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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 148-154页

作者： Xiao-ming PENG ya-dong shang Xue-qin WANG School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou 510642China

This paper deals with an initial boundary value problem for a class of nonlinear wave equation with nonlinear damping and source terms whose solution may blow up in finite *** explicit lower bound for blow up time is ... 详细信息

关键词： lower bound blow up nonlinear wave equation nonlinear damping nonlinear source

Blow up of Solutions for a Nonlinear Petrovsky Type Equation with Time-dependent Coefficients

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 836-846页

作者： Xiao-xiao ZHENG ya-dong shang Xiao-ming PENG School of Mathematical Sciences Qufu Normal UniversityQufu 273155China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China

4In this paper,we study a nonlinear Petrovsky type equation with nonlinear weak damping,a superlinear source and time-dependent coefficients utt+△^2u-ki(t)|ut|m^2ut=k2(t)|u|^p-2u,x∈Ω,t>0,whereΩis a bounded domain in R^*** certain conditions on k1(t),k2(t)and the initial-boundary data,the upper bound for blow-up time of the solution with negative initial energy function is given by means of an auxiliary functional and an energy estimate met hod if p>***,a lower bound of blow-up time are obtained by using a Sobolev-type inequality and a first order differential inequality technique for n=2,3 and n>4.

关键词： nonlinear Petrovsky type equation time-dependent coefficients blow-up upper bound lower bound

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

A bio-inspired optical imaging method for robotic perception in turbid water

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Science China Technological Sciences 2025年第1期 79-81页

作者： Xudong SUN yafeng LI Peng LIN Xiaodi shang Xianping FU School of Information Science and Technology Dalian Maritime University College of Computer Science and Technology Qingdao University

In the realm of underwater robotics, optical imaging plays a pivotal role in many scientific researches. Due to the effects of absorption and scattering,images captured in turbid water are severely degraded. Therefore, enhancing the quality of underwater optical images stands paramount in ensuring the continued advancement and efficacy of underwater robots across its multifarious applications.

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Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia Xie Chengjia shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang shang-Xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun Bi Youxiang Chew shang Sui Chaolin Tan Zhenglin Du Jinlong Su Fern Lan Ng Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

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曲美他嗪治疗急性脑梗死的疗效探究

中国现代医学杂志 2018年第3期28卷 69-72页

作者：许春奇尚亚东程仁立瞿晓雅王婷婷王子春吕秀英安徽医科大学附属宿州医院急诊科安徽宿州234000

目的探究曲美他嗪治疗急性脑梗死的疗效。方法 92例急性脑梗死患者随机分为治疗组和对照组,各46例,治疗组在予阿司匹林、辛伐他汀、血栓通及奥拉西坦等常规治疗基础上,加用曲美他嗪20 mg,口服,3次/d。对照组:只用上述常规治疗,分别于治... 详细信息

目的探究曲美他嗪治疗急性脑梗死的疗效。方法 92例急性脑梗死患者随机分为治疗组和对照组,各46例,治疗组在予阿司匹林、辛伐他汀、血栓通及奥拉西坦等常规治疗基础上,加用曲美他嗪20 mg,口服,3次/d。对照组:只用上述常规治疗,分别于治疗前和治疗后第2周采用美国国立卫生院神经功能缺损程度评分标准(NIHSS)进行神经功能缺损评分,日常生活自理能力量表(ADL)检测患者日常生活自理能力,监测血C反应蛋白(CRP)浓度。同时,分别于治疗前和治疗后第1周抽静脉血查血栓弹力图(TEG)各指标和血小板聚集率(PAg T)。结果两组患者治疗后,NIHSS评分、ADL评分、CRP浓度、血栓最大幅度、综合凝血指数及PAGT均逐渐下降,反应时间、凝固时间及最大凝固时间均升高,两组比较,差异有统计学意义(P<0.05);治疗组总有效率较对照组升高,进展型脑梗死较对照组减少,且不增加药物副作用。结论曲美他嗪治疗急性脑梗死不仅具有抗栓作用,而且能改善患者神经功能缺损症状,提高生活自理能力,提高临床疗效,减少进展型脑梗死发生率,并且不增加药物副作用。

关键词：曲美他嗪急性脑梗死进展型脑梗死

Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan Wang Pan shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

Abnormally expressed circular RNAs as novel non-invasive biomarkers for hepatocellular carcinoma: A meta-analysis

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World Journal of Gastrointestinal Oncology 2019年第10期11卷 909-924页

作者： ya-Lin Jiang Meng-Meng shang Shi-Zhen dong Yong-Chao Chang Department of Clinical Laboratory The First Affiliated Hospital and College of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471003Henan ProvinceChina Department of Clinical Laboratory The Family Planning Guidance Station of Luanchuan CountyLuoyang 471500Henan ProvinceChina

BACKGROUND Circular RNAs(circRNAs)are a newly discovered class of endogenous noncoding RNAs that may have roles in cancer genesis and *** the recent literature,dysregulated circRNAs have been extensively investigated in hepatocellular carcinoma(HCC).Whether or not circRNAs are of clinical value for the management of HCC has not been *** To meta-analyze the diagnostic and prognostic value of abnormally expressed circRNAs in *** Eligible studies were sourced from PubMed,EMBASE,and CNKI online *** on patients’clinical characteristics,including diagnostic efficacy and overall survival,were *** diagnostic and prognostic parameters were respectively synthesized using the bivariate meta-analysis model and multivariate Cox hazard regression analysis based on Stata *** trim and fill method was adopted to assess the possible effects from publication *** A total of 21 eligible studies were *** pooled sensitivity,specificity,and area under the curve of abnormally expressed circRNAs in distinguishing HCC from non-cancer controls were 0.78(95%CI:0.69–0.85),0.80(95%CI:0.74–0.86),and 0.86,*** analyses showed that the downregulated circRNA expression signature correlated perfectly with HCC survival[hazard ratio(HR)=0.42,95%CI:0.19–0.91,P=0.028;I2=92.7%,P=0.000],whereas the HCC cases with high circRNA levels had significantly poorer prognoses than those of patients with low circRNA levels(HR=2.22,95%CI:1.50–3.30,P=0.000;I2=91%,P=0.000).Moreover,abnormally expressed circRNAs were intimately associated with tumor size,differentiation grade,microvascular invasion,metastasis,TNM stage,and serum alpha fetal protein level in patients with *** analysis based on sample type,control source,and expression status also yielded robust *** Abnormally expressed circRNA signatures show immense potential as novel non-invasive biomarker(s)for HCC diagnosis and prognosis.

关键词： CircRNA Hepatocellular carcinoma Diagnosis Prognosis Meta-analysis