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Computer micro

Iadds89] Ladd, S.R., Computer life creating mutations on your very own computer, Micro Cornucopia 49, Sept/Oct 1989, 50-56. [Pg.770]

The sample environment was filled with He gas to prevent the argon X-ray emission from air. Beam scanning, data acquisition, evaluation and the generation of elemental maps were controlled by a computer. Micro-PIXE measurements were performed with a scanning 2.5MeVH+ microbeam accelerated by the 3 MV single-end accelerator. The beam diameter was 1-2 pm, so that individual particles could be analysed. The beam current was < 100 pA and the irradiation time was about 3(M0 min. [Pg.103]

Every body needs sufficient knowledge of chemistry to function effectively in present day society. At present our society is being influenced by new drugs, synthetic materials, green revolutions in agriculture, micro-computers, micro-electronics etc. [Pg.12]

Tworzydlo, W.W., et al.. Computational micro- and macroscopic models of contact and friction formulation, approach and applications. Wear, 1998.220 p. 113-140. [Pg.154]

Ivanov, I. and Tabiei, A. (2001), Three-dimensional computational micro-mechanical model for woven-fabric composites . Composites Structures, 54, 489-496. [Pg.179]

COMPUTER-AIDEDDESIGNANDMANUFACTURING(CAD/CAM)] (Vol7) Sokd-phase micro extraction... [Pg.913]

R. D. McCarty, Interactive FORTRAN Programs for Micro Computers to Calculate the Thermo Physical Properties of Twelve Fluids [MIPROPS], NBS Technical... [Pg.18]

Eor all the excitement and enthusiasm of the computer architects, these computers did not meet with great success in the marketplace, and few companies remain as viable entities. One of the primary reasons for their demise seems to have been the simultaneous rise of the RISC work stations, which killed off numerous other architectural initiatives, hence the term killer micros (11). [Pg.93]

A recent victim of the killer micros was Evans and Sutherland s parallel computer development effort, halted ia 1990. Their architecture combiaed a small number of approximately 1-MFLOPS processors iato semi-iadependent functional units. Several of these units could, ia turn, be combiaed to form a processor hierarchy, building up to systems that were expected to cost between 1 and 8 million dollars. With the advent of lO-MFLOPS uniprocessor killer micros, such an architecture became irrelevant and the project was halted. The RISC killer micro could deUver the same level of performance as could the combiaed efforts of 10 of the 1-MFLOPS processors, evea with the unlikely assumptioa that the problem could be perfectiy parallelized across 10 processors. [Pg.95]

The use of impedance electrochemical techniques to study corrosion mechanisms and to determine corrosion rates is an emerging technology. Elec trode impedance measurements have not been widely used, largely because of the sophisticated electrical equipment required to make these measurements. Recent advantages in micro-elec tronics and computers has moved this technique almost overnight from being an academic experimental investigation of the concept itself to one of shelf-item commercial hardware and computer software, available to industrial corrosion laboratories. [Pg.2437]

Central processing unit (CPU) This is in the form of a micro controller and can be called the brain of the PLC. It computes and analyses the various data fed into it. It acts like a comparator and makes decisions on the corrective action necessary to fulfil process needs according to the instructions received from the program stored in the memory and generates the output commands. [Pg.339]

The classical polarizing light microscope as developed 150 years ago is still the most versatile, least expensive analytical instrument in the hands of an experienced microscopist. Its limitations in terms of resolving power, depth of field, and contrast have been reduced in the last decade, in which we have witnessed a revolution in its evolution. Video microscopy has increased contrast electronically, and thereby revealed structures never before seen. With computer enhancement, unheard of resolutions are possible. There are daily developments in the X-ray, holographic, acoustic, confocal laser scanning, and scanning tunneling micro-... [Pg.68]

A variation on depth profiling that can be performed by modern scanning Auger instruments (see Sect. 2.2.6) is to program the incident electron beam to jump from one pre-selected position on a surface to each of many others in turn, with multiplexing at each position. This is called multiple point analysis. Sets of elemental maps acquired after each sputtering step or each period of continuous sputtering can be related to each other in a computer frame-store system to derive a three-dimensional analysis of a selected micro volume. [Pg.42]

Because of extreme venting conditions assumed, effective stack heights and resultant plumes from both 3- and 5-minute discharge conditions attain heights beyond the micro-meteorological conditions assumed in accepted computation models. It is therefore highly probable there will be considerably further atmospheric dispersion and diffusion of the VCM than predicted in the results shown. That is, the ground level concentration can be expected to be considerably lower than the values shown in Table 6. [Pg.361]

