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Journal of Integrative Plant Biology 2006年第5期48卷 497-502页

作者： Rui Luo Chao wang daming Zhang State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

The localization of 18S ribosomal RNA genes （rDNA） by fluorescence in situ hybridization （FISH） had been performed for some species of Paeonla. However, the pattern of 18S rDNA loci among populations Is Indistinct. In the present study, we localized 18S rDNA loci on meiotic or mitotic chromosomes of six populations of Paeonla obovata Maxim. （Paeonlaceae）. Different numbers of rDNA loci were found with different diploid （2n=10） populations, namely eight （Lushl and Mt. JIuhua populations）, 10 （Mt. Talbal population）, and seven （Mt. Guandl population）, whereas tetraplold （2n=20） populations were all found with 16 loci. Aii rDNA loci were mapped near teiomeres of mitotic chromosomes and there was no chromosome with two loci. The present results show that molecular cytological polymorphlsm exists among P. obovata diploid populations, Indicating that structural variations occurred frequently during the evolutionary history of this species, accompanied with differentiation among populations.

关键词： cytotype fluorescence in situ hybridization (FISH) Paeonia obovata 18S rDNA tetraploid.

A New Example of Retrograde Solubility Model for Carbonate Rocks

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1145-1146页

作者： LIU Lihong wang Chunlian wang daming wang Haida Oil & Gas Survey China Geological Survey Oil and Gas Research Center School of Earth and Space SciencesPeking University MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences China Geological Survey

Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus during recent years. The most important dissolution fluids to carbonates are probably H2S and CO2 as byproducts of sulfate reduction in deep-buried setting with sulfate minerals, but carbonates are more soluble in relatively low temperature, which is the so-called retrograde solubility. Several geological processes can result in the decrease of temperature, including the upward migration of thermal fluids and tectonic uplift.

关键词： of on with well A New Example of Retrograde Solubility Model for Carbonate Rocks for

A direct position determination method with combined TDOA and FDOA based on particle filter

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Chinese Journal of Aeronautics 2018年第1期31卷 161-168页

作者： Zhiyu LU Bin BA Jianhui wang Wenchao LI daming wang China National Digital Switching System Engineering & Technological R&D Cente Zhengzhou 450000 China Jiuquan Satellite Launch Center Jiuquan 735000 China

The localization of a stationary transmitter using moving receivers is considered. The original Direct Position Determination （DPD） methods, with combined Time Difference of Arrival （TDOA） and Frequency Difference of Arrival （FDOA）, do not perform well under low Signal-to-Noise Ratio （SNR）, and worse still, the computation cost is difficult to accept when the computational capabilities are limited. To get better positioning performance, we present a new DPD algorithm that proves to be more computationally efficient and more precise for weak signals than the conventional approach. The algorithm partitions the signal received with the same receiver into multiple non-overlapping short-time signal segments, and then uses the TDOA, the FDOA and the coherency among the short-time signals to locate the target. The fast maximum likelihood estimation, one iterative method based on particle filter, is designed to solve the problem of high computation load. A secondary but important result is a derivation of closed-form expressions of the Cramer-Rao Lower Bound （CRLB）. The simulation results show that the algorithm proposed in this paper outperforms the traditional DPD algorithms with more accurate results and higher computational efficiency, and especially at low SNR, it is more close to the CRLB.

关键词： Direct position determination Cramer-Rao lower bound Frequency difference of arrival Time difference of arrival Particle filter

内蒙古中部碱长花岗岩型铌钽矿床典型岩矿光谱识别特征

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岩矿测试 2025年第1期44卷 102-114页

作者：汪翡翠汪大明栗旭升张博魏佳林曹思琦仝云霄中国地质调查局天津地质调查中心(华北地质科技创新中心) 天津300170

内蒙古中部地区,位于大兴安岭南段—华北陆块北缘成矿带,因其碱长花岗岩型铌钽矿的广泛分布而备受关注。尽管该地区铌钽矿资源丰富,但对其光谱学特征的系统认识尚不足,在一定程度上制约了矿产资源勘查的精确性和效率。本文以赵井沟大型... 详细信息

内蒙古中部地区,位于大兴安岭南段—华北陆块北缘成矿带,因其碱长花岗岩型铌钽矿的广泛分布而备受关注。尽管该地区铌钽矿资源丰富,但对其光谱学特征的系统认识尚不足,在一定程度上制约了矿产资源勘查的精确性和效率。本文以赵井沟大型铌钽矿床为例,利用便携式短波红外及热红外光谱仪对赵井沟典型岩矿样本开展光谱测量与分析,揭示富铌钽钠长花岗岩、天河石化钠长花岗岩、天河石伟晶岩、黑云母二长花岗岩、含黑钨矿石英脉波谱特征,并对其展开对比研究。研究表明:在近红外光谱范围内,与USGS光谱库中的标准钠长花岗岩光谱进行对比分析,发现2360nm处的弱吸收特征可作为天河石化钠长花岗岩与其他岩石及矿物区分的关键波段,此差异推测可能由岩石的蚀变矿化过程引起。在热红外光谱分析中,含黑钨矿石英脉因其显著的高反射率和“三峰”特征而易于区分与识别。尽管富铌钽钠长花岗岩、天河石伟晶岩和黑云母二长花岗岩在光谱形态上具有一定的相似性,但它们在2200nm附近的吸收深度的大小和峰强比的差异,为有效地区分这些矿物提供了重要依据。

