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Science China Technological Sciences 2024年

作者： MA Hao HAO TianZe MA JiChao sun zhenhao LI Xiang LIU YiBo XIAO HuaPing LIU ShuHai College of Mechanical and Transportation Engineering China University of Petroleum-Beijing Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology)

Motion performance, including movement speed, adaptability to various environments, and load-carrying capability, is crucial for soft crawling robots, tasked with field exploration and the transporting material in often complex and unstructured environments. A wide variety of soft crawling robots, which are driven by electricity [1], chemical power [2], and pressurized fluid [3] to move forward via cyclic deformation, have thus far been inspired by the mobile patterns of soft-bodied animals, such as worms [4],snake [5], octopus [6], etc. The performance of soft robots in terms of speed and load has developed impressively in recent years. Notably, there have been crawling robots with morphological adaptability [7], multimodality,and amphibious locomotion [8,9]. Despite impressive progress, there is still substantial work that remains in creating true systems that can match the speed, adaptability to various environments, and load-carrying capability, of natural organisms or motorized machines.

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轮胎/路表间水膜受力和排出特征及其受刻槽参数的影响分析

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中外公路 2024年第1期44卷 23-29页

作者：孙振浩陈俊山东省交通规划设计院集团有限公司山东济南250101 河海大学土木与交通学院江苏南京210098

为研究轮胎作用下水泥混凝土路表水膜受力特征及其受刻槽的影响,采用SolidWorks和Ansys WorkBench,构建了轮胎-水膜-路表有限元模型,基于CFD控制方程和流固耦合理论,分析轮胎作用下路表水膜流动规律以及水膜厚度、行车速度、刻槽宽度、... 详细信息

为研究轮胎作用下水泥混凝土路表水膜受力特征及其受刻槽的影响,采用SolidWorks和Ansys WorkBench,构建了轮胎-水膜-路表有限元模型,基于CFD控制方程和流固耦合理论,分析轮胎作用下路表水膜流动规律以及水膜厚度、行车速度、刻槽宽度、间距和方向对轮胎所受动水升力的影响。结果表明:轮胎迎水面所受动水升力随水膜厚度的增加而增大;当水膜厚度超过轮胎花纹深度后,动水升力增幅明显变大;增加路面刻槽宽度或减小刻槽间距,能够有效地降低轮胎所受的动水升力;在相同的刻槽参数下,路面横向刻槽的排水性能和对动水升力的降低幅度要优于纵向刻槽。

关键词：轮胎水膜路表动水升力刻槽

基于CANopen总线的嵌入式数控系统主站设计

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电子设计工程 2024年第19期32卷 71-75页

作者：孙振浩陈为青岛科技大学自动化与电子工程学院山东青岛266061

针对目前高端的数控系统价格高昂,开放性差,难以满足中小客户群体的需求,而小型的嵌入式数控系统主要以脉冲控制为主,存在接线复杂、容易受到干扰、加工效率低等问题。该文基于GRBL对总线式嵌入式数控系统进行了研究,引入拐角圆弧过渡... 详细信息

针对目前高端的数控系统价格高昂,开放性差,难以满足中小客户群体的需求,而小型的嵌入式数控系统主要以脉冲控制为主,存在接线复杂、容易受到干扰、加工效率低等问题。该文基于GRBL对总线式嵌入式数控系统进行了研究,引入拐角圆弧过渡、动态速度前瞻等轨迹规划算法优化加工路径。采用FreeRTOS实时操作系统,提高软件执行效率。基于CIA301和CIA402协议,采用CANopen工业现场总线实现对多轴电机的协同控制。实验结果表明,基于CANopen总线的嵌入式数控系统能够精确的跟踪加工轨迹,且相比于传统脉冲控制方式,接线数量减少了50%,有效提高了嵌入式数控系统的加工效率和可靠性。

