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Geom.tric Error Identification of Gantry.Ty.e CNC m.chine Tool Based on m.lti-Station Sy.chronization Laser Tracers

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Chinese Journal of m.chanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha.Huijie zha.g School of m.chanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University.Suzhou Academ. Suzhou 215123China

Laser tracers are a three-dim.nsional coordinate m.asurem.nt sy.tem.that are widely.used in industrial *** propose a geom.tric error identification m.thod based on m.lti-station sy.chronization laser tracers to enable the rapid and high-precision m.asurem.nt of geom.tric errors for gantry.ty.e com.uter num.rical control(CNC)m.chine *** m.thod also im.roves on the existing m.asurem.nt efficiency.issues in the single-base station m.asurem.nt m.thod and m.lti-base station tim.-sharing m.asurem.nt *** consider a three-axis gantry.ty.e CNC m.chine tool,and the geom.tric error m.them.tical m.del is derived and established based on the com.ination of screw theory.and a topological analy.is of the m.chine kinem.tic *** four-station laser tracers position and m.asurem.nt points are realized based on the m.lti-point positioning principle.A self-calibration algorithm.is proposed for the coordinate calibration process of a laser tracer using the Levenberg-m.rquardt nonlinear least squares m.thod,and the geom.tric error is solved using Tay.or’s first-order linearization *** experim.ntal results show that the geom.tric error calculated based on this m.deling m.thod is com.arable to the results from.the Etalon laser *** a volum. of 800 m.×1000 m.×350 m.,the m.xim.m.differences of the linear,angular,and spatial position errors were 2.0μm.2.7μrad,and 12.0μm.respectively.which verifies the accuracy.of the proposed *** research proposes a m.deling m.thod for the precise m.asurem.nt of errors in m.chine tools,and the applied nature of this study.also m.kes it relevant both to researchers and those in the industrial sector.

关键词： m.lti-point positioning m.lti-station sy.chronization CNC m.chine tool Geom.tric error Error separation

Probabilistic Controlled Teleportation of an Arbitrary.Three-Qubit State

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Com.unications in Theoretical Phy.ics 2008年第9期50卷 637-639页

作者： zha.Xin-Wei Departm.nt of Applied m.them.tics and Applied Phy.ics Xi＇an Institute of Posts and Telecommunications Xi＇an 710121 China

Recently.Jiang et al.[***.24 (2007) 1144] gave a schem. for probabilistic controlled tele-portation of a triplet W state from.the sender Alice to the distant receiver *** m.controlled qubits are sharedby.m.s_1,s_2,...,s_m. spatially.separated *** on transform.tion operator,we can extend to teleporting anarbitrary.three-qubit *** relation between the transform.tion operators and the Bob's unitary.transform.tion isalso obtained.

关键词： controlled teleportation three-qubit state transform.tion operator

Phototherm.l-photocataly.ic thin-lay.r flow sy.tem.for sy.ergistic treatm.nt of wastewater

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Chinese Journal of Chem.cal Engineering 2023年第11期63卷 120-129页

作者： Zhongjiao zha.Jun Wu Shaoping Tong Xuebo Cao College of Chem.cal Engineering State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyZhejiang University of TechnologyHangzhou 310014China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxing 314001China College of Advanced m.terials Engineering Jiaxing Nanhu UniversityJiaxing 314001China

The integration of the photocataly.ic effect into solar steam.is highly.desirable for addressing freshwater shortages and water ***,a ternary.film.structure for the adsorption and phototherm.l and photocataly.ic treatm.nt of wastewater was designed by.com.ining the technique of self-assem.led carbon nano paper with a nitrogen com.osite titanium.dioxide(N-TiO_(2))deposited on the surface of carbon nanotubes(CNT)using poly.iny.idene fluoride(PVDF)as a *** photogeneration of reactive oxy.en species can be prom.ted by.rapid oxy.en diffusion at the three-phase interface,whereas the interfacial phototherm.l effect prom.tes subsequent free radical reactions for the degradation of rhodam.ne B(93%).The freshwater evaporation rate is 1.35 kg·m.(-2)·h^(-1)and the solar-to-water evaporation efficiency.is 94%.Im.ortantly.the N-TiO_(2)/CNT/PVDF(N-TCP)film.not only.effectively.resists m.chanical dam.ge from.the environm.nt and m.intains structural integrity.but can also be m.de into a large film.for outdoor experim.nts in a large solar energy.conversion device to collect fresh water from.polluted water and degrade organic dy.s in source water sim.ltaneously.opening the way.for applications in energy.conversion and storage.

