Oxide Content Research Articles

COMPLICATED THERMAL HISTORY OF THE LITHOSPHERIC MANTLE OF THE ANABAR REGION: RECONSTRUCTIONS BASED ON XENOCRYSTS FROM KIMBERLITES

The thermal history and thickness of the lithospheric mantlebeneath the kimberlite fields of the Eastern Anabar shield and adjacent territories of the Siberian craton were reconstructed based on the composition of clinopyroxene xenocrysts from the concentrate of kimberlite heavy fraction and mantle xenoliths. Garnet and spinel peridotites are most abundant in the lithospheric mantle beneath the five studied fields of the Siberian craton. Almost in all fields, the Mg# index of clinopyroxene decreases through depth. In the oldest Chomurdakh kimberlite field, both TiO2 and FeO contents vary slightly. The titanium oxide values markedly vary from 0 to 0.6 wt. % in the Triassic fields. The high titanium oxide contents in minerals are indicative of deep­seated metasomatic transformations of lithospheric mantle blocks in the northern Yakutia kimberlite province. The geotherm was fitted to the PT data set in the Gtherm program with the model involved D. Hasterok and D. Champan. The thermal lithosphere beneath the studied fields retained the thermal thickness up to 260 km. In the period between 430 and 230 Ma, it underwent a significant metasomatic transformation resulting in the formation of high­Fe and high­Ti blocks. It appears, that the thermal thickness declined to 190–200 km only in the north of the Siberian craton during the Jurassic period. This assumption is verified by the values of lithosphere thickness beneath the northern Kuoika field.

Nanotechnology strategy for inhibition of PARP1 and IL-17A-associated with neurotoxicity in rats exposed to hospital wastewater.

Hospital wastewater (HWW) poses a serious hazard to human health security concerning its high susceptibility to neurodegeneration. Water sources and ecosystems are exposed to a complicated pollution load from a variety of refractory organics and pharmaceutical active composites. This study evaluates the treated newly developed nanocomposite (NiFe2O4) HWW on the neural injury induced by HWW action in rats. Three groups of male Wistar rats were distributed, with eight rats in each: group I: tap water served as a control; group II: HWW; and group III: nano-HWW. Each group was intragastrical administrated with each type of water (2.5 ml/100 g b.wt/6 h) for 28 consecutive days. The open field test and Morris Water Maze assessed behavioral activity and spatial learning 2 days before the last day. The research demonstrated that HWW treated with nanocomposite (NiFe2O4) may exert decreased risks of the neural impairment effect of HWW. This improvement was achieved by reducing the neurotoxicity by lowering nitric oxide contents, lipid peroxidation, acetylcholinesterase, interleukin-17A (IL-17A), and poly(ADP-ribose) polymerase1(PARP1) while restoring the antioxidant biomarkers and neurotransmitter levels (β-endorphin, norepinephrine, dopamine, and serotonin) of the treated groups in the cortex and brainstem and enhancement of the histopathology of the cortex as well. In conclusion, this study introduced a newly developed nanotechnology application for treating HWW to protect from neural injury. The findings of this research have significant value for policymakers, Ministry of Health management, and environmental organizations in their selection of suitable techniques and procedures to optimize hospital wastewater treatment efficiency.

The influence of CeO2 on the oxidation resistance of TaC/Ni composites

The in-situ TaC/Ni composites with different CeO2 content (0 wt%, 1 wt%, 2 wt%) were prepared by reactive sintering method, and their oxidation behavior in air at 1073 K was analyzed by static cyclic oxidation method to investigate the influence mechanism of CeO2 on the oxidation resistance of composites. The results show that the CeO2 particles are distributed around the TaC particles in the Ni matrix, and the oxidation behavior of composites with different CeO2 content conforms to the linear kinetic law. The oxide film is mainly composed of NiTa2O6 and a small amount of NiO. The generation reactions of Ta2O5 and NiTa2O6 induce a high expansion and compressive stress in oxide scale, leading to the formation of nonprotective oxide film with pores and cracks on the surface. As the addition of CeO2 increases from 0 wt% to 2 wt%, the thickness of oxide scale on composites obviously reduces from 505 μm to 122 μm, and the Ni and Ta oxides content decreases, leading to the reduction of pores and cracks in oxide scale. The Ce ion generated from the dissolution of CeO2 particles mainly distributes in the Ta oxides during the oxidation process, which hinders the outward diffusion of Ni and Ta ions, resulted in the improved oxidation resistance of TaC/Ni composites.

