A new type of hierarchical ZnSnO3-SnO2 flower-shaped nanostructure composed of thin nanoflakes as secondary units is successfully prepared through a simple hydrothermal process. The polyhedral ZnSnO3 core acts as a sa...A new type of hierarchical ZnSnO3-SnO2 flower-shaped nanostructure composed of thin nanoflakes as secondary units is successfully prepared through a simple hydrothermal process. The polyhedral ZnSnO3 core acts as a sacrificed template for the growth of hierarchical SnO2 nanoflakes, and the average thickness of SnO2 nanoflakes is around 25 nm. The time-dependent morphology evolution of ZnSnO3-SnO2 samples was investigated, and a possible formation mechanism of these hierarchical structures is discussed. The gas sensor based on these novel ZnSnO3-SnO2 nanostructures exhibits high response and quick response- recovery traits to ethanol （C2H5OH）. It is found that ZnSnO3-SnO2 nanoflakes have a response of 27.8 to 50×10-6 C2H5OH at the optimal operating temperature of 270 °C, and the response and recovery time are within 1.0 and 1.8 s, respectively.展开更多
Relying on a solvent thermal method, spherical Na2Li2Ti6O14 was synthesized. All samples prepared by this method are hollow and hierarchical structures with the size of about 2-3 μtm, which are assembled by many prim...Relying on a solvent thermal method, spherical Na2Li2Ti6O14 was synthesized. All samples prepared by this method are hollow and hierarchical structures with the size of about 2-3 μtm, which are assembled by many primary nanoparticles （-300nm）. Particle morphology analysis shows that with the increase of temperature, the porosity increases and the hollow structure becomes more obvious. Na2Li2Ti6Ol4 obtained at 800℃ exhibits the best electro- chemical performance among all samples. Charge-discharge results show that Na2Li2Ti6O14 prepared at 800℃ can delivers a reversible capacity of 220.1, 181.7, 161.6, 144.2, 118.1 and 97.2 mA h g-1 at 50, 140, 280, 560, 1400, 2800 mA g-1. How- ever, Na2Li2Ti6O4-bulk only delivers a reversible capacity of 187, 125.3, 108.3, 88.7, 69.2 and 54.8 mA h g-1 at the same current densities. The high electrochemical performances of the as-prepared materials can be attributed to the distinctive hollow and hierarchical spheres, which could effectively reduce the diffusion distance of Li ions, increase the con- tact area between electrodes and electrolyte, and buffer the volume changes during Li ion intercalation/deintercalation processes.展开更多
Recapitulation of well-defined α-helices could result in constrained peptide mimetics with preferable secondary structures and enhanced therapeutic properties for various purposes. Among the helix-stabilizing strateg...Recapitulation of well-defined α-helices could result in constrained peptide mimetics with preferable secondary structures and enhanced therapeutic properties for various purposes. Among the helix-stabilizing strategies, the nucleation strategies are able to maximize recognition specificity of the original sequence without compromising the molecular recognition surface. In this review,current methodologies of helix nucleation are introduced including their constructing strategies, structure features and proof of concept biological applications.展开更多
基金Projects (50832001, 51002014) supported by the National Natural Science Foundation of ChinaProject (20110491319) supported by China Postdoctoral Science Foundation
文摘A new type of hierarchical ZnSnO3-SnO2 flower-shaped nanostructure composed of thin nanoflakes as secondary units is successfully prepared through a simple hydrothermal process. The polyhedral ZnSnO3 core acts as a sacrificed template for the growth of hierarchical SnO2 nanoflakes, and the average thickness of SnO2 nanoflakes is around 25 nm. The time-dependent morphology evolution of ZnSnO3-SnO2 samples was investigated, and a possible formation mechanism of these hierarchical structures is discussed. The gas sensor based on these novel ZnSnO3-SnO2 nanostructures exhibits high response and quick response- recovery traits to ethanol （C2H5OH）. It is found that ZnSnO3-SnO2 nanoflakes have a response of 27.8 to 50×10-6 C2H5OH at the optimal operating temperature of 270 °C, and the response and recovery time are within 1.0 and 1.8 s, respectively.
基金supported by the National Natural Science Foundation of China (21301052 and 51404002)Natural Science Foundation of Heilongjiang Province (E2016056)+2 种基金Specialized Research Fund for the Doctoral Program of Higher Education (20132301120001)Postdoctoral Science-Research Developmental Foundation of Heilongjiang Province (LBH-Q13138)Applied Technology Research and Development Program of Harbin (2015RAQXJ032)
文摘Relying on a solvent thermal method, spherical Na2Li2Ti6O14 was synthesized. All samples prepared by this method are hollow and hierarchical structures with the size of about 2-3 μtm, which are assembled by many primary nanoparticles （-300nm）. Particle morphology analysis shows that with the increase of temperature, the porosity increases and the hollow structure becomes more obvious. Na2Li2Ti6Ol4 obtained at 800℃ exhibits the best electro- chemical performance among all samples. Charge-discharge results show that Na2Li2Ti6O14 prepared at 800℃ can delivers a reversible capacity of 220.1, 181.7, 161.6, 144.2, 118.1 and 97.2 mA h g-1 at 50, 140, 280, 560, 1400, 2800 mA g-1. How- ever, Na2Li2Ti6O4-bulk only delivers a reversible capacity of 187, 125.3, 108.3, 88.7, 69.2 and 54.8 mA h g-1 at the same current densities. The high electrochemical performances of the as-prepared materials can be attributed to the distinctive hollow and hierarchical spheres, which could effectively reduce the diffusion distance of Li ions, increase the con- tact area between electrodes and electrolyte, and buffer the volume changes during Li ion intercalation/deintercalation processes.
基金supported by the Natural Science Foundation of China (21372023, 81572198)Ministry of Science and Technology of China (2015DFA31590)+1 种基金the Shenzhen Science and Technology Innovation Committee (JSGG20140519105550503, JCYJ20150331100849958, JCYJ20150403101146313, JCYJ20160301111338144, JSGG20160301095 829250)the Shenzhen Peacock Program (KQTD201103)
文摘Recapitulation of well-defined α-helices could result in constrained peptide mimetics with preferable secondary structures and enhanced therapeutic properties for various purposes. Among the helix-stabilizing strategies, the nucleation strategies are able to maximize recognition specificity of the original sequence without compromising the molecular recognition surface. In this review,current methodologies of helix nucleation are introduced including their constructing strategies, structure features and proof of concept biological applications.
