Low Relative Humidity Values Research Articles

Optical characterization and thermal performance of a novel solar dryer with dynamic control of solar radiation

In this study, a novel adaptive solar dryer with a coating of polymer-dispersed liquid crystals (PDLC) was designed, built, and characterized to evaluate its optical properties and thermal performance by modulating the transmission of solar radiation toward the drying chamber. PDLC films can electrically switch between opaque and transparent states, making them ideal for controlling solar radiation. Unlike conventional direct dryers, the proposed solar drying system takes advantage of direct solar radiation, known for its rapid drying process, while minimizing the impact on product properties. The results show that the PDLC coating exhibited a significant difference in transmittance between the “on” and “off” states under ambient conditions. At 400 nm, the transmittance varied by 20 %, increasing to 30 % at 450 nm. The solar dryer with dynamic control of solar irradiance constantly maintained a temperature range of 52.19 °C–57 °C. Lower relative humidity values were achieved compared to the uncontrolled solar dryer, resulting in a uniform irradiance distribution within the drying cabinet. The solar dryer with dynamic control of solar irradiance (acrylic and PDLC film) presents a total thermal resistance (0.02817 mK/W) exhibiting better heat permanence inside the drying cabinet compared to polycarbonate (one of the materials most used for drying systems). The system's thermal efficiency ensures reliable operation regardless of weather conditions, efficiently capturing and converting solar energy into heat.

Sintering and exploitation properties of humidity-sensitive nanostructured ceramics and thick films based on MgAl2O4 spinel

The electrophysical properties of nanostructured MgAl2O4 ceramics sintered at 1300 °C for 5 h, as well as thick films were obtained and investigated. The study of adsorption-desorption cycles was carried out after sintering and aging test. It is shown that ceramic has a sensitivity to humidity in the range of 25–95% with minimal hysteresis of the characteristic in adsorption-desorption cycles, which can be eliminated after the aging test. Thick films based on it are characterized by hysteresis and loss of sensitivity at low values of relative humidity, which is caused by the clogging of small nanopores.

Genetic Variation and Heritability for Hydrogen Cyanide in Fresh Cassava Roots: Implications for Low-Cyanide Cassava Breeding.

Breeding for low-hydrogen-cyanide (HCN) varieties is a major objective of programs targeting boiled cassava food products. To enhance the breeding of low-HCN varieties, knowledge of genetic variation and trait heritability is essential. In this study, 64 cassava clones were established across four locations and evaluated for HCN using three HCN assessment methods: one with a 1 to 9 scale, on with a 0 ppm to 800 ppm scale, and a quantitative assay based on spectrophotometer readings (HCN_Spec). Data were also collected on the weather variables precipitation, relative humidity, and temperature. Highly significant differences were observed among clones (p < 0.001) and locations (p < 0.001). There was also significant clone-environment interactions, varying from p < 0.05 to p < 0.001. Locations Arua and Serere showed higher HCN scores among clones and were associated with significantly higher (p < 0.001) mean daily temperatures (K) and lower relative humidity values (%) across 12 h and 18 h intervals. Within locations, HCN broad sense heritability estimates ranged from 0.22 to 0.64, while combined location heritability estimates ranged from 0.14 to 0.32. Relationships between the methods were positive and strong (r = 0.75-0.92). The 1 to 9 scale is more accurate and more reproducible than either the 0 to 800 ppm scale or spectrophotometric methods. It is expected that the information herein will accelerate efforts towards breeding for low-HCN cassava varieties.

Dependence on relative humidity in the formation of reactive oxygen species in water droplets

Water microdroplets (7 to 11 µm average diameter, depending on flow rate) are sprayed in a closed chamber at ambient temperature, whose relative humidity (RH) is controlled. The resulting concentration of ROS (reactive oxygen species) formed in the microdroplets, measured by the amount of hydrogen peroxide (H2O2), is determined by nuclear magnetic resonance (NMR) and by spectrofluorimetric assays after the droplets are collected. The results are found to agree closely with one another. In addition, hydrated hydroxyl radical cations (•OH-H3O+) are recorded from the droplets using mass spectrometry and superoxide radical anions (•O2-) and hydroxyl radicals (•OH) by electron paramagnetic resonance spectroscopy. As the RH varies from 15 to 95%, the concentration of H2O2 shows a marked rise by a factor of about 3.5 in going from 15 to 50%, then levels off. By replacing the H2O of the sprayed water with deuterium oxide (D2O) but keeping the gas surrounding droplets with H2O, mass spectrometric analysis of the hydrated hydroxyl radical cations demonstrates that the water in the air plays a dominant role in producing H2O2 and other ROS, which accounts for the variation with RH. As RH increases, the droplet evaporation rate decreases. These two facts help us understand why viruses in droplets both survive better at low RH values, as found in indoor air in the wintertime, and are disinfected more effectively at higher RH values, as found in indoor air in the summertime, thus explaining the recognized seasonality of airborne viral infections.

Optimization of the fan coil cooling system and the air source heat pump using a moderated mediation model

The data obtained from a heating and cooling system comprised of a fan coil unit integrated air source heat pump used in Istanbul, Turkey, as well as data on outdoor conditions, was analyzed in this study. The analysis was carried out with the help of the moderated mediation model, which is included as a process analysis in the ?Statistical Package for the Social Sciences? application. In this study, a mathematical model of the moderated mediation model was created and the efficiency coefficients of the parameters effecting performance were calculated. It was discovered that the effect of medium and high relative humidity values on the outdoor temperature was about 4.81%. The heat pump fails to transmit heat to the environment outside as a result of medium and high relative humidity values increasing the outdoor temperature. As a result of this it has been found that relative humidity values have a negative effect on the water temperature entering the fan coil unit by approximately -1.18%. This result of the study shows that the outlet water temperature of the fan coil unit does not adequately cool the rooms in the summer. It has been discovered that while wind velocity negatively affects performance affecting parameters, low relative humidity values have no effect on them.

Fog and low-level stratus characteristics at the airport of Odesa from surface observations

Introduction. Fog that limits visibility and low-level stratus represent a significant hazard to aviation especially during takeoff and landing, and also low-level flying of aircrafts, because accidents often occur in reduced visibility conditions and low clouds. Therefore, forecasting fog and low ceilings is one of the most important, but at the same time the most difficult issue, because both phenomena strongly depend on local conditions and unsteady in both time and space. The aim of the study is to obtain the statistical characteristics of low-level stratus and fog at the airport of Odessa and determine local dependencies that would enable to improve aviation weather forecasts related to low-level stratus and fog physics. Scientific novelty of results obtained. In this study for the Ukraine for the first time for Odesa airport frequency distribution of low-level stratus and fogs is obtained as a function of the time of the day and the month of the year and also as a function of the temperature and relative humidity near the surface. Practical importance of results obtained. The results obtained could be used for providing weather forecast model with historical data and improving forecast of fogs and low-level stratus. Materials and method. To study fog and low-level stratus characteristics occurring at the airport of Odesa, Ukraine, half hourly observations in the period of 2010-2021 are used. Applying a statistical approach annual, seasonal and diurnal distribution of fog and low stratus and their frequency distribution associated with various meteorological parameters are obtained. Results and discussion. The monthly distributions of low-level stratus reveal maximum occurrence frequencies in November and January, and fog most frequently occurs in December. No significant diurnal cycle of stratiform cloud occurrence is discovered, as opposed to fog for which the highest frequency is observed in the hours before sunrise, while when the day sets in, frequencies are declining and increasing at night. Fog and low-level stratus have the same distribution in duration and the mean event duration is 4.5 h while 55% of the events lasted 2 h or less. The most long-lived fog and stratiform clouds can last about 4 days during the December-January period. Occurrence of fog and stratiform clouds as function of temperature and relative humidity reveals a close statistical relationship, especially for fog events. More than 33% of all fogs are observed at temperatures of 0°C to 6°C and 96-100% relative humidity, the most frequencies of low-level clouds (13%) occur in the same temperature interval, but at lower values of relative humidity (91‑95%). Regarding fog density 75% of the events have minimum visibility lower than 400 m, which indicates the severity of the problem, because, despite the season and type of fog, they are usually quite intense and dense. In all seasons of the year, the highest frequency of low-level stratiform clouds is in interval of 3...4 m/s, excluding summer, when most often such cloud is registered at higher speeds. The wind directions associated with low-level stratiform clouds are, as a rule, northern and eastern ones. Fogs, on the contrary, most often in all seasons, except winter, are formed at calm, meaning that radiation fogs are the most common type in the Odesa airport. In winter fogs are most commonly associated with northern and easterly winds; in all other seasons the southern wind is the most frequent.

Effect of habitat quality on the biodiversity of ant genera and functional groups in a riparian forest area of the Tauarizinho River in Eastern Amazonia

In view of the scenario of human disturbances and regional climate change, we intend to verify whether habitats that are structurally more heterogeneous, complex and of higher quality, such as riparian forests, support a higher biodiversity of ant genera and their respective functional groups, when compared to more homogeneous environments and of low habitat quality such as abandoned pasture areas, as well as the effects of seasonality. A total of 4,865 ants belonging to 7 subfamilies and 15 ant genera were collected. The subfamilies that showed the highest representativeness (abundance) were Myrmicinae (4,436), followed by Formicinae (282), Ectatomminae (97), Dolichoderinae (18), Pseudomyrmecinae (15), Dorylinae (9) and Ponerinae (8). The high-quality habitat, which corresponds to riparian forest, had the highest richness of genera, characterized by the genus Nylanderia, with a higher occurrence of the functional group Generalist Myrmecinae, with high values of relative humidity in both seasons. On the other hand, the low-quality habitat showed less richness of genera, being the genus that caracterizes this environment the Crematogaster, with higher occurrence of the functional group of Tropical Climate Specialists and low values of relative humidity. In view of the above, this study provides subsidies for conservation work in riparian forest areas in the humid tropical forest biome. Besides warning about the reduction in the richness of ant genera due to the conversion of natural areas into pasture.

Interplay between Facets and Defects during the Dissociative and Molecular Adsorption of Water on Metal Oxide Surfaces

Surface terminations and defects play a central role in determining how water interacts with metal oxides, thereby setting important properties of the interface that govern reactivity such as the type and distribution of hydroxyl groups. However, the interconnections between facets and defects remain poorly understood. This limits the usefulness of conventional notions such as that hydroxylation is controlled by metal cation exposure at the surface. Here, using hematite (α-Fe2O3) as a model system, we show how oxygen vacancies overwhelm surface cation-dependent hydroxylation behavior. Synchrotron-based ambient-pressure X-ray photoelectron spectroscopy was used to monitor the adsorption of molecular water and its dissociation to form hydroxyl groups in situ on (001), (012), or (104) facet-engineered hematite nanoparticles. Supported by density functional theory calculations of the respective surface energies and oxygen vacancy formation energies, the findings show how oxygen vacancies are more prone to form on higher energy facets and induce surface hydroxylation at extremely low relative humidity values of 5 × 10-5%. When these vacancies are eliminated, the extent of surface hydroxylation across the facets is as expected from the areal density of exposed iron cations at the surface. These findings help answer fundamental questions about the nature of reducible metal oxide-water interfaces in natural and technological settings and lay the groundwork for rational design of improved oxide-based catalysts.

Kinetics of hypochlorous acid reactions with organic and chloride-containing tropospheric aerosol.