Finiteness is the basic assumption a finite total volume of space-time and a finite amount of information in a finite volume of space-time. We require universality, of course, since we know that without it nothing much of interest can happen. We can also take a strong cue from our own universe, which allows us to build universal computers. If the underlying micro-physics was not universal we would not be able to do this. Reversibility is desirable because it ensures a strict conservation of information and can be used to create systems that conserve various quantities such as energy and angular momentum despite underlying anisotropies. [Pg.666]

As boiling in micro-channel heat sinks is an attractive method for cooling computer CPUs and other high-heat flux devices (such as laser diodes), it is of crucial importance to accurately predict the critical heat flux (CHF) in the small-diameter channels. Critical heat flux or burnout is a limiting value for safe operation of heat dis-... [Pg.57]

Two-dimensional compressible momentum and energy equations were solved by Asako and Toriyama (2005) to obtain the heat transfer characteristics of gaseous flows in parallel-plate micro-channels. The problem is modeled as a parallel-plate channel, as shown in Fig. 4.19, with a chamber at the stagnation temperature Tstg and the stagnation pressure T stg attached to its upstream section. The flow is assumed to be steady, two-dimensional, and laminar. The fluid is assumed to be an ideal gas. The computations were performed to obtain the adiabatic wall temperature and also to obtain the total temperature of channels with the isothermal walls. The governing equations can be expressed as... [Pg.180]

A variety of studies can be found in the literature for the solution of the convection heat transfer problem in micro-channels. Some of the analytical methods are very powerful, computationally very fast, and provide highly accurate results. Usually, their application is shown only for those channels and thermal boundary conditions for which solutions already exist, such as circular tube and parallel plates for constant heat flux or constant temperature thermal boundary conditions. The majority of experimental investigations are carried out under other thermal boundary conditions (e.g., experiments in rectangular and trapezoidal channels were conducted with heating only the bottom and/or the top of the channel). These experiments should be compared to solutions obtained for a given channel geometry at the same thermal boundary conditions. Results obtained in devices that are built up from a number of parallel micro-channels should account for heat flux and temperature distribution not only due to heat conduction in the streamwise direction but also conduction across the experimental set-up, and new computational models should be elaborated to compare the measurements with theory. [Pg.187]

Using the properties of water Li and Cheng (2004) computed from the classical kinetics of nucleation the homogeneous nucleation temperature and the critical nu-cleation radius ra. The values are 7s,b = 303.7 °C and r nt = 3.5 nm. However, the nucleation temperatures of water in heat transfer experiments in micro-channels carried out by Qu and Mudawar (2002), and Hetsroni et al. (2002b, 2003, 2005) were considerably less that the homogeneous nucleation temperature of 7s,b = 303.7 °C. The nucleation temperature of a liquid may be considerably decreased because of the following effects dissolved gas in liquid, existence of corners in a micro-channel, surface roughness. [Pg.270]

In contrast,Chapter 11 looks at the very recent introduction of computer-based multimedia technologies into chemical education as a way of forging macro/sub-micro/symbolic links. Chiu and Wu discuss the value of such approaches as, respectively, a modelling tool, a learning tool, an assessment tool and an instructional tool. Their thesis is given added weight by the inclusion of results from classroom development and evaluation projects. [Pg.193]

The solid-liquid two-phase flow is widely applied in modern industry, such as chemical-mechanical polish (CMP), chemical engineering, medical engineering, bioengineering, and so on [80,81]. Many research works have been made focusing on the heat transfer or transportation of particles in the micro scale [82-88], In many applications, e.g., in CMP process of computer chips and computer hard disk, the size of solid particles in the two-phase flow becomes down to tens of nanometres from the micrometer scale, and a study on two-phase flow containing nano-particles is a new area apart from the classic hydrodynamics and traditional two-phase flow research. In such an area, the forces between particles and liquid are in micro or even to nano-Newton scale, which is far away from that in the traditional solid-liquid two-phase flow. [Pg.26]

In order to investigate the friction properties of lubricant film in TFL, an apparatus with a floating device was developed by Shen et al. as shown in Fig. 17 [48]. The steel ball is fixed so that it does not roll in the experiment and a pure sliding has been kept. The measuring system of micro-friction force is composed of a straining force sensor with a resolution of 5 yu,N, a dynamic electric resistance strain gage, an AD data-collecting card, and a computer. [Pg.43]


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See also in sourсe #XX -- [ Pg.167 ]




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