Abstract This study aimed to analyze the physical features and effect of hydroxyapatite (HAp) and Niobium/HAp CaNb2O6/Ca3(PO4)2 composite on critical size defect in rat calvaria. Biomaterials were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Particle size distribution (PSD) and Scanning Electron Microscopy (SEM). Critical size (8 mm) calvarial defects were created in Wistar rats (n = 24) distributed in three groups (90 days): Control group (CG): critical defect no treatment; HAp group: Hydroxyapatite; CNb/CPO group: CaNb2O6/Ca3(PO4)2 composite. After 90 days, calvaria samples were subjected to histological, and immunohistochemical reactions for osteopontin and osteocalcin, and Micro-CT analyses. XRD analysis confirmed the formation of a crystalline structure of CNb/CPO. XRF measurements confirmed the presence of Nb added in the sample CNb/CPO. Fracture toughness from CNb/CPO composite was 0.82 MPa.m1/2. Micro-CT showed increased trabecular number (p˂0.001), decreased porosities (%) (p˂0.001) and decreased trabecular separation (mm) (p˂0.001) in the CNb/CPO compared to CG group. In CNb/CPO group showed presence of new bone in which connective tissue differentiates to form or indicate a bone matrix score 3 (3-3.75, p˂0.05) and strong immunoexpression of osteopontin (p<0.05). The findings indicate that CNb/CPO showed resistance to the propagation of cracks and stimulated bone formation in calvaria defects in rats. (HAp NiobiumHAp Niobium CaNb2O6/Ca3PO42 CaNb2O6Ca3PO42 CaNbOCaPO CaNb2O6/Ca3 PO4 2 CaNb2O6 Ca3 CaNb O Ca PO CaNb2O6/Ca3(PO4) Xray X ray XRD, , (XRD) XRF, (XRF) PSD (PSD SEM. SEM . (SEM) 8 ( mm n 24 (9 days days) (CG) treatment Hydroxyapatite CNbCPO CNb CPO 9 histological osteocalcin MicroCT Micro CT analyses 082 0 82 0.8 MPam12 MPam MPa m1 m MPa.m1/2 p˂0.001, p0001 p p˂0.001 001 % (% (p˂0.001 (mm 33.75, 3375 3.75, 75 (3-3.75 p˂0.05 p005 05 p<0.05. p<0.05 (p<0.05) Ca3PO42 CaNb2O6/Ca3PO4 CaNb2O6Ca3PO4 CaNb2O6Ca3 CaNbOCa CaNb2O6/Ca CaNbO CaNb2O CaNb2O6/Ca3(PO4 (XRD (XRF (SEM (CG 08 0. MPam1 MPa.m1/ p000 p˂0.00 00 (p˂0.00 33 33.75 337 375 3.75 7 (3-3.7 p˂0.0 p00 p<0.0 (p<0.05 CaPO Ca3PO4 CaNb2O6/Ca3PO CaNb2O6Ca3PO CaNb2O6Ca CaNb2O6/Ca3(PO MPa.m1 (p˂0.0 33.7 37 3.7 (3-3. p˂0. p0 p<0. (p<0.0 Ca3PO MPa.m (p˂0. 33. 3. (3-3 p˂0 p<0 (p<0. (p˂0 (3- p˂ p< (p<0 (p˂ (3 (p< (p

Crystalline europium-doped indium hydroxide (In(OH)3:Eu) nanostructures were prepared by rapid and efficient Microwave-Assisted Hydrothermal (MAH) method. Nanostructures were obtained at low temperature. FE-SEM images confirm that these samples are composed of 3D nanostructures. XRD, optical diffuse reflectance and photoluminescence (PL) measurements were used to characterize the products. Emission spectra of europium-doped indium hydroxide (IH:xEu) samples under excitation (350.7 nm) presented broad band emission regarding the indium hydroxide (IH) matrix and 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 europium transitions at 582, 596, 618, 653 and 701 nm, respectively. Relative intensities of Eu3+ emissions increased as the concentration of this ion increased from 0, 1, 2, 4 and 8 mol %, of Eu3+, but the luminescence is drastically quenched for the IH matrix.

Rechargeable solid-state batteries have long been considered an attractive power source for a wide variety of applications, and in particular, lithium-ion batteries are emerging as the technology of choice for portable electronics. One of the main challenges in the design of these batteries is to ensure that the electrodes maintain their integrity over many discharge-recharge cycles. Fe3O4 deserves great attention as one of the most important electrode active materials due to its high theoretical capacity (926 mAhg- 1), low cost, being environmental-friendly and naturally abundance in worldwide. A simple strategy to synthesize magnetite nanoparticles (Fe3O4) by microwave-assisted hydrothermal method in a short processing time without further treatment is reported. The material obtained was tested as anode active material for lithium ions batteries. Impedance spectroscopy revealed that small differences in cell performance on cycling observed between samples cannot be strictly correlated to cell resistance. A high reversible capacity of 768.5 mAhg- 1 at 1C over 50 cycles was demonstrated, suggesting its prospective use as anode material for high power lithium ion batteries.