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基于改进Reddy型三阶剪切变形理论的弹性地基上FG-CNTRC板屈曲无网格分析

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计算力学学报 2024年第3期41卷 572-581页

作者：许建文严世涛彭林欣陈卫广西新发展交通集团有限公司南宁530004 广西交通职业技术学院南宁530004 广西大学土木建筑工程学院南宁530004 南华大学土木工程学院衡阳421001

针对含碳纳米管转向的Pasternak地基上功能梯度碳纳米管增强复合材料FG-CNTRC(functionally graded carbon nanotube-reinforced composite)板的屈曲问题,提出了一种基于改进Reddy型三阶剪切变形理论TSDT(third-order shear deformation theory)和移动最小二乘近似MLS(moving-least square)的无网格分析模型。该模型避免了无网格法第二类边界条件的施加困难问题,且能够满足中厚/厚板的自由表面条件,无需额外引入剪切修正因子。基于最小势能原理推导了弹性地基上FG-CNTRC板的无网格屈曲控制方程,采用完全转换法处理本质边界条件。通过基准算例验证了本文方法的收敛性及有效性,讨论了碳纳米管的转向角、体积分数、分布形式、地基系数、宽厚比和边界条件等对FG-CNTRC板临界屈曲荷载的影响。

关键词：改进Reddy型三阶剪切变形理论功能梯度碳纳米管增强复合材料板 Pasternak地基临界屈曲荷载移动最小二乘近似

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基于SNP标记的小麦品种遗传相似度及其检测准确度分析

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作物学报 2024年第4期50卷 887-896页

作者：许乃银金石桥晋芳刘丽华徐剑文刘丰泽任雪贞孙全许栩庞斌双江苏省农业科学院经济作物研究所江苏南京210014 全国农业技术推广服务中心北京100125 北京市农林科学院杂交小麦研究所北京100097

遗传相似度检测的准确度估计是对SNP标记法在农作物品种检测体系中应用的必要补充和完善。本研究基于2021年小麦品种SNP标记法跨实验室协同验证实验数据,分析了该方法的检测准确度及在品种间的遗传相似度。分析结果表明:(1)10个实验室... 详细信息

遗传相似度检测的准确度估计是对SNP标记法在农作物品种检测体系中应用的必要补充和完善。本研究基于2021年小麦品种SNP标记法跨实验室协同验证实验数据,分析了该方法的检测准确度及在品种间的遗传相似度。分析结果表明:(1)10个实验室对55组小麦品种组合的标记位点相似度检测的总体准确度约为98%。(2)GGE双标图的品种遗传关系功能图显示,7组小麦品种的组内遗传相似度在95%以上,其余组合的遗传相似度较低。(3)依据GGE双标图的“正确度-精确度”功能图和“准确度排序”功能图,发现洛旱7号/洛旱11等品种组合的相似度检测准确度较高,晋麦47/临抗11的检测准确度一般,而济麦22/婴泊700的检测准确度较差。(4)10个实验室的检测准确度存在显著差异,其中2个实验室检测的正确度、精确度和准确度表现显著差于其余实验室。(5)各实验室检测正确度的容许误差分布于1.3%~1.9%之间,平均为1.5%;准确度的容许误差分布于1.5%~2.0%之间,平均为1.7%。其中,Lab2和Lab3的检测正确度和准确度的容许误差显著差于其余实验室。本研究构建了SNP标记法对品种相似性检测的准确度统计模型,分析了品种组合和实验室的检测准确度及其容许误差,采用GGE双标图方法对检测正确度、精确度和准确度进行可视化分析,验证了各实验室对品种位点相似性检测的准确度和可靠性,为SNP标记法在农作物品种遗传相似性检测中的准确度评价提供了理论支持和应用范例。

关键词：小麦(Triticum aestivum L.) GGE双标图 SNP标记遗传相似度位点相似度准确度

Spatiotemporal Characteristics of Reference Evapotranspiration and Its Sensitivity Coefficients to Climate Factors in Huang-Huai-Hai Plain,China

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Journal of Integrative Agriculture 2013年第12期12卷 2280-2291页

作者： YANG jian-ying LIU Qin MEI xu-rong YAN Chang-rong JU Hui xu jian-wen Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences State Engineering Laboratory of Efficient Water Use and Disaster Reduction for Crops Ministry of Agriculture Key Laboratory of Dryland Agriculture Ministry of Agriculture Key Laboratory of Agricultural Environment Ministry of Agriculture

