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箱法在草地温室气体通量野外实验观测中的应用研究

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大气科学 2001年第1期25卷 61-70页

作者：杜睿王庚辰吕达仁孔琴心刘广仁万小伟张斌王艳芬季保明中国科学院大气物理研究所北京100029 中国科学院植物研究所北京100093

利用静态箱法采样，配以气相色谱仪法分析对草地Ｎ_２Ｏ、ＣＨ_４和ＣＯ_２温室气体通量进行了较系统的现场测量，同时对箱体内外温度进行同步观测。在对野外原位观测实验数据进行定量分析的基础上，论证了静态箱法对草原土壤－植被系... 详细信息

利用静态箱法采样，配以气相色谱仪法分析对草地Ｎ_２Ｏ、ＣＨ_４和ＣＯ_２温室气体通量进行了较系统的现场测量，同时对箱体内外温度进行同步观测。在对野外原位观测实验数据进行定量分析的基础上，论证了静态箱法对草原土壤－植被系统的Ｎ_２Ｏ、ＣＨ_４和ＣＯ_２通量测量的适用性和科学性，讨论了实验结果的可靠性。

关键词：静态箱法气相色谱仪法草地温室气体甲烷氧化亚氮二氧化碳

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禹城地区光合有效辐射的计算方法

山东气象 2009年第2期29卷 1-7页

作者：白建辉王庚辰刘恩民刘振民中国科学院大气物理研究所中层大气与全球环境探测开放实验室北京100029 中国科学院禹城综合试验站山东禹城251200

利用2005年7月—2006年10月在山东禹城对太阳辐射(包括光合有效辐射PAR、可见光辐射VIS、总辐射Q等)、气象要素等进行的4次综合观测资料,初步得到了PAR,VIS的日、季节变化特征并对其进行了分析,结果表明:各辐射的小时累计之比VIS/Q,PAR/... 详细信息

利用2005年7月—2006年10月在山东禹城对太阳辐射(包括光合有效辐射PAR、可见光辐射VIS、总辐射Q等)、气象要素等进行的4次综合观测资料,初步得到了PAR,VIS的日、季节变化特征并对其进行了分析,结果表明:各辐射的小时累计之比VIS/Q,PAR/Q,PAR/VIS相对稳定,其平均值分别为0.39,1.95(mol/MJ),4.97(mol/MJ),但它们均有明显的日、逐日、季节变化,并受水汽、气溶胶、云等因素的影响。同时建立了实际天气PAR,VIS的小时累计经验公式及其转换关系,计算值与观测值均比较接近。当考虑水汽和散射因子时,PAR,VIS的计算值与观测值的相对偏差分别为11.1%,10.6%。限于实际情况,可以只考虑水汽因子的作用来计算PAR和VIS的小时累计值,它们的相对偏差分别为13.3%,12.6%。水汽因子对于PAR,VIS的传输和计算具有重要作用。

关键词：太阳辐射光合有效辐射可见光辐射云散射因子

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基于ROS的智能车货物搬运系统

电子测试 2021年第21期32卷 88-89,23页

作者：孙义斐韩宇光赵桢淏王庚辰顾泽辰华东理工大学上海200237

随着生活节奏的加快,办公室成为人们工作的主要环境,而办公场景的复杂多变,工位通道狭窄则成为了货物运输的主要障碍,因此,实验设计一款货物搬运智能车。智能车系统由电源装置、摄像模块,承载车架,核心控制、驱动模块和动力装置够成。... 详细信息

随着生活节奏的加快,办公室成为人们工作的主要环境,而办公场景的复杂多变,工位通道狭窄则成为了货物运输的主要障碍,因此,实验设计一款货物搬运智能车。智能车系统由电源装置、摄像模块,承载车架,核心控制、驱动模块和动力装置够成。智能车利用雷达采集地图数据,核心模块对地图数据进行办公场景建模,根据需求进行路径规划,进而驱动智能车行驶,从而达到封闭场景运输货物的目的。

