惰性粒子对水沸腾传热强化的实验研究

通过加入不同种类和体积分率的惰性粒子,在垂直管中进行了水的流动沸腾传热实验,研究了三相流沸腾传热特性。实验中预先对水加热,采用了沸点进料。实验发现,传热膜系数随热通量、液体流量的增加及粒子体积分率的增大而增加。对于不同粒子,这种变化趋势比较一致,但不同粒子对沸腾传热的强化效果不同。实验结果表明:由于固体粒子的存在,强化了沸腾传热,三相流沸腾传热系数是相同条件下汽液二相流沸腾传热系数的1.3—1.7倍。     

硅酸盐粘土矿物的晶体结构与陶瓷减水剂的解凝机理

从泥浆微粒表面的ζ电位、粘土矿物的晶体结构以及陶瓷减水剂的解凝机理出发,说明如何根据制浆中所用粘土矿物的类型选择不同类型的减水剂,从而提高减水剂的使用性能。说明了粘土矿物种类与减水剂选择之间的关系,从而为在生产中合理、正确地选择减水剂以及开发新型减水剂提供理论依据。     

浅谈高温泥绘在现代陶瓷装饰中的表现

现代陶瓷装饰在材料语言方面相对于传统的种种突破,体现了现代人的审美要求。高温泥绘,吸收了古人所留下的丰富视觉遗产,其艺术效果独特,表现形式丰富多彩,在陶瓷装饰领域独树一帜,并具有不可彰显的魅力。     

几种新粘土原料在高强度电瓷中的应用

通过对几种粘土原料的比较,确定新配方中采用介休洗泥和青草岭洗泥,并采用0.060 mm筛孔径（250目）的细矾土,使得新配方具有良好的工艺性能,瓷材料弯曲强度得到了提高。     

邯郸粉质粘土固结不排水试验归一化性状分析

为了得到土的强度和变形之间的有机统一关系,反映区域性土的本构关系实验参数,本文根据归一化幂因子理论,从围压和平均固结压力两个方面论述了土的归一化理论,通过对邯郸粉质粘土的固结不排水三轴试验,得到了土的应力应变关系曲线,在此基础上用两种归一化方法分析了邯郸粉质粘土的性状,得到了归一化参数,为邯郸粉质粘土的本构关系研究提出了基本参数,可用于岩土工程理论与应用分析。     

Impact of retention on trans‐column velocity biases in packed columns

The heights equivalent to a theoretical plate of a weakly and strongly retained compounds were measured on two packed columns having different average mesopore sizes. The measurements were carried out in two different cases, with access to the mesopores by the sample molecules blocked (filled with n‐nonane) or not. The experimental results demonstrate that the eddy dispersion terms of both columns are significantly smaller for porous than for nonporous particles. Two simultaneous phenomena explain this observation. First, packed columns are radially heterogeneous which causes significant trans‐column velocity biases warping the bands. Second, radial dispersion contributes to mass transfer across the column, relaxing the radial concentration gradients that are caused by these velocity biases. The impact of these biases is minimized when the pores of the particles are not blocked; it decreases with increasing residence time and radial dispersion coefficient of the solutes. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Stiffening of Polycarbonate by Addition of a Highly Dispersed and Fibrillated Amorphous Polyamide‐Based Nanocomposite

Ternary systems consisting of blends of polycarbonate (PC) from bisphenol A and minority amounts of an amorphous polyamide reinforced with organically modified nanoclay (naPA), were obtained in the melt state. The nanoclay was widely exfoliated inside the dispersed naPA phase. The dispersed phase exhibited a very fine size (up to 0.36 µm), indicating compatibilization. Compatibilization was attributed to interactions between the aPA and the PC. The nanocomposite showed a lower compatibility than their corresponding blends. This lower compatibility of the nanocomposite was attributed to a hindrance of the interaction by the migrated surfactant of the organoclay. The presence of fibrillation in conjunction with a dispersed nanoclay resulted in additive enhancing effects on the modulus and yield stress. This led to modulus increases up to 46% with respect to that of the neat matrix upon the addition of 25% naPA‐10. Besides exhibiting these remarkable modulus values, these systems show an elongation at break similar to that of the neat PC matrix.

     

不同产地凹凸棒粘土合成4A分子筛的对比研究

以江苏盱眙和甘肃临泽凹凸棒粘土为原料,采用水热合成的方法,通过正交实验对合成分子筛的工艺进行了优化研究。实验表明,最佳工艺条件为:硅铝比为2∶1,碱硅比为1.5∶1,水碱比为40∶1,合成时间为6 h,所得产品钙交换量为357.5 mg CaCO3/g和350.5 mg CaCO3/g。合成出的产品通过SEM,IR,XRD,显微镜等检测,表明为性能良好的4A分子筛。经比较得出,不同产地的凹凸棒粘土均可合成出的4A分子筛,无需脱铁漂白工艺,其钙交换量和晶形完整度均高于相关文献。     

高凝胶强度吸水树脂的性能及在雨水处理中的应用

利用杭锦土合成了一种凝胶强度较大的吸水树脂,并将其用来处理雨水,考察了树脂添加量、处理时间、雨水的pH等因素对处理效果的影响;此外还利用该吸水树脂制成了强度较高的保水砖,研究了吸水树脂的添加量对保水砖失水的影响。试验结果表明:杭锦土能成功地接枝吸水树脂;加入杭锦土的吸水树脂,其凝胶强度明显提高;高凝胶强度吸水树脂能较好去除雨水中的主要污染物,100 mL雨水在pH值为7~8、树脂投加量为1 g左右、吸附时间为10 min左右时的处理效果较好;含10%吸水树脂的生态砖,其保水性能较好,所制保水砖的其他性能达到JC 943—2004标准。     

改性凹凸棒石粘土的制备及其对印染废水的处理效果

以凹凸棒石粘土为原料,采用三氯化铝（AlCl3）对凹凸棒石粘土进行改性,探讨了改性凹凸棒石粘土投量、pH值、吸附时间对处理效果的影响。结果表明：改性凹凸棒石粘土投加浓度为50g／L,吸附时间为40min,pH值=3时,印染废水的脱色率可达98％;该方法具有处理效果好,操作简单等优点;热再生是凹凸棒石粘土最好的再生方法。