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HVSR analysis of pum.ce sands for sedim.nt depth characterization:A case study for Guadalajara,m.xico

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandro Ram.rez-Gaytan Adolfo Preciado Christian R.Escudero Departam.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Departam.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Departam.nto del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)m.thodology is used here to characterize pum.ce soils and to im.ge the three-dim.nsional surface geom.try of Guadalajara,*** to other latin Am.rican cities,Guadalajara is exposed to high seism.c risk,with the particularity of being the largest urban settlem.nt in latin Am.rica built on pum.ce *** has not yet been tested to characterize subsoil depths in pum.ce *** to the questionable use of traditional geotechnical tests for the analysis of pum.ce soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak am.litude(A0)are used to constrain the depth of the m.jor im.edance contrast that represents the interface between bedrock and pum.ce *** were com.ared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estim.ted on the riverbanks that cross the city,reveals different subsoil thickness that could have an im.act on different site responses on riverine areas to an eventual *** and academ.c efforts are com.ined in this work to characterize depth sedim.nts,an im.ortant param.ter that im.acts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pum.ce soil characterization

m.crostructure hom.geneity and m.chanical properties of laser-arc hybrid welded AZ31B m.gnesium.alloy

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Journal of m.gnesium.and Alloys 2024年第5期12卷 1986-1995页

作者： Yongkang Gao Kangda Hao Lianyong Xu Yongdian Han Lei Zhao Wenjing ren Hongyang Jing School of m.terials Science and Engineering Tianjin UniversityTianjin 300350PR China Tianjin Key laboratory of Advanced Joining Technology Tianjin 300350PR China

laser-arc hybrid welding of AZ31B m.gnesium.alloy was carried out,the effects of welding param.ters on weld form.tion,m.crostructure hom.geneity and m.chanical properties were *** results showed that laser-arc hybrid welding was beneficial to im.rove the weld form.tion of m.gnesium.alloy by inhibiting the defect of undercut and *** weld m.crostructure was m.inly colum.ar grains neighboring the fusion line and equiaxed grains at the weld *** was interesting that the grain size at the upper arc zone was sm.ller than that at the lower laser zone,with the difference m.inly affected by laser power rather than welding current and welding *** welding param.ters were optim.zed as laser power of 3.5 kW,welding current of 100 A and welding speed of 1.5 m.*** this case,the weld was free of undercut and pores,and the tensile strength and elongation rate reached 252 m.a and 11.2%,***,the m.crostructure hom.geneity was illustrated according to the heat distribution,and the evolution law of tensile properties was discussed basing on the weld form.tion and m.crostructure characteristics.

关键词： m.gnesium.alloy laser-arc hybrid welding m.crostructure hom.geneity m.chanical properties

Highly active organocatalyst from.a trivalent phosphazenium.salt for ring-opening copolym.rization of epoxides and cyclic anhydrides enhanced by hydrogen bonding interactions

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Science China Chem.stry 2024年第9期67卷 3111-3120页

作者： Chunhuan Jiang Junqi Wang Xiaoyu Liu Xiaoxia You Ronglin Zhong Chuanli ren Zhibo Li Key laboratory of Biobased Polym.r m.terials Shandong Provincial Education DepartmentCollege of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Chem.cal Engineering Qingdao University of Science and TechnologyQingdao 266042China laboratory of Theoretical and Com.utational Chem.stry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130012China

It is highly desirable to develop sim.le organocatalysts for the controlled ring-opening alternating copolym.rization(ROAC)of epoxides and cyclic anhydrides,leading to high m.lecular weight ***,a phosphazenium.salt,nam.ly tri[tris(dim.thylam.no)phosphoranylidenam.no]phosphonium.chloride(P_(4)^(+)Cl^(-)),is developed as a catalyst for the ROAC of epoxides and cyclic ***,the com.ination of P_(4)^(+)Cl^(-)with a protonic initiator,such as 1,4-benzenedim.thanol(BDm.exhibited high efficiency in the copolym.rization of propylene oxide(PO)and phthalic anhydride(PA).This led to the production of polyester with an exceptional high m.lecular weight(m.n)of up to 126 k Da,which represented a rare exam.le of poly(PO-alt-PA)with m.surpassing 100 k *** that the core P atom.is trivalent status and the tris[tris(dim.thylam.no)]phosphoranyl group will share one proton in the P_(4)^(+)Cl^(-)*** com.ined with protonic species,the P_(4)^(+)Cl^(-)will not only serve as a proton acceptor but also as a hydrogen bonding donor for the cyclic ***,it was assum.d that the P_(4)^(+)plus proton served dual role in m.m.c of base/urea pair to effectively catalyze ROAC,which was supported by density functional theory(DFT)calculations.

关键词： ring-opening copolym.rization organocatalyst epoxides cyclic anhydrides phosphazenium.salt

Application of the CatBoost m.del for Stirred Reactor State m.nitoring Based on Vibration Signals

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Com.uter m.deling in Engineering & Sciences 2024年第7期140卷 647-663页

作者： Xukai ren Huanwei Yu Xianfeng Chen Yantong Tang Guobiao Wang Xiyong Du School of m.chanical Engineering Tianjin UniversityTianjin300354China Quality Departm.nt Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071China

Stirred reactors are key equipm.nt in production,and unpredictable failures will result in significant econom.c losses and safety ***,it is necessary to m.nitor its health *** achieve this goal,in this study,five states of the stirred reactor were firstly preset:norm.l,shaft bending,blade eccentricity,bearing wear,and bolt *** signals along x,y and z axes were collected and analyzed in both the tim. dom.in and frequency ***,93 statistical features were extracted and evaluated by ReliefF,m.xim.l Inform.tion Coefficient(m.C)and *** above evaluation results were then fused by D-S evidence theory to extract the final 16 features that are m.st relevant to the state of the stirred ***,the CatBoost algorithm.was introduced to establish the stirred reactor health m.nitoring *** validation results showed that the m.del achieves 100%accuracy in detecting the fault/norm.l state of the stirred reactor and 98%accuracy in diagnosing the type of fault.

关键词： Stirred reactor fault diagnosis vibration signal CatBoost

Audio-Text m.ltim.dal Speech Recognition via Dual-Tower Architecture for m.ndarin Air Traffic Control Com.unications

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Com.uters, m.terials & Continua 2024年第3期78卷 3215-3245页

作者： Shuting Ge Jin ren Yihua Shi Yujun Zhang Shunzhi Yang Jinfeng Yang School of Com.uter Science and Software Engineering University of Science and Technology LiaoningAnshan114051China Institute of Applied Artificial Intelligence of the Guangdong-Hong Kong-m.cao Greater Bay Area Shenzhen Polytechnic UniversityShenzhen518055China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518055China Industrial Training Centre Shenzhen Polytechnic UniversityShenzhen518055China

In air traffic control com.unications (ATCC), m.sunderstandings between pilots and controllers could result in fatal aviation accidents. Fortunately, advanced autom.tic speech recognition technology has em.rged as a prom.sing m.ans of preventing m.scom.unications and enhancing aviation safety. However, m.st existing speech recognition m.thods m.rely incorporate external language m.dels on the decoder side, leading to insufficient sem.ntic alignm.nt between speech and text m.dalities during the encoding phase. Furtherm.re, it is challenging to m.del acoustic context dependencies over long distances due to the longer speech sequences than text, especially for the extended ATCC data. To address these issues, we propose a speech-text m.ltim.dal dual-tower architecture for speech recognition. It em.loys cross-m.dal interactions to achieve close sem.ntic alignm.nt during the encoding stage and strengthen its capabilities in m.deling auditory long-distance context dependencies. In addition, a two-stage training strategy is elaborately devised to derive sem.ntics-aware acoustic representations effectively. The first stage focuses on pre-training the speech-text m.ltim.dal encoding m.dule to enhance inter-m.dal sem.ntic alignm.nt and aural long-distance context dependencies. The second stage fine-tunes the entire network to bridge the input m.dality variation gap between the training and inference phases and boost generalization perform.nce. Extensive experim.nts dem.nstrate the effectiveness of the proposed speech-text m.ltim.dal speech recognition m.thod on the ATCC and AISHELL-1 datasets. It reduces the character error rate to 6.54% and 8.73%, respectively, and exhibits substantial perform.nce gains of 28.76% and 23.82% com.ared with the best baseline m.del. The case studies indicate that the obtained sem.ntics-aware acoustic representations aid in accurately recognizing term. with sim.lar pronunciations but distinctive sem.ntics. The research provides a novel m.deling pa

关键词： Speech-text m.ltim.dal autom.tic speech recognition sem.ntic alignm.nt air traffic control com.unications dual-tower architecture

Effects of arbuscular m.corrhizal fungi on carbon assim.lation and ecological stoichiom.try of m.ize under com.ined abiotic stresses

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Journal of Plant Ecology 2024年第2期17卷 74-88页

作者： Qiong Ran Songlin Zhang m.ham.ad Arif Xueting Yin Shanshan Chen Guangqian ren School of m.nagem.nt Chongqing University of TechnologyChongqing 400054China Key laboratory of Reservoir Aquatic Environm.nt Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Key laboratory of Eco-environm.nts in Three Gorges Reservoir Region(m.nistry of Education) State Cultivation Base of Eco-agriculture for Southwest Mountainous LandSchool of Life SciencesSouthwest UniversityChongqing 400715China Institute of Environm.nt and Ecology Academy of Environmental Health and Ecological SecuritySchool of the Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China

Arbuscular m.corrhizal fungi(Am.)enhance plant tolerance to abiotic stresses like salinity and im.rove crop ***,their effects are variable,and the underlying cause of such variation rem.ins largely *** study aim.d to assess how drought m.difed the effect of Am. on plant resistance to high calcium.saline stress.A pot experim.nt was perform.d to exam.ne how Am. inoculation affects the growth,photosynthetic activity,nutrient uptake and carbon(C),nitrogen(N)and phosphorus(P)stoichiom.tric ratio(C:N:P)of m.ize under high calcium.stress and contrasting water *** results showed that high calcium.stress signifcantly reduced m.corrhizal colonization,biom.ss accum.lation,C assim.lation rate and C:N stoichiom.tric ratio in plant ***,the adverse effects of calcium.stress on photosynthesis were exacerbated under *** inoculation profoundly alleviated such reductions under drought and saline ***,it barely affected m.ize perform.nce when subjected to calcium.stress under well-watered ***,watering changed Am. im.act on nutrient allocation in plant *** well-watered conditions,Am. stim.lated P accum.lation in roots and plant growth,but did not induce leaf P accum.lation proportional to C and N,resulting in increased leaf C:P and N:P ratios under high calcium.*** contrast,Am. decreased N content and the N:P ratio in leaves under ***,Am. inoculation im.roved m.ize resistance to calcium.salt stress through enhanced photosynthesis and m.dulation of nutrient stoichiom.try,particularly under water defcit *** results highlighted the regulatory role of Am. in carbon assim.lation and nutrient hom.ostasis under com.ound stresses,and provide signifcant guidance on the im.rovem.nt of crop yield in saline and arid regions.

关键词： arbuscular m.corrhizal fungi com.ound abiotic stresses C:N:P stoichiom.try induced system.c resistance calcium.salt stress

Coupled CFD-DEm.Num.rical Sim.lation of the Interaction of a Flow-Transported Rag with a Solid Cylinder

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Fluid Dynam.cs & m.terials Processing 2024年第7期20卷 1593-1609页

作者： Yun ren Lianzheng Zhao Xiaofan m. Shuihua Zheng Youdong Yang Zhijiang College Zhejiang University of TechnologyShaoxing312030China College of m.chanical Engineering Zhejiang University of TechnologyHangzhou310032China

A coupled Com.utational Fluid Dynam.cs-Discrete Elem.nt m.thod(CFD-DEm.approach is used to calculate the interaction of a flexible rag transported by a fluid current with a fixed solid *** specifically a hybrid Eulerian-lagrangian approach is used with the rag being m.deled as a set of interconnected *** influence of various param.ters is considered,nam.ly the inlet velocity(1.5,2.0,and 2.5 m.s,respectively),the angle form.d by the initially straight rag with the flow direction(45°,60°and 90°,respectively),and the inlet position(90,100,and 110 m.,respectively).The results show that the flow rate has a significant im.act on the perm.ability of the *** higher the flow rate,the higher the perm.ability and the rag speed *** angle has a m.nor effect on rag perm.ability,with 45°being the m.st favorable angle for *** inlet position has a sm.ll im.act on rag perm.ability,while reducing the initial distance between the rag an the cylinder m.kes it easier for rags to pass through.

