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Organic Chemistry Frontiers 2022年第5期9卷 1410-1416页

作者： mengyang shen Yuanshuang Xu Xinying Zhang Xuesen Fan NMPA Key Laboratory for Research and Evaluation of Innovative Drug Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan 453007China

A novel synthesis of spirocyclopropylpyrazole derivatives tethered with a trifluoromethyl unit through an unprecedented cascade reaction of alkylidenecyclopropanes with pyrazolidinones and trifluoroethanol(TFE)has bee... 详细信息

关键词： alkyl ethanol spiro

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郑州市女大学生网购服装消费行为分析

山东纺织经济 2022年第6期39卷 36-39,43页

作者：沈梦阳李月武汉纺织大学服装学院湖北武汉430073

大学生是整个社会中最具有活力的消费者群体,而女大学生的消费能力更加突出。文章以郑州市女大学生这一消费群体为研究对象,对其网购服装的消费行为进行研究。运用SPSS软件进行描述性、聚类分析,对郑州市女大学生网购服装的购买能力、... 详细信息

大学生是整个社会中最具有活力的消费者群体,而女大学生的消费能力更加突出。文章以郑州市女大学生这一消费群体为研究对象,对其网购服装的消费行为进行研究。运用SPSS软件进行描述性、聚类分析,对郑州市女大学生网购服装的购买能力、购买动机、购买满意度等进行分析,为服装企业在电商市场的发展和进步提出具有针对性的建议。

关键词：郑州女大学生服装消费行为

基于CLO3D虚拟技术下莫高窟61窟回鹘夫人服饰结构分析

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服饰导刊 2023年第1期12卷 6-14页

作者：沈梦阳李月王小刚武汉纺织大学服装学院武汉430073 武汉纺织大学计算机与人工智能学院武汉430073

莫高窟壁画中回鹘夫人服饰图案为多元文化交融下的产物,对其服装结构的分析有助于当下对历史服装的创新设计和应用。文章采用比例法、文献查阅法、CLO3D虚拟试衣软件对历史壁画进行深入研究,建立三维人体模型和服装板型。从款式、色彩... 详细信息

莫高窟壁画中回鹘夫人服饰图案为多元文化交融下的产物,对其服装结构的分析有助于当下对历史服装的创新设计和应用。文章采用比例法、文献查阅法、CLO3D虚拟试衣软件对历史壁画进行深入研究,建立三维人体模型和服装板型。从款式、色彩、面料、服装结构、人体数据及最终着装效果进行仿真复刻,并对复刻效果与史实对比分析并检验,最终采用真实面料进行实物制作。研究表明:回鹘夫人所穿交领长袍是通过胸部飘带固定胸前领子结构造型,腰部飘带固定衣身结构造型;通过比例法准确计算出回鹘夫人人体以及服装各部位数据,绘制出的交领长袍结构图呈现出十字型结构,将服装进行虚拟试衣模拟,对服装面料、色彩、纹样进行仿真,最终效果与壁画效果契合,为古代少数民族服装复刻以及历史服装数字化仿真数据库的研究做基础。

关键词： CLO3D虚拟技术莫高窟回鹘夫人服饰结构比例法人体数据

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橡胶集料高强混凝土高温前后性能研究

工业建筑 2017年第1期47卷 113-117页

作者：周梅沈梦阳张倩辽宁工程技术大学建筑工程学院辽宁阜新123000

以橡胶颗粒部分取代细集料砂子配制高强混凝土,研究橡胶颗粒不同取代率(体积分数)对高强混凝土工作性、高温后质量和强度的损失,并用电镜表征高温前后硬化水泥基体的微观结构。研究结果表明:常温下橡胶集料高强混凝土的表观密度随着橡... 详细信息

以橡胶颗粒部分取代细集料砂子配制高强混凝土,研究橡胶颗粒不同取代率(体积分数)对高强混凝土工作性、高温后质量和强度的损失,并用电镜表征高温前后硬化水泥基体的微观结构。研究结果表明:常温下橡胶集料高强混凝土的表观密度随着橡胶颗粒掺量的递增而下降。抗压强度随橡胶颗粒掺量的递增表现为先减后增,当掺量为6%时强度最低。硬化水泥基体微观结构致密,水泥水化产物结晶发达,600℃高温作用后,混凝土表观密度、抗压和劈拉强度明显下降,但适当掺入橡胶颗粒可以明显提高混凝土强度剩余百分率。高温后硬化水泥基体微观结构疏松、孔隙增大,粗集料以及水泥基体均产生裂纹,水泥水化产物结晶消失。

