In this work, an experimental study was carried out to find the best-operating conditions for the study of the extraction percentage (%E) and the separation factor (SF) of La(III) and Ce(III) complexes. To carry out t...In this work, an experimental study was carried out to find the best-operating conditions for the study of the extraction percentage (%E) and the separation factor (SF) of La(III) and Ce(III) complexes. To carry out this study, a variation of <em>β</em>-diketone concentrations was used, keeping the concentration of tri-octyl phosphine oxide (TOPO) continuous at 0.05 M. The ratio of organic phase to the aqueous phase (O/A) was also studied. The %E and SF were analyzed and compared in the 1,1,1-trifluoro-2, 4-pentanedione (TFA) with TOPO, and 1,1,1,5,5,5-Hexafluoro-2,4-pentanedione (HFAc) with TOPO in Ionic Liquid (IL) and Kerosene. The one-stage extraction efficiency in IL of La(III) and Ce(III) complexes was 42.13% and 77.48% for the TFA-TOPO system and La(III) and Ce(III) complexes were 94.33% and 97.67% for the HFAc-TOPO system. While the SF between Ce(III) and La(III) complexes was 4.91 for TFA-TOPO and 2.64 for HFAc-TOPO. On the other hand, the one-stage extraction efficiency in Kerosene of La(III) and Ce(III) complexes was 27.57% and 63.70% in the TFA-TOPO system. The one-stage extraction efficiency of La(III) and Ce(III) complexes were 99.87% and 99.73% for the HFAc-TOPO system in Kerosene while the SF between Ce(III) and La(III) complexes was 4.62 for TFA-TOPO and 0.49 for HFAc-TOPO. The main conclusion was that using two extractants (<em>β</em>-diketone and TOPO) produced a synergistic effect improving the extraction capacity and SF of La(III) and Ce(III) complexes for both systems in IL and Kerosene.展开更多
Micron sized hexagon- and flower-like nanostructures of lead oxide(α-PbO2) have been synthesized by very simple and cost effective route of anodic oxidation of lead sheet. These structures were easily obtained by t...Micron sized hexagon- and flower-like nanostructures of lead oxide(α-PbO2) have been synthesized by very simple and cost effective route of anodic oxidation of lead sheet. These structures were easily obtained by the simple variation of applied voltage from 2-6 V between the electrodes. Lead sheet was used as an anode and platinum sheet served as a cathode. Anodic oxidation at 2 V resulted in the variable edge sized(1-2 μm) hexagon-like structures in the electrolyte. When the applied potential was increased to 4 V a structure of distorted hexagons consisting of some flower-like structures were obtained. Further increment of potential up to 6 V resulted in flower like structures of α-PbO2 having six petals. The diameter of the flower-like structures was 200-500 nm and the size of a petal was 100-200 nm.展开更多
An analysis of the minimum air temperature behavior was carried out for the southern tip of South America and the western side of the Antarctica Peninsula. Punta Arenas shows an overall annual warming of 0.15°C p...An analysis of the minimum air temperature behavior was carried out for the southern tip of South America and the western side of the Antarctica Peninsula. Punta Arenas shows an overall annual warming of 0.15°C per decade during the 1960-2010 period, although this occurred mainly in the summer and winter seasons. The trend of the air temperature in the western side of the Antarctic Peninsula shows an increase until around 2000, but the warming rate during the last 2001-2010 decade has been less than previous decades;in particular, meteorological stations in King George Island show slight cooling. The lineal annual warming per decade as shown by Bellingshausen, Verndsky/Faraday and Rothera stations are 0.26°C ± 0.75°C, 0.55°C ± 1.26°C and 0.69°C ± 1.31°C;for the respectively, 1969-2010, 1951-2010 and 1978-2010 periods. These rates of warming are slightly lower than those found for the same stations but for the 1969-2000, 1951-2000 and 1978-2000 periods.展开更多
The growth in both production and plantation surface area of blueberries in Chile has been positive, with an estimated surface area of 13,057 hectares (16.9% planting surface) and production in the order of 56,000 ton...The growth in both production and plantation surface area of blueberries in Chile has been positive, with an estimated surface area of 13,057 hectares (16.9% planting surface) and production in the order of 56,000 tons (16.3% mundial production). Of all the different species of blueberry there are several varieties that have advantages with regard to certain conditions;for example, one variety adapts better to the climate of a particular area, while others are better for early or late harvests, they can also be resistant to fungus, bacteria, etc. Companies are very interested in this issue because prior knowledge of such data can bring financial benefits. Blueberries have a significant degree of morphological variation, which enables recognition of different clones with different environmental adaptation characteristics, but it also allows us to discriminate between different levels of fruit quality, which is of commercial interest. However, these morphological characteristics are late in their expression, making it impossible to recognize the clones in the early stage of their development. A more efficient tool to be able to recognize different clones is the use of molecular markers. Of the techniques based the RAPD (randomly amplified polymorphic DNA). They have the advantage that the method has no need for prior knowledge of the DNA sequence. It is of great interest to the private sector to have prior access to information on the types of clone they possess, in order to then be able to differentiate the varieties, but for this it is necessary to obtain a quick and economical technique. In this study, through the use of RAPD-PCR, it is possible to differentiate between different varieties of Vaccinium grown in Chile in order to then optimize blueberry production in terms of time and resources.展开更多
文摘In this work, an experimental study was carried out to find the best-operating conditions for the study of the extraction percentage (%E) and the separation factor (SF) of La(III) and Ce(III) complexes. To carry out this study, a variation of <em>β</em>-diketone concentrations was used, keeping the concentration of tri-octyl phosphine oxide (TOPO) continuous at 0.05 M. The ratio of organic phase to the aqueous phase (O/A) was also studied. The %E and SF were analyzed and compared in the 1,1,1-trifluoro-2, 4-pentanedione (TFA) with TOPO, and 1,1,1,5,5,5-Hexafluoro-2,4-pentanedione (HFAc) with TOPO in Ionic Liquid (IL) and Kerosene. The one-stage extraction efficiency in IL of La(III) and Ce(III) complexes was 42.13% and 77.48% for the TFA-TOPO system and La(III) and Ce(III) complexes were 94.33% and 97.67% for the HFAc-TOPO system. While the SF between Ce(III) and La(III) complexes was 4.91 for TFA-TOPO and 2.64 for HFAc-TOPO. On the other hand, the one-stage extraction efficiency in Kerosene of La(III) and Ce(III) complexes was 27.57% and 63.70% in the TFA-TOPO system. The one-stage extraction efficiency of La(III) and Ce(III) complexes were 99.87% and 99.73% for the HFAc-TOPO system in Kerosene while the SF between Ce(III) and La(III) complexes was 4.62 for TFA-TOPO and 0.49 for HFAc-TOPO. The main conclusion was that using two extractants (<em>β</em>-diketone and TOPO) produced a synergistic effect improving the extraction capacity and SF of La(III) and Ce(III) complexes for both systems in IL and Kerosene.
基金financial support from USACH-Chile, Council of Scientific and Industrial Research (CSIR) and University Grant Commission (UGC) New Delhi, India
文摘Micron sized hexagon- and flower-like nanostructures of lead oxide(α-PbO2) have been synthesized by very simple and cost effective route of anodic oxidation of lead sheet. These structures were easily obtained by the simple variation of applied voltage from 2-6 V between the electrodes. Lead sheet was used as an anode and platinum sheet served as a cathode. Anodic oxidation at 2 V resulted in the variable edge sized(1-2 μm) hexagon-like structures in the electrolyte. When the applied potential was increased to 4 V a structure of distorted hexagons consisting of some flower-like structures were obtained. Further increment of potential up to 6 V resulted in flower like structures of α-PbO2 having six petals. The diameter of the flower-like structures was 200-500 nm and the size of a petal was 100-200 nm.
文摘An analysis of the minimum air temperature behavior was carried out for the southern tip of South America and the western side of the Antarctica Peninsula. Punta Arenas shows an overall annual warming of 0.15°C per decade during the 1960-2010 period, although this occurred mainly in the summer and winter seasons. The trend of the air temperature in the western side of the Antarctic Peninsula shows an increase until around 2000, but the warming rate during the last 2001-2010 decade has been less than previous decades;in particular, meteorological stations in King George Island show slight cooling. The lineal annual warming per decade as shown by Bellingshausen, Verndsky/Faraday and Rothera stations are 0.26°C ± 0.75°C, 0.55°C ± 1.26°C and 0.69°C ± 1.31°C;for the respectively, 1969-2010, 1951-2010 and 1978-2010 periods. These rates of warming are slightly lower than those found for the same stations but for the 1969-2000, 1951-2000 and 1978-2000 periods.
文摘The growth in both production and plantation surface area of blueberries in Chile has been positive, with an estimated surface area of 13,057 hectares (16.9% planting surface) and production in the order of 56,000 tons (16.3% mundial production). Of all the different species of blueberry there are several varieties that have advantages with regard to certain conditions;for example, one variety adapts better to the climate of a particular area, while others are better for early or late harvests, they can also be resistant to fungus, bacteria, etc. Companies are very interested in this issue because prior knowledge of such data can bring financial benefits. Blueberries have a significant degree of morphological variation, which enables recognition of different clones with different environmental adaptation characteristics, but it also allows us to discriminate between different levels of fruit quality, which is of commercial interest. However, these morphological characteristics are late in their expression, making it impossible to recognize the clones in the early stage of their development. A more efficient tool to be able to recognize different clones is the use of molecular markers. Of the techniques based the RAPD (randomly amplified polymorphic DNA). They have the advantage that the method has no need for prior knowledge of the DNA sequence. It is of great interest to the private sector to have prior access to information on the types of clone they possess, in order to then be able to differentiate the varieties, but for this it is necessary to obtain a quick and economical technique. In this study, through the use of RAPD-PCR, it is possible to differentiate between different varieties of Vaccinium grown in Chile in order to then optimize blueberry production in terms of time and resources.