Sea Salt Research Articles

Associations of exposure to PM2.5 and its compounds with carotid intima-media thickness among middle-aged adults

BackgroundExposure to fine particulate matter (PM2.5) has been linked to an increased risk of atherosclerosis. However, it remains unclear whether specific compounds within PM2.5, rather than the overall mass, serve as a better indicator of adverse cardiovascular health outcomes associated with air pollution. MethodsIn this cross-sectional study, we included 3257 participants (aged 37–51 years) from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Exposure to PM2.5 and its constituent compounds, black carbon (BC), ammonium, nitrate, organic matter, sulfate, mineral dust, and sea salt were included in the analyses. Carotid intima media thickness (cIMT; the average of common, bulb, and internal carotid) was measured by carotid ultrasonography. We assessed the cross-sectional associations of one-year exposure to PM2.5 and its compounds with mean cIMT using linear regression models adjusting for participants' demographics, individual- and neighborhood-level socioeconomic status, behavioral components, and health conditions. We also adopted Bayesian kernel machine regression (BKMR) models to investigate the association between the PM2.5 compound mixture and cIMT as well as the contribution of each compound to the association. ResultsGreater exposure to BC was associated with higher cIMT (mm) (β =0.034, 95 % CI = 0.019–0.049, per IQR increase [0.56 μg/m3] of BC) among participants with a mean age of 45.0, consisting of 45.9 % Black and 54.1 % White males and females. The association was generally consistent across participants' demographic characteristics. In our BKMR analysis, BC exhibited a dose-response association with cIMT with a high contribution to the association of cIMT with PM2.5 compound as a mixture (posterior inclusion probability [PIP]: 1.00). ConclusionsOur findings suggest that certain compounds of PM2.5, such as BC, may offer more reliable indications of the impact of air pollution on cardiovascular health.

Root-Driven Soil Reduction in Wadden Sea Salt Marshes

The soil redox potential in wetlands such as peatlands or salt marshes exerts a strong control over microbial decomposition processes and consequently soil carbon cycling. Wetland plants can influence redox by supplying both terminal electron acceptors (i.e. oxygen) and electron donors (i.e. organic matter) to the soil system. However, quantitative insight into the importance of plant effects on wetland soil redox and associated plant traits are scarce. In a combined mesocosm and field study we investigated the impact of plants on soil reduction using IRIS (Indicator of Reduction in Soils) sticks. Vegetated plots were compared to non-vegetated plots along an elevational gradient in a salt marsh of the Wadden Sea and along an artificially created gradient in a tidal tank mesocosm experiment. Our findings from the mesocosm experiment demonstrated that vegetation both enhanced and suppressed soil reduction relative to non-vegetated control pots. The direction of the plant effect (i.e., net oxidizing or net reducing) was inversely correlated with background redox conditions. Insights from high-resolution oxygen profiling via planar optode imaging corroborated these findings. In the field study, vegetation consistently reduced the comparatively well-aerated Wadden Sea salt marsh soil. Reduction correlated positively with soil organic matter content and belowground biomass, indicating that greater availability of plant-derived electron donors, in the form of organic matter, increased soil reduction. Challenging the dominant paradigm that wetland plants primarily act as soil oxidizers, our study reveals their potential to exert a net reducing effect. The documented impact of these plant-induced changes in soil redox conditions suggests a previously overlooked role in shaping the stability of soil organic carbon stocks in wetland ecosystems with variable water tables.

Combined Impacts of Temperature, Sea Ice Coverage, and Mixing Ratios of Sea Spray and Dust on Cloud Phase Over the Arctic and Southern Oceans

AbstractWe analyze the importance of cloud top temperature, dust aerosol, sea salt aerosol, and sea ice cover for the thermodynamic phase of low‐level, mid‐level, and mid to low‐level clouds observed by CloudSat/CALIPSO over the Arctic and the Southern Ocean using an explainable machine learning technique. As expected, the cloud top temperature is found to be the most important parameter for determining cloud phase. The results show also a predictive power of sea salt and sea ice on the phase of low‐level clouds, while in mid‐level clouds dust shows predictive power. Over the Southern Ocean, strong zonal winds coincide with the aerosol distribution. While they can produce high mixing ratios of sea spray at lower levels, the strong zonal winds may prevent the pole‐ward transport of dust. Sea ice may prevent the release of sea salt aerosols and marine organic aerosols leading to higher liquid fractions in clouds over sea ice.

Comparison of Conventional and Microwave Heating

Carnot batteries (or Power-to-Heat-to-Power systems) are capable of increasing the use of electricity from photovoltaic or wind power plants to achieve decarbonisation of the electricity sector. To decouple electricity production from demand, these renewable power plants can be connected to the thermal energy storage system of a concentrated solar thermal power plant via electric heaters. As an alternative to electric heaters, microwaves are studied as a volumetric and selective heating method, avoiding the limitations of the Joule effect conventional heating when having solar salt (non-eutectic mixture of 60 wt % NaNO3 and 40 wt % KNO3), which is a storage medium with low thermal conductivity, working at a temperature very close to its affordable maximum temperature without degradation. In this work, the two heating methods are compared both experimentally and numerically. At experimental level, a microwave oven and a muffle furnace are used to record energy consumption and time for a common objective. Additionally, different crucible materials were used to test their suitability with microwaves. Only quartz glass was validated for microwave heating, while the porcelain and alumina based materials (Corundum and Alsint 99.7) failed while exposed to microwaves. Compared to conventional heating, heating solar salt with microwaves saved fifty minutes of time and ninety percent of consumption. These experiments were validated by numerical simulations, showing a different distribution in each experiment.

Thermal energy storage behaviour of 3D ceramic/molten salt structures under real concentrated solar radiation

Molten salts, phase change materials commonly employed in thermal energy storage (TES) systems, are widely known to enhance the efficient use and storage of solar energy in concentrated solar power (CSP) plants. Here, three-dimensional TES (3DTES) have been manufactured from highly porous (up to ∼90 %) 3D printed patterned vermiculite (V) and alumina (Al2O3) supports, which have been infiltrated with molten sodium nitrate salt (nn) and solar salt (ss). These 3DTES have been validated under real concentrated solar radiation in a parabolic solar furnace. Among the different 3DTES, those based on V-nn exhibits the best efficiency for the conversion of the incident solar radiation into heat; whereas Al2O3-nn transfers the heat more efficiently and allows a faster charging-discharging cyclability due to its higher thermal conductivity. This study confirms the benefits of additive manufacturing to develop a new class of innovative TES for CSP applications.

Computational Study of the Formation of Atmospheric Aerosol Precursors Under Ambient Conditions: A Case Study of the Interaction Between Sea Salt, Water, and Sulfuric Acid Molecules

ABSTRACTCluster formation has significant implications in atmospheric science and environmental chemistry. These clusters are characterized by complex interactions between their constituents, which influence their structure, stability, and growth. Experimental investigations are difficult for the initial stages of prenucleation cluster formation, which leads to larger aerosols. To understand the formation of clusters, the interactions between sea salts (NaCl, KCl, and MgCl2), water, and sulfuric acid molecules have been investigated. Each step has been comprehensively examined and thermodynamic parameters have been computed using DLPNO‐CCSD(T)/CBS//M06‐2X/6‐311++G(3df,3pd) to find the stabilities of the molecular complexes. Among all complexes, the binding energies of cluster (SS)1(W)1(SA)3 are found to be the lowest due to the formation of HCl, hydrogen bonding, and weak van der Waal forces. Sea salts have shown a more favorable interaction with H2SO4 compared to H2O molecules. The addition of H2SO4 increases the reactivity of the cluster (SS)1(W)n, while the addition of H2O molecules reduces the reactivity of the cluster (SS)1(SA)n. However, further addition of H2SO4 or H2O to the existing cluster (SS)1(W)n(SA)n increases the free energy of formation. Furthermore, the influence of temperature was also investigated, suggesting that complex formation is slightly more favorable at lower temperatures than at higher temperatures. The negative values of thermodynamic parameters indicate, that these complexes are spontaneous and exothermic over the colder regions.

