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1.
Molecules ; 29(17)2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39274894

ABSTRACT

Accurately measuring water holdup in horizontal wells is crucial for effectively using heavy oil reservoirs. The capacitance method is among the most widely used and accurate techniques. However, the absence of suitable insulating materials at high temperatures and pressures limits the effectiveness of capacitive water holdup measurement in heavy oil thermal recovery. This study introduces a new composite material based on an aviation-grade, special glass glaze as the insulating medium doped with inorganic components (CaSO4, MgSO4, Ca(OH)2, and SiO2). This new composite material demonstrates outstanding insulating performance under high-temperature and high-pressure conditions in water. A water environment with a high temperature of 350 °C and a pressure of 12 MPa considerably enhances the composite material's insulation. After 72 h of continuous use, the insulation performance remains 0.3 MΩ. The layers exhibit improved insulation and stability, maintaining integrity through five consecutive temperature shocks in 500 °C air and 20 °C water. XRD, IR, SEM, and TEM analyses reveal that the new composite material is amorphous after firing and that the addition of inorganic components improves the bonding between the glass glaze components and contributes to a denser structure. Simultaneously, SEM and TEM analyses indicate that adding inorganic components results in a smoother, crack-free, and more compact surface of the special glass glaze. This enhancement is crucial for the material's long-term stability in high-temperature and high-pressure water environments.

2.
Molecules ; 29(17)2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39275054

ABSTRACT

The rheology control of water-based drilling fluids at ultra-high temperatures has been one of the major challenges in deep or ultra-deep resource exploration. In this paper, the effects of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonimide) (ILA), 1-ethyl-3-methylimidazolium tetrafluoroborate (ILB) and N-methyl, butylpyrrolidinium bis(trifluoromethanesulfonimide) (ILC) on the rheological properties and filtration loss of polymer-based slurries at ultra-high temperatures (200 °C and 240 °C) are investigated by the American Petroleum Institute (API) standards. The results show that ionic liquids with different structures could improve the high-temperature rheological properties of polymer-based drilling fluids. The rheological parameter value (YP/PV) of the polymer-based slurry formulated with ILC is slightly higher than that with ILA at the same concentration, while the YP/PV value of the polymer-based slurry with ILA is slightly higher than that with ILB, which is consistent with the TGA thermal stability of ILA, ILB, and ILC; the thermal stability of ILC with pyrrolidine cations is higher than that of ILA with imidazole cations, and the thermal stability of ILA with bis(trifluorosulfonyl)amide anions is higher than that of ILB with tetrafluoroborate anions. Cation interlayer exchange between organic cation and sodium montmorillonite can improve the rheological properties of water-based drilling fluids. And meantime, the S=O bond in bis(trifluorosulfonyl)amide ions and the hydroxyl group of sodium montmorillonite may form hydrogen bonds, which also may increase the rheological properties of water-based drilling fluids. ILA, ILB, and ILC cannot reduce the filtration loss of polymer-based drilling fluids at ultra-high temperatures.

3.
Sci Rep ; 14(1): 21653, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39289363

ABSTRACT

The oxidation resistance of Hf0.28B0.72 and Hf0.11Al0.20B0.69 thin films was investigated comparatively at 700 °C for up to 8 h. Single-phase solid solution thin films were co-sputtered from HfB2 and AlB2 compound targets. After oxidation at 700 °C for 8 h an oxide scale thickness of 31  ±  2 nm was formed on Hf0.11Al0.20B0.69 which corresponds to 14% of the scale thickness measured on Hf0.28B0.72. The improved oxidation resistance can be rationalized based on the chemical composition and the morphology of the formed oxide scales. On Hf0.28B0.72 the formation of a porous, O, Hf, and B-containing scale and the formation of crystalline HfO2 is observed. Whereas on Hf0.11Al0.20B0.69 a dense, primarily amorphous scale containing O, Al, B as well as approximately 3 at% of Hf forms, which reduces the oxidation kinetics significantly by passivation. Benchmarking Hf0.11Al0.20B0.69 with Ti-Al-based boride and nitride thin films with similar Al concentrations reveals superior oxidation behavior of the Hf-Al-based thin film. The incorporation of few at% of Hf in the oxide scale decelerates oxidation kinetics at 700 °C and leads to a reduction in oxide scale thickness of 21% and 47% compared to Ti0.12Al0.21B0.67 and Ti0.27Al0.21N0.52, respectively. Contrary to Ti-Al-based diborides, Hf0.11Al0.20B0.69 shows excellent oxidation behavior despite B-richness.

4.
Article in English | MEDLINE | ID: mdl-39298880

ABSTRACT

With the ongoing intensification of global warming, thermal stress poses significant challenges to tilapia aquaculture. However, the molecular mechanisms underlying the cardiac response of tilapia to high temperatures remain largely unexplored. To address this knowledge gap, we investigated the effects of high-temperature stress on the transcriptomic landscape of the tilapia heart. RNA sequencing was performed on the hearts of Oreochromis aureus (AR), Oreochromis niloticus (NL), and hybrids (O. niloticus ♀ × O. aureus ♂, AN) under treatments of 28 °C, 36 °C, and 39 °C. Using a multi-method approach, including Differentially Expressed Genes analysis, Weighted Gene Co-expression Network Analysis, Fuzzy C-Means, Self-Organizing Map, and Support Vector Machine-Recursive Feature Elimination, we identified six marker genes at 39 °C (AR: ptges3, tuba1a; NL: ran, tcima; AN: slc16a1, fam184b). These genes exhibited strong positive correlations and increased expression under high-temperature conditions. Gene Set Enrichment Analysis and GENIE3 revealed that these marker genes closely regulate three cardiovascular-related pathways: adrenergic signaling in cardiomyocytes, vascular smooth muscle contraction, and cardiac muscle contraction. We hypothesize that the synergistic inhibition of these pathways by marker genes leads to the deterioration of cardiovascular function. In summary, thermal stress activates marker genes, which in turn inhibit cardiovascular pathways, impairing cardiac performance. We propose that these marker genes could serve as dynamic thermal indicators of cardiac performance in tilapia. Additionally, our findings provide theoretical support for improving the management of tilapia farming under high-temperature stress.

5.
Sci Total Environ ; : 176377, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39299320

ABSTRACT

In dryland farming, plastic film mulching can significantly increase crop yields, but the resulting residues impair soil health. Heretofore, only few studies had examined how heat treatment facilitates the rapid degradation of polyethylene (PE) residual films. Herein, we characterized the variations in micro-morphology, functional groups, and crystallinity of PE residual films after moderate heat exposure using a self-made flame-spraying equipment. The results revealed that solid residues (SR) obtained from flame-spraying showed a gravimetric weight loss of 9.39 %-15.35 % compared with untreated PE residual films (UPF). Scanning electron microscope equipped with energy dispersive X-ray spectroscopy revealed considerable pits, cracks, and visible roughness in appearance and an increase in the oxygen-to­carbon (O/C) atomic ratio. Fourier-transform infrared spectroscopy identified characteristic oxygen-containing functional groups and double bonds. X-ray diffraction showed that flame-spraying treatments did not alter the crystal form of polymer, but increased the crystallinity. Higher flame-spraying temperatures resulted in larger oxygen-containing bond indices and lower crystallinity, suggesting a more severe decomposition of PE residual film. The possible volatile gaseous products at different reaction temperatures were predicted using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy (TG-FTIR). Degradation of the PE residual film started at 220 °C, and concentrated release of major products such as long-chain aliphatic hydrocarbons, ketones, and CO2, occurred in the temperature range of 340 °C-440 °C. These results highlighted the effectiveness of the moderate flame-spraying method in accelerating rapid decomposition of residual films, and a flame-spraying temperature range of 220 °C-340 °C should be recommended to avoid potential environmental risks induced by the release of large quantities of degradation products. This study will contribute to enhance our understanding of the thermal oxidative degradation behavior of PE waste and provide a scientific basis for the rapid and clean establishment of PE residual films mitigation in agricultural fields.

