[Analysis of effect of military outpatients' psychological feelings on doctor-patient relationship in orthodontic treatment].

PURPOSE: To explore the effect of military outpatients' psychological feelings on doctor-patient relationship in orthodontic treatment. METHODS: A total of 95 clinic patients who were undergoing orthodontic treatment were asked to complete the questionnaire of dental visit satisfaction scale (DVSS) and orthodontist-patient relationship scale (OPRS). The results of different groups according to identity, gender, age and treatment time were compared. The data was analyzed with SPSS 20.0 software package for correlation analysis and stepwise regression. RESULTS: Except 6-18 months group, psychological feelings of patients had significant impact on doctor-patient relationship (P<0.01). The correlation coefficient was 0.610 between patients' satisfaction of outpatient treatment and doctor-patient relationship (P<0.001). Among 9 psychological feelings of orthodontic treatment, five kinds had significant effect on doctor-patient relationship, including three kinds of positive correlation and two kinds of negative correlation. CONCLUSIONS: The patients' psychological feelings are closely related to doctor-patient relationship. Doctors should try to improve medical quality, strengthen service level and pay much attention to the patients' psychological and social needs.

[Study on the excitation mechanism of upconversion red emission from Er3+ under square wave excitation].

The rise and decay curves of Er3+ 4F9/2 upconversion emission in oxyfluoride tellurite glass were measured under the excitation at 808 nm from a laser diode driven by square waves. The lifetime of the intermediate state could be determined via rise times. Then the accumulation process of the 4F9/2 population was confirmed. The excitation mechanism of up-conversion red emission under 808 nm excitation was confirmed by the rate equations and analyzing the relationship between the time constants of the rise and decay processes and the intermediate state. Square wave excited upconversion emission may also be used for measuring lifetimes of infrared energy levels with a conventional photomultiplier tube.

[Electrooptical properties of nanoscale and bulk SrAl2O4: Eu, Dy].

Nanoscale and bulk SrAl2O4 : Eu2+, Dy3+ were prepared respectively by auto-combustion of citrate gelatin and high temperature solid state method. The crystalline structure was examined by X-ray diffraction (XRD). The current-voltage characteristic was measured with a Keithley source meter 2 410. The VUV spectra were carried out with VUV spectrometer. There-result showed that light irradiation increased the current, which indicates that some electrons are excited to the conduction band of host lattice. VUV excitation spectrum of nanoscale SrAl2O4 : Eu2+, Dy3+ shifts to the shorter wavelength relative to bulk material because it has narrower bandgap. As a result, the current of nanoscale material is weaker than that of the bulk one.

[The effect of temperature on the 4f5d emission of Pr3+ in the Pr3+-doped SrAl12O19].

The emission spectra of SrAl12O19 : Pr3+ at temperature from 308 to 483 K were investigated under vacuum ultraviolet excitation. Both the dipole-forbidden 4f2 --> 4f2 transition and the dipole-allowed 4f5d --> 4f2 transitions were observed. The intensity of the 4f5d --> 4f2 emission relative to that of the 4f2 --> 4f2 emission increased with increasing temperature. A thermal equilibrium model was applied to the system consisting of the 1S0 state and the lowest 4f5d states of Pr3+, and the temperature dependence of emission spectra of Pr3+ in the Pr(3+)-doped SrAl12O19 was well explained.

[Investigation on electroluminescence of MEH-PPV/ZnSe nanocomposite device].

ZnSe nanocrystals were synthesized in aqueous solution by using mercapto-acetate acid as stabilizer. Products were characterized by X-ray diffraction patterns (XRD) and X-ray photoelectron spectra (XPS). A surfactant was used to transfer the nanocrystals from the aqueous solution to organic solvent, so that ZnSe and MEH-PPV could be mixed sufficiently and were used as an emitting layer in a multilayered electroluminescence device: Glass/ITO/MEH-PPV : ZnSe /BCP/Alq3/LiF/Al. A comparison between absorption spectra and photoluminescence spectra of ZnSe nanocrystals and MEH-PPV thin film exhibits an effective energy transfer from ZnSe nanocrystals to MEH-PPV, which is one reason for the existing difference between photoluminescence spectrum and electroluminescence spectrum of MEH-PPV : ZnSe nanocomposite film. The recombination mechanism of the nanocomposite film under photoexcitation and electric injection was discussed respectively. The authors investigated the photo- and electroluminescence properties of the device, and found that the EL intensity of ZnSe nanocrystals increased with the applied voltages. The I-V characteristic of this device is similar to that of a classic diode.

[A new measurement method of time-resolved spectrum].

A new method for measuring time-resolved spectrum (TRS) is brought forward. Programming with assemble language controlled the micro-control-processor (AT89C51), and a kind of peripheral circuit constituted the drive circuit, which drived the stepping motor to run the monochromator. So the light of different kinds of expected wavelength could be obtained. The optical signal was transformed to electrical signal by optical-to-electrical transform with the help of photomultiplier tube (Hamamatsu 1P28). The electrical signal of spectrum data was transmitted to the oscillograph. Connecting the two serial interfaces of RS232 between the oscillograph and computer, the electrical signal of spectrum data could be transmitted to computer for programming to draw the attenuation curve and time-resolved spectrum (TRS) of the swatch. The method for measuring time-resolved spectrum (TRS) features parallel measurement in time scale but serial measurement in wavelength scale. Time-resolved spectrum (TRS) and integrated emission spectrum of Tb3+ in swatch Tb(o-BBA)3 phen were measured using this method. Compared with the real time-resolved spectrum (TRS). It was validated to be feasible, credible and convenient. The 3D spectra of fluorescence intensity-wavelength-time, and the integrated spectrum of the swatch Tb(o-BBA)3 phen are given.

[Study on the property of CBD-CdS thin films].

CdS thin films were prepared by chemical bath deposition (CBD) at 90 'C. The influence of annealing and CdCl2 treatment on CBD-CdS thin film was studied. XRD and SEM were used to study the crystal structure and surface morphology ofthe films. The untreated CBD-CdS films had poor crystallinity; the CdS thin film made with annealing treatment had cubic crystallinity but small grain size. After the CdCl2 treatment, these films recrystallized to the hexagonal phase, resulting in a better crystallinity, and smooth surface morphology. Optical properties were studied by absorption spectrum. The energy gap of the films was found to decrease by annealing, and the CBD-CdS made with CdCl2 treatment had a lower density of planar defects. In conclusion, the CdCl2 treatment can improve the properties of the CdS thin films.

[The analysis of sinusoidal modulated method used for measuring fluorescence lifetime].

This paper has built a system with a sinusoidal modulated LED as the excitation source. Such exciter was used upon the sample Eu2 L'3 x nH2O (L' = C4H4O4). Both the excitation light and the 5Do-7F2 emission of Eu3+ ion were measured. Fluorescence lifetime, which approximate to 0.680 ms, can then be obtained from the measured excitation and fluorescence waveforms by non-linear least square curve fitting based on the principle of phase-shift measurement of fluorescence lifetime. Data processing methods considering respectively the high order harmonics in the modulation and multi-exponential decay of the fluorescence were discussed. A method of utilizing Fourier series expandedness to amendatory the result was put forward. Accordingly, the applicability for phase-shift method was expanded as well as a more exact result was acquired.

[Spectrum and synthesis of rare earth activated nanoparticle].

La2O3: Eu(3+) nanoparticles were prepared by Gly assistant combustion synthesis with the sizes from 12-28 nm, and a characterization of XRD was done. Spectral properties of the nanoparticles were compared with the bulk. High resolution spectra were measured. Site selective excitation was employed to probe the local environments of Eu(3+) ions in La2O3 nanoparticles. The luminescent centers on the surface and the center of the nanoparticles were excited respectively. The spectra were related to surface information. The luminescence from C3v site and the site with lower symmetry on the surface was distinguished.

[Study of luminescence properties of nano-size ZnO embedded in SiO2 layer grown by radio-frequency magnetron sputtering].

Nano-size ZnO embedded in SiO2 layers were grown by radio-frequency magnetron sputtering. Absorption spectra and PL spectra were employed to study the optical character of the samples at room temperature. Absorption spectra blue-shifted when the size of nano-meter ZnO decreased, which indicated that quantum size effect became stronger with decreasing the size of ZnO. PL spectra show two peaks at about 387 and 441 nm, respectively. It was concluded that the UV emission originates from the radiative recombination of free-exciton, and the blue emission is due to the electron transition from donor levels of oxygen vacancies to the top of valence band. The origin of the two peaks is demonstrated by time-resolved spectra and luminescence decay curve.

