Humid Environment Research Articles

Climate Conundrum: A Wet or Dry European and Northern African Climate During the Middle Miocene

AbstractEnd of 21st‐century hydroclimate projections suggest an expansion of subtropical dry zones, with Mediterranean and Sahel regions becoming much drier. However, paleobotanical assemblage evidence from the middle Miocene (17‐12 Ma), suggests both regions were instead humid environments. Here we show that by modifying regional sea surface temperatures (SST) in an Earth System Model (CESM1.2) simulation of the middle Miocene, the increased ocean evaporation and integrated water vapor flux overrides any drying effects associated with warming‐induced land‐surface evaporation driven by atmospheric CO2 concentrations. These modifications markedly reduce the bias in the model‐data comparison for this period. A vegetation model (BIOME4) forced with simulated climatologies predicts both regions were dominated by mixed forest, which is largely consistent with the paleobotanical record. This study unveils the potential for wetter subtropical Mediterranean climates associated with warming, presenting an alternative scenario from future drying projections with localized SST warming governing regional climate change.

Enhancing Ozone Decomposition in Humid Environments through Carbon Doping to Disrupt the Hydrogen Bond Network in Mullite YMn2O5.

The strong adsorption of water molecules at the active site of the catalyst presents significant challenges in ozone decomposition, particularly at room temperature and in humid environments. To address this issue, we doped carbon atoms into the Mn-mullite YMn2O5 catalyst to replace oxygen, resulting in efficient and stable ozone decomposition under highly humid conditions. Utilizing DFT calculations, our study demonstrated that carbon doping disrupts hydrogen bond networks on the catalyst surface, thereby reducing water adsorption. Furthermore, carbon doping regulated the electronic structure of active sites, fundamentally reversing the adsorption strength of water and ozone molecules, which avoids the decline in catalytic activity caused by competitive water adsorption. Experimentally, under room temperature and relative humidity (RH) 50%, the carbon-doped YMn2O5 catalyst maintained 100% conversion in decomposing 100 ppm of ozone for at least 24 h, surpassing the most reported catalysts against water poisoning. Furthermore, the utilization of a carbon-doped mullite-loaded air cleaner demonstrated promising application in degrading ozone. The approach of enhancing catalyst water resistance through carbon doping, which disrupts hydrogen bonds, provided valuable insights into the design of stable and efficient room-temperature ozonolysis catalysts.

Environmentally Friendly MoS2-hBN Solid Lubricants: A Comprehensive Tribological Evaluation

Abstract MoS2-based solid lubricants have obtained significant attention and are extensively employed in the aerospace industry due to their desirable tribological performance. However, to enhance their performance in humid environments, MoS2 is often doped with Pb-based compounds. Considering the health and environmental concerns associated with Pb, it is necessary to develop eco-friendly alternatives. In this study, hexagonal boron nitride (hBN) has been used as a potential substitute for Pb-based dopants in MoS2-based solid lubricants and coatings with varying hBN contents (9.5, 11.5, 13.5, 15.5, and 17.5 wt%) were applied to stainless-steel substrates using a spray bonding technique. The friction and wear characteristics of the coatings were analyzed by using a ball-on-flat tribometer, employing constant load conditions. Subsequently, ex situ analysis techniques such as scanning electron microscopy, Raman spectroscopy, and atomic force microscopy were used to characterize the coatings. The results showed that the coating with a lower hBN concentration presented improved tribological properties, which was correlated with the development of an effective MoS2-based transfer/tribo-film. This suggests that optimizing hBN content is crucial for enhancing the lubrication performance.

