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A mechanically coupled MEMS filter with high-Q width extensional mode resonators

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Journal of Semiconductors 2024年第8期45卷 41-48页

作者： Wei Wang Wenli liu Junyuan zhao Bo Niu Zeyu Wu Yinfang Zhu {2. Yang Fuhua Yang institute of Semiconductors Chinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This work presents a novel radio frequency(RF)narrowband Si micro-electro-mechanical systems(MEMS)filter based on capacitively transduced slotted width extensional mode(WEM)*** flexibility of the plate leads to multiple modes near the target *** high Q-factor resonators of around 100000 enable narrow bandwidth filters with small size and simplified *** 1-wavelength and 2.wavelength WEMs were first developed as a pair of coupled modes to form a *** reduce bandwidth,two plates are coupled with aλ-length coupling *** 79.69 MHz coupled plate filter(CPF)achieved a narrow bandwidth of 8.8 kHz,corresponding to a tiny 0.011%.The CPF exhibits an impressive 34.84 dB stopband rejection and 7.82.dB insertion loss with near-zero passband *** summary,the RF MEMS filter presented in this work shows promising potential for application in RF transceiver front-ends.

关键词： MEMS narrowband filter mechanically coupling quality factor width extensional mode

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science china(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, liu Changming1, , WU Xianfeng2.2.& zhao Weimin{2. Key Laboratory of Water Cycle & Related Land Surface Processes, {2. of geographic Science and natural resources research, chinese academy of sciences, Beijing 100101, china 2. {2. of Environmental Science, Beijing Normal University, Beijing 100875, china 3. Water resources Conservation Committee of Yellow River, Zhengzhou 450003, china chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Phenology of different types of vegetation and their response to climate change in the Qilian Mountains,china

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Journal of Mountain Science 2024年第2期21卷 511-525页

作者： zhao Kaixin LI Xuemei ZHANG Zhengrong liu Xinyu Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering research Center of Technologies and Applications for National geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National geographic State Monitoring Lanzhou 730070China

The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate *** relationship between changes in vegetation growth and climate remains *** this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2.02.to ***,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation ***,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly *** SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other *** EOS in MDW and GSD were concentrated between late August and April and early September and early January,*** phenology exhibits distinct responses to seasonal temperature and precipitation *** advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 2..17%of the study area,*** advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 2..17%of the area,*** the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect *** indirec

关键词： Vegetation phenology Time series decomposition Path Analysis Climate change

Method for Evaluating the Degrees of Land Use Sustainability of Mountainous County and its Application in Yunnan Province,china

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Journal of Mountain Science 2008年第2期5卷 98-112页

作者： YANG Zisheng liu Yansui TAO Wenxing XU Jingling zhao Qiaogui institute of Land ＆ resources and Sustainable Development Yunnan University of Finance and Economics Kunming 650221 China Institu te of geographic sciences and {2. resources research Chinese Academy of Science Beijing 100101 China Department of Land ＆ resources of Yunnan Province Kunming 650224 China

The evaluation of sustainable land use is the key issue in the field of studying the sustainable land utilization. In general analysis, the sustainable land use is evaluated respectively from its ecological sustainability, economic sustainability and social sustainability in china and other countries in recent years. Although this evaluation is an important work, it seems insufficient and hard to comprehensively reflect the whole degree of land use sustainability. Thus, to make up this deficiency, this paper brings forward the evaluation indexes, which make it possible to quantitatively reflect the whole degree of land use sustainability, namely, the concept of ＂degrees of overall land use sustainability＂（Dos）, and research and measurement development of the method of and calculation in Dos. Taking the evaluation of the degree of land use sustainability in county regions of Yunnan Province as the actual example for analysis, results are basically as follows： 1） The degree of land use sustainability （Dos） is the ration index to organically and systematically integrate the degree of ecological friendliness （DeF）, the degree of economic viability （Dev） and the degree of social acceptability （Dsa）, able to comprehensively reflect the whole sustainability degree of regional land use 2. Based on the value of Dos, the grading system and standard for the sustainability of land use may be established and totally divided into five grades, namely, the high-degree sustainability, middle-degree sustainability, low-degree sustainability, conditional sustainability and non-sustainability. Meanwhile, the standard for distinguishing sustainability grades has also been confirmed so as to determine the nature of sustainability degrees in different grades. This makes the possibility for the combination of nature determination with ration in research result and provides with the scientific guideline and decision-making gist for better implementation of sustainable land use strategy

关键词： Land use degrees of overall sustainability evaluation method county level degrees of ecological friendliness degrees of economic viability degrees of social acceptability

Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in china

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Journal of geographical sciences 2002年第4期12卷 397-404页

作者： DENG Xiangzheng, liu Jiyuan, ZHUANG Dafang, ZHAN Jinyan, zhao Tao(Inst. of {2. {2. and natural resources research, CAS, Beijing 100101, china) Inst. of geographic sciences and {2. resources research CAS 北京 100101

This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern china. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.

关键词： land use driving force interlock area of farming and pasturing china

A New Analytical Method of the Water resources Allocation in china

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A New Analytical Method of the Water Resources Allocation in...

Origin and evolution of a new tetraploid mangrove species in an intertidal zone

2.14年环境污染与大众健康学术会议

作者： Yanqi zhao1 2.3 Changming liu1 Ying YANG2.Hongxing ZHENG1 1{2. of {2. sciences and natural resources research CAS Beijing 100101 china 2.2. of resources & Environment Henan Polytechnic University(HPU) Jiaozuo Henan 45400 china 3Graduate University of{12. Beijing 100101 china

The paper introduces the Gini coefficient of economics as a new method of analyzing the inter-provincial allocation of water resources in *** calculated the Gini coefficient for selected indices based upon the statistical data for each province from 1997 to 2.08,respectively taking the population,GDP and the cultivated area as the basic matching ***,we proposed two novel indexes:the Dependence Coefficient to weigh the degree of reliance on the surface water or groundwater for the separated regions and the Burden Coefficient of water use to judge the efficiency and the level of fairness of water consumption by different *** results show that the allocation of water resources calculated per capita,per unit GDP and per unit area of arable land is very *** particular,some provinces located north of the Yangtze River lack water resources and strongly depend on the *** water efficiency is there lower than in other parts of ***,in order to alleviate the water stress in the northern provinces of the country,an improvement of the technological level of water resources exploitation and utilization and also the restructuring of the economic activity are necessary.

关键词： water resources allocation Gini coefficient Dependence Coefficient Burden Coefficient

来源： cnki会议评论

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Plant Diversity 2024年第4期46卷 476-490页

作者： Hui Feng Achyut Kumar Banerjee Wuxia Guo Yang Yuan Fuyuan Duan Wei Lun Ng Xuming zhao Yuting liu Chunmei Li Ying liu Linfeng Li Yelin Huang State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant resources School of Life SciencesSun Yat-sen UniversityGuangzhou 510275GuangdongChina Department of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhai 519041GuangdongChina china-ASEAN College of Marine sciences Xiamen University MalaysiaSepang 43900SelangorMalaysia School of Agriculture Sun Yat-sen UniversityShenzhen 518107GuangdongChina School of Ecology Sun Yat-sen UniversityShenzhen 518107GuangdongChina

Polyploidy is a major factor in the evolution of plants,yet we know little about the origin and evolution of polyploidy in intertidal *** study aimed to identify the evolutionary transitions in three truemangrove species of the genus Acanthus distributed in the Indo-West Pacific *** this purpose,we took an integrative approach that combined data on morphology,cytology,climatic niche,phylogeny,and biogeography of 493 samples from 42.geographic *** results show that the Acanthus ilicifolius lineage distributed east of the Thai-Malay Peninsula possesses a tetraploid karyotype,which is morphologically distinct from that of the lineage on the west *** haplotype networks and phylogenetic trees for the chloroplast genome and eight nuclear genes reveal that the tetraploid species has two sub-genomes,one each from *** and ***,the paternal and maternal parents,*** structure analysis also supports the hybrid speciation history of the new tetraploid *** two sub-genomes of the tetraploid species diverged from their diploid progenitors during the *** niche models revealed that the tetraploid species not only occupied the near-entire niche space of the diploids,but also expanded into novel *** findings suggest that *** species distributed on the east side of the Thai-Malay Peninsula should be regarded as a new species,***,which originated from hybridization between *** and ***,followed by chromosome *** is the first report of a true-mangrove allopolyploid species that can reproduce sexually and clonally reproduction,which explains the long-term adaptive potential of the species.

关键词： Acanthus Allopolyploid Biogeography Evolution Hybridization Polyploidy

A CMIP6-based assessment of regional climate change in the chinese Tianshan Mountains

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Journal of Arid Land 2024年第2期16卷 195-219页

作者： liu Xinyu LI Xuemei ZHANG Zhengrong zhao Kaixin LI Lanhai Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering research Center of Technologies and Applications for National geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National geographic State Monitoring Lanzhou 730070China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

Climate warming profoundly affects hydrological changes,agricultural production,and human *** and semi-arid areas of china are currently displaying a marked trend of warming and *** chinese Tianshan Mountains(CTM)have a high climate sensitivity,rendering the region particularly vulnerable to the effects of climate *** this study,we used monthly average temperature and monthly precipitation data from the CN05.1 gridded dataset(1961-2.14)and 2. global climate models(GCMs)of the Coupled Model Intercomparison Project Phase 6(CMIP6)to assess the applicability of the CMIP6 GCMs in the CTM at the regional *** on this,we conducted a systematic review of the interannual trends,dry-wet transitions(based on the standardized precipitation index(SPI)),and spatial distribution patterns of climate change in the CTM during *** further projected future temperature and precipitation changes over three terms(near-term(2.2.-2.40),mid-term(2.41-2.60),and long-term(2.81-2.00))relative to the historical period(1961-2.14)under four shared socio-economic pathway(SSP)scenarios(i.e.,SSP1-2.6,SSP2.4.5,SSP3-7.0,and SSP5-8.5).It was found that the CTM had experienced significant warming and wetting from 1961 to 2.14,and will also experience warming in the future(2.2.-2.00).Substantial warming in 1997 was captured by both the CN05.1 derived from interpolating meteorological station data and the multi-model ensemble(MME)from the CMIP6 *** MME simulation results indicated an apparent wetting in 2.08,which occurred later than the wetting observed from the CN05.1 in *** GCMs generally underestimated spring temperature and overestimated both winter temperature and spring precipitation in the *** and wetting are more rapid in the northern part of the *** the end of the 2.st century,all the four SSP scenarios project warmer and wetter conditions in the CTM with multiple dry-wet ***,the rise in precipitation fails to counterbal

关键词： climate change Coupled Model Intercomparison Project Phase 6(CMIP6) global climate models(GCMs) shared socio-economic pathway(SSP)scenarios standardized precipitation index(SPI) chinese Tianshan Mountains

入侵软体动物感染广州管圆线虫的特性及检测研究进展

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生态科学 2024年第05期43卷 216-222页

作者：刘金苓陈慧莹刘仟惠潘广娜赵本良广东第二师范学院生物与食品工程学院华南农业大学资源环境学院

广州管圆线虫有复杂的生活史及繁多的宿主,具较强的感染性和致病性,存在严重健康威胁。外来软体动物的入侵已成为广州管圆线虫扩散的重要途径。对入侵软体动物感染广州管圆线虫的研究日渐增多,宿主体内线虫的检测技术也在逐步完善。然而... 详细信息

广州管圆线虫有复杂的生活史及繁多的宿主,具较强的感染性和致病性,存在严重健康威胁。外来软体动物的入侵已成为广州管圆线虫扩散的重要途径。对入侵软体动物感染广州管圆线虫的研究日渐增多,宿主体内线虫的检测技术也在逐步完善。然而,国内外学者对广州管圆线虫感染入侵软体动物的文献研究仍较分散,在入侵软体动物的易感特性和检测技术方面仍缺乏系统探讨。因此,文章综述了近2.年来广州管圆线虫感染全球入侵软体动物的研究,系统分析了广州管圆线虫感染入侵软体动物的种类、易感性、地理分布、基因特征、寄主响应和检测方法等方面的研究进展。目前报道的易感广州管圆线虫的全球入侵软体动物至少涉及15种。福寿螺、褐云玛瑙螺、中国圆田螺、河蚬可被L1—L3幼虫寄生,感染后氮代谢和氧化代谢增强。入侵软体动物对广州管圆线虫的易感性与宿主种类、发育期、孳生环境、感染剂量及感染时长有关。广州管圆线虫检测包括形态学和分子生物学方法,后者灵敏度和准确度更高。广州管圆线虫可“搭乘”入侵软体动物在全球扩散。同步阐明入侵软体动物的扩散规律和广州管圆线虫的寄生习性,可为广州管圆线虫的发生、防控及管理提供有益参考。

关键词：广州管圆线虫入侵软体动物地理分布易感性检测方法