Internal Standard an Important Analyte Use in Drug Analysis by Liquid Chromatography Mass Spectrometry- An Article

Internal standard is an external compound which is mixed with targeted analytical solution and matrix as a constant concentration and use for preparing calibration standard curve by using ratio of analyte area and internal standard area with analyte concentration and internal standard concentration. This calibration curve used for quantification of unknown concentration of anlayte of interest. This article provide necessary information about internal standard like its selection procedure, characterization, types and response factor , to all analyst who are connected with drug analysis. This article is more important and I think first article which focuses a clear idea about internal standard use in drug analysis.

THE EFFECT OF PACKAGING TYPE AND STORAGE TEMPERATURE ON THE SHORT TERM STABILITY OF ELECTROLYTIC CONDUCTIVITY REFERENCE MATERIALS

In this work, monitoring the effect of packaging type and storage temperature on the short term stability of calibration standard solution KCl 1 M were conducted. The KCl 1M were packaged in two types of packaging i.e., high-density polyethylene (HDPE) and glass bottle. The effects of packaging type and storage temperature were monitored for four weeks at 25 °C and 40 °C. The conductivity values of KCl 1 M in the HDPE and glass bottle were 111.61 mS/cm and 111.62 mS/cm, respectively. The results indicated that the KCl 1M solution at 25 °C in both HDPE and glass bottle were found to be good in short term stability and there was no significant different between the two packaging types. At temperature of 40 °C, however, short term stability of the KCl 1 M in a glass bottle was better than the HDPE bottle.

Research on the normalisation method of logging curves: taking XJ Oilfield as an example

During the long-term exploration and development of the oilfield, it is difficult to ensure that all well logging curves are measured by the same type of instrument, the same calibration standard and the same operation mode, For different wells, there must be systematic errors caused by these reasons. Therefore, in addition to environmental correction, it is necessary to standardise logging curves. In XJ oilfield, three logging companies use wireline logging and logging while drilling to complete logging, in multi-well logging interpretation. To eliminate the systematic errors of different measuring tools, to maximise the geological information reflected by logging curves, and to make logging interpretation follow the same standard as much as possible, it is necessary to standardise the logging curve in the whole oilfield. This article takes the standardisation of well 106 in XJ oilfield as an example, the standardisation of different methods was compared, the method of combining frequency histogram and mean variance is better.

A Climate Hyperspectral Infrared Radiance Product (CHIRP) Combining the AIRS and CrIS Satellite Sounding Record

A Climate Hyperspectral Infrared Radiance Product (CHIRP) is introduced combining data from the Atmospheric Infrared Sounder (AIRS) on NASA’s EOS-AQUA platform, the Cross-Track Infrared Sounder (CrIS) sounder on NASA’s SNPP platform, and continuing with CRIS sounders on the NOAA/NASA Joint Polar Satellite Series (JPSS) of polar satellites. The CHIRP product converts the parent instrument’s radiances to a common Spectral Response Function (SRF) and removes inter-satellite biases, providing a consistent inter-satellite radiance record. The CHIRP record starts in September 2002 with AIRS, followed by CrIS SNPP and the JPSS series of CrIS instruments. The CHIRP record should continue until the mid-2040’s as additional JPSS satellites are launched. These sensors, in CHIRP format, provide the climate community with a homogeneous sensor record covering much of the infrared. We give an overview of the conversion of AIRS and CrIS to CHIRP, and define the SRF for common CHIRP format. Considerable attention is paid to removing static bias offsets among these three sensors. The CrIS instrument on NASA’s SNPP satellite is used as the calibration standard. Simultaneous Nadir Overpasses (SNOs) as well as large statistical samplings of radiances from these three satellites are used to derive the instrument bias offsets and estimate the bias offset accuracy, which is ~0.03 K. In addition, possible scene-dependent calibration differences between CHIRP derived from AIRS and CHIRP derived from CrIS on the SNPP platform are presented.

Factors Affecting Measurements of IOP Using Non-Contact Eye Tonometer

The objective measurement of intraocular pressure (IOP) represents the identification of the symptoms of some diseases, e.g. glaucoma. This objective measurement can only be achieved by correct calibration of tonometers. Today, there is no uniform methodology for this calibration. Therefore, we introduce potential sources of error and try to quantify their contributions in this paper. Subsequently, a calibration standard containing an artificial cornea with similar properties to the human one should be designed.