Chlorine plays an important role in tropospheric oxidation processes, in both marine and continental environments. Although modeling studies have explored the importance of halogen chemistry, uncertainty remains in associated chemical mechanisms and fundamental kinetics parameters. Prior kinetics measurements of multiphase halogen recycling reactions have been largely performed with dilute, bulk solutions, leaving unexplored more realistic chemical systems which have high solute concentrations and are internally mixed with both halide and organic components. Here, we address the multiphase kinetics of gaseous HOCl using an aerosol flow tube and aerosol mass spectrometer to study its reactions with particulate chloride, using atmospherically relevant particle acidity, solute concentrations, and ionic strength. We also investigate the chemistry that results when biomass burning (BB) aerosol components and chloride are internally mixed. Using pH-buffered deliquesced particles, we show that the rate constant for reaction of dissolved HOCl with H+ and Cl- at high relative humidity (RH) (80-85%) is within a factor of two of the literature value for bulk phase conditions. However, at lower RH values (60-70%) where the particles are considerably more concentrated, the rate constant for chloride loss from the particles is an order of magnitude higher. For pure organic compounds commonly found in biomass burning (BB) aerosol, such as coniferaldehyde, salicylic acid and furfural, an increase in the aerosol chlorine content occurs with HOCl exposure, indicating the formation of organochlorine species. Together, these independent findings explain results for internally mixed aerosol particles with both chloride and BB components present where we observed behavior consistent with both chloride loss and organochlorine formation occurring simultaneously upon HOCl exposure. Our results indicate that chlorine recycling via HOCl uptake by chloride-containing particles will occur in the atmosphere efficiently over a wide range of RH conditions, even when reactive organic compounds are present in the same particles as chloride. Simultaneously, formation of organochlorine compounds, which are commonly toxic, is likely occurring when reactive organic components are present.

Assessing the impacts of meteorological factors on freshwater consumption in arid regions and forecasting the freshwater demand

The continuously increasing consumption and scarcity of natural freshwater resources impose threats on different aspects of human life. This study investigated the possible influences of meteorological factors, e.g., relative humidity, temperature, and wind speed, on net freshwater consumption (NFWC). Additionally, we determined the seasonal variations in these factors and forecasted the consumption rate over five years. We took Kuwait as an example and analyzed daily readings obtained from 2014 to 2018 by the Directorate General of Civil Aviation and Ministry of Electricity and Water. The results showed that the consumption rate was affected positively by temperature and negatively by relative humidity. In the seasonality results, two groups characterizing the summer (May to October) and winter (November to April) seasons were obtained regarding the corresponding meteorological factors and net freshwater production (NFWP) and NFWC. The summer season showed high temperature, NFWC, and NFWP and low relative humidity values. In contrast, the winter season revealed high relative humidity and low temperature, NFWC, and NFWP values. The forecasting model is highly accurate and estimated that NFWC will reach 171,919 million imperial gallons/year by 2024. Thus, the obtained results and performed analyses assist in the future management and performance of installed desalination processes.

Optimization Algorithms: Optimal Parameters Computation for Modeling the Polarization Curves of a PEFC Considering the Effect of the Relative Humidity

The development of green energy conversion devices has been promising to face climate change and global warming challenges over the last few years. Energy applications require a confident performance prediction, especially in polymer electrolyte fuel cell (PEFC), to guarantee optimal operation. Several researchers have employed optimization algorithms (OAs) to identify operating parameters to improve the PEFC performance. In the current study, several nature-based OAs have been performed to compute the optimal parameters used to describe the polarization curves in a PEFC. Different relative humidity (RH) values, one of the most influential variables on PEFC performance, have been considered. To develop this study, experimental data have been collected from a lab-scale fuel cell test system establishing different RH percentages, from 18 to 100%. OAs like neural network algorithm (NNA), improved grey-wolf optimizer (I-GWO), ant lion optimizer (ALO), bird swarm algorithm (BSA), and multi-verse optimization (MVO) were evaluated and compared using statistical parameters as training error and time. Results gave enough information to conclude that NNA had better performance and showed better results over other highlighted OAs. Finally, it was found that sparsity and noise are more present at lower relative humidity values. At low RH, a PEFC operates under critical conditions, affecting the fitting on OAs.

Confined water radiolysis in aluminosilicate nanotubes: the importance of charge separation effects.

