中国造纸用精细化学品的现状和发展

我国造纸用精细化学品行业还很年轻,发展速度远远不能满足需要,在一定程度上影响和制约了造纸工业的发展。未来发展应密切结合国情开发生产系列化产品和“绿色新品种”,强化应用技术研究和售后服务,企业向集约化、专业化发展。     

Ultrasonic non-destructive on-line estimation of the tensile stiffness of a running paper web

A new method for measuring the elastic properties of paper on-line in a paper machine by using ultrasound has been developed. The unique feature of the method is that a continuous stochastic ultrasonic signal is used for measurements, which is generated by means of a dry friction between a running paper web and a rigidly fixed friction head. The signals from the web are picked up by an array of air-coupled ultrasonic receivers, which have no mechanical contact with the paper web. The ultrasound velocity in the web is obtained by means of the correlation processing. By using advanced digital signal processing, the tensile stiffness index (TSI) of the running web is determined. From the sensor we get the TSI values both in the machine direction and the cross-machine direction.The on-line ultrasonic sensors have been installed on two different paper machines for more than two years. This paper describes the background of the method, as well as some experiences and applications from two mill installations.     

Half-Lives and Gamma-Ray Energies of Short-Lived Molybdenum Isotopes

Short-lived molybdenum isotopes produced by the ²³⁶U(n, f) reaction were isolated by rapid paper electrophoretic technique. Gamma-ray spectra of the isolated molybdenum fraction were measured with high resolution Ge(Li) detector. The half-lives of ¹⁰³Mo (70±1 sec), ¹⁰⁴Mo (66±2 sec) and ¹⁰⁵Mo (30±3 and 40±5 sec) were determined by analyzing the genetic relationships of the known photopeaks of their technetium daughters. Decay analysis of observed photopeaks free from interference resulted in the detection of many new short-lived photopeaks with half-lives of 10–70 sec, and which were not relevant to technetium isotopes. These new photopeaks were ascribed to ^103-106Mo, based on examination of their decay behavior.     

面板内抽芯注射模设计

分析了带内抽芯板类塑件的成型工艺及主要的成型过程,说明内抽芯与外抽芯相比的优势,介绍了设计中需要注意的要点及模具装配时需要注意的问题。     

Model studies of migration from paper and board into fruit and vegetables and into Tenax™ as a food simulant

Four samples of paper and board (P/B) of a type used for packaging dry foods were subjected to migration tests using mushrooms, apples, potatoes and bananas, and using the polymeric powder Tenax? as a food simulant. The P/B samples contained only low levels of diisopropylnaphthalene (DiPN) and diisobutyl phthalate (DiBP) and so the experiments were conducted after impregnating the P/B with added model substances. These were o-xylene, acetophenone, dodecane, benzophenone, DiPN and DiBP. Migration levels depended strongly on the nature of the substance and on the nature of the food and much less on the characteristics of the P/B, except insofar as they affected the contact area – flexible papers giving more extensive contact with the food than thick rigid board. Migration into Tenax? was at least a factor of 10 higher than migration into the fresh fruit and vegetables. The food samples were placed in contact with the P/B and then overwrapped loosely with aluminium foil and so this correction factor will tend to be conservative compared with a more open storage of the packed foods. Washing, peeling or cooking the fruits and vegetables after contact with the P/B had a surprisingly small effect on contaminant levels in general, and no one processing step was effective in giving a significant reduction of all the types of chemicals studied. This was because either they had penetrated into the food (so resisting peeling), or were not freely water-soluble (so resisting washing) or were not particularly volatile (so resisting loss by evaporation during cooking).     

Shrunk multiline addressing method in a passive‐matrix‐driven liquid powder display

Abstract— A shrunk multiline addressing method (SMLA) in a passive‐matrix‐driven liquid powder display will be discussed. An algorithm to generate SMLA data that effectively reduces the number of scanning lines has been devised. The update time is reduced by 44.5% on average, and this reduction is maintained despite increased sizes of the images. The SMLA data generated by this algorithm is applied to e‐paper panels, thereby confirming the reduction in update time and that the image quality of the panels driven by SMLA is equal to that of conventionally driven ones.     

基于Author Ware的电子试卷的设计与实现

多媒体技术和网络技术的出现使计算机辅助教学取得了飞速的发展。文章首先解释了什么是Authorware,然后利用Authorware中的Quiz知识对象设计制作出一份考试试卷并详细讲解了其制作操作过程。     

Vulcanized paper for separation of alcohol aqueous solutions by pervaporation

Paper membranes made from vulcanized cellulose were used for the pervaporation (PV) of aqueous solutions containing methanol, ethanol, and isopropanol. It was noted that the vulcanized cellulose paper membranes (VCPM) could effectively separate alcohol and water from the mixture solutions. To observe the effect of the separation of alcohol aqueous mixtures, the permeation behavior of water and alcohol was examined by means of the separation factor and the permeation flux. The values of the permeation flux in the ethanol/water mixtures were found to vary from 6.2 kg/m²h to 2.1 kg/m²h, as the concentration of ethanol increased from 8 to 87 wt %, and the separation factor (α) changed from α = 2.6 to 6.6, respectively. This showed that the VCPM enhanced the separation of water and alcohol. The highest value observed for the permeation flux was 11 kg/m²h at 87 wt % of methanol concentration and the separation factor at this condition was 4.1. It was shown also that an efficient separation was obtained in the isopropanol/water mixture with a separation factor of 16.6. The contact angles of alcohol/water droplets on the VCPM were measured as well as the wettability of the membrane. There was a tendency of decrease for the contact angle, as the alcohol concentration decreased. This suggested that the solvent wettability decreased in high alcohol concentrations. It was concluded that a high permeabilitty of water through the VCPM resulted in the separation of alcohols and water in the PV process. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Fechner's "inner psychophysics."

Though psychologists are generally aware that Gustav Fechner introduced psychophysics and set down its essential methodology, most of them only know about the part that Fechner called “outer psychophysics.” In his classic publication of 1860, Fechner insisted that “inner psychophysics” was more important, yet this aspect of Fechner's work failed to receive any attention. The article reviews Fechner's presentation of inner psychophysics and suggests reasons why that part of his work was neglected and has been forgotten. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

福州平安大厦深基坑双层双圆环内支撑支护施工技术

介绍福州平安大厦３层地下室基坑支护采用２道双环支撑的施工方法及防止坑涌的技术措施。