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Structure and Electrical Characteristics of Zinc Oxide Thin Films Grown on Si (111) by Metal-organic Chemical Vapor Deposition

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Journal of Materials Science & Technology 2013年第9期29卷 830-834页

作者： Yunfeng Wu dongping liu Naisen Yu Yuanda liu Hongwei Liang Guotong Du School of Physics and Optoelectronic Technology Dalian University of Technology School of Physics and Materials Engineering Dalian Nationalities University

ZnO thin films were grown on Si （111） substrates by low-pressure metal-organic chemical vapor deposition. The crystal structures and electrical properties of as-grown sample were investigated by scanning electron microscopy （SEM） and conductive atomic force microscopy （C-AFM）. It can be seen that with increasing growth temperature, the surface morphology of ZnO thin films changed from flake-like to cobblestones-like structure. The current maps were simultaneously recorded with the topography, which was gained by C-AFM contact mode. Conductivity for the off-axis facet planes presented on ZnO grains enhanced. Measurement results indicate that the off-axis facet planes were more electrically active than the c-plane of ZnO flakes or particles probably due to lower Schottky barrier height of the off-axis facet planes.

关键词： ZnO thin films Metal-organic chemical vapor deposition Conductive atomic force microscopy Scanning electron microscopy

Optimization of Land Use Structure Based on Ecological GREEN Equivalent

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Geo-Spatial Information Science 2002年第4期5卷 60-67页

作者： liu Yanfang MING dongping YANG Jianyu School of Resource and Environment Science Wuhan University Wuhan China

Optimization of land use structure consists of economic and social and ecological *** the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district;through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland)and based on the rule,GREEN equivalent,this paper introduces the area conversion between woodland and cultivated land,also between woodland and grassland;this paper establishes a multi_dimension controlling model of optimization of land use *** addition,a multi_objective linear programming model for optimization of land use structure is *** the end,this paper tests and verifies this theory of ecological optimization,taking Qionghai city in Hainan Province as an example.

关键词： land use structure forest_coverage rate GREEN equivalent value of ecosystem services multi_dimension optimization multi_objective linear programming

Population dynamics and habitat use of the Black-necked Crane (Grus nigricollis) in the Yarlung Tsangpo River basin, Tibet, China

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Avian Research 2019年第3期10卷 366-373页

作者： Ru Jia Tian Ma Fengjiang Zhang Guogang Zhang dongping liu Jun Lu Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091China Key Laboratory of Forest Protection of State Forestry and Grassland Administration Beijing 100091China National Bird Banding Center of China Beijing 100091China Wildlife Conservation and Disease Surveillance Center of Liaoning Province Dalian 116000China

Background:The Black-necked Crane (Grus nigricollis)is an internationally threatened crane living on the plateau, mainly in winter, in the Yarlung Tsangpo River basin in Tibet,western China. In the past five years,some economic development projects have been conducted in this area,posing potential threats to the wintering populations of the cranes and their habitats. Therefore, the current population dynamics of wintering Black-necked Cranes and habitat suitability in the Yarlung Tsangpo River basin were investigated. Methods: Twenty counties were surveyed using the line transect method in December 2017 and January 2018, and we recorded the location,flock size,number of individuals,habitat types and presence of human disturbance in which they *** compared the results from the middle wintering period in this survey with those from 2014. Results: The highest number of cranes recorded was 8291,and the results showed that the cranes were mainly distributed in Lhaze, Namling, Samzhubze, and Lhunzub.A total of 577 and 495 flocks were recorded in the early and middle wintering periods, respectively. In the early wintering period,there were signi ficant differences in the number of individuals across the di fferent habitats,with crop stubble land and plowed land representing more than 30% of the total habitat *** the middle wintering period, there were also signi ficant differences in the number of individuals, and the utilization of crop stubble land represented over 60% of the total. Conclusions: Wintering Black-necked Cranes mainly fed on spilled grains in stubble habitat after harvest. In the middle wintering period, some of the farmlands were plowed and irrigated,which resulted in food shortages in these areas,and the cranes tended to gather in mixed flocks of large size instead of as a single *** were still considerable regional wintering populations decreases in Quxu,Nedong,and Sakya in 2018 compared with 2014,and these decreases were main

关键词： Black-necked Crane Habitat use Population dynamics Tibet Yarlung Tsangpo River basin

A revised species population estimate for the Bar-headed Goose(Anser indicus)

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Chinese Birds 2017年第1期8卷 57-62页

