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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 735-741页

作者： Minqi SHENG chenkai lv Lan HONG Mingwang SHAO Kang WAN Fan lv School of Iron and Steel Soochow University Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University

In this paper, Ni-Co coatings were electrodeposited onto carbon steel substrates with the aid of ultrasonic agitation. The coatings were analyzed by energy dispersive X-ray analysis （EDX）, X-ray diffraction analysis （XRD） and scanning electron microscopy （SEM）. The effects of the ultrasonic frequency on the roughness, hardness and corrosion resistance of the Ni-Co coatings were also investigated. The results indicated that the increase of the ultrasonic frequency from 20 to 120 kHz reduced the Ni content and the grain size of Ni-Co coatings. Moreover, the phase structure of the electrodeposited coatings was influenced by the ultrasonic frequency. Under 55 kHz ultrasonic agitation, the Ni-Co coating was single fcc phase and showed the finest roughness and the strongest corrosion resistance in 5 wt.% NaCl solution at the ambient temperature. Under ultrasonic agitation with frequency of 90 kHz, the coating was a mixture of fcc and hcp structure and showed the maximal hardness of about 420 HV. Therefore, ultrasonic agitation helped decrease the roughness, and enhance hardness and corrosion resistance of Ni-Co coatings.

关键词： Ni-Co alloys Coatings Electrodeposition Ultrasound Hardness Corrosion

Experimental Investigation of Wave-Current Loads on a Bridge Shuttle-Shaped Cap–Pile Foundation

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1565-1592页

作者： chenkai Hong Zhongda Lyu Fei Wang Zhuo Zhao Lei Wang College of Science and Technology Ningbo UniversityNingbo315300China Engineering Research Center of Industrial Construction in Civil Engineering of Zhejiang Province Ningbo University of TechnologyNingbo315211China

To scrutinize the characteristics of wave-current loads on a bridge shuttle-shaped cap–pile foundation,a 1:125 test model was considered in a laboratory *** inline,transverse and vertical wave–current forces acting on the shuttle-shaped cap-pile group model were measured considering both random waves and a combination of random waves with a *** experimental results have shown that the wave-current forces can be well correlated with the wave height,the wavelength,the current velocity,the incident direction and the water level in the marine *** increase in the current velocity can lead to a sharp increase in the inline and transverse wave-current forces,while the vertical wave-current force ***,the wave-current forces are particularly strong when a combination of high tide,strong wave and strong current is considered.

关键词： Shuttle-shaped cap-pile foundation wave-current force wave flume experiment sea-crossing bridge

Numerical Investigations on Dynamic Stall Characteristics of a Finite Wing

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 444-457页

作者： JING Simeng CAO chenkai GAO Yuan ZHAO Qijun ZHAO Guoqing National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching ***,CFD methods are developed to calculate the aerodynamic characteristics of *** URANS equations are solved using a finite volume method,and the two-equation k-ωshear stress transport(SST)turbulence model is employed to account for viscosity ***,the CFD methods are used to simulate the aerodynamic characteristics of both a static,rectangular wing and a pitching,tapered wing to verify their effectiveness and *** numerical results show good agreement with experimental ***,the static and dynamic characteristics of the finite wing are computed and *** results reveal significant 3D flow structures during both static and dynamic stalls,including wing tip vortices,arch vortices,Ω-type vortices,and ring *** phenomena lead to differences in the aerodynamic characteristics of the finite wing compared with a 2D ***,the finite wing has a smaller lift slope during attached-flow stages,higher stall angles,and more gradual stall *** separation initially occurs in the middle spanwise section and gradually spreads to both *** aerodynamic damping,the inboard sections mainly generate unstable ***,sections experiencing light stall have a higher tendency to produce negative damping compared with sections experiencing deep dynamic stall.

关键词： finite wing dynamic stall aerodynamic damping 3D effects

Analysis of Low Fertility Rates in Advanced Economies

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Management Studies 2024年第4期12卷 252-254页

作者： LI chenkai Nanjing Dongshan Foreign Language School NanjingChina

In economics,opportunity cost means the maximum value of choosing one behavior over others in the situation where resources are limited(Parkin,2016).In the process of making reproductive decision,opportunity cost reveals the trade-off between time,resources,and economic benefits that individuals face when choosing to have children or *** this process,the technological changes make the paths of career development diverse and rapidly changing,remarkably increasing the opportunity cost of childbirth and *** leads to individuals more inclined to postpone or reduce childbirth when balancing their careers and families,thereby resulting in low fertility rates in developed economies.