Climate change will have important implications in water shore regions,such as Huang-Huai-Hai（3H） plain,where expected warmer and drier conditions might augment crop water *** analysis is important in understanding the relative importance of climatic variables to the variation in reference evapotranspiration（ET 0）.In this study,the 51-yr ET 0 during winter wheat and summer maize growing season were calculated from a data set of daily climate variables in 40 meteorological *** maps for key climate variables were estimated according to Kriging method and the spatial pattern of sensitivity coefficients for these key variables was *** addition,the slopes of the linear regression lines for sensitivity coefficients were *** showed that ET 0 during winter wheat growing season accounted for the largest proportion of annual ET 0,due to its long phenological days,while ET 0 was detected to decrease significantly with the magnitude of 0.5 mm yr-1in summer maize growing *** radiation is considered to be the most sensitive and primarily controlling variable for negative trend in ET 0 for summer maize season,and higher sensitive coefficient value of ET 0 to solar radiation and temperature were detected in east part and southwest part of 3H plain *** humidity was demonstrated as the most sensitive factor for ET 0 in winter wheat growing season and declining relativity humidity also primarily controlled a negative trend in ET 0,furthermore the sensitivity coefficient to relative humidity increased from west to *** eight sensitivity centrals were all found located in Shandong *** ET 0 along with its sensitivity maps under winter wheat-summer maize rotation system can be applied to predict the agricultural water demand and will assist water resources planning and management for this region.

关键词： ET 0 spatial distribution temporal trends sensitivity coefficient 3H plain

实现“双碳”目标的关键路径完善碳达峰与碳中和标准计量体系

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中国检验检测 2024年第4期32卷 3-6页

作者：陈岳飞黄怡璠徐文见湖南省计量检测研究院长沙410014 中国计量科学研究院北京100029

随着全球气候变化对环境与经济造成越来越大的影响,中国制定了“碳达峰、碳中和”战略,致力于通过全面减少碳排放,实现可持续发展目标。为了有效支持这一战略目标,构建和完善碳达峰与碳中和的标准计量体系成为重要任务。本文详细探讨了... 详细信息

随着全球气候变化对环境与经济造成越来越大的影响,中国制定了“碳达峰、碳中和”战略,致力于通过全面减少碳排放,实现可持续发展目标。为了有效支持这一战略目标,构建和完善碳达峰与碳中和的标准计量体系成为重要任务。本文详细探讨了夯实基础研究、推动技术创新、完善标准体系、实现数字化转型以及加强市场机制等关键领域,以实现高精度和广覆盖的碳计量系统。此外,文章也强调了通过国际合作和标准接轨,提升中国在全球碳市场中的竞争力和影响力。通过这些综合措施,可以确保碳达峰与碳中和目标的有效实施,为我国及全球的环境保护与气候治理做出贡献。

关键词：碳达峰碳中和标准计量体系碳计量技术创新国际合作

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棉花抗旱性综合评价及其相关性分析

江苏农业学报 2024年第1期40卷 1-13页

作者：王月平徐剑文赵君刘剑光王宁山程俊凌冯国礼艾尼江陈全家肖松华新疆农业大学农学院新疆乌鲁木齐830052 江苏省农业科学院经济作物研究所/农业农村部长江中下游棉花和油菜重点实验室江苏南京210014 石河子农业科学研究院新疆石河子832000

为综合评价棉花种质资源的抗旱性,筛选优异抗旱品种(品系),并建立成株期产量抗旱预测模型。对50份棉花种质资源在苗期进行干旱处理,调查其表型性状并测定其生理指标,根据各性状/指标差异的显著性筛选抗旱指标,并计算抗旱系数和抗旱指数... 详细信息

为综合评价棉花种质资源的抗旱性,筛选优异抗旱品种(品系),并建立成株期产量抗旱预测模型。对50份棉花种质资源在苗期进行干旱处理,调查其表型性状并测定其生理指标,根据各性状/指标差异的显著性筛选抗旱指标,并计算抗旱系数和抗旱指数,利用主成分分析法和隶属函数法计算综合抗旱系数、综合抗旱指数、综合抗旱隶属函数值、加权抗旱性系数和抗旱性综合度量值,对棉花抗旱性进行综合评价和分级。进一步将苗期评价分级结果与成株期干旱胁迫下产量和纤维品质性状进行比较,以分析苗期抗旱鉴定模型对成株期预测的精度。苗期生理性状在提高抗旱鉴定模型精度上具有重要作用,基于苗期生理指标建立的抗旱鉴定模型能够很好地预测成株期的抗旱性。

