中国传统工艺振兴语境下的工匠精神

目的针对目前国家大力保护非物质文化遗产、倡导传统工艺振兴的语境下,如何传承和发扬好工匠精神,以促进当前我国非遗的保护和传统手工艺的传承与发展。方法以文献考据的方式,详细论述我国历史上不同时期关于工匠和工匠精神的解读,从古代"工"或"匠"到现代"大师"的演变,以及数千年来我国工艺文化传统所凝结成的大匠气度和大师境界,即将技艺臻于极致,将作品琢至完美的"工于技艺,匠心独运"的当代工匠精神。结论传承和发扬工匠精神须从政府加强指导、社会全力推崇、艺人珍视声誉等几方面形成合力,从而推动我国传统工艺行业的健康发展。     

The accuracy of calculation of orbits of best approach

A new formulation and solution of the problem of calculation of orbits of best approach is discussed. A qualitatively analytical approach to the organization of observations of the motion of artificial Earth satellites is used that makes it possible to calculate and to allow for optimal celestial-mechanics conditions, and to eliminate the effect of systematic observation errors, the effect of the Earth's gravitational field, and other regular perturbations on the solution accuracy.Translated from Izmeritel'naya Tekhnika, No. 6, pp. 28–29, June, 1993.     

Assessment of the cause of cracking of hydraulic hose clamps

The aim of this study was to determine the cause of failure of the shells of hydraulic hose crimped fittings. For the purpose of examination the damaged crimped shells, undamaged crimped shells and shells prior to crimping were used. Fractographic and metallographic analysis, including chemical microanalysis of inclusions, were performed to determine the cause of failure. For this investigation, optical and scanning electron microscopes and hardness measurement were used. Damaged crimped shells contained higher amount of inclusions compared to undamaged crimped shells and substantially differed in microstructure and hardness. Furthermore, different geometry of the cross section at outer edge containing more effective stress concentrators was observed on failed crimped shells. Based on microstructural observation in cross section, hardness measurements and analysis of inclusions, the conclusion is that cracking of the shells occurred mainly due to deviations in the manufacturing process, combined with lower quality of shell material. Modifications to the technology were suggested to prevent this kind of failure.     

一起空分设备主换热器过冷故障的分析

在KDON-6000/3500型空分设备调试过程中,由于经验不足、操作不当,造成主换热器发生过冷故障。停运一台膨胀机,采用液氧返充操作使空分设备恢复正常工况。介绍故障发生经过和原因分析过程,以及防止同类故障再次发生的预防措施。     

Analysis of the effect of pressure on compression moulding of UHMWPE

Ultra-high molecular weight polyethylene (UHMWPE) powder is effectively processed by compression moulding due to its very high melt viscosity. Compression moulding involves application of temperature and pressure as a function of time. The pressure applied during processing has a significant influence on the part properties. The effect of pressure applied during compression moulding was studied by moulding parts at different pressures. Increase in the applied pressure causes increase in the melting and recrystallization temperatures. An increase in the pressure applied at the melt temperature (140°C) from 7.8 MPa to 15.6 MPa caused the crystallinity to increase from 54% to 61%, the stiffness of the moulded part to increase from 257 MPa to 435 MPa and oxidative index to increase from 0.055 to 0.059. Further increase in the pressure applied at the melt to 23 MPa caused the crystallinity to fall to 49%, the modulus to reduce significantly to 302 MPa and the oxidative index to change to 0.063. Increase in the pressure applied at the recrystallization temperature (91°C) from 38 MPa to 78 MPa increased the crystallinity from 54% to 65%, increased the modulus from 257 MPa to 279 MPa and increased the oxidative index from 0.055 to 0.065. Further increase in the applied pressure to 97 MPa, caused the crystallinity to drop slightly to 61% the modulus to reduce to 269 MPa, and the oxidative index to reduce to 0.057. The experiments showed that for obtaining maximum crystallinity and stiffness, the applied pressure should be within a narrow range. The highest recrystallization pressure (97 MPa) indicated the formation of extended-chain crystals in addition to the chain-folded crystals. The change in pressure applied at the melt temperature had a significantly greater effect on Young's modulus, as compared to change in pressure applied at the recrystallization temperature. Fourier transform–infrared spectroscopy analysis of the samples moulded at different pressures revealed that the increase in crystallinity and stiffness was accompanied by increase in oxidation within the part. By filling the die in a nitrogen atmosphere instead of air, the oxidation level in the moulded parts was reduced by almost 60%, without adversely affecting the crystallinity and the modulus. © 1998 Chapman & Hall     

Inverse Problem of Evaluation of the Coefficient of Friction of Layers According to the Data of Measurements of the Surface Displacements

We consider a one-dimensional model of friction contact of two layers of different nature. The lower surface of the first layer is elastically fixed and the second layer is pressed to the upper surface of the first layer and moves along this surface with variable velocity. As a result of friction, heat is produced on the contact surface according to the Amonton's law. For known boundary and initial conditions, we pose the problem of evaluation of the friction coefficient and the intensity of friction heat flux according to given values of the vertical displacements of the upper surface of the second layer. The posed problem is reduced to the inverse contact problem of thermoelasticity described by the Volterra integral equation of the first kind. The solution of the problem obtained by the method of averaging of functional corrections enables us to study the time behavior of the indicated quantities for the entire period of interaction of the bodies and establish the dependence of the friction coefficient on the basic parameters of the process (sliding velocity, contact pressure, and temperature of the contact surface). The solution of the direct contact problem of thermoelasticity is used to perform the numerical verification of the proposed method for the solution of the inverse problem.     

石油元素的文化符号在文具产品设计中的应用

目的 从石油文化特色出发,提炼视觉符号用于文具产品设计中,赋予其人文情怀,传承石油文化,发扬石油精神,唤起消费者的兴趣。方法 以“石油元素”的视觉符号提取为切入点,从造型、色彩、材质3个视角,物质、造型、精神3个层面,深入剖析其形象符号,提炼其中典型的视觉要素,将其创造性地应用于文具用品设计中,并形成系列。设计中注重造型元素和风格的统一,同时也考虑到人体工学与需求、功能、材料、颜色、美感等的协调。结论 对设计要素的创新应用,是构建特色城市外在形象和内在文化的重要媒介,“石油元素”的提炼和再设计,是需要在深入研究石油文化内涵的基础上,融入恰当的设计思维和表现形式,为具有石油特色的城市的纪念品设计提供一些思路。     

A new method of measurement of the different types of noisealtering the output signal of oscillators

Oscillator noise is generally modeled by a power law spectral density. Thus it is possible to characterize different noise sources, each of them corresponding to a particular power law. The measurement of the contribution of these sources is necessary to know their origin and to remedy these causes in order to improve oscillator performance. Usually, an estimation of the different types of noise present in a signal is obtained by using a variance. However, the sensitivity of these variances differs for each type of noise and then limits this method. On the other hand, the use of several variances, each of them more sensitive to one type of noise, permits one to notably improve the measurement accuracy. The method suggested here uses as many different variances as there are types of noise to measure. The improvement of measurement accuracy of the noise coefficient is discussed in this paper     

Prediction of the Viscosity of Liquid Mixtures

This paper describes the application of the theoretically based scheme of Vesovic and Wakeham, modified by making use of the hard-sphere model of Dymond and Assael, to the prediction of the viscosity of liquid mixtures. The purpose of the paper is to examine this scheme in more detail than earlier to find out in what circumstances it works well and when it fails. Hence, the scheme is employed to predict, for the first time, the viscosity of a wide range of mixtures of quite disparate liquids from groups of hydrocarbons, through combinations of alcohols and hydrocarbons, to halogenated refrigerants. It is shown that, in all cases, provided that the mass ratio of the pure components is close to unity, the predictions show excellent agreement with experiment.     

过冷器污氮通道堵塞的排除

由于过冷器污氮通道被珠光砂堵塞,12000 m3/h空分设备的氧气产量不能达到设计值,由于后续生产系统需要无法停车检修,只能采取临时措施保持氧气产量的正常供应,最终通过扒砂并更换过冷器使故障得到彻底排除。介绍故障发生时空分设备技术参数的变化情况和原因分析过程。     

Symmetries of cross-polarization diffraction coefficients of gratings

In a recent paper [J. Opt. Soc. Am. A 16, 1108 (1999)] Logofatu et al. demonstrated by experimental and numerical evidence that the 0th-order cross-polarization (s to p and p to s) reflection coefficients of isotropic, symmetrical, surface-relief gratings in conical mount are identical. Here an analytical proof is given to show that the observed identity is merely a manifestation of the electromagnetic reciprocity theorem for the 0th-order diffraction of symmetrical gratings. The above result is further generalized to bianisotropic gratings, to the 0th-order cross-polarization transmission coefficients, and to the mth-order reflection and transmission coefficients when the wave vector of the incident plane wave and the negative of the wave vector of the mth reflected order are symmetrical with respect to the plane perpendicular to the grating grooves.     

等离子喷涂制备钢质涂布刮刀陶瓷涂层

以涂层平面度为评价标准,通过正交试验优化等离子喷涂工艺参数,在普通蓝钢刮刀上制备Al2O3-20%TiO2涂层,并对涂层的显微形貌、结合强度和耐磨性进行了研究.结果表明:弧电流550 A,喷涂距离100 mm,走枪速度0.8 m/s时等离子喷涂制备的Al2O3-20%TiO2涂层平面度最优;涂层具有良好的结合强度和耐磨性,结合强度大于30 MPa;磨粒磨损机理为切削和脆性断裂或脱落磨损.     

汽车橡胶密封条挤出口模结构分析及其实验验证

首先通过分析橡胶材料流变实验数据,确定采用Bird-Carreau本构模型;然后应用Polyflow软件对某实际EPDM橡胶密封条产品挤出过程中挤出口模流道结构对挤出的影响进行了有限元分析。结果表明,口模流道某些部位(如窄缝区域)进行适当的加宽有利于使挤出速度及熔体压力分布更均匀,挤出产品形状和实际形状更接近。     

Study of the influence of the pH media dissolution, degree of polymerization, and degree of swelling of the polymers on the mechanism of release of diltiazem from matrices based on mixtures of chitosan/alginate

The dissolution profiles of formulations based on mixtures of chitosan/alginate depend on the pH. It is possible to distinguish two processes: (a) a fast kinetic drug release up to 180 min, where the pH value changes from 1.17 to 2.21 and the drug released is controlled by the degree of polymerization and the quantity of chitosan in the formulation; (b) a low kinetic drug release between 210 and 480 min, where the pH value changes from 5.52 to 8.72 and the drug release from the matrix is controlled by the interpolymeric complex. In all formulations the order of release, according to Peppas's model in the range of fast kinetic drug release, was between 0.5 and 1.0. The mechanism of release was non-fickian diffusion, which corresponds to a coupling mechanism of diffusion and relaxation of the polymer.     

薄板烘丝机干头干尾量改进研究

目的 为了解决烟丝烘干过程中出现干头干尾过多,造成后续加工浪费的问题,在分析现有文献和现有设备的基础上,对烘丝工艺进行改进。方法 通过对干头干尾产生的原因和来料水分与烘丝温度的关系分析,采用抗滞后MFA控制器实现对温度的控制,并对现有烘丝设备蒸汽、水管路系统进行改造,对料头和料尾部分增加了水、压空双介质喷嘴来增加湿度,以提高烟丝的利用率。结果 经过不断的调试与试运行,使得每批次干头干尾量由原本的0.624%减少为0.16%。结论 通过温度控制改进和加装增湿装置来减少干头干尾量,将项目投入运行。实际运行结果表明,该系统运行可靠,干头干尾量得到明显降低,减少了原材料的浪费,提高了烟丝利用率和卷烟产量。     

Intercomparison of Measurements of the Thermophysical Properties of Polymethyl Methacrylate

Results of an intercomparison of measurements of thermal conductivity, thermal diffusivity, specific heat capacity, and density of polymethyl methacrylate (PMMA) in the temperature range between –70°C and +80°C are presented. The purpose of this comparison is to investigate the variability of the results among guarded hot-plate (GHP) and guarded heat-flow meter (GHF) techniques on the one hand and among GHP/GHF and other measuring instruments on the other. The primary objectives are to characterize the material properties mentioned and to quantify the effects of thermal contact resistances and temperature measurements. With regard to future use of PMMA as a reference material, reference data for the thermal conductivity are derived.     

Formulation of the latent heat of fusion of ice in aqueous solution

A calculation method to define the latent heat of fusion of ice in aqueous solution in the situation of the variation in the ice packing factor being infinitesimal is proposed. The calculation of the latent heat considers the effects of dilution and freezing-point depression, and the latent heat was calculated for five actual solutions, ethanol, ethylene glycol, propylene glycol, NaCl and NaNO3 solutions. Additionally, experiments in which ice was added to the five solutions were conducted to compare with the results of the calculations. Differential scanning calorimetry analysis was performed and the measurements and calculated values compared with respect to the specific enthalpy of the ice/solution mixture. Finally, since the values obtained by the measurements and calculations are in good agreement, the calculating method proposed in this study has proven to be adequate.     

Comparison of relative signal-to-noise ratios of different classes of imaging spectrometer

The continued development of new and fundamentally different classes of imaging spectrometer has increased both the scope and the complexity of comparisons of their relative signal-to-noise ratios. Although the throughput and multiplex advantages of Fourier-transform spectrometers were established in the early 1950s, the application of this terminology to imaging spectrometers is often ambiguous and has led to some confusion and debate. For comparisons of signal-collection abilities to be useful to a system designer, they must be based on identical requirements and constraints. We present unambiguous definitions of terminology for application to imaging spectrometers and comparisons of signal-collection abilities and signal-to-noise-ratios on a basis that is useful to a systems designer and inclusive of six fundamentally different classes (both traditional and novel) of imaging spectrometers.