Stash
Subham Bera's Stashed Knowledge
quantum mechanics
Quantum mechanics is the science of the very small. It explains the behavior of matter and its interactions with energy on the scale of atomic and subatomic particles. By contrast, classical physics explains matter and energy only on a scale familiar to human experience, including the behavior of astronomical bodies such as the Moon. Classical physics is still used in much of modern science and technology. However, towards the end of the 19th century, scientists discovered phenomena in both the large (macro) and the small (micro) worlds that classical physics could not explain.[1] The desire to resolve inconsistencies between observed phenomena and classical theory led to two major revolutions in physics that created a shift in the original scientific paradigm: the theory of relativity and the development of quantum mechanics.[2] This article describes how physicists discovered the limitations of classical physics and developed the main concepts of the quantum theory that replaced it in the early decades of the 20th century. It describes these concepts in roughly the order in which they were first discovered. For a more complete history of the subject, see History of quantum mechanics.
Subham Bera
defect in crystals
It is a truism that the more we learn about anything the more complex that subject becomes. This is especially true of our understanding of the exact arrangement of atoms or ions which make up solid materials.The rapid development and improvement of the techniques by which defects solids are detected and characterized, and which form the subject matter of this book, have necessitated constant revision of our concepts of perfect and defective solids. It is, for example, no longer adequate to confine our attention to isolated point defects without also considering their aggregation to form more complex defect centres and eventually even separate phases, their relationship with non-stoichiometry and their interactions with each other and with the linear and planar defects with which they co-exist. Similarly, the precise structural information now available for many materials reveals that non-stoichiometric phases may exist as modulated structures in which the composition may vary in a continuous fashion to yield commensurate, semi-commensurate and incommensur-ate structures. The presence of shear planes also changes the composit-ion of non-stoichiometric phases.
control loop reduction
Closed loop control, also known as feedback control, eliminates the shortcomings of open loop control. Here, the response or the actual result is continuously compared with the desired result, and the control output to the process is modified and adjusted to reduce the deviation, thus forcing the response to follow the reference. Effects of the disturbances (external and/or internal) are automatically compensated for. This scheme is superior, complex, and expensive. It is used for more demanding applications and is commonly applied in continuous process automation as discussed in forthcoming sections.
controllers
A controller, in a computing context, is a hardware device or a software program that manages or directs the flow of data between two entities. In computing, controllers may be cards, microchips or separate hardware devices for the control of a peripheral device. In a general sense, a controller can be thought of as something or someone that interfaces between two systems and manages communications between them. Here are a few examples of controllers: A graphics card is an integrated circuit card in a computer or, in some cases, a monitor that provides digital-to-analog conversion, video RAM, and a video controller so that data can be sent to a computer's display.
conductivity measurement
Electrical conductivity is the ability of a material to build an electric current in the presence of an electric field. Metals are good conductors and therefore exhibit a large conductivity. Insulators are bad conductors having a very small, close-to-zero conductivity. In liquids, particularly aqueous solutions, the conductivity is greatly affected by the amount of dissolved charged atoms or molecules (ions). Conductivity measurements are widely used in industrial and environmental applications as a simple and inexpensive way to control the ionic content in a solution. In water purification systems, the conductivity is monitored at different stages of the process. Since the mobility of the dissolved ions is affected by temperature, these monitoring systems are required to either control the process temperature or to compensate readings according to the sample temperature.
particle dynamics
This chapter discusses force and motion in relation to particle dynamics. Any influence that can cause a body to accelerate is called a force. The study of the motion of particles in terms of the forces associated with that motion is called particle dynamics. A body has a constant velocity unless it is acted on by a net force. Many individual forces may act on a body, but the resultant or net force must be equal to zero if the body is not to accelerate. The assertion that a body on which there is no net force experiences no acceleration implies that a moving body will maintain a constant velocity forever unless acted on by a net force. Newton's first law, however, does not apply to all reference frames, the coordinate systems. The application of Newton's laws usually means solving dynamics problems, which are commonly stated as word problems. The basic issue in dynamics problems is solving the fundamental dynamic equation, ∑F = ma. Perhaps the most common form of problem in dynamics requires that the acceleration of a given mass be determined when the mass is subjected to known forces. Sometimes more than one mass is involved; occasionally the mass is the unknown quantity to be determined
hot wire anemomelies
it is hot wire anemomelis.
an oil refinary
An oil refinery or petroleum refinery is an industrial process plant where crude oil is transformed and refined into more useful products such as petroleum naphtha, gasoline, diesel fuel, asphalt base, heating oil, kerosene, liquefied petroleum gas, jet fuel and fuel oils.[1][2][3] Petrochemicals feed stock like ethylene and propylene can also be produced directly by cracking crude oil without the need of using refined products of crude oil such as naphtha.[4][5] Oil refineries are typically large, sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units, such as distillation columns. In many ways, oil refineries use much of the technology, and can be thought of, as types of chemical plants. The crude oil feedstock has typically been processed by an oil production plant. There is usually an oil depot at or near an oil refinery for the storage of incoming crude oil feedstock as well as bulk liquid products. Petroleum refineries are very large industrial complexes that involve many different processing units and auxiliary facilities such as utility units and storage tanks. Each refinery has its own unique arrangement and combination of refining processes largely determined by the refinery location, desired products and economic considerations. An oil refinery is considered an essential part of the downstream side of the petroleum industry.
computer language
Are you aiming to become a software engineer one day? Do you also want to develop a mobile application that people all over the world would love to use? Are you passionate enough to take the big step to enter the world of programming? Then you are in the right place because through this article you will get a brief introduction to programming. Now before we understand what programming is, you must know what is a computer. A computer is a device that can accept human instruction, processes it and responds to it or a computer is a computational device which is used to process the data under the control of a computer program. Program is a sequence of instruction along with data. The basic components of a computer are: Input unit Central Processing Unit(CPU) Output unit
TENSOR
In mathematics, a tensor is an algebraic object that describes a (multilinear) relationship between sets of algebraic objects related to a vector space. Objects that tensors may map between include vectors and scalars, and, recursively, even other tensors. Tensors can take several different forms – for example: scalars and vectors (which are the simplest tensors), dual vectors, multilinear maps between vector spaces, and even some operations such as the dot product. Tensors are defined independent of any basis, although they are often referred to by their components in a basis related to a particular coordinate system.
PARTICLE SIZE ANALYZER
Particle Size Analyzer (PSI) is an on-line analyzer for mineral slurries without sampler. It can provide accurate and real-time analysis which is suitable for measuring particle size in the range of 20μm-1000μm. PSI can be used for monitoring and optimizing system (expert system) to minimize reagent consumption, maximize recoveries and improve grinding performance
DIFFERENTIAL EQUATION
A Differential Equation is an equation with a function and one or more of its derivatives: differential equation y + dy/dx = 5x Example: an equation with the function y and its derivative dy/dx Differential Equations can describe how populations change, how heat moves, how springs vibrate, how radioactive material decays and much more. They are a very natural way to describe many things in the universe.