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Uncertainty Analysis of Spatial Autocorrelation of Land-Use and Land-Cover Data within Pipestem Creek in North Dakota

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Journal of Geoscience and Environment Protection 2017年第8期5卷 71-88页

作者： Papia F. Rozario Peter G. Oduor Larry Kotchman Michael Kangas Environmental & Conservation Sciences North Dakota State University Fargo ND USA Department of Geosciences North Dakota State University Fargo ND USA state forester North Dakota Forest Service Molberg Forestry Center Bottineau ND USA nursery & state forest team leader North Dakota State University Fargo ND USA

A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction model is necessary to assess the change. Spatial prediction within a Geographic Information System (GIS) using Kriging is a popular stochastic method. The objective of this study was to predict spatial and temporal transformation of a small agricultural watershed—Pipestem Creek in North Dakota;USA using satellite imagery from 1976 to 2015. To enhance the difference between forested land and non-forested land, a spectral transformation method—Tasseled-Cap’s Greenness Index (TCGI) was used. To study the spatial structure present in the imagery within the study period, semivariograms were generated. The Kriging prediction maps were post-classified using Remote Sensing techniques of change detection to obtain the direction and intensity of forest to non-forest change. TCGI generated higher values from 1976 to 2000 and it gradually reduced from 2000 to 2011 indicating loss of forested land.

关键词： Kriging Tasseled Cap Greenness Index Land-Use and Land-Cover

Mg doping and native N vacancy effect on electronic and transport properties of AlN nanowires

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Science China(Technological Sciences) 2015年第5期58卷 832-841页

作者： QIN Mei SHANG Yan WANG Xiao ZHANG GuiLing Innovative Research team of Green Chemical Technology in University of Heilongjiang Province College of Chemical and Environmental Engineering Harbin University of Science and Technology

The effects of Mg doping(MgAl) and native N vacancy(VN) on the electronic structures and transport properties of Al N nanowire(Al NNW) were theoretically investigated by using density functional theory. Either the MgAl defect or the VN defect prefers to be formed on the Al NNW surfaces. Both MgAl and VN defects could increase the conductivity owing to introducing a defect band inside the band gap of Al N and split the Al N band gap into two subgaps. The defect concentration has little influence on the magnitude of the subgaps. The MgAl serves as a shallow acceptor rendering the nanowire a p-type conductor. The VN introduces a deep donor state enabling the nanowire an n-type conductor. The MgAl systems exhibit higher conductivity than the VN ones owing to the narrow subgaps of MgAl systems. The conductivity is roughly proportional to the defect concentration in the MgAl and VN defect systems. When the MgAl and VN coexist, the hole state of the MgAl defect and the electron state of the VN defect will compensate each other and their coupling state appears just above the valence-band maximum leading to a little decrease of the band gap compared with the pure Al NNW, which is unfavorable for the enhancing of the conductivity.

关键词： doping enabling rendering compensate introducing valence magnitude defects narrow nanotubes

Virtual Coupling Trains Based on Multi-Agent System Under Communication Delay

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Chinese Journal of Electronics 2024年第6期33卷 1545-1554页

作者： Guodong QIN Xiangxi MENG Tao WEN Baigen CAI School of Automation and Intelligence Beijing Jiaotong University The Institute of System Research China Industrial Control Systems Cyber Emergency Response Team

With the rapid development of railway transportation, virtual coupling(VC) has become a popular research topic. VC can greatly reduce tracking distance and increase the line capacity. Under VC control, the train formation control not only considers the behavior and speed adjustment strategy of the leader train but also the communication delays between trains. The quality of data communication between trains is an important aspect of train tracking control. We consider a virtually coupled train set(VCTS) as a multi-agent system. The Luenberger observer is introduced to estimate the real-time state of the train, based on the estimation, the train control consistency protocol is designed to account for communication delays. The stability of the error system is proven by constructing a Lyapunov function. The consistency of the coordinated train control is verified through simulation.

关键词： Couplings Protocols Transportation Observers Stability analysis Real-time systems Formation control Delays Multi-agent systems Lyapunov methods

Mental Functioning of Workers with Cancer Diagnosis by Brazilian Version of the Work Role Functioning Questionnaire—WRFQ-Br

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Health 2016年第14期8卷 1495-1505页

作者： Cristiane Helena Gallasch Neusa Maria Costa Alexandre Sergio Carlos Barros Esteves Eugenio Fuentes Pérez Júnior Magda Guimarães de Araujo Faria Elias Barbosa de Oliveira Priscila Cristina da Silva Thiengo Patricia Campos Pavan Baptista Faculty of Nursing Rio de Janeiro State University Rio de Janeiro Brazil Post Graduation Programs Professor Group of Studies and Researches in Occupational Health and Ergonomics Leader Faculty of Nursing State University of Campinas Campinas Brazil CAISM Hospital da Mulher Dr. José Aristodemo Pinotti State University of Campinas Campinas Brazil Post Graduation and Under Graduation Programs Professor Mental Health and Work Study Group Leader (GESMT) Faculty of Nursing Rio de Janeiro State University Rio de Janeiro Brazil Post Graduation and Under graduation Programs Professor Leader of the Group of Studies on the Health of Nursing Worker (GESTE) School of Nursing University of S&atilde o Paulo S&atilde o Paulo Brazil

Aim: To evaluate data related to mental work functioning of workers with cancer diagnosis in radiotherapy in a private service in the city of Campinas, state of São Paulo, Brazil. Method: It consists in a cross-sectional, observational and analytical study with comparison between cancer patients and healthy people, using the Brazilian version of the Work Role Functioning Questionnaire (WRFQ-Br). Descriptive and statistical analysis is performed by the Mann-Whitney test. Results: There was a significant difference between the groups in the evaluation of mental demand;however, the population diagnosed with malignant neoplasm submitted to radiotherapy had unexpected higher scores, reflecting lower mental exigency. Conclusions: The observed context may occur due to extensive support of family, government and interdisciplinary team of health care for individuals diagnosed with cancer. This data provide support for new research studies related to the importance of the work to promote mental health, considering aspects related to social interaction and productivity as the support system members. The importance of disseminating these results and limitation is based in the necessity of investments to improve research and actions to promote the permanence and early return to work for cancer survivors in Brazil and Latin America.

关键词： Neoplasms Mental Health Social Support Occupational Health Nursing

Nano research at China University of Petroleum:A special issue dedicated to the 70^(th)anniversary of China University of Petroleum

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Nano Research 2023年第10期16卷 11933-11937页

作者： Yuan Pan Yongming Chai Guiyuan Jiang Chunming Xu state Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China state Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China

In October 2023,China University of Petroleum will celebrate its 70th anniversary,as a scientific and technological support force in the field of petrochemical industry in China,China University of Petroleum has made significant contributions to the development of energy and chemical industry,cultivated a large number of outstanding talents,and promoted the development of energy and chemical *** the proposal of peaking carbon dioxide emissions and achieving carbon neutrality,China University of Petroleum actively transformed and made a series of breakthroughs in the fields of low-carbon chemical industry,new energy,and new materials,continuing to support the national energy strategy in the new *** celebrate China University of Petroleum’s 70^(th)anniversary,this special issue features a collection of scientific research and innovation achievements by the research team and alumni of China University of Petroleum,covering multidisciplinary topics including nanotechnology,catalysis,energy,chemical engineering,environment,devices,biology,*** special issue is aiming to show the research advances of China University of Petroleum in the field of nano *** University of Petroleum was established in Beijing in 1953,when the national economy was desperate for petroleum resources and the development of the petroleum industry was urgently needed professionals.

关键词： anniversary Petroleum breakthrough

Structure and spectral measurements of a new rubidium europium polyphosphate

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Rare Metals 2015年第12期34卷 877-881页

作者： Jing Zhu Hui Chen Yan Zheng Hui-Lan Kong Wen-Dan Cheng Yu-De Wang Hong-Tao Guan Zhong-Qi Zhu Department of Material Science and Engineering Yunnan University state Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

A new rubidium europium polyphosphate, RbEu(PO3)4, was synthesized by the high-temperature solution reaction and studied by single-crystal X-ray diffraction (XRD) technique. RbEu(PO3)4 belongs to the monoclinic space group P21/n (Z=4) and characterizes a three-dimensional framework made up from double PO4 spiral chains, RbO11, and EuO8 polyhedra. The absorption spectrum indicates that the compound has no absorption above 320nm with insulator characteristic. In addition, the infrared spectroscopy was carried out.

关键词： Inorganic compound Solid state synthesis Polyphosphate Crystal structure

Sodium Holmium Polyphosphate NaHo(PO_3)_4 with [P_4O_(12)]^(4-)Spiral Chains: Synthesis, Crystal Structure, and Luminescent Properties

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Chinese Journal of Structural Chemistry 2014年第4期33卷 619-625页

作者：朱静孔慧兰陈晖朱忠其 Department of Material Science and Engineering Yunnan University state Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Sodium holmium polyphosphate crystal, NaHo（PO3）4, has been synthesized by the high temperature solution reaction and characterized by X-ray diffraction analysis, EDX, IR, UV-vis-NIR, and PL spectra. The structure belongs to the monoclinic system, space group P21/n with Z = 4, α = 7.181（3）, b = 13.059（5） and c = 9.730 （4）？. It is described as a three-dimensional （3D） architecture made up of [P4O12]4- anionic spiral chains and HoO8 polyhedra by corner-sharing. The 8-coordinated sodium atoms are located in infinite tunnels. The results of EDX and IR spectrum are in good agreement with the crystallographic analysis. In addition, NaHo（PO3）4 exhibits visible light emission in the solid state at room temperature.

关键词： polyphosphate solid-state structure luminescence

High-entropy perovskite oxides: A versatile class of materials for nitrogen reduction reactions

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Science China Materials 2022年第10期65卷 2711-2720页

作者： Kaibin Chu Jingjing Qin Haiyan Zhu Michiel De Ras Chuang Wang Lei Xiong Longsheng Zhang Nan Zhang Johan A.Martens Johan Hofkens Feili Lai Tianxi Liu The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringInternational Joint Research Laboratory for Nano Energy CompositesJiangnan UniversityWuxi 214122China Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium state Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China Centre of Surface Chemistry and Catalysis:Characterisation and Application team KU LeuvenLeuven 3001Belgium Max Planck Institute for Polymer Research Ackermannweg 10Mainz 55128Germany

Despite the intense research efforts directed to electrocatalytic nitrogen reduction reaction(eNRR),the NH_(3) yield and selectivity are still not up to the standard of practical ***,high-entropy perovskite oxides with composition Bax(FeCoNiZrY)_(0.2)O_(3−δ)(Bx(FCNZY)_(0.2)(x=0.9,1)are reported as eNRR *** eNRR activity of high-entropy perovskite oxide is enhanced by changing the nonstoichiometric metal elements at the A-site,thus generating additional oxygen *** NH_(3) yield and Faraday efficiency for B_(0.9)(FCNZY)_(0.2) are 1.51 and 1.95 times higher than those for B(FCNZY)_(0.2),*** d-band center theory is used to theoretically predict the catalytically active center at the B-site,and as a result,nickel was identified as the catalytic *** free energy values of the intermediate states in the optimal distal pathway show that the third protonation step(*NNH_(2)→*NNH_(3))is the rate-determining step and that the increase in oxygen vacancies in the high-entropy perovskite contributes to nitrogen adsorption and *** work provides a framework for applying high-entropy structures with active site diversity for electrocatalytic nitrogen fixation.

关键词： high entropy perovskite nitrogen reduction reaction catalytic activity center

Effect of RE on molybdenum partitioning and resultant mechanical and microstructural behavior of a duplex stainless steel during hot working condition

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Journal of Rare Earths 2015年第1期33卷 107-112页

作者：陈雷马筱聪王明家薛红燕 National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University School of Mechanical Engineering Yanshan University state Key Laboratory of Metastable Materials Science and Technology Yanshan University

The effect of rare earth（RE） on Mo partitioning and resultant mechanical and microstructural behavior of a duplex stainless steel during hot working condition was investigated. It was found that RE effect was sensitive to temperature. At the high temperature, the development of dynamic recovery（DRV） in α phase was slowed down while the dynamic recrystallization（DRX） process in γ phase was accelerated by RE, whereby both work hardening rate（at low strain） and dynamic softening rate（at high strain） increased and moreover, the discrepancy on the hardness of the both phase reduced. Whereas at the low temperature, the effect of RE was opposite as compared with those in the high temperature. Mo partitioning analysis by EPMA indicated that RE enhanced the partitioning of Mo in α phase while reduced Mo concentration in γ phase at higher temperature whereby the mismatch between two phases could be improved indicated by the elimination of voids and cracks at α/γ interface, but it was contrary to that at the low temperature. Mo partitioning was believed to be an important cause for the RE effect on the differences of mechanical and microstructural behavior. Also this result provided a reasonable evidence for micro-alloying of RE in DSSs.

关键词： duplex stainless steel rare earths partitioning hot working