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Vegetation NPP Distribution Based on MODIS Data and CASA Model——A Case Study of Northern Hebei Province

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Chinese Geographical Science 2006年第4期16卷 334-341页

作者： YUAN Jinguo niu zheng WANG Chenli State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Belting 100101 China College of Resource and Environmental Sciences Hebei Normal University Shifiazhuang 050016 China

Net Primary Productivity （NPP） is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and temporal distribution of CO2. Remote sensing can provide broad view quickly, timely and multi-temporally, which makes it an attractive and powerful tool for studying ecosystem primary productivity, at scales ranging from local to global. This paper aims to use Moderate Resolution Imaging Spectroradiometer （MODIS） data to estimate and analyze spatial and temporal distribution of NPP of the northern Hebei Province in 2001 based on Carnegie-Ames-Stanford Approach （CASA） model. The spatial distribution of Absorbed Photosynthetically Active Radiation （APAR） of vegetation and light use efficiency in three geographical subregions, that is, Bashang Plateau Region, Basin Region in the northwestern Hebei Province and Yanshan Mountainous Region in the Northern Hebei Province were analyzed, and total NPP spatial distribution of the study area in 2001 was discussed. Based on 16-day MODIS Fraction of Photosynthetically Active Radiation absorbed by vegetation （FPAR） product, 16-day composite NPP dynamics were calculated using CASA model; the seasonal dynamics of vegetation NPP in three subreglons were also analyzed. Result reveals that the total NPP of the study area in 2001 was 25.1877 × 10^6gC/（m^2.a）, and NPP in 2001 ranged from 2 to 608gC/（m^2-a）, with an average of 337.516gC/（m^2.a）. NPP of the study area in 2001 accumulated mainly from May to September （DOY 129-272）, high NIP values appeared from June to August （DOY 177-204）, and the maximum NPP appeared from late July to mid-August （DOY 209-224）.

关键词： NPP distribution MODIS data CASA model Northvrn Hebei Province

Stepwise decomposition and relative radiometric normalization for small footprint LiDAR waveform

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Science China Earth Sciences 2011年第4期54卷 625-630页

作者： QIN YuChu LI Bin niu zheng HUANG WenJiang WANG ChangYao State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

As an advanced generation instrument of earth observation,small footprint full waveform light detection and ranging(LiDAR) technology has been widely used in the past few *** and radiative correction is an important step in waveform data processing,it influences the accuracy of both information extraction and further *** on a stepwise strategy,this study adopts Gaussian mixture model to approximate the LiDAR *** addition to waveform decomposition,a relative correction model is proposed in this paper,the model considers the transmit pulses as well as the different of the travel path for implementing LiDAR waveform relative *** of the stepwise decomposition and relative correction model are carried out on LiDAR waveform acquired over Zhangye,*** results indicate that stepwise decomposition identified the number of peaks in LiDAR waveforms,center position and width of each peak *** relative radiometric correction also improves the similarity of waveforms which acquired at the same target.

关键词： LiDAR waveform Gaussian mixture model stepwise decomposition relative radiometric correction

Spatial-temporal variations of surface water area during 1986-2018 in Qinghai Province,northwestern China based on Google Earth Engine

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Big Earth Data 2024年第2期8卷 333-349页

作者： Luying Zhu Haifeng Tian Ni Huang Li Wang zheng niu State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina College of Geography and Environmental Science Henan UniversityKaifengChina

Called the“Water Tower”,the water resource in Qinghai Province plays a vital role in the ecological environment of northwestern ***,significant uncertainty exists regarding its spatialtemporal *** this study,the data on the surface water of Qinghai Province from 1986 to 2018 was extracted and a systemic analysis of its spatial-temporal variations and responses to climate change was conducted using the Google Earth Engine(GEE)cloud processing *** findings revealed that the surface water in Qinghai Province was primarily concentrated in the Qaidam Basin,the Hoh Xil Nature Reserve,and Qinghai *** surface water area in Qinghai Province exhibited an overall increasing trend,with the temperature and precipitation being the primary drivers of this *** results provide crucial insights into the variations of surface water variations in Qinghai Province,northwestern China,under the influence of climate change.