关键词：封闭场景建模路径规划自动化形式单片机

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极化复用的多功能反射型太赫兹超表面

太赫兹科学与电子信息学报 2024年第11期22卷 1238-1243页

作者：朱海亮谢胜琳王庚辰周怀仁于淼刘林西北工业大学电子信息学院陕西西安710129 北京航天计量测试技术研究所北京100076

现有的无源超表面功能较为单一,为增加调控太赫兹波的灵活性,提出一种极化复用的反射型超表面。该超表面能够实现波束偏转、双焦点聚焦、聚焦涡旋和远场成像等多种功能。在1 THz频率下,通过x极化和y极化波的分别入射,该超表面成功产生2... 详细信息

现有的无源超表面功能较为单一,为增加调控太赫兹波的灵活性,提出一种极化复用的反射型超表面。该超表面能够实现波束偏转、双焦点聚焦、聚焦涡旋和远场成像等多种功能。在1 THz频率下,通过x极化和y极化波的分别入射,该超表面成功产生2个偏转波束,并在焦平面上实现了双焦点聚焦。此外,该超表面在x极化和y极化波入射条件下,还分别实现了拓扑荷为l=+2的聚焦涡旋光束和远场成像。所设计的超表面显示出在不同极化波入射下灵活操纵太赫兹波的能力,展示了在太赫兹通信领域的潜在应用前景。

关键词：极化复用波束调控聚焦太赫兹超表面

One stone three birds:Ni-catalyzed asymmetric allenylic substitution of allenic ethers,hydroalkylation of 1,3-enynes and double alkylation of enynyl ethers

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Chinese Chemical Letters 2024年第8期35卷 282-287页

作者： Zhirong Yang Shan wang Ming Jiang gengchen Li Long Li Fangzhi Peng Zhihui Shao Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationSchool of Chemical Science and TechnologyYunnan Provincial Center for Research&Development of Natural Productsand State Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanYunnan UniversityKunming 650091China

The development of low-cost,earth-abundant and environmentally benign transition metal catalysts,which can catalyze multiple different types of asymmetric reactions,is an important objective in mod-ern asymmetric *** we demonstrate that a chiral Ni/P-Phos catalyst achieves three types of asymmetric reactions:allenylic substitution of racemic allenic ethers,1,4-hydroalkylation of prochiral 1,3-enynes and double alkylation of newly designed enynyl ether *** methods complement each other and produce various axially chiral allene derivatives bearing a pyrazolidine-3,5-dione unit,which is widely present in drugs and biologically active molecules with versatile pharmacological activities.

关键词： Nickel Asymmetric catalysis Allenylic substitution Hydroalkylation Double alkylation Allene 1,3-Enyne Pyrazolidine-3,5-dione

Au-Fe_(3)O_(4) dumbbell-like nanoparticles based lateral flow immunoassay for colorimetric and photothermal dual-mode detection of SARS-CoV-2 spike protein

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Chinese Chemical Letters 2024年第6期35卷 536-540页

作者： gengchen Guo Tianyu Zhao Ruichang Sun Mingzhe Song Hongyu Liu Sen wang Jingwen Li Jingbin Zeng College of Chemistry and Chemical Engineering and State Key Laboratory of heavy oil processing China University of Petroleum(East China)Qingdao 266580China Huangdao Customs of the People’s Republic of China Qingdao 266580China

Lateral flow immunoassay(LFIA)has become popular in laboratories,at-home testing,and medical diagnostics due to its minimal cost and ***,conventional test strips based on colloidal gold can only obtain qualitative or semi-quantitative results with low *** this work,AuFe_(3)O_(4) dumbbell-like nanoparticles were synthesized and used as the LFIA labelling marker for highly sensitive colorimetric-photothermal dual-mode detection of SARS-CoV-2 spike(S)*** unique dumbbell structure of Au-Fe_(3)O_(4) NPs makes it possible to combine the best features of both Au NPs and Fe_(3)O_(4) *** increased surface area of these NPs enhances their LSPR effect and photothermal effect,which achieves signal amplification to increase *** Au-Fe_(3)O_(4) NPs modified with S protein antibody could identify S protein in samples,which were recognized and accumulated on T-line by another antibody,generating color band for qualitative colorimetric *** T-line was irradiated by laser to obtain temperature change for quantitative detection of *** optimized conditions,the detection limit was 1.22 pg/m L,three orders of magnitude more sensitive than colorimetric ***,the approach was performed on SARS-CoV-2 pseudovirus samples and outperformed traditional colloidal gold *** LFIA platform exhibits significant promise for practical implementation,as it can satisfy the need for low-cost,high-sensitivity,and home-based quantitative detection for respiratory infectious diseases.

