1.IntroductionSo far there are few people who studythe relationship between the criticalhydrogen concentration and the stress forhvdrogen induced cracking (CCHIC)quantitatively.Several researchers have cal-culated the...1.IntroductionSo far there are few people who studythe relationship between the criticalhydrogen concentration and the stress forhvdrogen induced cracking (CCHIC)quantitatively.Several researchers have cal-culated the CCHIC of steels under no stressby means of H permeation method,but no展开更多
In the present context, the objective of this study was to synthesize and analyze the content of AA of macadamia protein and the impact of hydrogen ion concentration (pH) on AA composition. The determination of AA mai...In the present context, the objective of this study was to synthesize and analyze the content of AA of macadamia protein and the impact of hydrogen ion concentration (pH) on AA composition. The determination of AA mainly by cation-exchange chromatography was also investigated. Reproducible and reliable techniques for quantification and identification of AA usually require derivatization. However, techniques such as AA analyzer are composed of cation-exchange chromatography and other components can sideline the derivatization with significant accuracy. The present analysis revealed a higher concentration of essential amino acids especially acidic AA, Glu and Asp and basic AA, Arg than other AA in macadamia protein. The study constitutes first report of use of bubble chart for evaluation of AA and explaination of AAS. The results may elaborate that the degradation of AA of macadamia protein for extraction of pH 11 is caused by the impact of pH. Moreover, the nutritional values of AA present in macadamia protein could change for the better by adjusting pH of extraction.展开更多
The China Spallation Neutron Source（CSNS） is driven by protons whose energies are about 1.6 GeV.At such high energies, the spallation neutrons lead to the formation of large amounts of helium, hydrogen and new heavi...The China Spallation Neutron Source（CSNS） is driven by protons whose energies are about 1.6 GeV.At such high energies, the spallation neutrons lead to the formation of large amounts of helium, hydrogen and new heavier species in the form of transmutation products. These hydrogen, helium and transmutation products have a critical effect on the mechanical properties on the one hand and exacerbate the displacement radiation damage on the other hand. In this paper, the background hydrogen/helium concentrations and the maximum hydrogen/helium concentrations near cracks in a tungsten target for CSNS have been calculated at temperatures of 100 and 300 by applying a theoretical model. For the CSNS tungsten target plate, we find the maximum hydrogen concentration near the tips of cracks ranges from 3.0×10^（-2）–2×10^（-1）, which exceeds the hydrogen background concentration by 1.2–1.8 times; the maximum helium concentration near the tips of cracks ranges from 3.0×10^（-4）- 1.2×10^（-3）, which exceeds the helium background concentration by 2- 4 times; the maximum hydrogen/helium concentration increases with the increase of the transfer length across the surfaces of the target and it decreases with the increase of temperature.展开更多
Continuous measurements of pH precipitation falling from cumulus clouds in semi-arid region (Colorado,USA),and in wet temperate zone(Bologna,Italy)were made.In Colorado the pH was constant at 7.3 for a period of time,...Continuous measurements of pH precipitation falling from cumulus clouds in semi-arid region (Colorado,USA),and in wet temperate zone(Bologna,Italy)were made.In Colorado the pH was constant at 7.3 for a period of time,and later changed to 7.0 and remained constant at this value during the remainder of the storm.In Italy the pH fluctuated continuously between the approximate values of 5.7 and 6.4 during the storm.The changes in hydrogen ion concentration reflect the chemical composition of cloud condensation nuclei and of scavenged aerosol particles and gases presented in the region.展开更多
The flotability and mechanism of tantalite-niobite minerals which have different contents of Ta, Nb, Fe Mn using styrenephosphonic acid (SPA) were investigated. The optimum pH value in pulp is less than 5, flotability...The flotability and mechanism of tantalite-niobite minerals which have different contents of Ta, Nb, Fe Mn using styrenephosphonic acid (SPA) were investigated. The optimum pH value in pulp is less than 5, flotability varies with the different contents of mineral, and flotability of minerals with higher Nb2O5 content is better than that with higher Ta2O5 content. In wide range of pH in solution, the Fe, Mn on the surface are the main active species for flotation. Research using Auger electron spectroscopy, infrared spectroscopy and ultraviolet spectroscopy for determining surface conditions has been done. SPA interacts with Fe, Mn ions on the surface by a chemical bond force. On the outer layer of the collector, which is a non-uniform multilayer, adsorption of SPA on surface is both chemico-adsorption and physico-adsorption, but chemico-adsorption is dominant.展开更多
文摘1.IntroductionSo far there are few people who studythe relationship between the criticalhydrogen concentration and the stress forhvdrogen induced cracking (CCHIC)quantitatively.Several researchers have cal-culated the CCHIC of steels under no stressby means of H permeation method,but no
文摘In the present context, the objective of this study was to synthesize and analyze the content of AA of macadamia protein and the impact of hydrogen ion concentration (pH) on AA composition. The determination of AA mainly by cation-exchange chromatography was also investigated. Reproducible and reliable techniques for quantification and identification of AA usually require derivatization. However, techniques such as AA analyzer are composed of cation-exchange chromatography and other components can sideline the derivatization with significant accuracy. The present analysis revealed a higher concentration of essential amino acids especially acidic AA, Glu and Asp and basic AA, Arg than other AA in macadamia protein. The study constitutes first report of use of bubble chart for evaluation of AA and explaination of AAS. The results may elaborate that the degradation of AA of macadamia protein for extraction of pH 11 is caused by the impact of pH. Moreover, the nutritional values of AA present in macadamia protein could change for the better by adjusting pH of extraction.
基金Supported by National Science Foundation of China(51371195,11174358)
文摘The China Spallation Neutron Source（CSNS） is driven by protons whose energies are about 1.6 GeV.At such high energies, the spallation neutrons lead to the formation of large amounts of helium, hydrogen and new heavier species in the form of transmutation products. These hydrogen, helium and transmutation products have a critical effect on the mechanical properties on the one hand and exacerbate the displacement radiation damage on the other hand. In this paper, the background hydrogen/helium concentrations and the maximum hydrogen/helium concentrations near cracks in a tungsten target for CSNS have been calculated at temperatures of 100 and 300 by applying a theoretical model. For the CSNS tungsten target plate, we find the maximum hydrogen concentration near the tips of cracks ranges from 3.0×10^（-2）–2×10^（-1）, which exceeds the hydrogen background concentration by 1.2–1.8 times; the maximum helium concentration near the tips of cracks ranges from 3.0×10^（-4）- 1.2×10^（-3）, which exceeds the helium background concentration by 2- 4 times; the maximum hydrogen/helium concentration increases with the increase of the transfer length across the surfaces of the target and it decreases with the increase of temperature.
文摘Continuous measurements of pH precipitation falling from cumulus clouds in semi-arid region (Colorado,USA),and in wet temperate zone(Bologna,Italy)were made.In Colorado the pH was constant at 7.3 for a period of time,and later changed to 7.0 and remained constant at this value during the remainder of the storm.In Italy the pH fluctuated continuously between the approximate values of 5.7 and 6.4 during the storm.The changes in hydrogen ion concentration reflect the chemical composition of cloud condensation nuclei and of scavenged aerosol particles and gases presented in the region.
文摘The flotability and mechanism of tantalite-niobite minerals which have different contents of Ta, Nb, Fe Mn using styrenephosphonic acid (SPA) were investigated. The optimum pH value in pulp is less than 5, flotability varies with the different contents of mineral, and flotability of minerals with higher Nb2O5 content is better than that with higher Ta2O5 content. In wide range of pH in solution, the Fe, Mn on the surface are the main active species for flotation. Research using Auger electron spectroscopy, infrared spectroscopy and ultraviolet spectroscopy for determining surface conditions has been done. SPA interacts with Fe, Mn ions on the surface by a chemical bond force. On the outer layer of the collector, which is a non-uniform multilayer, adsorption of SPA on surface is both chemico-adsorption and physico-adsorption, but chemico-adsorption is dominant.
