ABSTRACT
As the promising anode material of lithium-ion batteries (LIBs), SiO2 has high theoretical capacity, but the volume expansion severely hinders its application. To address the challenge, inspired by the highly flexible spider-web architecture, the SiO2@carbonized polyaniline/carbonized 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (SiO2@cPANI/cTOCNFs) composite was designed, and fabricated via carbonizing the freeze-dried SiO2@PANI/TOCNFs. The resultant SiO2@cPANI/cTOCNFs composite exhibited unique spider-web-like nanostructures, providing a double-layer carbon network to protect SiO2 anode material. The results showed that, the SiO2@cPANI/cTOCNFs composite as anode material of LIBs offered a reversible capacity of 1103 mAh g-1 at a current density of 0.1 A g-1 after 200 cycles, and gave a capacity of 302 mAh g-1 after 1000 cycles at a current density of 1 A g-1, exhibiting excellent cycling stability. This study provides a strategy of spider-web-inspired cellulose nanofibrils networking polyaniline-encapsulated silica nanoparticles as anode material of LIBs.
ABSTRACT
The rapid global construction of ecological engineering has had an important impact on hydrological processes, especially in China. However, previous studies have largely regarded the hydrological system as a "black box" and have formed conclusions by comparing changes before and after ecological engineering; additionally, managers have assumed that the intensity of ecological engineering (IEE) is proportional to the hydrological system effect. The influence processes and mechanisms of the IEE on hydrological systems are unclear. Here, the source region of the Yangtze River (SRYR) in China was adopted as the empirical research area. Based on various data, such as DEM, soil, land use and climate data from 1980 to 1987 and 2004-2015, a Soil and Water Assessment Tool (SWAT) model was constructed, and the response of the hydrological system to the IEE was quantitatively explored. The results showed that the IEE generally displayed an increasing trend, increasing from 10.209 in 2005 to 10.649 in 2015. There was no linear relationship between the IEE and hydrological effects, and the hydrological effects did not increase with increasing IEE but did exhibit obvious stages. Specifically, the four phases - the lag phase, transition phase, sensitive phase, and adaptive phase - had different hydrological response characteristics, sensitivities, structures, and functions. Based on the feedback of the hydrological system, ecological engineering managers should abandon the incorrect assumption of a linear relationship between the two and realize that there is usually a lag phase in the early implementation of ecological engineering that requires a continuous increase in the IEE. Additionally, managers should choose the appropriate IEE, evaluation nodes and periods and prioritize the most sensitive hydrological variables in different stages based on the evaluation purpose and hydrological response, thereby improving the efficiency of ecological engineering and realizing the original goal of ecological protection and restoration.
Subject(s)
Hydrology , Rivers , China , Climate , Climate Change , SoilABSTRACT
14-3-3 Proteins are a family of highly conserved regulatory molecules expressed in all eukaryotic cells and regulate a diverse set of biological responses in plants. However, their functions in flowering of Phyllostachys violascens are poorly understood. In this study, four non-ð Pv14-3-3 genes from P. violascens were identified and named PvGF14b, PvGF14c, PvGF14e, and PvGF14f. qRT-PCR analyses revealed that PvGF14b and PvGF14e exhibited widely expressed in all tested bamboo tissues. PvGF14b was highest expression in root and lowest in immature leaf. Whereas PvGF14c and PvGF14f showed tissue-specific expression. PvGF14c was mainly expressed in immature and mature leaves. PvGF14f was highest expression in mature leaves. These four genes were not significantly differentially expressed in mature leaf before bamboo flowering and during flower development. PvGF14b and PvGF14c were not induced by circadian rhythm. PvGF14c displayed subcellular localization in the cytoplasm and PvFT in nucleus and cytoplasm. Yeast two-hybrid screening and bimolecular fluorescence complementation confirmed the interaction between PvGF14c and PvFT. The overexpression of PvGF14b, PvGF14c, and PvGF14e significantly delayed flowering time in transgenic Arabidopsis under long-day condition. These findings suggested that at least three PvGF14 genes are involved in flowering and may act as a negative regulator of flowering by interacting with PvFT in bamboo.
ABSTRACT
The contributions of climate and land use change (LUCC) to hydrological change in Heihe River Basin (HRB), Northwest China were quantified using detailed climatic, land use and hydrological data, along with the process-based SWAT (Soil and Water Assessment Tool) hydrological model. The results showed that for the 1980s, the changes in the basin hydrological change were due more to LUCC (74.5%) than to climate change (21.3%). While LUCC accounted for 60.7% of the changes in the basin hydrological change in the 1990s, climate change explained 57.3% of that change. For the 2000s, climate change contributed 57.7% to hydrological change in the HRB and LUCC contributed to the remaining 42.0%. Spatially, climate had the largest effect on the hydrology in the upstream region of HRB, contributing 55.8%, 61.0% and 92.7% in the 1980s, 1990s and 2000s, respectively. LUCC had the largest effect on the hydrology in the middle-stream region of HRB, contributing 92.3%, 79.4% and 92.8% in the 1980s, 1990s and 2000s, respectively. Interestingly, the contribution of LUCC to hydrological change in the upstream, middle-stream and downstream regions and the entire HRB declined continually over the past 30 years. This was the complete reverse (a sharp increase) of the contribution of climate change to hydrological change in HRB.