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Drug-delivery strategies using biomaterials in the field of nerve regeneration
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作者 Linbin Xu chao zhou +1 位作者 Xu Wang Cunyi Fan 《Neural Regeneration Research》 2026年第5期1738-1763,共26页
Neural injuries can cause considerable functional impairments,and both central and peripheral nervous systems have limited regenerative capacity.The existing conventional pharmacological treatments in clinical practic... Neural injuries can cause considerable functional impairments,and both central and peripheral nervous systems have limited regenerative capacity.The existing conventional pharmacological treatments in clinical practice show poor targeting,rapid drug clearance from the circulatory system,and low therapeutic efficiency.Therefore,in this review,we have first described the mechanisms underlying nerve regeneration,characterized the biomaterials used for drug delivery to facilitate nerve regeneration,and highlighted the functionalization strategies used for such drug-delivery systems.These systems mainly use natural and synthetic polymers,inorganic materials,and hybrid systems with advanced drug-delivery abilities,including nanoparticles,hydrogels,and scaffoldbased systems.Then,we focused on comparing the types of drug-delivery systems for neural regeneration as well as the mechanisms and challenges associated with targeted delivery of drugs to facilitate neural regeneration.Finally,we have summarized the clinical application research and limitations of targeted delivery of these drugs.These biomaterials and drug-delivery systems can provide mechanical support,sustained release of bioactive molecules,and enhanced intercellular contact,ultimately reducing cell apoptosis and enhancing functional recovery.Nevertheless,immune reactions,degradation regulation,and clinical translations remain major unresolved challenges.Future studies should focus on optimizing biomaterial properties,refining delivery precision,and overcoming translational barriers to advance these technologies toward clinical applications. 展开更多
关键词 BIOMATERIALS clinical trial drug drug-delivery strategy drug-loading strategy drug-release strategy nerve regeneration peripheral nerve RNA tissue engineering
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Accurate prediction of magnetocaloric effect in NiMn-based Heusler alloys by prioritizing phase transitions through explainable machine learning 被引量:2
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作者 Yi-Chuan Tang Kai-Yan Cao +7 位作者 Ruo-Nan Ma Jia-Bin Wang Yin Zhang Dong-Yan Zhang chao zhou Fang-Hua Tian Min-Xia Fang Sen Yang 《Rare Metals》 2025年第1期639-651,共13页
With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase t... With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase transitions into account,and as a result,the predictions are usually not accurate enough.In this context,we have established an explicable relationship between alloy compositions and phase transition by feature imputation.A facile machine learning is proposed to screen candidate NiMn-based Heusler alloys with desired magnetic entropy change and magnetic transition temperature with a high accuracy R^(2)≈0.98.As expected,the measured properties of prepared NiMn-based alloys,including phase transition type,magnetic entropy changes and transition temperature,are all in good agreement with the ML predictions.As well as being the first to demonstrate an explicable relationship between alloy compositions,phase transitions and magnetocaloric properties,our proposed ML model is highly predictive and interpretable,which can provide a strong theoretical foundation for identifying high-performance magnetocaloric materials in the future. 展开更多
关键词 NiMn-based Heusler materials Phase transition-type Machine learning Magnetocaloric effect Composition design
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Collapse of Meilong Expressway as Seen from Space:Detecting Precursors of Failure with Satellite Remote Sensing 被引量:1
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作者 Zhuge Xia chao zhou +4 位作者 Wandi Wang Mimi Peng Dalu Dong Xiufeng He Guangchao Tan 《Journal of Earth Science》 2025年第2期835-838,共4页
INTRODUCTION.On May 1st,2024,around 2:10 a.m.,a catastrophic collapse occurred along the Meilong Expressway near Meizhou City,Guangdong Province,China,at coordinates 24°29′24″N and 116°40′25″E.This colla... INTRODUCTION.On May 1st,2024,around 2:10 a.m.,a catastrophic collapse occurred along the Meilong Expressway near Meizhou City,Guangdong Province,China,at coordinates 24°29′24″N and 116°40′25″E.This collapse resulted in a pavement failure of approximately 17.9 m in length and covering an area of about 184.3 m^(2)(Chinanews,2024). 展开更多
关键词 failure detection satellite remote sensing pavement failure Meilong Expressway meilong expressway COLLAPSE precursors
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New applications of clioquinol in the treatment of inflammation disease by directly targeting arginine 335 of NLRP3 被引量:1
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作者 Peipei Chen Yunshu Wang +6 位作者 Huaiping Tang chao zhou Zhuo Liu Shenghan Gao Tingting Wang Yun Xu Sen-Lin Ji 《Journal of Pharmaceutical Analysis》 2025年第1期151-171,共21页
The NOD-like receptor protein 3(NLRP3)inflammasome is essential in innate immune-mediated inflammation,with its overactivation implicated in various autoinflammatory,metabolic,and neurodegenerative diseases.Pharmacolo... The NOD-like receptor protein 3(NLRP3)inflammasome is essential in innate immune-mediated inflammation,with its overactivation implicated in various autoinflammatory,metabolic,and neurodegenerative diseases.Pharmacological inhibition of NLRP3 offers a promising treatment strategy for inflammatory conditions,although no medications targeting the NLRP3 inflammasome are currently available.This study demonstrates that clioquinol(CQ),a clinical drug with chelating properties,effectively inhibits NLRP3 activation,resulting in reduced cytokine secretion and cell pyroptosis in both human and mouse macrophages,with a half maximal inhibitory concentration(IC_(50))of 0.478 mM.Additionally,CQ mitigates experimental acute peritonitis,gouty arthritis,sepsis,and colitis by lowering serum levels of interleukin-1β(IL-1β),IL-6,and tumor necrosis factor-α(TNF-α).Mechanistically,CQ covalently binds to Arginine 335(R335)in the NACHT domain,inhibiting NLRP3 inflammasome assembly and blocking the interaction between NLRP3 and its component protein.Collectively,this study identifies CQ as an effective natural NLRP3 inhibitor and a potential therapeutic agent for NLRP3-driven diseases. 展开更多
关键词 CLIOQUINOL NLRP3 inflammasome NACHT domain Sepsis PERITONITIS COLITIS
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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm
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作者 chao zhou Narisu Wang +1 位作者 Fuyin Ni Wenchao Zhang 《Energy Engineering》 EI 2025年第1期265-284,共20页
Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,th... Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island modes.In response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization algorithm.The proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop control.Then,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control strategy.Precise pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid voltage.Additionally,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee algorithm.These operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load transients.This strategy effectively mitigated transient voltage and current surges during mode transitions.Consequently,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid inverter.The enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability. 展开更多
关键词 Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching
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Slope Deformation Analysis of Muyubao Landslide,China,Using Lutan-1 InSAR Data
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作者 Wandi Wang Mahdi Motagh +5 位作者 chao zhou Zhuge Xia Sen Lyu Mimi Peng Guangchao Tan Chengjin Yan 《Journal of Earth Science》 2025年第6期2825-2829,共5页
0 INTRODUCTION Synthetic Aperture Radar(SAR)remote sensing,particularly with the C-band Sentinel-1 mission,has been widely used for landslide displacement analysis due to its high spatial resolution and revisit freque... 0 INTRODUCTION Synthetic Aperture Radar(SAR)remote sensing,particularly with the C-band Sentinel-1 mission,has been widely used for landslide displacement analysis due to its high spatial resolution and revisit frequency(Zhou et al.,2024;Dai et al.,2021).However,in densely vegetated or humid mountainous regions such as the Three Gorges Reservoir(TGR),C-band signals suffer from temporal decorrelation,limiting their effectiveness for landslide monitoring. 展开更多
关键词 landslide displacement analysis remotely sensing LUTAN INSAR slope deformation C band Sentinel synthetic aperture radar landslide monitoring synthetic aperture radar sar remote sensingparticularly
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Effects of RNA m^(6)A on the formation of multi-petalization in Magnolia wufengensis:Mechanistic insights and gene expression analysis
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作者 Cunjie Li Huarong Li +7 位作者 Jiang Ma Xiaoning Fan Yanjun Cai Liyuan Chen Hanlin zhou Hongwei Liang chao zhou Faju Chen 《Horticultural Plant Journal》 2025年第4期1653-1668,共16页
