Abundances of lithium, sodium, and potassium in Vega
نویسنده
چکیده
Vega’s photospheric abundances of Li, Na, and K were determined by using considerably weak lines measured on the very high-S/N spectrum, while the non-LTE correction and the gravity-darkening correction were adequately taken into account. It was confirmed that these alkali elements are mildly underabundant ([Li/H] ≃ −0.6, [Na/H] ≃ −0.3, and [K/H] ≃ −0.2) compared to the solar system values, as generally seen also in other metals. Since the tendency of Li being more deficient than Na and K is qualitatively similar to what is seen in typical interstellar cloud, the process of interstellar gas accretion may be related with the abundance anomaly of Vega, as suspected in the case of λ Boo stars.
منابع مشابه
The effect of titanium dioxide and molybdenum oxide on the properties of sodium potassium niobate piezoceramic
Sodium potassium niobate piezoceramics are considered as lead-free piezoelectric due to their good properties. In this study, the effect of titanium dioxide and molybdenum oxide as dopant on the densification behavior, piezoelectric and dielectric properties of lithium doped sodium potassium niobate ((K0.5Na0.5)0.94Li0.06NbO3, KNNL) was investigated. For this purpose, (K0.5Na0.5)0.94Li0.06Nb0.9...
متن کاملشناسایی انواع کانیهای تبخیری زیر پهنه های کویر سیاه کوه استان یزد
the Siahkuh playa is one of the greatest deserts in Yu.d province and is located in the north-north eastern of Ardakan city. In playa regions, different sub-environments with different mineral potentials can be recognized. In Siahkuh playa, various evaporite minerals such as gypsum in different form (sugery, nodular and euhedral crystals), halite (fibrous, cylindrical, hopper-shaped crysta...
متن کاملEvaluation of Salt, Sodium, and Potassium Intake Through Bread Consumption in Chaharmahal and Bakhtiari Province
Background and aims: Bread is considered as one of the important sources of sodium in the Iraniandiet and salt is the main source of sodium, which is used to produce bread. The assessment of dietaryintake is a reliable method that shows nutritional problems in the community. Therefore, the purposeof this study was to evaluate the intake of salt, sodium, and potassium through b...
متن کاملThe Influence of Potassium- and Sodium-Free Solutions on Sodium Efflux from Squid Giant Axons
The sensitivity of sodium efflux to the removal of potassium ions from the external solution and the change in sodium efflux occurring when sodium ions are also removed were observed to be related. When Tris was used to replace external sodium ions, increases in sodium efflux were always observed whether the sensitivity of sodium efflux to external potassium ions was weak or strong. Greater per...
متن کاملDetermination of Potassium Sorbate and Sodium Benzoate in "Doogh" by HPLC and Comparison with Spectrophotometry
There are various methods for the analysis of Potassium Sorbate and Sodium Benzoate in food products, but a rapid and reliable method for identification of these preservatives in Doogh (an Iranian traditional dairy drink) is a procedure, in which high performance liquid chromatography (HPLC) utilized and followed by UV diode array detection of the two preservatives. The aim of this case study w...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008