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Since their introduction in the early decades of the 20th century, fluorescent pigments have found progressively wider applications in several fields. Their chemical composition has been optimized to obtain the best physical properties, but is not usually disclosed by the manufacturers. Even the other class of luminescent pigments, namely the phosphorescent ones, is now produced industrially. The peculiar optical properties of these pigments have attracted more and more the attention of famous artists since the middle of the last century. The Italian Black Light Art movement exploits the possibility of conveying different aesthetical messages depending on the kind of radiation (UV or visible) with which the artwork is illuminated. In the present work, a non-invasive in-situ investigation based on Raman, fluorescence, and visible-reflectance spectroscopies was performed on a series of Black Light Art paintings exhibited in Milan (Italy) in 2017, succeeding in the identification of the materials used by the artists. In particular, the use of both fluorescent and phosphorescent pigments, alone or combined with conventional synthetic organic pigments, has been recognized.

The legacy of the early days of the Atomic Age consists of many problematic sites worldwide, including radioactive waste dumps, uranium mines, spent fuel reprocessing plants, and defunct processing and enrichment plants. Although nature quickly reclaims abandoned sites, any remaining radioisotopes can pose a threat for millennia to come, long after the benefits gained from nuclear technology have faded. The field of nuclear industrial archaeology specialises in finding and characterising these sites to support local communities and site owners. Where maps and building plans have been lost, nuclear archaeologists deploy state-of-the-art analysis techniques on the ground to unravel the current state of legacy sites, and quantify the remaining radioactive inventories to the standard required by the nation the site is located within. The objectives of nuclear industrial archaeology are varied and site dependent. Whether the objective is to puzzle the forgotten history of activity back together or safeguard and recover dangerous radioactive materials, nuclear industrial archaeology adapts radioanalytical laboratory and site-surveying techniques in order to understand the site and allow scientists to communicate this information to support remediation efforts. This paper discusses current methodologies alongside a case study.

Mineralogy is the key to understanding the origin of Phobos and its position in the evolution of the Solar System. In situ Raman spectroscopy on Phobos is an important tool to achieve the scientific objectives of the Martian Moons eXploration (MMX) mission, and maximize the scientific merit of the sample return by characterizing the mineral composition and heterogeneity of the surface of Phobos. Conducting in situ Raman spectroscopy in the harsh environment of Phobos requires a very sensitive, compact, lightweight, and robust instrument that can be carried by the compact MMX rover. In this context, the Raman spectrometer for MMX (i.e., RAX) is currently under development via international collaboration between teams from Japan, Germany, and Spain. To demonstrate the capability of a compact Raman system such as RAX, we built an instrument that reproduces the optical performance of the flight model using commercial off-the-shelf parts. Using this performance model, we measured mineral samples relevant to Phobos and Mars, such as anhydrous silicates, carbonates, and hydrous minerals. Our measurements indicate that such minerals can be accurately identified using a RAX-like Raman spectrometer. We demonstrated a spectral resolution of approximately 10 cm−1, high enough to resolve the strongest olivine Raman bands at ~ 820 and ~ 850 cm−1, with highly sensitive Raman peak measurements (e.g., signal-to-noise ratios up to 100). These results strongly suggest that the RAX instrument will be capable of determining the minerals expected on the surface of Phobos, adding valuable information to address the question of the moon’s origin, heterogeneity, and circum-Mars material transport. Graphical Abstract

Strategic infrastructures made of pipelines transporting hydrocarbons across the world are exposed to the risk of failure due to damage accumulation during operation. The degradation process is promoted by material aging and enhanced by harsh service conditions. Severe consequences can be prevented by the long-life monitoring and integrity assessment of materials and components. Structural diagnosis can be assisted by non-destructive mechanical testing. This chapter provides an overview on the procedures at present available for pipeline steels in this context. The information content of hardness and instrumented indentation tests is specifically addressed. The focus is on the reliability of the predictions that can be provided by small sampling sizes when experimental information and numerical simulations are combined. The significance of such methodology for the evaluation of the current properties of exercised pipelines is illustrated together with the relevant validation studies. The gains resulting from the progressive technological advancements are also evidenced.

In recent years, the varnish caused by turbine oil oxidation products has become a serious problem in thermal power generation plants. In our laboratory, we have developed a varnish diagnosis method that uses membrane patch colorimetry for evaluating varnish potential. Membrane patch color is influenced by filtering conditions such as mixing solvent, oil temperature, and incubation period. It is important to understand the influence of these conditions on the patch color and oxidation products to properly evaluate oxidation products using membrane patch colorimetry. Hence, this study aims to investigate these conditions by using two experiments. First, we conducted a filtration test on sample oils that were filtered under different conditions, in which we altered the mixing solvent, oil temperature, and incubation period to investigate their influence on membrane patch color. Then, we investigated the behavior of oxidation products versus heating time, incubation period, and oil temperature using an in-situ analysis of a microscopic fourier transform infrared spectroscopy (FT-IR). In the filtration test, the membrane patch color became darker with increasing incubation period. Additionally, the results also indicated that the membrane patch color became brighter when the sample oil and solvent were mixed and/or the oil temperature was high. From the in-situ analysis using the microscopic FT-IR in the case of a heating process, the peak of 1710 cm-1, which is an absorption band of carboxylic acid (-COOH), shifted to a higher wave number. In the case of a holding process, the peak of 1710 cm-1 shifted to a lower wave number. Overall, the results suggest that the oxidation products became low-molecular owing to cleavage of hydrogen bond and easy solubility in turbine oil when the oil temperature was high, and that the oxidation products became high-molecular by hydrogen bonding and difficult to dissolve in turbine oil when the sample oil was cooled and stored. Moreover, from the behavior of the oxidation products at different temperatures in the in-situ analysis, the cleavage of hydrogen bond of oxidation products in turbine oil ended after reaching at least 60–70°C.

Accepted: 2018-01-19, 資料番号: SA1180311000

The complex reaction mechanism of iron-based Fischer-Tropsch synthesis comprises of manifold primary and secondary reaction pathways. Within this work, an experimental setup for spatially-resolved measurements on promoted iron-based Fischer-Tropsch catalysts is presented, allowing for a general study of the influence of operating conditions and promotion as well as of the influence of secondary reactions on product selectivity. It was found that, depending on catalyst composition, considerable hydrogenation of 1-alcohols and olefins occurs, while no influence of reinitiation of chain growth on product distribution could be found. © 2021 Published by Elsevier B.V. Bundesministerium für Wirtschaft und Klimaschutz (BMWi)

A hand-held diode laser is implemented for solid sampling in portable ambient mass spectrometry (MS). Specifically, a pseudocontinuous wave battery powered surgical laser diode is employed for portable laser diode thermal desorption (LDTD) at 940 nm and compared with nanosecond pulsed laser ablation at 2940 nm. Postionization is achieved in both cases using atmospheric pressure photoionization (APPI). The laser ablation atmospheric pressure photoionization (LAAPPI) and LDTD-APPI mass spectra of sage leaves (Salvia officinalis) using a field-deployable quadrupole ion trap MS display many similar ion peaks, as do the mass spectra of membrane grown biofilms of Pseudomonas aeruginosa: These results indicate that LDTD-APPI method should be useful for in-field sampling of plant and microbial communities, for example, by portable ambient MS. The feasibility of many portable MS applications is facilitated by the availability of relatively low cost, portable, battery-powered diode lasers. LDTD could also be coupled with plasma- or electrospray-based ionization for the analysis of a variety of solid-samples.

The Dual-Rasp sampling system has been developed for the unique sampling environment of a lander mission to the surface of Saturn's moon Enceladus. Plume material from the subsurface ocean that has fallen to the surface is desired resulting in an objective to sample the topmost layer of icy material. The low gravity and potential large range of surface properties are challenges for the sampling system. The Dual-Rasp sampling system has two counter-rotating rasp cutters with teeth that remove material that is thrown up between the cutters. Two prototypes of the Dual-Rasp sampling system were built and tested, one with a carousel and one that uses pneumatics for sample transfer.

In the current water monitoring panorama, certain benefits are expected to arise when themodus operandumof analysis shifts from sampling-based to purelyin-situapproaches. Since the appearance of the first submersible conductivity-temperature-depth (CTD) probe in the 80 s, clear efforts to move towards decentralized strategies have been reported in the literature, with some having even been brought to the stage of fruitful commercial- ization. Among the portfolio of available analytical techniques, only a handful of approaches offer clear potential for implementation in submersible devices, in terms of adequate analytical features, autonomy, feasibility of miniaturization, and ease of portability. Electrochemical sensors have demonstrated excellent characteristics for this purpose, particularly in the detection of ions. The present review analyses electrochemical sensors that have shown an aptitude forin-situmeasurements of ions, including trace metals, nutrients, and carbon species in seawater. The previous 5 years have been selected as the main period for review, although in some instances comment is made upon earlier contributions to the field or commercialized devices, where these are deemed to exemplify crucial technological advancements. There is a notable lack of electrochemical sensors being deployed inin-situapplications, and this scarcity is even more stark when seawater is considered: only a very few cases have been demonstrated under such challenging conditions. With the aim of providing inspiration towards genuine advances in the field ofin-situseawater analysis, this work also highlights some laboratory scale research as well as studies concerning other environmental waters than seawater.

Unlike more established subtractive or constant volume manufacturing technologies, additive manufacturing methods suffer from a lack of in-situ monitoring methodologies which can provide information relating to process performance and the formation of defects. In-process evaluation for additive manufacturing is becoming increasingly important in order to assure the integrity of parts produced in this way. This paper addresses the generic performance of inspection methods suitable for additive manufacturing. Key process and measurement parameters are explored and the impacts these have upon production rates are defined. Essential working parameters are highlighted, within which the spatial opportunity and temporal penalty for measurement allow for comparison of the suitability of different nondestructive evaluation techniques. A new method of benchmarking in-situ inspection instruments and characterising their suitability for additive manufacturing processes is presented to act as a design tool to accommodate end user requirements. Two inspection examples are presented: spatially resolved acoustic spectroscopy and optical coherence tomography for scanning selective laser melting and selective laser sintering parts, respectively. Observations made from the analyses presented show that the spatial capability arising from scanning parameters affects the temporal penalty and hence impact upon production rates. A case study, created from simulated data, has been used to outline the spatial performance of a generic nondestructive evaluation method and to show how a decrease in data capture resolution reduces the accuracy of measurement.

International audience; The thermal decomposition of uranyl peroxide tetrahydrate, (UO2)O2(H2O)2·2H2O, was studied by combining high temperature powder X-ray diffraction, scanning electron microscopy, thermal analyses and spectroscopic techniques (Raman, IR and 1H NMR). In situ analyses reveal that intermediates and final uranium oxides obtained upon heating are different from that obtained after cooling at room temperature and that the uranyl precursor used to synthesize (UO2)O2(H2O)2·2H2O, sulfate or nitrate, has a strong influence on the peroxide thermal behavior and morphology. The decomposition of (UO2)O2(H2O)2·2H2O ex sulfate is pseudomorphic and leads to needle-like shaped particles of metastudtite, (UO2)O2(H2O)2, and UO3-x(OH)2x·zH2O, an amorphous phase found in air in the following of (UO2)O2(H2O)2 dehydration. (UO2)O2(H2O)2·2H2O and the compounds resulting from its thermal decomposition are very reactive towards hydrofluorination as long as their needle-like morphology is kept.

A potential future in-situ lander mission to the surface of Enceladus could be the lowest cost mission to determine if life exists beyond Earth since material from the subsurface ocean, where the presence of hydrothermal activity has been strongly suggested by the Cassini mission, is available on its surface after being ejected by plumes and then settling on the surface. In addition, the low radiation environment of Enceladus would not significantly alter the chemical makeup of samples recently deposited on the surface. A study was conducted to explore various sampling devices that could be used by an in-situ lander mission to provide 1cc to 5cc volume samples to instruments. In addition to temperature and vacuum environmental conditions, the low surface gravity of Enceladus (1% of Earth gravity)represents a new challenge for surface sampling that is not met by sampling systems developed for microgravity (e.g., comets and asteroids)or higher gravity (e.g., Europa 13%g, Moon 16%g, or Mars 38%g)environments. It is desired to acquire surface plume material that has accumulated in the top 1cm to ensure acquisition of the least processed material. Several sampling devices were developed or adapted and then tested in simulated conditions that resemble the Enceladus surface properties. These devices and test results are presented in this paper.

The scope of white light excitation fluorescence in analyzing multifluorophoric systems has been explored. White light excitation fluorescence (WLEF) spectra retain the resultant fluorescence signature of all the fluorophores and their interactions although, in contrast to excitation-emission-matrix fluorescence (EEMF) spectra, resolution along the excitation axis is lost. The demonstration of the advantages of WLEF with regard to fiber optic compatibility, sensitivity, selectivity and simultaneous detection of multiple fluorophores suggests that WLEF based analytical techniques can be methods of choice in certain cases, especially with regard to low cost in situ analysis of an analyte. The analysis of multifluorophoric systems by WLEF using a fiber optic fluorimeter clearly shows the effectiveness of WLEF (i) in two-fluorophoric systems at low fluorophore concentrations in which the spectral additivity is retained and (ii) in a complex multifluorophoric system like diesel-kerosene mixtures. � 2011 The Royal Society of Chemistry.

Mobile instrumentation is of growing importance to archaeometry research. Equipment is utilized in the field or at museums, thus avoiding transportation or risk of damage to valuable artifacts. Many spectroscopic techniques are nondestructive and micro-destructive in nature, which preserves the cultural heritage objects themselves. This review includes over 160 references pertaining to the use of mobile spectroscopy for archaeometry. Following a discussion of terminology related to mobile instrumental methods, results of a literature survey on their applications for cultural heritage objects is presented. Sections devoted to specific techniques are then provided: Raman spectroscopy, X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy, laser-induced breakdown spectroscopy, and less frequently used techniques. The review closes with a discussion of combined instrumental approaches.

In this paper, a novel technique for fabricating Transmission Electron Microscopy (TEM) chips for investigating structural and piezoelectric properties of Pulse Laser Deposited (PLD) Lead Zirconium Titanate (PZT) thin films is presented. The method involves silicon-on-insulator (SOI) wafer technology together with deep reactive ion etching (DRIE) and highly selective etchants. This study is unique in the sense that it will facilitate in-situ characterization of the PLD PZT membranes during actuation. As well as PLD PZT, the proposed method can be applied to a variety of materials by proper selection of the etchants and tuning of the process parameters. Being a critical step of the process sequence, the deposition profile of the PZT layer on the Lanthanum Nickel Oxide (LNO) seed layer is characterized prior to fabrication. The results reveal that the PLD process is not conformal and the thickness of the LNO/PZT layer is different on surfaces with different topographies.

In this paper, a novel technique for fabricating Transmission Electron Microscopy (TEM) chips for investigating structural and piezoelectric properties of Pulse Laser Deposited (PLD) Lead Zirconium Titanate (PZT) thin films is presented. The method involves silicon-on-insulator (SOI) wafer technology together with deep reactive ion etching (DRIE) and highly selective etchants. This study is unique in the sense that it will facilitate in-situ characterization of the PLD PZT membranes during actuation. As well as PLD PZT, the proposed method can be applied to a variety of materials by proper selection of the etchants and tuning of the process parameters. Being a critical step of the process sequence, the deposition profile of the PZT layer on the Lanthanum Nickel Oxide (LNO) seed layer is characterized prior to fabrication. The results reveal that the PLD process is not conformal and the thickness of the LNO/PZT layer is different on surfaces with different topographies.

Proper recognition and repair of DNA damage is critical for the cell to protect its genomic integrity. Laser microirradiation ranging in wavelength from ultraviolet A (UVA) to near-infrared (NIR) can be used to induce damage in a defined region in the cell nucleus, representing an innovative technology to effectively analyze the in vivo DNA double-strand break (DSB) damage recognition process in mammalian cells. However, the damage-inducing characteristics of the different laser systems have not been fully investigated. Here we compare the nanosecond nitrogen 337 nm UVA laser with and without bromodeoxyuridine (BrdU), the nanosecond and picosecond 532 nm green second-harmonic Nd:YAG, and the femtosecond NIR 800 nm Ti:sapphire laser with regard to the type(s) of damage and corresponding cellular responses. Crosslinking damage (without significant nucleotide excision repair factor recruitment) and single-strand breaks (with corresponding repair factor recruitment) were common among all three wavelengths. Interestingly, UVA without BrdU uniquely produced base damage and aberrant DSB responses. Furthermore, the total energy required for the threshold H2AX phosphorylation induction was found to vary between the individual laser systems. The results indicate the involvement of different damage mechanisms dictated by wavelength and pulse duration. The advantages and disadvantages of each system are discussed.

The target of the in-situ research of optical activity in extraterrestrial samples stimulated an extended investigation of a GC–MS method based on the derivatization of amino acids by using a mixture of perfluorinated alcohols and perfluorinated anhydrides. Amino acids are converted to their N(O,S)–perfluoroacyl perfluoroalkyl esters in a single-step procedure, using different combinations of the derivatization reagents trifluoroacetic anhydride (TFAA)-2,2,2-trifluoro-1-ethanol (TFE), TFAA-2,2,3,3,4,4,4-heptafluoro-1-butanol (HFB), and heptafluorobutyric anhydride (HFBA)-HFB. The derivatives obtained are analyzed using two different chiral columns: Chirasil-L-Val and γ-cyclodextrin (Rt-γ-DEXsa) stationary phases which show different and complementary enantiomeric selectivity. The mass spectra of the derivatives are studied, and mass fragmentation patterns are proposed: significant fragment ions can be identified to detect amino acid derivatives. The obtained results are compared in terms of the enantiomeric separation achieved and mass spectrometric response. Linearity studies and the measurement of the limit of detection (LOD) show that the proposed method is suitable for a quantitative determination of enantiomers of several amino acids. The use of the programmed temperature vaporiser (PTV) technique for the injection of the untreated reaction mixture is a promising method for avoiding manual treatment of the sample and decreasing the LOD. Chirality, 2006. © 2006 Wiley-Liss, Inc.