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Based on the indentation fracture mechanics of brittle material, the correlations between the subsurface crack depth and the scratch depth induced by pyramidal, conical, and spherical indenters are established, respectively. Combined the kinematics of grinding process, the theoretical models of surface damage (SD) and subsurface damage (SSD) depths are developed considering the strain rate effect and the micro shape/geometry of abrasive grit. The mechanical properties of fused silica under different strain rates are measured by nanoindentation test. Many fused silica samples are processed under different grinding parameters, and their SD and SSD depths are measured. In combination with the experimental results, the theoretical models from differently shaped grits are assessed, and the effects of grinding/abrasive grit parameters are analyzed theoretically. The results show that compared with experimental SD and SSD depths, those calculated from spherical or pyramidal grit have average errors of less than 11.0% and 6.0%, respectively, while those from conical grit have average errors of more than 50.0% and 33.0%, respectively. The models from hybrid grit can be used to predict the SD and SSD depths efficiently, with average errors of 5.3% and 4.6%, respectively. The results also show that both SD and SSD depths increase with the grit apex angle, diameter, tip radius, or extraction depth. Moreover, the strain rate decreases with increasing grinding depth, feed speed, or grit diameter. The research is useful to optimize the grinding/abrasive grit parameters to reduce the damages in ground brittle materials.

For advanced fibrosis, isoprene is a typical characteristic marker that could be used to quickly screen the population for chronic liver disease (CLD). To achieve trace detection of isoprene, different mol% Pt-decorated In2O3 and pure In2O3 samples were prepared with the commonly used hydrothermal method. The obtained characterization results show that the prepared Pt-decorated In2O3 (1 mol%) sample had Pt nanoparticles uniformly attached to the surface of porous hierarchical In2O3 nanosheets, and the specific surface area was 62.3 m2/g. Subsequently, these sensors based on Pt–In2O3 and pure In2O3 nanomaterials were prepared, and their response characteristics were studied. The results show that the response of 1 mol% Pt–In2O3 to isoprene gas was significantly enhanced, and the optimal working temperature was 200 °C. The response of 1 mol% Pt–In2O3 to 5 ppb and 5 ppm isoprene was approximately 3.2 times and 25.9 times that of pure In2O3, respectively. Meanwhile, the 1 mol% Pt-modified sample exhibited excellent selectivity for isoprene relative to other biomarkers (carbon monoxide, hydrogen, ethanol, and ammonia). The sensor shows good repeatability and long-term stability. Therefore, the developed 1 mol% Pt-decorated In2O3 was expected to be applied as a gas-sensitive material for breath isoprene, which could be suitable for large-scale CLD rapid breath detection.

Recently, due to its advantages of inherent stability, non-toxicity, robustness, TiO2 has been used for the anode of lithium ion batteries (LIBs). Compared with TiO2, TiO has not only the above advantages of TiO2, but also a significantly better conductivity. However, on account of serious particle agglomeration, harsh and complex synthesis conditions, it is rarely reported as an electrode material. Hence, in this paper, we artfully develop an unique and facile synthetic route for the TiO/C hybrid nanotubes via the in-situ carbon reduction technology, where the TiO nanoparticles are embedded in carbon matrix. As the anode for LIBs, the hybrid porous TiO@C anode with a stable structure in the electrochemical reaction process, shows the high reversible capacity of 306 mA h g−1 at 0.2 A g−1 after 250 cycles, along with good rate capability and cycle performance. Meanwhile, the superior electrochemical properties of the electrode are attributed to the one-dimensional hybrid porous nanostructure that can prevent particle agglomeration and increase electrical conductivity.

Li 3 PO 4 -Li 2 SiO 3 thin films were prepared on the surface of Al 2 O 3 fine ceramic substrates by radio frequency (RF) magnetron sputtering. The thin films were treated at different annealing temperatures (400–800 °C) and for various time (0.5 h, 1 h,1.5 h, and 2 h) to investigate the influence of annealing conditions on the ionic conductive properties. The as-deposited and annealed thin films were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) to study the physical and structural features. Electrochemical impedance spectra (EIS) was carried out from 25 °C to 500 °C to analyze the temperature dependence of ionic conductivity. The results indicate that the crystalized Li 3 PO 4 -Li 2 SiO 3 thin films possess an enhanced ionic conductivity compared with crystallized single Li 3 PO 4 and Li 2 SiO 3 thin films. Moreover, the Li 3 PO 4 -Li 2 SiO 3 compound thin films exhibit a negative correlation between the ionic conductivity and annealing temperature, while the annealing time also showed similar passive effect on the conductivity. The Li 3 PO 4 -Li 2 SiO 3 compound thin films with enhanced ionic conductivity are suggested to exert good performance in lithium ion batteries and other lithium dominated conductors.

A new micro gas sensor based on the TiO 2 nanorod arrays (NRAs) was developed and its response properties to oxygen (O 2 ) at room temperature were investigated. The micro sensor combined a pair of micro interdigitated electrodes realized by the MEMS process and sensing materials based on the TiO 2 NRAs. The TiO 2 NRAs were selectively grown on the patterned straps of Ti/Pd films through the acid vapor oxidation (AVO) process. Relationship between the morphology of the TiO 2 NRAs and reaction temperatures was analyzed with the scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The results indicate that the diameters of the TiO 2 NRs enlarged as the reaction temperature increased from 140 °C to 180 °C. The TiO 2 NRAs sensors showed a good response to O 2 at room temperature (25 °C) due to the large specific surface areas of the TiO 2 NRs and the TiO 2 NR/NR junctions. The TiO 2 NRAs sensors prepared at 140 °C for 3 h exhibited better response properties to O 2 at room temperature with a fast response and recovery time. The research indicates that the TiO 2 NRAs prepared by the simple AVO process is a good choice for detecting O 2 at room temperature.