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Chinese Journal of Polymer Science 2024年第8期42卷 1227-1242页

作者： Jia-Wei Gao Li Chen Ye-Shun zhong Chao-Wei Xing yi-Guo Li Zong-Bao wang School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

Shish crystals are crucial to achieving high performance low-dimensional ultra-high molecular weight polyethylene(UHMWPE)***,high stretch and shear flow fields are necessary for the formation of shish *** this study,UHMWPE gel films with reserved shish crystals were prepared by gel molding,the structural evolution and properties of UHMWPE films stretched at temperatu res of 100,110,120and 130℃were investigated by in situ small-angle X-ray scattering(SAXS)/ultra-small-angle X-ray scattering(USAXS)/wide-angle X-ray diffraction(WAXD)measu rements as well as scanning electron microscopy(SEM)and differential scanning calorimetry(DSC)*** findings showed that the reserved shish crystals can facilitate the formation and structural evolution of shish-kebab crystals during the hot ***,the reserved shish crystals promote the structu ral evolution of UHMWPE films to a greater extent when stretched at 120 and 130℃,compared to 100 and 110℃,resulting in higher crystallinity,orientation,thermal properties,breaking strength and Young's *** pared to UHMWPE high-entangled films with reserved shish crystals prepared by compression molding,UHMWPE low-entangled films with reserved shish crystals prepared by gel molding are more effective in inducing the formation and evolution of shish-kebab crystals during the hot stretching,resulting in increased breaking strength and Young's modulus.

关键词： UHMWPE low-entangled films Reserved shish crystals Structural evolution Hot stretching

A new approach to the synthesis of diacetals(diketals) pentaerythritol catalyzed by SO_3H-functionalized ionic liquids

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Chinese Chemical Letters 2010年第5期21卷 524-528页

作者： Yuan Yuan wang,Yan Nan Xu,Zhi zhong wang,Li yi Dai Shanghai Key Laboratory of Green Chemistry and Chemical Process,Department of Chemistry, East China Normal University,Shanghai 200062,China Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 China

In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was *** ILs show high catalytic activity and reusability with good to excellent yields of the desired *** method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization *** product yield of 93%was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss.

关键词： SO3H-functionalized ionic liquids Diacetals(diketals) pentaerythritol Catalyze Hammett method Reusability

Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network

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Journal of Ocean University of China 2024年第3期23卷 654-660页

作者： wang Fangchen zhong Guoqiang wang Liang College of Computer Science and Technology Ocean University of ChinaQingdao 266100China College of Marine Technology Ocean University of ChinaQingdao 266100China

Underwater pulse waveform recognition is an important method for underwater object *** existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform *** propagation channels in seawater are time-and space-varying convolutional *** the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent *** propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform *** the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is *** constraint can ensure that the influence of convolutional channels on hash features is *** addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash *** results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP.

关键词： convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition

Effect of interplanetary magnetic field B_(x)on the polar electrojets as observed by CHAMP and Swarm satellites

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Earth and Planetary Physics 2024年第2期8卷 382-390页

作者： Hui wang ChengZhi wang YunFang zhong Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

Based on 16 years of magnetic field observations from CHAMP and Swarm satellites,this study investigates the influence of the Interplanetary Magnetic Field(IMF)Bx component on the location and peak current density of the polar electrojets(PEJs).We find that the IMF Bx displays obvious local time,seasonal,and hemispherical effects on the PEJs,as follows:(1)Compared to other local times,its influence is weakest at dawn and dusk.(2)In the midnight sectors of both hemispheres,the IMF Bx tends to amplify the westward PEJ when it is0 in the Southern Hemisphere;this effect is relatively stronger in the local winter hemisphere.(3)At noontime,the IMF Bx intensifies the eastward current when it is0,it reduces the westward current;this effect is notably more prominent in the local summer hemisphere.(4)Moreover,the noontime eastward current shifts towards higher latitudes,while the midnight westward current migrates towards lower latitudes when IMF Bx is0 in the Southern Hemisphere.

