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Integrating well logs, 3D seismic, and earthquake data for comprehensive prediction of 3D in-situ stress orientations: A case study from the Weiyuan area in the Sichuan Basin, China

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Petroleum Science 2025年第1期22卷 210-221页

作者： Huan Cao Yang Zhao Hai-Chao Chen le-le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu State Key Laboratory of Petroleum Resources and Engineering and Unconventional Petroleum Research Institute China University of Petroleum (Beijing) Department of Geophysics China University of Petroleum (East China) Aramco Beijing Research Center Aramco Asia

Determining the orientation of in-situ stresses is crucial for various geoscience and engineering applications. Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs) derived from earthquake data and formation micro-imager(FMI) data from well ***, these techniques can be costly, depth-inaccurate, and may lack spatial coverage. To address this issue, we introduce the use of three-dimensional(3D) seismic data(active sources) as a lateral constraint to approximate the 3D stress orientation field. Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy, we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information. We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin, China, a region targeted for shale gas production. By integrating diverse datasets, including 3D seismic, earthquakes, and well logs, we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes). Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax) obtained from FMIs. We analyzed 12earthquakes(magnitude > 3) recorded between 2016 and 2020 for their FMSs and compressional axis(Paxis) orientations. The derived SHmax direction from our 3D stress model is 110°ES(East-South), which shows excellent agreement with the FMSs(within 3.96°). This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations.

关键词： In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager

Emerging progress:photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-le Chen Qiang-Qiang Li Armido Studer Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Organisch-Chemisches Institut Universitat MünsterMunster 48149Germany

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles,nucleophiles,diradicals,and radical acceptors in diverse *** recent years,notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly *** nitroso compounds like nitrosoarenes,acyloxy nitroso compounds,N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to *** this review,we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds,with particular emphasis on their role as bifunctional reagents and acceptors of radicals,carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

维普期刊数据库

Development of ESIPT-based specific fluorescent probes for bioactive species based on the protection-deprotection of the hydroxyl

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Chinese Chemical letters 2025年第2期36卷 49-56页

作者： Haixian Ren Yuting Du Xiaojing Yang Fangjun Huo le Zhang Caixia Yin Department of Chemistry Xinzhou Normal University Research Institute of Applied Chemistry Shanxi University Department of Chemistry The University of Texas at Austin Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Institute of Molecular ScienceShanxi University

Excited-state intramolecular proton-transfer (ESIPT) based fluorescence probes are particularly attractive due to their unique properties including environmental sensitivity, a large Stokes shift, and potential for ratiometric sensing. In general, ESIPT-based fluorophore incorporates an intramolecular hydrogen bonding interaction between a hydrogen bond donor (–OH and NH2are common) and a hydrogen bond acceptor(C=N and C=O). More, protection–deprotection of hydroxyl group as hydrogen bond donor could induce an off-on switch of ESIPT-based emission. Therefore, protection–deprotection of hydroxyl group has been the widely used strategy to design fluorescent probes, where the potential key issue is selecting a protective group that can specifically leave in the presence of the target analyte. In this review, we mainly summarize the specific protecting groups (sites) and deprotection mechanisms for biologically important species (including reactive sulfur species (RSS), reactive oxygen species (ROS), enzymes, etc.), and analyze the advantages and disadvantages of different protection mechanisms from some aspects including probe stability, selectivity, response rate and assay system, etc. Based on the aforementioned, we further point out the current challenges and the potential future direction for developing ESIPT-based probes.

关键词： Bioimaging ESIPT Fluorescence probe Protection-deprotection Specificity

Synthesis of intermetallic PtCo fuel cell catalysts from bimetallic core@shell structured nanoparticles

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Journal of Energy Chemistry 2025年第2期101卷 1-6页

作者： le Zhang lei Tong Shuai Li Chang-Song Ma Kun-Ze Xue Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China

The high activity and stability of intermetallic PtCo nanocatalysts toward oxygen reduction reaction make them a top candidate as low-Pt cathode catalysts in proton exchange membrane fuel cells（PEMFCs）.However,forming intermetallic structures typically requires high-temperature annealing,posing a challenge for achieving well-size control and highly ordered *** we report the design and synthesis of bimetallic co re@shell structured precursors for affording high-performance intermetallic PtCo *** fabrication of the core@shell precursor involves using a molecular ligand containing both sulfur and oxygen donors to selectively bind with Pt colloidal nanoparticles as the core and chelate Co ions as the *** high-temperature annealing,the ligand transforms into carbon coatings around alloy nanoparticles,preventing particle sintering;meanwhile,Co ions in the shell can easily diffuse into the Pt core,which helps to increase the thermodynamic driving force for forming intermetallic *** benefits enable us to obtain the catalyst with finely dispersed nanoparticles（～3.5 nm）and a high ordering degree of 72%.With 0.1 mgPt/cm2cathode loading,the catalyst delivers superior performance and durability in PEMFCs,showing an initial mass activity of 0.56 A/mgPt,an initial power density of 1.05 W/cm2at 0.67 V（H2-air）,and a voltage loss of 26 mV at 0.8 A/cm2after the accelerated durability test.

