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Bare cadmium sulfide (CdS) nanocrystals were successfully synthesized by the thermolysis of a single-source organometallic precursor, cadmium chloride hemipentahydrate (CdCl 2 · 2.5H 2 O) with thiourea in ethanol. The microstructure of the CdS samples was characterized using XRD, TEM, and Raman spectroscopy. The XRD's results showed that there was a transformation from cubic to hexagonal crystalline phase when higher mass of CdCl 2 · 2.5H 2 O was used. Further experimental with different Cd 2+ source showed ion Cl − originated from CdCl 2 · 2.5H 2 O attributed to this crystalline phase transformation. The UV-Visible analysis indicated that quantum confinement effect took place when compared to the bulk CdS. However, the photoluminescence experiments revealed that the red-light emission was observed in all samples. This finding could be ascribed to deep trap defects that were due to sulfur vacancies as suggested by XPS and also the fact that the bare CdS nanoparticles are in contact with each other as shown in the TEM images.

New poly(azomethine urethane)s were synthesized in the conventional literature manner by reacting a new bisphenol-containing azomethine group, N,NЈ-bis(4-hydroxyl-3-methoxy benzylidine)-2,6-diaminopyridine (I) with various diisocyanates, such as hexamethylene diisocyanate (HDI) (a), methylene-4,4Ј-diphenyl diisocyanate (MDI) (b), and toluene-2,4-diisocyanate (TDI) (c). The resulting polymers I(a-c) were confirmed by 1 H-NMR, FTIR, UV, and CHN analyses. Thermogravimetric analysis (TGA) revealed that the polymers have high thermal stability. A semicrystalline behavior was noticed for polymers by wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC).

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In this study, 25-year-old oil palm biomass (OPB) fiber-polypropylene (PP) composites are prepared by five different fiber loadings (10, 20, 30, 40, and 50%). The types of OPB used are oil palm empty fruit bunches, oil palm frond, and oil palm trunk. Transmission electron microscopy has confirmed that the cell wall structures of the various oil palm fibers have different cell wall thicknesses and exhibit the same ultrastructure as that of wood. The fibers consist of middle lamella, primary, and thick secondary walls with different thicknesses for different types of fibers. The secondary wall is differentiated into a S 1 layer, a unique multi-lamellae S 2 layer, and a S 3 layer. OPB fibers are compounded with PP using a Brabender DSK 42/7 twin screw extruder. The mechanical features such as tensile, flexural and impact properties of the OPB-PP composite are studied. The melt flow index (MFI) of the composite materials is also studied. Generally, the results show that lower fiber loading (10%) exhibits the highest tensile strength and MFI properties as compared to higher fiber loading (50%). Evidence of a fiber-matrix interphase is analyzed using scanning electron microscopy.