The molecular structure of the title compound, ph3AsC (COCH3 )Seph, has been determined by X--ray diffraction. Crystallographic data: Mr= 517. 36'monoclinic, P21,/c, a=11. 499(4), b=9. 619(4), c=20. 919(7),A, β=9...The molecular structure of the title compound, ph3AsC (COCH3 )Seph, has been determined by X--ray diffraction. Crystallographic data: Mr= 517. 36'monoclinic, P21,/c, a=11. 499(4), b=9. 619(4), c=20. 919(7),A, β=98. 82(2)°,V= 2286(l) A 3, Z=4, Dc= 1. 509 g/cm3, μ(MoKa) = 3. 073 cm-1, F(000) = 1040and the final R=0. 042, Rw= 0. 041. In the molecule, the geometry of arsenic atom isa distorted tetrahedron, the bonds of Se--C (3) and As--C(31 ) have striking characteristics of double bond, the delocalization of electronic density occurs to be restrictedfrom O(1 ) to Se atoms.展开更多
This paper presents a new idea for intensifying protective and stretch recovery properties of micro porous polytetrafluorethylene and hydrophilic polyurethane (PTFE/PU) layered membrane through a co-stretching process...This paper presents a new idea for intensifying protective and stretch recovery properties of micro porous polytetrafluorethylene and hydrophilic polyurethane (PTFE/PU) layered membrane through a co-stretching process. The structure and properties of co-stretching PTFE/PU layered membrane and coated PTFE/PU layered membrane by means of directly coating the PU on the PTFE membrane were investigated using Electron Microscope, Universal Materials Testing Machine, and the water vapor permeability (WVP) was measured according to absorption method of water vapor of GB/T 12704-91. Contrasted to PU coating process, the PU membrane on the co-stretching PTFE/PU membrane is nonporous because of heat treatment process, which can prevent the SARS virus from permeating the Co-stretching PTFE/PU membrane. The stretch and recovery properties of the Co-stretching PTFE/PU membrane is at least 66% after being stretched to 50% of its original length in transverse directions and that of the coated PTFE/PU membrane is 52%. The WVP of the Co-stretching PTFE/PU membrane is 13 523 g/24 h·m^2. The results suggest that when Co-stretching PTFE/PU membrane is laminated to a stretchable fabric, the fabric would have excellent stretch and recovery properties while waterproof and being permeable to water vapor. So, the Co-stretching PTFE/PU membrane laminated fabric will be a comfortable protective clothing material.展开更多
The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in eith...The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.展开更多
文摘The molecular structure of the title compound, ph3AsC (COCH3 )Seph, has been determined by X--ray diffraction. Crystallographic data: Mr= 517. 36'monoclinic, P21,/c, a=11. 499(4), b=9. 619(4), c=20. 919(7),A, β=98. 82(2)°,V= 2286(l) A 3, Z=4, Dc= 1. 509 g/cm3, μ(MoKa) = 3. 073 cm-1, F(000) = 1040and the final R=0. 042, Rw= 0. 041. In the molecule, the geometry of arsenic atom isa distorted tetrahedron, the bonds of Se--C (3) and As--C(31 ) have striking characteristics of double bond, the delocalization of electronic density occurs to be restrictedfrom O(1 ) to Se atoms.
基金Supported by the Ph. D.Innovation Foundation of Donghua University (101 06 0019064)
文摘This paper presents a new idea for intensifying protective and stretch recovery properties of micro porous polytetrafluorethylene and hydrophilic polyurethane (PTFE/PU) layered membrane through a co-stretching process. The structure and properties of co-stretching PTFE/PU layered membrane and coated PTFE/PU layered membrane by means of directly coating the PU on the PTFE membrane were investigated using Electron Microscope, Universal Materials Testing Machine, and the water vapor permeability (WVP) was measured according to absorption method of water vapor of GB/T 12704-91. Contrasted to PU coating process, the PU membrane on the co-stretching PTFE/PU membrane is nonporous because of heat treatment process, which can prevent the SARS virus from permeating the Co-stretching PTFE/PU membrane. The stretch and recovery properties of the Co-stretching PTFE/PU membrane is at least 66% after being stretched to 50% of its original length in transverse directions and that of the coated PTFE/PU membrane is 52%. The WVP of the Co-stretching PTFE/PU membrane is 13 523 g/24 h·m^2. The results suggest that when Co-stretching PTFE/PU membrane is laminated to a stretchable fabric, the fabric would have excellent stretch and recovery properties while waterproof and being permeable to water vapor. So, the Co-stretching PTFE/PU membrane laminated fabric will be a comfortable protective clothing material.
文摘The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.
