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A bHLH transcription factor,CsSPT,regulates high-temperature resistance in cucumber 被引量:1
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作者 Yonggui Liang Chenyu Yang +7 位作者 Fangyan Ming Bingwei Yu Zhihua Cheng Yixi Wang Zhengkun Qiu Xiaolan Zhang Bihao Cao Shuangshuang Yan 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期503-514,共12页
High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. How... High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. However, the bHLH TFs responsible for high-temperature tolerance in cucumbers have not been identified. We used transcriptome profiling to screen the high temperature-responsive candidate bHLH TFs in cucumber. Here, we found that the expression of 75 CsbHLH genes was altered under high-temperature stress. The expression of the CsSPT gene was induced by high temperatures in TT(Thermotolerant) cucumber plants. However, the Csspt mutant plants obtained by the CRISPR-Cas9 system showed severe thermosensitive symptoms, including wilted leaves with brown margins and reduced root density and cell activity.The Csspt mutant plants also exhibited elevated H_(2)O_(2) levels and down-regulated photosystem-related genes under normal conditions.Furthermore, there were high relative electrolytic leakage(REC), malondialdehyde(MDA), glutathione(GSH), and superoxide radical(O_(2)^(·-)) levels in the Csspt mutant plants, with decreased Proline content after the high-temperature treatment. Transcriptome analysis showed that the photosystem and chloroplast activities in Csspt mutant plants were extremely disrupted by the high-temperature stress compared with wildtype(WT) plants. Moreover, the plant hormone signal transduction, as well as MAPK and calcium signaling pathways were activated in Csspt mutant plants under high-temperature stress. The HSF and HSP family genes shared the same upregulated expression patterns in Csspt and WT plants under high-temperature conditions. However, most bHLH, NAC, and bZIP family genes were significantly down-regulated by heat in Csspt mutant plants. Thus, these results demonstrated that CsSPT regulated the high-temperature response by recruiting photosynthesis components, signaling pathway molecules, and transcription factors. Our results provide important insights into the heat response mechanism of CsSPT in cucumber and its potential as a target for breeding heat-resistant crops. 展开更多
关键词 CUCUMBER BHLH CsSPT PHOTOSYNTHESIS high temperature
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Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize
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作者 Binbin Li Xianmin Chen +6 位作者 Tao Deng Xue Zhao Fang Li Bingchao Zhang Xin Wang Si Shen Shunli Zhou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期551-565,共15页
The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely de... The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure. 展开更多
关键词 MAIZE high temperature internode growth PLASTICITY plant architecture
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Comprehensive analyses of the proteome and ubiquitome revealed mechanism of high temperature accelerating petal abscission in tree peony
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作者 Chunying Liu Ziqi Liu +4 位作者 Yanchao Yuan Yuxi Zhang Yifu Fang Junqiang Chen Shupeng Gai 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期205-222,共18页
Tree peony(Paeonia suffruticosa Andrews)is a well-known ornamental plant with high economic value,but the short fluorescence is a key obstacle to its ornamental value and industry development.High temperature accelera... Tree peony(Paeonia suffruticosa Andrews)is a well-known ornamental plant with high economic value,but the short fluorescence is a key obstacle to its ornamental value and industry development.High temperature accelerates flower senescence and abscission,but the associated mechanisms are poorly understood.In this study,the tandem mass tag(TMT)proteome and label-free quantitative ubiquitome from tree peony cut flowers treated with 20℃for 0 h(RT0),20℃or 28℃for 60 h(RT60 or HT60)were examined based on morphological observation,respectively.Totally,6970 proteins and 1545 lysine ubiquitinated(Kub)sites in 844 proteins were identified.Hydrophilic residues(such as glutamate and aspartate)neighboring the Kub sites were in preference,and 36.01%of the Kub sites were located on the protein surface.The differentially expressed proteins(DEPs)and Kub-DEPs in HT60 vs RT60 were mainly enriched in ribosomal protein,protein biosynthesis,secondary metabolites biosynthesis,flavonoid metabolism,carbohydrate catabolism,and auxin biosynthesis and signaling revealed by GO and KEGG analysis,accompanying the increase of endogenous abscisic acid(ABA)accumulation and decrease of endogenous indoleacetic acid(IAA)level.Additionally,the expression patterns of six enzymes(SAMS,ACO,YUC,CHS,ANS and PFK)putatively with Kub modifications were analyzed by proteome and real-time quantitative RT-PCR.The cell-free degradation assays showed PsSAMS and PsACO proteins could be degraded via the 26 S proteasome system in tree peony flowers.Finally,a working model was proposed for the acceleration of flower senescence and abscission by high temperature.In summary,all results contributed to understanding the mechanism of flower senescence induced by high temperature and prolonging fluorescence in tree peony. 展开更多
关键词 Tree peony PROTEOME Ubiquitome high temperature Flower senescence
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Spalling characteristics of high-temperature treated granitic rock at different strain rates
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作者 L.F.Fan Q.H.Yang X.L.Du 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1280-1288,共9页
The dynamic spalling characteristics of rock are important for stability analysis in rock engineering.This paper presented an experimental investigation on the dynamic spalling characteristics of granite with differen... The dynamic spalling characteristics of rock are important for stability analysis in rock engineering.This paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different temperatures.The dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain rate.The results show that the spalling strength of granite decreases with increasing temperature.Moreover,the spalling strength of granite with a higher strain rate is larger than that with a lower strain rate.The proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate. 展开更多
关键词 Dynamic spalling characteristics high temperature Strain rate Dynamic loading GRANITE
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Higher Grain-Filling Rate in Inferior Spikelets of Tolerant Rice Genotype Offset Grain Yield Loss under Post-Anthesis High Night Temperatures
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作者 Nitin SHARMA Bhupinder SINGH +6 位作者 Subbaiyan Gopala KRISHNAN Haritha BOLLINEDI Pranab Kumar MANDAL Milan Kumar LAL Prakash Kumar JHA P.V.Vara PRASAD Anjali ANAND 《Rice science》 SCIE CSCD 2024年第5期572-586,I0059-I0061,共18页
Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could ... Increased nighttime respiratory losses decrease the amount of photoassimilates available for plant growth and yield. We hypothesized that the increased respiratory carbon loss under high night temperatures(HNT) could be compensated for by increased photosynthesis during the day following HNT exposure. Two rice genotypes, Vandana(HNT-sensitive) and Nagina 22(HNT-tolerant), were exposed to HNT(4 ℃ above the control) from flowering to physiological maturity. They were assessed for alterations in the carbon balance of the source(flag leaf) and its subsequent impact on grain filling dynamics and the quality of spatially differentiated sinks(superior and inferior spikelets). Both genotypes exhibited significantly higher night respiration rates. However, only Nagina 22 compensated for the high respiration rates with an increased photosynthetic rate, resulting in a steady production of total dry matter under HNT. Nagina 22 also recorded a higher grain-filling rate, particularly at 5 and 10 d after flowering, with 1.5- and 4.0-fold increases in the translocation of ^(14)C sugars to the superior and inferior spikelets, respectively. The ratio of photosynthetic rate to respiratory rate on a leaf area basis was negatively correlated with spikelet sterility, resulting in a higher filled spikelet number and grain weight per plant, particularly for inferior grains in Nagina 22. Grain quality parameters such as head rice recovery, high-density grains, and gelatinization temperature were maintained in Nagina 22. An increase in the rheological properties of rice flour starch in Nagina 22 under HNT indicated the stability of starch and its ability to reorganize during the cooling process of product formation. Thus, our study showed that sink adjustments between superior and inferior spikelets favored the growth of inferior spikelets, which helped to offset the reduction in grain weight under HNT in the tolerant genotype Nagina 22. 展开更多
关键词 high night temperature inferior grain pasting property radiolabeled sugar superior grain
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Resistance index and browning mechanism of apple peel under high temperature stress
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作者 Hui Wang Shuhui Zhang +8 位作者 Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen Wenmin Fan Lulong Sun Zhengyang Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期305-317,共13页
Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect no... Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and yield.We took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was monitored.The results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 days.To determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different temperatures.It was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype appeared.Meanwhile,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing temperature.The content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in apple.Furthermore,transient and stable MdPPO1 overexpression significantly promoted peel browning.The transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature stress.Thus,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browning phenotype that provides a scientific theoretical basis for the selection of high temperature-resistant varieties and apple cultivation and management in the future. 展开更多
关键词 Malus domestica Borkh high temperature stress PEEL BROWNING MdPPO1
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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability
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作者 Ming-Wei Zhao Zhen-Feng Ma +5 位作者 Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-Long Cheng Xiang-Yu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1113-1121,共9页
Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performa... Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications. 展开更多
关键词 Unconventional resources Polymeric drag reducing agent Slickwater high drag reduction rate temperature resistance
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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM
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作者 WANG Yanxia YANG Lisha +1 位作者 HUANG Xiaoyuan ZHOU Ruliang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2025-2042,共18页
Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are n... Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources. 展开更多
关键词 high temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection
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Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications
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作者 Jinge Liu Bangzhao Yin +7 位作者 Fei Song Bingchuan Liu Bo Peng Peng Wen Yun Tian Yufeng Zheng Xiaolin Ma Caimei Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期940-953,共14页
Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples... Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications. 展开更多
关键词 Laser powder bed fusion Biodegradable magnesium alloy high temperature oxidation Corrosion resistance WE43.
