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Challenges and opportunities in Quaternary palynology

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Science china Earth sciences 2024年第7期67卷 2148-2161页

作者： Qinghai XU Houyuan lu Zhuo ZHENG College of Geographical sciences Hebei Key Laboratory of Environmental Change and Ecological ConstructionHebei Normal UniversityShijiazhuang 050024China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China school of Earth sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China

Quaternary palynology plays a pivotal role in investigating global climate change and various other research fields,serving as an essential tool for the quantitative analysis of paleoenvironment ***,due to the vast diversity of terrestrial ecosystems and intricate interactions between vegetation,climate,and human activities,further advancements are required in the following aspects within this discipline.(1)The accuracy of classification in pollen morphology and fossil pollen identification needs improvement,particularly at the species *** represents a significant challenge in present Quaternary ***-aided intelligent recognition holds promise as a solution for species identification based on more detail pollen morphology.(2)Most pollen-based vegetation and climate reconstructions overlook the significance of bare *** bare ground can lead to substantial inaccuracies when quantitatively reconstructing past vegetation and climate.(3.While pollen records provide reliable information on paleoclimate changes,current quantitative climate reconstruction models heavily rely on modern pollen datasets derived from present-day vegetation disturbed more or less by human *** introduces bias and uncertainties into paleoclimate reconstruction.(4.Although pollen can serve as an indicator of human activities,accurately quantifying the intensity of human influence remains *** accurate identification of crop pollen,reconstructing reliable land cover/use data,and integrating multidisciplinary data may enhance the identification and quantification of signals related to human activity in pollen records.

关键词： Quaternary palynology Paleoclimate Paleovegetation Human activity

Distribution and germination of viable diatom resting stage cells in sediments of the East china Sea

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Acta Oceanologica Sinica 2010年第5期29卷 121-128页

作者： ZHANG Yuyu lu Songhui ZHANG Chuansong GAO Yahui Key Laboratory of Ministry of Education for Coast and Wetland Ecosystems School of Life Sciences Xiamen University Xiamen 361005 China Research Center for Harmful Algae and Aquatic Environment Jinan University Guangzhou 510632 China College of Life Science South China Normal University Guangzhou 510631 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

The abundance and temporal patterns of viable diatom resting stage cells in sediments of the East china Sea in 2006 have been *** abundance of viable resting stages was enumerated with the most probable number（MPN） ***,25 diatom species（including varieties） belonging to 16 genera were *** resting stage cells were common,on the order of 103.to 106 cells/g dry *** abundant taxa included Skeletonema marina,***,Chaetoceros curvisetus and Thalassiosira spp.,with Skeletonema accounting for 83.3. of the *** effects of temperature（10,15,20,25 ℃）,salinity（20,25,3.,3. psu） and light intensity（0,3.0,4.000,8 000 lux） on the germination of resting stages in sediment samples were also *** results showed that light intensity had a significant positive effect on the germination of diatom resting stage cells（p 〈0.01） and that diatoms could not germinate in *** and salinity had no noticeable effects on the *** present study suggests that there are abundant diatom resting cells in sediments of the East china Sea,which could serve as a ＂seed bank＂ in the phytoplankton population succession and contribute to the initiation of algal blooms.

关键词： diatom germination MPN resting stages seed bank sediment

On the Modular Version of the Gluck-Wolf Theorem

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Acta Mathematica Sinica,English Series 2002年第2期18卷 335-338页

作者： lu Zi Qun school of mathematical {3..Peking University.Beijing 100871.P.R.{4. E-mail:zqlu@*** school of mathematical sciences Peking University Beijing P.R. China

Let N be a normal subgroup of a finite group *** be an irreducible Brauer character of *** π is a set of primes and (1)/(1)is a π'-number for any. X ∈IBr_p(G|).If p|G:N|, and N is p-solvable,then G/N has an abelia... 详细信息

关键词： ρ-Brauer character Lifting Brauer character ρ-length

A MACRO-SCALE SEMI-DISTRIBUTED HYDROLOGICAL MODEL AND APPLICATION TO THE DATONG RIVER VALLEY

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Journal of Hydrodynamics 2005年第6期17卷 667-676页

作者： YANG Zhi-feng LIU lu-liu SHEN Zhen-yao GORDON G. Huang State Key Laboratory of Water Environmental Simulation School of Environment Beijing Normal Uni- versity Beijing 100875 China National Climate Center Beijing 100081 China Faculty of Engineering University of Regina Canada

A daily distributed hydrological model was developed using routine hydro meteorological data on the basis of the raster DEM and land cover data. Then the model was used to model daily runoff of the Datong River Valley located in the upper catchment of the Yellow River Basin. The runoff comprises surface flow, subsurface flow and ground water flow. Evapotranspiration comprises canopy evaporation, snow sublimation and soil evapotranspiration. The infiltration to the soil was estimated with improved Green-Ampt model, and the potential evapotranspiration is estimated with Morton CRAE method, which only needs the routine meteorological data. Simulation results and the comparison with semi distributed SluRP hydrological model show that the structure of the model presented herein is reasonable.

