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不同燕麦品种在呼伦贝尔地区的引种适应性评价

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草业学报 2024年第4期33卷 60-72页

作者：李鸿飞周帮伟张淼施树楠李志坚东北师范大学草地科学研究所植被生态科学教育部重点实验室吉林长春130024 吉林省长岭县草原工作站吉林长岭131500

为筛选出适宜在呼伦贝尔地区种植的优质饲用燕麦品种,在该地引进18份燕麦种质资源作为供试材料并测试其区域适应性。本试验基于该地区田间种植环境,采取随机区组设计,对供试燕麦的主要生产性能、农艺性状、营养品质等指标进行分析比较,... 详细信息

为筛选出适宜在呼伦贝尔地区种植的优质饲用燕麦品种,在该地引进18份燕麦种质资源作为供试材料并测试其区域适应性。本试验基于该地区田间种植环境,采取随机区组设计,对供试燕麦的主要生产性能、农艺性状、营养品质等指标进行分析比较,采用灰色关联度分析法对供试品种的各项指标进行综合评价,旨在为该地区燕麦种质资源的适应性研究提供一定参考。结果表明:18份供试燕麦品种在呼伦贝尔地区均能发育成熟,生育期在76~109d,生长速率呈“慢-快-慢”的趋势。随着生育期的推进,供试燕麦的干草产量逐步增高并于灌浆期达到最大,伽利略(13.18 t·hm^(-2))干草产量最高,其次是甜燕3号(12.32 t·hm^(-2))、贝勒(12.25 t·hm^(-2)),显著高于其他燕麦品种(P<0.05)。贝勒(120 cm)株高最高,甜燕3号(117 cm)次之,二者显著高于其他供试燕麦品种(P<0.05)。福燕1号鲜干比(4.98)最高,白燕7号(1.74)茎叶比最低,说明二者具有较好的适口性。福燕1号的粗蛋白含量最高(13.46%),福燕2号的中性洗涤纤维及酸性洗涤纤维含量均为最低,说明二者具有较好的饲用品质。灰色关联度分析表明,本地区种植的燕麦应选择具有鲜干比大、叶片较大、茎秆粗壮、粗蛋白含量高、草产量高等特征的燕麦品种。甜燕3号、伽利略、福燕2号综合表现位居前列,可作为优良的饲用燕麦品种在当地推广种植。

关键词：燕麦生产性能营养品质灰色关联度分析呼伦贝尔地区

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Pressure Effects on Thermodynamics of Phase Behavior in Polystyrene/Methylcyclohexane Solutions

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Chemical Research in Chinese Universities 2007年第5期23卷 613-621页

作者： li hong-fei JIANG Shi-chun AN li-jia YU Dong-hong State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Section of Chemistry Department of Life Sciences Aalborg University Aalborg DK 9000 Denmark

The calculations presented in this paper are based on the Sanchez-Lacombe（SL）lattice fluid *** interaction energy parameter,g12/k,required in this approach was obtained by fitting the cloud points of polystyrene（PS）/methylcyclohexane（MCH）polymer solutions under *** SL lattice fluid theory was used to calculate the spinodals,the binodals,and the Flory-Huggins（FH）interaction parameter of the *** calculated results show that the SL lattice fluid theory can describe the dependences of thermodynamics of PS/MCH solutions on temperature and pressure very ***,the calculated enthalpy and the excess volume changes indicate that the Clausius-Clapeyron equation cannot be suitable to describe pressure effect on PS/MCH *** analysis on the thermodynamics of this system under pressure shows that the role of entropy is more important than the excess volume in the present case.

