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A high-standard pore water sampling in deep-sea sediments is essential for scientific and technical studies such as determining geochemical anomalies on the seafloor. This paper designed a multi-depth in-situ pore water pressure-retaining sampler (MIPPS). It can sample deep-sea in situ pore water with multiple depths, high resolution, and low disturbance. We evaluated the indicators and functions of the sampler through simulation calculations, laboratory, offshore and deep-sea experiments. The diffusion between pore water and deionized water was determined using Ansys Fluent simulation to select a suitable tube to reduce contamination. The pressure test shows that the sampler has a pressure-retaining capacity of 30 MPa. The experiments show the laboratory sampling rate in sediment at different temperatures. Furthermore, in the offshore experiment, we analyze the reasons for the decrease in the offshore sampling rate. Finally, the sampler was carried on board the heavy-duty ROV-Jellyfish for a deep-sea experiment in the South China Sea. The deep-sea experiment's success indicates that the MIPPS is accurate and trustworthy in practice. Then the sampler continued to be used for the sea area of methane seepage for in-depth scientific applications. [ABSTRACT FROM AUTHOR]

Ultrasound (US) releases polycyclic aromatic hydrocarbons (PAHs) from contaminated creosote sediments and degrades PAHs in aqueous solution. However, it is unclear how much PAHs release occurs during active US compared to after US is stopped. In this study, solid-phase microextraction (SPME) was used to determine aqueous PAH concentrations desorbed from Little Scioto River creosote contaminated sediment during exposure to 20 kHz ultrasound (US) at a power of 430 W L−1. First, SPME fiber-water partition coefficients,KSPME, were experimentally determined and shown to be comparable with previous studies. Next, PAH concentrations released into aqueous solution were determined by sequentially exposing fresh, conditioned SPME fibers in a reactor containing the contaminated sediment and DI for 10 min periods. Three consecutive 10 min periods each were measured during US and after US. Compared to mixing only, PAHs desorbed during ultrasound was significantly higher. In addition, for phenanthrene, anthracene, and fluoranthene, US showed significantly higher aqueous concentrations during US compared with after US. For these less soluble PAHs, desorption into the aqueous phase reaches and surpasses expected equilibrium aqueous concentrations. However, when US is ceased, PAHs appear to resorb onto sediment resulting in the lower concentrations measured in these PAH compounds after US that are similar to expected equilibrium aqueous concentrations. Typical analytical extraction methods for determining the effects of US require stopping treatment and may underestimate the potential US has for release of contaminants from sediment during US. Using SPME during US treatment reveals that the concentration of PAHs during US may surpass the expected equilibrium aqueous concentration of some PAHs congeners. To our knowledge, this higher concentration observed during US compared to after US has not been shown previously.

• Diagnostic of ancient paper by completely non-invasive diagnostic approach. • UV–Vis-NIR imaging, FORS and fluorescence spectroscopies performed in-situ. • HPLC and FTIR analyses on extracts obtained by a smart sampling method. • A complete characterization of two letters of St. Francis de Sales (1567–1622) was obtained. We report a non-invasive and multi-analytical physico-chemical method for the characterization of paper artworks, able to identify sizing, inks, and glues and to quantify oxidative degradation by-products. The proposed methodology is mostly carried out in situ by using easy-to-use and cheap portable instrumentation for the acquisition of multispectral images, punctual ultraviolet-visible-near infrared fiber-optics reflectance spectroscopy (FORS) and punctual fiber optics fluorescence spectroscopy. Further analytical information is provided by non-invasive in-situ sampling of paper surface by using soft latex sponges, making possible laboratory chromatographic and infrared spectroscopic analyses on the aqueous sponge extracts. The proposed diagnostics method was applied to two 17th century letters written by St Francis of Sales (1567–1622), collected at the Chigi Palace in the town of Ariccia (Italy). Results show an intense oxidative degradation of the letters, also localized in water spots, and the presence of carboxylic acids by-products. Analysis of FORS spectra provided the concentration of chromophores in the paper substrate. The diagnostic method allowed the identification of gelatin sizing, the presence of starch glue in specific areas of the letters and the type of ink used in the text. Our diagnostic approach aims to offer to conservator-restorer a characterization of a paper artwork, that can be applied to other, for a correct planning of conservation interventions. [ABSTRACT FROM AUTHOR]

