Primary Water Research Articles

Vegetation dynamics regulate baseflow seasonal patterns of the Chaohe watershed in North China

Study regionThe Chaohe watershed is Beijing's primary potable water source. Study focusThe initiation of ecological restoration (ER), combined with the rapid acceleration of climate change (CC), has precipitated severe water shortages in North China. The seasonal responses of baseflow (BF), pivotal for sustaining rivers' fundamental flow and ecological equilibrium, to ER and CC are poorly understood. This study provides a precise depiction of the seasonal variations in BF by leveraging multiple separation methodologies. By applying the BFAST algorithm and a comprehensive sensitivity analysis, we unveil the nuanced seasonal patterns of BF adjustments in reaction to ER and CC. New hydrological insights for the regionBaseflow, primarily influenced by the wet season, constituted 64.21% of the annual aggregate. Considerable decreases in BF during the dry (−32.61%) and wet (−68.21%) seasons pose increasing threats to available water resources. The decrease in sub-surface runoff (−1.91 mm per decade) dominated the reduction of dry season BF. Indeed, vegetation regulated seasonal water distribution, maintaining the essential flow throughout the dry season. In the wet season, the reduction in BF acts as a supplemental water source to fulfill the escalating evapotranspiration needs due to afforestation and a drying climate. This study highlights the persistent hydrological consequences of ER and CC on water resources, emphasizing the crucial function of vegetation in baseflow, a key component for ecological restoration and water resource management in water-limited areas.

Study on Water Quality of Sekadau River Using Pollution Index Method

One of the leading causes of declining water quality is contamination from human activities. The Sekadau River serves as a primary water source for the residents of Sekadau Regency, facilitating bathing, laundry, kitchen equipment cleaning, and freshwater fish cultivation. The objective of this study is to evaluate the water quality of the Sekadau River, comparing it against Class II standards as stipulated in Government Regulation No. 22 of 2021 on Environmental Protection and Management. Subsequently, pollution levels in the Sekadau River at the measurement point were determined using the Pollution Index Method (PIM). The research findings reveal that the pollution index values for 2018, 2022, and 2023 fall within the lightly polluted category. Conversely, in 2019, the water quality of the Sekadau River exhibited improvement. It complied with water quality standards per the Minister of Environment and Forestry Decree No. 115 on Quality Status Determination Guidelines. Consequently, the Sekadau River remains suitable for bathing, laundry, freshwater fish cultivation, and other purposes requiring water of the same quality as its designated use. However, considering the increasing pollution trends in 2022 and 2023, appropriate measures are necessary to prevent the Sekadau River from becoming more polluted.

The Effect of Content Marketing on Purchase Intention Mediated by E-Wom (Empirical Study: Ice Cream Consumers on Klik Indomaret)

The purpose of this study is to analyze the effect of content marketing on purchase intention. The benefit of this study is to find out what factors influence purchase intention because it is important for ice cream manufacturers to develop online sales market share. This research method is a quantitative research method with survey methods, which is a research method to examine certain types of content by collecting primary water through the use of research instruments that are structured and systematical with the aim of testing hypotheses that have been studied. There is a positive relationship between eWOM and consumers and businesses. The formation of eWOM is the result of the company's performance in Maisai Lailu and encourages company performance in the future. eWOM is an important source of acquisition through various digital markets so that eWOM has the ability to achieve consumer acquisition, consumer retention and consumer acquisition'. Based on the results of research and discussions that have been carried out, the conclusions that can be drawn are as follows: Content marketing has a significant positive effect on purchase intention in consumers of Klik Indomaret ice cream received Content marketing has a significant positive effect on e-wom in consumers of Klik Indomaret ice cream received. E-wom has a significant positive effect on purchase intention in consumers of Klik Indomaret ice cream received. E-wom mediates the effect of content marketing on purcahase intention in consumers of Klik Indomaret ice cream received

Genesis of the eastern Barents Sea part water masses using winter data of isotopic parameters δ18O and δ2H

