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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 165-168页

作者： Xiang-jie Wang Jian-zhong Cui yu-bo Zuo zhi-hao Zhao Hai-tao Zhang Key Lab of Electromagnetic Processing of Materials （Ministry of Education） Northeastern University Shenyang 110004 China

To improve the quality of 7050 aluminum alloy ingots, low-frequency electromagnetic （LFE） field was applied during the conventional hot-top casting process. Macrostructures and microstructures of the ingots by the conventional and LFE hot-top casting processes were studied. The experimental results show that when the LFE field is turn off during the hot-top casting process, cold folding appears, and the as-cast structure becomes very coarse. Additionally, the thickness of the shell zone is much thinner during the low-frequency electromagnetic hot-top casting process than that during the conventional hot-top casting process. Some reasons for low-frequency electromagnetic field improving the surface quality, refining the structure of the ingot, and minimizing the thickness of the shell zone have been studied.

关键词： aluminum alloys solidification surface quality electromagnetic field

Protective effects of pinacidil hyperpolarizing cardioplegia on myocardial ischemia reperfusion injury by mitochondrial KATP channels

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Chinese Medical Journal 2011年第24期124卷 4205-4210页

作者： yu Tian FU Xiao-yun LIU Xing-kui yu zhi-hao Department of Anesthesiology Zunyi Medical College ZunyiGuizhou 563003 China

Background Many studies have indicated that hyperpolarizing cardioplegia is responsible for myocardial preservation and researchers have suggested that the adenosine triphosphate-sensitive potassium channels （KATe） were the end effectors of cardio-protection. But whether mitochondrial KATe plays an important role in hyperpolarizing cardioplegia is not apparent. The present study investigated the effect of hyperpolarizing cardioplegia containing pinacidil （a nonselective KATe opener） on ischemia/repeffusion injury in rat hearts, especially the role of mitochondrial KATe in pinacidil hyperpolarizing cardioplegia. Methods Sprague-Dawley rat hearts were Langendorff-perfused for 20 minutes with Krebs-Henseleit buffer at 37℃ before equilibration. Cardiac arrest was then induced in different treatments： there was no arrest and ischemia in the normal group, the control group were arrested by clamping the aorta, depolarizing caidioplegia （St. Thomas solution containing 16 mmol/L KCI） and hyperpolarizing cardioplegia groups used St. Thomas solution containing 0.05 mmol/L pinacidil and 5 mmol/L KCI to induce cardiac arrest in group hyperkalemic and group pinacidil, in group hyperkalemic ＋ 5-hydroxydecanote （5HD） and Pinacidil ＋ 5HD, 5HD （0.1 retool/L） was added to the above two solutions to block mitochondria KATe channels. Global ischemia was then administrated for 40 minutes at 37℃, followed by 30 minutes of reperfusion. At the end of equilibration and reperfusion, hemodynamics, ultrastructure, and mitochondrial function were measured. Results In the control group, ischemia/reperfusion decreased the left ventricular developed pressure, heart rate, coronary flow, mitochondrial membrane potential, impaired mitochondrial respiratory function, increased reactive oxygen species and left ventricular end diastolic pressure. Damage to myocardial ultrastructure was also evident. Both depolarized arrest and especially hyperpolarized cardioplegia significantly reduced these lesions

关键词： cardioplegic solutions heart arrest pinacidil ischemia/reperfusion injury myocardial mitochondrial ultrastructure potassium channel blockers

Association of host plant growth and weed occurrence with armyworm(Mythimna separata) damage in corn fields

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Journal of Integrative Agriculture 2018年第7期17卷 1538-1544页

作者： ZHANG Kun-peng yu zhi-hao JIANG Shi-xiong SUN De-wen HUI Jun-tao ZHENG yu-liang LI Xiao-zhen WANG Xing-yun WU Jun-xiang State Key Laboratory of Crop Stress Biology in Arid Areas/College of Plant Protection Northwest A&F UniversityYangling 712100P.R.China Anyang Institute of Technology Anyang 455000P.R.China Plant Protection and Quarantine Station of Sanyuan County Sanyuan 713800P.R.China Plant Protection and Quarantine Station of Lantian County Lantian 710500P.R.China Plant Protection and Quarantine Station of Chang'an District Chang'an 710100P.R.China Zhengping Plant Protection Technology Limited Company Xi'an 710000P.R.China

To clarify association between armyworm（Mythimna separata） damage level and the corn growth and weed occurrence, we investigated corn plant height, stem diameter and vigor as well as weed coverage and biomass. The investigations were conducted at three locations of Shaanxi Province, China which were suffered seriously from armyworm. Significant correlations were found between the parameters analyzed. At stunted corn growth and presence of plenty of weeds, the armyworm damage tended to be heavy; oppositely, when corn grew well and weed density were low, armyworm harm was the minimal. Therefore, corn growing status and weed density can significantly affect armyworm damage level. Our results imply that promoting corn growth and timely removal of weeds are conducive to reducing armyworm occurrence.

关键词： Mythimna separata damage degree corn growth corn field weeds

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基于流固耦合的旋翼结构振动载荷计算分析

振动工程学报 2020年第2期33卷 285-294页

作者：余智豪周云宋彬虞志浩康建鹏中国直升机设计研究所直升机旋翼动力学重点实验室江西景德镇333001 南京航空航天大学国家级直升机旋翼动力学重点实验室江苏南京210016

建立旋翼结构振动载荷的流固耦合分析方法,计算分析旋翼前飞状态下的结构振动载荷,其中旋翼动力学模型中采用大变形梁模型,旋翼气动模型采用CFD模型,利用多重滑移网格技术实现旋翼变距、旋转等运动,最后采取松耦合策略集成动力学、气动... 详细信息

建立旋翼结构振动载荷的流固耦合分析方法,计算分析旋翼前飞状态下的结构振动载荷,其中旋翼动力学模型中采用大变形梁模型,旋翼气动模型采用CFD模型,利用多重滑移网格技术实现旋翼变距、旋转等运动,最后采取松耦合策略集成动力学、气动模型。在结构和气动模型分别验证的基础上,通过计算SA349/2直升机桨叶在前飞状态的挥舞、摆振剖面结构振动载荷并对比飞行实测数据,验证流固耦合计算方法的准确性,同时对比自由尾迹模型计算结果,证明在旋翼结构振动载荷计算当中引入CFD方法能有效提高载荷计算的预估精度。

关键词：振动载荷直升机旋翼流固耦合大变形

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu hao-yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi Li zhi-Zhen Ren Liang Wang Wei-Chang hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

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精细时程积分法及其数值衍生格式应用评估

计算力学学报 2019年第1期36卷 132-137页

作者：吴杰王志东虞志浩江苏科技大学船舶与海洋工程学院镇江212003 南京航空航天大学直升机旋翼动力学国家级重点实验室南京210016

旋翼气动弹性耦合动力学方程本质上是一组刚性比较大的非线性偏微分方程。在有限元结构离散后,可改写为非齐次微分方程组,其中非齐次项是桨叶运动量(位移与速度)和气动载荷的函数。针对这类方程,本文尝试引入精细积分法及其衍生格式,借... 详细信息

旋翼气动弹性耦合动力学方程本质上是一组刚性比较大的非线性偏微分方程。在有限元结构离散后,可改写为非齐次微分方程组,其中非齐次项是桨叶运动量(位移与速度)和气动载荷的函数。针对这类方程,本文尝试引入精细积分法及其衍生格式,借助数值方法计算Duhamel积分项。从积分精度与数值稳定性方面比较研究具有代表性的精细库塔法和高精度直接积分法。结合隐式积分算法,评估精细积分法应用于旋翼动力学方程的可行性。算例表明,精细积分法对矩形直桨叶动力学方程具有足够的求解精度。

关键词：旋翼动力学偏微分方程精细积分法高精度直接积分法梯形方法

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旋翼桨叶结构载荷计算方法比较研究

振动与冲击 2014年第7期33卷 210-214页

作者：吴杰杨卫东虞志浩南京航空航天大学直升机旋翼动力学重点实验室南京210016

基于有限转角假设,建立了刚柔耦合旋翼动力学模型。该模型考虑了刚体转动与弹性变形之间的耦合效应,相较于基于小转角假设的传统有限元模型具有明显的优势。气动力以广义力形式与桨叶刚体转动及弹性变形耦合组建方程。在方程求解的单步... 详细信息

