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Automatic velocity picking based on optimal key points tracking algorithm

Petroleum Science 2024年第2期21卷 903-917页

作者： Yong-Hao Wang wen-Kai lu Song-Bai Jin Yang li Yu-Xuan li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

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Pt nanoclusters modified porous g-C_(3)N_(4)nanosheets to significantly enhance hydrogen production by photocatalytic water reforming of methanol

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Chinese Journal of Chemical Engineering 2024年第2期66卷 40-50页

作者： Yi-Fei liang Jin-Rong lu Shang-Kun Tian wen-Quan Cui li liu Hebei Provincial Key Laboratory of Environmental Photocatalytic and Electrocatalytic Materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshan 063210China

For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild *** attention has been paid to gC_(3)N_(4)as a promising photocatalyst for the generation of *** improve the separation of photogenerated charge,porous nanosheet g-C_(3)N_(4)was modified with Pt nanoclusters(Pt/g-C_(3)N_(4))through impregnation and following photo-induced *** catalyst showed excellent photocatalytic activity of water reforming of methanol fo r hydrogen production with a 17.12 mmol·g^(-1)·h^(-1)rate at room temperature,which was 311 times higher than that of the unmodified g-C_(3)N_(4).The strong interactions of Pt-N in Pt/g-C_(3)N_(4)constructed effective electron transfer channels to promote the separation of photogenerated electrons and holes *** addition,in-situ infrared spectroscopy was used to investigate the intermediates of the hydrogen production reaction,which proved that methanol and water eventually turn into H_(2)and CO_(2)via formaldehyde and *** study provides insights for understanding the photocatalytic hydrogen production in the water reforming of methanol.

关键词： Water reforming of methanol Photocatalysis g-C_(3)N_(4) Pt nanoclusters Hydrogen production

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Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary Center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian Long Zhiwu lu Xiao-lin li Peng Xue wen-Bo liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

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M^(6)A modification in cardiovascular disease:With a focus on programmed cell death

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Genes & Diseases 2024年第5期11卷 272-284页

作者： wen li Yao liu Ruiyan Xu Yuan Zong lu He Jun Hu Guohua li Institute of Cardiovascular Disease Key Laboratory for Arteriosclerology of Hunan ProvinceHunan International Scientific and Technological Cooperation Base of Arteriosclerotic DiseaseDepartment of PathophysiologyMOE Key Lab of Rare Pediatric DiseasesHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Cardiovascular Medicine The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Obstetrics and Gynecology The First Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Cardiovascular Surgery The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

N^(6)-methyladenosine(m^(6)A)methylation is one of the most predominant internal RNA modifications in eukaryotes and has become a hot spot in the field of epigenetics in recent *** diseases(CVDs)are a leading cause of death *** evidence demonstrates that RNA modifications,such as the m^(6)A modification,are associated with the development and progression of many diseases,including *** increasing body of studies has indicated that programmed cell death(PCD)plays a vital role in ***,the molecular mechanisms underlying m^(6)A modification and PCD in CVDs remain poorly ***,elaborating on the highly complex connections between the m^(6)A mechanisms and different PCD signaling pathways and clarifying the exact molecular mechanism of m^(6)A modification mediating PCD have significant meaning in developing new strategies for the prevention and therapy of *** is great potential for clinical application.

关键词： Apoptosis Autophagy Cardiovascular diseases Ferroptosis N^(6)-methyladenosine Programmed cell death Pyroptosis

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Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen Xiaoyu wen Bingcheng li Jian lu Zile li Feng Feng Qingtao Wang Qunfeng Zhang Xiaonian li State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

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Tmem39b promotes tumor progression and sorafenib resistance by inhibiting ferroptosis in hepatocellular carcinoma

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Oncology Research 2024年第8期32卷 1347-1357页

作者： MING ZHUANG XUE ZHANG lu li liMING wen JIAMIN QIN Department of Gastroenterology Sichuan Mianyang 404 HospitalMianyang621000China

Hepatocellular carcinoma(HCC)poses a signiﬁcant threat to human *** to sorafenib in the chemotherapy of HCC is a common and signiﬁcant issue that profoundly impacts clinical *** several members of the transmembrane(TMEM)protein family have been implicated in the occurrence and progression of HCC,the association between TMEM39b and HCC remains *** study revealed a signiﬁcant overexpression of TMEM39b in HCC,which correlated with a poor *** investigation revealed that RAS-selective lethal 3(RSL3)induced pronounced ferroptosis in HCC,and knocking down the expression of TMEM39b signiﬁcantly decreased its ***,following the induction of ferroptosis in HCC by sorafenib,knocking down the expression of TMEM39b also decreased the severity of ferroptosis,enhancing HCC tolerance to *** conclusion,we propose that TMEM39b promotes tumor progression and resistance to sorafenib by inhibiting ferroptosis in HCC.