关键词： hydrological model Yellow River GIS runoff

Divalent anion intercalation and etching-hydrolysis strategies to construct ultra-stable electrodes for seawater splitting

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Science china Chemistry 2024年第2期67卷 687-695页

作者： Jiajia lu Yang Liu Han-Pu Liang Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao266101China Henan Provincial Key Laboratory of Nanocomposites and Applications Institute of Nano-Structured Functional MaterialsHuanghe Science and Technology CollegeZhengzhou450006China school of Materials Science and Engineering Henan Normal UniversityXinxiang453007China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Shandong Energy Institute Qingdao266101China

Developing stable electrodes for seawater splitting remains a great challenge due to the detachment of catalysts at a large operating current and severe anode corrosion caused by ***,divalent anion intercalation and etching-hydrolysis strategies are deployed to synthesize the ultra-stable anode,dendritic Fe(OH)_(3. grown on Ni(SO_4._(0.3.(OH)_(1.4.–Ni(OH)_(2).Experimental results reveal that the anode exhibits good activity and excellent stability in alkaline simulated *** 500 h,the current density operated at 1.72 V remains 99.5%,about 210 m A cm^(-2).The outstanding stability originates from the etchinghydrolysis strategy,which strengthens the interaction between the catalyst and the carrier and retards thus the detachment of catalysts at a large current ***,theoretical simulations confirm that the intercalated divalent anions,such as SO_4.(2-) and CO_(3.^(2-),can weaken the adsorption strength of chlorine on the surface of catalysts and hinder the coupling and hybridization between chlorine and nickel,which slows down the anode corrosion and improves catalytic ***,the twoelectrode system shows the remarkable 95.1% energy efficiency at 2,000 A m-2and outstanding stability in 6 mol L^(-1) KOH +seawater at 80 ℃.

关键词： seawater splitting stability divalent anion intercalation etching-hydrolysis

Some Characterizations of Weighted Herz-type Hardy Spaces and Their Applications

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Acta Mathematica Sinica,English Series 1997年第1期13卷 45-58页

作者： lu shanzhen (Department of Mathematics,Beijing normal University,Beijing,{3.,{4.)(E-mail:lusz@***)Yang Dachun (Department of Mathematics,Beijing normal University,Beijin9,{3.,{4.)(E-mail:dcyang@***) Department of Mathematics Beijing Normal University 100875 Beijing China

In this paper,the authors first establish some new real-variable characterizations of Herz- type Hardy spaces Hqα,p（ω1;ω2）and HKqα,P（ω1;ω2）,where ω1,ω2 ∈A1-weight,1 详细信息

In this paper,the authors first establish some new real-variable characterizations of Herz- type Hardy spaces Hqα,p（ω1;ω2）and HKqα,P（ω1;ω2）,where ω1,ω2 ∈A1-weight,1

关键词： Herz space Herz-type Hardy space Potential operator

Conjectures and problems on Bochner-Riesz means

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Frontiers of Mathematics in china 2013年第6期8卷 1237-1251页

作者： shanzhen lu school of mathematical sciences Beijing Normal University Beijing 100875 China

The aim of this paper is to state some conjectures and problems on Bochner-Riesz means in multiple Fourier series and integrals. The progress on these conjectures and problems are also mentioned.

关键词： Bochner-Riesz means Fourier series Fourier integral norm convergence almost everywhere convergence

Spatiotemporal pattern of climate change in the china-Myanmar Economic Corridor from 1901 to 2018

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Journal of Mountain Science 2024年第1期21卷 131-145页

作者： YANG Xiaoliu LI Yungang GAO lu Institute of Geography Fujian Normal UniversityFuzhou 350117China school of Geographical sciences Fujian Normal UniversityFuzhou 350117China Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Fujian Provincial Engineering Research Center for Monitoring and Accessing Terrestrial Disasters Fujian Normal UniversityFuzhou 350117China Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350117China

The china-Myanmar Economic Corridor(CMEC) is an important part of china's Belt and Road Initiative and an important area for global ecology and biodiversity. In this study, the annual and seasonal spatiotemporal patterns of temperature and precipitation in the CMEC over the past century were investigated using linear tendency estimation, the Mann-Kendall mutation test, the T-test, and wavelet analysis based on the monthly mean climatic data from 1901 to 2018 released by the Climatic Research Unit(CRU) of the University of East Anglia, UK. The results show that the CMEC demonstrated a trend of warming and drying over the past 100 years, and the rate of change in Myanmar was stronger than that in Yunnan Province of china. The warming rate was 0.03. ℃/10a. Precipitation decreased at a rate of -6.1 mm/10a. From the perspective of spatial distribution, temperature was high in the central and southern, low in the north of the CMEC, and the high-temperature centers were mainly distributed in the southern plain and river valley. Precipitation decreased from west to east and from south to north of the CMEC. From the perspective of the rate of change, warming was stronger in central and northern CMEC than in southern and northeastern CMEC. The rate of precipitation decline was stronger in the central and western regions than in the eastern region. This study provides a scientific reference for the CMEC to address climate change and ensure sustainable social and economic development and ecological security.

关键词： china-Myanmar Economic Corridor CRU Air temperature Precipitation Spatiotemporal pattern

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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Science china Chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2,ZHONG QingDong2 & lu TianHong3.1Department of Chemical Engineering,Shanghai Institute of Technology,Shanghai 20023.,china 2{4. of Materials Science and Engineering,Shanghai University,Shanghai 200072,china 3.epartment of Chemistry,Nanjing normal University,Nanjing 210097,china 1. Department of Chemical Engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPS that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.73. × 10-12 mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry