Portable Systems for Energy‐Dispersive X ‐Ray Fluorescence Analysis

Abstract

Portable energy‐dispersive X‐ray fluorescence (EDXRF) spectrometers are very useful and popular in many fields for the on‐site analysis of elements because EDXRF is a nondestructive, multielemental, and inexpensive technique that is extremely well suited for the analysis of inorganic materials. An EDXRF spectrometer mainly consists of an X‐ or γ‐ray excitation source, an X‐ray detector with electronics, and a pulse‐height analyzer. Recent technological developments have resulted in small, low‐power, dedicated X‐ray tubes; thermoelectrically cooled semiconductor detectors; and small pulse‐height analyzers. Therefore, completely portable EDXRF spectrometers are available that can be assembled on‐site, with the size of a book and a weight that is as light as 300 g (using an X‐ray tube) or less (using a radioactive source). These spectrometers can be employed for on‐site analysis in various fields, such as works of art, alloys, soil, environmental samples, forensic medicine, paper, waste materials, mineral ores and their products, or anywhere a portable apparatus would be required. This article reviews the present status of the development and application of portable EDXRF systems. The various components of a portable system are described, including the radiation source, i.e. small, low‐power, dedicated X‐ray tubes, or, alternatively, radioactive sources that emit X‐rays or low‐energy γ‐rays, and X‐ray detectors, i.e. semiconductor detectors, with a special emphasis on the more recent thermoelectrically cooled X‐ray detectors (Si‐Positive–Intrinsic–Negative [Si‐PIN], Si‐drift detector (SDD), CdTe, HgI 2 , and others). Commercial systems are considered, and the most common and significant applications are described, with particular emphasis on the analysis of works of art.

X-Ray Fluorescence Analysis in Biology and Medicine

“…Динамичное развитие характерно для детекторов с термоэлектрическим охлаждением [11,15,16], РФА с полным внешним отражением (РФА с ПВО) [11,15,[17][18][19][20][21][22] и с поляризацией излучения [23][24][25][26][27][28]. При исследовании разнообразных биологических материалов широко применяются удобные портативные энергодисперсионные рентгенофлуоресцентные (ЭДРФА) спектрометры ряда фирм [29][30][31]. Конструирование и массовое производство портативных спектрометров стало возможным после усовершенствования детекторов с термоэлектрическим охлаждением: кремний дрейфовых детекторов (silicon drift detectors , SDD) и PIN диодов и решением технологических проблем, связанных с выпуском небольших маломощных рентгеновских трубок с воздушным охлаждением [11,32].…”

Identifying the Unknown Content of an Ancient Egyptian Sealed Alabaster Vase from Kha and Merit’s Tomb Using Multiple Techniques and Multicomponent Sample Analysis in an Interdisciplinary Applied Chemistry Course

“…In the last decades, a huge increase of the methodologies and techniques in chemistry to support the studies of the archeologists was observed. − Cultural heritage objects can be unique and irreplaceable, and every time, the approach needs to be adapted to the specific case study. The best practices in this field should follow a Standard Operating Procedure (SOP), − which plan the use of the techniques of analysis as a function of the goal of the investigation. The SOP provides the necessary guidance because a multianalytical noninvasive and microinvasive approach to a work of art implies a number of tasks with a strict order of compilation, which is strictly related the kind of information that is possible to gather from each analysis.…”