Simulation of a Miniature Linear Ion Trap with Half-Round Rod Electrodes.

The miniaturization of ion trap mass analyzers is an important direction in the development of mass spectrometers. In this work, we proposed two models of miniaturized HreLIT with a field radius of about 2 mm based on the existing research on conventional HreLIT and other ion traps, one with ions ejection slits on one pair of electrodes only (2-slit model) and the other with the same slits on all electrodes (4-slit model). The relationship of mass resolution with and the "stretch" distance of electrodes in the ejection direction is investigated by theoretical simulations.

[Prokaryotic Expression and Immunogenicity Analysis of a Fusion Protein Containing Cell Epitopes of 2660, 2460, 3875 and 3804 Genes].

Objective: To analyse the immunogenicity of a fusion protein containing cell epitopes of genes 2660, 2460, 3875 and 3804, and to evaluate the feasibility of using it as a novel target antigen for developing multi-stage TB vaccines.

Methods: Cell epitopes of 2660, 2460, 3875 and 3804 were fused in series to form a new antigen gene (named ). Then was cloned into the prokaryotic expression vector -Blunt E1.

Printed circuit board ion trap mass analyzer: its structure and performance.

An ion trap (IT) mass analyzer can be simply built with low cost material-the printed circuit board (PCB). A printed circuit board ion trap (PCBIT) can perform ion trapping, mass analysis, and tandem mass spectrometry as a conventional ion trap mass analyzer. In a PCBIT, each PCB electrode was fabricated to specially designed patterns with several separate electric strips.

Studies on the non-covalent interactions between cyclodextrins and aryl alkanol piperazine derivatives by mass spectrometry and fluorescence spectroscopy.

The non-covalent complexes of alpha- and beta-cyclodextrins (alpha-, beta-CDs) with two aryl alkanol piperazine derivatives (Pipe I and Pipe II) have been studied by electrospray ionization mass spectrometry (ESI-MS) and fluorescence spectroscopy. The ESI-MS experimental results demonstrated that Pipe I can conjugate to beta-CD and form 1:1 or 1:2 stoichiometric non-covalent complexes, and Pipe II can only form 1:1 complexes with alpha- or beta-CD. Fluorescence spectra indicated that the fluorescence intensities of Pipe I and Pipe II can be enhanced by increasing the content of beta-CD.

Two stability islands of quadrupole mass filter near q = 0.9 created by auxiliary radio frequency voltage.

We report the numerical investigations of quadrupole mass filters concerning stability islands created by auxiliary radio frequency (RF) voltage with high and low frequencies near q = 0.9. The islands are located along the q axis near boundary value q = 0.

Ion trap array mass analyzer: structure and performance.

An ion trap array (ITA) mass analyzer--a novel ion trap mass analyzer with multiple ion trapping and analyzing channels--was designed and constructed. Its property and performance were investigated and reported in this paper. The ITA was built with several planar electrodes including two parallel printed circuit board (PCB) plates.

Formation and characterization of the (eta2-N2)Sc(H)OH and (eta1-NN)xSc(H)OH (x = 1, 2) complexes in solid argon.

Hydrido scandium hydroxide dinitrogen complexes, (eta2-N2)Sc(H)OH and (eta1-NN)xSc(H)OH (x = 1, 2), have been prepared by the reactions of laser-ablated scandium atoms with H2O/N2 mixtures in solid argon. The end-on bonded (eta1-NN)xSc(H)OH (x = 1, 2) complexes were formed spontaneously on annealing, whereas the side-bonded (eta2-N2)Sc(H)OH complex was generated on broad-band irradiation. These complexes were characterized by infrared absorption spectroscopy as well as density functional theoretical calculations.