Imaging feature-based clustering of financial time series.

Timeseries representation underpin our ability to understand and predict the change of natural system. Series are often predicated on our choice of highly redundant factors, and in fact, the system is driven by a much smaller set of latent intrinsic keys. It means that a better representation of data makes points in phase space clearly for researchers.

Ethanol-Quenching Introduced Oxygen Vacancies in Strontium Titanate Surface and the Enhanced Photocatalytic Activity.

Modification of the surface properties of SrTiO crystals by regulating the reaction environment in order to improve the photocatalytic activity has been widely studied. However, the development of a facile, effective, and universal method to improve the photocatalytic activity of these crystals remains an enormous challenge. We have developed a simple method to modify the surface environment of SrTiO by ethanol quenching, which results in enhanced UV, visible and infrared light absorption and photocatalytic performance.

Facile Strategy for Synthesizing Non-Stoichiometric Monoclinic Structured Tungsten Trioxide (WO) with Plasma Resonance Absorption and Enhanced Photocatalytic Activity.

Oxygen vacancy defects play an important role in improving the light-capturing and photocatalytic activity of tungsten trioxide (WO₃). However, the hydrogen treatment method that is commonly used to introduce oxygen vacancies is expensive and dangerous. Therefore, the introduction and control of oxygen vacancy defects in WO₃ remains a challenge.

A Facile Approach to Prepare Black TiO₂ with Oxygen Vacancy for Enhancing Photocatalytic Activity.

Black TiO₂ has triggered worldwide research interest due to its excellent photocatalytic properties. However, the understanding of its structure–property relationships and a more effective, facile and versatile method to produce it remain great challenges. We have developed a facile approach to synthesize black TiO₂ nanoparticles with significantly improved light absorption in the visible and infrared regions.

Effect of Gallium and Indium Co-Substituting on Upconversion Properties of Er/Yb:Yttrium Aluminum Garnet Powders Prepared by the Co-Precipitation Method.

Gallium and Indium co-substituted Yb, Er:YAG was fabricated through the chemical co-precipitation method. The formation process and structure of the Ga3+ and In3+ substituted phosphor powders were characterized by the X-ray diffraction, thermo-gravimetry analyzer, infrared spectra, and X-ray photoelectron spectroscopy, and the effects of Ga3+ and In3+ concentration on the luminescence properties were investigated by spectrum. The results showed that the blue shift occurred after the substitution of Ga3+ and In3+ for Al3+ in matrix, and the intensity of emission spectrum was affected by the concentration of Ga3+ and In3+.

[Structure and luminescence properties of Ga2O3 : Cr3+ by Al doping].

The Al doping gallate phosphor (Ga(1-x)Al(x))2O3 : Cr3+ (x = 0, 0.1, 0.2, 0.

[Luminescence properties of Eu, Dy doped BaAl12 O19 long afterglow phosphors].

Long afterglow phosphors BaAl12 O19:Eu2+/Eu3+, Dy3+ were synthesized by high temperature solid state method under different atmosphere. X-ray powder diffraction (XRD) shows that pure BaAl12 O19 phase structure was obtained and the do ping ions Eu2+/Eu3+, Dy3+ didn't change the phase structure. By comparison, the authors found that the doping ions Eu2+/ Eu3+, Dy3+ caused the XRD diffraction peaks moving to the high angle slightly which displayed that the inter-planar spacing was changed via Eu and Dy replacing Ba lattice in BaAl12 O19.

(1+1) Resonance-enhanced multiphoton ionization and photodissociation study of CS2 via the 1B2 state.

(1+1) Resonance-enhanced multiphoton ionization (REMPI) spectra of CS(2) and molecular dissociation dynamics are investigated using a time-of-flight mass spectrometer equipped with velocity imaging detection. The REMPI spectra via a linear-bent 1Sigma(g)+-->(1)B(2)(1Sigma(u)+) transition are acquired in the wavelength range of 208-217 nm. Each ro-vibrational band profile of the (1)B(2)(1Sigma(u)+) state is deconvoluted to yield the corresponding predissociative lifetime from 0.

Normal Auger spectra of Br in alkali bromide molecules.

Molecular Auger electron spectra following the bromine 3d ionization in gas-phase alkali bromides and in HBr were studied both experimentally and theoretically. The AES for HBr and CsBr were measured using photoexcitation, and for LiBr, NaBr, and KBr by using electron impact. These results are compared with the theoretical spectra from nonrelativistic ab initio calculations and one-center approximation and with the spectra of Br(-), computed with the multiconfiguration Dirac-Fock method.