background: the effectiveness and safety of brachytherapy treatment is mainly concerned with the calibration of sources and their traceability to internationally accepted standards. secondary standard dosimetry laboratory (ssdl) does not offer calibration of ionization chambers with gamma-ray spectrum of high dose rate source 192ir . this work has been carried out to calibrate the high dose rat...

We have investigated the capability of nanoparticle-assisted laser desorption ionization mass spectrometry (NP-LDI MS), matrix-assisted laser desorption ionization (MALDI) MS, and gas cluster ion beam secondary ion mass spectrometry (GCIB SIMS) to provide maximum information available in lipid analysis and imaging of mouse brain tissue. The use of Au nanoparticles deposited as a matrix for NP-L...

RATIONALE Mass spectrometry with atmospheric pressure ionization is the most promising method for studying the structure of natural lignin, which is the second most abundant biopolymer in nature. The goal of this study is to compare the efficiency and characteristics of different types of ionization techniques (ESI, APCI, and APPI) in the negative ion mode by the example of softwood lignin. M...

A surface acoustic wave-based sample delivery and ionization method that requires minimal to no sample pretreatment and that can operate under ambient conditions is described. This miniaturized technology enables real-time, rapid, and high-throughput analysis of trace compounds in complex mixtures, especially high ionic strength and viscous samples that can be challenging for conventional ioniz...

The paper presents a modified and universally applicable diagnostic fragment-ion-based extension strategy (DFIBES) to efficiently process the information acquired by liquid chromatography-electrospray ionization source in combination with hybrid ion trap and high-resolution time-of-flight mass spectrometry [LC-(ESI)-IT-TOF/MS], facilitating the structural determination of serial components cont...

background: in order to deliver the precise dose to the target in radiotherapy, absorbed dose to water at the reference point should be assessed. when the calibration procedure is performed for a reference dosimeter in the 60co beam of a secondary standard dosimetry laboratory (ssdl), the total uncertainty in absorbed dose to water (dw) is estimated to be approximately 1.5%. this study attempts...

Calix (4) pyrroles are macromolecules structurally related to porphyrins, they exhibit exceptional chemical and physical properties that have suggested a vast number of potential applications in host-guest chemistry. In recent years, calix (4) pyrroles have attracted a lot of attention because of their properties as binders of anions, transition metals, and neutral substrates and their new appl...

calix(6)arene hydroxamic acids (iii) are synthesised for the first time by reactingcalix(6)arene acid chloride(ii) with substituted hydroxylamines at low temperature in the presence ofsodium bicarbonate. the p-carboxycalix(6)arene(i) is obtained by an acid catalysed condensationreaction of p-hydroxybenzoic acid and formaldehyde. these calixarenes are characterised by meltingpoint, uv, ir, 1h nm...