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Aim Climate change is expected to have important effects on plant phenology and carbon storage, with further shifts predicted in the future. Therefore, we proposed the community carbon accumulation rate (CAR) from the start of the growing season (SOS) to the peak of the growing season (POS) to fill the gap that the dynamic interactions between plant phenology and plant carbon research. Location Tibetan Plateau. Major taxa Alpine grassland plants. Time period 2015. Methods We conducted a transect survey across grasslands to measure community aboveground net primary production and carbon concentration. Additionally, phenology indicator data (SOS and POS) were extracted from the Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index version 3 database. Next, we used 'changepoint' analysis to detect the patterns of CARs, and performed linear regression and one-way ANOVA to explore the variability of CARs in response to the environmental factors. Ultimately, the total effects of environmental factors on CARs were illustrated by a structural equation model. Results Our results indicated that three CAR patterns were detected, which are low-CAR (0.15 g/m(2)/day), medium-CAR (0.31 g/m(2)/day) and high-CAR (0.84 g/m(2)/day) patterns. We found that the availabilities of water and heat mediated CARs by regulating soil nutrition variability, and that drought climate and insufficient soil resources co-constrained the community CAR at long time-scales. In contrast, high CAR could be explained by more water and heat availability via either direct or indirect effects on soil moisture and soil nutrients. Main conclusions Our findings highlight that water and heat availability are critical driving factors in ecological carbon accumulation processes undergoing climate change. Meanwhile, the vegetative phenology also has important effect on carbon accumulation. Consequently, we propose incorporating the dynamic interactions between plant phenology and plant carbon into the ecological carbon cycle model to improve our understanding of resource utilization and survival strategies of plants under environmental change.

5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I) was synthesized by reaction of 5-amino-tetrazole with ethyl cyanoacetate in excellent yield. A series of novel 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol dyes were prepared by linking o-, m-, p-anisidine, o-, m-, p-chloroaniline, o-, m-, p-nitroaniline, o-, m-, p-toluidine and aniline to 5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I). The structure of these dyes were confirmed by UV-vis, FTIR and 1H NMR spectroscopic techniques and elemental analysis. The effect of varying pH and solvent upon the absorption ability of 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol sudstituted with electron-withdrawing and electron-donating groups at their o-, m-, p-position was examined.

Ternary-/hetero-nanocrystals: a facile one-pot colloidal route for controlled synthesis of ternary AgFeS2 nanocrystals, which have a band gap of 1.21 eV, is presented for the first time. Such ternary AgFeS2 nanocrystals can transform to Ag2 S-Fe7 S8 heterodimers by internal thermal reaction at elevated temperature, providing a new route to synthesize semiconductor hetero-nanostructures.

Polymer granules are conveyed and plasticized using an innovational vane extruder composed of several vane plasticizing and conveying units (VPCUs). This study developed a mathematic model to analyze the bulk density of polymer granules in a VPCU, as well as conducted an experiment to investigate the effects of device geometry, polymer properties, and operating conditions on the model. By comparing the theoretical model data with the experiment data, the proposed model of bulk density is found to be aligned with actual conditions, thus providing a basis for device and process optimization. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 842-850, 2013

Playing six-a-side: Complex hexagonal prism Cu(1.94)S-ZnS heteronanostructures were synthesized by a colloidal route. Cu(1.94)S-ZnS, Cu(1.94)S-ZnS-Cu(1.94)S, and Cu(1.94)S-ZnS-Cu(1.94)S-ZnS-Cu(1.94)S structures are formed with screw-, dumbbell-, and sandwich-like shapes by using CuI and [Zn(S(2)CNEt(2))(2)] as precursors in oleylamine.

The reaction of trialkylphosphines with a series of nanostructured chalcogenides results in metals and metal-sulfide heterostructures.

The solar flare occurred on April 2, 2001 is the biggest flare in 23rd cycle of solar activity, which is companied by a big solar proton event. We study this event by combining the observational results from spacecraft SZ2/XD and satellite ZY1/CBMC. SZ2 has the orbit with 400 km height and inclination of 42degrees, and ZY1 has solar-synchronous orbit and 780km to the Earth surface. The results show that after this flare ZY1/CBMC detected the flare particles in the polar cap region and XD observed an increase of energetic electron flux near the latitude 42degrees. Morphological analysis of the temporal and spatial variations of energetic particles after this flare indicates that particles in different regions have varied origins. Those in the polar cap region come from the Earth's open field lines and those in the auroral oval and mid-latitudes near 42degrees are particles of the Earth's outer radiation belt. Data analysis and comparison show that the intensity of the solar proton event is not proportional to the X ray flux of the related solar flare. The response of energetic particles in the near Earth space is not solely related with solar X ray intensity.

From February to June in 2001, there are two instruments for energetic particle detections on board of ZY1 (CBERS-1) and SZ2 respectively. In this paper, data of energetic electrons from ZY-1/CBMC and SZ2/XD were compared for this same period. The energetic electron data from SZ-2 by a X-ray detector (XD) gives electron distribution at a height of 400 km with a declination of 42degrees, while Energetic Particle Detector in side the cabin of ZY-1 is on a polar orbit at a height of 800km, giving the global distribution of electrons of 0.5 similar to 2MeV. The results of the comparison showed that, although the height is different, the lowest latitudes where the energetic electrons are observed and the longitudinal distribution are almost the same. This indicates that down to an altitude around 400km, the energetic electrons are still controlled by geomagnetic field. This also shows that a coordinated analysis of data from these two satellite series are very helpful for understanding the lower part of earth's radiation belts.

5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I) was synthesized by reaction of 5-amino-tetrazole with ethyl cyanoacetate in excellent yield. A series of novel 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol dyes were prepared by linking o-, m-, p-anisidine, o-, m-, p-chloroaniline, o-, m-, p-nitroaniline, o-, m-, p-toluidine and aniline to 5-amino-tetrazolo[1,5-a]pyrimidin-7-ol (I). The structure of these dyes were confirmed by UV-vis, FTIR and 1H NMR spectroscopic techniques and elemental analysis. The effect of varying pH and solvent upon the absorption ability of 5-amino-6-arylazotetrazolo[1,5-a]pyrimidin-7-ol sudstituted with electron-withdrawing and electron-donating groups at their o-, m-, p-position was examined.