Supercritical geothermal resource is a renewable and carbon-free energy with enormous potential. Quantitative assessment of the geochemical processes involved in the future operation of this resource requires a comprehensive understanding of quartz solubility in subcritical and supercritical water. However, quartz solubility behaviors from subcritical to supercritical conditions are unclear, and the quartz solubility model requires refinement by improving the accuracy of experimental measurements. In this study, a series of in-situ sampling and measurements are conducted to investigate quartz solubility at 300–500 °C and 25–50 MPa by exploiting a novel and specifically designed experimental apparatus. The results indicate that the use of in-situ sampling and resistance continuous monitoring procedures can bring an accurate and reliable estimation of quartz solubilities near the supercritical point and in the low-density region. It also emerged that the quartz solubility in water is significantly affected by temperature and pressure both under subcritical and supercritical conditions, showing a positive correlation with pressure at isothermal and a retrograde behavior near the supercritical point. These features are interpreted by the thermodynamic theory, quartz hydrolysis process, and mathematical model. By combining our experimental results with high-quality data from the literature, a five-parameter density model is provided for the calculation of the silica concentrations in aqueous fluids up to supercritical geothermal conditions. To overcome the current limitations in the modeling of supercritical geothermal fluids, future experimental work needs to collect additional data on silica in real geofluids (e.g., saline fluid) to develop an advanced model. The findings of this study can help for a better understanding of geochemical processes in supercritical geothermal systems, as well as ore deposits and vent structures. • New experimental method enables accurate estimation of quartz solubility. • Density models are evaluated and refined according to the experimental results. • Quartz dissolution behaviors at supercritical geothermal conditions are interpreted. [ABSTRACT FROM AUTHOR]

The ICES (International Council for the Exploration of the Sea) Working Group on Oceanic Hydrography (WGOH) was established in the late 1970's with the aim of gathering experts in physical oceanography to provide regular science-based assessments of the North Atlantic hydrographical condition (basically termohaline fields). From the beginning, the WGOH has relied on repeated long-term in-situ sampling at key sites around the North Atlantic, the Nordic Seas and adjacent shelf seas. An annual Report on Ocean Climate (IROC), produced by the WGOH since the late 1990's, summarizes trends in regional hydrography and identifies patterns linking these changes across the North Atlantic. Regional analyses are prepared by local experts who are directly involved in the monitoring programs responsible for collecting data presented in the report. An interactive webpage created in 2013 allows users to browse and download data that inform the IROC. Within the last two decades the physical oceanography community has evolved quickly incorporating technological advances such as autonomous devices into classical in-situ sampling programs. The WGOH has embraced such technological developments without diverting focus from ongoing in-situ long-term monitoring programs. Having longstanding experience synthesizing data and expertise from a large number of operational programs spanning an extensive international footprint, the WGOH has a unique perspective to offer the global ocean observing community. Here we discuss how we might foster connections with ICES to benefit the GOOS (Global Ocean Observing System) community.

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]

Abstract This study assessed the effectiveness of dredging in controlling arsenic (As), selenium (Se), and antimony (Sb) contamination in sediments, by examining contaminant concentrations in sediments six years after dredging was completed. High-resolution diffusive gradients in thin films (DGT) and dialysis (HR-Peeper) techniques were used to monitor the concentrations of DGT-labile metalloids and soluble metalloids in sediments, respectively. Results revealed that dredging effectively remediated metalloid contamination in sediments only in April, July and/or January. Compared to non-dredged sediments, the concentrations of soluble and DGT-labile As, Se, and Sb in dredged sediments decreased on average by 42%, 52%, and 43% (soluble), and 54%, 50%, and 53% (DGT), respectively. The effectiveness of the dredging was primarily due to the transformation of metalloids from labile to inert fractions, which increased the ability of the sediments to retain the metalloids, and the slowed rate of resupplied metalloids from available solid pools. In contrast, negligible/negative effects of dredging were seen in October, and the concentrations of soluble and DGT-labile metalloids even increased in some profiles of dredged sediments. This was mainly caused by a release of the metalloids from algal degradation, which may offset the dredging effectiveness. Graphical abstract Image 1 Highlights • Dredging effects varied by season, reflected by metalloid concentrations. • Dredging was most effective in April, July and/or January. • Efficacy due to higher fraction of inert metalloids with slower kinetic response. • Dredging had negligible and negative effects in October. • Algal decomposition and metalloid release suppressed dredging efficacy. [ABSTRACT FROM AUTHOR]

