This paper presents an experimental study including visualization on a flat plate closed loop pulsating heat pipes.It consists of a total of 40 channels with square cross section(2 mm×2 mm,165 mm long) machined d...This paper presents an experimental study including visualization on a flat plate closed loop pulsating heat pipes.It consists of a total of 40 channels with square cross section(2 mm×2 mm,165 mm long) machined directly on an aluminum plate(180 mm×120 mm×3 mm) covered by a transparent plate.The working fluid employed is ethanol.As a result,various flow patterns and their transitions are observed and found to be related to the fluid fill ratio,input heat load and the device orientation.Also the operational characteristics and working mechanism are discussed.展开更多
We studied the dielectric properties of organosilicon-containing helical cyclopolymer PbMA which consists of PMMA main chains and tetramethyldisiloxane side rings. PbMA formed films with excellent uniformity through s...We studied the dielectric properties of organosilicon-containing helical cyclopolymer PbMA which consists of PMMA main chains and tetramethyldisiloxane side rings. PbMA formed films with excellent uniformity through spin-coating onto highly n-doped silicon （n-Si） wafers for constructing devices of dielectric measurements, on which the dielectric properties and I-V characteristics of PbMA were studied. PbMA has a much lower dielectric constant （lower than 2.6） in the frequency range of 10-105 Hz, and better thermal stability than PMMA does. I-V data showed that the metal/PbMA/n-Si devices have different conducting directions, depending on whether Au or Al deposited over PbMA layers.展开更多
A new rare earth complex Eu（III） （TTA）2（MA）2Phen · H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal s...A new rare earth complex Eu（III） （TTA）2（MA）2Phen · H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal stability of Eu（III） （TTA）2（MA）2Phen · H2O were used to modify resin. The copolymer containing europium was prepared by copolymerization of Eu（III） and styrene/α- methylacrylic acid, and characterized by FTIR and fluorescence spectra. The fluorescence spectra showed that the copolymer was a sort of materials with good fluorescence property, and the higher fluorescence intensity came from the higher europium content.展开更多
A novel environmental friendly catalyst, H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H4SiW12O4...A novel environmental friendly catalyst, H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H4SiW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesis of n-butyl methacrylate and Keggin structure ofH4SiW12O40 kept unchanged after impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）： n（n-butyl alcohol）, catalyst dosage, cyclohexane （water-stripped reagent） and reaction time on the yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.5, mass ratio of catalyst used to the reactant is 1.5%, cyclohexane is 10 mL and reaction time is 1.5h. Under these conditions, the yield of n-butyl methacrylate can reach 73.2%.展开更多
Poly （methyl methacrylate） scrap was applied to prepare the impact modification of r-PMMA/PMMA-blend-PU/Ecoflex sheet by casting process. The Ecoflex and polyurethane were used as biodegradable polymer and impact mo...Poly （methyl methacrylate） scrap was applied to prepare the impact modification of r-PMMA/PMMA-blend-PU/Ecoflex sheet by casting process. The Ecoflex and polyurethane were used as biodegradable polymer and impact modified respectively. This research was ascertained tile way to reduce the processing cost of PMMA sheet and the industrial waste by recycled PMMA scrap into the production process. The r-PMMA/PMMA-blend-PU/Ecoflex sheet was studied potential degradation by landfills for six months. After degradation the percentage of weight loss of specimens was increasing depend on amount of Ecoflex content and degradation period. While, the surface morphology of r-PMMA/PMMA-blend-PU/Ecoflex sheet after six months was damaged and demonstrated that Ecoflex had an effect on PMMA-blend-PU sheet in potential biodegradation. The mechanical and physical properties of r-PMMA/PMMA-blend-PU/Ecoflex sheet were described. Finally, the impact strength of r-PMMA/PMMA-blend-PU/Ecoflex sheet from this research, it is possible to use r-PMMA and Ecoflex in the acrylic casting sheet product.展开更多
When exposed to biotic or abiotic stress conditions, plants produce ethylene from its immediate precursor 1-aminocyclopropane-1- carboxylate （ACC）, leading to retarded root growth and senescence. Many plant growth-p...When exposed to biotic or abiotic stress conditions, plants produce ethylene from its immediate precursor 1-aminocyclopropane-1- carboxylate （ACC）, leading to retarded root growth and senescence. Many plant growth-promoting rhizobacteria contain the enzyme ACC deaminase and this enzyme can cleave ACC to form a-ketobutyrate and ammonium, thereby lowering levels of ethylene. The aim of this study was to isolate and characterize ACC deaminase-producing bacteria from the rhizosphere of salt-stressed canola （Brassica napus L.）. Out of 105 random bacterial isolates, 15 were able to utilize ACC as the sole source of nitrogen. These 15 isolates were also positive for indole acetic acid （IAA） production. Phylogenetic analysis based on partial 16S rDNA sequences showed that all isolates belonged to fluorescent Pseudomonas spp. In the canola rhizosphere investigated in this study, Pseudomonas fluorescens was the dominant ACC deaminase-producing species. Cluster analysis based on BOX-AIR-based repetitive extragenic palindromic-polymerase chain reaction （BOX-PCR） patterns suggested a high degree of genetic variability in ACC deaminase-producing P. fluorescens strains. The presence of indigenous ACC-degrading bacteria in the rhizosphere of canola grown in saline soils indicates that these bacteria may contribute to salinity tolerance.展开更多
基金the Ger man National Science Foundation (GR-412/33-2)Shanghai Leading Academic Discipline Project (No.B604)
文摘This paper presents an experimental study including visualization on a flat plate closed loop pulsating heat pipes.It consists of a total of 40 channels with square cross section(2 mm×2 mm,165 mm long) machined directly on an aluminum plate(180 mm×120 mm×3 mm) covered by a transparent plate.The working fluid employed is ethanol.As a result,various flow patterns and their transitions are observed and found to be related to the fluid fill ratio,input heat load and the device orientation.Also the operational characteristics and working mechanism are discussed.
基金This work was supported by the National Natural Science Foundation of China （No.51673181）.
文摘We studied the dielectric properties of organosilicon-containing helical cyclopolymer PbMA which consists of PMMA main chains and tetramethyldisiloxane side rings. PbMA formed films with excellent uniformity through spin-coating onto highly n-doped silicon （n-Si） wafers for constructing devices of dielectric measurements, on which the dielectric properties and I-V characteristics of PbMA were studied. PbMA has a much lower dielectric constant （lower than 2.6） in the frequency range of 10-105 Hz, and better thermal stability than PMMA does. I-V data showed that the metal/PbMA/n-Si devices have different conducting directions, depending on whether Au or Al deposited over PbMA layers.
基金Research Topics of Shanghai Scientific Committee,China (No.065458025)
文摘A new rare earth complex Eu（III） （TTA）2（MA）2Phen · H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal stability of Eu（III） （TTA）2（MA）2Phen · H2O were used to modify resin. The copolymer containing europium was prepared by copolymerization of Eu（III） and styrene/α- methylacrylic acid, and characterized by FTIR and fluorescence spectra. The fluorescence spectra showed that the copolymer was a sort of materials with good fluorescence property, and the higher fluorescence intensity came from the higher europium content.
基金Acknowledgment： This work was financially supported by the Natural Science Foundation of Hubei Province, China （No. 2005ABA053） and Hubei Normal University.
文摘A novel environmental friendly catalyst, H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of n-butyl methacrylate catalyzed by H4SiW12O40/MCM-48 was studied with methacrylic acid and n-butyl alcohol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesis of n-butyl methacrylate and Keggin structure ofH4SiW12O40 kept unchanged after impregnated on surface of the molecular sieve support. Effects of n（methacrylic acid）： n（n-butyl alcohol）, catalyst dosage, cyclohexane （water-stripped reagent） and reaction time on the yields of the product were investigated. The optimum conditions have been found, that is, molar ratio of acid to alcohol is 1：1.5, mass ratio of catalyst used to the reactant is 1.5%, cyclohexane is 10 mL and reaction time is 1.5h. Under these conditions, the yield of n-butyl methacrylate can reach 73.2%.
文摘Poly （methyl methacrylate） scrap was applied to prepare the impact modification of r-PMMA/PMMA-blend-PU/Ecoflex sheet by casting process. The Ecoflex and polyurethane were used as biodegradable polymer and impact modified respectively. This research was ascertained tile way to reduce the processing cost of PMMA sheet and the industrial waste by recycled PMMA scrap into the production process. The r-PMMA/PMMA-blend-PU/Ecoflex sheet was studied potential degradation by landfills for six months. After degradation the percentage of weight loss of specimens was increasing depend on amount of Ecoflex content and degradation period. While, the surface morphology of r-PMMA/PMMA-blend-PU/Ecoflex sheet after six months was damaged and demonstrated that Ecoflex had an effect on PMMA-blend-PU sheet in potential biodegradation. The mechanical and physical properties of r-PMMA/PMMA-blend-PU/Ecoflex sheet were described. Finally, the impact strength of r-PMMA/PMMA-blend-PU/Ecoflex sheet from this research, it is possible to use r-PMMA and Ecoflex in the acrylic casting sheet product.
文摘When exposed to biotic or abiotic stress conditions, plants produce ethylene from its immediate precursor 1-aminocyclopropane-1- carboxylate （ACC）, leading to retarded root growth and senescence. Many plant growth-promoting rhizobacteria contain the enzyme ACC deaminase and this enzyme can cleave ACC to form a-ketobutyrate and ammonium, thereby lowering levels of ethylene. The aim of this study was to isolate and characterize ACC deaminase-producing bacteria from the rhizosphere of salt-stressed canola （Brassica napus L.）. Out of 105 random bacterial isolates, 15 were able to utilize ACC as the sole source of nitrogen. These 15 isolates were also positive for indole acetic acid （IAA） production. Phylogenetic analysis based on partial 16S rDNA sequences showed that all isolates belonged to fluorescent Pseudomonas spp. In the canola rhizosphere investigated in this study, Pseudomonas fluorescens was the dominant ACC deaminase-producing species. Cluster analysis based on BOX-AIR-based repetitive extragenic palindromic-polymerase chain reaction （BOX-PCR） patterns suggested a high degree of genetic variability in ACC deaminase-producing P. fluorescens strains. The presence of indigenous ACC-degrading bacteria in the rhizosphere of canola grown in saline soils indicates that these bacteria may contribute to salinity tolerance.
