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Insight into the large electro-strain in bismuth sodium titanate-based relaxor ferroelectrics:From fundamentals to regulation methods

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Journal of Materials Science & Technology 2023年第19期150卷 27-48页

作者： Xiaojun Wu Lanji Wen chao Wu Xiang lv Jie Yin Jiagang Wu College of Materials Science and Engineering Sichuan University610064PR China

Due to the demand for environmental protection,developing eco-friendly piezoelectric applica-tions/materials is an inevitable *** market share of lead-free materials is growing steadily every *** typical lead-free systems,Bi_(0.5)Na_(0.5)TiO_(3)(BNT)has attracted wide attention due to its supe-rior strain property(e.g.,dynamic piezoelectric coefficient d33*of most modified-BNT ceramics exceeds 600 pm/V,which is higher than commercial soft PZT ceramics PIC151).The excellent strain performance in BNT-based materials is thought to arise from the relaxor-ferroelectric transition,and currently,the mainstream strain regulation method is chemical *** far,amounts of effective dopants have been investigated,while the intrinsic strain regulation mechanism is still ambiguous(e.g.,how do dopants work?).Therefore,we review the intrinsic strain regulation mechanism,and strain origination and reg-ulation methods are also investigated to comprehend the regulation ***,the strain origination and regulation mechanism are investigated from different dimensions(e.g.,macro perspective and micro perspective),which is vacant in previous *** the macro view,the particular tai-lored relaxor-ferroelectric crossover is the critical key for the giant electro-strain,while from the micro view,the electro-strain is dominated by the cracked ferroelectric order and relaxor-ferroelectric transi-tion,resulting from the broken Bi-O bonds due to the local field *** the strain origination and regulation mechanism of BNT-based ceramics is of great importance to exclude the blind researching mode and rationally design the experimental scheme.

关键词： Strain origin Bi_(0.5)Na_(0.5)TiO_(3)(BNT) Strain regulation

A Review on Recent Development of Cooling Technologies for Photovoltaic Modules

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Journal of Thermal Science 2020年第6期29卷 1410-1430页

作者： ZHANG Chunxiao SHEN chao WEI Shen WANG Yuan lv Guoquan SUN Cheng Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologySchool of ArchitectureHarbin Institute of TechnologyHarbin 150090China The Bartlett School of Construction and Project Management University College London(UCL)London WC1E 7HBUK

When converting solar energy to electricity,a big proportion of energy is not converted for electricity but for heating PV cells,resulting in increased cell temperature and reduced electrical *** cooling technologies have been developed and used for PV modules to lower cell temperature and boost electric energy ***,little crucial review work was proposed to comment cooling technologies for PV ***,this paper has provided a thorough review of the up-to-date development of existing cooling technologies for PV modules,and given appropriate comments,comparisons and *** to the ways or principles of cooling,existing cooling technologies have been classified as fluid medium cooling(air cooling,water cooling and nanofluids cooling),optimizing structural configuration cooling and phase change materials *** influential factors and sub-methods were collected from the review work,and their contributions and impact have been discussed to guide future *** most cooling technologies reviewed in this paper are matured,there are still problems need to be solved,such as the choice of cooling fluid and its usability for specific regions,the fouling accumulation and cleaning of enhanced heat exchangers with complex structures,the balance between cooling cost and net efficiency of PV modules,the cooling of circulating water in tropical areas and the freezing of circulating water in cold *** be advocated,due to efficient heat transfer and spectral filter characters,nanofluids can promote the effective matching of solar energy at both spectral and spatial scales to achieve orderly energy utilization.

关键词： solar energy PV modules cooling technologies nanoparticles phase change materials

Ferrosilicon alloy granules prepared through centrifugal granulation process

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Journal of Iron and Steel Research International 2020年第11期27卷 1247-1258页

作者： Wen-chao He Xue-wei lv Zhi-ming Yan Gang-qiang Fan Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

A novel granulation process that involved the use of a rotary multi-nozzles cup atomizer and water cooling was proposed for ferroalloy *** effects of rotating speed and nozzle diameter on the properties of FeSi75 alloy(containing 75 wt.%Si)granules were *** indicated that median granule diameter decreased as rotating speed in creased,and initially increased and then decreased as nozzle diameter in *** optimal conditi ons for the gra nulation of FeSi75 alloy were a rotating speed of 150 r/min and nozzle diameter of 10 or 12 *** phase composition,micromorphology,and elemental distribution of the FeSi75 alloy granules were also studied by X-ray diffraction,scanning electron microscopy,and energy-dispersive X-ray *** order to provide guidance for the layout and water depth of the tank,the solidification behavior of ferrosilicon alloy droplet was numerically studied.A simplified model was established to elucidate the traveling trajectory and heat transfer of alloy droplet in air and cooling water during the atomization *** solidification time of droplet with different thicknesses of solidification layer increased with the in crease in alloy droplet diameter.

关键词： FeSi75 alloy Rotary multi-nozzles cup atomizer Size distribution Microstructural analysis Solidification behavior

Ligand-Enabled Ni-Catalyzed Enantioselective Hydroarylation of Styrenes and 1,3-Dienes with Arylboronic Acids

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CCS Chemistry 2019年第4期1卷 328-334页

作者： Xin-Yang lv chao Fan Li-Jun Xiao Jian-Hua Xie qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

We report an enantioselective hydroarylation reaction of styrenes and 1,3-dienes with arylboronic acids catalyzed by nickel complexes bearing chiral spiro amino phosphine *** reaction serves as an efficient,straightf orward,and mild method for the preparation of enantio enriched 1,1-diarylalkanes,which are important building blocks for the synthesis of many biologically active *** redox neutral reaction uses only catalytic amounts of the reagents and is,therefore,atom economical and environmentally benign.

关键词： nickel catalyst enantioselective hydroarylation alkene organoboron chiral spiro aminophosphine

A framework for the responsible reform of the 14-day rule in human embryo research

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Protein & Cell 2022年第8期13卷 552-558页

作者： Yaojin Peng Jianwei lv Zhenyu Xiao Lulu Ding qi Zhou State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China University of the Chinese Academy of Sciences Beijing 100049China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

Ever since the world's first"test-tube"baby was bom in 1978,the use of human embryos in research has become highly controversial ethically and thus created a significant challenge for jurisdictions,especially in Europ... 详细信息

关键词： framework rule created

Experimental study on the membrane distillation of highly mineralized mine water

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International Journal of Coal Science & Technology 2021年第5期8卷 1025-1033页

作者： Ji qi Jiafeng lv Wei Bian Jingfeng Li Shuqin Liu School of Chemical and Environmental Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of Water Resource Protection and Utilization in Coal Mining China Energy Investment CorporationBeijing 100011China

Membrane distillation(MD)is a promising membrane separation technique used to treat industrial *** coupled with cheap heat sources,MD has significant economic ***,MD can be combined with solar energy to realize the large-scale and low-cost treatment of highly mineralized mine water in the western coalproducing region of *** this study,highly mineralized mine water from the Ningdong area of China was subjected to vacuum MD(VMD)using polyvinylidene fluoride hollow-fiber *** optimal operation parameters of VMD were determined by response surface ***,the feasibility of VMD for treating highly mineralized mine water was *** fouling behavior observed during VMD was further investigated by scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS).Under the optimal parameters(pressure=-0.08 MPa,temperature=70℃,and feed flow rate=1.5 L/min),the maximum membrane flux was 8.85 kg/(m^(2) h),and the desalination rate was 99.7%.Membrane fouling could be divided into three stages:membrane wetting,crystallization,and fouling layer *** cleaning restored the flux and salt rejection rate to 94%and 97%of the initial values,respectively;however,the cleaning interval and cleaning efficiency decreased as the VMD run time ***-EDS analysis revealed that the reduction in flux was caused by the precipitation of CaCO_(3).The findings also demonstrated that the membrane wetting could be attributed to the formation of NaCl on the cross section and outer surface of the ***,the results confirm the feasibility of MD for treating mine water and provide meaningful guidance for the industrial application of MD.

关键词： Mine water Membrane distillation Operating parameters Membrane fouling

Modified Multifidelity Surrogate Model Based on Radial Basis Function with Adaptive Scale Factor

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 109-123页

作者： Yin Liu Shuo Wang qi Zhou Liye lv Wei Sun Xueguan Song School of Mechanical Engineering Dalian University of Technology School of Aerospace Engineering Huazhong University of Science and Technology School of Mechanical Engineering and Automation Zhejiang Sci-Tech University

