注射成型薄壁制品的结晶度

简要概述了注射成型过程中的非等温结晶和2种计算结晶度的方法。结果表明，在注射模CAE开发中，用DSC测量是一种比较实用简便的计算结晶度的方法。     

林产化学加工学科的现况与发展前景

本文了介绍了并论述了林产化学加工学科所含的五个专业方向，木材化学加工工程，树木提取物化学工程，林产生物化工，木材保护与改性，林产化工装备与控制的研究内容，工业现状，存在问题与发展前景。     

Phase studies of pozzolanic stabilized calcium silicate hydrates at 180 °C

Phase studies of calcium silicate hydrates formed at elevated temperature and pressure have been well documented. At 180 °C, the initially formed amorphous calcium silicate gel [C-S-H] transforms into well-defined crystalline phases, the stability of which is primarily dependent on the C/S ratio in the CaO-SiO₂-H₂O system and the hydrothermal conditions. Hillebrandite [C₂SH], α-dicalcium silicate hydrate [α-C₂SH] and β-tricalcium silicate [β-C₆S₂H₃] are predominantly the stable phases in the lime-rich part of the CaO-SiO₂-H₂O system and are typically associated with high permeability and compressive strength retrogression. Gyrolite [C₂S₃H_~2], tobermorite [C₅S₆H₅], truscottite [C₇S₁₂H_~3] and xonotlite [C₆S₆H] have all been reported to coexist stably in aqueous solution with silica in the silica-rich part of the CaO-SiO₂-H₂O system.The addition of excess silica to the CaO-SiO₂-H₂O system is usually in the form of silicon dioxide [SiO₂], either as microsilica or quartz flour, which, in theory, should not affect the equilibrium chemistry. This has not been found to be the case, and metastable phases formed in the early stages of reaction modify the long-term stability and phase equilibrium. Pozzolanic materials that are predominantly alumino-silicates have also been investigated as a source of excess silica. Partial replacement of aluminum for silicon occurred, but had no apparent influence on the stability of the calcium silicate hydrates formed.     

Surface properties of surfactants derived from natural products. Part 1: Syntheses and structure/property relationships—Solubility and emulsification

Several novel and some previously known, mostly sugar-based, surfactants have been synthesized and some of their surface properties have been characterized and compared with those of commercial nonylphenol ethoxylates. The surfactant solubility in water, ethanol, and dodecane was studied. The properties of these compounds as emulsification agents in systems composed of the surfactant with water/isopropyl myristate, water/rapeseed oil, and water/dodecane are presented. The aqueous solubility of the surfactants follows the general trend expected from their hydrophilic-lipophilic balance according to Griffin (HLBG), but it is also clear that the nature of the headgroup and the structure of the nonpolar part affect the solubility in a manner not aptured in the standard HLBG concept. An ester or amine group as the connecting unit between the hydrophile and the hydrophobe produces a more water-soluble surfactant than the corresponding amide derivative. Some effective emulsifiers were found. For instance, the surfactants with a dehydroabietic nonpolar group appear to be promosing emulsifiers. Most sugar-based surfactants were able to form macroemulsions of up to around 2 wt/vol% of oil. The stability of many of these amulsions was very high, extending for months.     

影响建陶产品生命周期因素的分析与探讨

本文从建陶产品生命周期缩短的现象入手，应用产品生命周期理论和相关的数学模型，对建陶产品生命周期的各个影响因素进行了分析和探讨。     

Schistosome behavior in vitro

Schistosome adults attract each other in vitro and the attraction is chemically mediated. InSchistosoma mansoni adults, excretory-secretory (ES) products of worms of one sex attract worms of the opposite sex, and at least the lipophilic fraction is attractive. Intra- and interspecific attraction occurs inSchistosoma mansoni, S. japonicum, andS. haematobium adults. Current knowledge of schistosome behavior in vitro is reviewed.     

浅谈电子产品对儿童的影响及对策

在现代社会中,平板电脑、智能手机在人们日常生活的方方面面发挥着巨大的作用。通过分析电子产品在儿童和青少年的视力、身体发育、社交能力和学习能力等方面的负面影响,提出了加强亲子陪伴、合理引导控制等应对措施。     

甲醇工业发展方向及应用分析

介绍了甲醇的几种重要的下游产品,如甲醛、甲酸甲酯、甲胺等,提出应大力生产和发展甲醇下游产品,并进一步拓宽甲醇的应用领域,加快甲醇应用新技术的开发工作。     

Effect of retempering with superplasticizer admixtures on slump loss and compressive strength of concrete subjected to prolonged mixing

To have concrete possesses the specified engineering properties, its slump loss has to be compensated somehow at construction site so that concrete could be placed and compacted properly. Several attempts have been tried so far to render concrete workable at construction site including starting with a high initial slump at the stationary plant, or retempering with water and/or with chemical admixtures at construction site. In this investigation, ASTM C 494 Type F superplasticizer was used for retempering concrete to restore its initial slump. Concrete mixes having an initial slump of about 19 cm were prepared and subjected to prolonged mixing with different mixing duration such as 30, 60, 90, 120, and 150 min following an initial mixing of 5 min to ensure homogeneity. At the end of each mixing period, cube specimens of 15 cm were cast from concrete retempered to its initial slump level and tested at the age of 28 days for compressive strength. Results revealed that compared to the concrete retempered with water, those retempered with a superplasticizer admixture have yielded significantly higher strength regardless of the mixing duration.     

New Refractories Developed by the Ukrainian Research Institute of Refractories Named after A.S. Berezhnoy

The article gives an introduction to the Ukrainian Research Institute of Refractories and especially its R D and refractory products for the industries of iron and steel,nonferrous,glass and chemistry etc.