This research aimed to enhance the antibacterial activity of silver nanoparticles (AgNPs) synthesized from silver nitrate (AgNO₃) using aloe vera extract. It was performed by means of incorporating AgNPs on an activated carbon nanoparticle (ACNPs) under ultrasonic agitation (40 kHz, 2 × 50 watt) for 30 min in an aqueous colloidal medium. The successful AgNPs synthesis was clarified with both Ultraviolet-Visible (UV-Vis) and Fourier Transform Infrared (FTIR) spectrophotometers. The successful AgNPs–ACNPs incorporation and its particle size analysis was performed using Transmission Electron Microscope (TEM). The brown color suspension generation and UV-Vis’s spectra maximum wavelength at around 480 nm confirmed the existence of AgNPs. The particle sizes of the produced AgNPs were about 5 to 10 nm in the majority number, which collectively surrounded the aloe vera extract secondary metabolites formed core-shell like nanostructure of 8.20 ± 2.05 nm in average size, while ACNPs themselves were about 20.10 ± 1.52 nm in average size formed particles cluster, and 48.00 ± 8.37 nm in average size as stacking of other particles. The antibacterial activity of the synthesized AgNPs and AgNPs-immobilized ACNPs was 57.58% and 63.64%, respectively (for E. coli); 61.25%, and 93.49%, respectively (for S. aureus). In addition, when the AgNPs-immobilized ACNPs material was coated on the cotton and polyester fabrics, the antibacterial activity of the materials changed, becoming 19.23% (cotton; E. coli), 31.73% (polyester; E. coli), 13.36% (cotton; S. aureus), 21.15% (polyester; S. aureus).

This paper presents a characterization of an integrated ozone generator constructed by seven of reactors of Dielectric Barrier Discharge Plasma (DBDP). DBDP a has spiral-cylindrical configuration. Silence plasma produced ozone inside the DBDP reactor was generated by AC-HV with voltage up to 25 kV and maximum frequency of 23 kHz. As a source of ozone, dry air was pumped into the generator and controlled by valves system and a flowmeter. We found ozone concentration increased with the applied voltage, but in contrary, the concentration decreased with the flow rate of dry air. It was also found that a maximum concentration was 20 mg/L and ozone capacity of 48 g/h with an input power of 1.4 kW. Moreover, in this generator, IP efficiency of 8.13 g/kWh was obtained at input power 0.45 kW and air flow rate of 9 L/min. Therefore, be the higher ozone capacity can be produced with higher input power; however, it provided lower IP efficiency. The effect of dry air flow rate and applied voltage on ozone concentrations have been studied. At last, spiral wire copper was very corrosive done to the interaction with ozone, and it is necessary to do a research for finding the best metals as an active electrode inside of the quartz dielectric.

Porous Polystyrene nanospheres (PSNs)-Cd metal thin film of about 375.72 angstrom (Ǻ) on hydrophilic silicon wafer has been successfully fabricated from its liquid colloidal prepared by 40 KHz ultrasound for 45 minute at room temperature. This porous fabrication was aiming to confirm the proposed structure of PSNs based-porous thin film models depicted in Fig.1. Surface morphology of the porous thin film explored with a field emission scanning electron microscopy (FESEM) showed that Cd metals atomic particles might be deposited on the PSNs particles surface so that they could enhance the porosity of the thin film material. Absorption capability of the porous thin film assayed using both ultraviolet-visible (UV-Vis) and infrared (IR) light proved that Cd metals atomic particles were a main part of the porous thin film which could enhance significantly the absorption performance. It could be concluded that both kind of nano- sunken and nano-wells unique binding sites might have been generated inside the pores during fabricating them

The research was aiming to investigate the potency of water hyacinth (WH) biochar as the most advantageous sound absorber composite when it was blended with polyvinyl alcohol (PVA). It was the first time using WH biochar-based composite as a sound absorber material. Analysis and characterization of the produced WH biochar were essentially performed using N₂ absorption–desorption, FTIR spectrophotometer, and SEM methods. While the capability of the sound absorber material was technically conducted using a polyvinyl chloride (PVC) impedance tube of about 95 cm in length with internal and outer diameters of about 9.5 cm and 9.8 cm respectively. The materials that would be tested for their capability of sound absorber were prepared in a disk-like form with about 9.5 cm in diameter and 0.5 cm in thickness. The sound source was continuously turned on for 2 min and transmitted wirelessly through the impedance tube, and the decreasing intensity of the sound was recorded every 5 s. The results showed that the sound absorption coefficient (SAC) of the WH biochar-PVA composite was about 6.50% (0.0650) up to 21.03% (0.2103), while the SAC of the Styrofoam was just about 4.37% (0.0437). This research concluded that the WH biochar produced by the thermal energy of 500 °C indicated it could be the best sound absorber composite when it was blended with PVA, especially for a low frequency of about 440 Hz.

The effects of solar radiations on physical properties and molecular structures of 200 nm polystyrene nanospheres (PSN) coated on silicon wafer were explored by field emission scanning electron microscope (FESEM) and attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectrometer. It is revealed the particles shape of PSN changed from spherical to dumbbell‐like shape after solar irradiation. Reduction of the PSN size as much as 23.79% after 5 minutes exposure was also observed in PSN particles. We believed that some of the phenyl moieties of polystyrene broke down to facilitate carbon‐carbon cross linkage bonds intra‐ as well as inter‐PSN particles and were shown by ATR‐FTIR spectrums. These results proven the shrinkage of PSN particles were caused by the change of the molecular structure of the irradiated PSN to be much more dense material.

Some of the secondary metabolites present in red algae are terpenoids, quinones, flavonoids, alkaloids, essential oils, diarylheptanoids, steroids, cardioglycosides, oils and fats, tannins, carbohydrates. Activity of rhizomes, leaves and flowers red leaf is as antimicrobial, anti-fungal, anti-oxidants, anti-tumor, anti-cancer and vasodilator. One way to improve the physical, chemical and bioactivity properties of natural compounds was to make them into nanoparticles. In this study, the isolation of bioactive compounds contained in red laos rhizome by maceration method using ethanol solvent was done, then partitioned with n-hexane and ethyl acetate. The extracts thus obtained are fabricated into nanoparticles. Extracts in bulk and nanoparticles were then tested for cytotoxic activity using BSLT method. Results of analysis with PSA showed that ethanol extract had size 410,8 nm, n-hexane extract 220,7 nm and ethyl acetate extract 208,3 nm. The results of cytotoxic tests showed that nanoparticle size increased cytotoxic activity. Ethyl acetate extract was most active compared to ethanol and n-hexane extracts with LC50values of 17.919; 84,956; 166,526 ppm. Whereas the nanoparticle size was respectively 10,491; 74,072 and 84,197 ppm. Cytotoxic activity increases with nanoparticle fabrication.