MACS technique

Amsden AA, Harlow FH (1970) A Simplified MAC Technique for Incompressible Fluid Flow Calculations. J Comput Phys 6 322-325... 

Particularly, immobilized-metal affinity chromatography (IMAC) is a separation technique that uses covalently bound chelating compounds on solid chromatographic supports to chelate metal ions, which serve as affinity ligands for various proteins, making use of coordinative binding of some amino acid residues exposed on the surface. Most commonly used are Cu(II), Ni(II), Zn(II), Co(II), and Fe(III) transition-metal ions, which are electron-pair acceptors and can be considered as Lewis acids. MAC technique can be used to separate proteins and peptides, with exposed histidine residues, which are primarily responsible for binding to immobilized metal ions. 

Figure 20.8 NMR investigation of phenyi-functionaiized tempiated siiica thin fiim using the MACS technique (a) MACS NMR spectrum and (b) DQ MACS NMR spectrum.

Modification techniques for activated carhon were used to increase the removal capacity by surface adsorption and to improve the selectivity to volatile organic compounds (VOCs). Modified activated carbons (MACs) were prepared by modifying the purified activated carbon with various acids or bases. The effects of adsorption capacity and modified contents on the textural properties of the MACs were investigated. Furthermore, VOC adsorption and desorption experiments were carried out to determine the relationship between the adsorption capacity and the chemical properties of the adsorbents. High adsorption capacity for the selected VOCs was obtained over lwt%-H3P04/AC (lwt%-PA/AC). As a result, MAC was found to be very effective for VOC removal by adsorption with the potential for repeated use through desorption by simple heat treatment. 

These compounds have been the subject of several theoretical [7,11,13,20)] and experimental[21] studies. Ward and Elliott [20] measured the dynamic y hyperpolarizability of butadiene and hexatriene in the vapour phase by means of the dc-SHG technique. Waite and Papadopoulos[7,ll] computed static y values, using a Mac Weeny type Coupled Hartree-Fock Perturbation Theory (CHFPT) in the CNDO approximation, and an extended basis set. Kurtz [15] evaluated by means of a finite perturbation technique at the MNDO level [17] and using the AMI [22] and PM3[23] parametrizations, the mean y values of a series of polyenes containing from 2 to 11 unit cells. At the ab initio level, Hurst et al. [13] and Chopra et al. [20] studied basis sets effects on and y. It appeared that diffuse orbitals must be included in the basis set in order to describe correctly the external part of the molecules which is the most sensitive to the electrical perturbation and to ensure the obtention of accurate values of the calculated properties. 

The use of the diphosphine PHANEPHOS (see Scheme 1.24) permitted Bar-gon, Brown and colleagues to detect and characterize a dihydrido intermediate in the hydrogenation of the enamide MAC by a rhodium-based catalyst The PH IP NMR technique was employed, and showed one of the hydrogen atoms to be agostic between the rhodium center and the /1-carbon of the substrate [85]. By using the same diphosphine and technique it was also possible to detect two diastereomers of the dihydride depicted in Scheme 1.25, which may also be detected using conventional NMR measurements [86]. 

In this chapter, the fundamentals and the most common methods and techniques for the synthesis, processing, characterization, and modification of mac-romolecular materials are described briefly, as an introduction to the special Chaps. 3,4, and 5. The main emphasis is on the description of methods and techniques used in laboratories, but some examples from industrial practice are also mentioned. 

ANL claims the technology is promising because radionuclides are separated from waste streams by a simple, compact, cost-effective process that does not produce large secondary waste streams. The MACS process is intended to reduce the complexity of equipment when compared to solvent extraction and ion exchange techniques, and to facilitate scale-up due to the systems inherent simplicity. 

Until the end of the sixties enzyme products such as the detergent proteases were just powder products. Today very few powdered-enzyme products remain. All detergent enzyme products from the larger enzyme suppliers arc either hquid formulations or granulated and further protected by coatings. Today formulation techniques really have become a science with MAC-values in production facilities of 10-100 nanogram/m air. It is further recommended that the use of such safe enzyme products shall be planned such that the liquid enzyme product is not spilled and allowed to diy and aerosol formation shall be prevented. With these simple rules in mind, industrial enzymes arc very safe. 

Halothane, isoflurane, and enflurane have similar depressant effects on the EEG up to doses of 1-1.5 MAC. At higher doses, the cerebral irritant effects of enflurane may lead to development of a spike-and-wave pattern and mild generalized muscle twitching (ie, myoclonic activity). However, this seizure-like activity has not been found to have any adverse clinical consequences. Seizure-like EEG activity has also been described after sevoflurane, but not desflurane. Although nitrous oxide has a much lower anesthetic potency than the volatile agents, it does possess both analgesic and amnesic properties when used alone or in combination with other agents as part of a balanced anesthesia technique. 

For those substances for which ingestion may cause adverse health effects, the objective limit was generally set at the detection limit obtainable by a laboratory of good standing by using conventional analytical techniques. For aesthetic parameters, the objective concentration was rather vaguely described as being less than the MAC. 

Magnetic AC atomic force microscopy (MAC Mode AFM) has proved to be a powerful surface analysis technique to investigate the interfacial and conformational properties of biological samples softly bound to the electrode surface and can be used as an important tool to characterize DNA-electrochemical biosensor surfaces [25,27],... 

Rohm and Haas uses Multiple-Cause, Systems-Oriented Incident Investigation techniques (MCSOII), or mac-soy. It is a direct adaptation of the Fault Tree Analysis logic and the Deming Principles of Systems and Quality. [10] The method was developed to improve the overall quality of investigations, to increase the uniformity of investigation made by various teams, and improve the usefulness of the proposed corrective actions. The quality of the mac-soy or MCSOII investigation is improved because the method [10]... 

Model predictive control (MPC) has become widely known as dynamic matrix control (DMC) and model algorithmic control (MAC). A review of the origins of this class of techniques and their theoretical foundations is provided by Garcia et al. [10]. Many complex applications were reported at the recent IFAC Workshop [11]. 

Welch, J. E., Harlow, F. H., Shannon, J. P, and Daly, B. J., The MAC Method A Computing Technique for Solving Viscous Incompressible Transient Fluid Flow Problems Involving Free Surfaces. Los Alamos Scientific Laboratory Report LA-3425,1965. 

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