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Numerical Study of Flow Features Around Submerged Circular and Square Piles at Flat and Scoured Beds Using OpenFOAM

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Journal of Ocean University of China 2024年第4期23卷 897-914页

作者： WANG Chaolin WU Guoxiang WANG Dianhe DU Shengtao ZHANG Zhiyong jin heng ZHU David Z. LIANG Bingchen Donghai Academy School of Civil&Environmental Engineering and Geography ScienceNingbo UniversityNingbo 315211China Key Laboratory of Estuary and Coast of Zhejiang Province and Zhejiang Institute of Hydraulics and EstuaryHangzhou 310020China Shandong Provincial Key Laboratory of Ocean Engineering and College of EngineeringOcean University of ChinaQingdao 266100China Shandong Water Conservancy Vocational College Rizhao 276826China School of Mechanical and Energy Engineering Ningbotech UniversityNingbo 315211China

Elucidating the flow features around piles in local scouring processes is crucial for studies of local scouring mechanisms and scour depth *** study details the flow turbulence characteristics of two submerged piles that are determined by solving the Navier-Stokes equations with the improved delayed detached eddy simulation *** model is verified by comparing experimental and numerical results for hydrodynamic parameters with the literature for both square-crossing piles(SCPs)and circular-crossing piles(CCPs).Original topographies of flat and scoured beds(i.e.,the initial and equilibrium scouring stages)are based on experimental results obtained by the authors in the present *** and CCP flow features in the scouring process are *** results indicate that during the scouring process,the time-averaged drag coefficient and root mean square(rms)of the lift coefficient increase linearly in the CCP test,while the rms of the lift coefficient in the SCP test decreases ***,the minimum pressure coefficient is always located in the upstream corners in the SCP case but moves from 72.5°to 79.5°when the scour hole is completely developed in the CCP *** flow behind the pile,which is generated by separated boundary layers above the top face of the pile,can reach the sand bed and turn the separated shear layers into patches of small vortices in the near-wake ***,the high shear stress zones are mainly at the scour edges under scoured-bed conditions.

关键词： flat bed scoured bed local scour OpenFOAM bed shear stress

龙岩市永定区城乡供水一体化项目管线布置及施工质量控制

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山西水利科技 2024年第2期 36-38,44页

作者：江亨锦龙岩市永定区水利水电工程质量技术站福建龙岩364100

多年来,我国多个省市陆续加大投入,开展了城乡供水一体化工作的探索,各地区呈现出不同的模式与做法。如何更好地推进城乡供水一体化建设,做好农村供水,成为需要行业共同思考的话题。通过龙岩市永定区城乡供水一体化项目寨下片区工程实例... 详细信息

多年来,我国多个省市陆续加大投入,开展了城乡供水一体化工作的探索,各地区呈现出不同的模式与做法。如何更好地推进城乡供水一体化建设,做好农村供水,成为需要行业共同思考的话题。通过龙岩市永定区城乡供水一体化项目寨下片区工程实例,论述了管线布置、沟槽开挖、管道铺设、管道回填、压水试验施工技术,供类似工程参考。

关键词：城乡供水一体化供水工程质量控制

休耕对抚仙湖周边农田土壤剖面和浅层地下水中氮累积的影响

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环境科学 2024年第6期45卷 3225-3233页

作者：叶远行陈安强李林闵金恒王炽闫辉张丹云南农业大学资源与环境学院昆明650201 云南省农业科学院农业环境资源研究所昆明650201

减少外源氮投入能有效降低农田土壤氮累积和地下水氮污染,休耕是减少外源氮投入的重要措施之一.为探讨农田休耕对土壤剖面和浅层地下水中氮累积的影响,以抚仙湖周边农田土壤剖面和浅层地下水为研究对象,分析了休耕前(2017年12月)和休耕... 详细信息

