Improvement of lateral property of unidirectional-strengthened CFRP laminates using recycled carbon fiber.

The unidirectional carbon fiber reinforced polymer (UD-CFRP) lacks the modulus of elasticity and strength in the lateral direction. This study investigates whether matrix resin with CFRP waste, recycled carbon fiber (rCF), can improve the lateral properties of CFRP. In total, twelve CFRP strips specimen were prefabricated of unidirectional carbon fiber (CF) sheet by hand lay-up (HLU) method and were tested by tensile test and X-ray computed tomography (X-ray CT). Factors such as fiber direction and void distribution significantly affecting its mechanical properties are assessed by X-ray CT inspection. It can be seen that rCF is mixed in a random direction at the position filled with matrix resin without rCF. However, a similar frequency of unimpregnation and voids can be observed in both specimens. Test results showed that experimental values of CFRP laminates with rCF-mixed matrix resin increased compared to the CFRP laminates without rCF. The percentage increase in the lateral tensile strength and modulus of elasticity of the rCFRP compared to the control specimen without rCF is 27.36% and 10.62%, respectively. This study proved that rCF can increase the lateral properties of unidirectional CFRP and shows the effective use of rCF for strengthening material in construction applications.

Oxytocin levels and sex differences in autism spectrum disorder with severe intellectual disabilities.

There were few reports of oxytocin (OXT) concentrations of autism spectrum disorder (ASD) patients with severe intellectual disabilities. We measured serum OXT concentrations in 79 hospitalized patients with severe intellectual disabilities (16-60 years old, 50 males and 29 females, 54 ASD patients) and investigated the associations between serum OXT concentration, symptom scores, sex differences, and autism spectrum disorder. There were no significant effects of diagnosis, severity of intellectual disabilities, and total score of the Japanese version of the Aberrant Behavior Checklist (ABC-J), the Childhood Autism Rating Scale-Tokyo Version (CARS-TV), and the Japanese version of the Repetitive Behavior Scale-Revised (RBS-R). However, there were sex differences in the correlations between OXT concentrations and subscale scores in the ASD group. The male ASD group (n = 39) showed negative correlations between RBS-R Self-injurious and Sameness subscale scores and serum OXT concentrations. In the female ASD group(n = 15), CARS-TV Nonverbal communication subscale scores and RBS-R Compulsive subscale scores were seen to positively correlate with serum OXT concentrations. These findings suggest that OXT functions differ in males and females with severe intellectual disabilities and that OXT partly affects autism and related to some of the repetitive behaviors and nonverbal communication, in ASD patients with severe intellectual disabilities.

Extraordinarily large swelling energy of iodine-treated poly(vinyl alcohol) demonstrated by jump of a film.

Organic material characteristics of volume change and stress generation have attracted the attention of many researchers aiming to develop chemomechanical systems such as artificial muscles and polymer engines having the advantages of high energy density and silent operation. Although polymer gels offer a relatively large actuator stroke, their mechanical properties are relatively poor and the working temperature is relatively low, often limited by the evaporation of liquid if contained. We have developed an iodine-treated poly(vinyl alcohol) having extraordinarily large vapor-induced deswelling stress reaching 59 MPa, which is one to two orders of magnitude greater than those of ordinary polymer gels. Furthermore, this material has extremely large volumetric and gravimetric energy densities reaching 1.3 × 106 J m-3 and 9.6 × 102 J kg-1, respectively, and an elastic modulus of a few GPa and is heat-resistant to at least 200 °C. The high performance of this material can be demonstrated by a jump of a film. © 2014 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1357-1365.