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Enhanced magnetic properties in a Fe-based amorphous alloy via ultrasonic vibration rapid processing 被引量:1
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作者 Hong-Zhen Li Sajad Sohrabi +4 位作者 Xin Li Lu-Yao Li Jiang Ma Huan-Lin Peng Chao Yang 《Rare Metals》 2025年第4期2853-2860,共8页
In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment techni... In general,the rapid growth of α-Fe clusters is a challenge in high Fe-content Fe-based amorphous alloys,negatively affecting their physical properties.Herein,we introduce an efficient and rapid post-treatment technique known as ultrasonic vibration rapid processing(UVRP),which enables the formation of high-density strong magnetic α-Fe clusters,thereby enhancing the soft magnetic properties of Fe_(78)Si(13)B_(9) amorphous alloy ribbon. 展开更多
关键词 enhancing soft magnetic properties soft magnetic properties physical propertieshereinwe Fe based amorphous alloy amorphous alloy ribbon ultrasonic vibration rapid processing uvrp which Fe clusters ultrasonic vibration rapid processing
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Status and Development of Rapid Detection Technology for Tunnel Structural Defects 被引量:3
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作者 LIU Xuezeng FANG Maoliu +3 位作者 WU Dexing LI Yinping LIU Xingen LI Gang 《隧道建设(中英文)》 北大核心 2025年第4期657-676,I0005-I0024,共40页
Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,an... Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection. 展开更多
关键词 TUNNEL structural defect inspection techniques inspection equipment rapid inspection
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Rapid软件CTP参数对缺血性脑卒中患者侧支循环及临床预后的评估价值
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作者 叶杨 陈飞 +3 位作者 辛立旭 董从松 姚立正 王澍 《中国CT和MRI杂志》 2025年第7期28-31,共4页
目的分析Rapid软件CT灌注(CTP)参数对急性缺血性脑卒中(AIS)患者侧支循环及临床预后的评估价值。方法选择本院2021年1月至2023年6月收治的AIS患者174例,所有患者均接受一站式CT检查,包CT平扫、CTP、CT血管成像(CTA),以多时相CTA结果进... 目的分析Rapid软件CT灌注(CTP)参数对急性缺血性脑卒中(AIS)患者侧支循环及临床预后的评估价值。方法选择本院2021年1月至2023年6月收治的AIS患者174例,所有患者均接受一站式CT检查,包CT平扫、CTP、CT血管成像(CTA),以多时相CTA结果进行侧支循环判定,随访3个月以改良Rankin量表进行预后判断,比较不同侧支循环和预后患者的Rapid软件CTP参数[达峰时间(Tmax)>6 s体积、Tmax>8 s体积、Tmax>10 s体积、脑血流量(CBF)<30%体积、缺血半暗带体积、不匹配比率(MMR)、脑血容量(CBV)指数、低灌注(HIR)指数];采用受试者工作特征(ROC)曲线分析CTP参数预测AIS预后的价值。结果与侧支循环好组相比,侧支循环差组Tmax>6 s体积、Tmax>8 s体积、Tmax>10 s体积、CBF<30%体积及HIR指数均较高,MMR、CBV指数较低(P<0.05)。与预后良好组相比,预后不良组Tmax>6 s体积、Tmax>8 s体积、Tmax>10 s体积、CBF<30%体积及HIR指数均较高,MMR、CBV指数较低(P<0.05)。与预后良好组相比,预后不良组年龄、基线NIHSS评分、入院24 h NIHSS评分、住院时间、空腹血糖及心房颤动占比均较高(P<0.05)。多因素Logistic回归分析显示,术后24 h HINSS评分、CBF<30%体积、HIR指数升高均是AIS患者预后不良的独立危险因素(OR>1,P<0.05),CBV指数升高是预后良好的保护因素(0<OR<1,P<0.05)。ROC曲线分析显示,CBF<30%体积、CBV指数、HIR指数及三者联合预测AIS患者预后不良的AUC(95%CI)分别为0.778(0.703~0.842)、0.801(0.730~0.862)、0.770(0.695~0.835)、0.885(0.822~0.931),联合预测效能高于单独应用(P<0.05)。结论Rapid软件CTP参数可有效评估AIS患者侧支循环状态,且CBF<30%体积、HIR指数、CBV指数联合检测可作为AIS患者预后判断的重要参考指标。 展开更多
关键词 rapid软件 CT灌注 急性缺血性脑卒中 侧支循环 临床预后 预测
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Beneficial role of Sn in rapid rust stabilization of weathering steel in marine environments 被引量:1
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作者 Liu Yang Xuequn Cheng Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 2025年第5期1141-1150,共10页
Weathering steel exhibits excellent corrosion resistance and is widely used in bridges,towers,railways,highways,and other engineering projects that are exposed to the atmosphere for long periods of time.However,before... Weathering steel exhibits excellent corrosion resistance and is widely used in bridges,towers,railways,highways,and other engineering projects that are exposed to the atmosphere for long periods of time.However,before the formation of stable rust layers,weathering steel is prone to liquid rust sagging and spattering,leading to environmental pollution and city appearance concerns.These factors limit the application and development of weathering steel.In this study,a rapid and environmentally friendly method was de-veloped by introducing alloying elements,specifically investigating the role of Sn in the rapid stabilization of rust layers in marine atmo-spheric environments.The rust layer formed on weathering low-alloy steel exposed to prolonged outdoor conditions and laboratory im-mersion experiments was explored using electron probe micro-analyzer(EPMA),micro-Raman,X-ray photoelectron spectroscopy(XPS),and electrochemical measurements.Results showed an optimal synergistic effect between Sn and Cr,which facilitated the accelerated densification of the rust layer.This beneficial effect enhanced the capability of the rust layer to resist Cl^(-)erosion and improved the protec-tion performance of the rust layer. 展开更多
