Temperature Vapor Pressure Research Articles

Association of the incidence of atopic dermatitis until 3 years old with climate conditions in the first 6 months of life: Japan Environment and Children's Study (JECS).

To determine the climate conditions that affect the incidence of atopic dermatitis from infancy to 3 years old. We analyzed 100,303 children born from 2011 to 2014 for follow-up until 3 years old using cohort data from the Japan Environment and Children's Study. The study included 15 Regional Centers, including 19 prefectures across Japan. We used meteorological data of the Japan Meteorological Agency. We calculated the hazard ratio (HR) of the standard deviation and low vs. high mean values of several climate conditions in children in their first 6 months of life to determine the incidence of atopic dermatitis. The Kaplan-Meier curve showed that children born in the months of October to December had the highest incidence of atopic dermatitis. Among climate conditions, a one standard deviation increase in the temperature (HR = 0.87), minimum temperature (HR = 0.87), and vapor pressure (HR = 0.87) showed the lowest HRs for the incidence of atopic dermatitis. These results were confirmed by an analysis by strata of the birth season. A low vapor pressure (HR = 1.26, p<0.0001) and the combination of a low mean temperature or low mean minimum temperature and low vapor pressure (HR = 1.26, p<0.0001) were associated with the highest incidence of atopic dermatitis. These results were consistent when they were adjusted for a maternal and paternal history of allergy and the prefecture of birth. Among climate conditions, a low vapor pressure is the most strongly associated with a high incidence of atopic dermatitis. Measuring vapor pressure may be useful for preventing atopic dermatitis.

The Effect of Convective Injection of Ice on Stratospheric Water Vapor in a Changing Climate

AbstractStratospheric water vapor affects the Earth's radiative balance and stratospheric chemistry, yet its future changes are uncertain and not fully understood. The influence of deep convection on stratospheric water vapor remains subject to debate. This letter presents a detailed process‐based model study of the impact of convective ice sublimation on stratospheric water vapor in response to CO2 forced climate change. The influence of convective injection is found to be limited by the vertical profile of temperature and saturation vapor pressure in the tropical tropopause layer, not by the frequency of occurrence. Lagrangian trajectory analysis shows the relative contributions to stratospheric water vapor from sublimation and large‐scale transport are approximately unchanged when CO2 is increased. The results indicate the role of convective ice injection for stratospheric water vapor in a warmer climate remains constrained by large‐scale temperatures.

Thermochemistry of substituted benzenes: acetophenones with methyl, ethyl, cyano and acetoxy substituents

The enthalpies of vaporization/sublimation of 2-, 3- and 4-methyl-acetophenones and 2-, 3-, 4-cyano-acetophenones were derived from the vapor pressure temperature dependence measured with help of the gas saturation method. Enthalpies of fusion of 4-methyl-acetophenone and 2-, 3- and 4-cyano-acetophenone were measured by using DSC. The literature thermochemical data for methyl-, ethyl, cyano- and acetoxy-substituted acetophenones and new results were evaluated using structure–property correlations. The G* quantum chemical methods were validated for reliable estimation of the enthalpies of formation of substituted acetophenones in the gaseous state. The evaluated thermodynamic data were used to design the “centerpiece” method for the assessment of enthalpies of formation and enthalpies of vaporization of substituted benzenes.Graphical abstract

Effects of climatic factors on the prevalence of influenza virus infection in Cheonan, Korea.

Big data can be used to correlate diseases and climatic factors. The prevalence of influenza (flu) virus, accounting for a large proportion of respiratory infections, suggests that the effect of climate variables according to seasonal dynamics of influenza virus infections should be investigated. Here, trends in flu virus detection were analyzed using data from 9,010 tests performed between January 2012 and December 2018 at Dankook University Hospital, Cheonan, Korea. We compared the detection of the flu virus in Cheonan area and its association with climate change. The flu virus detection rate was 9.9% (894/9,010), and the detection rate was higher for flu virus A (FLUAV; 6.9%) than for flu virus B (FLUBV; 3.0%). Both FLUAV and FLUBV infections are considered an epidemic each year. We identified 43.1% (n = 385) and 35.0% (n = 313) infections in children aged < 10years and adults aged > 60years, respectively. The combination of these age groups encompassed 78.1% (n = 698/894) of the total data. Flu virus infections correlated with air temperature, relative humidity, vapor pressure, atmospheric pressure, particulate matter, and wind chill temperature (P < 0.001). However, the daily temperature range did not significantly correlate with the flu detection results. This is the first study to identify the relationship between long-term flu virus infection with temperature in the temperate region of Cheonan.

Exploring the Influence of Seasonal Cropland Abandonment on Evapotranspiration and Water Resources in the Humid Lowland Region, Southern China

AbstractSeasonal abandonment in the previously rice‐based rotation system is increasingly prevalent worldwide particularly in southern China. Assessing the effect of this abandonment on evapotranspiration (ET) and water resources is of major importance for regional water cycle change and agricultural water management. This study analyzed the ET characterization of rice‐winter rape and rice‐winter fallow rotation systems and its relation to weather factors in a humid lowland region, southern China based on a half‐hourly ET measurement with Bowen ratio energy balance system from 2017 to 2020. Then the strategic modeling experiment combining ET and rainfall‐runoff models was used to explore the land abandoning effect on ET and water resources. The results showed that the daily ET values of the rice, rape, and fallow seasons were 3.30 ± 1.89, 1.31 ± 1.31, and 1.55 ± 1.19 mm/d, respectively. The averaged summed ET values of the rice‐winter rape and rice‐fallow rotation systems were 652.3 and 737.8 mm, respectively. Net radiation (Rn) was identified as the most critical weather factor for ET of all seasons. Air temperature and water vapor pressure deficit mainly affected ET indirectly through the path of Rn. Compared with the previously winter rape, the change in daily ET caused by seasonal abandonment was 0.13 ± 0.11 mm/d. This abandonment‐induced ET change increased the average daily storage deficit by 12.0% and groundwater depth by 4.5%, while reduced the daily runoff by 20.3%.

Extension of Kelvin’s equation to dipolar colloids

Vapor pressure refers to the pressure exerted by the vapor phase in thermodynamic equilibrium with either its liquid or solid phase. An important class of active matter is field-driven colloids. A suspension of dipolar colloids placed in a high-frequency rotating magnetic field undergoes a nonequilibrium phase transition into a dilute and dense phase, akin to liquid–vapor coexistence in a simple fluid. Here, we compute the vapor pressure of this colloidal fluid. The number of particles that exist as the dilute bulk phase versus condensed cluster phases can be directly visualized. An exponential relationship between vapor pressure and effective temperature is determined as a function of applied field strength, analogous to the thermodynamic expression between vapor pressure and temperature found for pure liquids. Additionally, we demonstrate the applicability of Kelvin’s equation to this field-driven system. In principle, this appears to be in conflict with macroscopic thermodynamic assumptions due to the nonequilibrium and discrete nature of this colloidal system. However, the curvature of the vapor–liquid interface provides a mechanical equilibrium characterized by interfacial tension that connects the condensed clusters observed with these active fluids to classical colligative fluid properties.

A Computational and Experimental View of Hydrogen Bonding in Glycerol Water Clusters.

Polyol-water clusters provide a template to probe ionization and solvation processes of paramount interest in atmospheric and interstellar chemistry. We generate glycerol water clusters in a continuous supersonic jet expansion and interrogate the neutral species with synchrotron-based tunable vacuum ultraviolet photoionization mass spectrometry. A series of glycerol fragments (m/z 44, 61, 62, and 74) clustered with water are observed. A judicious combination of backing pressure, nozzle temperature, and water vapor pressure allows for tuning the mol % of glycerol. The recorded appearance energies of the water cluster series m/z 62 and 74 are similar to that observed in pure glycerol, while the m/z 61 series shows a dependence on cluster composition. Furthermore, this series also tracks the water concentration of the beam. Theoretical calculations on neutral and ionized clusters visualize the hydrogen bond network in these water clusters and provide an assessment of the number of glycerol-glycerol, glycerol-water, and water-water hydrogen bonds in the cluster, as well as their interaction energies. This method of bond counting and interaction energy assessment explains the changes in the mass spectrum as a function of mol % and offers a glimpse of the disruption of the hydrogen bond network in glycerol-water clusters. The calculations also reveal interesting barrierless chemical processes in photoionized glycerol water clusters that are either activated or do not occur without the presence of water. Examples include spontaneous intramolecular proton transfer within glycerol to form a distonic ion, nonactivated breaking of a C-C bond, and spontaneous proton transfer from glycerol to water. These results appear relevant to radiation-induced chemical processing of alcohol-water ices in the interstellar medium.