Melatonin Mediates Cardiac Tissue Damage under Septic Conditions Induced by Lipopolysaccharide.

Lipopolysaccharide (LPS) is known to induce oxidative stress and inflammation, leading to significant damage in cardiac tissues. This study investigates the protective effects of melatonin (MLT) against LPS-induced oxidative damage, inflammation, and apoptosis in rat heart tissue. Rats were divided into four groups (n = 6 per group): control, melatonin-treated, LPS-treated, and LPS + melatonin-treated. Oxidative stress markers, including thiobarbituric acid-reactive substances (TBARSs) and advanced oxidation protein products (AOPPs), were measured. Additionally, inflammatory markers, such as interleukin-6 (IL-6) levels, inducible nitric oxide synthase (iNOS) and nitric oxide (NO) content, and apoptotic markers, caspase-3, caspase-9, and acidic DNase activity, were evaluated. LPS treatment significantly increased TBARS, AOPP, and IL-6 levels, as well as the activity of caspase-3, acidic DNase and iNOS and NO content compared to the control group. Co-treatment with melatonin significantly reduced the levels of TBARS and AOPP levels, and caspase-3 and acidic DNase activities nearly matched those of the control group, while caspse-9 was still slightly increased. Interestingly, IL-6, iNOS and NO levels were significantly decreased but did not fully match the values in the control group. Melatonin mitigates LPS-induced oxidative stress, inflammation, and apoptosis in rat heart tissue by affecting all studied parameters, demonstrating its potential as a therapeutic agent for conditions characterized by oxidative stress and inflammation. Further research is warranted to explore the clinical applications of melatonin in cardiovascular diseases.

Comparison of Microleakage of Monolithic Zirconia after Surface Treatment and Thermal Cycles Using Data Analysis Software

Objective: The aim of this study was to investigate the microleakage of monolithic zirconia after different surface treatments using computer software. Materials and Methods: Three different monolithic zirconia ML (Multilayered), STML (Super Translucent Multilayered), UTML (Ultra Translucent Multilayered) were prepared as discs with a diameter of 15 mm and a thickness of 1.2 mm. Four different surface treatments (Hydrofluoric acid, Tribochemical silica coating, Hydrofluoric acid application + Tribochemical silica coating, Milling + Tribochemical silica coating + Hydrofluoric acid application) were applied to the prepared samples according to their groups (n=8). Samples, Group C: Control group, Group HF: Hydrofluoric acid application, Group T: Tribochemical silica coating, Group HF+T: Hydrofluoric acid application + Tribochemical silica coating, Group F+HF+T: Milling + Tribochemical silica coating + Hydrofluoric acid application, then adhesive system was applied to all specimens and repaired with resin cement. The specimens were thermocycled for one year aging and then immersed in basic fuchsin solution to evaluate microleakage. The specimens were separated with a micro-cut device and evaluated under a stereomicroscope. The dimensions of the images were measured in Python program and the permeability and surface treatments of the zirconia samples were compared. Statistical analysis was performed by two-way ANOVA (p<0.05). Results: UTML F+HF+T showed the lowest microleakage (12.15 ± 1.69), while ML C showed the highest microleakage (73.93 ± 1.59). Among the zirconia specimens, the highest adaptation was obtained in the UTML zirconia (37.59 ± 23.58). Conclusion: According to the data obtained, milling + tribochemical silica coating + acid application surface treatments are recommended for the repair of monolithic zirconia restorations. The sintering temperature and Yttrium Oxide (Y2O3) content of the monolithic zirconia used are effective factors in microleakage after repair.

