模板法合成有序多孔材料研究进展

模板合成技术是制备有序多孔材料的有效手段，是一种生物模拟合成材料的方法，本文综述了制备有序多孔材料的方法。模板种类及其研究进展。     

多孔微珠用于制备低密度BMC材料

采用多孔微珠为填料制备了不饱和聚酯低密度团状模塑料(BMC)。选取多孔微珠的粒径及掺量,短切玻璃纤维的长度及掺量为4因素,设计L16(44)正交试验,并结合示差扫描量热法(DSC)和扫描电镜(SEM)对复合体系的增强机理进行了研究。结果表明,制备轻质BMC材料的最佳条件为:多孔微珠的粒径<0.710 mm,掺量4%,短切玻纤长度6 mm,掺量30%,此时制得BMC材料密度为1.314 g/cm3,弯曲强度为81.50 MPa,满足国标GB/T 23641—2009对BMC弯曲强度的要求(≥80 MPa)。多孔微珠的蜂窝壁对树脂的固化起到了阻碍作用,固化时间延长,放热不完全,同时多孔微珠的填充使得树脂基体的应力分散不均,样品的表观密度和弯曲强度降低。     

模拟宫腔液体积对Cu／LDPE多孔复合材料节育器的铜离子释放速率的影响

采用溶液分析法测定含铜宫内节育器（Cu-IUDs）的Cu^2＋释放速率时,所使用的模拟宫腔液（SUS）的体积远远大于人体宫腔液的实际体积,因此推算IUDs在体内宫腔液中的Cu^2＋释放速率时需要考虑SUS体积的影响。作者制备了两种不同孔隙度的Cu／LDPE多孔复合材料IUDs,测定了它们在不同体积SUS中的Cu^2＋释放速率．探讨了SUS体积对Cu^2＋释放速率的影响规律,并拟合出了释放初期和释放稳定期SUS体积与SUS中Cu^2＋浓度之间的关系式。结果发现,在释放初期,SUS体积对Cu^2＋释放速率影响不大;而在释放稳定期．SUS体积对Cu^2＋释放速率影响很大．SUS体积越大。Cu^2＋释放速率越快。     

面向气体分离膜应用的多孔陶瓷基体研究

在众多基体材料中,多孔陶瓷由于化学和热稳定性较好而成为气体分离膜基体材料的首选,但一般陶瓷基体表面粗糙并存在裂纹、针孔等缺陷,增加了气体分离膜的制备难度,并对分离膜的性能产生不利的影响。笔者采用溶胶—凝胶法对多孔陶瓷基体表面进行修饰,有效地降低了表面粗糙度,同时把基体渗透率调整到适宜值,以得到面向气体分离膜应用的多孔陶瓷基体。     

磷酸活化法制备半纤维素基颗粒活性炭

以半纤维素的主要模型物木聚糖为原料,在不添加其他粘结剂的条件下,采用磷酸活化法制备半纤维素基颗粒活性炭。讨论了浸渍比和炭活化工艺对活性炭吸附性能和孔隙结构的影响。研究结果表明:浸渍比的增加,有利于颗粒活性炭的比表面积、亚甲基蓝吸附值、强度、总孔容积和中孔容积的提高。随着炭活化温度的升高,颗粒活性炭的碘吸附值、亚甲基蓝吸附值、比表面积、总孔容积和微孔容积呈下降的趋势,强度呈上升趋势。N₂吸附-脱附等温线和孔径分析表明,颗粒活性炭具有发达的微孔结构,炭活化温度的升高不利于孔隙结构的发达。     

Super porous α-, β-, γ-cyclodextrin cryogels with high active agent loading and controllable release profiles

