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Representation of the Stratospheric Circulation in CRA-40 Reanalysis:The Arctic Polar Vortex and the Quasi-Biennial Oscillation

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Advances in Atmospheric Sciences 2024年第5期41卷 894-914页

作者： zixu wang Shirui YAN Jinggao HU Jiechun DENG Rongcai REN Jian RAO Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The representation of the Arctic stratospheric circulation and the quasi-biennial oscillation(QBO)during the period 1981–2019 in a 40-yr Chinese global reanalysis dataset(CRA-40)is evaluated by comparing two widely used reanalysis datasets,ERA-5 and MERRA-2.CRA-40 demonstrates a comparable performance with ERA-5 and MERRA-2 in characterizing the winter and spring circulation in the lower and middle Arctic stratosphere.Specifically,differences in the climatological polar-mean temperature and polar night jet among the three reanalyses are within±0.5 K and±0.5 m s^(–1),respectively.The onset dates of the stratospheric sudden warming and stratospheric final warming events at 10 hPa in CRA-40,together with the dynamics and circulation anomalies during the onset process of warming events,are nearly identical to the other two reanalyses with slight differences.By contrast,the CRA-40 dataset demonstrates a deteriorated performance in describing the QBO below 10 hPa compared to the other two reanalysis products,manifested by the larger easterly biases of the QBO index,the remarkably weaker amplitude of the QBO,and the weaker wavelet power of the QBO period.Such pronounced biases are mainly concentrated in the period 1981–98 and largely reduced by at least 39%in 1999–2019.Thus,particular caution is needed in studying the QBO based on CRA-40.All three reanalyses exhibit greater disagreement in the upper stratosphere compared to the lower and middle stratosphere for both the polar region and the tropics.

关键词： CRA-40 ERA-5 MERRA-2 Arctic stratosphere the QBO

A potential-driven switch of activity promotion mode for the oxygen evolution reaction at Co_(3)O_(4)/NiO_(x)H_(y) interface

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eScience 2022年第4期2卷 438-444页

作者： wang wang zixu wang Youcheng Hu Yucheng Liu Shengli Chen Electrochemical Power Sources Key Laboratory Department of ChemistryWuhan UniversityWuhan430072China Wuhan University Testing Center Wuhan UniversityWuhan430072China

Co_(3)O_(4)spinel oxides have manifested promising activity toward the oxygen evolution reaction(OER)through effective modifications.For them to become top electrocatalysts,however,accurate accounts of the catalytic kinetics are essential to gain a deep understanding of the activity promotion mechanisms.Herein,we use a newly proposed kinetic model based on energetic span as the rate-determining term for the electrocatalytic reaction to throw light on the promotion mechanism of Co_(3)O_(4)interfaced with nickel hydroxides(NiO_(x)H_(y))for the OER.We find that depending on the electrode potential,the OER kinetics at the designed interface between Co_(3)O_(4)and NiO_(x)H_(y)are boosted in entirely different ways.As a result,the OER can occur at a lower onset potential as well as a low Tafel slope.This work emphasizes the benefit of using rational theoretical models for electrocatalyst design.

关键词： Oxygen evolution reaction Interface engineering Double exchange interaction Potential-driven switch of mechanism Energetic span

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说作业教研的内涵意蕴与结构探析

天津师范大学学报（基础教育版） 2024年第4期25卷 54-58页

作者：吴立宝王子续天津师范大学教育学部

随着“双减”政策的颁布,中小学作业正进行着重大改革,目标在于达到减负提质的效果。作业是连接课程、教学、学习和评价的关键环节,以作业为载体,以“说”为外化路径,以提升作业教学质量为目的,提出一种新型教研形式——说作业。研究认... 详细信息

随着“双减”政策的颁布,中小学作业正进行着重大改革,目标在于达到减负提质的效果。作业是连接课程、教学、学习和评价的关键环节,以作业为载体,以“说”为外化路径,以提升作业教学质量为目的,提出一种新型教研形式——说作业。研究认为,说作业结构框架包括说作业理念、说作业设计、说作业批改、说作业评讲、说作业反思,以语言为媒介展现作业教学全过程,在诊断、研讨、改进的过程中,可促使作业教学更加精细化、深入化、完备化,发挥说作业的理论价值与应用价值。

关键词：说作业 “双减”政策减负提质

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基于端壁L形凹槽的扩压叶栅角区分离控制

航空学报 2024年第10期45卷 82-110页

作者：王博吴艳辉黄令举王子胥西北工业大学动力与能源学院西安710129 陕西省航空发动机内流动力学重点实验室西安710129

为了解决用于控制压气机角区分离的旋涡发生器技术存在的不足,以高速扩压叶栅为研究对象,深入探究了利用端壁L形凹槽结构产生的流向涡抑制压气机角区分离的流动控制策略。首先,通过引入标准造型空间和函数叠合思想,为端壁L形凹槽结构发... 详细信息

为了解决用于控制压气机角区分离的旋涡发生器技术存在的不足,以高速扩压叶栅为研究对象,深入探究了利用端壁L形凹槽结构产生的流向涡抑制压气机角区分离的流动控制策略。首先,通过引入标准造型空间和函数叠合思想,为端壁L形凹槽结构发展了一种便捷且通用的参数化建模方法,并基于该方法开展了端壁L形凹槽的优化设计。通过比较原型叶栅和最优方案的流场仿真结果发现:端壁L形凹槽可以通过其产生的槽道分离涡来有效阻挡横向二次流,切断端壁低能流体向角区的供应,从而显著缓解角区反流、阻止角区分离伴生旋涡的形成,能够在宽广的攻角范围内显著改善叶栅的气动性能。对比不同Pareto最优方案的计算结果发现:槽道分离涡的旋涡强度决定了凹槽对横向二次流的控制效果以及引入附加流动损失和堵塞效应的严重程度,这是影响流动控制效果的关键因素。然后,将基于Sobol指标法的灵敏度分析方法与控制变量法相结合分析了设计参数对端壁L形凹槽流动控制效果的影响。结果表明:凹槽切向位置、凹槽深度、上游凹槽宽度和上游凹槽长度对凹槽的流动控制效果影响较为显著;其中凹槽切向位置主要影响槽道分离涡距离吸力面角区的远近,而后三者则主要影响槽道分离涡的旋涡强度。最后,基于以上分析,总结了端壁L形凹槽的设计参数选取原则。

关键词：扩压叶栅角区分离端壁L形凹槽槽道分离涡设计参数

Video Recognition for Analyzing the Characteristics of Vehicle–Bicycle Conflict

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Computers, Materials & Continua 2021年第11期69卷 2779-2791页

作者： Xingjian Xue zixu wang Linjuan Ge Lirong Deng Rui Song Neal Naixue Xiong College of Logistics and Traffic Central South University of Forestry and TechnologyChangsha410004HunanChina Department of Mathematics and Computer Science Northeastern State UniversityTahlequah74464OKUnited States

Vehicle–bicycle conflict incurs a higher risk of traffic accidents,particularly as it frequently takes place at intersections.Mastering the traffic characteristics of vehicle–bicycle conflict and optimizing the design of intersections can effectively reduce such conflict.In this paper,the conflict between right-turning motor vehicles and straight-riding bicycles was taken as the research object,and T-Analyst video recognition technology was used to obtain data on riding(driving)behavior and vehicle–bicycle conflict at seven intersections in Changsha,China.Herein,eight typical traffic characteristics of vehicle–bicycle conflict are summarized,the causes of vehicle–bicycle conflict are analyzed using 18 factors in three dimensions,the internal relationship between intersection design factors and traffic conflicts is explored,and the guiding of design optimization based on the width of bicycle lanes and the soft separation between vehicles and bicycles is discussed.The results showed that colored paved bicycle lanes were better,performing better at a width of 2.5 m compared to 1.5 m.However,the colored pavement was not suitable for the entire road and had to be set at the position,at which the trajectories of a bicycle and motor vehicle overlapped.Thus,a 2.5-m-wide bicycle lane provides good safety.However,there are still defects in the existing safety indicators,so it is necessary to develop new indicators to reflect real vehicle–bicycle conflict situations more comprehensively.

关键词： Vehicle-bicycle conflict video recognition technology bicycle lane width vehicle-bicycle separation method

单向陶瓷基复合材料C/SiC变角度顺逆磨的对比试验

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中国机械工程 2024年第2期35卷 235-243页

作者：张立峰王梓旭张旺通邓云飞隋翯郭志永中国民航大学航空工程学院天津300300

通过正十二边形磨削轨迹测试方法研究了单向C/SiC的磨削力和加工表面质量的影响机制。研究发现,相较于顺磨,逆磨的切向磨削力减小10%~25%,法向磨削力减小30%~50%,表面粗糙度减小25%~65%;纤维磨削角对磨削特性具有显著影响,顺纤维磨削时... 详细信息

通过正十二边形磨削轨迹测试方法研究了单向C/SiC的磨削力和加工表面质量的影响机制。研究发现,相较于顺磨,逆磨的切向磨削力减小10%~25%,法向磨削力减小30%~50%,表面粗糙度减小25%~65%;纤维磨削角对磨削特性具有显著影响,顺纤维磨削时,磨削力由大到小的纤维磨削角排序为60°、30°、90°、0°,逆纤维磨削时的排序为120°、90°、150°、180°;加工表面粗糙度Sa由大到小的纤维磨削角排序为0°、150°、120°、30°、60°、90°;C/SiC磨削加工时,材料的变形回弹效应较明显。对比了不同纤维磨削角下的表面微观形貌,提出了磨削材料去除模型。

关键词：复合材料磨削角度顺/逆磨材料去除模型

Integrated microdevice with a windmill-like hole array for the clog-free,efficient,and self-mixing enrichment of circulating tumor cells

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Microsystems & Nanoengineering 2022年第1期8卷 291-304页

作者： Hao Li Jinze Li Zhiqi Zhang Zhen Guo Changsong Zhang zixu wang Qiuquan Guo Chao Li Chuanyu Li Jia Yao Anran Zheng Jingyi Xu Qingxue Gao Wei Zhang Lianqun Zhou School of Biomedical Engineering(Suzhou) Division of Life Sciences and MedicineUniversity of Science and Technology of China260026 HefeiChina CAS Key Lab of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of Sciences215163 SuzhouChina Ji Hua Laboratory 528000 FoshanChina Department of Laboratory Medicine The Affiliated Suzhou Science and Technology Town HospitalNanjing Medical University215153 SuzhouChina Shenzhen Institute for Advanced Study University of Electronic Science and Technology of China518000 ShenzhenChina Suzhou CASENS Co. Ltd215163 SuzhouChina Jinan Guoke Medical Technology Development Co. Ltd250001 JinanChina

Circulating tumor cells(CTCs)have tremendous potential to indicate disease progression and monitor therapeutic response using minimally invasive approaches.Considering the limitations of affinity strategies based on their cost,effectiveness,and simplicity,size-based enrichment methods that involve low-cost,label-free,and relatively simple protocols have been further promoted.Nevertheless,the key challenges of these methods are clogging issues and cell aggregation,which reduce the recovery rates and purity.Inspired by the natural phenomenon that the airflow around a windmill is disturbed,in this study,a windmill-like hole array on the SU-8 membrane was designed to perturb the fluid such that cells in a fluid would be able to self-mix and that the pressure acting on cells or the membrane would be dispersed to allow a greater velocity.In addition,based on the advantages of fluid coatings,a lipid coating was used to modify the membrane surface to prevent cell aggregation and clogging of the holes.Under the optimal conditions,recovery rates of 93%and 90%were found for A549 and HeLa cells in a clinical simulation test of our platform with a CTC concentration of 20-100 cells per milliliter of blood.The white blood cell(WBC)depletion rate was 98.7%(n=15),and the CTC detection limit was less than 10 cells per milliliter of blood(n=6).Moreover,compared with conventional membrane filtration,the advantages of the proposed device for the rapid(2 mL/min)and efficient enrichment of CTCs without clogging were shown both experimentally and theoretically.Due to its advantages in the efficient,rapid,uniform,and clog-free enrichment of CTCs,our platform offers great potential for metastatic detection and therapy analyses.

关键词： logging free aggregation

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共轴刚性旋翼高速直升机配平策略优化设计

航空学报 2024年第9期45卷 254-271页

作者：王梓旭李攀鲁可朱振华陈仁良南京航空航天大学直升机动力学全国重点实验室南京210016 中国直升机设计研究所景德镇333001

最大巡航速度、最大平飞速度是共轴刚性旋翼高速直升机最重要的性能指标之一,其特殊的构型和工作方式导致其旋翼桨毂载荷问题突出。高速飞行俯仰姿态角、平尾安装角、横向周期变距差动、旋翼转速等配平状态和设计参数对需用功率、桨毂... 详细信息

最大巡航速度、最大平飞速度是共轴刚性旋翼高速直升机最重要的性能指标之一,其特殊的构型和工作方式导致其旋翼桨毂载荷问题突出。高速飞行俯仰姿态角、平尾安装角、横向周期变距差动、旋翼转速等配平状态和设计参数对需用功率、桨毂载荷、操稳特性等具有显著的非线性交叉耦合影响,在考虑飞行品质相关要求下开展了高速飞行配平策略优化设计方法研究,为获得飞行性能和桨毂载荷综合最优配平策略提供设计手段。基于共轴刚性旋翼高速直升机非线性飞行动力学模型,分析了不同配平策略设计参数对配平特性、稳定性、操纵性等影响规律;在此基础上,将配平策略设计问题描述为数学优化问题;为提高优化计算效率和降低优化失败风险,基于Kriging代理模型开展配平策略优化设计研究。优化结果表明:在最大巡航速度和最大飞行速度下,相比于基准配平策略,在最优功率配平策略下需用功率分别降低5.7%、6.9%;在最优桨毂力矩配平策略下桨毂力矩载荷分别降低55.6%、55.2%;在需用功率、桨毂力矩综合最优策略下需用功率分别降低1.8%、3.1%,桨毂力矩载荷分别降低49.4%、46.2%,验证了提出的配平策略优化设计方法的有效性。

关键词：共轴刚性旋翼高速直升机配平特性配平策略 Kriging模型优化设计

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高产虾青素的红法夫酵母菌株选育研究进展

中国畜牧杂志 2024年第5期60卷 12-17页

作者：孙克诚胡丹丹袁文华王令周静静王梓旭安佑生物科技集团股份有限公司江苏太仓215437

虾青素(3,3’-二羟基-4,4’-二酮基-β,β’-胡萝卜素)具有极强的抗氧化活性,还具有抗炎、抗凋亡、抗癌等多种生理功能。天然虾青素因其生物活性、利用率和安全性高于化学合成虾青素,更受消费者青睐。红法夫酵母能利用多种碳源且培养周... 详细信息

虾青素(3,3’-二羟基-4,4’-二酮基-β,β’-胡萝卜素)具有极强的抗氧化活性,还具有抗炎、抗凋亡、抗癌等多种生理功能。天然虾青素因其生物活性、利用率和安全性高于化学合成虾青素,更受消费者青睐。红法夫酵母能利用多种碳源且培养周期短,是理想的天然虾青素来源,但因生产中虾青素产量较低限制了红法夫酵母在工业上的应用。本文从育种、优化培养基及改造合成途径等方面综述了提高红法夫酵母虾青素产量的主要方法,以期为提高虾青素产量及红法夫酵母在工业生产上的应用提供理论依据。

关键词：红法夫酵母虾青素诱变育种工艺优化生物合成

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