Enhancing the quality of wholemeal bread with chia, sesame, and rosehip: mathematical modelling and organoleptic analysis

In this paper, the research was conducted using mathematical modelling methods to improve the quality of the product. This study aimed to determine the optimum composite mixture for producing whole wheat flour by adding sesame seeds, chia seeds, and crushed rosehip. Following the mathematical matrix, 20 different samples have been baked. The basic criteria were porosity and specific volume. The results were entered into Exel to draw up a graph. According to the graphic analysis, the most optimal mixture in terms of the dry matter mass in the dough was as follows in %: rosehip - 1.1%, chia seeds - 1.5%, and sesame - 2.2%. The organoleptic and physicochemical properties of the resulting samples were later analysed according to the recipes based on the selected composition of seeds. By swelling the protein shells of chia and sesame in a humid environment, amino acids in the flour combine into a chain to form a skeleton. At the same time, the ascorbic acid in the rosehip binds with the carbon atoms in the chain, strengthening the framework. As a result, large amounts of gases formed in whole grain flours are trapped in these frames, increasing the porosity of bread by 21.8%, increasing the volume of production by 29.5%, absorbing proteolytic enzymes under the influence of globulins in chia grain, slowing down amino acid degradation, reducing moisture content by 3%.

Geotourism Potentiality of Fossil Park Using Swot Matrix and Analytical Hierarchy Process (AHP) for Amkhoi Wood Fossil Park, Birbhum District, West Bengal, India

Geoparks are a new tourism form integrating geography and local development, focusing on geological conservation, marketing, and local culture. Geotourism Ecosystem aims to build a stronger network of geoparks. Amkhoi Wood Fossil Park in Birbhum, India, houses 20 million-year-old angiosperm wood fossils. It has been designated a Biodiversity Heritage Site, which aims to protect natural heritage, educate tourists, preserve fossils, and create jobs. Wood fossils from West Bengal, India's, Amkhoi Fossil Park are well known for offering insights into the natural history of the area. The transformation of wood into stone through the process of petrification brings to light natural occurrences such as tree falls and mineral infiltration. The most well-known fossils in the park are from the Glossopteris genus, which represents the Permian period's prehistoric vegetation. Miocene angiosperm wood fossils shed light on the ecological dynamics and evolutionary history of the area. The fossil record of the Anacardiaceae family indicates the warm, humid environment of the area. Using the Saaty scale, the study analyzed the SWOT components and used Eigenvalues to determine each factor's significance. At 54.4%, opportunities have the most weight, followed by vulnerabilities, threats, and strengths. The development of geotourism in the research area is least affected by risk factors. Each SWOT group's high local priority SWOT variables were selected. The greatest potential existed for government officials to give tourism planning more attention. Some of the weaknesses were unusual geological features, insufficient infrastructure, and low awareness. Particularly rare fossils and a geological fossil park are two of the study area's advantages.

Revisiting the Exposed Surface Characteristics on the Stability and Photoelectric Properties of MAPbI3.

CH3NH3PbI3 (MAPbI3), as a promising candidate of photovoltaic materials, has attracted extensive interests due to its excellent photoelectric properties and low preparation cost. However, the relationship between synthesis parameter and performance is still unclear due to the overlook of exposed surface characteristics, limiting the mass-production and commercialization of MAPbI3. Therefore, it is necessary to clarify the stability and photoelectric properties of different exposed surfaces of MAPbI3 under humid environment. In this work, the stability and photoelectric properties of the MAI-terminated and PbI2-terminated of MAPbI3 (001) were thoroughly investigated using density functional theory calculation. To study the stability of exposed surface, adsorption energy of water molecules, ab initio molecular dynamics (AIMD), mean square displacement (MSD) and X-ray diffraction (XRD) were calculated. MSD of PbI2-terminated surface is greater by two orders of magnitude compared to MAI-terminated surface. For the photoelectric properties of MAPbI3, the bandgap, absorption coefficients, joint density of states (JDOS) and dielectric constants were investigated. The inhibitory effect of water on the photoelectric performance for PbI2-terminated surface is more significant than that of MAI-terminated surface. Although the photoelectric properties of water molecules adsorption on MAI-terminated surface is basically unchanged, the diffusion of water molecules reduces the photoelectric properties of MAPbI3. Overall, the stability and photoelectric properties of MAI-terminated surface are superior to PbI2-terminated surface. Therefore, we strongly advocate paying attention to the exposed surface of MAPbI3 during the thin film production process and adjusting synthesis parameters to prepare MAI-terminated surface dominated thin film, which should substantially improve the performance of MAPbI3 in the application.