N^(6)-Methyladenosine(m^(6)A)is the most common modification in the transcriptome of biological RNA and plays roles that include maintaining the stability and transportation of mRNA,mRNA precursor shearing,polyadenyla... N^(6)-Methyladenosine(m^(6)A)is the most common modification in the transcriptome of biological RNA and plays roles that include maintaining the stability and transportation of mRNA,mRNA precursor shearing,polyadenylation,and the initiation of translation.With the improving understanding of RNA methylation,m^(6)A modification is known to play vital roles in plant development and growth.The multi-petalization of flowering plants has high ornamental and research value in horticultural landscapes.However,the mechanism of RNA methylation in flower formation in Magnolia wufengensis,a classical multi-petalizational plant,remains unclear.This study compared and analyzed RNA m^(6)A methylation and the transcriptome in floral buds of two varieties with large differences in tepal number at the early stage of development.It was found that the degree of RNA m^(6)A methylation and relative expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9 in‘Jiaodan’with 36 tepals were significantly higher than those in‘Jiaohong’with 9 tepals during the development of floral organ primordia.Combined with quantitative real-time PCR,the expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9were positively correlated with the number of tepals.Transgenic experiments showed that MawuAGL6-1/2,and MawuPI-4 can increase the number of petals in Arabidopsis.Moreover,MawuAGL6-2 and MawuPI-4 can restore the missing petal phenotype of mutant Arabidopsis.Yeast two hybrid and yeast three hybrid indicated that MawuAGL6-2,MawuAP3-1/2,and MawuPI-4 could interact with each other under the mediation of the class E protein MawuAGL9.Based on these results,it is hypothesized that m^(6)A methylation influences the multi-petalization of Magnolia wufengensis by affecting the expression levels of MawuAGL6-2,MawuAP3-1/2,MawuPI-4,and MawuAGL9.These findings provide a better understanding of the molecular mechanisms of epigenetic modifications in flower developmental diversity. 展开更多
关键词 Magnolia wufengensis Epigenetic regulation m^(6)A methylation Gene expression Floral development Multi-petalization
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High-performance magnetostrictive Fe_(83)Ga_(17) alloy with excellent mechanical properties induced by interstitial doping of small-radius boron atoms
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作者 Kun Wang Qi-Zhong Zhao +10 位作者 Tie-Yan Chang Fang-Hua Tian Jia-Le Guo Zhi-Yong Dai Jie Liu Yi-Chuan Tang Si-Ying Yu Yin Zhang chao zhou Kai-Yan Cao Sen Yang 《Rare Metals》 2025年第10期7772-7783,共12页
Excellent magnetostrictive properties and processability are the two most important key factors for the practical application of magnetostrictive materials and research directions of continuous concern.In this study,w... Excellent magnetostrictive properties and processability are the two most important key factors for the practical application of magnetostrictive materials and research directions of continuous concern.In this study,we significantly improved the magnetostriction,ductility,and tensile strength of Fe_(83)Ga_(17)B_(x)(x=0,1,2,3,and 4)alloys by adjusting the small-radius boron(B)doping concentration.When x=3,the maximum magnetostriction value reached 193 ppm,approximately twice that of the undoped alloy(x=0),while the ultimate tensile strength and elongation increased by 147%and 238%,respectively,compared to Fe_(83)Ga_(17)alloys.Both first-principles calculations and experimental results indicate that B doping facilitates the alignment of FeGa crystal growth direction with the easy magnetization axis,thereby significantly improving the magnetostrictive properties of the alloy.Additionally,increasing B content progressively refines the grain size and promotes Fe_(2)B phase formation,thereby enhancing both strength and toughness.At x=3,the material exhibits the highest saturation magnetization and the lowest coercivity.Therefore,the results show that doping small-radius atoms in the interstitial sites can effectively enhance the magnetostrictive and mechanical properties of FeGa materials.This work offers a promising strategy for designing magnetostrictive materials with superior overall properties. 展开更多
关键词 Fe-Ga alloys MAGNETOSTRICTION Mechanical property First-principles calculations Crystallographic orientation
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Performance of the First 80 kA HTS CICC for High-Field Application in Future Fusion Reactors
