检索结果-南通市图书馆

维普期刊数据库

Chronological Study of Coal-seam Water and its Implication on Gas Production in the South Qinshui Basin

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2024年第1期98卷 207-219页

作者： CHEN Biying FANG Lujia lang Yunchao XU Sheng LIU Congqiang ZHANG Luyuan HOU Xiaolin Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Institute of Earth Environments Chinese Academy of SciencesXi’an 710061China

The knowledge of the residence time of formation water is fundamental to understanding the subsurface flow and hydrological *** better identify the origin and evolution of coal seam water and its impact on gas storage and production,this study collected coalbed methane co-produced water in the southeast Qinshui Basin and detected chemical and isotopic compositions,especially 36Cl and 129I *** calculated tracer ages of 129I(5.2–50.6 Ma)and 36Cl(0.13–0.76 Ma)are significantly younger than the age of coal-bearing formation(Pennsylvanian-Cisuralian),indicating freshwater recharge after coal *** model that utilises 129I/I and 36Cl/Cl ratios to constrain the timing of recharge and the proportion of recharge water reveals that over 60%of pre-anthropogenic meteoric water entered coal seams since 10 Ma and mixed with residue initial deposition water,corresponding to the basin inversion in *** spatial distribution of major ion concentrations reveals the primary recharge pathway for meteoric water from coal outcrops at the eastern margin to the basin *** study demonstrates the occurrence of higher gas production rates from wells that accept water recharge in recent times and suggests the possible potential of the non-stagnant zones for high gas production.

关键词： CBM co-produced water iodine-129 chlorine-36 water chemistry Qinshui Basin

维普期刊数据库

Unveiling inverse vulcanized polymers as metal-free,visible-light-driven photocatalysts for cross-coupling reactions

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 142-146页

作者： lang Gao Cen Zhou Rui Wang Feng Lan Bohang An Xiaozhou Huang Xiao Zhang Fujian Key Laboratory of Polymer Science Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical EngineeringCollege of Chemistry and Materials ScienceFujian Normal UniversityFuzhou 350007China Fujian Engineering and Research Center of New Chinese Lacquer Materials College of Materials and Chemical EngineeringMinjiang UniversityFuzhou 350108China

Inverse vulcanized polymers(IVPs) that generated from elemental sulfur and smaller amounts of alkenes have found broad promising applications such as cathode materials for Li-S batteries, dynamic and repairable materials, optics applications, and metal sorption. However, their exploration in organic synthesis is still unprecedented. Here we first report the application of inverse vulcanized polymers in catalysis for organic transformations. A biomass-derived inverse vulcanized polymer(IVP-EAE) is found to be capable of catalyzing cross-coupling reactions in a transition-metal-free fashion under visible *** method allows the direct C–H functionalization of pyrroles and N-arylacrylamides with(hetero)aryl halides, respectively, leading to the formation of two sets of structurally important scaffolds including pyrrole-containing biaryls and 3,3-disubstituted oxindoles with high selectivity. We anticipate this study will not only unveil the new potential of IVPs, but also offer a distinct type of catalysts for organic transformations.

关键词： Cross coupling Inverse vulcanized polymers Metal free Photocatalyst Visible light

维普期刊数据库

Comparative Analysis of ARIMA and LSTM Model-Based Anomaly Detection for Unannotated Structural Health Monitoring Data in an Immersed Tunnel

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第5期139卷 1797-1827页

作者： Qing Ai Hao Tian Hui Wang Qing lang Xingchun Huang Xinghong Jiang Qiang Jing School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Key Laboratory of Road and Bridge Detection and Maintenance Technology of Zhejiang Province Hangzhou311305China Zhejiang Scientific Research Institute of Transport Hangzhou310023China State Key Laboratory of Coal Mine Dynamics and Control Chongqing UniversityChongqing400044China Hong Kong-Zhuhai-Macao Bridge Authority Zhuhai519060China

Structural Health Monitoring(SHM)systems have become a crucial tool for the operational management of long *** immersed tunnels exposed to both traffic loads and the effects of the marine environment,efficiently identifying abnormal conditions from the extensive unannotated SHM data presents a significant *** study proposed amodel-based approach for anomaly detection and conducted validation and comparative analysis of two distinct temporal predictive models using SHM data from a real immersed ***,a dynamic predictive model-based anomaly detectionmethod is proposed,which utilizes a rolling time window for modeling to achieve dynamic *** the assumption of temporal data similarity,an interval prediction value deviation was employed to determine the abnormality of the ***,dynamic predictive models were constructed based on the Autoregressive Integrated Moving Average(ARIMA)and Long Short-Term Memory(LSTM)*** hyperparameters of these models were optimized and selected using monitoring data from the immersed tunnel,yielding viable static and dynamic predictive ***,the models were applied within the same segment of SHM data,to validate the effectiveness of the anomaly detection approach based on dynamic predictive modeling.A detailed comparative analysis discusses the discrepancies in temporal anomaly detection between the ARIMA-and LSTM-based *** results demonstrated that the dynamic predictive modelbased anomaly detection approach was effective for dealing with unannotated SHM *** a comparison between ARIMA and LSTM,it was found that ARIMA demonstrated higher modeling efficiency,rendering it suitable for short-term *** contrast,the LSTM model exhibited greater capacity to capture long-term performance trends and enhanced early warning capabilities,thereby resulting in superior overall performance.

关键词： Anomaly detection dynamic predictive model structural health monitoring immersed tunnel LSTM ARIMA

Displacement characteristics of CO_(2)flooding in extra-high water-cut reservoirs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Geoscience 2024年第1期5卷 212-218页

作者： Rui Wang Yaxiong Zhang Chengyuan Lyu Zengmin Lun Maolei Cui Dongjiang lang SINOPEC Petroleum Exploration and Production Research Institute BeijingChina

Carbon dioxide(CO_(2))flooding is a widely applied recovery method during the tertiary recovery of oil and gas.A high water saturation condition in reservoirs could induce a‘water shielding’phenomenon after the injection of CO_(2).This would prevent contact between the injected gas and the residual oil,restricting the development of the miscible zone.A micro-visual experiment of dead-end models,used to observe the effect of a film of water on the miscibility process,indicates that CO_(2)can penetrate the water film and come into contact with the residual oil,although the mixing is significantly ***,the dissolution loss of CO_(2)at high water-cut conditions is not *** oil-water partition coefficient,defined as the ratio of CO_(2)solubility in an oil-brine/two-phase system,keeps constant for specific reservoir conditions and changes little with an injection *** NMR device shows that when CO_(2)flooding follows water flooding,the residual oil decreasesdnot only in medium and large pores but also in small and micro *** levels of higher water saturation,CO_(2)displacement is characterized initially by a low oil production rate and high *** the CO_(2)breakthrough,the water-cut decreases sharply and the oil production rate increases *** response time of CO_(2)flooding at high watercut reservoirs is typically delayed and *** results were confirmed in a pilot test for CO_(2)flooding at the P1-1 well group of the Pucheng *** from this pilot study also suggest that a larger injection gas pore volume available for CO_(2)injection is required to offset the dissolution loss in high water saturation conditions.

关键词： Displacement characteristics CO_(2)flooding Water shield phenomenon Oil-water partition coefficient Response time High water-cut

Multiplicative forms on Poisson groupoids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2024年

作者： Zhuo Chen Honglei lang Zhangju Liu Department of Mathematical Sciences Tsinghua University College of Science China Agricultural University School of Mathematics and Statistics Henan University

First, we prove a decomposition formula for any multiplicative differential form on a Lie groupoid G. Next, we prove that if G is a Poisson Lie groupoid, then the space Ω·mult(G) of multiplicative forms on G has a differential graded Lie algebra(DGLA) structure. Furthermore, when combined with Ω·(M), which is the space of forms on the base manifold M of G, Ω·mult(G) forms a canonical DGLA crossed module. This supplements a previously known fact that multiplicative multi-vector fields on G form a DGLA crossed module with the Schouten algebra Γ(∧·A) stemming from the Lie algebroid A of G.

关键词：

Re-quantization based binary graph neural networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第7期67卷 160-171页

作者： Kai-lang YAO Wu-Jun LI National Key Laboratory for Novel Software Technology Department of Computer Science and TechnologyNanjing University

Binary neural networks have become a promising research topic due to their advantages of fast inference speed and low energy consumption. However, most existing studies focus on binary convolutional neural networks, while less attention has been paid to binary graph neural networks. A common drawback of existing studies on binary graph neural networks is that they still include lots of inefficient full-precision operations in multiplying three matrices and are therefore not efficient enough. In this paper, we propose a novel method, called re-quantization-based binary graph neural networks(RQBGN), for binarizing graph neural networks. Specifically, re-quantization, a necessary procedure contributing to the further reduction of superfluous inefficient full-precision operations, quantizes the results of multiplication between any two matrices during the process of multiplying three matrices. To address the challenges introduced by requantization, in RQBGN we first study the impact of different computation orders to find an effective one and then introduce a mixture of experts to increase the model capacity. Experiments on five benchmark datasets show that performing re-quantization in different computation orders significantly impacts the performance of binary graph neural network models, and RQBGN can outperform other baselines to achieve state-of-the-art performance.

关键词： graph neural networks binary neural networks mixture of experts computation-efficient algorithms

同方期刊数据库

Coupling effect of cement-stabilization and biopolymer-modification on the mechanical behavior of dredged sediment

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3284-3298页

作者： Lei lang Jiangshan Li Xiao Huang Ping Wang Wei Zhang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Hubei Provincial Key Laboratory of Contaminated Sludge and Soil Science and Engineering Wuhan430071China University of Chinese Academy of Sciences Beijing100049China

Nowadays,biopolymer stabilization as a promising eco-friendly approach in soft ground improvement has attracted wide ***,the feasibility of using biopolymer as a green additive of cementstabilized dredged sediment(CDS)with high water content is still *** this study,guar gum(GG)and xanthan gum(XG)were adopted as typical biopolymers,and a series of unconfined compressive strength(UCS),splitting tensile strength(STS)and scanning electron microscopy(SEM)tests were performed to evaluate the mechanical and microstructural properties of XG-and GG-modified CDSs considering several factors including biopolymer modification,binderesoil ratio and wateresolid ***,the micro-mechanisms revealing the evolutions of mechanical properties of biopolymermodified CDS were *** results indicate that the addition of XG can effectively improve the strength of CDS,while the GG has a side *** XG content of 9%was recommended,which can improve the 7 d-and 28 d-UCSs by 196%and 51.8%,together with the 7 d-and 28 d-STSs by 118.3%and 42.2%,*** the binderesoil ratio or decreasing the wateresolid ratio significantly improved the strength gaining but aggravated the brittleness characteristics of *** XG to CDS contributed to the formation of microstructure with more compactness and higher cementation degrees of ordinary Portland cement(OPC)-XG-stabilized DS(CXDS).The micro-mechanism models revealing the interactions of multiple media including OPC cementation,biopolymer film bonding and bridging effects inside CXDS were *** key findings confirm the feasibility of XG modification as a green and high-efficiency mean for improving the mechanical properties of CDS.

关键词： Dredged sediment(DS) Stabilization Biopolymer modification Mechanical properties Micro-mechanism

Interfacial mechanism of hydrogel with controllable thickness for stable drag reduction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第2期12卷 231-244页

作者： Xiaotong WU Ying LIU Yunlei ZHANG Xingwei WANG Wufang YANG lang JIANG Shuanhong MA Meirong CAI Feng ZHOU School of Advanced Manufacturing Nanchang UniversityNanchang 330031China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Shandong Laboratory of Yantai Advanced Materials and Green ManufactureYantai 264006China

Surface wettability plays a significant role in reducing solid–liquid frictional resistance,especially the superhydrophilic/hydrophilic interface because of its excellent thermodynamic *** this work,poly(acrylic acid)-poly(acrylamide)(PAA–PAM)hydrogel coatings with different thicknesses were prepared in situ by polydopamine(PDA)-UV assisted surface catalytically initiated radical *** drag reduction performance of hydrogel surface was measured using a rotational rheometer by the plate–plate *** experimental results showed that the average drag reduction of hydrogel surface could reach up to about 56%in Couette flow,which was mainly due to the interfacial polymerization phenomenon that enhanced the ability of hydration layer to delay the momentum dissipation between fluid layers and the diffusion behavior of *** proposed drag reduction mechanism of hydrogel surface was expected to shed new light on hydrogel–liquid interface interaction and provide a new way for the development of steady-state drag reduction methods.

关键词： steady state drag reduction hydrogel interface hydration hydrophilic

Conversion of magnetron-sputtered sacrificial intermediate layer into a stable FeCo-LDH catalyst for oxygen evolution reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4307-4313页

作者： Zhiquan lang Guang-Ling Song Xingpeng Liao Wenzhong Huang Yixing Zhu Haipeng Wang Dajiang Zheng Center for Marine Materials Corrosion and Protection College of MaterialsXiamen UniversityXiamen 361005China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China The University of Queensland St.LuciaOLD 4072Australia State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Controllable and scalable preparation of electrocatalyst materials holds significant importance for their practical *** sputtering is a highly effective synthesis method,known for its producing uniform films and allowing easy control of component *** this paper,we propose an in-situ synthesis method for layered double hydroxide(LDH)electrocatalysts through sacrificing magnetron sputtered *** resulting FeCo-LDH catalyst demonstrated a low overpotential of only 300 mV at 10 mA·cm^(-2).Furthermore,we conducted spectroscopic analysis to investigate the surface changes of the catalysts during the oxygen evolution reaction(OER)*** findings indicated that the formation of Co oxyhydroxides plays a beneficial role in enhancing the catalytical performance of the FeCo-LDH for OER *** restructuring strategy of converting a magnetron-sputtered sacrificial film into a catalytical LDH introduces a new avenue to the synthesis of transition metal-based electrocatalysts.

关键词： magnetron co-sputtering surface reconstruction electrocatalyst oxygen evolution reaction