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不同采集方式与贮藏条件对“砀山酥梨”花粉活力的影响

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北方园艺 2015年第22期 44-47页

作者：郭媛宋怀磊邵有全山西省农业科学院园艺研究所山西太原030031

为了提高梨授粉过程中花粉采集的效率及贮藏效果,以＂砀山酥梨＂为试材,研究了蜜蜂采集和人工采集的梨花粉在-18、4℃和室温见光、室温避光的条件下贮藏不同时间的花粉活性。结果表明：-18℃较其它温度更利于花粉保存;人工采集的花粉活... 详细信息

为了提高梨授粉过程中花粉采集的效率及贮藏效果,以＂砀山酥梨＂为试材,研究了蜜蜂采集和人工采集的梨花粉在-18、4℃和室温见光、室温避光的条件下贮藏不同时间的花粉活性。结果表明：-18℃较其它温度更利于花粉保存;人工采集的花粉活性高于蜜蜂采集的花粉,蜜蜂采集的花粉-18℃保存15-20d可以保持较高活性,从而完成授粉。

关键词：梨蜜蜂采集人工采集花粉活性贮藏温度

Topologically Correct Intersection Curves of Two Trimmed Quadrics with Tolerance Control

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Journal of Systems Science & Complexity 2024年第5期37卷 2207-2239页

作者： shao Wenbing CHEN Falai Department of Mathematics University of Science and Technology of ChinaHefei 230026China

Surface/surface intersection is a fundamental problem in Compute Aided Design and Geometric Modeling since it is essential to solid modeling,numerically controlled machining,feature recognition,computer animation,*** practical applications,quadric surfaces,which are the most basic type of surfaces,are typically bounded surfaces trimmed by a sequence of *** this paper,a robust algorithm is proposed for computing the intersection curve segments of two trimmed quadrics based on the parametric representation of the intersection curves of two *** proposed algorithm guarantees correct topology and ensures that the approximation errors of the end points of the intersection curve segments are less than a given *** error control is based on an effective solution to a set of polynomial inequality system using the root isolation *** examples are presented to validate the robustness and effectiveness of the proposed algorithm.

关键词： Polynomial inequality system root isolation surface/surface intersection tolerance control trimmed quadrics

Pseudoeffective thresholds and cohomology of twisted symmetric tensor fields on irreducible Hermitian symmetric spaces

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Science China Mathematics 2024年第11期67卷 2433-2452页

作者： Feng shao Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

Let X be an irreducible Hermitian symmetric space of compact type(IHSS for short).In this paper,we give the irreducible decomposition of *** a by-product,we give a cohomological characterization of the rank of ***,we introduce pseudoeffective thresholds to measure the bigness of tangent bundles of smooth complex projective varieties precisely and calculate them for irreducible Hermitian symmetric spaces of compact type.

关键词： tangent bundle pseudoeffective threshold irreducible Hermitian symmetric space of compact type (IHSS) multiplicity free action

Homogeneous void nucleation in the presence of supersaturated vacancies and interstitials

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Journal of Materiomics 2024年第5期10卷 1147-1159页

作者： Lin shao Accelerator Laboratory Department of Nuclear EngineeringTexas A&M UniversityCollege StationTX77843USA

Homogeneous void nucleation in metals containing arbitrary vacancies and interstitials has been reexamined,with corrections made to the original work by Katz and *** void size distributions derived previously missed an exponential modification function with void size as the *** a result,void nucleation under a given vacancy supersaturation ratio is underestimated by orders of *** second improvement arises from the accuracy in calculating the vacancy arrival rate to a *** present work proposes establishing a direct relationship between the vacancy arrival rate and the available self-diffusion *** these corrections and improvements,void nucleation in pure Fe is calculated as an example,and an analytic fitting formula is *** required vacancy supersaturation ratio and interstitial-to-vacancy flux ratio for void nucleation calculations can be easily obtained from an analytical solution of rate theory calculations,in which dislocation density and displacements per atom(dpa)rate are adjustable ***,the nucleation rate calculation can be incorporated into rate theory calculations considering evolving dislocation densities,which leads to time-dependent void nucleation.

关键词： Void nucleation Voids Irradiation Swelling Defects

Analysis of spatial distribution characteristics and driving factors of ethnicminority villages in China using geospatial technology and statistical models

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Journal of Mountain Science 2024年第8期21卷 2770-2789页

作者： shao Dandan ZOH Kyungjin Interdisciplinary Program in Landscape Architecture Graduate School of Environmental StudiesSeoul National UniversitySeoul 08826Korea Graduate School of Environmental Studies Seoul National UniversitySeoul 08826Korea

This study aims to reveal the spatial structural characteristics of 1,652 Ethnic-Minority Villages(EMV)in China and to analyze the mechanisms driving their spatial *** are a special type of settlement space that preserve a large number of historical traces of the ethnic culture of ancient *** are important carriers of China’s excellent traditional culture and are key to the implementation of rural revitalization *** this study,1652 EMV in China were selected as the research *** Nearest Neighbor Index,kernel density,and spatial autocorrelation index were employed to reveal the spatial structural characteristics of minority *** network models,spatial lag models,and geographical detectors were used to analyze the formation mechanism of spatial heterogeneity in *** results indicate that:(1)EMV exhibit significant spatial differentiation characterized by“single-core with multiple surrounding sub-centers,”“polarization between east and west,”“decreasing quantity from southwest to east coast to northeast to northwest,”and“large dispersion with small agglomeration.”(2)EMV are mainly distributed in areas rich in intangible cultural heritage,with high vegetation coverage and low altitude,far from central cities,and having limited arable land and an underdeveloped economy and transportation,particularly in shaded or riverbank areas.(3)Distance from the nearest river(X3),distance from central cities(X8),national intangible cultural heritage(X9),and NDVI(X10)were the main driving factors affecting the spatial distribution of EMV,whereas elevation(X1)and GDP(X5)had the weakest *** EMV are a relatively unique territorial spatial unit,the identification of their spatial heterogeneity characteristics not only deepens the research content of settlement geography,but also involves the assessment,protection,and development of Minority Villages,which is of great significance for the inheritance and utilization of excellent

关键词： Ethnic-Minority Villages Spatial structure Settlement geography Neural network model Spatial econometric model GeoDetector

The bumblebees of North China（Apidae,Bombus Latreille）

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The bumblebees of North China（Apidae,Bombus Latreille）

Fear and delay effects on a food chain system with two kinds of different functional responses

二十一世纪第二届全国蜂业科技与蜂产业发展大会

作者：安建东 JIAXING HUANG youquan shao SHIWEN ZHANG BIAO WANG XINYU LIU JIE WU PAUL H.WILLIAMS Key Laboratory for Insect-Pollinator Biology of the Ministry of Agriculture Institute of ApicultureChinese Academy of Agricultural Sciences Institute of Horticulture Shanxi Academy of Agricultural Sciences Gansu Institute of Apiculture Ningxia Guyuan Apicultural Experiment Station Department of Life Sciences The Natural History Museum

Bumblebees are important pollinators for wild flowers and agricultural *** China is a region of varied geomor-phology and vegetation,with plateaus,plains,mountains and deserts,and is part of the greatest hotspot of bumblebee diversity *** report on a field survey of the bumblebees of North China made between 2005-2012.A sample of 21,636 bumblebee specimens are assigned to 76 *** older specimen held in London added one more species to this ***,these 77 species represent 10 subgenera of the genus *** species are recorded from North China for the first time:B.（St.） distinguendus,B.（Th.） anachoreta,B.（Th.） pseudobaicalensis,B.（Th.） exil,B.（Ps.） campestris,B.（Pr.） infirmus and B.（Ag.）*** provide identification keys for both males and females,photographs of the common colour patterns,and distribution maps for all *** describe variation in local species richness and abundance,and list the food plants used by bumblebees in North *** most abundant 10 bumblebee species are:B.（Ml.）pyrosoma,B.（Bo.） lantschouensis,B.（Bo.） patagiatus,B.（St.） melanurus,B.（Sb.） sibiricus,B.（Bo.） ignitus,B.（Th.） hedini,B.（Pr.） picipes,B.（Mg.） trifasciatus and B.（Mg.） *** are distributed widely within North China,from low elevations near the edge of the North-China plain to high elevations at the edge of the east Qinghai-Tibetan plateau（65-4011 m）.The highest species richness is found in meadows of the high elevation east Qinghai-Tibetan plateau and in forests of the Qilianshan mountains in southwestern ***337 food plant species recorded here belong to 49 families,showing that bumblebees play an important role in interconnecting agricultural and natural ecosystems in North China.

关键词： fauna biogeography distribution richness abundance pollinator food plants key to species

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International Journal of Biomathematics 2024年第3期17卷 89-122页

作者： Yuanfu shao College of Science Guilin University of Technology GuilinGuangci 541004P.R.China

For food chain system with three populations,direct predation is the basic interaction between *** species often have different predation functional responses,so a food chain system with Holling-II response for middle predator and Beddinton-DeAngelis response for top predator is *** from direct predation,predator population can significantly impact the survival of prey population by inducing the prey's fear,but the impact often possesses a time *** paper is concentrated to explore how the fear and time delay affect the system stability and the species *** use of Lyapunov functional method and bifurcation theory,the positiveness and boundedness of solutions,local and global behavior of species,the system stability around the equilibrium states and various kinds of bifurcation are ***,some simulations are carried out to validate the main findings and the critical values of the bifurcation parameters of fear and conversion rate are *** is observed that fear and delay can not only stabilize,but also destabilize the system,which depends on the magnitude of the fear and *** system varies from unstable to stable due to the continuous increase of the prey's fear by middle *** fear induced by top predator or small delay of the prey's fear can stabilize the system,while they are sufficiently large,the system stability is to be ***,the conversion rate can also change the stability and even make the species to be *** rich dynamics like multiple stabilities and various types of bistability behaviors are also exhibited,which results in the convergence of the species from one stable equilibrium to another.

关键词： Fear functional response equilibrium bifurcation analysis bi-stability

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梨花粉和柱头发育与温度关系研究

中国生态农业学报 2014年第12期22卷 1446-1452页

作者：郭媛邵有全郭宝贝张旭凤山西省农业科学院园艺研究所太原030031 山西省晋中种蜂场晋中030600

考察环境温度对梨花发育的影响是引进蜜蜂为梨树授粉的前提。本研究以主栽品种‘砀山酥梨’及其授粉品种‘鸭梨’为试验材料,设置了8℃、12℃、20℃3种温度条件,考察‘砀山酥梨’开花动态、柱头可授性及‘鸭梨’散粉、花粉萌发、花粉管... 详细信息

考察环境温度对梨花发育的影响是引进蜜蜂为梨树授粉的前提。本研究以主栽品种‘砀山酥梨’及其授粉品种‘鸭梨’为试验材料,设置了8℃、12℃、20℃3种温度条件,考察‘砀山酥梨’开花动态、柱头可授性及‘鸭梨’散粉、花粉萌发、花粉管生长等指标,旨在为梨树合理利用蜜蜂授粉提供理论依据。结果表明:在8℃下,‘砀山酥梨’花朵全部开放所需时间达到144 h以上,柱头具有较强可授性出现时间为112 h,且可授期持续时间短,‘鸭梨’全部散粉时间为230 h,花粉萌发率显著低于20℃(P<0.05),培养96 h到达花柱上部、中部、基部的花粉管数量分别为84根、55根、43根;12℃下,花朵全部开放时间为114 h,柱头出现较强可授性时间为88 h之后,‘鸭梨’全部散粉时间为158 h,花粉萌发速度较8℃快,但萌发率显著低于20℃(P<0.05),培养96 h到达花柱上部、中部、基部的花粉管数量分别为111根、105根、92根;20℃时,‘砀山酥梨’开花所需时间为44 h,柱头可授性强,且可授期持续时间可达120 h,‘鸭梨’全部散粉所需时间为64 h,花粉萌发速度快,萌发率高,培养96 h到达花柱上部、中部、基部的花粉管数量分别为121根、120根、119根。20℃较12℃和8℃更适合梨花发育和蜜蜂采集。本试验结果为不同温度下梨花的开花生物学特性研究提供了科学依据,也为梨树蜜蜂授粉技术的应用奠定了基础。

关键词：砀山酥梨鸭梨蜜蜂授粉柱头可授性花粉萌发花粉管生长温度

Layered double hydroxides functionalization toward rechargeable batteries Author links open overlay panel

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Particuology 2024年第8期91卷 138-154页

作者： Jianxiong Gao Bowen Jin Mingfei shao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China Renewable Energy Research Institute Quzhou Institute for Innovation in Resource Chemical EngineeringQuzhou324000China

Layered double hydroxides(LDHs),known as typical two-dimensional materials with unique physicochemical properties,are regarded as promising candidates in energy storage ***,some inherent defects,such as poor conductivity and limited active sites,hinder the further development of ***,various functionalization strategies(e.g.,intercalation of guest molecules;metal ions doping and defect introduction of host layer;exfoliation to monolayer;hybridization with functional materials;construction of hierarchical structure;interface engineering and phase transformation)have been used to modify the characteristics of LDHs,which provides guidance for designing novel *** this review,we discuss how these strategies improve the properties of LDH-based materials,which are expected to possess high electronic and ionic conductivity,high specific surface area and high mechanical and chemical stability ***,the application of LDH-based materials in advanced energy conversion and storage techniques,including metal-ions batteries,lithium-sulfur batteries and metal-air batteries,have been comprehensively summarized.

关键词： Layered double hydroxide Functionalization strategy Rechargeable battery