiments, in Universiti Putra Malaysia (UPM), an open-jet wind tunnel was attached to an existing open-loop wind tunnel, which initially has a test area of 1 meter by 1-meter size. By attaching the open-jet wind tunnel which has a diverged shape, the test section area is increased up to 2 meters in diameter size, ensuring sufficient space for manoeuvring and hovering the experimental quadrotor. A settling chamber is attached before the test section to characterize the output wind. The maximum wind speed at the opening is 8 m/s. The extended wind tunnel's flow characteristics are analyzed by anemometer for velocity distribution in four different distance from the opening. It has been found that the wind velocity distribution and turbulent intensity simulate the outdoor wind turbulent condition to test a quadrotor hovering control algorithm

Application of Genetic Algorithm to the Design Optimization of Complex Energy Saving Glass Coating Structure

Attenuation of GSM, GPS and personal communication signal leads to poor communication inside the building using regular shapes of energy saving glass coating. Thus, the transmission is very low. A brand new type of band pass frequency selective surface (FSS) for energy saving glass application is presented in this paper for one unit cell. Numerical Periodic Method of Moment approach according to a previous study has been applied to determine the new optimum design of one unit cell energy saving glass coating structure. Optimization technique based on the Genetic Algorithm (GA) is used to obtain an improved in return loss and transmission signal. The unit cell of FSS is designed and simulated using the CST Microwave Studio software at based on industrial, scientific and medical bands (ISM). A unique and irregular shape of an energy saving glass coating structure is obtained with lower return loss and improved transmission coefficient

Aerodynamic performance of biomimicry snake-shaped airfoil

The cross-section shape and proportionality between geometrical dimensions are the most important design parameters of any lifting surfaces. These parameters affect the amount of the aerodynamic forces that will be generated. In this study, the focus is placed on the snake-cross-section airfoil known as the S-airfoil. It is found that there is a lack of available researches on S-airfoil despite its important characteristics. A parametric study on empty model of the S-airfoil with a cross-section shape that is inspired by the Chrysopelea paradise snake is conducted through numerical simulation. Simulation using 2D-ANSYS FLUENT17 software is used to generate the lift and drag forces to determine the performance of airfoil aerodynamic. Based on the results, the S-airfoil can be improved in performance of aerodynamic by reducing the thickness at certain range, whereby changing the thickness-to-chord ratio from 0.037 to 0.011 results in the increment of lift-to-drag ratio from 2.629 to 3.257. On other hand, increasing the height-to-chord ratio of the S-airfoil will increase maximum lift coefficient but drawback is a wide range of angles of attack regarding maximum lift-to-drag ratio. Encouraging results obtained in this study draws attention to the importance of expanding the research on S-airfoil and its usage, especially in wind energy