6.
Sci Total Environ ; : 176366, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39299327

ABSTRACT

Mangroves are key components of productive ecosystems that provide a multitude of ecosystem goods and services. How these species will respond to future climates with more frequent and severe extreme temperatures has not received much attention. To understand how vulnerable mangroves are to future warming, we quantified photosynthetic heat tolerance and estimated thermal safety margins for thirteen mangrove species from the southwestern Indian coast. We quantified heat tolerance as temperatures that resulted in a 5 % (T5) and 50 % (T50) decline in photosystem II function, and thermal safety margins (TSM) as the difference between T50 and maximum leaf temperatures. T50 ranged from 48.9 °C in Avicennia Marina to 55.3 °C in Bruguiera gymnorhiza, with a mean of 53.3 °C for the thirteen species. Heat tolerance was higher for species with bigger leaves which experience higher leaf temperatures, but was not related to the other leaf traits examined. Heat tolerance was exceptionally high in these mangroves compared to other woody species. With their high tolerance and large safety margins these mangroves may be relatively less vulnerable to future climates with higher temperatures.

7.
Int J Biol Macromol ; : 135949, 2024 Sep 22.
Article in English | MEDLINE | ID: mdl-39317279

ABSTRACT

Previous studies on the modification of fast-growing wood have extensively examined the effects of density and lignin content on the strength and high-temperature properties of modified wood. However, a comprehensive quantitative analysis of their effects on high-temperature performance remains insufficient. To address this knowledge gap, we applied alkali treatment and compression densification to fast-growing poplar, resulting in modified specimens with varying densities and lignin levels. The quantitative effects of density and lignin content on high-temperature properties were meticulously evaluated. Chemical changes were analyzed using Fourier transform infrared spectroscopy (FT-IR), while the mechanical and high-temperature properties were comprehensively assessed. Delignification was found to be positively correlated with treatment duration, with hemicellulose degradation also detected via FT-IR analysis. Significant enhancements were recorded in flexural strength, tensile strength, and modulus of elasticity, accompanied by improvements in ductility ratio and compressive strength. The modified poplar wood exhibited increased thermal stability at elevated temperatures. Furthermore, density and lignin content were identified as significant factors affecting high-temperature performance, establishing minimum density thresholds for various lignin contents in modified poplar wood to ensure optimal performance. This study enhances to the understanding of the intricate relationships among wood properties, modification techniques, and high-temperature performance.

8.
Natl Sci Rev ; 11(10): nwae274, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39301074

ABSTRACT

Compound hot-dry events cause more severe impacts on terrestrial ecosystems than dry events, while the differences in recovery time (ΔRT) between hot-dry and dry events and their contributing factors remain unclear. Both remote sensing observations and eddy covariance measurements reveal that hot-dry events prolong the recovery time compared with dry events, with greater prolongation of recovery time in drylands than in humid regions. Random forest regression modeling demonstrates that the difference in vapor pressure deficit between hot-dry and dry events, with an importance score of 35%, is the major factor contributing to ΔRT. The severity of stomatal restriction exceeds that of non-stomatal limitation, which restricts the vegetation productivity that is necessary for the recovery process. These results emphasize the negative effect of vapor pressure deficit on vegetation recovery during hot-dry events and project an extension of drought recovery time considering elevated vapor pressure deficit in a warming world.

