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This dataset gathers the initial formation and the evolution of water content and distribution, as well as water evacuation, within a lung-inspired PEM (proton exchange membrane) fuel cell with a 50 cm2 active area for various operating conditions such as cell pressure, relative humidity of the reactant (anode and cathode), temperature, and cell current density. Neutron imaging was used since it has been shown to be an effective technique for quantitative analysis of water distribution, obtaining the thickness of the water with the Lambert-Beer law, thus obtaining the numerical data that composes the tables and graphs in this dataset. A series of videos compiling the individual images obtained through neutron imaging, showing the water distribution evolution are presented. Numerical and graphical compilation of the amount of water in a cell through time in different regions of the cell and for a total of 10 experiments are provided. This dataset provides a deeper knowledge on the complex phenomena that liquid water is subjected to in fuel cells along time, as well as a basis for an experimental validation for Computational Fluid Dynamics (CFD) simulations.

High water retention and water capacity of detritus determine its potential hydrological significance in the formation of the water regime of soils and phytoproductivity of forest landscapes. Using computer modeling of water exchange in the soil–plant–atmosphere HYDRUS-1D system, we preliminarily studied the hydrological function of detritus of retention of precipitation water and of root water consumption at different amounts and variants of the arrangement of detritus layers in the soil profile. The soil structures designed on the basis of this information for sustainable afforestation with increased carbon sequestration in field experiments with water balance monitoring demonstrated high efficiency in optimizing soil water retention capacity and water consumption by roots of the test crop (Picea pungens Engelm.) with a two- to threefold reduction in unproductive water losses and a 1.5-to 2-fold increase in the current plant growth relative to untreated control. The physical mechanism of the detritus hydrological function consists in the formation of capillary barriers, blocking evaporation and capillary resorption of soil water due to accumulation at the surface (forest litter) or in layers inside the soil (peat layers in constructozems). [ABSTRACT FROM AUTHOR]

This study presents an experimental comparison of three solar stills operating under identical weather conditions. The first still, designated as the control conventional solar still (CSS), was compared to two modified versions: one featuring plant Cladium mariscus in its green state modified solar still (MSS1) and the other with the same quantity of plant in its dry state. The primary objective was to assess how the presence of plant Cladium mariscus, available abundantly and free of cost in the region, influences the performance of the solar still. The underlying hypothesis was that such integration could enhance water production. The results of the experiments revealed notable improvement rates; with MSS1 achieving a 17.33% enhancement and MSS2 was demonstrating a remarkable 33.27% improvement. In terms of thermal efficiency, MSS1 achieved 28.25%, MSS2 reached 32.65%, while CSS recorded 25.37%. These findings offer valuable insights for the development of more effective strategies to address the challenges associated with drinking water scarcity. [ABSTRACT FROM AUTHOR]

To address safety problems caused by goaf and water accumulation in open-pit mines, the shallow three-dimensional seismic method and transient electromagnetic method were integrated and applied to detect the mining goaf distribution scope and the water accumulation conditions. In view of the special topographic conditions of an ultrashallow layer and high drop in an open-pit mine, we proposed utilizing bin homogenization and multidomain joint denoising to improve the reliability of seismic data. By using seismic-sensitive attributes to predict the goaf, the transient electromagnetic method was employed to further predict the water accumulation in the goaf. The results show that the shallow seismic method could clearly reflect the reflected-wave variation features of the goaf. The features of a junction between a normal seam and goaf vary obviously, and the prediction effect of the goaf boundary with high resolution is in line with the actual situation. Furthermore, taking the goaf scope prediction with the shallow three-dimensional seismic method as a base, targeted transient electromagnetic detection was deployed, with a detailed analysis of the survey-line repeated areas of the shallow seismic and transient electromagnetic methods. Making full use of the advantages of the shallow seismic and transient electromagnetic methods, we propose a reasonable data interpretation method in combination with the special topographic conditions of open-pit mines, which greatly improves the prediction effect of goaf and water accumulation conditions. [ABSTRACT FROM AUTHOR]

When encountering heavy rain, the membrane surface with a relatively small slope is easy to accumulate water. Accurately simulating the deformation of the membrane surface at this time will help ensure the safety of the structure. The linear constitutive model of membrane material used in existing research is not suitable for simulating the deformation of membrane structure in rainstorm. This study conducts a uniform load test on a membrane structure to simulate the mechanical behavior of the membrane surface in rainstorm and obtains the deformation form of the structure when water is accumulated. The linear constitutive model and the double broken line constitutive model of membrane material are used in the finite element model of the membrane structure for load analysis. By comparing the deformation of the finite element model and the actual structure, it selects the constitutive model suitable for simulating the deformation of the membrane structure in heavy rain. The numerical simulation results show that the structural deformation simulated by the double broken line constitutive model is closer to the deformation measured in the experiment than the linear constitutive model. The research results can provide a reference for the selection of the membrane constitutive model and the analysis of membrane structure in rainstorm.

In recent years, with the large-scale and high-intensity mining of coal resources, the problem of water accumulation in mining areas with high groundwater levels has become particularly prominent, which has had a serious impact on the surrounding ecological environment. In order to provide scientific basis for the restoration of the ecological environment, the study on the temporal and spatial evolution characteristics and influencing factors of the coal mining subsidence area with high groundwater level were carried out. Taking the whole mining area of Anhui Province as the research subject, based on Landsat TM/OLI remote sensing data, the NDWI and visual interpretation method were used to conduct surveys on the water accumulation area in the subsidence area from 1995 to 2020 (22 periods ) and 12 months in 2020 (12 periods) and the spatial information of waterlogging in the coal mining subsidence area in Anhui Province in recent 25 years was obtained. Combined with hydrological and rainfall data, the factors affecting the spatio-temporal evolution of waterlogging in the subsidence area were analyzed and discussed. The results show that: ① In the past 25 years, the area of accumulated water in the coal mining subsidence area in Anhui Province has been growing in three stages: slow, fast and stable. During the study period, the average stagnant area increased by about 6 times, from 18.95 km2 to 118.09 km2, with an average annual increase of 3.97 km2. ② From the time scale, the evolution of accumulation area in the subsidence area can be divided into three stages: the first stage (1995—2005), due to the fact that most of the accumulation water has not yet stabilized initially, the growth rate is relatively slow, with an average annual growth rate of 4.65%; In the second stage (2005—2013), based on the rapid growth of coal mining, the area of accumulation water has also entered a period of rapid growth, with an average annual growth rate of 6.64%; In the third stage (2013—2020), the growth rate has begun to decrease, and the accumulation water has gradually stabilized, with an average annual growth rate of 3.42%. From the spatial scale, the accumulation water is mainly concentrated in Huainan and Huaibei cities, accounting for about 70% of the total accumulated water area. ③The long-term factor for the change of the water accumulation is coal mining volume, while the main influencing factor in short time scale is atmospheric rainfall. ④The logistic regression curve was used to establish a prediction model for the water accumulation area of coal mining subsidence in Anhui Province. It is predicted that the coal mining subsidence water area in Anhui Province will still be in a low-speed growth stage in the future. By 2030, the accumulation area in the dry season will reach about 130 km2. The high-precision water accumulation information in the subsidence area was obtained, and its temporal and spatial evolution laws and influencing factors were analyzed, which can provide a scientific basis for the treatment of water accumulation in the coal mining subsidence area with high groundwater level and the ecological restoration of the subsidence area.

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Relative humidity (RH) can be gradually reduced to improve the drying efficiency and quality of materials in hot air drying. The high RH in the early drying stage can rapidly heat up for better diffusion of internal moisture in the material. The internal water can migrate and then spread to the surface of the material. The high RH can reduce the water vapor partial pressure difference between the drying medium and the material surface, in order to inhibit the evaporation rate of water on the surface, and then prevent the surface from drying and crusting. The moisture removal includes two procedures during drying: the internal moisture diffusion to the surface, and the evaporation of surface moisture. Once the surface moisture evaporates too fast, and the internal moisture cannot be supplied to the surface in time, the surface of the material is the first to shrink, which is the direct cause of crust hardening. After the material surface crusts harden, the drying time is prolonged to reduce the rehydration rate and the drying qualities. In the early drying stage, the high RH can improve the internal moisture diffusion rate. Additionally, the surface evaporation rate is reduced. A surface with enough moisture can alleviate the crusting of the material surface for a better drying and rehydration rate. However, it is still lacking in the quantitative comparison of internal moisture diffusion and surface water evaporation. It is also unclear about the process and mechanism of crust formation. Therefore, it is very necessary for the quantitative description of the correlation between the internal moisture diffusion and surface water evaporation on the crusting, in order to optimize the relative humidity for better drying efficiency and quality. In this study, the internal moisture diffusion quality (D), moisture evaporation quality (E), material surface moisture accumulation (Q), material microstructure, and rehydration ratio were investigated under three RH control strategies, including the constant RH (20%, 30%, 40%, and 50%), the RH 50% with different time (10, 30, 60, and 90 min), and the auto RH control strategy using material temperature. The results showed that the D increased gradually with the drying time, and then remained stable under constant RH drying. The E increased gradually with the drying time and then decreased. Specifically, the higher RH was, the faster the material heating rate was, and the larger D was. The lower RH was, the greater E was. When the RH was 20%, 30%, and 40%, the time of Q=0 was 1.11, 1.36, and 1.70 h, respectively. After this time, the material surface presented outstanding crusting. Besides, the higher RH was, the later the time of crusting was. When the RH was 50%, there was no Q<0, indicating no outstanding crusting. When Q>0, the drying rate was consistent with the changing trend of Q value. When Q<0, the corresponding drying rate decreased. When the RH 50% was maintained for 30 min and then reduced to 20%, the time when Q equals 0 was 1.39 h. Compared with the drying condition of RH 20%, the material temperature and internal moisture diffusion rate increased to delay the timing of crust formation. After decreasing the RH, E increased, and the drying time was shortened by 18.5%. Under automatically controlled RH, Q increased rapidly within 0-0.25 h, corresponding to a rapid increase in the drying rate. Q gradually decreased within 0.25-0.50 h. Within 0.78-2.00 h, there were three zeros in Q value, indicating the fluctuation at Q=0. This RH control mode can be expected to serve as the moisture migrating from the inside to the surface evaporate in time without accumulation on the surface. The temperature of the material showed a stepwise upward trend, and then postponed the appearance time of crusting, to retain more water migration channels. In this optimal drying condition, the shortest drying time was 6.1 h, and the highest rehydration ratio was (4.39±0.07) g/g, as well as the lowest shrinkage ratio was 28.55%±1.71%. The automatically controlled RH was the optimal RH controlling drying. This finding can provide a theoretical basis and technical support for the internal migration and surface evaporation of water, particularly for the cause of surface crusting and the optimization of the RH control during drying. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fault process of unit tripping caused by vibration surging of a back pressure unit for heating is introduced. On-site analysis of vibration and eccentricity data showed that there occurred severe collision between rotary and static parts， and the rotor was plastically bended. After uncovering the cylinder， it was found that there were severe collisions between the rotary and static parts of the front steam seal， blade tip and holding ring， and the maximum bending capacity of the rotor was up to 240 μm. Accident analysis shows that the major reasons are ： 1） The rough installation process of the rotor was the hidden danger of the fault； 2） The uneven expansion of cylinder body that caused rotary and static collision during cold start-up and resulted in rotor bending； 3） The leakage steam of shaft seal returned to the cylinder and condensed into accumulated water， which further caused plasticity deformation of the rotor. After return-to-factory maintenance， the collision between rotary and static parts was effectively handled by replacing the steam seal teeth， adjusting the gap between rotary and static components and optimizing the unit start-up curve.

In this work, numerical models were developed to investigate the critical inclination of a pipeline to eliminate the water accumulation at the floor of the pipe carrying oil-water fluid. Computational fluid dynamics software was used to establish a geometric model of the pipe with various inclination angles, and a grid-independent verification was conducted to determine a reasonable meshing method. Quantitative relationships were determined between the pipe inclination angle and the affecting factors including the flow velocity, viscosity and the pipe diameter, where the water accumulation would not be able to occur. Generally, the critical inclination angle increases with the fluid flow velocity. The refluxing of water is the key mechanism causing the water accumulation at the bottom of the pipe. In addition to the fluid flow velocity, an increase in fluid viscosity and a decrease in the pipe diameter cause an increase of the critical inclination angle that the water phase can be carried away by oil. The model can be used to determine the critical inclination of pipelines carrying oil-water fluid to cause the water accumulation and the operating conditions that can eliminate the accumulation of water phase at the pipe floor.

• Employing a novel layer-scanning method, liquid water accumulation near the freezing front during freezing of non-frost-susceptible soils was observed. • Water migration independent of ice segregation, overlooked before, in the non-frost-susceptible soils was identified. • Determining the presence of ice segregation favors in exploring water migrations modes, micro frost heave and thick-layered ground ice formation. Investigating water migration in frozen ground is crucial for understanding the hydrothermal dynamics of frozen soil, which is central to frozen soil engineering (e.g., frost heave) and permafrost environments (e.g., ground ice formation). Previous studies have mostly focused on water migration related to ice segregation in frost-susceptible soils, but less on water migration that is independent of ice segregation in non-frost-susceptible soils. Using a novel layer-scanning method based on the nuclear magnetic resonance (NMR) techniques, the water migration dynamic was observed during the freezing of non-frost-susceptible loess under different drainage conditions (with or without water drainage). Results showed an apparent phenomenon of water migration to the freezing front (TFF) (layer L7) (i.e., water accumulation that is independent of ice segregation) occurred in the early freezing stage of non-frost-susceptible soils under no draining water conditions. The traditional water migration mode is related to ice segregation, a new water migration (including upward and downward) mechanism was proposed to reveal this water accumulation unrelated to ice segregation at TFF. The water accumulation at the freezing front is independent of ice segregation, and is attributed to 9% volume expansion due to pore ice formation in the frozen zone, causing water migration downward TFF; while the decrease of the pore volume of the unfrozen zone (being compressed) accounts for the water migration upward TFF. Investigation into whether ice segregation exists and different modes of water migrations (depending on ice segregation or not) will be greatly helpful for exploring the mechanisms of micro frost heave in the high-speed railway embankments and the thick-layered ground ice formation. [ABSTRACT FROM AUTHOR]

Influenced by climate change and urbanization, urban flood frequently occurs and represents a serious challenge for many cities. Therefore, it is necessary to generate refined predictions of urban floods, such as the prediction of water accumulation processes at water accumulation points, which is of great significance for supporting water-related managers to reduce flood losses. In this study, 16 combination schemes of rainfall sensitivity indicators were used to determine the optimal scheme for predicting the depth of accumulated water, and the gradient boosting decision tree (GBDT) algorithm in deep learning was used to build a prediction model of the accumulation process of urban stormy accumulation points. Among the 16 schemes, the relative error of scheme 1 is 15.39%, and the qualified rate is 92.86%. This scheme exhibits the highest accuracy for the prediction results of water accumulation depth. Given this finding, the GBDT algorithm was used to construct a regression prediction model of the water accumulation process based on the collected historical rainfall water accumulation data of 50 water accumulation points. The results demonstrated that the GBDT regression prediction model has a mean relative error of 19.77%, a qualified rate of 82.00%, and a peak average relative error of 5.48%, which verify the validity and applicability of the model for the real-time prediction of the process of water accumulation.

Wheat grain yield is anticipated to suffer from the increased temperatures expected under climate change. In particular, the effects of post-anthesis temperatures on grain growth and development must be better understood in order to improve crop models. Grain growth and development involve several processes, and we hypothesized that some of the most important processes, namely grain dry biomass and water accumulation, grain volume expansion, and endosperm cell proliferation, will have different thermal sensitivity. To assess this, we established temperature–response curves of these processes for steady post-anthesis temperatures between 15 °C and 36 °C. From anthesis to maturity, grain dry mass, water mass, volume, and endosperm cell number were monitored, whilst considering grain temperature. Different sensitivities to heat of these various processes were revealed. The rate of grain dry biomass accumulation increased linearly up to 25 °C, while the reciprocal of its duration increased linearly up to at least 32 °C. In contrast, the growth rates of traits contributing to grain expansion, such as increase in grain volume and cell numbers, had higher optimum temperatures, while the reciprocal of their durations were significantly lower. These temperature–response curves can contribute to improve current crop models, and allow targeting of specific mechanisms for genetic and genomic studies. [ABSTRACT FROM AUTHOR]

Aquaporins (AQPs) are a class of highly conserved integral membrane proteins that facilitate the uptake and transport of water and other small molecules across cell membranes. However, little is known about AQP genes in pomegranate (Punica granatum L.) and their potential role in water accumulation of the outer seed coat. We identified 38 PgrAQP genes in the pomegranate genome and divided them into five subfamilies based on a comparative analysis. Purifying selection played a role in the evolution of PgrAQP genes and a whole-genome duplication event in Myrtales may have contributed to the expansion of PgrTIP, PgrSIP, and PgrXIP genes. Transcriptome data analysis revealed that the PgrAQP genes exhibited different tissue-specific expression patterns. Among them, the transcript abundance of PgrPIPs were significantly higher than that of other subfamilies. The mRNA transcription levels of PgrPIP1.3, PgrPIP2.8, and PgrSIP1.2 showed a significant linear relationship with water accumulation in seed coats, indicating that PgrPIP1.3/PgrPIP2.8 located in the plasma membrane and PgrSIP1.2 proteins located on the tonoplast may be involved in water accumulation and contribute to the cell expansion of the outer seed coat, which then develops into juicy edible flesh. Overall, our results provided not only information on the characteristics and evolution of PgrAQPs, but also insights on the genetic improvement of outer seed coats.

ABSTRACT Forage biomass production and water storage (WS) was evaluated in cactus pear cv. Gigante fertilized with combinations of nitrogen (10, 70, 100, 130, and 190 kg ha−1 yr−1 N) and phosphorus (10, 70, 100, 130, and 190 kg ha−1 yr−1 P2O5) in annual (AH) and biennial (BH) harvest frequencies, in Quixadá and Tejuçuoca, Brazil. A randomized complete block design was used in a split-plot arrangement with four replications. In Quixadá, the maximum total forage biomass (TFB) recorded in the AH was 3,522.9 kg ha−1 yr−1 for the N/P2O5 combination of 134.6/190.0 kg ha−1 yr−1, and in the BH, the maximum TFB of 1,583.2 kg ha−1 yr−1 was recorded for the N/P2O5 combination of 114.6/136.8 kg ha−1 yr−1. In Tejuçuoca, the maximum TFB recorded in the AH was 9,783.0 kg ha−1 yr−1 for the N/P2O5 combination of 137.7/190.0 kg ha−1 yr−1, and in the BH, the maximum TFB of 12,124.0 kg ha−1 yr−1 was recorded for the N/P2O5 combination of 190.0/56.8 kg ha−1 yr−1. In Quixadá, the maximum WS recorded in the AH was 39.1 kg ha−1 mm−1 for the N/P2O5 combination of 161.0/190.0 kg ha−1 yr−1, and in the BH, the maximum WS of 11.3 kg ha−1 mm−1 was recorded for the N/P2O5 combination of 113.5/158.7 kg ha−1 yr−1. In Tejuçuoca, the maximum WS recorded in the AH was 196.1 kg ha−1 mm−1 for the N/P2O5 combination of 190.0/190.0 kg ha−1 yr−1, and in the BH, the maximum WS of 265.5 kg ha−1 mm−1 was recorded for the N/P2O5 combination of 190.0/10.0 kg ha−1 yr−1. To achieve the persistence and longevity of the cactus pear cv. Gigante, the management with BH and fertilization with the N/P2O5 combination of 114.6/136.8 kg ha−1 yr−1 (in regions similar to Quixadá) and N/P2O5 combination of 190.0/56.8 kg ha−1 yr−1 (in regions similar to Tejuçuoca) is recommended.

In order to quantify the migration rule of water in composite lining canal foundation soil during the freeze-thaw process, the outdoor prototype test is performed to prove the change rules of water in different positions and depths of the rigidflexible mixed composite lining canal foundation during the whole freeze-thaw cycle. The prototype observation test shows that during the freezing period, the water content within the 0~80cm depth of the canal foundation soil increases with the depth, and that within the depth of 80~160cm decreases gradually with the depth. In the freezing period, water accumulates in the depth of 60 ~ 80cm, with a maximum water transfer amount of +13.2%, which occurs at the canal bottom. In the thawing period, the maximum water content also occurs at the canal bottom, with a maximum water transfer amount of -11.0%. Through the laboratory test of soil samples, the water migration development and change rules of the canal foundation soil, under different moisture contents and temperature gradients are studied in unilateral pattern. In the case of the same top plate control temperature, soil samples with similar initial water contents have similar water transfer amounts. The samples with higher initial water content have higher water transfer amount, with higher water accumulation, normally accumulating in the depth of 16~18cm. The results indicate that high water contents make it easy to gather water in soil samples during the freezing period. [ABSTRACT FROM AUTHOR]

This dataset gathers the initial formation and the evolution of water content and distribution, as well as water evacuation, within a lung-inspired PEM (proton exchange membrane) fuel cell with a 50 cm 2 active area for various operating conditions such as cell pressure, relative humidity of the reactant (anode and cathode), temperature, and cell current density. Neutron imaging was used since it has been shown to be an effective technique for quantitative analysis of water distribution, obtaining the thickness of the water with the Lambert-Beer law, thus obtaining the numerical data that composes the tables and graphs in this dataset. A series of videos compiling the individual images obtained through neutron imaging, showing the water distribution evolution are presented. Numerical and graphical compilation of the amount of water in a cell through time in different regions of the cell and for a total of 10 experiments are provided. This dataset provides a deeper knowledge on the complex phenomena that liquid water is subjected to in fuel cells along time, as well as a basis for an experimental validation for Computational Fluid Dynamics (CFD) simulations., (© 2024 The Authors.)

Staphylococcus aureus spreads rapidly on the surface of soft agar medium. The spreading depends on the synthesis of biosurfactants, i.e., phenol soluble modulins (PSMs), which facilitate colony spreading of S. aureus. Our earlier study demonstrated that water accumulates in a colony is important to modulate colony spreading of S. aureus. The current study screened a transposon-based mutant library of S. aureus HG001 and obtained four non-spreading mutants with mutations in hemY and ctaA, which are involved in heme synthesis. The spreading ability of these mutants was restored when the mutants are transformed with a plasmid encoding hemY or ctaA, respectively. HemY mutants, which do not synthesize heme B, were able to spread on agar medium supplemented with hemin, a heme B derivative. By contrast, hemin supplementation did not rescue the spreading of the ctaA mutant, which lacks heme B and heme A, indicating that heme A is also critical for colony spreading. Moreover, mutations in hemY and ctaA had little effect on PSMs production but affect ATP production and water accumulation in the colony. In conclusion, this study sheds light on the role of heme synthesis and energy production in the regulation of S. aureus colony spreading, which is important for understanding the movement mechanisms of bacteria lacking a motor apparatus.

Staphylococcus aureus spreads rapidly on the surface of soft agar medium. The spreading depends on the synthesis of biosurfactants, i.e., phenol soluble modulins (PSMs), which facilitate colony spreading of S. aureus. Our earlier study demonstrated that water accumulates in a colony is important to modulate colony spreading of S. aureus. The current study screened a transposon-based mutant library of S. aureus HG001 and obtained four non-spreading mutants with mutations in hemY and ctaA , which are involved in heme synthesis. The spreading ability of these mutants was restored when the mutants are transformed with a plasmid encoding hemY or ctaA , respectively. HemY mutants, which do not synthesize heme B, were able to spread on agar medium supplemented with hemin, a heme B derivative. By contrast, hemin supplementation did not rescue the spreading of the ctaA mutant, which lacks heme B and heme A, indicating that heme A is also critical for colony spreading. Moreover, mutations in hemY and ctaA had little effect on PSMs production but affect ATP production and water accumulation in the colony. In conclusion, this study sheds light on the role of heme synthesis and energy production in the regulation of S. aureus colony spreading, which is important for understanding the movement mechanisms of bacteria lacking a motor apparatus. [ABSTRACT FROM AUTHOR]

In order to avoid the corrosion risk caused by the internal water in the pipeline, the transnational long distance crude oil pipeline carries out the accumulated water in the low-lying part of the topographic undulating pipeline through the flow of the crude oil itself. According to the characteristics of oil-water two-phase flow state and oil-water interface morphology in upward crude oil pipeline, Open- FOAM software was used to simulate and analyze the oil-water interface. InterFoam solver based on VOF model was selected to solve the dynamic equation of oil-water interface. The experimental data and numerical simulation results under the same conditions are compared and verified. The results show that the method of simulating the water carrying flow with OpenFOAM was feasible. The oil-water interface of upward inclined pipeline is related to the wettability of the wall. When the contact angle θ is 30° (hydrophilic wall surface), the oil-water interface appears wave shape, and when the contact angle θ is 120° (hydrophobic wall surface), the water accumulates into water mass on the upward inclined pipe. The flow rate of water increases with the increase of contact angle θ and crude oil velocity, and when the flow rate of crude oil exceeds the critical velocity of Kelvin-Helmholtz interface fluctuation, it will lead to the accelerated movement of water. [ABSTRACT FROM AUTHOR]

