Wireless Data Acquisition of Transient Signals for Mobile Spectrometry Applications

Abstract

Wireless data acquisition using smartphones or handhelds offers increased mobility, it provides reduced size and weight, it has low electrical power requirements, and (in some cases) it has an ability to access the internet. Thus, it is well suited for mobile spectrometry applications using miniaturized, field-portable spectrometers, or detectors for chemical analysis in the field (i.e., on-site). There are four main wireless communications standards that can be used for wireless data acquisition, namely ZigBee, Bluetooth, Wi-Fi, and UWB (ultra-wide band). These are briefly reviewed and are evaluated for applicability to data acquisition of transient signals (i.e., time-domain) in the field (i.e., on-site) from a miniaturized, field-portable photomultiplier tube detector and from a photodiode array detector installed in a miniaturized, field-portable fiber optic spectrometer. These are two of the most widely used detectors for optical measurements in the ultraviolet-visible range of the spectrum. A miniaturized, 3D-printed, battery-operated microplasma-on-a-chip was used for generation of transient optical emission signals. Elemental analysis from liquid microsamples, a microplasma, and a handheld or a smartphone will be used as examples. Development and potential applicability of wireless data acquisition of transient optical emission signals for taking part of the lab to the sample types of mobile, field-portable spectrometry applications will be discussed. The examples presented are drawn from past and ongoing work in the authors' laboratory. A handheld or a smartphone were used as the mobile computing devices of choice.

Microfluidics and Nanofluidics: Science, Fabrication Technology (From Cleanrooms to 3D Printing) and Their Application to Chemical Analysis by Battery-Operated Microplasmas-On-Chips

“…It is envisioned that future fluidics (Figure 1) will be embedded within portable micro-or nano-instruments for measurements on-site (i.e., in the field). Such instruments will have (some) energy autonomy [198][199][200], will incorporate some "smarts" [201] (e.g., based on Artificial Intelligence and Deep Learning) and will have wireless capability [202] so that they can become a part of the Internet of Things (IoT) [200][201][202][203]. Clearly, fluidics (e.g., milli-, micro-or nano-) have the potential to become critical components of mobile (or even wearable) instruments that are "cheap, smart and under wireless control" [139].…”

Artificial Neural Networks (ANNs) for Spectral Interference Correction Using a Large-Size Spectrometer and ANN-Based Deep Learning for a Miniature One

“…We have been developing and characterizing miniaturized plasmas in the form of microplasmas [41][42][43][44][45][46][47][48] that we fabricated using a variety of fabrications technologies [49][50][51][52] for taking part of lab to the sample types of applications [53][54][55][56][57][58][59][60]. Microplasmas are arbitrarily defined as those with one critical dimension in the micrometer regime.…”

Computational Fluid Dynamics (CFD) Applied to a Glass Vaporization Chamber for Introduction of Micro- or Nano-Size Samples into Lab-Based ICPs and to a CFD-Derived (and Rapidly Prototyped Via 3D Printing) Smaller-Size Chamber for Portable Microplasmas

“…We have been characterizing them [24][25][26][27][28][29][30][31][32][33][34][35], primarily for "taking part of the lab to the sample" types of applications, i.e., for analytical measurements on-site. Future microplasmabased spectrometers are envisioned to have wireless capability [36,37] and (some) energy autonomy [38][39][40][41][42]. In contrast to ICPs, low gas consumption (e.g., 250 mL/min) and lowpower requirements (e.g., ~10 W) are key characteristics of microplasmas.…”