改善壁龛的建筑热工条件

在我国严寒地区，由于砖混结构住宅和公用建筑物的外墙采用490mm厚的红砖墙，为了增加室内空间，一般都将采暖系统的散热器安装在壁龛内。由于外墙设置壁龛后，墙体厚度由490mm变为370mm，这样会使采暖耗热量增加6％。为了建筑节能，改善壁龛的建筑热工条件是十分必要的。通过对某公用建筑物标准层典型房间的热工测试和理论计算，在壁龛的内表面镶贴保温层可大大改善壁龛的建筑热工条件，从而达到节能的目的。

隧道室的热工特性及其最佳热工条件的确定

烧成陶瓷用隧道窑的热工特性直接关系到焙烧制品的产质量及能量消耗的高低.且隧道窑是机械、物理化学和热工过程的组合,而燃料燃烧和传热过程又有其本身的规律与特点.为此,寻求隧道窑最佳热工条件必与隧道窑的热工特性有关.从隧道窑的有关热工特性指标出发,利用生产数据迅速求取其具体情况下的最佳操作条件以不断降低能耗是陶瓷生产继续努力的方向.

火力发电厂凝汽汽轮机的热工检测与控制技术条件标准修编探讨

在对DL/T 590-1996号标准《火力发电厂固定式发电用凝汽汽轮机的热工检测控制技术导则》进行修订的过程中,笔者结合现场的实际情况和工作经验,以及对法律、标准的理解,在设备的选型、安装、调试等方面,对该标准的修编提出了自己的看法。

对地下空间进行开发利用的研究

针对当前城市化进程中出现的土地资源不足、环境不断恶化的情况,提出了开发地下空间、发展地下建筑的重要策略;分析了土壤的物理性能、热工条件以及对地下空间的需求量,并用一个具体的地下空间利用的设计方案来论证开发地下空间的必要性和可行性。分析表明,开发地下空间从可持续发展的角度为城市发展指出了一条新途径。

Regeneration of waste activated carbon after extracting gold with steam under microwave heating:Optimization using response surface methodology

The technology that waste activated carbon after extracting gold is regenerated with steam under microwave heating was studied. The influence of the activation temperature, activation duration and steam flow rate on iodine adsorption value and regeneration yield of activated carbon was investigated. The response surface methodology （RSM） technique was utilized to optimize the process conditions. The optimum conditions for the preparation of activated carbon are identified to be activation temperature of 831 ℃, activation duration of 40 min and steam flow rate of 2.67 mL/min. The optimum conditions result in an activated carbon with an iodine number of 1048 mg/g and a yield of 40%, and the BET surface area evaluated using nitrogen adsorption isotherm is 1493 m2/g, with total pore volume of 1.242 cm3/g. And the pore structure of activated carbon regenerated is mainly composed of micropores and a small amount of mesopores.

Isothermal and nonisothermal crystallization kinetics of bio-sourced nylon 69

Bio-sourced nylon 69,one of promising engineering plastics,has a great potential in developing sustainable technology and various commercial applications.Isothermal and nonisothermal crystallization kinetics of nylon 69 is a base to optimize the process conditions and establish the structure–property correlations for nylon 69,and it is also highly bene ficial for successful applications of nylon products in industry.Isothermal and nonisothermal crystallization kinetics has been investigated by differential scanning calorimetry for nylon 69,bio-sourced even–odd nylon.The isothermal crystallization kinetics has been analyzed by the Avrami equation,the calculated Avrami exponent at various crystallization temperatures falls into the range of 2.28 and 2.86.In addition,the Avrami equation modi fied by Jeziorny and the equation suggested by Mo have been adopted to study the nonisothermal crystallization.The activation energies for isothermal and nonisothermal crystallization have also been determined.The study demonstrates that the crystallization model of nylon 69 might be a twodimensional(circular)growth at both isothermal and nonisothermal crystallization conditions.Furthermore,the value of the crystallization rate parameter(K)decreases signi ficantly but the crystallization half-time(t1/2)increases with the increase of the isothermal crystallization temperature.To nonisothermal crystallization,the crystallization rate increases as the cooling rate increases according to the analysis of Jeziorny's theory.The results of Mo's theory suggest that a faster cooling rate is required to reach a higher relative degree of crystallinity in a unit of time,and crystallization rate decreases when the relative degree of crystallinity increases at nonisothermal crystallization conditions.

Utilization Starch of Avocado Seed （Persea Americana Mill.） as a Raw Material for Dextrin

Starch ofavocado seeds can be used as an alternative source of starch because it contains 80.1% starch. Natural starch can be made into a modified starch, for example dextrin. Dextrin can be made by using acid or enzyme hydrolysis. The purposes of this research were determine the concentration of hydrochloric acid （HCl）, the temperature and heating timein the optimum process of hydrolysis of starch into dextrin and to determine the quality of the resulting product dextrin terms of Indonesian National Standard 01-2593-1992. The methode was used in this research is hydrolisis with hydrochloric acid （HCl）. The results processing into starch avocado seed yield is 23.15%. HCl concentration, temperature and heating time significantly affect the value of dextrose equivalent （DE）, viscosity and part soluble in cold water. There is interaction between HCl concentration, temperature and heating time on the value of DE, viscosity and part soluble in cold water. Optimum conditions of process was obtained at a concentration of 0.15 N HCl, 30 minutes heating time and heating temperature of 90 ℃. Dextrose equivalent （DE） value is 19.61%. The value of solubility in cold water is 90.19%. Viscosity value is 1.61 ° E. Dextrin is not accordance with the standards of quality parameters Indonesian National Standard 01-2593-1992. Dextrin produced should be applied to non-food industry.