High Temperature Water Research Articles

Hindcasting Farmed Salmon Mortality to Improve Future Health and Production Outcomes.

Intracellular, free-floating and biofilm-forming bacterial pathogens have been implicated in summer mortality of farmed Chinook salmon, Oncorhynchus tshawytscha, in New Zealand. A mortality event in 2022 in the Pelorus Sound, Marlborough, was linked to high water temperatures (> 18°C), and bacterial skin disease associated with Piscirickettsia spp. (=Rickettsia-like organisms) and Tenacibaculum species. To understand the progression of infection and potential drivers of the mortality, simulation of the event was conducted using a networked susceptible, infectious and recovered (SIR) model. Parameter exploration shows that reconstruction of observed mortality rates across three affected farm sites was possible. The best SIR simulations identified plausible values for key drivers of disease, which are consistent with previously estimated disease parameter ranges for Piscirickettsia salmonis. Our modelling shows the 2022 Pelorus Sound event likely experienced spread of bacterial pathogens within healthy fish populations at salmon farm sites over a 10-week long incubation period, before elevated mortality was observed. We show evidence that vaccine use at one site likely prevented 10% higher mortality and that an alternative site for the vaccination could have further reduced mortalities. This result highlights the importance of future vaccine developments in aquaculture and the potential to improve vaccine efficacy through considered site selection.

Engineering Subnanometric Electronic Interaction between Ru and Mn in Zeolite Boosts Catalytic Oxidation of Dichloromethane.

Designing catalysts with both activity and stability remains a grand challenge for the removal of chlorinated volatile organic compounds (CVOCs) by catalytic oxidation. Herein, the Ru-Mn subnanometric species encapsulated in ZSM-5 zeolite (RuMn@Z) was synthesized. It shows that the 90% conversion of dichloromethane is as low as 320 °C, which is significantly lower than that of Ru@Z (350 °C) and the impregnation catalyst (RuMn/Z, 355 °C). Importantly, the RuMn@Z catalyst exhibits excellent high-temperature resistance (800 °C for 10 h), water resistance, long-term stability, and cyclic stability. Different from the RuMn/Z with nanoscale metal interaction, Ru and Mn species in RuMn@Z have strong electronic interaction on the subnanometric scale due to the confinement effect of zeolite. As the electronic structure regulator, the Mn species keeps the Ru species in an electron-deficient state through the Ru-O-Mn bonds, which effectively activates lattice oxygen species and molecular oxygen to participate in the reaction. Moreover, the confinement effect also makes the acid tightly coupled with the redox site, which promotes the rapid conversion of dechlorination products, formates, and other intermediate products. Therefore, this study provides valuable insights into the design of high-performance catalysts for CVOCs removal and other environmental fields.

Corrosion Resistance of Alloy 690 in High-Temperature Water with Various Dissolved Hydrogen Concentrations

Corrosion Resistance of Alloy 690 in High-Temperature Water with Various Dissolved Hydrogen Concentrations

Role of residual stress and ultrafine grain layer at the surface introduced by water jet cavitation peening in stress corrosion cracking of alloy 600 in high temperature water

Role of residual stress and ultrafine grain layer at the surface introduced by water jet cavitation peening in stress corrosion cracking of alloy 600 in high temperature water

Comparative corrosion behavior of Alloys 690 and 800 in high-temperature water: Combined effects of polyacrylic acid and dissolved oxygen

Comparative corrosion behavior of Alloys 690 and 800 in high-temperature water: Combined effects of polyacrylic acid and dissolved oxygen

Effects of pH on the corrosion behavior of 316L SS in SMRs for boron-free lithium-containing high-temperature water: Experiments and calculations

Effects of pH on the corrosion behavior of 316L SS in SMRs for boron-free lithium-containing high-temperature water: Experiments and calculations

Preparation and Properties of Iron Tailings-Fly Ash Based Geopolymers

Iron tailings are the main component of industrial solid waste. The long-term storage and landfill of iron tailings have caused great pressure on the environment. In this paper, Anshan type high-silicon iron tailings and fly ash were used as the main raw materials to prepare geopolymer. The activity of raw materials was determined by XRD, and geopolymer was prepared by high temperature water culture. The effect of iron tailings content, liquid-solid ratio and curing temperature on geopolymer mechanics was studied. The optimal ratio was determined by regression equation analysis with compressive strength as index. The reaction process of geopolymer was studied through microscopic analysis (XRD, SEM, FTIR), and the changes before and after the reaction of geopolymer were compared to prove the reaction degree of geopolymer, and representative specimens were selected to verify the strength changes under different ratios. The durability of the prepared polymers was tested, and the relevant parameters were determined. The gelling material with good freezing resistance and chemical corrosion resistance was successfully prepared, and the industrial waste was transformed into treasure.

Evaluation of Coal Repowering Option with Small Modular Reactor in South Korea

The Paris Agreement emphasizes the need to reduce greenhouse gas emissions, particularly from coal power. One suggested approach is repowering coal-fired power plants (CPPs) with small modular reactors (SMRs). South Korea plans to retire CPPs in the coming decades and requires alternative options for coal-fired energy. This study presents a scoping analysis comparing variable renewable energy (VRE) sources with SMRs for repowering CPPs in the Korean context. The analysis indicates that SMRs may be a more favorable option than VRE sources, particularly due to their load-following capabilities. In this study, two types of SMRs were investigated: high-temperature gas reactors (HTGRs) and pressurized water reactors (PWRs). HTGRs are suitable to fit the high-temperature operating conditions of steam turbines but require multiple units due to their low volumetric flow rates. PWRs, while matching the volumetric flow rate of existing CPP turbines, require additional thermal energy sources to meet the high-temperature operating conditions of steam turbines. Lastly, an analysis of necessary regulatory and legislative changes in South Korea’s nuclear framework is presented, identifying several key regulatory issues for repowering coal with nuclear energy.

From Microalgae to Biofuels: Investigating Valorization Pathways Towards Biorefinery Integration

The rapid growth of the world population led to an exponential growth in industrial activity all around the world. Consequently, CO2 emissions have risen almost 400% since 1950 due to human activities. In this context, microalgae biomass has emerged as a renewable and sustainable feedstock for producing third-generation biofuels. This study explores the laboratory-scale production of bioethanol and biomethane from dried algal biomass. The first step was to evaluate and optimize the production of glucose from the biomass. Thus, three different techniques with three different solvents were tested to identify the most effective and efficient in terms of saccharification yield. With the assistance of an autoclave or a high-temperature water bath and 0.2 M NaOH as a solvent, yields of 79.16 ± 3.03% and 85.73 ± 3.23% were achieved which correspond to 9.24 and 9.80 g/L of glucose, respectively. Furthermore, the most efficient method from the pretreatment step was chosen to carry out a factorial design to produce bioethanol. The experiments showed that the loading of cellulase was of crucial importance to the optimization of the process. Optimized ethanolic fermentation yielded ethanol concentrations up to 4.40 ± 0.28 g/L (76.12 ± 4.90%) (0.3 Μ NaOH, 750 μL/gcellulose and 65 μL/gstarch), demonstrating the critical role of cellulase loading. Biomethane potential (BMP) assays on fermentation residues showed increased yields compared to untreated feedstock, with a maximum methane yield of 217.88 ± 10.40 mL/gVS. Combined energy production from bioethanol and biomethane was calculated at up to 1044.48 kWh/tn of algae feedstock, with biomethane contributing 75.26% to the total output. These findings highlight the potential of integrated algae-based biorefineries to provide scalable and sustainable biofuel solutions, aligning with circular economy principles.

Rapid Visual Detection of Red Sea Bream Iridovirus Using a Novel Cross-Priming Amplification-Based Lateral Flow Assay.

Red sea bream iridovirus (RSIV) occurs mainly at high water temperatures and infects more than 30 different species of fish. In Asia, infected fish cause mass mortality every year. Molecular diagnostics is a technology that efficiently detects and identifies a wide range of fish pathogens through rapid and sensitive analysis of their genetic material. Rapid viral detection is essential for effective disease control. In this study, we developed and validated a cross-priming amplification-based lateral flow assay (CPA-LFA) suitable for field diagnosis owing to its short diagnostic time and simple diagnostic process. The CPA-LFA achieved optimal performance with concentrations of 4 mM MgSO4, 1.2 mM dNTPs and 0.7 M betaine, with the reaction conducted at 60°C for 60 min. The developed CPA-LFA could specifically identify RSIV without cross-reactivity with several pathogens commonly reported in various fish cell lines and fish. The 95% limit of detection (LOD95%) of CPA-LFA was 385.76 copies/μL, which was comparable to that of conventional polymerase chain reaction (PCR). Quantitative PCR (qPCR) was used to identify true-positive and true-negative samples from 210 fish samples (160 from cultured fish and 50 from artificially infected fish). Compared with qPCR, CPA-LFA classified six positive samples as false positives. The viral load of these samples was determined to be less than 195.1 copies/μL. The diagnostic sensitivity and specificity of CPA-LFA were 94.34% and 100%, respectively. Furthermore, inter-operator reproducibility testing yielded a kappa value of 1.0, indicating perfect agreement. Therefore, the novel CPA-LFA is especially well-suited for field diagnostics owing to its straightforward diagnostic procedure and capability to quickly and accurately detect RSIV.

Summer Ostreopsis blooms in San Sebastian (South-East Bay of Biscay): The importance of substrate features.

During summer 2020 and 2021, harmful episodes of Ostreopsis were first reported in the Bay of Biscay, affecting the Spanish Basque coast, specifically the city of San Sebastian. This led to implement samplings during summer 2022 and 2023 within this region; two close sites distinguished, primarily, by their substrate features were selected. The abundances of Ostreopsis spp. were significantly higher at Ondarreta beach compared to La Concha beach, with the former seemingly favoured by its high water temperature, relatively lower hydrodynamics and great macroalgal coverage of its rocky substrate, observing maximum abundances of 1.86×106 cells/g and 1.33×105 cells/L in the epiphytic and planktonic samples, respectively. Finally, molecular analyses demonstrated the co-occurrence of Ostreopsis sp. 9 (Ostreopsis cf. siamensis) and Ostreopsis cf. ovata at La Concha Bay, confirming for the first time the presence of the latter on the Spanish coast of the Bay of Biscay.

An Interpretation Method of Gas–Water Two-Phase Production Profile in High-Temperature and High-Pressure Vertical Wells Based on Drift-Flux Model

With the increasing demand for oil and gas, the depth of some vertical gas wells can reach 6000 m. At this time, the downhole fluid is in a state of high temperature and pressure, and interpretation of the production logging output profile faces the problem of inaccurate production calculations and difficulty judging the water-producing layer. The drift-flux model is usually used to calculate the gas–water two-phase flow. The drift-flux model is widely used to describe the two-phase flow in pipelines and wells because of its accuracy and simplicity. The constitutive correlations used in drift-flux models, which specify the relative motion between phases, have been extensively studied. However, most of the correlations are only extended by laboratory data of small pipe diameters at standard temperature and pressure and do not apply to high-temperature and high-pressure large-diameter gas wells. Therefore, we improved the distribution coefficient and drift velocity of drift-flux correlations in this study for high-temperature and high-pressure gas wells with large pipe diameters. Therefore, this study improved the distribution coefficient and drift velocity of the drift-flux correlations for high-temperature and high-pressure gas wells with large pipe diameters. In practical application, the coincidence rates of gas production and water production calculated by the new drift-flux model were 12.68% and 19.39%, respectively. For high-temperature and high-pressure deep wells, the measurement errors of production logging instruments are significant, and surface laboratory pipelines are challenging to configure and equip with actual high-temperature and high-pressure conditions. Therefore, this study used the method of numerical simulation to study the flow characteristics of the two phases of high-temperature and high-pressure gas and water to provide a basis for identifying the water layer. Combined with the proposed drift-flux correlations and the new method of determining the water-producing layer, a new method of production profile interpretation of high-temperature and high-pressure gas wells is obtained.

Phytoplankton community composition links to environmental drivers across a fjord to shelf gradient on the central coast of British Columbia

Rapid environmental change is altering coastal phytoplankton dynamics and, thereby the productivity of coastal marine food webs. Unfortunately, a paucity of phytoplankton community data hinders the prediction of future conditions in ecologically productive regions such as the coastal northeast Pacific. To help fill this gap, this study characterized phytoplankton communities from 2018 to 2020 across a fjord, channel and shelf station transect on the central coast of British Columbia, Canada. Monthly samples were collected for microscopy-based taxonomy and pigment-based phytoplankton composition (i.e. CHEMTAX and size-fractionated chlorophyll). Correlation analysis was used to investigate drivers of phytoplankton biomass and hierarchical clustering and redundancy analysis highlighted drivers of compositional trends. Spring blooms formed the peak of annual biomass at each station and earlier blooms at the fjord station suggested a sheltering effect from winter wind conditions. Later spring blooms at the channel station coincided with seasonal wind reductions and increased sunlight. Of the six derived compositional clusters, three represented flagellate dominated conditions at all stations: two represented low biomass winter conditions and the third, moderate biomass spring and autumn blooms occurring under nutrient replete conditions. The remaining three clusters were diatom-dominated and spanned much of the growing season. The first diatom cluster represented Skeletonema marinoi dominated samples, many from 2020, observed under moderate nutrient and high stratification and freshwater discharge conditions. The second represented high diatom richness spring bloom conditions at all stations that were associated with nutrient depletion. Finally, the third included 2018 and 2019 summer shelf samples showing harmful Rhizosolenia setigera and Pseudo-nitzschia seriata blooms under high surface water salinity and temperature. These results highlight high spatial-temporal variability and sensitivity of coastal northeast Pacific phytoplankton communities to altered freshwater, temperature and wind dynamics with potential for profound ecosystem level implications.

Efficacy of laundry practices in eliminating monkeypox virus (MPXV) from fabrics.

The declaration of mpox as a Public Health Emergency of International Concern highlights the need for interventions to interrupt virus transmission, including transmission via fabrics. Current World Health Organization guidance on clothes washing is based on a general consensus of virus inactivation; however, there is uncertainty about the efficacy of laundry detergents and disinfectants or the reduction of risk achieved by washing clothes for monkeypox virus (MPXV) specifically. This study investigates the efficacy of manual washing for inactivating MPXV from clothes. Using a simulated washing method, we evaluated the efficacy of commonly-used laundry products and high temperature water for inactivating MPXV on fabrics. Cotton and polyester fabrics were inoculated with MPXV for 1 min, placed in a microcentrifuge tube containing water or water with test product for 20 minutes, with agitation every 5 min to simulate manual washing. Sodium hypochlorite, liquid sanitizer, and two powdered laundry detergents dissolved in room temperature water, as well as 70-degree water alone, completely inactivated MPXV (>3 log10reduction or >99.9% inactivation) on both cotton and polyester fabrics. Given the expected concentrations of MPXV on fabrics, the low transfer rate of viruses from porous surfaces to skin, the effective inactivation of laundry processes, and the expected doses required for infection, we expect the risk of transmission after laundering contaminated fabrics to be low. This study provides evidence to support WHO guidance for MPXV inactivation, reducing the viral load on fabrics to prevent the spread of mpox in both healthcare and household settings.

Printed cellular structure enhancing re-passivation of stress corrosion cracking in high-temperature water

Printed cellular structure enhancing re-passivation of stress corrosion cracking in high-temperature water

Comparative experimental investigation on shale fracture propagation induced by high-temperature water and carbon dioxide

Comparative experimental investigation on shale fracture propagation induced by high-temperature water and carbon dioxide

Thermal management performance analysis and improvement for a commercial vehicle engine compartment through a 1D/3D co-simulation method

The thermal management performance of a commercial vehicle engine compartment is crucial for improving overall vehicle performance and promoting green transportation. In this study, a one-dimensional (1D) and three dimensional (3D) CFD co-simulation method has been proposed for the modeling and simulation of thermal management of a commercial vehicle engine compartment. The steady-state temperature and velocity vector distribution in engine compartment has been obtained through 3D CFD approach. With data exchange between the cooling circuit and air conditioning circuit, the mathematical characterizations of the thermal management performance have been further investigated through 1D simulation and validated using test results. The comparison show that the obtained results for thermal management performance are consistent with test results, validating the accuracy of the co-simulation model. The results indicate an obvious thermal backflow phenomenon in the upper area of the intercooler module, causing a high outlet water temperature of the engine cooler. Thus, a deflector structure for eliminating the thermal backflow problem has been presented, and the heat dissipation effect has been analyzed. The co-simulation results show an improvement in cooling performance that the ATO value of cooling circuit decreased by 2.5% and intercooler constant of air conditioning circuit decreased by 12.1%. The proposed 1D/3D co-simulation method provides a reliable reference for developing the thermal management system of commercial vehicle engine compartment.

Synthesis & Characterization of Parylene D films on Nafion-117 for Robotic Arm

The era of industrialization needs the discovery of new materials rapidly. The ionic nature of Nafion 117 makes it feasible for the biosensors and other robotic devices. The uncoated nafion 117 is highly unstable at high temperature and evaporative water loss is also present. The coating of noble material make it more efficient and highly stable at adverse conditions. The high cost of noble material may be barrier fpr its day to day applications. Therefore, parylene D has been selected as coating material for base substrate material to maintain its efficiency as well as working. The present study is done to compare the parylene D coated material with the uncoated nafion 117. The water holding capacity and ion exchange capacity has been investigated in the given research.

Dynamic changes in wettability within a nanoscale slit of coal during hot flue gas injection

Aiming at exploring the dynamic changes in wettability within a nanoscale slit of coal during hot flue gas injection, a competitive wetting model of coal–water–multicomponent gas that considers real gas occurrence pressures was established in this study. Additionally, various methods that influence the wettability within the slit at different hot flue gas injection pressures were investigated, and the mechanism of wettability changes within the slit was elucidated based on the analyses on interaction energy, radial distribution function curve, molecular migration characteristics at the slit outlet, density distribution, and contact angle. The research findings are as follows. The intensities of the interaction energy between high-temperature and low-temperature water molecules differ markedly after the completion of hot flue gas injection at different pressures. Both the radial distribution function and the interaction energy indicate that the two types of water molecules fuse the most thoroughly at 20 MPa. At low pressures, the number of water molecules in the observation area changes slightly. The high-yielding period of the two types of water molecules at 20 MPa is 1.5 ns longer than that at 25 MPa, and the numbers of the two types of water molecules are less different at the same time at 20 MPa except for the case at 3 ns. After the injection, the densities of the preexisting water molecules and CO2 and the contact angle of the hot flue gas bubble demonstrate that the wettability transition within the slit is more complete at relatively high pressures (20 and 25 MPa) from two perspectives. At 20 MPa, the “re-absorption” is milder, and the bubble is milder and forms a smaller contact angle on the coal substrate. Based on the above research findings, it is concluded that raising the injection pressure of hot flue gas is conducive to the transition from water wetting to gas wetting and the elimination of the water lock effect. This research provides support for selecting the optimal hot flue gas injection pressure at the molecular level.

Seasonal distribution of fishes at nearshore meadows predominated by <i>Zostera marina</i> and <i>Ulva fenestrata</i> in the Stark strait (Peter the Great Gulf, Sea of Japan)

The fish species diversity, fish density, and distribution in the nearshore beds of Zostera marina and Ulva fenestrata have been assessed by SCUBA visual counts in May–September and November 2021. In total, 23 fish species have been registered. The fish species richness increases from 8–13 species in May to a maximum of 17–19 species at the end of June. Then it slightly decreases in July–September and reaches its lowest values in November (2–5 species). The same changes have been noted for the fish density. Fish diversity in the Zostera beds is higher than in the Ulva ones. The similarity of the fish species composition between Zostera and Ulva is low (the Sørensen-Czekanowski index varied from 0.32 to 0.44). In general, fish density is low (from 2.4 to 112.4 ind./50 m2 in Ulva (in November) and Zostera (in July) beds, respectively), although with an exception for Opisthocentrus spp. and Gymnogobius heptacanthus juveniles. An abnormal high bottom water temperature (above 26°C) in late July–early August has led to temporal avoidance of shallow water with plant beds by fishes (except for Gymnogobius heptacanthus) and their migration to a depth of 3.5–4.5 m, where the temperature was lower by 4.0–5.7°С.