China
Africa
Explore chapters and articles related to this topic
39K
Published in Guillaume Madelin, X-Nuclei Magnetic Resonance Imaging, 2022
Potassium (symbol: K, from the Latin kalium) is the 19th element of the periodic table. It is a member of the alkali metal group (group 1) with a 4s1 electronic configuration, and therefore has a single electron on its outermost shell, which it can easily lose or donate to form a cation, K+. Of the 24 known isotopes of potassium, two stable isotopes occur naturally, 39K (93.3% abundance) and 41K (6.7%), while 40K (0.0117%) can also sometimes be considered stable due to its long half-life (1.250 × 109 years). Potassium is the 8th-most abundant element in the Earth’s crust, and the 9th-most abundant in the human body (in atomic percent). Pure potassium is a soft solid that does not freely occur in nature as it oxidizes rapidly in air and reacts violently with water. Potassium is, therefore, generally found in nature in the form of compounds, such as the most common potassium chloride (salt) (KCl), potassium superoxide (KO2), potassium hydroxide (KOH), and potassium carbonate (KHCO3). The basic properties of potassium are summarized in Table 6.1.
Tomatoes in the Diet
Published in Denise Wilson, Sensing the Perfect Tomato, 2019
Potassium can play a major role in reducing hypertension (high blood pressure). High blood pressure has been implicated as a major risk factor in stroke, coronary heart disease, heart failure, chronic kidney disease, and periodontal disease. In a wide range of studies, increasing potassium intake has been shown to significantly reduce both systolic and diastolic blood pressure. The impacts of potassium on reducing blood pressure are so often positive that increasing dietary potassium intake may be the single most important contribution an individual can make to lower the risk of high blood pressure. In fact, some estimate that increasing potassium intake to 3500 mg per day or more can reduce hypertension by 17% in the adult population (Weaver 2013).
Functional Foods and Nutraceuticals: An Overview of the Clinical Outcomes and Evidence-Based Archive
Published in Bhaskar Mazumder, Subhabrata Ray, Paulami Pal, Yashwant Pathak, Nanotechnology, 2019
Manjir Sarma Kataki, Ananya Rajkumari, Bibhuti Bhusan Kakoti
Potassium is a mineral considered crucial to the physiological system around the clock, along with sodium. Sodium excess can precipitate or exacerbate high blood pressure, which can be nullified or reversed by an adequate potassium intake. Adequate potassium intake also improves bone health and prevents kidney stone formation. The adequate intake (AI) for potassium for adults is 4,700 mg per day. Scientific evidence suggests that African Americans and individuals with hypertension especially benefit from increasing their intake of potassium. A low intake of potassium below the AI level for long periods can cause health related issues. Therefore, it is recommended to take potassium fortified foods to fulfil the AI level of required potassium. However, individuals with kidney disease and those who have been taking drugs like ACE inhibitors must consult their physician before taking any potassium supplements. Fruits and vegetables, along with dairy products, are a good natural source of potassium.
Potassium-bearing species in fertiliser obtained by hydrothermal modification of glauconitic siltstones with calcium hydroxide
Published in Mineral Processing and Extractive Metallurgy, 2022
Rodrigo A. O. Peixoto, Kátia D. Oliveira, Cícero N. Ávila-Neto
Evaporite deposits are the main and most important sources of potassium salts. Salts derived from these deposits have high potassium contents, are very soluble in water, and can be easily processed and exploited. The main evaporitic minerals are silvite (KCl), carnalite (KCl·MgCl2·6H2O), kainite (KCl·MgSO4·3H2O), and langbeinite (K2SO4·2MgSO4). Silvinite and carnalite are the most exploited minerals as sources of potassium (Brazil 2001). Potassium salts are primarily used in agriculture, providing one of the three essential elements (N, P and K) for agricultural production. More than 95% of world potash production is used as fertiliser, of which 90% is in the form of KCl, followed by K2SO4 and others (Brazilian Mining Association 2012). Canada, Belarus, and Russia are the leading countries in potash reserves, as well as the largest producers, occupying the top three positions in the world ranking. Together, these countries accounted for around 59% of global potash fertiliser production in 2016 (Brazil 2019).
Subsurface integrity studies on the drilling of Al/B4C/mica hybrid metal matrix composites
Published in Materials and Manufacturing Processes, 2020
S. Eaben Rajkumar, K. Palanikumar, K. Pitchandi, B. Latha
Rb-Rubidium is an alkali metal with a soft structure. Its melting point is 39°C. Rb2O is an alkali metal oxide with a melting point of 400°C. It contains around 91% of Rb and 9% of oxygen. Indium is highly ductile with a melting point of 156°C which also reacts with oxygen thus forming In2O3, SiO2 is a very hard element due to its covalent structure. SiO2 layers provide better oxidation resistance. Element Si is nonreactive at an average temperature but reactive at increased temperature. Selenium (Se) is a nonmetal with a melting point of 217°C. Selenium on reacting with oxygen causes the formation of selenium oxide compound (SeO3)4 which has a melting point of 118°C. Potassium (K) is a soft alkali metal with a melting point of 63.28°C. Potassium oxide is a compound, formed as a result of reaction between oxygen and potassium. It is interesting to note that the melting point of some of the phases and elements in the mica particles are below 220°C. This temperature is well below the working temperature in drilling process. Hence, mica particles melt during drilling process and perfectly act as a lubricant.
Radiological toxicity of some fish and meat tissues consumed in southwestern Nigeria
Published in Human and Ecological Risk Assessment: An International Journal, 2018
Oladele Samuel Ajayi, Emmanuel Oluwanifesii Fatile, Chidiebere Goodluck Dike
Potassium is an essential element necessary in maintaining fluid and electrolyte balance in the bodies of humans and animals. However, 40K, an isotope of potassium is harmful to the body. Potassium accumulates mostly in the bones. Soft tissues only were considered in this study. The mean activity concentration of 40K in the different organs followed this pattern; heart > kidney > tendon > lung > breast > liver > large intestine > small intestine > rumen > beef.