Salt Content Research Articles

Pemetaan Sebaran Salinitas di Desa Tanjung Pakis Kabupaten Karawang Menggunakan QGIS

The coastal area has a high likelihood of seawater intrusion, leading to the formation of brackish water. Brackish water is unsafe for consumption due to its high salt content, which exceeds 0.5 ppt. The purpose of this study is to identify the distribution of salinity by testing the well water of the residents in Tanjung Pakis Village, Karawang Regency. The sample determination method used is Systematic Grid Sampling. The grid used measures 1,000 x 250 m. In this study, 3 grids were used, each at different distances from the nearest coastline. Three samples were taken from each grid, resulting in a total of 9 samples. The parameter tested is salinity, which represents the salt content in the water. The method used to measure the salinity parameter is direct reading using a refractometer. The results of the study show that the highest salinity parameter value reached 120 ppt in Grid I, while the lowest salinity parameter value was 30 ppt in Grid II. The mapping results indicate high salinity values in Grid I, represented by a darker color. In Grid II, the salinity value decreases, indicated by a lighter color. An increase in salinity occurs in Grid III, shown by a darker color compared to Grid II.

Effect of Iron and Zinc Fertilization on Growth and Yield of Mustard (Brassica juncea L.) in Loamy Sand

A field experiment was conducted during rabi 2022-23 at Agronomy Instructional Farm, Chimanbhai Patel College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar. The soil of the experimental field was loamy sand in texture, neutral to alkaline in reaction, normal with respect to salt content, low in available nitrogen and sulphur, medium in available phosphorus, potash, zinc and iron and high in manganese and copper. Nine treatment combinations comprising three levels of iron 0.0 kg Fe ha-1 (Fe0), Soil application of 20.0 kg FeSO4. 7H2O ha-1 (Fe1) and 0.5 % FeSO4. 7H2O foliar spray at 30 and 45 DAS (Days after sowing) (Fe2) and three levels of zinc 0.0 kg Zn ha-1 (Zn0), Soil application of 10.0 kg ZnSO4. 7H2O ha-1 (Zn1) and 0.5 % ZnSO4. 7H2O foliar spray at 30 and 45 DAS (Zn2) were evaluated in randomized block design with factorial concept with four replication. Mustard variety GDM 4 was used as a test crop. Significantly higher number of secondary branches plant-1 (16.59), number of siliquae plant-1 (341.4), test weight (5.18 g), seed yield (2061 kg ha-1) and stover yield (4976 kg ha-1) were recorded with soil application of 20.0 kg FeSO4. 7H2O ha-1 (Fe1) but it was at par with 0.5 % FeSO4. 7H2O foliar spray at 30 and 45 DAS. Stover yield of mustard remained at par with 0.5 % FeSO4. 7H2O foliar spray at 30 and 45 DAS. Significantly higher number of secondary branches plant-1 (16.37), number of siliquae plant-1 (340.1), seed (2001 kg ha-1) and stover yield (4961 kg ha-1) were recorded with soil application of 10.0 kg ZnSO4. 7H2O ha-1 (Zn1) but it was at par with foliar spray of 0.5 % ZnSO4. 7H2O at 30 and 45 DAS except seed yield of mustard.

Halophilic Pectinase-Producing Bacteria from Arthrocnemum macrostachyum Rhizosphere: Potential for Fruit–Vegetable Juice Processing

This study aimed to isolate salt-tolerant pectinolytic bacteria from the rhizosphere of a salt marsh plant and utilize their pectinases for the clarification of detox juice preparation. Sixteen halophilic bacterial strains were isolated from the rhizospheric soil of Arthrocnemum macrostachyum. The isolates were screened for pectinase activity, and two strains, ASA21 and ASA29, exhibited the highest pectinase production in the presence of 2.5% NaCl, reaching 13.3 and 14.1 IU mL−1, respectively. The strains were identified as Bacillus paralicheniformis and Paenibacillus sp. by 16S rDNA sequencing and phylogenetic analysis. Growth kinetics and pectinase production studies revealed that both strains produced pectinase during the log phase, with ASA29 demonstrating higher growth and pectinase titers. The pectinase from ASA29 exhibited enhanced activity in the presence of 3% NaCl. The pectinases from both strains were applied for the clarification of detox juice prepared from beetroot, carrots, and apples. The use of 20 IU mL−1 pectinase from ASA29 for 2–3 h yielded > 96% juice with high total phenolic content and antioxidant activities. This study highlights the potential of salt-tolerant pectinolytic bacteria from the rhizosphere for biotechnological applications, particularly in the clarification of juices with high salt content.

Irrigation of rangeland soils with coal seam water - A lysimeter study on soil physico-chemical properties

Groundwater extracted from coal seams may be a resource for irrigation of land in areas with low rainfall, but the effect of this water on soil properties needs to be established. A lysimeter study was conducted using intact soil cores (0.75 m diameter, 1.4 m deep) of four different soil types (Sodic Vertisol, Calcic Solonetz, Haplic Solonetz and Xanthic Lixisol) from southern Queensland, Australia, to study changes in soil physical and chemical properties under accelerated rates of irrigation with coal seam (CS) water (electrical conductivity (ECw) of 3 dS/m, pH of 8.8, and a sodium adsorption ratio (SAR) of 100). Cores were also alternately irrigated with deionised water to simulate rainfall, and either lucerne (Medicago sativa L) or Rhodes grass (Chloris gayana Kunth.) where grown in the lysimeters. The soil surface was treated with stoichiometric rates of elemental sulfur (1.4 t/ha) and gypsum (2.5 t/ha) prior to every 450 mm CS water irrigation to minimise changes in SAR and pH. Three of the soils (Vertisol, both Solonetz) had low leaching fractions (≤ 0.1 %) due to their clay texture and were initially saline in the subsoil (ECse 1.4–4.4 dS/m). Irrigation with CS water resulted in a gradual increase in salt content (EC) and SAR throughout the soil profile, but pH was not increased due to surface-applied elemental sulfur. The Lixisol had a higher hydraulic conductivity and leaching fraction (6.7 %) due to is loamy texture – in this soil, accumulated salts could be leached and no increase in salinity or pH were measured. Despite an increase in SAR for this loamy soil, no structural degradation was observed, and it could be sustainably irrigated with up to 3200 mm CS water (with cumulative irrigation volume of 5400 mm). Hence, leaching fractions rather than soil chemistry are good indicators to identify soils suitable for irrigation with CS water that is saline, alkaline, and sodic.

ANALYSIS OF CHANGES IN COOLANT PARAMETERS IN THE PRIMARY CIRCUITS OF COOLING SYSTEMS OF LINEAR ELECTRON ACCELERATORS

For cooling and thermostatting of linear electron accelerators (LEAs), ordinary tap water from underground sources was used, which has a fairly significant salt content. During the operation of the LEA, as a rule, scale is deposited on the heating surfaces, in addition, process pipelines are clogged, which interferes with the efficient operation of the equipment, and in some cases leads to it’s damage. A study of the quality of both tap water and water from cooling systems was carried out. Conductivity and pH measurements were used for continuous monitoring. Elemental analysis of salts present in waters was performed by emission spectral analysis with inductively coupled plasma on the ICPE-9000 Shimazu spectrometer and mass spectrometric method. It is recommended to flush cooling systems with dilute nitric acid to stop the decrease in conductivity.

Revealing the Hygroscopic Behavior of Ultrahigh Nitrogen Content Cyclo‐Pentazolate Salts

AbstractThree representative cyclo‐pentazolate salts including N2H5+N5−, NH3OH+N5− and NH4+N5−, are highly favored for their ultrahigh nitrogen content (80–96%). However, their ambiguous nature has severely restricted the application exploration. Herein, the relationships between humidity and moisture content of salt were established by quantitative analysis. Among the three salts, the hygroscopic ability has the following order: NH3OH+N5−>NH4+N5−>N2H5+N5−. Especially in the range of 40% RH −60% RH, the NH3OH+N5− has a high sensitivity to water, and the absorbed moisture content can be as high as 20.8% at 60% RH. When the relative humidity exceeds 60% RH, the hygroscopic rate of NH3OH+N5− rises sharply, at 80% RH, NH3OH+N5− will absorb excess moisture and turns into liquid form. After treating NH3OH+N5− at 40% RH, the very sensitive friction sensitivity (FS) and impact sensitivity (IS) of dried NH3OH+N5− (FS=20 N, IS=2 J) will change into insensitive salt (FS>360 N, IS>40 J). The higher moisture content in NH3OH+N5−, the lower the thermal stability, its thermal decomposition temperature (103.22°C) is 3.24°C lower than that of dry salt (106.46°C) at 75% RH (moisture content is 30.2%). The other two salts N2H5+N5− and NH4+N5− have the similar properties. Molecular dynamics simulation was further applied to explain the strong hygroscopicity of salts.

Zwitterion Modification in Desalination Membrane for Rejecting Salt and Salt Ions in Brackish Water – A Mini Review

ABSTRACTDesalination membrane using zwitterion modification provides a significant opportunity to enhance excellent properties for rejecting salt and salt ions. The outstanding properties are designed by positive and negative charges attached to the membrane surface, including water permeability, salt permeability, fouling, and hydrophilicity of the membrane surface. The hydrophilic membrane, which is mentioned as one of the types of desalination membrane, presents the ability to repel salt and salt ions and pass the water. The modification of hydrophilic membranes is also affected by several factors, including water permeability, salt permeability, fouling of membrane surfaces, crossflow velocity, transmembrane pressure, and temperature. Regarding membrane modification, zwitterion has been applied for several ranges, such as the hemodialysis process, live cell imaging, antibacterial surfaces, and wound dressing. However, using a zwitterion modification membrane for desalinating water containing salt content, including brackish water, has yet to be developed. In addition, literature reviews related to polymer membranes for brackish water desalination have never been comprehensively documented. Thus, this review article addresses the zwitterion modification for desalination membranes, which can reject salt and salt ions in brackish water. Furthermore, the mechanism of zwitterion modification for desalination membranes has been presented. Finally, the challenge of zwitterion modification for desalination membranes has been evaluated to inspire insight for future studies.

Study on the mechanical property and durability of alkali-activated seawater and sea sand recycled aggregate concrete

This study investigates the potential of Alkali-Activated Seawater Sea Sand Recycled Aggregate Concrete (ASSRAC) as a novel sustainable construction material. By utilizing recycled aggregates from construction and demolition waste, seawater, sea sand, and alkali-activated materials such as fly ash and blast furnace slag, this innovative concrete aims to mitigate carbon emissions from cement production and optimize resource usage. The impact of recycled aggregate replacement rate, water-to-binder ratio, and sand type on the compressive strength of ASSRAC was examined through analysis of variance. Cylindrical axial compression and prism flexural tests were conducted to evaluate the long-term performance of ASSRAC under seawater immersion. The results indicate a decrease in compressive strength with higher recycled aggregate replacement rates and water-to-binder ratios, with recycled aggregates being the primary weak link. Additionally, increasing the water-to-binder ratio hampers hydration by diluting alkali activators, weakening polycondensation reactions. Under seawater immersion, ongoing reactions foster denser C-(A)-S-H structures, enhancing compressive strength and elastic modulus over time. Moreover, higher recycled aggregate replacement rates result in improved ductility, attributed to reactions between the old mortar on recycled aggregate surfaces and slag/fly ash at interfaces. For specimens immersed for 0 and 90 days, most theoretical models accurately predict results, except for the CEB-FIP model, which only accurately reflects the stress-strain curve at 180 days. The seawater-sea sand group's flexural strength initially exceeds that of the freshwater-river sand group due to accelerated early hydration, but this advantage diminishes over time due to high salt content.