关键词：嵌入式数控系统 CANopen 轨迹规划

变截面半圆通道内超临界二氧化碳热工水力性能研究

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热力发电 2024年第4期53卷 43-52页

作者：彭斌孙振豪朱兵国施佳宝张朋成兰州理工大学机电工程学院甘肃兰州730050

建立了不同半圆通道的数学和物理模型,并通过与实验数据的比较,验证了所建立模型的准确性。研究了超临界二氧化碳(S-CO_(2))在等截面半圆通道、渐扩型和渐缩型通道内的热工水力换热性能,并分析了不同通道和压力对S-CO_(2)在变截面半圆... 详细信息

建立了不同半圆通道的数学和物理模型,并通过与实验数据的比较,验证了所建立模型的准确性。研究了超临界二氧化碳(S-CO_(2))在等截面半圆通道、渐扩型和渐缩型通道内的热工水力换热性能,并分析了不同通道和压力对S-CO_(2)在变截面半圆通道内的热工水力性能的影响。结果表明:相较于均匀截面半圆通道,渐扩型通道恶化传热,渐缩型通道强化传热;入口和出口半径比为1.0:0.5的渐缩型半圆通道的总体换热系数最大提升了39.93%,流动传热综合性能评价因子PEC最大为1.346;当压力越靠近临界压力或热通量较低时,传热性能越高。最后,从场协同性和湍动能分布的角度解释了渐缩型变截面通道强化传热的原因。研究结果可为S-CO_(2)循环系统冷却器的设计与优化提供新的思路和理论指导。

关键词：超临界二氧化碳渐扩型通道渐缩型通道传热强化湍流场协同

2021—2022年春、秋季嵊泗列岛浮游植物群落状况及长期变化特征

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生态学报 2024年第13期44卷 5867-5881页

作者：詹琳江志兵杜伟孙振皓王德刚蒋雨露杜萍李宏亮曾江宁自然资源部第二海洋研究所自然资源部海洋生态系统动力学重点实验室杭州310012 浙江省海洋科学院自然资源部海洋空间资源管理技术重点实验室杭州310012 浙江省近海海洋工程环境与生态安全重点实验室杭州310012 自然资源部长三角海洋生态环境科学野外观测研究站舟山316021

为更好地了解嵊泗列岛海域在人类活动和气候变暖影响下的生态现状以及变化特征,于2020年秋季和2021年春季在该海域进行了浮游植物的拖网与水样采集及环境要素分析。水采样品中共检出浮游植物6门54属105种。其中,硅藻33属68种,甲藻14属30... 详细信息

为更好地了解嵊泗列岛海域在人类活动和气候变暖影响下的生态现状以及变化特征,于2020年秋季和2021年春季在该海域进行了浮游植物的拖网与水样采集及环境要素分析。水采样品中共检出浮游植物6门54属105种。其中,硅藻33属68种,甲藻14属30种,蓝藻、金藻和隐藻各2属2种,绿藻1属1种。春、秋季浮游植物主要优势种为骨条藻(Skeletonema spp.),并在秋季占据绝对优势(Y=0.975)。春季平均细胞丰度[(7.17±7.78)个/mL]明显低于秋季[(77.23±73.44)个/mL]。春季Shannon-Wiener多样性指数和Pielou均匀度指数均高于秋季。Spearman相关分析表明,浮游植物丰度与水温和透明度呈显著正相关,与盐度呈显著负相关。冗余分析显示,浮游植物群落组成与水温、营养盐密切相关。网采样品中共检出浮游植物4门46属94种,硅藻占比最大;春、秋季平均细胞丰度分别为838.17×10^(3)和19406.43×10^(3)个/m^(3)。与水样相比,骨条藻仍为主要优势种,且优势度更高;网采获得的秋季多样性指数和均匀度指数(分别为0.23和0.05)低于水采(分别为0.38和0.10)。将本次网采结果与1990年、2007年调查资料对比发现,嵊泗列岛春、秋季浮游植物群落组成发生了明显改变:丰度明显升高,硅甲藻占比无明显变化,暖水种种类数明显增加,骨条藻优势地位增强,多样性指数和均匀度指数下降。这可能与变暖与富营养化加剧相关。近30年来,溶解无机氮在春季无显著变化,但在秋季显著升高;活性磷酸盐浓度在春、秋季均显著降低;氮磷比在春、秋季均显著升高。浮游植物的变化特征较好地指示了嵊泗列岛海域在富营养化和气候变暖下的生态环境变化。

关键词：嵊泗列岛浮游植物环境因子富营养化长期变化

在线激光打孔脉冲持续时间对中支卷烟理化指标及其稳定性的影响研究

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中国烟草学报 2024年第3期30卷 44-50页

作者：李希强赵新玉张齐单凯李辉袁子豪孙振昊赵秀杰常纪恒王乐红塔辽宁烟草有限责任公司技术中心沈阳市苏家屯区南京南街1058号110100 中国烟草总公司郑州烟草研究院郑州高新技术产业开发区枫杨街2号450001

【目的】为中支卷烟在线激光打孔参数设计提供参考。【方法】分别采用显微镜和3D显微镜表征中支卷烟接装纸在线打孔的孔形态特征,考察在线打孔脉冲持续时间对中支卷烟理化指标及其稳定性的影响。【结果】①脉冲持续时间过短(≤47µs),... 详细信息

【目的】为中支卷烟在线激光打孔参数设计提供参考。【方法】分别采用显微镜和3D显微镜表征中支卷烟接装纸在线打孔的孔形态特征,考察在线打孔脉冲持续时间对中支卷烟理化指标及其稳定性的影响。【结果】①脉冲持续时间过短(≤47µs),出现孔未打透的情况,脉冲持续时间过长(≥90µs),出现椭圆孔的情况。②脉冲持续时间与孔直径、孔面积均呈线性正相关关系。③在线打孔脉冲持续时间与卷烟吸阻、滤嘴通风率和总通风率呈二次函数关系,且决定系数R2均在0.99以上;在线打孔脉冲持续时间与卷烟各项化学指标呈线性函数关系,且决定系数R2主要在0.96以上;卷烟水分释放量与打孔持续时间呈二次函数关系,决定系数为0.9767。④随着孔面积的升高及打孔个数的减小,卷烟的吸阻变化较小,均能保持相对稳定,卷烟总粒相物、烟碱、焦油、CO等释放量的标准偏差在脉冲持续时间适中(50~60μs)时比较小。

关键词：中支卷烟在线激光打孔孔形态通风率常规化学成分

A New Algorithm of Rain Type Classification for GPM Dual-Frequency Precipitation Radar in Summer Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第11期41卷 2093-2111页

作者： Yunfei FU Liu YANG zhenhao WU Peng ZHANG Songyan GU Lin CHEN sun NAN School of Earth and Space Sciences CMA-USTC Laboratory of Fengyun Remote SensingUniversity of Science and Technology of ChinaHefei 230026China Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research Institute of Heavy RainChina Meteorological AdministrationWuhan 430205China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China

In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar(DPR) suitable over the Tibetan Plateau(TP) was proposed by analyzing Global Precipitation Measurement(GPM) DPR Level-2 data in summer from 2014 to 2020. It was found that the DPR rain type classification algorithm(simply called DPR algorithm) has mis-identification problems in two aspects in summer TP. In the new algorithm of rain type classification in summer TP,four rain types are classified by using new thresholds, such as the maximum reflectivity factor, the difference between the maximum reflectivity factor and the background maximum reflectivity factor, and the echo top height. In the threshold of the maximum reflectivity factors, 30 d BZ and 18 d BZ are both thresholds to separate strong convective precipitation, weak convective precipitation and weak precipitation. The results illustrate obvious differences of radar reflectivity factor and vertical velocity among the three rain types in summer TP, such as the reflectivity factor of most strong convective precipitation distributes from 15 d BZ to near 35 d BZ from 4 km to 13 km, and increases almost linearly with the decrease in height. For most weak convective precipitation, the reflectivity factor distributes from 15 d BZ to 28 d BZ with the height from 4 km to 9 km. For weak precipitation, the reflectivity factor mainly distributes in range of 15–25 d BZ with height within 4–10 km. It is also shows that weak precipitation is the dominant rain type in summer TP, accounting for 40%–80%,followed by weak convective precipitation(25%–40%), and strong convective precipitation has the least proportion(less than 30%).

关键词： satellite precipitation radar rain type classification method Tibetan Plateau strong convective precipitation

The nodule-specific transcriptional repressor Top Hub 4 regulates nodule structure and nitrogen fixation capacity in soybean

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Journal of Genetics and Genomics 2024年第1期51卷 96-99页

作者： Kui Ge Qi Lv Shengcai Chen zhenhao Guo Yaqi Peng Yimian Chen Shiyong sun Xuelu Wang College of Life Science and Technology Huazhong Agricultural UniversityWuhanHubei 430070China State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityZhengzhouHenan 450046China The Academy for Advanced Interdisciplinary Studies Henan UniversityZhengzhouHenan 450046China Sanya Institute of Henan University SanyaHainan 572025China

Most leguminous plants establish symbiotic relationships with rhizobia to form root organs called nodules(Ferguson et al.,2010).Nodules are specialized organs containing bacterial symbionts,which can provide enormous amounts of fixed nitrogen to their plant hosts(Peoples et al.,2009).Soybean(Glycine max),an economically important grain and oil crop,forms symbiotic nitrogen-fixing nodules,which reduces the demand for chemical nitrogen fertilizers and promotes yield(Saito et al.,2014).Nodule development is spatiotemporally regulated by the action of a number of transcription factors(TFs).

关键词： specialized organs soybean

Spin relaxation induced by interfacial effects in GaN/Al_(0.25) Ga_(0.75) N heterostructures

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Fundamental Research 2021年第6期1卷 656-660页

作者： Shixiong Zhang Ning Tang Xiaoyue Zhang Xingchen Liu Lei Fu Yunfan Zhang Teng Fan zhenhao sun Fentao Wang Weikun Ge Bo Shen State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Frontiers Science Center for Nano-optoelectronics and Collaboration Innovation Center of Quantum Matter Peking UniversityBeijing 100871China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China

Spin relaxation induced by the interfacial effects in GaN/Al_(0.25) Ga_(0.75) N heterostructures was carefully investigated using a photon-energy-dependent time-resolved Kerr rotation *** existence of the interfacial localized states with potential fluctuations at the GaN/AlGaN heterointerface leads to photoluminescence peaks showing blue and S-shaped shifts owing to the excitation power and temperature,*** electrons in the localized states show a spin relaxation time longer than 1 ns because of the suppression of the D’yakonov-Perel’(DP)scattering,while the spin relaxation time of free electrons was approximately only 10 ps because of the giant Rashba spin-orbit coupling induced by the interfacial polarization field under the framework of the DP scattering ***,it is found that the high electron mobility at the heterointerface results in a long spin diffusion length of 300 nm at high temperatures,which is promising for the development of GaN-based spintronic devices.

关键词： GaN/AlGaN heterointerface Two-dimensional electron gas Interfacial localized state Spin dynamics Polarization field

Spin injection into heavily-doped n-GaN via Schottky barrier

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Journal of Semiconductors 2023年第8期44卷 57-61页

作者： zhenhao sun Ning Tang Shuaiyu Chen Fan Zhang Haoran Fan Shixiong Zhang Rongxin Wang Xi Lin Jianping Liu Weikun Ge Bo Shen State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Frontiers Science Center for Nano-optoelectronics&Collaboration Innovation Center of Quantum Matter Peking UniversityBeijing 100871China Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO) Chinese Academy of SciencesSuzhou 215123China International Center for Quantum Materials Peking UniversityBeijing 100871China

Spin injection and detection in bulk GaN were investigated by performing magnetotransport measurements at low temperatures.A non-local four-terminal lateral spin valve device was fabricated with Co/GaN Schottky *** spin injection efficiency of 21%was achieved at 1.7 *** was confirmed that the thin Schottky barrier formed between the heavily ndoped GaN and Co was conducive to the direct spin tunneling,by reducing the spin scattering relaxation through the interface states.

关键词： GaN spin injection Schottky barrier magnetoresistance