检索结果-南通市图书馆

Double Andreev reflections at surface states of the topological insulators with hexagonal warping

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2020年第2期15卷 79-86页

作者： Chang-yong Zhu Shi-Han Zheng Hou-jian Duan Ming-Xun deng Rui-Qiang Wang Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China School of Physics and Mechanical and Electrical Engineering Shaoguan UniversityShaoguan 512005China

We study the Andreev reflection(AR)at the interface of the topological insulator with hexagonal warping and superconductor *** to the hexagonal warping effect,the double ARs are found in a certain range of the incident angle,where for one incident electron beam,two beams of holes are reflected ***,both the beams of holes are reflected as retro-AR on the same side of the normal line of the interface but with different reflection angles,different from the previously reported double AR with one retro-AR and one *** double reflections owing to the warping effect show the optics-like property of the Dirac fermion and can stimulate the double reflections of light in anisotropic *** addition,we find that the double ARs are dependent on the hexagonal warping parameter nonmonotonically,and in an intermediate strength the double AR phenomenon is prominent,providing a possibility to explore the warping parameter of topological insulators.

关键词： Andreev reflection topological insulator warping effect

基于Monte Carlo方法的两相流动参数探测不确定性研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

核动力工程 2024年第4期45卷 38-44页

作者：刘丽朱隆祥张卢腾马在勇孙皖潘良明邓坚重庆大学低品位能源利用技术及系统教育部重点实验室重庆400044 重庆大学动力工程及工程热物理博士后科研流动站重庆400044 重庆大学核工程与核技术系重庆400044 中国核动力研究设计院成都610213

气泡速度和气泡数目是计算界面面积浓度等相态特性的关键参数,因此对电导探针测得的气泡速度和数目进行不确定性研究是很有必要的。采用MonteCarlo方法生成大量随机气泡运动样本,得到探针捕获直径1~6mm气泡的统计规律。通过引入相对速... 详细信息

气泡速度和气泡数目是计算界面面积浓度等相态特性的关键参数,因此对电导探针测得的气泡速度和数目进行不确定性研究是很有必要的。采用MonteCarlo方法生成大量随机气泡运动样本,得到探针捕获直径1~6mm气泡的统计规律。通过引入相对速度波动分量H研究了气泡横向速度对有效气泡数目和气泡速度的影响。结果表明,气泡横向速度的存在可缓解由于探针横向间距而无法测量较小气泡的情况;但有效气泡数目随着气泡横向速度的增大显著降低,逃逸气泡数目增加。同时,H=0时,速度误差仅来源于探针横向间距,且速度误差随着气泡直径的增加而减小;H≠0时,对于直径大于3mm的气泡,气泡向左或向右的横向运动反而使得探针从远离中轴线处穿过气泡,导致气泡实际移动距离增大,速度误差也增大。本文研究可为确定及修正界面面积浓度等两相流动参数不确定度提供参考。

关键词： MonteCarlo方法气泡横向速度有效气泡数目撞击角

A method of determining nonlinear large strain consolidation parameters of dredged clays

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2014年第2期7卷 218-226页

作者： Yu-peng CAO Xue-song Wang Long DU jian-wen Ding yong-feng deng Institute of Geotechnical Engineering Southeast University Municipal Facilities Authority Weifang Economic Development Zone

A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. （2010）, a relationship between the void ratio （e） and effective stress （a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient （k） and the ratio （e/eL） of the void ratio to the void ratio at the liquid limit （eL） is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. （1994）. Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g（e） defined by Gibson et al. （1981） and k/（1 ＋e） in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/（1 ＋e） increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.

关键词： initial void ratio permeability large strain consolidation parameter remolded yieldstress dredged clay

HOGG1 polymorphism in atrophic gastritis and gastric cancer after Helicobacter pylori eradication

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2010年第35期16卷 4476-4482页

作者： Lei-Min Sun Yan Shang Ya-Min Zeng Yan-yong deng jian-Feng Cheng Department of Gastroenterology Sir Run Run Shaw Hospital Zhejiang University Hangzhou 310016 Zhejiang Province China the First People’Hospital of Xiaoshan District Hangzhou 311200Zhejiang ProvinceChina Department of Gastroenterology Internal MedicineVirginia Commonwealth UniversityRichmondVA 23298United States

AIM:To investigate the association between Ser326Cys human oxoguanine glycosylase 1(hOGG1) polymorphism and atrophic gastritis and gastric cancer after Helicobacter pylori(***) ***:A total of 488 subjects(73 patients with gastric cancer,160 with atrophic gastritis after *** eradication and 255 controls) were prospectively *** chain reaction-restriction fragment length polymorphism analysis was performed to distinguish hOGG1 Ser326Cys *** analysis was conducted by two-sample t test for continuous variables and χ2 test for categorical *** regression models were used to f ind the risk factors for gastric cancer and atrophic ***:Neither the hOGG1 Ser/Cys nor the Cys/Cys genotype was associated with gastric *** with the Ser/Ser genotype,odds ratio(OR) for Ser/Cys was 0.96,(95% CI:0.51-1.84) and OR for Cys/Cys was 1.1(95% CI:0.48-2.1).No association was detected between hOGG1 polymorphism and Lauren type of gastric cancer(P=0.61) ***,Ser/Cys and Cys/Cys were signif icantly associated with atrophic gastritis with OR:1.76 for Ser/Cys(95% CI:1.03-3.0) and 2.38 for Cys/Cys(95% CI:1.34-4.23).After controlling for age,gender,smoking and alcohol,there were still signif icant associations with OR:2.05 for Ser/Cys(95% CI:1.14-3.68) and 2.76 for Cys/Cys(95% CI:1.47-5.18).CONCLUSION:HOGG1 polymorphisms(Cys/Cys and Ser/Cys) are associated with atrophic *** significant association is detected between hOGG1 polymorphisms(Cys/Cys or Ser/Cys) and gastric cancer.

关键词： Human oxoguanine glycosylase 1 polymorphism Atrophic gastritis Gastric cancer

THREE-DIMENSIONAL FLOW AROUND TWO TANDEM CIRCULAR CYLINDERS WITH VARIOUS SPACING AT Re=220

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2006年第1期18卷 48-54页

作者： deng jian REN An-lu ZOU jian-feng Department of Mechanics Zhejiang University Hangzhou 310027 China

The flow around two tandem circular cylinders was studied by a three-dimensional numerical simulation of the Navier-Stokes equations at Re=220 . The improved virtual boundary method was applied to model the no-slip boundary condition of the cylinders. The results show that as the spac ing ratio L/D≥4 , the three dimensionality occurs in the wake. When L/D≤3.5 the wake keeps a two-dimensional state at the Reynolds number Re=220 . The critical spacing for the appearance of three-dimensional instability obtained is at the range 3.5〈 L/D 〈 4, similar to the critical spacing found in two-dimensional case. Two sources of instability from upstream and downstream cylinder generate a complicat ed vortex structures in the wake, investigated by streamlines topology analysis in the streamwise plane. Many other interesting problems were also addressed in this paper.

关键词： three-dimensional Navier-Stokes equations,virtual boundary method flow around two tandem circular cylinders three-dimensional vortex structure

Absolute density measurement of nitrogen dioxide with cavity-enhanced laser-induced fluorescence

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第10期27卷 260-265页

作者： Zheng-Hai Yang yong-Cheng Yang Lian-Zhong deng jian-Ping Yin State Key Laboratory of Precision Spectroscopy School of Physics and MaterialEast China Normal UniversityShanghai 200062China

The absolute number density of nitrogen dioxide（NO2） seeded in argon is measured with cavity-enhanced laserinduced fluorescence（CELIF） through using a pulsed laser beam for the first time. The cavity ring down（CRD） signal is acquired simultaneously and used for normalizing the LIF signal and determining the relationship between the measured CELIF signal and the NO2 number density. The minimum detectable NO2 density down to（3.6±0.1）10^8 cm^-3 is measured in 60 s of acquisition time by the CELIF method. The minimum absorption coefficient is measured to be（2.0±0.1）10^-9 cm^-1, corresponding to a noise equivalent absorption sensitivity of（2.2±0.1）10^9 cm.^-1Hz^-1/2. The experimental system demonstrated here can be further improved in its sensitivity and used for environmental monitoring of outdoor NO2 pollution.