关键词：铌钽矿光谱特征参数近红外光谱热红外光谱

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Direction finding for two-dimensional incoherently distributed sources with Hadamard shift invariance in non-uniform orthogonal arrays

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Chinese Journal of Aeronautics 2018年第12期31卷 2260-2269页

作者： Zhengliang DAI Weijia CUI daming wang Bin BA Chao wang Yankui ZHANG National Digital Switching System Engineering&Technological Research Center Zhengzhou 450001China

This paper proposes a novel algorithm for Two-Dimensional(2D) central Directionof-Arrival(DOA) estimation of incoherently distributed sources. In particular, an orthogonal array structure consisting of two Non-uniform Linear Arrays(NLAs) is considered. Based on first-order Taylor series approximation, the Generalized Array Manifold(GAM) model can first be established to separate the central DOAs from the original array manifold. Then, the Hadamard rotational invariance relationships inside the GAMs of two NLAs are identified. With the aid of such relationships, the central elevation and azimuth DOAs can be estimated through a search-free polynomial rooting method. Additionally, a simple parameter pairing of the estimated 2D angular parameters is also accomplished via the Hadamard rotational invariance relationship inside the GAM of the whole array. A secondary but important result is a derivation of closed-form expressions of the Cramer-Rao lower bound. The simulation results show that the proposed algorithm can achieve a remarkably higher precision at less complexity increment compared with the existing low-complexity methods, which benefits from the larger array aperture of the NLAs. Moreover, it requires no priori information about the angular distributed function.

关键词： Array signal processing Cramer-Rao lower bound Direction-of-Arrival(DOA) estimation Hadamard rotational invariance Incoherently distributed sources Non-uniform orthogonal array

A Highly Efficient ZrO2 Nanoparticle Based Electrochemical Sensor for the Detection of Organophosphorus Pesticides

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Chinese Journal of Chemistry 2015年第10期33卷 1135-1139页

作者： Haibo wang Yingchun Su Hojong Kim daming Yong Lei wang Xiaojun Han State Key Laboratory of Urban Water Resource and Environment School of Chemical Engineering and Technology Harbin Institute of Technology Harbin Heilong/iang 150001 China

A sensitive electrochemical method for square-wave voltammetric detection of organophosphate （OP） com- pounds was developed based on zirconia （ZrO2） nanoparticles modified electrode. The electrode was fabricated us- ing electrochemical deposition and characterized by scanning electron microscopy （SEM）, which confirmed the successful formation of nanoparticles. Due to the strong affinity of ZrO2 with the phosphoric group, OPs can strongly bind to the surface of ZrO2 nanoparticles （ZrO2NPs）. Under optimized operational conditions, SWV was employed for Omethoate （a model of OP compounds） detection with 5 min absorption, which showed a wide detec- tion range from 98.5 pmoloL-x to 985 nmol·L^1, with a detection limit as low as 52.5 pmol·L^-1. This electrochemi- cal sensor has good selectivity, stability and reproducibility, and great potential in the detection of OP compounds in agriculture area.

关键词： zirconia nanoparticles organophosphate pesticides Omethoate square wave voltammetry ITO

The Cause Analysis of College Student Human Capital Depreciation in China

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International English Education Research 2015年第9期 86-89页

作者： Wenhui Huang daming wang East China University of Science and Technology School of Business

Human capital depreciation can be divided into stock depreciation and utility depreciation, which will cause the waste of human capital investment, and let human capital value fail to fully embody, affecting social development. In the critical time of China facing population aging and economic transformation, as the new human capital of the labor market, college students play an important role to social and economic development. Therefore, preventing and mitigating their human capital depreciation is necessary. This article focus on human capital investment and configuration stage, analyze the influence of unreasonable human capital investment system and separate labor market segmentation system to college student human capital depreciation, and put forword the corresponding countermeasures.

关键词： Human Capital Depreciation Human Capital Investment Labor Market

Remote Detection of Hydrocarbon Microseepage in a Loess Covered Area

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Journal of Earth Science 2020年第1期31卷 207-214页

作者： Liang Zhao Darning wang Shengbo Chen Lin Li Tianyu Zhang College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026China Division of Petroleum Geology China Geological SurveyBeijing 100037China Department of Earth Sciences Indiana University-Purdue University IndianapolisIndianapolis 46202USA College of Earth Science Jilin UniversityChangchun 130061China

Hydrocarbon microseepage can result in related near-surface mineral *** this study,we evaluated the potential of detecting these alterations with field measured and satellite acquired hyperspectral *** soil samples and reflectance spectra were collected in the Xifeng Oilfield,a loess covered *** samples were analyzed in the laboratory for calcite,dolomite,kaolinite,illite,and mixedlayer illite/smectite content,and we processed reflectance spectra for continuum removal to derive clay and carbonate mineral absorption depth(H).High correlation between absorption depth and mineral content was shown for clay and mineral carbonate with field measured *** on the result for the field spectra,we proposed and tested a fast index based on the absorption depth of clay and carbonate minerals with a hyperspectral image of the *** detected hydrocarbon microseepage anomalies matched well with those shown in the geological map.

关键词： hyperspectral remote sensing hydrocarbon microseepage spectrum absorption parameters multiple regression analysis fast index geochemistry

Development and validation of a novel nomogram to predict aneurysm rupture in patients with multiple intracranial aneurysms:a multicentre retrospective study

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Stroke & Vascular Neurology 2021年第3期6卷 433-440,I0058-I0072页

作者： Xin Feng Xin Tong Fei Peng Hao Niu Peng Qi Jun Lu Yang Zhao Weitao Jin Zhongxue Wu Yuanli Zhao Aihua Liu daming wang Neurosurgery Department Beijing HospitalBeijingBeijingChina Neurointervention Center Beijing Neurosurgical InstituteBeijingChina Neurointervention Center Beijing Tiantan HospitalBeijingChina Neurosurgery Department Peking University International HospitalBeijingChina

Background and purpose Approximately 15%–45%of patients with unruptured intracranial aneurysms have multiple intracranial aneurysms(MIAs).Determining which one is most likely to rupture is extremely important for treatment decision making for MIAs *** study aimed to develop and validate a nomogram to evaluate the per-aneurysm rupture risk of MIAs *** A total of 1671 IAs from 700 patients with MIAs were randomly dichotomised into derivation and validation *** logistic regression analysis was used to select predictors and construct a nomogram model for aneurysm rupture risk assessment in the derivation *** discriminative accuracy,calibration performance and clinical usefulness of this nomogram were *** also developed a multivariate model for a subgroup of 158 subarachnoid haemorrhage(SAH)patients and compared its performance with the nomogram *** Multivariate analyses identified seven variables that were significantly associated with IA rupture(history of SAH,alcohol consumption,female sex,aspect ratio>1.5,posterior circulation,irregular shape and bifurcation location).The clinical and morphological-based MIAs(CMB-MIAs)nomogram model showed good calibration and discrimination(derivation set:area under the curve(AUC)=0.740 validation set:AUC=0.772).Decision curve analysis demonstrated that the nomogram was clinically *** with the nomogram model,the AUC of multivariate model developed from SAH patients had lower value of *** This CMB-MIAs nomogram for MIAs rupture risk is the first to be developed and validated in a large multi-institutional *** nomogram could be used in decision-making and risk stratification in MIAs patients.

关键词： rupture patients aneurysm

Background and Research Prospect of Geo-ecological Survey and Monitor in the Critical Zone of Black Soil

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 126-129页

作者： LI Zhizhong wang daming DAI Huimin wang Xisheng LIANG Shuai XU Jiang YANG Jiajia wang Lei CHEN Shengbo A lecos DEMETRIADES Veronika KOPACKOVA Igor SAVIN Douglas A.HOWARD Timothy FILLEY GENG Xiaoyuan Shenyang Geological Survey of China Geological Survey Shenyang 110030LiaoningChina China Geological Survey Beijing 100000China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100000China British Geological Survey Ctr Environm SciNottingham NG125GGEngland Jilin University Institute of Geology and Mineral Exploration Olympic VillageChangchun 130026JilinChina Czech Geological Survey Remote Sensing DepartmentPrague11821Czech Republic Russian Academy of Sciences Kirensky Institute of Physics Krasnoyarsk660036Russia Department of Geology Arizona State University TempeArizona85287-1404USA Purdue Univ Dept Earth Atmospher&Planetary Sci550 Stadium Mall DrW LafayetteIN 47907USA Kentville Research and Development Centre Agriculture and Agri-Food CanadaKentvilleNS B4N 1J5Cancda

The American Science journal,on the occasion of its 125 publication anniversary,in 2016,released 125 of the most challenging scientific issues(Kennedy et al.,2005)to the *** to the basics,breadth and the influence,25 of the issues which considered to be the most important were screened,including"How many people can the Earth carry?"(Stokstad,2005;Dailyg et al.,1992;Cohen,1995)and"How high will the greenhouse effect make the earth temperature?

关键词： black soils resource black soil critical zone earth critical zone