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Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

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Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong yan Xiliang li Ke jin Institute of Grassland Research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P lies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

Numerical Study of Plasmonic Modes in Hexagonally Arranged Metal Nanowire Array

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Chinese Physics Letters 2012年第7期29卷 106-109页

作者： yan Hao-Zhe PENG jing-Gang li jin-yan yanG Lu-Yun Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074

A plasmonic waveguide containing hexagonally arranged parallel metallic nanowires with hexagonal cross sections embedded in a silica fiber is proposed and *** to simulations of surface plusmon polariton eigenmodes at varying geometrical transverse parameters,we obtain comprehensive mode characteristics,including field mode distribution,effective refractive index,propagation length,and lateral mode radius,thus allowing us to investigate the precise trade-off between propagation length and confinement,which is very important in designing plasmonic waveguides of different *** waveguide is also proved to be robust against fabrication imperfections,which makes its manufacture and practical applicability feasible.

关键词： hexagonal mode waveguide

Simulation of Voltage SET Operation in Phase-Change Random Access Memories with Heater Addition and Ring-Type Contactor for Low-Power Consumption by Finite Element Modeling

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Chinese Physics Letters 2010年第6期27卷 250-253页

作者： GONG Yue-Feng SONG Zhi-Tang liNG Yun liU yan li Yi-jin State Key Laboratory of Functional Materials for Informatics Laboratory of Nanotechnology Shanghai Institute of Micro-system and Information Technology Chinese Academy of Sciences Shanghai 200050

A three-dimensional finite element model for phase change random access memory is established to simulate electric, thermal and phase state distribution during （SET） operation. The model is applied to simulate the SET behaviors of the heater addition structure （HS） and the ring-type contact in the bottom electrode （RIB） structure. The simulation results indicate that the small bottom electrode contactor （BEC） is beneficial for heat efficiency and reliability in the HS cell, and the bottom electrode contactor with size Fx=80 nm is a good choice for the RIB cell. Also shown is that the appropriate SET pulse time is lOOns for the low power consumption and fast operation.

关键词： SIMULATION methods & models PHASE transformations (Physics) RANDOM access memory ELECTRODES REliABIliTY (Engineering) ENERGY consumption

Photovoltaic properties of MEH-PPV/TiO_2 nanocomposites

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Chinese Science Bulletin 2008年第18期53卷 2743-2747页

作者： li yan HOU yanBing jin Hui SHI QuanMin WANG yan FENG ZhiHui Key Laboratory of Luminescence and Optical Information Ministry of Education of China Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China

Photovoltaic properties of photodiodes based on nano-TiO_2 and poly[2-methoxy,5-(2′-ethlhexyloxy)- p-phenylenevinylene] (MEH-PPV) composites are investigated. By comparing composite devices with the same weight of TiO_2 (nanoparticles and nanotubes):MEH-PPV, it was found that the device with TiO_2 nanotubes exhibited better performance. By further optimizing the weight radio of TiO_2 nano- tubes:MEH-PPV, we gained the device with a short circuit current density of 9.27 μA/cm2 with a light intensity of 16.7 mW/cm2 at the 500 nm wavelength, the highest open-circuit voltage of 1.1 V, and a photosensitivity of 332 at reverse bias of -0.6 V. The photosensitivity is improved by a factor of 33 compared with the undoped MEH-PPV device.

关键词：太阳能电池氧化硅纳米管 MEH-PPV 纳米复合材料

Controlling the Spectral Characteristics of Bismuth Doped Silicate Glass Based on the Reducing Reaction of Al Powder

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Chinese Physics Letters 2013年第4期30卷 95-98页

作者： WANG yan-Shan JIANG Zuo-Wen PENG jing-Gang li Hai-Qing yanG Lu-Yun li jin-yan DAI Neng-li Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074

Silicate glasses co-doped with Al metal powder and Bi2O3 are *** effects of Al on spectral properties of samples are *** is found that the absorption intensity increases with increasing Al concentration in bismuth doped silicate *** near-infrared(NIR)emission of the samples can be controlled by Al powder concentration no matter whether or not excited by 808 nm or 976 nm ***,the influence of Al on formation of Bi-NIR active ions is *** dependence relationship between the emission property of~416 nm and Al concentration is a way to investigate the NIR emission origin of bismuth doped glass.

关键词： glasses bismuth Glass

Model architecture level privacy leakage in neural networks

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Science China(Information Sciences) 2024年第3期67卷 20-32页

作者： yan li Hongyang yan Teng HUANG Zijie PAN Jiewei LAI Xiaoxue ZHANG Kongyang CHEN jin li Institute of Artificial Intelligent and Blockchain Guangzhou University Pazhou Lab

Privacy leakage is one of the most critical issues in machine learning and has attracted growing interest for tasks such as demonstrating potential threats in model attacks and creating model *** recent years, numerous studies have revealed various privacy leakage risks(e.g., data reconstruction attack, membership inference attack, backdoor attack, and adversarial attack) and several targeted defense approaches(e.g., data denoising, differential privacy, and data encryption). However, existing solutions generally focus on model parameter levels to disclose(or repair) privacy threats during the model training and/or model interference process, which are rarely applied at the model architecture level. Thus, in this paper, we aim to exploit the potential privacy leakage at the model architecture level through a pioneer study on neural architecture search(NAS) paradigms which serves as a powerful tool to automate a neural network *** investigating the NAS procedure, we discover two attack threats in the model architecture level called the architectural dataset reconstruction attack and the architectural membership inference attack. Our theoretical analysis and experimental evaluation reveal that an attacker may leverage the output architecture of an ongoing NAS paradigm to reconstruct its original training set, or accurately infer the memberships of its training set simply from the model architecture. In this work, we also propose several defense approaches related to these model architecture attacks. We hope our work can highlight the need for greater attention to privacy protection in model architecture levels(e.g., NAS paradigms).

关键词： neural architecture search data reconstruction attack membership inference attack

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双官能化溶聚丁苯橡胶在轮胎胎面胶中的应用

合成橡胶工业 2024年第3期47卷 247-251页

作者：默云娟薛健李锦彦张玺于杰中国石油独山子石化公司研究院新疆克拉玛依833699 中国石油独山子石化公司生产运行处新疆克拉玛依833699 新疆橡塑材料实验室新疆克拉玛依833699

使用国产双端官能化产品SSBR2060-N和日本Zeon公司单端官能化产品Nipol■NS616进行成品轮胎试制及性能评价。结果表明,使用SSBR2060-N制备的成品轮胎外边缘尺寸达到技术标准,抗湿滑性能和滚动阻力均达到了欧洲议会和欧盟理事会联合颁布... 详细信息

使用国产双端官能化产品SSBR2060-N和日本Zeon公司单端官能化产品Nipol■NS616进行成品轮胎试制及性能评价。结果表明,使用SSBR2060-N制备的成品轮胎外边缘尺寸达到技术标准,抗湿滑性能和滚动阻力均达到了欧洲议会和欧盟理事会联合颁布的轮胎标签法规EU2020/740规定的双B轮胎级别,强度性能、高速性能和耐久性能等均与使用Nipol■NS616制备的成品轮胎相当且均能够满足国家标准要求。

关键词：双端官能化溶聚丁苯橡胶轮胎胎面胶双B级轮胎物理机械性能动态力学性能成品轮胎性能

Blue-Extended Supercontinuum Generation in Photonic Crystal Fibers with Picosecond Pulse Pumping

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Chinese Physics Letters 2012年第12期29卷 109-111页

作者： ZHU Xian ZHANG Xin-Ben CHEN Xiang PENG jing-Gang DAI Neng-li li jin-yan Wuhan National Laboratory of Optoelectronics Huazhong University of Science and TecnologyWuhan 430074

We report supercontinuum generation extending to the blue spectral region using pulses of 1.8 ps duration at 1040 nm in GeO_(2)-doped core photonic crystal fibers.A spectrum in fundamental mode spanning from 415 nm to beyond 1750 nm is generated in a uniform photonic crystal fiber(PCF).A zero dispersion wavelength decreasing PCF is fabricated to optimize the parameters for deeper blue components generated by cross-phase modulation and group-velocity *** the PCF is pumped at a low input power of 1.3 W in anomalous dispersion and relatively far from the zero dispersion wavelength,a flat continuum covering 406.1-671.8 nm is generated,which is of primary importance in a number of bio-photonic applications such as fluorescence imaging microscopy.

关键词： pumped Crystal fiber

PMD compensation using birefringence photonic crystal fiber in 40Gbit/s optical communication system

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Optoelectronics Letters 2008年第1期4卷 30-32页

作者： CHEN Ming yanG Si-gang li jin-yan CHEN Wei XIE Shi-zhong Department of Electronic Engineering of Tsinghua University Beijing 100084 China Fiber Home Telecommunication Technologies CO. LTD Wuhan Research Institute of Post and TelecommunicationsWuhan 430074 China

A birefringence photonic crystal fiber is used for PMD compensation in a single-channel 40Gbit/s-speed optical communi- cation system with CSRZ format. The experimental results of transmission show that the PMD compen... 详细信息

关键词：光通信系统双折射光子晶体光纤光纤通信偏振模式散射