Analytical Instrument Documents

Field Desorption (FD) is a technique that ionizes analytes by electron tunneling from the analyte molecules to a solid surface (emitter) in a high electric field. The sample is applied directly onto the emitter and heated by applying an electric current through the emitter for desorption and ionization. FD has been used for the analysis of nonvolatile compounds, synthetic polymers, etc., as a soft ionization method to produce molecular ions with little or no fragmentations. As a result, the average molecular weight of a sample can be calculated directly from the masses (or “m/z”) and intensities for all of the ions observed in the FD mass spectrum. Furthermore, by applying group-type analysis, the components can be classified into types based on their functional groups and/or unsaturations. Average molecular weight, polydispersity index, or relative abundance of each type can also be obtained. In this work, new and used rotary vacuum pump (RP hereafter) oils were analyzed by FD. Afterwards, the change in their compositions was determined by performing group-type analysis on the resulting mass spectra.

Among the various methods used for characterizing plastics, pyrolysis (Py) GC/MS and thermal desorption (TD) GC/MS are widely used for both qualitative and quantitative analyses. These are simple techniques that provide detailed information about the samples. In this application note, we report the analysis of additives in plastic by using a thermal desorption system and a JEOL JMS-T100GCV "AccuTOF GCv" GC-TOFMS. Identification of the analytes was accomplished by library search and accurate mass measurement. Additionally, isotope cluster pattern matching was performed using the "Mass Spec Tools™" software to help identify an unknown compound that was present in the sample.

Lithium ion secondary batteries using spinel-type lithium titanium oxide (LTO) as the negative electrode material are excellent in safety and cycle characteristics due to their chemical stability, and have already been put into practical use.

The ESR Spectrometer JES-X3 series has an improved low-noise Gunn oscillator, providing a 30% improvement in sensitivity compared to previous models. ESR is the only instrument for directly detecting paramagnetic species. This supports a variety of applications in research, development, inspection and evaluation.

In comparison with the UltraCOOL probe, SuperCOOL probe represents a cryogenic probe with high sensitivity at lower cost and power consumption. Thermal noise reduction due to new designed cooling system greatly enhances the sensitivity of NMR measurement.

It is often difficult to unambiguously determine structures of molecules, which have many non-protonated carbon atoms. Because such compounds contain quaternary carbons, lack protons and bonding to quaternary carbons each other, HMBC (Heteronuclear Multiple Bond Correlation) experiment cannot provide long-range 1H-13C connectivity. Therefore, INADEQUATE (Incredible Natural Abundance DoublE QUAntum Transfer Experiment), which is 13C-13C correlation experiment at natural 13C abundance, represents a powerful tool for proton-diluted compounds.

Here, we combine ED and solid-state NMR through the first principle quantum computation with the NMR crystallography approach for crystalline structure solution. The method, electron and NMR nano-crystallography, can be applied to nano- to micro-crystals even for mixture samples.

Solid state NMR is a powerful tool to obtain information in the crystalline state which would be lost in the solution state.

The low oral bioavailability of a drug due to its poor aqueous solubility is a major challenge for pharmaceutical development. Solid dispersion (SD), where the amorphous drug is dispersed into the polymer matrix, is one of the useful approaches to improve the aqueous solubility. However, thermodynamically unstable nature of an amorphous drug increases its susceptibility to recrystallize upon storage, which, in turn, reduces its solubility and dissolution. Therefore, design of thermodynamically stable SD is required.

15N NMR is widely used because of the importance of nitrogen in chemistry, materials, biology, environment, etc. However, very low abundance of 15N (<0.4%) results in poor sensitivity and thus makes observation time-consuming. On the other hand, the rest of nitrogen atoms are also NMR sensitive nucleus of 14N. Despite the high abundance of 14N (>99%), it's application is rather limited due to the huge quadrupolar interactions and its spin quantum number I = 1.