Omar S. Dahham

In Vitro Mechanical Properties of Metallocene Linear Low Density Polyethylene (mLLDPE) Nanocomposites Incorporating Montmorillonite (MMT)

The viability of metallocene linear low density polyethylene (mLLDPE) nanocomposites is being investigated as a new material for biomedical application. The effect of filler loadings on the ambient and in vitro (after being exposed in oxidizing condition, 37°C) mechanical properties was studied. We observed that, the mLLDPE nanocomposites have higher mechanical property values as compared to the neat mLLDPE. Furthermore, these properties were less affected by the in vitro conditions. The best ambient and in vitro mechanical properties were achived when 3wt% of organically modified MMT (organo-MMT) was added into the mLLDPE. It was postulated that the presence of MMT layered structure introduced a more tortous path for the diffusing of oxidant molecules, thereby decreasing their permeability towards mLLDPE molecular chains. The smaller amount of oxidants entering the molecular chains resulted in greater retention of mechanical properties when tested in vitro. This preliminary biostability studies show promising properties of the mLLDPE nanocomposite which possess the potential to be further developed for biomedical devices.

Characterization and properties of low-linear-density polyethylene/Typha latifolia composites

ABSTRACT The characterization of the effects of different sizes and loadings of Typha latifolia on the tensile, thermal, and morphological properties of linear-low-density polyethylene (LLDPE)/T. latifolia composites were evaluated using tensile test, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy analyses. Results indicated the tensile strength and elongation at break decreased as T. latifolia loading increased. However, T. latifolia fine size (fs) exhibited better tensile properties than coarse size at the same loading in the composite. T. latifolia (15%, fs) recorded higher thermal stability than LLDPE control and other T. latifolia loadings and sizes due to the strong interaction of T. latifolia (15%, fs) in LLDPE matrix as shown in morphology.

Cure Characteristics, Tensile and Physical Properties of Recycled Natural Rubber Latex Glove (NRL-G) Filled Acrylonitrile Butadiene Rubber

The use of recycled natural latex rubber glove (NRL-G) as a reinforced material filled acrylonitrile butadiene rubber (NBR) was studied. The compounds of different NRL-G loading (0, 10, 20 and 30 phr) were prepared by using two roll mills at room temperature. Two different size ranges of NRL-G such as 300μm-700μm (fine) and 2cm-4cm (coarser) were used. The properties such as cure characteristics, tensile and physical properties were determined. The NBR/NRL-G compound with the fine size of NRL-G exhibits overall good cure characteristics and physical properties compared with coarser size. The addition of the of 20 phr content NRL-G (fine) contributed to the optimum tensile properties than coarser size.

Studies on Tensile Properties of Compatibilized and Uncompatibilized Low-Density Polyethylene/Jackfruit Seed Flour (LDPE/JFSF) Blends at Different JFSF Content

Currently, natural fillers seem to be the suitable materials in polymer industry, which have emerged as a viable and abundant replacement for the relatively high-cost and non-renewable conventional fillers. However, the direct introduction of natural fillers into polymer matrix could effect negatively on some properties. Therefore, the aim of this work is to evaluate the influence of jackfruit seed flour (JFSF) (before and after compatibilization) on the tensile properties of (LDPE/JFSF) blends. Different JFSF content (5, 10, 15 and 20 wt.%) with (63-100 ) particle size were prepared in this work. Twin-screw extruder at 150°C and 50rpm screw speed followed by hot-compress machine at 150°C and 10MPa pressure were used respectively to produce (LDPE/JFSF) blends. Adipic acid (AA) solution was added as a compatibilizer into all blends equally (25wt% AA into 75wt% JFSf). The changes of tensile and morphological properties were investigated. Results shown decreasing on tensile strength and elongation at break of LDPE/JFSF and LDPE/JFSF/AA as JFSF increased. In contrast, Young’s modulus increased up to 10 wt.% of JFSF and then decreased. However, the addition of Adipic acid, particularly for JFSF 5wt.% has improved the tensile properties of LDPE/JFSF blends. The SEM micrographs showed the agglomeration at high JFSF content (20 wt%) which in turn effected negatively on the tensile properties. However, the blends show homogeneous surfaces as AA added.

Curing characteristics tensile and physical properties of rice straw filled standard Malaysian rubber

In this research, the effects of Rice Straw (RS) reinforced Standard Malaysian Rubber (SMRL) on curing characteristics, tensile properties and physical properties were investigated. All compounds were prepared using two roll mill at five different RS loading (10, 20, 30, 40, 50 phr). In addition, two different size of RS, fine size (FS) at 300 μm and coarse size (CS) at 10 mm were used. The properties such as cure characteristics, tensile properties and physical properties were determined. Results indicated that the fine size of RS filled SMRL contributed to the better properties such as tensile, hardness and crosslink density compare to coarser size of RS filled SMRL at same loading.

Synthesis of zinc oxide thin films prepared by sol-gel for specific bioactivity

Zinc oxide (ZnO) thin films this device to used for many application like chemical sensor, biosensor, solar energy, etc but my project to use for bioactivity(biosensor). Zinc oxide (ZnO) thin films have been grown using sol-gel technique. Characterization was done using Scanning Electron Microscope (SEM), Energy Dispersive X-ray(EDX) and Electrical Measurement(I-V). ZnO thin film was successfully synthesized using low cost sol-gel spin coating method. The coupling of DNA probe to ZnO thin film supports modified with carboxylic acid (COOH) is certainly the best practical method to make DNA immobilization and it does not require any coupling agent which could be a source of variability during the spotting with an automatic device. So, selected this coupling procedure for further experiments. The sensor was tested with initial trial with low concentrated DNA and able to detect detection of the disease effectively. Silicon-on-insulator (SOI) wafer device with ZnO can detect at different concentration in order to valid the device capabilities for detecting development. The lowest concentration 1 µM HPV DNA probe can detect is 0.1 nM HPV target DNA.Zinc oxide (ZnO) thin films this device to used for many application like chemical sensor, biosensor, solar energy, etc but my project to use for bioactivity(biosensor). Zinc oxide (ZnO) thin films have been grown using sol-gel technique. Characterization was done using Scanning Electron Microscope (SEM), Energy Dispersive X-ray(EDX) and Electrical Measurement(I-V). ZnO thin film was successfully synthesized using low cost sol-gel spin coating method. The coupling of DNA probe to ZnO thin film supports modified with carboxylic acid (COOH) is certainly the best practical method to make DNA immobilization and it does not require any coupling agent which could be a source of variability during the spotting with an automatic device. So, selected this coupling procedure for further experiments. The sensor was tested with initial trial with low concentrated DNA and able to detect detection of the disease effectively. Silicon-on-insulator (SOI) wafer device with ZnO can detect at different concentration in order...

Lab-on-chip components for molecular detection

We successfully fabricated Lab on chip components and integrated for possible use in biomedical application. The sensor was fabricated by using conventional photolithography method integrated with PDMS micro channels for smooth delivery of sample to the sensing domain. The sensor was silanized and aminated with 3-Aminopropyl triethoxysilane (APTES) to functionalize the surface with biomolecules and create molecular binding chemistry. The resulting Si-O-Si- components were functionalized with oligonucleotides probe of HPV, which interacted with the single stranded HPV DNA target to create a field across on the device. The fabrication, immobilization and hybridization processes were characterized with current voltage (I-V) characterization (KEITHLEY, 6487). The sensor show selectivity for the HPV DNA target in a linear range from concentration 0.1 nM to 1 µM. This strategy presented a simple, rapid and sensitive platform for HPV detection and would become a powerful tool for pathogenic microorganisms screening in clinical diagnosis.We successfully fabricated Lab on chip components and integrated for possible use in biomedical application. The sensor was fabricated by using conventional photolithography method integrated with PDMS micro channels for smooth delivery of sample to the sensing domain. The sensor was silanized and aminated with 3-Aminopropyl triethoxysilane (APTES) to functionalize the surface with biomolecules and create molecular binding chemistry. The resulting Si-O-Si- components were functionalized with oligonucleotides probe of HPV, which interacted with the single stranded HPV DNA target to create a field across on the device. The fabrication, immobilization and hybridization processes were characterized with current voltage (I-V) characterization (KEITHLEY, 6487). The sensor show selectivity for the HPV DNA target in a linear range from concentration 0.1 nM to 1 µM. This strategy presented a simple, rapid and sensitive platform for HPV detection and would become a powerful tool for pathogenic microorganisms screen...

Lattices parameter dependent on effective atomic interactive coefficient in nanostructure

The usage of thick silicon substrates is widespread in electronic industries todays, silicon is the most important material in the semiconductor industries due to its excellent electrical, mechanical and chemical properties. Due to it being inert at room temperature and having anisotropic properties (electrical, mechanical chemical), silicon plays an important role in micro-electro-mechanical systems (MEMS) application. However, atomic interaction becoming complicated as the number of electrons increases. Atomic interaction beyond the hydrogen atom is indeed complex but quite possible by Schrodinger equation. Therefore, combination of models to explain atomic interaction via density functional theory, Kohn Sham and generalized gradient approximation is proposed. It its expected that the SiNW will show band gap transition with the decreasing size and the band gap properties under inter atomic stress. With this, it is possible to determine the atomic structure of nanowire fundamental behavior. Thus, Based o...

Drug carrier in cancer therapy: A simulation study based on magnetic carrier substances

The principle of magnetic carrier is a medium for transferring information by sending the drug to the specific part to kill tumor cells. Generally, there are seven stages of cancer. Most of the patient with cancer can only be detected when reaches stage four. At that stage, the cancer is difficult to destroy or to cure. Comparing to the nearly stage, there are probability to destroy tumor cell completely by sending the drug through magnetic carrier directly to nerve. Another way to destroyed tumor completely is by using Deoxyribonucleic acid (DNA). This project is about the simulation study based on magnetic carrier substances. The COMSOL multiphysic software is used in this project. The simulation model represents a permanent magnet, blood vessel, surrounding tissues and air in 2D. Based on result obtained, the graph shown during sending the magnetic flux is high. However, as its carry information the magnetic flux reducess from the above, the move from 0m until 0.009 m it become the lowers and start increase the flux from this until maximum at 0.018m. This is due the fact that carrier start to increase after because the low information is gradually reduce until 0.018m.The principle of magnetic carrier is a medium for transferring information by sending the drug to the specific part to kill tumor cells. Generally, there are seven stages of cancer. Most of the patient with cancer can only be detected when reaches stage four. At that stage, the cancer is difficult to destroy or to cure. Comparing to the nearly stage, there are probability to destroy tumor cell completely by sending the drug through magnetic carrier directly to nerve. Another way to destroyed tumor completely is by using Deoxyribonucleic acid (DNA). This project is about the simulation study based on magnetic carrier substances. The COMSOL multiphysic software is used in this project. The simulation model represents a permanent magnet, blood vessel, surrounding tissues and air in 2D. Based on result obtained, the graph shown during sending the magnetic flux is high. However, as its carry information the magnetic flux reducess from the above, the move from 0m until 0.009 m it become the lowers and start inc...

Calculation of the band structure parameter in silicon nanowires using first principle analytical method

Silicon is the most important material in semiconductor industry. As nano-devices shrink in size, the conventional understanding of electronic devices are no longer applicable as quantum effects start to play an important role for the behavior of the device. At the same time, when structures are approaching atomic scale, the precise fabrication by photo-lithographic techniques, for example, are not even applicable. Very often, the fabrication of regular structures rely on self-assembly is susceptible to fluctuations. Therefore, a deeper understanding to exploit the quantum behavior of nano-devices and precise control of building nano-structures are highly desired. Thus, genetic algorithm based on first principle analysis to optimize silicon nanowires electron and elastic properties is proposed. One nanometer (1nm) surface reconstruction by using genetic algorithm combined with ab-initio calculation is proposed. The SiNWs behavior to quasi-direct band gap transition with the decrease size and the band gap ...