In this manuscript, a series of catalyst SG n-[VVO2-PAMAM-MSA] (SG silica gel, PAMAM polyamidoamine, MSA 5-methyl salicylaldehyde, n=0, 1, 2, 3) was prepared and their structures were fully characterized by Fourier tr...In this manuscript, a series of catalyst SG n-[VVO2-PAMAM-MSA] (SG silica gel, PAMAM polyamidoamine, MSA 5-methyl salicylaldehyde, n=0, 1, 2, 3) was prepared and their structures were fully characterized by Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and inductive coupled plasma emission spectrometer (ICP) etc. XPS revealed that the metal V and SG n-PAMAM-MSA combined more closely after the formation of Schiff base derivatives. Their catalytic activities for oxidation of dibenzothiophene were evaluated using tert-butyl hydroperoxide as oxidant. The results showed that the catalyst SG 2.0-[VVO2-PAMAM-MSA] presented good catalytic activity and recycling time. Meanwhile, the optimal condition for the catalytic oxidation of SG 2.0-[VVO2-PAMAM-MSA] was also investigated, which showed that when the oxidation temperature was 90 °C, time was 60 min, the O/S was 3:1, and the mass content of catalyst was 1%, the rate of desulfurization could reach 85.2%. Moreover, the catalyst can be recycled several times without significant decline in catalytic activity.展开更多
A novel method of initiating nuclear fusion reactions in a full plasma environment was suggested, and a proof-of-concept experiment was carried out with the D ＋D → n＋3He reaction. In this new approach, two plasma j...A novel method of initiating nuclear fusion reactions in a full plasma environment was suggested, and a proof-of-concept experiment was carried out with the D ＋D → n＋3He reaction. In this new approach, two plasma jets generated by high-intensity lasers collide headon-head. The center-of-mass energy of the nuclei increases accordingly, and therefore, reaction products can be significantly enhanced, especially in the sub-Coulomb barrier ranges. As a result of the fusion reaction, up to - 7.6 ×105 neutrons had been observed. This new type of ＂plasma collider＂ could provide an innovative tool to study nuclear reactions under astrophysical conditions.展开更多
This paper describes a new method to design a laser mirror with high reflectivity, wide reflection bandwidth and high laser- induced damage threshold. The mirror is constructed by three materials of HfO/TiO2/SiO2 base...This paper describes a new method to design a laser mirror with high reflectivity, wide reflection bandwidth and high laser- induced damage threshold. The mirror is constructed by three materials of HfO/TiO2/SiO2 based on electric field and temperature field distribution characteristics of all-dielectric laser high reflector. TiO/SiO2 stacks act as the high reflector （HR） and broaden the reflection bandwidth, while HfO2/SiO2 stacks are used for increasing the laser resistance. The HfO/ TiO/SiO2 laser mirror with 34 layers is fabricated by a novel remote plasma sputtering deposition. The damage threshold of zero damage probability for the new mirror is up to 39.6 J/cm^2 （1064 nm, 12 ns）. The possible laser damage mechanism of the mirror is discussed.展开更多
The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a magnetized dusty plasma region and a vacuum is derived by using specular reflection boundary con...The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a magnetized dusty plasma region and a vacuum is derived by using specular reflection boundary conditions both in classical and quantum regimes. The frequency limit ω ≤ωei ≤ ωce is considered and the dispersion relation for the Dust-Lower-Hybrid Surface Waves （DLHSW＇s） is derived for both classical and quantum plasma half-space and analyzed numerically. It is shown that the wave behavior changes as the quantum nature of the problem is considered.展开更多
The decomposition of Cull nanoparticles in aqueous solution has been successfully developed as a novel method for the preparation of Cu2O nanoparticles. In particular, we found that the decomposition of Cull nanoparti...The decomposition of Cull nanoparticles in aqueous solution has been successfully developed as a novel method for the preparation of Cu2O nanoparticles. In particular, we found that the decomposition of Cull nanoparticles in aqueous solution could be catalyzed by Au colloids, forming CU2O-Au nanocomposites. The composition and structure of the resulting Cu2O-Au nanocomposites have been characterized in detail by inductively coupled plasma atomic emission spectroscopy, powder X-ray diffraction, N2 adsorption-desorption isotherms, infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Their visible-light-driven photocatalytic activity toward various dye molecules has also been investigated. Depending on the Au：Cu ratio, Cu20-Au nanocomposites exhibit different novel nanostructures including a beautiful flower-like nanostructure that consists of polycrystalline Cu2O, amorphous Cu2O and Au colloids. We propose that the rapidly-generated bubbles of H2 during the course of the catalytic decomposition reaction drive the simultaneously-formed Cu2O to form amorphous curved thin foils and might also act as a template to assemble curved thin foils of amorphous Cu2O, polycrystalline Cu2O and Au colloids into uniform nanostructures. A Cu2O-Au nanocomposite with a Cu：Au ratio of 40 exhibits remarkable chemisorption capacity and visible-light-driven photocatalytic activity towards methyl orange and acid orange 7 and is a promising chemisorption-photocatalysis integrated catalyst. The catalytic decomposition of the metal hydride might open up a new approach for the fabrication of other metal/metal oxide nanocomposites with novel nanostructures and properties.展开更多
基金Supported by the National Natural Science Foundation of China （20901063） the Natural Science Foundation of Hubei Province （2011CDB221）
文摘In this manuscript, a series of catalyst SG n-[VVO2-PAMAM-MSA] (SG silica gel, PAMAM polyamidoamine, MSA 5-methyl salicylaldehyde, n=0, 1, 2, 3) was prepared and their structures were fully characterized by Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and inductive coupled plasma emission spectrometer (ICP) etc. XPS revealed that the metal V and SG n-PAMAM-MSA combined more closely after the formation of Schiff base derivatives. Their catalytic activities for oxidation of dibenzothiophene were evaluated using tert-butyl hydroperoxide as oxidant. The results showed that the catalyst SG 2.0-[VVO2-PAMAM-MSA] presented good catalytic activity and recycling time. Meanwhile, the optimal condition for the catalytic oxidation of SG 2.0-[VVO2-PAMAM-MSA] was also investigated, which showed that when the oxidation temperature was 90 °C, time was 60 min, the O/S was 3:1, and the mass content of catalyst was 1%, the rate of desulfurization could reach 85.2%. Moreover, the catalyst can be recycled several times without significant decline in catalytic activity.
