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聊城师院学报（自然科学版） 1999年第3期12卷 19-21,33页

作者：刁述妍庄步科冯向明临沂教育学院临沂276001

以理想费米气体和理想玻色气体为工作物质，研究了两种可逆循环的效率。

关键词：理想费米气体和理想玻色气体可逆循环效率

晶体塑性有限元方法在增材制造金属材料力学性能研究中的应用

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材料导报 2024年第1期38卷 177-186页

作者：冯振宇张宏宇马佳威陈琨周良道沈培良陈向明中国民航大学安全科学与工程学院天津300300 上海飞机设计研究院上海201210 中国飞机强度研究所西安710065

增材制造作为先进制造技术的代表,已被广泛应用于航空航天等高新技术领域。金属增材制造技术的高能量密度、高热和快速冷却等复杂工艺特点使得成形件的微观结构与传统制造技术所得成形件显著不同,这对金属材料力学性能有着重要影响。晶... 详细信息

增材制造作为先进制造技术的代表,已被广泛应用于航空航天等高新技术领域。金属增材制造技术的高能量密度、高热和快速冷却等复杂工艺特点使得成形件的微观结构与传统制造技术所得成形件显著不同,这对金属材料力学性能有着重要影响。晶体塑性有限元方法将晶体塑性理论与有限元方法相结合,能够跨尺度分析增材制造金属材料微观结构与力学性能之间的关系,为优化工艺过程提供支撑。本文综述了近年来晶体塑性有限元方法在金属增材制造中的应用,阐述了代表增材制造金属材料微观结构特征的几何模型的建立方法和有限元应用,提出了相关发展趋势。

关键词：增材制造晶体塑性有限元微观结构力学性能

Development of Bionic UAVs Cluster Technology

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第S1期35卷 1-8页

作者： Ma Chunyao feng Zhuoqun Zheng xiangming College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

With the wider use of UAV in various fields,the raising task complexity and the increasing environmental uncertainties,the higher requirements for UAV technology are put *** bionic UAV cluster system has the potential advantages of good stealth performance,strong environmental adaptability,wide expansion of task and high operational *** has excellent prospects in future information warfare,electronic warfare and conventional combat *** reviewing the development of bionic UAV cluster technology,this paper summarizes and analyzes the latest research progresses of the key technologies such as aerodynamic mechanism and aerodynamic configuration design,driving mechanism design,autonomous flight control,adaptive networking and cluster control of bionic aircrafts.

关键词： bionic UAV aerodynamic mechanism structure design ad-hoc networks cluster control

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垃圾渗滤液排污管结垢原因分析及防治对策

工业安全与防尘 2000年第9期26卷 29-32页

作者：陈石黄凯兴王克虹冯向明孟了深圳市罗湖区清水河下坪固体废弃物填埋场 518019

针对深圳市下坪垃圾填埋场渗滤液排污管道结垢现象 ,从结垢物组成分析、水质情况、管道设计、管道使用方法等方面 ,就其结垢原因进行分析探讨。

关键词：垃圾渗滤液排污管结垢现象防治方法分析方法热失重分析技术

天然硅藻土作为吸附材料处理渗滤液的效果研究

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新疆环境保护 2008年第3期30卷 17-20页

作者：冯向明蒋建国李春萍郭权深圳市下坪固体废弃物填埋场深圳518001 清华大学环境科学与工程系北京100084

利用天然硅藻土在静态条件下对垃圾渗滤液中的氨氮和COD的吸附效果进行了研究。结果表明:天然硅藻土对于氨氮的去除效率只有14.1%;但对COD的去除效率可以达到70.1%;天然硅藻土对于COD的饱和吸附量和吸附速度明显高于其对氨氮的饱和吸附... 详细信息

利用天然硅藻土在静态条件下对垃圾渗滤液中的氨氮和COD的吸附效果进行了研究。结果表明:天然硅藻土对于氨氮的去除效率只有14.1%;但对COD的去除效率可以达到70.1%;天然硅藻土对于COD的饱和吸附量和吸附速度明显高于其对氨氮的饱和吸附量及吸附速度;在平衡浓度相当高的情况下,每克硅藻土具有吸附65.31mg COD的极限潜力。

关键词：填埋场渗滤液 COD 静态吸附硅藻土氨氮

揭示钠离子电池正极材料Na_(6-2x)Fe_(x)(SO_(4))_(3)(1.5≤x≤2.0)的结构及电化学性质

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Science Bulletin 2023年第17期68卷 1894-1903页

作者：赵阿龙汲方杰刘长禹张世豪陈柯安冯祥明陈卫华钟发平艾新平杨汉西方永进曹余良 College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China National Engineering Research Centre of Advanced Energy Storage Materials Changsha 410205China

铁基硫酸盐聚阴离子材料因其成本低廉、电化学性能优异等优点,是钠离子电池大规模应用最有前景的候选材料之一.尽管Na_(2)Fe_(2)(SO_(4))_(3),Na_(2)Fe_(1.5)(SO_(4))_(3),Na_(2.4)Fe_(1.8)(SO_(4))_(3)和Na_(2.4)Fe_(1.8)(SO_(4))_(3)等Na_(6-2x)Fe_(x)(SO_(4))_(3)(NFSO-x 1.5≤x≤2.0)材料在储钠方面取得了巨大成果,但这些NFSO-x的相和结构特性仍存在争议,难以实现具有最佳电化学性能的纯相材料.本文通过实验方法和密度泛函理论计算研究了6个具有不同x的NFSO-x样品,以分析其相和结构特性.结果表明在NFSO-x的1.6≤x≤1.7区域存在纯相,部分Na离子倾向于占据Fe位点以形成更稳定的框架.NFSO-1.7在NFSO-x样品中表现出最佳的电化学性能,具有高的放电容量(0.1 C时为104.5 mAh g^(-1),接近其理论容量105 mAh g^(-1))、出色的倍率性能(30 C时为81.5 mAh g^(-1)),并在10,000次循环中具有超长的循环稳定性,容量保持率为72.4%.本研究有助于阐明铁基硫酸盐聚阴离子材料的相和结构特征,以促进其在大规模储能中的应用.

关键词：钠离子电池理论容量电化学性质放电容量倍率性能电化学性能密度泛函理论计算聚阴离子

Machine-learning based ocean atmospheric duct forecasting:a hybrid model-data-driven approach

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The Journal of China Universities of Posts and Telecommunications 2023年第4期30卷 1-9页

作者： feng Yuting Gong Haobing Hao Xiaojing Gao Hui Guo xiangming Key Laboratory of Trustworthy Distributed Computing and Service Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Radio Wave Propagation Characteristics and Modeling Technology 22nd Research Institute of China Electronics Technology CorporationQingdao 266107China

The atmospheric duct is a vital radio wave *** methods of forecasting the atmospheric duct mainly include statistical analysis based on sounding observation data and mesoscale numerical model-based *** former can provide accurate duct information but is highly dependent on the acquisition of data *** latter is more practical but still lacks *** paper introduces machine learning to establish a novel meteorological parameter correction model for atmospheric duct *** detail,using the weather research and forecasting(WRF)model data and spatiotemporal characteristics as input,sounding data as label and extreme gradient boosting(XGBoost)model for training,the meteorological parameter correction effect is the best,i.e.,the accuracy of forecast meteorological parameters is improved by about 65.4%.Combining the mapping relationship between meteorological parameters and corrected atmospheric refractive index(CARI),and the transition mechanism of CARI to duct parameters,a new duct forecasting mechanism is *** to the high efficiency of numerical model and the accuracy of sounding data,the new duct forecasting mechanism has excellent *** comparing the duct forecasting results,the forecasting accuracy of the new duct forecasting model is significantly higher than that of the mesoscale model.

关键词： marine atmospheric duct neural network fitting machine learning forecasting mechanism

Mapping rice cropping systems using Landsat-derived Renormalized Index of Normalized Difference Vegetation Index （RNDVI） in the Poyang Lake Region, China

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Frontiers of Earth Science 2016年第2期10卷 303-314页

作者： Peng LI Luguang JIANG Zhiming feng Sage SHELDON xiangming XIAO Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal University Nanchang 330022 China Department of Botany and Microbiology Center for Spatial Analysis University of Oklahoma Norman OK 73019 USA

Mapping rice cropping systems with optical imagery in multiple cropping regions is challenging due to cloud contamination and data availability; development of a phenology-based algorithm with a reduced data demand is essential. In this study, the Landsat-derived Renorma- lized Index of Normalized Difference Vegetation Index （RNDVI） was proposed based on two temporal windows in which the NDVI values of single and early （or late） rice display inverse changes, and then applied to discriminate rice cropping systems. The Poyang Lake Region （PLR）, characterized by a typical cropping system of single cropping rice （SCR, or single rice） and double cropping rice （DCR, including early rice and late rice）, was selected as a testing area. The results showed that NDVI data derived from Landsat time-series at eight to sixteen days captures the temporal development of paddy rice. There are two key phenological stages during the overlapping growth period in which the NDVI values of SCR and DCR change inversely, namely the ripening phase of early rice and the growing phase of single rice as well as the ripening stage of single rice and the growing stage of late rice. NDVI derived from scenes in two temporal windows, specifically early August and early October, was used to construct the RNDVI for discriminating rice cropping systems in the polder area of the PLR, China. Comparison with ground truth data indicates high classification accuracy. The RNDVI approach highlights the inverse variations of NDVI values due to the difference of rice growth between two temporal windows. This makes the discrimination of rice cropping systems straightforward as it only needs to distinguish whether the candidate rice typeis in the period of growth （RNDVI 〈 0） or senescence （RNDVI 〉 0）.

关键词： Normalized Difference Vegetation Index(NDVI) Renormalized Index of NDVI (RNDVI) ricecropping systems phenology temporal windows PoyangLake Region (PLR)

Recent advances in mitochondria-and lysosomes-targeted small-molecule two-photon fluorescent probes

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Chinese Chemical Letters 2017年第10期28卷 1943-1951页

作者： Peng Ning Wenjuan Wang Man Chen Yan feng xiangming Meng School of Chemistry and Chemical Engineering & Center for Atomic Engineering of Advanced Materials & Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials Anhui University Hefei 230601 China

Mitochondria and lysosomes are essential cellular organelles in most eukaryotic cells by playing the physiological roles to support the normal functions of cells, as well as the life of the whole body. To date,small-molecule fluorescent probes have been considered as one of the vital tools for monitoring and visualizing multiple biological analytes. This review summarized the recent advances in small-molecule two-photon fluorescent probes for metal ions, reactive oxygen species（ROS） and reactive sulfur species（RSS）, and changes inside micro-environment（e.g., p H, viscosity and polarity） in mitochondria and lysosomes, or served as mitotracker and lysotracker with the assistance of two-photon microscopy.

关键词： Two-photon absorption Fluorescent probe Localization Mitochondria Lysosomes

Changes in rice cropping systems in the Poyang Lake Region, China during 2004-2010

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Journal of Geographical Sciences 2012年第4期22卷 653-668页

作者： LI Peng feng Zhiming JIANG Luguang LIU Yujie XIAO xiangming Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100049China Department of Botany and Microbiology Center for Spatial AnalysisUniversity of OklahomaNorman 73019OKUSA

Rice cropping systems not only characterize comprehensive utilization intensity of agricultural resources but also serve as the basis to enhance the provision services of agro-ecosystems. Yet, it is always affected by external factors, like agricultural policies. Since 2004, seven consecutive No.1 Central Documents issued by the Central Government have focused on agricultural development in China. So far, few studies have investigated the effects of these policies on the rice cropping systems. In this study, based upon the long-term field survey information on paddy rice fields, we proposed a method to discriminate the rice cropping systems with Landsat data and quantified the spatial variations of rice cropping systems in the Poyang Lake Region （PLR）, China. The results revealed that：（1） from 2004 to 2010, the decrement of paddy rice field was 46.76 km2 due to the land use change. （2） The temporal dynamics of NDVI derived from Landsat historical images could well characterize the temporal development of paddy rice fields. NDVI curves of single cropping rice fields showed one peak, while NDVI curves of double cropping rice fields displayed two peaks annually. NDVI of fallow field fluctuated between 0.15 and 0.40. NDVI of the flooded field during the transplanting period was relatively low, about 0.20±0.05, while NDVI during the period of panicle initiation to heading reached the highest level （above 0.80）. Then, several temporal windows were determined based upon the NDVI variations of different rice cropping systems. （3） With the spatial pattern of paddy rice field and the NDVI threshold within optimum temporal windows, the spatial variation of rice cropping systems was very obvious, with an increased multiple cropping index of rice about 20.2% from 2004 to 2010. The result indicates that agricultural policies have greatly enhanced the food provision services in the PLR, China.

关键词： rice cropping systems NDVI temporal windows threshold method Landsat the Poyang Lake region(PLR)