激光雷达在当阳至远安铁路勘测设计中的应用

激光雷达航空摄影测量技术的迅速发展对空间数据的采集显示出整体发展趋势,并转化为更有效的采集方法。结合激光雷达摄影技术在当阳至远安地形铁路设计勘测实例,解决了航线设计中的技术问题,对GPS数据、点云数据等进行分析,其数据质量满足铁路设计要求。利用激光雷达摄影技术,其地形地貌数据能有效地服务于铁路设计。

Laser performance upgrade for precise ICF experiment in SG-Ⅲ laser facility

The SG-Ⅲlaser facility(SG-Ⅲ)is the largest laser driver for inertial confinement fusion(ICF)researches in China,which has 48 beamlines and can deliver 180 kJ ultraviolet laser energy in 3 ns.In order to meet the requirements of precise physics experiments,some new functionalities need to be added to SG-Ⅲand some intrinsic laser performances need upgrade.So at the end of SG-Ⅲ's engineering construction,the 2-year laser performance upgrade project started.This paper will introduce the newly added functionalities and the latest laser performance of SG-Ⅲ.With these function extensions and performance upgrade,SG-Ⅲis now fully prepared for precise ICF experiments and solidly paves the way towards fusion ignition.

QTL mapping by whole genome re-sequencing and analysis of candidate genes for salt tolerance in linseed(Linum usitatissmum L.)

Soil salinization is detrimental to the growth and development of flax and ultimately leads to a decrease in yield.However,the molecular mechanism of linseed response to salt stress is still unclear.In this study,a salt-tolerant(ST)linseed variety STS and a salt-sensitive(SS)variety DYM were selected as experiment materials.Bulk segregation analysis and whole-genome resequencing technologies were performed to map salt tolerance quantitative trait loci(QTL).A total of 38,625 QTL loci were identified.Fifteen genes(which were not annotated in the reference genome)were identified within a 2.597 Mb region in chromosome 1.Two salt tolerance candidate genes Lus.o.m.scaffold91.141 and Lus.o.m.Scaffold1.14 encoding WD40 and cytochrome P450 were identified by predicting protein functions.Previous studies showed that WD40 and cytochrome P450 could significantly improve plant salt stress tolerance.In this paper,results showed that Lus.o.m.scaffold91.141 and Lus.o.m.Scaffold1.14 might be involved in response to salt stress in lineseed.The fine mapping and functional analysis of these genes provide a molecular breeding basis for the genetic improvement of high salt-tolerant linseed varieties.

深水刚性跨接管设计分析

跨接管广泛应用于较深水及深水海域油气资源的开发项目中,因其结构柔性和安装便捷性,是连接水下结构物的常用选择方案。本文主要依据我国正在开发的南海项目,介绍深水刚性跨接管设计过程中需要重点考虑和关注的技术难点,详细介绍了设计相关参数、壁厚选择、强度计算和疲劳评估等,本文得出的结论可供后续类似工程项目、科研课题等借鉴。

Seed filling dynamic traits of oil flax in response to nitrogen and phosphorus

Crop yield is primarily seed-filling-limited in production system under field conditions.This study was aimed to determine whether seed filling traits of oil flax(Linum usitatissimum L.)could be controlled by phosphorus(P),nitrogen(N),and phosphorus and nitrogen(NP)supply.Effects on seed filling traits were investigated in 2 years including capsule diameter,capsule height,capsule dry matter(DM),seed DM per capsule,pericarp DM per capsule,protein content and oil content.DM translocation from pericarps to seed,translocation efficiency,and contribution of photoassimilates during seed filling period were also detected.In a randomized complete block design,cultivar'Longyaza 1'was grown under P(33 kg P/ha),N(75 kg N/ha),and NP(33 kg P/ha and 75 kg N/ha)along with a zerofertilizer(CK)treatment in 2013 and 2014.Results suggested that DM translocation efficiency and contribution efficiency increased to different extent due to P,N or NP application.At 42 DAA(days after anthesis),seed DM per capsule reached the greatest,while protein content and pericarp DM obtained the least level.However,the highest oil content was detected at 35 DAA.A significant positive linear relationship was observed between seed DM,capsule DM and DM translocation in both years.Protein content showed inconsistent relation with oil content.The results indicated that appropriate N and P management could be an effective approach to increase oil flax production.

Theoretical and Numerical Studies on the Coupling Deformation of Global Lateral Buckling and Walking of Submarine Pipeline

Buckling initiation devices/techniques,including sleepers,distributed buoyancy,snake lay,and residual curvature method(RCM),have recently been widely applied in engineering.These initiated buckles may induce a long pipeline to transform into multiple short pipeline segments,which promote the occurrence of pipeline walking.Thus,a pipeline,which is designed to buckle laterally,may laterally and axially displace over time when subjected to repeated heating and cooling cycles.This study aims to reveal the coupling mechanism of pipeline walking and global lateral buckling.First,an analytic solution is proposed to estimate the walking of pipeline segments between two adjacent buckles.Then,the sensitivity of this method to heating and cooling cycles is analyzed.Results show the applicability of the proposed walking analytical solution of buckling pipelines.Subsequently,an influence analysis of walking on global buckling,including the capacity of buckling initiation,buckling amplitude,buckling mode,and failure assessment of the buckling pipeline,is performed.The results reveal that the effect of walking on the buckling axial force is negligible.However,pipeline walking will aggravate the asymmetry of the pipeline buckling and the failure parameters of the pipeline during the post-buckling.

Secoisolariciresinol diglycoside(SDG)lignan content of oil flax:Genotypic and environmental variations and association with other traits

The secoisolariciresinol diglycoside(SDG)lignan of oil flax(Linum usitatissimum L.)is influenced by genotype,environment and the interaction of genotype×environment.This field study was conducted to investigate the effects of genotype and environment on the SDG lignan content,six genotypes(Longya 8,Zhangya 2,Linxiabai,Shandanbai,Gaolanbai,and DYMS)were sown under eight locations(Hohhot,Datong,Minle,Yili,Shuangta,Jingtai,Guyuan,and Zhangjiakou)in 2014 and 2015 in China.The experimental design was a randomized complete block with three replications.Results showed that Longya 8 had the highest SDG lignan content(7.27mg/g)and Shandanbai had the lowest(4.71 mg/g)across 16 environments.The SDG lignan content ranged from 4.70 mg/g at Datong to 7.74 mg/g at Minle Research Station.In the present study,the results indicated that differences among genotypes in SDG lignan content accounted for 51.38%variation of the total variation and environments accounted for 44.40%variation of the total variation.Moreover,we found that the altitude had a positive effect on SDG lignan content of flaxseed,presumably owing to differences in temperature,humidity,sunshine time,etc.These results indicated that the SDG lignan content was genetically controlled,and was also to be influenced by environmental conditions,especially altitude.

Laser performance of the SG-Ⅲ laser facility

SG-Ⅲ laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%.We review the laser system and introduce the SG-Ⅲ laser performance here.

2016—2022年广州空港口岸疟疾输入性病例的流行病学分析

本文分析了2016—2022年广州空港口岸疟疾输入性病例流行病学特征,探讨防止疟疾输入再传播风险的应对措施。收集了2016—2022年广州白云国际机场入境有症状旅客的卫生检疫样本送样单、疟原虫检测报告,以及智慧卫生检疫系统中的信息资料,采用描述性流行病学方法进行分析。结果发现,2016—2022年广州空港口岸疟疾输入性病例共123例,其中恶性疟109例(88.62%)、间日疟1例(0.81%)、三日疟2例(1.63%)、卵形疟2例(1.63%)、未分型9例(7.32%)。以中国籍海外务工中青年男性为输入病例的主要群体,岁末年初为输入高峰,病例感染来源地以非洲国家或地区为主,共112例(91.06%),感染分型以恶性疟为主,共100例(89.29%)。由此可知,我国疟疾防控的输入性风险仍然存在,国境口岸应持续加强口岸一线的输入性传染病监测,提升实验室检测能力,加强预防性有害生物防治,共同筑牢国境口岸卫生检疫防线。