Der-Chi Tien

The study of hydrophilic characteristics of ethylene glycol

This paper describes the way to measure Ethylene Glycol resistance (Ω). The Electronic Sensing of Hydrophilic Characteristics was design to measure Ethylene Glycol moisture contain in real-time. Many liquids contain the Glycol such as brake fluid, antifreeze and cosmetic. The percent of water contain may affect those liquids functions. It will measure the Ethylene Glycol resistance (Ω) and could be converted into voltage for the use of moisture meter. The relation between Ethylene Glycol with moisture contain and its resistance (Ω) is closed to linear. The hydrophilic characteristics is the molecular model of OH structure which has a Hydrogen atom (H) bonded to the Oxygen atom (O) ; it will absorb the electron cloud at the outer layer of Hydrogen atom; so the electrons within O-H bond have a higher probability of appearance around the Oxygen atom. The O-H bond is similar to a chemical bond which can absorb the water molecules.

Study of Ag and au nanoparticles synthesized by arc discharge in deionized water

The paper presents a study of Ag and Au nanofluids synthesized by the arc discharge method (ADM) in deionized water. The metallic Ag nanoparticle (Ag0) and ionic Ag (Ag+) have played an important role in the battle against germs which are becoming more drug-resistant every year. Our study indicates that Ag nanoparticle suspension (SNPS) fabricated by using ADM without added surfactants exclusively contains the metallic Ag nanoparticle and ionic Ag. Besides that, the ADM in deionized water has also been employed for the fabrication process of Au nanoparticles. The experimental results indicate that the prepared Ag nanoparticles can react with the dissolved H2CO3 in deionized water, leading to the formation of Ag2CO3. Significantly different to Ag, the prepared Au nanoparticles with their surfaces bonded by oxygen are suspended in deionized water by the formation of hydrogen bonded with the neighboring water molecules.

Motion artifacts in CT scans: a study by computer simulation and mechanical phantom

Computed tomography (CT) is one of the most important tools in the diagnosis of thoracic tumors. However, during the scanning process, respiratory motion causes changes in the position and shape of the tumor, creating motion artifacts in the CT scan. This can lead to misdiagnosis of the size and position of the tumor, and can affect the effectiveness of treatment. This study develops a computer model of the movement of the thorax, and simulates the movement of a lung tumor caused by breathing during a CT scan. We show that adjusting the CT slice thickness is sufficient to determine the center of displacement and maximum displacement of a tumor during normal breathing. This model can be applied in the clinical diagnostic use of CT equipment. It will assist in finding the position of lung tumors from motion artifacts in CT scans. The target margin for treatment can thus be defined more accurately, so that appropriate doses of radiation can be applied to the target area, and irradiation of healthy tissue avoided.

Spark Parameter Monitoring Feedback System for Preparation of Nanosilver Colloid in EDM

This study developed a system monitoring the electric discharge machines (EDM) discharge energy and success rate to replace conventional oscilloscope observation. By using logic circuit, the signals are transmitted to the PC monitoring platform in order to display the discharge success times, discharge success rate, and electrodes consumption energy. The advantage of the proposed system is the capability to observe real-time discharges and record the experimental conditions, as well as optimize the discharge parameter settings. The experimental results suggest that, in the preparation of nanosilver colloid, the cost-performance of Ton–Toff at 10–100 µs is the optimal setting. The monitoring system also can take advantage of the discharge success rate to control the energy consumption of the electrode to obtain the standardization of products. The results suggest that, while discharge success rate, electrodes weight loss and wavelength of the absorption peak are considerably accurate, but concentration accuracy is relatively poor. The discharge success rate monitoring system is an innovative method that can help to realize electric discharge processing, optimize product quality, and it may be a powerful processing tool in the future.

A Study of Antibioactivity of Nanosilver Colloid and Silver Ion Solution

The colloidal silver solution was successfully prepared in dielectric fluid by using electrical spark discharge (ESD) without any surfactants. It does not require the toxic chemical agents in the process, which may affect the effectiveness of nanosilver colloid as an antibacterial agent. Nanocolloidal silver produced by ESD is characterized as low cost, zero environmental pollution, continuous, and rapid mass production process. In order to test the effect of antibioactivity, nanosilver dough was tested; the silver nanofluid was prepared by ESD machine, made into dough at different concentrations, and fermented for three hours in order to observe changes in the diameter of the dough. The results showed that the effect of effectiveness of nanosilver at the concentration of 100 ppm was weak, whereas the effect of 60 ppm silver ion (100 ppm AgNO3) was significant, as the dissociation rate of silver ion concentration correlates to the antibioactivity.

