Equipment specification vibration

The electronic absorption spectra of complex molecules at elevated temperatures in condensed matter are generally very broad and virtually featureless. In contrast, vibrational spectra of complex molecules, even in room-temperature liquids, can display sharp, well-defined peaks, many of which can be assigned to specific vibrational modes. The inverse of the line width sets a time scale for the dynamics associated with a transition. The relatively narrow line widths associated with many vibrational transitions make it possible to use pulse durations with correspondingly narrow bandwidths to extract information. For a vibration with sufficiently large anharmonicity or a sufficiently narrow absorption line, the system behaves as a two-level transition coupled to its environment. In this respect, time domain vibrational spectroscopy of internal molecular modes is more akin to NMR than to electronic spectroscopy. The potential has already been demonstrated, as described in some of the chapters in this book, to perform pulse sequences that are, in many respects, analogous to those used in NMR. Commercial equipment is available that can produce the necessary infrared (IR) pulses for such experiments, and the equipment is rapidly becoming less expensive, more compact, and more reliable. It is possible, even likely, that coherent IR pulse-sequence vibrational spectrometers will... 

Engineers and designers should select equipment for installation which has low vibration and noise characteristics. They can require permissible maximum noise levels in specifications for new equipment. They can determine whether an operation, process, or piece of equipment that is noisy can be avoided or eliminated by use of a quieter one. Equipment that might vibrate should be mounted on firm, solid foundations. If equipment vibrates, they can determine whether or not its characteristics can be changed by use of devices such as dynamic dampers, rubber or plastic bumpers, flexible mountings and couplings, or resilient flooring. Where vibrations of fixed equipment cannot be eliminated, mount the equipment on vibration isolators to prevent transmission of motion. 

Surge is a phenomenon that occurs at conditions of low flow in centrifugal gas movers. All manufacturers include in their equipment specification a minimum allowable flow. At low flow, the dynamics of the piping system and the operating curve of the gas mover can be out of balance, causing pressure pulses and equipment vibrations, known as "surge." The vibration is translated to the thrust system and will ultimately destroy the equipment if surging is not stopped. 

The mechanical performance of equipment is likely to deteriorate with use due to wear, corrosion, erosion, vibration, contamination and fracture, which may lead to failure. Since this would threaten a typical production objective of meeting quality and quantity specifications, maintenance engineering provide a service which helps to safely achieve the production objective. 

Hydro projects, dams, bridges, naval equipment and any installations that aie prone to continuous shocks and vibrations also require their primary and secondary systems to have a better design and operational ability to withstand seismic effects or other ground/surface vibrations. No specific tests are presently prescribed for such applications. But response spectra can be established even for such locations and the primary and secondary systems analysed mathematically or laboratory tested. 

Accuracy of data The microprocessor should be capable of automatically acquiring accurate, repeatable data from equipment included in the program. The elimination of user input on filter settings, bandwidths and other measurement parameters would greatly improve the accuracy of acquired data. The specific requirements that determine data accuracy will vary depending on the type of data. For example, a vibration instrument should be able to average... 

The first method required to monitor the operating condition of plant equipment is to trend the relative condition over time. Most of the microprocessor-based systems will provide the means of automatically storing and recalling vibration and process parameters trend data for analysis or hard copies for reports. They will also automatically prepare and print numerous reports that quantify the operating condition at a specific point in time. A few will automatically print trend reports that quantify the change over a selected time frame. All of this is great, but what does it mean ... 

ISO 3597-2 2003 Textile-glass-reinforced plastics - Determination of mechanical properties on rods made of roving-reinforced resin - Part 2 Determination of flexural strength ISO 5893 2002 Rubber and plastics test equipment - Tensile, flexural and compression types (constant rate of traverse) - Specification ISO 6721-3 1995 Plastics - Determination of dynamic mechanical properties - Part 3 Flexural vibration - Resonance-curve method... 

Important mechanical integrity concerns, such as the manufacturers recommendations and lubrication programs, need very specific treatment depending upon the equipment and the service. Although this subject is beyond the scope of this chapter and will not be addressed, we will examine an in-house vibration program and briefly review the use of thermography. 

Some other factors that potentially could cause problems are not specific for a certain apparatus. These general factors include vibrations, variations in agitation rate, impurities due to poor cleaning or to trace amounts of metals from dissolution equipment, variations in dissolution fluid components and poor quality of dissolution media components. Another factor relevant for lipophilic compounds is migration of the drug substance into fillers and plastic material. 

The ability of both pulsed and cw infrared lasers to induce chemical reactions is well known. CO2 lasers are now common equipment in many laboratories. The infrared laser-induced process studied most extensively is multiplephoton excitation of molecules (using megawatt COj laser radiation) to high vibrational states from which reaction, usually dissociation, may occur. This field is the subject of intense effort by many research groups, and a number of excellent review articles have been written about multiplephoton excitation. At lower laser intensities it is possible to prepare molecules in specific initial vibrational states below the dissociation threshold and to study their subsequent bimolecular and unimolecular (isomerization) reactions. In this chapter we shall restrict ourselves to considering only the results of low-level vibrational excitation on chemical reactions. 

In each installation requirements of power, insulation to motion and temperature, and air intake and instrument operation needed specific consideration. Power was usually supplied by a 60-cycle, 110-V gasoline generator except in the aircraft where the 24-V aircraft battery was used. Venturi effects while sampling in motion were controlled by attaching an air baffle at the intake. Temperature stability was achieved by the use of insulation material, and the equipment was carefully mounted on an independent spring suspension to protect it from vibrations. 

Spectroscopic methods can provide fast, non-destructive analytical measurements that can replace conventional analytical methods in many cases. The non-destructive nature of optical measurements makes them very attractive for stability testing. In the future, spectroscopic methods will be increasingly used for pharmaceutical stability analysis. This chapter will focus on quantitative analysis of pharmaceutical products. The second section of the chapter will provide an overview of basic vibrational spectroscopy and modern spectroscopic technology. The third section of this chapter is an introduction to multivariate analysis (MVA) and chemometrics. MVA is essential for the quantitative analysis of NIR and in many cases Raman spectral data. Growth in MVA has been aided by the availability of high quality software and powerful personal computers. Section 11.4 is a review of the qualification of NIR and Raman spectrometers. The criteria for NIR and Raman equipment qualification are described in USP chapters <1119> and < 1120>. The relevant highlights of the new USP chapter on analytical instrument qualification <1058> are also covered. Section 11.5 is a discussion of method validation for quantitative analytical methods based on multivariate statistics. Based on the USP chapter for NIR <1119>, the discussion of method validation for chemometric-based methods is also appropriate for Raman spectroscopy. The criteria for these MVA-based methods are the same as traditional analytical methods accuracy, precision, linearity, specificity, and robustness however, the ways they are described and evaluated can be different. 

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