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桥面移动车辆横风气动特性数值模拟研究

振动与冲击 2025年第4期44卷 134-143页

作者：朱超张佳明冯玉祥马存明陈旭骏广东省公路建设有限公司黄茅海跨海通道管理中心广州510623 西南交通大学桥梁工程系成都610031 西南交通大学风工程四川省重点实验室成都610031 上海振华重工(集团)股份有限公司上海200125

车辆的横风效应是影响大跨度桥梁桥面行车安全性和舒适性的重要因素,并直接关系到桥梁的正常运营,而当前关于车辆气动特性的研究却大多针对地面场景。基于计算流体动力学(computational fluid dynamics,CFD)数值仿真平台,采用重叠动网... 详细信息

车辆的横风效应是影响大跨度桥梁桥面行车安全性和舒适性的重要因素,并直接关系到桥梁的正常运营,而当前关于车辆气动特性的研究却大多针对地面场景。基于计算流体动力学(computational fluid dynamics,CFD)数值仿真平台,采用重叠动网格技术同时模拟了集装箱货车在双箱梁桥面和地面上的真实运动,详细研究了桥面移动车辆在横风作用下的绕流流场和绕流气动力。结果表明:移动车辆在横风作用下的绕流特征主要与风速和车速所控制的合成风偏角有关;此外,与地面场景的模拟结果相比,桥面的存在显著降低了车辆的侧向力和横摆力矩,但在一定程度上增加了侧倾力矩,而且这种影响还与车辆在桥面上行驶的车道位置有关;最后,提出了桥面移动车辆气动力系数关于合成风偏角的经验公式以方便工程应用。

关键词：风-车辆-桥梁系统移动车辆气动特性计算流体动力学(CFD)数值模拟重叠网格

Effects of residual chlorine on the mortality, grazing and respiration of labidocera euchaeta (Copepoda)

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Acta Oceanologica Sinica 2011年第2期30卷 96-102页

作者： ma Zengling lIN Hongping GU Xiaolian XU Zhaoli Key and Open laboratory of marine and Estuary Fisheries （Ministry of Agriculture） East ChinaSea Fisheries Research Institute Chinese Academy of Fisheries Science Shanghai 200090 China Institute of life Science and Technology Zhanjiang Normal University Zhanjiang 524048 China

In this study,the authors investigated the effects of residual chlorine on mortality,grazing and respiration of labidocera euchaeta in *** grazing rate was evaluated by subtraction method of food concentration and respiration rate was measured using oxygen *** was found that the lethal effect of residual chlorine on *** increased with enhanced concentration and prolonged *** medium lethal concentration （lC 50 ） of chlorine for *** in 24 h was about 0.58 mg/l and the safe concentration was about 0.21 mg/***,the grazing and respiration of *** decreased by 32.6% and 18.9% when exposed to 0.2 mg/l residual chlorine for 4 *** indicated that the physiological activities of zooplankton could be suppressed by the residual chlorine less than the safety ***,both survival and physiological activities of the organisms living in the thermal （nuclear） power plant discharging waters should be considered when carrying out the ecological risks assessment.

关键词： copepod grazing labidocera euchaeta residual chlorine respiration zooplankton

Developmental quantitative genetic analysis of body weights and morphological traits in the turbot, Scophthalmus maximus

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Acta Oceanologica Sinica 2015年第2期34卷 55-62页

作者： WANG Xin'an ma Aijun ma Deyou Yellow sea.Fisheries Resea.ch Institute Chinese Academy of Fisheries Sciences/Key Laboratory of Sustainable Development of Marine Fisheries Ministry of Agriculture/Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology

In order to elucidate the genetic mechanism of growth traits in turbot during ontogeny, developmental genetic analysis of the body weights, total lengths, standard lengths and body heights of turbots was conducted by mixed genetic models with additive-dominance effects, based on complete diallel crosses with four different strains of Scophthalmus maximus from Denmark, Norway, Britain, and France. Unconditional genetic analysis revealed that the unconditional additive effects for the four traits were more significant than unconditional dominance effects, meanwhile, the alternative expressions were also observed between the additive and dominant effects for body weights, total lengths and standard lengths. Conditional analysis showed that the developmental periods with active gene expression for body weights, total lengths, standard lengths and body heights were 15–18, 15 and 21–24, 15 and 24, and 21 and 27 months of age, respectively. The proportions of unconditional/conditional variances indicated that the narrow-sense heritabilities of body weights, total lengths and standard lengths were all increased systematically. The accumulative effects of genes controlling the four quantitative traits were mainly additive effects, suggesting that the selection is more efficient for the genetic improvement of turbots. The conditional genetic procedure is a useful tool to understand the expression of genes controlling developmental quantitative traits at a specific developmental period（t-1→t） during ontogeny. It is also important to determine the appropriate developmental period（t-1→t） for trait measurement in developmental quantitative genetic analysis in fish.

关键词： Turbot(Scophthalmus maximus l.) growth developmental genetics genetic effect

Strange Quark Distribution and Corrections due to shadowing and Isospin Symmetry Breaking

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Chinese Physics letters 1996年第9期13卷 648-651页

作者： ma Bo-qiang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

The strange sea.quarks distributions of nucleons obtained by two global analyses based on available structure function data of muon and neutrino deep inelastic scatterings are different from the strange sea.quark distribution measured by the CCFR Collaboration from dimuon events in neutrino *** discuss possible contributions to this discrepancy from the nuclear shadowing in the deuteron and from the isospin symmetry breaking in the sea.between the neutron and the proton.

关键词： scattering quark symmetry

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不同品种养殖大黄鱼肌肉结构及蛋白组成分析

食品工业科技 2025年第4期46卷 316-323页

作者：马园郭全友郑尧孙威博杨柳宋晓燕上海理工大学健康科学与工程学院上海200093 中国水产科学研究院东海水产研究所农业农村部远洋与极地渔业创新重点实验室上海200090

为探究不同品种养殖大黄鱼的食用品质差异,本研究以‘东海1号’‘甬岱1号’‘富发1号’‘浙江传统品种’及‘宁德传统品种’为对象,对其肌肉结构及蛋白组成进行测定分析。结果表明,不同品种大黄鱼的基本营养成分存在一定差异,‘富发1号... 详细信息

为探究不同品种养殖大黄鱼的食用品质差异,本研究以‘东海1号’‘甬岱1号’‘富发1号’‘浙江传统品种’及‘宁德传统品种’为对象,对其肌肉结构及蛋白组成进行测定分析。结果表明,不同品种大黄鱼的基本营养成分存在一定差异,‘富发1号’肌肉粗蛋白含量显著高于其他4个品种,而‘浙江传统品种’的粗脂肪含量最低,仅有2.77%;‘甬岱1号’大黄鱼肌纤维密度最高,是‘宁德传统品种’大黄鱼肌纤维密度的1.43倍;5个品种大黄鱼的肌纤维横截面积由大到小排序为‘浙江传统品种’>‘宁德传统品种’>‘富发1号’>‘东海1号’>‘甬岱1号’,低场核磁共振也发现‘甬岱1号’不易流动水具有较小的弛豫时间;‘富发1号’大黄鱼肌肉中盐溶性蛋白含量最高,为‘东海1号’的1.29倍,5个品种大黄鱼水溶性蛋白含量在58.72~74.85 mg/g之间,而凝胶电泳结果表明不同品种大黄鱼的肌肉蛋白分子量分布无显著差异;5个品种大黄鱼肌肉的亮氨酸、赖氨酸、苯丙氨酸和酪氨酸含量均高于WHO/FAO标准。本研究从食品原料学角度系统分析了不同品种养殖大黄鱼的肌肉结构及蛋白组成差异,为后续良种选育和高质加工提供参考。

关键词：养殖大黄鱼品种蛋白组成肌肉结构肌纤维

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Opposing Trends of Winter Cold Extremes over Eastern Eurasia and North America under Recent Arctic Warming

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Advances in Atmospheric Sciences 2020年第12期37卷 1417-1434页

作者： Shuangmei ma Congwen ZHU State Key laboratory of Severe Weather and Institute of Climate System Chinese Academy of Meteorological SciencesBeijing 100081China

Under recent Arctic warming,boreal winters have witnessed severe cold surges over both Eurasia and North America,bringing about serious social and economic ***,we investigated the changes in daily surface air temperature(SAT)variability during the rapid Arctic warming period of 1988/89–2015/16,and found the daily SAT variance,mainly contributed by the sub-sea.onal component,shows an increasing and decreasing trend over eastern Eurasia and North America,*** cold extremes(defined as days with daily SAT anomalies below 1.5 standard deviations)dominated the increase of the daily SAT variability over eastern Eurasia,while decreasing cold extremes dominated the decrease of the daily SAT variability over North *** circulation regime of cold extremes over eastern Eurasia(North America)is characterized by an enhanced high-pressure ridge over the Urals(Alaska)and surface Siberian(Canadian)*** data analyses and model simulations show the recent strengthening of the high-pressure ridge over the Urals was associated with warming of the Barents–Kara sea. in the Arctic region,while the high-pressure ridge over Alaska was influenced by the offset effect of Arctic warming over the East Siberian–Chukchi sea. and the Pacific decadal oscillation(PDO)–like sea.surface temperature(SST)anomalies over the North *** transition of the PDO-like SST anomalies from a positive to negative phase cancelled the impact of Arctic warming,reduced the occurrence of extreme cold days,and possibly resulted in the decreasing trend of daily SAT variability in North *** multi-ensemble simulations of climate models confirmed the regional Arctic warming as the driver of the increasing SAT variance over eastern Eurasia and North America and the overwhelming effect of SST forcing on the decreasing SAT variance over North ***,the regional response of winter cold extremes at midlatitudes to the Arctic warming could be different due to the dis

关键词： daily surface air temperature variability extreme cold days Arctic warming eastern Eurasia North America

