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Pottery excavated from the archeological UNESCO world heritage site Ban Chiang in Thailand stem from distinct periods. Black vessels with cord-mark design from Pre-metal Age (ca. 3000–1000 BC), Bronze Age pottery (ca 1000–300 BC) with yellow-brown surface and Iron Age samples (ca. 300 BC–200 AD) with red pictorial surface patterns. In a previous work [Bismayer U., Srilomsak S., Treekamol Y., Tanthanuch W., Suriyatham K. Artefacts from Ban Chiang, Thailand: pottery with hematite-red geometric patterns. Z. Kristallogr. 2020, 235, 559–568] we studied the mineralogical composition and their surface colour materials of shards from Bronze and Iron Age. In this work we focus on bulk features of the dark Pre-metal Age cord-marked ceramic shard PSN2-S10E13 and compare its elemental and mineralogical composition with bulk composition of sample 5412-S6E15 from Bronze Age. Experimental techniques are electron microprobe, X-ray powder diffraction, FTIR spectroscopy, optical microscopy and X-ray tomographic microscopy (XTM). Sample PSN2-S10E13 contains more quartz than 5412-S6E15. In the bulk of the Pre-metal Age shard, diffraction signals of mullite occur, indicating higher firing temperatures compared to the younger sample. Phyllosilicate signals are seen in FTIR spectra of both shards. E-modes of quartz dominate FTIR spectra of both samples. Optical thin sections show voids around micro-particles in PSN2-S10E13 and XTM indicates that the pore volume percentage of sample PSN2-S10E13 is higher than in 5412-S6E15. Because of the large age gap to younger samples from Ban Chiang, the proper age of our oldest sample PSN2-S10E13 was determined using an accelerator mass spectrometer (AMS) by simultaneous 14C/12C and 13C/12C isotope ratio measurements which yielded a radiocarbon age of 3609 ± 29 BP (resp. 1659 ± 29 BC). [ABSTRACT FROM AUTHOR]

The inner diameter measurement of the micro-hole was performed by a tactile microprobing system using a method of the local surface interaction force detection. The inner diameter of the micro-hole was calculated by the least square method based on the probing coordinates obtained by a custom-made micro-coordinate measuring machine. The dispersion of the probing coordinates was investigated by changing the probe approaching direction with respect to the normal direction of the inner side of the micro-hole. During the probing inside the micro-hole, it was confirmed that the dispersion of the probing coordinates increased when the disagreement between the probe approaching direction and the normal direction of the micro-hole at the measured point became large. The influence of the dispersion of the probing coordinates was evaluated through the uncertainty analysis of the inner diameter measurement. It was revealed that the uncertainty of the inner diameter measurement could be improved when limiting the disagreement between the probe approaching direction and the normal direction of the micro-hole to within ±pi/4 rad. [ABSTRACT FROM AUTHOR]

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Direct sampling of lipids from tissues for direct mass spectrometry (MS) analysis allows a quick profiling of lipidome, which is important for biomedical applications. In this work, we developed a polyporous polymeric membrane (PPM) microprobe for highly efficient sampling of lipids directly from tissue samples. The PPM was prepared by polypropylene with pores as large of 10 ​μm, facilitating the permeation of lipids from tissue surfaces. The PPM was coated onto a stainless steel wire with a thickness of ∼100 ​μm. The entire analysis procedure includes sampling of the lipids in tissue, washing the probe, and extraction spray ionization for MS analysis. The effectiveness was validated by analyzing mouse brain tissue samples. It showed high recoveries for a series of lipid classes in comparison with total lipid extraction method. Further demonstration was carried out with analysis of tissue samples from mouse liver, stomach, kidney and legs. With high physical strength and good chemical stability, the microprobe was also demonstrated for sampling lipids inside mouse kidney tissue samples. By incorporating a photochemical derivatization, a workflow was also developed for fast detection of lipid CC isomers in tissue samples. Finally, a microprobe array was also developed for simultaneous sampling of lipids from multiple sites on tissue surfaces.

Metabolomics is one of the leading approaches for understanding the toxic-mode-of-action of environmental contaminants. Nuclear Magnetic Resonance (NMR) spectroscopy has been commonly used in metabolomic studies; however, its main drawback is its relatively low sensitivity, making it challenging to study mass limited but environmentally crucial samples. In this work a 1 mm microlitre probe modified with a separate lock chamber to address this challenge, provided substantial improvements in mass sensitivity relative to conventional 5 mm NMR probes. The 1 mm probe is used to analyze various components of the model organism Daphnia magna, including hemolymph, parthenogenetic eggs, dormant eggs, and neonates. A μL volume flow system is designed for the 1 mm probe to perform an in-vivo exposure of neonates to high salt concentrations. The metabolic investigation of these samples was only achieved due to the minimum sample requirements and high salt tolerance of the probe, demonstrating that the 1 mm microlitre probe modified with a separate lock chamber holds significant potential for future metabolomic studies of mass limited samples.

The use of the field emission gun in scanning electron microscopy permits the imaging of sub-micrometer-size features. However, achieving sub-micrometer analytical spatial resolution in electron probe microanalysis (EPMA) requires both reducing the electron beam size and reducing the accelerating voltage to achieve the desired sub-micrometer interaction volume. The resulting quantification of the first-row transition metals at low accelerating voltage, i.e., below 7–8 kV, is problematic as the main characteristic X‑ray lines (Kα) cannot be excited at these conditions. Furthermore, the use of the Lα and Lβ soft X‑ray lines for quantification is complicated by bonding and self-absorption effects resulting in not-yet-determined mass absorption coefficients and hence in the failure of the traditional matrix correction procedure. We propose two methods to circumvent these low-kilovolt (low-kV) analysis limitations: using the non-traditional FeLℓ line and using universal calibration curves for the more traditional FeLα and Lβ lines. These methods were successfully applied to Fe-sulfide minerals showing accurate quantification results by EPMA at reduced kV, necessary for accurate quantification of sub-micrometer sulfide grains. [ABSTRACT FROM AUTHOR]

Potential human health and environmental issues associated with aerosol release as a result of biomass pyrolysis have received a widespread attention. Accurate aerosol sampling at source can help to unravel the complex mechanisms involved. This paper describes a novel aerosol microprobe sampling system combined with a smoking cycle simulator and a differential mobility spectrometer (microprobe-SCS-DMS) for spatially resolved in-situ characterization of aerosol release inside a heated tobacco product. A purposely made microprobe was accurately positioned to sample the aerosol generated at different positions within the heated distillation and pyrolysis zone. The aerosol particle behaviour at source was studied under a combined heating and air-flow cycle. Detailed measurements on the aerosol formed from both the axial and radial directions inside the heated tobacco rod were obtained, including the aerosol particle size distribution, particle number concentration, and particle volume concentration during external air flow perturbation. The results provided detailed information on the formation, diffusion, transfer and filtration of the aerosol which would otherwise not be possible. The microprobe-SCS-DMS system described in this work could be useful for other similar challenges involving aerosol in-situ characterization. • A novel aerosol microprobe sampling system was combined with a fast particulate spectrometer. • Spatially resolved in-situ characterization of aerosol release inside a heated tobacco product was obtained. • In-situ aerosol mapping provided detailed information on the formation of aerosol during tobacco distillation and pyrolysis [ABSTRACT FROM AUTHOR]

Direct sampling of lipids from tissues for direct mass spectrometry (MS) analysis allows a quick profiling of lipidome, which is important for biomedical applications. In this work, we developed a polyporous polymeric membrane (PPM) microprobe for highly efficient sampling of lipids directly from tissue samples. The PPM was prepared by polypropylene with pores as large of 10 ​μm, facilitating the permeation of lipids from tissue surfaces. The PPM was coated onto a stainless steel wire with a thickness of ∼100 ​μm. The entire analysis procedure includes sampling of the lipids in tissue, washing the probe, and extraction spray ionization for MS analysis. The effectiveness was validated by analyzing mouse brain tissue samples. It showed high recoveries for a series of lipid classes in comparison with total lipid extraction method. Further demonstration was carried out with analysis of tissue samples from mouse liver, stomach, kidney and legs. With high physical strength and good chemical stability, the microprobe was also demonstrated for sampling lipids inside mouse kidney tissue samples. By incorporating a photochemical derivatization, a workflow was also developed for fast detection of lipid C[bond, double bond]C isomers in tissue samples. Finally, a microprobe array was also developed for simultaneous sampling of lipids from multiple sites on tissue surfaces., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors. Published by Elsevier Ltd.)

Synthetic single crystal diamond grown using the chemical vapor deposition technique constitutes an extraordinary candidate material for monitoring radiation in extreme environments. However, under certain conditions, a progressive creation of space charge regions within the crystal can lead to the deterioration of charge collection efficiency. This phenomenon is called polarization and represents one of the major drawbacks associated with using this type of device. In this study, we explore different techniques to mitigate the degradation of signal due to polarization. For this purpose, two different diamond detectors are characterized by the ion beam-induced charge technique using a nuclear microprobe, which utilizes MeV energy ions of different penetration depths to probe charge transport in the detectors. The effect of polarization is analyzed by turning off the bias applied to the detector during continuous or discontinuous irradiation, and also by alternating bias polarity. In addition, the beneficial influence of temperature for reducing the effect of polarization is also observed. Finally, the effect of illuminating the detector with light is also measured. Our experimental results indicate that heating a detector or turning off the bias, and then applying it during continuous irradiation can be used as satisfactory methods for recovering the CCE value close to that of a prepolarized state. In damaged regions, illumination with white light can be used as a standard method to suppress the strength of polarization induced by holes. [ABSTRACT FROM AUTHOR]