Entropy of vaporization 1970-01-01
The entropy of vaporization, often denoted as \( \Delta S_{vap} \), is a thermodynamic quantity that describes the change in entropy when one mole of a substance transitions from the liquid phase to the vapor phase at a given temperature and pressure. It reflects the degree of disorder or randomness in the system. When a liquid evaporates, its molecules gain sufficient energy to overcome intermolecular forces and enter the gas phase, which is characterized by greater molecular movement and spacing.
Edward A. Guggenheim 1970-01-01
Edward A. Guggenheim (1902–1971) was a notable British physicist and chemist, primarily recognized for his contributions to the fields of thermodynamics and physical chemistry. He is particularly well-known for his work on the thermodynamic properties of gases and the development of statistical mechanics. Guggenheim had an influential academic career and published several papers and books that advanced understanding of thermodynamic principles and their applications.
Elias Gyftopoulos 1970-01-01
Elias Gyftopoulos is a notable figure in the fields of thermal sciences and energy engineering. He is recognized for his contributions to the understanding of thermodynamics, heat transfer, and energy systems. Gyftopoulos has held academic positions and has been involved in research and education at various institutions. He is also known for his work on the philosophical and foundational aspects of thermodynamics.
**Thermodynamics** is the branch of physics that deals with the relationships between heat, work, temperature, and energy. It provides a macroscopic perspective on physical systems and allows us to understand how energy is transformed from one form to another and how these transformations affect matter. The fundamental principles of thermodynamics are encapsulated in four laws: 1. **Zeroth Law of Thermodynamics**: Defines thermal equilibrium and establishes temperature as a measurable property.
Thermal Science 1970-01-01
Thermal science is the study of heat, energy transfer, and thermodynamic processes. It encompasses various disciplines that focus on the behavior of energy in relation to temperature, matter, and the laws governing these interactions. The main components of thermal science include: 1. **Thermodynamics**: This branch studies the principles governing heat transfer and work done by or on systems. It includes concepts like the laws of thermodynamics, various thermodynamic cycles, and states of matter.
Basal body temperature 1970-01-01
Basal body temperature (BBT) is the body's temperature at rest, usually measured immediately after waking up, before any physical activity has occurred. This measurement reflects the body's baseline temperature and can be used as an indicator of hormonal changes, particularly in relation to the menstrual cycle. In women, BBT typically fluctuates throughout the menstrual cycle due to hormonal changes.
Bradymetabolism 1970-01-01
Bradymetabolism refers to a slower than normal metabolic rate. It is characterized by a reduced rate of metabolic processes, which can impact how the body processes and uses energy, nutrients, and oxygen. This term is often used in medical contexts to describe conditions that may lead to lower energy expenditure, such as hypothyroidism, where there is an underproduction of thyroid hormones that regulate metabolism.
Chills 1970-01-01
"Chills" can refer to a few different things depending on the context: 1. **Physical Sensation**: In a medical or physiological context, "chills" refer to the sensation of feeling cold, often accompanied by shivering. This can occur in response to a fever, infection, or exposure to cold environments. 2. **Emotional Response**: Chills can also describe a strong emotional reaction, often associated with feelings of pleasure or awe.
Theta characteristic 1970-01-01
In the context of mathematics and specifically in the field of number theory, the term "Theta characteristic" often refers to a certain type of characteristic of a Riemann surface or algebraic curve that arises in the study of Abelian functions, Jacobi varieties, and the theory of divisors. 1. **Theta Functions**: Theta characteristics are closely related to theta functions, which are special functions used in various areas of mathematics, including complex analysis and algebraic geometry.
Theta divisor 1970-01-01
In mathematics, particularly in the theory of abelian varieties and algebraic geometry, a *Theta divisor* is a specific kind of divisor associated with a principally polarized abelian variety (PPAV). More formally, if \( A \) is an abelian variety and \( \Theta \) is a quasi-projective variety corresponding to a certain polarization, then the theta divisor \( \theta \) is defined as the zero locus of a section of a line bundle on \( A \).
