Optical characteristics of bilayer decoupling MoS grown by the CVD method.

Study of exciton recombination process is of great significance for the optoelectronic device applications of two-dimensional transition metal chalcogenides (TMDCs). This research investigated the decoupling MoS structures by photoluminescence (PL) measurements. First, PL intensity of the bilayer MoS (BLM) is about twice of that of the single layer MoS (SLM) at low temperature, indicating no transition from direct bandgap to indirect bandgap for BLM due to the decrease of interlayer coupling which can be shown by Raman spectra.

Aromatic Thioacetal-Bridged ROS-Responsive Nanoparticles as Novel Gene Delivery Vehicles.

In this report, a series of polycations are designed and synthesized by conjugating reactive oxygen species (ROS)-responsive thioacetal-linkers to low molecular weight (LMW) polyethylenimine (PEI) via ring-opening polymerization. Their structure⁻activity relationships (SARs) as gene delivery vectors are systematically studied. Although the MWs of the target polymers are only ~9 KDa, they show good DNA binding ability.

[Spectrum diagnostics for the time of pre-sputtering in thin films deposited by magnetron puttering].

Abstract A plasma analysis system comprised of Omni-X300 series grating spectrometer, CCD data acquisition system and optical fiber transmission system was utilized in the present paper to realize the real-time acquisition of plasma emission spectra during the process of radio frequency (RF) magnetron sputtering. The plasma emission spectra produced by NiTa, TiAl ceramic targets and NiA1, TiA1 alloy targets were monitored respectively, in addition, the behavior of analysis lines of Ta I 333.991 nm, Ni I 362.

[Spectrum diagnostics for optimization of experimental parameters in thin films deposited by magnetron sputtering].

The plasma emission spectra generated during the deposition process of Si-based thin films by radio frequency (RF) magnetron sputtering using Cu and Al targets in an argon atmosphere were acquired by the plasma analysis system, which consists of a magnetron sputtering apparatus, an Omni-lambda300 series grating spectrometer, a CCD data acquisition system and an optical fiber transmission system. The variation in Cu and Al plasma emission spectra intensity depending on sputtering conditions, such as sputtering time, sputtering power, the target-to-substrate distance and deposition pressure, was studied by using the analysis lines Cu I 324. 754 nm, Cu I 327.

[Effect of KCI additive on laser-induced soil plasma radiation].

In order to improve laser-induced breakdown spectroscopy for low-level elements testing capability, the enhancement effects of KCl additive on the emission spectra of soil samples were studied. The laser spectrum analytical system is composed of a high-energy neodymium glass laser ablating samples, a multifunctional and automatic scanning spectrometer, and a CCD data acquisition system recording plasma spectra. The electron temperature and electron density of plasmas were calculated by measuring spectral line intensity and stark broadening respectively.

[Spectral characteristics of Ba2B2P2O10 : Eu3+ phosphor].

Ba2B2P2O10 : Eu3+ phosphor was synthesized by high temperature solid-state method. BaCO3(A.R), NH4H2PO4 (A.

[Spectral properties and energy transfer of Ce3+ and Tb3+ ions co-doped Ca2SrAl2O6 phosphor].

Ce3+, Tb3+ co-doped green phosphor Ca2SrAl2O6 was synthesized by solid state method and its excitation and emission spectra were measured and studied. The results showed that the emission spectrum is composed of four groups of narrow bands and the peaks are located at 497, 545, 595 and 623 nm. The strongest emission peak islocated at 545 nm and chromaticity coordinate (x, y) is (0.

[Enhancing effect of sample additive on laser-induced plasma radiation].

In order to improve the radiation characteristic of laser-induced plasma, with the national standard soil taken as the target sample, a laser spectrum analytical system which composed of a high-energy neodymium glass laser, a multifunctional and compact integrated spectrometer, and a CCD detector was used to detect the influence of the NaCl sample additive on the laser plasma radiation intensity. The electron temperature and the electron density of the plasmas were also calculated from the lines intensity and stark broadening of emission spectral line respectively. The experimental results indicated that with the increase in the NaCl additive, the spectral intensity, signal-to-background ratio, the electron temperature, and the electron density all went up firstly and then down.

[Spectral characteristics of Ce3+ in alkali-alkaline earth borate system].

Alkali-alkaline earth borate LiCaBO3 : Ce3+, LiSrBO3 : Ce3+ and LiBaBO3 : Ce3+ were investigated by solid-state method. CaCO3 (99.9%), SrCO3 (99.

[Study of spectra characteristics of Dy3+ -activated LiSrBO3 phosphor].

The LiSrBO3:Dy3+ phosphor was synthesized by solid-state method. SrCO2 (99.9%), Li2CO3 (99.

[Spectra characteristics of LiM (M = Ca, Sr, Ba) BO3 : Tb3+ phosphor].

LiM (M = Ca, Sr, Ba) BO3 : Tb3+ phosphors were synthesized by solid state reaction. The starting materials CaCO3, SrCO3, BaCO3, H3 BO3, Li2 CO3, Na2 CO3, K2 CO3 and Tb4 O7 (99.99% in mass) in appropriate stoichiometric ratio were mixed in the alumina crucible, then the mixed powders were calcined at 700 degrees C for 2 h, and LiCaBO3 : Tb3+, LiSrBO3 : Tb3+ and LiB-aBO3 : Tb3+ phosphors were obtained.

[Effect of ambient atmosphere on laser micro-plasma radiant intensity].

The plasma radiant intensity was investigated by a laser micro-plasma spectral analysis system. The system consists of an YJG-II laser micro-spectral analyzer and a CCD data acquisition and processing system. National standard soil samples were studied in the experiment under different ambient atmosphere with argon, helium and the mixture of argon and helium by using the analysis lines, Ca II 393.

[Study of enhancement effect of laser-induced crater on plasma radiation].

Single pulses exported from high-energy neodymium glass laser were used to act on the same position of soil sample surface repeatedly, and the plasma emission spectra generated from sequential laser pulse action were collected by spectral recording system. The experimental results show that the laser-induced soil plasma radiation was enhanced continuously under the confinement effect of the crater walls, and the line intensities and signal-to-background ratios both had different improvements along with increasing the number of acting pulses. The photographs of the plasma image and crater appearance were taken to study the plasma shape, laser-induced crater appearance, and the mass of the ablated sample.

[Effect of charge compensation on emission spectrum of Sr2SiO4 : Dy3+ phosphor].

The Sr2SiO4 : Dy3+ phosphor was synthesized by the high temperature solid-state reaction method in air. Dy2O3 (99.9%), SiO2 (99.

[Enhancing effect of magnetizing solution sample on inductively coupled plasma atomic emission spectrum].

In the present paper, the physics property and nebulization character of the sample solution as well as elemental spectrum intensity were investigated with the prolonging of magnetization time after the water solution with the ethanol was magnetized under magnetic field of 0.24T. The magnetization mechanism was discussed.

[Optics heterodyne detection of the autoionization state of barium].

The autoionization state of barium was observed by optics heterodyne between three-photon resonant nondegenerated six-wave mixing (NSWM) and two-photon resonant nondegenerated four-wave mixing (NFWM). In this way, optics heterodyne spectrum of 6p(3/2) 19d autoionization state of barium was measured. The suppression and enhancement of the NFWM signal was observed which was caused by the quantum interference between NFWM and NSWM.

[The current development of laser-induced plasma spectral analysis technique].

In the present paper, the productions by applying laser-induced plasma spectral analysis technique in different research fields were summarized. Many examples of the application based on laser-induced breakdown spectroscopy (LIBS) and laser-induced plasma spectroscopy (LIPS) methods were introduced, including the substance composition and correlative characteristics of the solid samples (e.g.

[Determination of Al and ca in soil by laser micro-plasma spectroscopy].

Laser micro-spectral analyzer, coupled with CCD spectrometer, was used to determine soil elements in argon atmosphere at reduced pressure in the authors' experiment. The accuracy and availability of this method were studied. With Al I 394.

[Enhancing effect of ethanol additive on the plasma emission in ICP source].

In the present paper, the effects of the ethanol-water solution temperature (20, 40, and 60 degrees C) on the emission intensity of ICP source, plasma parameters (excitation temperature and electron density), physical properties (surface tension and viscosity) of sample solution, and nebulization (uptake rate, effective uptake rate and nebulization efficiency) were studied by using optical-to-electrical detection method. The experimental results showed that the velocity of the sample entering the plasma increased, so that the line intensity of the elements Zn, Fe, Mg, Si, and Sr in water increased obviously with increasing the content of ethanol and the rise of the corresponding solution temperature. And the excitation capacity in the plasma was strengthened with the rise of the ethanol-water solution temperature.

[Effects of argon atmosphere at high pressure on electron temperature of laser-induced Cu plasmas].

Copper plasma was induced with a high energy neodymium glass laser(0-25J) beam ablating the Cu target in argon atmosphere. It was observed that the line intensity of the emission spectra increases when the ambient pressure(0.1-0.

[Effect of nebulizer gas pressure on the emission intensity of ICP].

In an attempt to inhance the emission intensity of ICP, a conventional concentric pneumatic nebulizer was used with increased pressure, and the aqueous aerosol was partially let out to modulate the flow velocity of sample solution into the flame of the ICP. In the present work, the emission spectra of elements Ca, Si, Sr and Zn in water samples were measured, and the results showed that corresponding emission intensities are the highest at 0.05 MPa under the conventional condition, and after increasing the nebulizer gas pressure to 0.

[Enhancement effect of argon atmosphere at high pressure on radiation intensity of laser-induced soil plasmas].

In the present paper, the effects of argon atmosphere at high pressure (0. 2-1.1 MPa) on the radiation intensity of the plasma induced by a high energy neodymium glass laser (energy -30 J, pulse width 0.

[Effect of carbon coating on radiation intensity of laser-induced metal plasmas].

In order to reduce the reflectance of laser beam on sample surface and enhance the radiation intensities of laser-induced metal plasma, a means has been studied for carbon coating on the surface of steel sample. The experimental results showed that the line intensities of the laser plasma formed when a high-energy neodymium glass laser (approximately 25 J) was used to generate the plasma in air at atmospheric pressure increased by a factor in the range of 10%-28% for the steel sample with the carbon coating. The excitation temperature of laser plasma was measured to explain the mechanism that the line intensities increase.