Development and characterization of mesoporous silica-MgSO4-MgCl2 binary salt composites for low-grade heat storage in fluidized bed systems

Achieving nearly zero-energy buildings requires the efficient utilization and storage of renewable energy. Salt-hydrate-based thermochemical energy storage (TCES) systems are promising due to their high heat storage capacity and minimal seasonal heat loss. However, challenges remain in their commercialization and large-scale application. For instance, TCES systems using magnesium sulphate (MgSO4) provide low temperature lifts due to slow reaction kinetics. Incorporating deliquescent salts like magnesium chloride (MgCl2) can enhance sorption performance but may introduce stability issues such as agglomeration and decomposition. This study presents a novel binary-salt composite combining MgSO4 and MgCl2 within commercial mesoporous silica (CMS) to address these challenges and enhance overall performance. The binary-salt composite powder, with a particle size range of 150–300 μm, is well-suited for use in fluidized-bed reactors, where fast mass and heat transfer promote efficient moisture adsorption, prevent uneven temperature distribution, and reduce agglomeration. Thermogravimetric analysis (TGA) was employed to evaluate the water sorption and desorption behaviour of MgCl2-MgSO4@CMS binary-salt composites with a total salt content of 50 wt% and salt mixing ratios of 3:1, 1:1, and 1:3. The corresponding water sorption capacities were 0.95, 0.68, and 0.57 g/g, respectively. In comparison, the MgSO4@CMS single-salt composite showed a lower water adsorption capacity of 0.47 g/g and required temperatures exceeding 150 °C for complete regeneration. Reactor-scale experiments demonstrated that the MgCl2-MgSO4@CMS composite with a 1:1 salt mixing ratio could be fluidized at low gas velocities on the order of 10−2 m/s, achieving a maximum temperature lift of 24.7 °C and an energy density of 1018 kJ/kg during hydration at 80% relative humidity and 30 °C. Additionally, the binary-salt composite showed good cyclic stability with less particle agglomeration compared to the MgCl2@CMS single-salt composite.

Enhanced desalination performance of flow capacitive deionization with the addition of conductive polymer in redox couples and activated carbon

Freshwater scarcity is a critical global issue and desalination of brackish water and seawater technologies are regarded as effective solution to mitigate the increasing severity of water shortage. Flow-electrode capacitive deionization (FCDI) is an emerging electrochemical desalination technology capable of continuous deionization behavior. However, reducing energy consumption and enhancing desalination rate are now markedly needed for its advancement. Herein, we propose a FCDI system with energy consumption as low as 88.08 kJ mol−1 and a desalting rate of 1.75 μg cm−2 s−1. This is achieved by using flow electrodes containing 0.03125 wt% conductive polymer, 5 wt% activated carbon/carbon black and 80 mM/80 mM ferricyanide/ferrocyanide at a current density 3 mA cm−2 (3.36 mA current for a 1.12 cm2 active area). We further investigate the effects of polymer content, redox pair content, salt content and current densities on desalination performance. Seawater with a conductivity of 52.78 mS cm−1 was successfully desalinated to 0.50 mS cm−1 in continuous process. This research provides a promising approach to enhance FCDI system by achieving a low energy consumption and high salt removal rate, representing a significant advancement in continuous electrochemical desalination technology.

Optimization of Desalting Conditions for the Green Seaweed Codium fragile for Use as a Functional Food with Hypnotic Effects.

Codium fragile (CF) contains various bioactive compounds, but its high salt content (39.8%) makes its use as a functional food challenging. Here, we aimed to optimize the desalination process and verify changes in functionality based on variations in salt and total phenolic contents. To optimize the CF immersion conditions for the lowest salt content and monitor the total phenolic content, a response surface methodology was used. The optimal immersion conditions were as follows: X1 (immersion temperature) = 42.8 °C; X2 (immersion time) = 1.0 h. An inverse correlation was noted between salt content and total phenolic content. Among the post-desalination processes, desalination with centrifugal dehydration (CD) significantly reduced salt content. CD ethanol extract (CD-E) induced the longest sleep duration in the pentobarbital-induced sleep test in ethanol extracts. Moreover, 1000 mg/kg CD-E had a significant effect on non-rapid eye movement sleep but did not affect delta activity. These findings highlight the potential of industrializing CF as a functional food through desalination and its promise as a natural aid for sleep promotion.