Molar heat capacity 1970-01-01
Molar heat capacity (often represented as \( C_m \)) is a physical property of a substance that indicates the amount of heat required to raise the temperature of one mole of that substance by one degree Celsius (or one Kelvin). It reflects how much heat energy is absorbed or released when a substance undergoes a temperature change.
Pressure 1970-01-01
Pressure is defined as the force exerted per unit area on a surface. It is a scalar quantity, meaning it has magnitude but no direction. The formula to calculate pressure (P) is: \[ P = \frac{F}{A} \] where: - \( P \) is the pressure, - \( F \) is the force applied, - \( A \) is the area over which the force is distributed.
Rate of heat flow 1970-01-01
The rate of heat flow, often referred to as heat transfer rate, is a measure of the amount of thermal energy being transferred from one system or body to another over a specific period of time. It is typically expressed in units such as watts (W), where one watt is equivalent to one joule per second (J/s). Heat flow occurs through three primary mechanisms: 1. **Conduction**: The transfer of heat through a material without the movement of the material itself.
Recalescence 1970-01-01
Recalescence is a phenomenon observed in materials, particularly in metallurgy, during the phase transformation from a liquid to a solid state, specifically during solidification. It refers to the rise in temperature that can occur in a material as it transitions from a supercooled liquid to a solid phase. When a metal or alloy is cooled past its freezing point, it may continue to cool below its equilibrium solidification temperature, entering a metastable state.
Reduced properties 1970-01-01
"Reduced properties" typically refer to a set of thermodynamic properties that are used to characterize the behavior of substances in relation to their critical points. These properties are particularly useful in the study of gases and other substances in various thermodynamic processes. The reduced properties are defined as follows: 1. **Reduced Temperature (\( T_r \))**: This is defined as the ratio of the temperature of the substance to its critical temperature (\( T_c \)).
Residual property (physics) 1970-01-01
In physics, the term "residual property" can refer to various concepts depending on the context, but it is most commonly associated with materials science, thermodynamics, and fluid mechanics. Here are a couple of common interpretations: 1. **Residual Stress**: This refers to internal forces that remain in a material after the original cause of the stresses has been removed. Residual stresses can significantly affect the material's strength, durability, and overall performance.
Boiler (water heating) 1970-01-01
A boiler is a device used for heating water or producing steam through the combustion of fuel. It is an essential component in various heating applications, including residential heating, industrial processes, and power generation. Here's how it works and some key components and types: ### How it Works 1. **Fuel Source**: Boilers can use various fuel sources, such as natural gas, oil, coal, electricity, or biomass, to generate heat.
Cryogenic engineering 1970-01-01
Cryogenic engineering is a specialized field of engineering that deals with the production and application of very low temperatures, typically below -150 degrees Celsius (approximately -238 degrees Fahrenheit or 123 Kelvin). At these temperatures, the properties of materials can change significantly, and many gases become liquids, which can be exploited for various industrial and technological processes. Key aspects of cryogenic engineering include: 1. **Cryogenic Liquefaction**: Processes to convert gases like nitrogen, helium, and hydrogen into liquids.
Cryometer 1970-01-01
A cryometer is an instrument used to measure very low temperatures, typically in the cryogenic range, which is generally considered to be below -150 degrees Celsius (-238 degrees Fahrenheit). Cryometers can be used in various scientific and industrial applications, including material testing, fundamental physics research, or in the cooling processes of technologies such as superconductors. Different types of cryometers operate on various principles.
Apparent molar property 1970-01-01
Apparent molar properties refer to certain thermodynamic properties of a solution that can be associated with the individual components in that solution, adjusted to a standard unit (typically per mole of solute). These properties reflect how the presence of a solute affects the overall behavior of a solution compared to the pure solvent. The concept of apparent molar properties is useful in understanding solutions, especially when discussing colligative properties, activity coefficients, and interactions between solute and solvent molecules.