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Full waveform inversion based on hybrid gradient

Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang qin Jian-Hua Wang Peng Song Heng-Guang Shen Sheng-qi Yu Ben-Jun Ma xue-qin Liu qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

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C(sp^(3))-H bond functionalization of oximes derivatives via 1,5-hydrogen atom transfer induced by iminyl radical

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Chinese Chemical Letters 2022年第3期33卷 1199-1206页

作者： Dao-qing Dong Jing-Cheng Song Shao-Hui Yang qi-xue qin Zu-Li Wang En-Xuan Zhang Yuan-Yuan Sun qing-qing Han Shan Yue College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdao 266109China Asymchem Life Science(Tianjin)Co. Ltd.Tianjin 300457China

Oximes derivatives have been vastly used in organic synthesis. In this review, C(sp^(3))-H bond functionalization of oximes derivatives via iminyl radical induced 1,5-hydrogen atom transfer was discussed. According to the different type of products, this review was divided into three parts: (1) C(sp^(3))-H bond functionalization for C-C bond formation. (2) C(sp^(3))-H bond functionalization for C-N bond formation. (3) C(sp^(3))-H bond functionalization for C-S, C-F bond formation.

关键词： Oximes derivatives 1 5-hydrogen atom transfer Iminyl radicals C(sp^(3))-H Bond Visible light

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Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： xue-qin Li Lu-Kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

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An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： qi Liu xue-Dong Li Liang Cheng Li Liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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Tendencies of alloyed engineering in BiOX-based photocatalysts:a state-of-the-art review

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Rare Metals 2024年第4期43卷 1488-1512页

作者： Yan-Dong Sun Chao Zeng xue Zhang Zi-qi Zhang Bo Yang Sheng-qi Guo Tianjin Key Laboratory of Clean Energy and Pollutant Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Institute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation School of Physics and Electronic InformationAnhui Province Industrial Generic Technology Research Center for Alumics MaterialsHuaibei Normal UniversityHuaibei235000China

Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental *** to the unique layer-like structure,BiOX(Cl,Br,I)is frequently used in ***,inherent flaws in BiOX,such as an inappropriate band gap and low carrier separation efficiency,restrict its capacity for *** to the tunable grouping layer,alloying engineering is employed to optimize the intrinsic properties of BiOX and alloyed BiOX becomes a promising photocatalytic *** review describes the structure of BiOX,where tunable halogen layers provide favorable conditions for the implementation of alloying engineering to improve intrinsic *** article compares the effects and mechanisms of alloying engineering on the optimization of the energy band structure and carrier behavior of BiOX,and lists various modification methods used to improve the optimization of the intrinsic properties by alloying engineering,including defect engineering,morphology control as well as the synergy between alloying and other modification methods(bismuth-rich strategies,cation doping,construction of heterojunctions and plasma resonance effects).Subsequently,applications of alloyed BiOX in energy and environmental fields are summarized,including contaminant degradation,antibacterial,CO_(2)reduction,nitrogen fixation and organic ***,we summarize the current challenges and future directions of alloyed *** is expected that this work will provide guidance and assistance for an in-depth study and understanding of the mechanisms of alloying engineering to optimize intrinsic properties and design alloyed BiOX with higher photocatalytic activity.

关键词： Bismuth oxyhalide Photocatalytic Alloyed engineering Microstructural regulation Application

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Intensified warming suppressed the snowmelt in the Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 452-463页

作者： Xiang LI Peng CUI xue-qin ZHANG Fang ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China‒Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on ***,these connections are often overlooked,leading to an unclear relationship between temperature and *** study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme *** a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme *** annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow *** contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or *** direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt ***,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt *** also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt *** study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological *** findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关键词： Climate change Extreme temperature Snowmelt Structural equation model Tibetan Plateau

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Improving Diversity with Multi-Loss Adversarial Training in Personalized News Recommendation

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Computers, Materials & Continua 2024年第8期80卷 3107-3122页

作者： Ruijin xue Shuang Feng qi Wang School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

Users’interests are often diverse and multi-grained,with their underlying intents even more *** captur-ing users’interests and uncovering the relationships between diverse interests are key to news ***,diversity is an important metric for evaluating news recommendation algorithms,as users tend to reject excessive homogeneous information in their recommendation ***,recommendation models themselves lack diversity awareness,making it challenging to achieve a good balance between the accuracy and diversity of news *** this paper,we propose a news recommendation algorithm that achieves good performance in both accuracy and *** most existing works that solely optimize accuracy or employ more features to meet diversity,the proposed algorithm leverages the diversity-aware capability of the ***,we introduce an augmented user model to fully capture user intent and the behavioral guidance they might undergo as a ***,we focus on the relationship between the original clicked news and the augmented clicked ***,we propose an effective adversarial training method for diversity(AT4D),which is a pluggable component that can enhance both the accuracy and diversity of news recommendation *** experiments on real-world datasets confirm the efficacy of the proposed algorithm in improving both the accuracy and diversity of news recommendations.

关键词： News recommendation diversity accuracy data augmentation

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Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： qi Meng Tao qin Huanran Miao Ge Zhang qian Zhang Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

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Drosophila X virus-like particles as delivery carriers for improved oral insecticidal efficacy of scorpion Androctonus australis peptide against the invasive fruit fly,Drosophila suzukii

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Insect Science 2024年第3期31卷 847-858页

作者： qi xue Luc Swevers Clauvis Nji Tizi Taning Faculty of Bioscience Engineering Department of Plants and CropsGhent UniversityGhentBelgium Insect Molecular Genetics and Biotechnology Institute of Biosciences and ApplicationsNational Centre for Scientific Research"Demokritos"AthensGreece

Insect-specific neurotoxic peptides derived from the venoms of scorpions and spiders can cause acute paralysis and death when injected into insects,offering a promising insecticidal component for insect pest ***,effective delivery systems are required to help neurotoxic peptides pass through the gut barrier into the hemolymph,where they can ***,we investigated the potential of a novel nanocarrier,Drosophila X virus-like particle(DXV-VLP),for delivering a neurotoxin from the scorpion Androctonus australis Hector(AaIT)against the invasive pest fruit fly,Drosophila *** results show that the fusion proteins of DXV polyproteins with AalT peptide at their Ctermini could be sufficiently produced in Lepidoptera Hi5 cells in a soluble form using the recombinant baculovirus expression system,and could self-assemble into VLPs with similar particle morphology and size to authentic DXV *** addition,the AalT peptides displayed on DXV-VLPs retained their toxicity,as demonstrated in injection bioassays that resulted in severe mortality(72%)in adults after 72 *** fed to adults,mild mortality was observed in the group treated with DXV-AalT(38%),while no mortality occurred in the group treated with AaIT peptide,thus indicating the significant role of DXV-VLPs in delivering AalT ***,this proof-of-concept study demonstrates for the first time that VLPs can be exploited to enhance oral delivery of insect-specific neurotoxic peptides in the context of pest ***,it provides insights for further improvements and potentially the development of neurotoxin-based bioinsecticides and/or transgenic crops for insect pest control.

关键词： AalT Drosophila suzuki nanocarrier neurotoxic peptides pest control virus-like particle(VLP)

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The regulatory mechanism of rapid lignification for timely anther dehiscence

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Journal of Integrative Plant Biology 2024年第8期66卷 1788-1800页

作者： Jing-Shi xue Yi-Feng Feng Ming-qi Zhang qin-Lin Xu Ya-Min Xu Jun-qin Shi Li-Fang Liu Xiao-Feng Wu Shui Wang Zhong-Nan Yang Shanghai Key Laboratory of Plant Molecular Sciences College of Life SciencesShanghai Normal UniversityShanghai 200234China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China Development Center of Plant Germplasm Resources College of Life SciencesShanghai Normal UniversityShanghai 200234China

Anther dehiscence is a crucial event in plant reproduction,tightly regulated and dependent on the lignification of the anther *** this study,we investigated the rapid lignification process that ensures timely anther dehiscence in *** findings reveal that endothecium lignification can be divided into two distinct *** Phase Ⅰ,lignin precursors are synthesized without polymerization,while Phase Ⅱ involves simultaneous synthesis of lignin precursors and *** transcription factors MYB26,NST1/2,and ARF17 specifically regulate the pathway responsible for the synthesis and polymerization of lignin monomers in Phase Ⅱ.MYB26-NST1/2 is the key regulatory pathway responsible for endothecium lignification,while ARF17 facilitates this process by interacting with ***,our results demonstrate that the lignification of the endothecium,which occurs within approximately 26 h,is much faster than that of the vascular *** findings provide valuable insights into the regulation mechanism of rapid lignification in the endothecium,which enables timely anther dehiscence and successful pollen release during plant reproduction.

关键词： anther dehiscence ARF17 endothecium lignin MYB26 NST

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