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Reversible isomerization of donor-acceptor Stenhouse adduct derivatives in water through dendritic confinement

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Science China Chemistry 2024年第5期67卷 1636-1646页

作者： Jiaxing Zhang Qingyun Zhao Xinyan Su Afang Zhang wen Li International Joint Laboratory of Biomimetic and Smart Polymers School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

Modulating reversible isomerization of hydrophobic dyes in aqueous solutions is greatly desired. Here we report on reversible isomerization of solvatochromic donor-acceptor Stenhouse adducts(DASAs) in water through the confinement from dendritic oligoethylene glycols(OEGs). Dendronization of DASAs with dendritic OEGs affords them characteristic thermoresponsiveness. These dendronized DASAs spontaneously isomerize in water from hydrophobic linear state into hydrophilic cyclic state at room temperature due to the strong hydration. However, hydrophobic microenvironment through thermally dehydration and collapse of the dendritic OEGs at elevated temperatures confines hydration of the DASA moieties and mediates their interactions with the collapsed hydrophobic OEG domains, affording their isomerization recovery in water efficiently from the hydrophilic cyclic state into the hydrophobic linear state. The confinement-mediated reversible isomerization of DASA moieties in water can be repeated through alternative photo-irradiation and thermal dehydrations, exhibiting excellent fatigue resistance.

关键词： dendrimers donor-acceptor Stenhouse adducts isomerization confinement thermoresponsiveness

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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Engineering 2024年第6期37卷 230-245页

作者： Chang-Kai wen wen Ren Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li Zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

Magnetic and luminescent properties of bifunctional composite Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+)

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Journal of Rare Earths 2024年第8期42卷 1568-1576,I0006页

作者： Zhiqi Liang Zhili Zhang Liu Li wen Xu Decai Li School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing100044China State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China

As a kind of non-destructive testing method,magnetic particle inspection is widely used in the fields of aviation and high-speed *** properties of magnetic fluorescent bifunctional composites,such as fluorescence intensity and magnetic properties,have increasing demands in magnetic particle *** earth compounds offer potential as novel materials for fluorescent magnetic bifunctional composites due to their excellent optical properties and extremely narrow emission *** this work,the rare earth fluorescent material Y_(2)O_(2)S:Eu^(3+) was synthesized by solid-state reaction ***_(3)O_(4)nanoparticles prepared by hydrothermal method were uniformly coated on the Y_(2)O_(2)S:Eu^(3+) particles through physical adsorption of *** obtained Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) exhibits dark red color under the ultraviolet *** additio n,X-ray diffractio n,morphology,photoluminescence and hyste resis loop of Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) were *** luminescence mechanism of Y_(2)O_(2)S:Eu^(3+) is described in detail Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) displays good paramagnetism and has a good controllability under a magnetic *** magnetic particle inspection of Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) was performed using a 4-pole electromagnet and a test piece *** magnetic fluorescent bifunctional composite presented in this work can be applied for non-destructive testing.

关键词： Bifunctional material Fe_(3)O_(4) Y_(2)O_(2)S:Eu^(3+) Luminescence Solid-state reaction Rare earths

Unmanned Aerial Vehicle Inspection Routing and Scheduling for Engineering Management

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Engineering 2024年第5期36卷 223-239页

作者： Lu Zhen Zhiyuan Yang Gilbert Laporte wen Yi Tianyi Fan School of Management Shanghai UniversityShanghai 200444China Department of Decision Sciences HEC MontréalMontréalQC H3T 2A7Canada School of Management University of BathBath BA27AYUK Department of Building and Real Estate The Hong Kong Polytechnic UniversityHong Kong 999077China

Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based *** engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection *** on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring *** tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging *** comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale *** overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our *** numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale *** experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency.

关键词： Engineering management Unmanned aerial vehicle Inspection routing and scheduling optimization Mixed-integer linear programming model Variable neighborhood search metaheuristic

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu Zhang Yi Zhang wen-hao Tian Yan Li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution

Solvothermal synthesis and adsorption performance of layered boehmite using aluminum chloride and high-alumina fly ash

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Chinese Journal of Chemical Engineering 2024年第6期70卷 280-290页

作者： Jing wen Ruirui Yuan Tao Jiang Tangxia Yu Yufan Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China Liaoning Key Laboratory for Metallurgical Sensor and Technology Shenyang 110819China

High alumina fly ash(FAHAl)is a kind of bulk solid waste unique to China,whose availability of high-value aluminum and the threat to the environment makes its high-value utilization *** this work,the alumina containing leaching solution obtained from Na_(2)CO_(3) roasting and HCl leaching of FAHAl was used as the mother liquor to prepare layered boehmite in *** preparation process with AlCl_(3) as the raw material was also *** formation process and mechanism of boehmite,the choice of solvent,along with the adsorption capability of Congo red were analyzed by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,Brunauer-Emmett-Teller method and adsorption *** showed that during the preparation of layered boehmite,the precursor Al(OH)_(3) from the reaction of Al^(3+) and OH-is transformed into boehmiteγ-*** existence of ethanol is beneficial to regulate and promote the growth of boehmite crystal *** water and ethanol are mixed with a volume ratio of 2:1 and used as the solvent,the maximum specific surface area of the boehmite is obtained at 135.7 m^(2)·g^(-1),and 99.16%of Congo red can be absorbed after 10 min when AlCl3 is used as a raw *** purified leaching solution is used as the mother liquid,the crystallinity of boehmite decreases slightly when the pH value decreases from 12.5 to *** pH is 11,the removal efficiency of Congo red reaches a maximum of 72.25%.This process not only achieves the extraction of aluminum and high-value utilization of FAHAl but also provides a thought to prepare layered boehmite with adsorption properties.

关键词： High-alumina fly ash Layered boehmite In-situ preparation Solvothermal synthesis Adsorption High-value utilization

Interplay between geometric and electronic structures of Pt entities over TiO_(2) for CO oxidation

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Science China Chemistry 2024年第2期67卷 705-714页

作者： Xixiong Zhang wen Shi Shaobo Han Yong Li wenjie Shen School of Chemistry Dalian University of TechnologyDalian116024China State Key Laboratory of Catalysis Dalian Institution of Chemical PhysicsChinese Academy of SciencesDalian116023China

Monodispersed Pt colloids with a mean size of 2 nm were deposited uniformly on the {110} facets of a rod-shaped rutile TiO_(2),forming a well-defined Pt/TiO_(2) *** treatment of this precursor at elevated temperatures re-dispersed the Pt particles into clusters and ***-calcination at 673 K partially oxidized the Pt particle surface,while calcination at 773 K yielded Pt Oxclusters of 1.6 nm in 7–8 atomic *** calcination at 873 K formed a mixture of raft-like PtO_(x) clusters(1.6 nm,1–2 atomic layers) and cationic *** tested for CO oxidation at 373 K,the Pt particles showed a higher activity than the Pt Oxclusters,whereas the cationic single-atoms were much less *** H_(2)-reduction at 473 K converted the partially oxidized Pt particles into the metallic species,but they were encapsulated by TiO_(2)–xoverlayers because of the strong metal–support interactions,which decreased the activity dramatically.H_(2)-reduction of the PtO_(x) clusters at473 K enhanced the fraction of metallic Pt species without changing the size and geometry,and promoted the activity substantially.H_(2)-treatment of Pt single-atoms at 473 K increased the activity only moderately because most Pt species still kept at cationic *** results straightforwardly differentiated the catalytic behavior of Pt particles,clusters and single-atoms at the same metal loading and over the same TiO_(2) support,and further demonstrated that the electronic structures of Pt entities played a decisive role in the catalytic oxidation,in addition to the specified sizes.

关键词： Pt/TiO_(2)catalyst size effect Pt clusters active sites electronic structures CO oxidation

Air target intention recognition and causal effect analysis combining uncertainty information reasoning and potential outcome framework

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Chinese Journal of Aeronautics 2024年第1期37卷 287-299页

作者： Yu ZHANG Fanghui HUANG Xinyang DENG Mingda LI wen JIANG School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

Recognizing target intent is crucial for making decisions on the ***,the imperfect and ambiguous character of battlefield situations challenges the validity and causation analysis of classical intent recognition *** with the challenge,a target intention causal analysis paradigm is proposed by combining with an Intervention Retrieval(IR)model and a Hybrid Intention Recognition(HIR)*** target data acquired by the sensors are modelled as Basic Probability Assignments(BPAs)based on evidence theory to create uncertain ***,the HIR model is utilized to recognize intent for a tested sample from uncertain ***,the intervention operator under the evidence structure is utilized to perform attribute intervention on the tested *** retrieval is performed in the sample database based on the IR model to generate the intention distribution of the pseudo-intervention samples to analyze the causal effects of individual sample *** simulation results demonstrate that our framework successfully identifies the target intention under the evidence structure and goes further to analyze the causal impact of sample attributes on the target intention.

关键词： Causal effect analysis Hybrid intention recognition Intervention retrieval Target intention Uncertainty reasoning

Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

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Journal of Environmental Sciences 2024年第3期137卷 287-301页

作者： Yongguo Dai Yu Peng wen Hu Yi Liu Hui Wang Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Department of Pharmacy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Amoxicillin,a widely used antibiotic in human and veterinary pharmaceuticals,is now considered as an“emerging contaminant”because it exists widespreadly in the environment and brings a series of adverse ***,systematic studies about the developmental toxicity of amoxicillin are still *** explored the potential effects of amoxicillin exposure on pregnancy outcomes,maternal/fetal serum phenotypes,and fetal multiple organ development in mice,at different doses(75,150,300 mg/(kg·day))during late-pregnancy,or at a dose of 300 mg/(kg·day)during different stages(mid-/latepregnancy)and courses(single-/multi-course).Results showed that prenatal amoxicillin exposure(PAmE)had no significant infuence on the body weights of dams,but it could inhibit the physical development and reduce the survival rate of fetuses,especially during the ***,PAmE altered multiple maternal/fetal serum phenotypes,especially in *** multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis,long bone/cartilage and hippocampal development,and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis,and the order of severity might be gonad(testis,ovary)>liver>*** analysis found that PAmE-induced multiorgan developmental and functional alterations had differences in stages,courses and fetal gender,and the most obvious changes might be in high-dose,late-pregnancy and multicourse,but there was no typical rule of a dose-response *** conclusion,this study confirmed that PAmE could cause abnormal development and multi-organ function alterations,which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

关键词： Amoxicillin Prenatal exposure Fetal development Organ function Developmental toxicity