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Chemical characteristics of PM_(2.5) during haze episodes in the urban of Fuzhou,China

Particuology 2013年第3期11卷 264-272页

作者： Fuwang Zhang Lingling Xu Jinsheng Chen Xiaoqiu Chen Zhenchuan Niu tong lei Chunming Li Jinping Zhao Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences Graduate University of Chinese Academy of Sciences Environmental Monitoring Center of Fujian Environmental Monitoring Center of Guangdong

Atmospheric fine particles （PM2.5） were collected in this study with middle volume samplers in Fuzhou, China, during both normal days and haze days in summer （September 2007） and winter （january 2008）. The concentrations, distributions, and sources of polycyclic aromatic hydrocarbons （PAHs）, organic carbon （OC）, elemental carbon （EC）, and water soluble inorganic ions （WSIls） were determinated. The results showed that the concentrations of PM2.s, PAHs, OC, EC, and WSIIs were in the orders of haze 〉 normal and winter〉 summer. The dominant PAHs of PM2.s in Fuzhou were Fluo, Pyr, Chr, BbF, BkF, BaP, BghiP, and IcdP, which represented about 80.0% of the total PAHs during different sampling periods. The BaPeq concentrations of ^-~PAHs were 0.78, 0.99, 1.22, and 2.43 ng/m3 in summer normal, summer haze, winter normal, and winter haze, respectively. Secondary pollutants （SO42 , NO3 , NH4＊, and OC） were the major chemical compositions of PM2.5, accounting for 69.0%, 55.1%, 63.4%, and 64.9% of PM2.s mass in summer normal, summer haze, winter normal, and winter haze, respectively. Correspondingly, secondary organic carbon （SOC） in Fuzhou accounted for 20.1%, 48.6%, 24.5%, and 50.5% of OC. The average values of nitrogen oxidation ratio （NOR） and sulfur oxidation ratio （SOR） were higher in haze days （0.08 and 0.27） than in normal days （0.05 and 0.22）. Higher OC/EC ratios were also found in haze days （5.0） than in normal days （3.3）. Correlation analysis demonstrated that visibility had positive correlations with wind speed, and neg- ative correlations with relative humidity and major air pollutants. Overall, the enrichments of PM2.5, OC, EC, SO42 ,andNO3 promoted haze formation. Furthermore, the diagnostic ratios of IcdP/（IcdP ＋ BghiP）, lcdP/BghiP, OC/EC, and NO3 /SO42 indicated that vehicle exhaust and coal consumption were the main sources of pollutants in Fuzhou.

关键词： Fine particles Haze Polycyclic aromatic hydrocarbons Organic carbon Elemental carbon Water soluble inorganic ions

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Two-dimensional materials-based integrated hardware

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Science China(Information Sciences) 2023年第6期66卷 5-25页

作者： Zhuiri PENG Runfeng LIN Zheng LI Langlang XU Xiangxiang YU Xinyu HUANG Wenhao SHI Xiao HE Xiaohan MENG lei tong Xiangshui MIAO lei YE School of Integrated Circuit Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology Hubei Yangtze Memory Laboratories Department of Electronic Engineering and Materials Science and Technology Research Center The Chinese University of Hong Kong State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of Sciences

In recent years, two-dimensional(2D)materials-based fundamental preparing process such as high-quality wafer-level single crystal thin film synthesis technology and high-performance electrode preparing technology has developed rapidly. In addition, the integrated application prospect of 2D materials has been preliminarily verified, owing to the flat and clean interface between 2D materials and substrates. From the perspective of electronics and optoelectronics based on 2D materials, this paper will summarize the recent studies of integrated circuit hardware, integrated optoelectronic hardware, and hetero-integrated hardware,showing their advantages and potential application.

关键词： two-dimensional materials integrated circuit integrated sensor integrated optoelectronics

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The application of co-integration theory in ensemble pulsar timescale algorithm

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Research in Astronomy and Astrophysics 2019年第7期19卷 115-122页

作者： Feng Gao Ming-lei tong Yu-Ping Gao Ting-Gao Yang Cheng-Shi Zhao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 710600China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Physics Xi'an University of Science and TechnologyXi'an 710054China

Employing multiple pulsars and using an appropriate algorithm to establish ensemble pulsar timescale can reduce the influences of various noises on the long-term stability of pulsar timescale,compared to a single ***,due to the low timing precision and significant red noises of some pulsars,their participation in the construction of ensemble pulsar timescale is often *** by the principle of solving non-stationary sequence modeling using co-integration theory,we put forward an algorithm based on co-integration theory to establish an ensemble pulsar *** is found that this algorithm can effectively suppress some noise sources if a co-integration relationship between different pulsar data *** from the classical weighted average algorithm,the co-integration method provides the chance for a pulsar with significant red noises to be included in the establishment of an ensemble pulsar *** on data from the North American Nanohertz Observatory for Gravitational Waves(NANOGrav),we found that the co-integration algorithm can successfully reduce several timing noises and improve the long-term stability of the ensemble pulsar timescale.

关键词： pulsars general-time-methods analytical

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基于Wi-Fi+蜂窝的双通道切片加速系统设计与应用

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邮电设计技术 2024年第3期 88-92页

作者：岳红强张伟强童磊李莹雪中国联通智网创新中心北京100048

随着互联网业务的快速发展,人们对加速业务的需求越来越强烈,特别是视频直播、游戏和支付等业务,这些对网络带宽、时延、稳定性提出了更高的要求。为了满足这些需求,把以mpquic双通道加速技术和以移网QoS、宽带加速、城域网/骨干网QoS... 详细信息

随着互联网业务的快速发展,人们对加速业务的需求越来越强烈,特别是视频直播、游戏和支付等业务,这些对网络带宽、时延、稳定性提出了更高的要求。为了满足这些需求,把以mpquic双通道加速技术和以移网QoS、宽带加速、城域网/骨干网QoS为主要内容的运营商网络加速技术相结合,实现了一种新型的双通道加速系统。该系统已在视频直播和游戏加速业务中得到应用,并取得了良好的效果。

关键词：双通道加速网关 mpquic双通道移网QoS 宽带加速城域网/骨干网QoS

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骨性Ⅲ类患者正畸-正颌治疗后牙槽骨结构改建的锥形束CT测量

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中国组织工程研究 2024年第23期28卷 3729-3735页

作者：赵启航芦昕童磊商永慧李帅刘文周建华袁荣涛郭庆圆康复大学青岛医院/青岛市市立医院山东省青岛市266000 大连医科大学辽宁省大连市116000

背景:正畸-正颌联合治疗骨性Ⅲ类错颌的大多数研究主要关注患者侧貌的改善和后期的恢复情况,而观察患者下前牙牙槽骨改建这一类微观的研究较少。目的:应用口腔X射线侧位片和口腔锥形束CT评价骨性Ⅲ类错颌畸形患者正畸-正颌联合治疗前后... 详细信息

背景:正畸-正颌联合治疗骨性Ⅲ类错颌的大多数研究主要关注患者侧貌的改善和后期的恢复情况,而观察患者下前牙牙槽骨改建这一类微观的研究较少。目的:应用口腔X射线侧位片和口腔锥形束CT评价骨性Ⅲ类错颌畸形患者正畸-正颌联合治疗前后的下前牙去代偿疗效及牙槽骨结构改建情况。方法:选择2015年1月至2023年5月在康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸-正颌联合治疗的骨性Ⅲ类错颌畸形患者15例,治疗前后拍摄头颅X射线侧位片测量下前牙在牙槽骨中的角度及线距等指标,锥形束CT测量和分析下前牙唇/舌侧骨开裂长度(d-La/d-Li)以及骨开裂/骨开窗发生情况。结果与结论:①从X射线侧位片来看,与治疗前相比,下前牙去代偿后相应牙槽骨改建量变化明显,牙根明显向牙槽骨中心移动,但较正常个体仍有部分差距;②锥形束CT测量发现几乎所有牙齿治疗后牙槽骨骨开裂/骨开窗的长度和宽度都得到很大的改善,有的牙槽骨改建甚至已经达到了健康人水平;③治疗前大部分患者往往因为牙齿代偿生长而造成下切牙唇/舌侧的骨开窗/骨开裂,而在术前正畸阶段通过去代偿使牙槽骨改建,牙齿角度发生明显变化,术前正畸使上前牙内收,下前牙唇倾控根,但是术前去代偿量往往不足;在正颌手术阶段,颌骨位置通过定位导板切除,上颌骨前移,下颌骨后退;术后正畸过程中精调效果更好,虽然牙齿与颌骨位置均有一定程度的复发趋势,但术后正畸更接近正常值。

关键词：反颌正畸-正颌联合治疗下前牙去代偿骨开裂骨开窗

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A Stoneley wave method to detect interlaminar damage of metal layer composite pipe

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Frontiers of Mechanical Engineering 2015年第1期10卷 89-94页

作者： Bing LI lei QIANG tong LU Xu GENG Minghang LI State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an 710049 China

The interlaminar defect is a major form of damage in metal layer composite pipes which are widely used in petroleum and chemical industry. In this paper, a Stoneley wave method is presented to detect interlaminar damage in laminated pipe structure. Stoneley wave possesses some good characteristics, such as high energy and large displacement at the interface and non-dispersive in the high-frequency, so the sensitivity of detecting interlaminar damage can be improved and the higher frequency can be used in damage detection compared with Lamb waves. Additionally, as the frequency increases, the wavelength of the Stoneley wave reduces. Thus, its ability to detect small defects at the interface is enhanced. Finite element model of metal layer composite pipe with interlaminar damage is used to simulate wave propagation of Lamb waves and Stoneley wave, respectively. The damage location is calculated by using the Stoneley wave signal obtained from finite element model, and then the results are compared with the actual damage locations. The simulation examples demonstrate that the Stoneley wave method can better identify the interlaminar damage in laminated pipe structure compared with Lamb waves.

关键词： Stoneley wave interlaminar damage metallaminated pipe

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Soil warming effect on net ecosystem exchange of carbon dioxide during the transition from winter carbon source to spring carbon sink in a temperate urban lawn

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Journal of Environmental Sciences 2012年第12期24卷 2104-2112页

作者： Xiaoping Zhou Xiaoke Wang lei tong Hongxing Zhang Fei Lu Feixiang Zheng Peiqiang Hou WenzhiSong Zhiyun Ouyang Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeifing 100085China Graduate School of Chinese Academy of Sciences Beijing 100039China

The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in warmed environment. Soil warming effect on net ecosystem exchange （NEE） of carbon dioxide during the transition period from winter to spring was investigated in a temperate urban lawn in Beijing, China. The NEE （negative for uptake） under soil warming treatment （temperature was about 5~C higher than the ambient treatment as a control） was -0.71 ~mol/（***）, the ecosytem was a CO2 sink under soil warming treatment, the lawn ecosystem under the control was a CO2 source （0.13 Ixmol/（***））, indicating that the lawn ecosystem would provide a negative feedback to global warming. There was no significant effect of soil warming on nocturnal NEE （i.e., ecosystem respiration）, although the soil temperature sensitivity （Q10） of ecosystem respiration under soil warming treatment was 3.86, much lower than that in the control （7.03）. The CO2 uptake was significantly increased by soil warming treatment that was attributed to about 100% increase of ct （apparent quantum yield） and Amax （maximum rate of photosynthesis）. Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global warming than respiration in the transition period.

关键词： soil warming urban lawn C02 uptake ecosystem respiration

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Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： lei Wan Yizhou tong Xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

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IoV environment exploring coordination:A federated learning approach

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Digital Communications and Networks 2024年第1期10卷 135-141页

作者： tong Ding lei Liu Yi Zhu Lizhen Cui Zhongmin Yan School of Software Shandong UniversityJinan250101China

Exploring open fields with coordinated unmanned vehicles is popular in academia and *** of the most impressive applicable approaches is the Internet of Vehicles(lov).The IoV connects vehicles,road infrastructures and communication facilities to provide solutions for exploration ***,the coordination of acquiring information from multi-vehicles may risk data *** this end,sharing high-quality experiences instead of raw data has become an urgent *** paper employs a Deep Reinforcement Learning(DRL)method to enable IoVs to generate training data with prioritized experience and states,which can support the IoV to explore the environment more ***,a Federated Learning(FL)experience sharing model is established to guarantee the vehicles'*** numerical results show that the proposed method presents a better successful sharing rate and a more stable convergence within the comparison of fundamental *** experiments also suggest that the proposed method could support agents without full information to achieve the tasks.

关键词： Internet of vehicle Deep reinforcement learning Federated learning Data privacy

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Pulsar timing residuals due to individual non-evolving gravitational wave sources

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Research in Astronomy and Astrophysics 2014年第4期14卷 390-400页

作者： Ming-lei tong Cheng-Shi Zhao Bao-Rong Yan Ting-Gao Yang Yu-Ping Gao National Time Service Center Chinese Academy of Sciences Key Laboratory of Time and Frequency Primary Standards Chinese Academy of Sciences Key Laboratory of Precision Navigation and Timing Technology Chinese Academy of Sciences

The pulsar timing residuals induced by gravitational waves from non- evolving single binary sources are affected by many parameters related to the relative positions of the pulsar and the gravitational wave sources. We will analyze the various effects due to different parameters. The standard deviations of the timing residuals will be calculated with a variable parameter fixing a set of other parameters. The or- bits of the binary sources will be generally assumed to be elliptical. The influences of different eccentricities on the pulsar timing residuals will also be studied in detail. We find that the effects of the related parameters are quite different, and some of them display certain regularities.

关键词： gravitational waves: general -- pulsars: general -- binaries: general

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