关键词： Qinghai Province Google Earth Engine surface water climate change

Identification of integrin β6 gene promoter and analysis of its transcription regulation in colon cancer cells

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World Journal of Gastrointestinal Oncology 2020年第5期12卷 526-534页

作者： Wei niu Qi-Yu Bo Jun niu zheng-Chuan niu Cheng Peng Xue-Qing Zou Zhao-Yang Zhang Department of Hepatobiliary Surgery Qilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina Department of Nursing Qilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina Department of Emergency Surgery Qilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND The integrinβ6 gene,which is expressed in epithelial cancer,plays a pivotal role in various aspects of cancer *** present research for integrinβ6 regulation mainly focuses on the post-transcription and translation related regulation mechanism and its role in *** mechanisms of how the integrinβ6 gene is regulated transcriptionally,and the promoter and transcription factors responsible for basic transcription of integrinβ6 gene remain *** To clone and characterize the integrinβ6 *** Software analysis was used to predict the region of integrinβ6 *** reporter plasmids,which contained the integrinβ6 promoter,were *** deletion analysis was performed to identify the location of core promoter and binding sites for transcription *** The regulatory elements for the transcription of the integrinβ6 gene were located between-286 and-85 and contained binding sites for transcription factors such as STAT3 and *** For the first time,we found the region ofβ6 core promoter and demonstrated the binding sites for transcription factors such as Ets-1 and STAT3,which are important for integrinβ6 promoter transcription *** findings are important for investigating the mechanism of integrinβ6 activation in cancer progression.

关键词： Integrinβ6 Integrinβ6 promoter Regulatory elements Transcription factors Colon cancer cell

Coordination Polymers with Bipyridyl Diene and Triene Ligands:Synthesis,Structures and Luminescent Properties

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Chemical Research in Chinese Universities 2022年第1期38卷 209-216页

作者： HUA Chen YI Pin LIU Wencong WANG Mengfan niu zheng LANG Jianping College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123P.R.China

Solvothermal reactions of cadmium salts with bipyridyl diene and triene ligands[1,3-bis((E)-2-(pyridin-4-yl)vinyl)benzene-(1,3-bpeb) and 1,6-bis(4-pyridyl)-1,3,5-hexatriene(bphte)] and one bipyridyl triene ligand[1,6-bis(4-pyridyl)-1,3,5-hexatriene-(bphte)] in the presence of auxiliary carboxylic acids including 2,6-dichlorobenzoic acid(2,6-HDCBA) and 2-naphthal-enecarboxylic acid(2-HNCA) gave rise to four coordination polymers[Cd(bphte)(2,6-DCBA)2]n(1), {[Cd(bphte)(2-NCA)2]·5.8H2O}n(2),[Cd2(1,3-bpeb)2(2,6-DCBA)4]n(3) and {[Cd4(1,3-bpeb)4(2-NCA)7(HCOO)]·2-HNCA·H2O}n(4), respectively. Compounds 1-4 were structurally characterized by elemental analysis, IR, 1H NMR, powder X-ray diffraction, thermogravimetric analysis and single-crystal X-ray diffraction. They possess one-dimensional linear(1, 2) and zigzag(3, 4) chain structures. Their luminescent properties were explored while the representative sample 4 exhibited good luminescent performance in sensing Fe(III) in water.

关键词： Coordination polymer Bipyridyl olefinic ligand Crystal structure Luminescent property

Land Degradation Evaluation in North Hebei Province Based on Remote Sensing and GIS

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Chinese Journal of Population,Resources and Environment 2006年第3期4卷 28-36页

作者： Yuan Jinguo Liu Jinsong Wang Wei niu zheng State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China College of Resources and Environmental Sciences Hebe[Normal University Shijiazhuang 050016 China

Land degradation is one of the serious environmental problems that can lead to poverty, and is especially prominent in eco-fragile areas in developing countries and increases the risk of environmental safety. North Hebei Province belongs to an ecologically fragile region in North China, which has great impact on the eco-safety of Beijing and Tianjin. Using Landsat TM data and GIS, this paper evaluates land degradation in North Hebei province of China from the the 1960′s to 1987 and 2000. Land use/cover change pattern from 1987 to 2000, its regional difference and forest change characteristics will also be analyzed; soil erosion intensity and arable land suitability were also evaluated. Results revealed that land use/cover pattern in this study area did not change greatly from 1987 to 2000. The structure and function of regional land ecosystem was at a level of local improvement and integral deterioration. Land above medium soil erosion intensity reached 21 percent, which was also the area with a serious soil erosion and land degradation problem. Soil erosion and land degradation intensity of grassland was the biggest. For the present arable land, the proportion of high suitability was 13 percent.

关键词： land degradation North Hebei Province soil erosion intensity arable land suitability evaluation

Influence of China’s Overseas power stations on the electricity status of their host countries

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International Journal of Digital Earth 2022年第1期15卷 416-436页

作者： Xumiao Gao Mingquan Wu Chao Li zheng niu Fang Chen Wenjiang Huang State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Jinan Geotechnical Investigation and Surveying Institute JinanPeople’s Republic of China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China

China has become a major investor and constructor of electrical power plants in developing ***,the impacts of China's overseas power stations(COPSs)on the developing countries hosting them are poorly ***,a novel method is proposed to evaluate the influence of COPSs in 80 host ***,their electricity consumption from 1971 to 2017 was estimated using data provided by the World Bank,International Energy Agency,and World Resources *** analysis was then used to predict consumption from 2018 to ***,three parameters were used to evaluate the influences of *** results show that:1)COPSs significantly increased the total installed capacity of 35 of the host countries by>20%.2)The power generated by COPSs is greater than the growing demands of 32 of the host countries.3)COPSs will increase the per capita electricity consumption of all 80 host countries.4)Among the 437 COPSs existing in 2000–2019,renewable power plants(including hydropower)were most numerous,accounting for 51.3%.This proportion increased significantly after 2013 and renewable plants will continue to dominate as China will no longer invest in new coal-fired power stations after 2021.

关键词： Influence of China’s overseas power stations Belt and Road Initiative electricity status renewable sources of energy SDG7

A microporous lanthanide metal-organic framework containing channels:Synthesis,structure,gas adsorption and magnetic properties

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Science China Chemistry 2011年第9期54卷 1423-1429页

作者： LI HuanHuan niu zheng HAN Tian ZHANG ZhenJie SHI Wei CHENG Peng Key Laboratory of Advanced Energy Materials Chemistry Ministry of Education(MOE)Department of ChemistryNankai UniversityTianjin 300071China

Under solvothermal condition,the reaction of furan-2,5-dicaboxylate(H2FDA) and glycol with Gd(NO3)3.6H2O gave microporous lanthanide metal-organic framework(MOF),{[Gd(FDA)1.5(glycol)].1.5H2O}}n(1).This compound was characterized by single crystal X-ray diffraction,infrared spectroscopy,elemental analysis,thermogravimetry analysis,and powder X-ray *** Gd(III) ions were connected by carboxylic group of FDA2-to give 1D chains,which were further linked by FDA2-,forming a 3D porous framework with 3D *** adsorption properties with N2,H2 and CO_(2) of the compound were *** studies show that there are weak ferromagnetic interactions transmitted by μ1,3 carboxylic group between the Gd(III) ions.

关键词： crystal structure MOFs channel magnetism gas absorption

Multiple structural defects in ultrathin NiFe-LDH nanosheets synergistically and remarkably boost water oxidation reaction

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Nano Research 2022年第1期15卷 310-316页

作者： Zhongyin Zhao Qi Shao Jiangyan Xue Bolong Huang zheng niu Hongwei Gu Xiaoqing Huang Jianping Lang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHung HornKowloonHong Kong SARChina

Modifying electrocatalysts nanostructures and tuning their electronic properties through defects-oriented synthetic strategies are:essential to improve the oxygen evolution reaction(OER)performance of *** synthetic strategies *** mainly target the single or double structural defects,while the researches about the synergistic effect of multiple'structural defects are *** this work,the ultrathin NiFe layered double hydroxide nanosheets with a holey structure,oxygen;vacancies and Ni^(3+)defects on nickel foam(NiFe-LDH-NSs/NF)are prepared by employing a simple and green H202-assisted etching 1 *** synergistic effect ofthe above three defects leads to the exposure *** active sites and significant improvement of:the intrinsic *** optimized catalyst exhibits an excellent OER performance with an extraordinarily low overpotential of 170 mV;at to mA·cm^(-2) and a small Tafel slope of 39.3 mV·dec^(-1) in 1 M KOH *** functional theory calculations reveal this OER;performance arises from pseudo re-oxidized metal-stable Ni^(3+)near oxygen vacancies(O_(vac)),which suppresses 3d-e_(g) of Ni-site and!elevates d-band center towards the competitively low *** work provides a new insight to fabricate advanced electrocatalysts for renewable energy conversion technologies.

关键词： layered double hydroxide holey structures oxygen vacancies Ni3+defects oxygen evolution reaction