Moisture Time Research Articles

Study on the Effect of Dry and Wet Cycle Time Ratio on the Corrosion Behavior of 2198 Aluminum–Lithium Alloy

ABSTRACTThe corrosion of 2198 aluminum–lithium alloy in a marine atmospheric environment was simulated using a wet–dry alternating experimental setup. Weight‐loss measurement methods, electrochemical impedance spectroscopy (EIS), scanning electron microscopy/energy‐dispersive spectroscopy (SEM/EDS), macroscopic morphology testing, three‐dimensional morphology testing, and X‐ray photoelectron spectroscopy (XPS) were used to study the wet–dry alternating corrosion behaviors and mechanisms of 2198 aluminum–lithium alloys under simulated marine atmospheric environment. The results indicate that corrosion weight loss increases with decreasing wet‐to‐dry ratios, accompanied by an increase in the corrosion rate. Various data suggest that the primary corrosion products are composed of Al2O3, AlO(OH), and AlCl3. The reduction in the wet‐to‐dry ratio leads to the enrichment of Cl⁻ within the corrosion products, extending the contact time between the substrate and the medium, thereby intensifying the hydrolysis of Al³⁺. This exacerbates the dissolution at pitting sites, which in turn erodes and breaks down the corrosion product film, accelerating the overall corrosion process.

Appropriate Terminology for the Time Elapsed From Avulsion of a Permanent Tooth to Replantation: A Scoping Review and Delphi Consensus.

The prognosis of an avulsed permanent tooth depends on the time elapsed from injury to replantation in the injured socket. Wide variability exists in the terminologies used to describe this period. Hence, the aim of this study was to identify and categorize the terminologies related to this aspect of tooth avulsion, grade the explanations provided by the authors, and develop a consensus about the most appropriate terminology through a Delphi approach. This study involved a scoping review to identify and analyze the terminologies. It was performed according to PRISMA-ScR with a systematic search performed in PubMed, Scopus, EMBASE, LILACS, and Web of Science. The terminologies were extracted, categorized, and evaluated for correctness. On the basis of the results of the review and expert group discussion, an ideal terminology was proposed. A Delphi study with 20 global experts in dental traumatology was conducted to develop a consensus for the proposed terminology and its description. A total of 92 studies were included. They were distributed into five categories according to the terminology used: (a) dry period alone, (b) total period with dry and/or wet times, (c) extra-alveolar period, (d) extraoral period, and (e) miscellaneous. The explanations provided were correct in 37.5% of the studies that used an extraoral period. In the Delphi study, the lowest scores were given to the term dry period. There was an agreement of 95% for the proposed terminology. A wide variation in terminologies was observed that could be distributed into five categories. The correctness of explanations was highest in the studies that described total periods with dry and wet times. The Delphi study revealed excellent agreement for the proposed term "total extra-alveolar period," with precise and clear recordings of both nonphysiologic (dry) periods and physiologic (wet) periods.

The effect of variable humidity on corrosion fatigue of AA7085-T7451 with surface salt deposits

Corrosion fatigue (CF) crack growth is quantified as a function of relative humidity (RH) using AA7085-T7451 samples with NaCl deposited to understand the effect of deliquesced surface electrolyte droplets on CF performance when humidity varies. Fracture mechanics testing holding mechanical driving forces for cracking constant and incrementally increasing humidity show that crack growth rate (da/dN) more than doubles once RH moves above 78–80% RH. When decreasing RH, some amount of drying below the efflorescence RH (ERH) and/or a sufficient time is needed to pass in order for da/dN to return to that expected for a dry crack tip. All in all, this study establishes time of crack tip wetness as an important parameter for predicting fatigue lifetimes in atmospheric conditions, a parameter that cannot be solely predicted by RH, as accelerated cracking can continue for a limited amount of time even when RH is brought below the ERH.