关键词： Rag flow around cylinder flow characteristics num.rical sim.lation

Crystallinity-defect m.tching relationship of g-C_(3)N_(4): Experim.ntal and theoretical perspectives

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Green Energy & Environm.nt 2024年第4期9卷 623-658页

作者： Yuhan Li Ziteng ren Zhengjiang He Ping Ouyang Youyu Duan Wendong Zhang Kangle Lv Fan Dong Engineering Research Center for Waste Oil Recovery Technology and Equipm.nt Ministry of EducationChongqing Key Laboratory of Catalysis and New Environmental MaterialsChongqing Technology and Business UniversityChongqing400067China Nanchang Institute of Technology Nanchang33044China Key laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Com.ission College of Resources and Environmental ScienceSouth-Central Minzu UniversityWuhan430074China College of Physics and Center of Quantum.m.terials and Devices Chongqing UniversityChongqing401331China Chongqing Key laboratory of Green Synthesis and Application Chongqing Normal UniversityChongqing401331China

Good crystallinity can reduce the charge recom.ination centers caused by defects,whilst structures with strong polycondensation have high charge m.bility,leading to m.re charge transfer to the m.terial surface for *** effort has been put into the preparation of a highly efficient g-C_(3)N_(4) with defects to im.rove its application potential under the prem.se in high ***,this review paper em.hasizes the im.ortance to balance the defect and crystallinity of g-C_(3)N_(4).In addition,detailed discussion on the relationship between defects and activity of g-C_(3)N_(4) was carried out based on its applications in environm.ntal purification(e.g.,VOCs oxidation,NO_(x) oxidation,H_(2)O_(2) evolution,sterilization,pesticide oxidation)and energy conversion(H_(2) evolution,N_(2) fixation and CO_(2) reduction).lastly,the challenge in developing m.re efficient defective g-C_(3)N_(4) photocatalytic m.terials is sum.arized.

关键词： Photocatalysis Defect G-C_(3)N_(4) Crystallinity Application

Pyridine-regulated Sb@InSbS_(3)ultrafine nanoplates as high-capacity and long-cycle anodes for sodium.ion batteries

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Rare m.tals 2024年第5期43卷 2080-2092页

作者： Jia-Ying ren Xiang-Lin Yu Chang-m.ao Chen Xin-Yu Hu Ting Yang m.ng Zhang College of m.terials Science and Engineering and College of Science Central South University of Forestry and TechnologyChangsha 410004China College of Sem.conductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China

Sb-based m.terials exhibit considerable potential for sodium.ion storage owing to their high theoretica ***,the bulk properties of Sb-based m.terials always result in poor cycling and rate *** overcom. these issues,pyridine-regulated Sb@InSbS_(3)ultrafine nanoplates loaded on reduced graphene oxides(Sb@InSbS_(3)@rGO)were designed and *** the synthesis process,pyridine was initially adopted to coordinate with In^(3+),and uniform.y dispersed In_(2)S_(3)ultrafine nanoplates on reduced graphene oxide were generated after ***,partial In^(3+)was exchanged with Sb^(3+),and Sb@InSbS_(3)@rGO was obtained by using the subsequent annealing *** unique structure of Sb@InSbS_(3)@rGO effectively shortened the transfer path of sodium.ions and electrons and provided a high *** the anode in sodium.ion batteries,the Sb@InSbS_(3)@rGO electrode dem.nstrated a significantly higher reversible capacity better stability(445 m.Ah·g^(-1)at 0.1 A·g^(-1)after 200 cycles and 212 m.h·g^(-1)at 2 A·g^(-1)after 1200 cycles),and superior rate(210 m.h·g^(-1)at 6.4 A·g^(-1))than the electrode without pyridine(355 m.h·g-1at 0.1 A·g-1after 55 cycles and 109 m.h·g^(-1)at 2 A·g^(-1)after 770 cycles)Furtherm.re,full cells were assem.led by using the Sb@InSbS_(3)@rGO as anode and Na_(3)V_(2)(PO_(4))_(3)as cathode which dem.nstrated good cycling and rate perform.nces and exhibited prom.sing application *** results indicate that adjusting the m.crostructure of electrode m.terials through coordination balance is A·good strategy for obtaining high-capacity,high-rate,and longcycle sodium.storage perform.nces.

关键词： Sodium.ion battery Sb-based anode m.terial Pyridine coordination Reduced size nanostructure Half/full cell