Multifidelity surrogates(MFSs) replace computationally intensive models by synergistically combining information from different fidelity data with a significant improvement in modeling efficiency. In this paper, a modified MFS(MMFS) model based on a radial basis function(RBF) is proposed, in which two fidelities of information can be analyzed by adaptively obtaining the scale factor. In the MMFS, an RBF was employed to establish the low-fidelity *** correlation matrix of the high-fidelity samples and corresponding low-fidelity responses were integrated into an expansion matrix to determine the scaling function parameters. The shape parameters of the basis function were optimized by minimizing the leave-one-out cross-validation error of the high-fidelity sample points. The performance of the MMFS was compared with those of other MFS models(MFS-RBF and cooperative RBF) and single-fidelity RBF using four benchmark test functions, by which the impacts of different high-fidelity sample sizes on the prediction accuracy were also analyzed. The sensitivity of the MMFS model to the randomness of the design of experiments(DoE) was investigated by repeating sampling plans with 20 different DoEs. Stress analysis of the steel plate is presented to highlight the prediction ability of the proposed MMFS model. This research proposes a new multifidelity modeling method that can fully use two fidelity sample sets, rapidly calculate model parameters, and exhibit good prediction accuracy and robustness.

关键词： Multi-fidelity surrogate RBF Adaptive scaling factor LOOCV Expansion matrix

Integration of root architecture,root nitrogen metabolism,and photosynthesis of‘Hanfu’apple trees under the cross-talk between glucose and IAA

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Horticultural Plant Journal 2023年第4期9卷 631-644页

作者： Bianbin qi Xin Zhang Zhiquan Mao Sijun qin Deguo lv College of Horticulture Shenyang Agricultural UniversityShenyangLiaoning 110866China College of Horticultural Science and Engineering Shandong Agricultural UniversityTaianShandong 271018China

Sugars and auxin have important effects on almost all phases of plant life cycle,which are so fundamental to plants and regulate similar ***,little is known about the effect of cross-talk between glucose and indole-3-acetic acid(IAA)on growth and development of apple *** examine the potential roles of glucose and IAA in root architecture,root nitrogen(N)metabolism and photosynthetic capacity in‘Hanfu’(Malus domestica),a total of five treatments was established:single application of glucose,IAA,and auxin polar transport inhibitor(2,3,5-triiodobenzoic acid,TIBA),combined application of glucose with TIBA and that of glucose with *** combined application of glucose with IAA improved root topology system and endogenous IAA content by altering the mRNA levels of several genes involved in root growth,auxin transport and ***,the increased N metabolism enzyme activities and levels of genes expression related to N in roots may suggest higher rates of transformation of nitrate(NO3--N)into amino acids application of glucose and ***,single application of TIBA decreased the expression levels of auxin transport gene,hindered root growth and decreased endogenous IAA *** combined with TIBA application effectively attenuated TIBA-induced reductions in root topology structure,photosynthesis and N metabolism activity,and mRNA expression levels involved in auxin biosynthesis and *** together,glucose application probably changes the expression level of auxin synthesis and transport genes,and induce the allocation of endogenous IAA in root,and thus improves root architecture and N metabolism of root in soil with deficit carbon.

关键词： Malus Cross-talk between glucose and IAA Root morphology Nitrogen metabolism Photosynthesis

Hydrogenolysis of organosolv hydrolyzed lignin over high-dispersion Ni/Al-SBA-15 catalysts for phenolic monomers

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Chinese Journal of Chemical Engineering 2021年第4期34卷 307-314页

作者： Ying Xu Pengru Chen Wei lv Chenguang Wang Longlong Ma qi Zhang Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China Key Laboratory of Renewable Energy Chinese Academy of SciencesGuangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China Jiangsu Key Laboratory for Biomass Energy and Material Nanjing 210042China

Efficiency and recycling of catalysts are important for the lignin hydrogenolysis to obtain phenolic *** this work,a series of highdispersion Ni/AlSBA15 catalysts were prepared by a direct and effective preparation method,and then used in the hydrogenolysis of diphenyl ether(DE)and organosolv hydrolyzed lignin(OHL)for phenolic *** universality of asmade catalysts in different solvents and cyclic performance were *** showed that the addition of ethylene glycol(EG)during the loading process of Ni promoted the dispersion of metal *** dispersion of Ni species could highly enhance the conversion of DE and the OHL which Ni/AlSBA15(1EG)exhibited the excellent catalytic *** was found to be most effective solvent on the conversion of DE(99.16%).84.77%liquefaction ratio and 21.36%monomer yield were achieved,and no obvious char was observed after the depolymerization of OHL in ethanol solvent at 280℃for 4 h over the Ni/AlSBA15(1EG)catalyst.

关键词： Lignin Hydrogenolysis depolymerization High-dispersion Ni-based catalyst Al-SBA-15