Reversible storage and release of hydrogen with LOHC: Evaluation of thermochemical data for methyl-quinolines with complementary experimental and computational methods

The liquid organic hydrogen carriers (LOHC) are aromatic molecules, which can be considered as an attractive option for the storage and transport of hydrogen. A considerable amount of hydrogen can be loaded and unloaded with a reversible chemical reaction. Methyl-substituted quinolines are available from petroleum, coal processing, wood preservation or they can be synthesized from aniline. Quinolines can be considered as potential LOHC systems, provided they have favorable thermodynamic properties, which were the focus of this current study. The absolute vapor pressures of methyl-quinolines were measured using the transpiration method. The standard molar enthalpies of vaporization of methyl-quinolines were derived from the vapor pressure temperature dependences. Thermodynamic data on vaporization and formation enthalpies available in the literature were collected, evaluated, and combined with own experimental results. The theoretical standard molar gas-phase enthalpies of formation of methyl-quinolines, calculated using the quantum chemical G3MP2 and G4 methods, agreed well with the evaluated experimental data. The hydrogenation/dehydrogenation reaction enthalpies of methyl-quinolines were calculated and compared with the data for other potential liquid organic hydrogen carriers. The comparatively low enthalpies of reaction make these heteroaromatics a seminal LOHC systems.

A consistent formation free energy definition for multicomponent clusters in quantum thermochemistry

Quantum chemical calculations have proven to describe the thermodynamics of sub-nanometre clusters more accurately than the liquid drop model used in classical nucleation theory (CNT). However, the standard quantum chemical free energies of multicomponent clusters are fundamentally incompatible with the quantity appearing in the exponential of the CNT expression for the nucleation rate. The origin of this incompatibility is known to be in the statistical thermochemistry, but it is also connected to a much debated issue of self-consistency within CNT. Although these issues do not affect the main results of previous theoretical studies of nucleation, a thorough analysis and discussion about the nature of free energy in quantum chemistry of cluster formation has been missing. In this study, we present a consistent definition for the formation free energy using the law of mass action and a general equilibrium cluster distribution function, and apply this definition to gas-phase quantum thermochemical calculations. This internal consistency allows us to integrate the high-level thermochemical data to the basic framework of CNT and the liquid drop model contained therein. Moreover, based on our analysis, we derive a simple analytical expression for the steady-state nucleation rate compatible with the widely used numerical acdc model. As an illustrative example, the consistent formation free energies and nucleation rates are presented and analysed for atmospherically relevant H2SO4–NH3 clusters at various temperature and monomer vapour pressure conditions.

Microclimate and Plant Transpiration of Tomato (Solanum lycopersicum L.) in a Sunken Solar Greenhouse in North China

The solar greenhouse is a common protected structure for crop production when ambient temperatures are low. In the North China Plain (NCP) winter temperatures are very low and an improved solar greenhouse with a lowered soil surface (0.5–1.5 m deep), referred to as a sunken solar greenhouse (SSG), is used. A four-season experiment was conducted in a commercial SSG with tomato crops to characterize internal microclimate, sap flow (SF) and crop coefficients. Results show that temperature inside the SSG could be more than 20 °C higher than outside in winter, which favors tomato growth and resulted in acceptable yields. Daily total SF was related to solar radiation, vapor pressure deficit (VPD) and temperature, in that order, both in winter and summer. The decoupling coefficient (which is the ratio of radiative to aerodynamic influences on evapotranspiration) in daytime was 0.76 in winter and 0.84 in summer, indicating strong decoupling (i.e., predominance of radiative influences) of the internal environment where wind speed was low. Basal crop coefficients at the mid stage of crop growth averaged 1.15–1.43 in winter and 0.91–0.92 in spring and summer. Thus, in the SSG, for similar climatic conditions sap flow in winter was higher than that in summer, which should be considered in irrigation scheduling.