关键词 marine atmosphere rapid stabilization weathering steel SN
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Rapid screening of inorganic arsenic in groundwater on-site by a portable three-channel colorimeter 被引量:1
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作者 Xiaobao Tuo Yanhua Duan +5 位作者 Guanting Lin Tianci Jiang Wenhui Liu Fangyi Chen Xianjun Xie Yan Zheng 《Journal of Environmental Sciences》 2025年第7期158-171,共14页
Rapid screening of inorganic arsenic(iAs)in groundwater used for drinking by hundreds of millions of mostly rural residents worldwide is crucial for health protection.Most commercial field test kits are based on the G... Rapid screening of inorganic arsenic(iAs)in groundwater used for drinking by hundreds of millions of mostly rural residents worldwide is crucial for health protection.Most commercial field test kits are based on the Gutzeit reaction that uses mercury-based reagents for color development,an environmental concern that increasingly limits its utilization.This study further improves the Molybdenum Blue(MB)colorimetric method to allow for faster screening with more stable reagents.More importantly,a portable three-channel colorimeter is developed for screening iAs relative to the WHO drinking water guideline value(10μg/L).Adding the reducing reagents in sequence not only prolongs the storage time to>7 days,but also accelerates the color development time to 6 min in conjunction with lowering the H_(2)SO_(4) concentration in chromogenic reagents.The optimal pH ranges from 1.2 to 1.3 and is achieved by acidifying groundwater to 1%(V/V)HCl.With detection limits of 3.7μg/L for inorganic arsenate(iAs(V))and 3.8μg/L for inorganic arsenite(iAs(Ⅲ)),testing groundwater with-10μg/L of As has a precision<20%.The method works well for a range of phosphate concentrations of 48-950μg/L(0.5-10μmol/L).Concentrations of total_iAs(6-300μg/L),iAs(V)(6-230μg/L)and iAs(Ⅲ)(0-170μg/L)for 14 groundwater samples from Yinchuan Plain,Pearl River Delta,and Jianghan Plain,are in excellent agreements(linear regression slope:0.969-1.029)with the benchmark methods.The improved chemistry here lays the foundation for the MB colorimetric method to become a commercially viable screening tool,with further engineering and design improvement of the colorimeter. 展开更多
关键词 Groundwater arsenic rapid screening On-site detection Molybdenum blue Three-channel spectrophotometer
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The predictive value of NLR and SII in anti⁃MDA5 antibody⁃positive dermatomyositis with rapidly progressive interstitial lung disease
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作者 CAI Qingqing YOU Hanxiao +7 位作者 WANG Lei LÜChengyin SHI Yumeng QIU Yulu WU Lingyun WANG Fang ZHANG Miaojia TAN Wenfeng 《南京医科大学学报(自然科学版)》 北大核心 2025年第2期196-207,共12页
Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(... Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(anti⁃MDA5+)dermatomyositis(DM)develop into the rapidly progressive interstitial lung disease(RPILD).Methods:We retrospectively analyzed the clinical and laboratory data of 124 anti⁃MDA5+DM patients from the First Affiliated Hospital of Nanjing Medical University between March 2019 and September 2023.We identified independent risk factors associated with the development and mortality of RPILD with the Cox regression analysis,and determined the optimal cut⁃off values for predicting adverse outcomes with the receiver operating characteristic(ROC)curve analysis.Results:Among the 124 patients,36 patients(29.03%)developed RPILD,and 39 patients(31.45%)died during the follow⁃up period.The results of multivariate Cox regression analysis showed that the elevated NLR was an independent risk factor for RPILD development,while the elevated SII expression was independently associated with the increased mortality of RPILD.Based on the ROC curve analysis,NLR>6.12 was a predictor for RPILD,and SII>875.79 was associated with increased mortality risk of RPILD.Conclusion:Both NLR and SII are accessible,cost⁃effective,and reliable prognostic indicators for the prognosis of patients with anti⁃MDA5^(+)DM,providing a valuable guidance for clinical management and risk stratification of the disease. 展开更多
关键词 anti⁃melanoma differentiation⁃associated gene 5⁃positive dermatomyositis neutrophil⁃to⁃lymphocyte ratio rapidly pro⁃gressive interstitial lung disease systemic immune⁃inflammation index
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Rapid Identification of Cryptococcus Organisms Easily Possible with Stimulated Raman Histology on a Pulmonary Tiny Biopsy Specimen: A Case Report
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作者 Howard D. Epstein Cory D. Sessum +2 位作者 Christian Freudiger Steven Pastore Javier A. Longoria 《Case Reports in Clinical Medicine》 2025年第2期80-85,共6页
Background: Cryptococcus neoformans is an opportunistic fungal pathogen that primarily affects immunocompromised individuals. While traditional histologic methods such as hematoxylin and eosin (H&E) staining can s... Background: Cryptococcus neoformans is an opportunistic fungal pathogen that primarily affects immunocompromised individuals. While traditional histologic methods such as hematoxylin and eosin (H&E) staining can sometimes identify fungal organisms, definitive diagnosis typically requires microbiological culture or molecular testing. Stimulated Raman Histology (SRH) is an emerging imaging technology that enables rapid, label-free tissue analysis, potentially improving intraoperative diagnostic workflows. Aim: This case report explores the utility of SRH for the real-time identification of pulmonary cryptococcosis, highlighting its potential to enhance tissue triage and expedite diagnosis. Case Presentation: We report a 44-year-old man with a history of smoking and alcohol use who presented with a right lower lung mass. An ION robotic-assisted bronchoscopy was performed, and SRH was used intraoperatively for real-time tissue evaluation. Within approximately 90 seconds, SRH provided morphologic findings indicative of Cryptococcus neoformans, prompting additional microbiological testing, which confirmed the diagnosis. The patient required a six-week hospitalization with antifungal therapy. Conclusion: This case demonstrates the potential of SRH as a rapid, intraoperative diagnostic tool for detecting fungal infections in pulmonary specimens. By enabling real-time morphological assessment, SRH can optimize biopsy specimen triage, reduce the need for repeat procedures, and improve patient management. Integrating SRH into diagnostic workflows may be particularly beneficial in resource-limited settings, where timely cryptococcosis diagnosis is critical. 展开更多
关键词 rapid OnSite Assessment (ROSE) FNA CRYPTOCOCCUS Fungal Infection Diagnosis SRH HISTOLOGY
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定量脑电图与RAPID灌注参数在急性缺血性卒中取栓预后不良的研究进展
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作者 刘小芳(综述) 陈胜利(审校) 《中风与神经疾病杂志》 2025年第6期563-567,共5页
急性大血管闭塞性缺血性脑卒中具有较高的致残率及致死率,给社会经济和医疗卫生体系造成极大负担,机械取栓已经成为其标准治疗方式,但血管成功开通后仍有部分患者预后不良,因此探索能够判断患者不良预后的因素至关重要。定量脑电图可以... 急性大血管闭塞性缺血性脑卒中具有较高的致残率及致死率,给社会经济和医疗卫生体系造成极大负担,机械取栓已经成为其标准治疗方式,但血管成功开通后仍有部分患者预后不良,因此探索能够判断患者不良预后的因素至关重要。定量脑电图可以量化、客观评估患者脑功能的变化过程,基于脑CTP的RAPID灌注参数可以快速量化脑组织局部血流灌注情况。这种灌注神经成像和电生理活动相关结合方式可以量化脑梗死相关的缺血严重程度和神经元功能损害,因此本文对两者在卒中预后评估中的应用价值进行综述。 展开更多
关键词 急性缺血性卒中 机械取栓 定量脑电图 rapid灌注参数
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Evaluation of a Rapid Chromogenic Medium for the Quantitative Detection of Bacillus cereus
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作者 Xiaoli WU Shuhuan ZHAO +4 位作者 Yunxia WANG Hongbing JIA Xue HU Yuelian NING Zhiyong LYU 《Asian Agricultural Research》 2025年第11期48-50,53,共4页
[Objectives]To evaluate the performance of two rapid chromogenic media for the detection of Bacillus cereus in milk powder,and verify the media's inclusivity,exclusivity,and accuracy,and to assess their applicabil... [Objectives]To evaluate the performance of two rapid chromogenic media for the detection of Bacillus cereus in milk powder,and verify the media's inclusivity,exclusivity,and accuracy,and to assess their applicability for the quantitative detection of B.cereus.[Methods]B.cereus in milk powder samples was quantified using two rapid chromogenic media in combination with the national standard method.Agreement between the quantitative results from the three methods was subsequently assessed for agreement via a paired t-test.[Results]No significant differences were observed between the bacterial counts yielded by the two rapid chromogenic media and the national standard method(P>0.05),with excellent agreement between them.[Conclusions]The method of rapid chromogenic culture medium is rapid and simple. 展开更多
关键词 Bacillus CEREUS rapid CHROMOGENIC culture MEDIUM COUNTING
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Research on the rapid diagnosis method for hunting of high-speed trains
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作者 Wanru Xie Yixin Zhao +3 位作者 Gang Zhao Fei Yang Zilong Wei Jinzhao Liu 《Railway Sciences》 2025年第1期1-21,共21页
Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyz... Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyze the data characteristics of continuous hunting of high-speed trains passing through turnouts and propose a diagnostic method for engineering applications.Design/methodology/approach–First,Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)is performed to determine the first characteristic component of the car body’s lateral acceleration.Then,the Short-Time Fourier Transform(STFT)is performed to calculate the marginal spectra.Finally,the presence of a continuous hunting problem is determined based on the results of the comparison calculations and diagnostic thresholds.To improve computational efficiency,permutation entropy(PE)is used as a fast indicator to identify turnouts with potential problems.Findings–Under continuous hunting conditions,the PE is less than 0.90;the ratio of the maximum peak value of the signal component to the original signal peak value exceeded 0.7,and there is an energy band in the STFT time-frequency map,which corresponds to a frequency distribution range of 1–2 Hz.Originality/value–The research results have revealed the lateral vibration characteristics of the high-speed train’s car body during continuous hunting when passing through turnouts.On this basis,an effective diagnostic method has been proposed.With a focus on practical engineering applications,a rapid screening index for identifying potential issues has been proposed,significantly enhancing the efficiency of diagnostic processes. 展开更多
关键词 High-speed railway Periodic hunting rapid diagnosis CEEMDAN STFT Permutation entropy
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Subgenome asymmetry of gibberellins-related genes plays important roles in regulating rapid growth of bamboos
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作者 Ling Mao Cen Guo +9 位作者 Liang-Zhong Niu Yu-Jiao Wang Guihua Jin Yi-Zhou Yang Ke-Cheng Qian Yang Yang Xuemei Zhang Peng-Fei Ma De-Zhu Li Zhen-Hua Guo 《Plant Diversity》 2025年第1期68-81,共14页
Rapid growth is an innovative trait of woody bamboos that has been widely studied.However,the genetic basis and evolution of this trait are poorly understood.Taking advantage of genomic resources of 11 representative ... Rapid growth is an innovative trait of woody bamboos that has been widely studied.However,the genetic basis and evolution of this trait are poorly understood.Taking advantage of genomic resources of 11 representative bamboos at different ploidal levels,we integrated morphological,physiological,and transcriptomic datasets to investigate rapid growth.In particular,these bamboos include two large-sized and a small-sized woody species,compared with a diploid herbaceous species.Our results showed that gibberellin A1 was important for the rapid shoot growth of the world's largest bamboo,Dendrocalamus sinicus,and indicated that two gibberellins(GAs)-related genes,KAO and SLRL1,were key to the rapid shoot growth and culm size in woody bamboos.The expression of GAs-related genes exhibited significant subgenome asymmetry with subgenomes A and C demonstrating expression dominance in the large-sized woody bamboos while the generally submissive subgenomes B and D dominating in the small-sized species.The subgenome asymmetry was found to be correlated with the subgenome-specific gene structure,particularly UTRs and core promoters.Our study provides novel insights into the molecular mechanism and evolution of rapid shoot growth following allopolyploidization in woody bamboos,particularly via subgenome asymmetry.These findings are helpful for understanding of how polyploidization in general and subgenome asymmetry in particular contributed to the origin of innovative traits in plants. 展开更多