关键词： low fertility advanced economies technological changes

Synergistic enhancement of chemotherapy for bladder cancer by photothermal dual-sensitive nanosystem with gold nanoparticles and PNIPAM

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Chinese Chemical Letters 2024年第8期35卷 471-474页

作者： Xiangqian Cao chenkai Yang Xiaodong Zhu Mengxin Zhao Yilin Yan Zhengnan Huang Jinming Cai Jingming Zhuang Shengzhou Li Wei Li Bing Shen Department of Urology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of Nanomedicine&Shanghai Key Lab of Cell Engineering Naval Medical UniversityShanghai 200433China

Bladder cancer is a common malignant tumor of the urinary system with the potential to be treated by nano drug delivery *** current work describes the synthesis and characterization of a novel nanomaterial to construct a nano-carrier based on 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatecholine(POPC)loaded doxorubicin(DOX)and embedded with gold nanoparticles and poly(N-isopropyl acry-lamide)(PNIPAM)(GNPS@PNIPAM-POPC-DOX,GPPD).The dual-sensitive nanosystem gives simultaneous photothermal treatment and chemotherapy for bladder *** vitro and in vivo properties were as-sessed using bladder cancer cell lines and mice and GPPD system distribution,tumor inhibition,and biocompatibility are *** system had favorable stability,low biological toxicity,controlled re-lease efficiency,photothermal synergistic action,efficient photothermal transition,and favorable tumor suppressive *** a result,GPPD is a potential therapeutic approach for bladder cancer.

关键词： Doxorubicin Gold nanoparticles Thermosensitive polymer Photothermal therapy Bladder cancer

积极老龄化背景下的老年人再就业权利法律保护路径研究

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河南财经政法大学学报 2021年第2期36卷 63-72页

作者：徐智华吕晨凯中南财经政法大学湖北武汉430073 中南财经政法大学劳动法与社会保障法研究中心湖北武汉430073

目前,积极老龄化已成为我国的国家战略,老年人再就业作为积极老龄化的重要策略对我国应对人口老年化问题有着重要作用。老年人再就业是我国的发展战略要求,是老年人作为劳动者享有劳动权利的具体表现,也是平等和反歧视原则的内在要求。... 详细信息

目前,积极老龄化已成为我国的国家战略,老年人再就业作为积极老龄化的重要策略对我国应对人口老年化问题有着重要作用。老年人再就业是我国的发展战略要求,是老年人作为劳动者享有劳动权利的具体表现,也是平等和反歧视原则的内在要求。我国老年人再就业在不同行业中存在差异,法定退休年龄以及社会保险体制与劳动关系的二元分割是我国老年人再就业的重大阻碍。因此,应适当延迟法定退休年龄并给予劳动者一定的退休自主权,同时对基本养老保险金给付予以区别对待。应当在现有法律框架内进行专项立法,以分层保护的理念对老年人再就业的劳动基准采取不同程度的区分。需要各部门协同促进,在税收、贷款、补贴上对老年人再就业给予多方面优惠。

关键词：老年人再就业权益保护积极老龄化分层保护

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基于多源遥感的桐乡市水系格局演变研究

浙江农林大学学报 2024年第2期41卷 419-428页

作者：徐晨凯王珂黄璐浙江大学环境与资源学院浙江杭州310058 浙江大学新农村发展研究院浙江杭州310058

【目的】浙江省桐乡市水系受人类活动干扰巨大,定量评估桐乡市水系的演变过程对其未来水系优化布局与城市可持续发展具有重要意义。【方法】基于1975、1998、2005、2012、2016、2019年6期多源遥感影像与土地利用调查数据,采用目视解译... 详细信息

【目的】浙江省桐乡市水系受人类活动干扰巨大,定量评估桐乡市水系的演变过程对其未来水系优化布局与城市可持续发展具有重要意义。【方法】基于1975、1998、2005、2012、2016、2019年6期多源遥感影像与土地利用调查数据,采用目视解译方式获取水系数据,使用河网水系指标、景观格局指数、空间叠加分析等方法定量研究桐乡市河流和池塘的数量、结构、形态、功能、空间分布变化规律与原因。【结果】①桐乡市河流长度和面积在2005年前保持增加,在快速城镇化时期剧烈衰减,到2016年后快速恢复。Ⅰ级河流持续增长,支流在各个时间阶段变化显著。②河网密度、支流发育系数、分形维度在整个过程中先增加再减小最后快速增加,河流水面率持续上升但在高速城镇化时期增速明显滞缓,河网环度与实际结合度不断波动并在2016年达到峰值。③河网密度在近郊与远郊的变化远大于市区。在2005年前,河流水面率变化市区>远郊>近郊,开始快速城镇化后,市区>近郊>远郊。远郊的支流发育系数变化最不显著。④桐乡市池塘面积同样经历了先增加后减小最后快速增加的过程,结构组成不断变化,养殖坑塘的激增是池塘面积改变的主要因素。池塘形态在发展中逐渐规整,分布先聚集后离散最后重新连片,并在西部远郊区域产生大规模聚集。【结论】桐乡市不同时期水系变化受城市发展政策影响巨大,具有明显的阶段性,造成地方水系变化的主要原因包括城镇化发展、农业结构调整、生态治理与修复,与同类型平原水网城市变化特征存在异同。

关键词：多源遥感水系格局时空演变桐乡市

不同中国传统运动对肥胖人群健康益处的系统评述

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冰雪体育创新研究 2024年第6期 191-193页

作者：马晨恺南昌大学体育学院江西南昌330000

该文系统回顾了近年来中国传统运动在治疗单纯性肥胖方面的临床进展,并讨论了其在治疗单纯性肥胖方面的具体优势,重点介绍几种具有代表性的中国传统运动,即太极拳、八段锦、易筋经、五禽戏、少林内功和六字决等,这些运动在治疗单纯性肥... 详细信息

该文系统回顾了近年来中国传统运动在治疗单纯性肥胖方面的临床进展,并讨论了其在治疗单纯性肥胖方面的具体优势,重点介绍几种具有代表性的中国传统运动,即太极拳、八段锦、易筋经、五禽戏、少林内功和六字决等,这些运动在治疗单纯性肥胖方面均表现出各自的特点和临床有益效果。为优化这些中国传统运动的临床治疗效果,需要根据不同肥胖人群的特点,寻求最适合的运动或组合运动,以提高减肥效率,减少运动损伤,巩固治疗效果。未来应进一步探索这些中国传统运动的作用机制。

关键词：中国传统运动肥胖健康研究进展

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基于DSP的多普勒雷达测速仪的设计与实现

数据通信 2024年第3期 19-24页

作者：耿晨凯宁波大学信息科学与工程学院浙江宁波315211

为了进一步解决当前基于单片机的交通测速仪中存在的电路复杂、测量精度低、反应速度慢等问题,本文基于多普勒效应和快速傅里叶变换(FFT)原理,提出一种基于DSP芯片TMS320F2812的多普勒雷达测速仪,该测速仪以TMS320F2812为主控核心,对运... 详细信息

为了进一步解决当前基于单片机的交通测速仪中存在的电路复杂、测量精度低、反应速度慢等问题,本文基于多普勒效应和快速傅里叶变换(FFT)原理,提出一种基于DSP芯片TMS320F2812的多普勒雷达测速仪,该测速仪以TMS320F2812为主控核心,对运动车辆产生的多普勒频移信号进行处理,进而计算其行驶速度。实验结果表明该测速仪测速效果与预期结果相符,可以在一定程度上缓解上述问题。

关键词：雷达测速仪 TMS320F2812 快速傅里叶变换多普勒效应

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深部煤层开采矿井防治水技术研究

新疆钢铁 2024年第1期 61-63页

作者：刘宸铠中煤科工西安研究院(集团)有限公司陕西西安710077

深部煤层开采由于地质条件复杂,常伴随着大量的地下水涌入,严重影响生产安全。通过分析深部煤层开采中水害的发生机理,总结现有的水害预测技术方法,重点研究了填充开采、设置防水闸门、煤层底板加固注浆等深部煤层开采矿井的防治水技术... 详细信息

深部煤层开采由于地质条件复杂,常伴随着大量的地下水涌入,严重影响生产安全。通过分析深部煤层开采中水害的发生机理,总结现有的水害预测技术方法,重点研究了填充开采、设置防水闸门、煤层底板加固注浆等深部煤层开采矿井的防治水技术。综合运用各项防治水技术,可以有效控制和降低深部煤层开采中的水害危险,保证矿井安全高效开采。

关键词：深部煤层开采矿井防治水技术