An Effective Method for Quantitative Interpretation of Seawater Intrusion in Shallow Aquifers from Electrical Resistivity Data

Groundwater in coastal areas is vulnerable to saltwater intrusion. Electrical resistivity is commonly used in order to detect saltwater intrusion due to its ability to distinguish the occurrence of saltwater in the pore water. In this research, a correlational approach was used to estimate percentage seawater content that was mixed with fresh water in a shallow aquifer. The study area was located in Dumai City, which was covered mainly by peat soil, but some areas were covered by sand and silt. A ground surface resistivity survey and direct soil resistivity measurements were used in the study. For both experiments, the Wenner configuration of electrical resistivity was employed. In order to determine the direct soil resistivity values, measurements of the soil's fluid content and character were made. The findings indicate that the resistivity value in the aquifer increased to 5–10 Wm at a 25% seawater content, from roughly 2–5 Wm at a 50% seawater content. The pore soil's rising salt content was the primary source of the sharp decline in resistivity values. By measuring the electrical resistivity on the surface, it is possible to accurately forecast the percentage of seawater mixture in the pore soil fluid.

Enhancing salt-induced gelation of egg yolk granules through pH-ultrasound combined treatment: A physicochemical and microstructural analysis

Salted duck eggs are a popular food product, but their high salt content and uneven salt distribution can reduce acceptability. This study investigated the effects of pH-high-intensity ultrasound combined treatment on the salt-induced gelation properties of egg yolk granules. The results showed that the pH5 + 150 W treatment group exhibited the best physical and gelation properties, with the smallest particle size (1597.33 nm), optimal dispersibility (PDI 0.29), and good stability. The gelation properties of this group also demonstrated excellent springiness (0.30 mm), cohesiveness (0.56), and gumminess (0.05 N). Furthermore, the pH5 + 150 W group had the highest water holding capacity of 97.42 % and relatively high hydrophobicity (173.39 μg). Notably, it also showed high oil exudation (2.83 %) and good sandiness (62.07 %). The pH5 + 150 W led to a significant redshift of the fluorescence peak at 335 nm and an enhancement of the peak intensity at 562 nm compared to the control group. Structural characterization revealed a more ordered protein structure and a uniform gel structure with enhanced electrostatic repulsion between oil droplets. Secondary structure analysis of the proteins showed a significant reduction in α-helix and β-sheet, while β-turn and random coil increased. In summary, the pH5 + 150 W treatment displayed the best gelation properties, providing theoretical guidance for enhancing the processing performance of yolk and expanding their application in the food industry.

Studying the Influence of Salt Concentrations on Betalain and Selected Physical and Chemical Properties in the Lactic Acid Fermentation Process of Red Beetroot

This study emphasizes the significance of optimizing salt content during the fermentation of red beetroot to produce healthier and high-quality fermented products. It investigates the impact of different salt levels on fermentation, analyzing various parameters such as pH levels, dry matter content, total acidity, salt content, color changes, pigment content, and lactic acid bacteria count. This study identifies the most favorable salt concentration for bacterial growth during fermentation and storage as 2–3%. It was evaluated that salt levels fluctuated significantly during fermentation, with nearly 50% of the added salt absorbed by the beetroot tissues, mainly when lower salt concentrations were used. The fermentation process had a negative effect on the content of betalain pigments, as well as yellow pigments, including vulgaxanthin-I. It was also found that fermentation and storage affected the proportions of red pigments, with betacyanins proving to be more stable than betaxanthins, and that salt addition affected negatively pH and total acidity while causing an increase in yellow color. The pH was negatively correlated with the duration of the process, the amount of red pigment, and bacterial count. The results indicate that lower salt levels can lead to favorable physicochemical and microbiological parameters, allowing for the production of fermented red beetroot with reduced salt content without compromising quality.

