Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium applications: - Source of neutrons: as Po-BeO - Radioisotope thermoelectric energy source - Alpha particles source - Brushes with Po to eliminate static charges from different surfaces - Material in radiochemistry studies Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.m Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Polonium chemical properties Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
The relationship between microM and nM is a factor of 1000. MicroM (or micromolar) is 1 millionth of 1 molar (1 x 106 microM = 1 M), and nM (nanomolar) is 1 billionth of 1 molar (1 x 109 nM = 1 M) See the link below the answer for the relationship between all metric prefixes.
One metre = 106 micrometres 1.4 micrometres3 x 1/106m/microm x 1/106m/microm x 1/106m/microm= 1.4x10-216 m3 a litre is 100 cm3 One meter = 100 cm 1 m3 x 100cm/m x 100cm/m x 100cm/m = 1x106 cm3 1.4 x10-216 m3 x 1x106cm3/m3 = 1.4 x 10-210 litres One metre = 106 micrometres 1.4 micrometres3 x 1/106m/microm x 1/106m/microm x 1/106m/microm= 1.4x10-216 m3 a litre is 100 cm3 One meter = 100 cm 1 m3 x 100cm/m x 100cm/m x 100cm/m = 1x106 cm3 1.4 x10-216 m3 x 1x106cm3/m3 = 1.4 x 10-210 litres
So M is moles per litre. Therefore microM is micromoles per litre. There are 1000 litres in a metre cubed. There are also 1000 micromoles in a millimole. Though these cancel each other out, so micromolar is actually the same as millimoles per metre cubed.
four new curcurmin analogs (compounds 1, 2, 17 and 18) were synthesized. 17 [3,5-bis(4-hydroxy-3-methoxy-5-methylcinnamyl)N-methylpiperidone] showed high activity with GI50, TGI, and LC50 MG-MID values of 21.3, 70.7, and 97.7 microM, respectively. 18 [3,5-bis(4-hydroxy-3-methoxy-5-methylcinnamyl)-N-ethylpiperidone] showed the highest activity in this study with GI50, TGI, LC50 MG-MID values of 4.4, 33.8, 89.1 microM, respectively. 18 is even more active than curcumin with GI50, TGI, LC50 MG-MID values of 38.4, 35.6, 66.0 microM; respectively. 8 showed moderate selectivity towards Leukemia cell line-subpanel with a ratio of 5.6 (curcumin ratio: 1.2 for the same subpanel). The in vitro anti-tumor screening reveals that the results go hand in hand with the in vitro free radical scavenging effects. The antioxidant effect of these compounds depends mainly on the stabilization of the formed phenoxy free radical for which the p-hydroxy phenyl moiety is essential. o-substitution by electron-donating groups like the o-methoxy group (and to a even higher degree by the ethoxy group) increases the stability of phenoxy free radical, hence increasing both free scavenging and anti-tumor effects. Increasing the alkyl group chain on the N in the series of substituted N-alkyl piperidones as well as the extension of conjugation, increases the stabilization of phenoxy free radical and thereby the activity towards both free radical scavenging and anti-tumor effects. This may be attributed to an increased positive inductive effect and/or increased lipophilicity of the new compounds, a fact which is proven by the superior activities of compounds 17 and 18.
Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Polonium chemical properties:Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium physical propertiesDensity: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Plutonium is a greyish rare earth metal with a dull, silvery surface. It's probably a bit rough when not machined or cast and processed. It oxidizes in the presence of air, and can swell up to 70% during oxidation and break the container it's in. Its surface can break up (spall, ejecta) and since plutonium is a pyrophoric material, it can burn in air. It must be handled in an inert gas atmosphere and is therefore usually coated with nickel or gold, and alloyed with gallium, especially in nuclear weapon pits.
Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium applications: - Source of neutrons: as Po-BeO - Radioisotope thermoelectric energy source - Alpha particles source - Brushes with Po to eliminate static charges from different surfaces - Material in radiochemistry studies Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.m Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Chemical properties of polonium: Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Chemical properties of polonium: Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.meter Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K
Polonium was discovered by Marie Curie and Pierre Curie in 1898.The electron configuration of polonium is [Xe]4f14.5d10.6s2.6p4. Studying residues of uranium ores Marie Curie and Pierre Curie found that these residues are more radioactive than uranium; they attributed this radioactivity to unknown elements. They isolated these elements and named these elements polonium and radium. Polonium is between the most poisonous materials; the LD5o for polonium-210 is 1 microgram. Now polonium is not extracted from ores; it is obtained using this reaction:Bi-209 + n----------------Bi-210--------------Po-210 Polonium with the atomic number 84 is in the group 16 and period 6 of the periodic table of Mendeleev. Some compounds of polonium are: PoO, PoO2, PoO3, PoH2, halides as PoX2, PoX4, PoX6 and the strange class of polonides (compounds of polonium with other metals). The Pauling electronegativity is 2. Possible valences are: 2, 4, 5, 6, -2. Polonium applications: - Source of neutrons: as Po-BeO - Radioisotope thermoelectric energy source - Alpha particles source - Brushes with Po to eliminate static charges from different surfaces - Material in radiochemistry studies Polonium physical properties Density: alpha phase: 9,196 g/cm3; beta phase: 9,398 g/cm3 Melting point: 254 0C Boiling point: 962 0C Heat of fusion: 13 kJ/mol Heat of vaporization: 102,91 kJ/mol Molar heat capacity: 26,4 J/mol.K Electrical resistivity: 0, 40 microohm.m Thermal conductivity: 20 W/m.K Atomic radius (empirical): 168 pm First ionization energy: 812,1 kJ/mol Crystalline structure: alpha-phase: cubic; beta phase: rhombohedral Magnetism: monmagnetic Thermal expansion: 23,5 microm/m.K