关键词： polar electrojet interplanetary magnetic field Bx local time asymmetry hemispheric difference

Grain boundary engineering for enhancing intergranular damage resistance of ferritic/martensitic steel P92

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Nuclear Science and Techniques 2024年第5期35卷 186-199页

作者： Lei Peng Shang-Ming Chen Jing-yi Shi Yong-Jie Sun yi-Fei Liu yin-zhong Shen Hong-Ya He Hui-Juan wang Jie Tian State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China School of Materials Engineering Shanghai University of Engineering Science333 Long Teng RoadShanghai 201620China Experimental Center of Engineering and Material Science University of Science and Technology of ChinaHefei 230026China

Ferritic/martensitic(F/M)steel is widely used as a structural material in thermal and nuclear power ***,it is susceptible to intergranular damage,which is a critical issue,under service *** this study,to improve the resistance to intergranular damage of F/M steel,a thermomechanical process(TMP)was employed to achieve a grain boundary engineering(GBE)microstructure in F/M steel *** TMP,including cold-rolling thickness reduction of 6%,9%,and 12%,followed by austenitization at 1323 K for 40 min and tempering at 1053 K for 45 min,was applied to the as-received(AR)P92 *** prior austenite grain(PAG)size,prior austenite grain boundary character distribution(GBCD),and connectivity of prior austenite grain boundaries(PAGBs)were *** to the AR specimen,the PAG size did not change *** fraction of coincident site lattice boundaries(CSLBs,3≤Σ≤29)and Σ3^(n) boundaries along PAGBs decreased with increasing reduction ratio because the recrystallization fraction increased with increasing reduction *** PAGB connectivity of the 6%deformed specimen slightly deteriorated compared with that of the AR ***,potentiodynamic polarization studies revealed that the intergranular damage resistance of the studied steel could be improved by increasing the fraction of CSLBs along the PAGBs,indicating that the TMP,which involves low deformation,could enhance the intergranular damage resistance.

关键词： Grain boundary engineering Ferritic/martensitic steel Prior austenite grain boundary character distribution Grain boundary connectivity Intergranular damage resistance

Self-adaptive gas flow and phase change behaviors during hydrate exploitation by alternate injection of N_(2) and CO_(2)

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Petroleum Science 2024年第3期21卷 2120-2129页

作者： Bo-Jian Cao yi-Fei Sun Hong-Nan Chen Jin-Rong zhong Ming-Long wang Ming wang Chang-Yu Sun Guang-Jin Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China School of Chemistry and Chemical Engineering Changsha University of Science&TechnologyChangsha410114HunanChina

Since hydrate resources play a part of the stratigraphic framework structure in sediments,establishing a safe and economic method for hydrates exploitation remains the primary challenge to this *** the proposed methods,the spontaneous displacement of CH_(4) from hydrate cages by CO_(2) seems to be a perfect mechanism to address gas production and CO_(2) storage,especially in today's strong demand for carbon reduction and replacing clean *** extensive lab researches,in the past decade,injecting a mixture of CO_(2) and small molecule gas has become a key means to enhance displacement efficiency and has great potential for ***,there is a lack of in-depth research on gas flow in the reservoir,while the injected gas always passes through low-saturated hydrate areas with high permeability and then occurs gas channel in a short term,finally resulting in the decreases in gas production efficiency and produced gas ***,we explored a new injection-production mode of alternate injection of N2 and CO_(2) in order to fully coordinate the advantages of N_(2) in enhanced hydrate decomposition and CO_(2) in solid storage and heat *** alternate"taking"and"storing"processes perfectly repair the problem of the gas channel,achieving self-regulation effect of CH_(4) recovery and CO_(2) *** 3-D experimental results show that compared to the mixed gas injection,CH_(4) recovery is increased by>50%and CO_(2) storage is increased by>70%.Additionally,this alternate injection mode presented a better performance in CH_(4) concentration of produced gas and showed outstanding N_(2) utilization ***,we analyzed its self-adaptive gas flow mechanism and proposed an application model of"one injection and multiple production".We look forward to this study accelerating the application of CO_(2)-CH_(4) replacement technology.

关键词： Hydrate Replacement CH_(4)recovery CO_(2)storage Reservoir remediation

Phosphorus-silicon-integrated electrolyte additive boosts cycling performance and safety of high-voltage lithium-ion batteries

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Chinese Chemical Letters 2024年第8期35卷 418-424页

作者： Mei-Chen Liu Qing-Song Liu yi-Zhou Quan Jia-Ling Yu Gang Wu Xiu-Li wang Yu-zhong wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

Safety and energy density are significant for lithium-ion batteries(LIBs),and the flammable organic elec-trolyte is one of the most critical causes of the safety problem of *** LiNi0.8 Co 0.1 Mn 0.1 O 2(NCM811)cathode with high capacity can improve the energy density,the interface stability between NCM811 cathode and electrolytes needs to be ***,we report a multifunctional additive,diethyl(2-(triethoxysilyl)ethyl)phosphonate(DETSP),which can suppress the flammability of the elec-trolyte and enhance the cycling stability of NCM811 cathode with a capacity retention of 89.9%after 400 cycles at 1 C,while that of the blank electrolyte is merely 61.3%.In addition,DETSP is compati-ble well with the graphite anode without impairing the electrochemical ***,the performance and safety of NCM811/graphite full cells are also *** and theoretical re-sults demonstrate that DETSP can scavenge acidic byproducts and is beneficial to form a stable cathode-electrolyte interface(CEI).Accordingly,DETSP can potentially be an effective solution to ameliorating the safety of the commercial electrolyte and improving the stability of high-voltage cathodes.

关键词： Electrolyte additive NCM Lithium-ion batteries Safety Cathode-electrolyte interface

A universal polymer-assisted route to fabricate Zr-doped TiO2 nanocomposite: boosting reactive desulfurization

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Tungsten 2024年第3期6卷 596-609页

作者： Yue Du Ping Li Zhi-yi zhong Wen-Xue Chen yi-Si Liu Yun-Long Xie Li-Na Zhou Kai wang Hubei Key Laboratory of Photoelectric Materials and Devices College of Material Science and Engineering Hubei Normal University National Laboratory of Solid State Microstructures Nanjing University College of Urban and Environmental Sciences Huangshi Key Laboratory of Prevention and Control of Soil Pollution Hubei Normal University School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University

A series of transition metal ion-doped TiO2composites were prepared by polyethyleneimine-assisted solvent-free *** to the similar electronegativity and ionic radius of Ti and Zr ions,the introduction of Zr element to TiO2can effectively improve its surface acidity and introduce more defect sites on the ***-fabricated Zr-doped TiO2nanocomposite exhibits the formation of Zr-Ti bond,strong surface acidity,connected mesoporous channels,and relatively high *** remarkable properties contribute to its adsorption-oxidation-desulfurization capacity toward thiophene-type sulfides,which can remove 500 ×10-6dibenzothiophene from the model fuel within 100 min at low reaction *** polymer-induced self-assembly method can reduce organic solvent usage,pollutant emissions,and energy consumption,which provides an efficient and practical way to prepare porous metal oxide-based catalysts in future.

关键词： Oxidative desulfurization Transition metal ion-doped TiO 2 nanocomposite Dibenzothiophene Solvent-free self-assembly method

Some Rotundities of Orlicz–Lorentz Spaces

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1893-1919页

作者： Wan zhong GONG Peng wang Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China

K-UR,K-LUR and K-R are the generalizations of UR,LUR and R respectively,which are of great significance in Banach space *** in Orlicz–Lorentz function spaceΛ_(ϕ,ω)^(◦)[0,γ)equipped with the Orlicz norm,the research methods of K-UR,K-LUR and K-R are much more complicated than those of UR,LUR and *** this paper we obtain some criteria of K-UR,K-LUR and K-R ofΛ_(ϕ,ω)^(◦)[0,γ)by means of the norm of dual space and H_(μ)property ofΛ_(ϕ,ω)^(◦)[0,γ).

关键词： Orlicz-Lorentz space Orlicz norm k-uniform rotundity locally k-uniform rotundity krotundity

Electrical characteristics of a fractional-order 3×n Fan network

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Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： Zhi-zhong Tan Xin wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory