The peak fields of HT-7U TF/PF coils are designed at 5.8 T and 4.5 T, respectively. The superconducting (SC) NbTi/Cu strands for the coils have a quite low copper fraction (0.58). To increase the ratio of the limiting...The peak fields of HT-7U TF/PF coils are designed at 5.8 T and 4.5 T, respectively. The superconducting (SC) NbTi/Cu strands for the coils have a quite low copper fraction (0.58). To increase the ratio of the limiting current Vs. critical current for the cable in conduit conductor (CICC), the first-stage subcable consists of several copper strands twisted around a SC composite one. The copper strand diameter is different from the SC one. Based on Bottura's CICC design approach we take the product of total copper cross-section and wetted perimeter as one of the key design parameters to meet with stability margin requirement. The product reaches 114 cm3 for 15.5 kA TF CICC at operating temperature of 4.2 K and 139 cm3 for 15 kA PF CICC at 3.8 K to obtain stability margins of 280 and 700 mJ/cm3, respectively.展开更多
Preceding crops as a source of organic matter are important sources of micronutrient and can play an important role in the soil fertility and soil cycling of micronutrients. In addition to the role of the organic matt...Preceding crops as a source of organic matter are important sources of micronutrient and can play an important role in the soil fertility and soil cycling of micronutrients. In addition to the role of the organic matter in increasing the concentration of micronutrients in soil solution, attention should be also paid to the role of the kind and the quantity of the root’s exudates released in response to the incorporation of different plant residues in the rhizosphere. Present research was conducted with the objective of studying the effect of the kind of preceding crops: Trifolium (Trifolium pretense L) and Sorghum (Sorghum bicolor L) on chemical forms of copper (Cu) in solid phases of a calcareous soil in a completely randomized block field experiment with split plot (3 m × 5 m) arrangement, consisting of 3 replications and 3 treatments. After incorporation of the residue, wheat (genotype back cross) was planted. After harvesting the wheat, soil samples were collected from root zone of wheat. Selected soil properties and chemical forms of Cu were determined in the solid phases of the soil samples. Incorporation of plant residues significantly increased the concentration of DTPA-extractable Cu, in the soil. The highest effect was obtained for Trifolium treatment. Incorporation of plant residues decreased the carbonate-bound Cu (Cu-Carb) fraction in the solid phase and increased oxide-bound Cu (Cu-Ox) as compared to the control (fallow treatment). Fraction of organic-bound Cu (Cu-Org) in the soil increased with incorporation of plant residues as compared with the fallow treatment. Trifolium was the most effective in increasing Cu-Org. Cu-Ox and Cu-Residual (Cu-Res) forms showed a significant negative correlation and Cu-Org showed a significant positive correlation with the concentration of DTPA-extractable Cu. Incorporation of Trifolium residues decreased the fraction (%) of Cu-Carb and Cu-Ox (less soluble forms) and consequently increased the fraction (%) of Cu-Org which in turn elevated the concentration of DTPA-extractable Cu. Trifolium was the most effective in increasing the phytoavailability of Cu in soil.展开更多
This paper studies on clinopyroxene, plagioclase of andesitic to dacite rocks of Nochun area to understand the geotectonic and geothermobarometry conditions. Eocene calc-alkaline volcanic rocks are exposed in Nochun t...This paper studies on clinopyroxene, plagioclase of andesitic to dacite rocks of Nochun area to understand the geotectonic and geothermobarometry conditions. Eocene calc-alkaline volcanic rocks are exposed in Nochun that are near the Sarcheshmeh cooper mine. Volcanic rocks consist of andesitic to dacite rocks. Minerals in the volcanic rocks exhibit degrees of disequilibrium features. Plagioclase as dominant mineral in these rocks generally displays oscillatory zoning;sieves or dusty, cores are usually Ca-rich. Petrographic evidence and varying anorthite content (10% to 90%) of plagioclase and temperature estimates of clinopyroxene indicated fractional crystallization condition later than hydrothermal alteration and partial metasomatism occurred. The varying content indicates that the parent’s magma was generated from subalkaline composition and then hydrothermal alteration affected phenocryst minerals and matrix of andesitic to dacite rocks. The equilibration temperatures of clinopyroxene showed (800°C - 1200°C). Thus, in mafic minerals development of sieve textures in plagioclase, reaction rims, zoning and heterogeneity of plagioclase phenocrysts, the resorbed and embayed phenocrysts, unique composition of clinopyroxene phenocrysts;support fractional crystallization at deep reservoir and high pressure condition as an important process in the evolution of these rocks.展开更多
文摘The peak fields of HT-7U TF/PF coils are designed at 5.8 T and 4.5 T, respectively. The superconducting (SC) NbTi/Cu strands for the coils have a quite low copper fraction (0.58). To increase the ratio of the limiting current Vs. critical current for the cable in conduit conductor (CICC), the first-stage subcable consists of several copper strands twisted around a SC composite one. The copper strand diameter is different from the SC one. Based on Bottura's CICC design approach we take the product of total copper cross-section and wetted perimeter as one of the key design parameters to meet with stability margin requirement. The product reaches 114 cm3 for 15.5 kA TF CICC at operating temperature of 4.2 K and 139 cm3 for 15 kA PF CICC at 3.8 K to obtain stability margins of 280 and 700 mJ/cm3, respectively.
文摘Preceding crops as a source of organic matter are important sources of micronutrient and can play an important role in the soil fertility and soil cycling of micronutrients. In addition to the role of the organic matter in increasing the concentration of micronutrients in soil solution, attention should be also paid to the role of the kind and the quantity of the root’s exudates released in response to the incorporation of different plant residues in the rhizosphere. Present research was conducted with the objective of studying the effect of the kind of preceding crops: Trifolium (Trifolium pretense L) and Sorghum (Sorghum bicolor L) on chemical forms of copper (Cu) in solid phases of a calcareous soil in a completely randomized block field experiment with split plot (3 m × 5 m) arrangement, consisting of 3 replications and 3 treatments. After incorporation of the residue, wheat (genotype back cross) was planted. After harvesting the wheat, soil samples were collected from root zone of wheat. Selected soil properties and chemical forms of Cu were determined in the solid phases of the soil samples. Incorporation of plant residues significantly increased the concentration of DTPA-extractable Cu, in the soil. The highest effect was obtained for Trifolium treatment. Incorporation of plant residues decreased the carbonate-bound Cu (Cu-Carb) fraction in the solid phase and increased oxide-bound Cu (Cu-Ox) as compared to the control (fallow treatment). Fraction of organic-bound Cu (Cu-Org) in the soil increased with incorporation of plant residues as compared with the fallow treatment. Trifolium was the most effective in increasing Cu-Org. Cu-Ox and Cu-Residual (Cu-Res) forms showed a significant negative correlation and Cu-Org showed a significant positive correlation with the concentration of DTPA-extractable Cu. Incorporation of Trifolium residues decreased the fraction (%) of Cu-Carb and Cu-Ox (less soluble forms) and consequently increased the fraction (%) of Cu-Org which in turn elevated the concentration of DTPA-extractable Cu. Trifolium was the most effective in increasing the phytoavailability of Cu in soil.
文摘This paper studies on clinopyroxene, plagioclase of andesitic to dacite rocks of Nochun area to understand the geotectonic and geothermobarometry conditions. Eocene calc-alkaline volcanic rocks are exposed in Nochun that are near the Sarcheshmeh cooper mine. Volcanic rocks consist of andesitic to dacite rocks. Minerals in the volcanic rocks exhibit degrees of disequilibrium features. Plagioclase as dominant mineral in these rocks generally displays oscillatory zoning;sieves or dusty, cores are usually Ca-rich. Petrographic evidence and varying anorthite content (10% to 90%) of plagioclase and temperature estimates of clinopyroxene indicated fractional crystallization condition later than hydrothermal alteration and partial metasomatism occurred. The varying content indicates that the parent’s magma was generated from subalkaline composition and then hydrothermal alteration affected phenocryst minerals and matrix of andesitic to dacite rocks. The equilibration temperatures of clinopyroxene showed (800°C - 1200°C). Thus, in mafic minerals development of sieve textures in plagioclase, reaction rims, zoning and heterogeneity of plagioclase phenocrysts, the resorbed and embayed phenocrysts, unique composition of clinopyroxene phenocrysts;support fractional crystallization at deep reservoir and high pressure condition as an important process in the evolution of these rocks.