New Eco-Cements Made with Marabou Weed Biomass Ash

Biomass ash is currently attracting the attention of science and industry as an inexhaustible eco-friendly alternative to pozzolans traditionally used in commercial cement manufacture (fly ash, silica fume, natural/calcined pozzolan). This paper explores a new line of research into Marabou weed ash (MA), an alternative to better-known conventional agro-industry waste materials (rice husk, bagasse cane, bamboo, forest waste, etc.) produced in Cuba from an invasive plant harvested as biomass for bioenergy production. The study entailed full characterization of MA using a variety of instrumental techniques, analysis of pozzolanic reactivity in the pozzolan/lime system, and, finally its influence on the physical and mechanical properties of binary pastes and mortars containing 10% and 20% MA replacement content. The results indicate that MA has a very low acid oxide content and a high loss on ignition (30%) and K2O content (6.9%), which produces medium–low pozzolanic activity. Despite an observed increase in the blended mortars’ total and capillary water absorption capacity and electrical resistivity and a loss in mechanical strength approximately equivalent to the replacement percentage, the 10% and 20% MA blended cements meet the regulatory chemical, physical, and mechanical requirements specified. Marabou weed ash is therefore a viable future supplementary cementitious material.

Grain Structure Engineering in Screen-Printed Silver Flake-Based Inks for High-Temperature Printed Electronics Applications.

We extensively studied serigraphic screen-printed commercial silver flake inks loaded with silicon inclusions in order to achieve pinning at the grain boundaries. Based on grain size measurements using electron backscattered diffraction (EBSD), commercial silver ink with silicon microparticle content of 5 wt.% shows significant grain growth retardation compared to pristine silver ink, which stabilizes electrical conductivity up to 700 °C via a Zener pinning mechanism. The modified silicon-loaded silver ink experiences a two-times increase in grain size when heated up to 700 °C, compared to a seven-times increase for pristine silver ink. In turn, this enables operation temperatures significantly higher than the conventional operational window of microparticle-based silver inks, which are usually limited to 400 °C. Using isothermal exposures of 10 min up to 4 h, this phenomenon is observed at temperatures ranging from 250 °C to 900 °C. The electrical conductivity stability, grain size evolution and oxide contents were studied up to 4 h. The activation energy of silver ink with silicon inclusions is 54% lower than for pristine silver ink due to the pining effect, which retards grain growth via the Zener mechanism. Most importantly, the electrical resistivity remains stable up to 700 °C, which is more than twice the operation limit for off-the-shelf screen-printable silver flake inks. Hence, we demonstrate that adding controlled amounts of silicon particles to silver inks for grain structure engineering can open new vistas of possibilities for screen-printed metallic inks.

Study on the effect of TiC/B on the performance of laser cladding in-situ fabricating wear-resistant self-lubricating coatings

To improve the wear resistance of IN718, coatings containing the self-lubricating phase h-BN were prepared and the coating properties were analyzed in relation to the variation of laser power. The results show the TiC added to the cladding powder partially decomposes and in-situ fabricates new reinforcing phases TiN, B4C, etc. The lubricating phase h-BN was in-situ fabricated by adding B into the powder. As the laser power increased from 1.6 kW to 2 kW and 2.5 kW, eutectic microstructures of high melting point reinforcing and lubricating phases were observed. Due to the decomposition of TiC and in-situ fabricated of TiC2, TiN and B4C concentrations changing with the laser power, the surface hardness of the coatings prepared at 2.5 kW was the highest at 391.03HV0.5. Which is 1.096 and 1.108 times of 1.6 kW and 2 kW. At room temperature, the coating fabricated by 2 kW has the highest average friction coefficient of 0.537. This is because the self-lubricating phase h-BN is a high-temperature lubricating phase and the wear surface has a low oxide content, and is influenced by the hardness of the coating. At 500°C, the coating fabricated with 2.5 kW has the lowest average friction coefficient due to the best synergistic effect of the lubricating and reinforcing phases at 0.376. The 2.5 kW coating has the best wear resistance, with wear rates 0.69 and 0.54 times at room temperature and 0.82 and 0.8 times at 500°C of 1.6 kW and 2 kW. The wear mechanism at room temperature is abrasive wear, and at 500°C is mainly a combination of h-BN and oxide synergistic lubrication.

Reinforcement effects of graphene oxide in polyamide 6 nanocomposite system synthesized by in-situ polymerization

In this study, the excellent enhancement in the mechanical properties and thermal properties of polyamide 6 (PA6) by the incorporation of very low content of graphene oxide (GO) was achieved. For example, the Young's modulus of PA6/GO nanocomposites with 0.5 wt% GO was 138 % higher than that of PA6. In addition, the thermal decomposition temperature increased from 341 °C of PA6 to 361 °C by the addition of only 0.5 wt% of GO. The detailed effect of GO on the structure (e.g. dispersibility, orientation, alignment, crystallinity, interfacial interactions) of the nanocomposites were investigated. Understanding the reinforcing effect of GO and its mechanism is important for the designing of polymer nanocomposites which can provide strong candidates for light weight and smart applications in various fields.

A novel integrated soft sensing model for online cement clinker quality monitoring based on fuzzy fine-grained classification

The content of free calcium oxide (f-CaO) in cement clinker is an important index for cement quality. For the problems of multiple working conditions and unbalanced distribution of sample labels in cement clinker production, a soft sensing method of cement clinker f-CaO content based on fuzzy fine-grained classification (FF) is proposed. First, a divide-and-conquer strategy is used to divide the samples into high, medium, and low subsets according to cement clinker f-CaO and extract the fine-grained features under diverse types of multiple production conditions. Second, fuzzy classification based on the membership function is used in the FF model to solve the uncertainty of the sample categories. To ensure the rationality of the classification, the fuzzy membership rule is combined with a convolutional neural network to implement the fuzzy classification method. Finally, different feature extraction methods are proposed to be selected according to the data size of various categories of samples. After experimental validation, the evaluation metrics of RMSE decreased by 4.5 % and R2increased by 17.8 % for the direct classification model compared to the single model. The RMSE of the fuzzy classification model over the direct classification model was again reduced by 2.34 % and R2was again improved by 7.24 %, showing the effectiveness of the proposed soft measurement model.

Marine clay maturation induces systematic silicon isotope decrease in authigenic clays and pore fluids

Marine silicate alteration exerts a major influence on marine carbon and cation cycles, but has proven difficult to quantify. In this context, silicon isotopes of marine pore fluids became an important tracer. However, poorly constrained silicon isotope signatures of precipitates produced during silicate alteration (i.e. authigenic clays) remain a major source of uncertainty. Here we present in situ silicon isotope analyses of marine authigenic clays (intergrown iron-smectites and iron-glauconites) occurring within recent sediments from the Oregon margin, eastern North Pacific. We identify a trend to lower silicon isotopes (from −2.24‰ to −3.17‰), accompanied by decreasing aluminum/silicon ratios and increasing potassium oxide contents, which we interpret as an isotopic shift caused by progressive clay maturation via dissolution-reprecipitation reactions. Our modelling suggests that this clay maturation pathway, together with mixing of other fluid sources, may induce pore fluid silicon isotope shifts of up to −1.7‰, if sufficient newly precipitated clays are re-dissolved. This could potentially produce silicon isotopes values significantly lower than seawater and implies that conventional isotope-based approaches underestimate the prevalence of marine silicate alteration. Our findings highlight that clay maturation must be considered when interpreting silicon isotope signatures in terms of marine silicate alteration and upscaling to global element cycles.

Mechanical processing of wet stored fly ash for use as a cement component in concrete

Wet storage effects on fly ash mean that processing may be necessary to achieve the physical properties required for use in concrete. This paper considers drying, de-agglomeration and milling of various wet stored fly ashes at laboratory and pilot/benchtop scales, towards meeting these. In the laboratory, different batch quantities and milling times with as-received/pre-screened materials were examined using a ball mill. Greater particle size reductions were obtained with increased milling time but at gradually reducing rates. Pre-screening and batch quantity had relatively minor effects on particle size reductions, with small differences also found between wet and dry stored fly ash. Extended milling time resulted in a darkening of colour; slight increases in loss-on-ignition, the main oxides content and crystalline components; reductions in water requirement (to a point); and greater reactivity. Similar effects were generally noted in concrete for the superplasticising admixture dose to achieve a target slump and compressive (cube) strength. At pilot/benchtop scale, a dryer-pulveriser and spiral jet mill were used, which gave general agreement with the behaviour noted in the laboratory, but with the effects tending to be less. Fineness levels in Standards were achievable, with subsequent performance in concrete, appearing to depend on the milling process used.

The Effect of Spray Distance on the Hot Corrosion Behavior of HVOF‐Sprayed NiCrAlY Coatings in a Simulated Gas Turbine Environment

ABSTRACTTo utilize the unique properties of coatings produced using the high‐velocity oxy‐fuel (HVOF) method, this study examined the effect of spray distance on the hot corrosion behavior of NiCrAlY coatings deposited on a steel substrate. The coating samples were obtained at spray distances of 20, 25, and 30 cm. The flow rates of oxygen and propane were maintained constant at 300 and 60 lit/min, respectively. Additionally, the powder feeding rate was 32 g/min. The samples were then subjected to the hot corrosion test in a salt mixture of Na2SO4−60% V2O5 at 900°C in an ambient atmosphere. The surface and the cross section of the samples were observed using a scanning electron microscope (SEM) and the chemical composition of different sections was determined by energy‐dispersive spectroscopy (EDS). The phases were also characterized using X‐ray diffraction analysis (XRD). The best corrosion resistance was found in the sample coating formed at a spraying distance of 20 cm, as the results showed that increasing the spraying distance led to a reduction in the thermal and kinetic energy of the flame, resulting in increased porosity in the coating. This behavior can be attributed to the low oxide content of the coating, the higher aluminum content, and the richer NiAl phase, which serves as a reservoir for aluminum.

Effect of Sm2O3 on thermal, optical, mechanical, gamma and neutron shielding properties of zinc-boro-vanadate glasses

Abstract The effect of Sm2O3 on thermal, optical, mechanical, gamma and neutron shielding properties of newly prepared zinc borovanadate glasses has been investigated. Density is found increased and molar volume decreased with Sm2O3 content. The glass transition temperature ( T g ) , crystallization temperature ( T c ) and the peak crystallization temperature ( T P ) increased with increase of rare earth oxide content. These findings demonstrated an excellent glass-forming ability and thermal stability of the glasses. The optical properties have been explored through UV–vis spectroscopy. The indirect optical band gap energy ( E opt ) decreased from 2.978 to 2.679 eV, Urbach energy ( ∆ E ) increased from 0.273 to 0.299 eV and refractive index increased from 2.403 to 2.489 with increase in Sm2O3. Elastic moduli, Poisson’s ratio, Hardness and fractal bond connectivity were computed theoretically as per Makishima Mackenzie model. It is found that these glasses have appreciable mechanical strength and rigidity. Phy-X/PSD software has been used to determine different radiation shielding characteristics for the energy range 0.015–15 MeV. The mass and linear attenuation coefficients are found higher, and half value layer, tenth value layer and mean free paths are found lower than many radiation shielding glasses quoted in the literature values. The obtained Z eq values varied from 15.828–29.118 for energy range from 0.015 to 15 MeV, which are greater than those reported for several commercial glasses, concretes and rocks. Due to the Compton scattering process, exposure build up and energy absorption factor are found to be highest in the medium energy region. The fast neutron removal cross-sections of the glasses are observed to be significantly high. For the first time, thermally stable and mechanically strong zinc borovanadate glasses mixed with Sm2O3 have been thoroughly investigated for various properties and concluded that these glasses are suitable for optoelectronics and γ-shielding applications.

Pre-treated municipal solid waste bottom ash as alkali-activated mortar precursor

Pre-treated incinerator bottom ash was used as a precursor of alkali-activated mortars. Control mortars were produced using coal fly ash. Different combinations of alkaline activator were tested (sodium oxide/binder ratio (4%, 6%, 8%, 10% and 15%) and silicon dioxide/sodium oxide ratio (0, 0.5, 1.0, 1.5 and 2.0)) and the influence of these on the mortar's mechanical performance was evaluated. The mortars were tested in both fresh (for density and workability) and hardened states (for dry density, compressive and flexural strengths and modulus of elasticity) after 7, 28, 91 and 182 days. The first stage of work was precursor pre-treatment in a sodium hydroxide solution to prevent the expansion of fresh specimens due to the reaction of aluminium with the alkaline activator. The pre-treatment was effective in preventing excessive hydrogen gas generation during setting, leading to dimensional stability and improved strength. Different optimum sodium oxide contents were observed after 28 days (i.e. 15% for fly ash specimens and 8% for bottom ash specimens). The results of a simplified life-cycle assessment showed that such mixes exhibited lower overall carbon dioxide emissions when compared with cement-based counterparts. However, this trend was reversed with increasing contents of sodium hydroxide and sodium silicate.

FEATURES AND EXPERIENCE OF CONVERTING GAS-OIL BOILERS OF INDUSTRIAL CHP PLANTS TO BURNING BIOMASS AND SUB-BITUMINOUS COAL

The paper examines the features of biomass as a fuel and substantiates that for agrobiomass waste with a high content of alkali metal oxides and slag properties of ash, it is more appropriate to burn it in a dense bed in the form of pellets, which ensures a temperature at the exit from the furnace of no more than 900 °C, a low part of fly ash and low content of unburned carbon in it, and so eliminates the risk of smoldering deposits with their melting and slagging. Technical solutions are given and the experience is presented of gas and oil boilers of CHP plants of sugar factories reconstruction with their transfer to the burning of biomass and/or coal in a dense bed on a direct-flow grate with the replacement of the air heater with air-water heater, with the addition of stages of the boiling economizer to compensate for the decrease in the heat perception of the furnace screens, maintaining the overall height of the boiler and the plane of the boiler cell. The reconstruction of boilers according to the developed technical solutions is possible to perform in the interval between production seasons, its implementation on boilers BKZ-75 GMA of Radekhiv and Chortkiv sugar factories allowed to achieve acceptable technical, economic and environmental indicators and ensured payback due to the difference in commercial prices of gas and of agrobiomass pellets. It is proposed to replicate the positive experience in the creation of decentralized regulating thermal generation capacities of the country. Bibl. 30, Fig. 3, Tab. 4.

Unveiling the influence of zirconium on the corrosion behavior of Fe-36Ni Invar alloy

The influence of zirconium (Zr) on the corrosion resistance of Fe-36Ni Invar alloy in a 3.5 wt% NaCl solution was systematically investigated. Results indicated that adding Zr promoted the formation of Zr-bearing intermetallic compounds (Ni7Zr2 and Ni2Zr). The phases suppressed the grain growth and numerous dislocations were enriched around the Ni-Zr phases. Unfortunately, the incorporation of Zr into Fe-36Ni Invar alloy impaired corrosion resistance. The marked disparity in Volta potential between the Ni-Zr phases and the matrix signified the existence of micro-galvanic coupling, which caused the matrix to dissolve preferentially. Furthermore, the matrix around the Ni-Zr phases possessed high dislocation density, promoting the emergence of local galvanic corrosion. The introduction of Zr also decreased the protectiveness of the passive film, which was ascribed to the reduction of the thickness of the passive film and the beneficial oxide content in the passive film.

