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This work describes a versatile electrospinning equipment with rapid, independent, and precise x–y–z movements for large-area depositions of electrospun fibers, direct writing or assembly of fibers into sub-millimeter and micron-sized patterns, and printing of 3D micro- and nanostructures. Its versatility is demonstrated thought the preparation of multilayered functional nanofibers for wound healing, nanofiber mesh for particle filtration, high-aspect ratio printed lines, and freestanding aligned nanofibers.

Although X-ray absorption spectroscopy (XAS) was conceived in the early 20th century, it took 60 years after the advent of synchrotrons for researchers to exploit its tremendous potential. Counterintuitively, researchers are now developing bench type polychromatic X-ray sources that are less brilliant to measure catalyst stability and work with toxic substances. XAS measures the absorption spectra of electrons that X-rays eject from the tightly bound core electrons to the continuum. The spectrum from 10 to 150 eV (kinetic energy of the photoelectrons) above the chemical potential—binding energy of core electrons—identifies oxidation state and band occupancy (X-ray absorption near edge structure, XANES), while higher energies in the spectrum relate to local atomic structure like coordination number and distance, Debye-Waller factor, and inner potential correction (extended X-ray absorption fine structure, EXAFS). Combining XAS with complementary spectroscopic techniques like Raman, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) elucidates the nature of the chemical bonds at the catalyst surface to better understand reaction mechanisms and intermediates. Because synchrotrons continue to be the light source of choice for most researchers, the number of articles Web of Science indexes per year has grown from 1000 in 1991 to 1700 in 2020. Material scientists and physical chemists publish an order of magnitude articles more than chemical engineers. Based on a bibliometric analysis, the research comprises five clusters centred around: electronic and optical properties, oxidation and hydrogenation catalysis, complementary analytical techniques like FTIR, nanoparticles and electrocatalysis, and iron, metals, and complexes.

Nanomaterials are commonly considered as those materials in which the shape and molecular composition at a nanometer scale can be controlled. Subsequently, they present extraordinary properties that are being useful for the development of new and improved applications in many fields, including medicine. In dentistry, several research efforts are being conducted, especially during the last decade, for the improvement of the properties of materials used in dentistry. The objective of the present article is to offer the audience a complete and comprehensive review of the main applications that have been developed in dentistry, by the use of these materials, during the last two decades. It was shown how these materials are improving the treatments in mainly all the important areas of dentistry, such as endodontics, periodontics, implants, tissue engineering and restorative dentistry. The scope of the present review is, subsequently, to revise the main applications regarding nano-shaped materials in dentistry, including nanorods, nanofibers, nanotubes, nanospheres/nanoparticles, and zeolites and other orders porous materials. The results of the bibliographic analysis show that the most explored nanomaterials in dentistry are graphene and carbon nanotubes, and their derivatives. A detailed analysis and a comparative study of their applications show that, although they are quite similar, graphene-based materials seem to be more promising for most of the applications of interest in dentistry. The bibliographic study also demonstrated the potential of zeolite-based materials, although the low number of studies on their applications shows that they have not been totally explored, as well as other porous nanomaterials that have found important applications in medicine, such as metal organic frameworks, have not been explored. Subsequently, it is expected that the research effort will concentrate on graphene and zeolite-based materials in the coming years. Thus, the present rev