The study aims to evaluate the shares of primary waters (Atlantic, river, meltwater, and sea water withdrawn for ice formation) in the resulting water masses in the eastern part of the Barents Sea at the end of the hydrological winter. Moreover, the study compares the outcomes achieved by using salinity-δ18O and salinity-δ2H values.The study was based on the data on water temperature and salinity and δ18O and δ2Н stable isotopes values. We implemented field studies in March and April 2021 at the Dalnie Zelentsy research vessel, providing the only known and available source of data on δ18O and δ2Н for the eastern part of the Barents Sea between 70⁰ N and 79⁰ N at the end of the hydrological winter. The results allow for estimating the shares of the primary waters, namely Atlantic, river, meltwater, and sea water, withdrawn for ice formation in the sea water during this period of the year in various water masses meltwater. Moreover, they allow for estimating the influence of each of the primary waters on the salinity of the resulting water masses. However, when we calculate the average Atlantic and ice water shares using the δ2H isotopic parameter, they are somewhat higher than those calculated using δ18O. Conversely, the river water share is somewhat lower.A 0.36 psμ (0.34–0.51 psμ) change (decrease) in salinity in the Atlantic water mass is due to mixing with river waters and 0.04 psμ (−0.05 to 0.10 psμ) with mixing with meltwater. In the Barents Sea winter water mass these values are 0.63 (0.53–0.71 psμ) and 0.31 (0.27–0.42 psμ), respectively. In the water mass called ‘Surface waters of the Arctic seas, winter’, the processes of ice formation prevail over the processes of ice melting. The average decrease in salinity due to the content of river waters alone could be 0.66 psμ (0.59–0.74 psμ). However, it is only 0.46 psμ (0.41–0.57 psμ) due to salinisation during ice formation.The quantities of meltwater volumes and volumes of water withdrawn for ice formation serve as specific characteristics of «memory», describing the ice formation/ice melting processes.

Remove legacy perfluoroalkyl acids and emerging per- and polyfluoroalkyl ether acids by single-use and regenerable anion exchange resins: Rapid small-scale column tests and model fits

Rapid small-scale column tests (RSSCT) are used to study the removal of per- and polyfluoroalkyl substances (PFAS) for drinking water treatment by ion exchange. Breakthroughs of 15 emerging per- and perfluoroalkyl ether acids and six legacy perfluoroalkyl acid analogs are studied using a single-use PFAS-selective anion exchange resin (AER1) and a regenerable, generic anion exchange resin (AER2). The Bohart-Adams model was used to describe and predict breakthrough, with the modeled results reasonably aligned with RSSCT results in most cases, enabling shorter RSSCT duration for future applications. AER1 exhibited high uptake capacity with no breakthrough for 11 of the 21 tested PFAS during the 144,175 BV continuous operation, allowing compliance with the new National Primary Drinking Water Regulation in many application scenarios. AER2 exhibited much faster breakthroughs for most PFAS and is not a promising option for drinking water treatment. However, the summed PFAS capacity via model fit and total PFAS adsorbed via measurement were only <0.01 % of both resin capacities at full breakthrough, suggesting PFAS could only occupy a tiny portion of the ion exchange sites even for the PFAS-selective AER1. Ether group insertion in the PFAS group leads to later breakthrough, and linear isomers were better captured by the resins than the branched isomers. Overall, PFAS uptake capacity increases and kinetics decrease when the PFAS molecular volume increases. Regeneration using 10 % NaCl solutions partially released PFAS from AER2 but not from AER1, with more short-chain PFAS released than long-chain ones. Ether group insertion decreased the PFAS recoveries during the regeneration of AER2. The regenerated resins showed much faster breakthroughs than the pristine resins, making them unfavorable for drinking water treatment applications. Adsorption displacement of short-chain PFAS by long-chain PFAS was observed in pristine AER1, and post-regeneration leaching occurred for both resins, both phenomena making the resins a possible PFAS source in long-term use.

EVALUATION OF NGABEAN SECONDARY CANAL IRRIGATION NETWORK, NGAWI DISTRICT PART OF SALURAN INDUK MADIUN IRRIGATION AREA

The SIM Irrigation Area has an area of 10,860 Ha and a primary canal length of 27,022 m, which passes through the Regencies of Madiun, Magetan, Ngawi, and Madiun City. One of the secondary canals in the D.I SIM is the Ngabean Secondary Canal, located in Ngawi Regency. This canal receives the main water supply from Jati Dam, 25% of the primary dam discharge and water withdrawal from the Ngabean Dam intake of 0.45 m3/ha. However, this value only meets the water needs of some of the irrigation areas. Due to the limited supply from the Jati Bendung, the government is working on rehabilitation work at the Jati Bendung. Apart from that, the Ngabean Secondary Canal also experienced a reduction in the irrigation area from 1840 ha to 1818 ha, to be precise in the NG3 Ki tertiary plot, which had an initial area of 120 ha to 98 ha. Therefore, an evaluation of the Ngabean Secondary Canal is needed to determine the value of water demand, water availability before and after rehabilitation and land reduction, and increasing agricultural profits.From the results of the analysis that has been carried out, it was concluded that the highest dependent flow at Ngabean Dam was 5.00 m3/s, and the lowest was 0.01 m3/s. Meanwhile, in conditions before rehabilitation, the highest dependent flow of Jati Dam was 1.01 m3/s, and the lowest was 0.00 m3/s with water withdrawal at the intake of 25%, able to fulfill the planting pattern of paddy (15%)-crops (75%)-crops (50%) generated a production profit of IDR 8.794.123.880,00. Meanwhile, after rehabilitation, the highest was 5.93 m3/s, and the lowest was 3.21 m3/s with an intake of 32%, able to fulfill the planting pattern of paddy (100%)-paddy (100%)-paddy (100%), resulting in a production profit of IDR 83, 564,115,480.00 with the highest irrigation water requirement value of 3.10 m3/sec. Apart from that, the existing canal dimensions still meet the requirements after land reduction, so no changes to the canal dimensions are required.

Effect of water vapor transport and budget on precipitation in the Yangtze–Huang–Huai–Hai River Basin

Study regionThe Yangtze−Huang−Huai−Hai River basin (3.19 million km2) in China, which is vital for China's economic development. Study focusWe employed the Eulerian method to identify the primary water vapor channels from 2005 to 2020, and the water vapor net budget over the basin was calculated. Additionally, the Lagrangian method was utilized to simulate water vapor transport trajectories across four seasons, with the aim of investigating the influence of changes in water vapor on precipitation. New hydrological insights for the regionUtilizing both Eulerian and Lagrangian methods, the findings indicate that: (1) Precipitation in the basin experienced a downward trend of −3.5 mm·a−1 during 2005−2020, mainly in spring (−1.4 mm·a−1) and summer (−1.7 mm·a−1); (2) The water vapor net budget has a substantial downward trend (−0.9 kg·m−1·s−1·a−1), mainly in spring (−0.4 kg·m−1·s−1·a−1) and summer (−0.3 kg·m−1·s−1·a−1), which aligns with the declining trend of precipitation. (3) The Hybrid Single Particle Lagrangian Integrated Trajectory Model demonstrates that the decrease in long−distance water vapor transport trajectories impacts the basin’s water vapor channels. The decline in spring is predominantly influenced by the water vapor transport trajectories from Asia, Europe, and Africa−Arctic Ocean (−0.7 %·a−1), while the summer is mainly driven by the water vapor transport trajectory from the Indian Ocean−South China Sea (−0.3 %·a−1). This study improves the existing understanding of the hydrological cycle in the context of the basin, and offers a crucial scientific basis for water resource management and regulation.

Fretting corrosion behavior of a Cr-coated Zr-1Nb alloy cladding in simulated PWR primary water environment

The fretting corrosion behaviors of Cr-coated Zr‐1Nb alloy claddings with Zr-4 dimple and Inconel 718 spring in simulated PWR primary water were investigated. The results indicated that by increasing the fretting duration from 192 to 427 h, the maximum wear depth and volume of Cr coating with dimple increased by 15% and 3%, respectively. In the case of spring as a grinding material, however, the maximum wear depth and volume significantly increased by about 8 and 300 times, respectively. At 427 h, the Cr coating was worn through, and oxidation of the underlying Zr‐1Nb substrate formed a dual-layered oxide film.

Corrosion Mechanism and Electrochemical Reactions on Alloy 690 in Simulated Primary Coolant of Water-Water Energy Reactors.

During the power operation of the primary loop of a water cooled-water moderated energy reactor (WWER), the water chemistry evolves from a high-boron high-potassium composition to significantly lower concentrations of both constituents at the end of a campaign, and the Li concentration reaches ca. 0.7-0.9 ppm. In the present paper, the effect of primary water chemistry evolution during operation on the corrosion rate and conduction mechanism of oxides on Alloy 690 is studied by in situ impedance spectroscopy at 300 °C/9 MPa during 1-week exposures in an autoclave connected to a re-circulation loop. At the end of exposure, the samples were anodically polarized at potentials -0.8 to -0.1 V vs. SHE to evaluate the stability of the passive oxide. Simultaneously exposed samples of Alloy 690 were subsequently analyzed by XPS to estimate the thickness and in-depth composition of oxides. Impedance data were quantitatively interpreted using the mixed-conduction model (MCM) for oxide films. The effect of water chemistry evolution on the corrosion rate and conduction mechanism in the oxide on Alloy 690 in a primary coolant is discussed based on the obtained parameters.

Antifouling performance enhancement of PES membranes using hydrophilic nanoparticles of poly(dopamine-acrylate) for oil/water separation

Polydopamine-acrylate (P(A-D)x) nanoparticles were blended with polyethersulfone (PES) to fabricate a high-performance hybrid ultrafiltration (UF) membrane for the separation of water from oily wastewater. In tris-alkaline buffer solution at room temperature, P(A-D)x nanoparticles were synthesized by intramolecular Michael addition of dopamine with acrylic acid (AA) monomers. Hybrid PES membranes were prepared using P(A-D)x at 0.05–0.4 wt% and characterized using various assays including Field emission scanning electron microscopy (FESEM), Thermogravimetric analysis (TGA), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and water contact angle (WCA). The membranes showed a significant increase in hydrophilicity, water permeability, and oil rejection (R). The primary and secondary pure water fluxes of the membrane with 0.2 wt% P(A-D)0.25 were 45% and 110.78% higher than those of neat PES membrane, respectively. For 3300 ppm oil feed solution, water flux during water/oil separation increased by 107%, while the oil rejection (R) remained at 99.08%. The surface of membrane was markedly hydrophilic, with a WCA about 40°, much lower than that of the neat PES membrane (80.67°). UF hybrid membranes also showed a remarkable reduction in oil adhesion on the membrane surface as well as superior antifouling performance for membranes containing 0.2 wt% P(A-D)0.25, flux recovery ratio (FRR) = 84.88 ± 3.27%, reversible fouling (Rr) = 51.12 ± 1.09%, and irreversible fouling (Rir) = 15.12 ± 3.27%. In addition, the pure water flux was 446% higher than that of the unmodified membrane after five cycles (900 minutes).

Large scale water yield assessment for sparsely monitored river basins: A case study for Afghanistan

This paper presents results from a study on water yield assessment across five major river basins of Afghanistan. The study was conducted using GR4J and GR4JSG precipitation-runoff models. The river basins were divided into 207 subcatchments and each subcatchment was divided into multiple functional units. The model was calibrated using observed streamflow data from 2008 to 2015 and validated over the 2016 to 2020 period. Model parameters were calibrated for an unregulated subcatchment in each basin and calibrated parameters from the best-performing subcatchment were transferred to other subcatchments. Results show that modelled water yield across the five basins varies from 0.3 mm in the Helmand basin to 248 mm in the Panj-Amu basin, with an average of 72.1 mm for the entire country. In the period of 2008 to 2020, area averaged water yield in the five basins varies from 36 to 174 mm. For the same period, mean annual precipitation for the entire country is 234.0 mm, indicating a water yield of 30.8%. The nation-wide average water yield of 72.1 mm is equivalent to 46.3 billion cubic meters (BCM) of surface water for the country. In addition, about 28.9 BCM generates annually in the neighbouring Tajikistan and Pakistan from snow and glaciers of the Hindu-Kush mountains. The elevated northern parts of Afghanistan, including parts of neighbouring Tajikistan are the primary water source. Water yield across the country varies between years but there is no consistent increasing or decreasing trends. About 60 to 70% of flow occurs between March to June. The study identified the high water yield areas and investigated variability at monthly, seasonal, and annual time scales. An importance finding is the large spatial and temporal variability of water yield across the basins. This information is crucial for long-term water resources planning and management for agricultural development.

MnO2-based capacitive system enhances ozone inactivation of bacteria by disrupting cell membrane

The application of ozone (O3) disinfection has been hindered by its low solubility in water and the formation of disinfection by-products (DBPs). In this study, capacitive disinfection is applied as a pre-treatment for O3 oxidation, in which manganese dioxide with a rambutan-like hollow spherical structure is used as the electrode to increase the charge density on the electrode surface. When a voltage is applied, the negative-charged microbes are attracted to the electrodes and killed by electrical interactions. The contact between microbes and capacitive electrodes leads to changes in cell permeability and burst of reactive oxygen species, thereby promoting the diffusion of O3 into the cells. After O3 penetrates the cell membrane, it can directly attack the cytoplasmic constituents, accelerating fatal and irreversible damage to pathogens. As a result, the performance of the capacitance-O3 process is proved better than the direct sum of the two individual process efficiencies. The design of capacitance-O3 system is beneficial to reduce the ozone dosage and DBPs with a broader inactivation spectrum, which is conducive to the application of ozone in primary water disinfection.

Fractography of Stress Corrosion Cracking of 20% Cold Worked Type 304 H Stainless Steel Containing δ-Ferrite in Oxidizing Primary Water

Fractography of stress corrosion cracking (SCC) of 20% cold worked Type 304 H stainless steel containing δ-ferrite was studied using a compact tension (CT) specimen in oxidizing primary water with a scanning electron microscope (SEM) and electron back scattered diffraction (EBSD). The stress corrosion crack propagated mostly in transgranular stress corrosion cracking (TGSCC) mode and sometimes in intergranular stress corrosion cracking (IGSCC) mode. TGSCC paths were along the {111} plane with both high resolved shear stress and high resolved tensile stress. IGSCC preferentially propagated along the grain boundary perpendicular to the loading axis. The findings in this work suggest that TGSCC proceeds through formation of a weakening zone at the head of the crack tip by interaction of slip and corrosion and then cracking of the weakened zone by tensile stress.

Characteristics of 3D Printed Functionally Graded Material for Replacement of Dissimilar Metal Weld in Nuclear Reactor

The dissimilar metal welds in the most of the reactors are connections between low alloy steel parts and stainless steel piping. There is a high possibility of primary water stress corrosion cracking (PWSCC) damage attributed to residual stress caused by the difference in material properties in the dissimilar metal weld joints. A number of accidents such as leakage of radioactive coolant due to PWSCC have been reported around the world, posing a great threat to nuclear safety. The objective of this study is to develop a technology that can fundamentally remove dissimilar metal welds by replacing the existing dissimilar metal parts with the functionally graded material (FGM) manufactured by metal 3D printing consisting of low alloy steel and austenitic stainless steel. A powder production, mixing ratio calculation, and metal 3D printing were performed to fabricate the low alloy steel-stainless steel FGM, and microstructure analysis, mechanical properties, and coefficient of thermal expansion (CTE) measurement of the FGM were performed. As a result, it is observed that CTE tended to increase as the austenite content increased in FGM. The gradual change of coefficient of thermal expansion in a FGM showed that the additive manufacturing using 3D printing was effective for preventing an abrupt change in thermal expansion properties throughout their layers.

Geochemistry of hydrothermal illitizations in Eocene Kösedağ magmatic rocks, Zara-Suşehri area, NE Sivas, East-Central Anatolia: Origin and age of alteration

The study area located at the periphery of the collision zone between the Eurasian plate (i.e. Pontides) and Tauride-Anatolide platform, NE of Sivas in the east-central Turkey, which is part of the Tethyan Metallogenic Belt. Mixed-layer illite-smectite (IS) and illite minerals are derived within the hydrothermal alteration zones with a few km2 surface areas (up to 30 km2) in Eocene volcanic and plutonic rocks. The representative IS and illite samples taken from plutonic- and volcanic-hosted alteration zones are investigated by optical and scanning electron microscopy (SEM), X-ray diffraction (XRD), major and trace elements and OH isotope geochemistry and KAr dating methods. Different types of hydrothermal alterations, such as propylitic and phyllic alteration in the plutonic rocks and argillic alteration in the volcanic rocks were developed as a result of intrusion of Kösedağ Pluton (syenite) into Karataş Volcanics (basaltic trachy-andesite and trachyte) with relations of hot-hot contact. The main phyllosilicate/clay minerals are characterized by kaolinite and IS in volcanic-hosted argillic alteration zones, whereas IS and illite in plutonic-hosted phyllic zones. The ordering types (Reichweite) of IS and illites are represented by R1 IS (I = 65–80 % in IS) + R3 IS (I = 90 % in IS) in the volcanic-hosted rocks, and R3 IS (I = 90 % in IS) and illite (S = 3–5 %). Dioctahedral (d060 ≤ 1.500 Å) R3 IS and illites have 1 Md + 1 M and 1 Md + 1 M + 2 M1 polytypes, respectively. The major and trace elements such as TiO2, Fe2O3, MgO, Na2O, P2O5, Sc, V, Cu, Ge, Sr, Hf, Zr and Y increase in the volcanic-hosted IS, whereas SiO2, Al2O3, K2O, Pb, W, Mo, As, Sb, Rb and U in the plutonic-hosted IS and illites. The chondrite-normalized distributions of IS and illites present a great similarity to those of host rocks. The chondrite-normalized rare earth element (REE) concentrations are more enriched in the volcanic-hosted IS in comparison with the plutonic-hosted IS and illites having distinctive Eu negative anomaly, which indicate deriving from volcanic matrix and K-feldspar, respectively. Oxygen and hydrogen isotope data of illitic clays indicate that the hydrothermal fluids are originated from magmatic water. According to stable isotopes and fluid inclusion data, IS and illites were formed at the temperature conditions ~150 °C in volcanic-hosted argillic zone, whereas ~250 °C in plutonic-hosted phyllic zones. KAr dating of alunite, IS and illite minerals indicate that the hydrothermal alteration was started at 40.45 ± 1.28 Ma, almost 2 Ma after the Q-syenite intrusion, within the plutonic body as phyllic alteration stage, and continued up to 35.27 ± 2.81 Ma, with a duration of ~5 Ma, and finalized before the exhumation of the Kösedağ Pluton (28–30 Ma). The geochemical characteristics of IS and illites were controlled by host-rock, condition, origin, and ages of alterations and they can be used as an important tool for magmatic-hydrothermal systems.

Exploring potential trade-offs in outdoor water use reductions and urban tree ecosystem services during an extreme drought in Southern California

In Southern California cities, urban trees play a vital role in alleviating heat waves through shade provision and evaporative cooling. Trees in arid to semi-arid regions may rely on irrigation, which is often the first municipal water use to be restricted during drought, causing further drought stress. Finding a balance between efficient water use and maintaining tree health will be crucial for long-term urban forestry and water resources management, as climate change will increase drought and extreme heat events. This study aimed to quantify how urban tree water and carbon fluxes are affected by irrigation reductions, and how that relationship changes with tree species and temperature. We used an ecohydrologic model that mechanistically simulates water, carbon, and energy cycling, parameterized for 5 common tree species in a semi-arid urban area. We simulated a range of irrigation reductions based on average outdoor water use data from the city for a recent extreme drought as well as with warmer temperatures. We then analyzed the response of model outcomes of plant carbon fluxes, leaf area index (LAI), and water use. Results show that reducing irrigation up to 25%, a comparable amount as the California state mandate in 2014, has minimal effects on tree primary productivity and water use efficiency. We found that transpiration was linearly related to irrigation input, which could lead to a short-term loss of evaporative cooling with irrigation reductions during drought. However, primary productivity and LAI had a nonlinear response to irrigation, indicating shade provision could be maintained throughout drought with partial irrigation reductions. Results varied across tree species, with some species showing greater sensitivity of productivity to both irrigation reductions and potentially warmer droughts. These results have implications for water resources management before and during drought, and for urban tree climate adaptation to future drought.

Microscopic occurrence of primary water in carbonate gas reservoirs with fractures and vugs and its effect on water invasion mechanism

The structure of carbonate gas reservoirs has multiple pore-fracture cave media, and the gas–water flow mechanism is complex. Computed tomography (CT) and nuclear magnetic resonance (NMR) were used to explore the pore structure differences and collocation relationships of different small-scale carbonate cores with fractures and holes in the Longwangmiao Formation. Based on the concept of fractal dimensions, a quantitative method for water film occurrence was established, combined with surface wetting physics and mechanics. The formation of primary irreducible water and the influence mechanism of the water film on water invasion flow were clarified, the mechanical control mechanism of gas–water flow was analysed from the microelement structure, and the difference in water invasion in different pore structures was proven. This study showed that the bound water in carbonate rocks is controlled by micromechanics and occurs in the reservoir space through four mechanisms. Under the action of intermolecular forces and linear tension, a small amount of water film is formed as a movable pore surface, a small amount of pore edge space exists in the form of a corner because of the uneven rough pore surface, and a small amount exists in pores with pore diameters less than the critical pore diameter to form filling. Numerous pores occurred in isolated pores coordinated only by pores smaller than the critical pore size. Furthermore, the flow of the intrusive water phase is controlled by micromechanics such as the displacement force, viscous force of the water film layer on the pore wall, and the capillary force, which mainly occurs in connected pores and fractures larger than the “critical pore diameter of water invasion.” The “critical pore diameter” of the Longwangmiao formation ranges from 2.2 μm to 3.4 μm, and only the pores coordinated by small pores below the “critical pore diameter of water invasion” cannot be affected by the intrusive water phase due to the action of “pore resistance.” To form residual gas.

Understanding the role of storage reserve mobilization during seed germination and initial seedling growth in species of the genus Carapa

A physiological and metabolic database for various species of Amazonian plants is crucial to the species selection and sustainable utilization of their diversity. We hypothesized that understanding the mobilization of Carapa seed reserves and water uptake during germination could provide insights into the physiological behavior and propagation to differentiate species of the same genus. Given this, the mobilization mechanisms of primary reserves, water uptake, and enzymatic activities in seeds of two species of Carapa (C. guianensis and C. vasquezii) were investigated. The lipid content was high in both species, with a value of 63.7±4.7% for C. guianensis and 55±1.5% for C. vasquezii. C. guianensis showed higher values for the other evaluated reserves. The protein profile highlights a band between 15 and 25 kDa in C. guianensis. As for the enzymatic activities investigated (lipase, amylase, protease, acid phosphatase), C. guianensis showed greater activity for most of them, except for acid phosphatase. Overall, the species showed different metabolic strategies and dynamics regarding the water uptake and use of reserves. Our findings indicate that distinct metabolic pathways are employed during the germination and initial seedling growth stages of two Carapa species. This trait can potentially guide the use and preservation of these species.

Public Health Risks of PFAS-Related Immunotoxicity Are Real.

The discovery of per- and polyfluoroalkyl substances (PFAS) in the environment and humans worldwide has ignited scientific research, government inquiry, and public concern over numerous adverse health effects associated with PFAS exposure. In this review, we discuss the use of PFAS immunotoxicity data in regulatory and clinical decision-making contexts and question whether recent efforts adequately account for PFAS immunotoxicity in public health decision-making. Government and academic reviews confirm the strongest human evidence for PFAS immunotoxicity is reduced antibody production in response to vaccinations, particularly for tetanus and diphtheria. However, recent events, such as the economic analysis supporting the proposed national primary drinking water regulations and clinical monitoring recommendations, indicate a failure to adequately incorporate these data into regulatory and clinical decisions. To be more protective of public health, we recommend using all relevant immunotoxicity data to inform current and future PFAS-related chemical risk assessment and regulation. Biological measures of immune system effects, such as reduced antibody levels in response to vaccination, should be used as valid and informative markers of health outcomes and risks associated with PFAS exposure. Routine toxicity testing should be expanded to include immunotoxicity evaluations in adult and developing organisms. In addition, clinical recommendations for PFAS-exposed individuals and communities should be revisited and strengthened to provide guidance on incorporating immune system monitoring and other actions that can be taken to protect against adverse health outcomes.

Stress-corrosion cracking sensitization by hydrogen upon oxidation of nickel-base alloys by water – An experiment-guided first-principles study

This work describes a viable hydrogen-induced sensitisation process toward stress corrosion cracking in chromia-forming nickel base alloys owing to oxidation by water. A mechanistic chemical understanding of the stress corrosion based on repeated cracking and re-healing of the oxide scale emerges from experiment-guided first-principles calculations. Piggybacking processes during repeated oxide scale cracking-healing cycles are understood to cause sensitisation towards the formation and growth of macroscopic cracks. Under light-water reactor conditions, the healed oxide scale comprises an outer region composed of chromium depleted nickel ferrite, and non-protective chromia, nickel oxide, and nickel hydroxide. An inner nickel iron chromite layer provides the passivating barrier that controls the oxidation rate at a steady state. Early during the re-healing of a crack in the oxide scale, water is conveyed to the alloy/scale interface by hydration/dehydration of composite nickel oxy-hydroxide Ni(OH)2∙NiO inclusions in the scale. At later stages, Ni(OH)2∙NiO serves as oxidant of preferentially chromium, while hydrogen is released as H2(g) into the primary water or becomes picked up by the alloy, possibly while assisting in the reduction of NiO to form nickel metal particles. Oxidation by water equivalents at the confining alloy/oxide scale interface favours hydrogen pick-up in the alloy that becomes increasingly detrimental owing to enrichment and inward diffusion of hydrogen along alloy grain boundaries. The pinning of alloy vacancies by hydrogen causes mitigation of outward diffusion of chromium, which in turn hampers crack re-healing while promoting alloy embrittlement.