The effects of water accumulation at the interface of gas diffusion layer (GDL) and gas supplying channel on the water distribution in polymer electrolyte membrane fuel cells (PEMFCs) is analyzed. The amount of water at the interface and in the GDL are quantified using X-ray. Quantitative analyses show that the value of the criterion of water accumulation that can affect the water distribution is in the water saturation range of 0.22–0.24. The amount of water in the GDL increases with the water accumulated at the beginning of the water generation cycle. However, it remains constant after the water accumulation exceeds a criterion value. The result shows that the water accumulation at the interface should be investigated to understand the water distribution in PEMFC. The water distribution in PEMFC cannot be analyzed based on the steady state concept but can be analyzed based on the concept of cyclic process. • Water accumulation at the interface GDL and gas supplying channel is visualized and analyzed quantitatively. • The relation between water accumulation at the interface and water distribution in PEMFC is analyzed quantitatively. • The criterion of water accumulation at the interface that can affect the water distribution in PEMFC is proposed. • The water distribution in PEMFC should be investigated not based on the steady state concept but based on the cyclic process. [ABSTRACT FROM AUTHOR]

Highlights • A single solid oxide fuel cell was operated under internal reforming for ∼500 h. • In-situ analysis techniques were used to fully characterize the cell performance. • Localized gas analyses and temperature measurements in the fuel electrode were performed in-operando. • The cell showed an unstable voltage coupled to an early visible performance decay. • The main source of degradation was the presence of water at the cathode side. Abstract To simulate realistic operating conditions and analyze their effect on the performance of planar intermediate temperature solid oxide fuel cell systems, a large-area (11 × 11 cm2) anode-supported single cell was tested for ∼500 h, at 650 °C and 245 mA/cm2, corresponding to 43% of fuel utilization, running on a simulated pre-reformate natural gas composition. To correlate the evolution in the cell performance (i.e. voltage loss; total resistance) with specific thermo-fluid-physicochemical processes, localized gas analyses and temperature measurements through the anode surface, using a very particular spot-sampling set-up, as well as electrochemical impedance spectra and polarization curves, were frequently carried out. The impedance spectra have been analyzed through the distribution of relaxation times method and the cell study complemented with a post-mortem analysis. During its operation, the cell sequentially experienced several events to which thermal-cycling and intrinsic degradation have been correlated. Experimental results revealed that cathode humidification was the dominant contribution to the performance degradation, where strontium segregation has been observed and the formation of some insulating phases is suspected. This work is one of the first attempts to carry out an endurance test with real-time diagnosis by in-situ and in-operando gas and temperature analysis, thus monitoring in real conditions the electrochemical, chemical and thermal activity of the anode side in a commercial single solid oxide fuel cell. [ABSTRACT FROM AUTHOR]

In this study, the change of electrochemical parameters during the gradual water accumulation of a polymer electrolyte fuel cell (PEFC) are estimated using electrochemical impedance spectroscopy (EIS) measurements and an impedance model based on electrode theory during a two‐step oxygen reduction reaction (ORR). EIS measurements were carried out in a 5 cm2 H2/O2 PEFC operated under a dead‐ended configuration of the gas reactants and during gradual accumulation of water. Kramers‐Kronig evaluation demonstrated that the EIS measurements comply with stability and linearity properties and the inductive loops featured at low frequencies are attributed to electrochemical mechanisms within the PEFC and not to instability during gradual water accumulation. The impedance model has been reported in a previous study and simulates inductive loops at low frequencies which are attributed to platinum oxide formation during the ORR. The estimated parameters obtained from this EIS‐modeling analysis can provide an insight into the decrease in PEFC performance during flooding conditions. A further qualitative analysis considering the effect of long‐term water accumulation on the oxygen‐reduction charge transfer resistance is discussed. It is possible to have an insight into the physical mechanisms of the PEFC, by combining different experimental techniques and fundamental theory in a complimentary manner. [ABSTRACT FROM AUTHOR]

In the second half of the twentieth century, the Volga and the Danube were regulated. As a result, channel processes and the processes of alluvium deposition and humus accumulation in soils, surface and underground waters were changed. The comparative analysis of Volga-Akhtuba and Lower Dunabe floodplains is carried out in the article. It was found that due to the regulated flow, hydraulic engineering and land reclamation construction had provoked direct (immediate) changes in natural systems, as well as indirect (mediated) changes in the landscapes. The Volga-Akhtuba floodplain is characterized by the dominance of indirect effects resulting from changes in the hydrological regime of the Volga to produce cheap electricity and irrigation of vegetable plantations. Therefore, the landscape can be attributed to the natural type. The Lower Danube is characterized by immediate impact, namely, leveling the surface and creating a drainage system, the purpose of which was to increase the area of agricultural land within the floodplain and to decrease the number of catastrophic floods. This led to the formation of technogenically anthropogenic landscape within the floodplain. The components and relationships in the downstream of the Volga hydroelectric are degraded, but not destroyed in comparison with the Great Balta Braila, so the natural complexes of the Volga-Akhtuba floodplain and associated natural processes can be restored by means of environmental management. Abnormalities in the flow regulation of the Volga and the Danube led to the destruction of hydraulic connection between the two bodies of water floodplains, alluvial processes slow down and change in the level of groundwater. Within the floodplain the erosion and accumulation also lowered their rates. The river channels, on the contrary, increased erosion and accumulation, causing the decrease of rivers level, and there is an active formation of braid, shoals and islands.

Abstract: In this article, water accumulation abnormalities in small‐scale lungs are numerically and experimentally studied at microwave regime. The noninvasive passive microwave sensing platform considered here comprises the use of two low‐profile patch antennas. The sensors, operating at the ISM band, are attached back‐to‐back to the skin surface of the lungs. By monitoring the sudden changes of computed transmission coefficient (both magnitude and phase) between the two sensors, qualitative measures can be developed to estimate whether significant water accumulation in lungs take place or not, which can provide further insights at an early medical diagnosis. Several numerical case studies are developed and studied here that mimic various water accumulation scenarios within the modeled lungs. A practical small‐scale yet low‐cost platform integrated with the microwave sensors was demonstrated and validated. The results correlate reasonably well with numerical results. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water flooding at the cathode is a critical issue in polymer electrolyte membrane fuel cells, since it will block the oxygen transport, resulting in a large concentration loss. To address this issue, two tapered flow fields with varying height or width are proposed in this study, as the tapered channels can gradually increase flow velocity which is beneficial in water removal. To confirm the proposed function, both experiments and simulation are performed. The results prove that the tapered flow fields with high velocity at the downstream region can significantly enhance water removal in flow channels, which avoids the mass transport limitation and improves the cell performance at high current densities. Additionally, the tapered design can also enhance the under-rib convection between adjacent channels, which helps to remove accumulated water in the gas diffusion layer. [ABSTRACT FROM AUTHOR]

Diurnal soil temperature fluctuations are the prime cause for subsurface water vapor fluxes. In arid and semi-arid areas, water vapor flux is the dominant means of soil water redistribution. The directions of water vapor flux shift from upward to downward diurnally following the variations of the soil thermal gradient. A water vapor diode (WVD), acting as a check valve, allows water vapor flux in one direction but heat flux in both directions. By installing a subsurface WVD, it is possible to impose direction-controlled vapor fluxes, and WVDs can be used to accumulate or remove water in particular soil layers. The egg carton shape, with pores situated at selected peaks and valleys, is a possible design for WVDs. In this study, we provide the concept and the properties of the ideal WVDs, and we discuss four WVD configurations to control soil water redistribution. Numerical simulation is used to evaluate the impacts of the ideal WVDs. The results indicate that WVDs can increase local water contents by at least 0.1 m 3 m - 3 in a silt loam. For a fixed initial water and thermal condition, the effect of WVDs is related to the deployment depth and distance between two consecutive WVDs. WVDs can be used to manipulate soil water redistribution and accumulate water at specific depths to support plant growth. The numerical simulation results indicate the potential effectiveness of the ideal WVDs, and field tests should be performed to determine their function under specific soil conditions. [ABSTRACT FROM AUTHOR]

Cytoplasmic male sterile (CMS) rice has been widely used for hybrid rice seed production in China. However, CMS rice suffers from undesirable flowering habits including scattered floret opening time (FOT), which causes different FOTs among parental rice plants and greatly reduces hybrid rice seed production. Little is known about the mechanism of scattered FOT in CMS rice. Our results demonstrate that scattered FOT in CMS rice Zhenshan 97A (ZS97A) resulted from the lack of a driving force to open florets, which was directly caused by retarded lodicule expansion. Our results indicate that retarded lodicule expansion in ZS97A was caused by reduced water accumulation due to retarded accumulation of osmotic regulation substances (ORSs). Further, the retardation in accumulation of ORSs and water were caused by jasmonic acid (JA) deficiency, resulting from down-regulation of OsAOC expression. Applying JA restored scattered FOT in ZS97A by promoting ORS and water accumulation, and inducing the expansion of the lodicules. Taken together, JA deficiency inhibited lodicule expansion by retarding the accumulation of ORSs and water, leading to scattered FOT in CMS rice ZS97A. [ABSTRACT FROM AUTHOR]

The intrinsic effect of properties of a self-supporting microporous layer (MPL) on the performance of proton exchange membrane fuel cells (PEMFCs) is identified. First, a self-supporting MPL is fabricated and applied to a gas diffusion layer (GDL) of a PEMFC, when the GDL is either an integrated sample composed of a gas diffusion backing (GDB, i.e., carbon paper) combined with MPL or a sample with only MPL. Cell performance tests reveal that, the same as the MPL fabricated by the coating method, the self-supporting MPL on the GDB improves the cell performance at high current density. Furthermore, the GDL composed only of the MPL (i.e., GDB-free GDL) shows better performance than does the integrated GDB/MPL GDL. These results along with literature data strongly suggest that the low thermal conductivity of MPL induces a high temperature throughout the GDL, and thus vapor diffusion is dominant in the transport of product water through the MPL. [ABSTRACT FROM AUTHOR]

To estimate the potential for residual antimicrobial solution carryover, surface water accumulation and loss was measured on post-chill carcasses that were either dipped or sprayed with water. For all experiments, broilers were slaughtered, soft or hard scalded, defeathered, and eviscerated. Carcasses were immersion chilled, allowed to drip, and post-chill carcass weight (CW) recorded. For water dip treatment, carcasses were dipped for 0.5 min in water and hung by a wing (n = 33) or a leg (n = 30) and CW recorded at 0, 0.5, 1, 2, and 5 min post-dip. For water spray treatment, individual carcasses were hung by either the wings (n = 35) or legs (n = 34) from a shackle suspended from a scale. Water was sprayed at 80 psi and post-spray CW recorded. Initial water accumulation (0 min) for dipped carcasses was not significantly different (P > 0.05) for carcasses hung by the leg (101.0 g) or wing (108.8 g). Following the 5 min drip time, 31 g of water remained on the carcasses hung by the leg and only 10 g on carcasses hung by the wing (P < 0.05). When carcasses were sprayed with water, initial water accumulation (0 min) was 62 g for carcasses hung by the legs and 60 g for carcasses hung by the wings (P > 0.05). Following the 5 min drip time, 1 g or no water remained on the sprayed carcasses (P > 0.05). Carcasses that were dipped and hung by a leg for 5 min retained significantly more water (31 g) than carcasses that were dipped and hung by a wing (10 g) or sprayed carcasses hung either way (0.3 g) (P < 0.05). Post-chill water dip resulted in significantly higher initial carcass water accumulation than spraying (105 g vs. 61 g, P < 0.05). Carcass orientation during dripping only affected the amount of retained water for dipped carcasses. Dipped carcasses hung by a leg have the highest potential for residual carcass antimicrobial solution carryover and sprayed carcasses hung by either orientation have the lowest potential for residual antimicrobial solution carryover. [ABSTRACT FROM AUTHOR]

Copyright of Inzynieria Mineralna is the property of Polskie Towarzystwo Przerobki Kopalin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Photoacoustic imaging (PAI), providing the unique contrast of optical absorption and the superb scalability of spatial resolution and penetration, has emerged as an enabling technique in both basic and translational brain research. In this paper, first, mechanisms behind neuro-PAI of endogenous absorber-encoded functional information (e.g., the concentration of hemoglobin, the oxygen saturation of hemoglobin, blood flow, oxygen metabolism, and water accumulation) and exogenous probe-labeled molecular targets (e.g., neural activity, glucose uptake, aberrant protein aggregation, and malignancy) are introduced. Then, two technical innovations—functional connectivity photoacoustic tomography and high-speed functional photoacoustic microscopy—for spatio-temporal interrogation of the brain at resting and activated states are highlighted, and two application niches in vascular cognitive impairment and brain cancer are discussed. Finally, the prospect of neuro-PAI is envisioned. [ABSTRACT FROM PUBLISHER]

PEMFC (Proton exchange membrane fuel cell) operated under dead-ended anode mode is an effective and simple device for high hydrogen utilization. Herein, the operation characteristics of PEMFC with dead-ended anode are systematically investigated under various operating temperature, anode inlet pressure, and cathode stoichiometry. In each operating parameter, the solenoid valve located at the anode outlet is closed all the time and the hydrogen utilization reaches 100%. It has been found that fuel cell with dead-ended anode can operate continuously for 26 h with slight decrease in output voltage under 600 mA cm −2 at 65 °C, 80% of RH (relative humidity) with hydrogen inlet pressure of 0.4 bar gauge and oxygen stoichiometry of 4.0. After accumulated 150 h operation under dead-ended anode mode, the degradation of according MEA (membrane electrode assembly) has been analyzed using CV (cyclic voltammetry) and cross-sectional morphology. The results show that the accumulation of water induced corrosion of catalyst layer is responsible for the decrease in ECSA (electrochemical surface area) of catalyst layer and the according degradation of cell performance. Moreover, the degradation of catalyst layer became much more serious at the vicinity of cathode outlet than the other regions. [ABSTRACT FROM AUTHOR]

Following an application from Nutrilinks Sarl, submitted pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Belgium, the Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Vitis vinifera L. seeds extract and “helps to drain the body in case of water accumulation”. The Panel considers that the food constituent which is the subject of the health claim is sufficiently characterised. The claimed effect proposed by the applicant is “helps to drain the body in case of water accumulation”. Upon EFSA’s request for clarification on the specific physiological function that is the subject of the health claim, together with the outcome measures which could be used for the scientific evaluation of that function, the applicant indicated that “increase of body drainage” was a beneficial physiological effect in the context of “a normal venous circulation in the legs”. The applicant acknowledged that this claim referred to the same physiological function of the body as another health claim application on Vitis vinifera L. seeds extract and maintenance of normal venous blood flow. The Panel considers that maintenance of normal venous blood flow is a beneficial physiological effect. A claim on Vitis vinifera L. seeds extract and maintenance of normal venous blood flow has already been assessed by the Panel with an unfavourable outcome. The reference provided by the applicant for the scientific substantiation of this claim was already considered in the previous submission.