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Molecular-level nucleation has not been clearly understood due to the complexity of multi-body potentials and the stochastic, rare nature of the process. This work utilizes molecular dynamics (MD) simulations, incorporating a first-principles-based deep neural network (DNN) potential model, to investigate homogeneous water vapor condensation. The nucleation rates and critical nucleus sizes predicted by the DNN model are compared against commonly used semi-empirical models, namely extended simple point charge (SPC/E), TIP4P, and OPC, in addition to classical nucleation theory (CNT). The nucleation rates from the DNN model are comparable with those from the OPC model yet surpass the rates from the SPC/E and TIP4P models, a discrepancy that could mainly arise from the overestimated bulk free energy by SPC/E and TIP4P. The surface free energy predicted by CNT is lower than that in MD simulations, while its bulk free energy is higher than that in MD simulations, irrespective of the potential model used. Further analysis of cluster properties with the DNN model unveils pronounced variations of O–H bond length and H–O–H bond angle, along with averaged bond lengths and angles that are enlarged during embryonic cluster formation. Properties such as cluster surface free energy and liquid-to-vapor density transition profiles exhibit significant deviations from CNT assumptions. [ABSTRACT FROM AUTHOR]

We have developed an experimental and analytical setup for thermal desorption spectroscopy of solid water films on surfaces. We obtain the coverage-dependent desorption kinetics of water molecules from a well-defined ultra-thin alumina/NiAl(110) surface in the coverage range of 0–2 monolayers. We use a novel deconvolution technique to eliminate the pumping delay of water vapor in the vacuum system, which has previously hindered the accurate estimation of desorption kinetic parameters, such as activation energy and pre-exponential factor. The coverage-dependent Arrhenius analysis reveals that the desorption activation energy decreases with increasing coverage in the sub-monolayer range, indicating that the water–water interaction is not attractive. We also find that the pre-exponential factor for the second layer is higher than that for the sub-monolayer. We explain this difference in terms of transition state theory and propose that entropic effects play a significant role in water desorption kinetics. [ABSTRACT FROM AUTHOR]

This article presents methodological advances in the state-of-the-art for making time-dependent, thermochemical measurements within kilogram-scale explosive post-detonation fireballs utilizing tunable laser absorption spectroscopy. This measurement capability is critical for validating multi-scale, multi-physics models of post-detonation dynamics. The technique is based on hardened gauges built around rapidly-tunable lasers and custom post-processing algorithms that provide quantitative thermochemical data interior to large and opaque explosive fireballs. The authors present a holistic overview of the technique including gauge design, the laser absorption diagnostic, and the custom data processing algorithms. Additionally, fielding high-bandwidth laser absorption probes at stand-off ranges presents new challenges in data processing that must compensate for long distance signal transmission effects. We highlight representative data from a hardened gauge measurement at 0.81 m stand-off from a 2.78 kg LX-14 explosive charge detonated in an outdoor test arena. We discuss progress in all-optical measurement of temperature, pressure, and water vapor number density at a 100 kHz repetition rate during the first 10 ms of the fireball evolution. We conclude the article with a brief discussion on our current approach for comparing hardened gauge measurements with computational fluid dynamic simulations. [ABSTRACT FROM AUTHOR]

Using adiabatic molecular dynamics coupled with the fluid dynamics equations, we model nucleation in an expanding beam of water vapor and argon on a microsecond scale. The size distribution of clusters, their temperature, and pickup cross sections in dependence on velocity are investigated and compared to the geometric cross sections and the experiment. The clusters are warmer than the expanding gas because of the time scale of relaxation processes. We also suggest that their translational and rotational kinetic energies are modified due to evaporative cooling. The pickup cross sections determined for the final clusters using molecules of the same kind increase with decreasing velocity, still obeying the (a + b N 1 / 3 ) 2 law. [ABSTRACT FROM AUTHOR]

In this work, we investigate the water capture process for functionalized carbon nanocones (CNCs) through molecular dynamic simulations in the following three scenarios: a single CNC in contact with a reservoir containing liquid water, a single CNC in contact with a water vapor reservoir, and a combination of more than one CNC in contact with vapor. We found that water flows through the nanocones when in contact with the liquid reservoir if the nanocone tip presents hydrophilic functionalization. In contact with steam, we observed the formation of droplets at the base of the nanocone only when hydrophilic functionalization is present. Then, water flows through in a linear manner, a process that is more efficient than that in the liquid reservoir regime. The scalability of the process is tested by analyzing the water flow through more than one nanocone. The results suggest that the distance between the nanocones is a fundamental ingredient for the efficiency of water harvesting. [ABSTRACT FROM AUTHOR]

The interaction of 2-propanol with Co3O4(001) was studied by vibrational sum frequency spectroscopy and ab initio molecular dynamics simulations of 2-propanol dissolved in a water film to gain an insight, at the molecular level, into the pathways of catalytic oxidation. The experimental study has been performed under near ambient conditions, where the presence of water vapor is unavoidable, resulting in a water film on the sample and, thereby, allowing us to mimic the solution–water interface. Both experiment and theory conclude that 2-propanol adsorbs molecularly. The lack of dissociation is attributed to the adsorption geometry of 2-propanol in which the O–H bond does not point toward the surface. Furthermore, the copresent water not only competitively adsorbs on the surface but also inhibits 2-propanol deprotonation. The calculations reveal that the presence of water deactivates the lattice oxygen, thereby reducing the surface activity. This finding sheds light on the multifaceted role of water at the interface for the electrochemical oxidation of 2-propanol in aqueous solution as recently reported [Falk et al., ChemCatChem 13, 2942–2951 (2021)]. At higher temperatures, 2-propanol remains molecularly adsorbed on Co3O4(001) until it desorbs with increasing surface temperature. [ABSTRACT FROM AUTHOR]

The humidity stability and phase transition mechanism of the all-inorganic perovskite CsPbI2Br based on an optimized dual-source co-evaporation preparation process are investigated at the film interface level. It is found that the CsPbI2Br films annealed at 300 °C for several minutes exhibit a best crystallinity and photoelectric properties. The as-grown CsPbI2Br film is confirmed to be a α phase with a dark brown cubic crystal structure and an average visible transparency of 35.9%. But it will be transformed into its δ phase with a transparent orthorhombic crystal structure and an average visible transparency of 80.3% after a certain amount of moisture exposure. Compared with the α phase film, the electronic structure of the δ phase has also changed significantly with a VBM shift of about 0.32 eV to high binding energy. The results of AR-XPS show that the water molecules in perovskite CsPbI2Br after a moisture exposure only adsorb on the surface rather than penetrate the interior of the lattice. When water molecules adsorb on the lattice surface, halide ions should migrate towards the lattice surface due to their high hydration enthalpy, resulting in halide vacancies within the lattice and causing the reduction of energy barrier for phase transition from α phase to δ phase. So the CsPbI2Br film will transform from its α phase to δ phase induced by water vapor, and this phase transition will be reversed to some extent after another annealing. [ABSTRACT FROM AUTHOR]

Both, aluminum doped zinc oxide (AZO) and vertically aligned carbon nanotubes (VACNT) have outstanding properties and promising applications in the future, however, there is little information in the scientific literature on whether this is feasible. In this study, we investigated the effects of catalyst layer deposition parameters and the synthesis parameters by using a simple and cost-effective dip coating method to form alumina support layer and iron and cobalt bimetal catalyst layer on the AZO surface thereafter performing synthesis via catalytic chemical vapor deposition technique at 650 °C. In order to gain useful information about the structure of the VACNTs, several parameters were varied during both catalyst layer preparation (e.g. catalyst ink concentration) and CCVD synthesis (e.g. water vapor gas feed, the presence of hydrogen gas). The resulting samples were investigated by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results indicated that the length and structure of CNTs were strongly affected by the catalyst ink concentration and water vapor. [ABSTRACT FROM AUTHOR]

Cotton is well adapted to dry areas, but progressive water deficits can lead to declines in net photosynthesis (A), ultimately reducing yield. However, the exact mechanism responsible for this decline in net photosynthesis (stomatal or non‐stomatal) is not fully understood under field conditions, partially due to limitations in the ability to collect critical data. To our knowledge, no other study has compared the drought responses of Pima and upland cotton using both CO2 response and chlorophyll fluorescence under field conditions. To this end, a field study was conducted to quantify the impact of progressive mild drought, as measured by midday stomatal conductance to water vapour (gs), on cotton leaf metabolism in Pima and upland cotton. Survey gas exchange and rapid photosynthetic CO2 response (RACiR) were conducted during flowering on the same leaf. The study observed decline in A as gs declined for both species. Correlation analysis indicated typical relationships with A and parameters associated with stomatal limitations such as decreased CO2 inside the leaf and at the site of carboxylation; however, it was found that while Pima exhibited a strong relationship between maximum electron transport rate (Jmax) and electron transport rate (ETR), upland cotton did not. Furthermore, when ETR is broken down into proportions contributing to net photosynthesis and photorespiration (ETRA, ETRP, respectively), we found that a greater proportion of ETR is being shuttled to the photorespiratory pathway in upland, relative to Pima as gs decreases. Our results fill critical knowledge gaps that can be useful for modellers and breeders when preparing for future climate change scenarios. [ABSTRACT FROM AUTHOR]

Terrestrial planets currently in the habitable zone around M dwarfs are estimated to have been in runaway greenhouse conditions for up to ∼1 Gyr due to the long-term pre-main-sequence phase of M dwarfs. These planets likely lose a significant portion of water during the pre-main-sequence phase owing to H2O photolysis followed by hydrogen and oxygen loss to space. However, the effects of H2O reproduction reactions and UV shielding by chemical products that reduce photolysis-induced water loss have yet to be estimated. Here, we apply a 1D photochemical model to a H2O-dominated atmosphere of an Earth-like planet around a pre-main-sequence M dwarf to estimate these effects. We find that water loss is suppressed by efficient H2O reproduction reactions and by UV shielding due to O2. The water loss rate decreases by several to several hundred times compared to that in previous studies, with the assumption that the water loss rate is limited by stellar X-ray and extreme-ultraviolet flux or hydrogen diffusion through the atmosphere. Our results imply that terrestrial planets currently in the habitable zone around M dwarfs are more likely to retain surface water than previously estimated. [ABSTRACT FROM AUTHOR]

Summary: This study investigated the effectiveness of a composite film made of cornstarch (CS) and chlorophyllin (Chl) in preserving wrapped and irradiated shrimp for 5 days at 4 °C. The study found that adding Chl powder increased moisture content, water solubility, water vapour permeability and water contact angle but reduced thermal stability and crystallinity. Notably, higher Chl concentration caused rougher surface and looser structure, while lower concentration resulted in better dispersion. Moreover, increased Chl concentration and longer irradiation time led to higher singlet oxygen production, while hydroxide radical and hydrogen peroxide production peaked at 30.57 and 1.92 μg g−1 respectively. Shrimps wrapped in 5% Chl‐incorporated CS films presented acceptable levels of nitrogen and bacterial count for up to 4 days. Hence, the study suggests that Chl powder inclusion in CS films could be a viable preservation method in the food packaging industry, especially when combined with photodynamic therapy. [ABSTRACT FROM AUTHOR]

In this article, an experiment has been carried out with heat pipe vacuum or evacuated tube collector to produce water from atmospheric air. In this experiment, the regeneration and adsorption method has been adopted, that is, water has been produced through the adsorption and regeneration of desiccants. The desiccant is heated through a hot surface to facilitate its regeneration. Limited experiments have been conducted to obtain water through the regeneration of desiccant using a hot surface. For the condensation of water vapor, a novel box has been designed, named the "novel‐designed acrylic box." The water is collected in a measuring flask or beaker to determine its quantity. Silica gel desiccant has been used for the adsorption and regeneration of water vapors. In this experiment, the adsorption process for silica gel was carried out in two different ways. In the first method, 1 kg of silica gel was scattered on the copper tray, that is, inside the system, while in the second method, 1 kg of silica gel was scattered on the paper, that is, outside of the system. In the first case silica gel adsorbed 137 g water vapor, and in the second case, it adsorbed 232 g water vapor. In the first case of adsorption, 70 mL water was produced while in the second case of adsorption, 175 mL water was produced from ambient air. The system's maximum efficiency was found to be 4.9%. Effects of various parameters, such as solar intensity, ambient temperature, wind speed, and so forth, have been studied. [ABSTRACT FROM AUTHOR]

Along with regular position-related applications, observations from navigation satellite constellations can also be utilised for atmospheric studies. The present study deals with the 3D water vapour tomography carried out for the first time using Indian GPS stations set up in the Himalayan region. A voxel-based approach is applied to retrieve the vertical profile of precipitable water vapour (PWV). Horizontal 4×4 grids have been formed between 29°–31° latitude and 77.5°–79.5° longitude with 0.5° spatial resolution. To construct a tomography model, voxels are formed over these grids up to 10 km with 0.5 km vertical resolution. Water vapour density (WVD) is estimated for different days to observe its variations under different atmospheric conditions. The results show that the estimated vertical variation of water vapour closely matches the AIRS WVD profile. To compare the results, AIRS WVD observations are interpolated at the same altitude where the tomographic estimations are available. The average root mean square (RMS) error, standard deviation (SD), and mean absolute error (MAE) between estimated water vapour density and AIRS WVD are observed to be 1.52, 1.32 and 2.02 g/m3, respectively. The coefficient of determination (R2) value is observed to be close to 0.9, reflecting an excellent linearity between estimated and observed values. The results also show that the WVD is high up to the 5 km voxel and it is between 0 and 5 g/m3 above 5 km altitude. A good estimation of vertical water vapour profile has been obtained using CORS observations and can be used for further atmospheric analyses in this region. [ABSTRACT FROM AUTHOR]