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作者 Huan Jin Guanyu Xiao +20 位作者 chao zhou Chuanyi Zhao Shijie Shi Haihong Liu Fang Liu Huajun Liu Yu Wu Zuojiafeng Wu Hugues Bajas Jack Greenwood Mattia Ortino Kamil Sedlak Valentina Corato Richard Kamendje Alexandre Torre Arend Nijhuis Giulio Anniballi Arnaud Devred Jinggang Qin Yuntao Song Jiangang Li 《Engineering》 2025年第12期182-190,共9页
A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the n... A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications. 展开更多
关键词 Fusion magnet High-temperature superconductor REBCO CICC Electromagnetic and thermal load Operational stability
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13-Docosenamide Enhances Oligodendrocyte Precursor Cell Differentiation via USP33-Mediated Deubiquitination of CNR1 in Chronic Cerebral Hypoperfusion
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作者 Yuhao Xu Yi Tan +7 位作者 Zhi Zhang Duo Chen chao zhou Liang Sun Shengnan Xia Xinyu Bao Haiyan Yang Yun Xu 《Neuroscience Bulletin》 2025年第11期1939-1956,共18页
Chronic cerebral hypoperfusion leads to white matter injury(WMI),which plays a significant role in contributing to vascular cognitive impairment.While 13-docosenamide is a type of fatty acid amide,it remains unclear w... Chronic cerebral hypoperfusion leads to white matter injury(WMI),which plays a significant role in contributing to vascular cognitive impairment.While 13-docosenamide is a type of fatty acid amide,it remains unclear whether it has therapeutic effects on chronic cerebral hypoperfusion.In this study,we conducted bilateral common carotid artery stenosis(BCAS)surgery to simulate chronic cerebral hypoperfusion-induced WMI and cognitive impairment.Our findings showed that 13-docosenamide alleviates WMI and cognitive impairment in BCAS mice.Mechanistically,13-docosenamide specifically binds to cannabinoid receptor 1(CNR1)in oligodendrocyte precursor cells(OPCs).This interaction results in an upregulation of ubiquitin-specific peptidase 33(USP33)-mediated CNR1 deubiquitination,subsequently increasing CNR1 protein expression,activating the phosphorylation of the AKT/mTOR pathway,and promoting the differentiation of OPCs.In conclusion,our study suggests that 13-docosenamide can ameliorate chronic cerebral hypoperfusion-induced WMI and cognitive impairment by enhancing OPC differentiation and could serve as a potential therapeutic drug. 展开更多
关键词 13-Docosenamide White matter injury Oligodendrocyte precursor cell Cannabinoid receptor 1 Ubiquitin-specifc peptidase 33
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Research advances and future perspectives of zinc-based biomaterials for additive manufacturing
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作者 Kun-Shan Yuan Cheng-Chen Deng +10 位作者 Xiang-Xiu Wang Yue-Chuan Li chao zhou Chuan-Rong Zhao Xiao-Zhen Dai Ahsan-Riaz Khan Ze Zhang Robert Guidoin Hai-Jun Zhang Yu-Feng Zheng Gui-Xue Wang 《Rare Metals》 2025年第7期4376-4410,共35页
Additive manufacturing (AM) of zinc-based biodegradable materials is a hot research topic,especially for bone-scaffold applications,because of the moderate degradation rate,good biocompatibility,and suitable mechanica... Additive manufacturing (AM) of zinc-based biodegradable materials is a hot research topic,especially for bone-scaffold applications,because of the moderate degradation rate,good biocompatibility,and suitable mechanical properties of these materials.Furthermore,AM enables the fabrication of complex internal structures suitable for implants.Literature on the AM of degradable zinc-based biomaterials from the Web of Science Core Collection was evaluated in this review.The bibliometric tool CiteSpace was used to analyze historical characteristics,evolving research topics,and emerging trends in this field.Our research results predict that the composition,processing techniques,in vitro biocompatibility,and manufacturing quality of biodegradable AM zinc-basedmaterials will continue to be hot topics in recent years.To address implant requirements,particularly for bone-repair materials,the mechanical properties of materials (including the resistance to degradation,creep,and aging),degradation rates,in-vivo biocompatibility,and specialized processing techniques that affect these properties (such as coating processes,heat treatments,material surface structures,and micros truc tural compositions) will become hot research topics in the future.We propose future research directions based on an in-depth analysis of four main topics of AM biodegradable zinc-based materials (manufacturing quality,material composition,unit configuration,and biocompatibility).The findings provide important guidance for future theoretical research and industrial development of AM zinc-based biomaterials. 展开更多
关键词 Zinc-based biomaterials Additive manufacturing Mechanical properties Corrosion BIOCOMPATIBILITY
