Dextran coated magnetic nanocomposites were prepared. A periodate oxidation method was used to further activate the magnetic dextran, forming magnetic polyaldehyde dextran, which could be conjugated to biomolecules, a...Dextran coated magnetic nanocomposites were prepared. A periodate oxidation method was used to further activate the magnetic dextran, forming magnetic polyaldehyde dextran, which could be conjugated to biomolecules, antibodes. The magnetic labeled nano scaled bioconjugates could be well blocked with BSA and exhibit high activity by ELISA and immunochromatographic strip assay.展开更多
Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of...Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of Li x Mn 2 O 4 were investigated.It was shown that the higher the calcination temperature,the more complete the crystal structure,and the larger the partic le size.Moreover,the influence of c alcination time on the crystal structure was insignificant when it was more than 3h at 700℃.With the increase of x in Li x Mn 2 O 4 in the range of 0.6～1.0,the d 111 and lattice parameter a increased fi rst and then decreased.The electrochemical properties of nano-spinel LiMn 2 O 4 using as cathode material of lithium-ion battery were studied.The low di scharge capacity might be due to the irreversible capacity loss brou ght by the large surface area and latt ice vacancies of the nano-spinel.展开更多
The Mengzhuang site lies on a terrace east of Mengzhuang town in southeastern Huixian city, Henan, and occupies an area of 300,000 sq m. It was excavated in 1992-1995, which led to the revelation of remains of the Pei...The Mengzhuang site lies on a terrace east of Mengzhuang town in southeastern Huixian city, Henan, and occupies an area of 300,000 sq m. It was excavated in 1992-1995, which led to the revelation of remains of the Peiligang, Yangshao, Longshan and Erlitou cultures. Those of the Longshan culture include one city-site, 16 house-foundations, numerous ash-pits and four wells. Among the unearthed Longshan objects are: stone tools - the axe, spade, adze, knife, arrowhead, and chisel; bone implements - the arrowhead, awl, chisel, and spoon ; shell artifacts - the knife and arrowhead ; and pottery-the jar, yah steamer, jia tripod, gui tripod, urn, zeng steamer, basin, vessel stand, cup, vessel cover, bowl, dou stemmed vessel, ring-foot dish, zun-shaped object, li tripod and ding tripod. The whole complex can be divided into two phases, which are dated to 2400--2300 and 2300--2100 BC respectively.展开更多
LiCoO2 precursors of the cathode material for lithium ion batteries were prepared from lithium hydroxide, basic cobalt carbonate and citric acid by a sol gel method. The LiCoO2 samples were obtained by sintering the g...LiCoO2 precursors of the cathode material for lithium ion batteries were prepared from lithium hydroxide, basic cobalt carbonate and citric acid by a sol gel method. The LiCoO2 samples were obtained by sintering the gel precursors at different temperatures and for different times. The thermal decomposition behavior of the gel precursors was examined by means of thermo gravimetric analysis and differential thermal analysis using a PCT IA thermal analyzer system. Their structures and morphologies were characterized by powder XRD and SEM techniques. It was found that using citric acid realized that the formation of LiCoO2 crystal can be clearly differentiated to the nucleation and growth processes of the crystals; furthermore, the crystal size can be controlled. Electrochemical tests using the LAND BT1 10 test system showed the electrochemical performance of the material is affected by its integrity and stability.展开更多
Monolayer of octadecylamine（ODA） and salmon sperm DNA or salmon sperm DNA-Cd complex were studied on air-water interface by π-A isotherm. After being co-transferred onto substrates by Langmuir-Blodgett technique, a...Monolayer of octadecylamine（ODA） and salmon sperm DNA or salmon sperm DNA-Cd complex were studied on air-water interface by π-A isotherm. After being co-transferred onto substrates by Langmuir-Blodgett technique, atomic force microscope（AFM） measurements show the DNA molecules are packed into lines in the film, due to the interactions between the ODA and DNA molecules. By exposing the ODA and DNA-Cd complex LB film to H2S, needle-like CdS nanoparticles were formed along the DNA lines as characterized by transmission electron microscope（TEM）. Electron diffraction（ED） image indicates that the so prepared needle-like CdS is a new kind of nanostructured materials.展开更多
文摘Dextran coated magnetic nanocomposites were prepared. A periodate oxidation method was used to further activate the magnetic dextran, forming magnetic polyaldehyde dextran, which could be conjugated to biomolecules, antibodes. The magnetic labeled nano scaled bioconjugates could be well blocked with BSA and exhibit high activity by ELISA and immunochromatographic strip assay.
文摘Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of Li x Mn 2 O 4 were investigated.It was shown that the higher the calcination temperature,the more complete the crystal structure,and the larger the partic le size.Moreover,the influence of c alcination time on the crystal structure was insignificant when it was more than 3h at 700℃.With the increase of x in Li x Mn 2 O 4 in the range of 0.6～1.0,the d 111 and lattice parameter a increased fi rst and then decreased.The electrochemical properties of nano-spinel LiMn 2 O 4 using as cathode material of lithium-ion battery were studied.The low di scharge capacity might be due to the irreversible capacity loss brou ght by the large surface area and latt ice vacancies of the nano-spinel.
文摘The Mengzhuang site lies on a terrace east of Mengzhuang town in southeastern Huixian city, Henan, and occupies an area of 300,000 sq m. It was excavated in 1992-1995, which led to the revelation of remains of the Peiligang, Yangshao, Longshan and Erlitou cultures. Those of the Longshan culture include one city-site, 16 house-foundations, numerous ash-pits and four wells. Among the unearthed Longshan objects are: stone tools - the axe, spade, adze, knife, arrowhead, and chisel; bone implements - the arrowhead, awl, chisel, and spoon ; shell artifacts - the knife and arrowhead ; and pottery-the jar, yah steamer, jia tripod, gui tripod, urn, zeng steamer, basin, vessel stand, cup, vessel cover, bowl, dou stemmed vessel, ring-foot dish, zun-shaped object, li tripod and ding tripod. The whole complex can be divided into two phases, which are dated to 2400--2300 and 2300--2100 BC respectively.
文摘LiCoO2 precursors of the cathode material for lithium ion batteries were prepared from lithium hydroxide, basic cobalt carbonate and citric acid by a sol gel method. The LiCoO2 samples were obtained by sintering the gel precursors at different temperatures and for different times. The thermal decomposition behavior of the gel precursors was examined by means of thermo gravimetric analysis and differential thermal analysis using a PCT IA thermal analyzer system. Their structures and morphologies were characterized by powder XRD and SEM techniques. It was found that using citric acid realized that the formation of LiCoO2 crystal can be clearly differentiated to the nucleation and growth processes of the crystals; furthermore, the crystal size can be controlled. Electrochemical tests using the LAND BT1 10 test system showed the electrochemical performance of the material is affected by its integrity and stability.
文摘Monolayer of octadecylamine（ODA） and salmon sperm DNA or salmon sperm DNA-Cd complex were studied on air-water interface by π-A isotherm. After being co-transferred onto substrates by Langmuir-Blodgett technique, atomic force microscope（AFM） measurements show the DNA molecules are packed into lines in the film, due to the interactions between the ODA and DNA molecules. By exposing the ODA and DNA-Cd complex LB film to H2S, needle-like CdS nanoparticles were formed along the DNA lines as characterized by transmission electron microscope（TEM）. Electron diffraction（ED） image indicates that the so prepared needle-like CdS is a new kind of nanostructured materials.
