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Spatial information of crop area statistics is of great significance for study of global change, population, resources, environment, ecology and food security. In this paper, based on MODIS NDVI time series data and global optimization algorithm SCE-UA (Shuffled Complex Evolution-University of Arizona), the research of spatialization of crop area statistical data was carried out in 13 counties which were located in Shijiazhuang City of Huanghuaihai Plain. The research crop was winter wheat. At last, the accuracy of the result of spatialization of crop area statistical data crop was validated. The final results showed that the regional accuracy of optimal winter wheat distribution map was 99.71% and pixel accuracy kappa coefficient was 0.898. It proved that the method of spatialization of crop area statistical data using the NDVI time-series data and global optimization algorithm SCE-UA was reasonable and feasible. The spatial crop map with higher accuracy could be gotten using this method which was more significant to solve the spatialization of crop area statistical data.

This paper reports that the synthesis and luminescence characteristics of Eu{sup 2+} activated calcium magnesium chlorosilicate, Ca{sub 8}Mg(SiO{sub 4}){sub 4}Cl{sub 2}, have been reported and analyzed. The emission spectrum of Eu{sup 2+} is composed to two separate bands with peaks at 507 and 428 nm, which result from the Eu{sup 2+} centers in different crystallographic sites. At room temperature, the excitation spectrum of the very strong 507 nm emission shows not only the broad 4f{sup 7}-4f{sup 6}5d excitation bands, but also the fine structure resulting from the splitting of 4f{sup 6} configuration in the 4f{sup 6}5d excited state. This structure is explained by the high covalency degree of the cation-anion bonds in this system. Efficient energy transfer between the two inequivalent Eu{sup 2+} centers has been evaluated quantitatively.

In order to acquire the spatial information of winter wheat harvest index (HI), depending on the crop growth profile of time-series MODIS-NDVI to calculate mean slope of NDVI curve and accumulated NDVI at stage of before anthesis and after anthesis, the authors made full use of remote sensing information and structured two parameters HINDVI-k and HINDVI-SUM according to the definition of HI of crop. Then relationships between the two parameters and field measured HI of winter wheat were established respectively. After validation of retrieved winter wheat HI, it was shown that the accuracy of the retrieved HI of winter wheat was high and satisfied at large scale in study region of Huanghuaihai Plain in China. The mean relative errors of the retrieved HI were 3.60% and 2.40% and RMSE were 0.04 and 0.02 respectively. It was proved that the method of structuring parameters of HINDVI-k and HINDVI_SUM and extracting harvest index for winter wheat based on timeseries MODIS-NDVI was reasonable and feasible.

Ce 3+ - and Tb 3+ -doped rare earth borate glasses were synthesized and their luminescence properties have been studied. The sample containing Ce 3+ ions has a strong purplish-blue emission and that doped with Tb 3+ emits a green light under UV excitation. The Ce 3+ ions in the host form two kinds of emission centers, owing to different lattice sites occupied by Ce 3+ in the host glass. In the Ce 3+ and Tb 3+ co-activated samples the Ce 3+ ions strongly sensitize the luminescence of the Tb 3+ ions.

This paper reports that the synthesis and luminescence characteristics of Eu{sup 2+} activated calcium magnesium chlorosilicate, Ca{sub 8}Mg(SiO{sub 4}){sub 4}Cl{sub 2}, have been reported and analyzed. The emission spectrum of Eu{sup 2+} is composed to two separate bands with peaks at 507 and 428 nm, which result from the Eu{sup 2+} centers in different crystallographic sites. At room temperature, the excitation spectrum of the very strong 507 nm emission shows not only the broad 4f{sup 7}-4f{sup 6}5d excitation bands, but also the fine structure resulting from the splitting of 4f{sup 6} configuration in the 4f{sup 6}5d excited state. This structure is explained by the high covalency degree of the cation-anion bonds in this system. Efficient energy transfer between the two inequivalent Eu{sup 2+} centers has been evaluated quantitatively.

Ce 3+ -doped alkaline earth thiogallates with blue emission have been intensively investigated to fabricate full-color thin film electroluminescence (TFEL) devices, with sputtering, atom layer epitaxy (ALE) and molecular beam epitaxy (MBE) being the methods used. In this paper, a new way of preparing CaGa 2 S 4 :Ce TFEL devices, based on inter-layer reaction is first reported. CaS:Ce and Ga 2 S 3 were deposited by electron beam evaporation, layer by layer, and CaGa 2 S 4 :Ce thin film was formed by post processing. The results of X-ray diffraction, scanning transmission electron microscopy (STEM) microphotographs and energy dispersive X-ray spectroscopy (EDX) show that CaGa 2 S 4 :Ce thin film with good crystallinity and stoichiometry were obtained. Photoluminescence (PL) and electroluminescence (EL) of these devices were investigated.

The effect of biochar on soil respiration (Rs) over one maize-growing season was studied after 5 years of consecutive application in an intensive cropland in the North China Plain. The experiment was carried out in randomly arranged plots with four treatments being evaluated. Three replications were conducted per treatment: a control plot without biochar addition (CK), biochar incorporated at 4.5 t ha–1 year–1 (BC4.5), biochar incorporated at 9.0 t ha–1 year–1 (BC9.0), and incorporated wheat straw (SR). The Rs was determined throughout the growing season of maize in 2012. Soil temperature and moisture were measured simultaneously at 5 cm depth. The results showed that the seasonal and diurnal variations of Rs in the four different treatments were approximately equal, and there was a positive correlation between Rs and soil temperature. The Rs values of treatments BC4.5 and BC9.0 were significantly lower than of SR but not CK. Significant correlations between Rs and soil temperature and soil moisture were observed. Soil temperature had a stronger effect on Rs than did soil moisture, and Rs was more sensitive to soil temperature in the biochar treatments than in the SR and CK treatments. The application of biochar and straw increased the soil active organic carbon content, but an obvious relationship between Rs and the soil active organic carbon content was not found.

Er3+-doped and Er3+/Yb3+-codoped Na2O·Ca3Al2Ge3O12 glasses that are suitable for use in optical waveguide devices have been fabricated and characterized. The density, the refractive indices, the optical absorption, the Judd–Ofelt parameters, and the spontaneous transition probabilities of the glasses have been measured and calculated. Intense 1.533-µm fluorescence was observed in these glass systems under 798- and 973-nm excitation, and the quantum efficiency was ∼100%. Efficient upconversion luminescence at 525, 547, and 659 nm at room temperature was also observed. At a pump intensity of 1220 W/cm2 at 798 nm, frequency upconversion efficiencies of 0.98×10-2 and 1.03×10-2 were obtained for green and red emissions, respectively. The standardized value for green emission is higher than those reported for lead germanate, lead tellurium germanate, silicate, and phosphate glasses. Under 973-nm excitation, the enhancement of 1533-nm emission and visible upconversion fluorescence in Er3+/Yb3+-codoped glasses are confirmed, and the sensitizing is due to efficient energy transfer from Yb3+ to Er3+.

The excitation and emission spectra and the charge transfer bands of the Sm(3+) and Eu(3+) in Mg3BO3F3 have been investigated under UV radiation and CR excitation. The charge transfer bands of Sm(3+) and Eu(3+) which center around at 43.5 and 34.2 X103cm-1, respectively are observed at room temperature

The Ce3+ excitation spectrum, the Tb3+ flourescence lifetime and Tb3+→Ce3+ energy transfer in Y3Ga5O12:Ce3+,Tb3+ have been studied under the excitation of ultra-violet radiation containing 266.0 nm laser pulses at room temperature.