关键词：橡胶颗粒掺量高强混凝土高温抗压强度微观结构

Velocity structure and radial anisotropy beneath the northeastern Tibetan Plateau revealed by eikonal equation-based teleseismic P-wave traveltime tomography

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Science China Earth Sciences 2022年第5期65卷 824-844页

作者： mengyang LI Shaolin LIU Dinghui YANG Xiwei XU Wenhao shen Chaodi XIE Wenshuai WANG Shuxin YANG National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China School of Earth Sciences Yunnan UniversityKunming 650091China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The northeastern Tibetan Plateau serves as the frontier for the northeastward expansion of the plateau.In this area,the Tibetan Plateau interacts with the surrounding blocks,such as the Alxa Block,the Ordos Block,the Kunlun-West Qinling belt and the Sichuan Basin.Because of this expansion and interaction,this area suffers from intense deformation.At present,the evolution and deformation mechanisms of the northeastern Tibetan Plateau remain controversial.To provide new insights into these mechanisms,in this study,we conduct tomography of the P-wave velocity and radial anisotropy structures beneath the northeastern Tibetan Plateau.We choose a total of 667 teleseismic earthquakes from August 2006 to October 2020.Waveforms of these earthquakes were recorded by 921 broadband seismic stations in the northeastern Tibetan Plateau and surrounding areas.We first perform cross-correlation on waveforms of each station pair and obtain 770,749 P-wave traveltime differences.Then,we invert the differential traveltime data by applying eikonal equation-based teleseismic tomography.Finally,the P-wave velocity and radial anisotropy structures at depths from 30 to 800 km below the northeastern Tibetan Plateau are obtained.Our tomographic model shows clear low-velocity anomalies and positive radial anisotropy in the lower crust under the northeastern Qilian orogen,the northeastern Songpan-Ganzi belt and the western Qinling fold zone.These features are integrated to demonstrate the existence of lower crustal flow in the study area.Prominent low-velocity anomalies and positive radial anisotropy are found in the uppermost mantle beneath the Qilian orogen,the northeastern Songpan-Ganzi belt and western Qinling fold zone.These characteristics are combined to infer a weak lithosphere and horizontal asthenospheric flow under these tectonic units.Both the Ordos Block and the Sichuan Basin exhibit clear high-velocity anomalies and negative radial anisotropy in the uppermost mantle,thereby reflecting the high mechanical strength of the lithosph

关键词： Northeastern Tibetan Plateau Tomography P-wave velocity Radial anisotropy structure Indian plate

SBAS-InSAR技术在河北三河市地面沉降演化特征及成因分析中的应用

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中国地质灾害与防治学报 2024年第3期35卷 97-107页

作者：高启凤张磊赵萌阳李峰李海君谌华李小华周萌华北地质勘查局综合普查大队河北燕郊065201 防灾科技学院生态环境学院河北燕郊065201 防灾科技学院应急管理学院河北燕郊065201

2003—2016年,三河市地面沉降速率逐步加大,其中燕郊地区地面沉降最严重,已和北京通州沉降区连成一片,2016年之后三河市地面沉降灾害的发展变化趋势尚不明确。随着京津冀一体化发展、北京城市副中心建设等国家政策的出台,查明三河市地... 详细信息

