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螺纹桩中性点位置及轴力计算方法研究

铁道科学与工程学报 2022年第7期19卷 1908-1917页

作者：周芝林珠海香海大桥有限公司广东珠海519000

挤密螺纹桩(以下简称螺纹桩)桩身螺纹结构的存在,改变了桩身与桩周土的力学作用方式,能有效增强螺纹桩复合地基承载能力及控制沉降的能力。掌握地面堆载引起的螺纹桩与桩周土的差异沉降和中性点位置可为其分析、设计及状态评估提供参考... 详细信息

挤密螺纹桩(以下简称螺纹桩)桩身螺纹结构的存在,改变了桩身与桩周土的力学作用方式,能有效增强螺纹桩复合地基承载能力及控制沉降的能力。掌握地面堆载引起的螺纹桩与桩周土的差异沉降和中性点位置可为其分析、设计及状态评估提供参考和依据。基于荷载传递法,建立螺纹桩复合地基单桩力学模型。依据桩侧土与螺纹下地基土处于3种不同的弹塑性变形阶段,分别推导轴力解析表达式并确定了中性点位置。通过三维有限元分析验证理论计算结果,研究结果表明:二者轴力沿桩身分布曲线吻合较好,螺纹桩中性点深度比处于0.40~0.50之间,中性点位置误差低于12%。随着荷载的增加,误差逐渐减小,说明提出的轴力计算方法能较好应用于螺纹桩。桩长由4 m增加到8 m时,中性点深度比增加了20.54%。螺纹桩螺纹宽度在0.05~0.2 m,螺纹间距在0.15~0.6 m范围变化时,中性点位置变化幅度均不超过3.1%,表明螺纹宽度与螺纹间距对中性点位置影响较小。考虑复合地基中螺纹桩受桩侧负摩阻力影响的特点,分析模型满足了螺纹桩的受力特点,且计算过程简便。研究成果可为螺纹桩的设计计算与工程应用提供理论支持。

关键词：螺纹桩荷载传递法负摩阻力中性点位置三维有限元分析

Resequencing of sweetpotato germplasm resources reveals key loci associated with multiple agronomic traits

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Horticulture Research 2023年第1期10卷 128-139页

作者： Shizhuo Xiao Xibin Dai Lingxiao Zhao zhilin zhou Lukuan Zhao Pan Xu Bingqian Gao An Zhang Donglan Zhao Rui Yuan Yao Wang Jie Wang Qinglian Li Qinghe Cao Jiangsu Xuzhou Sweetpotato Research Center/Sweetpotato Research Institute Chinese Agricultural Academy of SciencesXuzhou 221131China College of Pastoral Agriculture Science and Technology Lanzhou UniversityLanzhou 730020China

Sweetpotato is an important crop that exhibits hexaploidy and high heterozygosity,which limits gene mining for important agronomic ***,314 sweetpotato germplasm resources were deeply resequenced,and 4599509 SNPs and 846654 InDels were generated,among which 196124 SNPs were nonsynonymous and 9690 InDels were *** on the Indels,genome-wide marker primers were designed,and 3219 of 40366 primer pairs were selected to construct the core InDel marker *** molecular ID of 104 sweetpotato samples verified the availability of these *** sweetpotato population structures were then assessed through multiple approaches using SNPs,and diverse approaches demonstrated that population stratification was not obvious for most Chinese germplasm *** many as 20 important agronomic traits were evaluated,and a genome-wide association study was conducted on these traits.A total of 19 high-confidence loci were detected in both *** loci included several candidate genes,such as IbMYB1,IbZEP1,and IbYABBY1,which might be involved in anthocyanin metabolism,carotenoid metabolism,and leaf morphogenesis,*** them,IbZEP1 and IbYABBY1 were first reported in *** variants in the promoter and the expression levels of IbZEP1 were significantly correlated with f lesh color(orange or not orange)in *** expression levels of IbYABBY1 were also correlated with leaf *** results will assist in genetic and breeding studies in sweetpotato.

关键词： germplasm breeding traits

Survey sequencing and flow cytometry reveal the genomic backgrounds of seven wild species of sweetpotato

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Survey sequencing and flow cytometry reveal the genomic back...

Study of a model for correcting the effects of horizontal advection on surface fluxes measurement based on remote sensing

第二十届中国作物学会学术年会

作者：王珧 Deng Yitong Zhao Lukuan zhou zhilin 曹清河 Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District (XIAS)

【Backgrounds】Ipomoea is the biggest genera in the family Convolvulaceae, owning 800-900 species. There are diploid, tetraploid, and hexaploid species in Ipomoea, while many wild species have excellent resistance genes. Sweetpotato(Ipomoea batatas(L.) Lam.) is the seventh largest food crop in the world and is widely planted in tropical and subtropical areas due to its wide adaptability. Wild sweetpotatoes are an important source of excellent genetic and genetic diversity of sweetpotatoes. However, genomic and genetic research on sweetpotato is limited, and the origin of the species remains inconclusive. Only a few sweetpotato genera have genome sketches, making it difficult to breed new varieties using wild species of sweetpotato. About 13 wild species of this genus belong to the Ipomoea section Batatas. The genomic information of the Ipomoea section Batatas can be used to study the sweetpotato genome and the evolutionary patterns, as well as to reveal the relationship between the genes of different species, thereby elucidating the origin and evolution of this species. 【Material and Methods】To facilitate the development of sweetpotato varieties using genomic and genetic approaches, we assessed the genome size and ploidy level of seven closely related wild species(I. lacunosa, I. tilliacea, I. tenussima, I. leucantha, I. purpurea, I. tabascana, and I. trifida(6x)) of sweet potato by flow cytometry and chromosome counting, and acquired their genomic backgrounds using high-throughput sequencing. 【Results and Analysis】 Based on the 17-mer frequency distribution, the genome size of these species ranged from 477.27 Mbp to 1,505.04 Mbp. Most of the diploid species had a genome size of about 500 Mb, and the two diploid wild species I. leucantha and I. purpurea had much greater genome sizes than the remaining diploid species, showing highly significant differences in genome size. A large proportion of repeats(55.22%–81.07%) in the genomes of the seven species, I. trifida(6x)(

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Science China Earth Sciences 2006年第S2期49卷 273-280页

作者： TIAN Jing, ZHANG Renhua, SUN Xiaomin, ZHU zhilin & zhou Yanlian Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate University of the Chinese Academy of Sciences, Beijing 100049, China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate University of the Chinese Academy of Sciences Beijing China

As well known, the methods of remote sensing and Bowen Ratio for retrieving surface flux are based on energy balance closure; however, in most cases, surface energy observed in experiment is lack of closure. There are two main causes for this: one is from the errors of the observation devices and the differences of their observational scale; the other lies in the effect of horizontal advection on the surface flux measurement. Therefore, it is very important to estimate the effects of horizontal advection quantitatively. Based on the local advection theory and the surface experiment, a model has been proposed for correcting the effect of horizontal advection on surface flux measurement, in which the relationship between the fetch of the measurement and pixel size for remote sensed data was considered. By means of numerical simulations, the sensitivities of the main parameters in the model and the scaling problems of horizontal advection were analyzed. At last, by using the observational data acquired in agricultural field with relatively homogeneous surface, the model was validated.

关键词： fetch horizontal advection energy balance pixel size ChinaFLUX.

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佛开高速公路北江大桥改造前后力学性能分析

广东公路交通 2014年第4期40卷 29-33页

作者：周芝林广东省高速公路有限公司广州510623

佛开高速公路北江大桥采用主桥拆除重建、引桥顶升加固的改造方案。由于引桥连续工字梁存在结构性病害,顶升对梁体的影响需进行评估。同时,顶升误差将导致梁体产生次应力,可能导致梁体出现新的损伤,此外,顶升过程中连续工字梁的结构体... 详细信息

佛开高速公路北江大桥采用主桥拆除重建、引桥顶升加固的改造方案。由于引桥连续工字梁存在结构性病害,顶升对梁体的影响需进行评估。同时,顶升误差将导致梁体产生次应力,可能导致梁体出现新的损伤,此外,顶升过程中连续工字梁的结构体系多次发生转换,多次体系转换后梁体的受力性能是否满足要求需进行分析。对北江大桥引桥连续工字梁的典型联跨改造前后的受力性能进行分析,得到其受力性能的变化规律,为桥梁改造施工提供理论依据。

关键词：桥梁旧桥改造力学性能测试分析

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新形势下严肃党内政治生活的思考

武警工程大学学报 2017年第3期33卷 12-16页

作者：周治林武警工程大学军事基础教育学院西安710086

党的十八届六中全会聚焦全面从严治党的主题，认为“党要管党，首先要从党内政治生活管起；从严治党，首先要从党内政治生活严起。”并审议通过了《关于新形势下党内政治生活的若干准则》这一党内法规。贯彻落实党的十八届六中全会精神... 详细信息

党的十八届六中全会聚焦全面从严治党的主题，认为“党要管党，首先要从党内政治生活管起；从严治党，首先要从党内政治生活严起。”并审议通过了《关于新形势下党内政治生活的若干准则》这一党内法规。贯彻落实党的十八届六中全会精神，就要深刻认识严肃党内政治生活的重大意义，准确把握当前党内政治生活存在的主要问题，切实找准新形势下解决问题的思路对策，进一步净化政治生态，打牢全面从严治党的基础，提高全面从严治党的实效。

关键词：十八届六中全会党内政治生活落实对策

Deep sequencing and de nove assembly of the diploid Ipomoea trifida(H.B.K.)*** and SSR markers development

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Deep sequencing and de nove assembly of the diploid Ipomoea ...