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High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera
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作者 Hongda Deng Xiaoyu Zhang +5 位作者 Song Sheng Yuxun Huang Ziqi Ye Tongyue Zhang Xing Liu Zhiqiang Han 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期879-896,共18页
Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce th... Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature treatment.This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in C.oleifera.We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n pollen.Through the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell plate.Based on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were identified.After male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly upregulated.We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell plate.Furthermore,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n pollen.Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C.oleifera. 展开更多
关键词 Camellia oleifera Pollen mother cells(PMCs) high temperature MEIOSIS 2n pollen CoPGX3
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Anisotropic strength,deformation and failure of gneiss granite under high stress and temperature coupled true triaxial compression
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作者 Hongyuan Zhou Zaobao Liu +2 位作者 Fengjiao Liu Jianfu Shao Guoliang Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期860-876,共17页
The anisotropic mechanical behavior of rocks under high-stress and high-temperature coupled conditions is crucial for analyzing the stability of surrounding rocks in deep underground engineering.This paper is devoted ... The anisotropic mechanical behavior of rocks under high-stress and high-temperature coupled conditions is crucial for analyzing the stability of surrounding rocks in deep underground engineering.This paper is devoted to studying the anisotropic strength,deformation and failure behavior of gneiss granite from the deep boreholes of a railway tunnel that suffers from high tectonic stress and ground temperature in the eastern tectonic knot in the Tibet Plateau.High-temperature true triaxial compression tests are performed on the samples using a self-developed testing device with five different loading directions and three temperature values that are representative of the geological conditions of the deep underground tunnels in the region.Effect of temperature and loading direction on the strength,elastic modulus,Poisson’s ratio,and failure mode are analyzed.The method for quantitative identification of anisotropic failure is also proposed.The anisotropic mechanical behaviors of the gneiss granite are very sensitive to the changes in loading direction and temperature under true triaxial compression,and the high temperature seems to weaken the inherent anisotropy and stress-induced deformation anisotropy.The strength and deformation show obvious thermal degradation at 200℃due to the weakening of friction between failure surfaces and the transition of the failure pattern in rock grains.In the range of 25℃ 200℃,the failure is mainly governed by the loading direction due to the inherent anisotropy.This study is helpful to the in-depth understanding of the thermal-mechanical behavior of anisotropic rocks in deep underground projects. 展开更多
关键词 Anisotropic strength and deformation True triaxial compression Thermal mechanical coupling Deep rock mechanics high temperature rock mechanics
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Intermolecular Acid-Base-Pairs Containing Poly(p-Terphenyl-co-lsatin Piperidinium)for High Temperature Proton Exchange Membrane Fuel Cells
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作者 Xiaofeng Hao Zhen Li +6 位作者 Min Xiao Zhiheng Huang Dongmei Han Sheng Huang Wei Liu Shuanjin Wang Yuezhong Meng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期406-414,共9页
How to optimize and regulate the distribution of phosphoric acid in matrix,and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane(HT-PEMs)fuel cell are ... How to optimize and regulate the distribution of phosphoric acid in matrix,and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane(HT-PEMs)fuel cell are significant challenges.Herein,bifunctional poly(p-terphenyl-co-isatin piperidinium)copolymer with tethered phosphonic acid(t-PA)and intrinsic tertiary amine base groups are firstly prepared and investigated as HT-PEMs.The distinctive architecture of the copolymer provides a well-designed platform for rapid proton transport.Protons not only transports through the hydrogen bond network formed by the adsorbed free phosphoric acid(f-PA)anchored by the tertiary amine base groups,but also rely upon the proton channel constructed by the ionic cluster formed by the t-PA aggregation.Thorough the design of the structure,the bifunctional copolymers with lower PA uptake level(<100%)display prominent proton conductivities and peak power densities(99 mS cm^(-1),812 mW cm^(-2)at 160℃),along with lower PA leaching and higher voltage stability,which is a top leading result in disclosed literature.The results demonstrate that the design of intermolecular acid-base-pairs can improve the proton conductivity without sacrificing the intrinsic chemical stability or mechanical property of the thin membrane,realizing win-win demands between the mechanical robustness and electrochemical properties of HT-PEMs. 展开更多
关键词 bifunctional copolymer high temperature proton exchange membrane intermolecular acid-base-pairs phosphonic acid retention phosphonic acid uptake level
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Short communication:Extreme glacier mass loss triggered by high temperature and drought during hydrological year 2022/2023 in Qilian Mountains
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作者 JiZu Chen XingYu Xue WenTao Du 《Research in Cold and Arid Regions》 CSCD 2024年第1期1-4,共4页
In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over... In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over the Bailanghe Glacier No.12 in the middle of Qilian Mountains.The temperature during 2022–2023 reached the highest value ever recorded,second only to 2022,while at the same time the precipitation amount was less compared to other year since 2000,which together led to the strongest glacier mass loss during 2022–2023.The atmospheric circulation analysis shows that the high temperature in the Qilian Mountains in 2023 was jointly caused by the Arctic air mass and East Asian monsoon. 展开更多
关键词 Bailanghe Glacier No.21 Glacier mass loss Extreme high temperature Atmospheric circulation
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Spatial Optimization Strategies for High Temperature Heat Exposure Based on Thermally Vulnerable Populations and Case Studies
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作者 XIA Xiaoya YANG Xin ZHANG Qi 《Journal of Landscape Research》 2024年第2期1-5,14,共6页
The objective of this study is to investigate the factors that contribute to brittleness and to identify strategies for mitigating these factors in populations with varying degrees of thermal vulnerability,based on th... The objective of this study is to investigate the factors that contribute to brittleness and to identify strategies for mitigating these factors in populations with varying degrees of thermal vulnerability,based on the potential impact of extreme heat exposure on human survival and habitability.The physiological condition of lower adaptability to high temperature environments and the assessment of individuals who may have higher tolerance time in high temperature environments based on spatial perspectives suggest the need for targeted spatial optimization strategies for commuters and disadvantaged populations.This is demonstrated through a case study.These optimization measures encompass a variety of aspects,including the integration of transportation systems,the expansion of grey space corridors,the improvement of green space layout,and the implantation of green infrastructure.The study aims to reduce the exposure time of thermally vulnerable individuals to high temperature environments through spatial optimization strategies,to enhance the resilience of urban green spaces to heat stress,and to reduce the probability of heat-wave occurrence. 展开更多
关键词 Thermal vulnerability EXPOSURE high temperature environment Spatial optimization
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High Temperature Rheological Performance of Graphene Modified Rubber Asphalt
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作者 Heyuan GUO Chunhua LI +3 位作者 Xin ZHAO Yinghua YUAN Shaoqi TANG Yongjun MENG 《Research and Application of Materials Science》 2024年第1期9-15,共7页
To elucidate the high temperature rheological capability of graphene modified rubber asphalt,three contents of graphene and crumb rubber were prepared by a combination of mechanical agitation and high speed shearing m... To elucidate the high temperature rheological capability of graphene modified rubber asphalt,three contents of graphene and crumb rubber were prepared by a combination of mechanical agitation and high speed shearing machine,then used dynamic shear rheological test(DSR)and multiple stress creep recovery(MSCR)tests to evaluate.The hardness and softening point with rotational viscosity of samples raised with the addition of graphene,especially the addition of 0.04%.Dynamic shear rheological test revealedthat the dynamic shear modulus G*,rutting factor G*/Sin δ,and zero shear viscosity(ZSV)of graphene-modified rubber asphalt were greatly influenced along with graphene-increased,on the contrary,phase angle δ which characterize the viscoelastic ratio of asphalt decreased.Multiple stress creep recovery(MSCR)tests showed that the graphene-enhanced rubber asphalt had high-temperature stability through non-recoverable creep compliance(Jnr).Based on these findings,graphene-modified rubber asphalt binders with the addition of 0.04% graphene had good viscoelastic properties as well as high temperature rutting resistance performance.In the meantime,G*/Sin δ,ZSV,and Jnr100,Jnr3200 have good correlation,which can reveal the excellent high-temperature stability performance of asphalt. 展开更多
关键词 GRAPHENE high temperature rheological properties MSCR Zero shear viscosity RUTTING
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Temperature dependence of mechanical properties and damage evolution of hot dry rocks under rapid cooling
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作者 Longjun Dong Yihan Zhang +2 位作者 Lichang Wang Lu Wang Shen Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期645-660,共16页
Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoust... Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoustic emission(AE)characteristics and mechanical parameters of granodiorite and granite after heating and water cooling by uniaxial compression and variable-angle shear tests under different temperature gradients.We identify their changes in mesostructure and mineral composition with electron probe microanalysis and scanning electron microscopy.Results show that these two hot dry rocks have similar diagenetic minerals and microstructure,but show significantly different mechanical and acoustic characteristics,and even opposing evolution trends in a certain temperature range.At the temperatures ranging from 100℃to 500℃,the compressive and shear mechanical properties of granodiorite switch repeatedly between weakening and strengthening,and those of granite show a continuous weakening trend.At 600℃,both rocks exhibit a deterioration of mechanical properties.The damage mode of granite is characterized by initiating at low stress,exponential evolutionary activity,and intensified energy release.In contrast,granodiorite exhibits the characteristics of initiating at high stress,volatile evolutionary activity,and intermittent energy release,due to its more stable microstructure and fewer thermal defects compared to granite.As the temperature increases,the initiation and propagation of secondary cracks in granodiorite are suppressed to a certain extent,and the seismicity and brittleness are enhanced.The subtle differences in grain size,microscopic heterogeneity,and mineral composition of the two hot dry rocks determine the different acoustic-mechanical characteristics under heating and cooling,and the evolution trends with temperature.These findings are of great significance for the scientific and efficient construction of rock mass engineering by rationally utilizing different rock strata properties. 展开更多
关键词 Hot dry rock Acoustic emission Mechanical properties high temperature DAMAGE
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Global Burden of Cardiovascular Disease Attributable to High Temperature in 204 Countries and Territories from 1990 to 2019 被引量:3
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作者 HONG Le YAN Miao Miao +4 位作者 ZHANG Yun Quan WANG Kai WANG Ya Qi LUO Si Qi WANG Fang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第3期222-230,共9页
Objective This study aimed to estimate spatiotemporal variations of global heat-related cardiovascular disease(CVD)burden from 1990 to 2019.Methods Data on the burden of heat-related CVD were derived from the Global B... Objective This study aimed to estimate spatiotemporal variations of global heat-related cardiovascular disease(CVD)burden from 1990 to 2019.Methods Data on the burden of heat-related CVD were derived from the Global Burden of Disease Study 2019.Deaths and disability-adjusted life years(DALYs)were used to quantify heat-induced CVD burden.We calculated the age-standardized mortality rate(ASMR)and DALY rate(ASDR)per 100,000population to compare this burden across regions.Generalized linear models were applied to evaluate estimated annual percentage changes(EAPC)for temporal trends from 1990 to 2019.The correlation between the socio-demographic index(SDI)and age-standardized rate was measured using the Spearman rank test.Results Heat-induced CVD caused approximately 90 thousand deaths worldwide in 2019.Global ASMR and ASDR of heat-related CVD in 2019 were 1.17[95%confidence interval(CI):0.13-1.98]and 25.59(95%CI:2.07-44.17)per 100,000 population,respectively.The burden was significantly increased in middle and low-SDI regions and slightly decreased in high-SDI regions from 1990 to 2019.ASMR showed an upward trend,with the most considerable increase in low-latitude countries.We observed a negative correlation between SDI and EAPC in ASMR(rs=-0.57,P<0.01)and ASDR(rs=-0.59,P<0.01)among204 countries.Conclusion Heat-attributable CVD burden substantially increased in most developing countries and tropical regions. 展开更多
关键词 high temperature Cardiovascular disease Global disease burden Climate change
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Room Temperature Synthesis of Vertically Aligned Amorphous Ultrathin NiCo-LDH Nanosheets Bifunctional Flexible Supercapacitor Electrodes
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作者 Kwadwo Asare Owusu Zhaoyang Wang +7 位作者 Ali Saad Felix Ofori Boakye Muhammad Asim Mushtaq Muhammad Tahir Ghulam Yasin Dongqing Liu Zhengchun Peng Xingke Cai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期277-286,共10页
Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets ... Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets vertically aligned on activated carbon cloth substrate,which was in situ transformed from Co-metal-organic framework materials nano-columns by a simple ion exchange process at room temperature.Due to the amorphous and vertically aligned ultrathin structure of NiCo-LDH,the NiCo-LDH/activated carbon cloth composites present high areal capacities of 3770 and 1480 mF cm^(-2)as cathode and anode at 2 mA cm^(-2),and 79.5%and 80%capacity have been preserved at 50 mA cm^(-2).In the meantime,they all showed excellent cycling performance with negligible change after>10000 cycles.By fabricating them into an asymmetric supercapacitor,the device achieves high energy densities(5.61 mWh cm^(-2)and 0.352 mW cm^(-3)).This work provides an innovative strategy for simplifying the design of supercapacitors as well as providing a new understanding of improving the rate capabilities/cycling stability of NiCo-LDH materials. 展开更多
关键词 amorphous nanosheets aqueous supercapacitor high volumetric/areal energy density NiCo-LDH room temperature synthesis
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Various admixtures to mitigate the long-term strength retrogression of Portland cement cured under high pressure and high temperature conditions 被引量:2
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作者 Jiankun Qin Xueyu Pang +2 位作者 Ashok Santra Guodong Cheng Hailong Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期191-203,共13页
In order to investigate the problem of long-term strength retrogression in oil well cement systems exposed to high pressure and high temperature(HPHT)curing conditions,various influencing factors,including cement sour... In order to investigate the problem of long-term strength retrogression in oil well cement systems exposed to high pressure and high temperature(HPHT)curing conditions,various influencing factors,including cement sources,particle sizes of silica flour,and additions of silica fume,alumina,colloidal iron oxide and nano-graphene,were investigated.To simulate the environment of cementing geothermal wells and deep wells,cement slurries were directly cured at 50 MPa and 200?C.Mineral compositions(as determined by X-ray diffraction Rietveld refinement),water permeability,compressive strength and Young’s modulus were used to evaluate the qualities of the set cement.Short-term curing(2e30 d)test results indicated that the adoption of 6 m m ultrafine crystalline silica played the most important role in stabilizing the mechanical properties of oil well cement systems,while the addition of silica fume had a detrimental effect on strength stability.Long-term curing(2e180 d)test results indicated that nano-graphene could stabilize the Young’s modulus of oil well cement systems.However,none of the ad-mixtures studied here can completely prevent the strength retrogression phenomenon due to their inability to stop the conversion of amorphous to crystalline phases. 展开更多
关键词 high pressure and high temperature(HPHT) Strength retrogression Young’s modulus Water permeability Rietveld method
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Genetic variability predicting breeding potential of upland cotton(Gossypium hirsutum L.)for high temperature tolerance 被引量:2
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作者 FAROOQ Amjad SHAKEEL Amir +5 位作者 SAEED Asif FAROOQ Jehanzeb RIZWAN Muhammad CHATTHA Waqas Shafqat SARWAR Ghulam RAMZAN Yasir 《Journal of Cotton Research》 CAS 2023年第2期81-97,共17页
Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hy... Background High temperature stress at peak flowering stage of cotton is a major hindrance for crop potential.This study aimed to increase genetic divergence regarding heat tolerance in newly developed cultivars and hybrids.Fifty cotton genotypes and 40 F1(hybrids)were tested under field conditions following the treatments,viz.,high temperature stress and control at peak flowering stage in August and October under April and June sowing,respectively.Results The mean squares revealed significant differences among genotypes,treatments,genotype×treatment for relative cell injury,chlorophyll contents,canopy temperature,boll retention and seed cotton yield per plant.The genetic diversity among 50 genotypes was analyzed through cluster analysis and heat susceptibility index(HSI).The heat tolerant genotypes including FH-Noor,NIAB-545,FH-466,FH-Lalazar,FH-458,NIAB-878,IR-NIBGE-8,Weal-AGShahkar,and heat sensitive,i.e.,CIM-602,Silky-3,FH-326,SLH-12 and FH-442 were hybridized in line×tester fashion to produce F1 populations.The breeding materials’populations(40 F1)revealed higher specific combining ability variances along with dominance variances,decided the non-additive type gene action for all the traits.The best general combining ability effects for most of the traits were displayed by the lines,i.e.,FH-Lalazar,NIAB-878 along with testers FH-326 and Silky-3.Specific combining ability effects and better-parent heterosis were showed by the crosses,viz.,FH-Lalazar×Silky-3,FH-Lalazar×FH-326,NIAB-878×Silky-3,and NIAB-878×FH-326 for seed cotton yield and yield contributing traits under high temperature stress.Conclusion Heterosis breeding should be carried out in the presence of non-additive type gene action for all the studied traits.The best combiner parents with better-parent heterosis may be used in crossing program to develop high yielding cultivars,and hybrids for high temperature stress tolerance. 展开更多
关键词 high temperature Upland cotton Peak flowering HETEROSIS Gene action Combining ability
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