Molecular versus ionic liquids: Development of a thermodynamic framework for predicting vaporization thermodynamics

Ionic liquids based on the pyridinium and quinolinium cations show good result in desulfurization of fuels. The knowledge of their vaporisation thermodynamics is of practical importance. The standard molar enthalpies of vaporization of pyridinium based ionic liquids were derived from the vapor pressure temperature dependences measured by the quartz-crystal microbalance method. We have collected available primary experimental results on vapour pressures, and enthalpies of phase transitions (solid-solid, crystal-gas, and liquid-gas) of analogous molecular species – substituted pyridines and quinolines. These data were evaluated using the structure-property correlations. The consistent sets of evaluated thermodynamic data on the molecular and ionic liquids were used to develop the “centerpiece” based group-additivity method for predicting enthalpies of vaporization of molecular and ionic compounds. The general transferability of the contributions to the enthalpy of vaporization from the molecular liquids to the ionic liquid has been established.

Characteristic of Stomatal Conductance and Optimal Stomatal Behaviour in an Arid Oasis of Northwestern China

Stomatal conductance (gs), the process that governs plant carbon uptake and water loss, is fundamental to most Land Surface Models (LSMs). With global change accelerating, more attention should be paid to investigating stomatal behavior, especially in extremely arid areas. In this study, gas exchange measurements and environmental/biological variables observations during growing seasons in 2016 and 2017 were combined to investigate diurnal and seasonal characteristics of gs and the applicability of the optimal stomatal conductance model in a desert oasis vineyard. The results showed that the responses of gs to environmental factors (photosynthesis active radiation, PAR; vapor pressure deficit, VPD; and temperature, T) formed hysteresis loops in the daytime. The stomatal conductance slope, g1, a parameter in the unified stomatal optimal model, varied in different growing seasons and correlated with the soil-to-leaf hydraulic conductance (KL). These results indicated the potential bias when using a constant g1 value to simulate gs and highlighted that the water-use strategy of oasis plants might not be consistent throughout the entire growing season. Our findings further help to achieve a better understanding of stomata behavior in responding to climate change and encourage future efforts toward a more accurate parameterization of gs to improve the modeling of LSMs.

Variation in Leaf Morphological Traits of European Beech and Norway Spruce Over Two Decades in Switzerland

Leaf morphological traits (LMTs) of forest trees have been observed to vary across space and species. However, long-term records of LMTs are scarce, due to a lack of measurements and systematic leaf archives. This leaves a large gap in our understanding of the temporal dynamics and drivers of LMT variations, which may help us understand tree acclimation strategies. In our study, we used long-term LMT measurements from foliar material collections of European beech (Fagus sylvatica) and Norway spruce (Picea abies), performed every second year from 1995 to 2019 on the same trees within the Swiss Long-term Forest Ecosystem Research Program LWF. The 11 study plots (6 beech, 4 spruce, and 1 mixed) are distributed along gradients of elevation (485–1,650 m a.s.l.), mean annual precipitation (935–2142 mm), and mean annual temperature (3.2–9.8°C). The investigated LMTs were (i) leaf or needle mass, (ii) leaf area or needle length, and (iii) leaf mass per area or needle mass per length. We combined this unique data set with plot variables and long-term data on potential temporal drivers of LMT variations, including meteorological and tree trait data. We used univariate linear regressions and linear mixed-effects models to identify the main spatial and temporal drivers of LMT variations, respectively. For beech LMTs, our temporal analysis revealed effects of mast year and crown defoliation, and legacy effects of vapor pressure deficit and temperature in summer and autumn of the preceding year, but no clear long-term trend was observed. In contrast, spruce LMTs were mainly driven by current-year spring conditions, and only needle mass per length showed a decreasing long-term trend over the study period. In temporal models, we observed that LMTs of both species were influenced by elevation and foliar nutrient concentrations, and this finding was partly confirmed by our spatial analyses. Our results demonstrate the importance of temporal analysis for determining less recognized drivers and legacy effects that influence LMTs, which are difficult to determine across space and species. The observed differences in the temporal drivers of beech and spruce LMTs suggest differences in the adaptation and acclimation potential of the two species.

Using hybrid modelling to predict basal area and evaluate effects of climate change on growth of Norway spruce and Scots pine stands

ABSTRACT When modelling forest growth, capturing the effects of climate change is needed for reliable long-term predictions and management choices. This remains a challenge because commonly used mensurational forest growth and yield models, relying on inventory data, cannot account for climate change effects. We developed hybrid physiological/mensurational basal area growth and yield models, which combine physiological response to climatic conditions and empirical relations. We included climate and site effects by replacing time with light sums of photosynthetically active radiation and modifying the latter with monthly soil water, vapour pressure deficit, temperature, and frost days. When parameterised with permanent sample plot data for Scots pine and Norway spruce across Sweden, the hybrid models could reproduce observations well, although with no increase in precision compared with time-based mensurational models. When considering different climate scenarios, a significant impact on productivity from climate change emerged. For example, a 2 °C warming enhanced Scots pine production by up to 14% in regions where temperatures were originally cooler and soil water deficit was low (i.e. northwest Sweden), but depressed it, up to 9%, elsewhere. Hence, climate-sensitive models that take local variations into account are necessary for accurate predictions and sustainable forest management.

Growth regimes of aluminium nitride films on hybrid SiC/Si(111) substrates

The nucleation mechanism of aluminum nitride films grown by the method of hydride vapor phase epitaxy on hybrid substrates 3C-SiC/Si(111) is theoretically analyzed. The temperature regions and vapor pressure regions of components are determined in which the island growth mechanism and the layer-by-layer growth mechanism are realized. The theoretical conclusions are compared with the experimental data. The morphology of aluminum nitride film on 3C-SiC/Si(111) at the initial growth stage is investigated by the method of scanning electron microscopy. The methods of controlling the change of the growth mechanism from the island growth to the layer-by-layer growth are proposed. Keywords: aluminium nitride, gallium nitride, silicon carbide on silicon, method HVPE, nucleation, wide-bandgap semiconductors, heterostructures.

Режимы роста пленок нитрида алюминия на гибридных подложках SiC/Si(111)

The nucleation mechanism of aluminum nitride films grown by the method of hydride vapor phase epitaxy on hybrid substrates 3C-SiC/Si(111) is theoretically analyzed. The temperature regions and vapor pressure regions of components are determined in which the island growth mechanism and the layer-by-layer growth mechanism are realized. The theoretical conclusions are compared with the experimental data. The morphology of aluminum nitride film on 3C-SiC/Si(111) at the initial growth stage is investigated by the method of scanning electron microscopy. The methods of controlling the change of the growth mechanism from the island growth to the layer-by-layer growth are proposed.

Carbon reservoirs in shade-tolerant morphotype of Paubrasilia echinata are more susceptible to humidity and temperature changes than sun-tolerant morphotype

Given the eminent climate changes and the importance of carbon dynamics in the growth and survival of plants, we investigated how the non-structural carbohydrates – NSC – and cell wall polymers – CWP (cellulose, hemicellulose, and lignin) – from sun-tolerant and shade-tolerant plants will respond to changes in vapor pressure deficit (VPD) and temperature (temp.) of atmosphere predicted for the southeast region of Brazil for the next decades. We used plants of two morphotypes of Paubrasilia echinata as a biological model. This species presents intraspecific variations from each other in leaf morphology and growth concerning luminosity in the initial phase of growth. The small morphotype is shade-tolerant and the medium morphotype is tolerant to full sun. The work was carried out in greenhouses adjusted with the combination of the higher and lower VPD and temp., constituting 4 enviroments: 1) 0.4 KPa – 19.8 °C, 2) 0.5 KPa – 23.8 °C, 3) 2.0 KPa – 25.1 °C, and 4) 1.1 KPa – 14.9 °C. On day 125 after the start of the experiment, we determined the concentrations of NSC and CWP in the root, stem, and leaves. The shade-tolerant morphotype showed an increase in sugar concentration in the environment where the plants grew the most (2.0 KPa – 25.1 °C). In this same environment, the NSC concentrations of the shoot organs increased in the sun-tolerant morphotype. The 0.4 KPa – 19.8 °C reduced the cellulose and lignin concentrations of the shade-tolerant morphotype and promoted the hemicelluloses of the sun-tolerant morphotype. The NSC and CWP allocation proved to be more influenced by VPD and temp. variations in the shade-tolerant than the sun-tolerant morphotype. We conclude that warming and lower atmospheric humidity could inhibit the axial stem growth of sun-tolerant juvenile plants. Warming, regardless of atmospheric humidity variations, will not affect the cellulose and lignin levels of stem, and consequently, the wood quality of shade- and sun-tolerant plants. However, hemicelluloses concentrations of sun-tolerant plants may decline in a warmer and less humid atmosphere.

Characteristic Decrease in the Value of Rapeseed Evapotranspiration after Its Ripening

This paper presents the methodology of taking measurements of active surface energy balance components using the Bowen method. It discusses the applied measurement system, an important part of which are HMD 50U/50Y measurement sensors from Vaisala, adapted to work in the field. Their operation is a source of data for determining vertical profiles of temperature and water vapour pressure. These data are used to determine the turbulence components of the energy balance, i.e., sensible and latent heat. Measurements taken during the vegetative season on rape field showed that intensive evaporation occurred in the period until the end of June and that its decrease coincided with the decrease in the value of the degree of plant development determined on the basis of LAI records. In spring, during the period of intensive plant development, the decade sums of evaporation reached 30 mm, after which their quantities fell to the range of 10–15 mm. They became higher only in the periods of precipitation, when the water from the interception was available.

Hydrogen Storage: Thermodynamic Analysis of Alkyl-Quinolines and Alkyl-Pyridines as Potential Liquid Organic Hydrogen Carriers (LOHC)

The liquid organic hydrogen carriers (LOHC) are aromatic molecules, which can be considered as an attractive option for the storage and transport of hydrogen. A considerable amount of hydrogen up to 7–8% wt. can be loaded and unloaded with a reversible chemical reaction. Substituted quinolines and pyridines are available from petroleum, coal processing, and wood preservation, or they can be synthesized from aniline. Quinolines and pyridines can be considered as potential LOHC systems, provided they have favorable thermodynamic properties, which were the focus of this current study. The absolute vapor pressures of methyl-quinolines were measured using the transpiration method. The standard molar enthalpies of vaporization of alkyl-substituted quinolines and pyridines were derived from the vapor pressure temperature dependencies. Thermodynamic data on vaporization and formation enthalpies available in the literature were collected, evaluated, and combined with our own experimental results. The theoretical standard molar gas-phase enthalpies of formation of quinolines and pyridines, calculated using the quantum-chemical G4 methods, agreed well with the evaluated experimental data. Reliable standard molar enthalpies of formation in the liquid phase were derived by combining high-level quantum chemistry values of gas-phase enthalpies of formation with experimentally determined enthalpies of vaporization. The liquid-phase hydrogenation/dehydrogenation reaction enthalpies of alkyl-substituted pyridines and quinolines were calculated and compared with the data for other potential liquid organic hydrogen carriers. The comparatively low enthalpies of reaction make these heteroaromatics a seminal LOHC system.

Modifying root-to-shoot ratio improves root water influxes in wheat under drought stress.

Drought intensity as experienced by plants depends upon soil moisture status and atmospheric variables such as temperature, radiation, and air vapour pressure deficit. Although the role of shoot architecture with these edaphic and atmospheric factors is well characterized, the extent to which shoot and root dynamic interactions as a continuum are controlled by genotypic variation is less well known. Here, we targeted these interactions using a wild emmer wheat introgression line (IL20) with a distinct drought-induced shift in the shoot-to-root ratio and its drought-sensitive recurrent parent Svevo. Using a gravimetric platform, we show that IL20 maintained higher root water influx and gas exchange under drought stress, which supported a greater growth. Interestingly, the advantage of IL20 in root water influx and transpiration was expressed earlier during the daily diurnal cycle under lower vapour pressure deficit and therefore supported higher transpiration efficiency. Application of a structural equation model indicates that under drought, vapour pressure deficit and radiation are antagonistic to transpiration rate, whereas the root water influx operates as a feedback for the higher atmospheric responsiveness of leaves. Collectively, our results suggest that a drought-induced shift in root-to-shoot ratio can improve plant water uptake potential in a short preferable time window during early morning when vapour pressure deficit is low and the light intensity is not a limiting factor for assimilation.