Temperature Effect on the Stability of CuO Nanofluids Based on Measured Particle Distribution

This study aims to investigate the temperature effect on particle size of copper oxide nanofluid produced under optimal parameters of the Arc Spray Nanoparticle Synthesis System (ASNSS) developed in this research. The purpose is to understand the aggregation feature of copper oxide nanofluid in a higher-than-room-temperature environment and to analyze its size change and the motion behavior of suspended nanoparticles. This study employs an ambient temperature controller to maintain the environment temperature within the scope of normal fluid work temperature to obtain data on the change in suspended particles of copper oxide nanofluid under varying temperatures and through change of time. Experimental result shows that the particle size distribution of copper oxide nanofluid changes when the temperature rises due to the slight absorption and aggregation phenomena between particles, and that the change in environmental temperature can accelerate the aggregation of copper oxide nanofluid, which can affect its stability in application. However, the change in particle size distribution will gradually stabilize for a longer duration of constant temperature.

Photodecomposition of gaseous toluene using TiO2 prepared by SANSS

This study examined the photodecomposition of volatile organic compounds (VOCs) using TiO2 catalyst fabricated by the Submerged Arc Nanoparticle Synthesis System (SANSS). The TiO2 catalyst was employed to decompose gaseous toluene and compared with Degussa- P25 TiO2 in terms of decomposition efficiency. It was found that gaseous toluene exposed to UV irradiation produced intermediates that were even harder to decompose. After 60-min of photocomposition, Degussa-P25 TiO2 reduced the concentration of gaseous toluene to 8.18% while the concentration after decomposition by SANSS TiO2 catalyst dropped to 0.35%. The results show that TiO2 prepared by SANSS has great efficiency in decomposing both gaseous toluene and its intermediates.

Interactive Relationship between Silver Ions and Silver Nanoparticles with PVA Prepared by the Submerged Arc Discharge Method

This study uses the submerged arc discharge method (SADM) and the concentrated energy of arc to melt silver metal in deionized water (DW) so as to prepare metal fluid with nanoparticles and submicron particles. The process is free from any chemical agent; it is rapid and simple, and rapid and mass production is available (0.5 L/min). Aside from the silver nanoparticle (Ag0), silver ions (Ag+) exist in the colloidal Ag prepared by the system. In the preparation of colloidal Ag, polyvinyl alcohol (PVA) is used as an additive so that the Ag0/Ag+ concentration, arcing rate, peak, and scanning electron microscopic (SEM) images in the cases with and without PVA can be analyzed. The findings show that the Ag0/Ag+ concentration increases with the addition level of PVA, while the nano-Ag and Ag+ electrode arcing rate rises. The UV-Vis absorption peak increases Ag0 absorbance and shifts as the dispersity increases with PVA addition. Lastly, with PVA addition, the proposed method can prepare smaller and more amounts of Ag0 nanoparticles, distributed uniformly. PVA possesses many distinct features such as cladding, dispersion, and stability.

Comparison of graphene impregnated with/without nanosilver prepared by submerged arc discharge method:

In this study, submerged arc discharge method (SADM) was used to prepare graphene-nanosilver composites (graphene impregnated with nanosilver) and verified whether it can be prepared under different methods. The optical properties, zeta potentials, and particle sizes of the composites were analyzed through ultraviolet–visible spectroscopy and Zetasizer. The suspensibility of composites were much better than that of noncomposites. Then, we compared the components of composites and noncomposites through transmission electron microscopy. The results confirmed that even when fabricated from similar materials, the composites and noncomposites yielded by SADM featured significantly different properties.

Relationship between Ag nanoparticles and Ag ions prepared by arc discharge method

Abstract This study used the submerged arc discharge method (SADM) to produce metal fluid containing nanoparticles and submicron particles, whereby the energy focused by an electric arc was used to disintegrate silver (Ag) metal in deionized water (DW). No additional chemical substances were required throughout the process, which enabled production to be fast and straightforward. This study proposed using colorimetry to define the interrelation between concentration and nano Ag as well as the Ag ions (Ag+) within a nano silver colloid (NSC) of a specific dilution factor, involving ultraviolet-visible (UV-Vis) spectroscopy and the measuring of electrical conductivity. The results showed that Ag+ activity increased under various dilution conditions, displaying an upward trend in activity with an increase in the dilution factor. The absorption values of Ag+ and nanoparticles increased over time, and the Ag+ activity increased by up to a factor of two after its dilution. Therefore, the Ag+ and nanoparticles demonstrated an interdependence between each other.