论张家川县农村剩余劳动力的转移

农村剩余劳动力转移是发展劳务经济,落实科学发展观,构建社会主义和谐社会的重要内容。借助劳动时间的测算方法,估算出张家川县农村有剩余劳动力5.23万人需要转移;同时分析了张家川县农村剩余劳动力转移的兼业性、盲目性、低层次性等特点及其劳动力在转移过程中影响因素;在分析和调查的基础上提出了对农村剩余劳动力进行合理、有序转移的途径。     

电力设备制造外包供方的评价与选择

利用过程方法对电力设备制造企业的外包运作过程和资源风险进行了分析．根据组织外包过程的绩效目标,在识别并分析外包供方运作资源的基础上,建立了电力设备制造外包供方评价指标体系．利用主成分分析法,构建了电力设备制造外包供方的评价模型．以河南省电力装备制造企业的外包过程为对象进行了实证研究,证明了本方法的有效性,为组织规避外包...     

隧道埋深及开挖方法对于二衬支护时机的影响

为了研究隧道埋深和施工方法对二衬支护时机的影响,以广梧高速公路牛车顶隧道为工程背景,建立数值计算模型,分别改变隧道埋深和施工方法,得到相应的隧道二衬支护时机.结果表明：通过数值计算,可定量得到二衬及掌子面之间的允许距离和埋深的关系;当埋深较小时,二衬与掌子面的允许距离随着埋深的增加而增加;当埋深超过某一限值时,隧道二衬与掌子面的允许距离基本不变;开挖工法对二衬与掌子面间的允许距离影响比较显著,而对仰拱与掌子面的允许距离影响很小.随着开挖断面分部的增加,开挖对围岩的扰动减小,因而可以适当延缓构筑二衬时机.若选取Ⅲ级围岩中的全断面开挖法作为参考基准,则围岩中二衬与掌子面的允许距离将由于选择不同工法需进行修正,相应的修正值为：全断面法1.0,上下台阶法和中隔壁法均为1.5.     

高职计算机实践课与“任务驱动”教学

高职计算机实践课程具有较强的实践性、应用性。基于这一特点,"问题(任务)驱动"是一种将传统教学方式转变为以解决问题、完成任务为主的多维互动式的教学理念;采用实际生活中的典型案例开头(提出问题、明确目标),逐渐展开(分析解决问题),将知识点融入任务之中,完成任务的同时又掌握相应的基本知识。是将再现式教学转变为探究式学习的一种方式。     

Toward a unified framework for the derivation of breakage functions based on the statistical theory of turbulence

The evolution of droplet or bubble size distribution in turbulent flow is of great significance in a variety of technological fields. Modeling this evolution by employing a population balance approach requires knowledge of the so-called breakage functions (rate and kernel). Over the years, a large number of phenomenological breakage functions with various degrees of sophistication have been proposed in the literature. Among them, those based on the statistical theory of turbulence are of particular interest, in that they attempt to take into account the structure of the flow field responsible for breakage. The purpose of the present work is to present a unified framework for developing this type of breakage functions and to show how existing models can be derived in a systematic and consistent way. The key parameters in this modeling approach are identified, which have to be determined by comparison with experimental data. It is also shown that the breakage functions, obtained within the framework presented here, lead to predictions of a droplet size evolution whose main features are consistent with experimental observations. It is suggested that this framework is an important step toward the development of a standard approach for modeling droplet size evolution in turbulent flow.     

乳胶涂料中填料粒径测定与分散剂的选择

介绍了重力沉降法和容量沉降法两种测定乳胶涂料中填料粒径的方法。通过比较粉体粒径结果显示：沉降法比激光法更形象直观，更能代表体系粒径真实情况。以滑石粉、重钙、轻钙粉体为基准，采用不同用量、不同类型的分散剂的容量沉降法进行比较得出：用容量沉降法能定量地对分散剂性能做出评价。     

Fractional partial differential equation denoising models for texture image

In this paper,a set of fractional partial differential equations based on fractional total variation and fractional steepest descent approach are proposed to address the problem of traditional drawbacks of PM and ROF multi-scale denoising for texture image.By extending Green,Gauss,Stokes and Euler-Lagrange formulas to fractional field,we can find that the integer formulas are just their special case of fractional ones.In order to improve the denoising capability,we proposed 4 fractional partial differential equation based multiscale denoising models,and then discussed their stabilities and convergence rate.Theoretic deduction and experimental evaluation demonstrate the stability and astringency of fractional steepest descent approach,and fractional nonlinearly multi-scale denoising capability and best value of parameters are discussed also.The experiments results prove that the ability for preserving high-frequency edge and complex texture information of the proposed denoising models are obviously superior to traditional integral based algorithms,especially for texture detail rich images.     

Theoretical assessment of the catalytic (Pt/TiO2) oxidation of formaldehyde at ambient temperature

A recent article [C. Zhang, H. He, K. Tanaka, Catal. Commun. 6 (2005) 211] investigates the use of a Pt/TiO₂ catalyst for the oxidation of formaldehyde. The findings demonstrate nearly complete oxidation at ambient temperature (25 °C) for values of the surface velocity in the range 5–10 × 10⁴ h⁻¹ and a 45% destruction when using a surface velocity of 20 × 10⁴ h⁻¹.In the present communication, this oxidation was assessed by theoretical considerations of the reaction kinetics. The destruction efficiency was predicted using a first-order reaction rate expression, combined with different theoretical or semi-empirical equations for the intrinsic reaction rate constant. Predicted and experimental data are in fair agreement, thus validating the theoretical approach and confirming the experimental results.     

Solid polymer electrolytes. XI. Preparation,characterization and ionic conductivity of new plasticized polymer electrolytes based on chemical‐covalent polyether–siloxane hybrids

A new hybrid polymer electrolyte system based on chemical‐covalent polyether and siloxane phases is designed and prepared via the sol–gel approach and epoxide crosslinking. FT‐IR, ¹³C solid‐state NMR, and thermal analysis (differential scanning calorimetry (DSC) and TGA) are used to characterize the structure of these hybrids. These hybrid films are immersed into the liquid electrolyte (1M LiClO₄/propylene carbonate) to form plasticized polymer electrolytes. The effects of hybrid composition, liquid electrolyte content, and temperature on the ionic conductivity of hybrid electrolytes are investigated and discussed. DSC traces demonstrate the presence of two second‐order transitions for all the samples and show a significant change in the thermal events with the amount of absorbed LiClO₄/PC content. TGA results indicate these hybrid networks with excellent thermal stability. The EDS‐0.5 sample with a 75 wt % liquid electrolyte exhibits the ionic conductivity of 5.3 × 10^?3 S cm^?1 at 95°C and 1.4 × 10^?3 S cm^?1 at 15°C, in which the film shows homogenous and good mechanical strength as well as good chemical stability. In the plot of ionic conductivity and composition for these hybrids containing 45 wt % liquid electrolyte, the conductivity shows a maximum value corresponding to the sample with the weight ratio of GPTMS/PEGDE of 0.1. These obtained results are correlated and used to interpret the ion conduction behavior within the hybrid networks. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1000–1007, 2006