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Studies on the redox properties of the heteropolytungstosilicates substituted by transition elements

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Chinese Journal of Chemistry 1987年第1期5卷 30-39页

作者： ZHANG Bao-Jian qu lun-yu LIU Jing-Fu ZHAO Shi-Liang Department of Chemistry, Northeast Normal University, Changchun Department of Chemistry Northeast Normal University Changchun

The redox properties of the tri-heteropolytungstosilicates of transition elementsK_nSiZ（H2O）W11O39(Z = Mn2+, Fe3+, Co2+, Ni2+, Zn2+, Cd2+). In solution have been studied withpolarography and cyclic voltammetry as well as with ultraviolet spectroscopy and X-ray photoelectronspectroscopy. The order of the polarographic half-wave potentials (E1/2) of these heteropolyanions isas follows: Z = Ni2+>Co2+>Zn2+>Fe2+>Mn2+. We have found that the E1/3of heteropolyanionscould be correlated linearly with both the electronegativities X of the transition elements and the loga-rithm of the rate constants （log ke） of reaction of transition metal ions with hydrated electrons. Thereduction mechanism and effects of transition elements on the redox properties of the heteropolyanionshave been discussed.

关键词： Studies on the redox properties of the heteropolytungstosilicates substituted by transition elements

Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels

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Chinese Journal of Chemical Engineering 2024年第2期66卷 104-109页

作者： Rui yu Zhensheng Shen Yanan Liu Chengxiang Shi Juncong qu lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant *** propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation ***,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form *** then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction *** phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet *** work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil.

关键词： High-density fuel Biofuel Hydrogenation Alkylation Lignin Phenolics

Surface　Acidic　Properties　of　Loaded　Heteropoly　Acid　and　Preparation　of　Dimethylether　by　Catalyzed　Dehydration　of　Methyl　Alcohol

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Chemical Research in Chinese Universities 1997年第1期13卷 3-8页

作者： HUA Rui nian, WANG yuan hong, GONG Jian, ZU Wei and qu lun yu (Department of Chemistry, Northeast Normal University, Changchun, 130024) NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

The acidity and surface properties of H 4SiW 12 O 40 Ti(SO 4) 2 La 2O 3 HZSM 5(HTLH) were investigated by means of TEM, TPD and IR spectra. The activity and selectivity of the product as a catalyst for methanol to dimethylether were studied. The results show that there are Brnsted and Lewis acid sites in HTLH and that the total acidity is concerned with the conversion of methanol and the yield of dimethylether. The catalytic capacity of the acid at 453 K is the best. Keggin unit [SiW 12 O 40 ] 4- deposits on the external HZSM 5 surface only, and it can not permeate through the HZSM 5 pore system.

关键词： HZSM 5 12 Tungstosilicic acid Loading Acidity Dimethylether

quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： yu Du Weijie Chen yu Wang yue yu Kai Guo Gan qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S *** selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 *** work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi yu yu-ying Li yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Femtosecond laser-induced nanoparticle implantation into flexible substrate for sensitive and reusable microfluidics SERS detection

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International Journal of Extreme Manufacturing 2024年第4期6卷 262-274页

作者： Yongxiang Hu yu Zhou Guohu Luo Dege Li Minni qu State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People's Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816People's Republic of China Center for Advanced Electronic Materials and Devices School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People's Republic of China

Surface-enhanced Raman spectroscopy(SERS)microfluidic system,which enables rapid detection of chemical and biological analytes,offers an effective platform to monitor various food contaminants and disease *** efficacy of SERS microfluidic systems is greatly dependent on the sensitivity and reusability of SERS detection substrates to ensure repeated use for prolonged *** study proposed a novel process of femtosecond laser nanoparticle array(NPA)implantation to achieve homogeneous forward transfer of gold NPA on a flexible polymer film and accurately integrated it within microfluidic chips for SERS *** implanted Au-NPA strips show a remarkable electromagnetic field enhancement with the factor of 9×108 during SERS detection of malachite green(MG)solution,achieving a detection limit lower than 10 ppt,far better than most laser-prepared SERS ***,Au-NPA strips show excellent reusability after several physical and chemical cleaning,because of the robust embedment of laser-implanted NPA in flexible *** demonstrate the performance of Au-NPA,a SERS microfluidic system is built to monitor the online oxidation reaction between MG/NaClO reactants,which helps infer the reaction *** proposed method of nanoparticle implantation is more effective than the direct laser structuring *** provides better performance for SERS detection,robustness of detection,and substrate flexibility and has a wider range of applications for microfluidic systems without any negative impact.

关键词： femtosecond laser-induced transfer nanoparticle array surface-enhanced Raman spectrum microfluidic system

Shape estimation for a TPU-based multi-material 3D printed soft pneumatic actuator using deep learning models

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Science China(Technological Sciences) 2024年第5期67卷 1470-1481页

作者： HU yu TANG Wei qu Yang XU HuXiu KRAMARENKO yu.Elena ZOU Jun State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310027China Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou310027China Faculty of Physics Lomonosov Moscow State UniversityMoscow119991Russia Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of Sciences Moscow117393Russia

Real-time proprioception presents a significant challenge for soft robots due to their infinite degrees of freedom and intrinsic *** studies mostly focused on specific sensors and *** is still a lack of generalizable technologies for integrating soft sensing elements into soft actuators and mapping sensor signals to proprioception *** tackle this problem,we employed multi-material 3D printing technology to fabricate sensorized soft-bending actuators(SBAs)using plain and conductive thermoplastic polyurethane(TPU)*** designed various geometric shapes for the sensors and investigated their strain-resistive performance during *** address the nonlinear time-variant behavior of the sensors during dynamic modeling,we adopted a data-driven approach using different deep neural networks to learn the relationship between sensor signals and system states.A series of experiments in various actuation scenarios were conducted,and the results demonstrated the effectiveness of this *** sensing and shape prediction steps can run in real-time at a frequency of50 Hz on a consumer-level ***,a method is proposed to enhance the robustness of the learning models using data augmentation to handle unexpected sensor *** the methods are efficient,not only for in-plane 2D shape estimation but also for out-of-plane 3D shape *** aim of this study is to introduce a methodology for the proprioception of soft pneumatic actuators,including manufacturing and sensing modeling,that can be generalized to other soft robots.

关键词： shape estimation soft sensors and actuators 3D printing deep learning in robotics

Structure–performance relationship of Au nanoclusters in electrocatalysis:Metal core and ligand structure

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Carbon Energy 2024年第8期6卷 63-89页

作者： Bowen Li Lianmei Kang Yongfeng lun Jinli yu Shuqin Song Yi Wang The Key Lab of Low‐Carbon Chemistry&Energy Conservation of Guangdong Province PCFM LabSchool of Chemical Engineering and TechnologySchool of Materials Science and EngineeringSun Yat‐sen UniversityGuangzhouChina Department of Chemistry City University of Hong KongHong KongChina

Remarkable progress has characterized the field of electrocatalysis in recent decades,driven in part by an enhanced comprehension of catalyst structures and mechanisms at the *** precise metal nanoclusters,serving as exemplary models,significantly expand the range of accessible structures through diverse cores and ligands,creating an exceptional platform for the investigation of catalytic ***,ligand‐protected Au nanoclusters(NCs)with precisely defined core numbers offer a distinct advantage in elucidating the correlation between their specific structures and the reaction mechanisms in *** strategic modulation of the fine microstructures of Au NCs presents crucial opportunities for tailoring their electrocatalytic performance across various *** review delves into the profound structural effects of Au NC cores and ligands in electrocatalysis,elucidating their underlying mechanisms.A detailed exploration of the fundamentals of Au NCs,considering core and ligand structures,***,the interaction between the core and ligand structures of Au NCs and their impact on electrocatalytic performance in diverse reactions are *** the discourse,challenges and personal prospects are presented to guide the rational design of efficient electrocatalysts and advance electrocatalytic reactions.

关键词： Au nanoclusters core electrocatalytic performance ligand structures

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过氧铌杂多钨酸盐热分解动力学参数的测定

无机化学学报 2000年第5期16卷 815-820页

作者：马荣华刘春涛瞿伦玉陈玉齐齐哈尔大学化学化工学院齐齐哈尔161006 齐齐哈尔市环境监测中心站齐齐哈尔161005 东北师范大学化学学院长春130024

The thermal properties of two heteropoly complexes a- [ (C7H15) 4N]3H2[SiW11 (NbO2) O39] H2O and a-[ (C7H15)4N]4 [PW11 (NbO2). O39] H2O were studied by means of TG DTA and DSC. The activation energies and reaction ord... 详细信息

关键词：过氧铌杂多配合物活化能反应级数热分解