2012.4
About Instruments Today No. 187
Rapid Chemical Analysis by Using Ambient Mass Spectrometry [ 下載 PDF ]
Chih-Chiang Chou, Min-Zong Huang, Jentaie Shiea
In past few years, ambient ionization sources, which has witnessed a flurry of developments, is a set of useful techniques for the analysis of samples under open-air conditions. The state-of-the-art of the technique allows direct, rapid, real-time, and high-throughput analyses with little or no sample pretreatment. It also provides the analyses of a wide range of substances from various surfaces and matrices. In the study, we describe a novel ionization method for rapid chemical analysis. This so-called thermal desorption electrospray ionization (TD-ESI) combines thermal desorption of sample analytes from solids or liquids and post ionization via electrospray. Basically, TDESI technique involves three independent steps: sampling, desorption, and ionization. As equipped with a mass spectrometer, it is quite suitable for the direct, rapid, real-time and in-situ analysis. Here, we report the principle, operation and also its wide range of applications including food safety, pesticide, residue, forensic science, and drug abuse.
Surface Signal Enhancements of Raman Scattering and Its Applications [ 下載 PDF ]
Ching-Hsiang Chen, Chih-Ching Huang, Kuan-Jung Chen, Bing-Joe Hwang
Raman scattering technology is a powerful tool to identify molecule structures and atomic interactions and it has been widely applied in different fi elds. In this paper, we introduced the theories and instruments of surface enhanced Raman scattering (SERS) and tip enhanced Raman scattering (TERS) technologies. For the case of the SERS, we proposed two examples for the applications of surface enhanced Raman scattering including liquid molecules and solid state thin fi lms. One is the combination of nanotechnology and surface enhanced Raman scattering to evaluate the scattering intensity of dilute dye molecules in liquid solution by controlling the size of nanoparticles. The other is the identifi cation of solid state conductor polymer fi lms. We deposited the conductor polymer fi lm and dispersed nanoparticles by cycle volumetric method. We further controlled the redox potential by potential stat to evaluate in the inner structure transformations. For the case of the TERS, we provided a case as to identify graphene structures to demonstrate the orientation function of the TERS.
Far-Field Optical Properties of One-Dimensional Gold-in-Ga2O3 Complex Nanowires [ 下載 PDF ]
Yi-Jen Wu, Chia-Wei Hsu, Li-Jen Chou
This work aims to explore and study a wide range of peculiar far-fi eld optical properties of one-dimensional goldin- Ga2O3 peapod and gold-in-Ga2O3 core-shell nanowires. Single-crystalline gold-in-Ga2O3 nanowires have been synthesized systematically by vapor-liquid-solid method. Light-scattering properties and light-interference phenomena of individual gold-in-Ga2O3 nanowires were investigated by dark-field optical microscopy (OM). Light-emission properties of gold-in-Ga2O3 nanowires were studied by photoluminescence (PL). The major peaks in measured scattering spectra were suggested to result from plasmonic resonance of the gold nanopeas and nanorods embedded in the Ga2O3 nanowires. Light-interference spectra of single gold-in-Ga2O3 peapod nanowires demonstrated their applicability of being plasmonic nano-resonators. Photoluminescence of gold-in-Ga2O3 nanowires indicated that luminescence of Ga2O3 matrix further excites localized plasmon resonance in inner gold nanostructures.
The Influence of Growth Temperature on the Microstructures of InN Epitaxial Films [ 下載 PDF ]
Wei-Lin Wang, Wei-Chun Chen, Shou-Yi Kuo, Fang-I Lai, Chien-Nan Hsiao, Li Chang
InN epitaxial films were grown on GaN templates by plasma assisted chemical beam epitaxy method. The growth temperatures of InN fi lms were set as 450 °C, 500 °C, and 550 °C. The microstructures of InN films were characterized by using transmission electron microscopy (TEM). Based on the results of TEM observations, the formation of InN film with the growth temperature of 450 °C consists of slightly tilted grains. The growth rate of InN film deposited at 500 °C is the fastest among three samples. The surface morphology of InN film is also relatively flatter under 500 °C. However, InN film grown at 500 °C contains the highest defect density. With the growth temperature of 550 °C, voids appear in InN film. In InN films, the predominant planar defects are basal stacking faults (BSFs) with the displacement vectors of 1/6 <2203>. In addition to BSFs, dislocations with Burgers vectors of 1/3 <1120> are the major line defects.