[Influence of novel surface treatment of ITO anodes on the performance of OLED].

The influences of surface treatments of indium-tin-oxide (ITO) anodes on the performance of OLED devices were investigated. This surface treatment is mechanical processes using a novel nanometer powder. Their surface morphology was measured by scanning using an AFM (atomic force microscope). The number and size of spike was reduced and regulation of ITO was enhanced; brightness and efficiency of devices were obviously increased. This novel way for ITO surface treatment by mechanical processes was proven to be effective.

[Preparation and room temperature emission of nanocrystalline ZnO: Er3+].

The nanocrystalline ZnO:RE powders with room temperature sharp photoluminescence were prepared successfully by chemical precipitation method in the present work. This is a great progress in the study of rare earth doped ZnO. For the ZnO:Er3+ obtained in the present paper, the room temperature sharp characteristic emissions from the trivalent rare earth Er3+, including upconversion and near infrared emission, and the energy transfer between the nanocrystalline ZnO host and the dopants were observed.

[Photoluminescent and electroluminescent properties of a new rare earth terbium complex].

Pure green and narrowbandwidth emission from an organic electroluminescent device was presented by using arare earth terbium (III) complex as the emissive layer. The structure of the device was ITO/PVK/Tb/PBD/LiF/Al. It was proved that this new kind of rare earth complex has excellent photoluminescent and electroluminescent properties. The electroluminescent spectrum of the device was very similar to that of the terbium (III) complex film. The electroluminescent mechanism of the device was proposed by measuring and analyzing the spectra and electroluminescent property of the device. It is proposed that the excited carriers of PVK and PBD were captured by Tb3+ and light was emitted when the electrons and holes recombined at Tb3+.

[Optical properties of core-shell ZnS :Mn nanoparticles].

Mn(2+)-doped ZnS nanoparticles were prepared in reverse micelles and were coated by a shell of ZnS. The optical properties of the coated Mn(2+)-doped ZnS nanoparticles were studied and compared with those of the uncoated ones. The results indicate that Mn2+ ions emission at 580 nm in the coated nanoparticles was much stronger than that in the uncoated ones. The excitation spectra of the uncoated nanoparticles shifted to the red with the time after the initial preparation, while those of the coated ones changed little, which indicate that the coated nanoparticles had better stability than the uncoated ones.

[High efficiency and low threshold upconversion from IR to red for Er3+ and Tm3+ co-doped fluoride-oxide glass-ceramic].

In this paper, high efficiency and low threshold upconversion from IR to red is reported, for Er3+ and Tm3+ co-doped fluoride-oxide glass-ceramic under 978 nm LD excitation. The component of sample in experiment is 65GeO2-25NaF-8.5BaF2-1Er2O3-0.5 Tm2O3, and the prepared method is obtained. The upconversion emission spectra under 978 nm LD excitation is measured at room temperature. Analyzing it, we find that introduction of Tm3+ into Er3+ doped system preferentially quenches the green upconversion fluorescence from 4S3/2 level of Er3+ duo to the efficient cross-relaxation of 4I13/2-->4I15/2 (Er): 3H6-->3H4 (Tm) which can significantly reduce the upconversion efficiency from 4I13/2 level to the emitting 4S3/2 level, and the Tm3+ behaves as a good sensitizer of the red upconversion from the 4F9/2 level of Er3+ which is mainly populated by the cross-relaxation of 3H4-->3H6 (Tm): 4I11/2-->4F9/2 (Er). However, at low Er3+ concentration (2 mol%), it is impossible for strong red upconversion. X-ray analysis is done, there are lots of nanocrystallites in MFG glass-ceramic. So we think, this red upconversion is attributed to Er3+ enriched fluoride microcrystallites, which makes the cross-relaxation of 3H4-->3H6 (Tm): 4I11/2-->4F9/2 (Er) more effective, therefore their active optical properties may be optimised. In the end, the relationship between LD working current and intensity of upconversion luminescence is discussed, the results confirm that both red and green upconversion processes are consisted by two photons.