Fluorescence origin and chirality mechanism of graphene quantum Dots: Twist or Non-Twist?

In this paper, we theoretically investigate the fluorescence origin and chirality mechanism of graphene quantum dots with non-twist and twist geometries, respectively. It is revealed that twist is not necessary for fluorescence; but twist is must for the chirality, which can significantly enhance the intensity of chirality, demonstrated by ECD spectra. Our results provide deeper understanding on the physical mechanism of fluorescence and chirality of graphene quantum dot influenced by geometric twist.

Organic Solar Cells: Physical Principle and Recent Advances.

Organic solar cells (OSC) based on organic semiconductor materials that convert solar energy into electric energy have been constantly developing at present, and also an effective way to solve the energy crisis and reduce carbon emissions. In the past several decades, efforts have been made to improve the power conversion efficiency (PCE) of OSCs. During this period, a variety of structural and material forms of OSCs have evolved. Commercializing OSCs, extending their service life and exploring their future development are promising but challenging. In this review, we first briefly introduce the development of OSCs and then summarize and analyze the working principle, performance parameters, and structural features of OSCs. Finally, we highlight some breakthrough related to OSCs in detail.

Efficient full-color emitting carbon-dot-based composite phosphors by chemical dispersion.

Realizing full-color emission plays a key role in exploring the luminescence mechanisms of carbon dots (CDots) and promoting the applications of CDots in light-emitting diodes (LEDs). Herein, a synthesis strategy for full-color emitting CDots was developed through the solvothermal reaction of citric acid and urea with a constant mass ratio but varying reactant concentrations in solvent. With the reactant concentrations increasing, a dual regulation mechanism including an enhanced nucleation growth process and subsequently increased C[double bond, length as m-dash]O/C[double bond, length as m-dash]N-related surface states should be responsible for the photoluminescence (PL) shift of CDots from blue to red. Relying on the hydrolyzation and condensation processes of 3-aminopropyltrimethoxysilane, a simple and universal method was developed by chemically dispersing the CDots into a cross-linked silica network on the surface of SiO2 nanoparticles to produce efficient full-color emitting SiO2/CDot composite phosphors with considerable PL quantum yields in the range of 30-60%. It was proved that the full-color emitting SiO2/CDot composite phosphors could be flexibly applied in packaging white LEDs, releasing pure white light at the Commission Internationale de L'Eclairage (CIE) coordinates of (0.33, 0.33) with a color rendering index (CRI) of 80.4 and a high color-rendering white light coming entirely from CDots with the CIE coordinates of (0.34, 0.36) and a CRI of 97.4, indicating promising application of the full-color emitting SiO2/CDot composite phosphors in the LED field.

[Investigation and analysis of factors influencing rehabilitation of burn patients].

OBJECTIVE: To study the factors influencing health of burn patients in rehabilitation period. METHODS: One hundred and one patients hospitalized in burn department of Xiehe Hospital of Fujian Medical University from February 2008 to October 2008 were investigated by means of General Information Questionnaire, the Eysenck Personality Questionnaire, the Medical Coping Modes Questionnaire, and the Social Support Rating Scale. Their rehabilitation condition was scored according to the Abbreviated Burn-Specific Health Scale. Investigation data were processed by multiple linear regression analysis in order to find out the factors influencing rehabilitation of burn patients. RESULTS: Patients in this group were scored (57 +/- 16) points in physical function, rate [(actual score/possible highest score) x 100%, the same below] 71.1% (the lowest); (97 +/- 19) points in psychological function, rate 80.6%; (53 +/- 8) points in social function, rate 88.4% (the highest); (45 +/- 11) points in general health, rate 74.5%; (251 +/- 44) points in comprehensive health [standard score (314 +/- 55) points], rate 78.5% (upper middle). The factors included in the comprehensive health regression equation (F = 11.602, P < 0.001) were: monthly income, size of burn, number of operations, introverted/extroverted characteristics, living, degree of utilization of support, social support, and resignation. They accounted for 46.6% of the variance of comprehensive health. CONCLUSIONS: Monthly income, size of burn, introverted/extroverted characteristics, living, social support, and resignation are the main factors influencing the rehabilitation level of burn patients.