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节能 2024年第1期43卷 119-121页

作者：尚永锋袁润东杨申中国民用航空飞行学院航空工程学院四川广汉618307

航空运输业碳排放较高,因此计划用氢能源代替传统航空燃油以降低碳排放,以氢燃料电池和氢燃料航空发动机作为飞机的动力源。围绕氢能源本身,对氢燃料电池和氢燃料航空燃气涡轮发动机展开论述,总结氢能源发展的主要技术难题,为氢能源飞... 详细信息

航空运输业碳排放较高,因此计划用氢能源代替传统航空燃油以降低碳排放,以氢燃料电池和氢燃料航空发动机作为飞机的动力源。围绕氢能源本身,对氢燃料电池和氢燃料航空燃气涡轮发动机展开论述,总结氢能源发展的主要技术难题,为氢能源飞机发展提供参考。

关键词：氢能源氢燃料电池氢燃料航空发动机航空减碳

Sediment Transport Capacity Under the River–Tide Interaction in the Changjiang Estuary

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China Ocean Engineering 2019年第2期33卷 207-218页

作者： feng Zhi-yong TAN Guang-ming XIA Jun-qiang State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan University

Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has been studied extensively by many researchers in the last decades. Nevertheless, the underlying mechanism behind sediment transport capacity in estuaries remains poorly understood. The current study aims to explore the impact of the river–tide interaction on sediment transport and establish a formula of sediment transport capacity under the river–tide interaction. The impact of the river–tide interaction on the hydrodynamics and sediment dynamics in the Changjiang Estuary was analyzed, a practical method for describing the variation in tide-runoff ratio was established,and a formula of sediment transport capacity considering the impact of river–tide interaction was proposed by introducing the tide-runoff ratio. The new method bridged the gap between two well-known sediment transport capacity methods by considering the variation in the index a for the gravitational term and overcomes the drawback of distinguishing flood/dry season or spring/ebb tide in the calculation of estuarine sediment transport. A large amount of flow and sediment data obtained from the Changjiang Estuary were collected to verify the proposed formula. The effect of salt-fresh water mixture and the morphological evolution on sediment transport capacity of the Changjiang Estuary were discussed.

关键词： sediment transport capacity river tide interaction hydrodynamics and sediment dynamics Changjiang Estuary (Yangtze Estuary)

TLC-SERS同时检测降压类保健食品中五种沙坦类违禁添加成分

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光谱学与光谱分析 2024年第5期44卷 1354-1363页

作者：黄丽俊庄顺钱冯永巍杨方威孙震谢云飞薛庆海无锡市食品安全检验检测中心江苏无锡214412 江南大学食品学院江苏无锡214122

由于人们不健康的饮食结构和生活作息习惯以及人口老龄化等因素,高血压等慢性病发病率逐渐增高,降压类保健食品逐渐受到人们青睐。但是市场中存在不良商家为了提高保健食品的功效,向保健食品中非法添加降压药,尤其是沙坦类降压药的现象... 详细信息

由于人们不健康的饮食结构和生活作息习惯以及人口老龄化等因素,高血压等慢性病发病率逐渐增高,降压类保健食品逐渐受到人们青睐。但是市场中存在不良商家为了提高保健食品的功效,向保健食品中非法添加降压药,尤其是沙坦类降压药的现象。建立了一种薄层色谱层析技术(TLC)与表面增强拉曼光谱(SERS)联用方法,对降压类保健食品中五种可能添加的沙坦类违禁成分(奥美沙坦酯、厄贝沙坦、氯沙坦钾、替米沙坦、缬沙坦)进行同步检测。对五种药物的SERS检测最佳条件进行探究,并通过比较不同成分及配比的TLC展开剂对于五种药物的分离效果,经过大量配方试验后成功得到环己烷-乙酸乙酯-甲醇-冰醋酸=53∶35∶12∶0.25(v/v/v/v)的分离体系,对五种药物具有良好的分离效果。确定实验条件后利用TLC分离技术对样品溶液分别进行初步分离,在薄层板上不同比移值的斑点原位处滴加金胶进行SERS检测,对样品溶液在斑点原位处的SERS光谱进行采集、比较,确定。研究结果表明,五种沙坦类违禁添加成分可通过TLC明确分离,且其SERS光谱特征峰一致、重复性良好,根据各自的特征峰可快速定性分析,检出限在0.1~1 mg·kg^(-1)之间。研究建立的TLC-SERS方法简单、快速,能够为保健食品中违禁添加成分的现场初步快速筛查提供一定参考。

关键词：降压类保健食品沙坦类药物薄层色谱层析-表面增强拉曼光谱联用技术同步检测

Advances in phase relationship for high Nb-containing TiAl alloys

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Rare Metals 2016年第1期35卷 15-25页

作者： yong-feng Liang Xiang-Jun Xu Jun-Pin Lin State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Materials and Chemistry School Zhongyuan University of Technology

γ-TiAl alloys,including two categories（the conventional TiAl and the high Nb-containing TiAl（high Nb-TiAl））,are technologically intriguing because of their applications at high ***,the service temperature of the high Nb-TiAl alloys is 60-100℃higher than that of conventional TiAl *** developed TiAl alloys,for example TNB,TNM,β-γ alloys,belong to the high Nb-TiAl alloys,displaying similar behavior in phase transformation,strengthening,oxidation at high temperatures,and relationships between composition,microstructure,and mechanical *** work presents an in-depth review of the high Nb-TiAl alloys regarding the advances in phase diagram,formation mechanism of the new γ_1 phase,microsegregation induced by adding a high content of alloying element Nb,and the mechanism of the B2/ω phase *** challenges in developing the high Nb-TiAl alloys are also discussed.

关键词： TiAl alloy Nb addition Phase diagram Microsegregation Microstructure

On the Evolution of the Apparent Size of Gamma-Ray Burst Remnants

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 305-311页

作者： Ting-Ting Gao yong-feng Huang Department of Astronomy Nanjing University Nanjing 210093

The remnants of two gamma-ray bursts, GRB 030329 and GRB 041227, have been resolved by Very Long Baseline Interferometry observations. The radio counterparts were observed to expand with time. These observations provide an important way to test the dynamics of the standard fireball model. We show that the observed size evolution of these two events cannot be explained by a simple jet model, rather, it can be satisfactorily explained by the two-component jet model. It strongly hints that gamma-ray burst ejecta may have complicated structures.

关键词： gamma rays: bursts - ISM: jets and outflows

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改进声发射信号的桥梁焊缝裂纹识别仿真研究

计算机仿真 2024年第2期41卷 163-166,217页

作者：李敏峰周小龙徐永峰河北建筑工程学院土木工程学院河北张家口075000 兰州交通大学土木工程学院甘肃兰州730070

针对因环境中存在过多噪声,导致桥梁焊缝裂纹识别精准度低的问题,提出基于声发射信号的桥梁焊缝裂纹识别方法。利用传感器提取桥梁周围的实时信号,通过信号在周期序列上的幅值变化,判定噪声信号,采用小波变换算法对噪声信号实施重构变换... 详细信息

针对因环境中存在过多噪声,导致桥梁焊缝裂纹识别精准度低的问题,提出基于声发射信号的桥梁焊缝裂纹识别方法。利用传感器提取桥梁周围的实时信号,通过信号在周期序列上的幅值变化,判定噪声信号,采用小波变换算法对噪声信号实施重构变换,建立硬阈值和软阈值函数,约束噪声信号。采用神经元传递函数计算原始信号序列中隐含层神经元的具体特征表现参数,得到信号的特征类间平均值,通过类间参数求得特征量。以带有声发射信号提取技术的传感器作为识别载体,将特征参数输入到识别传感器中,针对不同的桥梁测试点,建立焊缝裂纹识别通道,完成有效识别。实验结果证明,所提方法的识别精准度较高,无论是以持续频率还是持续时间信号作为测试指标,均能实现高效识别。

关键词：声发射信号桥梁焊缝裂纹硬阈值神经元传递函数隐含层神经元

Progress in Joining Ceramics to Metals

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Journal of Iron and Steel Research International 2006年第2期13卷 1-5页

作者： ZHANG yong feng Di HE Zhi-yong CHEN Xi-chun High Temperature Materials Research Institute Central Iron and Steel Research Institute Beijing 100081 China

The research and development of joining methods of ceramics to metals, especially brazing, diffusion bonding and partial transition liquid phase bonding, were introduced. Some opinions were put forward. For new composites emerging, it is necessary to develop new joining methods, particularly in the field of high temperature technique for joining ceramics to superalloys.

