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The discovery of Late Triassic hypabyssal mafic dykes in the Huozhou complex and their geological significance:Evidence from petrology,geochemistry,and geochronology

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Acta Geochimica 2024年第6期43卷 1013-1036页

The Huozhou complex in the Trans-North China Orogen exhibits two events of mafic magmatism(separated by ca.700 Ma):Neoproterozoic(920±15 Ma)Shimenyu diabase and Late Triassic(217±2.5 Ma)Xingtangsi *** have focused on systematic petrology,zircon U-Pb dating,Lu-Hf isotopes,and *** research findings indicate that the Late Triassic Xingtangsi diabase of the Huozhou complex can be classified as a transitional type between intermediate and mafic rocks based on their SiO_(2)*** classification is supported by an average SiO_(2)content of 53.94%,ranging from 53.33%to 54.28%.In the Zr/TiO_(2)*** diagram,all samples lie within the range of *** zircons from the Late Triassic Xingtangsi diabase have lowε_(Hf)(t)values ranging from-12.7 to-8.7,with an average ***,the single-stage model age T_(DM1)is estimated to be between 1207 and 1701 *** findings suggest that the magma responsible for the dyke originated from either partial melting or an enriched mantle source inside the Meso-Proterozoic lithospheric *** elevated concentrations of Th(thorium)and LREEs(light rare earth elements),as well as the Th/Yb and Th/Nb ratios,suggest the potential incorporation of subducted sediments within the magma source *** rock displays negative Nb,Ta,Zr,Hf,and Ti *** geochemical attributes align with the distinctive traits observed in volcanic rocks found within island *** formation of the Late Triassic Xingtangsi diabase is likely associated with the geological context of an arc setting,which arises from the collision between the Yangtze plate and the North China Craton.

关键词： Trans-North China Orogen Huozhou complex Geochemistry Hf isotope North China Craton

On statistical energy functions for biomolecular modeling and design

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Frontiers of Electrical and Electronic Engineering in China 2015年第4期10卷 157-167页

作者： haiyan liu School of Life Sciences Hefei National Laboratory for Physical Sciences at the Microscales and Collaborative Innovation Centerof Chemistry for Life Sciences University of Science and Technology of China Hefei 230027 China Hefei Institutes of PhysicalScience Chinese Academy of Sciences Hefei 230027 China

Statistical energy functions are general models about atomic or residue-level interactions in biomolecules, derived from existing experimental data. They provide quantitative foundations for structural modeling as well as for structure-based protein sequence design. Statistical energy functions can be derived computationally either based on statistical distributions or based on variational assumptions. We present overviews on the theoretical assumptions underlying the various types of approaches. Theoretical considerations underlying important pragmatic choices are discussed.

关键词： potential of mean forces statistical distribution optimization correlated variable reference state

The generalized quasi-variational principles of non-conservative systems with two kinds of variables

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Science China(Physics,Mechanics & Astronomy) 2005年第5期48卷 600-613页

作者： LIANG Lifu liu Diankui SONG haiyan School of Civil Engineering Harbin Engineering University Harbin 150001 China School of Civil Engineering Harbin Engineering University Harbin 150001 China School of Civil Engineering Harbin Engineering University Harbin 150001 China

According to the corresponding relations between general forces and general displacements, the balancing and geometrical equations of elasticity are multiplied by the corresponding virtual quantities, integrated with volume and area, and then added algebraically. Proceeding to the next step, by substituting constitutive relation and considering that body force and surface force are both fellow forces, the generalized quasi-variational principles with the two kinds of variables of the first type are established in non-conservative systems. Through substituting another constitutive relation, using similar methods as above, the generalized quasi-variational principles with the two kinds of variables of the second type are established in non-conservative systems. By using the generalized quasi-complementary energy principles with the two kinds of variables of the first type, a method for solving two kinds of variables (internal force and deformation) is given for non-conservative systems of the typical fellow forces.

关键词： non-conservative system, generalized variational principle, two kinds of variables.

Epidemic Spreading–Information Dissemination Coupling Mechanism in Heterogeneous Areas

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Computers, Materials & Continua 2021年第6期67卷 3311-3327页

作者： Yang Yang haiyan liu Jianlin Zhou School of Economics and Management China University of Geosciences(Beijing)Beijing100083China

With COVID-19 continuing to rage around the world,there is a spread of epidemic-related information on social networking *** phenomenon may inhibit or promote the scale of epidemic *** study constructed a double-layer epidemic spreading–information dissemination network based on the movements of individuals across regions to analyze the dynamic evolution and coupling mechanism of information dissemination and epidemic *** also proposed measures to control the spread of the epidemic by analyzing the factors affecting dynamic *** constructed a state probability equation based on Markov chain theory and performed Monte Carlo simulations to demonstrate the interaction between information dissemination and epidemic *** simulation results showed that the higher the information dissemination rate,the larger the scale of information dissemination and the smaller the scale of epidemic *** addition,the higher the recovery rate of the epidemic or the lower the infection rate of the epidemic,the smaller the scale of information dissemination and the smaller the scale of epidemic ***,the greater the probability of individuals moving across regions,the larger the spread of the epidemic and ***,the higher the probability of an individual taking preventive behavior,the smaller the spread of the epidemic and ***,it is possible to suppress epidemic spread by increasing the information dissemination rate,epidemic recovery rate,and probability of individuals taking preventive behavior,while also reducing the infection rate of the epidemic and appropriately implementing regional blockades.

关键词： Coupling mechanism moving and regional individuals heterogenous areas double-layer coupling network

Tuning of the active phase structure and hydrofining performance of alumina-supported tri-metallic WMoNi catalysts via phosphorus incorporation

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 59-69页

作者： Shufeng Shan haiyan liu Gang Shi Xiaojun Bao State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China State Key Laboratory of Energy & Environmental Photocatalysis Fuzhou University Fuzhou 350116 China

The effects of phosphorus on the structure and hydrofining performance of tri-metallic WMoNi/Al2O3 catalysts prepared with W/Mo-based hybrid precursor nanocrystals were investigated. The incorporation of phosphorus weakened the metal-support interactions （MSIs） and facilitated the formation of more synergetic NiWMoS phases with higher stacks. Catalytic tests using a fluid catalytic cracking diesel fuel showed that the changes in the MSIs and the morphology of the active phases had a more positive effect on the hydrodenitrogenation activity than on the hydrodesulfurization activity. In contrast, when phosphorus was incorporated into a tri-metallic WMoNiP/Al2O3 catalyst prepared by a conventional incipient impregnation method, the MSIs decreased causing aggregation of the metal species which resulted in poorer hydrofining performance of the catalyst. These results show that incorporating phosphorus into a WMoNi/Al2O3 catalyst can finely tune the structure of the active phase to enhance the hydrogenation and hydrodenitrogenation activity of the resulting tri-metallic catalyst.

关键词： fluid catalytic cracking diesel hydrofining performance WMoNiP/Al2O3 synergetic effect and structure of NiWMoS phases

Reaction performance of fluidized bed catalytic reactor of Group C^(+)particles

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Particuology 2021年第1期19卷 5-16页

作者： Zhiwei Zhao Yandaizi Zhou Xiaojun Bao Jesse Zhu haiyan liu State Key Laboratory of Heavy Oil Processing Department of Chemical EngineeringChina University of PetroleumBeijing 102249China Particle Technology Research Center Department of Chemical and Biochemical EngineeringThe University of Western OntarioLondonOntario N6A 5B9Canada

Group C particles are often regarded as non-fluidizable but have proven to effectively fluidize with nanoparticle addition,which results in small bubbles and a high gas holdup in the dense phase during the *** C^(+)particles provide an increased surface area for gas-solid contact and improve the reaction performance,especially for gas-phase catalytic *** the basis of a previous study of the ozone decomposition reaction using Group C^(+)particles,a two-phase model was used to evaluate the reactor contact efficiency,and was used to compare the partial oxidation performance of the n-butane to maleic anhydride reaction in fluidized-bed catalytic reactors of Group C^(+)and Group A *** reactor with Group C^(+)particles achieved a higher n-butane conversion and MAN yield compared with that using Group A particles,based on the identical catalyst quantity or on the same gas residence ***,the reactor with Group C^(+)particles can achieve the same reaction conversion and yield with fewer catalysts or a smaller reactor size,or ***,the fluidized bed catalytic reactor of Group C^(+)particles is expected to be of major significance in industrial processes,especially for gas-phase catalytic reactions.

关键词： Group C^(+)particles Fluidized bed catalytic reactor Reactor performance Nanoparticles Modified two-phase model Effective surface area

Mesoporogen-free synthesis of hierarchical sodalite as a solid base catalyst from sub-molten salt-activated aluminosilicate

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Particuology 2020年第1期18卷 48-54页

作者： Jinbiao Yang Tiesen Li Xiaojun Bao Yuanyuan Yue haiyan liu State Key Laboratory of Heavy Oil Processing China University of Petroleum18 Fuxue RoadBeijing 102249China East-China Design Branch China Petroleum Engineering&Construction Corporation2 Huayan RoadQingdao 266071China National Engineering Research Center of Chemical Fertilizer College of Chemical EngineeringFuzhou University2 Xueyuan RoadFuzhou 350116China

A rapid and environmentally friendly approach to synthesize hierarchical sodalite from natural aluminosilicate mineral without the involvement of any mesoporogen or post-synthesis treatment was *** strategy involves three important steps:the first is the depolymerization of an aluminosilicate mineral into highly reactive silicon and aluminum species with ideal meso-scale structures through activation of a sub-molten *** second step is the hydrolysis and condensation of the activated aluminosilicate mineral into zeolitic precursors that also have a meso-scale *** third is the rapid zeolitization of the zeolitic precursors through the reversed crystal growth route at room temperature and ambient pressure to form hierarchical *** physicochemical properties of the as-synthesized sodalite were systematically characterized,and the formation mechanism of the hierarchical pore structure was *** used as a solid base catalyst for Knoevenagel condensation,the as-synthesized sodalite and its potassium ion-exchanged product with hierarchical micro-meso-macroporous structure both exhibited high catalytic activity and product selectivity.

关键词： Natural aluminosilicate mineral Hierarchical sodalite Reversed crystal growth route Kirkendall effect Solid base catalyst Knoevenagel condensation

Effects of Feeding Time on the Growth Performance and Variation of RNA/DNA Ratio of the Chinese Soft-shelled Turtle, Pelodiscus sinensis

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Asian Herpetological Research 2016年第4期7卷 271-277页

作者： Yingguang jI haiyan liu Zhe SONG Zhencai YANG College of Life Science Hebei Normal University Shijiazhuang 050024 Hebei China Hebei Chemical and Pharmaceutical College Shijiazhang 050026 Hebei China

The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L （light）： 12D （dark） with lights on at 06：00 and off at 18：00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtles each （Initial body weight 88.27 - 0.09 g）. Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12：00 were the lowest from the six groups （P 〈 0.05）. Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight （FBW）, higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.

关键词： Feeding time Growth performance Pelodiscus sinensis RNA/DNA ratio

The net primary productivity of Mid-Jurassic peatland and its control factors: Evidenced by the Ordos Basin

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International Journal of Mining Science and Technology 2018年第2期28卷 177-185页

作者： Wang Dongdong Yan Zhiming liu haiyan Lv Dawei Hou Yijun College of Earth Science and Engineering Shandong University of Science and Technology College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)

Using the large-scale thick 4# coal seam from the Mid-Jurassic in the southern Ordos Basin as an example, this paper studied the net primary productivity(NPP) level of the Mid-Jurassic peatland, and discussed its control factors. Geophysical logging signals were used for a spectrum analysis to obtain the Milankovitch cycle parameters in coal seam. These were then used to calculate the accumulation rate of the residual carbon in 4# coal seam. The carbon loss can be calculated according to the density and residual carbon content of 4# coal seam. Then, the total carbon accumulation rate of the peatland was further derived, and the NPP of peatland was determined. The results show that the NPP of MidJurassic peatland is higher than that of Holocene at the same latitude. Comprehensive analysis indicates that the temperature, carbon dioxide and oxygen levels in atmosphere are the main control factors of the NPP of Mid-Jurassic peatland.

关键词： Net primary productivity(NPP) Peatland Milankovitch cycle Carbon accumulation rate Mid-Jurassic