SPICE tools

Applications. The most ubiquitous use of infrared spectrometry is chemical identification. It has long been an important tool for studying newly synthesi2ed compounds in the research lab, but industrial identification uses cover an even wider range. In many industries ir spectrometry is used to assay feedstocks (qv). In the flavors (see Flavors and spices), fragrances (see Perfumes), and cosmetics (qv) industries, it can be used not only for gross identification of feedstocks, but for determining specific sources. The spectra of essential oils (see Oils, essential), essences, and other natural products vary with the season and source. Adulteration and dilution can also be identified. 

Since its introduction in 1971, SPICE (Simulation Program with Integrated Circuit Emphasis) has become the most popular analog simulation tool in use today. In the last 15 years, we have seen explosive growth in the use of SPICE, with the addition of Berkeley SPICE 3 enhancements, and support for C code model and mixed-mode simulation using XSPICE (Cox et al. 1992, Kielkowski 1994).We have also seen many new companies emerge as developers of SPICE-based simulation tools, most of which are currently available for the PC platform. 

Each vendor of SPICE simulation software has added features such as Monte Carlo analysis, schematic entry, and post simulation waveform processing, as well as extensive model libraries. In most cases, the manufacturers have modified the algorithms for controlling convergence and have added new parameters or syntax for component models. As a result, each electronic design automaton (EDA) tool vendor has the basic Berkeley SPICE 2 features and a unique set of capabilities and performance enhancements. 

The purpose of this book is to showcase the ability of SPICE, via the simulation tools of several EDA vendors, to accurately predict the behavior of electronic circuitry. 

Still, there are limitations to the capabilities of SPICE and similar circuit simulators. While the sophistication of simulation increases, the hardware breadboard will still remain a necessary step in the design process. This book will aid the engineer in using SPICE simulation as a very powerful tool in the design process. 

In 1983, SPICE 2G.6 was released and remained the industry standard for many years. Motivated by the increased use of UNIX workstations and superior programming tools, SPICE 2 was converted into the C programming language and released as SPICE 3. Although SPICE 3 is not entirely backward compatible with SPICE 2, the new features far outweigh this drawback. SPICE 3 has a technical advantage of being readily modified because it is written in C. SPICE 3 also offers more and improved device models and analysis functions. 

A major improvement in terms of usability has been the addition of a graphical waveform post processing and schematic capture tools. Waveform post processors greatly facilitate computation and documentation of simulation results. Schematic capture automates the SPICE netlist generation dramatically reducing the number of syntax errors. 

The tool flow used by EDA vendors to enhance the basic SPICE engine is roughly the same. Four separate modules are utilized (see Table 2.1). 

A text editor is also included and is an invaluable tool for viewing the generated output text files of SPICE, as well as investigating syntax errors and other subtleties of the SPICE programming language. The text output of SPICE is in an excellent format for exporting to other useful engineering tools such as Excel or MathCAD. 

Luckily, there are circuits that fill all of the power requirements listed above and more. SPICE can be an indispensable tool for designing, troubleshooting, and characterizing power conversion circuits. 

The thin small blades of a Microplane zester cut spices, such as whole nutmeg, and the peel of fruit into minuscule pieces that are perfect for incorporating into batters and frostings. The zester slices into just the top outermost layer of citrus, so the bitter white pith does not get zested. The tool is really sharp, so be especially careful with kids around. This is definitely an essential for your baking kitchen you will find Microplanes in kitchenware stores. 

Lucchesi, M.E., Chemat, F. and Smadja, J. (2004) Solvent-free microwave extraction an innovative tool for rapid extraction of essential oil from aromatic herbs and spices. The Journal of Microwave Power and Electromagnetic Energy 39(3 4), 135-1 39. 

Radiation also is an important tool in the medical treatment of cancer. However, what may be one of its most important applications, extending the storage life of foods, has been seriously delayed by public concern, in spite of extensive tests showing that irradiated foods meet all international safety standards. Currently, the United States irradiates spices for the main purpose of bug removal. 

Clove oil may be obtained from cloves by steam distillation. A number of other spices may be used for extracting other oils (9,10) whose structures are shown in Table 16-1. The essential oils are rich in one main compound and since all components are UV absorbing, the fixed wavelength detector at 254 nm is adequate for detection. Liquid chromatography is a rapid analytical tool in analyzing the essential oils. 

Once a system is represented as an equivalent circuit, additional complications can be easily taken into acconnt. For example nonlinearity can be introdnced by making a resistor value dependent on cnrrent. Numerical solution for networks of nonlinear capacitors and resistors are straightforward with standard theoretical treatment and free compntational tools (such as SPICE, Hageman [1993]) widely available. 

Methods to calculate time dependent current/voltage response for circuits whose parameters depend on voltage or current are well developed in theoretical electronics and free open source tools for numerical calculations are available, such as general electronic circuit simulator SPICE (Hageman [1993]). 

Some examples of circuit analyzers are SPICE and PSPICE. SPICE and PSPICE build mathematical models of each circuit and then perform thousands of complex calculations to predict how the circuit will respond to input signals. Most suppliers of CAD systems also offer their own adaptations of these analysis tools. 

This application describes the analysis of extracts from spices using GC-MS/MS as a highly selective tool for the quantitative trace determination of the representative ingredients of natural active spice ingredients capsaicin, piperine, thymol, and also cinnamaldehyde as a flavouring side component. 

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