锦纶织物泡沫染色工艺参数的研究

采用泡沫体系对锦纶织物进行染色,研究酸性染料用量、发泡液温度对发泡性能的影响,染色工艺参数发泡比、汽蒸温度、汽蒸时间、汽蒸后织物含湿量对织物色深K/S值以及色牢度的影响。结果表明:泡沫体系中染料用量越大,发泡体积越小,半衰期越大;当发泡液温度为40℃时,综合泡沫性能最佳。发泡体系发泡比越大,织物色深K/S值越大;汽蒸后织物含湿量越大,K/S值越大;不同酸性染料的最佳汽蒸温度和汽蒸时间不尽相同。与常规浸染相比,泡沫染色可以达到更高的表观得色量,更高的耐皂洗褪色牢度,相同的耐皂洗沾色牢度和耐摩擦色牢度。

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.

Influence of subsequent curing on water sorptivity and pore structure of steam-cured concrete

Steam-cured condition is found to cause larger porosity and worse properties of concrete compared with normal curing condition. For the sake of seeking effective measurements to eliminate this bad effect of steam-cured condition on concrete, the water sorptivity and pore structure of steam-cured concretes exposed to different subsequent curing conditions were investigated after steam-curing treatment. The capillary absorption coefficient and porosity of the corresponding concretes were analyzed, and their mechanisms were also discussed. The results indicate that water sorptivity and pore structure of steam-cured concrete are greatly influenced by the curing condition used in subsequent ages. Exposure steam-cured concrete to air condition has an obviously bad effect on its properties and microstructures. Adopting subsequent curing of immersing steam-cured concrete into about 20℃ water after steam curing period can significantly decrease its capillary absorption coefficient and porosity. Steam-cured concrete with 7 d water curing has minimum capillary absorption coefficient and total porosity. Its water sorptivity is decreased by 23% compared with standard curing concrete and the porosity is 9.6% lower. Moreover, the corresponding gradient of water sorptivity and porosity of steam-cured concrete both decrease, thus mictostructure of concrete becomes more homogeneous.

Corncobs as Substrate for Oleaginous Yeast-Pretreatment via Steam Explosion and Hydrolysis

Corn cobs are a promising lignocellulosic substrate for the production of biofuels like bioethanol via conventional yeast or biodiesel via oleaginous yeast. Pretreatment of the substrate is essential for further hydrolysis and fermentation steps. This study focused on the steam explosion method as pretreatment. Therefore, different steam explosion severities were evaluated. The content of glucan, xylan and Klason lignin was examined. Xylan degraded with increasing severity from 412.7 g·kg-1 （untreated） to a minimum of 127.3 g-kg1 dry matter （190 ℃/30 min）. Glucan concentrations increased from 315.1 g·kg1 （untreated） to a maximum of 371.6 g·kg-1 dry matter （200 ℃/20 min）. For soluble lignin, an increase could be observed at rising severity, from 145.3 g·kg-l （untreated） to a maximum of 214.9 g·kg-1 dry matter （190 ℃/30 min）. Furthermore, the mass recovery was calculated. At harsher pretreatment conditions, a significant mass loss was observed, estimated by the ash content in the recovered dry matter. The lowest recovery rate was observed for SF = 4.13 （190 ℃/30 min） with 68.39%. The produced inhibitors were evaluated.

A Novel Method for Obtaining a Crack Tip Appropriate Multiaxiality Constant for Damage Mechanics

Many engineering components, such as power-plant steam pipes, aero-engine turbine discs, etc., operate under severe loading/temperature conditions. As a result, cracks can initiate and subsequently propagate over time due to creep. The Liu and Murakami＇s model has proven to be a useful tool for the prediction of creep crack growth under such conditions. Previously, experimental conditions used in obtaining the constant ofmultiaxiality, a, have not reflected the multiaxial severity of the stress state ahead of a crack tip. Therefore, the present study presents a novel method for interpolating crack growth data to obtain a.