2003—2016年,三河市地面沉降速率逐步加大,其中燕郊地区地面沉降最严重,已和北京通州沉降区连成一片,2016年之后三河市地面沉降灾害的发展变化趋势尚不明确。随着京津冀一体化发展、北京城市副中心建设等国家政策的出台,查明三河市地面沉降灾害的发展演化特征并分析成因对保障三河市的城市安全和可持续发展至关重要。文章采用SBAS-InSAR技术解译三河市2018—2020年地面沉降发展演化特征,同时分析了导致三河市地面沉降的几个诱发因素,总结沉降原因。通过本次研究,掌握了三河市地面沉降灾害的空间分布及演化特征:三河市地面沉降在空间上呈现西部严重,东部较缓,发育重点沉降区的总体特征;主要发育有2个重点沉降区,分别为含3个沉降漏斗的燕郊镇沉降区和含1个沉降漏斗的段甲岭镇沉降区,其中燕郊镇沉降区为三河市地面沉降最为严重的区域;2018—2020年,三河市地面沉降灾害总体呈现减缓趋势。同时通过对比分析,三河市地下水的严重超采、土层性质、城镇化发展及人口激增是三河市地面沉降灾害发生及发展的主要因素。研究成果将为该区域地面沉降灾害的防治提供参考。

关键词：三河市 SBAS-InSAR 地面沉降地下水超采城镇化发展成因分析

A review of the influencing factors on teleseismic traveltime tomography

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Earthquake Science 2023年第3期36卷 228-253页

作者： Yang Pan Shaolin Liu Dinghui Yang Wenshuai Wang Xiwei Xu Wenhao shen mengyang Li National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China School of Mathematics and Statistics Ningxia UniversityYinchuan 750021China School of Earth Sciences Yunnan UniversityKunming 650091China

Teleseismic traveltime tomography is an important tool for investigating the crust and mantle structure of the Earth.The imaging quality of teleseismic traveltime tomography is affected by many factors,such as mantle heterogeneities,source uncertainties and random noise.Many previous studies have investigated these factors separately.An integral study of these factors is absent.To provide some guidelines for teleseismic traveltime tomography,we discussed four main influencing factors:the method for measuring relative traveltime differences,the presence of mantle heterogeneities outside the imaging domain,station spacing and uncertainties in teleseismic event hypocenters.Four conclusions can be drawn based on our analysis.(1)Comparing two methods,i.e.,measuring the traveltime difference between two adjacent stations(M1)and subtracting the average traveltime of all stations from the traveltime of one station(M2),reveals that both M1 and M2 can well image the main structures;while M1 is able to achieve a slightly higher resolution than M2;M2 has the advantage of imaging long wavelength structures.In practical teleseismic traveltime tomography,better tomography results can be achieved by a two-step inversion method.(2)Global mantle heterogeneities can cause large traveltime residuals(up to about 0.55 s),which leads to evident imaging artifacts.(3)The tomographic accuracy and resolution of M1 decrease with increasing station spacing when measuring the relative traveltime difference between two adjacent stations.(4)The traveltime anomalies caused by the source uncertainties are generally less than 0.2 s,and the impact of source uncertainties is negligible.

关键词： teleseismic tomography influencing factors relative traveltime differences mantle heterogeneities station spacing

Construction of a high-density mutant population of Chinese cabbage facilitates the genetic dissection of agronomic traits

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Molecular Plant 2022年第5期15卷 913-924页

作者： Xiaoxue Sun Xing Li Yin Lu Shan Wang Xiaomeng Zhang Kang Zhang Xiangjie Su mengyang Liu Daling Feng Shuangxia Luo Aixia Gu Yu Fu Xueping Chen Shuxin Xuan Yanhua Wang Donghui Xu Shumin Chen Wei Ma Shuxing shen Feng Cheng Jianjun Zhao State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaoding 071000China Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture and Rural AffairsSino-Dutch Joint Laboratory of Horticultural GenomicsBeijing 271000China

Chinese cabbage(Brassica rapa ssp.pekinensis)is an economically important vegetable crop throughout the world,especially in Asia.High-quality genome sequences are available for Chinese cabbage,but gene functional studies remain challenging.To promote functional genomic studies of Chinese cabbage,we generated an ethyl methane sulfonate(EMS)mutant population of~8000 M_(2) plants using the double haploid inbred line A03 as the parent.The genome of A03 was sequenced and used as a reference for high-throughput functional characterization of gene mutations at the whole-genome level.A total of 300 M_(2) to M_(5) EMS mutants were phenotypically screened and then sequenced,revealing 750629 SNPs and 46272 InDel mutations that cover 98.27%of all predicted genes in the A03 genome.A forward-genetics approach was successfully used to identify two genes with chloroplast-related functions that are responsible for the yellow leaf mutant trait.A reverse-genetics approach was also used to identify associations between mutations in five genes of the glucosinolate biosynthetic pathway and variations in glucosinolate content of the mutant plants.In addition,we built the Chinese cabbage EMS mutation database(CCEMD,***/EMSmutation/home)to increase the usability of this mutant population resource.In summary,we performed large-scale screening of a heading Chinese cabbage EMS mutant collection at the phenotypic and genotypic levels,which will facilitate gene mining of Chinese cabbage and might also be useful for the study of other Brassica crops.

