Piezoelastic PVDF/TPU nanofibrous composite membrane: Fabrication and characterization

Poly (vinylidene fluoride) nanofibers (PVDF NFs) have been extensively used in energy harvesting applications due to their promising piezoresponse characteristics. However, the mechanical properties of the generated fibers are still lacking. Therefore, we are presenting in this work a promising improvement in the elasticity properties of PVDF nanofibrous membrane through thermoplastic polyurethane (TPU) additives. Morphological, physical, and mechanical analyses were performed for membranes developed from different blend ratios. Then, the impact of added weight ratio of TPU on the piezoelectric response of the formed nanofibrous composite membranes was studied. The piezoelectric characteristics were studied through impulse loading testing where the electric voltage had been detected under applied mass weights. Piezoelectric characteristics were investigated further through a pressure mode test the developed nanofibrous composite membranes were found to be mechanically deformed under applied electric potential. This work introduces promising high elastic piezoelectric materials that can be used in a wide variety of applications including energy harvesting, wearable electronics, self-cleaning filters, and motion/vibration sensors. - 2019 by the authors.The project was funded “partially” by Kuwait Foundation for the Advancement of Sciences under project code: PN17-35EE-02

Erratum: Piezoelastic PVDF/TPU nanofibrous composite membrane: Fabrication and characterization [Polymers, 11(10), 2019 (1634)] DOI: 10.3390/polym11101634

The authors wish to make a change to the published paper [1]. Regarding the author name Ahmed H. Hassanain, the last name Hassanain should be spelled Hassanin. The authors apologize for any inconvenience caused. The change does not affect the scientific results. The manuscript will be updated, and the original will remain online on the article webpage https://www.mdpi.com/2073-4360/11/9/1474. 2020 by the authors.Scopu

Multi-functional wet-electrospun piezoelectric nanofibers sensing mat: Manufacturing, characterization, and applications

This paper introduces the fabrication of multi-featured nanofibers membranes using wet-electrospinning process. Polyvinylidene fluoride (PVDF) nanofibers were wet-electrospun onto poly (3, 4-ethylenedioxythiophene) poly (styrene sulfonate) (PEDOT: PSS) coagulation bath to generate hybrid structure of piezoelectric multifunctional sensor. Therefore, the fabricated wet-electrospun nanofibers membrane shows piezo sensitivity up to 0.9 V/N and piezo coefficient (d33) of 27.2 pC/N. In addition, our fabricated membrane shows a variable surface roughness response up to 120 p.m. at an applied DC voltage of 10 V, as an opposite piezoelectric transducing mechanism. Also, our formed nanocomposite showed a strain sensing capability with conductivity variation of 0.01833 S/m per each 1% elongation strain. Furthermore, we have detected the effect of cyclic stretching strains over 100 times on the performance of both piezo response and strain sensing of our developed wetspun nanofibers. The presented work has a high potential to be applied in different applications related to wearable and flexible electronics as well as industrial mechanical transducers. 2023This work has not been funded by any research projects.Scopu

The role of point-of-care ultrasound (POCUS) imaging in clinical outcomes during cardiac arrest: a systematic review

Abstract Background Cardiac arrest in hospital and out-of-hospital settings is associated with high mortality rates. Therefore, a bedside test that can predict resuscitation outcomes of cardiac arrest patients is of great value. Point-of-care ultrasound (POCUS) has the potential to be used as an effective diagnostic and prognostic tool during cardiac arrest, particularly in observing the presence or absence of cardiac activity. However, it is highly susceptible to “self-fulfilling prophecy” and is associated with prolonged cardiopulmonary resuscitation (CPR), which negatively impacts the survival rates of cardiac arrest patients. As a result, the current systematic review was created to assess the role of POCUS in predicting the clinical outcomes associated with out-of-hospital and in-hospital cardiac arrests. Methods The search for scientific articles related to our study was done either through an electronic database search (i.e., PubMed, Medline, ScienceDirect, Embase, and Google Scholar) or manually going through the reference list of the relevant articles. A quality appraisal was also carried out with the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2), and the prognostic test performance (sensitivity and sensitivity) was tabulated. Results The search criteria yielded 3984 articles related to our topic, of which only 22 were eligible for inclusion. After reviewing the literature, we noticed a wide variation in the definition of cardiac activity, and the statistical heterogeneity was high; therefore, we could not carry out meta-analyses. The tabulated clinical outcomes based on initial cardiac rhythm and definitions of cardiac activity showed highly inconsistent results. Conclusion POCUS has the potential to provide valuable information on the management of cardiac arrest patients; however, it should not be used as the sole predictor for the termination of resuscitation efforts