[Display omitted] • CFD modeling is used to simulate a catalytic plate reactor with a movable capillary for the CO 2 methanation. • 3D reactive CFD model predictions show very good agreement with in-situ axial gas composition. • The capillary did not affect the catalytic behaviour and the quality of the kinetic data collected. A catalytic plate reactor with a small movable sampling capillary enables us to gather a significantly larger set of kinetic data for the parameter estimation than using a typical steady-state packed-bed reactor with end-of-pipe measurement. In this study, a reactive three-dimensional CFD model developed with catalyticFOAM is validated by experimental axial gas species concentration profiles and then used to investigate the flow dynamics and study the effect of the immersed capillary for various operating conditions for the CO 2 methanation reaction over Ni/Al 2 O 3 catalyst. The results confirmed that the presence of the capillary (diameter 0.5 mm, continuous vs. open-ended) inside the rectangular channel (5 × 40 × 100 mm), the position of the orifice (diameter 0.25 mm), and the suction (2 to 8 ml/min) did not affect the quality of the kinetic data collected. For the current design of the reactor inlet, the flow fully develops within the first 10–25 mm of the reactor domain depending on the total flow rate (100 to 300 ml N /min). Hence, up to 90% of the reactor's length can be used for in-situ measurements. This work demonstrates that our channel reactor is very suitable for collecting kinetic data, especially for fast and exothermic heterogeneous catalyzed reactions, with a high spatial resolution for gas composition and catalyst surface temperature. [ABSTRACT FROM AUTHOR]

The catalytic partial oxidation (CPOX) of several hydrocarbon mixtures, containing n-dodecane (DD), 1,2,4-trimethylbenzene (TMB), and benzothiophene (BT) as a sulfur compound was studied over a Rh/Al2 O3 honeycomb catalyst. The in-situ sampling technique SpaciPro was used in this study to investigate the complex reaction system which consisted of total and partial oxidation, steam reforming, and the water gas shift reaction. The mixtures of 83 vol % DD, 17 vol % TMB with and without addition of the sulfur compound BT, as well as the pure hydrocarbons were studied at a molar C/O-ratio of 0.75. The spatially resolved concentration and temperature profiles inside a central channel of the catalyst revealed three reaction zones: an oxidation zone, an oxy-reforming zone, and a reforming zone. Hydrogen formation starts in the oxy-reforming zone, not directly at the catalyst inlet, contrary to methane CPOX on Rh. In the reforming zone, in which steam reforming is the predominant reaction, even small amounts of sulfur (10 mg S in 1 kg fuel) block active sites. [ABSTRACT FROM AUTHOR]

This research presents a novel integrated methodology for the experimental characterization of historical mortars, including different types of laboratory tests. Different experimental tests on lime mortar brickwork were carried out, including Brazilian tests on core drilled masonry samples with one diametral mortar joint and double punch tests on extracted mortar joints. By representing the mortar’s state of failure on the Mohr’s plane for the different tests, it is possible to estimate the material’s strength envelope through a least square minimization method. The proposed approach can be useful to evaluate the compressive, tensile and shear behaviour of mortar in existing structures. [ABSTRACT FROM AUTHOR]

The catalytic partial oxidation (CPOX) of several hydrocarbon mixtures, containing n-dodecane (DD), 1,2,4-trimethylbenzene (TMB), and benzothiophene (BT) as a sulfur compound was studied over a Rh/Al2O3 honeycomb catalyst. The in-situ sampling technique SpaciPro was used in this study to investigate the complex reaction system which consisted of total and partial oxidation, steam reforming, and the water gas shift reaction. The mixtures of 83 vol % DD, 17 vol % TMB with and without addition of the sulfur compound BT, as well as the pure hydrocarbons were studied at a molar C/O-ratio of 0.75. The spatially resolved concentration and temperature profiles inside a central channel of the catalyst revealed three reaction zones: an oxidation zone, an oxy-reforming zone, and a reforming zone. Hydrogen formation starts in the oxy-reforming zone, not directly at the catalyst inlet, contrary to methane CPOX on Rh. In the reforming zone, in which steam reforming is the predominant reaction, even small amounts of sulfur (10 mg S in 1 kg fuel) block active sites.

An improved apparatus based on the static-analytic method for reliable vapor–liquid equilibrium (VLE) data measurement is presented in this work. It has been applied to investigate systems containing organic sulfur compounds. New sampling mechanisms were combined with ROLSI™ capillary samplers to achieve on-line sampling for both vapor and liquid phases in a pressure range between 0.1 and 10 bar. Phase samples were directly sent to a gas chromatograph for composition analysis. The equipment was tested against other commonly used experimental methods in this pressure range on the ( n -butane + ethanol) and (diethyl sulfide + ethanol) systems. The obtained data were correlated by Wilson model and compared with existing data. The improved apparatus has shown comparable performances to existing methods, while showing some advantages such as complete PTxy phase measurements and less product consumption. After the validation step, additional VLE data for binary systems of interest, (diethyl sulfide + n -butane) and (1-pentanethiol + 1-pentanol), were reported and modeled in this work. [ABSTRACT FROM AUTHOR]

• [PAHs] aq during US is higher than [PAHs] aq after US is ceased. • Analysis of [PAHs] after US treatment is ceased underestimates released PAHs. • [PAHs] resorb onto sediment within 10 min after US is turned off. • SPME fibers allow for measurement of [PAHs] aq during course of US treatment. Ultrasound (US) releases polycyclic aromatic hydrocarbons (PAHs) from contaminated creosote sediments and degrades PAHs in aqueous solution. However, it is unclear how much PAHs release occurs during active US compared to after US is stopped. In this study, solid-phase microextraction (SPME) was used to determine aqueous PAH concentrations desorbed from Little Scioto River creosote contaminated sediment during exposure to 20 kHz ultrasound (US) at a power of 430 W L−1. First, SPME fiber-water partition coefficients, K SPME , were experimentally determined and shown to be comparable with previous studies. Next, PAH concentrations released into aqueous solution were determined by sequentially exposing fresh, conditioned SPME fibers in a reactor containing the contaminated sediment and DI for 10 min periods. Three consecutive 10 min periods each were measured during US and after US. Compared to mixing only, PAHs desorbed during ultrasound was significantly higher. In addition, for phenanthrene, anthracene, and fluoranthene, US showed significantly higher aqueous concentrations during US compared with after US. For these less soluble PAHs, desorption into the aqueous phase reaches and surpasses expected equilibrium aqueous concentrations. However, when US is ceased, PAHs appear to resorb onto sediment resulting in the lower concentrations measured in these PAH compounds after US that are similar to expected equilibrium aqueous concentrations. Typical analytical extraction methods for determining the effects of US require stopping treatment and may underestimate the potential US has for release of contaminants from sediment during US. Using SPME during US treatment reveals that the concentration of PAHs during US may surpass the expected equilibrium aqueous concentration of some PAHs congeners. To our knowledge, this higher concentration observed during US compared to after US has not been shown previously. [ABSTRACT FROM AUTHOR]

The catalytic partial oxidation (CPOX) of methane is studied over staged palladium/alumina and rhodium/alumina coated monoliths by an in-situ sampling technique to resolve the axial species concentration and temperature profiles. A molar C/O ratio of unity, which is stoichiometric for the formation of synthesis gas (CO/H 2 ), and short residence times are chosen for this autothermal process. The profiles of the staged monoliths are compared with profiles of single-sliced palladium/alumina and rhodium/alumina coated monoliths. The investigations clearly show two zones inside the catalytic channel. In the staged catalyst with the Pd stage being on the upstream side as well as in the single-sliced Pd catalyst, hydrogen is not formed before oxygen is almost completely consumed, i.e. a total oxidation zone is observed in front of a steam reforming zone. In the Rh catalyst, in the first 2 mm zone, total oxidation and steam reforming occur as prevalent reactions followed by a reforming zone with steam reforming as dominating reaction. The observations are interpreted in terms of the indirect and direct route towards hydrogen formation in CPOX of methane. [ABSTRACT FROM AUTHOR]

• Compression tests on brick masonry cylinders of 150 mm and 90 mm are presented. • Results from laboratory controlled and real historical materials are compared. • The average ratio between the compressive strengths of 150 mm and 90 mm cores is 0.75. • The average ratio between the Young's moduli of 150 mm and 90 mm cores is 0.85. • Testing 90 mm cylinders is found to be an alternative for inspecting existing masonry. This paper presents the results of an experimental programme about the evaluation of the size effect on the compressive behaviour of cylindrical samples of existing masonry. The study focuses on the in-situ coring and experimental testing of core specimens with 150 mm and 90 mm diameter. The 150 mm cylinder, recurrent in minor destructive evaluation of the compressive strength of existing masonry, includes four brick pieces, two mortar beds and one head joint. The 90 mm specimen includes one mortar bed and two segments of brick, and inflicts less damage on the inspected structural member due to its lower invasivity. The experimental research investigates the size effect on four different types of clay brick masonry. The first type was built in the laboratory using historical-like materials. The other three types of masonry belong to structural walls of existing historical buildings. The combination of experimental results from laboratory controlled materials and existing historical members shows that the size of the cylindrical specimen has regular effect on the compressive strength and the Young's modulus. The consistent relationship found between the compressive strengths of the 150 mm and 90 mm core samples allows the use of the latter specimen for a more respectful inspection of existing structural masonry. [ABSTRACT FROM AUTHOR]