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Types of Maize Virus Diseases and Progress in Virus Identification Techniques in China

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Journal of Northeast Agricultural University(English Edition) 2014年第1期21卷 75-83页

作者： Cui Yu Zhang Ai-hong ren Ai-jun Miao hong-qin College of Humanities & Social Science University of Science and Technology of China Institute of Plant Protection Hebei Academy of Agriculture and Forest Sciences/IPM Center of Hebei Province/Key Laboratory of IPM on Crops in Northern Region of North China Ministry of Agriculture

There are a total of more than 40 reported maize viral diseases worldwide. Five of them have reportedly occurred in China. They are maize rough dwarf disease, maize dwarf mosaic disease, maize streak dwarf disease, maize crimson leaf disease, maize wallaby ear disease and corn lethal necrosis disease. This paper reviewed their occurrence and distribution as well as virus identification techniques in order to provide a basis for virus identification and diagnosis in corn production.

关键词： maize virus disease virus species identification technique

基于慢波半模基片集成波导的等长等宽小型化移相器

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电子学报 2023年第10期51卷 2747-2753页

作者：黄文陈肖任仪重庆邮电大学光电工程学院重庆400065

针对基片集成波导移相器小型化、高性能的需求,本文提出了基于慢波半模基片集成波导(Slow-Wave Half-Mode Substrate Integrated Waveguide,SW-HMSIW)的等长等宽小型化移相器.该SW-HMSIW上层金属表面由微带折线单元周期性加载构成,提高... 详细信息

针对基片集成波导移相器小型化、高性能的需求,本文提出了基于慢波半模基片集成波导(Slow-Wave Half-Mode Substrate Integrated Waveguide,SW-HMSIW)的等长等宽小型化移相器.该SW-HMSIW上层金属表面由微带折线单元周期性加载构成,提高了SW-HMSIW的等效介电常数和磁导率,从而降低了SW-HMSIW的截止频率和相速度,实现了慢波效应并获得尺寸的减小.此外,可以通过调节微带折线单元横向和纵向的尺寸,灵活调节SW-HMSIW的相速度和截止频率.基于这一原则,本文设计实现了SW-HMSIW等长等宽小型化移相器,同时它具有较宽的工作带宽.测试结果表明,所设计的移相器在8.7~14.2 GHz内实现了90°±4°的相移量,相对带宽为48%,回波损耗优于12 dB,具有良好的传输性能和移相效果,并且具有小型化和等长等宽结构特点,适用于在大规模阵列天线的应用.

关键词：移相器基片集成波导小型化慢波结构

A small D-A molecule with highly heat-resisting room temperature phosphorescence for white emission and anti-counterfeiting

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Chinese Journal of Structural Chemistry 2024年第3期43卷 3-9页

作者： Kun Zhang Ni Dan Dan-Dan ren Ruo-Yu Zhang xiaoyan Lu Ya-Pan Wu Li-Lei Zhang hong-Ru Fu Dong-Sheng Li College of Materials and Chemical Engineering China Three Gorges UniversityYichang443002PR China College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang471934PR China

Achieving high heat-resisting room temperature phosphorescence(RTP)performance and robust white emission from pure small molecules is a meaningful but challenging ***,a simple donor-acceptor(D-A)molecule,9-(1H-benzotriazol-1-ylmethyl)-9H-carbazole(CzBtrz),was *** simple molecule not only exhibits multiple emissions including white light,thermally activated delayed fluorescence(TADF)and ultralong RTP with a lifetime of 988.54 ms at 545 nm,but also shows superhigh heat-resisting phosphorescence property which can maintain stability in a large temperature region from 77 to 350 K(ΔT=273 K),exceeding those of other RTP ***,this molecule shows the time-evolved dynamic *** experimental and theoretical an-alyses from CzBtrz crystal demonstrate that the intramolecular charge transfer(ICT)interaction and molecular stacking play an important role in the generation of ***,this work provides an efficient strategy to design ultrahigh heat-resistant RTP,ultralong RTP and single-phased white-light emitting materials.

