6 research outputs found
Sensitive Determination of Cd in Small-Volume Samples by Miniaturized Liquid Drop Anode Atmospheric Pressure Glow Discharge Optical Emission Spectrometry
A novel
liquid drop anode (LDA) direct current atmospheric pressure
glow discharge (dc-APGD) system was applied for direct determination
of Cd in liquid microsamples (50 μL) by optical emission spectrometry
(OES). The microdischarge was generated in open-to-air atmosphere
between a solid pin type tungsten cathode and a liquid drop placed
on a graphite disk anode. The arrangement of the graphite disk placed
on a PTFE chip platform as well as the solid pin type cathode was
simple and robust. The limit of detection (LOD) of Cd for the developed
LDA-APGD-OES method was 0.20–0.40 μg L<sup>–1</sup>, while precision (as the relative standard deviation for the repeated
measurements) was within 2–5%. By using the liquid drop of
50 μL, the linearity range of 1–1000 μg L<sup>–1</sup> was achieved. The effect of addition of the low-molecular weight
(LMW) organic compounds, easily ionized elements (EIEs), i.e., Ca,
K, Mg, and Na, as well as the foreign ions (Al, Cu, Fe, Mn, Zn) to
the solution on the <i>in situ</i> atomization and excitation
processes occurred during operation of the LDA-APGD system, and the
response of Cd was studied. Validation of the proposed method was
demonstrated by analysis of <i>Lobster hepatopancreas</i> (TORT-2), pig kidney (ERM-BB186), and groundwater (ERM-CA615) certified
reference materials (CRMs) and recoveries of Cd from water samples
spiked with 25 μg L<sup>–1</sup> of Cd. Very good agreement
between the found and certified values of Cd in the CRMs (the recoveries
were within the range of 96.3–99.6%) indicated trueness of
the method and its reliability for determination of traces of Cd.
In the case of the spiked water samples, the recoveries obtained were
in the range from 95.2 to 99.5%
Surface recombination and space-charge-limited photocurrent-voltage (PC-V) measurements in (Cd,Mn)Te samples. Kinetics of photocurrent (PC)
Photocurrent-voltage characteristic (PC-V) is a method of determining the
critical parameter in X-ray and gamma-ray detector plates, i.e., the carrier
mobility - lifetime product, mt. We show on the (Cd,Mn)Te samples that the
measurement results depend strongly on the surface treatment and the charge
space distribution. The PC-V characteristics obtained for hv > Eg and hv ~ Eg
indicated that etching with 20% HCl caused an appearance of a significant
concentration of very shallow surface traps at the (Cd,Mn)Te sample surface.
These traps seriously changed the measurements of PC-V characteristics and PC
kinetics. We also noticed a small contribution of holes to photoconductivity in
the PC kinetics. The PC-V characteristics measurements for hv > Eg may test the
detector plate surface quality.Comment: 16 pages, 13 figure
The cosmic ray detector for the NICA collider
Multi-Purpose Detector (MPD) is a main part of a new Ion Collider fAcility (NICA) located in Dubna, Russia. To increase MPD functionality, it was proposed to add an additional muon trigger system for off-beam calibration of the MPD sub-detectors and for rejection of cosmic ray background during experiments. The system could also be very useful for astrophysical observations of cosmic showers initiated by high energy primary particles. This article describes the main goals of MCORD detector and the early stage of MCORD design, based on plastic scintillators with silicon photomultiplier photodetectors (SiPM) for scintillation readout and electronic system based on MicroTCA standard
Influence of pH and low-molecular weight organic compounds in solution on selected spectroscopic and analytical parameters of flowing liquid anode atmospheric pressure glow discharge (FLA-APGD) for the optical emission spectrometric (OES) determination of Ag, Cd, and Pb
The cosmic ray detector for the NICA collider
Multi-Purpose Detector (MPD) is a main part of a new Ion Collider fAcility (NICA) located in Dubna, Russia. To increase MPD functionality, it was proposed to add an additional muon trigger system for off-beam calibration of the MPD sub-detectors and for rejection of cosmic ray background during experiments. The system could also be very useful for astrophysical observations of cosmic showers initiated by high energy primary particles. This article describes the main goals of MCORD detector and the early stage of MCORD design, based on plastic scintillators with silicon photomultiplier photodetectors (SiPM) for scintillation readout and electronic system based on MicroTCA standard