关键词： TMEM39b Sorafenib Ferroptosis Hepatocellular carcinoma

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Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo li Feng Jiang Zhengyi Jiang Zige Tian Tian Qiu Tao Zhang Qiuling wen Xizhao lu Jing lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

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Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li.wen lu Hui luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

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Efficient and fair PPO-based integrated scheduling method for multiple tasks of SATech-01 satellite

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Chinese Journal of Aeronautics 2024年第2期37卷 417-430页

作者： Qi SHI lu li Ziruo FANG Xingzi BI Huaqiu liU Xiaofeng ZHANG wen CHEN Jinpei YU Shanghai Satellite Network Research Institute CO. LTDShanghai 201210China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201306China University of Chinese Academy of Sciences Beijing 100039China

SATech-01 is an experimental satellite for space science exploration and on-orbit demonstration of advanced *** satellite is equipped with 16 experimental payloads and supports multiple working modes to meet the observation requirements of various *** to the limitation of platform power supply and data storage systems,proposing reasonable mission planning schemes to improve scientific revenue of the payloads becomes a critical *** this article,we formulate the integrated task scheduling of SATech-01 as a multi-objective optimization problem and propose a novel Fair Integrated Scheduling with Proximal Policy Optimization(FIS-PPO)algorithm to solve *** use multiple decision heads to generate decisions for each task and design the action mask to ensure the schedule meeting the platform *** results show that FIS-PPO could push the capability of the platform to the limit and improve the overall observation efficiency by 31.5%compared to rule-based plans currently ***,fairness is considered in the reward design and our method achieves much better performance in terms of equal task *** of its low computational complexity,our task scheduling algorithm has the potential to be directly deployed on board for real-time task scheduling in future space projects.

关键词： Satellite observatories SATech-01 Multi-modes platform Scheduling algorithms Reinforcement learning Proximal Policy Optimization(PPO)

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Multi-Scale Pore Structure Heterogeneity in Tuff Reservoirs Investigated with Multi-Experimental Method and Fractal Dimensions in Chang 7 Formation,Southern Ordos Basin

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Journal of Earth Science 2024年第2期35卷 666-686页

作者： Hao lu Qing li Dali Yue Dongdong Xia Shenghe Wu Lang wen Yu He State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China Petroleum Exploration and Development Institute of SINOPEC Beijing100083China

The tight tuff reservoir is an unusual type of unconventional reservoir with strong ***,there is a lack of research on the microscopic pore structure that causes the heterogeneity of tuff *** the Chang 7 Formation in Ordos Basin,China as a case study,carbon-dioxide gas adsorption,nitrogen gas adsorption and high-pressure mercury injection are integrated to investigate the multi-scale pore structure characteristics of tuff ***,the fractal dimension is introduced to characterize the complexity of pore structure in tuff *** this multi-experimental method,the quantitative characterizations of the full-range pore size distribution of four tuff types were obtained and compared in the size ranges of micropores,mesopores and *** dimension curves derived from full-range pores are divided into six segments as D1,D2,D3,D4,D5 and D6 corresponding to fractal characteristics of micropores,smaller mesopores,larger mesopores,smaller macropores,medium macropores and larger macropores,*** macropore volume,average macropore radius and fractal dimension D5 significantly control petrophysical *** larger macropore volume,average macropore radius and D5 correspond to favorable pore structure and good reservoir quality,which provides new indexes for the tuff reservoir *** study enriches the understanding of the heterogeneity of pore structures and contributes to unconventional oil and gas exploration and development.

关键词： tuff reservoir pore structure carbon-dioxide gas adsorption nitrogen gas adsorption high-pressure mercury injection fractal dimension petroleum geology

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