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Research on the Method of Heat Preservation and Heating for the Drilling System of Polar Offshore Drilling Platform

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Energy Engineering 2024年第5期121卷 1173-1193页

作者： Yingkai Dong Chaohe Chen guangyan jia Lidai Wang jian Bai Oil and Gas Research and Development Center CIMC RAFFLESYantai264000China school of Civil Engineering and Transportation South China University of TechnologyGuangzhou510641China Yantai Hangxiao Steel Structure Assembly Construction Co. Ltd.Yantai264000China

This study investigates the heat dissipation mechanism of the insulation layer and other plane insulation layers in the polar drilling rig *** the basic theory of heat transfer with the environmental requirements of polar drilling operations and the characteristics of polar drilling processes,we analyze the factors that affect the insulation effect of the drilling rig *** factors include the thermal conductivity of the insulation material,the thickness of the insulation layer,ambient temperature,and wind *** optimize the thermal insulation material of the polar drilling rig system using a steady-state method to measure solid thermal *** analyzing the distribution of temperature in space after heating,we optimize the distribution and air outlet angle of the heater using Fluent hydrodynamics *** results demonstrate that under polar conditions,polyisocyanurate with stable thermodynamic properties is selected as the thermal insulation *** selection of thermal insulation material and thickness significantly affects the thermal insulation effect of the system but has little effect on its heating ***,when the air outlet angle of the heater is set to 3..5°,the heating efficiency of the system can be effectively *** to heat transfer equations and heat balance theory,we determine that the heating power required for the system to reach 5°C is close to numerical simulation.

关键词： Polar drilling drilling system fluid dynamics heat preservation and heating numerical simulation

Effects of two silicone resin coatings on performance of FeSiAl magnetic powder cores

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Journal of Iron and Steel Research International 2024年第5期31卷 1279-1288页

作者： jia-qi Liu Zheng-qu Zhu Pu Wang Yi-fan Li Jing Pang jia-quan Zhang school of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao266232ShandongChina

Two silicon resins with excellent thermal stability,JH1123.and JH7102,are used as the insulated agents and binders for the gas-atomized FeSiAl powder,and corresponding magnetic powder cores(MPCs)are *** insulation capability and application prospects of the two silicon resins are evaluated by comparing the magnetic properties of the coated powder and *** scanning electron microscopy,energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy results show that uniform insulation layers are both formed on the powder ***1123.has stronger binding ability,and the JH1123.coated powder exhibits severe agglomeration,with d50(average particle size)approximately twice that of the JH7102-coated *** as-prepared MPCs exhibit outstanding soft magnetic ***,the permeability of FeSiAl@JH1123.is up to 74.0,which is 3..5%higher than that of FeSiAl@JH7102 because JH1123.can further improve the density of the *** for FeSiAl@JH7102,it has better direct current bias and lower core loss of 716.9 mW cm^(−3. at 20 mT and 1000 kHz due to its lower coercivity and greater anti-magnetic saturation ability.A comprehensive comparison shows that FeSiAl@JH1123.is suitable for medium and high frequency applications,while FeSiAl@JH7102 is more suitable for high frequency *** indicates that the use of JH1123.and JH7102 silicon resins for binding and insulated coating not only simplifies the preparation process of MPCs,but also enables the controlled production of MPCs for different applications.

关键词： FeSiAl Insulated coating Magnetic powder core Permeability Core loss

Polymorphic cerium-based Prussian blue derivatives with in situ growing CNT/Co heterojunctions for enhanced microwave absorption via polarization and magnetization

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Nano Research 2024年第3期17卷 2050-2060页

作者： Jixi Zhou Xinmeng Huang Di Lan Yuhang Cheng Fengyi Xue Chenyu jia Guanglei Wu Zirui jia Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China school of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

In this paper,the structure evolution of cerium cobaltohexanoate(Ce[Co(CN)6],Ce-Co Prussian blue analog(PBA))has been realized by solvent catalysis at room *** hexagonal bipyramidal microcrystals of Ce-Co PBA can be gradually transformed into dendrites by different proportions of ethanol(EtOH)and *** the same time,the porous dendrites CeO_(2)/Co@carbon nanotub(CNT)with oxygen-rich vacancies(OVs)can be obtained by annealing Ce-Co PBA at 700℃.The microstructure study shows that carbon nanotubes will be catalyzed after annealing at high temperature,and the cobalt metal particles encapsulated in carbon nanotubes will be anchored in the matrix,regulating the impedance matching and multi-polarization suppression of the material,and its unique structure,vacancies,and strong interface effect make the material exhibit excellent electromagnetic wave(EMW)absorption *** the matching thickness is 2.5 mm,the minimum reflection loss(RLmin)of the composite is-51.68 dB,and the effective absorption bandwidth(RL<-10 dB)is 7.76 *** results show that the prepared CeO_(2)/Co@CNT composite has excellent EMW absorption *** is expected to be a candidate material for EMW absorption.

