This study presents a novel direct probe (DP) to perform electrospray ionization (ESI). The probe is constructed simply from a thin copper ring connected to a high voltage power supply, and a capillary and syringe pump are unnecessary. Approximately one microliter of the sample solution is applied directly onto the copper ring by a micropipette. Electrospray from the solution on the copper ring is induced by surface deformation by deflecting a droplet from the copper ring. The mass spectra of proteins obtained by DP-ESI are exactly the same as those from conventional ESI sources through a capillary needle. The time deemed necessary to complete an analysis is approximately 2 minutes, and sample switching is immediate. The signals of the analyte can last from 45 seconds to more than 10 minutes depending on probe design. Three different types of probes used to retain more sample solution on the probe during electrospray were designed and constructed. Moreover, cleaning the probe between different sample analysis is easy. Since a capillary is not used for sample transportation, presence of the particles in the sample solution does not interfere with the electrospray process by capillary blockage.

This work detects protonated molecular ions of highly reactive pyrolytic products--cyclopentadienylideneketene, cyclohexadienylideneketenimine, and acetylketene--using a flow pyrolyzer connected to a multiple-channel electrospray mass spectrometry. The ketene generated in the flow pyrolyzer is directly conducted into the central channel of a seven-channel electrospray ionization source by a stream of nitrogen gas. Concurrently, a methanol solution containing 0.1% trifluoroacetic acid is electrosprayed through the outside six channels. The protonated methanol ions and the charged droplets generated from the outside six electrospray channels facilitate the ionization of the neutral ketenes through ion-molecule reactions or absorption followed by protonation.

The electrical conductivity of glasses determined by TSPC agrees well with that measured by conventional ac or dc techniques. The TSPC technique is a rapid and easy method of measuring the dc conductivity over the range 10−15–10−7 (Ω cm)−1 and is especially suited for conductivities <10−12 (Ω cm)−1. Polarization at the electrodes is easily detected and avoided.

Sodium-ion motion in three sodium silicate glasses and a sodium aluminosilicate glass was investigated by the thermally stimulated polarization (TSPC) and depolarization (TSDC) current techniques. The two TSDC peaks found in the sodium silicate glasses were attributed to localized sodium-ion movement around a nonbridging oxygen ion, a type of dipolar orientational polarization, and to a longer-range sodium motion leading to interfacial polarization at the immiscible phase boundaries. The high-temperature background (HTB) current corresponded to the sodium motion for dc conductivity and diffusion. The commonly observed dc absorption current was found to be related to the two TSDC peaks.