作者： dongping liu Guogang Zhang Fengshan Li Tian Ma Jun Lu Fawen Qian KeyLaboratoryofForestProtectionofStateForestryAdministration ResearchInstituteofForestEcologyandEnvironmentProtectionChineseAcademyofForestry InternationalCraneFoundation

Background: The Bar-headed Goose(Anser indicus) is a species that relies heavily on the plateau wetlands of Asia and whose population was thought to be declining. Over the past decade, south-central Tibet, one of the most important wintering grounds, supported large numbers of Bar-headed Geese, but the population had not been regularly monitored in this ***: We surveyed wintering Bar-headed Geese along the Yarlung Zangbo, Lhasa and Nyang Qu rivers, the three major river valleys and their tributaries in south-central Tibet in January 2014 and recorded their location, flock size and habitat utilization. Based on these data and the latest wintering counts elsewhere, we revised the population estimate for this ***: We recorded more than 67,000 Bar-headed Geese in south-central Tibet during January 2014. By geographic area, the geese were most abundant in the Lhasa River valley(38.5%) and the Nyang Qu River valley(31.0%), and by administrative division in Lhunzhub(27.2%) and Shigatse(26.7%). Bar-headed Geese were most often observed feeding in winter wheat fields and ploughed fields, resting on pastureland and marshes. The approximate number of 67,000 geese recorded in Tibet is more than four times the estimate of 1993 for the same region and exceeds the most recent world population estimate of 52,000–60,000. Based on our work in Tibet and the latest wintering counts available from other areas, we revised the estimated population size of this species to 97,000–118,***: Our result reveals a remarkable increase in the number of Bar-headed Geese wintering in south-central Tibet. This population increase most likely stems from a proliferation of cropland and especially winter wheat fields in south-central Tibet. This habitat improvement may also cause short-stopping of the Bar-headed Goose and thus reduce mortality of the geese that would otherwise undertake a somewhat daunting trans-Himalayan migration.

关键词： Bar-headed Goose Species population estimate Tibet Wintering ground

Migration routes of the endangered Oriental Stork(Ciconia boyciana)from Xingkai Lake,China,and their repeatability as revealed by GPS tracking

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Avian Research 2023年第2期14卷 215-222页

作者： Zeyu Yang Lixia Chen Ru Jia Hongying Xu Yihua Wang Xuelei Wei dongping liu Huajin liu Yulin liu Peiyu Yang Guogang Zhang Key Laboratory of Forest Protection of National Forestry and Grassland Administration National Bird Banding Center of ChinaEcology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China Xingkai Lake National Nature Reserve of Heilongjiang JixiHeilongjiang158300China

The Oriental Stork(Ciconia boyciana)is listed as'Endangered'on the International Union for the Conservation of Nature(IUCN)Red List of Threatened Species and is classified as a first category nationally protected bird species in *** this species'seasonal movements and migration will facilitate effective conservation to promote its *** tagged 27 Oriental Stork nestlings at Xingkai Lake on the Sanjiang Plain in Heilongjiang Province,China,used GPS tracking to follow them over the periods of 2014-2017 and 2019-2022,and confirmed their detailed migratory routes using the spatial analysis function of ArcGIS *** discovered four migration routes during autumn migration:one common long-distance migration route in which the storks migrated along the coastline of Bohai Bay to the middle and lower reaches of the Yangtze River for wintering,one short-distance migration route in which the storks wintered in Bohai Bay and two other migration routes in which the storks crossed the Bohai Strait around the Yellow River and wintered in South *** were no significant differences in the number of migration days,residence days,migration distances,number of stopovers and average number of days spent at stopover sites between the autumn and spring migrations(P>0.05).However,the storks migrated significantly faster in spring than in autumn(P=0.03).The same individuals did not exhibit a high degree of repetition in their migration timing and route selection in either autumn or spring *** storks from the same nest exhibited considerable between-individual variation in their migration *** important stopover sites were identified,especially in the Bohai Rim Region and on the Songnen Plain,and we further explored the current conservation status at these two important ***,our results contribute to the understanding of the annual migration,dispersal and protection status of the endangered Oriental Stork and provide a scientific bas

关键词： Autumn migration GPS tracking Oriental stork Repeatability Spring migration Stopover site

Autumn migration routes of fledgling Chinese Egrets(Egretta eulophotes)in Northeast China and their implications for conservation

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Avian Research 2022年第1期13卷 78-86页

