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Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu Liu jun yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

Magnetic nanoparticle-modified hollow double-shell SiC@C@FeCo with excellent electromagnetic wave absorption

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Nano Research 2024年第4期17卷 3164-3174页

作者： Guiyu Peng Jintang Zhou Jiaqi Tao Weize Wang jun Liu junru yao Yijie Liu Zhengjun yao College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100China Key Laboratory of Material Preparation and Protection for Harsh Environment(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 211100China

Integrated micro and nanostructures,heterogeneous components,defects,and interfaces is the way to develop high-performance microwave absorbing ***,there still needs to be more precise experimental routes and effective *** this work,by a continuous process of vacuum sintering,hydrothermal,and carbon thermal reduction,magnetic FeCo nanoparticles were successfully embedded on the hollow double-shell mesoporous SiC@C surface,thus solving the challenges of a single component loss *** hollow double-shell nanostructure introduces air to enhance impedance matching while significantly reducing the density of the *** extensive defects and heterogeneous grain boundaries effectively enhance the polarization loss *** magnetic loss mechanism introduced by the magnetic particles effectively improves the impedance matching properties of the *** synergy of these multiple advantages has enabled the SCFC_(2)-8(here SiC@C@FeCo is abbreviated to SCFC,2 represents the initial metal ion content,and 8 represents the hydrothermal time)sample to achieve an adequate absorption bandwidth of 6.09 GHz at 2.0 *** a minimum reflection loss of-60.56 dB,the absorption bandwidth can cover the entire C,X,and Ku bands by adjusting the matching thickness(1.3–4.0 mm).This work provides a valuable paradigm for the deeper exploitation of microwave absorption potential and guides the development of other high-performance materials.

关键词： SiC@C@FeCo(SCFC)composites core–shell hollow structure microwave absorption

Dynamic Couplingand Cooperative Control for Multi-paralleled Doubly Fed Induction Generator Wind Farms during Symmetrical Low Voltage Ride-through in a Weak Grid

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Protection and Control of Modern Power Systems 2024年第3期9卷 112-125页

作者： Lei Guan jun yao the College of Electrical Engineering at Chongqing University ChongqingChina the State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China

In multi-fed grid-connected systems,there are complex dynamic interactions between different pieces of *** in situations of weak-grid faults,the dynamic coupling between equipment becomes more *** may cause the system to experience small-signal instability during the fault *** this paper,multi-paralleled doubly fed induction generator(DFIG)-based wind farms(WFs)are taken as an example to study the dynamic coupling within a multi-fed system during fault steady-state of symmetrical low voltage ride-through(LVRT)in a weak *** analysis reveals that the dynamic coupling between WFs will introduce a damping shift to each *** inevitably affects the system’s dynamic stability and brings the risk of small-signal instability during fault steady-state in LVRT *** the distance to fault location and fault severity will exacerbate the dynamic coupling between *** of the dynamic coupling,adjusting the control state of one WF will affect the stability of the remaining WFs in the ***,a cooperative control strategy for multi-paralleled DFIG WFs is proposed to improve dynamic stability during *** analysis and the effectiveness of the proposed control strategy are verified by modal analysis and simu-lation.

关键词： Doubly fed induction generator(DFIG) wind farms(WFs) dynamic stability low voltage ride through(LVRT) weak grid dynamic coupling

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji Wang Ning Qi Hong-yao Yin Yu-jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

The interaction mechanism between zein and folic acid in alkaline aqueous solutions:an experimental and molecular simulation study

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Food Quality and Safety 2024年第1期8卷 166-178页

作者： jun Zhu Yiling yao Yuying Liao Lala Cai Wenqi Zhang Nuo Hong Wenlin Sun Chunhua Xiong Lanying yao School of Food Science and Biotechnology Zhejiang Gongshang UniversityHangzhouChina

Objectives:Folic acid is a vitamin that is not highly soluble in water and is sensitive to the ***,it is important to find suitable *** study aimed to exemplify the interaction of folic acid with zein in alkaline aqueous solutions and shed light on how zein can be used as a carrier for folic *** and Methods:Zein and folic acid were separately dissolved in NaOH solutions with a PH of *** solution and folic acid solution were combined in specific *** methods including multi-spectroscopy,dynamic light scattering,and electron microscopy combining with molecular dynamics simulations were used to study the interaction mechanism between zein and folic acid in alkaline aqueous ***:Fluorescence spectroscopy showed that the quenching of zein by folic acid was mainly static,and the main driving force behind this interaction was van der Waals forces and hydrogen *** formation of zein–folic acid complexes was confirmed by ultraviolet–visible spectroscopy,Fourier transform infrared spectroscopy,and circular dichroism *** results also showed that the structure of zein changed when it interacted with folic *** light scattering analysis revealed that the addition of folic acid caused proteins to *** aggregates of the complexes had an irregular shape and were large,as observed by scanning electron microscopy and transmission electron *** simulation was used to further investigate the interaction *** to these findings,the folic acid molecule interacted with zein in a shallow recess near the protein *** dominant forces at play in the zein–folic acid interaction were van der Waals forces and electrostatic forces,including hydrogen ***:The zein alkali-soluble system is very suitable for folic acid delivery.

关键词： Zein folic acid alkaline aqueous solutions molecular simulation interaction mechanism.

Cycloaddition Reactions of Epoxides and CO_(2)Catalyzed by Bifunctional Rare-Earth Metal Complexes Bearing Amino-Bridged Tris(phenolato)Ligands

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Chinese Journal of Chemistry 2024年第14期42卷 1571-1581页

作者： Yongjie Chen Yanwei Wang jun Nong Dan Yuan Yingming yao Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceDushu Lake CampusSoochow UniversitySuzhouJiangsu215123 China

Eight zwitterionic rare earth metal complexes stabilized by amino-bridged tris(phenolato)ligands bearing quaternary ammonium side-arms were synthesized and *** complexes were used as single-component catalysts for the cycloaddition of CO_(2)and epoxides,and their catalytic activities are obviously higher than those of their binary *** studies revealed that the halide anions(Cl^(–),Br^(–),I^(–))and the metal complexes influenced the catalytic activity,and the lanthanum complex bearing iodide anion showed the highest catalytic activity for this addition reaction.A variety of mono-substituted epoxides were converted to cyclic carbonates in good to excellent yields(55%—99%)with high selectivity(>99%)at 30℃and 1 bar CO_(2),whereas internal epoxides required higher both reaction temperatures(60—120℃)and catalyst loading(2 mol%)for high *** catalyst was recyclable for four times without noticeable loss of catalytic *** on the results of kinetic studies and in℃situ IR reactions,a plausible reaction mechanism was proposed.

关键词： Bifunctional catalyst Carbon dioxide Cyclic carbonate Rare-earth metal Tris(phenolato)ligand Insertion Cycloaddition C1 building blocks

Experimental Study on the Sinking and Leveling of A Large-Capacity Offshore Wind Turbine Five-Bucket Foundation in Sand

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China Ocean Engineering 2024年第4期38卷 586-601页

作者： LIAN Ji-jian ZHU Hang GUO yao-hua WANG Hai-jun YU Tong-shun State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Tianjin University of Technology Tianjin 300384China College of Engineering Ocean University of ChinaQingdao 266100China

As offshore wind farms expand into deeper and farther ocean regions and the unit capacity of offshore wind turbines(OWTs)increases,there is a pressing need for a new foundation structure that can accommodate deep-sea conditions and support large capacities while maintaining economical and *** meet this goal of integrated transportation and one-step installation,a novel five-bucket jacket foundation(FBJF),with its suction installation and leveling methods in sand,has been proposed,analyzed and experimentally ***,seepage failure experiments of the FBJF at various depths were conducted,and a formula for calculating the critical suction of seepage failure suitable for the FBJF in sand was chosen and recommended for use with a range of values for the permeability coefficient ***,through leveling experiments of the FBJF at different depths,the maximum adjustable leveling angle during the sinking process was defined using seepage failure and the adjustable leveling angle of the foundation as control *** leveling control strategies were proposed and ***,an automatic sinking and leveling control system for the FBJF was developed and experimentally verified for feasibility.

