Transmission electron microscopy

Atomic mass: the mass of an atom of a chemical element expressed in atomic mass units; approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes Molar mass: a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by the amount of substance Mole: the amount of a substance contained in 6.02 x 10²³ particles of that substance…

Topic 1: Chemical bonding 1.True or False: An Ion is when an atom gains or loses an electron. 2.What is a Cation? An ion with a (+) charge. 3.True or False: An Anion does not have a (-) charge. 4.What type of bonding transfers electrons? Ionic bonding 5.What are all the types of chemical bonds? Ionic, Covalent, and Metallic bonding. 6.What do you call an element that has different forms . Isotopes 7.Which type of bonding is the “strongest”? Ionic bonding 8.True or False: Ionic bonds are formed…

ions and electrons, the positive ions are attracted to the outside of the tube. The electrons are attracted to a metal wire running down the inside of the tube maintained at a high positive voltage. Many electrons travel down the wire making a burst of current in a circuit connected to it. The electrons make a meter needle deflect and you can hear a click every time radioactive…

The garnet ferrites have the general formula RFe5O12, where R is one of the rare earth metal ions (Y, Gd, Dy, Sm, Eu, Ho, Er, Tm, Tb and Lu). The first trail for synthesis of garnet Yttrium ferrite (Y3Fe5O12) was done by Bertaut and Forret in 1956 [39], this trial was followed by another one in 1957 when Geller and Gilleo prepared and investigated Gd3Fe5O12 [40]. The garnet ferrites have complex crystal structure with cubic shape. The cubic unit cell of garnet ferrites R3Fe5O12 contains 8…

The Physics of PET Scans All elements are composed of atoms, which are composed of small particles called protons, neutrons, and electrons. The nucleus of an atom is made of a tightly packed collection of protons and neutrons. You would think that with positively charged protons being packed so closely together the nucleus would fall apart, however this is not the case. There is an attractive force called the “nuclear force” which is able to overcome the repulsive force of the adjacent…

D1 X-ray spectrum: X-rays are created when a component is attacked with high energy electron. So when a high energy electron attacks the target electron in an atom it, this leads to the target electron being ejected from the inner shell of the atom. Whereas bremsstrahlung radiation is when radiation is given off by a particle that is charged, usually an electron, because of acceleration which is caused by another charged particle, usually an atomic nucleus. The x ray beam from an x ray is…

Photography dates back to 1839 as a result of the camera obscura. The camera obscura was a photographic medium that captured beautiful pictures, drawings, objects, still life and any views. Louis Jacques Mande Daguerre and William Henry Fox Talbot invented separate processes in London and Paris called the daguerreotype and the calotype. They both implemented the camera obscura to make their inventions. Both Daguerre and Talbot were passionate about and envisioned reproducing nature into…

mechanism starts with a nucleophilic attack from the alcohol, in this case sec-phenethylalcohol, to the PCl3 causing a chlorine atom to leave. The nitrogen from dimethylaniline grabs the hydrogen from the alcohol that’s attached to the phosphate and the electrons from the O-H are transferred to oxygen. Then another molecule of the alcohol attacks the phosphate one again cleaving the P-Cl bond. Then another molecule of…

In this equation, x and y denotes the number of moles of RE and Mn atoms per formula unit of the structure, respectively. The RE and Mn represent the theoretical magnetic moment of trivalent free RE3+ ions and divalent Mn2+ ions respectively. The experimental values of total magnetic moments were found to be smaller than the calculated values (Table xyz). The crystal field effects can lead to lower value of magnetic moments for RE3+ ions in these compositions as compared to free RE3+ ions,…

Radiology Research paper Scientist Wilhelm Roentgen accidentally discovered X-rays while studying the pathway of electricity. He realized this when he saw objects in the picture that wouldn’t usually appear in a normal photograph. Roentgen’s discovery was soon after, advanced further by Dr. Harvey Cushing in the first diagnostic clinical X-ray. 1902 was the first year they were used for ground breaking brain surgery, he used the technology to view and assist removing malignant and non-malignant…