作者： Hongying Xu Zeyu Yang dongping liu Ru Jia Lixia Chen Boshi Liang Zhengwang Zhang Guogang Zhang Ecology and Nature Conservation Institute Chinese Academy of ForestryBeijing100091China Key Laboratory of Forest Protection of National Forestry and Grassland Administration Beijing100091China National Bird Banding Center of China Beijing100091China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China

The Chinese Egret(Egretta eulophotes)is a globally threatened bird species living on the coast and islands of Liaoning,northeastern China,mainly in *** further protect the breeding population of Chinese Egrets,it is important to understand the current protection status of their distribution sites at pre-migration period and migration ***-three individuals were tagged with satellite transmitters at Fantuo Island in Changhai and Xingren Island in Zhuanghe,Liaoning Province,northeastern China,in July of 2016,2017,and 2018,to identify important distribution sites during the pre-migration period,as well as detailed migration *** results showed that coastal mudflats in Liaoning and the west coast of North Korea were important feeding and roosting sites for fledgling Chinese Egrets from August to *** home range sizes in August were significantly larger than in *** eastern coast from Shandong to Guangdong,as well as Taiwan,China,and Manila Bay and Galileo Islands in the Philippines,were important stopover sites during fall ***,we found that the egrets’autumn migration could be divided into four routes,i.e.,sea-crossing migration(SCM),coastal migration(CM),inland migration(IM),and mixed migration(MM).The migration distance,timing,speed,and straightness of the four routes also *** SCM routes were the straightest,and had the fastest migration speed and shortest travel time,while the IM routes had the lowest straightness and speed,and the longest *** Bay and Bohol Island in the Philippines,the west coast of Tanintharyi in Myanmar,and the Zengwun River Estuary in Taiwan,China,were wintering *** findings on the key distribution sites along pre-migration and fall migration routes,including some stopover sites,have important implications for the conservation of and global action plan development for the vulnerable Chinese Egret.

关键词： Conservation implications Fledgling Chinese Egret Migration route Liaodong Peninsula Satellite tracking

Numerical study on an atmospheric pressure helium discharge propagating in a dielectric tube:influence of tube diameter

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Plasma Science and Technology 2018年第8期20卷 22-28页

作者： Zhoutao SUN Wen YAN Longfei JI Zhenhua BI Ying SONG dongping liu School of Physics and Materials Engineering Dalian Nationalities UniversityDalian 116600People＇s Republic of China

In this work, a two-dimensional numerical simulation of the discharge characteristics of helium plasma propagating inside a dielectric tube was performed. A trapezoidal ＋9 kV pulse lasting 400 ns was applied on a needle electrode set inside the dielectric tube to ignite the discharge. The discharges generated in the tubes with a variable or a constant inner diameter were *** focus of this study was on clarifying the effect of the tube diameter on the discharge structure and dynamics. The comparison of the discharge characteristics generated in dielectric tubes with different diameters was carried out. It was shown that the tube diameter plays a significant role in discharge behavior of plasma propagating in the dielectric tube.

关键词： atmospheric pressure helium discharges discharge front numerical simulation

Wenzhou Champion Heavyweight of the Light Industry

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China Today 2003年第3期52卷 65-67页

作者： liu dongping

CLUSTERS of garment,shoe and small commodi—ty retail stores inWenzhou,and the giantbillboards soaring above eachbuilding advertising shoes andcustom—made suits proclaim thecity’s thriving light *** likely topic of ... 详细信息

关键词：温州市轻工业制鞋业 WTO 贸易经济

Dynamics of ionisation wave propagation in an applied external electric field

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High Voltage 2016年第2期1卷 90-94页

作者： Yang Xia dongping liu Hamidreza Ghomi Wenchun Wang Zhenhua Bi Longfei Ji Xueyang Wang Zhihua Qi Bin Li Liaoning Key Laboratory of Optoelectronic Films and Materials School of Physics and Materials EngineeringDalian Nationalities UniversityDalian 116600People’s Republic of China School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024People’s Republic of China Laser and Plasma Research Institute Shahid Beheshti UniversityEvinTehran ***Iran Beijing Guangyao Energy Technology Co. LtdBeijing 100015People’s Republic of China

This study presents spatio-temporal development of the ionisation waves(IWs)along one dielectric tube with an extra alternating electric field.A pulsed direct current power supply is used for generating the IWs,and another alternating current power supply is used for altering the distribution of electric fields along the dielectric *** measurements show that the propagation velocity and density of IWs are strongly affected by the external electric *** direct relation between external electric field and the velocity of the IWs is *** analysis indicates that the external electric field can be utilised to control the propagation of the IWs,resulting in a change of their density and velocity.

关键词： field. propagation dielectric