减少外源氮投入能有效降低农田土壤氮累积和地下水氮污染,休耕是减少外源氮投入的重要措施之一.为探讨农田休耕对土壤剖面和浅层地下水中氮累积的影响,以抚仙湖周边农田土壤剖面和浅层地下水为研究对象,分析了休耕前(2017年12月)和休耕后(2020年8月和2021年4月)农田0~100 cm土壤剖面氮累积和浅层地下水中氮浓度的变化及其两者的关系.结果表明:休耕显著降低了土壤剖面氮含量和储量,休耕后0~30、30~60和60~100 cm土壤剖面TN、ON、DTN、NO_(3)^(-)-N和NH_(4)^(+)-N含量分别降低18.4%~36.5%、16.1%~26.8%、54.0%~130.2%、59.5%~90.8%和60.1%~110.6%.休耕前0~100 cm土壤TN、ON、DTN、NO_(3)^(-)-N和NH_(4)^(+)-N储量分别为(17.20±0.97)t·hm^(-2)、(15.50±1.23)t·hm^(-2)、(0.68±0.06)t·hm^(-2)、(266.8±31.17)kg·hm^(-2)和(18.7±3.04)kg·hm^(-2),休耕后各形态氮储量分别下降了25.5%、23.3%、44.7%、80.1%和59.9%.休耕也改变了浅层地下水中氮浓度和形态构成,休耕后地下水中TN、ON、NO_(3)^(-)-N和NH_(4)^(+)-N浓度分别下降了88.4%、82.7%、92.1%、65.8%,ON/TN和NH_(4)^(+)-N/TN从休耕前的26%和6%升高至休耕后的39%和17%,而NO_(3)^(-)-N/TN从休耕前的61%降至休耕后的41%.地下水氮浓度和形态变化与休耕前后土壤中DTN、NH_(4)^(+)-N、NO_(3)^(-)-N和地下水中p H、ORP、DO等因素密切相关.可见,休耕有效降低了农田土壤剖面氮累积,缓解了浅层地下水氮污染,有利于防止高原湖泊的水质恶化.

关键词：休耕氮储量浅层地下水土壤剖面抚仙湖

锦绣杜鹃热激转录因子基因RpHSFC1a的克隆及功能分析

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农业生物技术学报 2024年第6期32卷 1284-1296页

作者：申建双胡玥李雪芹程和丰金松恒浙江农林大学暨阳学院杭州职业技术学院

杜鹃花(Rhododendron)具有极高的观赏价值、经济价值和药用价值，而目前栽培的大多数杜鹃优良品种的耐热性较差，温度的升高会严重影响其正常生长发育。热激转录因子(heat stress transcription factors, HSFs)在植物热激应答或耐热性... 详细信息

杜鹃花(Rhododendron)具有极高的观赏价值、经济价值和药用价值，而目前栽培的大多数杜鹃优良品种的耐热性较差，温度的升高会严重影响其正常生长发育。热激转录因子(heat stress transcription factors, HSFs)在植物热激应答或耐热性调控中起核心作用。本研究克隆了锦绣杜鹃(Rhododendron×pulchrum) RpHSFC1a (GenBank No. OQ628046)和八氢番茄红素脱氢酶(phytoene desaturase)基因RpPDS(GenBank No. OQ628048)，以RpPDS为报告基因，烟草脆裂叶病毒(Tobacco rattle virus, TRV)为载体，构建锦绣杜鹃病毒诱导的基因沉默(virus-induced gene silencing, VIGS)体系，并对RpHSFC1a基因的生物信息学及其在响应高温胁迫中的功能进行了分析。通过表型观测、PCR和qPCR方法检测发现，TRV病毒可以侵染并在锦绣杜鹃叶片中复制和转移，当RpPDS基因被抑制表达后，锦绣杜鹃叶片会出现黄化现象，表明TRV病毒介导的基因沉默体系可以在锦绣杜鹃中应用。RpHSFC1a基因的CDS共891 bp，编码296个氨基酸，编码蛋白具有HSF＿DNA-bind superfamily保守结构域。RpHSFC1a蛋白预测为亲水蛋白和跨膜蛋白。系统发育分析表明，RpHSFC1a蛋白与君迁子(Diospyros lotus) HSFC1同源性最高，为75.8%。热胁迫下，RpHSFC1a基因显著高表达，RpHSFC1a基因沉默株系叶片的叶绿素参数Fv/Fm、PIABS和ETo/RC显著小于对照组；而DIo/RC显著高于对照组。表明RpHSFC1a基因的低表达可导致PSⅡ光能利用的能力降低，进而降低了锦绣杜鹃抵御高温胁迫的能力，推测RpHSFC1a基因参与锦绣杜鹃响应高温胁迫的调控。本研究可为杜鹃耐热性的研究提供理论参考，也为提高杜鹃高温胁迫耐受能力提供基因资源。

关键词：锦绣杜鹃病毒诱导的基因沉默(VIGS) 热激转录因子(HSFs) 叶绿素荧光基因功能分析

Behavioural analysis and dynamic simulation of the debris flow that occurred in Ganluo County(Sichuan, China) on 30 August 2020

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Journal of Mountain Science 2022年第6期19卷 1495-1508页

作者： LI Nuo-dong LIU Wei ZHAO jin-heng Chengdu Power Supply Company of State Grid Sichuan Electric Power Company Chengdu 610041China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Department of Water Hydropower and Construction Engineering Skill Training Center of State Grid Sichuan Electric Power CompanyChengdu 610000China

On August 30, 2020, a high-intensity storm that dropped 45.4 mm of rain in 5 hours hit the Heixiluo basin and triggered a landslide-generated debris flow event, causing fatalities and damage. The original source of the debris flow was a large slope collapse on a steep hillside. The fallen debris mass was enlarged through sediment entrainment and slope collapse and ultimately buried a bridge at the gully entrance. Approximately 6.9×10;m;of material, including sediments and collapsed slope deposits in the gullies, was entrained, and the maximum erosion depth reached 17 m. A geomorphological analysis was initially performed based on a detailed field investigation to recognize the liquid and solid sources of the debris flow and the areas subjected to deposition and erosion. A map of the erosiondeposition distribution was obtained based on preand post-event DEMs. Using the rainfall estimated by the nearest rain gauge and the solid source estimated by the DEMs, runoff and debris flow propagation was simulated using a liquid-solid two-phase model that considers the effects of runoff and entrainment. The similarity between the estimated and simulated deposition-erosion volumes was satisfactory. The behaviour of debris flows captured in the simulation is broadly in line with the main features of the observed event.

关键词： Debris flow Formation analysis Two-phase model Dynamic simulation

共生理论视角下5G通讯技术与体育产业融合发展研究

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湖北科技学院学报 2024年第3期44卷 96-101,114页

作者：徐超张晔罗佳金友恒咸宁职业技术学院健康管理学院湖北咸宁437100 湖北科技学院体育学院湖北咸宁437100 武汉市鲁巷中学湖北武汉430079

基于通讯技术与全民健身都是国家发展战略,从1G,2G,3G,4G,5G演进当作切入点,以网民分化为脉络,生物学“共生”为理论依托,通过文献资料、专家访谈、逻辑分析等方法,分析5G通讯技术与体育产业的融合基础,剖析二者融合困境与路径。擘画出... 详细信息

基于通讯技术与全民健身都是国家发展战略,从1G,2G,3G,4G,5G演进当作切入点,以网民分化为脉络,生物学“共生”为理论依托,通过文献资料、专家访谈、逻辑分析等方法,分析5G通讯技术与体育产业的融合基础,剖析二者融合困境与路径。擘画出体育智能大平台建设、提高运动体验、改变观赛体验、5G教学应用、运动损伤与急救等融合发展之路,助力健康中国与体育强国建设。

关键词：共生理论通讯技术体育融合

An adaptive graph embedding method for feature extraction of hyperspectral images based on approximate NMR model

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光电子快报:英文版 2023年第7期19卷 443-448页

作者： QIU Hong WANG Renfang jin heng WANG Feng College of Big Data and Software Engineering Zhejiang Wanli UniversityNingbo 315200China College of Information Shanghai Ocean UniversityShanghai 200120China

This paper introduces an approximate nuclear norm based matrix regression projection(ANMRP) model,an adaptive graph embedding method,for feature extraction of hyperspectral *** ANMRP utilizes an approximate NMR model to construct an adaptive neighborhood map between *** globally optimal weight matrix is obtained by optimizing the approximate NMR model using fast alternating direction method of multipliers(ADMM).The optimal projection matrix is then determined by maximizing the ratio of the local scatter matrix to the total scatter matrix,allowing for the extraction of discriminative *** results demonstrate the effectiveness of ANMRP compared to related methods.

关键词： approximate embedding matrix

Light-induced magnetic phase transition in van der Waals antiferromagnets

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 136-141页

作者： Jiabin Chen Yang Li Hongyu Yu Yali Yang heng jin Bing Huang Hongjun Xiang Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface PhysicsDepartment of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi Institute Shanghai 200030China Beijing Computational Science Research Center Beijing 100193China Department of Physics Beijing Normal UniversityBeijing 100193China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Control over magnetic properties by optical stimulation is not only interesting from the physics point of view,but also important for practical applications such as magneto-optical ***,based on a simple tight-binding(TB)model,we propose a general theory of light-induced magnetic phase transition(MPT)in *** the fact that the bandgap of the antiferromagnetic(AFM)phase is usually larger than that of the ferromagnetic(FM)one for a given system,we suggest that light-induced electronic excitation prefers to stabilize the FM state over the AFM one,and will induce an MPT from AFM phase to FM phase once a critical photocarrier concentration(αc)is *** theory has been confirmed by performing firstprinciples calculations on a series of 2D van der Waals(vd W)***,a linear relationship betweenαc and the intrinsic material parameters is obtained,in agreement with our TB model *** general theory paves a new way to manipulate 2D magnetism with high speed and superior resolution.

关键词： first-principles calculation density functional theory two-dimensional materials magnetic phase transition

天然气输气站控排闸阀失效分析与泄漏路径仿真

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全面腐蚀控制 2024年第3期38卷 51-58页

作者：胡恒进贾海平石磊王大为郝瑾尹志福陕西燃气集团有限公司陕西西安710016 陕西燃气储运及综合利用工程研究中心陕西西安710016 陕西燃气集团富平能源科技有限公司陕西渭南711700 陕西省表面工程与再制造重点实验室陕西西安710065

本文主要通过对某天然气输气站控排闸阀开展了化学成分、金相组织、显微硬度、形貌特征等失效分析,以掌握其在天然气输送服役中的腐蚀和磨损情况。为进一步揭示其可能存在的失效机制,利用有限元分析方法对闸阀的阀套、阀芯等主要部件进... 详细信息

本文主要通过对某天然气输气站控排闸阀开展了化学成分、金相组织、显微硬度、形貌特征等失效分析,以掌握其在天然气输送服役中的腐蚀和磨损情况。为进一步揭示其可能存在的失效机制,利用有限元分析方法对闸阀的阀套、阀芯等主要部件进行建模和计算,探讨和揭示闸阀泄漏路径,为后期输气站闸阀内表面处理提供数据支撑。研究显示,阀套、阀芯、阀座的局部腐蚀损伤主要是由天然气中含有极微量H_(2)O、较高CO_(2)和微量H_(2)S等侵蚀性气体以及极少量沙土协同作用的冲刷腐蚀引起。

关键词：阀套阀芯腐蚀磨损泄漏有限元分析