Enhanced Removal Performance and Economical Efficiency of Volatile Organic Sulfur Compounds by Silver-Modified ZSM-5 Zeolites under a High-Humidity Environment: A Mechanistic Study of the Adsorption-Plasma Catalytic Process.

Dimethyl sulfide (DMS) is a harmful volatile organic sulfur compound (VOSC), which must be effectively controlled. The adsorption-plasma catalytic (APC) process is an efficient and economical route for the elimination of low-concentration VOSCs; however, there are still many challenges in humid environment. In this study, a series of zeolites with different Si/Al ratios and Ag loadings were designed, and were performed for DMS removal by APC process. At 80% relative humidity, the DMS adsorption capacity of Ag5-ZSM25 reached 33.9 mg/g, which was 7.9 times that of ZSM25 and nearly 2 times that of Ag5-ZSM200. Analyses via UV-vis, X-ray photoelectron spectroscopy (XPS), and CO-FTIR confirmed that Ag+ was the predominant species for DMS adsorption and degradation in Ag5-ZSM25. DMS-temperature-programmed desorption (TPD) and density functional theory (DFT) calculations indicated that Ag+ significantly enhanced the binding energy with DMS and weakened the competitive adsorption impact of H2O. In the plasma regeneration stage, Ag5-ZSM25 demonstrated an 89% mineralization, with Ag+ being crucial for DMS mineralization. Based on the in situ plasma DRIFT spectra, a possible degradation pathway for DMS was proposed. The APC process achieved an energy efficiency of 1.66 g/kWh, tripling that of the continuous plasma catalytic process and providing guidance for low-concentration DMS elimination.

Current Advancements in the Behavior Analysis of EPDM Elastomers in Peripheral Applications of the Cathodic Side of PEMFC Systems

This review examines the latest developments in the study of how Ethylene Propylene Diene Monomer (EPDM) elastomers behave in peripheral applications of Proton Exchange Membrane Fuel Cells (PEMFCs), specifically on the cathodic side. The review highlights the crucial role of EPDM in maintaining the integrity and efficiency of PEMFCs in challenging conditions characterized by varying temperatures, humidity, and acidic environments. The study examines the impact of various additives and vulcanization procedures on EPDM's mechanical and chemical properties, demonstrating enhancements in tensile strength, thermal stability, and chemical resistance. The study also investigates the compounding methods and selection of fillers, such as silica and carbon black, to optimize the performance of EPDM. Additionally, the effects of prolonged operational circumstances on EPDM's mechanical integrity and aging resistance in PEMFCs are being examined. This research emphasizes EPDM's suitability for long-term use in fuel cell systems. This review aims to guide the design of more durable and efficient PEMFC systems by optimizing the use of EPDM elastomers.

Effective CO2/N2 adsorptive separation by fluorinated CAG zeolitic imidazolate frameworks in humid environments

Designing and synthesizing stable porous materials for selective carbon dioxide (CO2) capture in humid environments is a paramountly important challenge. In this study, we introduce and present a new hydrophobic fluorinated structure for tetrahedral imidazolate framework-4 (TIF-4) with CAG topology, TIF-4-F. Single-component gas adsorption performance reveals that the CO2 adsorption capacity of TIF-4-F exceeds that of TIF-4 by a dramatic 118.7 % at 298 K and 1 bar. The Langmuir isotherm was utilized to describe the pure CO2 and N2 equivalence, demonstrating that the Ideal adsorbed solution theory (IAST) selectivity for CO2/N2 increased by a remarkable value of 18.9 % that of TIF-4, thereby achieving superior performance among various ZIFs. Grand Canonical Monte Carlo (GCMC) simulations elucidate the adsorption mechanism of CO2 on both materials, with TIF-4-F significantly enhancing its recognition capabilities for CO2. The separation efficacy of two materials was evaluated in a dry CO2/N2 mixture (15/85, v/v), with TIF-4-F showing a significantly prolonged separation time. Furthermore, TIF-4-F maintained its original separation performance over three cycles in a CO2/N2 mixture (15/85, v/v) at 75 % relative humidity (RH). These findings underscore potential applications of TIF-4-F in flue gas and present a viable approach for fluorinated MOFs in CO2/N2 separation.

Investigation of ballistic performance of aramid fabrics modified by polyethylene and graphene in high temperature and humidity environments

Investigation of ballistic performance of aramid fabrics modified by polyethylene and graphene in high temperature and humidity environments

Robust hybrid diffusion control for long-term scalable frost prevention.

Antifrosting surfaces are critical to the efficient and safe operation of infrastructure in cold and humid environments where deposition of frost (porous ice) is thermodynamically inevitable. Such infrastructure can include above-ground power cables and outdoor heat pumps. Here, we introduce a hybrid surface design that passively controls the diffusion of water vapor over a surface to sustain flat frost-free regions for long periods of time. We report more than 150 hours (~1 week) of frost prevention for a single hybrid unit cell, which is three orders of magnitude longer than reported frosting onset for other state-of-the-art techniques. We then demonstrate the potential for large-area frost prevention by scalable tessellation of unit cells and an intrinsic durability to scratches/cracks and physical contamination.

A Multimodal Perception-Enabled Flexible Memristor with Combined Sensing-Storage-Memory Functions for Enhanced Artificial Injury Recognition.

With the continuous advancement of wearable technology and advanced medical monitoring, there is an increasing demand for electronic devices that can adapt to complex environments and have high perceptual sensitivity. Here, a novel artificial injury perception device based on an Ag/HfOx/ITO/PET flexible memristor is designed to address the limitations of current technologies in multimodal perception and environmental adaptability. The memristor exhibits excellent resistive switching (RS) performance and mechanical flexibility under different bending angles (BAs), temperatures, humid environment, and repetitive folding conditions. Further, the device demonstrates the multimodal perception and conversion capabilities toward voltage, mechanical, and thermal stimuli through current response tests under different conditions, enabling not only the simulation of artificial injury perception but also holds promise for monitoring and controlling the movement of robotic arms. Moreover, the logical operation capability of the memristor-based reconfigurable logic (MRL) gates is also demonstrated, proving the device has great potential applications with sensing, storage, and memory functions. Overall, this study not only provides a direction for the development of the next-generation flexible multimodal sensors, but also has significant implications for technological advancements in many fields such as robotic arms, electronic skin (e-skin), and medical monitoring.

Hybrid Thin Film Encapsulation for Improving the Stability of PbS Quantum Dot Solar Cells.

The instability to moisture, heat, and ultraviolet (UV) light is the main problem in the application of quantum dot solar cells (QDSCs). Thin film encapsulation can effectively improve their operational stability. However, it is difficult to achieve multiple barrier effects with single layer of encapsulated film. Here, a hybrid thin-film encapsulation strategy is reported to encapsulate lead sulfide QDSCs, which can isolate moisture and partial thermal, and prevent the penetration of UV light, thus retarding the surface oxidation process of the quantum dots. After 60h, the encapsulated device retains a normalized power conversion efficiency of 83.8% and 80.6% at 85% humidity and 75 °C, respectively, which is three and six times of the value obtained in unencapsulated devices. At continuous UV illumination, encapsulated device exhibits five times higher stability than the reference. This strategy provides the way for the overall improvement of the operating stability of lead sulfide QDSCs in harsh environments of high humidity, high temperature, and UV light.

Copper-Nickel/SiC composites for applications on contact electrodes

Novel copper-nickel matrix composites reinforced with silicon carbide (SiC) micro particles for metal contact applications were manufactured by powder metallurgy technology and were experimentally characterized. Cu and Cu alloys are commonly used as metal contact for either vacuum, oil, or SF6 in low-voltage circuit breaker devices, but their application in environments with the presence of oxygen is limited due to their tendency to form high-resistance copper oxides. Thus, the addition of Ni as an alloying element provides resistance to both humidity and several corrosive environments and increases the composites' hardness, mechanical strength, and wear resistance. Moreover, SiC was chosen due to its contribution to mechanical strength, mouldability, low production cost, and non-reactive nature at ordinary temperatures. Here, three SiC particle size distributions were considered, and it was found that the composites' physical properties are also dependent on the ceramic loading. After evaluating these properties, two specific SiC concentrations were potentially considered for electrode applications: 10 wt% and 20 wt%. The obtained hardness values are in the range of 55 – 65 HR30T which guarantees the necessary strength without detriment of the contact area whereas the welding is minimized. In addition to a homogeneous particle distribution in the solid material, specific wear resistance of ∼10-5 mm3N-1m-1 and electrical conductivities of ∼20 %IACS were obtained. Considering these parameters, Cu-Ni/SiC composites' performance is not compromised compared to commercial Ag/WC materials commonly used in metal contact applications.

Monitoring of insulator pollution discharge in overhead distribution network based on acoustic emission technology

Abstract During the continuous operation of the distribution network, dirt often accumulates on the surface of insulators. Once encountering a humid climate environment, it may cause accidental discharge, leading to the occurrence of flashover pollution accidents. In order to effectively monitor this issue, this study adopted a monitoring method based on acoustic emission technology. This article introduces the discharge process and acoustic emission phenomenon of insulators in overhead distribution networks under pollution conditions. By using emission signal detection devices, acoustic signals generated during insulator discharge are captured. And the wavelet denoising algorithm was used to process its signal, based on which the discharge characteristics of insulator pollution in the overhead distribution network were extracted. The emission amount of insulator pollution in the overhead distribution network was determined according to the set threshold, achieving monitoring of pollution emissions. The results indicate that the proposed method can accurately monitor the discharge of insulators in overhead distribution networks, provide scientific basis for timely maintenance measures, and improve the operational safety and reliability of distribution networks.

Inorganic-Derived 0D Perovskite Induced Surface Lattice Arrangement for Efficient and Stable All-Inorganic Perovskite Solar Cells.

The inverted inorganic CsPbI3 perovskite solar cells (PSCs) are prospective candidates for next-generation photovoltaics owing to inherent robust thermal/photo-stability and compatibility for tandems. However, the performance and stability of the inverted CsPbI3 PSCs fall behind the n-i-p counterparts due to poor energetic alignment and abundant interfacial defect states. Here, an inorganic 0D Cs4PbBr6 with a good lattice strain arrangement is implemented as the surface anchoring capping layer on CsPbI3. The Cs4PbBr6 perovskite induces enhanced electron-selective junction and thus facilitates efficient charge extraction and effectively inhibits non-radiative recombination. Consequently, the CsPbI3 PSCs with Cs4PbBr6 demonstrate the highest power conversion efficiency (PCE) of CsPbI3-based inverted PSCs, reaching 21.03% PCE from a unit cell and 17.39% PCE from a module with a 64 cm2 aperture area. Furthermore, the resulting devices retain 92.48% after 1000h under simultaneous 1-sun and damp heat (85°C / 85% relative humidity) environment.

Design and performance analysis of a low-cost monitoring system for advanced building envelopes

The objective of this study is to design a low-cost system for long-term monitoring of advanced building envelope and evaluates its performance in comparison to conventional lab-grade sensors. Leveraging the potentials of a single-board computer and several low-cost digital sensors, the system measured thermo-physical and environmental parameters, including temperature, humidity, CO2 levels, airflow rate, lighting, and heat flux. The system's architecture allowed for easy integration and flexible connectivity, providing comprehensive monitoring capabilities at a fraction of the cost of lab-grade systems. A basic prototype is available in a GitHub repository. The systematic evaluation of the proposed concept involved three key experiments using a double-skin façade mockup installed in a full-scale climate simulator. Sensor accuracy over 24 hours was assessed through time-series comparison, showing high accuracy in recording air temperature, humidity, and surface temperature without on-site calibration, though calibration was essential for precise CO2 and lighting measurements. Key performance indicators of the thermophysical behavior of envelope systems, such as U-value and g-value, were derived for both the low-cost and lab-grade setups. Discrepancies of up to 7% in U-value and 13% in g-value were observed, confirming the system's reliability for building energy assessments. Additionally, the low-cost system effectively represented dependencies between independent and dependent variables, as shown by analysis of variance, closely aligning with the picture obtained from lab-grade sensors’ data. These findings validate the low-cost monitoring system as a viable, cost-effective alternative for advanced building envelope performance studies and indoor environmental quality assessments, highlighting the need for calibration of certain sensors.

Neutron tomography and image registration methods to study local physical deformations and attenuation variations in treated archaeological iron nail samples

This study presents a preliminary examination of the effects of environment changes post-excavation on heavily corroded archaeological Roman iron nails using neutron tomography and image registration techniques. Roman nails were exposed to either a high relative humidity environment, or fast thermal drying as primary experiments to show the power of this imaging technique to monitor and quantify the structural changes of corroded metal artifacts. This research employed a series of pre- and post-treatment tomography acquisitions (time-series) complemented by advanced image registration methods. Based on mutual information (MI) metrics, we performed rigid body and affine image registrations to meticulously account for sample repositioning challenges and variations in imaging parameters. Using non-affine local registration results, in a second step, we detected localized expansion and shrinkage in the samples attributable to imposed environmental changes. Specifically, we observed local shrinkage on the nail that was dried, mostly in their Transformed Medium (TM), the outer layer where corrosion products are cementing soil and sand particles. Conversely, the sample subjected to high relative humidity environment exhibited localized expansion, with varying degrees of change across different regions. This work highlights the efficacy of our registration techniques in accommodating manual removal or loss of extraneous material (loosely adhering soil and TM layers around the nails) post-initial tomography, successfully capturing local structural changes with high precision. Using differential analysis on the accurately registered samples we could also detect and volumetrically quantify the variation in moisture and detect changes in active corrosion sites (ACS) in the sample. These preliminary experiments allowed us to advance and optimize the application of a neutron tomography and image registration workflow for future, more advanced experiments such as humidity fluctuations, corrosion removal through micro-blasting, dechlorination and other stabilization treatments.

High Humidity Alters Myeloid-Derived Suppressor Cells in Spleen Tissue: Insights into Rheumatoid Arthritis Progression.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and bone destruction, leading to severe complications. Previous research has suggested that high humidity conditions may exacerbate RA, however, the underlying mechanisms remain unclear. Furthermore, there is a lack of evidence linking humidity to the worsening of RA symptoms in animal models. The Collagen-induced arthritis (CIA) mouse model was established using C57BL/6 mice. The arthritis status of the mice was evaluated under two distinct humidity conditions (50% and 80%). The aim of the present study was to investigate the impact of elevated humidity levels on the types of splenic cells present using mass spectrometry flow. Additionally, the study utilized MDSCs, which are significantly upregulated by high humidity, to assess the levels of oxidative stress and conducted mRNA sequencing of sorted MDSCs to investigate their impact on arthritis in CIA mice. Compared to normal humidity, high humidity exacerbated arthritis incidence in mice, resulting in increased arthritis scores, swelling, serum autoantibodies (anti-COII and anti-CCP), and upregulation of pro-inflammatory cytokines. Significant variations were observed in the spleen index under high humidity condition, accompanied by noticeable inflammatory alterations. Moreover, elevated humidity levels induced a substantial modulation in MDSCs population in the spleen of CIA mice, along with alterations in oxidative stress markers such as heightened serum ROS levels, and increased expression of COX, SOD, and Nrf2 mRNA. Following successful sorting of MDSCs, mRNA sequencing revealed a decrease in the expression of Rap1 signaling pathway under high humidity environment, which may contribute to the increase of MDSCs cells and aggravate the progression of RA disease. A comprehensive analysis of the available data reveals a detrimental impact of high humidity on MDSCs numbers within spleen tissue, with potential implications for the development of RA.

Fabrication and adsorption properties of hierarchical NaY zeolite with mesopores in the range of 2–5 nm

Adsorption is one of the most effective methods for controlling the concentration of VOCs pollution. In this work, the hierarchical NaY zeolites with size-controlled mesopores in the range of 2–5 nm are obtained via NH4HF2-etching and surfactant-templating process. By using the different cationic surfactant (CnTAB), we fabricate the surfactant-templated zeolite with controllable mesopores, and improve its adsorption capacity for toluene. In addition, the modified zeolite’s hydrophobicity is enhanced, and it maintains a high adsorption capacity in a complex humid environment.