Evaluation of three inert materials in controlling Cowpea weevil (<em>Callasobruchus maculatus</em> F.) on stored cowpea (<em>Vigna unguiculate</em> L.)

Eco-friendly inert materials can be achieved minimizing insect damages, this study was conducted to explore the efficacy of the three inert materials at 20% (w/w) paddy husk ash (PHA), fine dry sea salt and tiny bricks against the cowpea weevil C. maculatus on stored cowpea (V. unguiculata) on the basis of adulticidal effects and asses the influence against germination losses of the seeds. The result exhibited a significant difference (p≤ 0.0001) in their level of weevil attack during the storage. Maximum 100% adult mortality was recorded in the cowpea seeds incorporated with PHA after 96 hours of the treatment followed by dry salt it was observed 94% at the 5th day whereas, tiny bricks killed only 20% weevils as untreated control until 5th day after the treatment. Further, PHA treated seeds much reduced the capable of the egg laying capacity of weevil (9.8± 0.58eggs/ female) as well as minimized the production of new progenies (13.6 ± 0.37) and also there were recorded 0.03% weight loss and zero percent germination losses proving it to be best protectant on stored cowpea. However, significantly (p≤ 0.0001) any adverse effects that, egg laying capacity and new progeny production did not visible in dry salt up to 90 days after the treatments except minimize the germination loss. Among the inert materials used, tiny bricks were found ineffective to cause adult mortality, fecundity and adult emergency in F1 generation (119.8± 1.78), it was further increased production of new weevils obtained following the next F2 generation (1301 ± 0.65) and play down the losses of weight and germination of the seeds. Considering it was noticed tiny bricks treated seeds significantly equivalence with the level of damage by the weevil C. maculatus in untreated control on stored cowpea.

Contract Farming & Cost of Funding: Evidence from Madurase Solar Salt Small Businesses

This study aimed to estimate the indirect expenses borne by tenant farmers due to credits they receive in community salt farming operations managed through contract farming systems in Pamekasan Regency. Credits constitute a crucial aspect of tenant farmers’ rights within the community salt farming contract farming framework. This study employed a comparative analysis of the cost of funds based on the adopted contract farming models, specifically the two-way and three-way contract farming structures. Moreover, it investigated the correlation between the cultivated salt field’s size and the magnitude of the cost of funds endured by tenant farmers. The results of the analysis reveal that the average costs of funds borne by tenant farmers are notably high, ranging from 5.24% to 6.71% per month. Surprisingly, these figures exceed the loan interest rates offered by two formal financial institutions: BRI and Bank JATIM. Another significant finding is the positive correlation between the size of cultivated salt fields and the magnitude of the cost of funds borne by tenant farmers. Lastly, there is a clear positive relationship between the credit amount received and the corresponding cost of funds endured by tenant farmers. The substantial costs of funds shouldered by tenant farmers involved in the community salt farming, operated through contract farming systems in Pamekasan Regency, signify inefficiencies within the contract farming structure. It is expected that the government can aid these tenant farmers by disbursing subsidized credits through collaborations with relevant ministries and local formal financial institutions.

Anticancer effects of washed-dehydrated solar salt doenjang and its metabolites

AbstractIn this study, the anticancer effect of doenjang according to the type of salt was investigated. Three samples were prepared: doenjang made with purified salt, doenjang made with generally manufactured solar salt, and doenjang made with washed and dehydrated solar salt (WDSD). In mice in which colon cancer was induced with azoxymethane/dextran sodium sulfate, doenjang made with solar salt, especially doenjang made with washed and dehydrated solar salt, was found to have a much higher colon cancer inhibition effect. WDSD significantly promoted the mRNA expression of apoptosis-related factors such as Bcl-2–associated X protein (Bax) and caspase 9 and the cell cycle arrest-related factors p53 and p21, and conversely significantly reduced the mRNA expression of apoptosis inhibitors such as B-cell lymphoma-2 (Bcl-2) (p < 0.05). Additionally, metabolites were investigated to determine which substances in WDSD exhibit this anticancer effect. As a result, the contents of isoflavone and soyasaponin B in the form of aglycons such as genistein, daidzein, and glycitein, which are known to have anticancer and anti-inflammatory properties, were found to be significantly high. Therefore, the results confirmed that doenjang prepared with washed and dehydrated solar salt has superior anticancer potential against colon cancer, and that various active ingredients contribute to the improvement of this functionality.

Carbon dioxide sequestration through mineralization from seawater: The interplay of alkalinity, pH, and dissolved inorganic carbon

Marine carbon dioxide removal technologies rely on the equilibration of the seawater with atmospheric CO2, where a pH increase can facilitate carbon dioxide removal either through increased absorption capacity of CO2, or precipitation of minerals. Here, we focus on explicitly defining the governing factors that influence seawater alkalinity with respect to CaCO3 mineralization and atmospheric CO2 uptake. We utilize an electrochemical setup and different water types, from near-shore Mediterranean seawater as well as Red Sea Salt water. The setup allows us to separate mineralization from alkalinity enhancement via an electrochemical membrane cell, and a second compartment with controlled environment, where the interplay of ion concentration, precipitation, pH, DIC concentration, and total alkalinity are evaluated. The effect of sparging additional carbon dioxide before, and after the precipitation of CaCO3 was evaluated while utilizing both a mild pH swing (from, ∼8.3 to ∼9.5), and a larger pH swing (from, ∼8.3 to ∼10.2). A thermodynamic model is presented defining the energy consumption to increase the pH, and the influence of Mg thereon is explicated. Furthermore, we detail theoretical aquatic chemistry simulations via PHREEQC to rationalize the observed intricate dynamics of the carbonate system in seawater. We end with a discussion of the implications of total alkalinity, pH, salt complexation, and carbon uptake capacity relevant to of all ocean alkalinity enhancement and marine based carbon dioxide removal systems, concluding that the carbon uptake capacity of water returned to the ocean must be verified in such technologies

Size-segregated particulate matter oxidative potential near a ferromanganese plant: Associations with soluble and insoluble elements and their sources

The oxidative potential (OP) of particulate matter (PM) is considered a better health metric of PM exposure than mass concentration since its value is highly dependent on PM composition. OP assays have shown different sensitivities to PM components and particle sizes. In this work, an urban-industrial mixed site with high levels of airborne Mn and Fe, due to the proximity of a ferromanganese alloy plant, was chosen to study the association between PM elements and three OP assays (ascorbic acid (AA), dithiothreitol (DTT), and 2,7-dichlorofluorescein (DCFH)) in size segregated PM samples (PM10-2.5 and PM2.5). Urban samples from a nearby area were also collected. The concentration of 39 elements in both the soluble (in a phosphate buffer aqueous solution) and insoluble fractions of PM10-2.5 and PM2.5 was determined by ICP-MS. Soluble elements were then associated with OP and local sources using Principal Component Analysis (PCA). Four sources of soluble elements have been identified in the urban-industrial site. The main factor was attributed to road traffic; although Cu and Fe, two active transition metals in OP assays, were associated to this factor, their low solubility, mainly in the coarse fraction, has led to low factor loadings of OP; the second factor was attributed to a ferromanganese plant, since it presented the highest factor loadings for soluble Mn in both PM10-2.5 and PM2.5; it was the main factor associated with OP-DTT and OP-DCFH values, mainly in the coarse fraction. Crustal material and sea salt aerosol were also identified as sources.

Effects of Sodium Chloride on PEMFC Durability at a Concentration Close to that of a Marine Environment

The marine application of proton exchange membrane fuel cells (PEMFCs) requires special attention due to sea salt aerosols and atmospheric pollutants, susceptible to degrade these systems and induce performance losses. To the best of our knowledge, this study is the first to identify the performance losses of PEMFCs due to sodium chloride (NaCl) pollution similar to that of the marine environment. A 641 h ageing test with a NaCl concentration in air of 120 μg.m‒3 was carried out on a five cells stack of 220 cm2. The results reveal a key mechanism for reversible performance loss, namely the deposition of salt particles in the channels and on the surface of the cathode gas diffusion layer (GDL). This can lead to the complete shutdown of a cell. Nonetheless, this contamination did not induce significant irreversible performance losses as the restarts of the stack cause the salt particles to dissolve. An overall degradation rate of 8 μV·h‒1, similar to that of the baseline without NaCl contamination, is observed.

Evaluation of Biosurfactants to Preflush for Offshore Wells.

With the improvement of environmental protection requirements in offshore oil and gas exploration, there is a great demand to find environmentally friendly surfactants for cementing preflush fluids. In the present paper, the application potential of three biosurfactants of rhamnolipid, lipopeptide, and sophorolipid in the preflush fluid was evaluated through a series of experiments. The experiments studied the interfacial tension (IFT) of the biosurfactants, resistance to temperature, salt resistance (sodium chloride and sea salt), and the influences of the studied biosurfactants on the rheological compatibility and capabilities to convert the wettability of the formation from oil-wet to water-wet, mud cake removal efficiency, and to improve the interfacial bonding properties of the preflush fluid. The results showed that rhamnolipid, lipopeptide, and sophorolipid exhibited excellent surface activities in high-temperature and sodium chloride (NaCl) environments. When exposed to sea salt, lipopeptides lost their function due to agglomeration, while rhamnolipids and sophorolipids maintained structural stabilities and high surface activities. When rhamnolipid was mixed with sophorolipid in a ratio of 2:1 at the same concentration, the combined biosurfactant had the best surface activity among the studied surfactants. The combined biosurfactant not only had good rheological compatibility with the drilling fluid and cement slurry but also showed excellent properties in the removal of mud cake. In addition, the effect of the removal of the mud cake was verified by the gas channeling experiment. The experimental results show that the presence of mud cake can reduce the bonding strength. When rhamnolipid was mixed with sophorolipid in a ratio of 2:1 at the same concentration, the removal efficiency of mud cake was the highest, and the interfacial bonding property of the cement sheath can be improved.

Controls on the stable Mo isotopic composition of inner-continental precipitation

The molybdenum (Mo) isotope budget of the surface environment has been well characterized in recent decades, facilitating accurate mass balance modeling of the ancient redox-driven Mo cycle. One yet unresolved component is the range of possible processes and sources that result in isotopically heavy river waters relative to continental sources. Following a recent hypothesis that isotopically heavy δ98Mo of precipitation may control the final δ98Mo of river water relative to its continental source bedrock, we investigated the δ98Mo composition of 19 snow samples from three locations in Central Europe: the Swiss Alps (“Alpine” samples) from the Hochalpine Forschungsstation Jungfraujoch (HFSJ) in both summer and winter, the Swiss Jura Mountains in winter and the French Vosges Mountains in winter. Stream waters from two snowmelt-fed streams were additionally collected from the Alpine site. Snow sample δ98Mo compositions were highly variable, ranging from −0.03 to +1.93 ‰, with no clear mixing trends indicating complex sources, source pathways, or post-depositional processing. Only the winter snow samples from the high-altitude HFSJ site had δ98Mo values consistently heavier than typical continental crust. The δ98Mo results were coupled with radiogenic Sr isotopic, major ion, and trace element compositions as tracers for three major sources of airborne ion inputs: sea salt, mineral dust, and anthropogenic aerosols. We found that the most likely source of Mo to precipitation in the lower elevation Vosges and Jura Mountains samples was isotopically light soil mineral dust, which reflected the underlying bedrock sources, with a likely additional anthropogenic component. The isotopically heavy winter snow samples at the elevated HFSJ site were attributed to a higher input of carbonate mineral dust from long-distance transport of carbonate-rich Saharan dust, which was overwritten in the summer by an influx of low elevation sources transported upwards during higher vertical thermal mixing. Finally, we concluded that precipitation has a negligible direct effect on the overall Mo content and isotopic composition of inner continental European streams and rivers relative to other sources, such as bedrock weathering. Future time-series studies may augment these conclusions to show possible heterogeneity of precipitation as well as the addition of sample sites closer to marine sources, where a larger flux of isotopically heavy marine aerosols to streams might be expected.

Li/Na/K carbonate solar salts for enhanced and integrated carbon capture and utilization via reverse water gas shift (ICCU-RWGS)

This study introduces a novel ICCU-RWGS process using Li, Na, and K carbonates mixed with boric acid as dual functional materials, enhancing CO2 capture and conversion without traditional CaO adsorbents. These molten salts, compatible with solar energy systems, enable efficient integration with CSP, storing heat from CO2 capture for utilization. The addition of boric acid significantly boosts CO2 uptake and conversion, achieving 2.0 mmol, 1.1 mmol, and 1.3 mmol CO2 uptake with conversion of 51.1 %, 58.3 %, and 57.6 % over three cycles, respectively. A 10-cycle test confirmed stable performance, with conversion rates between 53.0 % and 58.7 %. Characterization techniques (XRD, SEM, TEM, XPS, in-situ DRIFTS) revealed new borate phases after CO2 capture. TG-DSC analysis showed exothermic peaks during CO2 capture and RWGS stages, indicating that molten salt has the potential to generate heat for CSP systems, thus offering efficient CO2 conversion and sustainable energy recovery.

Exogenous Application of Selenium Nanoparticles (Se-NPs) to Mitigate Salt Stress in Soybean-Evaluation of Physiological, Molecular and Biochemical Processes

AbstractSalt stress is identified as a significant abiotic stress that hampers agricultural sustainability globally. The study was carried out to investigate the potential mitigating effects of selenium nanoparticles (Se-NPs) on salt stress in soybean. Two weeks old grown soybean seedlings were subjected to salt stress conditions (4000 mg L− 1 of sea salts). The plants were foliar sprayed with Se-NPs at concentrations of 0.0, 0.5, 1.0 and 1.5 mg L− 1 twice. The first application was applied at four weeks from sowing and the second application was added after two weeks from the first application. Compared to control, Se-NPs application mitigates the negative effect of salinity on plant growth to a variable extent. This improvement may be attributed to several factors such as increased the concentrations of photosynthetic pigments, total soluble sugars and total protein. In addition, Se-NPs alleviated the adversely effect of oxidative stress by increasing the antioxidant activities and potassium contents without markedly increase in the sodium content of the soybean leaf tissues. Also, Se-NPs enhanced the biosynthesis of secondary metabolites such as total phenolic content under salinity. Moreover, Se-NPs spray significantly reinforced the development of conducting secondary tissues in the leaves and roots of the treated plants. GmHKT1 gene transcription was markedly up-regulated in salinized soybean and foliar sprayed with Se-NPs as a molecular strategy to cope with the salinity. Based on the obtained results, among the different doses of Se-NPs, soybean plants sprayed with 1.0 mg L− 1 Se-NPs showed better salt tolerance. The foliar spray of Se-NPs may be considered as a promising approach to enhance salt tolerance in soybean plants, which could have significant implications for improving agricultural sustainability in salt-affected regions.

Novel and stable carbon black/polyvinyl acetal aerogels efficiently harvesting solar energy for seawater desalination

A novel interfacial solar steam generators (ISSG) was prepared by a porous carbon black/polyvinyl acetal aerogel (CPA) with high light-absorbing hydrophilic properties, to achieve efficient solar-driven water evaporation and seawater desalination. The polyvinyl acetal was produced by the aldol condensation reaction of polyvinyl alcohol(PVA) and glutaraldehyde(GA). It was freeze-dried to create a hydrophilic porous structure that constructs an efficient hydrophilic channel. Carbon black (CB) exhibits high light absorption capabilities. Incident light undergoes multiple scattering within its porous network structure, effectively reducing reflected light energy loss and enabling efficient thermal conversion of sunlight. Benefited from its highly light-absorbing porous hydrophilic structure, CPA-40-3 evaporation rate achieves an impressive 3.23 kg·m−2·h−1 and an evaporation efficiency of 94 % under 1 sun irradiation, without obvious decay even during long-term use. Furthermore, CPA-40-3 demonstrates remarkable salt tolerance, the evaporation rate remains at 2.55 kg·m−2·h−1 although in simulated Dead Sea salt water under 1 sun irradiation. Compared to traditional ISSG, the CPA has advantages such as superior mechanical properties, prevention of surface salt precipitation, faster water supply, and a larger light absorption area. This design had tremendous promise for efficient solar desalination due to its extraordinarily high evaporation performance in high-salinity brine.

Thermodynamic analysis of an advanced adiabatic compressed air energy storage system integrated with a high-temperature thermal energy storage and an Organic Rankine Cycle

Advanced adiabatic compressed air energy storage (AA-CAES) system has drawn great attention owing to its large-scale energy storage capacity, long lifespan, and environmental friendliness. However, the performance of the air turbine during the discharging process is limited by the low temperature of the compression heat. Thus, this study proposes an integrated AA-CAES system incorporating high-temperature thermal energy storage and an Organic Rankine Cycle (ORC). The high-temperature thermal energy storage is introduced to heat the discharging compressed air to enhance the air turbine performance, and the Organic Rankine Cycle is integrated to utilize the waste heat. Notably, two preheaters are deployed in a special tandem to recover the heat from the air exiting the turbine and the water exiting the hot water tank, respectively. This paper develops a thermodynamic model to simulate the proposed system, assessing the effects of heat storage temperature, ambient temperature, and inlet conditions of the air turbine on performance metrics, including exergy efficiency and exergy destruction. The simulation results indicate that, compared to thermal oil and Hitec salt, employing solar salt as the heat storage medium for the solar thermal collection and storage unit yields the best performance. The energy storage efficiency, roundtrip efficiency, exergy efficiency, exergy conversion coefficient, and energy storage density of this system are 115.6 %, 65.7 %, 78 %, 79.4 %, and 5.51 kWh/m3, respectively. Exergy analysis reveals that the exergy efficiency of interheaters (IH) is the lowest at 76.7 %, while air turbines (ATBs) exhibit the highest exergy efficiency at 91.2 %. Moreover, due to the irreversible processes of compression, expansion, and throttling, ATBS, compressors, and throttle valves collectively contribute to an exergy destruction rate as high as 79.2 %. The parameter analysis demonstrates that low ambient temperature, high inlet temperature, and high inlet pressure of the air turbine enhance energy storage performance.

A Molecular Dynamics Study of the Influence of Low-Dosage Methanol on Hydrate Formation in Seawater and Pure Water Metastable Solutions of Methane

The behavior of low concentrations of methanol (0.5 and 1.0 wt% of water) as a promoter for hydrate formation in seawater or pure water metastable solutions of methane was investigated using the classical molecular dynamics method at moderate temperature and pressure. The influence of methanol on the dynamics of the re-arrangement of the hydrogen bond network in seawater and pure water solutions of methane was studied by calculating order parameters of the tetrahedral environment and intermolecular torsion angles for water molecules, as well as by calculating the number of hydrogen bonds, hydrate, and hydrate-like cavities. It was found that hydrate nucleation can be considered a collective process in which the rate of hydrate growth is faster in systems with low concentrations of methanol, and confident hydrate growth begins earlier in a metastable solution without sea salt with a small amount of methanol than in systems without methanol.

The Affordable Virtual Learning Technology of Sea Salt Farming across Multigenerational Users through Improving Fitts’ Law

Sea salt farms are the source of salt, an indispensable essential ingredient in various foods and products. Further, they act as frontlines to protect marine disasters from entering domestic residential areas. However, sea salt farming has decreased in popularity among recent-generation farmers in Samut Songkhram Province, Thailand. This paper presents the development of an affordable virtual learning (AVL) application for Thailand’s sea salt farming. Fitts’ law was applied to optimize user-interactive objects’ size and placement to reduce selection time. The sample consisted of 127 multigenerational users, namely those in Generation X, Generation Y, and Generation Z. This study found that the developed AVL applied Fitts’ law to be used harmoniously with VR economical equipment. A total of 90.55% of multigenerational users were satisfied with the developed AVL. The “Looking” and “Executing by eye focus” activities were enjoyed by 100% of participants. The following activities were “Walking” and “Listening”, with 82.68% and 77.95% enjoying them, respectively. Generation Z users responded more to the “Walking” activity than Generation X and Y users. In addition, the hypothesis testing result of learning outcomes through AVL was consistent among multigenerational users. Therefore, the developed AVL should be used as a medium to conserve sea salt farming in Thailand.