关键词 ALLOPOLYPLOIDS GAs DEGs Culm sizes rapid shoot growth Woody bamboos
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Understanding the initial conditions contributing to the rapid intensification of typhoons through ensemble sensitivity analysis
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作者 Yixuan Ren Lili Lei +2 位作者 Jian-Feng Gu Zhe-Min Tan Yi Zhang 《Atmospheric and Oceanic Science Letters》 2025年第2期36-42,共7页
While steady improvements have been achieved for the track forecasts of typhoons,there has been a lack of improvement for intensity forecasts.One challenge for intensity forecasts is to capture the rapid intensificati... While steady improvements have been achieved for the track forecasts of typhoons,there has been a lack of improvement for intensity forecasts.One challenge for intensity forecasts is to capture the rapid intensification(RI),whose nonlinear characteristics impose great difficulties for numerical models.The ensemble sensitivity analysis(ESA)method is used here to analyze the initial conditions that contribute to typhoon intensity forecasts,especially with RI.Six RI processes from five typhoons(Chaba,Haima,Meranti,Sarika,and Songda)in 2016,are applied with ESA,which also gives a composite initial condition that favors subsequent RI.Results from individual cases have generally similar patterns of ESA,but with different magnitudes,when various cumulus parameterization schemes are applied.To draw the initial conditions with statistical significance,sample-mean azimuthal components of ESA are obtained.Results of the composite sensitivity show that typhoons that experience RI in 24 h favor enhanced primary circulation from low to high levels,intensified secondary circulation with increased radial inflow at lower levels and increased radial outflow at upper levels,a prominent warm core at around 300 hPa,and increased humidity at low levels.As the forecast lead time increases,the patterns of ESA are retained,while the sensitivity magnitudes decay.Given the general and quantitative composite sensitivity along with associated uncertainties for different cumulus parameterization schemes,appropriate sampling of the composite sensitivity in numerical models could be beneficial to capturing the RI and improving the forecasting of typhoon intensity. 展开更多
关键词 TYPHOON rapid intensification Ensemble sensitivity analysis Composite sensitivity
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Rapid identification method for inclusions in evaluating high-purity quartz
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作者 Min Liu Guocheng Lv +7 位作者 Xin Liu Zijie Ren Meitang Liu Ritong Huang Xinyu Hou Qinwen Zheng Libing Liao Jingwen Mao 《International Journal of Minerals,Metallurgy and Materials》 2025年第9期2131-2140,共10页
The rapid growth of semiconductor,photovoltaic,and other emerging industries has led to a sharp increase in the demand for high-purity quartz in China,particularly 4N5-grade(99.995%pure SiO_(2)).However,heavy reliance... The rapid growth of semiconductor,photovoltaic,and other emerging industries has led to a sharp increase in the demand for high-purity quartz in China,particularly 4N5-grade(99.995%pure SiO_(2)).However,heavy reliance on imported high-purity quartz poses a significant risk to the security of key national strategic industries.To address this challenge,China is focusing on identifying domestic sources of high-purity quartz and developing efficient evaluation methods.This study investigates the inclusion content in three types of quartz:pegmatite,vein quartz,and white granite.A grading system based on the transmittance of quartz grains was established by analyz-ing the number of inclusions.Five quartz ore samples from different regions were purified,and the resulting concentrates were analyzed using inductively coupled plasma mass spectrometry(ICP-MS).The relationships among the inclusion content of raw quartz,impurity composition of purified quartz,and quality of sintered fused quartz products were examined.The findings demonstrate that quartz with fewer inclusions results in lower impurity levels after purification,higher SiO_(2)purity,and more translucent glass,as confirmed by firing tests.Herein,this study establishes a clear connection between quartz inclusions and the overall quality of high-purity quartz.The pro-posed approach enables the rapid assessment of quartz deposit quality by identifying inclusions,offering a practical and efficient method for locating high-quality quartz resources. 展开更多