关键词： Chinese cabbage EMS morphological variations whole-genome sequencing functional genomics

基于程函方程的初至P和sPg波走时联合地震定位方法

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地球物理学报 2023年第12期66卷 4944-4957页

作者：李孟洋刘少林潘阳杨顶辉申文豪徐锡伟中国科学院大学地球与行星科学学院北京100049 应急管理部国家自然灾害防治研究院北京100085 上海佘山地球物理国家野外科学观测研究站上海201602 清华大学数学科学系北京100084 中国地质大学(北京)地球科学与资源学院北京100083

由于初至波到时对震源深度敏感程度低,导致初至波到时定位难以获得可靠的震源深度信息.为了提升震源深度的定位精度,前人提出深度震相走时约束.深度震相定位方法利用深度震相对震源深度敏感的性质测定震源深度,极大的提高了震源深度的... 详细信息

由于初至波到时对震源深度敏感程度低,导致初至波到时定位难以获得可靠的震源深度信息.为了提升震源深度的定位精度,前人提出深度震相走时约束.深度震相定位方法利用深度震相对震源深度敏感的性质测定震源深度,极大的提高了震源深度的精确度.深度震相定位方法中,理论走时常在层状模型中计算获得,当实际地下结构与层状模型之间存在较大差异时,由深度震相方法测定的震源深度将会偏离真实深度.为了提高震源深度的测定精度以及减小速度模型误差对地震定位的影响,本文使用快速行进法求解程函方程获得非均匀模型中的初至P和sPg震相走时,并联合这两种走时开展重定位研究.以2022年四川泸定MS6.8地震为例的合成数据测试和实际定位结果显示,本文基于程函方程的初至P和sPg波走时联合地震定位方法能显著提高地震定位的精度.

关键词：地震定位深度震相程函方程区域非均匀模型

农业产业组织能否影响农户安全生产行为——来自陕西省眉县500户猕猴桃种植户的证据

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农业技术经济 2022年第1期 114-128页

作者：牛文浩申淑虹蔡孟洋张蚌蚌西北农林科技大学经济管理学院杨凌712100

本文基于陕西省眉县500户农户的入户调研数据,运用Logit模型分析影响农户加入农业产业组织的诱因,采用倾向得分匹配(PSM)法测算农业产业组织对农户安全生产行为的影响效应,并比较影响效应在不同年龄、受教育程度、种植规模下的组群差异... 详细信息

本文基于陕西省眉县500户农户的入户调研数据,运用Logit模型分析影响农户加入农业产业组织的诱因,采用倾向得分匹配(PSM)法测算农业产业组织对农户安全生产行为的影响效应,并比较影响效应在不同年龄、受教育程度、种植规模下的组群差异。研究发现,户主的年龄、农户参加安全质量培训次数、猕猴桃种植规模、对《农产品质量安全法》的了解程度和政府检测猕猴桃农药残留次数是影响农户加入农业产业组织主要诱因;农户加入农业产业组织能够显著带动其采取安全生产行为;农业产业组织对农户安全生产行为的影响存在明显的组群差异,户主年龄为55岁及以下、户主受教育程度为初中及以上、猕猴桃种植规模为10亩以下的农户加入农业产业组织后,其安全生产行为的改善程度明显高于其他类型农户。因此,本文提出要引导农户加入农业产业组织,通过各种补贴政策支持各类农业产业组织发展,更好地发挥农业产业组织对农户尤其是特定农户群体安全生产行为的带动作用。

关键词：猕猴桃种植户农业产业组织安全生产行为倾向得分匹配法