Cyclodextrins (CDs) are truncated cone-like structures that are natural cyclic oligosaccharides. Here, a simple preparation method for super porous poly(α-CD), poly(β-CD), and poly(γ-CD) cryogels crosslinking with divinyl sulfone at 150%, 100% and 125% mole ratios with respect to the α-CD, β-CD, and γ-CD molecules, respectively, under cryogenic conditions, is reported. The interconnected homogeneous pore distribution of CD-based cryogels with pore sizes in the range of 5–100 μm is confirmed by SEM analysis. The CD-based cryogels weighing 10 mg are determined as hemocompatible with <1% hemolysis ratios and >79% blood clotting indexes; whereas the same materials weighing 1 mg are biocompatible with >75% cell viability on L929 fibroblasts. Additionally, active agent adsorption/delivery efficiencies of CD-based cryogels utilizing two active agents, Bisphenol A (BPA, a carcinogenic compound) and Curcumin (CUR, a polyphenolic compound), are individually evaluated. It was revealed that p(γ-CD) cryogels exhibited the highest active agent loading capacity for BPA, 87 ± 13 mg/g, whereas p(α-CD) cryogels showed the highest loading capacity for CUR, 136 ± 4 mg/g. Moreover, the active agent release from p(α-CD), p(β-CD), and p(γ-CD) cryogel networks at pH 7.4 and 37°C were determined as 40.6 ± 2, 35.3 ± 2, and 34 ± 1 mg/g for BPA, and 1.07 ± 0.2, 1.27 ± 0.1, and 1.37 ± 0.1 mg/g for CUR, respectively, within 96 h.     

Microfluidic study of surfactant flooding of heavy oil in layered porous media containing fractures

Surfactant injection is a promising method for enhanced oil recovery (EOR) due to its effective micro-displacement mechanisms. However, understanding the interaction of a surfactant solution with heavy oil in porous media is neither straightforward nor well understood, particularly in heterogeneous systems. By enabling in-situ real-time monitoring of flow transport, microfluidic studies have provided novel insights into the underlying multiphase physics of flow at the pore scale. This paper examines the two-phase displacement efficiency of a new surfactant in layered–fractured porous microfluidic patterns, a topic seldom discussed in the literature. To evaluate the performance of the proposed surfactant, we considered several heterogeneous media with varying layer and fracture geometrical characteristics, quantifying displacement efficiency for each case. Based on the analysis of pore-scale snapshots, it was inferred that the primary mechanisms responsible for EOR during surfactant flooding into heavy oil include pore wall transportation, emulsifications, the deformation of residual oil, inter-pore or intra-pore bridging, and wettability alteration. Macroscopic displacement experiments revealed that the width of the swept area from surfactant injection significantly exceeded that of water injection, resulting in a substantially higher oil recovery. Furthermore, it was demonstrated that the direction of fluid flow in relation to fracture orientation plays a critical role in the dynamics of surfactant solution movement and, consequently, the ultimate oil production.     

钠硫电池β″-Al2O3陶瓷管几何参数对其机械强度的影响

为了有效增强陶瓷管的可靠性,达到大幅度提高钠硫电池使用寿命的目的,根据有限元理论,采用ANSYS软件对钠硫电池关键部件β″-Al2O3陶瓷管的机械强度进行了数值仿真,得出了陶瓷管最大应力随着其几何参数变化的规律。数值仿真结果表明：内外壁施压时陶瓷管最大应力随其长度与壁厚比的同比例缩小而增大,但随长度与直径比的同比例缩小而减小,而此时直径与壁厚比的同比例缩小对应力变化几乎没有影响,这为陶瓷管尺寸缩小时机械强度的优化设计提供指导。     

多孔超细旦涤纶预取向丝上油均匀性的工艺研究

研究了上油方式、油嘴型号、油剂特性、上油量、网络工艺对多孔超细旦涤纶预取向丝(POY)上油均匀性的影响。研究表明:依据品种规格选择合适的上油方式、油嘴型号,使用平滑性、乳液渗透性、耐高温性良好的油剂,调配成合适的油剂浓度,给不同规格纤维不同的上油量,同时采用网络喷嘴对丝条进行网络加工,生产的多孔超细旦涤纶POY上油均匀性优良,满足POY-DTY工艺要求。     

Y-TZP/Al_2O_3超细粉末的研究

用共沉淀法制备了3mol％Y_2O_3-ZrO_2-20Wt％Al_2O_3超细粉末。利用热分析、X射线、粒度分析仪、透射电镜和扫描电镜等研究了粉末的性能。实验结果表明:制备的粉末组分均匀,颗粒粒度为10nm,粒度分布窄,团聚体尺寸小,烧结活性高。粉末的相组成为t-ZrO_2。烧结体显微结构致密细晶,具有优异的力学性能。