关键词： PS/MCH polymer solution Thermodynamics Pressure effect

Temperature Effect on the Mechanical Behavior of Acrylic Polymers under Quasi-static and Dynamic Loading

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上海交通大学学报 2004年第Z2期38卷 89-95页

作者： Tao Suo Yulong li hong Yu fei Xu Zhongbin Tang Lei li School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China Beijing Institute of Aeronautical Materials Beijing100095China

In this paper, the mechanical behavior of acrylic polymers at elevated temperature was investigated. Four acrylic polymers were tested at high strain rate by using compression Hopkinson bar and at quasi-static strain rate by using an Instron servo hydraulic axial testing machine with the testing temperature from 218K to 393K. The results show that the mechanical property of acrylic polymers depends heavily on the testing temperature. The yield stress and Young's modulus were found to decrease with increasing temperature at low strain rate. At very low temperature, the materials display typical brittle fracture; however their plasticity improves remarkably at high temperatures. The predictions of the mechanical behavior including the effect of temperature and strain rate using a proposed theoretical model have a good agreement with experimental results.

关键词： acrylic polymer compression Hopkinson bar quasi-static dynamic fracture

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富水软土层盾构隧道冷冻法加固施工关键技术

建筑机械 2024年第7期 71-75页

作者：李鸿飞唐湘隆易帅中交第二航务工程局有限公司湖北武汉430000 中国交建轨道交通分公司北京100088

文章依托某地铁区间隧道盾构工程施工项目,阐述了富水软土层泥水盾构冷冻法施工关键技术及其工程实践应用效果。研究认为,富水软土地层冷冻法施工中,采用比重1.26~1.27盐水(氯化钙溶液)循环传递冷量,利用冷冻钢片管对环外地层进行预冻... 详细信息

文章依托某地铁区间隧道盾构工程施工项目,阐述了富水软土层泥水盾构冷冻法施工关键技术及其工程实践应用效果。研究认为,富水软土地层冷冻法施工中,采用比重1.26~1.27盐水(氯化钙溶液)循环传递冷量,利用冷冻钢片管对环外地层进行预冻结加固,10d左右可成型冻结帷幕有效阻隔渗漏,而在施工中仍需利用检孔测温规避复杂介质局部冻结失效情况,以此保障人、机安全的操作环境。经工程实践验证,该技术在富水软土地层条件下应用效果良好,对于保障施工安全、质量具有良好的效益,可以为国内外类似实践工程提供有益参考。

关键词：轨道交通盾构冷冻法富水地层 ANSYS

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大别山区茶树春霜冻时空演变规律及风险区划

中国农业气象 2024年第1期45卷 67-78页

作者：曹强杨咸贵董世杰罗晓丹李鸿飞陈曦岳伟安徽省六安市气象局六安237000 广东省清远市气象局清远511518 安徽省农业气象中心合肥230031

基于大别山区35个国家气象观测站1971-2020年逐日气象资料,利用趋势面插值和ArcGIS技术,分析大别山区茶树春霜冻时空分布特征,依据自然灾害风险理论,选取致灾因子危险性、孕灾环境暴露性、承载体脆弱性和防灾减灾能力等评价因子,利用加... 详细信息

基于大别山区35个国家气象观测站1971-2020年逐日气象资料,利用趋势面插值和ArcGIS技术,分析大别山区茶树春霜冻时空分布特征,依据自然灾害风险理论,选取致灾因子危险性、孕灾环境暴露性、承载体脆弱性和防灾减灾能力等评价因子,利用加权综合评价法构建茶树春霜冻灾害综合风险评估模型,并基于ArcGIS技术开展风险区划。结果表明:(1)1971-2020年大别山区不同等级春霜冻发生日数均显著下降,发生总日数及轻度、中度、重度春霜冻发生日数均值分别为9.6、5.2、3.0和1.4d,气候倾向率分别为-1.45、-0.61、-0.54和-0.30d·10a-1;春霜冻发生日数与海拔高度和纬度呈正相关,大别山区北部春霜冻发生日数较南部下降趋势更明显。(2)大别山区茶树春霜冻高、中和低风险区分别占研究区总面积的16.67%、41.88%和41.45%;高风险区主要位于金寨县、岳西县、霍山县和英山县等海拔600m以上高山区域,信阳市及零星阴坡(北坡)地带;中风险区主要位于海拔低于600m的山区及大别山北麓部分低海拔地区,零星分布在南麓阴坡(北坡)低海拔地区;低风险区主要位于大别山南麓低海拔地区,零星分布在北麓阳坡(南坡)低海拔地区。大别山区茶树春霜冻风险精细化评估可为优化茶产业布局、提升防灾减灾能力提供参考。

关键词：茶树春霜冻风险区划大别山区

Fast charge transfer kinetics in Sv-ZnIn_(2)S_(4)/Sb_(2)S_(3)S-scheme heterojunction photocatalyst for enhanced photocatalytic hydrogen evolution

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Rare Metals 2024年第2期43卷 533-542页

作者： Wei li Jia-Jun li Zhi-fei liu hong-Yu Ma Peng-fei Fang Rui Xiong Jian-hong Wei Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution ***,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was *** introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution ***,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of *** a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) *** on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is *** work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

关键词： ZnIn_(2)S_(4) nanosheets S-scheme heterojunction Sulfur vacancy Charge transfer and separation Photocatalytic H_(2)evolution

Reshaping force for deformed casing repairing with hydraulic rolling reshaper and its influencing factors

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Petroleum Science 2024年第4期21卷 2745-2757页

作者： hong-fei li Min Luo Ting-Ting Xu Qiao-Zhen li Cong-Jian Huang School of Mechanical Science and Engineering Northeast Petroleum University

Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years. When it is used for well repair operation, the reshaping force provided by ground devices is generally determined by experience. However, too large reshaping force may destroy the deformed casing, and too small reshaping force may also prolong the construction period and affect the repairing effect. In this paper, based on Hertz contact theory and elastic-plastic theory, combined with the process parameters of shaping, and considering the structural characteristics of the deformed casing and reshaper, we propose a mathematical model for calculating the reshaping force required for repairing deformed casing by hydraulic rolling reshaper. Meanwhile, the finite element model and numerical method of hydraulic rolling reshaper repairing deformed casing are established by using the finite element method, and the reliability of the mathematical model is verified by several examples. On this basis, the control variable method is used to investigate the influence of each parameter on the reshaping force, and the influence degree of each parameter is explored by orthogonal simulation test and Pearson correlation analysis. The research results not only provide an important theoretical basis for the prediction of reshaping force in on-site construction, but also provide a reference for the subsequent improvement of the shaping process.

关键词： Hydraulic rolling reshaper Reshaping force Deformed casing Casing reshaping Hertz contact theory

Role of micro-Ca/In alloying in tailoring the microstructural characteristics and discharge performance of dilute Mg-Bi-Sn-based alloys as anodes for Mg-air batteries

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Journal of Magnesium and Alloys 2024年第1期12卷 251-266页

作者： fei-er Shangguan Wei-li Cheng Yu-hang Chen Ze-qin Cui Hui Yu hong-xia Wang li-fei Wang Hang li Hua Hou School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are *** grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing *** that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing *** electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical *** In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca *** micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly *** In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery.

关键词： Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors Discharge properties

Design strategies of high-performance lead-free electroceramics for energy storage applications

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Rare Metals 2024年第3期43卷 853-878页

作者： Biao Guo fei Jin li li Zi-Zhao Pan Xin-Wei Xu hong Wang Department of Materials Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055China School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the development of high-energy-density ceramic-based *** significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramies has been restricted due to environmental and health hazards of ***-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near ***,the energy density of lead-free ceramics is still lagging behind that of lead-containing ***,severely limiting their *** efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past *** review briefly discusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial *** prospects and challenges of lead-free ceramics for energy storage applications are also discussed.

关键词： Dielectric materials Lead-free ceramic Environment friendly Energy storage Design strategy