检索结果-南通市图书馆

Photoinduced Bending and Curling m.tions in m.lecular m.crocrystals of Naphthyl m.ldrum.s Acid Derivative Based on e-to-Z Photoisom.rization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CHem.CAL ReSeARCH IN CHINeSe UNIVeRSITIeS 2024年第5期40卷 907-913页

作者： Zhang, Xiaowen Xu, Tianyi Zhang, Chenchen Tong, fei east China Univ Sci & Technol Frontiers Sci Ctr Materiobiol & Dynam Chem Sch Chem & Mol Engn Key Lab Adv MatFeringa Nobel Prize Scientist Join Shanghai 200237 Peoples R China east China Univ Sci & Technol Frontiers Sci Ctr Materiobiol & Dynam Chem Sch Chem & Mol Engn Joint Int Res Lab Precis Chem & Mol EngnFeringa N Shanghai 200237 Peoples R China

Dynam.c photoresponsive m.lecular crystals are prom.sing candidates for m.king intelligent devices and m.terials in the future. Here, we synthesized a new photoactive m.lecule (e)-2,2-dim.thyl-5-[3-(naphthalen-1-yl)allylide]-1,3-dioxane-4,6-dione [(e)-DNADD] that undergoes an e-to-Z photoisom.rization in both liquid solution and solids when exposed to visible light (405 nm.. Com.ared to the bulk crystals, the photoresponsive behavior in m.crocrystals was profoundly im.roved. Highly crystalline (e)-DNADD m.croplate crystals exhibit robust m.tions, including bending, curling, and coiling under light irradiation. The photoproduct conversion of the photochem.cal reaction in the m.croplate is no m.re than 20%, while the large bending curvature of the coiled illum.nated sam.les was estim.ted at approxim.tely 150-300 m.(-1), com.arable to som. photoactive nanowires. Our results indicate that shrinking crystal dim.nsions can boost the photoresponses in m.lecular crystals and provide a facile strategy for developing dynam.c m.lecular crystals at the m.croscopic scale.

关键词： Photochem.stry m.lecular crystal e-to-Z photoisom.rization Photoinduced m.tion DRIVeN SySTem

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co sy.ergistic catalysis in Cu NPs@m.Fs catalyst under m.ld conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chem.stry 2024年第5期67卷 1561-1568页

作者： Peng-fei Guo Ze-Long Liang y.e-e Jiao Hang Xu Bin Zhao Key Laboratory of Advanced energy m.terial Chem.stry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an im.ortant precursor used in the production of drugs for treating cancer,HIV,Alzheim.r's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxy.ehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel fram.work 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/therm.l stability.A stable fram.work allows it to encapsulate Cu nanoparticles(NPs)to form.Cu NPs@1-x(x=1,2,3,and 4)with varying loading am.unts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively cataly.e the reaction from.THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly m.ld *** corresponding catalytic activity can m.intain at least five recyclings and can be further applied to gram.scale ***,the efficient preparation of DHIQ cataly.ed by Cu NPs@1-3 could be realized even under air ***,the anticancer m.lecule precursor synthesis of 6,7-dim.thoxy-3,4-dihydroisoquinoline was also selectively cataly.ed by Cu NPs@*** investigations revealed that high catalytic perform.nce can be attributed to the stable fram.work and the sy.ergistic catalytic effect of the loaded Cu NPs and Co m.tal *** im.ortantly,this work represents the first exam.le of m.F catalysts for selectively therm.-catalytic DHIQ synthesis and dem.nstrates a sim.le approach to obtain efficient catalysts for selective oxy.ehydrogenation in the production of unsaturated com.ounds.

关键词： m.tal-organic fram.works Cu NPs@m.Fs 3 4-dihydroisoquinoline selective oxy.ehydrogenation sy.ergistic catalysis

Fuel cell stack design and m.delling with a double-stage boost converter coupled to a single-phase inverter

在线全文

学校读者我要写书评

暂无评论

CLeAN eNeRGy 2024年第1期8卷 188-196页

作者： elnagi, Basem.e. Ism.iel, Ahm.d m. m.nsour, Hany S. e. Abd-Alwahab, m. N. Suez Canal Univ Fac Engn Elect Engn Dept Ismailia 41522 Egypt

A com.rehensive proton-exchange m.m.rane fuel cell stack m.del was developed and integrated with a two-stage DC/DC boost converter. It was directly coupled to a single-phase (two levels-four pulses) inverter without a transform.r. The pulse-width m.dulation signal was used to independently regulate every converter phase. The converter was m.delled using a m.TLAB (R)/Sim.link (R) environm.nt and an appropriate voltage control m.thod. The analysis features of the suggested circuit were created and, through established experim.nts, the sim.lation results were verified. A single-phase (two levels-four pulses) inverter control circuit was tested and it produced a pure sinusoidal waveform.with voltage control. It m.tches the voltage of the network in term. of am.litude and frequency. A sinusoidal pulse-width m.dulation approach was perform.d using a single-phase (two levels-four pulses) pulse-width m.dulation inverter. The results dem.nstrated an enhancem.nt in the standard of the output wave and tuned the dead tim. with a reduction of 63 m. s com.ared with 180 m. s in conventional techniques. A com.rehensive m.del of a proton-exchange m.m.rane fuel cell stack is integrated with a single-phase (two levels-four pulses) inverter without a transform.r. Pulse-width m.dulation is used to independently regulate every converter phase. As a result, the dead tim. is reduced com.ared to conventional techniques. Graphical Abstract

关键词： Pem.fuel cell pulse-width m.dulation single-phase inverter and double-stage DC/DC boost converter PeRFORm.NCe SySTem

A holistic approach to im.roving safety for battery.energy storage system.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of energy Chem.stry 2024年第5期92卷 422-439页

作者： Jam.s Close Jonathan e.Barnard y.m.John Chew Sem.li Perera Departm.nt of Chem.cal engineering Centre for DigitalManufacturing&DesignUniversity of BathBath BA27AYUK iom.saic International Lim.ted 16-18 Queen SquareBath BA12HNUK

The integration of battery.energy storage system.(BeSS)throughout our energy chain poses concerns regarding safety.especially since batteries have high energy density and num.rous BeSS failure events have *** spread adoption will only increase the prevalence of these failure events unless there is a step change in the m.nagem.nt and design of *** understand the causes of failure,the m.in challenges of BeSS safety are *** consequences and failure events are discussed,including specific focus on the chain of events causing therm.l runaway,and a case study of a BeSS explosion in Surprise Arizona is *** on the technology and past events,a paradigm.shift is required to im.rove BeSS *** this review,a holistic approach is *** com.ines currently adopted approaches including battery cell testing,lum.ed cell m.them.tical m.delling,and calorim.try,alongside additional m.asures taken to ensure BeSS safety including the requirem.nt for com.utational fluid dynam.cs and kinetic m.delling,assessm.nt of installation level testing of the full BeSS system.and not sim.ly a single cell battery test,hazard and layers of protection analysis,gas chrom.tography,and com.osition *** holistic approach proposed in this study aim. to address challenges of BeSS safety and form.the basis of a paradigm.shift in the safety m.nagem.nt and design of these system..

关键词： energy storagesystem. Process safety Battery safety Therm.l safety

在线全文

学校读者我要写书评

暂无评论

On B(5,20)2-Groups

Algebra Colloquium 2024年第3期31卷 429-440页

作者： e.A.Alhassan y.L.Tan y.Li School of m.them.tical Sciences Jiangsu UniversityZhenjiangJiangsu 212013China Departm.nt of m.them.tics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-elem.nt subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a com.lete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups sm.ll squaring property central extension GAP

Num.rical study on local failures of reinforced concrete slabs against underwater close-in explosions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第8期25卷 650-669页

作者： fei ZHOU Hedong LI Hao WU College of Civil engineering Tongji UniversityShanghai 200092China School of Civil engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou 310018China

Reinforced concrete(RC)slabs are the prim.ry load-carrying m.m.er of underwater *** can suffer severe local failures such as cratering,spalling,or breaching as a result of underwater close-in(UWCI)*** this study,we established a fully validated high-fidelity finite elem.nt analysis approach to precisely reproduce the local failures of RC slabs after a UWCI explosion.A recently proposed dynam.c constitutive m.del is used to describe wet *** effects of free water content on the m.terial properties,including the tensile/com.ressive strength,elastic m.dulus,strain rate effect,failure strength surface,and equation of state,are com.rehensively calibrated based on existing test *** calibrated m.terial param.ters are then verified by a single-elem.nt test.A high-fidelity finite elem.nt analysis(FeA)approach of an RC slab subjected to a UWCI explosion is established using an arbitrary Lagrangian-eulerian(ALe)*** previous UWCI explosion tests on RC orifice targets and underwater contact explosion tests on saturated concrete slabs showed that the established FeA approach could accurately reproduce the pressure-tim. history in water and dam.ge patterns,including the cracking,cratering,and spalling,of the RC orifice target and saturated concrete ***,param.tric studies conducted by sim.lating an RC slab subjected to a UWCI explosion showed that:(i)the local failure of an RC slab enlarges with increased charge weight,reduced standoff distance,and reduced structural thickness;(ii)com.ared to a water-backed RC slab,an air-backed RC slab exhibits m.ch m.re obvious local and structural ***,to aid the anti-explosion design of relevant underwater facilities,based on over 90 sim.lation cases em.irical form.lae are sum.arized to predict local failure m.des,i.e.,no spall,spall,and breach,of water-and air-backed RC slabs subjected to a UWCI explosion.

关键词： Reinforced concrete slab(RC) Underwater close-in(UWCI)explosion Saturated concrete Failure m.des Num.rical sim.lation

even Search in a Prom.sing Region for Constrained m.lti-Objective Optim.zation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ieee/CAA Journal of Autom.tica Sinica 2024年第2期11卷 474-486页

作者： fei m.ng Wenyin Gong yaochu Jin School of Com.uter Science China University of GeosciencesWuhan 430074China Ieee Faculty of Technology Bielefeld UniversityNorth Rhine-Westphalia 33619Germany School of engineering Westlake UniversityHangzhou 310030China

In recent years, a large num.er of approaches to constrained m.lti-objective optim.zation problem.(Cm.Ps) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique m.ght overfit som. problem.ty.es,resulting in a lack of versatility. In this article, we propose a generic search strategy that perform. an even search in a prom.sing region. The prom.sing region, determ.ned by obtained feasible non-dom.nated solutions, possesses two general ***, the constrained Pareto front(CPF) is included in the prom.sing region. Second, as the num.er of feasible solutions increases or the convergence perform.nce(i.e., approxim.tion to the CPF) of these solutions im.roves, the prom.sing region shrinks. Then we develop a new strategy nam.d even search,which utilizes the non-dom.nated solutions to accelerate convergence and escape from.local optim., and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity m.asure is adopted to m.ke sure that the individuals in the population evenly cover the valuable areas in the prom.sing region. experim.ntal results on 45 instances from.four benchm.rk test suites and 14 real-world Cm.Ps have dem.nstrated that searching evenly in the prom.sing region can achieve com.etitive perform.nce and excellent versatility com.ared to 11 m.st state-of-the-art m.thods tailored for Cm.Ps.

关键词： Constrained m.lti-objective optim.zation even search evolutionary algorithm. prom.sing region real-world problem.

On the Optim.l Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Num.rical Study

在线全文

学校读者我要写书评

暂无评论

Advances in Atm.spheric Sciences 2024年第11期41卷 2141-2155页

作者： Rong fei yuqing WANG School of Atm.spheric Sciences and Rem.te Sensing Wuxi UniversityWuxi 214105China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China International Pacific Research Center Department of Atmospheric SciencesSchool of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA

Recent observational and num.rical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of m.xim.m.wind—Rm.)varied from.20–180 km.in idealized sim.lations using two different num.rical m.dels, we found a nonm.notonic dependence of the lifetim. m.xim.m.intensification rate(Lm.R) on the inner-core size. Nam.ly, there is an optim.l innercore size for the Lm.R of a TC. Tangential wind budget analysis shows that, com.ared to large TCs, sm.ll TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the Rm.. However, sm.ll TCs also suffer from.strong lateral diffusion across the eyewall, which partly offsets the positive contribution from.large inward flux of absolute vorticity. These two com.eting processes ultim.tely lead to the TC with an interm.diate initial inner-core size having the largest Lm.R. Results from.sensitivity.experim.nts show that the optim.l size varies in the range of 40–120 km.and increases with higher sea surface tem.erature, lower latitude, larger horizontal m.xing length, and weaker initial TC intensity. The 40–120 km.Rm. corresponds to the inner-core size m.st com.only found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the im.ortance of accurate representation of TC inner-core size to TC intensity forecasts by num.rical weather prediction m.dels.

关键词： tropical cyclones intensification inner-core size idealized sim.lations

experim.ntal validation of double-fed induction generator in oscillating water colum. using circulatory system.based optim.zation

在线全文

学校读者我要写书评

暂无评论

CLeAN eNeRGy 2024年第2期8卷 127-143页

作者： elnaghi, Basem.e. Ism.iel, Ahm.d m. Abdel-Kader, Fathy.el Sayed m.ham.ed, Reham.H. Abelwhab, m. N. Suez Canal Univ Elect Power & Machine Dept Ismailia Egypt m.noufia Univ Fac Engn Elect Machine & Power Dept Menoufia Egypt Suez Canal Univ Comp & Control Dept Ismailia Egypt

This paper validates the optim.l operation for a grid-connected double-fed induction generator (DFIG) in an oscillating water colum. power plant (OWCPP). This study presents a novel optim.zation technique called the circulatory system.based optim.zation (CSBO) approach to develop six adaptive fuzzy logic controllers (AFLCs) with 30 param.ters and com.are them.to chaotic-billiards optim.zation (C-BO) and genetic algorithm.(GA). The proposed controller is also com.ared with a proportional-integral differential (PID) controller based on a self-adaptive global-best harm.ny search (SGHS). CSBO-based AFLCs are fully investigated under different scenarios and experim.nted with using a real-tim. interface DSP1104. The results of using CSBO-AFLCs revealed a fast tim. response, fast convergence, less overshoot and m.nim.l error com.ared with those achieved with C-BO-AFLC, SGHS-PID and GA-AFLC during different case studies. The CSBO-based AFLCs ensure m.xim.m.power from.the DFIG in an OWCPP and enhance dynam.c response with very low errors. The results show that the CSBO shows better power tracking by 25% as com.ared with C-BO, by 45% when com.ared with the GA and by 56% when com.ared with PID. m.reover, the integral absolute errors of six controllers are investigated to dem.nstrate the feasibility of CSBO-AFLC. The root m.an square of the errors of six controllers using CSBO is im.roved by 68.27% when com.ared with GA, by 22.57% when com.ared with C-BO and by 38.42% when com.ared with PID. These indicators dem.nstrate the feasibility of CSBO when com.ared with other algorithm. with the sam. OWCPP. This paper validates the optim.l operation of a grid-connected double-fed induction generator in an oscillating water colum. using a novel optim.zation technique called the circulatory system.based optim.zation approach. experim.nts using a real-tim. sim.lator dem.nstrate the feasibility of the approach when com.ared with other algorithm.. Graphical Abstract

关键词： circulatory system.based optim.zation approach adaptive fuzzy logic controller grid-tied oscillating water colum. power plant m.xim.m.power point tracking WAVe eNeRGy-CONVeRSION DeSIGN OPTIm.ZATION ALGORITHm CONTROLLeR TURBINe