Electrospray pyrolysis

Matsushima, Y., Y. Nemoto, T. Yamazaki, K. Maeda, and T. Suzuki. Fabrication of SnOj particle-layer on the glass substrate using electrospray pyrolysis method and the gas sensitivity for Hj. Sensors and... 

There are also other methods such as spray pyrolysis and electrospray pyrolysis besides the above method [26]. To prepare nanoparticles by spray pyrolysis, a starting solution is prepared by dissolving, usually, the metal salt of the product in the solvent. The droplets atomized from a starting solution are introduced to furnace. Drying, evaporation of solvent, diffusion of solute, precipitation, reaction of precursor, and surrounding gas, pyrolysis may occur inside the furnace before the formation of product. It is similar to spray drying except the type of precursor. For this, colloidal particles are typically used as precursors. Some products prepared by spray pyrolysis are listed in Table 34.1. 

Lenggoro IW, Okuyama K, Fernandez de la Mora J, Tohge N. Preparation of ZnS nanoparticles by electrospray pyrolysis. J Aerosol Sci 2000 31 121-36. 

The concept or the basis of spray pyrolysis method assumes that one droplet forms one product particle. To date, submicrometer- to micrometer-sized particles are typically formed in a spray pyrolysis process. A variety of atomization techniques have been used ftn- solution aerosol formation, such as ultrasonic spray pyrolysis, electrospray pyrolysis, low pressure spray pyrolysis using a filter expansion aerosol generator (FEAG), salt-assisted spray pyrolysis, two-fluid pyrolysis method, etc. [15-18]. These atomization methods differ in droplet size, rate of atomization, and... 

One of the promising methods for producing satisfied quantities of a powder with narrow size distribution and nanometric mean diameter is electrospray pyrolysis method. In this method, a meniscus of a precursor (spray solution) at the end of capillary tube becomes conical when charged to a high voltage (several kilovolts) with respect to a counter electrode. The droplets are formed by continuous breakup of a jet extending from this liquid cone, known as Taylor cone. Lenggaro, Xia, Okuyama, and Fernandez de la Mora, in their papers published from 2000 to 2003, described how this technique functions and how it is possible to measure online a size distribution of particles obtained from different types of precursor systems. For this purpose, they used differential mobihty analyzer and a condensation nucleus/particle counter (CNC/ CPC) [19-26]. 

Ultra-flne-grained highly reactive yttria powders, suitable especially for the preparation of transparent ceramics, are prepared by various methods including combustion synthesis [293], precipitation [294, 295], hydrothermal synthesis [296], electrospray pyrolysis [297], and sol-gel [298]. In order to improve the dispersion and sinterability of yttria powders, seed crystals are often added [296]. A significant refinement of yttria powders prepared by precipitation from solution may be achieved by the addition of sulfate ions to the reaction mixture [299] (Figure 1.25). 

It is therefore not surprising that the interest in PyMS as a typing tool diminished at the turn of the twenty-first century and hence why taxonomists have turned to MS-based methods that use soft ionization methods such as electrospray ionization (ESI-MS) and matrix-assisted laser desorption ionization (MALDI MS). These methods generate information-rich spectra of metabolites and proteins, and because the molecular ion is seen, the potential for biomarker discovery is being realized. The analyses of ESI-MS and MALDI-MS data will still need chemometric methods, and it is hoped that researchers in these areas can look back and learn from the many PyMS studies where machine learning was absolutely necessary to turn the complex pyrolysis MS data into knowledge of bacterial identities. 

A reevaluation of molecular structure of humic substances based on data obtained primarily from nuclear magnetic resonance spectroscopy, X-ray absorption near-edge structure spectroscopy, electrospray ionization-mass spectrometry, and pyrolysis studies was presented by Sutton and Sposito (2005). The authors consider that humic substances are collections of diverse, relatively low molecular mass components forming dynamic associations stabilized by hydrophobic interactions and hydrogen bonds. These associations are capable of organizing into micellar structures in suitable aqueous environments. Humic components display contrasting molecular motional behavior and may be spatially segregated on a scale of nanometers. Within this new structural context, these components comprise any molecules... 

