Forensic Science Instrumentations and Application

Examination Methods for Biological Samples of Forensic Medicine [ 下載 PDF ]

Chao-Ching Huang, Chun-Yen Lin, Chun-Sin Lin, Tsun-Ying Huang, Chiao-Hsuan Yuan, James Chun-I Lee

Locard's exchange principle states that every contact leaves a trace. Therefore, there could be biological evidence left during assault or sexual crime, and fluids or hairs could also be seen in residential burglary cases. Furthermore, body parts of remains may be linked to a victim. Diatom identification from body's lung tissue or sphenoid sinus fluid is a key evidence of drown or foul play in death investigation. We perform specific ways to find possible biological evidence, and molecular biology techniques are often used. Its high degree of accuracy will improve the quality of criminal justice. This report provides common examination methods for biological samples of forensic medicine to demonstrate the reliability of scientific evidence.

Applications of Scanning Electron Microscopy/ Energy Dispersive X-Ray Spectrometry to Forensic Examination of Trace Evidence [ 下載 PDF ]

Hsien-Hui Meng

Scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS) is a well developed analytical method. SEM/EDS's capability to simultaneously perform morphological and multi-elemental analysis of trace evidence leads to its extensive application in forensic examination of physical evidence. Herein, we briefly described application cases such as gunshot residues, pyrotechnics deflagration residues, trace evidence on fired bullets, stick welding residues, disc grinder residues, and lighter flint residues by SEM/EDS forensic examination.

Application of Vacuum Metal Deposition to Latent Fingerprint Development [ 下載 PDF ]

Chin-Min Chen, Kuang-Chuan Wang, Jeh-Shane Liao, Sheaw-Guey Cheng

Vacuum metal deposition (VMD) techniques, well established and mature in Taiwan, are commonly used in nanooptoelectronics industry and in the surface treatment of commodities for both beautification and functionality purposes. Owing to the micro-structural differences between an object surface and the fingerprint residues left on it, and hence the different coating environments, the surface-specific VMD can be used to develop the individually unique latent fingerprints. In order to have the VMD techniques successfully applied in our country's latent fingerprint development and to promote the level of the specialty of our country, we have set up a homemade fingerprinting VMD equipment in our lab under a cooperation agreement with the Department of Materials Science and Engineering, National Taiwan University of Science and Technology (NTUST). The interdisciplinary collaborative project has been accomplished with the following achievements:establishment of the first forensic VMD equipment in Taiwan and its high performance in latent fingerprint development (which has in turn enhanced our ability in fingerprint identification), establishment of the methods for developing latent fingerprints on ordinary and special surfaces, optimization of experimental conditions for latent fingerprint development, standard operation procedures made available, etc.

Application of Chromatography with Mass Spectra for Analyzing Emerging Drugs of Abuse [ 下載 PDF ]

Sheng-Meng Wang, Sin-Yi Lai, Chih-Yueh Wei, Wei-Cheng Huang

In this study, GC/MS and LC/MS analyses of emerging drugs are evaluated and validated. There are only limited literature and few data available, and this study has been engaged in establishing relevant methodologies and database, including mass spectra of different derivatives, molecular weight and selection of qualifier/quantifier ions. It is helpful to identify the emerging drugs, to realize the tendency of emerging drugs and to prevent the spread of emerging drugs.

The Applications and Perspective of Stable Isotope Ratio Mass Spectrometer on Forensic Science [ 下載 PDF ]

Chao-Hsin Cheng, Nai-Jung Wan, San-Chong Chyueh

Isotope ratio mass spectrometer (IRMS) is a powerful analytical instrument applied on many fields like geology, oceanography, environmental changes, environmental pollution, medical science, drug testing, agriculture, ecology and forensic science. We introduce the theory and operational modes of IRMS in this article, including the sampling interface: dual inlet and continuous flow, and the options: EA, TC EA, GC, HPLC, gas bench and preconcentration, and the mass spectrometer: ion source, mass analyzer and detector. We also discuss IRMS applications on forensic science.

Nanomaterials and Mass Imaging for Forensic Analysis of Latent Fingerprints [ 下載 PDF ]

Yong-Chien Ling, Shiou-Ling Lei

The rapid development of nanomaterials (NMs) and mass imaging (MI) leads to their applications for forensic identification of latent fingerprints (LFPs) in forensic science. Herein, we briefly introduce the chemical composition of LFPs and commonly used visualization techniques for LFPs first, followed by demonstrating the operational principles and current application status of utilizing NMs and MI to enhance visualization extent and to generate chemical images from LFPs, respectively.

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Latest Advance in Ultrahigh Resolution Full-Field X-Ray Microscopy [ 下載 PDF ]

Yeu-Kuang Hwu, Yu-Sheng Chen, Cheng-Hung Lin, Shih-Sian Yang, Ching-Kuo Chen, Chang-Hai Wang, Hsien-Tse Tung

Contemporary X-ray microscopy has evolved into the 'Nano' age thanks to the development of advanced nanodevice fabrication and elegant integration of traditional optic concepts. This article reviews the latest advance of fabrication of X-ray optic components and the next-generation ultrahigh resolution X-ray microscopy. Specifically, hard X-ray Fresnel zone plates with the highest aspect ratio in the world have been produced by e-beam lithography and micro scale electro-deposition. The state-of-the-art synchrotron X-ray based hard X-ray microscopes have demonstrated a resolution better than 20 nm. Ultrahigh spatial and temporal resolutions, combined with sufficient phase contrast make hard X-ray microscopes powerful tools to resolve three-dimensional structure at the nanoscale. This new characterization methodology opens new opportunities in multiple research fields such as biology, nanomedicine, and material sciences.

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Building Electronic Circuits Using Liquids: Ionic Liquid Eelctrofl uidic Circuit Microfl uidic Pressure Sensors [ 下載 PDF ]

Yi-Chung Tung

This article introduces a microfluidic pressure sensor based on electrofluidic circuits constructed by ionic liquid (IL)-filled microfluidic channels. The developed pressure sensor can be seamlessly fabricated into polydimethylsiloxane (PDMS) microfluidic systems using the well-developed multilayer soft lithography (MSL) technique without additional assembly or sophisticated cleanroom microfabrication processes. As a result, the device can be easily scaled up and is fully disposable. The pressure sensing is achieved by measuring the pressure-induced electrical resistance variation of the constructed electrofluidic resistor. In addition, an electrofluidic Wheatstone bridge circuit is designed for accurate and stable resistance measurements. The pressure sensor is characterized using pressurized nitrogen gas and the experimental results demonstrate the great long-term stability, temperature stability, and linear characteristics of the developed pressure sensing scheme. Consequently, the integrated microfluidic pressure sensor developed in this paper is promising for better monitoring and for characterizing the flow conditions and liquid properties inside the PDMS microfluidic systems in an easier manner for various applications.

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Power Control Distribution Unit Protection Circuit Design of FORMOSAT-5 Satellite [ 下載 PDF ]

Che-Cheng Huang, Jia-Jing Yeh

The power control and distribution unit (PCDU) in FORMOSAT-5 satellite, acts as the satellite power and allocation center, similar to human heart. The main functions are to condition energy from the solar arrays and distribute power for all subsystems on the satellite. The PCDU's protection circuits provide monitoring and isolation according to voltage and current of internal circuit system and external power users. The voltage protection circuits are undervoltage-lockout (UVLO) detector for the main bus, over voltage (OV) detector for satellite battery, and under voltage (UV) protector for DC-DC converters. The portion of current protection circuit is over current (OC) protector for external power users and DC-DC converter system. This paper describes protection working methods and the reliable circuit design implementation.