Exploring the charge transfer enhancement mechanism in selective SERS detection with MoWS@AgS nanosheets.

In order to solve the problem of poor sensitivity and selectivity of conventional SERS substrates, we synthesized MoWS@AgS nanosheets in this paper by a two-step hydrothermal method. The structure and morphology of the synthesized MoWS@AgS nanosheets were characterized by XRD and SEM,respectively. The results show that the MoWS@AgS nanosheet has an irregular layered structure.

A balsam pear-shaped CuO SERS substrate with highly chemical enhancement for pesticide residue detection.

Simple and traditional hydrothermal fabrication of a novel balsam pear-shaped CuO with high SERS enhancement is presented. XRD (X-ray diffraction), SEM (scanning electronic microscopy), TEM (transmission electron microscope), HRTEM (high-resolution transmission electron microscope), UV-Vis, and Raman are adopted to ensure that this balsam pear-shaped CuO with dense nanoparticle protuberance is successfully prepared. The LOD of this CuO SERS substrate is 4.

A facile seed growth method to prepare stable Ag@ZrO core-shell SERS substrate with high stability in extreme environments.

A stable substrate is extraordinarily important for the trace detection of Surface Enhanced Raman Scattering technique. We have designed in this paper a simple seed growth method to prepare Ag@ZrO core-shell nanoparticles as well as regulate the core-shell ratio by adjusted concentration of zirconium propoxides added. The shell thickness effect and spacing on SERS activities have been simulated in different finite time domains, which goes perfectly with those previous experiment results.

Facile Reduction Method Synthesis of Defective MoO Nanospheres Used for SERS Detection with High Chemical Enhancement.

Recently, more and more attention has been given to a semiconductor oxide-based surface-enhanced Raman spectroscopy substrate for its great stability and biocompatibility. However, its poor SERS sensitivity limits the applications of semiconductor oxide SERS substrates. In this paper, we provide a facile reduction method to modulate oxygen vacancy concentrations in oxide SERS substrates.

SERS based determination of vanillin and its methyl and ethyl derivatives using flower-like silver nanoparticles on a silicon wafer.

A surface enhanced Raman scattering (SERS) method is described for the determination of vanillin, methyl vanillin and ethyl vanillin at trace levels. Flower-like silver nanoparticles on a silicon wafer are used as the SERS substrate, and the analytes can be specifically and non-destructively recognized by their specific Raman bands. The molecules can be recognized rapidly by identifying the characteristic bands.

Rapid qualitative and quantitative determination of food colorants by both Raman spectra and Surface-enhanced Raman Scattering (SERS).

Surface Enhanced Raman Scattering (SERS) spectroscopy technology is widely used in materials analysis, environmental monitoring, biomedical, food security and other fields. Flower-shaped silver nanoparticles have been successfully synthesized by a simple aqueous phase silver nitrate reduction by ascorbic acid in the presence of polyvinylpyrrolidone (PVP) surfactant. The nanoparticles diameters were adjusted from 450 to 1000nm with surface protrusions up to 10-25nm.

Design of a silver nanoparticle for sensitive surface enhanced Raman spectroscopy detection of carmine dye.

Flower-shaped silver nanoparticles have been successfully synthesized by a simple aqueous phase silver nitrate reduction by ascorbic acid in the presence of polyvinylpyrrolidone (PVP) surfactant. The nanoparticles diameters were adjusted from 450 to 1000nm with surface protrusions up to 10-25nm. The growth direction of silver nuclei is controlled by their degree of coating by PVP.

[Quantitative Analysis of Mg, Fe and Ca in Jade with Laser Induced Breakdown Spectroscopy].

Based on laser induced breakdown spectroscopy and X-ray fluorescence spectroscopy, The calibration curve of the main elements Mg, Cr and trace element Fe in the Jade samples is obtained based on experimental results. In the experiment, LIBS experiment conditions were 3 μs delay, 110 accumulated laser pulse, 100 mJ·pulse-1, 10 Hz pulse repetition frequency, plasma in Nanyang jade was induced using nono-second Nd∶YAG (wavelength: 1 064 nm) laser as the excitation source in the atmosphere envtronment of the laboratory. The spectral lines in the 300~1 000 nm wavelength range have been identified with the laser-induced breakdown spectroscopy.

Preparation and SERS Study of Silver Microstructures with Dendritic Shape.

In the surface ehanced Raman scattering (SERS) technology, not only to improve the making process of SERS substrates, to be fast and easily, but also to enhance the SERS enhance factor, an easy replacement reaction between zinc and silver nitrate solution has been adopted to prepare silver micro-structures SERS-active substrate. The silver micro-substrates have many advantages. These substrates have good stability, well preservation, an easy making method and a fast making process.

[Photoelectric parametric test system of LED based on virtual instrument].

The standardized measuring principle, requirements and implementations of the above parameters of LEDs were researched and analyzed in the present paper. Then a comprehensive test system involved with optics, machinery and computer was designed to accomplish data acquisition, algorithm design and interface design on virtual instrument using NI data acquisition card USB6210. And convincing results of LEDs' parameters, including peak wavelength, width of half-peak wavelength, centroid wavelength, chromaticity coordinates, purity, correlated color temperature and the forward voltage/current, were achieved with good consistency based on the measured spectrum.

[Progress in the research on silicon-nitrogen based phosphor for white LED].

With the rapid development of white LED technology, the traditional YAG : Ce3+ phosphor is difficult to meet the requirement due to the low color rendering and high color temperature. Using ultraviolet chip to stimulate the tri-phosphor has become an effective way for white LED, and it is urgent to develop novel tri-phosphor with high-performance, especially for red light-emitting materials. Silicon-nitrogen based compounds contain the network structure composed of SiN4 tetrahedron, with higher chemical and thermal stability.

[Study on Sr3LiMgV3O12 : Eu3+ single-phase phosphor for white LED].

A novel broadband emission phosphor Sr(3-2x) Li(1+ x) MgV3 O12 : xEu3+ was synthesized by a solid-state reaction method. Then discussed the luminous property under the influence of temperature and doping density of Eu3+, was discussed. X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence spectra were used to characterize the feature of Sr(3-2x)Li(1+x)MgV3O12 : xEu3+.

Enhancement of the accuracy of the simplified modal method for designing a subwavelength triangular grooves grating.

The validity and accuracy of the simplified modal method for a highly efficient transmission subwavelength triangular grating are fully and quantitatively evaluated by a comparison of diffraction efficiencies predicted from the modal method to exact results calculated by a rigorous coupled wave analysis. The larger errors are revealed in smaller periods and in lower groove depths. More importantly, with the consideration of the reflection loss of the two propagating modes, the accuracy of the simplified modal method is significantly enhanced.

Effect of dopant composition ratio on nonvolatile holographic recording in LiNbO3:Cu:Ce crystals.

The effect of dopant composition ratio on nonvolatile holographic recording in LiNbO3:Cu:Ce crystals is investigated experimentally. The results show that the dopant composition ratio affects the recording sensitivity and fixed diffraction efficiency by altering the UV light absorption characteristics of the crystals during nonvolatile, holographic recording. Increasing the dopant composition ratio of Cu and Ce leads to an increase in the absorption of UV light and further to an increase in the recording sensitivity and fixed diffraction efficiency.