National University of Malaysia

About: National University of Malaysia is a education organization based out in Kuala Lumpur, Malaysia. It is known for research contribution in the topics: Population & Heat transfer. The organization has 26593 authors who have published 41270 publications receiving 552683 citations. The organization is also known as: NUM & Universiti Kebangsaan Malaysia.

Boundary Layer Flow over a Continuously Moving Thin Needle in a Parallel Free Stream

Abstract: We investigate the boundary-layer flow on a moving isothermal thin needle parallel to a moving stream. The governing equations are solved numerically by a finite-difference method. Dual solutions are found to exist when the needle and the free stream move in the opposite directions.

Review of brackish water reverse osmosis (BWRO) system designs

Abstract: Brackish water are any water sources with TDS between 1000 and 15 000 mg/L. Brackish water cannot be consumed by us directly due to its high salinity. According to World Health Organization (WHO), water with salinity below 500 mg/L is acceptable as drinking water. There are quite a large number of research that had been done on BWRO. Each of them has agreed with a common design on optimum BWRO design with a slight modification in order to improve more and make a better BWRO system. BWRO systems which have been tested in real situation agree that the single stage system with module connected to reject water is the most optimum system both economically and environmentally. There is some improvement done to the design by using SWRO membrane at the second stage. This improvement increases recovery rate to about 83% and reduces boron concentration at the same time. Another design is by using hybrid combination of ultra-low and conventional RO membranes. Hybrid improves permeate quality. It is also possible to create a hybrid array by mixing membrane element types within a pressure vessel itself. Co-operating an efficient module arrangement into a complete BWRO system will reduce energy consumption. Energy-recovery device is a component that must be included in any small or large-scale systems. A small-scale RO system, without energy recovery, would typically consume two to three times more energy. This will be more for large-scale systems. While single stage system with module connected to reject water is preferred by researchers who have done real environment testing, simulation prefers to add another membrane to the reject water of the second module. This system is yet to be tested in real environment to prove its standing.

Titanium dioxide nanotubes (TNT) in energy and environmental applications: An overview

Abstract: Titanium dioxide nanotubes (TNTs) have attracted a considerable amount of attention over the past several decades. TNTs in the form of high-quality nanotube bundled structures may enhance the performance of several applications and may be suitable in various field; fuel cells, photocatalytic systems, energy storage devices, sensors and environmental analysis systems. The unique properties of TNTs make it able to be use in those field with minimum problems encountered. The fabrication of TNTs was discussed briefly with its advantages and disadvantages stated. Thus, this study investigates the use of TNTs in several promising applications and describes the current problems together with future potential developments in related fields.