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Predicting mortality risk of severe fever with thrombocytopenia syndrome:A multi-center retrospective cohort study
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作者 Xue-Geng Hong Hong-Han Ge +11 位作者 Ning Cui Yan-Li Xu Xin Yang Jia-Hao Chen Xiao-Hong Yin Yi-Mei Yuan chao zhou Hao Li Xiao-Ai Zhang Ming Yue Ling Lin Wei Liu 《Virologica Sinica》 2025年第6期1011-1020,共10页
Severe fever with thrombocytopenia syndrome(SFTS)is an emerging tick-borne disease with high mortality,and clinical practice lacks dynamic tools to assess its rapidly evolving course.This study aims to develop stage-s... Severe fever with thrombocytopenia syndrome(SFTS)is an emerging tick-borne disease with high mortality,and clinical practice lacks dynamic tools to assess its rapidly evolving course.This study aims to develop stage-specific machine learning models to predict mortality risk using longitudinal biomarker data.We conducted a retrospective analysis of 5359 laboratory-confirmed SFTS patients from two hospitals in the highly endemic region in China.Serial measurements of 46 clinical and laboratory variables were integrated into a three-stage prognostic model developed using extreme gradient boosting(XGBoost).Within each clinical stage,key predictors and their relative contribution(RC)of mortality risk were assessed.Model performance was assessed based on discrimination,calibration,and decision curve analysis(DCA)in internal and external test sets.XGBoost models were constructed across 10 temporal phases,later consolidated into three clinically distinct stages via hierarchical clustering:early(≤7 days),intermediate(days 8-9),and late(≥10 days).Key predictors included age(dominant in early phase;RC,18.44%),lactate dehydrogenase(LDH;RC peaking at 60.10% in late phase),and monocyte percentage(RC range from 5.25% to 16.04%).Pathophysio-logical shifts across clinical stages were revealed:early viral cytopathy(dominated by age and MONO%),intermediate immunopathology(marked by LDH surge),and late hepatic failure(dominated by LDH,AST,and TBA).The model showed strong discrimination(Area under the receiver operating characteristic curve,AUCs:0.84-0.98 internal;0.91-0.98 external),calibration(Brier scores:0.04-0.11),and clinical utility via DCA.This study introduces a dynamic staging system that lever-ages predictive models and real-time patient data to monitor mortality risk and personalize SFTS care,which enables timely interventions to reduce deaths. 展开更多
关键词 Severe fever with thrombocytopenia syndrome(SFTS) Machine learning Clinical stage Fatal outcome Prediction model
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Mechanism of rock burst vertical damage induced by layered crack structures of the steeply inclined extremely thick coal seams
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作者 Taoping Zhong Zhenlei Li +6 位作者 Dazhao Song Majid Khan Xueqiu He Zemin Chen chao zhou Xudong Liu Panfei Feng 《International Journal of Coal Science & Technology》 2025年第2期123-144,共22页
This study focuses on steeply inclined and extremely thick coal seams(SIETCS)characterized by immense thickness,a steep inclination of coal seams(87°),and high horizontal stress.The geological conditions and mini... This study focuses on steeply inclined and extremely thick coal seams(SIETCS)characterized by immense thickness,a steep inclination of coal seams(87°),and high horizontal stress.The geological conditions and mining technology associated with SIETCS differ significantly from those of generally inclined coal seams,resulting in notable variations in roadway stress distributions.On SIETCS have predominantly examined the impact of rock layers flanking coal seams on rock bursts,with limited emphasis on SIETCS roadways.This study employs comprehensive methods,integrating numerical simulations,theoretical analyses,and field detections to investigate the stress distribution of SIETCS and the mechanisms of rock burst-induced vertical damage,subsequently validated in situ.The vertical stress in SIETCS is minimal,while horizontal stress is concentrated,leading to the formation of layered crack structures(LCS)that distribute above and below the roadways.Additionally,elastic energy significantly concentrates within the LCS.Axial dynamic compressive stress and vertical dynamic tensile stress along the LCS diminish its stability,readily triggering failure.During the LCS failure process,the stored energy is released,converting into kinetic energy required for coal body ejection after reaching the minimum energy for failure and dissipative energy,ultimately leading to rock burst-induced vertical damage in roadways.On-site detection and analysis within SIETCS,along with historical rock burst data,confirm the existence of LCS and its role in inducing vertical rock burst damage.This research establishes essential foundations for preventing rock bursts within SIETCS. 展开更多
关键词 Steeply inclined and extremely thick coal seams Rock burst Layered crack structures Dynamic stress Energy release
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Application of principal stress differentials to rockburst risk analysis and prevention
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作者 Taoping Zhong Zhenlei Li +5 位作者 Dazhao Song Xueqiu He Jianqiang Chen chao zhou Wei Yang Rongjie Fan 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3676-3690,共15页
The principal stresses will increase or decrease during mining,leading to variations in surrounding rock strength and subsequently an influence on the risk of rockbursts.To address this issue,this study conducted theo... The principal stresses will increase or decrease during mining,leading to variations in surrounding rock strength and subsequently an influence on the risk of rockbursts.To address this issue,this study conducted theoretical analysis,numerical simulation,and field monitoring.A rockburst risk analysis method that integrates dynamic changes in the stress and strength of surrounding rock was proposed and verified in the field.The dynamic changes in maximum(σ_(1))and minimum(σ_(3))principal stresses are represented by the σ_(1) and σ_(3) differentials,respectively.The difference in principal stress differential(DPSD),defined as the difference between σ_(1) and σ_(3),was introduced as a novel indicator for rockburst risk analysis.The findings of this study demonstrate a positive correlation between increases in DPSD and heightened risks of rockbursts,as evidenced by an increase in both the frequency of rockbursts and the occurrence of large-energy microseismic events.Conversely,a decrease in DPSD is associated with a reduction in risk.Specifically,in the W1123 panel of a coal mine susceptible to rockbursts,areas exhibiting higher DPSD values experienced more frequent and severe rockbursts.The DPSD-based analysis aligned well with the observed rockburst occurrences.Subsequent optimization of rockburst prevention measures in areas with elevated DPSD led to a reduction in DPSD.Following these adjustments,the W1123 panel predominantly experienced low-energy microseismic events,with a significant decrease in large-energy microseismic events and no further rockbursts.The DPSD analysis is a valuable tool for evaluating rockburst risk and aiding in prevention,which is of great significance for disaster prevention. 展开更多
关键词 ROCKBURST Principal stress Principal stress differential Rockburst risk analysis Microseismic event
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Magnetism-structure triple point morphotropic phase boundary and resulting W-type magnetostrictive effect in Ni_(50)Mn_(34)Sb_(16-x)Ga_(x) Heusler alloys
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作者 Qi-Zhong Zhao Fang-Hua Tian +8 位作者 Sen Kong Jia-Le Guo Zhi-Yong Dai Tie-Yan Chang chao zhou Yin Zhang Kai-Yan Cao Sen Yang Xiao-Ping Song 《Rare Metals》 2025年第3期1905-1916,共12页
The mutual coupling of structure and magnetism is crucial for Heusler alloys.In this paper,Ni_(50)Mn_(34)Sb_(16-x)Ga_(x)(0≤x≤16)alloys were prepared by arc melting.Based on the test results of structure and magnetis... The mutual coupling of structure and magnetism is crucial for Heusler alloys.In this paper,Ni_(50)Mn_(34)Sb_(16-x)Ga_(x)(0≤x≤16)alloys were prepared by arc melting.Based on the test results of structure and magnetism,the magnetic-structural phase diagram of Ni_(50)Mn_(34)Sb_(16-x)Ga_(x)(0≤x≤16)was drawn.The structure changes from cubic to monoclinic and finally to tetragonal as the x increases at room temperature.Its phase diagram shows a morphotropic phase boundary(MPB)starting from a tricritical triple point(around the Ni_(50)Mn_(34)Sb_(5)Ga_(11)alloy)of a cubic paramagnetic phase,ferromagnetic monoclinic,and antiferromagnetic tetragonal phases.And Ni_(50)Mn_(34)Sb_(5)Ga_(11)alloy has experienced five different phase states:paramagnetic austenite→ferromagnetic austenite→antiferromagnetic martensite→ferromagnetic martensite→spin glass as the temperature decreased.Further study of the alloys’magnetostrictive properties near the MPB showed that as x increases,a negative strain initially appears,followed by a W-type that crosses negative and positive strains,and then a positive strain.This is caused by the inconsistency in the speed and degree of magnetic domain walls response with monoclinic and tetragonal coexisting structures.This indicates that coupling between structure and magnetism is critical to the properties of materials.This work provides valuable insights into the magnetostrictive behavior and structural evolution of Heusler alloys,particularly in the context of MPB systems,and offers guidance for the design and optimization of material properties through controlled magnetic-structural interactions.Kindly check and confirm the edit made in the title.The edit made in the title has been confirmed to be accurate. 展开更多
关键词 Ferromagnetic shape memory alloy Heusler alloys MAGNETOSTRICTION Martensite transformation Triple point morphotropic phase boundary
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某高校医学硕士研究生心理健康问题现状及对策研究 被引量:15
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作者 周超 张铮 +2 位作者 孙聪聪 崔明湖 张英姿 《中国高等医学教育》 2022年第2期132-134,共3页
目的:分析“医教协同”背景下医学硕士研究生心理健康问题现状,探讨开展医学生心理健康教育的对策。方法:选取某高校医学硕士研究生作为研究对象,进行问卷调查及统计分析,对影响因素进行调查分析,并制定相应的对策。结果:(1)医学硕士研... 目的:分析“医教协同”背景下医学硕士研究生心理健康问题现状,探讨开展医学生心理健康教育的对策。方法:选取某高校医学硕士研究生作为研究对象,进行问卷调查及统计分析,对影响因素进行调查分析,并制定相应的对策。结果:(1)医学硕士研究生存在心理健康问题最高和最低的因子分别是强迫症状和恐怖,检出率分别为9.06%、1.29%。(2)不同年级的医学硕士研究生均存在抑郁、焦虑等心理健康问题,其中2014级焦虑发生率最高(1.75%),2013级抑郁发生率最高(17.95%);心理健康问题最为严重的是2013级,检出率为10.20%。(3)医学硕士研究生SCL-90各个因子评分均低于常模组,差异具有统计学意义(P<0.001)。结论:医学硕士研究生面临着不同心理健康问题,只有社会、学校、导师等各方面给予支持和关爱,才能为其提供良好的成长环境。 展开更多
关键词 医教协同 医学院校 硕士 研究生 心理健康 医学教育
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Insights to unusual antiferromagnetic behavior and exchange coupling interactions in Mn_(23)C_(6)
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作者 Ze-Kun Yu chao zhou +8 位作者 Kuo Bao Zhao-Qing Wang En-Xuan Li Jin-Ming Zhu Yuan Qin Yu-Han Meng Pin-Wen Zhu Qiang Tao Tian Cui 《Chinese Physics B》 2025年第3期152-159,共8页
We report the structural,mechanical and electromagnetic properties of the intermetallic compound Mn_(23)C_(6).The bulk Mn_(23)C_(6)sample was synthesized using high temperature high pressure quenching method(HTHPQM),a... We report the structural,mechanical and electromagnetic properties of the intermetallic compound Mn_(23)C_(6).The bulk Mn_(23)C_(6)sample was synthesized using high temperature high pressure quenching method(HTHPQM),and investigated in detail by x-ray diffraction,electron microscope,magnetization and electrical resistivity measurements,etc.First-principles calculation based on density functional theory ab intio simulation was carried out to calculate the bonding and electromagnetic properties of Mn_(23)C_(6).Based on our experimental and simulated results,the Mn_(23)C_(6)in this work is single phase of a faced-centered cubic structure with space group Fm-3m(No.225).Determined by SEM and TEM,the bulk sample consists of monocrystal Mn_(23)C_(6)crystals with 2-15μm grain sizes,it is the quick quenching method in the synthesizing process that brings such small crystal grain size.Archimedes method gives its density of 7.14 g/cm^(3),95.74%of its theoretically calculated density 7.458 g/cm^(3).Owing to the abundant Mn 3d electrons and a framework of strongly linked Mn atoms in Mn_(23)C_(6),the electrical conductivity is up to 8.47×10^(-4)Ω·m,which shows that Mn_(23)C_(6)is a good conductor.Our magnetic susceptibility analyses reveal a magnetization peak in the M-T curve at 104 K,combined with the M-H curve and Curie-Weiss law,this peak usually means the transformation between paramagnetic and antiferromagnetic orders.To gain an insight into the mechanism of the magnetic phase transition,we calculated the magnetic properties,and the results show that different from normal antiferromagnetic order,the magnetic orders in Mn_(23)C_(6)consist of three parts,the direct ferromagnetic and antiferromagnetic exchange coupling interactions between Mn atoms,and the indirect antiferromagnetic super-exchange interaction between Mn and C atoms.Therefore,we reveal that the Mn_(23)C_(6)is a complex magnetic competition system including different magnetic orders and interactions,instead of the normal long-range antiferromagnetic order. 展开更多
关键词 intermetallic compound(IMC) MAGNETISM high temperature high pressure(HTHP) density functional theory(DFT)
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A Novel Low-Damage Viscoelastic-Surfactant Foam Fracturing Fluid for Tight Reservoirs: Development and Performance Assessment
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作者 Yu Li Jie Bian +5 位作者 Liang Zhang Xuesong Feng Jiachen Hu Ji Yu chao zhou Tian Lan 《Fluid Dynamics & Materials Processing》 2025年第10期2539-2556,共18页
As oil and gas development increasingly targets unconventional reservoirs,the limitations of conventional hydraulic fracturing,namely high water consumption and significant reservoir damage,have become more pronounced... As oil and gas development increasingly targets unconventional reservoirs,the limitations of conventional hydraulic fracturing,namely high water consumption and significant reservoir damage,have become more pronounced.This has driven growing interest in the development of clean fracturing fluids that minimize both water usage and formation impairment.In this study,a low-liquid-content viscoelastic surfactant(VES)foam fracturing fluid system was formulated and evaluated through laboratory experiments.The optimized formulation comprises 0.2%foaming agent CTAB(cetyltrimethylammonium bromide)and 2%foam stabilizer EAPB(erucamidopropyl betaine).Laboratory tests demonstrated that the VES foam system achieved a composite foam value of 56,700 mL・s,reflecting excellent foaming performance.Proppant transport experiments revealed minimal variation in suspended sand volume over 120 min across different sand ratios,indicating robust sand-carrying capacity even at high proppant concentrations.Rheological measurements showed that the fluid maintained a viscosity above 120 mPa・s after 120 min of shearing at 70℃ and a shear rate of 170 s−1,with the elastic modulus exceeding the viscous modulus,confirming the system’s exceptional stability and resilience.Furthermore,core damage tests indicated that the VES foam caused only 4.42%formation damage,highlighting its potential for efficient and low-damage stimulation of tight reservoirs.Overall,the findings demonstrate that this low-liquid-content VES foam provides a highly effective,environmentally considerate alternative for hydraulic fracturing in unconventional formations,combining superior proppant transport,rheological stability,and minimal reservoir impairment. 展开更多
关键词 Foam fracturing fluid viscoelastic surfactant reservoir stimulation performance evaluation
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The B-type response regulator ZmRR5 controls maize kernel size by regulating BETL development
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作者 Menglin Pu Bohui Wang +11 位作者 chao zhou Youqiang Li Mingfei Sun Guangming Zheng Yuejia Zhang Jiawen Wu Jun Li Xiaofei He Zhiming Zhang Haiping Ding Xiansheng Zhang Xiangyu Zhao 《The Crop Journal》 2025年第3期792-804,共13页
Maize(Zea mays L.)is one of the world's most important staple crops,and is used for manufacturing food,feed,and industrial products.A key factor in maize yield is the grain weight,which directly influences product... Maize(Zea mays L.)is one of the world's most important staple crops,and is used for manufacturing food,feed,and industrial products.A key factor in maize yield is the grain weight,which directly influences productivity.In this study,we revealed the role of smk23 in maize kernel development.The ethyl methanesulfonate mutant smk23 is characterized by substantially reduced kernel weight.Through map-based cloning,smk23 was found to be located on Chr5 and encode a putative B-type response regulator,Zm RR5.A change from G to A occurs in the coding sequence of Zm RR5,resulting in the early termination of smk23.In Arabidopsis,B-type response regulators are involved in cytokinin signaling.Histological analysis and in situ hybridization of the mutant revealed abnormal endosperm development,particularly in the basal endosperm transfer layer(BETL),a specialized tissue critical for nutrient transport from the maternal tissues to the developing kernel.Zm RR5 positively regulates key genes involved in BETL development and function,including MRP1 and TCRR1.Furthermore,RNA sequencing revealed that several genes closely linked to BETL development,including BETL2,MEG1,and MN1,were significantly downregulated in smk23.These genes are essential for nutrient transport,tissue development and signal transduction.In addition,haploid analysis of Zm RR5 revealed natural variations(Hap 2)that may contribute to the increased kernel yield.Disruption of Zm RR5 function in smk23 leads to defects in BETL development,impairing its ability to transport nutrients,and ultimately resulting in a smaller kernel size.This study provides new insights into the molecular mechanisms through which Zm RR5 regulates maize kernel development and offers potential strategies for improving grain yield. 展开更多
关键词 Maize yield Cytokinin B-type response regulator ENDOSPERM BETL
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基于近红外机器视觉的鱼类摄食强度评估方法研究 被引量:15
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作者 周超 徐大明 +4 位作者 吝凯 陈澜 张松 孙传恒 杨信廷 《智慧农业》 2019年第1期76-84,共9页
在水产养殖中,鱼类的摄食强度可以反映其食欲,准确客观地评估鱼类的摄食强度对指导投喂和生产实践具有重要意义。针对当前鱼类摄食强度评估过程中存在的人工观测效率低、客观性不强的问题,本研究以实现鱼类食欲的自动客观分析为目的,提... 在水产养殖中,鱼类的摄食强度可以反映其食欲,准确客观地评估鱼类的摄食强度对指导投喂和生产实践具有重要意义。针对当前鱼类摄食强度评估过程中存在的人工观测效率低、客观性不强的问题,本研究以实现鱼类食欲的自动客观分析为目的,提出了一种基于近红外机器视觉的游泳型鱼类摄食强度的评估方法。首先,利用近红外工业相机搭建了近红外图像采集系统,采集了鱼类摄食过程中的图像。经过一系列图像处理步骤后,利用灰度共生矩阵提取摄食图像的纹理特征变量信息,包括对比度、能量、相关性、逆差距和熵等。之后,将这5个特征变量作为输入向量构建了模型的数据集,并训练了支持向量机分类器。为了提高模型分类的准确率,利用网格搜索法选取支持向量机分类器的最优惩罚系数c和核函数参数g。最后利用训练好的模型将鱼类的摄食强度分为弱、一般、中和强4类,最终实现了鱼类摄食强度的评估。试验结果表明,图像纹理可以较好地描述鱼类摄食过程中的行为变化,正确识别4类摄食强度的准确率达到87.78%,且不需要考虑水花等对成像质量的影响,具有较强的适应性。本方法可用于鱼类食欲的自动客观评估,为后续投喂决策提供理论依据和方法支持。 展开更多
关键词 水产养殖 近红外机器视觉 鱼类摄食强度评估 支持向量机 投喂决策
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