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Reaction Calorimeter
A reaction calorimeter is a calorimeter that measures the amount of energy released (in exothermic reactions) or absorbed (in endothermic reactions) by a chemical reaction. Methods Heat flow calorimetry Heat flow calorimetry measures the heat flowing across the reactor wall and quantifies this in relation to other energy flows within the reactor. : Q = U A (T_r-T_j) where: :Q → process heating (or cooling) power (W) :U → overall heat transfer coefficient (W/(m2K)) :A → heat transfer area (m2) :T_r → process temperature (K) :T_j → jacket temperature (K) Heat flow calorimetry allows the user to measure heat while the process temperature remains under control. While the driving force is measured with a relatively high resolution, the overall heat transfer coefficient or the calibration factor is determined by calibration before and after the reaction takes place. These factors are affected by the product composition, process temperature, agitation rate, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibrium Chemistry
Equilibrium chemistry is concerned with systems in '' chemical equilibrium''. The unifying principle is that the free energy of a system at equilibrium is the minimum possible, so that the slope of the free energy with respect to the reaction coordinate is zero. This principle, applied to mixtures at equilibrium provides a definition of an equilibrium constant. Applications include acid–base, host–guest, metal–complex, solubility, partition, chromatography and redox equilibria. Thermodynamic equilibrium A chemical system is said to be in equilibrium when the quantities of the chemical entities involved do not and ''cannot'' change in time without the application of an external influence. In this sense a system in chemical equilibrium is in a stable state. The system at chemical equilibrium will be at a constant temperature, pressure or volume and a composition. It will be insulated from exchange of heat with the surroundings, that is, it is a closed system. A change ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calorimetry
In chemistry and thermodynamics, calorimetry () is the science or act of measuring changes in '' state variables'' of a body for the purpose of deriving the heat transfer associated with changes of its state due, for example, to chemical reactions, physical changes, or phase transitions under specified constraints. Calorimetry is performed with a calorimeter. Scottish physician and scientist Joseph Black, who was the first to recognize the distinction between heat and temperature, is said to be the founder of the science of calorimetry. Indirect calorimetry calculates heat that living organisms produce by measuring either their production of carbon dioxide and nitrogen waste (frequently ammonia in aquatic organisms, or urea in terrestrial ones), or from their consumption of oxygen. Lavoisier noted in 1780 that heat production can be predicted from oxygen consumption this way, using multiple regression. The dynamic energy budget theory explains why this procedure is corre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Controlled Lab Reactor
In chemistry, a Controlled Lab Reactor or CLR is any reaction system where there is an element of automated control. Generally these devices refers to a jacketed glass vessel where a circulating chiller unit pumps a thermal control fluid through the jacket to accurately control the temperature of the vessel contents. Additional to this, it is common to have a series of sensors (temperature, pH, pressure) measuring and recording parameters about the reactor contents. It is additionally possible to control pumps to act on the reactor. Historical background The first controlled lab reactors were derived from the control systems used in chemical plant A chemical plant is an industrial process plant that manufactures (or otherwise processes) chemicals, usually on a large scale. The general objective of a chemical plant is to create new material wealth via the chemical or biological transfor ...s. These were generally dedicated to specific tasks as reprogramming was difficult. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermodynamics
Thermodynamics is a branch of physics that deals with heat, Work (thermodynamics), work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of thermodynamics, which convey a quantitative description using measurable macroscopic physical quantity, physical quantities but may be explained in terms of microscopic constituents by statistical mechanics. Thermodynamics applies to various topics in science and engineering, especially physical chemistry, biochemistry, chemical engineering, and mechanical engineering, as well as other complex fields such as meteorology. Historically, thermodynamics developed out of a desire to increase the thermodynamic efficiency, efficiency of early steam engines, particularly through the work of French physicist Nicolas Léonard Sadi Carnot, Sadi Carnot (1824) who believed that engine efficiency was the key that could help France win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flow Reactor
Continuous reactors (alternatively referred to as flow reactors) carry chemical materials as a flowing stream. Reactants are continuously fed into the reactor and emerge as continuous stream of product. Continuous reactors are used for a wide variety of chemical and biological processes within the food, chemical and pharmaceutical industries. A survey of the continuous reactor market will throw up a daunting variety of shapes and types of machine. Beneath this variation however lies a relatively small number of key design features which determine the capabilities of the reactor. When classifying continuous reactors, it can be more helpful to look at these design features rather than the whole system. Batch versus continuous Reactors can be divided into two broad categories, batch reactors and continuous reactors. Batch reactors are stirred tanks sufficiently large to handle the full inventory of a complete batch cycle. In some cases, batch reactors may be operated in semi batc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batch Reactor
A batch reactor is a chemical reactor in which a non-continuous reaction is conducted, i.e., one where the reactants, products and solvent do not flow in or out of the vessel during the reaction until the target reaction conversion is achieved. By extension, the expression is somehow inappropriately used for other batch fluid processing operations that do not involve a chemical reaction, such as solids dissolution, product mixing, batch distillation, crystallization, and liquid/liquid extraction. In such cases, however, they may not be referred to as reactors but rather with a term specific to the function they perform (such as crystallizer, bioreactor, etc.). Many batch processes are designed on the basis of a scale-up from the laboratory, particularly for the manufacture of specialty chemicals and pharmaceuticals. If this is the case, the process development will produce a ''recipe'' for the manufacturing process, which has many similarities to a recipe used in cookery. A typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid Dynamics
In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids – liquids and gases. It has several subdisciplines, including (the study of air and other gases in motion) and (the study of water and other liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moment (physics), moments on aircraft, determining the mass flow rate of petroleum through pipeline transport, pipelines, weather forecasting, predicting weather patterns, understanding nebulae in interstellar space, understanding large scale Geophysical fluid dynamics, geophysical flows involving oceans/atmosphere and Nuclear weapon design, modelling fission weapon detonation. Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Fluids
Thermofluids is a branch of science and engineering encompassing four intersecting fields: *Heat transfer *Thermodynamics *Fluid mechanics *Combustion The term is a combination of "thermo", referring to heat, and "fluids", which refers to liquids, gases and vapors. Temperature, pressure, equations of state, and transport laws all play an important role in thermofluid problems. Phase transition and chemical reactions may also be important in a thermofluid context. The subject is sometimes also referred to as "thermal fluids". Heat transfer Heat transfer is a discipline of thermal engineering that concerns the transfer of thermal energy from one physical system to another. Heat transfer is classified into various mechanisms, such as heat conduction, convection, thermal radiation, and phase-change transfer. Engineers also consider the transfer of mass of differing chemical species, either cold or hot, to achieve heat transfer. Sections include : * Energy transfer by heat, work ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lara Coflux
Lara may refer to: People * Lara (name), can be a given name or a surname in several languages * Lara (mythology), a naiad nymph, daughter of the river Almo in Ovid's ''Fasti'' Places *Lara (state), a state in Venezuela * Electoral district of Lara, an electoral district in Victoria, Australia *Lara, Antalya, an urban district in Turkey * Lara, Victoria, a township in Australia **Lara railway station * Lara de los Infantes, a place in Spain *Punta Lara, a city in Buenos Aires Province, Argentina *LARA, the airport code for Jacinto Lara International Airport, in Barquisimeto, Venezuela Art, entertainment, and media * ''Lara'' (film), 2019 film * Lara (character), the biological mother of the comic book character Superman * Lara (novel), 1997 novel-in-verse by Bernardine Evaristo * Lara & Reyes, an instrumental band * '' Lara's Theme'', the generic name given to a leitmotif written for the film ''Doctor Zhivago'' (1965) by composer Maurice Jarre * ''Lara, A Tale'' (1814), a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
