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Acta Geologica Sinica(English Edition) 2007年第3期81卷 433-441页

作者： b.i guoping John b. KEENE Key Laboratory for Hydrocarbon Accumulation of Education Ministry China University of Petroleum Beijing 102249 China School of Geosciences University of Sydney NSW 2006 Australia

The fluid flow history during diagenesis of sandstones in the Upper Permian black Jack Formation of the Gunnedah basin has been investigated through integrated petrographic observations, fluid inclusion investigations and stable isotope analyses. The early precipitation of mixed-layer illite/smectite, siderite, calcite, ankerite and kaolin proceeded at the presence of Late Permian connate meteoric waters at temperatures of up to 60℃. These evolved connate pore waters were also parental to quartz, which formed at temperatures of up to 87℃. The phase of maximum burial was characterized by development of filamentous illite and late calcite at temperatures of up to -90℃. Subsequent uplifting and cooling led to deep meteoric influx from surface, which in turn resulted in dissolution of labile grains and carbonate cements, and formation of second generation of kaolin. Dawsonite was the last diagenetic mineral precipitated and its formation is genetically related to deep-seated mamagtic sourced CO2.

关键词： diagenesis fluid flow history Gunnedah basin fluid inclusion stable isotope

H型试剂对于大直径泥水盾构泥水分离处理的影响与应用

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岩土工程学报 2025年第1期47卷 153-163页

作者：张箭任国平尹义豪钟小春张春雷梁禹河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 中铁十四局集团大盾构工程有限公司江苏南京211800 河海大学环境学院江苏南京210098 中山大学土木工程学院广东珠海519082

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta... 详细信息

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta电位等变化规律,综合评价H型试剂与3种聚丙烯酰胺(PAM)在泥浆脱水效果方面的差异。结果表明:H型试剂与泥浆作用的最优添加量为0.5%;与PAM相比,H型试剂前期沉降速度较慢,但脱水后的泥渣含水率降低了约18.1%,且上清液非常清澈,7.8的pH值符合直接外排条件;H型试剂兼具了较好的桥网作用与电中和作用,使粒径<10μm的细粒更容易聚集成50μm以上的大颗粒,加快了泥浆的絮凝速度。H型试剂营造了渗水性更强的Ca排水通道,降低泥浆的黏滞性,提高泥浆压滤脱水的效率;与原脱水试剂相比,现场使用0.1%的H型试剂,可提高30.5%的脱水泥样含固率,降低20%的工程成本。

关键词：泥水盾构泥水分离絮凝脱水机理研究现场试验

Theoretical Study on ionic Liquid based on 1-Ethyl-3-Methylimidazolium Cation and Hexafluorophosphate or Tetrafluoroborate

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Journal of Natural Gas Chemistry 2007年第4期16卷 428-436页

作者： Renqing LU Zuogang Cao guoping Shen College of Chemistry and Chemical Engineering China University of Petroleum （East China） Dongying 257061 Shandong China

The Hartree-Fock and DFT/b3LYP methods have been employed to investigate the electronic structures of 1-ethyl-3-methyl-imidazolium cation （EMiM＋）, bF4^-, PF6^-, EMiM＋bF4^-, and EMiM＋-PF6^- using the Gaussian-94 soft-package at 6-31＋G（d,p） basis set level for hydrogen, carbon, nitrogen, boron, phosphorus, and fluorine atoms. Comparison of the electronic structures of the lowest energy of EMiM＋- bF4^- and EMiM＋-PF6^- pairs, and single EMiM＋, bF4^- and PF6^- showed that the optimized EMiM＋-bF4^- and EMiM＋-PF6^- pair conformers were bF4^- and PF6^- outside the 5-ring plane between the ethyl group and the methyl group. The cohesion of C H. … F hydrogen bond between cation and anion is reinforced by charge assistance. The interaction energy between EMiM＋ and PF6 is 328.8 kJ/mol at the b3LYP level and 326.6 kJ/mol at the Hartree-Fock level, whereas that between EMiM＋ and bF4 is 353.5 kJ/mol at the b3LYP level and 350.5 kJ/mol at the Hartree-Fock level. The low energy interactions caused by bulky asymmetric EMiM＋, and charge dispersion of cation and anion give rise to the low melting point of ionic liquid EMiM＋-bF4^- and EMiM＋-PF6^-. The two hydrogen bonding models of single hydrogen bond formation, and the hydrogen transfer between C2 in EMiM＋ and F in bF4^- or PF6^- were principally depicted.