关键词： ceramic metal joining progress

Intelligent model prediction of fluctuant increase of maximum electric field in XLPE insulation using long short-term memory network algorithm

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High Voltage 2023年第1期8卷 70-80页

作者： Weiwang Wang Jiaju Lv yong feng Xinyuan Li Shengtao Li State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina

The electric field distortion due to space charge accumulations plays a significant role in the ageing,degradation and breakdown in failure of HVDC power ***,limited experimental results of the electric field dominated by space charges are insufficient to diagnose the power *** paper proposes an improved long short-term memory network(LSTM)model for predicting the fluctuating maximum electric field(Emax)in cross-linked polyethylene(XLPE)cable *** various Emax data derived from the complex space charge behaviours were measured using the pulsed electroacoustic *** model uses regularisation and dropout feedback in the LSTM unit,reducing the phenomenon of over-fitting due to the limited *** enhances the prediction accuracy and ability of long time prediction by improving the prediction of Emax with the non-linear *** predicted Emax approaches 190 kV/mm under 150 kV/mm and 60°C after 2 *** predicted large variation in Emax under 120 kV/mm and 20°C after 4 h ranges from 130 to 160 kV/*** indicates high electric stress in the cable insulation during continuous *** proposed LSTM model is of great importance to guide the diagnosis of cable degradation in HVDC power cables.

关键词： network prediction insulation

高标准农田建设适宜性评价和优先级分区——以陕西省大荔县为例

维普期刊数据库评论

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地球科学与环境学报 2024年第5期46卷 595-605页

作者：徐通张永锋赵志江董秀梅杜宜春新疆地质工程有限公司陕西省土地工程建设集团有限责任公司

为了提高陕西省高标准农田建设的效益和效率，加强农田生态保护，以陕西省大荔县为研究对象，基于生态位理论构建适合关中平原的高标准农田建设适宜性评价和优先级分区方法。该方法选取了土壤条件、基础设施、景观格局和生态约束等4个... 详细信息

为了提高陕西省高标准农田建设的效益和效率，加强农田生态保护，以陕西省大荔县为研究对象，基于生态位理论构建适合关中平原的高标准农田建设适宜性评价和优先级分区方法。该方法选取了土壤条件、基础设施、景观格局和生态约束等4个维度的15个评价因子，通过比较评价因子的现实生态位和理想生态位，计算各评价单元的建设适宜度和障碍度。根据建设适宜度、障碍度和障碍因子改造难度的综合分级，进行高标准农田工程建设优先级分区。对大荔县72 379个农田图斑的定量评价结果显示，大荔县高标准农田建设适宜性总体较好，优先建设区和次优先建设区耕地占55.66%,适宜工程选址和建设，只要稍加改造即可达到高标准农田建设要求。土壤条件和基础设施的障碍因素主要是有效土层厚度和有机质含量，而景观格局和生态约束维度的主要障碍因素是田块规模和灌溉水源。同时，提出了提升土壤有机质含量、增加有效土层厚度、降低耕地碎片化程度等方面的建议。综合来看，生态位理论对大荔县高标准农田建设适宜性评价和优先级分区具有较好的适用性。

关键词：生态位适宜性评价优先级分区障碍度高标准农田关中平原

Effect of microstructure and passive film on corrosion resistance of 2507 super duplex stainless steel prepared by different cooling methods in simulated marine environment

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1100-1114页

作者： Min Zhu Qiang Zhang yong-feng Yuan Shao-yi Guo School of Mechanical Engineering&Automation Zhejiang Sci-Tech UniversityHangzhou 310018China National and Local Joint Engineering Research Center of Reliability Analysis and Testing for Mechanical and Electrical Products Zhejiang Sci-Tech UniversityHangzhou 310018China

The effect of microstructure and passive film on the corrosion resistance of 2507 super duplex stainless steel(SDSS)in simulated marine environment was investigated by electrochemical measurements,periodic wet–dry cyclic corrosion test,scanning Kelvin probe force microscopy,atomic force microscopy,and X-ray photoelectron *** results show that the occupation ratio ofγphase increases with the decrease in cooling rate,whereas the content ofαphase reduces *** addition,theσprecipitated phase only emerges in the annealed *** pitting sensitivity and corrosion rate of 2507 SDSS reduce first and then increase as the cooling rate ***σprecipitated phase drastically reduces the protective ability of the passive film and facilitates micro-galvanic corrosion of the annealed *** various microstructures,the pits are preferentially distributed within theσandγ*** corrosion resistance of 2507 SDSS prepared by different cooling methods is closely related to the microstructure and structure(stability and homogeneity)of the passive *** steel shows an optimal corrosion resistance,followed by the quenched and annealed steels.

关键词： stainless steel microstructure corrosion resistance passive film