This study addresses efficiency limitations in laser hybrid electrochemical machining (LECM) of high aspect-ratio micro holes in TC4 titanium alloy. Through morphological and EDS analysis of hole bottoms, it is identified that machining rate is constrained by: nonuniform electrochemical dissolution in Area III, and poor waste electrolyte renewal causing precipitate and gas accumulation. A synergistic strategy combining the insulation layer retraction and high-temperature electrolyte to enhance the machining efficiency was firstly proposed. Finite element simulations reveal that using high-temperature electrolyte enhances current density and dissolution homogeneity, while tubular electrodes with insulation layer retraction improve discharge flow velocity and electric field distribution. Experimental validation optimized the retraction distance and electrolyte temperature which could improve machining rate and ensure hole accuracy. Ultimately, the holes of 75 mm deep were fabricated at 5.1 mm/min employing above two techniques for the first time, representing an enhancement of 112.5% on machining efficiency. And the maximum processing speed fabricating shallow holes reaches 7 mm/min which is increased by 16.7% compared to conventional LECM. Synergistic use of high temperature electrolytes and insulation layer retraction effectively breaking through the hole machining efficiency ceiling of LECM, furnishing a new method for micro hole fabrication in aero-engine components.

Nickel based single crystal superalloys (NBSCs) are widely used in advanced aero-engines owing to their outstanding high-temperature strength, thermal stability, and corrosion resistance. Laser-electrochemical hybrid machining (LECM) is an emerging technique capable of achieving efficient, damage-free machining of difficultto-machine materials. However, during LECM of NBSCs, the gamma/gamma ' two-phase structure exhibits phase-selective electrochemical dissolution and non-uniform passivation, leading to position-dependent material removal behavior that compromises the machining accuracy and surface integrity. The LECM based on an optical fiber inserted tubular electrode (LECM-OFTE) is employed to achieve stable coupling of laser and electrolytic energy fields, attaining higher laser transmission efficiency and realizing higher machining efficiency. In this study, the laser-induced passivation mechanisms of NBSC DD6 superalloy are systematically investigated under the LECMOFTE process. Morphological and compositional analyses reveal the evolution of passive films and their influence on phase-selective dissolution under different laser intensities. Electrochemical measurements further elucidate the growth, breakdown, and recovery behavior of passive layers under hybrid interactions. Based on the experimental and mechanistic analysis, component-scale LECM of DD6 is further demonstrated using a miniaturized coaxial tubular electrode. Under 12.5 wt% NaNO3 electrolyte and 5 W laser power, 5-mm-deep holes with an aspect ratio of 7 are machined with markedly reduced stray corrosion and tight dimensional repeatability (entrance: 719 +/- 50 mu m, exit: 773 +/- 38 mu m at 50 mu m/s feed rate), corroborating the critical role of laser-enhanced passivation in enabling high-precision machining.

We investigate the long time stability of the solutions to the fractional nonlinear Schrodinger (FNLS) equation under periodic boundary condition i psi(t) + (-Delta)s0 psi partial derivative F (| psi |(2) )/partial derivative psi = 0, x is an element of T , t is an element of R, s(0) is an element of (3/4,1), where (-Delta)(s)(0) denotes the Riesz fractional differentiation defined in [18]. Here F ( z ) is a real-valued polynomial function of z , fulfilling F'(z)|(z) =0 = 0, F"(z)|(z =0) not equal 0. Our findings indicate that for all s 0 E (3/4, 1) and almost all R-small initial data in Sobolev norm, the corresponding solutions remain their small magnitude over time-intervals of length R-|lnR|gamma with 0 < R << 1, 0 < gamma < 1/5. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Laser electrochemical machining is an innovative composite processing method, achieving high surface quality and efficient shaping for difficult-to-machine materials through the combined effects of laser and electrochemical energy. Electrochemical machining adjusts the parameters of the physical field to eliminate the recast layer generated by laser ablation. In addition, the increase in electrolyte temperature caused by the laser can promote electrochemical dissolution. This work proposed a new multiphysics simulation model to explore the structure formation mechanism based on the temporal variations of temperature, electric, and flow fields during composite processing. The laser-coupled electrochemical machining used a three-current model. The temperature field variation considered not only the laser irradiation factor but also the effect of convective heat transfer induced by fluid flow. Moreover, temperature variation influences electric and flow fields, changing the physical parameters of electrolytes, such as conductivity and dynamic viscosity. Transient deformation geometry was used to uncover the material removal process during composite machining and then predict the final profile of the obtained structures. The manufacturing process could be elaborately described by the multiple physical fields using the established simulation model. Finally, an experimental study was conducted to validate the reasonability of the proposed simulation model. The role of laser effects in composite machining was also highlighted through the comparison of theoretical and experimental results.

