The present study investigates the origin of voids in sheet molding compounds (SMCs) sheets and their transport during the manufacturing steps. Paste mixing, impregnation, thickening, and molding have been performed with five different SMC sheets, one without fibers and the others with four different types of glass fiber bundles. The fiber surface energy and bending rigidity were quantified, together with the paste surface energy. Void content was then measured at each manufacturing step. Two main void origins in SMC sheets have been observed: (i) air entrapment during paste mixing and (ii) poor bundle impregnation. These voids may be largely removed during SMC manufacturing. The quality of impregnation and void elimination during the flow is found to depend on the bundle characteristics (rigidity and surface energy) conferred by their sizing and over sizing. POLYM. COMPOS. 27:289–298, 2006. © 2006 Society of Plastics Engineers

No abstract

No abstract

Background Sustainability of hand hygiene is challenging in low resource settings. Adding ownership and goal setting to the WHO-5 multimodal intervention may help sustain high compliance. Aim To increase and sustain compliance of nursing and medical staff with hand hygiene in a tertiary referral center with limited resources. Methods A quality improvement initiative was conducted over two years (2016–2018). After determining baseline compliance rates, the WHO-5 multimodal intervention was implemented with staff education and training, system change, hospital reminders, direct observation and feedback, and hospital safety climate. Additionally, the medical staff was responsible for continuous surveillance of compliance ( ownership ) until rates above 90% were achieved and sustained ( goal setting) . Results Of 2987 observations collected between August 2016 and April 2018, 1630 (54.5%) were before, and 1357 (45.5%) were after patient encounters. The average overall compliance with hand hygiene was sustained at 94% for nursing and medical staff. Two instances of drops below 90% were associated with incidence of nosocomial Rotavirus infections. There were no similar infections during intervention periods with compliance rates above the set goal. Analysis using p-charts revealed significant improvement in compliance rates from baseline (χ 2 (1) = 7.94, p = 0.005). Conclusion Adding ownership and goal setting to the WHO-5 multimodal intervention may help achieve, and sustain high rates of compliance with hand hygiene. Involving health care workers in quality improvement initiatives is feasible, durable, reliable, and cheap, especially in settings with limited financial resources.

The correlation between sizing formulation, bundle mechanical characteristics, and bundle-matrix static and dynamic interactions are investigated. Two glass-fiber sizing formulations are considered, one containing polyvinyl acetate (PVAc) and the other polyester/PVAc, as conventionally used in sheet molding compounds (SMC). Axial compression tests are conducted on dry two-dimensional (2D) random suspensions. The forced packing is governed by the bending of fiber bundle segments between bundle-bundle contact points. Benchmarking of the experimental curves with a modified theoretical model provides an estimation of the fiber bundle bending rigidity under forced packing conditions. This value is found to depend on the bundle sizing as well as on the interaction with solvents present in the matrix as is the case for SMC. Free flow and molding experiments are performed on planar SMC sheets using the two different fiber bundles as reinforcements. The results confirm the dependence of the molding energy and the SMC rheology on the bundles chemical and mechanical characteristics. POLYM. COMPOS., 26:370 -376, 2005.