Summer Extreme Precipitation in the Key Region of the Sichuan-Tibet Railway

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Advances in Atmospheric Sciences 2023年第5期40卷 843-855页

作者： Jiali ma Xiuping YAO State Key laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China China Meteorological Administration Training Centre Beijing 100081China

The Sichuan-Tibet Railway,mainly located in the southeastern Qinghai-Tibet Plateau,is affected by summertime extreme precipitation(SEP).Using daily rain-gauge observations and ERA5 reanalysis data for the summers of 1979-2020,the spatiotemporal distribution characteristics of SEP in the key region of the Sichuan-Tibet Railway(28°-33°N,90°-105°E,hereafter KR)are revealed,and the mechanism for SEP amount(SEPA)variation in the KR is *** results show that SEPA in the KR contributes nearly 30%to the total summer *** differences are evident in SEP,justifying thresholds higher in the plateau-dominated central-western KR(CWKR)and lower in the basindominated eastern KR(EKR).In addition,SEP in the CWKR is less intense but more frequent than SEP in the *** 1979-2020,the SEPA in the KR increased slightly while the SEPA in the CWKR increased significantly and peaked in the last *** anticyclonic circulation(AC)anomalies dominate the 500 hPa pattern over the Bay of Bengal and Mongolia,the southerly flow and cyclonic shear over the southeastern plateau will be strengthened,favoring more SEPA in the *** an AC anomaly dominates the 500 hPa pattern over the Bohai sea.the low-level easterly wind over the basin will be strengthened,favoring more SEPA in the *** strengthening of the ascent,water vapor convergence,and convective instability is conducive to more SEPA in the *** results deepen the understanding of the characteristics and the physical mechanisms responsible for extreme precipitation in the KR.

关键词： summertime extreme precipitation distribution characteristics variation mechanism

An Empirical Model of Tropical Cyclone Intensity Forecast in the Western North Pacific

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Journal of Meteorological Resea.ch 2022年第5期36卷 691-702页

作者： Chen ma Tim lI Jiangsu Meteorological Observatory Jiangsu Meteorological BureauNanjing 210019China Key laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)NanjingUniversityof Information Science&TechnologyNanjing210044China International Pacific Resea.ch Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversityofHawaiiHI96822USA Key laboratory of Transportation Meteorology China Meteorological AdministrationNanjing 210019China

The relative impact of environmental parameters on tropical cyclone(TC) intensification rate(IR) was investigated through a box difference index(BDI) method, using TC best track data from Joint Typhoon Warning Center and environmental fields from the NCEP final analysis data over the western North Pacific(WNP) during 2000–*** are total 6307 TC samples with a 6-h interval, of which about 14% belong to rapid intensification(RI) category. The analysis shows that RI occurs more frequently with higher environmental sea.surface temperature, higher oceanic heat content, and lower upper-tropospheric temperature. A moderate easterly shear is more favorable for TC intensification. TC intensification happens mostly equatorward of 20°N while TC weakening happens mostly when TCs are located in the northwest of the basin. Mid-tropospheric relative humidity and vertical velocity are good indicators separating the intensification and non-intensification groups. A statistical model for TC intensity prediction was constructed based on six environmental predictors, with or without initial TC intensity. Both models are skillful based on Brier skill score(BSS) relative to climatology and in comparison with other statistical models, for both a training period(2000–2018) and an independent forecast period(2019–2020).

关键词： tropical cyclone rapid intensification prediction model

Spatiotemporal Trends and Ecological Determinants in Population by Elevation in China Since 1990

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Chinese Geographical Science 2021年第2期31卷 248-260页

作者： ma Chaoqun HE Yanfen College of Earth Science and Resources Chang’an UniversityXi’an 710054China Yellow River Institute of shaanxi Province College of Urban and Environment SciencesNorthwest UniversityXi’an 710127China

It is very important to understand the ecological and socio-economic factors in population distribution and their changes over time for the compilation of regional development planning and the guidance of rational population *** surface-based population data for China from 1990 to 2015,the national distribution and dynamics of the human population by elevation are quantified based on 1-km cell-size gridded distribution datasets and 1-km cell-size DEM(digital elevation model).A geographical detector model is used to quantitatively analyze the dominant role of natural geographical factors,such as topography and climate,on the spatial distribution of *** show that:1)the population size and density decrease rapidly with elevation below 1000 m above the sea.level,and the gap in population density between low-altitude areas and high-altitude areas increases with time because of the continuous growth of population density in low-altitude areas;2)the distribution of the population can be divided into five steps according to integrated population density(IPD),in proportions of 43∶35∶21∶1∶0,and that these proportions have remained stable over the last 25 yr;3)the basic pattern of population spatial distribution is determined by natural geographical environment factors,such as topography,climate,geomorphology,and their interactions;and 4)the development of society and the economy are the driving forces for the dynamic change in the population distribution during the study period,with the distribution pattern and dynamics of population by altitude in China providing a comprehensive reflection of various geographical elements on different spatial scales.

关键词： population distribution vertical distribution hypsographic demography geographical detector model China