Imogolite nanotubes are potentially promising co-photocatalysts because they are predicted to have curvature-induced, efficient electron-hole pair separation. This prediction has however not yet been experimentally proven. Here, we investigated the behavior upon irradiation of these inorganic nanotubes as a function of their water content to understand the fate of the generated electrons and holes. Two types of aluminosilicate nanotubes were studied: one was hydrophilic on its external and internal surfaces (IMO-OH) and the other had a hydrophobic internal cavity due to Si-CH3 bonds (IMO-CH3), with the external surface remaining hydrophilic. Picosecond pulse radiolysis experiments demonstrated that the electrons are efficiently driven outward. For imogolite samples with very few external water molecules (around 1% of the total mass), quasi-free electrons were formed. They were able to attach to a water molecule, generating a water radical anion, which ultimately led to dihydrogen. When more external water molecules were present, solvated electrons, precursors of dihydrogen, were formed. In contrast, holes moved towards the internal surface of the tubes. They mainly led to the formation of dihydrogen and of methane in irradiated IMO-CH3. The attachment of the quasi-free electron to water was a very efficient process and accounted for the high dihydrogen production at low relative humidity values. When the water content increased, electron solvation dominated over attachment to water molecules. Electron solvation led to dihydrogen production, albeit to a lesser extent than quasi-free electrons. Our experiments demonstrated the spontaneous curvature-induced charge separation in these inorganic nanotubes, making them very interesting potential co-photocatalysts.

Influence of temperature and relative humidity on vapor hydration of an AVM nuclear waste glass

The safety assessment of the geological disposal of nuclear waste glasses requires a thorough understanding of the vapor hydration mechanisms of these glasses. In this context, the effect of temperature and relative humidity on vapor hydration of the AVM6 glass, which is the most reactive among the studied French AVM glasses, was investigated in the present study. Polished glass monoliths were vapor hydrated for 1 year (i) at 97% relative humidity (RH), at temperatures 70°C and 90°C to study the effect of temperature and (ii) at 50°C and 50% RH, 76% RH, 88% RH and 97% RH to study the effect of RH. The altered glass samples were characterized by SEM, XRD and ToF-SIMS. The results were compared with published results of AVM6 glass vapor hydrated at 50°C and 95% RH. The nature of the secondary phases that precipitate varied with both temperature and relative humidity, leading to variation in the behavior of elements in the altered layer (gel) but the altered layer morphology is similar at all temperatures studied. The Arrhenius law for temperature dependence is respected between the temperature range 50–90°C and the activation energy suggests that network-hydrolysis is the predominant rate controlling mechanism at these temperatures and duration. The secondary phases that incorporate transition metals and rare-earth elements are identified by XRD only in experiments conducted at lower RH values.

Natural versus synthetic zeolites for controlling the maize weevil (Sitophilus zeamais)–like Messi versus Ronaldo?

Laboratory experiments were carried out to evaluate the impact of zeolites of different origins on the mortality of the maize weevil (Sitophilus zeamais Motschulsky). We tested the efficacy of natural zeolites (Slovenian and Serbian) and a synthetic zeolite (Asorbio®). Diatomaceous earth (SilicoSec®) was used as a positive control. We applied the zeolites as surface treatments (at concentrations of 10 g/m2 and 20 g/m2) and as admixtures (grain with zeolites) (at concentrations of 450 ppm and 900 ppm). The mortality of the weevils when the zeolites were applied as a surface treatment was evaluated every day until the 7th day after application; delayed mortality was measured every day until the 14th day after application. When the zeolites were admixed, we evaluated mortality after the 7, 14, and 21 days. The research was performed at two different relative humidity values (55 and 75%) and at three different temperatures (15, 20 and 25 °C). We conclude that the mortality of maize weevils was influenced by relatively high temperature and low relative humidity values. There was no impact of the zeolite dose on the mortality of the maize weevils when applied as a surface treatment. The mortality of the weevils was similar in the treatments with the two natural zeolites (Slovenian and Serbian), while the mortality of the maize weevils was the lowest in the treatments with Asorbio®. The use of natural zeolites as a protectant for stored products was shown to be effective in our research, although additional surveys should be conducted.

How significant is the effect of the surface characteristics on the Reference Evapotranspiration estimates?

Estimated Reference Evapotranspiration (ETo), requires the meteorological attributes to be taken above standardized well-watered and vegetation-covered surfaces. However, worldwide such vegetation-reference sites are not common. This results in mistaken estimates of ETo by using the well-known and extensively applied FAO-56 Penman–Monteith formula. Consequently, the use of inappropriate data for ETo estimation from non-ideal surfaces, leads to significant and systematic cumulative errors introducing uncertainties when determining the crop water requirements in a region. Additionally, the existing climatic stations are not spatially distributed but rather concentrated mostly in non-rural urban areas or in local airports, operating above non–standardized surfaces.The purpose of this work is to assess the effect of using daily meteorological data recorded above a well-watered short crop compared to data obtained above dry bare soil, at the same local environment, using two widely used ETo models: the ASCE Penman-Monteith and the Hargreaves-Samani. The results indicate that the meteorological conditions above the different surfaces are quite different, presenting higher temperature and lower relative humidity values above the bare soil surface compared to the well-watered short crop and resulting, finally, to errors in the estimation of reference evapotranspiration. These errors appear to enhance as air temperature, vapor pressure deficit, radiation and atmospheric clearness increases, or relative humidity decreases but are diminishing under adequate soil moisture conditions resulting after rainfall events. The ETo differences vary according to the model each time adopted but the soil substrate influence can be detected by more sophisticated methods, such as FAO56-PM, which consider the energy balance of the surface.

Effect of aerosol composition on the performance of low-cost optical particle counter correction factors

Abstract. There is considerable interest in using low-cost optical particle counters (OPCs) to supplement existing routine air quality networks that monitor particle mass concentrations. In order to do this, low-cost OPC data need to be comparable with particle mass reference instrumentation; however, there is currently no widely agreed upon methodology to accomplish this. Aerosol hygroscopicity is known to be a key parameter to consider when correcting particle mass concentrations derived from low-cost OPCs, particularly at high ambient relative humidity (RH). Correction factors have been developed that apply κ-Köhler theory to correct for the influence of water uptake by hygroscopic aerosols. We have used datasets of co-located reference particle measurements and low-cost OPC (OPC-N2, Alphasense) measurements, collected in four cities on three continents, to explore the performance of this correction factor. We provide evidence that the elevated particle mass concentrations, reported by the low-cost OPC relative to reference instrumentation, are due to bulk aerosol hygroscopicity under different RH conditions, which is determined by aerosol composition and, in particular, the levels of hygroscopic aerosols (sulfate and nitrate). We exploit measurements made in volcanic plumes in Nicaragua, which are predominantly composed of sulfate aerosol, as a natural experiment to demonstrate this behaviour in the ambient atmosphere; the observed humidogram from these measurements closely resembles the calculated pure sulfuric acid humidogram. The results indicate that the particle mass concentrations derived from low-cost OPCs during periods of high RH (&gt;60 %) need to be corrected for aerosol hygroscopic growth. We employed a correction factor based on κ-Köhler theory and observed that the corrected OPC-N2 PM2.5 mass concentrations were within 33 % of reference measurements at all sites. The results indicated that a κ value derived in situ (using suitable reference instrumentation) would lead to the most accurate correction relative to co-located reference instruments. Applying a κ values from the literature in the correction factor also resulted in improved OPC-N2 performance, with the measurements being within 50 % of the reference values. Therefore, for areas where suitable reference instrumentation for developing a local correction factor is lacking, using a literature κ value can result in a reasonable correction. For locations with low levels of hygroscopic aerosols and low RH values, a simple calibration against gravimetric measurements (using suitable reference instrumentation) would likely be sufficient. Whilst this study generated correction factors specific for the Alphasense OPC-N2 sensor, the calibration methodology developed is likely amenable to other low-cost PM sensors.