关键词：棉花抗旱性抗旱鉴定抗旱性综合评价抗旱指标相关性分析

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大连地区干旱特征及变化趋势分析

辽宁农业科学 2024年第5期 15-22页

作者：徐建文张黎红侯彦泽李铭王岩大连市气象服务中心辽宁大连116001 大连市防雷减灾中心辽宁大连116001

为探究气候变化背景下大连市干旱特征及变化趋势,基于2007~2023年大连市80个区域自动气象站和1964~2023年6个国家气象站的气象数据,使用相对湿润度指数探讨分析了大连市干旱的时序变化趋势、空间分布规律及概率分布特征。结果表明:(1)... 详细信息

为探究气候变化背景下大连市干旱特征及变化趋势,基于2007~2023年大连市80个区域自动气象站和1964~2023年6个国家气象站的气象数据,使用相对湿润度指数探讨分析了大连市干旱的时序变化趋势、空间分布规律及概率分布特征。结果表明:(1)大连市干旱主要以轻旱为主,发生轻旱的区域主要分布于瓦房店、旅顺和大连市区。相对湿润的区域为东北部地区,相对干旱的区域为西北部地区和旅顺、市区及长海的部分地区。春季以轻旱和中旱为主,瓦房店、旅顺、市区和金普新区的部分地区为中旱,庄河、普兰店和长海大部为轻旱。秋季庄河和普兰店的部分区域为无旱,其他大部分地区以轻旱为主。(2)干旱发生频率较低的区域基本在庄河地区,干旱发生频率较高的地区基本在瓦房店西北部及大连市南部地区的大部分区域。(3)近60年大连市相对湿润度指数呈显著上升趋势,即干旱程度显著减弱。春季、秋季及冬季相对湿润度指数均出现显著上升趋势,干旱显著减弱。(4)近60年大连市的相对湿润度在2002~2003年开始了突变,在2012~2014年发生了突变。(5)近60年大连市无旱年占45%,轻旱年占52%,中旱年占3%,无重旱及特旱年。

关键词：大连地区干旱趋势分析

Polyimide covalent organic frameworks as efficient solid-state Li^(+) electrolytes

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Science China Chemistry 2024年第5期67卷 1647-1652页

作者： xu Liu Shi Wang Siqi Liu Chengfang Liu Xiangchun Li jian Wu Dazhi Li Shihao xu Chongyang Liu wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&TelecommunicationsNanjing 210023China

Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced Li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance LIBs.

关键词： lithium ion batteries(LIBs) covalent organic frameworks(COFs) solid-state ion conductors solid-state electrolytes ion conductivity

Evidence-based practices in sustainable travel behavior intervention: A knowledge graph-based systematic review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 293-311页

作者： jian Li Chenjie xu Key Laboratory of Road and Traffic Engineering of the Ministry of Education College of Transportation EngineeringTongji UniversityShanghai 201804China

Sustainable travel behavior intervention is an essential strategy to promote the development of urban *** interventions offer personalized strategies based on certain scenario and participants to promote its effectiveness over hard travel ***,personalized strategies may also bring about difficulties to identify the actual effect of the ***,based on current practice,to make full use of travel behavior interventions,it is necessary to construct a unified methodological evidencebased framework to assess the reliability and effectiveness of travel behavior intervention *** response to these issues,we applied evidence-based knowledge graph to the field of sustainable travel behavior interventions to help decision supporters design sustainable travel behavior interventions wisely and in turn avoid excessive use of hard travel *** introduced concept of evidence-based practice to conduct a systematic analysis concerning reliability and validity of current full volume empirical studies by dimensions of scenarios,types of interventions and *** addition,we took advantage of high extensivity and integrability of knowledge graph to organize evidence-based related *** of the systematic analysis shows that in terms of reliability of evidence,school intervention is the best scenario,knowledge incentive is the best intervention type and promoting public transit and walking proportion are the best ***,the reliability of interventions in workplace,belonging to reward and threat along with aiming at changing travel patterns generally and lowering travel carbon emission need to be *** the study,various research prospects are raised to promote evidence quality in the field of travel behavior intervention *** a pioneer study,our research contributes to the field of urban transportation in introducing concepts of evidence-based practice and enabling optimization and

关键词： Evidence-based decision-making Evidence assessment Knowledge graph Travel behavior intervention Sustainable travel

The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： jian Bei AN Yong xu Department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let D≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category FD(G).Together with the results of An–Dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups