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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae)

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Plant Diversity 2024年第4期46卷 448-461页

作者： hai-yao Chen Zhi-Rong zhang Xin yao Ji-Dong Ya Xiao-Hua jin Lin Wang Lu Lu De-Zhu Li Jun-Bo Yang Wen-Bin Yu Center for Integrative Conservation&Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of chinese academy of sciences Huairou DistrictBeijing 101408China Plant Germplasm and Genomics Center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China State Key Laboratory of Plant Diversity and Specility Crops Institute of BotanyChinese Academy of SciencesHaidian DistrictBeijing 100093China School of Pharmaceutical sciences Yunnan Key Laboratory of Pharmacology for Natural Productsand Yunnan College of Modern Biomedical IndustryKunming Medical UniversityKunmingYunnan 650500China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar

Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the ***,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this *** this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate *** dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle *** *** to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene *** analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon *** hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle *** transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification *** study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia.

关键词： Cymbidium East Asia Asian monsoons Climate change Biogeographical patterns

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Reducing two-way splitting error of FFD method in dual domains

Reducing two-way splitting error of FFD method in dual domai...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： jin-hai zhang and zhen-xing yao 1 chinese academy of sciences,Institute of geology and geophysics,{3.,china.

The Fourier finite-difference(FFD) method is very popular in seismic depth *** its straightforward 3. extension creates two-way splitting error due to ignoring the cross terms of spatial partial *** correction schemes,either in the spatial domain by the implicit finite -difference method or in the wavenumber domain by phase compensation,lead to substantially increased computational costs or numerical difficulties for strong velocity *** propose compensating the two-way splitting error in dual domains,alternately in the spatial and wave-number domains via Fourier ***,we organize the expanded square-root operator in terms of two-way splitting FFD plus the usually ignored cross ***,we select a group of optimized coefficients to maximize the accuracy of propagation in both inline and crossline directions without yet considering the diagonal ***,we further optimize the constant coefficient of the compensation part to further improve the overall accuracy of the operator. In implementation,the compensation terms are similar to the high-order corrections of the generalized-screen method, but their functions are to compensate the two-way splitting error rather than the expansion *** experiments show that optimized one-term compensation can achieve nearly perfect circular impulse responses and the propagation angle with less than 1%error for all azimuths is improved up to 60°from 3.°.Compared with traditional single-domain methods,our scheme can handle lateral velocity variations(even for strong velocity contrasts) much more easily with only one additional Fourier transform based on the two-way splitting FFD method,which helps retain the computational efficiency.

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Two stages power generation test of the hot dry rock exploration and production demonstration project in the Gonghe Basin,northeastern Qinghai-Tibet plateau,china

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china.geology 2024年第3期7卷 409-421页

作者： Er-yong zhang Dong-guang Wen Gui-ling Wang Xian-peng jin Lin-you zhang {3.-dong Wu Wen-shi Wang Cheng-ming Ye Wei Weng Kuan Li jin-sheng Wu Xian-chun Tang Chong-yuan zhang Qing-da Feng Sheng Lian Li-sha Hu Gui-lin Zhu xing-long Xie Bin Wu Dan Wang Xue Niu Zhao-xuan Niu Dong-lin Liu Hui zhang Wen-hao Xu Shu-qing yao Li Yang Center for Hydrogeology and Environmental geology Survey China Geological SurveyMinistry of Natural ResourcesTianjin 300304China Institute of Hydrogeology and Environmental geology Chinese Academy of Geological SciencesChina Geological SurveyShijiazhuang 050061China Institute of Exploration Techniques Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Institute of Exploration Engineering China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Institute of Exploration Technology Chinese Academy of Geological SciencesChengdu 611734China chinese academy of Geological sciences China Geological SurveyBeijing 100037China Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing 100081China Geoscience Documentation Center China Geological SurveyMinistry of Natural ResourcesBeijing 100083China

The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization *** HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture *** 2019,china.Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR *** the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in *** establishing the primary well group in the initial phase,two directional wells and one branch well were *** progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was ***,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology.

关键词： Power generation Hot dry rock(HDR) Enhanced geothermal system(EGS) Genesis mechanism Gonghe Basin Directional drilling Reservoir construction Circulation test Induced seismicity Clean energy exploration engineering

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Application of deep learning methods combined with physical background in wide field of view imaging atmospheric Cherenkov telescopes

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Nuclear Science and Techniques 2024年第4期35卷 208-220页

作者： Ao-Yan Cheng Hao Cai Shi Chen Tian-Lu Chen Xiang Dong You-Liang Feng Qi Gao Quan-Bu Gou Yi-Qing Guo Hong-Bo Hu Ming-Ming Kang hai-jin Li Chen Liu Mao-Yuan Liu Wei Liu Fang-Sheng Min Chu-Cheng Pan Bing-Qiang Qiao Xiang-Li Qian Hui-Ying Sun Yu-Chang Sun Ao-Bo Wang Xu Wang zhen Wang Guang-Guang Xin Yu-Hua {3. Qiang Yuan Yi zhang School of Physics and Technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan UniversityKunming 650091China Ministry of Education The Key Laboratory of Cosmic Rays(Tibet University)Lhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China College of Physics Sichuan UniversityChengdu 610064China School of Intelligent Engineering Shandong Management UniversityJinan 250357China Tsung‑Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China Suzhou Aerospace Information Research Institute Suzhou 215123China College of Physics Chongqing UniversityNo.55 Daxuecheng South RoadHigh‑tech DistrictChongqing 401331China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China

The High Altitude Detection of Astronomical Radiation(HADAR)experiment,which was constructed in Tibet,china.combines the wide-angle advantages of traditional EAS array detectors with the high-sensitivity advantages of focused Cherenkov *** objective is to observe transient sources such as gamma-ray bursts and the counterparts of gravitational *** study aims to utilize the latest AI technology to enhance the sensitivity of HADAR *** datasets and models with distinctive creativity were constructed by incorporating the relevant physical theories for various *** models can determine the type,energy,and direction of the incident particles after careful *** obtained a background identification accuracy of 98.6%,a relative energy reconstruction error of 10.0%,and an angular resolution of 0.22°in a test dataset at 10 *** findings demonstrate the significant potential for enhancing the precision and dependability of detector data analysis in astrophysical *** using deep learning techniques,the HADAR experiment’s observational sensitivity to the Crab Nebula has surpassed that of MAGIC and *** energies below 0.5 TeV and remains competitive with conventional narrow-field Cherenkov telescopes at higher *** addition,our experiment offers a new approach for dealing with strongly connected,scattered data.

关键词： VHE gamma-ray astronomy HADAR Deep learning Convolutional neural networks

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Optimized Chebyshev Fourier migration:A wide-angle dual-domain method for media with strong velocity contrasts

Optimized Chebyshev Fourier migration:A wide-angle dual-doma...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： jin-hai zhang,Wei-Min Wang,Shu-Qin Wang,and {3.-xing yao 1 chinese academy of sciences,Institute of geology and geophysics,beijing,china. 2 chinese academy of sciences,Institute of Tibetan Plateau Research,Key Laboratory of Continental Collision and Plateau Uplift,beijing,china. 3.Minzu University of china.Institute of Information Engineering,beijing,china.

A wide-angle propagator is essential when imaging complex media with strong lateral velocity contrasts in one-way wave-equation *** have developed a dual-domain one-way propagator using truncated Chebyshev polynomials and a globally optimized *** method increases the accuracy of the expanded square-root operator by adding two high-order terms to the traditional split-step Fourier ***,we approximate the square-root operator using Taylor expansion around the reference background ***,we apply the first-kind Chebyshev polynomials to economize the results of the Taylor ***,we optimize the constant coefficients using the globally optimized scheme,which are fixed and feasible for arbitrary velocity *** analysis and numerical experiments have demonstrated that the method has very high accuracy and exceeds the unoptimized Fourier finite-difference propagator for the entire range of practical velocity contrasts. The accurate propagation angle of the method is always about 60°under the relative error of 1%for complex media with weak,moderate,and even strong lateral velocity *** method allows us to handle wide-angle propagations and strong lateral velocity contrast simultaneously by using Fourier transform *** four 2D Fourier transforms are required for each step of 3. wavefield extrapolation,and the computing cost is similar to that of the Fourier finite-difference *** with the finite-difference method,our method has no two-way splitting error(i.e.,azimuthal-anisotropy error)for 3. cases and almost no numerical dispersion for coarse *** addition, it has strong potential to be accelerated when an enhanced fast Fourier transform algorithm emerges.

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3. Fourier finite-difference migration by alternating-direction-implicit plus interpolation

3D Fourier finite-difference migration by alternating-direct...

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中国科学院地质与地球物理研究所2008学术年会

作者： jin-hai zhang~*,Wei-Min Wang,Li-Yun Fu and {3.-xing yao Institute of geology and geophysics,chinese academy of sciences,beijing 100029,PR china

Conventional two-way splitting Fourier finite-difference migration for 3. complex media yields azimuthal anisotropy where an additional phase correction is needed with much increase of computational *** incorporate the alternating-direction-implicit plus interpolation scheme into the conventional Fourier finite-difference method to reduce azimuthal *** scheme retains the high-order remnants ignored by the two-way splitting in the form of a wavefield interpolation in the wavenumber *** wavefield interpolation for each step of downward extrapolation is implemented between the wavefields before and after the conventional Fourier finite-difference *** the Fourier finite-difference migration is implemented in the space and wavenumber dual space,the Fourier transforms between space and wavenumber domain that were needed for the alternating-direction-implicit plus interpolation in frequency domain(FD) migration are saved in Fourier finite-difference *** the azimuth anisotropy in Fourier finite-difference is much less than that in FD,the application of the alternating-direction-implicit plus interpolation scheme in Fourier finite-difference migration is superior to that in FD migration in handling complex media with large velocity contrasts and steep dips. Impulse responses show that the presented method reduces the azimuthal anisotropy at almost no extra cost.

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Seismic Lg-wave Q tomography in and around Northeast china

Seismic Lg-wave Q tomography in and around Northeast China

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Lian-Feng Zhao,Xiao-Bi Xie,Wei-Min Wang,jin-hai zhang,and {3.-xing yao 1 Institute of geology and geophysics,chinese academy of sciences, beijing,china. 2 Institute of geophysics and Planetary Physics,University of California, Santa Cruz,Santa Cruz,California,USA. 3.Institute of Tibetan Plateau Research,chinese academy of sciences, beijing,china.

[1]We investigate regional variations in the Lg-wave quality factor(Q)in Northeast china.and its vicinity with a tomographic *** seismic data recorded at 20 broadband stations from 125 regional events are used to extract Lg-wave spectra. Tomographic inversions are independently conducted at 58 discrete frequencies distributed log evenly between 0.05 and 10.0 *** simultaneously invert for the Lg-wave Q distribution and source spectra at individual frequencies without using any a priori assumption about the frequency dependence of the Q model and source *** best spatial resolution is approximately 1°×1°in well-covered areas for frequencies between 0.4 and 2.0 *** Lg Q shows significant regional variations and an apparent relationship with regional *** use a statistical method to investigate the regional variations of Lg Q and their frequency *** average Q(1 Hz Lg Q)in the entire investigated region is *** basins are usually characterized by lower average Q values (from 155 to 3.1),while volcanic mountain areas have relatively high average Q values (from 63. to 675).Lg Q generally increases with increasing ***,the frequency dependence has complex nonlinear features on a double-logarithmic scale, indicating that the commonly adopted power-law relationship may be oversimplified in a broad frequency *** frequency dependence varies in different geological areas,with larger variations seen at lower frequencies.

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Aeolian Facies Belts in the Taklimakan Desert

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 317-328页

作者： Li Baosheng, Dong Guangrong, zhang Jiasheng, Li Sen,jin Heling, Chen Huizhong, Wen Xiangle, Wang yao, Lanzhou Desert Research Institute, {3. academy of sciences, Lamhou, Gansuand Zhu YizhiXi’an Open Laboratory of Loess and Quaternary geology, {3. academy of sciences, Xi’an, Gansu Fei zhenbi Lanzhou Desert Research Institute Chinese Academy of Sciences Lanzhou Gansu China

At least at the beginning of the last glacial epoch, the facies belts of dune sand, sandy loam and loess formed by winds had existed in the Taklimakan desert and areas south of it. There were no appreciable changes in the NE and NW wind systems and their wind fqrces that deposited dune sand, sandy loam and loess in the global cold stage since the last glacial epoch (accordingly no marked shifts of the boundaries of these aeolian facies belts took place. In the global warm stage since then, the climate in the Taklimakan desert and areas south of it became warm and dry, resulting in ablation of substantial volumes of ice and snow in their surrounding mountains and thus forming alluvial and diluvial deposits in the region. The alluvial-diluvial actions, however, failed to change the general framework of aeolian facies belts.

关键词： Taklimakan desert sandy loam belt loess belt last glacial depositional environment

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鞘层电容对快速扫描双探针伏安曲线的影响

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核聚变与等离子体物理 2024年第2期44卷 198-205页

作者：孙海岗靳琛垚张炜江堤叶孜崇中国科学院合肥物质科学研究院等离子体物理研究所合肥230031 中国科学技术大学科学岛分院合肥230026

建造了基于多偶极腔体热阴极放电形式搭建的500kHz不对称快速扫描双探针系统,以电容对测量结果的影响进行实验研究。对不同扫描频率下不同尺寸的快速扫描不对称朗缪尔双探针受离子饱和电流及鞘电流影响的结果进行了对比分析。这项研究... 详细信息

建造了基于多偶极腔体热阴极放电形式搭建的500kHz不对称快速扫描双探针系统,以电容对测量结果的影响进行实验研究。对不同扫描频率下不同尺寸的快速扫描不对称朗缪尔双探针受离子饱和电流及鞘电流影响的结果进行了对比分析。这项研究对于不同扫描频率下快速扫描不对称双探针的选择应用有着参考和指导意义。

关键词：朗缪尔探针等离子体诊断鞘层电容

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新疆准噶尔盆地周边晚石炭世的珊瑚

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古生物学报 2024年第1期63卷 66-93页

作者：罗正江石国新林巍陈俊刘金白海枫梁昆要乐黄兴郄文昆王玥中国石油新疆油田分公司实验检测研究院新疆克拉玛依834000 中国科学院南京地质古生物研究所-中国石油新疆油田公司地层古生物联合实验室南京210008 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学北京100049

新疆北部准噶尔盆地周边石炭系广泛出露,其中上石炭统发育海相火山—沉积序列,包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组,东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎... 详细信息

新疆北部准噶尔盆地周边石炭系广泛出露,其中上石炭统发育海相火山—沉积序列,包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组,东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎屑岩中获得的四射珊瑚9属17种和床板珊瑚2属3.,对石钱滩组中的3.新种进行了详细的系统古生物学描述。上述珊瑚化石的地质时代主要为巴什基尔期至莫斯科期。在珊瑚动物群的组成上,哈拉阿拉特组中新发现Caninophyllum属分子,结合盆地东、西部共同产出的床板珊瑚Cystodendropora属分子,说明整个准噶尔盆地周边的动物群面貌大致类似,而西准噶尔地区的化石丰度、分异度显著低于盆地东部和东南部。综合前人资料,目前在准噶尔盆地周边发现的珊瑚化石有约一半为地方性分子。本文认为研究区珊瑚化石的分布和组成特征与晚石炭世准噶尔洋走向封闭或半封闭的演化趋势密切相关。

关键词：珊瑚石炭纪准噶尔盆地构造古地理意义

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