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Improved methods to assess the degradation of coil coatings to approximate lifetime have been an area of academic and industrial interest for decades. This work aims to elucidate the differences in the degradation behavior of two coil coating systems: one standard commercial formulation and one formulation with a significant addition of biorenewable reactive diluents. Depth-resolved degradation behavior of samples exposed to accelerated and natural field weathering is assessed. Focal plane array attenuated total reflection-Fourier transform infrared spectroscopy was used to acquire high-resolution chemical data from a sloping cross section. The results agreed with conventional photoacoustic spectroscopy. Degradation profiles for the two coatings were significantly different, with the biobased samples showing a more durable behavior. This study provides a method for detailed assessment of coating degradation, giving a good estimation of its durability. This is both a way to compare the performance of coating systems and to improve the understanding of the impact of exposure conditions, paving the way for the development of more sustainable coil coatings., QC 20230421

X-rays are routinely used for structural studies through scattering, and femtosecond X-ray lasers can probe ultrafast dynamics. We aim to capture the femtosecond dynamics of liquid samples using simulations and deconstruct the interplay of ionization and atomic motion within the X-ray laser pulse. This deconstruction is resolution dependent, as ionization influences the low momentum transfers through changes in scattering form factors, while atomic motion has a greater effect at high momentum transfers through loss of coherence. Our methodology uses a combination of classical molecular dynamics and plasma simulation on a protic ionic liquid to quantify the contributions to the scattering signal and how these evolve with time during the X-ray laser pulse. Our method is relevant for studies of organic liquids, biomolecules in solution or any low-Z materials at liquid densities that quickly turn into a plasma while probed with X-rays.

In this study, the local electrochemical activity of untreated and passivated (natural or chemical passivation) zinc specimens was observed during immersion in a 0.1-M NaCl solution. The localized anodic activity during the exposure, measured with the scanning vibrating electrode technique, was linked to zinc dissolution by the pitting corrosion mechanism. It was correlated to specific corrosion products characterized by Fourier transmission infrared (FTIR) microscopy. FTIR molecule maps were produced from individual pitting corrosion sites (100-200 mu m in width). With argon ion beam milling and latest energy-dispersive X-ray spectroscopy (EDS) technology, element maps with a high spatial resolution (MUCH LESS-THAN100 nm) were recorded from abrasion- and beam-sensitive corrosion products, showing a residual layer structure. This study demonstrates the capability of FTIR mapping, cross-section polishing, and state-of-the-art scanning electron microscopy imaging, and EDS element mapping to produce high-resolution elemental, molecular, and visual information about pitting corrosion mechanisms on a hot-dip galvanized steel sample., QC 20210901

Introduction Night-time polyuria as the dominating pathophysiological mechanism for primary monosymptomatic nocturnal enuresis (PMNE) has been put in question with nocturnal detrusor overactivity and high arousal thresholds as alternatives. An earlier finding of night-time polyuria in 12% of healthy non-enuretic schoolchildren underscores that excessive night-time diuresis per se is unlikely the major cause of PMNE. Objective The objective of this study was to compare the night-time diuresis pattern in children with and without PMNE and to evaluate the role of night-time polyuria in provoking enuretic episodes in children with PMNE. Study design Night-time diuresis pattern was recorded in 27 children with PMNE, aged 6–15 years, and 29 non-enuretic children, aged 6–13 years. Using a portable ultrasound recorder, the bladder volume was estimated at 15-min intervals for at least three nights with the child sleeping in its own bed at home. The volume of enuretic episodes was controlled using preweighed diapers. All voids were registered by time and volume. Diuresis during night time was estimated from the slope of regression lines fitted to ultrasound recording points. Mean night-time diuresis was calculated from total urine production during the night and time interval from the last void before bedtime to the first morning void. Results Night-time bladder filling pattern was recorded from 189 nights, giving 149 interpretable patterns for analysis (77 children with PMNE and 72 dry children). The night-time diuresis pattern was similar for children with or without PMNE, showing large variability between different nights of the same child. Most nights displayed a smooth bladder filling at constant low rate, whereas other nights showed an early phase with high diuresis followed by a longer period of low diuresis with no difference between the two groups. Discussion Night-time diuresis has been non-invasively monitored in children while asleep in their own beds at home. The, Funding Agencies|County of Ostergotland; Swedish Medical Research Council, Sweden; Ferring Lakemedel AB, Malmo, Sweden

The main aim of the present study has been to investigate the electrochemical behavior of, and oxide film formation on, the bulk amorphous Zr55Cu30Ni5Al10 alloy and the crystalline counterpart in simulated body fluid. Different analytical methods, e.g., polarization and electrochemical impedance measurements, were used to compare the results of the samples when exposed to, phosphate buffered saline (PBS), with or without the addition of protein (albumin). Moreover, the influence of pH on the corrosion behavior of the materials was also investigated. Pitting corrosion was observed to exist on both amorphous and crystalline samples after exposure to the PBS solution, but the passivity region was much smaller for the crystalline material. The addition of protein to the PBS solution improved passive behavior and led to higher pitting potential in the case of the crystalline samples, while the pitting corrosion potential decreased slightly in the case of the amorphous samples. Furthermore, a decrease in the pH level accelerates the dissolution rate of both materials when exposed to the PBS environment, however, in the presence of albumin the pitting corrosion potential increased in the case of both materials., QC 20160817

Zn-5Al and Zn-3Al-2Mg model alloys were cast and heat treated in order to obtain specimens with distinct microstructures and identical chemical compositions. The microstructure was characterised in detail to identify composition, size and distribution of present phases. Mass losses of samples with different microstructures and identical chemical compositions that were subjected to a cyclic corrosion test and a test under non-rinsing conditions differed by a factor of up to two. The mechanism is discussed based on measurements of corrosion stability of individual phases and chemical and phase compositions of corrosion products., QC 20210901

QC 20220510

Trace elements are unevenly distributed and speciated throughout the cereal grain. The germ and the outer layers of the grain have the highest concentrations of trace elements. A large fraction of the trace elements is therefore lost during the milling process. The bioavailability of the remaining trace elements is very low. This is usually ascribed to the formation of poorly soluble complexes with the phosphorus storage compound phytic acid. Hence, analysis of the total concentration of trace elements in grain tissues must be combined with a speciation analysis in order to assess their contribution to human nutrition. This chapter deals with the fractionation of anatomically very different cereal tissues. Procedures for microscaling of digestion procedures are outlined together with requirements for the use of certified reference materials in elemental profiling of grain tissue fractions. Methods for extraction and analysis of complexes containing trace elements in the grain tissue fractions are described. Finally, the chapter concludes with criteria for choice of chromatographic methods and setting of ICP-MS instrument parameters.

The initial atmospheric corrosion of zinc induced by formic acid, acetic acid, and propionic acid has been followed in situ with infrared reflection absorption spectroscopy (IRAS). An optical model was applied to quantify the IRAS data, which enabled the absolute amounts of the two main species detected, ZnO and zinc carboxylate (mainly hydrated or hydroxyl zinc carboxylate), to be derived. The formation rate of zinc carboxylate increases as propionic < acetic < formic acid and is mainly governed by the deposition velocity of each acid into the existing aqueous adlayer. The formation rate of ZnO and the overall corrosion rate of zinc increase in the order formic < acetic < propionic acid and are mainly attributed to the expected pH of the aqueous adlayer. The corrosion rates deduced are at least 1 order of magnitude higher than the experimentally determined field data due to a higher organic acid concentration used herein (120 ppb) and a higher average relative humidity (90%)., QC 20100525

A multianalytical approach with in situ capability has been used to explore the initial oxidation of zinc in all with 90% relative humidity at 20 degrees C. The only surface species identified were zinc oxide (ZnO) and reversibly adsorbed water. Atomic force microscopy and X-ray diffraction revealed the homogeneous nucleation of ZnO grains the kinetics of ZnO Formation as followed quantitatively by in situ IR reflection-absorption spectroscopy (IRAS) integrated with a quartz crystal microbalance up to an average film thickness of 50 nm after 72 It of exposure. The quantitative results exhibit good agreement with ex situ cathodic reduction and with optical Calculations of IRAS data and provide further evidence of IRAS as all in situ analytical tool with quantification Capability. The ZnO growth followed the logarithmic rate law as predicted by Fehlner and Mott [Oxid. Met., 2, 59 (1970)], QC 20100525

As part of a broader research program dealing with initial atmospheric corrosion of metals induced by organic acids, infrared reflection absorption spectroscopy (IRAS) has been used to study the initial interaction of acetic acid with zinc in 90% relative humidity and 120 ppb acid concentration under in situ condition. Efforts were made to quantify the identified reaction product species, mainly zinc oxide and zinc acetate. The experimentally obtained results were quantified through calculations using a linear relationship between IRAS peak intensity and layer thickness, and assuming optical constants of zinc acetate dihydrate (Zn(CH 3COO) 2•2H 2O). In all, the in situ studies performed by IRAS provide information on the identity and quantity of reaction products formed., QC 20141014

Several previous studies have addressed pheromone communication in various flour beetles (Coleoptera: Tenebrionidae), including the confused flour beetle, Tribolium confusum (du Val). Different stereoisomers of 4,8-dimethyldecanal (DMD) were reported as the only components of an aggregation pheromone, but the behavioral activity of DMD is low. In the present study, additional previously reported secondary metabolites (benzoquinones and hydrocarbons) were tested for electrophysiological activity (EAG) with both sexes of T. confusum. Two benzoquinones and three monoenic hydrocarbons elicited significant EAG activity from both male and female antennae. There was an elevated male EAG response (vs. the females) to two out of the three hydrocarbons and for both quinones. The EAG-active compounds were subsequently investigated for behavioral activity in a walking bioassay. Benzoquinones are considered toxic and have been assigned a function as alarm substances in flour beetles, but we found that methyl-1, 4-benzoquinone in intermediate concentrations was attractive to both male and female beetles and could therefore act as an aggregation pheromone component. Males were also attracted to ethyl-1,4-benzoquinone. The corresponding hydroquinones, presumed precursors of the benzoquinones, did not elicit any electrophysiological response and were not tested for behavioral activity. The unsaturated hydrocarbons (1-tetradecene, 1-pentadecene, and 1-hexadecene) elicited significant EAG responses from both male and female antennae and were also attractive in the behavioral assay. Our results show that several beetle-produced compounds, in addition to 4,8-dimethyldecanal, may be part of a complex pheromone system in flour beetles and play a role in mediating aggregation in T. confusum.

The atmospheric corrosion of pure copper has been investigated after the deposition of sodium chloride (NaCI) particles and exposure to humid air containing gaseous pollutants. Microgravimetry, Fourier transform infrared (FTIR) micro-spectroscopy, and scanning electron microscopy with x-ray microanalysis were used for the investigation of corrosion processes and products. The effect of NaCl particles on the mass gain was much higher than that of gaseous pollutants. With deposition of NaCl particles on the copper surfaces, the corrosion rate increased significantly, with severe corrosion attack mainly localized to the NaCl particle clusters. A similar corrosion rate was found, however, after exposure to pure humid air and to humid air containing gaseous pollutants, sulfur dioxide (SO2), ozone (O-3), nitrogen dioxide (NO2), and SO2 + NO2. The corrosion rate was not dependent on the concentration of the pollutants. However, this was not the case for the combination of SO2 and O-3, leading to a significantly higher corrosion rate at higher concentrations. Exposure of copper samples with NaCl particles deposited resulted in unevenly distributed corrosion product clusters, with a distribution of corrosion products that could be associated with the locations of the particle clusters. Around the particle clusters, the corrosion resulted in areas with different amounts of corrosion products. After 10 days of exposure to humid air containing 100 ppb SO2 and 100 ppb NO2 + SO2, cuprite (Cu2O), paratacamite (Cu-2[OH](3)Cl), carbonate (CO32-), and sulfate (SO42-) were observed mainly in the area of the original particle cluster, with some sutfate and copper hydroxysulfate also in the areas outside. After 10 days of exposure to humid air containing 100 ppb O-3 + SO2, cuprite (Cu2O), hydroxychloride (maybe paratacamite, Cu-2[OH](3)Cl), carbonate (CO32-), and sutfate (SO42-) were observed in the area of the original particle cluster. A circular zone containing brochantite (Cu-4[OH](, QC 20100903. Uppdaterad från Accepted till Published (20100903)

The effect of carbon dioxide (CO2) on sodium chloride (NaCl) induced atmospheric corrosion of copper was studied in laboratory exposures using microgravimetry, ion chromatography, Fourier transform infrared spectroscopy, and scanning electron microscopy with X-ray microanalysis. With lower amount of NaCl particles on the copper surface (< 15 mu g/cm(2)), the corrosion rate was higher with < 1 ppm CO2 than with 350 ppm CO2, and for higher amount of NaCl (> 15 mu g/cm(2)), the corrosion was higher with 350 ppm CO2. With lower amount of NaCl and low CO2 concentration, a secondary spreading of electrolyte occurred from the droplets that formed at the particle clusters. This led to a larger effective cathodic area and a higher corrosion rate. However, at higher surface concentration of NaCl a spatial interaction effect between the local corrosion sites counteracted the increase in the corrosion rate due to overlap of the cathodic areas from the particles. Another factor, which influenced the corrosion process, was the effect of CO2 on the pH of the surface electrolyte. Higher pH (< 1 ppm CO2 concentration) increased the formation of CuO, which improved the corrosion resistance of the corrosion product layer but hindered the formation of insoluble CuCl, whereby more soluble chloride ions were available for triggering localized corrosion and accelerating the initial atmospheric corrosion of copper. Hence, the overall influence of CO2 and NaCl depends on at least three identified mechanisms., QC 20100525

The initial SO2-induced atmospheric corrosion of copper deposited with NaCl has been examined with Fourier transform infrared microspectroscopy under in situ and ex situ conditions in order to reveal the spatial distribution of reaction products. The oxidation of S(IV) turns out to be fast at the area of the NaCl-containing electrolyte droplet, and both sulfate (SO42-) and dithionate (S2O62-) ions form. A copper-catalyzed reaction route for the sulfite oxidation has been suggested, which includes the formation of a Cu(II)-sulfito complex as an important step. The presence of gaseous oxidants such as NO2 and O-3 has previously been considered as an important prerequisite for the oxidation of sulfite on copper. The results obtained here suggest that the formation of local electrochemical cells induced by deposited NaCl particles could be another important route for S(IV) oxidation to sulfate formation. SO2 was found to promote the formation of less soluble paratacamite [Cu-2(OH)(3)Cl] and nantokite (CuCl), which may slow down the atmospheric corrosion rate of copper., QC 20100525

The effect of carbon dioxide (CO2) on the NaCl-induced atmospheric corrosion of copper was studied using in situ Fourier transform infrared microspectroscopy, in situ scanning Kelvin probe, and scanning electron microscopy/energy-dispersive analysis by X-ray. The copper surface was contaminated with a single NaCl particle and then exposed to 80 +/- 2% relative humidity clean humidified air with two concentrations of CO2 (< 5 and 350 ppm). After formation of an electrolyte droplet secondary spreading of electrolyte from the peripherical parts of the droplet was observed. The secondary spreading effect, which was much larger at < 5 ppm CO2 than at 350 ppm, was a consequence of the formation of a galvanic element between a local cathode outside the edge of the droplet and an anode in the droplet. This lead to alkaline conditions in the secondary spreading area and transport of Na+ ions to the local cathode. The large secondary spreading at low CO2 concentration was possible due to lowering of the surface tension of the electrolyte/metal oxide interface at the peripheral parts of the droplet. Carbonate formation lowered the pH when the CO2 concentration was 350 ppm and resulted in a decrease of the pH and inhibition of the secondary spreading., QC 20100525

The atmospheric corrosion of copper has been investigated after deposition of sodium chloride (NaCl) particles and 10 days of subsequent exposure to clean, humidified air below, near, and above the point of deliquescence of NaCl (at around 75% relative humidity (RH), Microgravimetry, Fourier transform infrared (FTIR) microspectroscopy, scanning electron microscopy with x-ray microanalysis, and scanning Kelvin probe were used to identify corrosion processes and products. The NaCl deposition resulted in the evenly distributed NaCl particle clusters with a diameter of approximately 100 μm. The clusters consisted of individual NaCl particles of <10 μm. The mass gain increased linearly with the amount of NaCl particles added in the range of this study (up to 4 μg/cm2). Even at very low RH (55%), which lies far below the point of deliquescence (75%), copper with NaCl particles added suffered from significant corrosion attack and the mass gain of copper with 4 μg/cm2 NaCl added was about 7 μg/cm2 after 10 days of exposure. At 55% RH, the NaCl particles did not dissolve. However, significant chloride-induced corrosion effects were observed after 10 days, both in the original particle cluster and in a 20-μm-wide outer zone into which chloride ions had dffused radially. At 75% RH, the NaCl particles dissolved and chloride ions diffused to cover the whole surface. Chloride-accelerated corrosion effects resulted in the formation of cuprite (Cu2O) and copper carbonate, mainly in the area of the original particle cluster. The corrosion effects accelerated further at 95% PH, resulting in the formation of Cu2O over the whole surface and copper carbonate in a concentric zone outside the original particle cluster. The distribution of the corrosion products was related to the localization of the anodic and cathodic reactions during the corrosion process., QC 20100909