9.
Fish Shellfish Immunol ; : 109913, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39306215

ABSTRACT

Our study aims to examine the changes of long-term high temperature on the mortality and health status of spotted seabass (Lateolabrax maculatus), as well as to screen suitable biomarkers to determine whether the spotted seabass is under heat stress. In this study, 360 juvenile spotted seabass were evenly distributed into three temperature-controlled systems at 27°C (N, normal temperature), 31°C (M, moderate temperature), and 35°C (H, high temperature) for an 8-week aquaculture experiment. The results revealed that 35°C water temperature significantly increased the mortality and the MDA content in tissues (P < 0.05). Meanwhile, 35°C water temperature significantly increased the activity of SOD enzyme and T-AOC capacity in tissues, as well as the expression of hsp60, hsp70, and hsp90 (P < 0.05). Additionally, the expression of nrf2, il1ß, il8, caspase3, caspase9, and bax in the liver significantly increased (P < 0.05), while the expression of keap1, il10, tgfß, and bcl2 decreased significantly (P < 0.05). These results indicate that 35°C water temperature induces oxidative stress in spotted seabass, leading to tissue oxidative damage, promoting inflammation and apoptosis in liver, and increasing mortality. However, the organism compensates by heightening its antioxidant capacity via the Nrf2-Keap1 signaling pathway and inducing high expression of heat shock proteins for self-protection. Furthermore, the alterations in the mRNA level of hsp70 and MDA content in the liver, muscle, and kidney can serve as indicators for evaluating spotted seabass under prolonged heat stress.

10.
Environ Technol ; : 1-16, 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39306691

ABSTRACT

Hydrogen fluoride (HF) corrosion of boiler water-cooled wall pipes at high temperature hinders the co-disposal of fluorinated hazardous wastes and coal by combustion. In this paper, common water-cooled wall pipes (15CrMoG and 20G) were utilized to perform gaseous HF corrosion experiments at high temperature on a horizontal tube furnace. The effects of temperature on HF corrosion of different water-cooled wall pipes in 0.2% HF were investigated. Corrosion kinetics curve was obtained by calculating the mass increase due to corrosion. The microscopic morphology and physical phase composition of water-cooled wall pipes after HF corrosion were analyzed. The corrosion resistances of the two water-cooled wall pipes decrease with increasing the temperature. The corrosion weight gain curves of 15CrMoG and 20G at 550 ℃ are ΔW1.9144 = 0.2100t and ΔW1.8356 = 0.1344t, respectively. The average corrosion rates of 15CrMoG and 20G are 0.0177 and 0.0125 mg/(cm2·h), respectively. The corrosion resistance of 15CrMoG is superior compared to 20G. The HF corrosion at high temperature consists of non-alternating fluorination and oxidation of the metal matrix. This study is of great significance for the protection of boilers with HF corrosion at high temperature.

11.
J Exp Biol ; 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39319428

ABSTRACT

The Arctic is warming three times faster than the global average, imposing challenges to cold-adapted fish, like Arctic char (Salvelinus alpinus). We evaluated stress and metabolic responses of Arctic char to different thermal acclimation scenarios to determine if responses to thermal variation differed from those to stable exposures. Fish were exposed for 7 days to one of 4 treatments: (1) control (12 °C), (2) mean (16 °C), corresponding to the mean temperature of the diel thermal cycle, (3) constant high temperature (20 °C), and (4) diel thermal cycling (12 to 20 °C every 24 h). Exposure to 20 °C causes increases plasma lactate and glucose, an imbalance in antioxidant systems, and oxidative stress in the liver. The 20 °C treatment also elevated fractional rates of protein synthesis and caused oxidative stress in the heart. Stress responses were more pronounced in diel thermal cycling than in mean (16 °C) fish, indicating that peak exposure temperatures or variation are physiologically important. Cortisol was highest in diel thermal cycling fish and oxidative stress was noted in the liver. Gill Na+/K+-ATPase activity was also significantly reduced in diel thermal cycling fish, suggesting gill remodeling in response to an osmoregulatory stress. Exposure to a constant 20 °C, was more challenging than a diel thermal cycle, demonstrating the importance of daily cooling to recovery. Arctic char inhabit a thermally variable environment and understanding how this impacts their physiology will be critical for informing conservation strategies in the context of a rapidly warming Arctic.