Estuarine water Arsenic Inorganic, methylated and hydride refractory arsenic species Electrospray,ES-MS, pyrolysis GC-MS and HPLC-ICP-MS Identification of species Florencio et al. (1997)... 

Florencio, M.H., Duarte, M.F., Facchetti, S., Gomes, M.L., Goessler, W., Irgolic K.J., vantKlooster, HA., Montanarella, L., Ritsema, R., Boas, L.F. and de Bettencourt, A.M.M. (1997) Identification of inorganic, methylated and hydride-refractory arsenic species in estuarine waters. Advances by electrospray, ES-MS, pyrolysis-GC-MS and HPLC-ICP/MS. Analusis, 24, 226—229. 

A variety of volatilization/ionization methods have been applied to polymers a recent review or key paper is cited here for each. Extensive reviews that include mass spectrometry of pol5mrers can be found in Analytical Chemistry Other to )ical reviews are field desorption, laser desorption, plasma desorption, fast-atom bombardment, pyrolysis, and electrospray ionization. The present review will focus on polymer characterization using secondary-ion mass spectrometry (SIMS) in the high mass range comparison with other methods will be presented where appropriate. 

Liquid chromatography-electrospray ionization-time-of-flight-mass spectrometry. Pyrolysis-metastable atom bombardment-time-of-flight-mass spectrometry. 

Figure 6.36. Illustrations of apparati used in the gas-phase synthesis of 0-D nanoparticles. Shown are (a) plasma system (b) spark-facilitated growth (c) laser vaporization/pyrolysisf (d) laser evaporation (e) laser ablation (f) inert-gas evaporation " (g) electrospray system " (h) spray pyrolysis. " ...

Ion-mobility mass spectrometry (IM-MS) has emerged as an important analytical method in the last decade [74]. In IM-MS, ions are generated by pyrolysis, electrospray, laser desorption, or other ionization techniques prior to their entry into a gas-filled mobility drift cell. In this cell, ions drift at a velocity obtained from an electric field based on their shapes or dipoles in the case of differential mobility spectrometry (DMS). The greater the cross section of an analyte is (i.e., the larger the ion... 

For ambient mass spectrometric approaches, techniques such as electrospray-assisted pyrolysis ionization (ESA-Py) (Hsu et al., 2005), desorption electrospray ionization (DESl) (Takats et al., 2004), easy ambient sonic-spray ionization (EASl) (Haddad et al., 2008), and atmospheric pressure laser-induced acoustic desorption chemical ionization (AP/LIAD-CI) (Nyadong et al., 2011) have been used for the direct analysis of crude oil with minimal sample pretreatment. Such approaches prevent unexpected effects on the composition of crude oil samples during preparation. Another attractive feature of performing analyses imder ambient conditions is the capacity for rapid sampling, thereby enabhng opportunities for high-throughpnit analysis. 

Electrospray-assisted pyrolysis ionization ESA-FY Ambient Polar Hsu et al. 

Electrospray-assisted pyrolysis ionization/mass spectrometry (ESA-Py/MS) for crude oil analysis... 

To characterize polymers and trace polar components in crude oil samples, we previously developed an interface to combine electrospray ionization mass spectrometry (ESI/MS) with a pyrolytic probe. This technique successfully detects the polar pyrolysates that are released from synthetic polymers, which are constructed from polar units and crude oil. We refer to this technique as "electrospray-assisted pyrolysis ionization/ mass spectrometry (ESA-Py/MS)" (Hsu et al, 2005 200. ... 

Hsu, H.J. Oung, J.N. Kuo, T.L. Wu, S.H. Shiea, J. (2007), Using electrospray-assisted pyrolysis ionization/mass spectrometry for the rapid characterization of trace polar components in crude oil, amber, humic substances, and rubber samples. Rapid Communications in Mass Spectrometry, Vol.21, No.3, pp. 375-384, ISSN 1520-6882. 

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