关键词： Au-Fe_(3)O_(4) dumbbell-like nanoparticles Photothermal effect LFIA S protein

A review on recent progress of non-stoichiometric SiOx anodes based on lithium ion batteries

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Progress in Natural Science:Materials International 2023年第1期33卷 47-54页

作者： gengchen Yu Jiayi Jing Chengzhe Li Qian Li Zhikai Yang Shuyu Yao Tao Li Xue Bai School of Materials Science and Engineering Shandong University of Science and Technology Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials(Ministry of Education) Shandong University

SiOxanode has attracted more and more attention due to its rich reserves and high theoretical capacity. However,the disadvantages of low initial Coulombic efficiency and large volume change limit its application. Therefore in this review, the research progress of SiOxanode will be summarized in detailed to demonstrate the various strategies adopted by researchers. Systematically introduction of the progress on preparation methods and modification strategies would be discussed, and the merits and challenges of various approaches will be highlighted as well, which provides valuable insights into the rational design and development of techniques to deal with the promising practical application of SiOxanode.

关键词： Lithium ion batteries SiOx anode Preparation methods Modification strategies

Pheromone based alternative route planning

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Digital Communications and Networks 2016年第3期2卷 151-158页

作者： Liangbing Feng Zhihan Lv gengchen Guo Houbing Song Shenzhen Institutes of Advanced Technology Chinese Academy ofSdences Shenzhen 518055 China Department of Computer Science University College London London WCIE 6EA United Kingdom Department of Electrical and Computer Engineering West Virginia University Montgomery WV 25136 USA Guilin University of Electronic Technology Guilin Guangxi 541004 China

In this work, we propose an improved alternative route calculation based on alternative figures, which is suitable for practical environments. The improvement is based on the fact that the main traffic route is the road network skeleton in a city. Our approach using nodes may generate a higher possibility of overlapping. We employ a bidirectional Dijkstra algorithm to search the route. To measure the quality of an Alternative Figures （AG）, three quotas are proposed. The experiment results indicate that the im- proved algorithm proposed in this paper is more effective than others.

关键词： PheromoneAlternative route planningBidirection DijkstraGISAG computation

Clipping discrete multi-tone for peak-power-constraint IM/DD optical systems

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Science China(Information Sciences) 2023年第5期66卷 227-237页

作者： Ji ZHOU Liangchuan LI Jiale HE Xiaofeng LU Yu BO Guanyu wang Yuanda HUANG gengchen LIU Yanzhao LU Shecheng GAO Yuanhua FENG Shancheng ZHAO Weiping LIU Changyuan YU Zhaohui LI Department of Electronic Engineering College of Information Science and Technology Jinan University Optical Research Department Huawei Technologies Co. Ltd. Department of Electronic and Information Engineering The Hong Kong Polytechnic University Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

High peak-to-average power ratio(PAPR) is a major drawback of discrete multi-tone(DMT) in peak-power-constraint(PPC) intensity-modulation/direct-detection(IM/DD) optical systems. Symmetric clipping operation is a frequently-used and practical method for mitigating the PAPR of the DMT ***, clipping noise is inevitably induced by the symmetric clipping operation, thereby deteriorating the system’s performance. In this paper, we study the statistical characteristics of the clipping noise in *** on the statistical characteristics, clipping-noise-cancellation(CNC) algorithms are proposed to mitigate the clipping noise in the clipping DMT systems. Theoretically, the clipping noise can be completely removed using the low-density-parity-check-assisted CNC algorithm(LDPC-assisted CNC algorithm). To verify the superiority of the clipping DMT with the CNC algorithm, we conduct an experiment with a50 Gb/s DMT system using 10G-class commercial devices for the scenario of PPC passive optical *** receiver sensitivity of the clipping DMT system with the CNC algorithm can reach-24 d Bm at a 20%soft-decision forward-error-correction limit, which is 2.5 d B higher than that of the DMT system without clipping operation. The clipping operation and the CNC algorithm are added after the original digital signal processing, thereby demonstrating the potential to efectively overcome the drawback in DMT signals and other high-PAPR signals.

关键词： discrete multi-tone peak-to-average power ratio peak-power constraint clipping-noise cancellation intensity-modulation/direct-detection optical systems