Protective effects of dietary protein against nitrite stress in grass carp (Ctenopharyngodon idella): A new perspective

Protein constitutes the predominant essential nutrient in fish feed. Despite extensive research efforts on the dietary protein of fish, limited attention has focused on its potential antistress properties. Therefore, this study sought to examine the impact of dietary protein on the liver structure of grass carp (Ctenopharyngodon idella) and its underlying molecular mechanism after nitrite stress, with the objective of elucidating the role of dietary protein in the stress response of fish. Specifically, various levels of dietary protein (16 %, 19 %, 22 %, 25 %, 28 % and 31 %) were investigated for their effects on liver tissue damage, oxidative stress, endoplasmic reticulum (ER) stress, autophagy and apoptosis in grass carp after exposure to a nitrite solution at a concentration of 10 mg/L for a duration of 96 h.Our study revealed that exposure to nitrite solution resulted in liver structural damage in grass carp. However, 22–25 % dietary protein levels might attenuate the impact of nitrite stress by decreasing liver contents of nitric oxide (NO), peroxynitrite anion (ONOO-), reactive oxygen species (ROS), protein carbonyl (PC), and malondialdehyde (MDA), which is reflected in serum activities of glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT). Histological analysis further supported the protective role of appropriate protein levels (22–28 %) in alleviating nitrite-induced liver tissue damage. Subsequent investigations demonstrated that optimal dietary protein levels decreased ER stress and autophagy in fish by modulating the expression of gene and protein involved in 78 kDa glucose regulated protein (GRP78) pathway and autophagosome formation process, respectively. Meanwhile, appropriate dietary protein levels decreased the activities of caspase-3, caspase-8 and caspase-9 by inhibiting both death receptor pathway and mitochondrial pathway associated with apoptosis. Finally, based on regression analysis of liver ONOO− content, the dietary protein requirement for grass carp (721–1381 g) under nitrite stress was determined to be 25.07 %. Overall, this study provides novel evidence that optimal protein levels can enhance the resistance of grass carp to nitrite stress and mitigate liver tissue damage by reducing oxidative stress cascade damage.

The S-nitrosylation of monodehydroascorbate reductase positively regulated the low temperature tolerance of mini Chinese cabbage

One of the main environmental stresses that considerably reduced vegetable yields are low temperature stress. Brassinosteroids (BRs) is essential for controlling a number of physiological functions. Protein S-nitrosylation is thought to be a crucial process in plants that use NO to carry out their biological functions. The exact process by which the mini Chinese cabbage responded to low temperature stress through BR-mediated S-nitrosylation modification of the monodehydroascorbate reductase (MDHAR) is still unknown. BR significantly increased the S-nitrosoylation level and antioxidant capacity at low temperature. One noteworthy development was the in vitroS-nitrosylation of the MDHAR protein. The overexpressed lines exhibited considerably high nitric oxide (NO) and S-nitrosothiol (SNO) contents at low temperature compared to the WT lines. Treatment of the WT and OE-BrMDHAR lines with BR at low temperature increased the antioxidant capacity. According to the biotin signaling, BR considerably enhanced the silenced lines total S-nitrosylation level in vivo at low temperature. Furthermore, BrMDHAR, BrAAO, and BrAPX gene transcript levels were dramatically up-regulated by BR, which in turn reduced the H2O2 content in the silenced lines. These findings demonstrated that the S-nitrosylation of MDHAR was essential to the improvement of BR on low-temperature tolerance in the mini Chinese cabbage.

Enhanced thermal insulation and corrosion resistance in Ni-Fe cermet through incorporation of high-entropy spinel oxides

The influence of high-entropy spinel oxide (HESO) content on the microstructure, electrical conductivity, and high-temperature corrosion resistance of HESO/NiFe cermets were investigated. The results found that the addition of 10 to 30wt.% HESO enhanced sintering densification and thermal insulation, although it also resulted in reduced electrical conductivity. Isothermal oxidation tests conducted at 900 °C for 10hours revealed that cermets containing 30 to 50wt.% HESO exhibited significantly lower weight gains (0.954 to 1.167mgcm⁻²) and oxidation rate constants (0.1057 to 0.1525mg² cm⁻⁴ h⁻¹). Furthermore, static corrosion tests in AlF₃-KF-Al₂O₃ molten salt demonstrated that HESO effectively mitigated the erosion of the metallic phase by the fluoride molten salt. This study holds significant potential by providing new insights for the design of inert anodes for aluminum electrolysis and exploring the practical applications of high-entropy oxide materials.