Dedication and Qualifi cation Technology for the Components of Nuclear Instrumentation and Control System [ 下載 PDF ]
Yao-Tung Hsu, Hao Wang, Hsin-Chen Chiang, Hsueh-Chao Ko, Chia-Wei Tu
Since 311 Fukusihma nuclear accidents, this nuclear disaster put the operation safety of the nuclear power plant in the spotlight around the world. The periodic maintenance, inspection and component replacement are key factors to keep the nuclear power plant operating safely. Due to decrease of the manufacturers of the nuclear components, the dedicated commercial-grade item to be used as substitute becomes very important to maintaining the plant safety operation. This report describes the nuclear instrumentation and control system design and its aging management, and then to discuss the nuclear commercial-grade item dedication and qualifi cation system in Taiwan. Furthermore, the cases study to provide the application of the methodology, procedures, and the code and standards used in dedication and qualifi cation process.
High Reliability Digital Instrumentation and Control Technique for Triple Modular Redundancy Fault Tolerant Controller [ 下載 PDF ]
Shian-Shing Shyu, Chang-Kuo Chen
Digital instrumentation and control (DI&C) systems have been applied in industry widely. Taking the advantages of communication and self-diagnostic capabilities of digital equipments, they can be confi gured as a redundant control system to maintain application's design function by voting mechanism when single equipment malfunction occurs owing to environmental effect or component failure. This paper presents designs of several triple modular redundant (TMR) controllers used worldwide and the development of a TMR controller by domestic effort.
A Decentering Inspection System on Optical Lens by Image Processing [ 下載 PDF ]
Yung-Hsiang Chen, Chia-Wei Hsu, Tai-Shan Liao
In recent years, according to the growing demand for mobile phone terminal market and smart phone shipments, the global demand of mobile phone camera modules are increased. Based on the lightweight, compact and high precision of the optical system, the errors of the processing and assembly for the optical components have great infl uences on the optical system, especially for the imaging lens of mobile phone camera module. For such axial symmetry of optical components in the production or systems assembly, if the principal axis has coincidence error with the rotation axis of symmetry, the decentration error will be occurred. In the past, the traditional inspection by using the transmission or refl ection measurements is limited to the geometry and size of the lens, so that the inspection is incapable of being effectively speeded up. Accordingly, this study developed a new imaging lens of optical lens decentering inspection system by the fast, accurate and low-cost detection, to achieve a large number of batch inspections for the decentration error.
A Study on the Changes of the Polarization States in Light-Wave Systems [ 下載 PDF ]
Wu-Chi Chen, Yen-Chun Yu
Awareness of the polarization relationships within high-speed, long-distance light-wave systems is the key to successful designs. The work is motivated by the desires to explore and study the changes of the polarization states caused by the mutual interaction of the two polarization light signals. The wavelengths of the two left-hand polarization light signals were set the ranges from 1530.16 nm to 1534.04 nm. The two polarization light signals propagated through the same optical path were then multiplexed together. We saw the detection of the output polarizations with a polarimeter was mainly the left-hand polarization states. However, the right-hand polarization states of the output signals can be still discovered in the polarimetric analyzer. Other experiments with the same procedures were performed as stated above except that the wavelengths of the two right-hand polarization light signals ranged between 1535.06 nm and 1536.09 nm. Experimental observations indicate the output polarization light signals were completely the right-hand polarization states. The work demonstrated as follows, 1. The mutual interaction between the two left-hand polarization light signals can cause the important changes of the polarization states within some wavelength ranges. 2. The degree of polarization of the output signals increased as the output optical power decreased. There is a quite close inverse relationship between the degree of polarization and optical power.
Lighting Design and Prototype Measurement for LED Vehicle Daytime Running Light [ 下載 PDF ]
Yuan Chang Liou, Shin-Kuan Chen, Li-Chun Lai, Yu-Jhan Sie
The lighting design and the prototype light pattern measurement for ECE R87 vehicle daytime running light with the different LED is studied in this paper. The design methods by the direct emission and the asymmetric refl ector are adopted for the optical design, respectively; while, the ASAP software is used for the light pattern simulation and analysis. The results show that the design method is only suitable for small angle LED by the direct emission while it works for all kind of LED by the asymmetric refl ector. The prototype is manufactured for the refl ector with the Cree-xpc LED and its light pattern measurement is similar to the simulation results. Since only one LED, minimum value 80 lm and 1 watt, is needed to pass the ECE R87 regulation, that the design method by the the asymmetric refl ector is proven to be practical.
