The phenolic Schiff bases I-VI were synthesized by condensation reactions between various diamines, namely o-dianisidine, o-tolidine and ethylenediamine with vanillin or p-hydroxybenzaldehyde and subsequent reactions between these phenolic Schiff bases and epichlorohydrin to produce new diglycidyl ethers Ia-VIa. The structures of these compounds were confirmed by CHN, FT-IR, (1)H-NMR, and (13)C-NMR spectroscopy. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). All the diglycidyl ethers prepared exhibit nematic mesophases, except for Va and VIa, which did not show any transition mesophases, but simply flow to liquids.
Nitrogen loss from urea fertiliser due to its high solubility characteristics has led to the invention of controlled release urea (CRU). Majority of existing CRU coatings are produced from a non-biodegradable, toxic and expensive synthetic polymers. This study determines the feasibility of fly ash-based geopolymer as a coating material for urea fertilizer. The effects of fly ash particle size (15.2 μm, 12.0 μm, and 8.6 μm) and solid to liquid (S : L) ratio (3 : 1, 2.8 : 1, 2.6 : 1, 2.4 : 1 and 2.2 : 1) on the geopolymer coating, the characterization such as FTIR analysis, XRD analysis, surface area and pore size analysis, setting time analysis, coating thickness, and crushing strength, and the release kinetics of geopolymer coated urea in water and soil were determined. Lower S : L ratio was beneficial in terms of workability, but it had an adverse impact on geopolymer properties where it increased porosity and decreased mechanical strength to an undesirable level for the CRU application. Geopolymer coated urea prepared from the finest fly ash fraction and lowest S : L ratio demonstrated high mechanical strength and slower urea release profile. Complete urea release was obtained in 132 minutes in water and 15 days in soil from geopolymer-coated urea whereas for uncoated urea it took only 20 minutes in water and 3 days in soil. Thus, geopolymer can potentially be used as a coating material for urea fertilizer to replace commonly used expensive and biodegradable polymer-based coatings.
Thalassaemia is one of the most common autosomal recessive blood disorders in the world and its carrier status is prevalent in nearly 15% of Malaysian population. The global and economic burden for lifelong care of those affected increases every year. Currently, there is no policy on thalassaemia-carrier screening for couples prior to marriage besides HIV/AIDS screening in Malaysia. Other countries such as Iran, Iraq, Turkey, Bahrain and Saudi Arabia have established a policy for thalassaemia prevention by conducting premarital thalassaemia screening. Zero thalassaemia cases in new-born child in Cyprus have proven that thalassaemia can be prevented. This study aimed to investigate the willingness of premarital Malays on premarital thalassaemia screening.
A set of questionnaire was distributed to 57 persons at premarital course sites and wedding fairs and expositions held in Kuala Lumpur and Selangor. Components in the questionnaire included: 1) demographic 2) knowledge about thalassaemia, signs and screening method 3) attitudes towards thalassaemia premarital screening 4) practices of premarital thalassaemia screening. Analysis for the questionnaire was performed using IBM SPSS Statistics 23.0.