The laser-electrochemical hybrid machining (LECM) based on a tube electrode has the potential for fabricating high aspect-ratio structures. To solve the problem of laser energy attenuation caused by electrolyte interference during laser transmission, a laser-electrochemical hybrid machining process based on a novel dual-cathode and dual-channel tube electrode inserted with an optical fiber (OF-DDTE) is proposed. To achieve efficient transmission and reliable interaction of laser energy field and electrolyte flow field, the structures of tube electrode and spindle head are designed and optimized. Multiphysics simulations are performed to optimize the spatial distribution of hybrid energy in LECM, focusing on the configuration of cathodes and flow channels, the retraction distance of insulation layer, and the electrolyte chamber structure of the spindle head. Using a self-developed experimental system, electrolyte-assisted laser ablation experiments and laser-electrochemical hybrid machining experiments are carried out on superalloys to verify the OF-DDTE capabilities and hybrid machining characteristics, including the laser transmission efficiency, the spatial distribution features of hybrid energy fields, and the machining potential for high aspect-ratio holes. The results show that the novel electrode can achieve the laser transmission efficiency up to 92.4 %, accelerate material dissolution, and enhance flow-field renewal. Using the designed tube electrode with an outer diameter of Phi 1.24 mm, recast-free small holes are machined with an average diameter of Phi 1.36 mm, an average roundness error of 5.6 mu m, an average wall roughness Ra4.78 mu m, a repeat dimensional accuracy <+/- 3 mu m, and a repeat shape accuracy <+/- 0.45 mu m. Deep holes with an aspect-ratio of 11 and a taper angle of 0.008 degrees are successfully machined.

Objective Laser and electrochemical hybrid machining is a composite processing method that combines laser and electrochemical processing. It can be used to process hard conductive materials. It can accelerate the electrochemical dissolution rate, avoiding recasting layers, thus improving the surface quality. This study proposes a tubular electrode-coupled laser and electrochemical hybrid machining technology that uses a newly designed tubular electrode. This realizes coaxial transmission of laser and electrochemical energy inside the tubular electrode and controllable coupling at the processing gap, which is suitable for high-quality small hole processing with a high aspect ratio. A coupling mechanism dominated by laser and an electrochemical processing is proposed based on the controllable adjustment of the laser and electrochemical energy at the processing gap. The effects of the temperature rise in the laser irradiation zone on the electrolyte conductivity, current density, liquid-phase mass transfer, and electrochemical dissolution rate, as well as the effects of bubbles and impurities generated during electrolysis on the laser energy. Material removal models for laser and electrochemical hybrid machining are established, and preliminary simulation analysis and experimental research on laser and electrochemical hybrid machining are conducted. Methods This study introduced a tool for laser and electrochemical hybrid machining with a tubular electrode that confined the electrolyte and laser beam coaxially or asynchronously. In addition, it utilized a coaxial optical fiber inside the tubular electrode to enable total internal reflection of the laser, thereby achieving independent control of laser and electrochemical energy within the tubular electrode. Based on this process, a coupling mechanism for the laser and electrochemical energy was explored, as well as the mechanisms where the laser and electrolysis dominate in the hybrid machining process. By investigating the temporal and spatial distributions of local temperature and stress induced by coupled energy, we study the influence of laser on mass transport and electrode potential in the micro-region of electrochemical machining. A theoretical model for the kinetic behavior of materials removal under the action of hybrid energy was established, and a preliminary simulation analysis of laser and electrochemical hybrid machining was conducted. The results of this study laid a theoretical foundation for the fabrication of complex structures with high quality and aspect ratio. Results and Discussions First, the influence of laser power density on the machining capability of workpiece materials is explored (Fig.2). When the laser power density is low, the laser affects the thermal and electrochemical parameters of the workpiece material and the changes in the electrolyte's electrical conductivity, electrolytic current density, ion diffusion rate, bubble rate, and electrode potential within the machining gap through thermal effects. When the laser power density reaches the electrolyte breakdown threshold, the laser impacts the laser and electrochemical hybrid machining process through both thermal and mechanical effects. Second, based on the controllable adjustment of the laser and electrochemical energy within the tubular electrode, the state changes in the coupling region caused by these energy are classified into three mechanisms: laser-assisted electrochemical machining, laser and electrochemical hybrid machining, and electrolysis-assisted laser machining (Fig.4). Furthermore, through theoretical analysis and preliminary simulation studies, the electric field and current density distributions in the laser and electrochemical hybrid energy field, the flow field distribution, the temperature distribution, and the resulting machining surface are investigated. This facilitates in the evaluation of material removal at different locations on the workpiece during the laser and electrochemical hybrid machining processes. Finally, three-dimensional morphologies of blind holes produced by the only electrochemical machining and laser and electrochemical hybrid machining are compared. The advantages of the hybrid laser and electrochemical processing are confirmed (Fig.9). It successfully manufactures through-holes with a diameter of 1.26 mm and a high aspect ratio of 16:1 and through-holes with a diameter of 1.25 mm and high aspect ratios of 42:1 (Figs.10 and 11). Conclusions Laser and electrochemical hybrid machining typically suffer from defects such as stray corrosion caused by electrochemical machining and resolidification defects caused by laser machining. To avoid the occurrence of defects and improve the surface quality, this study introduces a tool for laser and electrochemical hybrid machining with a tubular electrode. This enables the coaxial transmission of laser and electrochemical energy within the tubular electrode and the controlled coupling at the machining gap, thereby effectively preventing defects such as stray corrosion and resolidification of layers. This approach is suitable for fabricating complex structures with high quality and aspect ratios. Based on the controllable adjustment of the laser and electrochemical energy, this study proposes mechanisms in which laser and electrolysis dominate, and both cooperate in hybrid machining. The thermal effects of the laser on the laser and electrochemical hybrid machining and the influence of the pulse width of electrolysis on the process are analyzed. This study establishes a theoretical model for the kinetic behavior of material removal under the action of hybrid energy. Preliminary investigations are also conducted on the time and spatial distribution of the hybrid energy field and its impact on the machining surface using simulation models. Through experiments, the advantages of laser and electrochemical hybrid machining are verified. Small holes with a diameter of 1.25 mm and aspect ratio of up to 42:1 without resolidified layers are successfully produced. This study lays a theoretical foundation for the fabrication of complex structures with high quality and aspect ratio.

In this article, we study a class of reflecting stochastic differential equations whose coefficients depend on image measures of solutions under a given initial measure in Wasserstein space P-2. By the penalization method, the image process, which is a diffusion process in P-2, is constrained in a priori given domain O ? P-2. The large deviation principle for this reflecting image process is also established by weak convergence method.

This study designed an optoelectronic chip, integrating a photodiode array, transimpedance amplifier, fully differential amplifier, and bias circuit, to meet the application requirements of reflective photoelectric encoders. First, the photodiode array was designed according to the imaging principle of the reflective encoder. The adjustable gain transimpedance amplifier and the fully differential driver amplifier were then cascaded. Regarding the signal processing circuit, it could increase load capacity in addition to reducing the noise of the readout signal. Subsequently, the design integrated the bias circuit to provide a wide power supply voltage input range and effective power supply ripple rejection. The whole chip was fabricated based on a 0. 35-um photoelectric CMOS process. By building a test environment, the photoelectric chip can work normally in the wide power supply voltage range of 3. 5-6 V, and the incremental signal output within 6000 r/min has good orthogonality. The results of angle measurement showed that the maximum error of angle measurement is 4. 752″ and 5. 04″ under forward and reverse rotations, respectively.Using a 5 V supply voltage, the DC power consumption of the circuit is 66. 5 mW. The overall chip area is 5. 91 mm×2. 81 mm. In general, the proposed optoelectronic chip can meet the requirements of high integration of photoelectric chips, good signal orthogonality, wide power supply voltage input range, and high power supply ripple suppression ability. Therefore, it is suitable for reflective photoelectric encoders.

NAND Flash存储器具有读写速度高、容量大、可靠性高等优点,被广泛用于固态硬盘、存储卡、U盘等应用中,成为数据中心和消费电子的核心存储元件.开放NAND闪存接口国际标准作为NAND Flash与控制器之间通用接口协议,严格定义了数据传输相关的控制指令、工作时序、电平要求等规范.根据当前ONFI 4.2国际协议标准对NAND Flash高速接口的多相位读写时钟的性能要求,设计了一种具有带宽自适应式延迟链结构的四相输出延迟锁相环,具有宽频锁定和高精度锁定的优点.在设计延迟锁相环中,为了解决宽频率范围下传统延迟链延迟时间有限的问题,提出一种可配置延迟链电路结构,可在不同频段下选择使用相应的延迟单元,从而扩展频率范围并保持精度;提出一款基于鉴频器的自适应控制电路,能跟踪输入时钟频率,自动配置延迟链,实现输出延迟锁相环带宽的自适应.基于SMIC 28nm HKCMOS工艺完成了输出延迟锁相环电路设计.仿真验证结果表明,在25℃、0.9 V电源电压、tt工艺角下,该输出延迟锁相环可产生四相时钟生成,且锁定范围为[22 MHz,1.6 GHz],最高锁定精度为17ps,完全满足ONFI国际标准对多相时钟产生的频率范围和精度要求.

A photodiode area-compensation method based on light intensity distribution characteristics is introduced to solve the problem of the hybrid optical encoder’s inconsistent absolute code output signals. This method performs area compensation of different degrees according to the irradiance received by the photodiodes at different positions, thus achieving the consistency of output signals and reducing the bit error rate of absolute code signals. Based on the 0.35 μmm CMOS process, a four-channel photodiode array chip for a reflective hybrid optical encoder was designed. Moreover, the absolute code photodiode arrays were designed with area compensation. The test results show that the square wave duty cycle error of the output signals is less than 2% when the LED light source works normally. When the LED working current changes by ±2.85 mA, the output signal’s square wave duty cycle error is less than 3.1%. In each case, the square wave duty cycle error of the output signals is small, so it can be seen that the area compensation method based on light intensity distribution can achieve good consistency of the output signal. The chip has been taped and packaged, and the chip area is 21.45 mm2.

Constraint-based genome-scale metabolic network models (genome-scale metabolic models, GEMs) have been widely used to predict metabolic phenotypes. In addition to stoichiometric constraints, other constraints such as enzyme availability and thermodynamic feasibility may also limit the cellular phenotype solution space. Recently, extended GEM models considering either enzymatic or thermodynamic constraints have been developed to improve model prediction accuracy. This review summarizes the recent progresses on metabolic models with multiple constraints (MCGEMs). We presented the construction methods and various applications of MCGEMs including the simulation of gene knockout, prediction of biologically feasible pathways and identification of bottleneck steps. By integrating multiple constraints in a consistent modeling framework, MCGEMs can predict the metabolic bottlenecks and key controlling and modification targets for pathway optimization more precisely, and thus may provide more reliable design results to guide metabolic engineering of industrially important microorganisms.

By a probabilistic method, we prove the existence and uniqueness of weak solutions to Neumann problems for a class of semi-linear elliptic partial differential equations with nonlinear singular divergence terms, which can only be understood in distributional sense. This leads to the further study on a new class of infinite horizon backward stochastic differential equations, which involves integrals with respect to a forward–backward martingale and a singular continuous increasing process.

Objective A microgripper is an essential part of the micromanipulationsystemAstheendeffectorofthemicrooperatingsystemthejawendfaceofthemicrogripperispronetowearadsorptionofimpuritiesiceorfrostduringoperationMosttraditionalmicrogrippersareintegrallymachinedandtheoverallreplacementwillresultinwastedresourcesThisstudyreportsadetachablemicrogripperwithsuperhydrophobicpropertiesFirstaroughmicrostructurewasmachinedontheendfaceofthejawswheretheoperationisperformedusingananosecondlaserwithacentralwavelengthof1064nmThentheyaremodifiedbyimmersingtheminanontoxicstearicacidsolutionThusabionicsuperhydrophobicsurfaceisobtainedThissurfacehasexcellentcorrosionresistanceself-cleaningantiicingandantibacterialpropertiesX-rayphotoelectronspectroscopyXPStechniqueisemployedtoanalyzethechemicalcompositionofthepristinealuminumAl-IandsuperhydrophobicaluminumAl-IIsurfacesthecorrosionresistanceofbothsurfacesinacidsaltandalkalienvironmentsistestedusingelectrochemicalexperimentsFurthertheantifoulingantifreezingandantibacterialpropertiesofbothsurfacesaretestedusingself-cleaningantiicingandantibacterialexperimentsWeexpectthatourbasicstrategiesandfindingswillenhancetheperformanceandextendtheservicelifeofthemicrogrippersMethodsBecausethemicrogripperismadeof7075spacealuminumusedtofacilitatelaterobservationtestingandanalysisa7075aluminumsamplewithsizeandthicknessof10mmx10mmand1mmrespectivelyisusedforthetestinsteadoftheendfaceofthejawsFirstananosecondlaserisusedtoetchagrid-likemicrostructureonthesurfaceofthesampleandthenitisimmersedinanontoxicstearicacidsolutionwithaconcentrationof005molLfor30mintoreducethesurfacefreeenergyFurtheritisremovedandplacedinadryingovenat60 degrees Cfor1hThesamplesurfacewillacquiretheexpectedsuperhydrophobicpropertiesusingthisprocedureAccordingtothefunctionalrequirementsofthemicrogripperthepreparedsuperhydrophobicsamplesurfacesareanalyzedforsurfacecompositionandtestedforcorrosionresistanceself-cleaningantiicingandantibacterialpropertiesThechemicalcompositionofAl-IandAl-IIsurfacesisdetectedusingtheXPStechniqueFurtherthemorphologyofthesamplesurfacesbeforeandaftercorrosionbyacidsaltandalkaliischaracterizedusingscanningelectronmicroscopyTheantiicingandself-cleaningperformanceofthesamplesurfacesareevaluatedusinganenvironmentaltestchamberandself-designedself-cleaningexperimentsThebacterialdistributionandsurvivalstatusofthesamplesurfacesarecharacterizedusinglaserconfocalmicroscopyandtheantibacterialperformanceischaracterizedusingplatecoatingexperimentstocalculatethebacterialinhibitionrateResultsandDiscussionsThelattice-likemicrostructuresobtainedfromthesamplesurfacepreparationhavehighsuperhydrophobicitywithaveragecontactandrollinganglesof1567 degrees and1088 degrees respectivelyTheXPStestresultsshowthatthesurfaceofbothsamplesmainlycontainsCOandAlelementsAfterlaserirradiationthegeneratedAl2O3onthesurfacecausedtheOatomicnumberfractiontoincreaseby2451%TheC1shigh-resolutionspectraofthesuperhydrophobicsamplesexhibitasignificantincreaseinCatomicnumberfractionfollowingthestearicacidmodificationtreatmentindicatingthatstearicacidreactedwiththesurfaceAltoformlowsurfaceenergyaluminumstearateduringthechemicalmodificationprocessTheC-CHcontentisashighas8281%occupyingthestrongestpeakwhichindicatesthatthelong-chainmoleculesofstearicacidhavesuccessfullyadheredtothesurfaceoftheAl-IIsampleintheformofaluminumstearateFig5ElectrochemicalexperimentsandSEMresultsshowthatthecorrosionresistanceofthesuperhydrophobicsurfaceinasaltsolutionisbetterthanitsresistancetoacidsandbasesthetotalimpedancemodulusofsuperhydrophobicAl-IIsampleisbetterthanthatofpristineAl-IsampleThisimpliesthatthesuperhydrophobicsurfacewitharoughmicrostructurecansignifican tlyenhancethecorrosion inhibitionofaluminummaterialsFigs6--8Table1Theself-cleaningtestresultsshowthatthedropletscaneffectivelyremovetheimpuritiesfromthesurfaceoftheAl-IIsampleindicatingthatthesuperhydrophobicsurfacehasagoodself-cleaningabilityFig10Theresultsofthetwenty-minuteantiicingexperimentsshowthattheAl-IIsamplehasexcellentsuperhydrophobicitywithlowadhesionabilityandnosignificanticingoccurredduringthetestwhereastheadheringicelayeronthesurfaceoftheAl-Isamplehasamassof1283gandshowspoorantiicingperformanceinthecryogenicenvironmentFig11TheresultsoflaserconfocalmicroscopecharacterizationintheantibacterialexperimentshowthatthenumberofstrainsadheringtothesurfaceoftheAl-IIsampleissignificantlylowerthanthatoftheAl-IsampleindicatingthatthepreparedsuperhydrophobicsamplehasastrongresistancetobacterialadhesionFig12Furthertheresultsoftheplate-coatingexperimentshowthattheantibacterialrateoftheAl-IIsampleis38timeshigherthanthatoftheoriginalAl-Isamplewhichprovesthatthealuminum-basedsuperhydrophobicsurfacewithlattice-likemicrostructurehascertainbactericidalpropertiesTable2ConclusionsInthisstudywedesignandconstructadetachablemicrogripperwithabionicsuperhydrophobicstructureinthejawendofthegripperbodywhichaddressesseveralproblemsofthetraditionalmicrogripperThemainresearchcontentsandinnovationsareasfollows1themicrogripper????sbasebodyandtheleftandrightclampingbodiesaredesignedseparatelyandconnectedbyboltsThisdesignincreasestheflexibilityofthemicrogripperwhichcanreplacethecorrespondingbodybasedondifferentclampingobjectsandworkingconditionsWhenthejawendfaceisdamagedbyrepeateduseitisunnecessarytoreplacethewholemicrogripperhoweveronlythebodypartcanbereplaced2Thelaser-texturedjawendfacesaresoakedinalowsurfaceenergystearicacidsolutiontoobtainsuperhydrophobicpropertiesThesurfaceobtainedthroughthismethodhasaroughmicrostructureandlowsurfaceenergythusforminganairlayerbetweenthematerialandtheliquiditeffectivelypreventsthecontactofthematerialsurfacewithcorrosivesolutionscommonwaterdropletsandbacterialsolutionsinhibitingtheadhesionofdropletsThisenablesthejawendfacestoacquireself-cleaninganticorrosionantiicingandantifrostpropertiesthus effectivelyenhancing the clamping performance of the microgripper

In this paper, we give a probabilistic interpretation for solutions to the Neumann boundary problems for a class of semi-linear parabolic partial differential equations (PDEs for short) with singular non-linear divergence terms. This probabilistic approach leads to the study on a new class of backward stochastic differential equations (BSDEs for short). A connection between this class of BSDEs and semi-linear PDEs is established.

研究了聚丙烯酸类高吸水树脂(SAR)粒子尺寸对性能的影响,对干燥样品采用标准筛进行了筛分处理,得到粒子尺寸依次减小的样品.在流变剪切模式下测定了样品黏度,通过倒置实验法测定了临界凝胶浓度,饱和吸水能力在室温环境下得到,保水性能通过将饱和凝胶静置在恒定环境温度,计算相等时间间隔内凝胶质量差得到.结果发现当粒子尺寸分布范围较小时,SAR的性能是依赖于粒径的,随着粒子尺寸的减小,SAR吸水倍率下降,附着厚度减小,凝胶的保水性能下降,饱浓度增大;流变测试发现吸水树脂粒径尺寸的大小对饱和状态下黏度的影响不大.通过研究SAR粒径尺寸对其吸水及保水性能和流变性能的影响,为吸水树脂的实际应用提供了参考.

In this paper, we establish an existence and uniqueness result for the system of quasilinear stochastic partial differential equations (SPDEs for short) with reflection in a convex domain in RK by analytical approach. The method is based on the approximation of the penalized systems of SPDEs.

A Freidlin-Wentzell type large deviation principle is established for stochastic partial differential equations with slow and fast time-scales, where the slow component is a one-dimensional stochastic Burgers equation with small noise and the fast component is a stochastic reaction-diffusion equation. Our approach is via the weak convergence criterion developed in [3].

通过不同的发泡工艺和成型工艺制备了密度相近的热塑性聚氨酯发泡片材(TPU-FS)和发泡珠粒成形体(ETPU)材料,研究了2种泡沫材料的形貌与力学性能的关系.通过扫描电镜表征了2种聚氨酯泡沫的结构;利用万能试验机研究了二者的单向压缩性能和循环压缩性能;用旋转流变仪表征了材料在不同压力下的流变性能.研究发现,相近密度下,T PU-FS和ET PU泡沫具有相近的泡孔面积占有率,但是ET PU发泡区域泡孔的平均孔径远大于T PU-FS泡沫;在循环压缩试验中,T PU-FS泡沫具有较高的损耗能和损耗百分比;流变实验中,在不同压力时,ET PU泡沫的储能模量和损耗模量均低于T PU-FS泡沫,且阻尼因子(tanδ)较小,T PU-FS泡沫的tanδ有一定的频率依赖性,而ET PU泡沫的tanδ随频率的变化不明显.同时,对密度相近的T PU-FS泡沫和ET PU泡沫的形貌与损耗百分比的关系进行了初步探讨.

In the present paper, without Rüssmann's nondegenderate condition we show the persistence of KAM invariant tori. Using this theorem we obtain the persistence of invariant tori for degenerate systems rising from restricted three-body problems, especially, for Lagrange equilibrium position L2 with certain degeneracy.

We prove the existence and uniqueness of solutions to a kind of quasilinear stochastic integral-partial differential equations with obstacles. Our method is based on the probabilistic interpretation of the solutions so that penalization method can be applied to a sequence of backward doubly stochastic differential equations with jumps. Relations between regular potentials and regular measures play an important role.