What is the effect of gamma rays on matter?5 answersGamma rays have various effects on matter. They can penetrate matter easily due to their high energy, making them useful for gamma spectrometry without the need to eliminate the matrix. Gamma rays have been used to alter the protein allergen structure in foods, potentially minimizing allergic reactions. In the study of dark matter, the existence of new gauge U(1) symmetry implies the presence of a Coulomb-like interaction, leading to the enhancement of dark matter annihilation through gamma radiation. Irradiation of adenosine triphosphate (ATP) with gamma rays results in the release of free adenine and destruction of ribose, with the primary attack occurring at the 1'carbon atom.
Simply what is the Photoelectric effect on semiconductors?4 answersThe photoelectric effect on semiconductors refers to the phenomenon where the absorption of light generates an electric current in the material. This effect is observed in various types of semiconductors, including undoped semiconductors, multivalley semiconductors, and semiconductors with insulator-semiconductor stacks. In the case of undoped semiconductors, the effect is due to the intrinsic shift current that occurs when the material is exposed to an alternating electric field. In multivalley semiconductors, the diffusion of photoexcited electrons in different valleys leads to the generation of an electromotive force through the Dember photovoltaic effect. In semiconductors with insulator-semiconductor stacks, the capacitance of the stack is modified by the generation of carriers in the space-charge region, resulting in a change in the wetting contact angle of a droplet on the surface. These effects have potential applications in areas such as optofluidics and microfluidics.
What is the effect of the photoelectric effect on the conductivity of semiconductors?5 answersThe photoelectric effect has an effect on the conductivity of semiconductors. In unipolar multivalley semiconductors, the diffusion of photoexcited nonequilibrium heavy and light electrons is a correlated process, similar to ambipolar diffusion in the case of an electron-hole plasma. The light-induced intervalley transitions in multivalley semiconductors result in an imbalance between the subsystems of light and heavy electrons, leading to the electromotive force (emf) through the Dember photovoltaic effect. The emf in a "metal-semiconductor-metal" structure is determined by the conductivity of the heavy and light electron subsystems, as well as the surface conductivity of the metal-semiconductor interface. Additionally, the photoconductivity of semiconductors, such as germanium, silicon, and certain intermetallic compounds, can be controlled to study other processes and has practical applications in these materials.
How does gamma rays impact Human?3 answersGamma rays have significant impacts on human health. Exposure to gamma radiation can cause damage to proteins, DNA, and other cellular components, leading to various deleterious effects on the body. Gamma radiation can also alter the molecular structure of medical devices and tissue allografts, affecting their biomechanical properties. Additionally, ionizing radiation can cause damage to organs such as the brain, skin, lungs, gastrointestinal tract, and blood. The effects of gamma radiation can range from acute symptoms such as skin burns and radiation sickness to long-term health effects like cancer and cardiovascular disease. It is important to take measures to protect against radiation exposure and conduct further studies to ensure the safety of irradiated food for human consumption.
How does a photoelectric chemical cell work?5 answersA photoelectrochemical cell is a device that converts solar energy into useful fuels or electricity. It consists of a photoactive electrode, an electrolyte, and an auxiliary electrode. The photoactive electrode receives light through a light window and initiates a redox reaction. The electrolyte facilitates the movement of ions between the electrodes, while the auxiliary electrode completes the circuit. The cell operates in three main modes: regenerative PECs, where no Gibbs function change occurs in the cell; photoelectrolytic cells, where two separate redox reactions are driven at the electrodes; and cells for photoelectrocatalysis, which have potential applications in environmental purification. Advances in cell design and materials have led to increased efficiency, corrosion control, and long-term stability. Nanostructured materials and dye sensitization have also been developed to enhance performance.
What are the effects of different gamma-ray doses on the optical properties of silver-polyaniline nanocomposites?5 answersThe effects of different gamma-ray doses on the optical properties of silver-polyaniline nanocomposites were investigated in several studies. It was found that gamma irradiation caused modifications in the optical properties of the nanocomposites. The direct bandgap of the nanocomposites decreased with increasing gamma irradiation, indicating damage to the ordered structure and an increase in amorphous regions. The gamma irradiation also resulted in an increase in the amorphous phase and a decrease in the optical energy gap of the nanocomposites. The nanocomposites synthesized under gamma-ray irradiation exhibited PANI nanofibers and Ag nanoparticles, and their transport behavior was well fitted with the variable-range-hopping model. Additionally, the nanocomposites showed a shift in the glass transition temperature towards higher temperatures after irradiation. The synthesis of polyaniline and silver nanoparticles in the nanocomposites was achieved through both sonochemical and ionizing radiation techniques.