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In this work, paper spray (PS) is combined with atmospheric pressure photoionization-mass spectrometry (PS-APPI-MS) for the determination of non-polar and low polar compounds, such as the neutral per- and polyfluorinated alkyl substances (PFAS). The proposed PS-APPI-MS method has been developed for the analysis of fluorotelomer alcohols (FTOHs), fluoroctanesulfonamides (FOSAs) and fluorooctane sulfonamido-ethanols (FOSEs), using both negative ion mode and high-resolution mass spectrometry (HRMS). The most critical working parameters (i.e., UV-krypton lamp position, sample drying time, spray dopant solvent and spray voltage) have been evaluated to study both the ionization behaviour and ionization efficiency. The best results were achieved using dopant-assisted PS-APPI-HRMS with toluene as dopant solvent. The most intense ions observed in the mass spectra, [M‒H] ‒ for FOSAs and [M+O 2 ] ‒• for FTOHs and FOSEs, were selected and proposed for fast screening and quantitative analysis of target compounds in waterproof impregnation sprays samples using internal standard calibration method and being able to detect down to μg L -1 levels. The satisfactory values of the method quality parameters (detection capability, repeatability, trueness and linearity) demonstrated the good performance of the PS-APPI-HRMS method and allowed the identification and quantitation of some FTOHs (6:2 FTOH, 7-Me-6:2 FTOH, 8:2 FTOH, 10:2 FTOH) and N-MeFOSE at mg L -1 in some of the waterproof impregnation spray products analyzed. This low-cost PS-APPI-HRMS method allows a fast screening, with minimum sample preparation, of non-polar and low polar compounds simultaneously, which can significantly improve the throughput on routine laboratories., Competing Interests: Declaration of competing interest 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., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Purpose: The surface energy of the printing material can be increased to desired levels with different chemicals or methods. However, the important thing is that the surface properties of printing material are not affected negatively. In this way the aim of this paper provide that the surface properties of matte and glossy coated paper is improved by the argon containing atmospheric pressure plasma device because the plasma treatment method does not occur surface damaging on the papers. Design/methodology/approach: In experimental studies, test samples cut from 160 mm × 30 mm in size from 115 g/m2 gloss- and matt-coated papers were used. The plasma treatments of paper samples were carried out with an argon containing atmospheric pressure plasma device of laboratory scale that produces plasma of the corona discharge type at radio frequency. The optimized plasma parameters were at a frequency of 20 kHz and plasma power 200 W. A copper electrode of length 12 cm and diameter 2.5 mm was placed in the centre of the nozzle. Findings: Research findings showed that the surface energies of the papers increased with the increase in plasma application time. While the contact angle of the untreated glossy paper is 82.2, 8 second plasma applied G3 sample showed 54 contact angle value. Similarly, the contact angle of the base paper of matt coated is 91.1, while M3 is reduced to 60.4 contact angles by the increasing plasma time. Originality/value: Plasma treatment has shown that no chemical coating is needed to increase the wettability of the paper surface by reducing the contact angle between the paper and the water droplet. In addition, the surface energies of all papers treated by argon gas containing atmospheric pressure plasma, increased. Plasma treatment provides to improve both the wettability of the paper and the adhesion property required for the ink, with an environmentally friendly approach. [ABSTRACT FROM AUTHOR]

Ambient ionization mass spectrometry (AIMS) has been developing explosively since its first debut. The ionization process was hence able to be achieved under atmospheric pressure, facilitating on-site field analysis in a variety of areas, such as clinical diagnosis, metabolic phenotyping, and surface analysis. As part of the ambitious goal of making MS a general device that can be used in everyday life, lots of efforts have been paid to miniaturize the ionization source. This review discusses avant-garde sources that could be entirely hand-held without any accessories. The structure and applications of the devices are described in detail as well. They could be expediently used in real-time and on-site analysis, presenting a great future potential for the routinizing of MS., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

This study demonstrates a method for patterning paper-based microfluidic devices. An octadecyltrichlorosilane (OTS) solution is used to coat a chromatography paper to make it hydrophobic. A low-temperature (~ 32.9 °C) atmospheric-pressure dielectric-barrier-discharge jet with a shadow mask is then used to pattern hydrophilic stripes on the OTS-coated hydrophobic paper. In this manner, 1-mm-wide hydrophilic stripes are patterned successfully. Liquids are demonstrated to be transported and mixed in the hydrophilic stripes. Water contact angle measurement, X-ray photoelectron spectroscopy, surface profiler, optical emission spectroscopy, and scanning electron microscopy are used to characterize effect of pattering. [ABSTRACT FROM AUTHOR]

Cultural heritage conservation extends beyond individual interests, therefore preserving patrimony artworks is a timeless endeavor. This study proposes cold atmospheric plasma as a suitable method for the treatment of paper, deteriorated by cellulolytic bacteria. Three distinct methods of treating Bacillus velezensis isolated herein from an artificially deteriorated book were applied using cold atmospheric plasma. Bacteria were cultivated on membranes, in liquid media, and directly on paper. When used for five minutes at a power of 50 W and a current density of 12 mA/cm2, the designed cold atmospheric plasma device proved successful in preventing bacterial growth and spore formation. B. velezensis spore generation is a rare mechanism that has never been observed within these circumstances before. Moreover, the cold atmospheric plasma device can suppress the development of cellulolytic bacteria without damaging the paper substrate, which is a significant step in the preservation of patrimony artworks. [ABSTRACT FROM AUTHOR]

The aim of this work was the wettability improvement of clay‐coated paper by ambient air plasma exposure. Industrial corona with a volume dielectric barrier discharge in cylindrical configuration was used as a plasma source; the exposure times varied from 0.25 up to 5 s. Water contact angle (WCA) measurement and surface free energy (SFE) evaluation were carried out for the estimation of wettability changes. Plasma treatment in the duration of 0.25 s was sufficient to decrease the WCA almost to the half of the original value, which was 76°. SFE of paper has increased by 40%–50% after plasma treatment. Long‐term ageing effect study of treated samples was carried out up to 3 months after the treatment. WCA did not reach the original value even after 3 months, and it was still 20%–30% lower. O/C ratio increased from 0.7 to 1.8 in case of 5‐s plasma treatment, and the new chemical bonds (C=O, O–C=O) were created on the surface. [ABSTRACT FROM AUTHOR]

Currently available European Alpine Altitude Climate Treatment (AACT) programs combine the physical characteristics of altitude with the avoidance of environmental triggers in the alpine climate and a personalized multidisciplinary pulmonary rehabilitation approach. The reduced barometric pressure, oxygen pressure, and air density, the relatively low temperature and humidity, and the increased UV radiation at moderate altitude induce several physiological and immunological adaptation responses. The environmental characteristics of the alpine climate include reduced aeroallergens such as house dust mites (HDM), pollen, fungi, and less air pollution. These combined factors seem to have immunomodulatory effects controlling pathogenic inflammatory responses and favoring less neuro‐immune stress in patients with different asthma phenotypes. The extensive multidisciplinary treatment program may further contribute to the observed clinical improvement by AACT in asthma control and quality of life, fewer exacerbations and hospitalizations, reduced need for oral corticosteroids (OCS), improved lung function, decreased airway hyperresponsiveness (AHR), improved exercise tolerance, and improved sinonasal outcomes. Based on observational studies and expert opinion, AACT represents a valuable therapy for those patients irrespective of their asthma phenotype, who cannot achieve optimal control of their complex condition despite all the advances in medical science and treatment according to guidelines, and therefore run the risk of falling into a downward spiral of loss of physical and mental health. In the light of the observed rapid decrease in inflammation and immunomodulatory effects, AACT can be considered as a natural treatment that targets biological pathways. [ABSTRACT FROM AUTHOR]

Nowadays, due to environmental pollution and natural energy consumption caused by waste paper, many researches are being conducted on the reuse of printed-paper. To recycle the paper, de-inking has to be performed. In this article, in order to reduce the use of the commonly used de-inking chemicals, the effect of an atmospheric pressure helium plasma treatment on the de-inking enhancement of printed-paper is studied. Through colorimeter and UV-visible spectrometer measurements the plasma treatment is shown to speed up the de-inking. While SEM observations and FTIR measurements suggest that the paper quality is retained upon plasma treatment, the increase of surface hydrophilicity measured by water contact angle measurements, compared to non-treated paper, is believed to enhance the fiber swelling of the paper and lead to a faster ink removal. [ABSTRACT FROM AUTHOR]

A sharp metal needle used as the ionization emitter in conventional atmospheric pressure chemical ionization (APCI) mass spectrometry (MS) is usually required for analyte ionization through corona discharge (i.e., gas discharge). Nevertheless, we herein demonstrate that an insulating fiber (tip diameter: 10-60 µm; length: ~ 1 cm) made of glass or bamboo can function as an APCI-like ionization emitter. Although no direct electric contact is made on the fiber, the ionization of volatiles and semi-volatiles occurs when the fiber is placed close (~ 1 mm) to the inlet of the mass spectrometer. No analyte ion signals can be observed without placing the insulating fiber in front of the mass spectrometer. The generation of ion species mainly relies on the electric field provided by the mass spectrometer. Presumably, owing to the high electric field provided by the mass spectrometer, the dielectric breakdown voltages of gas molecules in the air and the fiber are overcome, leading to the ionization of analytes in gas phase. In addition, the insulating fiber can function as a holder for sample solutions. Electrospray ionization-like processes derived from polar analytes such as amino acids, peptides, and proteins can readily occur when the insulating fiber deposited with a sample droplet is placed close to the inlet of the mass spectrometer. The feasibility of using the current approach for the detection of nonpolar and polar analytes from complex fetal bovine serum samples without tedious sample pretreatment is demonstrated in this work. The main advantage of using the suggested fiber is that the fiber can be used as the sampling probe to pick up samples and placed in front of a mass spectrometer for direct MS analysis. The application of using a robust, insulating, and disposable probe to pick up samples from real samples such as onion, honey, and pork samples followed by direct MS analysis is also demonstrated., (© 2022. Springer-Verlag GmbH Germany, part of Springer Nature.)

Due to the surface hydrophobicity, the absorbing effect of the tobacco extract droplets on the reconstituted tobacco paper is unsatisfactory. Therefore, the surface property regulation of the tobacco paper has gained increasing attention. This work reports a novel argon (Ar) plasma treatment technique for improving the surface hydrophilicity and bacteriostatic effect of the paper. Firstly, Ar plasma was selected as the treatment gas and its improving effect was demonstrated through studying the contact angle changes of water droplet on the A4 paper. Then, the capillary fibers on the paper were bombarded by Ar plasma jet. The extract droplet contact angle on the reconstituted tobacco paper-15 s surface is only 14.6° within 1 s. In comparison to the pristine paper (5.9°/s), the absorption dynamic of the droplet increased to as high as 62.5°/s, which indicated the hydrophilicity was greatly improved by the Ar plasma method. The mechanism for improving the surface hydrophilicity of the cellulose in the tobacco paper also contributed to the generation of holes by Ar plasma jet, which increased the surface permeability of cellulose. At last, Ar plasma treatment showed excellent bacteriostatic effect, which could effectively inhibit the propagation and growth of fungi, Escherichia coli, and Staphylococcus aureus on the tobacco paper. [ABSTRACT FROM AUTHOR]

Reactive ionization with atmospheric pressure ionization (API) methods have been utilized for mass spectrometry (MS) to enhance ionization efficiency of an analyte, to recognize a specific functional group of an analyte, and to investigate reaction pathways or intermediates for a certain in situ reaction. Paper spray ionization (PSI) is one of the major API techniques for reactive ionization. In reactive PSI, one of the reactants is usually spotted onto a paper tip and the other reactant is delivered through a spraying solution. After in situ reaction, reaction products are transported to the end of the tip and ionized. In this study, we investigated reactions between isothiazolinones (ITs) and cysteamine (CA) by reactive PSI MS. An IT is a heterocyclic compound that has a conjugated ketone moiety and used as a biocide or a preservative. CA is a stable aminothiol that is often used as a bifunctional covalent modifier. Through reactive PSI MS of ITs with CA, we found that a covalent modification of an IT by CA was possible and sensitivities for ITs were improved compared to conventional PSI MS of ITs that did not employ CA. In addition, possible reaction pathways between ITs and CA during reactive PSI were suggested although we could not confirm a specific reaction pathway in the current study. [ABSTRACT FROM AUTHOR]

Superhydrophobic and to some extent oleophobic paper surfaces are prepared using atmospheric pressure plasma etching. A novel dielectric barrier discharge operating in helium-oxygen mixture is used to rapidly etch organic material from paper surface and create hierarchical topography and subsequently a thin fluorocarbon film is deposited to modify the surface energy. The enhancement of surface topography is achieved via the selective removal of organic matter over inorganic calcium carbonate (calcite) fillers that co-exist in paper. The process led to the fabrication of roll-off superhydrophobic paper with water contact angles >150° and hysteresis <10° for all samples treated over 2 min with no deterioration of paper quality. Further treatment over 8 min resulted also in diiodomethane repellent surfaces. [ABSTRACT FROM AUTHOR]

• Nanogel particles are deposited onto carbon paper by a spray coating method. • CO 2 adsorption-desorption experiments are performed in a milli-channel reactor. • The adsorbent exhibits fast CO 2 adsorption rate and desorption rate. • The adsorbent presents good stability under wet conditions. In this work, we report a proof-of-concept study on CO 2 adsorbents synthesized by a thermally initiated free-radical copolymerization and then coated onto carbon paper and poly tetra fluoroethylene via a spray coating approach. A milli-channel reactor was employed to support the obtained materials for efficient CO 2 capture with wet conditions, short cooling and heating cycles (303–348 K). CO 2 uptake and release performance of the materials were measured and compared with that of the polyamine-based materials prepared by other methods. CO 2 adsorption and desorption kinetics can be greatly enhanced when using the spray coating approach, especially for carbon paper as supporter. The CO 2 adsorption capacity of the spray-coated carbon paper reaches 80% of its maximum value in only 4.37 ± 0.7 min. Moreover, its adsorption rate (114.6 mg/(g∙min) at 303 K) and desorption rate (239.9 mg/(g∙min) at 348 K) were 81.2% and 81.5% higher than those of the polyamine-impregnated carbon paper, respectively (12% CO 2 at atmospheric pressure). Their largest increases of 71% and 67% were achieved by adjusting the concentration of polyamine nanogel particles deposited on the carbon paper surface. The prepared material also presents stable recyclability over 10 wet adsorption–desorption cycles and the aging experiments. The results obtained in this study indicate that the synthesized materials can serve as promising energy-efficient solid adsorbents for CO 2 capture. [ABSTRACT FROM AUTHOR]

A study of plasma treatment of clay-coated paper is presented. The wettability of the paper surface before and after the plasma treatment was determined by measuring the water contact angle and surface free energy. The appearance of the surface-functional groups was determined by using high-resolution X-ray photoelectron spectroscopy, while changes in the surface morphology were monitored by scanning electron microscopy. Already after 0.25 s of the plasma treatment, the paper surface improved its wettability. The X-ray photoelectron spectroscopy analyses showed a gradual increase of oxygen-rich functional groups on the surface while scanning electron microscopy analyses did not show a significant modification of the morphology and no alternation of the surface structure after the plasma treatment. [ABSTRACT FROM AUTHOR]

In this study, four‐layer stacks of bleached, unrefined Kraft papers are exposed to a plane‐to‐plane dielectric barrier discharge at atmospheric pressure operated in a glow‐like discharge regime and sustained in a mixture of hexamethyldisiloxane and helium gases. Scanning electron microscopy confirms that the plasma‐deposited coating follows the roughness of the porous cellulosic substrate. Whereas fairly spatially homogeneous coatings are obtained on silicon, significant variations of the coatings' thickness, organic content, and water contact angle are observed along the gas flow lines on the Kraft paper. These effects are even more important in the presence of substrate outgassing. In addition, plasma‐generated species sequentially penetrate down to the fourth layer of the cellulosic substrate, rendering surfaces hydrophobic with very low water absorption kinetics. [ABSTRACT FROM AUTHOR]

The development of nontargeted analysis (NTA) methods to assess environmental contaminants of emerging concern, which are not commonly monitored, is paramount, especially when no previous knowledge on the identity of the pollution source is available. We compared complementary ionization techniques, namely electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), in the detection and identification of organic contaminants in tap and surface waters from South Florida. Furthermore, the performance of a simple rationalized NTA method was assessed by analyzing 10 complex mixtures as part of the US Environmental Protection Agency's Non-targeted Analysis Collaborative Trial interlaboratory study, where limitations of the NTA approach have been identified (e.g., number of employed databases, false positives). Different water bodies displayed unique chemical features that can be used as chemical fingerprints for source tracking and discrimination. The APCI technique detected at least threefold as many chemical features as ESI in environmental water samples, corroborating the fact that APCI is more energetic and can ionize certain classes of compounds that are traditionally difficult to ionize by liquid chromatography-mass spectrometry. Kendrick mass defect plots and Van Krevelen diagrams were applied to elucidate unique patterns and theoretical chemical space regions of anthropogenic organic compounds belonging to homologous series or similar classes covered by ESI and APCI. Overall, APCI and ESI were established as complementary, expanding the detected NTA chemical space which would otherwise be underestimated by a single ionization source operated in a single polarity setting. Environ Toxicol Chem 2022;41:1154-1164. © 2021 SETAC., (© 2021 SETAC.)

• Atmospheric pressure plasma modification of bleached, unrefined Kraft paper films • Both surface and volume treatment due the natural porous structure of the ligno-cellulosic materials • Low fragmentation of the organosilicon precursor in the non-thermal plasma • Formation of water-repellent igno-cellulosic materials with excellent dimensional stability even after water immersion In future years, recent progress in plasma processing using non-thermal plasmas at atmospheric pressure will be used to improve numerous natural by-product applications, including those based on materials derived from woody biomass. This work provides a detailed study of the morphological and chemical modification of bleached, unrefined Kraft paper obtained in homogeneous, plane-to-plane dielectric barrier discharges at atmospheric pressure in the presence of 2,4,6,8-tetramethylcyclotetrasiloxane (TMCTS) precursor. High-resolution SEM images highlight the presence of micro and nanoscale fibrous structures on the raw surface as well as their influence on the heterogeneous growth dynamics of the organosilicon film. Through FTIR and XPS analysis, it is further demonstrated that it is possible to take advantage of the natural porous structure of the cellulosic substrate to obtain both surface and volume treatment. Such analysis further revealed a low plasma-assisted fragmentation of the TMCTS precursor and a partial oxidation of the TMCTS precursor fragments during the plasma deposition process to form a Si-O-Si network. Over the range of experimental conditions investigated, wettability with water measurements reveal significant water repellency of the naturally hydrophilic cellulosic substrate. For sufficiently thick coatings, the plasma-processed materials remained unchanged even after 20 h of water immersion, a very promising result to reduce the degradation of ligno-cellulosic materials in humid and aggressive conditions. [ABSTRACT FROM AUTHOR]

Producing thick films of conducting polymers by a low‐cost manufacturing technique would enable new applications. However, removing huge solvent volume from diluted suspension or dispersion (1–3 wt%) in which conducting polymers are typically obtained is a true manufacturing challenge. In this work, a procedure is proposed to quickly remove water from the conducting polymer poly(3,4‐ethylenedioxythiophene:poly(4‐styrene sulfonate) (PEDOT:PSS) suspension. The PEDOT:PSS suspension is first flocculated with 1 m H2SO4 transforming PEDOT nanoparticles (≈50–500 nm) into soft microparticles. A filtration process inspired by pulp dewatering in a paper machine on a wire mesh with apertures dimension between 60 µm and 0.5 mm leads to thick free‐standing films (≈0.5 mm). Wire mesh clogging that hinders dewatering (known as dead‐end filtration) is overcome by adding to the flocculated PEDOT:PSS dispersion carbon fibers that aggregate and form efficient water channels. Moreover, this enables fast formation of thick layers under simple atmospheric pressure filtration, thus making the process truly scalable. Thick freestanding PEDOT films thus obtained are used as electrocatalysts for efficient reduction of oxygen to hydrogen peroxide, a promising green chemical and fuel. The inhomogeneity of the films does not affect their electrochemical function. [ABSTRACT FROM AUTHOR]

Deposition of transparent oxide films at atmosphere pressure onto polymeric substrates at room temperature is a technique gaining rapid acceptance. These films can be used for numerous applications such as antiscratch and water permeation barrier coatings. In this paper, a \sim 1.4 - \mu \text{m} SiOx layer has been deposited on polypropylene-coated paper at atmosphere pressure with a filamentary dielectric barrier discharge (DBD). The DBD linear discharge was driven by a 30-kHz power supply. Scanning electron microscope, X-ray photoelectron spectroscopy, and attenuated total reflection-Fourier transform infrared spectroscopy were used to characterize the deposited film. The deposited thin film decreased water permeation through the paper by \sim 15$ %. [ABSTRACT FROM PUBLISHER]

Siloxanes have been found widespread usages in our daily lives, but the knowledge on their migration, transformation and toxicity is still limited. Herein we explored the feasibility of using one-sided silica coated paper as filter membrane to capture siloxanes in the outdoor air, followed by direct mass spectrometric analysis. In contrast to mostly utilized fiber membrane, silica coated paper not only exhibited a higher selective sampling efficiency to three siloxanes with structures of H–[Si(CH 3) 2 –O] 7-9 -NH 2 from air, but also possessed a high tolerance to organic solvent during mass spectrometric analysis. Due to the above features, the analysis sensitivity of those siloxanes with silica coated paper has been improved 3.1–134.8 folds in contrast to those with commercial filter membrane. Furthermore, we monitored variation in the levels of those siloxanes for a period of one month, and found that a close association (R2 = 0.7924–0.9559) existed between their contents and climate parameters (e.g., temperature, weather, atmospheric pressure, humidity, wind direction and wind speed) as well as sampling volume. These knowledge provides a facile and effective methodology to both high-efficient sampling siloxanes and environmental assessment of siloxanes according to climate parameters. [Display omitted] • Develop a facile strategy for fabricating one-sided sorbent coated paper substrate. • Exploit silica coated paper for sampling and analyzing siloxanes in outdoor air. • Observe superior capacity of silica coated paper over conventional filter membrane. • Construct a relationship between siloxane contents in air and climate parameters. [ABSTRACT FROM AUTHOR]

Paper-based relics, which are an important part of cultural heritage worldwide, are at risk of imminent damage from various environmental sources. To protect them, the atmospheric pressure plasma polymerization of hexamethyldisiloxane (HMDSO) precursor has been explored on paper-based relics in situ. The macro and micro images taken during this process suggest that the in situ plasma treatment does not change the macro morphology and the micro structure of the treated paper-based relic samples. On the other hand, plasma treatment causes the polymerization of the HMDSO which then produces nanoparticles deposited onto the paper-based relics. These nanoparticles provide good waterproof properties with large static water contact angles and smaller rolling angles, which protect the paper-based relics from water penetration. Moreover, since the nanoparticles are deposited onto the fibers, waterproof fastness is ensured. Also, the examined mechanical properties of the treated and untreated paper-based relics indicate that the atmospheric pressure plasma treatment does not affect the strength of the paper very much. The results in this study show that atmospheric pressure plasma treatment with the use of HMDSO precursor is a good method to preserve paper-based relics. [ABSTRACT FROM AUTHOR]

Different amounts of a stable aqueous TiO2 hydrosol were used to fabricate paper sheets having photocatalytic activity. The TiO2 hydrosol was prepared in aqueous medium using titanium butoxide as precursor and acetic acid as catalyst for the hydrolysis of titanium butoxide. An aging process at room temperature and atmospheric pressure was finally applied to obtain crystalline anatase TiO2 hydrosol. The effects of different TiO2 hydrosol loadings on the mechanical strength and barrier properties of modified paper sheets were investigated in detail. The photocatalytic behavior of TiO2-modified paper sheets was investigated as well using methylene blue (MB) as target pollutant. [ABSTRACT FROM AUTHOR]

This study's aim is a comparison of the plasma-induced effects on polymers exposed in helium and argon gaseous environments in a pulsed dielectric barrier discharge at atmospheric pressure. Cellulose-based and synthetic polymers are tested with regard to a range of parameters, such as wettability, adhesion, surface energy and polarity, the oxygen amount in their structure, and surface morphology. The surface properties are analyzed by contact angle measurements, X-ray photoelectron spectroscopy, and scanning electron microscopy images. The results point to the efficient and remarkably stable modifications of the plasma-exposed surfaces, such as their enhanced adhesion, surface energy, and oxygen incorporation. Additionally, plasma provides significant oxygen uptake in cellulose-based materials that bear already prior to treatment a high amount of oxygen in their structure. The comparison between the properties of the non-permeable, homogeneous, smooth-surface synthetic polymer and those of the loosely packed, porous, heterogeneous cellulose-based polymers points to the different rates of plasma-induced modification, whereby a progressive alteration of cellulosic surface properties over much larger ranges of exposure durations is noted. Present experimental conditions ensure mild treatments on such sensitive material, such as paper, and this is without alterations of the surface morphology and the physical degradation of the material over a large range of treatment duration. [ABSTRACT FROM AUTHOR]

Background In recent years, mass spectrometry (MS) has been applied to clinical microbial biotyping, exploiting the speed of matrix-assisted laser desorption/ionization (MALDI) in recording microbe-specific MS profiles. More recently, liquid atmospheric pressure (AP) MALDI has been shown to produce extremely stable ion flux from homogenous samples and 'electrospray ionization (ESI)-like' multiply charged ions for larger biomolecules, whilst maintaining the benefits of traditional MALDI including high tolerance to contaminants, low analyte consumption and rapid analysis. These and other advantages of liquid AP-MALDI MS have been explored in this study to investigate its potential in microbial biotyping. Methods Genetically diverse bacterial strains were analyzed using liquid AP-MALDI MS, including clinically relevant species such as Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae. Bacterial cultures were subjected to a simple and fast extraction protocol using ethanol and formic acid. Extracts were spotted with a liquid support matrix (LSM) and analyzed using a Synapt G2-Si mass spectrometer with an in-house built AP-MALDI source. Results Each species produces a unique lipid profile in the m/z range of 400-1100, allowing species discrimination. Traditional (solid) MALDI MS produced spectra containing a high abundance of matrix-related clusters and an absence of lipid peaks. The MS profiles of the bacterial species tested form distinct clusters using principle component analysis (PCA) with a classification accuracy of 98.63% using a PCA-based prediction model. Conclusions Liquid AP-MALDI MS profiles can be sufficient to distinguish clinically relevant bacterial pathogens and other bacteria, based on their unique lipid profiles. The analysis of the lipid MS profiles is typically excluded from commercial instruments approved for clinical diagnostics.

Indium Gallium Zinc Oxide (IGZO) films are deposited using plasma‐enhanced spatial Atomic Layer Deposition (sALD) on substrates as large as 32 cm x 35 cm. Excellent uniformity and thickness control leads to high‐performing and stable co‐planar top‐gate self‐aligned (SA) thin‐film transistors (TFTs), demonstrating the viability of atmospheric spatial ALD as a novel deposition technique for the flat‐panel display industry. [ABSTRACT FROM AUTHOR]

For release-liner preparation, coating stabilization of the silicone layer on base paper often requires pre- and post-treatment. In this study, we used atmospheric pressure diffuse coplanar surface barrier discharge in roll-to-roll configuration. The results of prepared coating showed that the A4 size clay-coated paper sprayed with silicone oil (0.25–0.50 mL) gradually decreased the tape peeling force (180°) with prolonged and repeated air plasma post-treatment. Best results showing increased hydrophobicity and significantly enhanced release factor of the coating were obtained after the plasma treatment in a nitrogen atmosphere. The silicone coating on the clay-coated paper reduced the reference release force from 5.5 N/cm to less than 1.5 N/cm after the repeated silicone spraying and short nitrogen plasma post-treatment. The results of X-ray photoelectron spectroscopy and scanning electron microscopy indicate silicone curing by plasma post-treatment and pore-closing of base paper without changes of the bulk material. The aging test lasting 3 months revealed the stability of the prepared coating. [ABSTRACT FROM AUTHOR]

Generating a uniform non-equilibrium plasma in atmospheric pressure air has always been a challenge. It is believed that the maximum spacing for generating a uniform non-equilibrium plasma in atmospheric pressure air, whether using AC or nanosecond pulse drive, is 4 mm. Discharges are always non-uniform when the spacing is greater than 4 mm. In this paper, we propose a new type of dielectric barrier discharge structure to address this challenge. The left end of the structure rapidly increases the discharge spacing from 0.5 mm to 6 mm, while the right side of the main discharge gap maintains a uniform spacing of 6 mm. Nanosecond pulse voltage is used to drive the plasma, an ICCD camera is used to capture the image of the plasma during a discharge pulse cycle, which indicates that a uniform plasma within the 6 mm spacing of the main discharge gap is generated. Upon further reducing the ICCD camera's exposure time to 20 ns, it is revealed that the uniform plasma is formed due to the rapid propagation of the plasma from left to right at a speed of order of 105 m s−1. Due to the small transverse component of the external electric field, this rapid propagation behavior cannot be due to the external electric field. Therefore, this paper further proposes the hypothesis of electric dipole formation leading to this fast propagation. The hypothesis suggests that the charge separation on the surface of the anode forms an electric dipole, which generates a local discharge at its right end. This local discharge further triggers the discharge in the main gap, and the main gap discharge, in turn, forms a dipole due to charge separation again, by repeating this cycle, the plasma propagates rapidly to the right. Further analysis demonstrates that this dipole can indeed produce a strong electric field of up to 41 kV cm−1 at its right end, which is sufficient to induce a local discharge. Moreover, under such a strong electric field, the electron migration rate can indeed reach 105 m s−1. These findings support the plausibility of this hypothesis. [ABSTRACT FROM AUTHOR]

Detailed characterization and classification of precipitation is an important task in atmospheric research. Line scanning 2-D-video disdrometer technique is well established for rain observations. The two orthogonal views taken of each hydrometeor passing the sensitive area of the instrument qualify this technique especially for detailed characterization of non symmetric solid hydrometeors. However, in case of solid precipitation problems related to the matching algorithm have to be considered and the user must be aware of the limited spacial resolution when size and shape descriptors are analyzed. This work has the aim of clarifying the potential of 2-D-video disdrometer technique in deriving size, velocity and shape parameters from single recorded pictures. The need of implementing a matching algorithm suitable for mixed and solid phase precipitation is highlighted as an essential step in data evaluation. For this purpose simple reproducible experiments with solid steel spheres and irregularly shaped styrofoam particles are conducted. Self-consistency of shape parameter measurements is tested in 40 cases of real snow fall. As result it was found, that reliable size and shape characterization with a relative standard deviation of less than 5% is only possible for particles larger than 1 mm. For particles between 0.5 and 1.0mm the relative standard deviation can grow up to 22% for the volume, 17% for size parameters and 14% for shape descriptors. Testing the adapted matching algorithm with a reproducible experiment with styrofoam particles a mismatch probability of less than 2.5% was found. For shape parameter measurements in case of real solid phase precipitation the 2DVD shows self-consistent behavior. [ABSTRACT FROM AUTHOR]

This paper presents an experimental campaign conducted next to the Condoroma dam, in Perú, at 4075 m a.s.l. The tests carried out in this paper were conducted in a 21 m long channel located at the toe of Condoroma dam. The setup consisted of a series of standard profile spillways with a vertical upstream face of up to five different dimensionless heights (P/Hd) ranging from 0.5 to 2. The experimental results indicated that, the P/Hd ratio influences the discharge coefficients in Condoroma, and P/Hd ≥ 1 values are recommended for the design of the spillway profile. In addition, for all the P/Hd ratios studied, the discharge coefficients adjusted to the Condoroma altitude were lower than those reported by classical formulations used in conventional spillway designs. Finally, a generalized equation is proposed to estimate the discharge coefficient for standard spillways located in dams at similar elevations above sea level. [ABSTRACT FROM AUTHOR]

The external insulation strength of the power equipment sleeve in the substation and converter station will be reduced with the increase in altitude and atmosphere pollution. The weakness of external insulation seriously threatens the safe operation of electrical equipment. At present, there are few studies and conclusions that focus on the flashover characteristics of power equipment bushing in high-altitude polluted areas. Therefore, this paper takes the 220 kV voltage level bushing as the research object and studies the Alternating Current (AC) pollution flashover characteristics and lightning and switching impulse flashover characteristics at low pressure. The insulation configuration at high-altitude polluted areas is analyzed. Finally, the insulation configuration scheme, which is suitable for high-altitude polluted areas, is proposed. The results show that the AC pollution flashover voltages of the bushing decrease with the decrease in the atmospheric pressure and the increase in the salt density as a power exponent function. The impulse flashover voltages also decrease with the decrease in the atmospheric pressure as a power exponent function. The atmospheric pressure/pollution impact characteristic index is related to the type of voltage, the value of the atmospheric pressure, and the value of the salt density. The test bushing does not meet the insulation configuration requirements in some high-altitude polluted areas. Through the analysis and calculation of the test results, the bushing insulation configuration scheme in high-altitude polluted areas is proposed. The research results can provide a reference for the external insulation design of bushings in substations and converter stations in high-altitude polluted areas. [ABSTRACT FROM AUTHOR]

We have developed an innovative optical emission spectrometry imaging device integrating a diode laser for sample introduction and an atmospheric pressure plasma based on dielectric barrier discharge for atomization and excitation. By optimizing the device parameters and ensuring appropriate leaf moisture, we achieved effective imaging with a lateral resolution as low as 50 μm. This device allows for tracking the accumulation of Cd and related species such as K, Zn, and O 2 +∙ , in plant leaves exposed to different Cd levels and culture times. The results obtained are comparable to established in-lab imaging and quantitative methods. With its features of compact construction, minimal sample preparation, ease of operation, and low limit of detection (0.04 μg/g for Cd), this novel methodology shows promise as an in-situ elemental imaging tool for interdisciplinary applications., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The paper explores the possibility of implementing an advanced photogrammetric technique, generally employed for satellite measurements, on airglow imager, a ground-based remote sensing instrument primarily used for upper atmospheric studies, measurements of clouds for the extraction of cloud motion vectors (CMVs). The major steps involved in the algorithm remain the same, including image processing for better visualization of target elements and noise removal, identification of target cloud, setting a proper search window for target cloud tracking, estimation of cloud height, and employing 2-D cross-correlation to estimate the CMVs. Nevertheless, the implementation strategy at each step differs from that of satellite, mainly to suit airglow imager measurements. For instance, climatology of horizontal winds at the measured site has been used to fix the search window for target cloud tracking. The cloud height is estimated very accurately, as required by the algorithm, using simultaneous collocated Lidar measurements. High-resolution, both in space and time (4 min), cloud imageries are employed to minimize the errors in retrieved CMVs. The derived winds are evaluated against MST radar-derived winds by considering it as a reference. A very good correspondence is seen between these two wind measurements, both showing similar wind variation. The agreement is also found to be good in the both zonal and meridional wind velocities with RMSEs< 2.4 ms-1. At the end, the strengths and limitations of the algorithm are discussed, with possible solutions, wherever required. [ABSTRACT FROM AUTHOR]

Mercury‐free ultra‐violet light source, which were generated by high pressure plasma discharge sources in the atmospheric pressure region, have been proposed by using conventional dielectric barrier discharge. However, dielectric barrier discharge devices having conventional flat‐type electrodes as well as coaxial‐type electrodes, would be degraded by the avalanche and the deformation of electrode due to the secondary ion bombardment by high discharge‐starting voltages and abnormal discharges, under the conditions of ac voltages with typical peak‐to‐peak amplitudes of 1.5–6 kV. In this study, low dischargestarting voltage under high pressure can be expected by the enhancement of the local electric field concentration on cathode arrays having extremely uniform and sharp tips of Transfer Mold micro‐projection cathode arrays. These Transfer Mold microprojection cathode arrays have been fabricated by using Transfer Mold field emitter arrays (FEAs) fabrication method and evaluated for discharge characteristics as the first step for UV lighting applications. Transfer Mold micro‐projection cathode arrays can be useful for the extremely uniform plasma source applications having the low breakdown voltage, then expected to be applied to large area and flat‐type UV lighting applications to a great extent. [ABSTRACT FROM AUTHOR]

This paper presents the results of studies on the transformation of geraniol (GA) in the presence of the natural mineral bentonite. The paper determines the influence of temperature, catalyst content, and reaction time on the course of the process. In order to determine the most favorable process conditions, the catalytic tests were carried out without solvent and under atmospheric pressure. Three functions were chosen to determine the most favorable process conditions: GA conversion and the selectivities of the main products: linalool – LO and beta-pinene – BP. In addition, the paper optimize GA transformation process based on response surface methodology (RSM). The impact of the most relevant process indicators was presented. For all factors of the method, their effects on all primary parameters were determined in the form of second-degree polynomials, and such process conditions were determined to achieve their maximum. [ABSTRACT FROM AUTHOR]

This paper presents an analytical approach to envisage a suitable operating pressure and investigate the effect of squeezed-film damping on the transient response of a micromirror of size 200 µm × 200 µm and a deflection of 2.5 µm for space-based multiobject spectroscopy. While most MEMS devices are vacuum packaged to achieve a high Q and fast switching, the same may not be true for applications that are prone to vibrations and shocks. At small pressures, the micromirror can produce undesired deflections and oscillations, and hence, a high-pressure operation becomes necessary to alleviate these effects. The operating pressure and its effect on the transient response of the micromirror are investigated by solving linearized Reynold's equation and dynamic equation of motion using the numerical iteration method. The result shows an overdamped response above 10 kPa pressure. At 101 kPa, the micromirror exhibits a switching and release time of 102 µs and 95 µs, respectively. The analytical results are very close to the FEM results with a deviation of 8%. The result shows that operating a micromirror at atmospheric pressure serves the dual purpose of dispensing away with the requirement of vacuum packaging and providing immunity from vibrations and oscillation. [ABSTRACT FROM AUTHOR]

Increased effectiveness of methane drainage from sealed post-mining goaves in hard coal mines contributes to reduced methane emission from goaves into the mine ventilation system. This paper focuses on issues concerning the assessment of the additional amount of methane released from the goaf into mine workings during periods of atmospheric pressure drops, which can be captured with a methane drainage system. Thanks to the solutions presented in the paper, it is possible to control the efficiency of the goaf drainage system, which in turn leads to the reduction of methane emission from the mine ventilation air into Earth's atmosphere. These solutions are of great added value for both the environment and coal mines as they reduce the costs arising from greenhouse gas emissions that are incurred by mining companies, increasing the efficiency of methane capture and its use in gas engines or district heating systems. The paper uses relationships relating to the influence of atmospheric pressure changes on the process of gas release from the goaf according to the hysteresis loop of methane release during atmospheric pressure changes, which was developed based on conducted research. The analysis and conclusions presented in this paper may facilitate the development of strategies aimed at reducing methane emissions from a mine's ventilated air into Earth's atmosphere. [ABSTRACT FROM AUTHOR]

Atmospheric pressure cold plasma has the advantages of high reactive species content, free from the limitation of vacuum environment and low cost in polymer films pattern etching. However, due to the extension phenomenon of the jet, there are problems in the pattern etching, such as low processing accuracy and difficulty in process precise control. In this paper, an atmospheric pressure cold plasma jet diffusion limited etching model is established to simulate the etching process and surface etching morphology under different conditions, and a plasma jet processing platform is built for experimental confirmation. The effect of diffusion coefficient and move probability on the etching results is studied by numerical simulation. The experiment observes the extension phenomenon of the plasma jet hitting the glass slide under the influence of working voltage or nitrogen flow, and the color reaction of Starch-KI test paper. The results show that the simulated etching results are consistent with the extension phenomenon of the jet impinging on the glass slide. The greater the probability of the active particles moving downward, the greater the contact line width and the etching depth, which is the same as the experimental result of increasing the working voltage. The shielding gas can isolate the air, reduce the diffusion coefficient, and reduce the loss of particles, which is beneficial to plasma etching. It is hoped that the research results in this paper can provide a certain reference for realizing high-precision and controllable etching and process optimization of atmospheric pressure cold plasma jet. [ABSTRACT FROM AUTHOR]

Released in March 2023, GPT‐4 has shown remarkable proficiency in various scientific areas, including atmospheric pressure plasma research. The paper discusses how GPT‐4, supported by ScholarAI and Wolfram plugins, enhances research efficiency with its vast knowledge and inferencing skills. It focuses on plasma‐water‐based nitrogen fixation experiments, demonstrating GPT‐4's abilities in explanation, analysis, prediction, planning, and verification. The study also addresses challenges like interpreting non‐textual data and keeping pace with scientific advancements. It highlights GPT‐4's role in improving nitrogen fixation process efficiency, showcasing its utility in scientific analysis and decision‐making. The paper emphasizes the evolving role of AI in research and the need for the scientific community to adapt to the rise of more advanced AI systems. [ABSTRACT FROM AUTHOR]

The commonly used reference atmospheric profiles for the validation of retrieved atmospheric profiles for microwave sounders have bias compared with real atmospheric profile values, which is detrimental to the validation of the retrieval. Microwave sounder observations are the direct measurements of microwave radiation in atmospheric conditions and are a true representation of the status of the atmosphere. This paper proposed a validation method for the retrieved atmospheric temperature and atmospheric humidity profiles of the satellite-based microwave sounder using its own in-orbit observations. The validation experiments are performed both for the retrievals of the microwave temperature sounder-II (Xi'an Branch, China Academy of Space Technology, Xi'an, China. MWTS-II) and the microwave humidity and temperature sounder (National Space Science Center, Chinese Academy of Sciences, Beijing, China. MWHTS). The validation results show that the retrieved temperature profiles of MWTS-II have higher accuracy compared to the temperature profiles of ERA5 in the atmospheric pressure range of 3–30 hPa, and the accuracy of the rest of the pressure range is comparable between the profiles of ERA5 and the retrieved profiles. And the retrieved temperature profiles of MWHTS have higher accuracy compared to the temperature profiles of ERA5 in the atmospheric pressure level around 50 hPa and lower accuracy in the rest of the pressure levels. In addition, the retrieved humidity profiles of MWHTS have higher accuracy compared to the humidity profiles of ERA5 in the atmospheric pressure range of 350–925 hPa. The proposed validation method for the retrieved atmospheric temperature and atmospheric humidity profiles of MWHTS using its own observations is promising for improving the feasibility and reliability of the validation, and can be a good reference for the application of the satellite in-orbit observations and the optimization of the microwave sounders. [ABSTRACT FROM AUTHOR]

The construction of sub‐daily pressure series is described for the cities of London (GB) and Paris (FR). The series extend back 1692 and 1748, respectively, and as such they represent two of the longest sub‐daily series of barometric pressure available. These series are updated from the previously documented London and Paris daily series and offer more homogeneous series, and in the case of the London series a more temporally complete sequence of data. A pairwise homogenization procedure has been applied to the two series alongside the long series of pressure that exists for De Bilt (NL). The De Bilt series has been available for some time in the International Surface Pressure Dataset (ISPD), but further quality control and homogeneity‐checking procedures have been applied to the data in this paper and therefore the three series are released together in this dataset. The series are of immediate interest for understanding changes to storm activity across the English Channel and North Atlantic region over an extended timeframe but may also be assimilated into reanalysis datasets such as the 20th‐century reanalysis. [ABSTRACT FROM AUTHOR]

Atmospheric amines may play a crucial role in formation of new aerosol particles via nucleation with sulphuric acid. Recent studies have revealed that concentrations below 1 ppt can significantly promote nucleation of sulphuric acid particles. While sulphuric acid detection is relatively straightforward, no amine measurements to date have been able to reach the critical sub-ppt concentration range and atmospheric amine concentrations are in general poorly characterized. In this work we present a proof-of-concept of an instrument capable of detecting dimethyl amine (DMA) with concentrations even down to 8 ppq (parts per quadrillion, 0.008 ppt) for a 15 min integration time. Detection of ammonia and amines other than dimethyl amine is discussed. We also report results from the first ambient measurements performed in spring 2013 at a boreal forest site. While minute signals from some amines were observed, DMA concentration never exceeded the detection threshold of ambient measurements (20 ppq), suggesting that it is unlikely that nucleation at this location involves DMA. [ABSTRACT FROM AUTHOR]

Complex oceanic circulation and air--sea interaction make the eastern tropical Pacific Ocean (ETPO) a highly variable source of CO2 to the atmosphere. Although the scientific community have amassed 70 000 surface partial-pressure of carbon dioxide (pCO2) datapoints within the ETPO region over the past 25 years, the spatial and temporal resolution of this dataset is insufficient to fully quantify the seasonal to inter-annual variability of the region, a region where pCO2 has been observed to fluctuate by >300 µatm. Upwelling and rainfall events dominate the surface physical and chemical characteristics of the ETPO, with both yielding unique signatures in sea surface temperature and salinity. Thus, we explore the potential of using a statistical description of pCO2 within sea-surface salinity-temperature space. These SSS/SST relationships are based on in-situ SOCAT data collected within the ETPO. This statistical description is then applied to high resolution (0.25°) SMOS sea surface salinity and OSTIA sea surface temperature in order to compute regional pCO2. As a result, we are able to resolve pCO2 at sufficiently high resolution to elucidate the influence various physical processes have on the pCO2 of the surface ETPO. Normalised (to 2014) oceanic pCO2 between July 2010 and June 2014 within the entire ETPO was 41 µatm supersaturated with respect to 2014 atmospheric partial pressures. Values of pCO2 within the ETPO were found to be broadly split between southeast and a northwest regions. The north west, central and South Equatorial Current regions were supersaturated, with wintertime wind jet driven upwelling found to be the first order control on pCO2 values. This contrasts with the southeastern/Gulf of Panama region, where heavy rainfall combined with rapid stratification of the upper water-column act to dilute dissolved inorganic carbon, and yield pCO2 values under-saturated with respect to atmospheric partial pressures of CO2. [ABSTRACT FROM AUTHOR]

In remote sensing applications, such as differential optical absorption spectroscopy (DOAS), atmospheric scattering processes need to be considered. After inelastic scattering on N2 and O2 molecules, the scattered photons occur as additional intensity at a different wavelength, effectively leading to filling-in of both solar Fraunhofer lines and absorptions of atmospheric constituents. Measured spectra in passive DOAS applications are typically corrected for rotational Raman scattering (RRS), also called Ring effect, which represents the main contribution to inelastic scattering. In contrast to that, vibrational Raman scattering (VRS) of N2 and O2 has often been thought to be negligible, but also contributes. Consequences of VRS are red-shifted Fraunhofer structures in scattered light spectra and filling-in of Fraunhofer lines, additional to RRS. We describe how to calculate VRS correction spectra in analogy to the Ring spectrum. We discuss further the impact of VRS cross-sections for O2 and N2 on passive DOAS measurements. The relevance of VRS is shown for the first time in spectral evaluations of Multi-Axis DOAS data. This measurement data yields in agreement with calculated scattering cross-sections, that the observed VRS cross-section amounts to 2.2±0.4% of the cross-section of RRS under tropospheric conditions. It is concluded, that this phenomenon has to be included in the spectral evaluation of weak absorbers as it reduces the measurement error significantly and can cause apparent differential optical depth of up to 2.5 × 10-4. Its influence on the spectral retrieval of IO, Glyoxal, water vapour and NO2 in the blue wavelength range is evaluated. For measurements with a large Ring signal a significant and systematic bias of NO2 dSCDs up to (-3.8±0.4) × 1014 molec cm-2 at low elevation angles is observed if this effect is not considered. [ABSTRACT FROM AUTHOR]