OBJECTIVE: Baby skin differs significantly from adult skin and requires special care. The Cussons Baby Sensicare Range (Sensicare) of products has been specifically formulated for baby skin and a range of standard cos...OBJECTIVE: Baby skin differs significantly from adult skin and requires special care. The Cussons Baby Sensicare Range (Sensicare) of products has been specifically formulated for baby skin and a range of standard cosmetic clinical tests were conducted in adult females with dry skin to evaluate the effectiveness of the range on skin moisturization and barrier function. METHODS: The studies were within subject, controlled, single blind studies. For the Sensicare Body Wash skin moisturization (Corneometer) was measured before application and after 7 and 14 days of twice daily use. For the Sensicare Moisturizing Lotion and Sensicare Soothing Cream skin moisturization was measured before application and at 2, 4, 6, 8 and 24 hours after a single application;skin elasticity (Cutometer) and transepidermal water loss (TEWL, Tewameter) were assessed before and after 14 days of twice daily use;and skin erythema (Mexameter) before induction with sodium lauryl sulphate (SLS), and at 30 mins, 24 and 48 hours after patch removal. Changes from baseline and changes versus control were evaluated. RESULTS: Thirty to thirty-five subjects completed each study. Skin moisture content was significantly increased from baseline for all Cussons Baby Sensicare Products (p < 0.05 for Hair & Body Wash;and p < 0.001 for Cream & Lotion). Changes from baseline in skin elasticity were significantly superior to control (unperfumed liquid soap) after 14 days twice daily use of the Lotion, and Cream (p < 0.05). There were no significant changes from baseline or significant differences from control in TEWL for the Lotion, or Cream. The increases in the average skin erythema index were significantly smaller for the Lotion, and Cream 30 minutes following SLS patch removal (p < 0.05 v sterile water, p < 0.001 v no treatment for both products). All the Sensicare products were well tolerated. CONCLUSION: These studies support the use of the Cussons Baby Sensicare range of products for new born, sensitive and eczema prone skin.展开更多
Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion di...Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion discrete model that is capable of dynamically assessing the effect of cracking on moisture diffusion and allowing moisture to be discontinuous on both sides of the cracks.Then,the parametric analysis of the moisture exchange coefficient in the 3D moisture diffusion discrete model is carried out for moisture diffusion in continuous media,and the selection criterion of the moisture exchange coefficient for the unbroken cohesive element is given.Subsequently,an example of moisture migration in a medium with one crack is provided to illustrate the crack hindering effect on moisture migration.Finally,combining the 3D moisture diffusion discrete model with the finite-discrete element method(FDEM),the moisture diffusion-fracture coupling model is built to study the desiccation cracking in a strip soil and the crack pattern of a rectangular soil.The evolution of crack area and volume with moisture content is quantitatively analyzed.The modeling number and average width of cracks in the strip soil show a good consistency with the experimental results,and the crack pattern of the rectangular soil matches well with the existing numerical results,validating the coupled moisture diffusion-fracture model.Additionally,the parametric study of soil desiccation cracking is performed.The developed model offers a powerful tool for exploring soil desiccation cracking.展开更多
This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked asphalt.Thermodynamic parameters,morphological characteristics,interfacial healing energy,and...This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked asphalt.Thermodynamic parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in self-healing.The results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing interface.Hydroxyl groups with different bonding states increase the interfacial adsorption capacity of water-soaked asphalt.The interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"phenomenon.The former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the components.Furthermore,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt.展开更多
During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s...During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.展开更多
The creep-slip behavior of creeping landslides is closely related to the creep characteristics of slope rock.This study analyzed the creep behavior of ultra-soft mudstone from the Gaomiao landslide in Haidong City,Qin...The creep-slip behavior of creeping landslides is closely related to the creep characteristics of slope rock.This study analyzed the creep behavior of ultra-soft mudstone from the Gaomiao landslide in Haidong City,Qinghai Province,China.Uniaxial creep tests were carried out on ultra-soft mudstone with various moisture contents.The test results indicated that the creep duration of the rock sample with a natural moisture content of 9%is 2400 times longer than that of the sample with a natural moisture content of 13%,while its accumulated strain is 70%of the latter.For the rock sample with a natural moisture content of 9.80%,the creep duration under 0.5 MPa load is 80%of that under 0.25 MPa load,yet the accumulated strain is 1.4 times greater.Additionally,porosity significantly influences the creep behavior of mudstone.Analysis of the cause of the Gaomiao landslide and field monitoring data indicates that the instability of the Gaomiao landslide is related to the moisture content of the landslip mass and external forces.The creep-slip curves of landslides and the creep deformation curves of rocks share a common trend.Precisely identifying the moment when the shift occurs from steady state creep to accelerated creep is critical for comprehending slope instability and rock failure.Moreover,this study delves deeper into the issue of the consistency between landslide creep and rock deformation.展开更多
