![]() ![]() Simple microscope, Compound microscope, Telescope, Prism Others devices are based on the phenomenon of electromagnetism while magnet is not.Ģ1. Loud speaker, Magnet, Microphone, Electric motor Voltmeter, Ammeter, Galvanometer, Electric motorĮlectric motor is a device which converts electrical energy into mechanical energy whereas other devices are used to measure current and potential difference in a circuit.ġ2. ![]() Magnesium is placed in period 3 while others are placed in period 2 of the modem periodic table.ġ1. Potassium is placed in group 1 while others are placed in group 2 of the modern periodic table. Moseley arranged elements in an increasing order of their atomic numbers whereas others arranged elements based on their atomic masses.īoron is placed in group 13 while others are placed in group 17 of the modem periodic table.Ĭalcium is a s-block element while others are p-block elements.ĩ. Currently, two boron compounds are being used in clinical research into BNCT: BPA, which has the structure of an amino acid, and BSH, which has a cluster-like structure.Gallium is a metal while others are metalloids.Ħ. They must exhibit low toxicity since they are administered directly into the blood.Īdditionally, research to date has pointed to the importance of properties such as the balance of hydrophobic and hydrophilic tendencies and the proportion of each molecule’s chemical makeup accounted for by the element boron. They must not be metabolized but must instead remain in tumor tissue for a certain period of time, They must not have any pharmaceutical effects themselves and must function only as a boron delivery molecule (in this property, they differ substantially from normal drugs), ![]() They must accumulate selectively (the ratio of the concentration in tumor cells to the concentration in normal cells must be greater than or equal to 3) and in large volumes (at a 10B concentration of 20 to 40 ppm), High-purity boron compounds for use in BNCT 【1】Properties required of 10B compounds and boron agentsīoron compounds for use in BNCT must exhibit the following principal properties: Pharmaceutical-grade boron compounds are manufactured using this enriched 10B in Japan, the Czech Republic, and other countries. Currently, only a small number of countries, including Japan and the U.S., have plants capable of manufacturing enriched 10B by sorting 10B and 11B in natural boron compounds and supplying it in large quantities. Consequently, high-purity 10B (enriched 10B) is necessary as a raw material in order to manufacture the boron agents that are used in BNCT. Natural boron exists in two isotopes with mass numbers of 10 ( 10B) and 11 ( 11B) in a proportion of about 1:4, and only 10B is capable of absorbing (capturing) thermal neutrons. Although it is common in the form of boric acid in rock, groundwater, surface water, and plants, it is not present in the human body. Developing high-performance boron agents to selectively concentrate boron in tumor cellsīoron-10 and the manufacture of high-purity, enriched boron-10īoron is a chemical element with atomic number 5 in group 13 and period 2 of the periodic chart. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |