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Characterizations of semihoops based on derivations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 291-310页

作者： wang mei ZHANG Xiao-hong School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Weinan Normal UniversityWeinan 714099China

In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of ***,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative ***,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence.

关键词： (prelinear)semihoop derivation Heyting algebra Galois connection

Inherently Chiral and Symmetrical Heteroatom-Doped Zigzag-Type Hydrocarbon Belts

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CCS Chemistry 2024年第5期6卷 1198-1210页

作者： Xue-Yuan wang Xin-Yu Zhang Shuo Tong Qing-hui Guo mei-Ling Tan Cheng-Jun Li mei-Xiang wang Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084

hydrocarbon belts due to their potential applications in carbon *** contrast,heteroatomembedded zigzag hydrocarbon belts as advanced design strategies with fascinating structures and desirable,unique properties have remained largely unexplored,and inherently chiral ones are ***,we report the synthesis of a diversity of symmetric and highly enantiopure inherently chiral O-and N-doped zigzag-type hydrocarbon belts starting from strainless macrocycles based on fjord-stitching *** readily available pertriflated resorcin[6]arene underwent partial hydrolyses and intramolecular S_(N)Ar reactions to form a calix[3](9H-xanthene)derivative and a prochiral half-belt *** transformations of calix[3](9H-xanthene)into C_(3v)-symmetric molecular belts were achieved by closing the rest of the fjords with triple intramolecular S_(N)Ar reactions and Yamamoto homo coupling reactions,as well as palladiumcatalyzed intermolecular acridination reactions with primary *** prochiral half-belt underwent enantioselective desymmetrizative mono-acridination to afford an inherently chiral N,O_(4)-bridged pseudo-belt with an enantiomeric excess(ee)value of>99%under the catalysis of Pd(OAc)_(2)and(R)-*** closure reactions of the pseudo-belt produced diverse heteroatom-inlayed zigzag-type hydrocarbon belts of inherent ***,we showed the unique cavity structures of the belts and demonstrated interesting chiroptic properties of the inherently enantiopure chiral *** research opens the door for the exploration of novel and sophisticated symmetric and inherently chiral molecular nanobelt structures with outstanding physical and chemical properties,as well as potential applications.

关键词： zigzag-type molecular belt heterocycle chiroptical property fjord-stitching strategy resorcinarene

Vibration attenuation performance of wind turbine tower using a prestressed tuned mass damper under seismic excitation

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： Lei Zhenbo Liu Gang wang hui hui Yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the *** addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

Data-Driven Design for Targeted Regulation of Heat Transfer in Carbon/Carbon Composite Structure

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Journal of Thermal Science 2024年第2期33卷 648-657页

作者： XIAO Heye wang Zelin wang hui JI Ritian Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China

Targeted regulation of heat transfer in carbon/carbon composite structure is built for cooling electronic device.A three-dimensional data-driven design model coupling genetic algorithm(GA) with self-adaption deep learning for targeted regulation of heat transfer in built structure is *** self-adaption deep learning model predicts the temperature of built structure closer to optimal value in GA *** distributions of pore and carbon fiber bundles in built structure are optimized by the proposed *** surface temperature of electronic device in the optimized structures is 19.1%-27.5% lower than that in the initial configurations when the porosity of built structure varies from 3% to 11%.The surface temperature of electronic device increases with an increase in *** built structure with carbon fiber bundles near the surface of electronic device and pore distribution in the middle of structure has a higher heat dissipation capacity compared with that in the initial ***,the computation time of the proposed model is less than one tenth compared with that of the traditional genetic algorithm.

关键词： targeted regulation of heat transfer self-adaption deep learning genetic algorithm carbon/carbon composite structure

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

Graphene from microwave-initiated upcycling of waste polyethylene for electrocatalytic reduction of chloramphenicol

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Chinese Chemical Letters 2024年第4期35卷 187-192页

作者： Qiang Cao Xue-Feng Cheng Jia wang Chang Zhou Liu-Jun Yang Guan wang Dong-Yun Chen Jing-hui He Jian-mei Lu College of Chemistry Chemical Engineering and Materials ScienceCollaborative Innovation Center of Suzhou Nano Science and TechnologySoochow UniversitySuzhou 215123China

Waste polyolefin plastics, accounting for 50% of all plastic waste, represent a tremendously unexploited carbon source. Efficiently upcycling polyolefin waste into value-added carbon materials for waste water treatment avoiding using noble metals is challenging but economically and environmentally sustainable. In this work, MAX-Ti_(3)AlC_(2) supported Fe selectively catalyzes polyolefin into few-layered graphene in 5 min under microwave treatment. Graphene and MAX supported Fe(Fe@MLC) can completely(99.9%)degrade chloramphenicol(CAP) within 60 min, retain robust after 10 cycles and work efficiently at a wide p H range(3.87–13.03), avoiding the usage of noble metal. Moreover, the electrochemical active surface area(ECSA) of Fe@MLC is 2.7 times higher than that of commercial Pt/C. This work provides a cheap and efficient catalyst that promotes deconstruction of plastic wastes and indirectly degrades antibiotics thereby realizes the treatment of waste water with waste plastic.

关键词： Microwave Ti_(3)AlC_(2) Electrochemistry Dechlorination Chloramphenicol

Synergistic extraction and separation of thorium from rare earths in chloride media using mixture of Cextrant 230 and Cyanex 923

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Journal of Rare Earths 2024年第4期42卷 759-767页

作者： hui wang Shengting Kuang Wuping Liao School of Rare Earths University of Science and Technology of ChinaHefei230026China Institute of Material and Chemistry Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou341000China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

In order to lower the usage of expensive Cyanex 923 and increase the extraction capacity of the system of Cextrant 230,the synergistic extraction of thorium from chloride media by a mixture of Cextrant 230 and Cyanex 923 was *** maximum synergistic enhancement coefficient(R)of 1.53 is obtained at 1:1 molar ratio of Cextrant 230/Cyanex *** syne rgistic extracted species of Th^(4+)is determined as ThCl_(4)·2Cextrant 230·Cyanex *** synergistic extraction of Th^(4+)is an entropy-driven exothermic *** loading capacity of 0.60 mol/L mixed extractant for thorium is about 17.10 g/L(calculated as ThO_(2)),and the loaded thorium in the organic phase can be effectively stripped by distilled *** comparison,rare earth cations are barely extracted under the similar conditions,suggesting that the mixtures can be applied to separate thorium from rare earths.A cascade extraction process was developed based on the synergistic extraction system to separate thorium from the hydrochloric acid leaching of *** content of thorium in the leaching solution decreases obviously from 19.90 mg/L to1.4μg/L by 3 stages of extraction,which is superior to sole Cextrant 230 or Cyanex *** introduction of Cextrant 230 into the extraction system not only lowers the usage of Cyanex 923 but also enhances the selective extraction of thorium at low acidity,implying that the synergistic extraction system can selectively extract thorium more efficiently and economically than the sole systems.

关键词： Synergistic extraction Cextrant 230 Cyanex 923 Thorium Rare earths

A new method for identifying flow pattern of spouted fluidized bed by coupling Hilbert-Huang transform characteristics of differential pressure signals in different zones

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Particuology 2024年第6期89卷 67-78页

作者： Yongzhi mei Yang wang Lihui Zhang Feng Duan School of Energy and Environment Anhui University of TechnologyMaanshan243002China Wuhu Technology and Innovation Research Institute Wuhu241000China Wuhu Cigarette Factory of China Tobacco Anhui Industrial Co. Ldt.Wuhu241002China

On a cold spouted fluidized bed,this study compares the characteristic differences in intrinsic mode function(IMF)energy and Hilbert–Huang spectrum between the spout zone and annulus zone under different combinations of spouted gas and fluidized gas flow rates for five typical flow *** energy distribution characteristics under different flow patterns are also *** Hilbert–Huang spectrum and IMF energy of pressure difference signals exhibit distinct variations in different zones as the flow pattern ***,there exists a correlation between the energy in the middle-frequency range and the flow *** the K-means algorithm,the middle-frequency range energy of IMFs in the spout zone and annulus zone is subjected to clustering analysis,leading to the identification of partition boundaries for each flow *** on this,a flow pattern identification method of spouted fluidized bed coupled with middle-frequency range energy in spout zone and annulus zone is proposed,which has very high identification accuracy.

关键词： Spouted fluidized bed Flow pattern Zoning signal Flow pattern transition Hilbert-Huang transform

Comparison of nonlinear modeling methods for the composite rubber clamp

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 763-778页

作者： Yiming CAO hui MA Xumin GUO Bingfeng ZHAO hui LI Xin wang Bing wang School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China AVIC Shenyang Engine Design Institute Shenyang 110013China Dalian Mengyu Machinery Co. Ltd.Dalian 116317Liaoning ProvinceChina

The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared *** unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with *** fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are *** results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant ***,the optimization time of the BWM is longer than that of the CSFM.

关键词： pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment