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Origin and genetic family of Huhehu oil in the Hailar Basin, northeast China

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Acta Geochimica 2018年第6期37卷 820-841页

作者： Yao-Ping Wang Fan Zhang Yan-Rong Zou Zhao-Wen Zhan Yulan Cai State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640People's Republic of China University of Chinese Academy of Sciences Beijing100049People's Republic of China Exploration and Development Research Institute of Daqing Oilfield PetroChinaDaqing163712People's Republic of China

The Huhehu Sag is one of the most important oil and gas depressions in the Hailar Basin. However, the origin of Huhehu oil is still controversial. Previous studies on source rocks have mainly focused on the Nantun Formation(K1 n); a few studies have investigated the Damoguaihe Formation(K1 d). Based on the Rock–Eval pyrolysis parameters, 172 drill cutting samples from the Huhehu Sag were analyzed to evaluate their geochemical characteristics. Based on the Rock–Eval data, the mudstones from the first member of the Damoguaihe Formation(K1 d1) and the second member of the Nantun Formation(K1 n2) have moderate to high hydrocarbon generation potential, while mudstones from the first member of the Nantun Formation(K1 n1) have poor to good hydrocarbon generation potential.Additionally, both the K1 n1 and K1 n2 coal members have poor to fair hydrocarbon generation potential, but the K1 n2 coal member has a better generative potential. Fifteen Huhehu oils were collected for molecular geochemical analyses to classify the oils into genetic families and to identify the source rock for each oil using chemometric methods. The Huhehu oils were classified into three groups with different maturity levels using hierarchical cluster analysis and principal component analysis. Group A oils(high maturity) are characterized by relatively moderate ratios of Pr/Ph, Pr/n-C17, and Ph/n-C18, as well as an abundance of C29 steranes, mainly derived from the K1 n2 and K1 n1 mudstone members. In comparison, group B oils(moderate maturity) have relatively low Pr/Ph ratios,moderate Pr/n-C17 and Ph/n-C18 ratios, and low concentrations of C29 steranes. Group C oils(low maturity) show relatively high ratios of Pr/Ph, Pr/n-C17, and Ph/n-C18, as well as high concentrations of C29 steranes. Furthermore,group B oils derived from the K1 d1 mudstone member and group C oils derived from the K1 n2 coal member were also identified by principal component analysis score plots.Correlation studies suggest a major contribution from the K1 n mudstone Formation and

关键词： Hailar Basin Huhehu Sag Biomarkers Chemometdcs Oil-oil and oil-source rock correlations

Heat Transfer Prediction of Supercritical Carbon Dioxide in Vertical Tube Based on Artificial Neural Networks

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Journal of Thermal Science 2021年第5期30卷 1751-1767页

作者： ZHU Bingguo ZHU Xinjie XIE Jian XU Jinliang LIU Huan Key Laboratory of Power Station Energy Transfer Conversion and System North China Electric Power UniversityMinistry of EducationBeijing102206China School of Mechanical&Electronical Engineering Lanzhou University of TechnologyLanzhou730050China Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy Utilization North China Electric Power UniversityBeijing102206China

Accurate prediction of supercritical CO_(2)(scCO_(2))heat transfer is important for heat exchanger design and safe operation of scCO_(2)power cycles.The main prediction method is empirical correlation.This paper demonstrates an alternative way by artificial neural networks(ANN)model with two hidden layers.To assess widely cited correlations and newly developed ANN model,scCO_(2)heat transfer experiment in vertical tube with pressure up to 20.8 MPa was performed to extend experiment database,which includes 2674 runs.Compared with empirical correlations,the ANN model is promising for following advantages:(1)ANN model has much better prediction accuracy.The mean relative error,mean absolute relative error and the root-mean-square relative error between predicted and measured wall temperatures are eA=0.38%,eR=4.88%and eS=7.29%,respectively.(2)ANN model performs faster computation speed.(3)ANN model can accurately and speedily predict scCO_(2)heat transfer performance for both normal heat transfer and heat transfer deterioration modes.The trained ANN program is provided with this paper,which is a useful tool and can be directly applied in engineering of scCO_(2)heat transfer.

关键词： supercritical CO_(2) heat transfer prediction ANN model correlations

Discretized Miller approach to assess effects on boundary layer ingestion induced distortion

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Chinese Journal of Aeronautics 2017年第1期30卷 235-248页

作者： Esteban Valencia Víctor Hidalgo Devaiah Nalianda Laskaridis Panagiotis Riti Singh Departamento de Ingeniería Mecánica Facultad de Ingeniería Mecánica Escuela Politécnica Nacional Ladron de Guevara E11-253 Quito 17-01-2759 Ecuador School of Engineering Cranfield University Bedford MK430AL United Kingdom

The performance of propulsion configurations with boundary layer ingestion（BLI） is affected to a large extent by the level of distortion in the inlet flow field. Through flow methods and parallel compressor have been used in the past to calculate the effects of this aerodynamic integration issue on the fan performance; however high-fidelity through flow methods are computationally expensive, which limits their use at preliminary design stage. On the other hand, parallel compressor has been developed to assess only circumferential distortion. This paper introduces a discretized semi-empirical performance method, which uses empirical correlations for blade and performance calculations. This tool discretizes the inlet region in radial and circumferential directions enabling the assessment of deterioration in fan performance caused by the combined effect of both distortion patterns. This paper initially studies the accuracy and suitability of the semiempirical discretized method by comparing its predictions with CFD and experimental data for a baseline case working under distorted and undistorted conditions. Then a test case is examined,which corresponds to the propulsor fan of a distributed propulsion system with BLI. The results obtained from the validation study show a good agreement with the experimental and CFD results under design point conditions.

关键词： BLI correlations Distortion Embedded propulsors Empirical Mean-line analysis Turbomachinery

Crystal-field levels of Nd3+ in a new langasite compound Nd3CrGe3Be2O14

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Journal of Rare Earths 2019年第11期37卷 1250-1254页

作者： Sergei A.Klimin Boris V.Mill Marina N.Popova Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia

We report on the crystal-field(CF)levels of Nd^3+in Nd3CrGe3Be2O14,a representative of recently synthesized Be-containing langasites.They are the first in the family to contain two magnetic subsystems,1 D chromium and Kagome-like rare-earth ones.High-resolution broad-band temperature-dependent spectra allow us to find all five CF Kramers doublets of the ground 4I9/2 CF multiplet and 38 levels of the excited 4I11/2,13/2,15/2,4F3/2,4F5/2+2H9/2,4F7/2+4S3/2 and 4F9/2 CF multiplets.These data form a basis for a future exploration of this interesting two-sublattice magnet with frustrated interactions.Optical transitions between Kramers doublets of Nd^3+indicate magnetic activity of 1D-chromium chains at T<20 K.

关键词： Langasite Two magnetic subsystems High-resolution spectroscopy Crystal-field levels Magnetic correlations Rare earths

Quasi-classical trajectory approach to the stereo-dynamics of the reaction F+HO→HF+O

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Science China Chemistry 2010年第4期53卷 927-932页

作者： Juan Zhao Yan Xu Xian Zhao QingTian Meng College of Physics and Electronics Shandong Normal University Jinan China State Key Laboratory of Crystal Materials Shandong University Jinan China

Quasi-classical trajectory (QCT) calculations are employed for the reaction F + HO(0,0)→HF + O based on the adiabatic potential energy surface (PES) of the ground 3A″triplet state. The average rotational alignment factor as a function of collision energy and the four polarization dependent generalized differential cross sections have been calculated in the center-of-mass (CM) frame, separately. The distribution P(θr) of the angle between k and j′, the distribution P(θr) of dihedral angle denoting k-k′-j′ correlation, and the angular distribution P(θr, Φr) of product rotational vectors in the form of polar plots are calculated as well. The effect of Heavy-Light-Heavy (HLH) mass combination and atom F's relatively strong absorbability to charges on the alignment and the orientation of product molecule HF rotational angular momentum vectors j′ is revealed.

关键词： product polarization F + HO reaction quasi-classical trajectory vector correlations

Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation

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Geoscience Frontiers 2018年第2期9卷 355-375页

作者： Yusuke Takamura Toshiaki Tsunogae M.Santosh Yukiyasu Tsutsumi Graduate School of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan Department of Geology University of JohannesburgAuckland Park 2006South Africa School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Centre for Tectonics Resources and Exploration Department of Earth SciencesUniversity of AdelaideSA 5005Australia Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki 305-0005Japan

The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late Meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late Mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). Meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern Madurai Block of southern India, and the central-western Madagascar could be alternative distal sources of the late Meso-to Neoproterozoic zircons. Paleo-to Mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have formed under similar tectonic regimes. We consider t

关键词： The northern Lützow-HolmeVijayan Complex Zircon UePb geochronology Crustal evolution Tectonic correlations Gondwana supercontinent

Quantifying nonclassicality of multimode bosonic fields via skew information

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Communications in Theoretical Physics 2021年第4期73卷 75-81页

作者： Yue Zhang Shunlong Luo Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Mesoscopic Physics School of PhysicsFrontiers Science Center for Nano-optoelectronicsPeking UniversityBeijing 100871China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

We quantify the nonclassicality of multimode bosonic field states by adopting an information-theoretic approach involving the Wigner-Yanase skew information.The fundamental properties of the quantifier such as convexity,superadditivity,monotonicity,and conservation relations are revealed.The quantifier is illustrated by a variety of typical examples,and applications to the quantification of nonclassical correlations are discussed.Various extensions are indicated.

关键词： Bosonic fields nonclassicality Wigner-Yanase skew information multimode states correlations

Genetics of carotenoids for provitamin A biofortification in tropical-adapted maize

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The Crop Journal 2016年第4期4卷 313-322页

作者： Alhassan D.Halilu Shehu G.Ado Daniel A.Aba Inuwa S.Usman Department of Plant Science Institute for Agricultural Research Ahmadu Bello University

Yellow maize contains high levels of β-carotene(βC), making it an important crop for combating vitamin A deficiency through biofortification. In this study, nine maize inbred lines were selected at random from 31 provitamin A(PVA) maize inbred lines and crossed in a partial diallel mating design to develop 36 crosses. The crosses were evaluated in the field in two locations(Samaru and Kerawa) and their seed carotenoid content were determined by high-performance liquid chromatography. The modes of gene action, heritability, and correlations between agronomic traits and carotenoid content were estimated. Additive genetic variances(σ~2a) were lower than non-additive genetic variances(σ~2d) for all the carotenoids, plant height(PH), and grain yield(GY), suggesting a preponderance of non-additive gene action. Broad-sense heritability(H^2) was high(H^2> 60%) for zeaxanthin,days to anthesis, and PH, moderate(30% correlations with carotenoid content, suggesting that these traits can be improved concurrently. Thus, there is ample scope for improvement of PVA and GY in the sample of tropical-adapted maize.

关键词： Biofortification Tropical-adapted maize Provitamin A Carotenoids Gene actions correlations

A pulse of the Earth: A 27.5-Myr underlying cycle in coordinated geological events over the last 260 Myr

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Geoscience Frontiers 2021年第6期12卷 236-242页

作者： Michael R.Rampino Ken Caldeira Yuhong Zhu Departments of Biology and Environmental Studies New York University100 Washington Square EastNew YorkNY 10003USA Department of Global Ecology Carnegie Institution for Science290 Panama StreetStanfordCA 94305USA Center for Data Science New York University60 Fifth AvenueNew YorkNY 10011USA

We performed spectral analyses on the ages of 89 well-dated major geological events of the last 260 Myr from the recent geologic literature. These events include times of marine and non-marine extinctions,major ocean-anoxic events, continental flood-basalt eruptions, sea-level fluctuations, global pulses of intraplate magmatism, and times of changes in seafloor-spreading rates and plate reorganizations. The aggregate of all 89 events shows ten clusters in the last 260 Myr, spaced at an average interval of ~ 26.9 Myr, and Fourier analysis of the data yields a spectral peak at 27.5 Myr at the ≥96% confidence level. A shorter period of ~ 8.9 Myr may also be significant in modulating the timing of geologic events.Our results suggest that global geologic events are generally correlated, and seem to come in pulses with an underlying ~ 27.5-Myr cycle. These cyclic pulses of tectonics and climate change may be the result of geophysical processes related to the dynamics of plate tectonics and mantle plumes, or might alternatively be paced by astronomical cycles associated with the Earth’s motions in the Solar System and the Galaxy.

关键词： Global geological events Fourier analysis Cyclic pulses Tectonics correlations