关键词： Ce-Co Prussian blue analog(PBA) carbon nanotubes(CNTs) CeO_(2)/Co@CNT solvent catalysis electromagnetic wave absorption

Nitric oxide assists nitrogen reduction reaction on 2D MBene: A theoretical study

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Chinese Chemical Letters 2024年第5期35卷 428-433页

作者： Chaozheng He jia Wang Ling Fu Wei Wei Henan Engineering Center of New Energy Battery Materials College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu 476000China school of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage&Novel Cell TechnologyLiaocheng UniversityLiaocheng 252059China Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi’an Technological UniversityXi’an 710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui 741001China

Electrocatalytic synthesis of ammonia as an environment-friendly and sustainable development method has received widespread attention in recent ***-dimensional(2D)materials are a promising catalyst for ammonia synthesis due to their large surface *** this work,we have constructed a series of 2D metal borides(MBenes)with transition metal(TM)defects(TMd-MBenes)and comprehensively calculated the reactivity of electrocatalytic synthesis of ammonia-based on density functional *** results have demonstrated that the TMd-MBenes can effectively activate nitrogen oxide(NO)and nitrogen(N2)molecules *** interesting,the co-chemisorption of O atoms,dissociated from NO,can facilitate the spilled of the inert N2 molecules into single N atoms,which can further hydrogenate into ammonia easily with an ultralow limiting potential of 0.59 V on *** research has not only provided clues for catalyst design for experimental study but also paved the way for the industrial application of electrocatalytic ammonia synthesis.

关键词： 2D mbenes Nitrogen electro-reduction DFT N_(2)activation Ammonia synthesis

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Palladium Complexes with N,O-Bidentate Ligands Based on N-Oxide Units from Cyclic Secondary Amines:Synthesis and Catalytic Application in Mizoroki-Heck Reaction

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Chinese Journal of Chemistry 2024年第3期42卷 294-300页

作者： Xuefeng jia Yanyan Wen Changhui He Xianqiang Huang Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi030032 China shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry & Chemical EngineeringLiaocheng UniversityLiaochengShandong252059 China

Palladium-catalyzed Mizoroki-Heck reaction is a powerful and efficient method for construction of Csp2–Csp2 ***,four palladium complexes(I—IV)with N,O-bidentate ligands(L1—L4)based on N-oxide units from cyclic secondary amines were easily synthesized and successfully applied in Mizoroki-Heck reaction of aryl bromides with electron-deficient olefins.X-ray diffraction analyses indicated the palladium(II)atom of II took the distorted square planar geometry and was four-coordinated by nitrogen and oxygen atoms from two ligands(L2).Two free chloride ions were presented as counter anions in complex *** the palladium(II)center of IV was coordinated by nitrogen and oxygen atoms from one ligand(L4)as well as two chlorine atoms,which exhibited the nearly square-planar *** study on catalytic properties of palladium complexes revealed that complex II exhibited high activity superior to the other *** coupling reactions of a series of aryl bromides and olefin derivatives proceeded in the presence of 2—5 mol%palladium complex II,giving the desired products in good to excellent *** advantages of this method such as good compatibility of functional groups,high yields,and short reaction times made it more attractive for constructing Csp2–Csp2 bonds in the synthesis of functional molecules and materials.

关键词： Palladium complexes N,O-Bidentate ligands N-Oxide units Mizoroki-Heck reaction Aryl bromide Electron-deficient olefins C—C coupling Homogeneous catalysis Substituent effects

Lead-free perovskites-based photonic synaptic devices with zero electric energy consumption

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Science China(Information Sciences) 2024年第6期67卷 433-441页

作者： Dandan HAO Di YANG Haixia LIANG jia HUANG Fukai SHAN College of Electronics and Information Qingdao University Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences school of Materials Science and Engineering Tongji University National Key Laboratory of Autonomous Intelligent Unmanned Systems Tongji University

The von Neumann bottleneck is a critical limitation in synaptic devices. Therefore, artificial synaptic devices resembling biological neuromorphic synapses have been developed to overcome the von Neumann bottleneck. However, synaptic devices require voltages, which results in considerable energy consumption. Here, photonic synaptic devices with the vertical structure of indium tin oxide（ITO）/SnO2/Al2O3.CsBi3.10/Au are fabricated, which can work in the self-powered mode owing to the photovoltaic effect endowed by a vertical multilayer structure. Several fundamental synaptic functions, such as excitatory postsynaptic current, paired-pulse facilitation, short-term plasticity（STP）, long-term plasticity（LTP）, pulse-frequency-dependent plasticity, transition of STP to LTP, and the learning experience are emulated. Moreover, Morse-coded external light information is decoded by self-powered photonic synaptic devices. The results indicate that self-powered photonic synaptic devices based on lead-free perovskites exhibit great potential for efficient neuromorphic computing and optical wireless communication.

关键词： photonic synaptic devices lead-free perovskites zero energy consumption synaptic plasticity Morse code

An elastic organic crystal with piezochromic luminescent behavior

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Chinese Journal of Structural Chemistry 2024年第6期43卷 25-27页

作者： jiakun Bai Junhui jia Aisen Li Key Laboratory of Magnetic Molecules and Magnetic Information Material Ministry of EducationCollege of Chemistry and Material ScienceShanxi Normal UniversityTaiyuan030032China school of Physical Science and Information Technology Shandong Key Laboratory of Optical Communication Science and TechnologyLiaocheng UniversityLiaocheng252059China

Organic crystals have become ideal candidates as smart materials due to their flexibility and responsive characteristics[1].Among them,organic crystals with piezochromic behavior demonstrate alterations in color under external *** are capable of serving as pressure sensing and optical recording systems,enabling real-time visual repre-sentation of pressure responses,and thus have attracted significant in-terest from researchers[2].However,conventional organic single crystals with piezochromic behavior typically exhibit weak luminescence under external pressure,which is attributed to pressure-induced increase ofπ-πstacking interactions,thus leading to non-radiative decay[3..

关键词： behavior attributed crystal

Structure attack on full-round DBST

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Frontiers of Computer Science 2024年第4期18卷 223-225页

作者： Chenhao jia Qing LING Ting WU Tingting CUI school of Cyberspace Hangzhou Dianzi UniversityHangzhou 310018China Hangzhou Innovation Institute Beihang UniversityHangzhou 310052China Key Laboratory of Cryptologic Technology and Information Security(Ministry of Education) Shandong UniversityQingdao 266237China

1 Introduction Block cipher is one of the most important part of symmetric cipher,which has been widely used in the field of computer communication and information system *** order to meet the increasing demand for ensuring secure data transmission in Internet of Things(IoT)environment,lightweight block ciphers have become more and more important due to their easy software implementation,low resource consumption,ease of standardization and high ***,in order to satisfy the constraints of resource-limited devices,lightweight block ciphers strive to achieve a balance between the cost of software and hardware implementation,efficiency,and ***,sometimes the security of lightweight block ciphers might be challenged due to the simplified ***,it is meaningful to study the type of simplified lightweight block ciphers.

关键词： hardware computer simplified

Characteristics and Preliminary Causes of Tropical Cyclone Remote Precipitation over China

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Journal of Ocean university of China 2024年第4期23卷 845-858页

作者： jia Li REN Fumin MCBRIDE John Leonard CONG Chunhua school of Atmospheric Science Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China school of Earth Science University of MelbourneMelbourne 3052Australia Research and Development Division Bureau of MeteorologyMelbourne 3052Australia shandong Meteorological Bureau Jinan 250031China

In this study,the characteristics and preliminary causes of tropical cyclone remote precipitation(TRP)over China during the period from 1979 to 2020 are *** indicated that approximately 72.42%of tropical cyclones(TCs)in the Western Pacific produce TRP over *** peak months for TRP are July and *** four key regions of TRP are the adjacent areas between the Sichuan and Shaanxi Provinces,the northern coast of the Bohai Sea,the coast of the Yellow Sea,and the southern coast *** typical distance between the station with TRP and the TC center ranges from 1500 to 2500 *** of these stations are situated north to 60°west of north of the *** south–west water vapor transportation on the west side of the TC is crucial to *** has a decreasing trend because of the decrease in the number of TCs that generate *** the perspective of large-scale environmental conditions,a decrease in the integrated horizontal water vapor transport in China' Mainland,the weakening of upward motion at approximately 25°–3.°N,which is inconducive to convection,and an increase in low-level vertical wind shear,which is unfavorable for the development of TC in areas with high frequencies of TRP-related TCs,are the factors that result in the decreasing trend of TRP.

关键词： tropical cyclone remote precipitation characteristics causes

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