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Nanocrystalline CO₃O₄ particles were successfully synthesized by hydrothermal method under pulsed magnetic field. The effect of magnetic field and aging time on the morphology and microstructure were examined. Different morphologies were observed from SEM images for the samples fabricated with or without pulsed magnetic field. The pulsed magnetic field made CO₃O₄ sphere compact and more smooth surface. The hollow sphere morphology and refined grain of CO₃O₄ were formed after aging process.

Amorphous zirconium oxide (a-ZrO₂) thin films were prepared onto fuzzed quartz substrates by ion beam sputtering deposition (IBSD) method in (Ar +O₂) gas mixture. Optical parameters of the films were evaluated by laser ellipsometry (λ = 632.8 nm) and optical transmission measurements. Structural parameters were studied by XRD measurements. Variation of refractive index and film thickness have been defined as a function of time of high-temperature annealing at T = 900°C. Formation of monoclinic zirconium oxide (m-ZrO₂) nanocrystals with diameter of ~60 nm embedded into a-ZrO₂ matrix has been found by XRD analysis after long-time annealing.

A typical nitrogen doped spherical SiC nanocrystal with a diameter of 1.2 nm (Si₄₃C₄₄H₇₆) using linear combination atomic orbital (LCAO) in combination with pseudopotential density functional calculation have been studied. Our selected SiC nanocrystal has been modeled taking all the cubic bulk SiC atoms contained within a sphere of a given radius and terminating the surface dangling bonds with hydrogen atoms. We have examined nine possible situations in which nitrogen has a high probability for replacement in the lattice or placed between atoms in the nanocrystal. We have found that the silicone can substitute with a nitrogen atom in each layer as the constructed nanocrystals remain thermodynamically stable. Also the nitrogen atom can be placed between the free atomic spaces as the more thermodynamically stable position of the nitrogen is between the topmost layers. Also the optical absorption and refractive index energy dispersions of the pure and various stable doped SiC nanocrystals were studied.

A novel procedure to fabricate nanoarchitectures of crystalline titania hollow shells was developed by using assembled latex particles as templates. Latex particles were assembled on the surface of solid substrates and covered with ultrathin titania films by the surface sol–gel process. When the titania-covered latex particle was subjected to oxygen plasma treatment, hollow titania spheres were formed at the original site of particle deposition. Following calcination of the amorphous, titania hollow shells induced their crystallization to titania nanocrystals (anatase).

Monodispersed DAST nanocrystals have almost been successfully fabricated by means of the inverse reprecipitation method. By employing AC electric field, high electric field of above ca. 1.0 kVcm^-1 could be applied to polar DAST nanocrystals dispersed in decahydronaphthalene, so as to avoid electrophoresis of nanocrystals under DC electric field. The response of DAST nanocrystal dispersion to applied AC electric field was analyzed phenomenologically by fitting Langevin function, which provided a large permanent dipole moment of DAST nanocrystal. In addition, we have succeeded in in situ observation of AC electric-field-induced orientational motion of DAST crystals by using an optical microscope. The present DAST nanocrystal dispersion system will be expected as an optical device like display monitor.

Photoluminescent properties of CdSe/ZnS nanocrystals (quantum dots, QDs) in complexes with elongated gold nanoparticles was found to be dependent on the effective refractive index of the medium. It has been experimentally shown that changes in the refractive index make possible to increase the photoluminescence intensity by several times.

A series of cadmium telluride (CdTe) nanocrystals were synthesized by a modified organometallic synthesis method at various reaction temperatures ranging from 130 to 250°C. In this method, octadecylamine (ODA) was introduced as an additional coordinating component to the mixture of trioctylphosphine oxide (TOPO) and trioctylphosphine (TOP). CdO was used as a precursor. The prepared CdTe nanocrystals were studied by the absorption and emission spectra as well as the powder X-ray diffraction (XRD) patterns. The result shows that besides the traditional continuous-growth mode observed frequently at relatively high reaction temperature, a discontinuous-growth mode was confirmed at the initial growth stage of CdTe nanocrystals, arising from the change of the absorption spectra of CdTe nanocrystals with the reaction time at relatively low reaction temperature. The structures of CdTe nanocrystals, e.g., the cubic zinc blende structure at 160°C and the hexagonal wurtzite structure at 250°C, were characterized by XRD.

Colloidal CdSe nanocrystals (NCs) were etched after Se/TBP and Zinc stearate/ODE were injected into the mixture of as-prepared CdSe NCs and Copper (II) acetate in ODE solvent. Spectroscopic and structural investigations demonstrate the etching process. Along with the etching time, both the absorption and photoluminescence (PL) spectra of etched NCs showed blue-shift while the transmission electron microscopy (TEM) images indicated that the size of the NCs became from 5.6nm to 2.6nm. X-ray diffraction (XRD) patterns suggested that no other clusters or core/shell NCs were formed in the etching process and inductively coupled plasma (ICP) data demonstrated that only selenium and cadmium comprised the etched NCs. Electronic paramagnetic resonance (EPR) spectra indicated the deoxidization of Cu${}^{2+}$ ions and suggested the etching mechanism through cation exchange process.

The changing of materials surface properties method always was taken into improving the fatigue strength. In this paper, an ultrasonic nanocrystal surface modification(UNSM) technique was used on the SUS 304 stainless steel to form a nanostructured surface layer with different static load(70N, 90N, 110N, 130N) and the vibration strike number was about 20,000times/mm². The untreated and different condition specimens fatigue strength was all tested by a dual-spindle rotating bending fatigue test machine. SPring-8(a large synchrotron radiation facility) was used to test the surface nanocrystallization components. The X-ray diffraction (XRD), the scanning electron microscopy (SEM), optical microscope and a micro-Vickers hardness tester (MVK-E3, Akashi) were separately used to get the surface residual stresses, fracture surface after fatigue testing, metallographic structure and the microhardness of the nanostructured surface layer. The result showed that martensite transformation took place on the surface of specimens, the surface residual stresses had only a small increase and some cracks occurred between the martensite layer and the austenite layer, but the fatigue strength of 90N improved 81%.