Using direct current-magnetron sputtering,Helium-trapped Ti films with a He/Ar mixture was studied.The relative helium content,helium depth profiles for the Ti films and crystallization capacity were analyzed by Enhan...Using direct current-magnetron sputtering,Helium-trapped Ti films with a He/Ar mixture was studied.The relative helium content,helium depth profiles for the Ti films and crystallization capacity were analyzed by Enhanced Proton Backscattering Spectrometry(EPBS)and X-ray diffraction(XRD).It was found that helium diffusion enhanced as more helium trapping into Ti films,and the He holding ratios were 95.9%,94.9%,93.9%,82.8% when the Ti films with the He/Ti of concentrations of 9.7 at.%,19.5 at.%,19.7 at.%,48.3 at.% were measured again 4 months later,respectively.The diffraction peaks be-came weak and wider,the peak of(002)plane was shifted to smaller diffraction angles and the relevant interplanar spacing d(hkl)increased gradually as more helium trapping into Ti films.The main peak was made trending to the(101)plane by both higher deposition temperature and more helium trapping.展开更多
A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using L...A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using Lawesson's reagent. The X-ray structure of a trimeric analogue(13) revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations(Zn2+, Cd2+, Co2+, Ni2+, Pb2+, and Cu2+) and alkali and alkaline earth metal cations(Li+, Na+, K+, Rb+, Cs+, Ca2+, and Sr2+) demonstrated high efficiency(83.5%–96.4%) and superior selectivity for Cu2+ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order: 6 > 4 > 18 > 15. This is in stark contrast to the oligoamides that only gave much lower extractability(5.9%–16.4%), suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu2+. The complexation behavior of 4, 6, and 8 with Cu2+ was also examined by UV-Vis and NMR techniques.展开更多
基金the China Academy of Engineering Physics(Grant No.2003Z0501)
文摘Using direct current-magnetron sputtering,Helium-trapped Ti films with a He/Ar mixture was studied.The relative helium content,helium depth profiles for the Ti films and crystallization capacity were analyzed by Enhanced Proton Backscattering Spectrometry(EPBS)and X-ray diffraction(XRD).It was found that helium diffusion enhanced as more helium trapping into Ti films,and the He holding ratios were 95.9%,94.9%,93.9%,82.8% when the Ti films with the He/Ti of concentrations of 9.7 at.%,19.5 at.%,19.7 at.%,48.3 at.% were measured again 4 months later,respectively.The diffraction peaks be-came weak and wider,the peak of(002)plane was shifted to smaller diffraction angles and the relevant interplanar spacing d(hkl)increased gradually as more helium trapping into Ti films.The main peak was made trending to the(101)plane by both higher deposition temperature and more helium trapping.
基金supported by the National Natural Science Foundation of China(21172158)the Joint Fund of National Natural Science Foundation of China and the China Academy of Engineering Physics(11076018)+3 种基金the Doctoral Program of the Ministry of Education of China(20130181110023)the National Science Foundation for Fostering Talents in Basic Research of the National Natural Science Foundation of China(J1210004,J1103315)Open Project of State Key Laboratory of Supramolecular Structure and Materials(SKLSSM201408)Open Project of State Key Laboratory of Structural Chemistry(20140013)
文摘A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using Lawesson's reagent. The X-ray structure of a trimeric analogue(13) revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations(Zn2+, Cd2+, Co2+, Ni2+, Pb2+, and Cu2+) and alkali and alkaline earth metal cations(Li+, Na+, K+, Rb+, Cs+, Ca2+, and Sr2+) demonstrated high efficiency(83.5%–96.4%) and superior selectivity for Cu2+ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order: 6 > 4 > 18 > 15. This is in stark contrast to the oligoamides that only gave much lower extractability(5.9%–16.4%), suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu2+. The complexation behavior of 4, 6, and 8 with Cu2+ was also examined by UV-Vis and NMR techniques.