关键词： Ultralong RTP TADF D-A molecule Heat-resisting White light

Psychological distress, family functioning, and social support in family caregivers for patients with dementia in the mainland of China

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Chinese Medical Journal 2013年第18期126卷 3417-3421页

作者： ZHANG hong XIONG Rong-hong Sara Hujiken ZHANG Jun-jian ZHANG xiao-qin Department of Neurology Zhongnan Hospital of Wuhan University Wuhan Hubei 430071 China Teaching and Research Section of Neuropsychiatry Zhongnan Hospital of Wuhan University Wuhan Hubei 430071 China Department of Neurology Xinjiang Uygur Autonomous Region Hospital of Traditional Chinese Medicine Urumqi Xinjiang 830000 China

Background Dementia is a chronic progressive disease seriously affecting the patient＇s daily life and working skills and may cause the patient disability and dependence. Thus, caring for dementia patients inevitably falls on families in the mainland of China. Unfortunately, there are rarely enough reports available about mental health and social support in family caregivers for domestic dementia patients. This study aimed to investigate the changes in psychological status and social support in domestic dementia family caregivers and hope the government and relevant departments pay more attention to the family caregiver＇s psychological change, which may be better for dementia patients. Methods Fifty-eight immediate family caregivers （family group） for dementia patients, including 21 Alzheimer＇s disease （AD） and 37 vascular dementia inpatients, were recruited for interview. Fifty-eight age- and sex-matched normal volunteers （control group） were also interviewed in the same period. The psychiatric distress was assessed by the Symptom Checklist 90 （SCL-90）, family functioning was assessed by the Family Assessment Device （FAD）, and the social support was assessed by the Multidimensional Scale of Perceived Social Support （MSPSS）. Group differences were analyzed using unpaired t test for comparison of SCL-90, FAD, and MSPSS mean scores. Pearson＇s correlation coefficient was used to find the association between the various dimensions of FAD and the social support from dementia family caregivers. Results Except phobic anxiety dimension, the other dimensions of SCL-90 mean scores were significantly higher in the family group than those in the control group （P 〈0.05）. In the family group, except affective involvement dimension, the other dimensions of FAD mean scores were within the scope of unhealthy family functioning. Significant differences in problem solving, communication, roles, affective responsiveness, behavioral control, general functioning, and the total MSPSS mean

关键词： dementia family caregivers psychiatric distress familyfunctioning social support

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基于混合反馈机制的扩展蚁群算法

控制与决策 2022年第12期37卷 3160-3170页

作者：冯振辉肖人彬华中科技大学人工智能与自动化学院武汉430074 华中科技大学人工智能研究院武汉430074

由于传统蚁群算法基于正反馈机制的单一搜索方式,导致其存在收敛速度慢、易陷入局部极值的缺点.针对该问题提出一种基于混合反馈机制的扩展蚁群算法(MF-ACO),该算法在传统蚁群算法的基础上定义一种具有较强全局搜索能力的扩展型蚂蚁,帮... 详细信息

由于传统蚁群算法基于正反馈机制的单一搜索方式,导致其存在收敛速度慢、易陷入局部极值的缺点.针对该问题提出一种基于混合反馈机制的扩展蚁群算法(MF-ACO),该算法在传统蚁群算法的基础上定义一种具有较强全局搜索能力的扩展型蚂蚁,帮助算法跳出局部极值;参考蚁群劳动分工行为,设计基于刺激-响应分工模型的负反馈平衡机制,动态平衡算法的收敛能力和全局搜索能力;最后依据分工模型对蚂蚁个体的信息素更新策略进行改进,进一步加快算法收敛速度.以多个TSP实例作为测试对象进行仿真实验,实验结果验证了所提算法的优越性,并将该算法用于机器人路径规划问题,在实际应用中进一步验证了所提算法的有效性.

关键词：正反馈混合反馈机制局部极值劳动分工刺激-响应分工模型

Effect of Surface Treatment on Bonding Strength of Aluminum-Magnesium Hot-Rolled Composite Plate

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稀有金属材料与工程 2024年第8期53卷 2167-2173页

作者： Yang Bin Bai Wenbo Zheng Yang Yu Chao xiao hong National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China

The effect of different surface treatments on the bonding strength of composite plates was investigated under the conditions of 400℃ and reduction ratio of 45%.Results show that the wire brush grinding treatment can only eliminate the oxide film on the plate surface,but it can hardly produce a hard layer on the plate *** bonding effect depends on the element diffusion promoted by the close contact between the metals on both sides of the *** anodic oxidation,there is a hard layer on the metal surface,and the hard layer broken during the rolling process forms a mechanical occlusion at the bonding ***,the hard layer cannot form an effective combination with the metal at the interface,and the bonding can only occur in the fresh metal bonding area at the crack of the hard *** acid-alkali washing treatment can completely remove the hard layer on the surface of both alloys without increasing the surface roughness of the plate,and the metal on both sides of the interface is more closely bonded during the rolling *** optimal bonding strength can be obtained by surface treatment of acid-alkali washing for the aluminum-magnesium hot-rolled bonding.

关键词： aluminum-magnesium composite plate surface treatment hard layer bonding strength

What is the destiny of a threatened fish, Ptychobarbus chungtienensis, now that non-native weatherfishes have been introduced into Bita Lake, Shangri-La？

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Zoological Research 2016年第5期37卷 275-280页

作者： Wan-Sheng JIANG Tao QIN Wei-Ying WANG Ya-Peng ZHAO Shu-Sen SHU Wei-hong SONG xiao-Yong CHEN Jun-Xing YANG State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Yezin Nay Pyi Taw 05282 Myanmar POWERCHINA Kunming Engineering Corporation Limited Kunming Yunnan 650051 China Management Division of Yunnan Bitahai Nature Reserve Shangri-La Yunnan 674400 China

Biological invasion is a pervasive negative force of global change, especially in its effects on sensitive freshwater ecosystems. Even protected areas are usually not immune. Ptychobarbus chungtienensis is a threatened freshwater fish now almost confined to Bita Lake, in the Shangri-La region of Yunnan province, China. Its existence is threatened by the introduction of non-native weatherfishes （Misgumus anguillicaudatus and Paramisgurnus dabryanus） by an unusual method known as ＇prayer animal release＇ Periodic surveys revealed the ratio of invasive weatherfishes to P. chungtienensis has been increasing since the former species was first recorded from the lake in August, 2009. Ptychobarbus chungtienensis shows low genetic diversity in the relict Lake Bita population. Weatherfishes, however, have highly successful survival strategies. The degree of dietary overlap between the species is alarming and perhaps critical if food is found to be a limiting factor.

关键词： Biological invasion Threatened fish Prayer animal release Genetic diversity Dietary

Tunable Vertical-Cavity Surface-Emitting Lasers Integrated with Two Wafers

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Chinese Physics Letters 2011年第2期28卷 129-131页

作者： ren Xiu-Juan GUAN Bao-Lu GUO Shuai LI Shuo LI Chuan-Chuan HAO Cong-Xia ZHOU hong-Yi GUO Xia Key Laboratory of Opto-electronics Technology(Ministry of Education) Beijing University of TechnologyBeijing 100124

A novel two-wafer concept for micro-electro-mechanically tunable vertical cavity surface emitting lasers(VCSELs)is *** VCSEL is composed by two wafers:one micro-electromechanical-system membrane wafer with four arms to adjust the cavity length through electrostatic actuation and a"half-VCSEL"wafer consisting of a fixed bottom mirror and an amplifying active *** measurement results of the electricity pumped tunable VCSEL with more than 9mW output power at room temperature over the tuning range prove the feasibility of the proposition.

关键词： tunable tuning pumped

Polymerizable AEE-active Dye with Optical Activity for Fluorescent Nanoparticles Based on Phenothiazine:Synthesis,Self-assembly and Biological Imaging

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Chinese Journal of Polymer Science 2021年第11期39卷 1431-1440页

作者： Zeng-Fang Huang Ya-Li Chen Chao-Yue Zhou Yan-hong Li Mei Li xiao-Bo Liu Liu-Cheng Mao Jin-Ying Yuan Lei Tao Yen Wei School of Materials&Food Engineering Zhongshan InstituteUniversity of Electronic Science&Technology of ChinaZhongshan 528402China School of Materials and Energy University of Electronic Science&Technology of ChinaChengdu 610054China Department of Chemistry the Tsinghua Center for Frontier Polymer ResearchTsinghua UniversityBeijing 100084China

In consideration of various advantages such as less harm,higher sensitivity,and deeper imaging depth,etc.,AIE materials with longwave emission are attracting extensive attention in the fields of vascular visualization,organelle imaging,cells tracker,forensic detection,bioprobe and chemosensor,*** this work,a novel fluorescent(R)-PVHMA monomer with chirality and aggregation-induced emission enhancement(AEE)characteristics was acquired through enzymatic transesterification reaction basing on phenothiazine,and its[α]D25℃value was about-6.39°with a 3.08 eV bandgap calculated by the quantum ***,a series of PEG-PVH1 and PEG-PVH2 copolymers with chirality feature were achieved through RAFT polymerization of the obtained(R)-PVHMA and PEGMA with various feed *** the feed molar ratio of(R)-PVHMA increased from 21.5%to 29.6%,its actual molar fractions in the PEG-PVH1 and PEG-PVH2 copolymers accordingly increased from 18.1%to 25.7%.The molecular weight of PEG-PVH1 was about 2.2×10^(4) with a narrow PDI,and their kinetics estimation showed a first-order quasilinear *** aqueous solution,the amphiphilic copolymers PEG-PVH could self-assemble into about 100 nm *** a 90%water solution of H_(2)O and THF mixture,the fluorescence intensity had the maximum value,and the emission wavelength presented at 580 and 630 *** investigation of cytotoxicity and cells uptake showed that PEG-PVH FONs performed outstanding biocompatibility and excellent cells absorption effects,which have great potential in bioimaging application.

关键词： AEE dye Optical activity RAFT polymerization Long-wave emission Biological imaging