基金supported by the National Basic Research Program of China(2013CBA01501 and2013CB834401)the National Natural Science Foundation of China(11135012 and 11135005)+1 种基金the Doctoral Fund of Ministry of Education of China(20120073110065)Shanghai Municipal Science and Technology Commission(11DZ2260700)for the supports
文摘A novel method of initiating nuclear fusion reactions in a full plasma environment was suggested, and a proof-of-concept experiment was carried out with the D ＋D → n＋3He reaction. In this new approach, two plasma jets generated by high-intensity lasers collide headon-head. The center-of-mass energy of the nuclei increases accordingly, and therefore, reaction products can be significantly enhanced, especially in the sub-Coulomb barrier ranges. As a result of the fusion reaction, up to - 7.6 ×105 neutrons had been observed. This new type of ＂plasma collider＂ could provide an innovative tool to study nuclear reactions under astrophysical conditions.
基金supported by the National Natural Science Foundation of China (No.50802080)the Natural Science Foundation of Fujian Province of China (No.2010J01349)
文摘This paper describes a new method to design a laser mirror with high reflectivity, wide reflection bandwidth and high laser- induced damage threshold. The mirror is constructed by three materials of HfO/TiO2/SiO2 based on electric field and temperature field distribution characteristics of all-dielectric laser high reflector. TiO/SiO2 stacks act as the high reflector （HR） and broaden the reflection bandwidth, while HfO2/SiO2 stacks are used for increasing the laser resistance. The HfO/ TiO/SiO2 laser mirror with 34 layers is fabricated by a novel remote plasma sputtering deposition. The damage threshold of zero damage probability for the new mirror is up to 39.6 J/cm^2 （1064 nm, 12 ns）. The possible laser damage mechanism of the mirror is discussed.
基金financial support during the course of this work through indigenous fellowship scheme PIN 041601217P-147the Higher Education Commission (HEC) Grant No. 20-1886/R&D/10
文摘The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a magnetized dusty plasma region and a vacuum is derived by using specular reflection boundary conditions both in classical and quantum regimes. The frequency limit ω ≤ωei ≤ ωce is considered and the dispersion relation for the Dust-Lower-Hybrid Surface Waves （DLHSW＇s） is derived for both classical and quantum plasma half-space and analyzed numerically. It is shown that the wave behavior changes as the quantum nature of the problem is considered.
基金This work was financially supported by the National Natural Science Foundation of China （grant No. 20773113）, the Solar Energy Project of the Chinese Academy of Sciences, the National Basic Research Program of China （No. 2010CB923302）, MOE program for PCSIRT （IRT0756）, the Fundamental Research Funds for the Central Universities （No. WK2060030005）, and the MPG-CAS partner group program.
文摘The decomposition of Cull nanoparticles in aqueous solution has been successfully developed as a novel method for the preparation of Cu2O nanoparticles. In particular, we found that the decomposition of Cull nanoparticles in aqueous solution could be catalyzed by Au colloids, forming CU2O-Au nanocomposites. The composition and structure of the resulting Cu2O-Au nanocomposites have been characterized in detail by inductively coupled plasma atomic emission spectroscopy, powder X-ray diffraction, N2 adsorption-desorption isotherms, infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Their visible-light-driven photocatalytic activity toward various dye molecules has also been investigated. Depending on the Au：Cu ratio, Cu20-Au nanocomposites exhibit different novel nanostructures including a beautiful flower-like nanostructure that consists of polycrystalline Cu2O, amorphous Cu2O and Au colloids. We propose that the rapidly-generated bubbles of H2 during the course of the catalytic decomposition reaction drive the simultaneously-formed Cu2O to form amorphous curved thin foils and might also act as a template to assemble curved thin foils of amorphous Cu2O, polycrystalline Cu2O and Au colloids into uniform nanostructures. A Cu2O-Au nanocomposite with a Cu：Au ratio of 40 exhibits remarkable chemisorption capacity and visible-light-driven photocatalytic activity towards methyl orange and acid orange 7 and is a promising chemisorption-photocatalysis integrated catalyst. The catalytic decomposition of the metal hydride might open up a new approach for the fabrication of other metal/metal oxide nanocomposites with novel nanostructures and properties.
