The purpose of this study was to assess the influence of the types and thicknesses of glass ceramic plates on light transmittance and compare the degrees of conversion (DC) of resin cement under the ceramic materials. Three ceramic plates with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm were fabricated from each of five commercial ceramic blocks in shade A2: high-translucency and low-translucency IPS Empress CAD (Emp_HT and Emp_LT); high-translucency and low-translucency IPS e.max CAD (Emx_HT and Emx_LT); and Vita Mark II (Vita). The translucency parameter was obtained using a colorimeter. The light transmittance rate was measured using a photodetector attached to an optical power meter. The DC of a resin cement (Variolink N) underneath the ceramic plates was examined by Fourier transform infrared spectroscopy. The translucency parameter, light transmittance rate, and DC showed significant differences by ceramic type and thickness (P < 0.05). The Emp_HT specimens showed the highest light transmission and DCs, and the Emx_LT showed the least light transmission and the lowest DCs. The high-translucency Empress showed significantly higher DCs than the low-translucency types (P < 0.05), but there was no significant difference in e.max (P > 0.05). Both type and thickness of the glass ceramics significantly influenced the light transmittance and DC of the light-cured resin cement beneath the ceramic of the same shade.
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http://dx.doi.org/10.1038/s41368-017-0005-7 | DOI Listing |
ACS Mater Au
January 2025
Liquid Crystal Research Laboratory, Department of Physics, University of Lucknow, Lucknow, Uttar Pradesh 226007, India.
Polymer-dispersed liquid crystals (PDLCs) stand at the intersection of polymer science and liquid crystal technology, offering a unique blend of optical versatility and mechanical durability. These composite materials are composed of droplets of liquid crystals interspersed in a matrix of polymeric materials, harnessing the optical properties of liquid crystals while benefiting from the structural integrity of polymers. The responsiveness of LCs combined with the mechanical rigidity of polymers make polymer/LC composites-where the polymer network or matrix is used to stabilize and modify the LC phase-extremely important for scientists developing novel adaptive optical devices.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Key Laboratory of Cold Chain Logistics Technology for Agro-Product, Ministry of Agriculture and Rural Affairs/Institute of Agro-Product Processing and Nuclear Agricultural Technology, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; Hubei Engineering Research Center for Agro-Product Irradiation, Agro-product Processing Research Sub-center of Hubei Innovation Center of Agriculture Science and Technology, Wuhan 430064, China; Department of Materials Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing 210016, China. Electronic address:
The development of biomass material is an important approach to alleviating the excessive using of plastic packaging, by which the product could be more environmentally friendly and lower toxicity. In this study, we developed a biodegradable photodynamic antibacterial food packaging film using nitrogen-doped carbon quantum dots (N-CQDs) synthesized from crayfish shells, combined with konjac glucomannan (KGM) and sodium alginate (SA). Casting method was used to prepare the composite film and results indicated that incorporation of N-CQDs significantly enhanced the mechanical and barrier properties of the film by reducing the number of micropores.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
Harvard Medical School, Harvard University, Boston, MA, 02115, USA.
Ultra-broadband photodetectors (UB-PDs) are essential in medical applications, public safety monitoring, and various other fields. However, developing UB-PDs covering multiple bands from ultraviolet to medium infrared remains a challenge due to material limitations. Here, a mixed-dimensional heterojunction composed of 2D WS/monodisperse hexagonal stacking (MHS) 3D PdTe particles on 3D Si is proposed, capable of detecting light from 365 to 9600 nm.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Chemistry Institute, Universidad Nacional Autónoma de México, Circuito Exterior S/N, Ciudad Universitaria, Ciudad de México 04510, Mexico.
In this work, we present the green synthesis of complex - derived from β-hidroxymethylidene indanones by ultrasound, which allowed for the obtaining of compounds in a shorter time and with good yields. These organotin complexes were then doped with cobalt porphine and incorporated into a poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) matrix to manufacture composite semiconductor films. The semiconductor films were characterized through atomic force microscopy, examining their topography, Knoop hardness (around 17 HK), and tensile strength, which varied from 5 × 10 to 7 × 10 Pa.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
Center of Engineering, Federal University of Pelotas, Pelotas 96010-610, Brazil.
This study investigates the sustainable use of spp. bark through different chemical (hydrothermal, acid, alkaline, and bleaching) and physical (milling) pretreatments in the production of sustainable films. Valorization of agro-industrial residues and the demand for sustainable materials pose challenges for environmentally responsible solutions.
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