关键词 high-purity quartz GRADING INCLUSIONS rapid evaluation PURIFICATION impurity content mineral exploration resource security
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Effect of rapid cold stamping on microstructure and mechanical properties of spray-formed Al-Zn-Mg-Cu alloy
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作者 Cai-he FAN Ji LI +4 位作者 Shuang-jun YANG Ze-yi HU Qin WU Ling OU Shuai WU 《Transactions of Nonferrous Metals Society of China》 2025年第9期2846-2858,共13页
X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS),electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM)were used to systematically investigate the ... X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS),electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM)were used to systematically investigate the impact of rapid cold stamping on microstructural evolution and mechanical properties of spray-formed Al-Zn-Mg-Cu alloys under ambient conditions.The results reveal that the dislocation density increases with successive cold stamping passes,the volume fraction of the secondary phase(Mg(Zn,Cu,Al)_(2))increases from 15.64% to 23.94%,and the average size decreases from 1.41 to 0.75μm.The pinning effect of the secondary phases on dislocations promotes a significant transformation from low-angle grain boundaries to high-angle grain boundaries,resulting in the average grain size decreasing from 5.75 to 0.97μm.The strength and hardness of the samples increase with successive cold stamping passes,which is attributed to the synergistic effects of dislocation strengthening,grain boundary strengthening,and secondary phase strengthening. 展开更多
关键词 Al-Zn-Mg-Cu alloy rapid cold stamping TEXTURE sub-grain boundaries secondary phase
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One-step synthesis of ThMn_(12)-type Sm_(0.8)Zr_(0.2)Fe_(11)SiB_(x)(x=0-0.2)ribbon magnets via rapid solidification
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作者 Chi Zhang Hui-Dong Qian +3 位作者 Wenyun Yang Jingzhi Han Xuegang Chen Jinbo Yang 《Chinese Physics B》 2025年第7期566-571,共6页
ThMn_(12)-type iron-rich rare-earth permanent magnetic materials have garnered significant attention due to their exceptional intrinsic magnetic properties.However,challenges such as the metastable nature of the ThMn1... ThMn_(12)-type iron-rich rare-earth permanent magnetic materials have garnered significant attention due to their exceptional intrinsic magnetic properties.However,challenges such as the metastable nature of the ThMn12-type phase,excessively small single-domain grain size,and complex fabrication processes have hindered the achievement of high phase purity,uniform microstructure,and desirable extrinsic performance.In this study,we directly synthesized ThMn_(12)-type Sm_(0.8)Zr_(0.2)Fe_(11)SiB_(x)(x=0-0.2)ribbon magnets via boron doping combined with a one-step rapid solidification method.This approach not only simplifies the fabrication process but also enhances phase stability and achieves a uniform microstructure with high ThMn12-type phase purity.By optimizing the boron content and cooling rate,the resulting magnets exhibit a coercivity(H_(c))of 6222 Oe,a remanence(M_(r))of 80 emu/g,and a remanence ratio(M_(r)/M_(s))of 0.71.This work demonstrates a streamlined approach to producing high-performance ThMn12-type magnets and provides insights into their practical application potential. 展开更多
关键词 ThMn12-type permanent magnet rapid solidification phase stabilization microstructure
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Microstructural Evolution of Rapidly Solidified Ni-Cu Alloys
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作者 QU Shuwei LI Zejun +4 位作者 WANG Hongfu TIAN Xiaoguang QIAN Zhike LI Ruiqin YAO Wei 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1759-1765,共7页
This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined wi... This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined with optical microscopy and electron backscatter diffraction(EBSD)analysis demonstrate that increasing undercooling(ΔT)can induce a consistent sequence of microstructural transitions:coarse dendrites,fine equiaxed grains(first refinement),oriented fine dendrites,and fine equiaxed grains(second refinement).Two distinct grain refinement events are identified,with critical undercooling thresholds(ΔT)dependent on composition:increasing Cu content increases the critical undercoolingΔT*required for the second refinement(Cu55Ni45:227 K;Cu60Ni40:217 K;Ni65Cu35:200 K).The BCT(Bridgman Crystal Growth)model quantitatively elucidates this behavior,revealing a shift from solute-diffusion-dominated growth at low undercooling to thermally dominated diffusion at high undercooling(ΔT).Crucially,refined grains at high undercooling exhibit smaller sizes(10μm)and higher uniformity than those at low undercooling(20μm).These findings provide fundamental insights into non-equilibrium solidification mechanisms and establish a foundation for designing high-performance Ni-Cu alloys via deep undercooling processing. 展开更多
关键词 deep undercooling Ni-Cu alloys microstructural evolution grain refinement BCT model rapid solidification
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Differential energy pathways are required for rapid long-term memory formation in the oriental fruit fly,Bactrocera dorsalis
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作者 Jinxin Yu Jiayi He +5 位作者 Xuefeng Zhang Chuxiao Lin Shiyan Liu Xin Gong Xinnian Zeng Jiali Liu 《Journal of Integrative Agriculture》 2025年第8期3155-3168,共14页
To ensure the reliability of learned information,most insects require multiple intervals of experience before storing the information as long-term memory(LTM),and this requirement has been validated in insects from th... To ensure the reliability of learned information,most insects require multiple intervals of experience before storing the information as long-term memory(LTM),and this requirement has been validated in insects from the behavioral to the molecular level.Recent studies have shown that some insects can form LTM after one-trial experience,although the mechanisms underlying one-trial LTM formation are not well understood.Therefore,understanding the mechanisms underlying rapid learning and subsequent preference formation in insects is crucial.Here we show that the agricultural pest Bactrocera dorsalis can rapidly form LTM,which is dependent on protein synthesis,and that the formation of LTM requires high energy support at the cost of reduced survival.Furthermore,based on a liquid chromatography-mass spectrometry(LC-MS)metabolomics approach,we found that LTM-related processes are sequentially coupled to two processes for energy generation,the TCA cycle and oxidative phosphorylation.This was further confirmed by blocking these energy generation processes.Our results provide a theoretical basis for the development of behavioral modulators in oriental fruit flies that target energy generation metabolites,as well as a new perspective on the rapid formation of LTM in insects. 展开更多
关键词 Bactrocera dorsalis rapid learning long-term memory protein synthesis energy generation
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Rapid escalation and release of risks to forest ecosystems triggered by warming:Insights from tree growth synchrony in temperate forests
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作者 Liangjun Zhu Danyang Yuan +5 位作者 J.Julio Camarero David J.Cooper Mai-He Li Shuguang Liu Xiaochun Wang Paolo Cherubini 《Forest Ecosystems》 2025年第4期769-780,共12页
Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapi... Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapidly and slowly warming periods in ecosystems with varying climatic conditions remains limited.By using tree-ring data from temperate broadleaf(Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Juglans mandshurica)and Korean pine(Pinus koraiensis)mixed forests in northeast China,we investigated the effects of climate change,particularly warming,on the growth synchrony of five dominant temperate tree species across contrasting warm-dry and cool-wet climate conditions.Results show that temperature over water availability was the primary factor driving the growth and growth synchrony of the five species.Growth synchrony was significantly higher in warm-dry than in cool-wet areas,primarily due to more uniform climate conditions and higher climate sensitivity in the former.Rapid warming from the 1960s to the 1990s significantly enhanced tree growth synchrony in both areas,followed by a marked reversal as temperatures exceeded a certain threshold or warming slowed down,particularly in the warm-dry area.The growth synchrony variation patterns of the five species were highly consistent over time,although broadleaves exhibited higher synchrony than conifers,suggesting potential risks to forest resilience and stability under future climate change scenarios.Growing season temperatures and non-growing season temperatures and precipitation had a stronger positive effect on tree growth in the cool-wet area compared to the warm-dry area.High relative humidity hindered growth in the cool-wet area but enhanced it in the warm-dry area.Overall,our study highlights that the diversity and sensitivity of climate-growth relationships directly determine spatiotemporal growth synchrony.Temperature,along with water availability,shape long-term forest dynamics by affecting tree growth and synchrony.These results provide crucial insights for forest management practice to enhance structural diversity and resilience capacity against climate changeinduced synchrony shifts. 展开更多
关键词 Tree rings Growth synchrony Forest resilience rapid warming Temperate forest Northeast China
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Multi-Scale Influencing Factors and Prediction of Interannual Variability in Rapid Intensification Magnitude of Northwest Pacific Tropical Cyclones
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作者 LI Yu-meng ZHAN Rui-fen DING Yi-hui 《Journal of Tropical Meteorology》 2025年第1期75-86,共12页
The rapid intensification(RI)magnitude of tropical cyclones(TCs)over the western North Pacific(WNP)exhibits significant interannual variability and is influenced by multiple factors across various scales.These factors... The rapid intensification(RI)magnitude of tropical cyclones(TCs)over the western North Pacific(WNP)exhibits significant interannual variability and is influenced by multiple factors across various scales.These factors primarily include:interannual factors—sea surface temperature(SST)in key regions of the WNP,eastern Indian Ocean SST,El Niño-Southern Oscillation(ENSO),South Pacific Subtropical Dipole(SPSD),and western Pacific teleconnection;decadal factors—Atlantic Multidecadal Oscillation(AMO)and Pacific Decadal Oscillation(PDO);and longer-term factor—global warming.This study systematically analyzes these factors and their potential impacts,quantitatively assessing their relative importance.A statistical prediction model for the WNP TC-RI magnitude is developed based on ridge regression methods.The results indicate that the influence of these factors on the RI magnitude is closely related to the large-scale thermodynamic and dynamic conditions.Among them,the SPSD plays the most critical role in the interannual variability of the RI magnitude,followed by global warming and the AMO.Further analysis reveals that the statistical prediction model based on multiple factors demonstrates good predictive skill for the interannual variability of the TC RI magnitude. 展开更多
关键词 western North Pacific tropical cyclone rapid intensification interannual variability multis-cale factors
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A Potentially Shared Neural Basis Linking Rapid Saccades and Avoidance Initiation in the Superior Colliculus Driven by Visual Threats
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作者 Zhou Sun Yu Gu 《Neuroscience Bulletin》 2025年第6期1115-1118,共4页
Throughout the lifespan,an animal can encounter predators frequently,thus the ability to avoid attacks from predators is crucial for its survival.The chances of evading danger can be greatly improved if the animal can... Throughout the lifespan,an animal can encounter predators frequently,thus the ability to avoid attacks from predators is crucial for its survival.The chances of evading danger can be greatly improved if the animal can respond immediately to the threat.Therefore,when an animal detects a threat through its visual system,it must quickly direct its gaze and attention toward the source of danger,assess the threat level,and take appropriate action. 展开更多
关键词 avoidance initiation threat assessment gaze direction survival visual systemit visual threats superior colliculus rapid saccades
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