12.
Physiol Mol Biol Plants ; 30(9): 1581-1592, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39310701

ABSTRACT

Herbaceous peony (Paeonia lactiflora Pall.) is a widely used famous traditional flower in China. It prefers cold and cool climate, but is not resistant to high temperature during summer in the middle and lower reaches of the Yangtze River. Previously, we found peroxidase (POD) is an important antioxidant enzyme that played an important role in high-temperature tolerance of P. lactiflora. The present study isolated the candidate gene PlPOD45 and verified its function in resisting high-temperature stress. And the results showed that PlPOD45 had an open reading frame of 978 bp that encoded 325 amino acids. Its protein was localized to the cell membrane and cytoplasm. High-temperature stress induced PlPOD45 expression. Heterologous overexpression of PlPOD45 improved plant tolerance to high-temperature stress, decreased reactive oxygen species (ROS) accumulation, relative electrical conductivity and malondialdehyde content, and increased the ratio of variable fluorescence to highest fluorescence and POD activity. Conversely, silencing PlPOD45 in P. lactiflora could decrease POD activity, ROS scavenging capability and cell membrane stability when these plants were exposed to high-temperature stress. These results suggest that PlPOD45 positively regulates high-temperature tolerance through ROS scavenging, which would provide a theoretical basis for improving high-temperature tolerance in P. lactiflora. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01505-x.

13.
J Therm Biol ; 125: 103968, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39312816

ABSTRACT

Environmental high temperature poses a significant threat to human health, however, limited information is available for understanding the relationship between the hot weather and infertility. This study aims to assess the adverse effect of the hot weather to early embryonic cells. Our results indicated that environmental high temperature exposure could cause the decline of early embryo quality and implantation ability. In detail, it led to early embryonic development retardation, embryo degeneration rate increased, the rate of blastocyst and hatching decreased, and reduced the number of implants. And the finding also the impairment of environmental high temperature on early embryonic cells may be due to oxidative damage of DNA caused by ROS, while BER repair ability is decreased, failing to repair oxidative damage of DNA in time, resulting in a large number of early embryonic apoptosis. The work underscored that pregnant women should stay away from high-temperature environments.

14.
Int J Biol Macromol ; 280(Pt 1): 135598, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39276878

ABSTRACT

This study proposed a novel extraction method for soy protein isolate, which involved solid-state fermentation of high-temperature soybean meal. The proteinases secreted by microorganisms acted on the high-temperature soybean meal, making the SPI easier to extract. The study concludes that Bacillus amyloliquefaciens subsp. plantarum CICC 10265 could be used for solid-state fermentation of soybean meal, and the fermentation effect was good, with a yield of 41.91 % for SPI. Compared to the direct extraction of SPI from high-temperature soybean meal, the yield had increased by 130.19 %. Meanwhile, we also conducted research on the losses during the SPI extraction process. Through experiments, the study identified the patterns of protease activity changes and microbial colony growth during solid-state fermentation of soybean meal by Bacillus amyloliquefaciens subsp. plantarum CICC 10265. It was concluded that extracting SPI after 8 h of fermentation is more suitable. The experimental results indicated that the total amino acid content of SPI extracted from fermented soybean meal was 2.1 % higher compared to SPI extracted from low-temperature soybean meal. The extracted SPI also met the microbial standards.

15.
Sci Rep ; 14(1): 21849, 2024 09 19.
Article in English | MEDLINE | ID: mdl-39300156

ABSTRACT

Damage to the development of porcine gametes and embryos caused by high temperatures (HT) is one of the main reasons for the decline in the economic benefits of the livestock industry. Zygotic genome activation (ZGA) marks the beginning of gene expression programs in mammalian pre-implantation embryos. In pigs, ZGA occurs at the 4-cell (4 C) stage, indicating that correct gene expression at this stage plays an important regulatory role in embryonic development. However, the effect of the HT environment on early porcine embryonic development and the RNA expression profile of ZGA remain unclear. In this study, we compared the RNA transcription patterns of porcine 4 C embryos under normal and HT conditions using RNA-seq and identified 326 differentially expressed genes (DEGs). These changes were mainly related to DNA polymerase activity, DNA replication, and nucleotidyltransferase activity. In addition, entries for reverse transcription and endonuclease activity were enriched, indicating that ZGA interfered under HT conditions. Further comparison of the experimental results with the porcine ZGA gene revealed 39 ZGA genes among the DEGs. KEGG and GSEA analysis showed that the oxidative phosphorylation pathway was significantly enriched and signaling pathways related to energy metabolism were significantly downregulated. We also found that NDUFA6 and CDKN1A were located at the center of the protein-protein interaction network diagram of the DEGs. In summary, HT conditions affect mitochondrial function and oxidative phosphorylation levels, and lead to changes in the expression pattern of ZGA in early porcine embryos, with its hub genes NDUFA6 and CDKN1A.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Developmental , Zygote , Animals , Zygote/metabolism , Swine , Hot Temperature , Embryonic Development/genetics , Transcriptome , Genome , Embryo, Mammalian/metabolism
16.
Plant Physiol Biochem ; 216: 109099, 2024 Sep 07.
Article in English | MEDLINE | ID: mdl-39260265

ABSTRACT

Lipids and Ca2+ are involved as intermediate messengers in temperature-sensing signaling pathways. Arbuscular mycorrhizal (AM) symbiosis is a mutualistic symbiosis between fungi and terrestrial plants that helps host plants cope with adverse environmental conditions. Nonetheless, the regulatory mechanisms of lipid- and Ca2+-mediated signaling pathways in mycorrhizal plants under cold and heat stress have not been determined. The present work focused on investigating the lipid- and Ca2+-mediated signaling pathways in arbuscular mycorrhizal (AM) and non-mycorrhizal (NM) roots under temperature stress and determining the role of Ca2+ levels in AM symbiosis and temperature stress tolerance in perennial ryegrass (Lolium perenne L.) Compared with NM plants, AM symbiosis increased phosphatidic acid (PA) and Ca2+ signaling in the roots of perennial ryegrass, increasing the expression of genes associated with low temperature (LT) stress, including LpICE1, LpCBF3, LpCOR27, LpCOR47, LpIRI, and LpAFP, and high temperature (HT) stress, including LpHSFC1b, LpHSFC2b, LpsHSP17.8, LpHSP22, LpHSP70, and LpHSP90, under LT and HT conditions. These effects result in modulated antioxidant enzyme activities, reduced lipid peroxidation, and suppressed growth inhibition caused by LT and HT stresses. Furthermore, exogenous Ca2+ application enhanced AM symbiosis, leading to the upregulation of Ca2+ signaling pathway genes in roots and ultimately promoting the growth of perennial ryegrass under LT and HT stresses. These findings shed light on lipid and Ca2+ signal transduction in AM-associated plants under LT and HT stresses, emphasizing that Ca2+ enhances cold and heat tolerance in mycorrhizal plants.

17.
J Sci Food Agric ; 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39257042

ABSTRACT

BACKGROUND: High temperature stress (HTS) has become a serious threat to rice grain quality and few studies have examined the effects of HTS across multiple stages on rice grain quality. In the present study, we conducted 2 years of HTS treatments under three temperature regimes (32/22 °C, 40/30 °C and 44/34 °C) and HTS durations of 2 days and 4 days at three critical stages: booting, flowering, and a combination of booting and flowering. We employed the heat degree days (HDD) metric, which accounts for both the level and duration of HTS, to quantify the relationships between grain quality traits and HTS. RESULTS: The results revealed the diverse effects of HTS on rice grain quality at different stages, durations and temperature levels. HTS significantly (P < 0.05) reduced grain quality, with the highest sensitivities (reduction per 1 °C day-1 increase in HDD) observed at the flowering stage, followed by the combined and booting stages treatments under mild HTS treatment (40/30 °C). However, under extreme HTS treatments (44/34 °C) for 4 days, rice grains subjected to combined HTS treatment experienced complete mortality. CONCLUSION: Pre-exposed to HTS at the booting stage within a certain intensity can alleviate the adverse effects of post-flowering HTS on grain quality. This provides valuable insights for assessing the potential impact of multiple HTS events on the grain quality under future climate warming. © 2024 Society of Chemical Industry.

18.
Chemistry ; : e202401934, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39251396

ABSTRACT

High-temperature proton exchange membrane fuel cell (HT-PEMFC) based on phosphoric acid doped polybenzimidazole membrane (PBI/PA) operating at 120-200 °C can provide insensitivity to carbon monoxide (CO) and simplified managements of water and heat and thus attract significant global attention. However, one significant drawback is its low utilization of precious metal catalysts resulted from the PA poisoning and inefficient three-phase boundary. Studies of binder materials in catalyst layers for HT-PEMFC are gradually emerging and there are few literature reviews on this important topic. The purpose of this review is to describe the various types of binders based on their molecular structure and electrochemical properties, with particular emphasis on catalyst layer for fuel cells. Importantly, this review provides a better understanding of relationship between fuel cell performance and the gas permeability and conductivity of different binders. Then, future directions of research and development in binder materials of HT-PEMFC are pointed out.

19.
Small ; : e2404310, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39252649

ABSTRACT

Azobenzene (azo)-based photothermal energy storage systems have garnered great interest for their potential in solar energy conversion and storage but suffer from limitations including rely on solvents and specific wavelengths for charging process, short storage lifetime, low heat release temperature during discharging, strong rigidity and poor wearability. To address these issues, an azo-based fabric composed of tetra-ortho-fluorinated photo-liquefiable azobenzene monomer and polyacrylonitrile fabric template is fabricated using electrospinning. This fabric excels in efficient photo-charging (green light) and discharging (blue light) under visible light range, solvent-free operation, long-term energy storage (706 days), and good capacity of releasing high-temperature heat (80-95 °C) at room temperature and cold environments. In addition, the fabric maintains high flexibility without evident loss of energy-storage performance upon 1500 bending cycles, 18-h washing or 6-h soaking. The generated heat from charged fabric is facilitated by the Z-to-E isomerization energy, phase transition latent heat, and the photothermal effect of 420 nm light irradiation. Meanwhile, the temperature of heat release can be personalized for thermal management by adjusting the light intensity. It is applicable for room-temperature thermal therapy and can provide heat to the body in cold environments, that presenting a promising candidate for wearable personal thermal management.

20.
Plant Cell Environ ; 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39254178

ABSTRACT

Although WRKY transcription factors play crucial roles in plant responses to high-temperature stress, little is known about Group IIb WRKY family members. Here, we identified the WRKY-IIb protein PlWRKY47 from herbaceous peony (Paeonia lactiflora Pall.), which functioned as a nuclear-localized transcriptional activator. The expression level of PlWRKY47 was positively correlated with high-temperature tolerance. Silencing of PlWRKY47 in P. lactiflora resulted in the decreased tolerance to high-temperature stress by accumulating reactive oxygen species (ROS). Overexpression of PlWRKY47 improved plant high-temperature tolerance through decreasing ROS accumulation. Moreover, PlWRKY47 directly bound to the promoter of cytosolic glyceraldehyde-3-phosphate dehydrogenase 2 (PlGAPC2) gene and activated its transcription. PlGAPC2 was also positively regulated high-temperature tolerance in P. lactiflora by increasing NAD+ content to inhibit ROS generation. Additionally, PlWRKY47 physically interacted with itself to form a homodimer, and PlWRKY47 could also interact with one Group IIb WRKY family member PlWRKY72 to form a heterodimer, they all promoted PlWRKY47 to bind to and activate PlGAPC2. These data support that the PlWRKY47-PlWRKY47 homodimer and PlWRKY72-PlWRKY47 heterodimer can directly activate PlGAPC2 expression to improve high-temperature tolerance by inhibiting ROS generation in P. lactiflora. These results will provide important insights into the plant high-temperature stress response by WRKY-IIb transcription factors.

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