Study On The Endophytic Fungi Associated With Illicium verum

遗传学与表观遗传学前沿暨第三届中国青年遗传学家论坛

作者： Qinghe Cao Shan Gao Zhiming Wu Ang Li An Zhang Jun Tang zhilin zhou Donglan Zhao Daifu Ma Key Laboratory of Biology and Genetic Improvement of Sweet Potato Ministry of AgricultureP.R.China/Jiangsu Xuzhou Sweetpotato Reasearch Centre College of Life Sciences Nankai University Institute of Commercial Crops Research Hebei Academy of Agricultural Sciences

Backgrounddpomoea triflda(H.B.K.)*** one closest wild relative of cultivated *** owns abiotic and biotic stress resistance and can be used to improve the ***,the diploid *** is a good reference module plant of the genome sequencing,transcriptome and Self-incompatibility for complicated highly heterozygous hexaploid ***,high throughput transcriptoms sequencing is needed to generate enormous transcript sequences from wild elite genes discovery and molecular marker ***:Using high-throughput illumina RNA-seq,the transcriptome of dipolid *** was analyzed at an unprecedented depth(6.69 gigabase pairs).Approximate 47.4 million reads were obtained,trimmed,and assembled into 65,731 unigenes,with an average length of 959.1bp and N50 1198 *** number of unigenes of was about 47 times higher than existing *** EST sequences deposited in Genbank(as of October 2013).Based on sequence similarity search with known protein database and following annotation,52,783 unigenes(80.3%)were annotated by the NR databases,39,803 unigenes were annotated by GO terms,and 15,937 unigenes were assigned to 290 KEGG *** with transcriptome data from our hexaploid cultivar Xushu 18by Blast,54,510(83%)out of the 65,731 unigenesin theI,triflda transcriptome were mapped to48,571(88%)out of the 55,181unigenesin theI,batatas transcriptome with the e-value 1.0 ***,microsatellites(single sequence repeats)were detected as potential molecular markers in ***.100 hundred primer pairs for SSRs were designed for validation of the amplification and *** result showed that 93 of 100 primer pairs were successfully amplified and 68 of them exhibited polymorphismsbetween diploid and ***/Significance:This is the first report of a transcriptome database for diploid Ipomoea triflda,which enriches the genomic resources of sweetpotato wild ***,some novel special unigenes co

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Study On The Endophytic Fungi Associated With Illicium verum

灌浆套筒连接的节段预制桥墩抗推滞回性能参数分析

2008年中国微生物学会学术年会

作者： CHEN Youwei~*,WU Shaohua,JI zhilin,Miao cuibing and zhou Bihua (Yunnan Institute of Microbiology,Yunnan University,Kunming 650091,China)

In this paper we selected different Illicium verum as material to separate and identify its endophytic *** also did the bioactive screening and selected the endophytic fungi that had strong and stable inhibiting activities as the original strains,and their active compounds were *** achievements were briefly summarized as follows:

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铁道建筑 2023年第11期63卷 87-91页

作者：周芝林张乐张勇胡俊珠海香海大桥有限公司广东珠海519000 重庆交通大学土木工程学院重庆400074 中国铁道科学研究院集团有限公司铁道建筑研究所北京100081

为研究灌浆套筒连接对节段预制桥墩抗推滞回性能的影响,在灌浆套筒连接的预拼桥墩标准组模型基础上,选取连接钢筋直径、节段划分数量、灌浆套筒长度、配筋率作为参数,利用ABAQUS有限元软件建立预制桥墩精细化模型进行低周反复荷载作用... 详细信息

为研究灌浆套筒连接对节段预制桥墩抗推滞回性能的影响,在灌浆套筒连接的预拼桥墩标准组模型基础上,选取连接钢筋直径、节段划分数量、灌浆套筒长度、配筋率作为参数,利用ABAQUS有限元软件建立预制桥墩精细化模型进行低周反复荷载作用下全过程的非线性有限元分析。采用钢筋等效模拟套筒连接,利用钢筋应力-应变关系滞回模型模拟钢筋在荷载作用下产生的滑移,得到墩顶位移与荷载数据,从而进行参数化分析。结果表明:套筒内连接钢筋直径过小容易造成抗推性能降低,在满足钢筋最大配筋率要求的前提下,应尽量增大纵筋直径;节段数量对桥墩的抗推能力影响较小;套筒长度对桥墩的抗推性能没有明显影响,实际工程中满足最小长度要求即可;桥墩的抗推承载力随配筋率的提高而增大;桥墩的残余位移几乎不受各参数的影响。

关键词：节段预制桥墩灌浆套筒有限元分析抗推性能参数分析