Haute cuisine: A mixed-methods approach to assess gastronomic offer nutritional adequacy and importance given by chefs to food and nutrition guidelines

In recent years, a growing interest of society for out-of-home food experiences has been observed, concurrently with an increasing number of restaurants associated to haute cuisine. However, data on the nutritional adequacy of the meals offered in these restaurants is lacking. This study aimed to evaluate the perception of haute cuisine chefs in Portugal about the importance attributed to food and nutrition recommendations when planning their gastronomic offer and to assess the nutritional adequacy of the meals offered in these restaurants. A mixed-methods, cross-sectional study was conducted, in which all chefs from Michelin star-awarded restaurants in Portugal, in accordance to the Michelin Guide 2022 edition, were eligible and invited to participate. A qualitative content analysis of semi-structured face-to-face individual interviews (n = 11 chefs) and a quantitative assessment of the nutritional composition of appetizers, main courses and desserts (n = 29 recipes) were conducted between January and June of 2022. The majority of chefs reported giving much importance to nutrition principles while planning their menus, also showing positive attitudes and opinions towards healthy food practices and future partnerships with nutritionists. However, knowledge and perceptions regarding nutrition concepts were, in general, inconsistent and unobjective. Recipes' median energy contents ranged between 549 kcal/serving in meat courses and 1594 kcal/serving in desserts, with total fat contribution at around or above 40% of total energy value (TEV). Median saturated fat contents varied between 14% and 21% of TEV in appetizers and desserts, respectively. Sugar contents were the highest in desserts (median: 49% of TEV). Salt was particularly high in seafood dishes (median: 12.9 g/serving). The recipes evaluated showed an inadequate nutritional profile, with energy, total fat, sugar and salt contents frequently above maximum recommendations. Strategies aimed at improving chefs’ culinary practices are needed, namely through the enhancement of their literacy and awareness regarding nutrition principles. Their openness to collaborate with nutrition specialists should be exploited as an opportunity for future interventions.

Effect of succinonitrile on the structural, ion conductivity, and dielectric properties of PVDF‐HFP based solid polymer electrolytes

AbstractA detailed account of the poly(vinylidene difluoride‐co‐hexafluoropropylene) (PVDF‐HFP)/succinonitrile (SN)/lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) based solid polymer electrolytes (SPEs) of various compositions is reported. SN is incorporated as plasticizer, while LiTFSI is employed as the source of lithium ions. Fourier transfer infrared (FTIR) spectroscopy reveals the formation of polar and electroactive γ crystal phase by PVDF in pristine PVDF‐HFP and the prepared SPE films. FTIR further confirms the interaction between the host polymer and the salt and between the salt and the plasticizer. The interaction between the salt and plasticizer suggests that SN not only offers the plasticization effect but also facilitates salt dissociation. The ion conductivity increases with increasing salt content up to 20 wt% but beyond that concentration a decline in ion conductivity is observed, which could be attributed to the ion pair association or cluster formation due to the excess salt concentration that reduces the availability of free ions and ultimately leads to the reduction in ion conductivity. After including SN in the SPE formulation, electrochemical impedance spectroscopy reveals a substantial increase in room temperature ion conductivity of the SPE from ~1.08 × 10−5 S cm−1 for pristine SPE with 20 wt% salt to ~2.7 × 10−4 S cm−1 for plasticized SPE with 40 wt% SN and 20 wt% salt. This is attributed to the plasticizing effect of SN that enhances ion mobility through the matrix and to the increased charge carrier concentration (SN facilities salt dissociation). The fabricated SPEs exhibit a significant enhancement in ion conductivity with increasing temperature and the maximum ion conductivity of 1.1 × 10−3 S cm−1 is attained at 393 K by plasticized SPE with 40 wt% SN content. The ion conductivity of all the prepared SPEs follows the temperature dependent Arrhenius behavior, suggesting the thermally activated ion hopping mechanism of ionic conduction. Further, the plasticized SPEs display near unity ion transference number indicating the predominance of the ionic mode of conduction. The dielectric and electric modulus analysis reveal a faster relaxation phenomenon and hence higher ion conductivity of the prepared SPEs with increasing salt and plasticizer content.

Hydrochemical Characteristics and Formation Mechanism of Geothermal Fluids in Zuogong County, Southeastern Tibet

Zuogong County is located in the southeast of Tibet, which is rich in hot spring geothermal resources, but its development and utilization degree are low, and the genetic mechanism of the geothermal system is not clear. Hydrogeochemical characteristics of geothermal water are of great significance in elucidating the genesis and evolution of geothermal systems, as well as the sustainable development and utilization of geothermal resources. The hydrogeochemical characteristics and genesis of the geothermal water in Zuogong County were investigated using hydrogeochemical analysis, a stable isotope (δD, δ18O) approach, and an inverse simulation model for water–rock reactions using the PHREEQC. The results indicated that the Zuogong geothermal system is a deep circulation heating type without a magmatic heat source. The chemical types present in the geothermal water from the Zuogong area are HCO3 and HCO3·SO4, and the main cations are Na+ and Ca2+. The groundwater is replenished by atmospheric precipitation and glacier meltwater. The salt content of geothermal water mainly comes from the interaction between water and surrounding rocks during the deep circulation process. The reservoir temperature of geothermal water in Zuogong is 120–176 °C before mixing with non-geothermal water and drops to 62–98 °C after mixing with 58 to 79% of non-geothermal water. According to the proposed conceptual model, geothermal water mainly produces water–rock interaction with aluminosilicate minerals in the deep formation, while in shallow areas it interacts mainly with sulfate minerals. These findings contribute to a better understanding of the geothermal system in Zuogong County, Tibet.

A highly sensitive fluorescent sensor for reversible visual detection of fluoride ion and trace water in food products

A simple diphenylimidazole-based fluorescent sensor (DIP) had been designed for reversible fluorescence sensing of F− and trace water. The sensor showed superior selectivity for F− compared to other anions with fluorescence “turn on” mode. After adding F− to CH3CN solution of DIP, the emission color of DIP changed markedly from weak blue to strong cyan, which could be facilely discerned by the naked eye. The various technical analysis, including spectroscopies, 1H NMR titration and DFT calculation, indicated that the deprotonation of imidazole –NH and –OH occurred in the presence of F−. The detection limit of DIP toward F− could reach as low as 72.3 nM. Moreover, F−-induced deprotonation of DIP-F− system exhibited high sensitivity for water with the detection limit of 0.0015 vol%. The reversible switching characteristic of DIP prompted it suitable for the construction of molecular logic gate. In addition, DIP and DIP-F− were successfully applied to the determination of F− content in toothpaste and water content in table salt, sugar and tea, respectively. Moreover, DIP and DIP-F−-coated filter paper strips could be used as fluorescent display materials for inkless writing with repeatability.

Interferences of Adding High Salts Content Matrices to Cadmium Using Flame Atomic Absorption Spectrometry (FAAS) in Aqua Solution

Interferences of Adding High Salts Content Matrices to Cadmium Using Flame Atomic Absorption Spectrometry (FAAS) in Aqua Solution

Contextual and psychological factors in using recycled stormwater for residential purposes: a case study from Taiyuan, China

ABSTRACT This paper reviewed the managed aquifer recharge (MAR) practices around the world and explored urban residents' attitudes towards using stormwater recycled through MAR for residential uses in a Chinese socio-cultural context. The exploration was conducted from both contextual and psychological perspectives based on two established theories. The moderating effect of gender on residents' attitudes was tested. The results showed that most respondents supported using recycled stormwater for residential purposes but demonstrated hesitance in using recycled stormwater for uses that present proximity to human contact, which normally requires connecting the water to their house. Regarding the water quality attributes such as the colour, odour, and salt content of recycled stormwater, respondents were more tolerant if the water was used for uses that have limited human contact and less tolerant for uses that have close human contact. Therefore, any future decision to connect recycled stormwater into houses would require careful consideration and investigation as it depends on a range of issues including the proximity to human contact and the quality attributes of the water. Gender was a weak predictor in moderating respondents' attitudes towards using recycled stormwater, which adds to the inconsistent literature.