Facade-rendering mortars and their painting layers are constantly exposed to weather and, therefore, influence the hygrothermal behavior of buildings. The characterization and assessment of coating materials is fundamental, seeking adequacy in their selection, especially regarding moisture and temperature. Considering the exposure conditions of the facades, risks of damages, such as mold development, may be avoided by an assertive evaluation and selection among different types of paints. In this context, this paper experimentally determined essential properties related to the hygrothermal behavior of painted mortars and simulated their resulting performance when applied on exposed facades in three Brazilian cities in distinct bioclimatic zones. Hygrothermal simulations were carried out using the software WUFI Pro 6.6. Six different types of paints were studied, among which satin acrylic paint (SAP) led to the lowest water vapor permeability and matte polyvinyl acetate (PVA), silicate (SIL), lime (LP), and hydrated lime with white glue (HLG) paints led to the highest. Matte acrylic paint (MAP), PVA, SIL, LP, and HLG had similar impacts on the vapor transmission of mortar renderings. In the simulations, reference (REF) and LP specimens generally resulted in the highest water contents throughout the year, followed by SIL and HLG. SAP led to the lowest water content and a more homogeneous curve than the other paints. Among the studied cities, Macapá, which has the highest annual normal rainfall sum and mean relative humidity, also had the highest mean total water content values over time, followed by Porto Alegre and Petrolina. In general, no probable mold development is expected. However, caution should be taken when extrapolating the results for climate or construction conditions different than the simulated ones. [ABSTRACT FROM AUTHOR]

Three types of smectite with various crystallochemical compositions and interlayer cations as well as kaolinite and illite were fired at 800°C and 650°C and tested for their rehydroxylation's (RHX) potential and kinetics in the presence of water vapor at 200°C–350°C. A dehydroxylated structure of 2:1 Al‐rich mineral with the interlayer pillared by a large cation (like K+ or Cs+) is wide enough to allow H2O diffusion which results in advanced RHX, that is, restoring up to several tens of percent of the original OH content. Such 2:1 layer structures (beidellite, illite) do not follow the time‐to‐the‐quarter (TTTQ) kinetics during RHX and show a non‐Arrhenius behavior for isothermal RHX. Because TTTQ kinetics is assumed in an RHX dating of ceramic artifacts in archaeometry, fired‐clay ceramics prepared from material dominated by Al‐rich 2:1 minerals was found unfeasible for RHX dating. Kaolinite and Mg2+‐ or Ca2+‐exchanged smectites show the Arrhenius behavior and follow the TTTQ kinetics of RHX, resulting in apparent Ea increase with the progress of reaction (up to α ∼0.2) of ∼20–50 kJ/mol in beidellite and 15–35 kJ/mol in montmorillonite. We suggest using 'hydroxylation' rather than 'rehydroxylation' for structurally‐disordered fired clays gaining OH groups in an unknown position. [ABSTRACT FROM AUTHOR]

YbTaO 4 -Ta 2 O 5 composites were designed and different multi-layered YbTaO 4 -Ta 2 O 5 /Yb 2 Si 2 O 7 /Si (YbT-T/YbDS/Si) as well as YbTaO 4 -Ta 2 O 5 /Si (YbT-T/Si) environmental barrier coatings (EBCs) were put forward to protect SiC fiber reinforced silicon carbide (SiC f /SiC) ceramic matrix composites (CMCs). The thermal cycling and the water-vapor/oxygen corrosion behavior of different multi-layered EBCs were compared. Results indicated that the thermal cycling lifetime of the bi-layered YbT-T/Si EBCs was similar with the tri-layered YbT-T/YbDS/Si ones. The ultimate failure of these two EBCs was induced by the cracking of the SiC f /SiC substrates as well as the vertical cracks associated with the thermal mismatch stress among different layers. However, the tri-layered EBCs exhibited greater resistance to water-vapor/oxygen corrosion than the bi-layered ones, primarily due to that the tri-layered YbT-T/YbDS/Si EBCs contained significantly less cracks than the bi-layered ones, limiting the transport of reactant (oxygen and/or water vapor) to reach Si bond coat. [ABSTRACT FROM AUTHOR]

Isotopic ratios in water vapour carry important information about the water reservoir on Mars. Localized variations in these ratios can inform us about the water cycle and surface–atmosphere exchanges. On the other hand, the global isotopic composition of the atmosphere carries the imprints of the long-term fractionation, providing crucial information about the early water reservoir and its evolution throughout history. Here, we report the analysis of measurements of the D/H and 18O/16O isotopic ratios in water vapour in different seasons (L S = 15○, 127○, 272○, and 305○) made with the Echelon-Cross-Echelle Spectrograph (EXES) aboard the Stratospheric Observatory for Infrared Astronomy (SOFIA). These measurements, free of telluric absorption, provide a unique tool for constraining the global isotopic composition of Martian water vapour. We find the maximum planetary D/H ratio in our observations during the northern summer (D/H = 5.2 ± 0.2 with respect to the Vienna Standard Mean Ocean Water, VSMOW) and to exhibit relatively small variations throughout the year (D/H = 5.0 ± 0.2 and 4.3 ± 0.4 VSMOW during the northern winter and spring, respectively), which are to first order consistent though noticeably larger than the expectations from condensation-induced fractionation. Our measurements reveal the annually averaged isotopic composition of water vapour to be consistent with D/H = 5.0 ± 0.2 and 18O/16O = 1.09 ± 0.08 VSMOW. In addition, based on a comparison between the SOFIA/EXES measurements and the predictions from a Global Climate Model, we estimate the D/H in the northern polar ice cap to be |$\sim\!{5}~{{\ \rm per\ cent}}$| larger than that in the atmospheric reservoir (D/Hice = 5.3 ± 0.3 VSMOW). [ABSTRACT FROM AUTHOR]

Commercial GNSS RO products are being touted for their coverage in polar regions where COSMIC-2 observations don't reach. This study seeks to explore their value for Arctic PBL investigations where sufficient lower atmospheric penetration of GNSS RO is vital for representing the persistently shallow PBL. Both NASA purchased commercial RO products, Spire and GeoOptics, have improved lower tropospheric penetration probability over the Arctic Ocean compared to MetOp observations, with Spire having greater volume of observations (nearly two orders of magnitude) compared to GeoOptics. A seasonal cycle is evident in the RO penetration probability (except for Spire) that is found to be related to the water vapor pressure. For winter months, at the 500 m level, which is the standard cut-off threshold used for GNSS RO PBL studies, both products yield a penetration probability of ~80 % of total observations over the Arctic Ocean and up to ~100 % over the frozen sea ice region. As a result, both products are able to sufficiently represent the shallow Arctic PBLH (less than 300 m depth) which is comparable to the PBLH from MERRA-2 reanalysis, unlike MetOp observations which fails to capture PBL heights below 400 m. [ABSTRACT FROM AUTHOR]

As the construction of hydrogen stations and other hydrogen-related facilities progresses, it becomes increasingly crucial for safety designs to account for scenarios where leaked hydrogen might ignite. Since a hydrogen flame is usually invisible, detection must rely on radiative heat or temperature. While it is possible to predict accurate radiative heat flux from a high pressure hydrogen jet flame through detailed numerical calculations of hydrogen combustion with its radiation, the objective of this study is to provide a simpler and more accurate prediction method. Previous experimental data of radiative heat flux, Q r from high pressure hydrogen jet flames were compiled, and a simple experimental equation Q r = 1463.3 (L o / L f) − 2.32 was derived, where L f and L o represent the flame length and the distance perpendicular to the flame axis from the midpoint of the flame length to the observer, respectively. Radiative heat fluxes were computed through detailed numerical simulations using three types of water vapor radiation models: Goody's narrow random band model, the exponential broad band model by Edward and Elsasser's narrow regular band model. The temperature and water vapor partial pressure distributions obtained from numerical simulations were used as input conditions. The results were found to be in good agreement with the experimental equation. Moreover, a simple diagram representing the radiative heat flux from a hydrogen flame was derived using the method of cylinder-like approximation. The results of this study show that if the hydrogen pressure and leakage aperture diameter are given, the radiative heat flux at a certain distance can be predicted with high accuracy. Additionally, the average value of emissivity for the hydrogen diffusion flame was found to be on the order of 0.03. • Experimental data of radiative heat from hydrogen flame. • Wide range of hydrogen release conditions of Pressure 0.5–82 MPa, aperture 0.2–10 mm. [ABSTRACT FROM AUTHOR]

Many plant materials in nature have the ability to change their shape to respond to external stimuli, such as humidity or moisture, to ensure their survival or safe seed release. A well-known example for this phenomenon is the pinecone, which is able to open its scales at low humidity due to the specific bilayer structures of the scale. Inspired by this, we developed a novel humidity-driven actuator based on paper. This was realized by the lamination of untreated paper made from eucalyptus fibers to a paper–carboxymethyl cellulose (CMC) composite. As observed, the hygroexpansion of the composite can be easily controlled by the amount of CMC in the impregnated paper sheet, which, thus, controls the morphologic deformation of the paper bilayer. For a more detailed understanding of these novel paper soft robots, we also studied the dynamic water vapor adsorption, polymer distribution and hygroexpansion of the paper–polymer composites. Finally, we applied a geometrically nonlinear finite element model to predict the bending behavior of paper bilayers and compared the results to experimental data. From this, we conclude that due to the complexity of structure of the paper composite, a universal prediction of the hygromorphic behavior is not a trivial matter. [ABSTRACT FROM AUTHOR]

Traditional fossil energy sources still dominate the world energy structure. And fully utilizing biomass is a viable approach for energy transition. A bubbling fluidized bed has better heat and mass transfer, while particle agglomeration limits the development of its industrial application. In this paper, two-phase flow characteristics of a bubbling fluidized bed are investigated by combining numerical simulations and fluidized bed gasification experiments. Numerical simulations found that the bed fluidization height reached twice the initial fluidization height at the 0.054 m initial fluidization height with uniform particle distribution. Fluidized bed gasification experiments found that syngas yield increased with increasing temperature. The carbon conversion efficiency reached 79.3% and the effective gas production was 0.64 m3/kg at 850 °C. In addition, when the water vapor concentration reached 15%, the carbon conversion efficiency and effective gas production reached the maximum values of 86.01% and 0.81 m3/kg, respectively. [ABSTRACT FROM AUTHOR]

The GaoFen (GF)-5-02 satellite is one of the new generations of hyperspectral observation satellites launched by China in 2021. The directional polarimetric camera (DPC) is an optical sensor onboard the GF-5-02 satellite. The precipitable water vapor (PWV) is a key detection parameter of DPC. However, the existing PWV data developed using DPC data have significant errors due to the lack of the timely calibration of the two bands (865, 910 nm) of DPC used for PWV retrieval. In order to acquire DPC PWV data with smaller errors, a calibration method is developed for these two bands. The method consists of two parts: (1) calibrate the 865 nm band of the DPC using the cross-calibration method, (2) calibrate the 910 nm band of the DPC according to the calibrated 865 nm band of the DPC. This method effectively addresses the issue of the absence of a calibration method for the water vapor absorption band (910 nm) of the DPC. Regardless of whether AERONET PWV data or SuomiNET PWV data are used as the reference data, the accuracy of the DPC PWV data developed using calibrated DPC data is significantly superior to that of the DPC PWV data retrieved using data before recalibration. This means that the calibration method for the NIR bands of the DPC can effectively enhance the quality of DPC PWV data. [ABSTRACT FROM AUTHOR]

Using CloudSat/CALIPSO satellite data and ERA5 reanalysis data from 2006 to 2010, the effects of aerosols on ice- and mixed-phase, single-layer, non-precipitating clouds over the Tibetan Plateau during nighttime in the MAM (March to May), JJA (June to August), SON (September to November), and DJF (December to February) seasons were examined. The results indicated the following: (1) The macrophysical and microphysical characteristics of ice- and mixed-phase clouds exhibit a nonlinear trend with increasing aerosol optical depth (AOD). When the logarithm of AOD (lnAOD) was ≤−4.0, with increasing AOD during MAM and JJA nights, the cloud thickness and ice particle effective radius of ice-phase clouds and mixed-phase clouds, the ice water path and ice particle number concentration of ice-phase clouds, and the liquid water path and cloud fraction of mixed-phase clouds all decreased; during SON and DJF nights, the cloud thickness of ice-phase clouds, cloud top height, liquid droplet number concentration, and liquid water path of mixed-phase clouds all decreased. When the lnAOD was >−4.0, with increasing AOD during MAM and JJA nights, the cloud top height, cloud base height, cloud fraction, and ice particle number concentration of ice-phase clouds, and the ice water path of mixed-phase clouds all increased; during SON and DJF nights, the cloud fraction of mixed-phase clouds and the ice water path of ice-phase clouds all increased. (2) Under the condition of excluding meteorological factors, including the U-component of wind, V-component of wind, pressure vertical velocity, temperature, and relative humidity at the atmospheric pressure heights near the average cloud top height, within the cloud, and the average cloud base height, as well as precipitable water vapor, convective available potential energy, and surface pressure. During MAM and JJA nights. When the lnAOD was ≤−4.0, an increase in aerosols may have led to a decrease in the thickness of ice and mixed-phase cloud layers, as well as a reduction in cloud water path values. In contrast, when the lnAOD was >−4.0, an increase in aerosols may contribute to elevated cloud base and cloud top heights for ice-phase clouds. During SON and DJF nights, changes in various cloud characteristics may be influenced by both aerosols and meteorological factors. [ABSTRACT FROM AUTHOR]

Binary tropical cyclones (BTCs) typically refer to the coexistence of two tropical cyclones (TCs) within a specific distance range, often resulting in disastrous rainstorms in coastal areas of China. However, the differences in rainfall and underlying causes between BTC-influenced typhoons and general typhoons remain unclear. In this article, the TC closer to the rainfall center in the BTC is referred to as the target typhoon (tTC), while the other is termed the accompanying typhoon (cmp_TC). This study compares and analyzes the rainfall differences and potential causes of tTCs and similar typhoons (sim_TC) with a comparable track but which are unaffected by BTCs from 1981 to 2020. The results show that: (1) On average, tTCs and cmp_TCs experience 18.79% heavier maximum daily rainfall compared to general TCs, with a significantly increased likelihood of rainfall ≥250 mm. (2) Given similar tracks, the average rainfall for tTCs (212.62 mm) is 30.2% heavier than that for sim_TCs (163.30 mm). (3) The analysis of potential impact factors on rainfall (translation speed, intensity, direction change) reveals that sim_TCs move at an average of 21.38 km/h, which is about 19.66% faster than the 17.87 km/h of tTCs, potentially accounting for the observed differences in rainfall. (4) Further investigation into the causes of west–east oriented BTC rainfall in the Northern Fujian (N_Fujian) region suggests that water vapor transport and slowing down of the translation speed are the possible mechanisms of BTC influence. Specifically, 80% of tTCs receive water vapor from the direction of their cmp_TC, and the steering flow for tTC is only 59.88% of that for sim_TC. [ABSTRACT FROM AUTHOR]

High transmittance, high density, and good mechanical properties of silicon nitride (SiNx) make it a potential candidate for barrier layers of flexible organic light emission diodes (FOLEDs). However, the overall characteristics and water oxygen barrier properties of the films are easily affected by the dangling bonds in the films. After adding hydrogen flow rate to the deposition conditions of SiNx films, the hydrogen content interacts with the dangling bonds in amorphous SiNx, which could reduce the number of dangling bonds and improve the density of the hydrogenated amorphous silicon nitride (SiNxHy) films. The high‐density film layer could effectively prevent the invasion of water vapor due to its smaller pinhole density. Therefore, the water oxygen barrier performance of SiNxHy is significantly improved, the maximum decrease in water vapor transmittance rate (WVTR) value is approximately 22.4%. In addition, the increase of hydrogen content also changed the overall properties of the films, including transmittance, elastic modulus, hardness, residual stress, and fracture strain. Therefore, compared with SiNx films, SiNxHy films have more excellent mechanical and optical properties. The SiNxHy films featuring a simplified preparation process with high efficiency, low cost, and superior barrier performance is of great potential for the commercial applications. [ABSTRACT FROM AUTHOR]

During the Water Vapor Lidar Network Assimilation (WaLiNeAs) campaign, 8 lidars specifically designed to measure water vapor mixing ratio (WVMR) profiles were deployed on the western Mediterranean coast. The main objectives were to investigate the water vapor content during case studies of heavy precipitation events in the coastal Western Mediterranean and assess the impact of high spatio-temporal WVMR data on numerical weather prediction forecasts by means of state–of–the–art assimilation techniques. Given the increasing occurrence of extreme events due to climate change, WaLiNeAs is the first program in Europe to provide network–like, simultaneous and continuous water vapor profile measurements. This paper focuses on the WVMR profiling datasets obtained from three of the lidars managed by the French component of the WaLiNeAs team. These lidars were deployed in the towns of Coursan, Grau du Roi and Cannes. This measurement setup enabled monitoring of the water vapor content within the low troposphere along a period of three months over autumn – winter 2022 and four months in summer 2023. The lidars measured the WVMR profiles from the surface up to approximately 6–10 km at night, and 1–2 km during daytime; with a vertical resolution of 100 m and a time sampling between 15 – 30 min, selected to meet the needs of weather forecasting with an uncertainty lower than 0.4 g kg-1. The paper presents details about the instruments, the experimental strategy, as well as the datasets given in NETcdf format. The final dataset is divided in two datasets, the first with a time resolution of 15 min, which contains a total of 26 423 WVMR vertical profiles and the second with a time resolution of 30 min to improve the signal to noise ratio and signal altitude range. [ABSTRACT FROM AUTHOR]

In order to investigate the dynamic process of the heat and mass transfer phenomenon of water vapor on activated carbon, a fixed‐column adsorption unit and two kinds of activated carbon were used as adsorbent for water vapor adsorption under the adsorption temperature 293.15 K, 303.15 K and 313.15 K, respectively. A coupled model was developed by mass and energy balance, mass transfer and simplified DO adsorption equilibrium equation. The effects of physical parameters on heat and mass transfer were theoretically investigated. Results show that the numerical model match well with the experimental data (R2>0.993). The axial diffusion coefficient (DL) increases from 1.226×10−6 m2 s−1 to 4.062×10−6 m2 s−1 for RAC and 1.425×10−6 m2 s−1 to 4.030×10−6 m2 s−1 for MAC, mass transfer coefficient (k) increases from 8.171 s−1 to 27.083 s−1 for RAC and 9.499 s−1 to 26.864 s−1 for MAC. Concurrently, the breakthrough time of adsorption water vapor gradually shorten from 1000 s to 780 s with temperature increasing from 293.15 K to 313.15 K. The effect of axial diffusion coefficient (DL) on mass transfer is not obvious. Furthermore, the influence of the mass transfer coefficient (k) on temperature variation rate surpasses that of the internal heat transfer coefficient (h). [ABSTRACT FROM AUTHOR]

This study developed a kind of PEG-crosslinked O-carboxymethyl chitosan (O-CMC–PEG) with various PEG content for food packaging. The crosslinking agent of isocyanate-terminated PEG was firstly synthesized by a simple condensation reaction between PEG and excess diisocyanate, then the crosslink between O-carboxymethyl chitosan (O-CMC) and crosslinking agent occurred under mild conditions to produce O-CMC–PEG with a crosslinked structure linked by urea bonds. FT-IR and 1H NMR techniques were utilized to confirm the chemical structures of the crosslinking agent and O-CMC–PEGs. Extensive research was conducted to investigate the impact of the PEG content (or crosslinking degree) on the physicochemical characteristics of the casted O-CMC–PEG films. The results illuminated that crosslinking and components compatibility could improve their tensile features and water vapor barrier performance, while high PEG content played the inverse effects due to the microphase separation between PEG and O-CMC segments. The in vitro degradation rate and water sensitivity primarily depended on the crosslinking degree in comparison with the PEG content. Furthermore, caused by the remaining –NH2 groups of O-CMC, the films demonstrated antibacterial activity against Escherichia coli and Staphylococcus aureus. When the PEG content was 6% (medium crosslinking degree), the prepared O-CMC–PEG−6% film possessed optimal tensile features, high water resistance, appropriate degradation rate, low water vapor transmission rate and fine broad-spectrum antibacterial capacity, manifesting a great potential for application in food packaging to extend the shelf life. [ABSTRACT FROM AUTHOR]

Potentially habitable exoplanets are targets of great interest for the James Webb Space Telescope and upcoming mission concepts such as the Habitable Worlds Observatory. Clouds strongly affect climate and habitability, but predicting their properties is difficult. In Global Climate Models (GCMs), especially those aiming at simulating Earth, cloud microphysics is often crudely approximated by assuming that all cloud particles have a single, constant size or a prescribed size distribution and that all clouds in a grid cell are identical. For exoplanets that range over a large phase space of planetary properties, this method could result in large errors. In this work, our goal is to determine how cloud microphysics on terrestrial exoplanets, whose condensable is mainly water vapor, depend on aerosol properties and planetary parameters such as surface pressure, surface gravity, and incident stellar radiation. We use the Community Aerosol and Radiation Model for Atmospheres as a 1D microphysical model to simulate the formation and evolution of clouds including the processes of nucleation, condensation, evaporation, coagulation, and vertical transfer. In these 1D idealized experiments, we find that the parameters that determine the macrophysical thermal structure of the atmospheres, including surface pressure and stellar flux, impact cloud radiative effect (CRE) most significantly. Parameters such as gravity and number density of aerosols working as cloud condensation nuclei affect the microphysical processes of cloud formation, including activation and vertical transfer. They also have a significant, though weaker effect on CRE. This work motivates the development of more accurate GCM cloud schemes and should aid in the interpretation of future observations. [ABSTRACT FROM AUTHOR]

Carbonation resistance ability is one of the most important durability-related proprieties of cement-based materials. Through the carbonation depth experiment, isothermal conduction calorimetry, XRD, BET, and water vapor sorption, the effect of calcium nitrite (Ca(NO3)2) on the carbonation properties of cement-based materials is obtained. The result indicates that the addition of Ca(NO3)2 improves the carbonation resistance property of cement-based materials if the hydration of cement pastes and microstructure is modified earlier without affecting the late hydration process. In addition, the refined pores and higher tortuosity cut down the channels, thereby impeding the ingress of carbon dioxide gas into cementitious materials, as confirmed by BET and water vapor sorption. The Ca(NO3)2 exhibits high performance in improving the carbonation resistance and extending the life of strengthened concrete. [ABSTRACT FROM AUTHOR]

In this work, the Y 3 Al 5 O 12 (YAG) coatings prepared by atmospheric plasma spraying were found to have a thermal expansion coefficient of 8.51 × 10-6K-1 from 473 to 1673K and a thermal conductivity of 2.41 W/(m∙K) at 1273K as well as a Young's modulus of 89.4 ± 9 GPa and an average hardness of 6.79 ± 0.24 GPa. Their excellent mechanical and thermal-physical properties have promoted them as thermal/environmental barrier coating (T/EBC) materials. Multi-layered Y 3 Al 5 O 12 /Yb 2 SiO 5 /Yb 2 Si 2 O 7 (YAG/YbMS/YbDS) T/EBCs were deposited on SiC based substrate. Thermal cycling and water vapor corrosion behavior of the YAG/YbMS/YbDS T/EBCs were also investigated. The cyclic oxidation tests at 1573K showed that the coatings had excellent resistance to thermal cycling, with an average lifetime of 442 ± 10 cycles. The initial oxidation of the Si layer at the edge, resulting in the formation of a 4.8 μm thick thermally grown oxide (TGO), coupled with the volumetric changes and the associated phase transformation stress, led to the delamination of the coatings from the edges. Due to the very low oxygen diffusion rate of YAG layer, the thickness of TGO was only 1.2 μm after steam corrosion for 40 h. The amorphous crystallization as well as thermal mismatch stresses were the main reasons for the coating failure. [ABSTRACT FROM AUTHOR]

Incorporating the nuclear magnetic resonance (NMR) technique, a newly developed infiltration instrument constructed from polytetrafluoroethylene is designed for the rapid determination of unsaturated hydraulic conductivity of bentonite materials. The proposed approach is founded on measuring the variation of the NMR signal in numerous cross sections of the specimen during the infiltration test, enabling the determination of water content distribution. Through integration with the instantaneous profile method, unsaturated hydraulic conductivity can be obtained using Darcy's law. The mechanism underlying the observed U-shaped trend of unsaturated hydraulic coefficient with decreasing suction can be attributed to the relatively high value controlled by water vapor diffusion at higher suction stages, as well as the hydraulic conductivity increasing near saturation, similar to the behavior of most unsaturated soils. The consistency of test results with those acquired from conventional measurements, regarding amplitude level and evolutionary pattern, provides evidence of the reliability of the proposed method. The primary improvement lies in the real-time acquisition of the water content profile using the spatial encoding technique in the NMR in the infiltration test. Simultaneously, the approach substantially reduces the test duration from thousands of hours to dozens of hours while maintaining measurement accuracy. [ABSTRACT FROM AUTHOR]

Saturation characteristics of water and capillary pressure are important for hydrofracturing or water flooding, which is widely adopted in dust suppression, methane displacement, and gas and coal outburst elimination. In this paper, we have studied the water saturation characteristics of coal samples with different coal ranks and their effect on capillary pressure. It was found that the isothermal adsorption of water vapor from coal samples can be divided into three processes: monolayer adsorption, multilayer adsorption, and capillary condensation. The dent isothermal adsorption model can well describe water vapor adsorption of coal samples, indicating water molecules were first adsorbed on the first‐order adsorption site of pore surfaces at low relative humidity and then on the second‐order adsorption site with increasing relative humidity. An obvious hysteresis occurred in the process of water imbibition and drainage. A capillary pressure of ~325 MPa or even larger was required to displace the water from the coal. Besides, micro‐ and mesopores play a more important role in capillary pressure. The capillary pressure of coal samples was positively correlated with wettability at lower water saturation, but it is not significant at higher capillary pressures. Therefore, the article's results provide a new direction for solving the water‐locking effect in coal seams. [ABSTRACT FROM AUTHOR]

Using biodegradable films as a substitute for conventional polyolefin films has emerged as a crucial technology to combat agricultural white pollution. To address the shortcomings in the tensile strength, water vapor barrier properties, and degradation period of PBAT-based biodegradable films, this investigation aimed to create a composite film that could improve the diverse properties of PBAT films. To achieve this, a PBAT/PLA-PPC-PTLA ternary blend system was introduced in the study. The system effectively fused PBAT with PLA and PPC, as evidenced by electron microscopy tests showing no apparent defects on the surface and cross-section of the blended film. The developed ternary blend system resulted in a 58.62% improvement in tensile strength, a 70.33% enhancement in water vapor barrier properties, and a 30-day extension of the functional period compared to pure PBAT biodegradable films. Field experiments on corn crops demonstrated that the modified biodegradable film is more suitable for agricultural production, as it improved thermal insulation and moisture retention, leading to a 5.45% increase in corn yield, approaching the yield of traditional polyolefin films. [ABSTRACT FROM AUTHOR]

