S型规整填料的液泛特性及模型研究

用直径为0.5 m、填料高度为1 m的有机玻璃塔,在常温常压下以空气和水为介质,在不同的喷淋密度下测定S型规整填料的液泛性能,并将其液泛气速与CY型和SQ型规整填料进行了比较。实验结果表明,S型规整填料具有较大的液泛气速,S-800型填料液泛气速较CY-800和SQ-800平均提高了20.77%和15.34%。由规整填料层内流体的水力学理论关系式可推导得到S型填料的液泛气速模型,该模型的计算值与实验值的最大相对偏差均为3.09%,平均相对偏差为2.29%,可用来预测S型规整填料的液泛特性。     

6061铝合金搅拌摩擦焊接头性能研究

采用搅拌摩擦焊对6 mm厚6061-T6铝合金板在不同工艺参数下进行焊接。观察了接头的显微组织,研究了接头室温拉伸性能及晶间腐蚀性能,测试了接头腐蚀前后的显微硬度。结果表明:在搅拌头转速900r/min、焊接速度100 mm/min、焊后缓冷工艺下,可得到性能较好的接头,其抗拉强度可达到母材的74%。接头显微硬度呈现"W"型分布,存在明显的软化区,母材的硬度最高,热影响区的硬度最低。晶间腐蚀最严重的部位发生在焊核区,经腐蚀后接头硬度显著下降。     

纤维素助滤剂的预敷过滤性能

对高黏度物料加入纤维素助滤剂的预敷过滤性能进行了研究,说明不同的预敷条件对预敷层的过滤性能会有很大影响。通过改变预敷压力和浓度,对纤维素滤饼层的过滤比阻、可压缩性系数和孔隙率进行了研究。实验表明,纤维素预敷层的比阻随压力增加而增加,随浓度增加而减小;孔隙率随压力增加而减小,随浓度增加而增加;可压缩性系数随浓度增加而增加。纤维素助滤剂为中等可压缩性物料,孔隙率大。研究结果可为高黏度物料用纤维素预敷过滤的工程应用提供参考。     

预应力混凝土曲线连续箱梁桥支座布置研究

为避免预应力混凝土曲线连续箱梁桥在预应力、外部荷载作用下发生支座脱空的现象,以某互通匝道桥为典型工程,应用空间有限元法,在不同荷载、不同支座布置形式下,分析曲线箱梁桥的支座反力和位移,探讨合理的支座布置形式。结果表明:中间支座全部是墩梁固结的支座布置形式最不易     

DMFCs用SPEEK/SiOx-S复合质子交换膜

A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalized silica powder with sulfonic acid groups (SiOx-S) was added into the SPEEK matrix (DS 55.1%) to prepare SPEEK/ SiOx-S composite membranes. The decrease in both the swelling degree and the methanol permeability of the membranes was a dose-dependent result of addition of the SiOx-S powder. Pure SPEEK membrane swelled 52.6% at 80°C, whereas the SPEEK/SiOx-S (15%, by mass) membrane swelled only 27.3% at the same temperature. From room temperature to 80℃, all SPEEK/SPEEK/SiOx-S composite membranes had methanol permeability of about one order of magnitude lower than that of Nafion115. Compared with pure SPEEK membranes, the addition of the SiOx-S powder not only leads to higher proton conductivity, but also increases the dimensional stability at higher temperatures, and greater proton conductivity can be achieved at higher temperature. The SPEEK/SiOx-S (20%, by mass) membrane could withstand temperature up to 145°C, at which in 100% relative humidity (RH) its proton conductivity exceeded slightly that of Nafion115 membrane and reached 0.17 S•cm－1, while pure SPEEK mem-brane dissolved at 90°C. The SPEEK/SiOx-S composite membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.     

DMFCs用磺化聚醚醚酮/磺化酚酞型聚醚砜共混质子交换膜

A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly(ether sulfone) (SPES-C, DS 53.7%) is blended with the SPEEK matrix (DS 55.1%, 61.7%) to prepare SPEEK/SPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK (DS 61.7%) membrane dissolves completely in water at 70ºC, whereas the swelling degree of the SPEEK (DS 61.7%)/SPES-C (40%, by mass) membrane is 29.7% at 80ºC. From room temperature to 80ºC, the methanol permeability of all SPEEK (DS 55.1%)/SPES-C blend membranes is about one order of magnitude lower than that of Nafion®115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK (DS 55.1%)/SPES-C (40%, by mass) membrane can withstand temperatures up to 150ºC. The proton conductivity of SPEEK (DS 55.1%)/SPES-C (30%, by mass) membrane approaches 0.16 S•cm－1, matching that of Nafion115 at 140ºC and 100% RH, while pure SPEEK (DS 55.1%) membrane dissolves at 90ºC. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.     

番茄西瓜糖醋蒜的研制

以番茄、西瓜、新鲜大蒜为主要原料,辅以米醋、白砂糖调配,采用正交试验和感官评价确定了番茄西瓜糖醋蒜最佳配方为:番茄浆25%,西瓜浆25%,米醋150 g/L,白糖15%,食盐5%。此方法生产的成品蒜不仅减轻了蒜的辛辣味,且色、香味俱佳,是一种老少皆宜的健康调味食品。     

纳滤理论的研究进展

对非平衡热力学模型、溶解扩散模型和细孔模型进行了详细分析。纳滤膜分离过程是一个不可逆过程,其分离机理可以用非平衡热力学模型、溶解扩散模型、不完全溶解扩散模型、细孔模型、电荷模型(空间电荷模型和固定电荷模型)、静电排斥和立体阻碍模型,以及近年才提出DSPM模型和MS模型等来描述;并对纳滤的研究方向提出了展望。     

中小企业数字化转型与工业互联网关联关系研究

中小企业是推动国民经济发展的核心力量,亟须依托工业互联网等新一代信息技术,建立由政府引导的数字化转型模式,解决中小企业“不敢转、不能转、不会转”的问题。基于此,文章提出了“以面增量”“以点提质”和“点面结合”的转型策略。     

牡蛎抗菌肽Molluscidin的密码子优化、重组毕赤酵母表达及抑菌活性

目的:利用重组毕赤酵母高效表达抑菌活性较好的牡蛎抗菌肽Molluscidin.方法:按照毕赤酵母密码子偏好性优化合成牡蛎抗菌肽Molluscidin,利用生物信息学方法分析其基本理化性质,经EcoRⅠ和NotⅠ双酶切后与表达载体pPICZαA连接,构建重组质粒pPICZαA-CgMoCo,电转至毕赤酵母X-33,利用博...