关键词： cavity-enhanced laser-induced fluorescence (CELIF) cavity ring down (CRD)

大学生网络成瘾与抑郁症状的关系:一个链式中介模型

在线全文

学校读者我要写书评

暂无评论

中国临床心理学杂志 2024年第3期32卷 526-530页

作者：穆克朗王东方欧阳萱邓奇坚中南大学党委组织部长沙410083 中南大学湘雅二医院精神病学科国家精神心理疾病临床医学研究中心国家精神疾病医学中心长沙410011 华南师范大学心理学院华南师范大学心理应用研究中心广州510631

目的:探讨网络受害、网络欺负和精神病样体验在网络成瘾与大学生抑郁症状关系中的链式中介作用。方法:采用修订版中文网络成瘾量表(CIAS-R)、网络欺凌行为量表(CBS)、15条目社区心理评估阳性症状分量表(CAPE-P5)和2条目病人健康问卷(PHQ... 详细信息

目的:探讨网络受害、网络欺负和精神病样体验在网络成瘾与大学生抑郁症状关系中的链式中介作用。方法:采用修订版中文网络成瘾量表(CIAS-R)、网络欺凌行为量表(CBS)、15条目社区心理评估阳性症状分量表(CAPE-P5)和2条目病人健康问卷(PHQ-2)对5824名大学生进行调查。结果:抑郁症状与网络成瘾、网络受害、网络欺负、精神病样体验均呈显著正相关。网络成瘾通过网络受害到抑郁症状、网络成瘾通过网络欺负到抑郁症状、网络成瘾通过精神病样体验到抑郁症状、网络成瘾通过网络受害和精神病样体验到抑郁症状、网络成瘾通过网络欺负和精神病样体验到抑郁症状等五条中介路径均显著。结论:网络受害、网络欺负和精神病样体验在网络成瘾与抑郁症状的关系中起链式中介效应。

关键词：网络成瘾抑郁症状网络受害网络欺负精神病样体验

维普期刊数据库博看期刊

竞赛驱动下的Spark大数据技术与应用课程教学改革探索

在线全文

学校读者我要写书评

暂无评论

教育教学研究前沿

教育教学研究前沿 2024年第4期2卷 33-36页

作者：吴建邓红辉广安职业技术学院四川广安638000

随着大数据技术的快速发展,Spark作为分布式大数据处理框架,已成为企业数据分析和处理的重要工具。竞赛驱动下的Spark大数据技术与应用课程教学改革,旨在通过竞赛项目牵引,促进学生理论学习与实践操作的深度融合,不仅能够激发学生的学... 详细信息

随着大数据技术的快速发展,Spark作为分布式大数据处理框架,已成为企业数据分析和处理的重要工具。竞赛驱动下的Spark大数据技术与应用课程教学改革,旨在通过竞赛项目牵引,促进学生理论学习与实践操作的深度融合,不仅能够激发学生的学习兴趣和积极性,还能促进学生实践能力和创新能力的提升。因而研究竞赛驱动下的Spark大数据技术与应用课程教学改革有重要的意义。对此,课程改革主要围绕教学组织形式、教学方法和评价方式三个方面展开。在教学组织形式上,采用“学生为主体、竞赛为引导”的教学模式,鼓励学生组队参与实际项目;在教学方法上,引入行业企业项目,在实践操作中提升学生的学习效果;在评价方式上,实施竞赛成果为核心的多元化的评价体系,以期提升学生的综合能力和实践能力。

关键词： Spark大数据技术与应用课程改革竞赛驱动

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

一种城轨车辆智能运维全量数据存储优化方案

控制与信息技术 2024年第3期 86-90页

作者：吴亚雄邓健株洲中车时代电气股份有限公司湖南株洲412001

随着城市轨道交通行业的迅猛发展,城轨车辆运营数据量急剧膨胀,传统的全量数据存储方法已难以适应日益增长的数据处理和存储需求。为此,文章提出了一种采用跳变数据技术的数据处理和存储优化方案,其通过相邻时序数据的比对精确识别和存... 详细信息

随着城市轨道交通行业的迅猛发展,城轨车辆运营数据量急剧膨胀,传统的全量数据存储方法已难以适应日益增长的数据处理和存储需求。为此,文章提出了一种采用跳变数据技术的数据处理和存储优化方案,其通过相邻时序数据的比对精确识别和存储数据变化特征,显著降低了城轨车辆运营数据处理的需求,并大幅度减少了存储资源的占用。现场测试表明,本方案在确保数据安全性和稳定性的同时,实现了97.5%的数据处理量减少和97%的存储空间节约,不仅有效缓解了数据传输和存储的压力,而且为城市轨道交通的智能化运维提供了坚实的数据支持。

关键词：城轨车辆运营数据数据存储智能运维