In the summer of 2022, Pakistan experienced a severe flood event that brought great destruction to the local people and ecosystem. However, there is no comprehensive study on the process, spread and causes of this flood. Therefore, we combined multiple satellite gravity data, meteorological data, hydrological data, and satellite remote sensing data to conduct a thorough investigation and study of this flood. The results show that a 20-year time series of the terrestrial water storage change based multiple gravity data has the high accuracy and reliability, which is used for detecting the flood. The flood propagated through meteorological system (three months), agricultural system (six months) and terrestrial ecosystems (five months), respectively, and the two southern provinces (Balochistan and Sindh) are the most affected by the flood, whose flood severity is 6.955 and 9.557, respectively. The center of the severe flood is located at the border region between the above two province. The severe flood is attributed primarily to the global extreme climate events (La Niña and negative Indian Ocean Dipole events) that altered the transport path of water vapor in the Indian Ocean, causing large amounts of water vapor to converge over Pakistan, resulting in heavy precipitation, and secondarily to the melting of extensive glacier in the mountainous of northern Pakistan as a result of the high temperature in March-May 2022. The above results contribute to the understanding of the mechanism of the impact of extreme climate events on the regional climate, and provide some references for the study of severe floods. [ABSTRACT FROM AUTHOR]

Polar mesospheric cloud (PMC) data obtained from the Aeronomy of Ice in the Mesosphere (AIM)/Cloud Imaging and Particle Size (CIPS) experiment and Himawari-8/Advanced Himawari Imager (AHI) observations are analyzed for multi-year climatology and interannual variations. Linkages between PMCs, mesospheric temperature, and water vapor (H2O) are further investigated with data from the Microwave Limb Sounder (MLS). Our analysis shows that PMC onset date and occurrence rate are strongly dependent on the atmospheric environment, i.e., the underlying seasonal behavior of temperature and water vapor. Upper-mesospheric dehydration by PMCs is evident in the MLS water vapor observations. The spatial patterns of the depleted water vapor correspond to the PMC occurrence region over the Arctic and Antarctic during the days after the summer solstice. The year-to-year variabilities in PMC occurrence rates and onset dates are highly correlated with mesospheric temperature and H2O. They show quasi-quadrennial oscillation (QQO) with 4–5-year periods, particularly in the southern hemisphere (SH). The combined influence of mesospheric cooling and the mesospheric H2O increase provides favorable conditions for PMC formation. The global increase in mesospheric H2O during the last decade may explain the increased PMC occurrence in the northern hemisphere (NH). Although mesospheric temperature and H2O exhibit a strong 11-year variation, little solar cycle signatures are found in the PMC occurrence during 2007–2021. [ABSTRACT FROM AUTHOR]

Studies have demonstrated the potential of satellite thermal infrared observations to detect anomalous signals preceding large earthquakes. However, the lack of well-defined precursory characteristics and inherent complexity and stochasticity of the seismicity continue to impede robust earthquake forecasts. This study investigates the potential of pre-seismic thermal anomalies, derived from five satellite-based geophysical parameters, i.e., skin temperature, air temperature, total integrated column water vapor burden, outgoing longwave radiation (OLR), and clear-sky OLR, as valuable indicators for global earthquake forecasts. We employed a spatially self-adaptive multiparametric anomaly identification scheme to refine these anomalies, and then estimated the posterior probability of an earthquake occurrence given observed anomalies within a Bayesian framework. Our findings reveal a promising link between thermal signatures and global seismicity, with elevated forecast probabilities exceeding 0.1 and significant probability gains in some strong earthquake-prone regions. A time series analysis indicates probability stabilization after approximately six years. While no single parameter consistently dominates, each contributes precursory information, suggesting a promising avenue for a multi-parametric approach. Furthermore, novel anomaly indices incorporating probabilistic information significantly reduce false alarms and improve anomaly recognition. Despite remaining challenges in developing dynamic short-term probabilities, rigorously testing detection algorithms, and improving ensemble forecast strategies, this study provides compelling evidence for the potential of thermal anomalies to play a key role in global earthquake forecasts. The ability to reliably estimate earthquake forecast probabilities, given the ever-present threat of destructive earthquakes, holds considerable societal and ecological importance for mitigating earthquake risk and improving preparedness strategies. [ABSTRACT FROM AUTHOR]

Thermal conductivity sensors face an omnipresent cross-influence through varying humidity levels in real-life applications. We present the results of investigations on the influence of humidity on a hydrogen thermal conductivity sensor and approaches for predicting the behavior of thermal conductivity towards humidity. A literature search and comparison of different mixing equations for binary gas mixtures were carried out. The theoretical results were compared with experimental results from three different thermal conductivity sensors with mixtures of water vapor in nitrogen. The mixing equations show a large discrepancy between each other. Some of the models predict a continuously decreasing thermal conductivity and some predict an increasing thermal conductivity for increasing levels of humidity. Our measurements indicate an increase in thermal conductivity followed by a decrease after reaching a peak value. It is shown that the measured behavior is reproducible with different sensors. Depending on the sensor, this corresponds to an error up to 2 vol.% in the measured hydrogen value. The measured behavior is consistent with only one of the three models. Compared to this model, our own sensor shows a maximum deviation of 1.4%. Mixing equations for gas mixtures must be chosen carefully, taking into consideration whether mixing partners include polar or non-polar molecules. Some simplified mixing equations cannot be used to calculate the thermal conductivity of water vapor in air or nitrogen. [ABSTRACT FROM AUTHOR]

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging. [ABSTRACT FROM AUTHOR]

Many segmentation or change‐point detection methods for homogenizing climate time series compare candidate station data with reference data to eliminate common climate signals and more efficiently detect spurious, non‐climatic changes. One drawback is that it is difficult to decide whether the detected change‐point is due to the candidate series or to the reference. A so‐called attribution procedure is typically applied in a post‐processing step for each detected change‐point. This article describes a new statistical method for the attribution of change‐points detected in Global Navigation Satellite System (GNSS) minus reanalysis series of integrated water vapour. It requires at least one nearby station with similar GNSS and reanalysis data. Six series of differences are formed from the four base series (BS) and are tested for a significant jump at the time of the change‐point detected in the candidate station. The six test results are analysed with a statistical predictive rule to attribute the change‐point to one, or several, of the four BS. Original aspects of our method are: (1) the significance test, which is based on a generalized linear regression approach, taking both heteroscedasticity and autocorrelation into account; (2) the predictive rule, which uses a machine learning method and is constructed from the test results obtained with the real data by using a resampling strategy. Four popular machine learning methods have been compared using cross‐validation and the best one was applied to a real data set (49 main stations with 114 change‐points). The results depend on the choice of the test significance level and the aggregation method combining the prediction results when several nearby stations are available. We find that 62% of the change‐points are attributed to GNSS, 19% to the reanalysis, and 10% are due to coincident detections. [ABSTRACT FROM AUTHOR]

