A facile solvent-exchange strategy is devised to fabricate anti-drying, self-healing and transparent organohydrogels for stretchable humidity sensing applications.

Nanotherapeutics have been investigated for years, but only modest survival benefits were observed clinic. This is partially attributed to the short and rapid elimination of nanodrug after intravenous administration. In this study, a long circulation single wall carbon nanotube (SWCNT) complex was successfully fabricated through a new SWCNT dispersion agent, evans blue (EB). The complex was endowed with fluorescent imaging and photodynamic therapy ability by self-assembly loading an albumin coupled fluorescent photosensitizer, Chlorin e6 (Ce6) via the high affinity between EB and albumin. The yielding multifunctional albumin/Ce6 loaded EB/carbon nanotube-based delivery system, named ACEC, is capable of providing fluorescent and photoacoustic imaging of tumors for optimizing therapeutic time window. Synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) were carried out as guided by imaging results at 24 h post-injection and achieved an efficient tumor ablation effect. Compared to PDT or PTT alone, the combined phototherapy managed to damage tumor and diminish tumor without recurrence. Overall, our study presents a SWCNT based theranostic system with great promising in dual modalities imaging guided PTT/PDT combined treatment of tumor. The applications of EB on SWCNT functionalization can be easily extended to the other nanomaterials for improving their in vivo stability and circulation time.

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The effects of ultrasonic impact treatment (UIT) on the residual stress within a 45 mm-thick highstrength steel welded joint were investigated. The internal residual stresses after UIT was measured with contour method and compared with the as-welded stresses simulated by finite element method. The surface stresses were also measured by X-ray diffraction method and hole-drilling method to validate the simulation model. Results show that UIT introduces compressive stress layer in the weld zone and has the same effect on the longitudinal and transverse welding stresses; the interior stresses increase and demonstrate more uniform distribution after UIT; UIT would not affect the initial compressive stress presented far away from the weld zone.

A 3D thermal elastic-plastic finite element model to predict welding residual stresses induced by full-penetration laser welding of Ti6Al4V alloy was described in detail. The welding experiments and residual stresses measurements by through-thickness hole-drilling method were also performed to validate the simulated results. A uniform conical heat source model with parameters taken from the actual weld seam dimensions was developed to simulate the welding temperature fields with different welding heat inputs. The thermal elastic-plastic finite element simulation was employed to calculate the welding residual stresses. The boundary conditions and the size of finite element mesh were also discussed. The results show that the cross section profiles of the weld seam simulated with the conical heat source based on the configuration of weld seam agree well with the experimental results; the zone of residual stresses distribution in laser full-penetration welding of Ti6Al4V alloy is very narrow and the gradient of longitudinal residual stress is very steep; the residual stresses distribution on the surfaces are different from those in the interior of the welding seam; the measured residual stresses by through-thickness hole-drilling method are similar to the simulated ones in the interior of the welding seam.

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The stress distributions in a thick welded specimen with a partial repair weld were measured with the three-cut contour method. The longitudinal stress maps in the original weld and the repair weld were obtained and the transverse stress map at the weld centerline in the original weld was acquired. The difference between the longitudinal stress in the partial repair weld and that in the original weld was investigated. Results show that the longitudinal stress increases significantly within the entire repair region with a peak tensile longitudinal stress close to the yield strength of weld material; and the longitudinal stress in the region above the repair weld decreases distinctly after repair; the introduction of the partial repair weld does not affect the stress distribution trend in the original weld (whether it is beyond or above the repair weld), and it has a slight effect on the tensile stress distribution width in the repair region.