Chemical imaging 1970-01-01
Chemical imaging is a technique used to visualize the spatial distribution of chemical species in a sample. It combines traditional imaging techniques with chemical analysis to provide detailed information about the composition, structure, and properties of materials at a micro or nanoscales. This approach allows researchers to obtain information on the morphology, concentration, and interactions of various chemical components within a sample.
Coblentz Society 1970-01-01
The Coblentz Society is an organization dedicated to advancing the field of molecular spectroscopy, particularly in the infrared. It was founded in 1948 and is named after the physicist and chemist, Frederick Coblentz, who made significant contributions to the field. The society aims to promote research, education, and communication in molecular spectroscopy by organizing workshops, conferences, and publishing scientific papers and newsletters.
Coherent microwave scattering 1970-01-01
Coherent microwave scattering refers to the interaction of microwave signals with objects or media in a manner where the scattered waves maintain a defined phase relationship with the incoming waves. This phenomenon occurs when the dimensions of the scattering objects or features are comparable to the wavelength of the microwaves involved, typically in the range of millimeters to centimeters. In coherent scattering, the scattered waves interfere with each other, resulting in a range of observable effects, including constructive and destructive interference.
Cold vapour atomic fluorescence spectroscopy 1970-01-01
Cold vapor atomic fluorescence spectroscopy (CVAFS) is an analytical technique used primarily for the detection and quantification of trace amounts of mercury and some other elements in various samples. The method is characterized by its high sensitivity and selectivity, making it especially useful in environmental, biological, and industrial analyses.
Collision-induced absorption and emission 1970-01-01
Collision-induced absorption (CIA) and collision-induced emission (CIE) are phenomena that occur when molecules interact with one another during collisions, leading to changes in their energy states. These processes are particularly relevant in the context of molecular gases and contribute to their spectral properties. Here's a breakdown of each concept: ### Collision-Induced Absorption (CIA) - **Definition**: CIA refers to the absorption of light (electromagnetic radiation) resulting from the interactions between colliding molecules.
Colorimeter (chemistry) 1970-01-01
A colorimeter is an analytical instrument used to measure the concentration of colored compounds in a solution. It operates on the principle of colorimetry, which is based on the Beer-Lambert law. This law states that the absorbance of light by a solution is proportional to the concentration of the absorbing substance and the path length of the light through the solution.
Compton edge 1970-01-01
The Compton edge refers to a specific feature observed in the energy spectrum of photons detected in a material, such as a semiconductor or scintillator, when it interacts with gamma rays or high-energy photons. This phenomenon is a result of the Compton scattering process, where an incoming photon collides with an electron and transfers some of its energy to the electron, causing it to be ejected from the atom.
Cross-polarization 1970-01-01
Cross-polarization refers to a phenomenon in which electromagnetic waves (usually radio waves or light) are polarized in directions that are perpendicular to each other. This concept is commonly discussed in optics, telecommunications, and radar technology. ### Key Points about Cross-Polarization: 1. **Polarization Basics**: Polarization describes the orientation of the oscillations of electromagnetic waves.
Curve of growth 1970-01-01
The curve of growth is a concept used in various fields, such as astronomy, biology, and economics, to describe how certain quantities change in relation to time or another variable. Here are a few contexts in which the term is commonly used: 1. **Astronomy**: In astronomy, the curve of growth refers to the relationship between the strength of spectral lines of a star or other celestial object and the abundance of absorbing or emitting material.
Cyclopropyl cyanide 1970-01-01
Cyclopropyl cyanide is an organic compound that consists of a cyclopropyl group (a three-membered carbon ring) attached to a cyanide group (−C≡N).
Deep-level transient spectroscopy 1970-01-01
Deep-Level Transient Spectroscopy (DLTS) is a sensitive and powerful technique used in semiconductor physics and materials science to investigate deep-level electronic states in semiconductors. These deep levels, which are energy states located within the bandgap of a semiconductor, can influence the electrical properties and performance of devices such as diodes, transistors, and solar cells.
Deslandres table 1970-01-01
The Deslandres table, also known as the Deslandres chart, is a tool used in the field of astronomy and astrophysics to facilitate the classification and analysis of celestial bodies' spectra, particularly stars. Named after the French astronomer Camille Deslandres, the table organizes spectral lines based on their wavelengths. In detail, the Deslandres table presents a systematic arrangement of the absorption or emission lines observed in the spectra of stars.
Dicke effect 1970-01-01
The Dicke effect is a phenomenon observed in quantum mechanics, particularly in the context of atomic physics and quantum optics. Named after the physicist Robert H. Dicke, the effect describes the influence of cooperative interactions among atoms, particularly in a dense medium.
Dielectric spectroscopy 1970-01-01
Dielectric spectroscopy, also known as electrical impedance spectroscopy (EIS), is an analytical technique used to study the dielectric properties of materials over a range of frequencies. It involves applying an alternating current (AC) electric field to a sample and measuring how the sample responds, specifically how it polarizes and interacts with the electric field. The response information can provide insights into various physical and chemical properties of the material, including molecular mobility, conductivity, and phase transitions.
Differential dynamic microscopy 1970-01-01
Differential Dynamic Microscopy (DDM) is a quantitative imaging technique used primarily in the study of dynamic processes in biological and soft matter systems. It is particularly valuable for investigating the motion and dynamics of particles in complex environments like colloids, proteins, or cellular systems. The main principles of DDM involve capturing a series of images of a sample over time and analyzing the fluctuations in the intensity of the images to extract information about the movement of particles.
Diffuse correlation spectrometry 1970-01-01
Diffuse correlation spectrometry (DCS) is an advanced optical imaging technique primarily used for non-invasive measurements of blood flow in tissues. It leverages the principles of correlation spectroscopy and diffusive light scattering to assess the dynamics of blood flow at a microvascular level. ### Key Concepts of DCS: 1. **Light Interactions**: DCS involves shining near-infrared (NIR) light into biological tissues.
Diffuse reflectance spectroscopy 1970-01-01
Diffuse reflectance spectroscopy (DRS) is a technique used to analyze the optical properties of materials by measuring the light that is scattered from a sample. This method is particularly useful for studying opaque or semi-opaque samples, where traditional transmission spectroscopy would not be feasible due to light absorption or scattering. ### Key Concepts: 1. **Theory**: When light is incident on a sample, it can be absorbed, reflected, or transmitted.
Diffuse series 1970-01-01
Diffusing-wave spectroscopy 1970-01-01
Diffusing-wave spectroscopy (DWS) is a technique used to study the dynamics of complex, opaque materials, such as colloids, biological tissues, and granular media. This method is based on the scattering of light from a sample that is not transparent, where the light is scattered multiple times due to the complex structure and dynamics of the sample.
Doublet state 1970-01-01
The term "doublet state" is often used in the context of quantum mechanics, particularly when discussing the energy levels of systems with certain symmetries, such as electron configurations in atoms or molecules. In general terms, a doublet state refers to a quantum state characterized by two closely spaced energy levels or components.