Microemulsion Polydispersion Due to Polymer Solubilization

Freeze-fracture electron microscopy results on water-in-oil microemulsion showed that significant polydispersion can be induced by adding water soluble polymers

The development of simulation model of carrier injection in quantum dot laser system

The development simulation model of quantum dot (QD) laser is performed based upon rate equations for the carriers and photons in energy states. The rate equation is solved by using Matlab, Runge-Kutta method. In this paper shown that by increasing carrier injection to the active medium of laser, switching-on and stability time of the system would decrease while output power at peak and stationary will be increased. Indirect (non-instantaneous) carrier injection into QD is an essential component of our model and it describes the actual situation for QD laser

Hydrogen Peroxide (H2O2) Biosensor Based on the Conducting Polymer Using Self-Assembly Technique

Biosensors are in principle fabricated by immobilized biomaterials on a detector membrane and combining them with electrochemical equipment. The applications of enzyme-based biosensors can be explored such as in the process of gas detection, medicine, pathogen detection and detection of toxic levels of substances before and after bioremediation. In this study, H2O2 detection was performed using HRP/PANI, HRP/PPY, HRP/PT and HRP/PT/PPY/PANI layers. The HRP/PANI layer from Variable Pressure Scanning Electron Microscopy (VPSEM) image exhibited a dry surface. The HRP/PPY layer exhibited a surface with agglomerate molecules. The HRP/PT layer, on the hand, exhibited a layer surface with almost the same molecular size. This is confirmed by the higher surface roughness value for HRP/PPY compared to other layers obtained via characterization with Atomic Force Microscopy (AFM). The increasing current response for all three layers was arranged in HRP/PANI> HRP/PT> HRP/PPY. VPSEM and AFM images exhibited surfaces with molecules being in an agglomeration state after the H2O2 detection process. In terms of current response, the response rate of H2O2 on the surface of the HRP/PT/PPY/PANI electrode caused the current response obtained to be fast. The roughness value increased with time due to the reaction that took place between the surface of the HRP/PT/PPY/PANI layer with H2O2. The day-based current response showed that day 1 to day 14 exhibited a uniform graph pattern but from day 21 to day 30 there was a change in the graph pattern due to the HRP/PT/PPY/PANI layer undergoing degradation. The activity of the HRP enzyme was studied by looking at its absorption effect for 30 days. From day 1 to day 14, there was a difference in the overall rate of absorption. However, from day 21 to day 30, the rate of absorption remained constant which explains the slowing down of HRP activity &nbsp

Hydrogen Peroxide (H2O2) Biosensor Based on the Conducting Polymer Using Self-Assembly Technique

Biosensors are in principle fabricated by immobilized biomaterials on a detector membrane and combining them with electrochemical equipment. The applications of enzyme-based biosensors can be explored such as in the process of gas detection, medicine, pathogen detection and detection of toxic levels of substances before and after bioremediation. In this study, H2O2 detection was performed using HRP/PANI, HRP/PPY, HRP/PT and HRP/PT/PPY/PANI layers. The HRP/PANI layer from Variable Pressure Scanning Electron Microscopy (VPSEM) image exhibited a dry surface. The HRP/PPY layer exhibited a surface with agglomerate molecules. The HRP/PT layer, on the hand, exhibited a layer surface with almost the same molecular size. This is confirmed by the higher surface roughness value for HRP/PPY compared to other layers obtained via characterization with Atomic Force Microscopy (AFM). The increasing current response for all three layers was arranged in HRP/PANI> HRP/PT> HRP/PPY. VPSEM and AFM images exhibited surfaces with molecules being in an agglomeration state after the H2O2 detection process. In terms of current response, the response rate of H2O2 on the surface of the HRP/PT/PPY/PANI electrode caused the current response obtained to be fast. The roughness value increased with time due to the reaction that took place between the surface of the HRP/PT/PPY/PANI layer with H2O2. The day-based current response showed that day 1 to day 14 exhibited a uniform graph pattern but from day 21 to day 30 there was a change in the graph pattern due to the HRP/PT/PPY/PANI layer undergoing degradation. The activity of the HRP enzyme was studied by looking at its absorption effect for 30 days. From day 1 to day 14, there was a difference in the overall rate of absorption. However, from day 21 to day 30, the rate of absorption remained constant which explains the slowing down of HRP activity &nbsp

Vesicles and lamella: outcome of the changing formation path of a sodium N-lauroylsarcosinate hydrate/1-decanol/water system

Vesicles are closed bilayers that enclose a part of the continuous phase inside the core. In spherical shape, they attain the minimum free energy state. Conversely, lamella with maximum free energy remain in planer bilayer shape in the colloidal dispersion. Even with the same amphiphile concentration the colloidal structures depend on different parameters, many of these already addressed in different reports. However, the effect of mixing procedure as a formation path is unidentified. Here we reported water in 1-decanol and 1-decanol in water; these two different mixing procedures yield vesicles and lamella at the same point of the phase diagram of a sodium N-lauroylsarcosinate hydrate/1-decanol/water system. It was found that the favorable and unfavorable contact of water with the weak tertiary ammonium cation in amino-acid head-group plays the crucial role in this process. Moreover, this weak cationic property of this amphoteric surfactant can be exploited to carry DNA for gene therapy with a nontoxic system instead of cationic

A hydrogen peroxide biosensor based on nanoparticle PANI/HRP electrode

Recently, conducting polymers have attracted much interest in the development of biosensor. It contain π- electron backbone responsible for its unusual electronic properties such as electrical conductivity, low energy optical transitions, low ionization potential and high electron affinity. When the Horseradish peroxidase (HRP) was immobilized to the conducting polymers, these polymers possesses the ability to bind oppositely charged complex entities in their neutral insulating state. Determination of Hydrogen peroxide (H2O2) and other organic peroxides is of practical importance in clinical, environmental and many other fields. This study intends to see the role and properties of PANI/HRP layer towards H2O2 by measuring its current. Langmuir- Blodgett technique was used to form the PANI monolayer and the HRP was deposited in PANI monolayer by using electrodeposition method. Results from U.V.- visible spectrum of PANI with and without HRP shows two sharp absorption peaks at 320 nm and 720 nm. PANI forms as nanoparticles was revealed by VPSEM. AFM shows the image in roughness before and after the HRP was deposited on PANI monolayer. The current and response of H2O2 towards PANI/HRP electrode increases demonstrating effective electrocatalytic reduction of H202. PANI/HRP electrode not only act as excellent materials for rapid electron transfer but also for the fabrication of efficient biosensors

Kesan kepekatan glukopon 215 csup terhadap saiz dan sifat magnet nanozarah Co-Ni-Cu yang disediakan dengan kaedah elektropengendapan

Nanozarah Co-Ni-Cu telah disediakan dengan kaedah elektropengendapan pada keupayaan pengendapan -925 mV (SCE) menggunakan larutan sulfat (0.018M Co2++ 0.180M Ni2+ + 0.002M Cu2+) yang mengandungi surfaktan Glukopon 215 CSUP dan juga tanpa surfaktan. Kesan kepekatan surfaktan terhadap saiz dan sifat magnet nanozarah Co-Ni-Cu yang terhasil telah dikaji. Analisis morfologi permukaan endapan yang diperoleh dilakukan dengan menggunakan mikroskop elektron imbasan pancaran medan (FESEM) manakala sifat magnetnya diselidiki dengan menggunakan magnetometer getaran sampel (VSM). Nanozarah Co-Ni-Cu yang disediakan daripada larutan yang mengandungi Glukopon 215 CSUP didapati berbentuk sfera dengan saiz berskala nanometer. Saiz zarah paling kecil ialah lebih kurang 50 nm, diperoleh pada kepekatan surfaktan 5 %v, iaitu kepekatan paling tinggi yang dikaji dalam kajian ini. Kepaksaan (Hc) didapati lebih tinggi pada sampel yang disediakan daripada elektrolit yang mengandungi surfaktan berbanding tanpa surfaktan