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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability

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Petroleum Science 2024年第2期21卷 1113-1121页

作者： Ming-Wei Zhao Zhen-Feng Ma Cai-Li dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-long Cheng xiang-Yu Wang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao266580ShandongChina Sinopec Shengli Oilfield Dongying257001ShandongChina Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada East China Petroleum Bureau of Sinopec Nanjing210011JiangsuChina

Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction ***,their performance is severely affected at high *** reducing agent is the key to determine the drag reducing performance of *** this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant *** slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and *** contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ***,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing ***,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications.

关键词： Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance

PARP1-DNA co-condensation:the driver of broken DNA repair

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2351-2353页

作者： xiang Wei Fangfang Zhou long Zhang Life Sciences Institute The Second Affiliated Hospital of the Zhejiang University School of MedicineThe MOE Key Laboratory of Biosystems Homeostasis&Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell BiologyZhejiang UniversityHangzhouChina The First Affiliated Hospital the Institutes of Biology and Medical SciencesSuzhou Medical CollegeSoochow UniversitySuzhouJiangsu 215123China

A recent study published by Simon Alberti1 in Cell has revealed that DNA double-strand break(DSB)sites that prevent the disjunction of broken DNA ends are formed through poly(ADPribose)(PAR)polymerase 1(PARP1)-DNA co-condensation.1(Fig.1).Here,a comprehensive and novel model was provided for the ordered assembly of PARP1-DNA condensates,which can rationally make clear broken DNA end synapses and how repair effectors are recruited to repair DSB.

关键词： PARP1 repair rational

Unraveling the mysteries of volatile cycling and habitability on Earth and beyond

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National Science Review 2024年第6期11卷 8-9页

作者： Yi-Gang Xu Ri-xiang Zhu Min-Han dai State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences State Key Laboratory of Lithosphere Evolution Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Marine Environmental Science Xiamen University

The origin and cycling of volatiles, including water, carbon dioxide, and nitrogen, are fundamental to the very existence of habitable planets. These volatile compounds, often taken for granted,are the lifeblood of planetary systems, influencing almost everything from atmospheric composition and climate regulation to deep Earth processes and the emergence of life.

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Insight of enriched basalts into the nature and evolution of mantle lithosphere beneath craton margins

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Science China Earth Sciences 2024年第10期67卷 3128-3142页

作者： Hong-Kun dai Jianping ZHENG Qing XIONG Linlin HU xiang ZHOU State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China

Refractory lithospheric deep roots are the cornerstone for the prolonged stability of cratons and mantle xenoliths are normally the key targets for study on the evolution of such deep roots. In regions with few mantle xenoliths, the basalts enriched in radiogenic isotopic compositions due to marked lithospheric mantle contribution are crucial to unmask the lithospheric mantle evolution based on a comprehensive study involving petrology, geochemistry and thermodynamic modelling. Here, the Early Cretaceous basalts from the northwest North China Craton with few mantle xenoliths are taken as an example to show the significance of enriched basalts on the study of lithospheric mantle. These basalts are characterized by high silica and alkali contents(SiO_(2)=45.8–59.8 wt.%, K_(2)O+Na_(2)O=4.81–9.88 wt.%), arc-type trace-element patterns and enriched radiogenic isotope compositions(e.g., ε_(Nd)=-2.64–-12.88,^(87)Sr/^(86)Sr=0.7063–0.7093). The TiO_(2) and FeO(total) contents are higher than those of natural and experimental melts from refractory mantle peridotite but comparable to those of partial melts of fertile mantle *** high contents of fluid-loving elements(e.g., Rb and Ba) suggest source metasomatism by aqueous fluids. Combined with thermodynamic modelling and regional tectonic history, these enriched basalts likely record simultaneous decompression melting of asthenosphere and low-extent melting of thin and fertile lithospheric mantle fluxed by aqueous fluids from the subducted Paleo-Asian oceanic slab. The newly unmasked lithospheric mantle under the western NCC contrasts with the coeval thick and refractory one supporting the eastern NCC, and highlights that the craton destruction, especially the loss of its ancient refractory mantle root, should take place in a diachronous manner related to the craton-girded subduction episodes. Our study illustrates the potential of enriched basalts to recover the nature and evolution of mantle lithosphere beneath craton m

关键词： Enriched basalts Lithospheric mantle Northwest North China Craton Tectonic histories Early Cretaceous

Assembling S-scheme heterojunction between basic bismuth nitrate and bismuth tungstate with promoting charges’separation for accelerated photocatalytic sulfamethazine degradation

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Journal of Materials Science & Technology 2024年第4期171卷 185-197页

作者： Wenhan Chen Meng dai Li xiang Shan Zhao Shuguang Wang Zuoli He Shandong Key Laboratory of Water Pollution Control and Resource Reuse Shandong Key Laboratory of Environmental Processes and HealthSchool of Environmental Science and EngineeringShandong UniversityQingdao 266237China CEDAR Knight Cancer InstituteSchool of MedicineOregon Health and Science UniversityPortlandOR 97201United States Weihai Research Institute of Industrial Technology of Shandong University Shandong UniversityWeihai 264209China

The S-scheme heterojunction has garnered increasing attention due to its remarkable oxidation capacity and efficient separation of photogenerated *** this study,a one-pot glycerol-assisted hydrothermal process was utilized to successfully synthesize S-scheme heterojunction photocatalysts comprising basic bismuth nitrate(BBN)and bismuth tungstate(BWO).Interestingly,the BBN/BWO heterogeneous photo-catalysts exhibited the highest photocatalytic *** optimized product achieved the degradation of sulfamethazine(SMZ)within 1 h,with a kinetic constant(k)value of 0.05818 min^(−1).The degradation process was influenced significantly by·O^(2)−and h^(+)*** determine the degradation pathway of SMZ in the presence of BBN/BWO-0.6,liquid chromatography-mass spectrometry(LC-MS)analysis was performed,which revealed a decrease in the toxicity of intermediates and *** enhanced pho-tocatalytic activity can be attributed to the internal electric field(IEF)of the S-scheme heterojunction between BBN and BWO,effectively promoting the separation of photogenerated *** research presents a viable approach for developing S-scheme heterojunctions in SMZ photodegradation and other environmental applications.

关键词： Photocatalysis S-scheme Heterojunction Bi_(2)WO_(6) Sulfamethazine

A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2893-2915页

作者： Shen Yan Dajiang Geng Ning dai Mingjian long Zhicheng Bai College of Civil Engineering Tongji UniversityShanghai200092China China Construction 4th Engineering Bureau 6th Corp. Ltd.Shanghai201199China Department of Civil and Architecture Engineering Hubei Polytechnic UniversityHuangshi435003China

According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock *** address this challenge,a subterranean transfer structure spanning multiple subway tunnels was *** on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam *** resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer *** research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent *** established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate *** pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment.

关键词： Crossing tunnels transfer structure force mechanism simplify analysis layered soil mass

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： xiang-long Liang Zhi-kai Yao Yao-wen Ge Jian-yong Yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan xiang Wen-long Zhang He-Ting Li Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

Anchoring heterometallic cluster on P-doped carbon nitride for efficient photocatalytic nitrogen fixation in water and air ambient

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Chinese Chemical Letters 2024年第4期35卷 176-180页

作者： Chao-long Chen Rong Chen La-Sheng long Lan-Sun Zheng xiang-Jian Kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Light-driven nitrogen fixation to produce ammonia is a green and economical technology of nitrogen reduction but is still quite challenging, especially in an air atmosphere without any sacrificial ***, we demonstrate efficient photocatalytic nitrogen fixation using water and air directly by loading lanthanide–transition metal(4f–3d) cluster NdCo_(3) on two-dimensional P-doped graphitic carbon nitrides(PCN) material surface. Benefiting from the increase in the number of nitrogen vacancies(NVs) and highly matched band gap structure and excellent hole trapping ability of clusters, the NdCo_(3)/PCN photocatalyst exhibits efficient nitrogen reduction activity with 371(in air) and 825 μmol h^(-1)g^(-1)(in pure nitrogen)without any sacrificial reagents. The introduction of potassium sulfate inhibits hydrogen production and promotes nitrogen reduction activation. This work suggests that anchoring precisely structured clusters on 2D materials may enhance photocatalytic nitrogen reduction under normal temperature and pressure.

关键词： Photocatalytic Nitrogen fixation 4f-3d Cluster Air atmosphere