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Late Jurassic-Early Cretaceous Plutonism in the Northern Part of the Precambrian North China Craton:SHRIMP Zircon U-Pb Dating of Diorites and Granites from the Yunmengshan Geopark,Beijing

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 310-320页

作者： SHI Yuruo ZHAO Xitao MA Yinsheng HU Daogong LIU Qisheng WU Zhenhan ZHAO Yuanyi LIU Dunyi Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

The Yunmengshan Geopark in northern Beijing is located within the Yanshan range. It contains the Yunmengshan batholith, which is dominated by two plutons： the Yunmengshan gneissic granite and the Shicheng gneissic diorite. Four samples of the Yunmengshan gneissic granite give SHRIMP zircon U-Pb ages from 145 to 141 Ma, whereas four samples of the Shicheng gneissic diorite have ages from 159 Ma to 151 Ma. Dikes that cut the Yunmengshan diorite record SHRIMP zircon U-Pb age of 162±2 and 156±4 Ma. The cumulative plots of zircons from the diorites show a peak age of 155 Ma, without inherited zircon cores, and the peak age of 142 Ma for granite is interpreted as the emplacement age of the Yunmengshan granitic pluton, whose igneous zircons contain inherited zircon cores. The data presented here show that there were two pulses of magmatism： early diorites, followed c13 Ma later by true granites, which incorporated material from an older continental crust.

关键词： SHRIMP zircon U-Pb age Yunmengshan Geopark North China Craton

THE CRYSTAL STRUCTURE OF N-(TBUTOXYCARBONYL)-L-METHIONYL GLYCINE ETHYL ESTER

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Science in China,Ser.B 1985年第8期28卷 835-843页

作者：严友为董贻诚唐有祺 institute of Biophysics Academia Sinica Beijing

The crystal structure of N-（t-butoxycarbonyl）-L-methionyl-glycine ethyl ester has been determined. The crystal data are: P21, α=14.504（6）, b=5.015（2）, c=12.762（6）, β=93.63（3）°, Z=2. The final R is 0.066 for 1495 reflections. The torsion angles of methionyl side chain are X1=-177.7°. X2=178.6°, X3=-71.7°. The plan of the side chain is approximately vertical to the plan of the peptide. The peptide main chains are packed in a parallel β-sheet structure, the main chain torsion angles（φ,ψ） of the methionyl residue being （-118.9°,115.4°）. This compound, BOC-L-Met-Gly-OEt, is very similar to certain derivatives used in the peptide transport studies which were carried out by Naider et al.

关键词：卜工 L-METHIONYL GLYCINE ETHYL ESTER TBUTOXYCARBONYL THE CRYSTAL STRUCTURE OF N BOC

CAS-ESM2.0 dataset for the G1ext Experiment of the Geoengineering Model Intercomparison Project(GeoMIP)

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Advances in Atmospheric Sciences 2025年第3期 579-592页

作者： Min CUI Duoying JI John C.MOORE He ZHANG Jiangbo JIN Kece FEI Chenglai WU Jiawen ZHU Juanxiong HE Zhaoyang CHAI Dongling ZHANG College of Earth System Science Faculty of Geographical Science Beijing Normal University Arctic Centre University of Lapland International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences

Solar radiation modification, a scheme aimed at mitigating rapid global warming triggered by anthropogenic greenhouse gas emissions, has been explored through the G1ext experiment under the Geoengineering Model Intercomparison Project（GeoMIP） framework, utilizing the Chinese Academy of Sciences Earth System Model version 2（CAS-ESM2.0）. This paper briefly describes the basic configuration and experimental design of the CAS-ESM2.0 for G1ext, which involves a sudden reduction in solar irradiance to counterbalance the radiative forcing of an abrupt quadrupling of atmospheric CO2concentration, running for 100 years. Preliminary results show that this model can reproduce well the compensatory effect of a uniform decrease in global solar radiation on the radiative forcing resulting from an abrupt quadrupling of CO2concentration. Like other Earth system models, CAS-ESM2.0 reasonably captures variations in radiative adjustments, surface air temperature, and precipitation patterns, both globally and locally, under the G1ext scenario. The generated datasets have been released on the Earth System Grid Federation data server, providing insight into the potential efficacy and impact of solar geoengineering strategies.

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Introduction to the Special Issue on Blockchain Security

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 5-7页

作者： Zhihong Tian Yanhui Guo Shen Su Hui Lu Cyberspace institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Worcester Polytechnic institute Worcester01609-2280USA

Motivated by the fast evolvement of blockchain technology,cloud-edge platforms,intelligent transportation systems,smart grid,vehicular networks,location based services,and other IoT applications have achieved significant breakthrough during recent ***,blockchain based researches and projects are super-hot topics and focuses for both research and industrial ***,most of the current blockchain projects still suffer from insufficient security *** defects of the underlying protocol make the node communication vulnerable to be hijacked,and further exacerbate the fork problem;smart contracts can hardly be fully tested before deployment because of the evolving blockchain platforms,while the smart contracts updating is impossible(or very complicated);current data privacy protection techniques are either inefficient or inaccurate;sharing and cross-chain schemes brought new security problems together with its TPS *** intrinsic security vulnerabilities make the current blockchain based systems and architectures prone to be assaulted,and further do harm to the confidence of the investment on the blockchain *** still,blockchain turns out to play a critical role in a lot of existing security solutions,which would be useless if the blockchain is insecure.

关键词： services smart breakthrough

DISTRIBUTIONS OF CHEMICAL ELEMENTS WITH RELATION TO MAJOR WATER CIRCULATIONS IN THE CENTRAL AND NORTHERN PARTS OF THE TAIWAN STRAIT

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Chinese Journal of Oceanology and Limnology 1992年第2期10卷 168-177页

作者：陈水土张立平 Fujian institute of Oceanologv Xiamen 361012

data obtained from a comprehensive multidisciplinary oceanographic survey in the central and northern parts of the Taiwan Strait, 24°20′-26°00′N, 118°45°-121°00′E by the Fujian institute of Oceanology during the period May, 1983 through May, 1984, showed that the distributions of dissolved oxygen (DO), nitrate, dissolved inorganic phosphate and silicate concentrations here had obvious areal and seasonal characteristics that were mainly influenced by the seasonal circulation ofthree major water systems in the Taiwan Strait-- the Taiwan Strait Warm Water (TSWW), theZhejiang-Fujian Coastal Water (ZFCW), and the Northeastern Strait Warm Water (NESWW).

关键词： Taiwan Strait chemical elements distribution seasonal circulation water systems.

X-RAY STUDIES ON THE STRUCTURE OF DES-PENTAPEPTIDE INSULIN AT 2.4 RESOLUTION——THE REFINEMENT OF THE STRUCTURE

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Science in China,Ser.B 1984年第12期27卷 1265-1272页

作者：戴金璧楼美珍游俊明李家瑶王家槐梁栋材 institute of Biophysics Academia Sinica Beijing

The determination of an initial model for the crystal structure of des-pentapeptide in-sulin, using only the phase information obtained from the scattering of cadmium ions inthe native crystal, has been described. This paper describes the refinement of this modelagainst both the experimental X-ray observations and the a priori stereochemical observationsusing the method of restrained parameter least squares. The corrected and extended modelincluded not only all the non-hydrogen atoms of the protein and one cadmium ion, but alsosome 49 water molecules. Fourier syntheses using amplitudes of 2F_o-F_c, phase angles prob-abilistically combined from the anomalous scattering and model phase information, witheach term weighted according to its reliability gave clear results without detectable bias to-wards the current model. The final model has acceptable stereochemistry (root mean squaredeviation from ideal bond lengths 0.027 A), and predicts the observed X-ray scattering sat-isfactorily (R = 0.182 for all dat

关键词： THE REFINEMENT OF THE STRUCTURE X-RAY STUDIES ON THE STRUCTURE OF DES-PENTAPEPTIDE INSULIN AT 2.4 RESOLUTION maps AT DES

Audio-visual emotion recognition with multilayer boosted HMM

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Journal of Beijing institute of Technology 2013年第1期22卷 89-93页

作者：吕坤贾云得张欣 School of Software Beijing Institute of Technology Beijing Lab of Intelligent Information Technology School of Computer ScienceBeijing Institute of Technology

Emotion recognition has become an important task of modern human-computer interac- tion. A multilayer boosted HMM （ MBHMM ） classifier for automatic audio-visual emotion recognition is presented in this paper. A modified Baum-Welch algorithm is proposed for component HMM learn- ing and adaptive boosting （AdaBoost） is used to train ensemble classifiers for different layers （cues）. Except for the first layer, the initial weights of training samples in current layer are decided by recognition results of the ensemble classifier in the upper layer. Thus the training procedure using current cue can focus more on the difficult samples according to the previous cue. Our MBHMM clas- sifier is combined by these ensemble classifiers and takes advantage of the complementary informa- tion from multiple cues and modalities. Experimental results on audio-visual emotion data collected in Wizard of Oz scenarios and labeled under two types of emotion category sets demonstrate that our approach is effective and promising.

关键词： emotion recognition audio-visual fusion Baum-Welch algorithm multilayer boostedHMM Wizard of Oz scenario

EXTENDED GABOR FUNCTION MODEL AND SIMULATION OF SOME CHARACTERISTIC CURVES OF RECEPTIVE FIELD

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Science China Chemistry 1988年第10期31卷 1185-1194页

作者：汪云九齐翔林刑静于德山 Academia Sinica Beijing institute of Biophysics

In this paper we propose a family of extended Gabor functions as weight functions of the primary information processing in the visual system. The orientation tuning curve, the length tuning curve and spatial frequency tuning characteristics of simple cells, complex cells and some hypercomplex cells were simulated by means of our model. The results calculated by this model coincide closely with the experimental data. It has been shown that the extended Gabor function model can reasonably describe the main properties of receptive fields several levels of the visual system.

关键词： Gabor function receptive field tuning curve.

STRUCTURAL EFFECT IN FORKED CONJUGATIVE SYSTEMS——BIFURCATION-TYPE OF FORKED POLYENIC NITRILES,CARBOXYLIC ACIDS AND ESTERS

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Science China Chemistry 1982年第10期29卷 1021-1034页

作者：戴萃辰岳振洁蒋明谦 institute of Chemistry Academia Sinica Beijing

Five homologous series of bifurcate systems of aliphatic and aromatic polyenic cyano and carboxylic compounds have been prepared and studied. The electronic absorption spectra forthe series and the NMR chemical shifts for the methyl-, methylene- and beta-protons havebeen found to conform very well to the rule of homologous linearity. The mass spectra forthe α-cyano polyenic ester series show strong peaks for the fragments of M-COOEt but noneof M-CN, indicating that the CN group seems to be in stronger conjugation with the poly-enic chain than the COOEt group does. In all the forked series studided, a red shift in electronic spectra is brought about upon the introduction of an electron-attractive branching group, just like the case of introducing an electron-repelling substituent. This has been taken as an indication of the predominance of themolecular integrality over the group characteristics. By means of the method of similar triangles between a homologous line for a linearseries and that for the corresponding forked compounds, the equivalent △Ns for a branching group may be calculated with accuracy. Based on the value of this equivalent, the substituentnature of the structural effect of the branching group has been inferred. The electronic absorption maxima for four series of the forked compounds have been cal-culated by means of the extended homologous equation for the corresponding linear *** an appropriate correction for the positional effect of the substituent equivalent, the cal-culated wavelengths agree generally with experimental data within ± 7nm.

关键词： OCH BIFURCATION-TYPE OF FORKED POLYENIC NITRILES,CARBOXYLIC ACIDS AND ESTERS STRUCTURAL EFFECT IN FORKED CONJUGATIVE SYSTEMS CNY