Room temperature aerobic oxidation of alcohols using CuBr 2 with TEMPO and a tetradentate polymer based pyridyl-imine ligand

ty10086 提交于 周四, 08/26/2021 - 13:42
Abstract(#br)A series of tetradentate pyridyl-imine terminated Schiff-base ligands has been investigated for their ability in the catalytic oxidation of alcohols when combined with copper bromide (CuBr 2 ) and 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO). Analogous bidentate ligands showed poorer catalytic activity and the ratio of Cu:ligand was of crucial importance in maintaining high yields.

A novel fabrication of a superhydrophobic surface with highly similar hierarchical structure of the lotus leaf on a copper sheet

ty10086 提交于 周四, 08/26/2021 - 13:36
Abstract(#br)A novel and facile avenue was developed to successfully fabricate a regular hierarchical surface structure on a copper sheet via the combination of polydimethylsiloxane (PDMS) template and chemical etching method in this paper. The as-prepared hierarchical surface structure was comprised of uniform-sized microprotrusions and nanostructures which was similar to the natural lotus leaf. After modified by stearic acid, the surface was covered with a layer of hydrophobic chemical groups and became superhydrophobic.

Rotating Disk Sorptive Extraction of Cu-Bisdiethyldithiocarbamate Complex from Water and Its Application to Solid Phase Spectrophotometric Quantification;Notes

ty10086 提交于 周四, 08/26/2021 - 12:59
This study demonstrates the first use of polydimethylsiloxane (PDMS) immobilized on a rotating disk for the extraction of copper from aqueous matrices and its subsequent direct determination by solid phase UV-Visible spectrophotometry. To accomplish the solid-phase extraction and the direct solvent-free spectrophotometric measurement, sodium diethyldithiocarbamate (NaDDTC) was used as an analytical reagent to form the uncharged chromophore complex Cu(DDTC)2, which absorbs at 432 nm.

材料在组织再生中促进血管生成的作用

ty10086 提交于 周三, 08/25/2021 - 16:55
促进血管生成对于组织修复治疗的成功和组织工程结构的命运至关重要。尽管许多生化信号分子已经被使用,但已知其在体内的生物学功能有限,主要是由于其寿命短,活性差。除了生化信号之外,基质(或工程生物材料)在刺激血管生成过程中起着关键作用。在这里,我们讨论了修复和再生各种组织,包括皮肤、骨、肌肉和神经所采取的促血管生成的努力,重点讨论了工程基质的作用。这包括孔结构和理化性质的设计(纳米拓扑、刚度、化学和可降解性)、基质的剪裁以恰当地呈现生长因子及其与黏附配体的串扰、血管生成分子和金属离子的控制和持续传递、细胞工程和预血管化组织的构建等。总体而言,材料驱动的策略是调整细胞和组织微环境,通过基质线索和适当呈现或传递信号分子和细胞,血管生成事件可以得到明显的青睐。

标签

细菌-和抗血清型超疏水聚氨酯海绵材料的制备。

ty10086 提交于 周三, 08/25/2021 - 16:41
表面生物膜和血栓形成在全球范围内造成了显著的发病率和死亡率,这突出了开发有效的防污染方法的重要性。本工作采用简单的两步浸涂法制备了具有优异的多液体斥力、杀菌性能和极低的细菌和血液附着力的新型高鲁棒性超疏水涂层。将1H、1H、2H、2H-全氟辛基三乙氧基硅烷( FAS-17 )包复的疏水性氧化锌和铜纳米粒子复合制备涂层,在商用聚氨酯( PU )海绵上构建分级微/纳米结构,然后进行聚二甲基硅氧烷( PDMS )处理,用于提高纳米粒子与海绵表面的结合程度。微/纳米织构的样品可以排斥各种液体,包括水、牛奶、咖啡、果汁和血液。与原PU相比,在连续滴流生物反应器中,制备的海绵超疏水特性使细菌(金黄色葡萄球菌)的粘附性在4天内显著降低,最高可达99.9 %。海绵对纤维蛋白原和活化血小板的粘附也有很强的抵抗力,分别降低76 %和64 %,从而降低凝血和血栓形成的风险。更为重要的是,海绵即使在受到不同类型的严酷机械损伤后,如手指划伤、刀划伤、胶带剥伤、手捏伤、手搓伤、弯曲伤、压缩释放( 1000个循环)试验,以及在250g装载量下1000cm砂纸擦伤,也能保持其超疏水性能。因此,该新型杂化表面具有较强的鲁棒性和抗血液粘附和细菌污染的能力,使其成为多种应用领域的理想选择。

重力推动过滤的功能化多孔过滤介质:综述了一种新的油水乳状液分离方法

ty10086 提交于 周三, 08/25/2021 - 16:41
油水分离技术在这些年来一直在不断进步。近来,重力辅助过滤得到了相当多的关注,尽管大部分研究集中在重力作用下容易分离的油水合成混合物。对于机械稳定和化学稳定的乳状液,除静态重力头外,不需要外加外部压力就可以分离是一个挑战。要实现这一目标,过滤介质应具有高孔隙率,以获得高通量,但要控制孔径,以获得高选择性。而且,为了分解乳液,过滤介质表面应赋予超润湿特性。本文综合评述了不同的多孔过滤介质(金属网、有机膜、无机膜、滤纸和三维材料)及其相应的改性技术和/或功能化策略,以改善其性能,实现高效重力驱动过滤应用。