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The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG Weidong SUN xing ding Yusheng zhao Yibing LI Xiuqi SHANG CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured H_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Numerical evaluations on the fluid production in the in-situ conversion of continental shale oil reservoirs

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Petroleum Science 2024年第04期21卷 2485-2501页

作者： zhao-Bin Zhang Maryelin Josefina Brice?o Montilla Shou-ding Li Xiao Li Jian-Peng xing Yan-Zhi Hu Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Earth Sciences Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Institute of Energy Peking University

In-situ conversion presents a promising technique for exploiting continental oil shale formations,characterized by highly fractured organic-rich rock. A 3D in-situ conversion model, which incorporates a discrete fracture network, is developed using a self-developed thermal-flow-chemical(TFC) *** of the model elucidates the in-situ conversion process in three stages and defines the transformation of fluids into three distinct outcomes according to their end stages. The findings indicate that kerogen decomposition increases fluid pressure, activating fractures and subsequently enhancing permeability. A comprehensive analysis of activated fracture permeability and heating power reveals four distinct production modes, highlighting that increasing heating power correlates with higher cumulative fluid production. Activated fractures, with heightened permeability, facilitate the mobility of heavy oil toward production wells but hinder its cracking, thereby limiting light hydrocarbon ***, energy efficiency research demonstrates the feasibility of the in-situ conversion in terms of energy utilization, especially when considering the surplus energy from high-fluctuation energy sources such as wind and solar power to provide heating.

关键词： In-situ conversion Continental shale oil Natural fracture network TFC model

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng Liu Zhen-xing xing Gong-jin Cheng Xue-yong ding Xiang-xin Xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Porous Structures and Short-Wavelength Photoluminescence of C^(+)-Implanted SiO_(2) Films

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Chinese Physics Letters 1999年第5期16卷 361-363页

作者： zhao Jun MAO Dong-sheng ding xing-zhao LIN Zi-xin JIANG Bing-yao YU Yue-hui YANG Gen-qing LIU Xiang-huai S.Jin H.Bender Ion Beam Laboratory Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 State Key Laboratory of Transducer Technology Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050 IMEC KapeldreefB-3001LeuvenBelgium

C ions of three different energies were sequentially implanted into SiO_(2) films grown by plasma enhanced chemical vapor *** of the samples were studied with transmission electron microscopy(TEM)and secondary ion mass spectroscopy As revealed by cross-sectional TEM,porous structures had been created in the implanted region during ion *** photoluminescence(PL)was detected from the as-implanted ***,intense short-wavelength PL peaking at 360-370nm and ~450nm was observed from the annealed *** blue light from samples excited by an Xe lamp can be observed by naked eyes at room *** light emission mechanisms are briefly discussed.

关键词： temperature. deposition. sectional

Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： You zhao xing He Mingliang Zhou Tingwen Huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence *** previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization *** this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual *** satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence *** only requires assuming convexity of the objective *** validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.

Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

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Science China Chemistry 2024年第2期67卷 632-641页

作者： xing Liu Jianjun Zhou Shumei Liu Jianqing zhao School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Key Lab Guangdong High Property&Functional Polymer Materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical *** this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent *** latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were *** thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and ***,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,Young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP *** work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance

A viscoelastic metamaterial beam for integrated vibration isolation and energy harvesting

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1243-1260页

作者： Long zhao Zeqi LU Hu ding Liqun CHEN Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China School of Microelectronics Shanghai UniversityShanghai201800China

Locally resonant metamaterials have low-frequency band gaps and the capability of converging vibratory energy in the band gaps at resonant *** has been demonstrated by several researchers that the dissipatioin of vibratory energy within the band gap can be improved by using viscoelastic *** paper designs an integrated viscoelastic metamaterial for energy harvesting and vibration *** viscoelastic metamaterial is achieved by a viscoelastic beam periodically arrayed with spatial ball-pendulum nonlinear energy *** nonlinear resonator with an energy harvesting function is achieved by placing a free-rolling magnetic ball in a spherical cavity with an additional induction *** dynamic equations of viscoelastic metamaterials under transverse excitation are established,and the energy harvesting and vibration isolation characteristics within the dispersion relation of viscoelastic metamaterials are *** results show that the vibrations of the main body of the viscoelastic metamaterial beam are significantly suppressed in the frequency range of the local resonance band *** the same time,the elastic waves are limited in the nonlinear resonator with an energy harvesting function,which improves the energy ***,an experimental platform of viscoelastic metamaterial vibration is established for validation purposes.

关键词： viscoelastic metamaterial nonlinear vibration vibration isolation energy harvesting

Stable watt-level mode-locked noise-like pulse from an all-PM fiber oscillator at 2 μm

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Chinese Optics Letters 2024年第6期22卷 154-157页

作者： Meng Wang Junjia ding Deqin Ouyang Yewang Chen Junqing zhao xing Liu Shuangchen Ruan Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes Sino-German College of Intelligent ManufacturingShenzhen Technology UniversityShenzhen 518118China

We have experimentally presented a watt-level noise-like (NL) pulse mode-locked all-polarization-maintaining(PM) fiber laser centered at ~1995 nm, which can directly generate stable NL pulses with a maximum output power of ~1.017 W and pulse energy of ~0.61 μJ, representing the highest output power of mode-locked NL pulse at 2 μm from any fiber oscillators,to the best of our knowledge. The mode-locked NL pulse laser exhibits an excellent stability with a power fluctuation of~0.1% in 8 h of monitoring, and a signal-to-noise ratio of ~83 dB at a fundamental frequency of ~1.662 MHz. Moreover, the pulse envelope and coherence spike width of the NL pulse can be widely tuned from ~4.5 ns to ~16 ns, and ~364 fs to~323 fs, respectively, with the enhancement of the pump power. Such an all-PM fiber oscillator is the ideal seed source for the implementation of a high-power NL pulse laser and has potential valuable applications in mid-infrared spectroscopy and industrial processing.

关键词： Tm-doped fiber laser mode locking noise-like pulse