Water vapour is a critical component of the hydrological cycle and plays a key role in climate systems and water resources on the Tibetan Plateau (TP). However, the effect of water vapour on extreme precipitation during the snow season over the TP, where snow cover is widespread, has not been determined. In this study, we investigated the water vapour contributions from extreme precipitation events during the snow season from 1980 to 2017 in four subregions of the TP using the flexible particle dispersion method. We divided the TP into four regions: the northeastern TP (NETP), northwestern TP (NWTP), southeastern TP (SETP) and southwestern TP (SWTP). The water vapour contributions from extreme precipitation among the four subregions were clearly different. The most important water vapour area that contributed the most water vapour to extreme precipitation over the NETP was from local contributions; nevertheless, Central Asia contributed the most water vapour to the NWTP. Water vapour from the Arabian Sea and Bay of Bengal (ASBB) dominantly controlled extreme precipitation in the SETP at a ratio of 45% and in the SWTP at a ratio of 72.9%. The water vapour contribution from the ASBB was significantly correlated with the extreme precipitation occurring in the TP subregions during the snow season in comparison to that of non‐extreme precipitation. These results could improve the understanding of water vapour cycle differences across the interior TP; additionally, our study provides a theoretical reference for the relationship between the snow distribution and water vapour sources in the TP. [ABSTRACT FROM AUTHOR]

Atmospheric water vapor is a crucial factor in the Earth's water cycle. As an important greenhouse gas, changes in the spatio‐temporal distribution of atmospheric water vapor can contribute to the occurrence of various extreme weather phenomena. Lidar, with its high spatial and temporal resolutions, has great potential for applications in water vapor profile detection. Raman lidar and differential absorption lidar (DIAL) have been successfully used to detect atmospheric water vapor. System calibration is crucial to ensure that the measured profile accurately represents the concentration profile of atmospheric water vapor. Choosing an effective system calibration method can ensure the accuracy of long‐term lidar measurements. This paper reviews the latest progress and applications of atmospheric water vapor lidar calibration in recent years. The basic principles of Raman lidar and DIAL calibration are introduced. Various methods and benefits of system calibration are discussed. Raman lidar has three commonly used calibration methods: external calibration, internal calibration, and hybrid calibration methods. The most commonly used method is external calibration based on radiosondes. DIAL is usually implemented with an advantageous self‐calibration method. Finally, potential development directions for atmospheric water vapor lidar and calibration technology are discussed. This article is categorized under:Science of Water > MethodsEngineering Water > MethodsHuman Water > Value of Water [ABSTRACT FROM AUTHOR]

This study focuses on the modification of starch using cold plasma (CP) for 0, 30, 60, and 90 seconds. The prepared films are characterized (i.e., thickness, water vapor permeability, intrinsic viscosity, solubility in water, and moisture absorption). The thickness, water vapor permeability (WVP), intrinsic viscosity, solubility in water (SW), moisture absorption (MA), and roughness of the modified starch films increases with longer plasma‐processing time (PPT). Conversely, the contact angle and density of the films decreases. However, there are no significant changes observed in the moisture content and UV–Vis spectrum of the cold plasma‐irradiated starch (CPS) films. The CP treatment has some effects on the mechanical properties of the films, such as elongation at break and tensile energy to break, but the tensile strength remains unaffected by PPT. Additionally, CP has a significant impact on the visual properties of CPS films, with increased lightness and white index with longer PPT. Most of the observed characteristics are attributed to physical changes in the starch structure caused by etching. Overall, CP is considered a green, and easy for modifying starch‐based packaging materials. However, it is not an effective method for reducing the sensitivity of the films to moisture at the applied PPT. [ABSTRACT FROM AUTHOR]

To effectively reduce SO2 emissions, flue gas desulfurization methods are widely used in coal‐fired power plants. In desulfurization, the dry sorbent injection (DSI) technology has the advantages of high desulfurization efficiency, simple operation, convenient adjustment, and low initial investment. Here, a pilot‐scale experimental system was designed and built to investigate the desulfurization characteristics of the DSI technology. The influence of the residence time of the desulfurizer, the reaction temperature, the stoichiometric ratio of the desulfurization reaction, the particle size of the desulfurizer, the inlet SO2 concentration, the dust concentration, and the water vapor content in the flue gas on the desulfurization efficiency at low SO2 concentrations was studied by injecting NaHCO3 into the pipeline. The desulfurization efficiency can be significantly improved by reducing the desulfurizer particle size or increasing the water vapor content in the flue gas at low SO2 concentration. An empirical formula describing the dependence of the desulfurization efficiency on experimental parameters is given. [ABSTRACT FROM AUTHOR]

Casein proteins were cross-linked with dialdehyde tragacanth gum (DTG) to create a film with improved physico-mechanical properties. The DTG/casein film with a 2:1 ratio exhibited good physical and barrier properties, such as tensile strength (TS) (12.92 MPa), water contact angle (WCA) (73.2°), water vapor permeability (WVP) (2.1 × 10 − 10 g·mm/h·mm2·Pa), and water solubility (WS) (22.3%). Carbon dot (CD) nanoparticles were synthesized from milk permeate using a hydrothermal method. CDs (5 to 50% w/w) were incorporated into the optimal cross-linked casein films to create casein-based nanocomposites. Adding CDs (up to 15% w/w) increased the film's tensile strength by 36%. Scanning electron microscopy (SEM) confirmed the homogeneous distribution of 5% CD in the films without aggregation. The hydrophilicity of the films increased with the addition of CDs. Additionally, incorporating CDs significantly reduced UV transmission, with a 99.09% reduction in UV-C and a 97.46% reduction in UV-A. The CD-added nanocomposite films demonstrated potent antioxidant activity, increasing DPPH scavenging from 18.1 to 94% and ABTS scavenging from 16.4 to 89.3%. No cytotoxicity was observed in normal cells (HUVEC) even after 72 h of exposure. Coating butter products with the composite films for 60 days resulted in decreased peroxide value (PV) and thiobarbituric acid reactive substances (TBARS), indicating an oxidation–reduction process. These findings highlight the potential of cross-linked casein films with CDs to extend the shelf life of food products in the food industry. [ABSTRACT FROM AUTHOR]

SiC‐based lining refractories used in incinerators faced serious hot water vapor corrosion. The pores in SiC‐based refractories played a crucial role in corrosion resistance because both the penetration of water vapor and the expulsion of corrosion products depended on diffusion channels provided by pores. The in situ microporous Yb2Si2O7 bonding phase formed in the SiC bricks after sintering at 1550°C under air atmosphere, which simultaneously decreased the apparent porosity and pore size. The optimization of pore structures reduced the permeability to gases of SiC bricks by 37.5%, which prevented the penetration of hot water vapor into SiC bricks. The microporous Yb2Si2O7‐bonded SiC bricks presented only.15% permanent linear change and showed good thermal shock resistance after corrosion at 1000°C for 100 h under hot water vapor atmosphere. Some SiC particles in the refractories could be adopted as high‐temperature pore‐forming agents; the gaseous oxidation products of SiC bricks, including SiO(g) and CO(g), contributed to the generation of microporous Yb2Si2O7 (pore size ≤5 μm) and SiC whiskers during sintering, which obviously improved mechanical properties and water vapor corrosion resistance of SiC bricks. [ABSTRACT FROM AUTHOR]