Facile Preparation and Study of Self-healing Water-absorbing Expanding Elastomers.

The absorbent expansion elastomer plays a crucial role in engineering sealing and holds a promising future in this field as infrastructure continues to develop. Traditional materials have their limitations, especially when used in large construction projects where the integrity and reliability of the material are of utmost importance. In this work, a self-healing water-absorbing expansion elastomer was developed for continuous production at a large scale to monitor the sealing conditions of massive infrastructure projects. At room temperature, the material exhibited a repairing efficiency of 57.77% within 2 h, which increased to 84.02% after 12 h. This extended reaction time allowed for effective repairs when defects were detected. The material's strength reached approximately 3 MPa, making it suitable for a wide range of applications. The volume expansion rate of the material reached 200-400% for effective sealing, and the fictionalization of the packing made it have a good external force sensing effect and prevent heat build-up effect. The conductive detection performance of the absorbent expansion elastomer was improved by utilizing triple self-healing strategies, including dipole-dipole interaction, ion cross-linked network, and externally-aided restoration materials.

Photonic Integrated Circuit Based Temperature Sensor forOut-of-Autoclave Composite Parts Production Monitoring.

The use of composite materials has seen widespread adoption in modern aerospace industry. This has been facilitated due to their favourable mechanical characteristics, namely, low weight and high stiffness and strength. For broader implementation of those materials though, the out-of-autoclave production processes have to be optimized, to allow for higher reliability of the parts produced as well as cost reduction and improved production speed. This optimization can be achieved by monitoring and controlling resin filling and curing cycles. Photonic Integrated Circuits (PICs), and, in particular, Silicon Photonics, owing to their fast response, small size, ability to operate at higher temperatures, immunity to electromagnetic interference, and compatibility with CMOS fabrication techniques, can offer sensing solutions fulfilling the requirements for composite material production using carbon fibres. In this paper, we demonstrate a passive optical temperature sensor, based on a 220 nm height Silicon-on-Insulator platform, embedded in a composite tool used for producing RTM-6 composite parts of high quality (for use in the aerospace industry). The design methodology of the photonic circuit as well as the experimental results and comparison with the industry standard thermocouples during a thermal cycling of the tool are presented. The optical sensor exhibits high sensitivity (85 pm/°C), high linearity (R2 = 0.944), and is compatible with the RTM-6 production process, operating up to 180 °C.

RTM Production Monitoring of the A380 Hinge Arm Droop Nose Mechanism: A Multi-Sensor Approach.

This research presents a case study of production monitoring on an aerospace composite component: the hinge arm of the droop nose mechanism on the Airbus A380 wing leading edge. A sensor network composed of Fibre Bragg Gratings, capacitive sensors for cure monitoring and thermocouples was embedded in its fibre reinforced lay-up and measurements were acquired throughout its Resin Transfer Moulding production process. Two main challenges had to be overcome: first, the integration of the sensor lines in the existing Resin Transfer Moulding mould without modifying it; second, the demoulding of the component without damaging the sensor lines. The proposed embedding solution has proved successful. The wavelength shifts of the Fibre Bragg Gratings were observed from the initial production stages, over the resin injection, the complete curing of the resin and the cooling-down prior to demoulding. The sensors proved to be sensitive to detecting the resin flow front, vacuum and pressure increase into the mould and the temperature increase caused by the resin curing. Measurements were also acquired during the post-curing cycle. Residual strains during all steps of the process were derived from the sensors' wavelength shift, showing values up to 0.2% in compression. Moreover, the capacitive sensors were able to follow-up the curing degree during the production process. The sensors proved able to detect the resin flow front, whereas thermocouples could not measure an appreciable increase of temperature due to the fact that the resin had the same temperature as the mould.

Controle estatístico de processo univariado: monitoramento da produção de comprimidos de dipirona / Univariate Statistical Process Control: monitoring the production of dipyrone tablets

Investigou-se, através de histogramas e cartas de controle X e S, a ferramenta do Controle Estatístico de Processo (CEP) univariado e os parâmetros físicos dureza, peso médio e friabilidade da produção de dez lotes de dipirona sódica comprimidos. Por sua complexidade e influência no processo, a etapa de granulação de cada lote foi concomitantemente caracterizada através de determinações de densidade bruta, densidade compactada, índice de compressibilidade e fator de Hausner, além dos ângulos de repouso, tempos de escoamento e repartições granulométricas. As caracterizações dos granulados serviram como base na investigação da possível influência da etapa de granulação como uma das prováveis causas que poderiam levar o processo a se apresentar fora de controle estatístico. Os resultados da caracterização indicaram certa uniformidade entre os granulados, o que pode significar que não há ligação aparente entre a etapa de granulação e a falta de controle estatístico do processo, demonstrada na avaliação das cartas de controle. Na medida em que permitiu uma maior compreensão do processo, o CEP univariado mostrou sua importância no monitoramento da produção de comprimidos.

In this study, by means of histograms and and s control charts, the production control tool, univariate Statistical Process Control (SPC), was assessed for monitoring the physical variables hardness, weight and friability during the production of ten batches of sodium dipyrone tablets. In view of its complexity and influence on the process, the granulation step was concurrently characterized by determining the gross density, compacted density, compressibility index and Hausner factor, plus the angle of repose, flow time and particle size distributions of each batch. The properties of the granules were used as a basis for testing the hypothesis that the granulation step is probably the cause when the process runs out of statistical control. The results of the characterization indicated a degree of uniformity among the granules, which may mean that the lack of statistical process control demonstrated in the control charts does not arise from the granulation step. To the extent that it enabled a greater understanding of the process, univariate SCP proved its importance in the monitoring of tablet production.