关键词： offshore wind turbine(OWT) bucket foundation seepage failure suction installation

Discovery of a potential bladder cancer inhibitor CHNQD-01281 by regulating EGFR and promoting infiltration of cytotoxic T cells

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Marine Life Science & Technology 2024年第3期6卷 502-514页

作者： Jian-Yu Liu yao-yao Jiang Peng-Jie Li Bo yao Yi-Jing Song Ji-Xiu Gao Gulab Said Yang Gao jun-Yu Lai Chang-Lun Shao Key Laboratory of Marine Drugs the Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Department of Critical Care Medicine the Affiliated Hospital of Qingdao UniversityQingdao 266003China Department of Chemistry Women University SwabiSwabi 23430Pakistan Laoshan Laboratory Qingdao 266237China Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China

As one of the common malignancies that threaten human life,bladder cancer occurs frequently with a high mortality rate in the world,due to its invasion,recurrence and drug *** products from marine microorganisms are becoming the hotspots in discovery of new candidate drug entities,especially in the area of *** A(BFA)is a natural Arf-GEFs inhibitor,but due to the low aqueous solubility,strong toxicity,and poor bioavailability,it is urgent to conduct structural optimization ***,a new BFA pyridine acrylate derivative CHNQD-01281 with improved solubility was prepared and found to exert moderate to strong antiproliferative activity on a variety of human cancer cell *** was noteworthy that CHNQD-01281 was most sensitive to two bladder cancer cell lines T24 and J82(IC50=0.079 and 0.081μmol/L)with high selectivity index(SI=14.68 and 14.32),suggesting a superior safety to *** vivo studies revealed that CHNQD-01281 remarkably suppressed tumor growth in a T24 nude mice xenograft model(TGI=52.63%)and prolonged the survival time(ILS=68.16%)in an MB49 allogeneic mouse model via inducing infiltration of cytotoxic T *** mechanism exploration indicated that CHNQD-01281 regulated both EGFR/PI3K/AKT and EGFR/ERK pathways and mediated the chemotactic effect of chemokines on immune effector ***,CHNQD-01281 may serve as a potential therapeutic agent for bladder cancer through multiple mechanisms.

关键词： Bladder cancer Marine natural products Brefeldin A EGFR/PI3K/AKT EGFR/ERK T-cell infiltration

Effects of soil metal(loid)s pollution on microbial activities and environmental risks in an abandoned chemical smelting site

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Journal of Environmental Sciences 2024年第9期143卷 60-70页

作者： Hao Li jun yao Jianli Liu Ning Min Geoffrey Sunahara Dongyang Men Robert Duran School of Water Resources and Environment Research Center of Environmental Science and EngineeringChina University of Geosciences(Beijing)Beijing 100083China Department of Natural Resource Sciences McGill University21111Lakeshore DriveSte-Anne-de-BellevueQuebecH9X 3V9Canada Equipe Environnement et Microbiologie MELODY groupUniversitéde Pau et des Pays de l’AdourE2S-UPPAIPREM UMR CNRS 5254BP 115564013 Pau CedexFrance

Abandoned chemical smelting sites containing toxic substances can seriously threaten and pose a risk to the surrounding ecological *** samples were collected from different depths(0 to 13 m)and analyzed for metal(loid)s content and fractionation,as well as microbial *** potential ecological risk indices for the different soil depths(ordered from high to low)were:1 m(D-1)>surface(S-0)>5 m(D-5)>13 m(D-13)>9 m(D-9),ranging between 1840.65-13,089.62,and representing extremely high environmental risks,of which Cd(and probably not arsenic)contributed to the highest environmental risk.A modified combined pollution risk index(MCR)combining total content and mobile proportion of metal(loid)s,and relative toxicities,was used to evaluate the degree of contamination and potential environmental *** the near-surface samples(S-0 and D-1 layers),the MCR considered that As,Cd,Pb,Sb,and Zn achieved high and alarming degrees of contamination,whereas Fe,Mn,and Ti were negligible or low to moderate pollution *** microcalorimetry and enzymatic activity measurements of contaminated soil samples were used to assess the microbial metabolic activity *** analysis elucidated the relationship between metal(loid)s exchangeable fraction or content and microbial activity characteristics(p<0.05).The microbial metabolic activity in the D-1 layer was low presumably due to heavy metal *** activity indicators and microcalorimetric growth rate(k)measurements were considered sensitive indicators to reflect the soil microbial activities in abandoned chemical smelting sites.

关键词： Abandoned chemical smelting sites Microbial activities Modified combined pollution risk Microcalorimetry Enzymatic activities