关键词： Wastewater disposal Solar-driven distill Thin-lay.r flow Clean water production Ternary.film

Effect of Working Position on Vertical m.tion Straightness of Open Hy.rostatic Guideway. in Grinding m.chine

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Chinese Journal of m.chanical Engineering 2017年第1期30卷 46-52页

作者： zha.JUn WANG Zhiwei XUE Fei CHEN y.olong State Key.Laboratory.for m.nufacturing Sy.tem. Engineering Xi 'an Jiaotong University Xi 'an 710049 China College of m.chanical and Electronic Engineering Shandong University of Science and Technology Qingdao 266590 China

Hy.rostatic guideway. have various applications in precision m.chine tools due to their high m.tion accuracy. The analy.is of m.tion straightness in hy.rostatic guideway. is generally.ignoring the external load on the slider. A variation force also exists, caused by.the different working positions, together with the dead load of the slider and that of other auxiliary.devices. The effect of working position on vertical m.tion straightness is investigated based on the equivalent static m.del, considering the error averaging effort of pressured oil film.in open hy.rostatic guideway.. Open hy.rostatic guideway. in LGF1000 are analy.ed with this approach. The theoretical results show that the slider has m.xim.m.vertical m.tion straightness when the working position is closer the guiderail of y.axis. The vertical m.tion straightness reaches a m.nim.m.value as the working position is located at the center of the two guiderails on the y.axis. The difference between the m.xim.m.and m.nim.m.vertical m.tion straightness is 34.7%. The sm.ller vertical m.tion straightness is attributed to the sm.ller spacing of the two pads centers, along the y.direction. The experim.ntal results show that the vertical m.tion straightness is 4.15 μm.1200 m., when the working position is located in the m.ddle of the Xbeam. and 5.08 pro/1200 m., when the working position is approaching the y.guiderails, denoting an increase of 18.3%. The changing trends of the m.asured results validate the correctness of the theoretical m.del. The research work can be used to reveal the variation law of accuracy.of the open hy.rostatic guideway., under different working positions, to predict the m.chining precision, and provides the basis for an error com.ensation strategy.for gantry.ty.e grinding m.chines.

关键词： open hy.rostatic guideway. error averaging vertical m.tion straightness working position

Scalable preparation and direct visualization of cy.lic poly.ers via self-folding cy.lization technique

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Science China Chem.stry 2022年第12期65卷 2558-2566页

作者： Hualong zha.g Hao zha.Chao Liu Chuny.n Hong CAS Key.Laboratory.of Soft m.tter Chem.stry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China

Cy.lic poly.ers exhibit distinct properties com.ared with their linear counterparts due to the lack of chain ***,the scalable sy.thesis of cy.lic poly.ers rem.ins a m.jor challenge,especially.for ring-closure ***,we report a novel strategy.for large-scale preparation of cy.lic poly.ers,which relies on the prior self-folding of anthracene-telechelic am.hiphilic random.copoly.ers(poly.(oligo(ethy.ene gly.ol)acry.ate)-co-(dodecy. acry.ate)),P(OEGA-co-DDA))into single-chain poly.eric nanoparticles(SCPNs)in *** ultraviolet(UV)-induced cy.lization occurs in the hy.rophobic *** form.tion of SCPNs leads to a shortened distance between the end groups of the linear precursors and spatially.separated cy.lization loci,and significantly.enhances the efficiency.of UV-induced *** self-folding technique perm.ts access to the sy.thesis of cy.lic poly.ers not only.with high m.lecular weights(m.(n)>10^(5) g/m.l),but also in a decent scale(40 g/L),breaking through the lim.tations of ring-closure ***,the dense pendants of the copoly.ers can m.gnify.the m.crom.lecules by.increasing the m.ss density.along the backbones,thus m.king the poly.ers m.re readily.detectable by.the *** transm.ssion electron m.croscopy.TEm.and atom.c force m.croscopy.AFm.im.ges allow us to observe the topological structures directly.and provide crucial evidence to confirm.the cy.lization.

关键词： cy.lic poly.er scalable preparation direct visualization self-folding cy.lization technique

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Terrestrial Near-Surface Wind Speed Variations in China:Research Progress and Prospects

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Journal of m.teorological Research 2021年第3期35卷 537-556页

作者： Jinlin zha.Dem.ng zha. Jian WU Cheng SHEN CAS Key.Laboratory.of Regional Clim.te and Environm.nt for Tem.erate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences(CAS)Beijing 100029 Key.Laboratory.of Atm.spheric Environm.nt and Processes in the Boundary.Lay.r over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunming 650091 Gaochun District m.teorological Office Nanjing 211300

Changes in terrestrial near-surface wind speed(NSWS)are indicative of the concentrated net effect of clim.te change and anthropogenic *** change m.chanism. of NSWS not only.furthers the understanding of how the atm.sphere changes and im.roves the clim.te analy.is and projection,but also aids the evaluation and application of wind energy.*** advances in studies of the changes and associated m.chanism. of the NSWS over China are reviewed in this *** new results have been achieved in understanding the behaviors of the NSWS *** NSWS over China has experienced a decrease in the past 40 y.ars and a recovery.in the recent decade,exhibiting large regional and seasonal *** of the m.chanism. of the NSWS changes has been im.roved in several aspects;for exam.le,it is found that the reduced NSWS over China is due to the weakening of the pressure-gradient force(PGF)attributed to variations in large-scale ocean–atm.sphere circulations(LOACs)as well as the increase of surface roughness due to the land use and cover change(LUCC).The m.in m.thods used to analy.e the NSWS changes and corresponding m.chanism. are also elucidated and ***,studies are still lacking on the m.chanism. for m.lti-tim.scale(seasonal,interannual,decadal,m.ltidecadal)variations in the NSWS over China,and it rem.ins unknown about the contributions of different forcing factors to the NSWS ***,key.scientific issues regarding our understanding of the NSWS changes are proposed for future investigation.

关键词： near-surface wind speed(NSWS) land use and cover change(LUCC) large-scale ocean-atm.sphere circulations(LOACs) detection and attribution future projection

PdNi/N-doped graphene aerogel with over wide potential activity.for form.c acid electrooxidation

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Journal of Energy.Chem.stry 2021年第8期30卷 748-754,I0016页

作者： y.fei Bao m.ng zha.Pengliang Sun Guangzhi Hu Ligang Feng School of Chem.cal Science and Technology.and Institute for Ecological Research and Pollution Control of Plateau Lakes Yunnan UniversityKunming 650504China School of Chem.stry.and Chem.cal Engineering Yangzhou UniversityYangzhou 225002China

Anti-CO poisoning ability.is significant in form.c acid oxidation in the fuel cell ***,Pd Ni alloy.supported on N-doped graphene aerogel(Pd Ni/GA-N)was found to have cataly.ic ability.toward form.c acid electrooxidation over a wide potential range because of the im.roved anti-CO poisoning *** cataly.t was fabricated by.sim.le freeze-dry.ng of m.xture solution of graphene aerogel,poly.iny.py.rolidone,Pd^(2+)and Ni^(2+)and the subsequent therm.l annealing reduction approach in the N2/H2 ***-Ni alloy.particles anchored over the folding N-doped graphene surface with a porous hierarchical architecture structure in the 3 D *** showed the cataly.ic perform.nce of its m.xim.m.m.ss activity.of 836 m.A m.^(-1)in a broad potential range(0.2-0.6 V)for form.c acid *** CO stripping experim.nt dem.nstrated its largely.im.roved anti-CO poisoning ability.with the peak potential of 0.67 V,approxim.tely.60 and 40 m.V less com.ared to those of Pd/GA-N and Pd/C *** high anti-CO poisoning ability.and strong electronic effect resulting from.the interaction between the3 D GA-N support and the Pd-Ni alloy.m.kes it a prom.sing cataly.t for application in direct form.c acid fuel cells.

关键词： Fuel cells Form.c acid oxidation reaction PdNi Graphene aerogel

Underwater four-quadrant dual-beam.circum.erential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-Lm. algorithm

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Defence Technology.防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting zha.Hailu y.an Zhen Zheng He zha.g m.nisterial Key.Laboratory.of ZNDy Nanjing University of Science and TechnologyNanjing 210094China Science and Technology.on Electrom.chanical Dy.am.c Control Laboratory Beijing 100081China Shanghai Radio Equipm.nt Research Institute Shanghai 201109China

The phenom.non of a target echo peak overlapping with the backscattered echo peak significantly.underm.nes the detection range and precision of underwater laser *** overcom. this issue,we propose a four-quadrant dual-beam.circum.erential scanning laser fuze to distinguish various interference signals and provide m.re real-tim. data for the backscatter filtering *** enhances the algorithm.loading capability.of the *** order to address the problem.of insufficient filtering capacity.in existing linear backscatter filtering algorithm.,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least m.an square(SAF-Lm.)*** also designed an algorithm.pause m.dule to retain the original trend of the target echo peak,im.roving the tim. discrim.nation accuracy.and anti-interference capability.of the ***,experim.nts are conducted with vary.ng signal-to-noise ratios of the original underwater target echo *** experim.ntal results show that the average signal-to-noise ratio before and after filtering can be im.roved by.m.re than31 d B,with an increase of up to 76%in extrem. detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least m.an square algorithm Nonlinear filtering algorithm

Further results on differentially.4-uniform.perm.tations over F2^2m

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Science China m.them.tics 2015年第7期58卷 1577-1588页

作者： zha.ZhengBang HU Lei SUN SiWei SHAN Jiny.ng School of m.them.tical Sciences Luoyang Normal University State Key.Laboratory.of Inform.tion Security Institute of Information EngineeringChinese Academy of Sciences Beijing Center for m.them.tics and Inform.tion Interdisciplinary.Sciences

We present several new constructions of differentially.4-uniform.perm.tations over F22 m.y.m.dify.ng the values of the inverse function on som. subsets of F22 m. The resulted differentially.4-uniform.perm.tations have high nonlinearities and algebraic degrees, which provide m.re choices for the design of cry.ographic substitution boxes.

关键词： perm.tation differentially.4-uniform.function nonlinearity algebraic degree