Mp[fgForecasting rainfall events based on zenith wet delay time series utilizing eXtreme Gradient Boosting (XGBoost)

Mp[fgForecasting rainfall events based on zenith wet delay time series utilizing eXtreme Gradient Boosting (XGBoost)

Development and Assessment of Loratadine Fast-Disintegrating Tablets via β-Cyclodextrin Complexation with Superdisintegrants

ABSTRACT: This study aimed to enhance the solubility and consequent bioavailability of Loratadine, a widely used medication for seasonal allergic rhinitis and chronic idiopathic urticaria. The approach involved complexation with β-cyclodextrin to improve solubility and the formulation of fast-disintegrating tablets via the sublimation method. Crosspovidone acted as a superdisintegrant, while camphor served as a sublimating agent. Methodology: Pre-compression parameters were assessed to ensure adequate flow properties, while post-compression parameters were evaluated against IP acceptable limits for variations in hardness, weight, wetting time, friability, drug release, and disintegration time, drug content, FTIR, and DSC. Dissolution studies were conducted in 0.1N HCL, and statistical analysis employed a central composite design for optimization. Results: Formulation B14 emerged as the optimized batch, demonstrating favourable characteristics including wetting time, in vitro drug release, drug content, and disintegration time. Analysis of stability conducted in accordance with ICH guidelines affirmed the formulations' stability. Conclusion: The developed fast-disintegrating tablet formulation of Loratadine exhibited enhanced solubility, potentially translating to improved bioavailability. These advancements suggest increase efficacy and improved patient compliance in the management of allergic rhinitis and urticaria.

Valorisation of sodium lignosulfonate from wood pulping industries for the enhancement of moisture management properties of nylon fabric

Nylon fabric has poor moisture management properties due to the absence of hydroxyl groups. In this work, an attempt has been made to enhance the moisture management properties of nylon fabric using sodium lignosulfonate (SLS). SLS is an essential by-product of the wood pulping industry. Various concentrations of the SLS were prepared in an aqueous medium, and the nylon fabric was treated with them using the exhaust method. The effects of the parameters of the treatment process are analyzed using Box–Behnken response surface design of experiment and analysis of variance (ANOVA). Upon testing the water vapour transmittance rate (WVTR), it was found that the SLS treatment is efficacious in improving moisture management. Water contact angle is reduced to 10.6° from 105.3° after the coating, which proves the achievement of hydrophilic surface. The average wetting time of nylon fabrics decreased by 78% after the SLS treatment. A significant increase in the bending modulus, flexural rigidity, and coefficient of the SLS-treated fabrics is observed when SLS concentration is high. After the SLS treatment, wetting time decreases, absorption rate increases, spreading speed increases, and overall moisture management capacity (OMMC) increases significantly. The SLS coating over the nylon surface is found to be durable with excellent rating for light and washing fastness.

Development of a Reliable Accelerated Corrosion Test for Painted Aluminum Alloys Used in the Aerospace Industry

New environmental regulations have led to major changes in aluminum corrosion protection by prohibiting, for example, Cr(VI). Thus, the assessment of the corrosion behavior of Cr-free systems under atmospheric conditions is a major topic of interest for the aerospace industry. One major difficulty in this task is the lack of robust and reliable accelerated corrosion test(s) in this field. The aim of the present study is to compare the results of various accelerated corrosion standards (ASTM B117, ISO 4623-2, VCS 1027,149) to results obtained after 5 years of exposure at a marine atmospheric site in Brest, France. Additional accelerated corrosion tests were designed by varying several parameters in the VCS 1027, 149, such as the salt concentration, the time of wetness, and the relative humidity. The different modes of failure obtained in accelerated corrosion tests on the painted samples were then compared to field exposures in a marine atmospheric site. The first results obtained showed that the developed tests are more representative of service conditions than standard tests.

Anisotropic growth of Ag nanonails induced by plasmon-mediated chemical reactions in cross-shaped nanocavity array

The Ag nanonail rooted in Au cross-channel nanocavity is fabricated by plasmon-mediated chemical reactions (PMCRs). The Au cross-channel nanocavity is prepared based on two-dimensional polystyrene (PS) nanosphere template through wet etching, and the shape of Au cross-channel nanocavity changes from trapezoidal to triangular, depending on the wet etching time. The growth of Ag nanostructures in Au channels by PMCRs indicates the morphology of Ag nanostructures has changed from Ag nanoparticles to nanonails, which is regulated by the shape of Au nanocavities and the exciting light polarization. The hotspots distributions results in the anisotropic growth of Ag nanostructures induced by PMCRs, which leading to the different Ag nanostructures depending on the shape of Au nanocavity and light polarization, as confirmed by FDTD simulations. In comparison with others reports, our nanocavity provide more parameters to control the shapes of Ag nanostructures, the nanocavity shape, the light polarization and the growth time. Our work provides a profound insight into the construction of periodic nanostructures and reconstruction of hotspots.

Atmospheric corrosion and mechanical property degradation of 2524-T3 aluminum alloy in marine environments

Atmospheric corrosion and the resulting mechanical property degradation of 2524-T3 aluminum alloy in marine environments with different environmental factors are investigated. 2524-T3 aluminum alloy exhibits the most severe corrosion in tropical marine atmosphere, attributed to the highest temperature, humidity, rainfall, Cl- deposition rate, and the longest time of wetness. The EIS results are closely related to the corrosion evolution process. The degradation sensitivity indexed by elongation, reduction-in-area, and tensile strength is correlated with the average corrosion-induced surface defect depth (D′ave), while the elasticity modulus is related to the maximum corrosion penetration depth (Dmax).

Dissolved organic carbon (DOC) and labile organic compounds' spatial and temporal variations in coastal Indian groundwater: their bioavailability and transfer to neighboring coastal waters of India.

Submarine groundwater drainage (SGD) changes the elemental composition of the neighboring coastal ocean and impacts the biogeochemical cycles. To examine the seasonal and spatial variability in dissolved organic carbon (DOC) and labile organic compound biochemical compounds like dissolved carbohydrates (TDCHO), dissolved proteins (TDPRO), and dissolved free amino acid (TDFAA) concentrations during the dry and wet periods, groundwater samples were taken at 90 locations (180 samples) along the Indian coast. The mean DOC contents in Indian coastal groundwaters were more significant than the global mean values. DOC, TDCHO, TDPRO, and TDFAA concentrations are higher during wet than dry periods. The DOC and labile organic compound showed a substantial positive association with soil organic carbon, and respective labile compounds in soil, population, and land usage and poor relation with woodland territories, implying that soil organic compounds leaching is a source of DOC and other labile organic compounds into the groundwater. DOC and other labile compounds concentrations were linearly associated with population density, land usage, and sewage production, demonstrating that anthropogenic activities tightly regulate the formation of DOC in groundwater. During the wet and dry periods, total labile organic compounds (TDCHO, TDFAA, and TDPRO) constituted 21% and 10.5% of DOC, respectively. Compared to the wet time, more aromatic compounds accumulated during the dry season but were less bioavailable. SGD DOC flux contributed 2-7% of riverine DOC flux to the coastal ocean. The SGD flux from the Indian subcontinent to the nearby northern Indian Ocean accounts for approximately 2% of the worldwide SGD flux. The effect of DOC flux via SGD on coastal bacterial activity, the plankton food web, and the oxygen minimum zone must be studied.

Water transport and corrosion under insulation: Experimental investigations of drying in mineral wool

Corrosion under insulation (CUI) is a major risk factor for the material integrity of insulated equipment that is encountered i.a. in the chemical process industries. Undetected CUI has been the root cause for major accidents, including loss-of-site, loss-of-life, prolonged plant shutdown, and environmental pollution. Reducing CUI risk via labour-intensive inspection routines is associated with billions of dollars of annual maintenance costs worldwide. CUI is caused by water bypassing a weather shield, migrating through the insulation and contacting the equipment surface. The resulting corrosion rates are very high and the process is hidden from view. Surprisingly, the fundamental mechanisms that drive water migration through insulation have been largely unexplored. In this work we present novel experimental investigations of the evaporation and drying dynamics for a heated vertical pipe with preformed mineral wool insulation and metal cladding. Relative humidity and temperature sensors provide measurements of how the water evaporates and travels through the system during controlled water ingress experiments. The experimental data shows that the drying time of the insulation material is proportional to the amount of water added. We find that the drying process proceeds in two stages, where the length of the first drying regime is directly related to the diffusion-limited evaporation from the bulk liquid water, while the second drying time is influenced also by other factors such as the adsorption and desorption of water on the insulation material fibres. The findings have implications for how time of wetness, used in CUI risk-based inspection methods, can be obtained from humidity sensor data. The new insights into water transport in insulation enables a paradigm shift towards predictive CUI maintenance using humidity spot sensors.

Effects of poly‐γ‐glutamic acid addition on the transformation and distribution of soil nitrogen under different water conditions

AbstractThe impact of external poly‐γ‐glutamic acid (γ‐PGA) on soil nitrogen (N) transformation and distribution remains unclear, despite its contrasting effects on N use efficiency. Therefore, soil culture and soil column experiments were conducted using three different γ‐PGA addition rates (0%, 4% and 8% of dry soil weight, w/w) under different soil water contents (40%, 60% and 80% of field water capacity) and dry–wet cycles (0, 2, 4 and 8 times cycles; a single dry–wet cycle involved reducing soil water content from 80% to 40% of field water capacity) in sandy loam soil. The results of soil culture experiment showed that the γ‐PGA significantly increased soil –N and –N contents, as well as nitrification and transformation rates. However, these effects were observed to be influenced by both the culture time and soil water content. In addition, the results of soil column experiment showed that γ‐PGA not only significantly enhanced the soil inorganic nitrogen content within the 0–20 cm soil layer, but also improved water retention capacity. However, the differences between the γ‐PGA treatments gradually diminished with an increase in dry–wet cycle times. These results indicate that γ‐PGA addition enhanced soil inorganic N content and soil water retention by influencing soil N transformation and water distribution. However, the impact of γ‐PGA addition on soil improvement was regulated by soil water content, which should be taken into full consideration in agricultural practices.

Comparative study of fiber materials for enhanced performance of hybrid cooling in battery thermal management systems

Battery thermal management systems play a crucial role in maintaining the optimal temperature range of lithium-ion batteries, ensuring their efficient operation and prolonged lifespan. Hybrid cooling (HC) techniques, which involve the utilization of hydrophilic fibers, have shown promise in enhancing the thermal performance of these systems. The present study employs an experimental approach to investigate the impact of selected fiber materials on the thermal performance of a hybrid cooling system designed for battery thermal management. Parameters such as the time required for complete wetting of the fiber and the coolant absorption capacity of the fiber are considered during the fiber selection process. Findings reveal that the tissue paper fiber displayed superior water transfer capabilities, achieving a minimum wetting time of 46 s for a 75 mm fiber length. This characteristic positions it as a promising candidate for the subsequent hybrid cooling experiment. Noteworthy is its water holding capacity per unit volume, which surpassed that of cotton fiber by 40%. HC demonstrates the superior temperature uniformity and average battery pack temperature compared to simple air cooling (SAC) under varying velocities, emphasizing the pivotal role of HC. A remarkable improvement of 41.86% in temperature uniformity is obtained in HC over SAC.

Sustainable scouring of cotton using extracts from wood ash and soapnut and its optimisation by response surface methodology

AbstractThe non‐cellulosic impurities like oil, wax, and pectins present in the cotton fibre adversely impact wetting. Consequently, these impurities must be removed during the pretreatment process to prevent unevenness of subsequent coloration. Generally, an alkaline treatment with petroleum‐based synthetic surfactants is done, which is called scouring. This study attempts to develop an environmentally safe alternative using alkali from wood ash extract (WAE) and surfactant from soapnut extract (SE). The factors of WAE (10%–30%), SE (5–15 g/L), temperature (75–95°C), and time (20–60 min) were optimised using response surface methodology. A concentration of 20% WAE and 10 g/L SE at 90°C for 30 min was found to be adequate to remove impurities. The statistically optimised method showed good hydrophilicity, indicated by an average wetting time of 15 s, and 2.7% weight loss. The scoured fabric was subsequently dyed with natural dye extracted from marigold flowers and reactive dye. The scoured cotton was evaluated by weight loss, wettability, tensile strength, whiteness index, and colour value (K/S) and showed comparable results to conventional scouring.

Viscoelastic–plastic rheological model and its application to tunnels

Tunnels exhibit obvious continuous deformation during excavation and operation. This behaviour is closely associated with the time-dependent behaviour of rocks, which is induced by groundwater-level fluctuation and prolonged periodic rainfall infiltration. This paper proposes a rheological model consisting of a Hooke elastomer, Kelvin body and novel plastic element in series (called the HKP model) to describe the creep response of rocks considering the characteristics of dry–wet cycles. First, dry–wet cycle creep tests were carried out to investigate the time-dependent behaviour: that is, the creep behaviour of sandstone. Then the creep equation of the viscoelastic–plastic model was derived, and the damage coefficients under the effect of dry–wet cycles and time were obtained. Finally, the HKP model was established to investigate continuous deformation during tunnel excavation. The results reveal that dry–wet cycles have obvious effects on the physical properties and creep behaviour of sandstone. The creep behaviour of sandstone undergoes three stages – namely, the decaying, steady and accelerated stages – that can be reasonably described by the proposed HKP model. In practice, the proposed model can accurately predict the creep behaviour of rocks in tunnels owing to excavation. Thus, the HKP model can help in establishing tunnel maintenance strategies to ensure long-term safety.

IN SILICO AND IN VITRO EVALUATION OF SILK FIBROIN BASED AMORPHOUS BALL-MILLED BINARY SOLID DISPERSION FOR IMPROVED SOLUBILITY, DISSOLUTION AND TABLETTABILITY: THE CASE OF NAPROXEN

The present study aims to use a natural protein silk fibroin (SF) to enhance solubility, dissolution, tablettability, and subsequently, delivery of naproxen (NP) using a green technique  ball milling. The development of SF and NP solid dispersion (SF-NP-SD) for enhancing the solubility, dissolution, and compatibility of NP using ball milling. In silico molecular docking indicated a strong binding affinity of SF towards NP. Herein, SF-NP-SD (1:1) showed significant improvement (p 0.05) in saturation solubility (12 fold) and dissolution (1.46 fold) of NP. Along with reduced wetting time (p 0.05), optimum values of flowability, compressibility, and compatibility were noteworthy. The spectroscopic analysis confirmed favorable interactions, amorphization, and stabilization of NP. The tablet formulation of SF-NP-SD exhibited 1.38-fold enhanced dissolution. Molecular-level hydrophobic and hydrophilic interactions of SF favor molecular-level dispersion, enhance solubility and dissolution, and consecutively, improve drug delivery of NP.

Optimizing ventilated packaging design for strawberries: Assessing the impact on fruit quality from farm to retailer using physics-based modeling

Amongst fruits and vegetables, strawberries (Fragaria × ananassa) are one of the most perishable products. Consequently, it is challenging to maintain their quality until they reach the consumer. Therefore, keeping optimal hygrothermal conditions around the berries from farm to the consumer is crucial to preserving them and avoiding food loss. Using ventilated packaging design is an established way to address this technological, economic, and environmental problem. Until now, strawberry packaging is often designed using a trial-and-error approach, and a multitude of packaging designs exist. Ideally, the packaging should be designed in such a way that it provides the best preservation of the fruit all the way from farm to retailer. This is challenging since the hygrothermal conditions change significantly along the supply chain. In this study, we use physics-based modeling to evaluate new strawberry packaging designs in regard to cooling performance, risk of condensation, mass loss, and respiration-driven shelf life of the fruit and assess their performance along the whole post-harvest export supply chain from Spain to Switzerland. Twelve packaging designs for strawberries with existing and newly-designed vent hole configurations were investigated. Simulations quantified how the berries physiologically and hygrothermally evolve inside these packages along the whole post-harvest supply chain. Implementing appropriate ventilation in open-and top-sealed trays for strawberries can help to minimize losses along the post-harvest supply chain. As commonly known, strawberries cool significantly faster in better-ventilated trays than in unventilated trays, and condensation-based time of wetness could be reduced by 45% by adding additional ventilation holes in a top-sealed tray. The height of the secondary packaging, the total opening area (TOA), the size, and the placement of the vents have a substantial influence on the performance of the packaging. We recommend a TOA between 5.5% and 7% and a diameter of the vents between 5 and 12 mm. Also, they should be evenly distributed. However, there is always a trade-off in packaging design: a reduced risk of condensation comes along with a higher mass loss of the strawberries. Strawberry packaging models enabled a unique insight into the evolution of the fruits along the supply chain and visualized the spatial distribution of condensation and mass loss inside the package.

The influence of cyclodextrin on hydrophobicity of pipeline and asphalt distribution: A green and efficient corrosion inhibitor

Corrosion inhibitors face significant limitations due to their non-degradability and poor applicability to asphalt systems. The molecular simulation studies show that cyclodextrin (CD) and asphalt can form supramolecular corrosion inhibitors with pipeline hydrophobic modification and corrosion inhibition effects. In particular, the rich hydroxyl structure of CD enables it to stably bind to the pipeline by forming coordination bonds and feedback bonds. When 2 CD molecules are added, the initial wetting time of the emulsion is delayed by 257.81 % compared to Span 80 with the same mass fraction. When 4 CD molecules are added, the emulsion cannot wet the iron surface within the simulation time. Furthermore, the combination of CD and asphalt allows more than 90 % of the asphalt to emulsify and prevent the emulsion from spreading on the pipeline. This results in a synergistic corrosion inhibition effect. These findings suggest that CD-based supramolecular corrosion inhibitors have the potential to be effective and environmentally friendly alternatives to traditional inhibitors in asphalt systems.

Formulation and optimization of electrospun nanofiber films for ultrafast delivery of domperidone: In vitro and in-vivo characterization

Nanotechnology has significantly transformed drug delivery approaches by providing precise control of drug release kinetics and enhancing therapeutic effectiveness. Electrospun nanofiber films have unique features, including a significant surface-to-volume ratio and substantial porosity, resulting in enhanced patient adherence. The study was aimed at developing electrospun nanofiber films of domperidone for ultrafast release using polyvinyl alcohol (PVA). The nanofibers were prepared by electrospinning method and optimized using 32 factorial design. Electrospinning process parameters like feed rate, applied electric voltage, and tip-to-collector distance were optimized. The prepared nanofiber film was characterized using scanning electron microscopy, differential scanning calorimetry (DSC), Fourier transform infrared microscopy (FTIR), X ray diffraction (XRD), in-vitro diffusion, and permeation studies. The resultant domperidone-loaded nanofibers (diameters 280–565 nm) exhibited a uniform and highly porous structure. With an increase in applied voltage from 11 to 13 kV, entrapment efficiency increased, and fiber diameter decreased. DSC and XRD results confirmed the amorphous nature of the domperidone. The FTIR study confirmed the compatibility between domperidone and PVA. The wetting and disintegration times of nanofibers were 8 and 4 s, respectively. Due to their nanosize, small particles with an increased surface area resulted in improved drug delivery through nanofibers (93.36% release within 10 min). The nanofiber film had a higher Cmax (398.8 ng/mL) and AUC (2078.593 ± 17.71 ng/mL.h) than the commercial tablet formulation (186.6 ng/mL and 1875.619 ± 10.38). Thus, domperidone nanofibers would be a promising approach for enhancing therapeutic and biopharmaceutical properties by providing ultra-fast delivery.

Atmospheric corrosion of carbon steel: Results of one-year exposure in an andean tropical atmosphere in Colombia

In this study was examined the response of carbon steel to atmospheric corrosion after one-year exposure in Valle de Aburrá, a subregion located in northwestern Colombia. The study involved the assessment of material mass loss and corrosion rate, the characterization of atmospheric aggressiveness, and the analysis of the morphology and composition of corrosion products in five different sites. Climatological and meteorological factors were assessed by testing for chloride content, sulfur dioxide levels, and time of wetness (TOW). The analysis of corrosion products was conducted using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. Based on corrosion rates, two sites exhibited a more aggressive environment, with a corrosivity category of C3, while the remaining sites were categorized as C2. The study confirmed the presence of lepidocrocite and goethite phases on the surface of carbon steel at all test sites. Data analysis revealed that both the TOW and the industrial activity significantly influence the corrosion of this metal.