Plant root systems serve as a natural reinforcing material,significantly improving soil stability.Furthermore,the tensile strength of soil is crucial in mitigating the formation of cracks.Consequently,this study aims ...Plant root systems serve as a natural reinforcing material,significantly improving soil stability.Furthermore,the tensile strength of soil is crucial in mitigating the formation of cracks.Consequently,this study aims to investigate the influence of plant roots on the tensile strength of soil.For this investigation,Amorpha fruticose was selected due to its large root diameter and the ease of root extraction.Indoor tensile tests were conducted on individual roots and root-soil complexes under three varying factors.The results indicate a power law relationship between root diameter and tensile strength.Increased root content and dry density notably enhance the tensile strength of the root-soil complex while roots mitigate damage associated with soil brittleness.When root content increases from 0 to 10,the maximum enhancement in tensile strength of the root-soil complex reaches 42.3 kPa.The tensile strength of the root-soil complex at a dry density of 1.7 g/cm^(3)is four to five times greater than that of the complex at a dry density of 1.4 g/cm^(3).Moreover,as moisture content increases,the tensile strength of the root-soil complex initially rises before declining,with an increase range of 7.7-35.8 kPa.These findings provide a scientific basis for understanding the role of vegetation roots in soil tensile strength and for guiding slope reinforcement strategies.展开更多
Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These su...Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These surge events typically occur for days in the early-summer season(from April to June)and can lead to heavy rains in South China.This study categorizes surge events into three types of flow patterns and examines their multiscale variations and impacts on rainfall.The first type occurs mainly in April,with the southeasterlies enhanced by a deepening trough in South China and the western Pacific subtropical high established over the SCS.The second type of surge events mostly appears in June,featuring the prevailing southwesterlies of summer monsoon from the Indian Ocean during the active phases of intraseasonal oscillations.Most surge events exhibit semi-diurnal variations with morning and afternoon peaks of northward moisture fluxes.Specifically,the first type features a dominant afternoon peak,while the second type shows a dominant early-morning peak,which is induced by thermal contrast between the Indochina Peninsula and the SCS.In general,the surge events enhance moisture convergence and increase rainfall downstream in South China,but they show some regional differences.The second type strengthens moisture convergence and rainfall in coastal regions with a morning peak.In contrast,the first type enhances inland rainfall with a morning peak,while moisture divergence dominates coastal regions.The third type of surge events denotes transitional conditions between the first two types,in terms of atmospheric circulations,diurnal cycles,and rainfall patterns.These results highlight a diversity of regional moisture surges and related rainfall ranging from diurnal to sub-seasonal scales.展开更多
This study investigates the potential of bamboo ash (CB) and sugarcane bagasse ash (CBCS) as sustainable filler and reinforcement materials to optimize the moisture resistance of bituminous concrete. The research addr...This study investigates the potential of bamboo ash (CB) and sugarcane bagasse ash (CBCS) as sustainable filler and reinforcement materials to optimize the moisture resistance of bituminous concrete. The research addresses critical environmental and economic challenges by proposing the valorization of these agricultural by-products, which are rich in silica (SiO2) and possess pozzolanic properties, to improve the mechanical performance and durability of bituminous mixtures. Material characterization revealed the suitability of CB and CBCS due to their mineralogical composition and adherence to engineering standards for filler materials. Four formulations were tested, including a control sample and mixtures incorporating 0.2%, 0.3%, and 0.4% CB and CBCS. The mixture with 0.3% of each ash demonstrated optimal results, significantly enhancing Marshall stability, compactness, and fatigue resistance compared to the control sample. Durability assessments, including water sensitivity and freeze-thaw cycle tests, indicated superior performance of the modified mixtures, with reduced moisture-induced damage and enhanced resistance to extreme climatic conditions. Scanning Electron Microscopy (SEM) analyses confirmed improved microstructural integrity, showing strong adhesion between ash particles and the bitumen matrix, reduced porosity, and limited microcracking. In addition to mechanical and durability improvements, the integration of CB and CBCS offers substantial environmental and economic benefits. The study demonstrates a reduction in CO2 emissions and production costs, positioning these ashes as viable solutions for sustainable road construction. This research underscores the potential of incorporating agricultural by-products in bituminous concrete, achieving dual benefits: enhancing infrastructure durability and promoting sustainable resource utilization.展开更多
The skin’s primary function is to protect the body against a spectrum of environmental stressors, including mechanical insults, microorganisms, chemicals, and allergens. Located in the outermost layers, the primary s...The skin’s primary function is to protect the body against a spectrum of environmental stressors, including mechanical insults, microorganisms, chemicals, and allergens. Located in the outermost layers, the primary structures and components responsible for the skin’s barrier function are susceptible to environmental variables, dermatological conditions, and the aging process. The ensuing alterations to structure, composition, and organizational attributes of the epidermal barrier can impact its integrity and functionality. The aim of this study was to assess the effect of a novel complex composed of a ceramide, energizing peptide, and Camu Camu extract (SUPCERAT<sup>TM</sup> complex) on specific markers of epidermal barrier integrity, as well as epidermal and dermal function. All the experiments were conducted on fresh human abdominal skin explants. Intradermal production of hyaluronic acid, epidermal claudin-1, and ceramide synthase 3 expressions, as well as epidermal lipids content were assessed using specific fluorescent stainings on ex vivo skin after the application of the complex or placebo. Additionally, dermal elastase and collagenase activities were assessed using in tubo enzymatic assays. Lastly, the effect of a cosmetic cream containing SUPCERAT<sup>TM</sup> complex was assessed using subjective Global Aesthetic Improvement Scale (GAIS) in a small cohort of patients after 60 days of use. The application of the SUPCERAT<sup>TM</sup> complex on ex vivo skin led to significant increase in dermal hyaluronic acid content and epidermal activity of claudin-1, ceramide synthase 3 and epidermal ceramide content. Furthermore, in tubo enzymatic assays demonstrated inhibition of both dermal elastase and collagenase activities. In addition, the patient-reported results indicated significant improvements in skin quality and appearance. .展开更多
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop...Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa.展开更多
Accurate soil moisture(SM)prediction is critical for understanding hydrological processes.Physics-based(PB)models exhibit large uncertainties in SM predictions arising from uncertain parameterizations and insufficient...Accurate soil moisture(SM)prediction is critical for understanding hydrological processes.Physics-based(PB)models exhibit large uncertainties in SM predictions arising from uncertain parameterizations and insufficient representation of land-surface processes.In addition to PB models,deep learning(DL)models have been widely used in SM predictions recently.However,few pure DL models have notably high success rates due to lacking physical information.Thus,we developed hybrid models to effectively integrate the outputs of PB models into DL models to improve SM predictions.To this end,we first developed a hybrid model based on the attention mechanism to take advantage of PB models at each forecast time scale(attention model).We further built an ensemble model that combined the advantages of different hybrid schemes(ensemble model).We utilized SM forecasts from the Global Forecast System to enhance the convolutional long short-term memory(ConvLSTM)model for 1–16 days of SM predictions.The performances of the proposed hybrid models were investigated and compared with two existing hybrid models.The results showed that the attention model could leverage benefits of PB models and achieved the best predictability of drought events among the different hybrid models.Moreover,the ensemble model performed best among all hybrid models at all forecast time scales and different soil conditions.It is highlighted that the ensemble model outperformed the pure DL model over 79.5%of in situ stations for 16-day predictions.These findings suggest that our proposed hybrid models can adequately exploit the benefits of PB model outputs to aid DL models in making SM predictions.展开更多
The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested tha...The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected event.However,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain unclear.By using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in 2020.Results show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST backgrounds.The intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒July.The intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 mei-yu.In contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil moisture.The roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System Model.Their synergistic impacts yield a notable 32%increase in YRB precipitation.Our findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.展开更多
Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses upli...Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various excavation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks expedite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack expansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are explored. The number of tensile and shear cracks increases with greater excavation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways.展开更多
In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture diffusivity.The problem aims to analyze the interconnection betw...In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture diffusivity.The problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic waves.The study examines the photothermoelasticity transport process while considering the impact of moisture diffusivity.By employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic medium.These equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive relationships.Mechanical stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace domain.By employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under study.Referencemoisture,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.展开更多
Erratum to:J.Mt.Sci.(2024)21(5):1663-1682 https://doi.org/10.1007/s11629-023-8561-0 During the production process,the first author’s name was wrongly written as“Rang Huang”in the metadata.The correct name for the f...Erratum to:J.Mt.Sci.(2024)21(5):1663-1682 https://doi.org/10.1007/s11629-023-8561-0 During the production process,the first author’s name was wrongly written as“Rang Huang”in the metadata.The correct name for the first author is“Kang Huang”.The first author’s name in the fulltext pdf is correct.展开更多
Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different area...Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation.展开更多
The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer data.This SI...The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer data.This SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice temperature.The relationship between the SIT and PR was found to be almost stable across the five selected regions.The SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction sensors.The results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT data.The proposed algorithm can be used for thin sea ice thickness(<1.0 m)estimation in the Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.展开更多
Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,...Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,which affects the accuracy of local moisture recycling.In this study,a total of 18 stations from four typical areas in China were selected to compare the performance of isotope-based linear and Bayesian mixing models and to determine local moisture recycling ratio.Among the three vapor sources including advection,transpiration,and surface evaporation,the advection vapor usually played a dominant role,and the contribution of surface evaporation was less than that of transpiration.When the abnormal values were ignored,the arithmetic averages of differences between isotope-based linear and the Bayesian mixing models were 0.9%for transpiration,0.2%for surface evaporation,and–1.1%for advection,respectively,and the medians were 0.5%,0.2%,and–0.8%,respectively.The importance of transpiration was slightly less for most cases when the Bayesian mixing model was applied,and the contribution of advection was relatively larger.The Bayesian mixing model was found to perform better in determining an efficient solution since linear model sometimes resulted in negative contribution ratios.Sensitivity test with two isotope scenarios indicated that the Bayesian model had a relatively low sensitivity to the changes in isotope input,and it was important to accurately estimate the isotopes in precipitation vapor.Generally,the Bayesian mixing model should be recommended instead of a linear model.The findings are useful for understanding the performance of isotope-based linear and Bayesian mixing models under various climate backgrounds.展开更多
Lithium hexafluorophosphate(LiPF_(6)),the most commonly used lithium battery electrolyte salt,is vulnerable to heat and humidity.Quantitative and qualitative determination the variation of LiPF_(6)have always relied o...Lithium hexafluorophosphate(LiPF_(6)),the most commonly used lithium battery electrolyte salt,is vulnerable to heat and humidity.Quantitative and qualitative determination the variation of LiPF_(6)have always relied on advanced equipment.Herein,we develop a fast,convenient,high-selective fluorescence detection method based on metal-organic cages(MOC),whose emission is enhanced by nearly 20 times in the presence of LiPF_(6)with good stability and photobleaching resistance.The fluorescent probe can also detect moisture in battery electrolyte.We propose and verify that the luminescence enhancement is due to the presence of hydrogen bond-induced enhanced emission effect in cages.Fluorescent excitation-emission matrix spectra and variable-temperature nuclear magnetic resonance spectroscopy are employed to clarify the role of hydrogen bonds in vip-loaded cages.Density functional theory(DFT)calculation is applied to simulate the structure of host-vip complexes and estimate the adsorption energy involved in the system.The precisely matched lock-and-key model paves a new way for designing and fabricating novel host structures,enabling specific recognition of other target compounds.展开更多
In order to explore the effect of artificial accelerated aging temperature on the performance of carbon fiber/epoxy resin composites,we used artificial seawater as the aging medium,designed the aging environment of se...In order to explore the effect of artificial accelerated aging temperature on the performance of carbon fiber/epoxy resin composites,we used artificial seawater as the aging medium,designed the aging environment of seawater at different temperatures under normal pressure,and studied the aging behavior of carbon fiber/epoxy composites.The infrared spectroscopy results show that,with the increase of aging temperature,the degree of hydrolysis of the composite is greater.At the same time,after 250 days of aging of artificial seawater at regular temperature,40 and 60 ℃,the moisture absorption rates of composite materials were 0.45%,0.63%,and 1.05%,and the retention rates of interlaminar shear strength were 91%,78%,and 62%,respectively.It is shown that the temperature of the aging environment has a significant impact on the hygroscopic behavior and mechanical properties of the composite,that is,the higher the temperature,the faster the moisture absorption of the composite,and the faster the decay of the mechanical properties of the composite.展开更多
文摘OBJECTIVE: Baby skin differs significantly from adult skin and requires special care. The Cussons Baby Sensicare Range (Sensicare) of products has been specifically formulated for baby skin and a range of standard cosmetic clinical tests were conducted in adult females with dry skin to evaluate the effectiveness of the range on skin moisturization and barrier function. METHODS: The studies were within subject, controlled, single blind studies. For the Sensicare Body Wash skin moisturization (Corneometer) was measured before application and after 7 and 14 days of twice daily use. For the Sensicare Moisturizing Lotion and Sensicare Soothing Cream skin moisturization was measured before application and at 2, 4, 6, 8 and 24 hours after a single application;skin elasticity (Cutometer) and transepidermal water loss (TEWL, Tewameter) were assessed before and after 14 days of twice daily use;and skin erythema (Mexameter) before induction with sodium lauryl sulphate (SLS), and at 30 mins, 24 and 48 hours after patch removal. Changes from baseline and changes versus control were evaluated. RESULTS: Thirty to thirty-five subjects completed each study. Skin moisture content was significantly increased from baseline for all Cussons Baby Sensicare Products (p < 0.05 for Hair & Body Wash;and p < 0.001 for Cream & Lotion). Changes from baseline in skin elasticity were significantly superior to control (unperfumed liquid soap) after 14 days twice daily use of the Lotion, and Cream (p < 0.05). There were no significant changes from baseline or significant differences from control in TEWL for the Lotion, or Cream. The increases in the average skin erythema index were significantly smaller for the Lotion, and Cream 30 minutes following SLS patch removal (p < 0.05 v sterile water, p < 0.001 v no treatment for both products). All the Sensicare products were well tolerated. CONCLUSION: These studies support the use of the Cussons Baby Sensicare range of products for new born, sensitive and eczema prone skin.
基金supported by the State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering(Grant No.SKLGDUEK2206)National Natural Science Foundation of China(Grant No.11872340).
文摘Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion discrete model that is capable of dynamically assessing the effect of cracking on moisture diffusion and allowing moisture to be discontinuous on both sides of the cracks.Then,the parametric analysis of the moisture exchange coefficient in the 3D moisture diffusion discrete model is carried out for moisture diffusion in continuous media,and the selection criterion of the moisture exchange coefficient for the unbroken cohesive element is given.Subsequently,an example of moisture migration in a medium with one crack is provided to illustrate the crack hindering effect on moisture migration.Finally,combining the 3D moisture diffusion discrete model with the finite-discrete element method(FDEM),the moisture diffusion-fracture coupling model is built to study the desiccation cracking in a strip soil and the crack pattern of a rectangular soil.The evolution of crack area and volume with moisture content is quantitatively analyzed.The modeling number and average width of cracks in the strip soil show a good consistency with the experimental results,and the crack pattern of the rectangular soil matches well with the existing numerical results,validating the coupled moisture diffusion-fracture model.Additionally,the parametric study of soil desiccation cracking is performed.The developed model offers a powerful tool for exploring soil desiccation cracking.
文摘This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked asphalt.Thermodynamic parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in self-healing.The results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing interface.Hydroxyl groups with different bonding states increase the interfacial adsorption capacity of water-soaked asphalt.The interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"phenomenon.The former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the components.Furthermore,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt.
基金supported by the National Natural Science Foundation of China [grant number 42088101]。
文摘During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.
基金The work described in this paper is partially supported by the Second Tibetan Plateau Scientific Expedition and Research Grant(2019QZKK0708)ARC Discovery Project grants(DP210100437,DP230100126),for which the authors are very grateful.
文摘The creep-slip behavior of creeping landslides is closely related to the creep characteristics of slope rock.This study analyzed the creep behavior of ultra-soft mudstone from the Gaomiao landslide in Haidong City,Qinghai Province,China.Uniaxial creep tests were carried out on ultra-soft mudstone with various moisture contents.The test results indicated that the creep duration of the rock sample with a natural moisture content of 9%is 2400 times longer than that of the sample with a natural moisture content of 13%,while its accumulated strain is 70%of the latter.For the rock sample with a natural moisture content of 9.80%,the creep duration under 0.5 MPa load is 80%of that under 0.25 MPa load,yet the accumulated strain is 1.4 times greater.Additionally,porosity significantly influences the creep behavior of mudstone.Analysis of the cause of the Gaomiao landslide and field monitoring data indicates that the instability of the Gaomiao landslide is related to the moisture content of the landslip mass and external forces.The creep-slip curves of landslides and the creep deformation curves of rocks share a common trend.Precisely identifying the moment when the shift occurs from steady state creep to accelerated creep is critical for comprehending slope instability and rock failure.Moreover,this study delves deeper into the issue of the consistency between landslide creep and rock deformation.
基金The authors would like to acknowledge financial support from the Joint Funds of the National Nature Science Foundation of China(No.U22A20232)Supported by Open Project Funding of Key Laboratory of Intelligent Health Perception and Ecological Restoration of Rivers and Lakes,Ministry of Education(HGKFZ07)+2 种基金the National Natural Science Foundation of China(No.51978249)Innovation Research Team Project of the Hubei Provincial Department of Science and Technology(JCZRQT202500027)the International Collaborative Research Fund for Young Scholars in the Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes.
文摘Plant root systems serve as a natural reinforcing material,significantly improving soil stability.Furthermore,the tensile strength of soil is crucial in mitigating the formation of cracks.Consequently,this study aims to investigate the influence of plant roots on the tensile strength of soil.For this investigation,Amorpha fruticose was selected due to its large root diameter and the ease of root extraction.Indoor tensile tests were conducted on individual roots and root-soil complexes under three varying factors.The results indicate a power law relationship between root diameter and tensile strength.Increased root content and dry density notably enhance the tensile strength of the root-soil complex while roots mitigate damage associated with soil brittleness.When root content increases from 0 to 10,the maximum enhancement in tensile strength of the root-soil complex reaches 42.3 kPa.The tensile strength of the root-soil complex at a dry density of 1.7 g/cm^(3)is four to five times greater than that of the complex at a dry density of 1.4 g/cm^(3).Moreover,as moisture content increases,the tensile strength of the root-soil complex initially rises before declining,with an increase range of 7.7-35.8 kPa.These findings provide a scientific basis for understanding the role of vegetation roots in soil tensile strength and for guiding slope reinforcement strategies.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004)National Natural Science Foundation of China(42475003)Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(SML2023SP209)。
文摘Southerly moisture surges over the central South China Sea(SCS)are characterized by the strengthening of lowlevel southerlies that transport moisture northward from the Pacific or Indian Oceans to South China.These surge events typically occur for days in the early-summer season(from April to June)and can lead to heavy rains in South China.This study categorizes surge events into three types of flow patterns and examines their multiscale variations and impacts on rainfall.The first type occurs mainly in April,with the southeasterlies enhanced by a deepening trough in South China and the western Pacific subtropical high established over the SCS.The second type of surge events mostly appears in June,featuring the prevailing southwesterlies of summer monsoon from the Indian Ocean during the active phases of intraseasonal oscillations.Most surge events exhibit semi-diurnal variations with morning and afternoon peaks of northward moisture fluxes.Specifically,the first type features a dominant afternoon peak,while the second type shows a dominant early-morning peak,which is induced by thermal contrast between the Indochina Peninsula and the SCS.In general,the surge events enhance moisture convergence and increase rainfall downstream in South China,but they show some regional differences.The second type strengthens moisture convergence and rainfall in coastal regions with a morning peak.In contrast,the first type enhances inland rainfall with a morning peak,while moisture divergence dominates coastal regions.The third type of surge events denotes transitional conditions between the first two types,in terms of atmospheric circulations,diurnal cycles,and rainfall patterns.These results highlight a diversity of regional moisture surges and related rainfall ranging from diurnal to sub-seasonal scales.
文摘This study investigates the potential of bamboo ash (CB) and sugarcane bagasse ash (CBCS) as sustainable filler and reinforcement materials to optimize the moisture resistance of bituminous concrete. The research addresses critical environmental and economic challenges by proposing the valorization of these agricultural by-products, which are rich in silica (SiO2) and possess pozzolanic properties, to improve the mechanical performance and durability of bituminous mixtures. Material characterization revealed the suitability of CB and CBCS due to their mineralogical composition and adherence to engineering standards for filler materials. Four formulations were tested, including a control sample and mixtures incorporating 0.2%, 0.3%, and 0.4% CB and CBCS. The mixture with 0.3% of each ash demonstrated optimal results, significantly enhancing Marshall stability, compactness, and fatigue resistance compared to the control sample. Durability assessments, including water sensitivity and freeze-thaw cycle tests, indicated superior performance of the modified mixtures, with reduced moisture-induced damage and enhanced resistance to extreme climatic conditions. Scanning Electron Microscopy (SEM) analyses confirmed improved microstructural integrity, showing strong adhesion between ash particles and the bitumen matrix, reduced porosity, and limited microcracking. In addition to mechanical and durability improvements, the integration of CB and CBCS offers substantial environmental and economic benefits. The study demonstrates a reduction in CO2 emissions and production costs, positioning these ashes as viable solutions for sustainable road construction. This research underscores the potential of incorporating agricultural by-products in bituminous concrete, achieving dual benefits: enhancing infrastructure durability and promoting sustainable resource utilization.
文摘The skin’s primary function is to protect the body against a spectrum of environmental stressors, including mechanical insults, microorganisms, chemicals, and allergens. Located in the outermost layers, the primary structures and components responsible for the skin’s barrier function are susceptible to environmental variables, dermatological conditions, and the aging process. The ensuing alterations to structure, composition, and organizational attributes of the epidermal barrier can impact its integrity and functionality. The aim of this study was to assess the effect of a novel complex composed of a ceramide, energizing peptide, and Camu Camu extract (SUPCERAT<sup>TM</sup> complex) on specific markers of epidermal barrier integrity, as well as epidermal and dermal function. All the experiments were conducted on fresh human abdominal skin explants. Intradermal production of hyaluronic acid, epidermal claudin-1, and ceramide synthase 3 expressions, as well as epidermal lipids content were assessed using specific fluorescent stainings on ex vivo skin after the application of the complex or placebo. Additionally, dermal elastase and collagenase activities were assessed using in tubo enzymatic assays. Lastly, the effect of a cosmetic cream containing SUPCERAT<sup>TM</sup> complex was assessed using subjective Global Aesthetic Improvement Scale (GAIS) in a small cohort of patients after 60 days of use. The application of the SUPCERAT<sup>TM</sup> complex on ex vivo skin led to significant increase in dermal hyaluronic acid content and epidermal activity of claudin-1, ceramide synthase 3 and epidermal ceramide content. Furthermore, in tubo enzymatic assays demonstrated inhibition of both dermal elastase and collagenase activities. In addition, the patient-reported results indicated significant improvements in skin quality and appearance. .
基金supported by the National Centre for Atmospheric Science through the NERC National Capability International Programmes Award (NE/ X006263/1)the Global Challenges Research Fund, via Atmospheric hazard in developing Countries: Risk assessment and Early Warning (ACREW) (NE/R000034/1)the Natural Environmental Research Council and the Department for Foreign International Development through the Sat WIN-ALERT project (NE/ R014116/1)。
文摘Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa.
基金supported by the Natural Science Foundation of China(Grant Nos.42088101 and 42205149)Zhongwang WEI was supported by the Natural Science Foundation of China(Grant No.42075158)+1 种基金Wei SHANGGUAN was supported by the Natural Science Foundation of China(Grant No.41975122)Yonggen ZHANG was supported by the National Natural Science Foundation of Tianjin(Grant No.20JCQNJC01660).
文摘Accurate soil moisture(SM)prediction is critical for understanding hydrological processes.Physics-based(PB)models exhibit large uncertainties in SM predictions arising from uncertain parameterizations and insufficient representation of land-surface processes.In addition to PB models,deep learning(DL)models have been widely used in SM predictions recently.However,few pure DL models have notably high success rates due to lacking physical information.Thus,we developed hybrid models to effectively integrate the outputs of PB models into DL models to improve SM predictions.To this end,we first developed a hybrid model based on the attention mechanism to take advantage of PB models at each forecast time scale(attention model).We further built an ensemble model that combined the advantages of different hybrid schemes(ensemble model).We utilized SM forecasts from the Global Forecast System to enhance the convolutional long short-term memory(ConvLSTM)model for 1–16 days of SM predictions.The performances of the proposed hybrid models were investigated and compared with two existing hybrid models.The results showed that the attention model could leverage benefits of PB models and achieved the best predictability of drought events among the different hybrid models.Moreover,the ensemble model performed best among all hybrid models at all forecast time scales and different soil conditions.It is highlighted that the ensemble model outperformed the pure DL model over 79.5%of in situ stations for 16-day predictions.These findings suggest that our proposed hybrid models can adequately exploit the benefits of PB model outputs to aid DL models in making SM predictions.
基金supported by the National Key R&D Program of China(Grant No.2022YFF0801603).
文摘The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July 2020.This unique long-lasting extreme event and its origin have attracted considerable attention.Previous studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected event.However,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain unclear.By using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in 2020.Results show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST backgrounds.The intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒July.The intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 mei-yu.In contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil moisture.The roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System Model.Their synergistic impacts yield a notable 32%increase in YRB precipitation.Our findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.
基金funded by the National Natural Science Foundation of China (No. 42172308, No.51779018)the Youth Innovation Promotion Association CAS (No. 2022331)the Science and Technology Research and Development Program of China State Railway Group Co., Ltd. (No. J2022G002)。
文摘Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various excavation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks expedite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack expansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are explored. The number of tensile and shear cracks increases with greater excavation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways.
基金funded by Taif University,Taif,Saudi Arabia(TU-DSPP-2024-172).
文摘In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture diffusivity.The problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic waves.The study examines the photothermoelasticity transport process while considering the impact of moisture diffusivity.By employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic medium.These equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive relationships.Mechanical stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace domain.By employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under study.Referencemoisture,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.
文摘Erratum to:J.Mt.Sci.(2024)21(5):1663-1682 https://doi.org/10.1007/s11629-023-8561-0 During the production process,the first author’s name was wrongly written as“Rang Huang”in the metadata.The correct name for the first author is“Kang Huang”.The first author’s name in the fulltext pdf is correct.
基金supported by a Guangdong Major Project of Basic and Applied Basic Research (Grant No.2020B0301030004)the Collaborative Observation and Multisource Real-time Data Fusion and Analysis Technology & Innovation team (Grant No.GRMCTD202103)the Foshan Special Project on Science and Technology in Social Field (Grant No.2120001008761)。
文摘Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation.
基金The National Natural Science Foundation of China under contract Nos 41830536 and 41925027the Guangdong Natural Science Foundation under contract No.2023A1515011235the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)under contract No.311021008.
文摘The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer data.This SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice temperature.The relationship between the SIT and PR was found to be almost stable across the five selected regions.The SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction sensors.The results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT data.The proposed algorithm can be used for thin sea ice thickness(<1.0 m)estimation in the Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.
基金This study was supported by the National Natural Science Foundation of China(42261008,41971034)the Natural Science Foundation of Gansu Province,China(22JR5RA074).
文摘Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,which affects the accuracy of local moisture recycling.In this study,a total of 18 stations from four typical areas in China were selected to compare the performance of isotope-based linear and Bayesian mixing models and to determine local moisture recycling ratio.Among the three vapor sources including advection,transpiration,and surface evaporation,the advection vapor usually played a dominant role,and the contribution of surface evaporation was less than that of transpiration.When the abnormal values were ignored,the arithmetic averages of differences between isotope-based linear and the Bayesian mixing models were 0.9%for transpiration,0.2%for surface evaporation,and–1.1%for advection,respectively,and the medians were 0.5%,0.2%,and–0.8%,respectively.The importance of transpiration was slightly less for most cases when the Bayesian mixing model was applied,and the contribution of advection was relatively larger.The Bayesian mixing model was found to perform better in determining an efficient solution since linear model sometimes resulted in negative contribution ratios.Sensitivity test with two isotope scenarios indicated that the Bayesian model had a relatively low sensitivity to the changes in isotope input,and it was important to accurately estimate the isotopes in precipitation vapor.Generally,the Bayesian mixing model should be recommended instead of a linear model.The findings are useful for understanding the performance of isotope-based linear and Bayesian mixing models under various climate backgrounds.
基金supported by National Natural Science Foundation of China(No.22278308,22109114 and 22102099)。
文摘Lithium hexafluorophosphate(LiPF_(6)),the most commonly used lithium battery electrolyte salt,is vulnerable to heat and humidity.Quantitative and qualitative determination the variation of LiPF_(6)have always relied on advanced equipment.Herein,we develop a fast,convenient,high-selective fluorescence detection method based on metal-organic cages(MOC),whose emission is enhanced by nearly 20 times in the presence of LiPF_(6)with good stability and photobleaching resistance.The fluorescent probe can also detect moisture in battery electrolyte.We propose and verify that the luminescence enhancement is due to the presence of hydrogen bond-induced enhanced emission effect in cages.Fluorescent excitation-emission matrix spectra and variable-temperature nuclear magnetic resonance spectroscopy are employed to clarify the role of hydrogen bonds in vip-loaded cages.Density functional theory(DFT)calculation is applied to simulate the structure of host-vip complexes and estimate the adsorption energy involved in the system.The precisely matched lock-and-key model paves a new way for designing and fabricating novel host structures,enabling specific recognition of other target compounds.
文摘In order to explore the effect of artificial accelerated aging temperature on the performance of carbon fiber/epoxy resin composites,we used artificial seawater as the aging medium,designed the aging environment of seawater at different temperatures under normal pressure,and studied the aging behavior of carbon fiber/epoxy composites.The infrared spectroscopy results show that,with the increase of aging temperature,the degree of hydrolysis of the composite is greater.At the same time,after 250 days of aging of artificial seawater at regular temperature,40 and 60 ℃,the moisture absorption rates of composite materials were 0.45%,0.63%,and 1.05%,and the retention rates of interlaminar shear strength were 91%,78%,and 62%,respectively.It is shown that the temperature of the aging environment has a significant impact on the hygroscopic behavior and mechanical properties of the composite,that is,the higher the temperature,the faster the moisture absorption of the composite,and the faster the decay of the mechanical properties of the composite.
