Analogue recording

The infrared spectra of ammonium magnesium phosphate hexahydrate and its potassium analogue recorded at room temperature have already been studied [8] and the RT Raman spectrum of struvite has also been reported [9], In addition to that, our results of the study of the spectra of KMgP04-6H20 will be published shortly [10], To the best of our knowledge, the vibrational spectra of arsenstruvite and its deuterated analogues and also the vibrational spectra of the whole series of deuterated analogues of either of the three compounds have not been reported yet. 

An analogue record of the spectrophotometer signals, or a corresponding hard copy generated by whatever acquisition system is used, provides a most valuable documentation of the performance of the analytical system and is the best insurance policy against data loss due to computer failures (a very conunon problem in ship operation of analysers). 

C-nmr data have been recorded and assigned for a great number of hydantoin derivatives (24). As in the case of H-nmr, useful correlations between chemical shifts and electronic parameters have been found. For example, Hammett constants of substituents in the aromatic portion of the molecule correlate weU to chemical shifts of C-5 and C-a in 5-arylmethylenehydantoins (23). Comparison between C-nmr spectra of hydantoins and those of their conjugate bases has been used for the calculation of their piC values (12,25). N-nmr spectra of hydantoins and their thio analogues have been studied (26). The N -nmr chemical shifts show a linear correlation with the frequencies of the N—H stretching vibrations in the infrared spectra. 

In addition, most devices provide operator control of settings for temperature and/or response slope, isopotential point, zero or standardization, and function (pH, mV, or monovalent—bivalent cation—anion). Microprocessors are incorporated in advanced-design meters to faciHtate caHbration, calculation of measurement parameters, and automatic temperature compensation. Furthermore, pH meters are provided with output connectors for continuous readout via a strip-chart recorder and often with binary-coded decimal output for computer interconnections or connection to a printer. Although the accuracy of the measurement is not increased by the use of a recorder, the readabiHty of the displayed pH (on analogue models) can be expanded, and recording provides a permanent record and also information on response and equiHbrium times during measurement (5). 

Not in the class of digital recording storage media are video CDs with diameters of 200 and 300 mm, respectively. These are storage disks for recording the analogue signal of videos and are of air-sandwich constmction with two poly(methyl methacrylate) disks. 

IR spectroscopy has also been used in structural problems in 2- and 3-hydroxypyrido[3,4-f ]pyrazines (63JCS5156), in 8-oxopyrido[2,3-f ]pyrazine-7-acids (73MI21501) and in the pyrido[3,4-f ]quinoxaline field (74JCS(P1)1965). IR spectra were recommended for the distinction of isomeric products in the Isay reaction (Section 2.15.15.6.1) (71TH21500) UV spectra were not satisfactory. The Raman spectra of a number of 1- and 3-deazaflavin analogues have been recorded and discussed (80BBA(623)77). 

Fatty Acid Transporters. Figure 2 Quencher-based real-time fatty acid uptake assay with a fluorescently labeled FFA analogue (C1-Bodipy-C12). Predominantly protein-mediated fatty acid uptake by 3T3-L1 adipocytes (diamonds) was compared with diffusion-driven uptake by fibroblasts (squares) using the QBT Fatty Acid Uptake reagent (Molecular Devices Corp., CA, USA), which contains C1-Bodipy-C12 as substrate in conjunction with a cell impermeable quencher. Uptake kinetics was recorded using a Gemini fluorescence plate reader. Error bars indicate the standard deviations from 12 independent wells. RFU relative fluorescence units. 

Figure 2. Schematic representation of the reactor system computer-controlled pumps (PI, P2) pump controllers (fc) reactor (CSTR) reception vessel valves (S1-S4) monomer and initiator storage vessels (Tl, T2). (a) Digital input from GPC injection valve (b) analogue output from GPC (c, d) digital outputs to recorder chart drive and event marker (e, f) analogue outputs for pump set-point adjustment (g,h) reactor feeds (i) reactor output (j-m) digital outputs to reception system valves (n) manual sampling of products by GPC,...

The first successful stabilization of a silene, Me2Si=CH2 [117], in an argon matrix was achieved in experiments on the vacuum pyrolysis of 1,1-dimethylsilacyclobutane [118] (Mal tsev et al., 1976b). The IR spectra of the silene [117] and some of its deuterated analogues have been recorded... 

Phenazine leuco dyes, like their thiazine and oxazine analogues, have also found application in electrolytic recording, overhead transparencies, and Color Dry Silver. The phenazine leuco 48 is employed in electrolytic recording,17 whereas compounds 49, 50 are described as useful in thermographic and photothermographic systems.18... 

In this series of instruments for analytical electrochemistry, Philips also supplies the microprocessor-controlled PW 9527 digital conductivity meter with 16 push-buttons and on the rear an analogue output for connection to a recorder and a 25-way connector providing a two-way RS 232 serial connection (see Philips leaflet 9498 362 9326). 

For conductimetric incremental titrations, large rugged analogue conductivity meters have also become available, e.g., the Metrohm 518 conductometer (in connection with the Model 536 potentiograph its yields a rapid recording of the curve together with end-point indication) and the Philips PW 9505 analogue conductivity meter (in addition to a recorder output and an output for electrode re-platinization, there is a choice of manual or, by use of a Pt 100 resistance thermometer, automatic temperature compensation). 

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