关键词： Hartree-Fock density functional theory ionic liquid EMiM+ PF6^- bF4^-

Optical waveguide in curved and welded perovskite nanowires

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Science China(Technological Sciences) 2023年第5期66卷 1471-1479页

作者： ZHANG ZhenYu ZHANG YuPeng HONG binbin WANG guoping College of Electronics and information Engineering Shenzhen UniversityShenzhen 518060China

Single-crystalline lead halide perovskite nanowires are emerging as promising one-dimensional blocks for nanoscience and nanotechnology,and extensive studies of nano-lasers and nano-photodetectors have been ***,as perfect confined structures,their optical waveguide performances have not been widely paid attention to up to ***,we report on the such issue on single-crystalline CsPbbr3nanowires and quantify it by near-field optical response *** waveguide is verified as total internal reflection mode at the visible band(532 nm),and its far-field end-facet coupling efficiency of 89.6%and propagation loss as low as 5.9 db/mm are measured from the nanowire with cross-sectional geometry of~600 nm×300 *** evident bending loss exists in naturally curved nanowires,while it usually emerges in artificial-bended ones due to the wrinkled *** welded nanowire networks show significant advantages in integrated waveguides over the artificial assembled ones,due to the coupled photons at the space-confined end-facet *** surface reasoned by lattice degradation is detrimental to propagation loss,but it provides leaked channels for waveguide coupling on nanowire *** work studies the optical waveguide performance of perovskite nanowires with different geometries and goes a step further for integrated nanophotonics.

关键词： optical waveguide perovskite nanowires SNOM curved nanowire welded networks

Micromechanical testing and property upscaling of planetary rocks:A critical review

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international Journal of Mining Science and Technology 2024年第9期34卷 1217-1241页

作者： Yiwei Liu guoping Zhang Jiangmei Qiao Xuhai Tang School of Civil Engineering Wuhan UniversityWuhan 430072China Wuhan University Shenzhen Research institute Shenzhen 518108China Department of Civil and Environmental Engineering University of Massachusetts AmherstAmherstMA 01003USA

Knowledge of the mechanical behavior of planetary rocks is indispensable for space *** scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representative samples for conventional macroscale rock mechanics experiments(macro-RMEs).This critical review discusses recent advances in microscale RMEs(micro-RMEs)techniques and the upscaling methods for extracting mechanical *** of mineralogical and microstructural analyses,along with non-destructive mechanical techniques,have provided new opportunities for studying planetary rocks with unprecedented precision and ***,we summarize several mainstream methods for obtaining the mineralogy and microstructure of planetary ***,nondestructive micromechanical testing methods,nanoindentation and atomic force microscopy(AFM),are detailed reviewed,illustrating the principles,advantages,influencing factors,and available testing results from ***,several feasible upscaling methods that b.idge the micro-measurements of meteorite pieces to the strength of the intact body are ***,the potential applications of planetary rock mechanics research to guiding the design and execution of space missions are environed,ranging from sample return missions and planetary defense to extraterrestrial *** discussions are expected to broaden the understanding of the microscale mechanical properties of planetary rocks and their significant role in deep space exploration.

关键词： Meteorites Planetary rock mechanics Non-destructive testing Upscaling method Extraterrestrial construction Space exploration

TiME DOMAiN SOLUTiON OF UNSTEADY FLOW AROUND A SHiP

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Journal of Hydrodynamics 1998年第4期10卷 7-15页

作者： Li, Yile Liu, Yingzhong Miao, guoping Shanghai Jiaotong Univ Shanghai China

The unsteady flow around a ship advancing at a constant speed was studied in time domain by using a higher-order boundary element method. The Rankine source was employed. The ship hull and free surface were discretized into 8-node isoparametric elements. A modified Green formula was used to overcome the numerical difficulty arising from singular or quasi-singular integral equation. in the case of τ>0.25, a rigid wall condition was applied to the upstream and a numerical beach was applied to the downstream to absorb the outgoing waves. The numerical results are satisfactory compared with the experimental results.

关键词： boundary element method Computer simulation Flow of water Ships Time domain analysis Unsteady flow

DEM analysis of passive arching in a shallow trapdoor under eccentric loading

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Particuology 2023年第6期77卷 14-28页

作者： Ruixiao Zhang Dong Su Xingtao Lin guoping Lei Xiangsheng Chen Key Laboratory for Resilient infrastructures of Coastal Cities(MOE) Shenzhen UniversityShenzhen518060China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China Shenzhen Key Laboratory of Green Efficient and Intelligent Construction of Underground Metro StationShenzhen UniversityShenzhen518060China School of Transportation Civil Engineering&ArchitectureFoshan UniversityFoshan528225China

This study analyzed the passive arching effect under eccentric loading by developing a series of trapdoor discrete numerical *** numerical models were validated by comparison with laboratory test *** deformation pattern,soil arching ratio,force chain distribution,and coordination number under various surcharge magnitudes and deviation distances were *** numerical results showed that the deformation diagram of soil particles can be divided into three zones:principal displacement zone,transition zone,and static *** an increase in the surcharge magnitude,the range of the principal displacement zone decreased,but the range of the transition region *** curve of the soil arching ratio on the trapdoor can be divided into three phases,which can be well characterized by the tangent *** passive arching effect is degraded by a *** ulti-mate soil arching ratio could be approximated as a W-shaped distribution along the+*** an increase in the trapdoor displacement,the force chain on the trapdoor gradually expanded outward to form an inverted funnel *** most powerful force on the trapdoor was mainly distributed on its *** average coordination number decreased gradually as the trapdoor moved upward.

关键词： Passive arching Eccentric load Discrete element method Forcechaindistribution Trapdoorapparatus

The Density Functional Study of Thiophene Adsorption on Zeolite Clusters

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China Petroleum Processing & Petrochemical Technology 2007年第1期9卷 47-52页

作者： Lue Renqing Cao Zuogang Shen guoping College of Chemistry and Chemical Engineering China University of Petroleum （East China） Dongying 257061

The density functional theory and the cluster model methods have been employed to investigate the interactions between thiophene and the HZSM-5 zeolites. The molecular complexes formed by the adsorption of thiophene on silanol H3SiOH with two coordination forms, and the model brrnsted acid sites of zeolite cluster H3Si（OH）Ai（OH）2SiH3 upon the interaction with thiophene have been comparatively studied. Full optimization and frequency analysis of all cluster models have been carried out using the b3LYP hyb.id method at 6-31G basis level for hydrogen atoms and 6-31＋G（d） basis set level for silicon, aluminum, oxygen, carbon, and sulfur atoms. The calculated results showed that the nature of interactions leading to the formation of the zeolite cluster-thiophene and silanol-thiophene complexes was associated with the van der Waals force confirmed by a slight change of geometric structures and properties. Thiophene is adsorbed on b.idging hydroxyl group prior to silanol OH group judging from the magnitude of adsorption heat. The cluster model calculation reproducing the experimental prediction to form the experimental adsorption spectra of thiophene in HZSM-5 zeolite has illustrated the validity of the proposed adsorption models.

关键词： density functional theory thiophene ZSM-5 zeolite model cluster

A first-principles study of the structural,electronic and elastic properties of solid nitromethane under pressure

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Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1874-1881页

作者： CHANG Jing ZHOU XiaoLin ZHAO guoping WANG Li College of Physics and Electronic Engineering Sichuan Normal University

The structural,electronic and elastic properties of solid nitromethane are investigated under pressure by performing first-principles density functional theory(DFT)calculations within the generalized gradient approximation(GGA)and the local density approximation(LDA).The obtained ground state structure properties are found to be consistent with existing experimental and theoretical *** pressure-induced variations of structure parameters(a,b,c and V)indicate that the solid nitromethane has an anisotropic compressibility,and the compression along the c direction is more difficult than along a and b *** the vibration curves of intermolecular bond length and bond angle,we find that the C—N bond is the most sensitive among these bonds under pressure,suggesting that the C—N bonds may be broken first under external *** influence of pressure on the electronic properties of solid NM has been studied,indicating that solid NM is an insulating compound with a large indirect band gap and tends to be a semiconductor with increasing ***,we predict the elastic constants and their pressure dependence for the solid NM with the bulk modulus,Young’s modulus,shear modulus and the Poisson’s ratio derived.

关键词： density functional theory crystal structure electronic structure elastic constants nitromethane

Waterproof,Self‑Adhesive,and Large‑Area Luminescent Perovskite–Polymer Fiber Membranes

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Advanced Fiber Materials 2023年第5期5卷 1737-1748页

作者： Ying Chen Zhenyu Zhang Yanming Sun guoping Wang institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China College of Electronics and information Engineering Shenzhen UniversityShenzhen 518060China

Recently,waterproof lighting and luminescent displays have been achieved in perovskite–polymer composite ***,practical large-area display applications are still limited to the strong electrostatic adhesion(EA)and high *** overcome these deficiencies,large-area(~600 cm2)homogeneous perovskite–polymer fiber membranes(PPFMs)are synthesized by an electrospinning strategy in this *** to the microscopic cladding of the hydrophobic polymer fibers,the electrospun PPFMs exhibit ultrastable underwater luminescence for more than 90 days,and strong EA to diverse materials without pretreatments or additional ***,by utilizing a proposed programmable laser lithography strategy,designed PPFM patterns are fab.icated as the assembly blocks of large-area colorful or tridimensional ***,due to laser thermal ablation effects,the disengaged edges of these blocks are self-stitched with high mechanical stability and *** work provides a simple and effective strategy to realize waterproof,self-adhesive,and large-area display applications of perovskite nanomaterials in real world settings.

关键词： Perovskite-polymer composites Electrospinning Waterproof Large area Pattern displays Laser lithography