基于有限转角假设,建立了刚柔耦合旋翼动力学模型。该模型考虑了刚体转动与弹性变形之间的耦合效应,相较于基于小转角假设的传统有限元模型具有明显的优势。气动力以广义力形式与桨叶刚体转动及弹性变形耦合组建方程。在方程求解的单步上,分别采用力积分法、反力法以及曲率法计算桨叶剖面结构振动载荷。以BO105模型桨叶及SA349/2小铃羊直升机为仿真对象,比较研究了这三种载荷计算方法的预测精度与适用范围。对于不考虑气动力的纯结构振动载荷,三种计算方法具有相同的精度。在气弹瞬态计算中,力积分法对桨根载荷的预测精度不足。曲率法与反力法在桨叶有限元节点处得到了相近的结果。反力法预测精度取决于有限元建模精度,且只对节点处载荷有效。由于曲率法只计入弹性桨叶的弯曲曲率,该方法需要更高阶次的形函数以满足自由度二阶导数的连续性。此外,为加速收敛及减少累积误差,本文开发了基于外推法的数值积分算法。

关键词：旋翼动力学结构载荷力积分法反力法曲率法

MESOSCALE RAIN BELTS AND RAIN PEAKCLUSTER IN THE MEIyu PERIOD

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Science China Chemistry 1989年第6期32卷 737-748页

作者：余志豪陆汉城 Department of Atmospheric Sciences Nanjing University Meteorological Institute of Air Force PLA

The case of heavy rain on the meiyu front of June 24—27, 1981 is analysed by use of the mesoscale data with 45×45 km×50 hPa grid mesh. It is found that there exist some meso-α scale rain belts embedded in the area of the meiyu front, and a lot of meso-β scale rain peak cluster moving along these rain *** meso-α scale rain belts are corresponding to the mesoscale convergence lines and the tilting rotor circulation cells. Since the isentropic slope is relatively steep there, and even appears in folding, it satisfies the criterion of the conditional asymmetric instability. Thus, it can be recognized that the meso-α scale rain belts are triggered by the developing inertial-gravitational waves. However, the meso-β scale rain peak clusters are corresponding to the inertial-gravitational waves with the mixed vertical structure, which basically satisfies the instable criterion of the transversal waves.

关键词： meso-α and-β scale inertial-gravitational waves, conditional asymmetric instability.

Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： haonan Zhang Cheng hao Tongtong Fu Dian yu Jane Howe Kaiwen Chen Ning Yan hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

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含升力偏置的共轴刚性旋翼配平与响应分析

科学技术与工程 2020年第32期20卷 13466-13471页

作者：余智豪周云中国直升机设计研究所直升机旋翼动力学重点实验室景德镇333001

建立考虑升力偏置的共轴刚性旋翼气弹配平计算方法。在单旋翼气弹计算方法基础上,引入考虑双旋翼气动干扰的入流模型,针对大反流区气动力计算和大前进旋翼气弹配平计算进行相应修正,最终集成考虑升力偏置的共轴刚性旋翼气弹配平计算方法... 详细信息

建立考虑升力偏置的共轴刚性旋翼气弹配平计算方法。在单旋翼气弹计算方法基础上,引入考虑双旋翼气动干扰的入流模型,针对大反流区气动力计算和大前进旋翼气弹配平计算进行相应修正,最终集成考虑升力偏置的共轴刚性旋翼气弹配平计算方法,并开展考虑升力偏置的共轴双旋翼气弹配平分析。分析提前操纵角、升力偏置、前进比因素对双旋翼配平和响应的影响。研究表明,在中等前进比时,下旋翼拉力略大于上旋翼,气动效率优于上旋翼。大前进比下桨尖响应曲线呈现2阶特性而增加升力偏置使得响应曲线逐渐为1阶曲线变化,且提前操纵角对双旋翼操纵和桨尖间距均无影响。

关键词：共轴配平响应升力偏置