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Resolution checking

In addition, a BASIC program reformats the report into a form which is directly sent to the submitter (Figure 2). FORTRAN programs can also be used to reformat the data or perform other post-run analysis of the data, such as (a) column resolution checks, and (b) secondary standard analysis. [Pg.132]

Standard reference material (SRM) for wavelength accuracy, stray light, resolution check, and photometric accuracy can be purchased from NIST. Certified reference materials (CRMs) which are traceable to NIST and recertification services can be purchased from instrument manufacturers and commercial vendors [12]. The cost of neutral-density filters and prefabricated standard solutions in sealed cuvettes can be substantial. When purchasing performance verification standards from a secondary supplier other than a national standard organizations such as NIST in the United States and National Physical Laboratory (NPL) in the United Kingdom, make sure that the traceability of the standards are available in the certificates. The traceability establishes the relationship of individual results to the national standard through an unbroken chain of comparisons. [Pg.170]

Once the spectrometer has been set up, a maintenance schedule should be defined so that various adjustments are checked on a regular basis at appropriate intervals. For example, the DC offset and pole-zero settings might be checked on a quarterly basis but the energy calibration checked on a daily basis. The ANSI document recommends efficiency and resolution checks on a daily or weekly basis. An efficiency check on a daily basis does seem rather enthusiastic, but in such matters, it is wise to err on the side of too frequent rather than seldom. If efficiency is monitored simply by measuring a check sample, there should be little problem. [Pg.298]

In general, the performance of a radioscopic system should always be checked via test pieces with natural flaws. To ensure an additional comparability, standardized image quality indicators have to be used to control the essential image quality parameters such as spatial resolution (unsharpness) and contrast sensitivity. [Pg.438]

The evaluation of the deconvolution results show that time resolution is better or equal to 1 with the chosen processing time unit of 0.08 microseconds (respectively a rate of 12.5 MHz). First signals processed conservatively have been acquired with a samplerate of 12.5 MHz. A Fourier analysis shows that the signals spectras do not have energy above 2.0 MHz. This means that a sampling rate of 4.0 MHz would have done the job as well. Due to the time base of the ADC an experimental check with a sample rate of 5.25 MHz has been carried out successfully. [Pg.843]

To enable an atomic interpretation of the AFM experiments, we have developed a molecular dynamics technique to simulate these experiments [49], Prom such force simulations rupture models at atomic resolution were derived and checked by comparisons of the computed rupture forces with the experimental ones. In order to facilitate such checks, the simulations have been set up to resemble the AFM experiment in as many details as possible (Fig. 4, bottom) the protein-ligand complex was simulated in atomic detail starting from the crystal structure, water solvent was included within the simulation system to account for solvation effects, the protein was held in place by keeping its center of mass fixed (so that internal motions were not hindered), the cantilever was simulated by use of a harmonic spring potential and, finally, the simulated cantilever was connected to the particular atom of the ligand, to which in the AFM experiment the linker molecule was connected. [Pg.86]

In order to select the instmmental conditions for carrying out the ATR measurements several parameters including the number of accumulated scans per spectra or nominal resolution were tested. To avoid the crosscontamination and to establish an appropriate strategy for cleaning the ATR cell between samples, several procedures were tested using background and blank controls. Moreover, the possible sample sedimentation on the ATR plate cell due to the complexity of the sample matrix during the spectra acquisition was also checked. [Pg.142]

KS Wilson, Z Dauter, VS Lamsm, M Walsh, S Wodak, J Richelle, J Pontius, A Vagume, RWW Hooft, C Sander, G Vriend, JM Thornton, RA Laskowski, MW MacArthur, EJ Dodson, G Murshudov, TJ Oldfield, R Kaptem, JAC Rullman. Who checks the checkers Four validation tools applied to eight atomic resolution structures. J Mol Biol 276 417-436, 1998. [Pg.310]

A special mention is in order of high-resolution electron microscopy (HREM), a variant that permits columns of atoms normal to the specimen surface to be imaged the resolution is better than an atomic diameter, but the nature of the image is not safely interpretable without the use of computer simulation of images to check whether the assumed interpretation matches what is actually seen. Solid-state chemists studying complex, non-stoichiometric oxides found this image simulation approach essential for their work. The technique has proved immensely powerful, especially with respect to the many types of defect that are found in microstructures. [Pg.221]

Gel filtration is very suitable for the purity check of protein preparations, especially if these have been purified by adsorptive techniques. It can be expected that high-resolution gel filtration columns will easily separate dimeric forms from monomeric forms to reveal heterogeneities of the preparations. However, a size difference of less than 20% will not result in total resolution of the peaks (although the chromatogram may be used for a qualitative judgment of the... [Pg.70]

The main problem in Eas0 vs. correlations is that the two experimental quantities are as a rule measured in different laboratories with different techniques. In view of the sensitivity of both parameters to the surface state of the metal, their uncertainties can in principle result of the same order of magnitude as AX between two metals. On the other hand, it is rare that the same laboratory is equipped for measuring both single-crystal face is not followed by a check of its perfection by means of appropriate spectroscopic techniques. In these cases we actually have nominal single-crystal faces. This is probably the reason for the observation of some discrepancies between differently prepared samples with the same nominal surface structure. Fortunately, there have been a few cases in which both Ea=0 and 0 have been measured in the same laboratory these will be examined later. Such measurements have enabled the resolution of controversies that have long persisted because of the basic criticism of Eazm0 vs. 0 plots. [Pg.157]

Check for potential conflicts in the specification of the goal state, and provide resolution for its consistent definition. [Pg.70]

Monitor the patient for resolution of hematuria after each successive therapeutic intervention. Frequency of monitoring is based on the severity of hemorrhaging. Monitor urinary output and serum chemistries (including sodium, potassium, chloride, blood urea nitrogen, and serum creatinine) daily for renal dysfunction. Check the CBC at least daily to monitor hemoglobin and platelet count. [Pg.1482]

Most mass spectrometers will resolve ions with unit resolution up to at least 2000 Da, and so monoisotopic atomic masses are used in these cases. Above 2000 Da, the resolution should be checked and, if it is insufficient to resolve adjacent isotopes, then average atomic masses can be used in calculations. [Pg.355]


See other pages where Resolution checking is mentioned: [Pg.181]    [Pg.532]    [Pg.103]    [Pg.325]    [Pg.112]    [Pg.261]    [Pg.384]    [Pg.181]    [Pg.532]    [Pg.103]    [Pg.325]    [Pg.112]    [Pg.261]    [Pg.384]    [Pg.401]    [Pg.439]    [Pg.480]    [Pg.493]    [Pg.277]    [Pg.453]    [Pg.195]    [Pg.118]    [Pg.89]    [Pg.30]    [Pg.234]    [Pg.377]    [Pg.615]    [Pg.47]    [Pg.113]    [Pg.302]    [Pg.180]    [Pg.389]    [Pg.496]    [Pg.96]    [Pg.116]    [Pg.662]    [Pg.179]    [Pg.191]    [Pg.242]    [Pg.313]    [Pg.500]    [Pg.22]   


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