Search results for "PLASMA"
showing 10 items of 4043 documents
Excitation and detection geometries for Fourier-transform mass spectometry
1994
A short overview of current excitation and detection techniques for Fourier-transform mass spectrometry and related ion cyclotron resonance experiments is given, and some ideas are discussed which may lead to new developments.
First Fourier-transform ion cyclotron resonance signals of very highly charged atomic ions
1994
We report on the first application of Fourier-transform ion cyclotron resonance mass spectrometry to the very highly charged ions produced in the high-energy electron beam ion trap (SuperEBIT) at the Lawrence Livermore National Laboratory. Initial results are described, and spectra are presented from ions as highly charged as Cs53+.
Spatial separation of atomic states in a laser cooled ion crystal
1999
A laser cooled ion crystal containing several hundred Ca+ ions has been stored in a linear Paul trap. Cooling is provided by a red detund laser at the 4S1/2−4P1/2 resonance transition. A second laser serves for repumping of those ions which decay from the excited 4P1/2 level to the metastable 3D3/2 state. The ions can be additionally excited by a third laser to a long lived metastable 3D5/2 energy level which decouples them from the cooling laser radiation. The light pressure acting upon the laser cooled ions pushes them into the direction of the laser beam. The ions in the metastable 3D5/2 state, however, do not experience any light pressure force and diffuse to the crystal side which poin…
Quantification of growth factors by using a new system for obtaining platelet-rich plasma
2010
Objective: To verify the performance of a new method for obtaining platelet-rich plasma, while avoiding contami- nation of the sample during its processing. Study Design: Twenty healthy patients were selected, from whom 21 ml of blood was etracted. �e then pro- Design: Twenty healthy patients were selected, from whom 21 ml of blood was etracted. �e then pro- esign: Twenty healthy patients were selected, from whom 21 ml of blood was etracted. �e then pro- ceeded to study the platelets and growth factors in basal blood after centrifuging the sample by using a new closed system for obtaining platelet-rich plasma (PRP). Results: After centrifuging the blood sample, double the amount of platelet…
Photobinding of Tiaprofenic Acid and Subprofen to Proteins and Cells: A Combined Study Using Radiolabeling, Antibodies and Laser Flash Photolysis of …
1998
Drug photoallergy is a matter of current concern. It involves the formation of drug-protein photoadducts (photoantigens) that may ultimately trigger an immunological response. Tyrosine residues appear to be key binding sites in proteins. The present work has investigated the photobinding of tiaprofenic and (TPA) and the closely related isomer suprofen (SUP) to proteins and cells by means of radioactive labeling and drug-directed antibodies. To ascertain whether preassociation with the protein may play a role in photoreactivity, two model bichromophoric compounds (TPA-Tyr and SUP-Tyr) have been prepared and studied by laser flash photolysis. The results of this work show that (a) TPA and SUP…
Effect of operation conditions of the drop-on-demand aerosol generator on aerosol characteristics: Pseudo-cinematographic and plasma mass spectrometr…
2014
Abstract The recently presented drop-on-demand (DOD) aerosol generator overcomes some of the drawbacks of pneumatic nebulization, as its aerosol is no longer generated by gas–liquid interaction. In the current study, an advanced imaging technique is presented, based on a CCD camera equipped with magnifying telecentric optics to allow for fast, automated and precise aerosol characterization as well as fundamental studies on the droplet generation processes by means of pseudo-cinematography. The DOD aerosol generator is thoroughly characterized regarding its droplet size distribution, which shows few distinct populations rather than a continuous distribution. Other important figures, such as …
The importance of incorporating a waste detoxification step in analytical methodologies
2015
The introduction of a waste detoxification step in the analytical process was highlighted using, as example, the determination of copper in pesticide formulations using electrogravimetry, flame atomic absorption spectroscopy and inductively coupled plasma optical emission spectroscopy. This quantitative study showed the improvement of the previously mentioned analytical methods, from a green perspective, after addition of electrodeposition or neutralization steps to the analytical process. Based on this, the application of the eco-scale and the Green Certificate to the evaluation of these methodologies allows the method to be moved from the B and C classes to the A class.
Recent advances in on-line solid-phase pre-concentration for inductively-coupled plasma techniques for determination of mineral elements
2012
Abstract We provide a critical survey on recent progress in on-line solid-phase pre-concentration for inductively-coupled plasma (ICP)-based techniques for trace-level determination of metals. We highlight some of the useful solid-phase materials suitable for on-line separation and enrichment prior to ICP determination. We discuss different applications of the methods developed along with their analytical figures of merit. Finally, we sketch out future prospects in this field.
Determination of trace elements in gluten-free food for celiac people by ICP-MS
2014
Abstract This paper is the first analytical approach to the study of twenty heavy metals in the gluten-free foods for celiac people. Only the ICP-MS technique was used. One of the advantages about the use of ICP-MS for this characterization is the high sensitivity that improved the limits of quantification levels for some elements that are present at low quantities in some samples. The concentration values of As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, V and Zn in seventeen gluten-free food samples are reported. The highest arsenic and molybdenum levels were measured in Rice noodle from China (0.088 and 0.47 mg kg − 1 , respectively). The highest concentrations of some metal…
"Sweet Chemistry": a Green Way for Obtaining Selenium Nanoparticles Active against Cancer Cells
2017
We present an environment friendly synthesis of selenium nanoparticles and the study of their cytotoxic activity against uterine sarcoma cancer and fibroblasts cells. Amorphous selenium (a-SeNPs) and trigonal selenium (t-SeNPs) were synthesized using D-fructose as the reducing agent and characterized by high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction analysis (XRD), inductively coupled plasma optical emission spectrometry (ICP OES), dynamic light scattering (DLS) to obtain zeta potential values and cyclic voltammetry (CV). Particularly, a-SeNPs presented high toxicity toward the resistant cancer cell line MES-SA/…