Are coastal deserts necessarily dew deserts? An example from the Tabernas Desert

Abstract Vapor condensation, whether due to dew or fog, may add a stable and important source of water to deserts. This was also extensively assessed in the Negev, regarded as a dew desert. Dew deserts necessitate a large reservoir of vapor, and are therefore confined to near oceans or seas. Yet, examples of such deserts are scarce. Here we try to assess whether the Tabernas Desert in SE Spain can be regarded as a dew desert, and may therefore facilitate the growth of certain organisms that otherwise would not survive the dry season. We analyze some of the abiotic conditions of four relatively dry months (June, July, August, September) in the Tabernas and Negev deserts (with the Negev taken as an example of a dew desert) during 2003–2012. The analysis showed substantially lower values of relative humidity (by 10–13%) in the Tabernas in comparison to the Negev, with RH ≥95% being on average only 0.9–1.1 days a month in the Tabernas in comparison to 9.7–13.9 days in the Negev. Our findings imply that the Tabernas Desert cannot be regarded as a dew desert, suggesting that rain will be the main factor responsible for the food web chain in the Tabernas.

Comparative survival of the engorged stages of Amblyomma dubitatum and Amblyomma sculptum in the laboratory: Implications for Brazilian spotted fever epidemiology

Brazilian spotted fever (BSF), caused by the bacterium Rickettsia rickettsii, is transmitted to humans mainly by the tick Amblyomma sculptum in southeastern Brazil. In most BSF-endemic areas A. sculptum populations are sustained chiefly by capybaras (Hydrochoerus hydrochaeris), which are also the host of another tick species, Amblyomma dubitatum, not implicated in R. rickettsii transmission. Herein, we evaluated the effects of relative humidity (RH), temperature, and water immersion on the successful development of the engorged stages of A. dubitatum and compared them with recently published data under the same experimental conditions for A. sculptum. We showed that free-living developmental stages (engorged larvae, nymphs and females, and eggs) of A. dubitatum had higher survival rates when these stages were submerged in water for different periods of times (24–72 h). On the other hand, higher survival rates were observed for A. sculptum when ticks were incubated at lower RH values, 65 or 78 %, regardless of summer or winter mean temperatures. These results suggest that A. dubitatum is more adapted to humid habitats and seasonally flooding soils than A. sculptum, whereas this latter species should be more adapted than A. dubitatum to drier habitats. The implications of these results for the spatial distribution of A. dubitatum and A. sculptum, in relation to BSF epidemiology, are discussed.

Effects of solvent vapor annealing on the crystallinity and spin crossover properties of thin films of [Fe(HB(tz)3)2

Abstract We investigated the solvent vapor annealing process of thermally evaporated thin films of the [FeII(HB(tz)3)2] (tz = 1,2,4-triazol-1-yl) spin crossover complex. Using grazing incidence X-ray diffraction, atomic force microscopy, and variable-temperature UV spectrophotometry, we show how the crystallinity, morphology, and spin crossover properties of the resulting films are altered by exposure to vapors of five different solvents: diethyl ether, acetone, dichloromethane, ethanol, and water. Remarkably, most solvents yielded highly oriented crystalline films displaying an abrupt and complete spin transition around 336 K. A notable exception is the case of dichloromethane—suggesting that the solvent ability to accept hydrogen bonding might be a key factor in controlling the film crystallinity. On the other hand, only water vapor treatment affords for smooth and continuous film morphology. The recrystallization process in controlled humidity was thus followed in situ by monitoring the UV absorbance of the films. This study revealed the critical importance of the relative humidity (RH): for values above a threshold of ca. 72% RH (at 298 K) a very fast (seconds) crystallization occurs leading to robust, crystalline films, whereas crystallization at lower RH values is slower (hours) and leads to less stable, semicrystalline films displaying incomplete spin transitions.

User-dependent hygrothermal assessment and material parameter optimization for a wood-based construction under climate conditions of South Korea

Hygrothermal simulation programs are widely used nowadays, but reliable results can only be achieved with the knowledge of input parameter values. This study shows how the difficulties, obtaining accurate material properties and specifying boundary conditions, affect the hygrothermal performance of the construction. A wood-based construction is investigated under climate conditions of South Korea. Sensitive material parameters and boundary conditions, which significantly influence the relative humidity in the construction, are identified by means of the method of Morris. The most influential material parameters are varied for specific boundary conditions using Latin Hypercube sampling, resulting in a wide range of relative humidity values (~51 % until ~99 %) on OSB surface. Low relative humidity values on OSB are obtained with a Pareto-optimal material parameter set.