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141.
Shear‐thinning hydrogels are useful for biomedical applications, from 3D bioprinting to injectable biomaterials. Although they have the appropriate properties for injection, it may be advantageous to decouple injectability from the controlled release of encapsulated therapeutics. Toward this, composites of hydrogels and encapsulated microgels are introduced with microgels that are fabricated via microfluidics. The microgel cross‐linker controls degradation and entrapped molecule release, and the concentration of microgels alters composite hydrogel rheological properties. For the treatment of myocardial infarction (MI), interleukin‐10 (IL‐10) is encapsulated in microgels and released from composites. In a rat model of MI, composites with IL‐10 reduce macrophage density after 1 week and improve scar thickness, ejection fraction, cardiac output, and the size of vascular structures after 4 weeks when compared to saline injection. Improvements are also observed with the composite without IL‐10 over saline, emphasizing the role of injectable hydrogels alone on tissue repair.  相似文献   
142.
Phosphorus-doped aluminium oxide thin films were deposited in a flow-type ALE reactor from AlCl3, H2O and from either P2O5 or trimethyl-phosphate. Structural information of the films was obtained from Fourier transform infrared (FTIR) spectra. Rutherford backscattering spectroscopy (RBS) was used to quantitatively determine the composition of the films. The P/Al intensity ratios calculated from X-ray fluorescence (XRF) results were in a linear relation with the P/Al concentration ratios calculated from RBS results. For comparison, the intensity ratios of the phosphorus peak (P=O) at about 1250 cm–1 and the aluminium peak (Al-O) at about 950 cm–1 were determined from the IR absorption spectra. The calibration of FTIR peak intensities was done by plotting the intensity ratios of phosphorus and aluminium peaks against the P/Al concentration ratios measured by RBS. FTIR gave also a linear calibration curve with RBS but the method is less suitable for routine analysis of P/Al ratio than XRF.  相似文献   
143.
A novel blue light emitting polymer was designed and synthesized via alternative conjugated 9,9-dioctylfluorene and 9-(6-(9H-carbazol-9-yl)hexyl)-9H-carbazole, named PF2Cz. It exhibited high thermal stability, good film morphology and strong deep-blue emission peaks at 408 and 429?nm in film. The triplet energy level of PF2Cz (ET?=?2.30?eV) was also improved. Non-doped and doped devices were both prepared by solution process to characterize the electroluminescent (EL) properties of PF2Cz. In non-doped devices, PF2Cz acted as blue emitter which exhibited a Commission Internation de L'Eclairage (CIE) coordinate of (0.164, 0.102) and a external quantum efficiency (EQE) values of 1.28%. Moreover, the doped phosphorescent devices utilized PF2Cz as host material obtained a closed-white light emission with a content of 1?wt% dopant. All these results indicated that the fluorene-carbazole derivatives could be a promising molecular design strategy for the synthesis of blue light and host organic semiconductors.  相似文献   
144.
Crosslinking is a feasible way to prepare biodegradable polymers with potential in biomedical applications such as controlled release of active agents and tissue engineering. A synthesis route in which functional telechelic aliphatic polyester oligomers are used as precursors for the preparation of crosslinked polyesters and poly(ester anhydride)s is described. Mechanical properties, degradation characteristics and rate, and bioactivity can be modified widely by controlling the chemical composition and architecture of the crosslinkable oligomers. In tissue engineering, photocrosslinking allows to use crosslinkable oligomers in advanced manufacturing techniques like micromolding in capillaries, stereolithography and two-photon polymerization.  相似文献   
145.
Dimethylamino‐(+)‐camphorenamine reacted with an equimolar amount of Piers’ borane, HB(C6F5)2, to give the corresponding iminium–hydroborate zwitterionic salt. Being in equilibrium with the parent enamine–HB(C6F5)2 N–B pair, this salt was able to split hydrogen heterolytically, hydrogenating the iminium group in the molecule. Detailed studies revealed that the hydrogen splitting in this reaction proceeded through an intermolecular pathway leading to a bornylamine–HB(C6F5)2 adduct. When the starting enamine is present in excess over HB(C6F5)2, the produced bornylamine–HB(C6F5)2 adduct breaks up, eliminating free bornylamine and forming the initial camphorenamine– HB(C6F5)2 pair. This results in hydrogenation of the camphorenamine framework in a catalytic fashion.  相似文献   
146.
Dissolved arsenic in drinking water is a global concern as it causes serious health problems. The purpose of this research was to study the applicability of an industrial intermediate product, a mixture of titanium hydroxide and titanium dioxide for removing aqueous arsenic. The material is common, inexpensive, and non-toxic, making it an attractive choice for drinking water purification. The kinetics and equilibrium of removing both primary inorganic arsenic forms, As(III) and As(V), were studied by separate batch experiments. The tested material functioned well in removing both of these arsenic forms. The apparent values for Langmuir monolayer sorption capacities were 31.8 mg/g for As(III) and 33.4 mg/g for As(V) at pH 4. The studied TiO(2) performed the best in acidic conditions, but also reasonably well in other pH conditions.  相似文献   
147.
镉配合物因其独特的结构及性质而被广泛应用于光学、医药、化学等领域,水热法因其溶剂清洁、操作简单等因素是目前合成配合物方便有效的方法之一.本文以2,6-双(2-吡嗪基)-4,4′-联吡啶(L)、对苯二甲酸和CdCl2·2.5H2O为原料,运用水热合成法合成了配位化合物[Cd2(L)2(bdc)(H2O)4](bdc),用...  相似文献   
148.
银/聚合物纳米复合材料   总被引:2,自引:0,他引:2  
银/聚合物纳米复合材料是一种典型的聚合物基复合材料, 其结构和性能依赖于合成方法,因此开发材料的优异性能必须以深入研究纳米材料的先进合成技术为前提。本文综述了纳米银粒子及其与聚合物形成的纳米复合材料的最新合成进展, 重点介绍了基于液相化学还原方法合成纳米银粒子的新方法, 如溶胶-凝胶法、沉淀法、微乳液法和离子液体法, 以及纳米银粒子的分散技术和原位法合成银/聚合物纳米复合材料的新技术, 并介绍了纳米银复合材料的电绝缘性、表面增强拉曼散射性能、抗菌性及其在生物医学等领域中的应用。  相似文献   
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