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A novel diamine named (2,2′-bibenzoxazole)-5,5′-diamine (DBOA) and derived polyimides (PIs) were successfully synthesized. The rigid, linear, symmetrical molecular structure and the strong charge transfer complex (CTC) were considered to be the reasons for the improved molecular packing and enhanced thermal properties of the polymers. These DBOA based PIs exhibited a higher glass transition temperature (Tg) and lower coefficient of thermal expansion (CTE) than traditional benzoxazole (BOA) based PIs. Meanwhile, the PI derived from DBOA and BPDA (3,3′,4,4′-biphenyltetracarboxylic dianhydride) exhibited high Tg (395 °C) and low CTE (8.9 ppm per °C), and is expected to be applied in organic light-emitting diode (OLED) displays.

Nanosized titanium oxide (TiO2)-based photocatalysts have exhibited great potential for the degradation of organic contaminants, while their weak absorption of visible light limits the photocatalytic efficiency. Herein, a novel reduced graphene oxide/TiO2-polyphenylenesulfone (rGO/TiO2-PPSU) hybrid ultrafiltration membrane has been successfully prepared via a non-solvent induced phase-separation method, in which the synergistic coupling between the rGO and TiO2 could endowed the fabricated membranes with visible-light-driven efficient photocatalytically degradation of organic pollutants and outstanding photocatalytic and antifouling properties. Compared with the PPSU membranes prepared with Graphene oxide and TiO2, respectively, the rGO/TiO2-PPSU membrane demonstrated significant photodegradation towards phenazopyridine hydrochloride (PhP) solution under ultraviolet light (improved about 71 and 43%) and visible light (improved about 153 and 103%). The permeability and flux recovery rates of the membrane indicated that the high flux of the rGO/TiO2-PPSU membrane can be greatly restored after fouling, due to the improved self-cleaning properties under visible light static irradiation. With the properties of high performance of photocatalytic degradation and good self-cleaning ability, the rGO/TiO2-PPSU membrane would have great potential in water treatment.

Mestrado Bolonha em Desenvolvimento e Cooperação Internacional O rápido desenvolvimento económico da China a partir da década de 1980 trouxe a prosperidade política e cultural através de política de reforma e abertura, mas também trouxe o crescimento da corrupção no Partido Comunista Chinês. O governo chinês iniciou uma série de investigação de corrupção desde o 18º Congresso Nacional do Partido Comunista Chinês em 2012 e tentou aplicar a tecnologia da informação ao trabalho anticorrupção. Propõe-se a observar a atualidade da campanha anticorrupção por meio de tecnologia da informação, segundo as políticas atuais, analisando as insuficiências dessa forma na luta contra corrupção. As observações mostram-nos a falta de regulações formais e a falta de proteção de privacidade pessoal são obstáculos para a promoção de campanha anticorrupção através de tecnologia de informação. Por meio de estudo de legislação pertinente e de tecnologia de blockchain com metodologia qualitativa, procede-se a comparação e a combinação entre a tecnologia de blockchain e aplicação de tecnologia de informação na campanha anticorrupção. O estudo descobriu a semelhança entre as duas tecnologias e a possibilidade de aplicação de tecnologia de blockchain na campanha anticorrupção chinesa para resolver o problema de segurança dos dados, privacidade pessoal e legislações. Concluiu que a tecnologia de blockchain é aplicável para a campanha anticorrupção chinesa e que para tal, é necessário também, o governo possui uma legislação e regulação forte, de modo que as tecnologias novas podem promover o desenvolvimento do sistema governamental. China's rapid economic development since the 1980s has brought political and cultural prosperity through policy reform and opening up, but it has also brought the growth of corruption in the Chinese Communist Party. The Chinese government has launched a series of corruption investigations since the 18th National Congress of the Chinese Communist Party in 2012 and has tried to apply information technology to anticorruption campaign. This dissertation proposes to observe the actuality of the anticorruption campaign through information technology, according to current policies, analyzing the insufficiencies in this way in the fight against corruption. The observations show us that the lack of formal regulations and the lack of protection of personal privacy are obstacles to promoting an anti-corruption campaign through information technology. Through a study of relevant legislation and blockchain technology with a qualitative methodology, a comparison and combination between blockchain technology and the application of information technology in the anti-corruption campaign is carried out. The study found the similarity between the two technologies and the possibility of applying blockchain technology in the Chinese anti-corruption campaign to solve the problem of data security, personal privacy and legislation. The dissertation concluded that blockchain technology is applicable to the Chinese anti-corruption campaign and that for this, it is also necessary, the government has strong legislation and regulation, so that new technologies can promote the development of the government system. info:eu-repo/semantics/publishedVersion

Chopped polyimide (PI) fiber-reinforced polyether ether ketone (PEEK) composites with different fiber content (0%, 10%, 20%, and 30%) were prepared via melt extrusion using a twin-screw extruder. The impact strength of these composites significantly improved from 4.9 kJ m−2 to 9.3 kJ m−2 with the increase of the PI fiber content from 0% to 30%. Tensile strength, tensile modulus, and flexural strength also increased with the increase in PI fiber content. In addition, the heat deflection temperature increased significantly from 160°C to 318°C. The results of the dynamic mechanical analysis revealed that the storage modulus increased considerably. The relationship between mold temperature and composite properties was investigated, and using differential scanning calorimetry, it was shown that the increase in mold temperature improved the degree of polymer crystallization and the bonding capability of the fiber and resin interface. As a result, the mechanical properties of the composite material were improved.

Zwitterionic nano-silica (SiO2 NPs) obtained by lysine surface modification was used as a hydrophilic inorganic filler for preparing a poly(aryl ether nitrile) (PEN) nanocomposite membrane via an immersion precipitation phase inversion method. The effects of zwitterionic SiO2 NPs addition on the morphology, separation and antifouling performance of the synthesized membranes were investigated. Zwitterionic surface modification effectively avoided the agglomeration of SiO2 NPs. The PEN/zwitterionic SiO2 NPs composite membranes exhibited improved porosity, equilibrium water content, hydrophilicity and permeability due to the introduction of hydrophilic SiO2 NPs in the casting solution, and the optimal pure water flux was up to 507.2 L m−2 h−1, while the BSA rejection ratio was maintained at 97.4%. A static adsorption capacity of 72.9 μg cm−2 and the FRR up to 85.3% in the dynamic antifouling experiment proved that the introduction of zwitterionic SiO2 NPs inhibited irreversible fouling and enhanced the antifouling ability of the PEN membrane.