汉字构形演变的历史文化动因及内在机制

汉字从其产生起就一直处于不断发展演进之中,作为汉字形体符号的生成方式,汉字构形方式也随汉字体系发展而演进,经历了形化、意化、音义化三个阶段的动态演变过程。社会生产活动、主体认知能力和汉民族文化传统等是影响汉字构形演变的历史文化动因。汉字构形演变有其内在机制,包括取象构形的形化与仿拟机制、得意忘象的意化与优化机制、形音结合的音义化与衍生机制等。

战国楚简“耕”字的构形演变及隶定标准探讨

战国简帛著录书和工具书中,常用"耒""力""■"等作为楚简"耕"字中"争"形构件的隶定字。通过考察这些构形的演变序列,可以发现"耒"和"力"两个构件不存在通用的情况,构形中的"力"与"争"因"爪"形的增减成为同形构件。楚简"耕"字的右旁应隶作"争",省"爪"的"争"形可隶作"力";以"力"为偏旁的字形中,虽有部分累增"爪"符之"力"与"争"同形,因其赘加的"爪"是羡符,则不应隶作"■"或"争",当依旧隶作"力"。通过对楚简"耕"字隶定标准的研究,可见新时期出土文献整理工作应当进一步完善规范统一的隶定标准。

新世纪以来的汉字构形研究

新世纪以来,文字学研究取得了令人瞩目的成绩,汉字构形研究也不例外。这一时期,文字学研究逐渐加强对汉字本体的研究,探讨汉字的形体依一定的理据构成和演变的规律。关于汉字构形的研究成果大量涌现:一是关于汉字构形分析的研究,二是关于汉字构形系统的研究,三是关于汉字构形演变的研究。这些研究标志着汉字构形理论已经相对成熟,汉字构形研究进入了一个崭新的阶段。

Effects of deformation parameters on microstructure and texture of Mg−Zn−Ce alloy

Compression tests were performed on the Mg−6Zn−0.5Ce(wt.%)alloy using a Gleeble−1500 thermomechanical simulator testing system at temperatures of 250,300,350℃ and strain rates of 0.001,0.01,0.1 s^−1.The microstructure and texture evolution of the Mg−6Zn−0.5Ce alloy during hot compression were investigated by optical microscopy(OM)and electron backscattered diffraction(EBSD).The results showed that Zener−Hollomon parameters obtained from the deformation processes had a significant effect on the dynamic recrystallization and texture of the Mg−6Zn−0.5Ce alloy.The fraction of undynamically recrystallized(unDRXed)regions increased,and the dynamically recrystallized(DRXed)grain size decreased with increasing the Zener−Hollomon parameters.The texture intensity of the DRXed regions was weaker compared with that in the unDRXed regions,which resulted in a sharper texture intensity in the samples deformed with higher Zener−Hollomon parameters.The increase in recrystallized texture intensity was related to preferred grain growth.

Enhanced mechanical properties and formability of hot-rolled Mg-Zn-Mn alloy by Ca and Sm alloying

In order to broaden the application of wrought Mg alloy sheets in the automotive industry,the influence of Ca and Sm alloying on the texture evolution,mechanical properties,and formability of a hot-rolled Mg-2Zn-0.2Mn alloy was investigated by OM,XRD,SEM,EBSD,tensile tests,and Erichsen test.The results showed that the average grain size and basal texture intensity of Mg-2Zn-0.2Mn alloys were remarkably decreased after Ca and Sm additions.0.64 wt.%Ca or 0.48 wt.%Sm addition significantly increased the tensile strength,ductility and formability.Moreover,the synergetic addition of Sm and Ca improved the ductility and formability of Mg-2Zn-0.2Mn alloy,which was due to the change of Ca distribution and further reduction of the size of Ca-containing particles by Sm addition.The results provided a possibility of replacing RE elements with Ca and Sm in Mg alloys which bring about outstanding mechanical properties and formability.

论战国简平直化的差异——以楚简《说命》和秦简《为吏之道》比较为中心

在战国文字简化、草化的演变趋势下,平直化及方折化成为文字演变初期的基础变革手段,对秦“书同文”的推行形成便利的条件,也间接成为隶变发生的绪因。本文通过对《说命》和《为吏之道》的比较分析,研究其中平直化异同因素和平直化程度的差异,从而进一步探究战国楚简平直化的特点及对后世书法影响。

Shape controlling and property optimization of TA32 titanium alloy thin-walled part prepared by hot forming

The hot flow behaviors,microstructure evolution and fractographs were studied to optimize the hot forming process of the TA32 titanium alloy thin-walled part.A set of microstructure-based constitutive equations were developed based on the experimental data,which described the relationships among the hot flow stresses and the evolution of phase volume fraction,dislocation density,grain size and damage.The constitutive model was imported into ABAQUS 6.14 to simulate the hot forming process for a typical thin-walled part.The effective strain,dislocation density and damage distribution as well as forming defects of formed parts under different process parameters were predicted.A qualified part without wrinkling and fracture defects was produced at a loading speed of 5 mm/s at 800℃ by the modified blank shape,where the maximum damage value was only 18.3%.The accuracy of constitutive model and finite element(FE)simulation was verified by the microhardness tests,which indicates that the FE model based on physical internal-state variables can well optimize the hot forming process of TA32 titanium alloy complex parts.

Hot compressive deformation behavior and microstructure evolution of HIPed FGH96 superalloy

Hot deformation behavior and microstructure evolution of hot isostatically pressed FGH96 P/M superalloy were studied using isothermal compression tests. The tests were performed on a Gleeble-1500 simulator in a temperature range of 1000-1150 °C and strain rate of 0.001-1.0 s-1, respectively. By regression analysis of the stress—strain data, the constitutive equation for FGH96 superalloy was developed in the form of hyperbolic sine function with hot activation energy of 693.21 kJ/mol. By investigating the deformation microstructure, it is found that partial and full dynamical recrystallization occurs in specimens deformed below and above 1100 °C, respectively, and dynamical recrystallization （DRX） happens more readily with decreasing strain rate and increasing deformation temperature. Finally, equations representing the kinetics of DRX and grain size evolution were established.

Microstructure evolution of 7050 aluminum alloy during hot deformation

Hot compression of 7050 aluminum alloy was performed on Gleeble 1500D thermo-mechanical simulator at 350 ℃ and 450 ℃ with a constant strain rate of 0.1 s-1 to different nominal strains of 0.1, 0.3 and 0.7. Microstructures of 7050 alloy under various compression conditions were observed by TEM to investigate the microstructure evolution process of the alloy deformed at various temperatures. The microstructure evolves from dislocation tangles to cell structure and subgrain structure when being deformed at 350 ℃, of which dynamic recovery is the softening mechanism. However, continuous dynamic recrystallization (DRX) occurs during hot deformation at 450 ℃, in which the main nucleation mechanisms of DRX are subgrain growth and subgrain coalescence rather than particle-simulated nucleation (PSN).

Hot deformation behaviors and dynamic recrystallization mechanism of Ti-35421 alloy inβsingle field

Hot deformation behaviors and microstructure evolution of Ti-3Al-5Mo-4Cr-2Zr-1Fe(Ti-35421)alloy in theβsingle field are investigated by isothermal compression tests on a Gleeble-3500 simulator at temperatures of 820-900°C and strain rates of 0.001-1 s^(-1).The research results show that discontinuous yield phenomenon and rheological softening are affected by the strain rates and deformation temperatures.The critical conditions for dynamic recrystallization and kinetic model of Ti-35421 alloy are determined,and the Arrhenius constitutive model is constructed.The rheological behaviors of Ti-35421 alloys aboveβphase transformation temperature are predicted by the constitutive model accurately.The EBSD analysis proves that the deformation softening is controlled by dynamic recovery and dynamic recrystallization.In addition,continuous dynamic recrystallization is determined during hot deformation,and the calculation model for recrystallization grain sizes is established.Good linear dependency between the experimental and simulated values of recrystallized grain sizes indicates that the present model can be used for the prediction of recrystallized grain size with high accuracy.

Characteristics of hot tensile deformation and microstructure evolution of twin-roll cast AZ31B magnesium alloys

High temperature tensile properties and microstructure evolutions of twin-roll-cast AZ31B magnesium alloy were investigated over a strain rate range from 10-3 to 1 s-1.It is suggested that the dominant deformation mechanism in the lower strain rate regimes is dislocation creep controlled by grain boundary diffusion at lower temperature and by lattice diffusion at higher temperatures,respectively.Furthermore,dislocation glide and twinning are dominant deformation mechanisms at higher strain-rate.The processing map,the effective diffusion coefficient and activation energy map of the alloy were established.The relations of microstructure evolutions to the transition temperature of dominant diffusion process,the activation energy platform and the occurrence of the full dynamic recrystallization with the maximum peak efficiency were analyzed.It is revealed that the optimum conditions for thermo-mechanical processing of the alloy are at a temperature range from 553 to 593 K,and a strain rate range from 7×10-3 to 2×10-3 s-1.

Wavefield reconstruction inversion with weaktotal-variation constraint based on first arrival traveltime tomography

The objective function of full waveform inversion is a strong nonlinear function,the inversion process is not unique,and it is easy to fall into local minimum.Firstly,in the process of wavefield reconstruction,the wave equation is introduced into the construction of objective function as a penalty term to broaden the search space of solution and reduce the risk of falling into local minimum.In addition,there is no need to calculate the adjoint wavefield in the inversion process,which can significantly improve the calculation efficiency;Secondly,considering that the total variation constraint can effectively reconstruct the discontinuous interface in the velocity model,this paper introduces the weak total variation constraint to avoid the excessive smooth estimation of the model under the strong total variation constraint.The disadvantage of this strategy is that it is highly dependent on the initial model.In view of this,this paper takes the long wavelength initial model obtained by first arrival traveltime tomography as a prior model constraint,and proposes a weak total variation constrained wavefield reconstruction inversion method based on first arrival traveltime tomography.Numerical experimental results show that the new method reduces the dependence on the initial model,the interface description is more accurate,the error is reduced,and the iterative convergence efficiency is significantly improved.

Research on damage evolution of metal plate based on improved micropolar peridynamic model

To study the damage evolution of the metal plate in elastic and plastic deformation stages, an improved micropolar peridynamic model is proposed to simulate the deformation process and damage evolution of metal materials with variable Poisson’s ratios in the elastic-plastic stages. Firstly, both the stretching and bending moments of the bonds between the material points are added to peridynamic pairwise force functions, and the coordinate transformation of the micro-beam made up of bonds is deduced. Therefore, the numerical calculation implementation of the improved micropolar peridynamic model is obtained. Then, the strain values are obtained by solving the difference equation based on the displacement values of material points, and the stress values can be calculated according to generalized Hook’s law. The elastic and plastic deformation stages can be estimated based on the von Mises yield criterion, and different constitutive equations are adopted to simulate the damage evolution. Finally, the proposed micropolar peridynamic model is applied to simulate the damage evolution of a metal plate with a hole under velocity boundary conditions, and the effectiveness of the model is verified through experiments. In the experiments, the displacement and strain distributions in the stretching process are analyzed by the digital image correlation(DIC) method. By comparing the results, the proposed model is more accurate than the bond-based peridynamic model and the error of the proposed model is 7.2% lower than that of the bond-based peridynamic model. By loading different velocity boundary conditions, the relationship between the loads and damage evolution is studied.

Spectra response from macromolecular structure evolution of tectonically deformed coal of different deformation mechanisms

Coals with different deformation mechanisms(brittle deformation,brittle-ductile deformation,and ductile deformation) repre-sent different ways in macromolecular structure evolution based on the metamorphism.The evolution of coal structure could affect the occurrence condition of coalbed methane(CBM) because the nanopore structure affected by macromolecular struc-ture is the most important reservoir for CBM.This paper analyzes the evolutions and mechanisms of structure and functional group of tectonically deformed coals(TDCs) collected from Huainan-Huaibei coalfield using X-ray diffraction(XRD),Raman spectroscopy,and Fourier Transform Infrared(FTIR) spectroscopy methods.The results show that the macromolecular struc-ture evolutions of TDC are different from the primary structure coal as a result of the different metamorphic grade and defor-mation mechanisms.The different deformation mechanisms variously affect the process of functional group and polyconden-sation of macromolecular structure.Furthermore,the tectonic deformation leads to secondary structural defects and reduces the structure stability of TDC.The coupled evolution on stacking and extension caused by the changes of secondary structural de-fects results from different deformation mechanisms.We consider that the changes of chemical structure and secondary struc-tural defects are the primary reasons for the various structure evolutions of TDC compared with primary structure coal.

The evolution of copulation frequency and the mechanisms of reproduction in male Anolis lizards

The evolution of many morphological structures is associated with the behavioral context of their use, particularly for structures involved in copulation. Yet, few studies have considered evolutionary relationships among the integrated suite of structures associated with male reproduction. In this study, we examined nine species of lizards in the genus Anolis to determine whether larger copulatory morphologies and higher potential for copulatory muscle performance evolved in association with higher copulation rates. In 10--12 adult males of each species, we measured the size of the hemipenes and related muscles, the seminiferous tubules in the testes, and the renal sex segments in the kidneys, and we assessed the fiber type composition of the muscles associated with copulation. In a series of pbylogenetically-informed analyses, we used field behavioral data to determine whether observed rates of copulation were associated with these morphologies.We found that species with larger hemipenes had larger fibers in the RPM （the retractor penis magnus, a muscle that controls hemipenis movement）, and that the evolution of larg- er hemipenes and RPM fibers is associated with the evolution of higher rates of copulatory behavior. However, the sizes of the seminiferous tubules and renal sex segments, and the muscle fiber composition of the RPM, were not associated with copulation rates. Further, body size was not associated with the size of any of the reproductive structures investigated. The results of this study suggest that peripheral morphologies involved in the transfer of ejaculate may be more evolutionarily labile than internal structures involved in ejaculate production.

Morphology and structure evolution of metallic nanowire arrays prepared by die nanoimprinting

Metallic nanowire arrays （NWAs） possess wide application prospects due to their unique property, and the tailoring of NWAs＇ structure and morphology is of importance since it would significantly influence the per- formance of NWAs. In the present work, the morphology and structure evolution of the NWAs prepared by the newly developed die nanoimprinting technique has been investigated in detail. It was found that increasing pro- cessing temperature, time and pressure could increase the length of the nanowires and change the NWAs＇ morphol- ogy from monodispersed form to aggregated form. Increasing processing time and temperature within the supercooled liquid region would promote crystallization, while increasing processing pressure could suppress the crystallization. This work provided important insights into the structure and morphology evolution, and therefore, the tailoring of metallic NWAs prepared by die nanoimprinting through adjusting the process parameters.