关键词： Bimetallic structure Fuel cells Intermetallic PtCo Oxygen reduction reaction

Synthesis ofδ-MnO_(2)via ozonation routine for low temperature formaldehyde removal

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Journal of Environmental Sciences 2025年第1期147卷 642-651页

作者： Guijun Fan Yacong Guo Shaohua Chai le Zhang Jian Guan Guojun Ma Ning Han Yunfa Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Science and Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 361021China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Petrochemical Engineering&Environment Zhejiang Ocean UniversityZhoushan 316022China

Nowadays,it is still a challenge to prepared high efficiency and low cost formaldehyde(HCHO)removal catalysts in order to tackle the long-living indoor air ***,δ-MnO_(2)is successfully synthesized by a facile ozonation strategy,where Mn^(2+)is oxidized by ozone(O_(3))bubble in an alkaline *** presents one of the best catalytic properties with a low 100%conversion temperature of 85℃for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr).As a comparison,more than 6 times far longer oxidation time is needed if O3 is replaced by O_(2).Characterizations show that ozonation process generates a different intermediate of tetragonalβ-HMnO_(2),which would favor the quick transformation into the final productδ-MnO_(2),as compared with the relatively more thermodynamically stable monoclinicγ-HMnO_(2)in the O_(2)***,HCHO is found to be decomposed into CO_(2)via formate,dioxymethylene and carbonate species as identified by room temperature insitu diffuse reflectance infrared fourier transform *** these results show great potency of this facile ozonation routine for the highly activeδ-MnO_(2)synthesis in order to remove the HCHO contamination.

关键词： δ-MnO_(2) Ozone oxidation HCHO oxidation In-situ DRIFTS

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI H.GHANDVAR E.JUMAEV S.KHATIR T.CUONG-le School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： double curved beam finite element method functionally graded porous (FGP) material intermediate straight beam O313 vibration analysis

From Imperfection to Perfection: Advanced 3D Facial Reconstruction Using MICA Models and Self-Supervision learning

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Computer Modeling in Engineering & Sciences 2025年第2期142卷 1459-1479页

作者： Thinh D.le Duong Q.Nguyen Phuong D.Nguyen H.Nguyen-Xuan CIRTECH Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Research on reconstructing imperfect faces is a challenging *** this study,we explore a data-driven approach using a pre-trained MICA(MetrIC fAce)model combined with 3D printing to address this *** propose a training strategy that utilizes the pre-trained MICA model and self-supervised learning techniques to improve accuracy and reduce the time needed for 3D facial structure *** results demonstrate high accuracy,evaluated by the geometric loss function and various statistical *** showcase the effectiveness of the approach,we used 3D printing to create a model that covers facial *** findings indicate that our method produces a model that fits well and achieves comprehensive 3D facial *** technique has the potential to aid doctors in treating patients with facial injuries.

关键词： 3D face reconstruction self-supervised learning face defect 3D printed prototypes

Construction of an artificial zinc alloy layer toward stable zinc-metal anode

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Green Energy & Environment 2025年第2期10卷 382-389页

作者： Long Jiang Yizhao Chai Dongdong Ji Liwei Li le Li Bingan Lu Dongmin Li Jiang Zhou State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research InstituteXi'anShaanxi710077China School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South UniversityChangsha410083China School of Physics and Electronics Hunan UniversityChangsha410082China

Aqueous zinc-ion batteries(AZIBs)present a promising option for next-generation batteries given their high safety,eco-friendliness,and resource ***,the practical application of zinc anodes is hindered by inevitable parasitic reactions and dendrite ***,zinc alloy layers(i.e.,ZnCo and ZnFe alloys)were rationally constructed on the zinc surface by chemical displacement *** alloying process exposes more(002)planes of the ZnCo anode to guide the preferential and dendrite-free zinc ***,the ZnCo alloy layer not only effectively inhibits water-induced side reactions but also accelerates electrode kinetics,enabling highly reversible zinc plating/*** a result,the ZnCo anode achieves a Coulombic efficiency of 99.2%over 1300 cycles,and the ZnCo symmetric cell exhibits a long cycle life of over 2000 h at 4.4 mA cm^(-2).Importantly,the ZnCo//NH_(4)V_(4)O_(10)full cell retains a high discharge capacity of 218.4 mAh g^(-1)after 800 ***,the ZnFe-based symmetric cell also displays excellent cycling stability over 2500 h at 1.77 mA cm^(-2).This strategy provides a facile anode modification approach toward high-performance AZIBs.

关键词： Zinc metal anode Zinc alloys Chemical displacement Aqueous zinc-ion batteries

Experimental verification of a PIV-based pressure field reconstruction technology in supersonic flows

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Science China Technological Sciences 2025年第3期68卷 243-261页

作者： Jie TIAN Jinglei XU Shun LIU le CAI College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control of Aeronautics and Astronautics Structures Nanjing University of Aeronautics and Astronautics School of Energy and Power Engineering Jiangsu University

This study proposes a novel approach that involves applying the flux vector splitting(FVS) technique to discretize and approximate conservative Navier-Stokes equations and thus reconstruct pressure fields from planar velocimetry data in compressible flows, especially for supersonic flows with strong shocks. Data are typically resolved by using the particle image velocimetry(PIV) technique. Two supersonic experiments under Mach 2.9–3.0 conditions were conducted to generate strong shocks and investigate the performance of the FVS method, including oblique shock flow and shock wave/boundary layer interaction(SWBLI) coupled with flow separation. Reconstructed pressure fields were comprehensively evaluated. The shock polar results indicated that FVS method possessed higher accuracy in post-shock regions with a pressure ratio error of less than2%, especially for the areas downstream of the shock-shock intersection point and the shock-boundary intersection point, where the conventional Poisson method was ineffective and larger errors accumulated. Wall pressure in SWBLI flow also had better agreement. Furthermore, the performances of different methods were discussed from the perspective of the physical characteristics in supersonic flows, which explained the superiority of the FVS method because the pressure information was delivered along the characteristic direction of physical waves.

关键词： particle image velocimetry supersonic flow pressure reconstruction flux vector splitting technique