Faraday probe measurements were taken in the near-field plume of a 6-kW Hall thruster to reduce the negative effects of facility-induced charge-exchange collisions. The results from these measurements were analyzed using a non-standard definition of the current density integration bounds that produced self-consistent beam current and beam divergence values. The measurements indicated a beam div...

1. The characteristics of benzofuroxan (benzofurazan 1-oxide, benzo-2-oxa-1,3-diazole N-oxide) that relate to its application as a reactivity probe for the study of environments of thiol groups are discussed. 2. To establish a kinetic and mechanistic basis for its use as a probe, a kinetic study of its reaction with 2-mercaptoethanol was carried out. 3. This reaction appears to proceed by a rat...

Charge carrier transport through the probe-sample junction can have substantial consequences for outcomes of electrical and electromechanical atomic-force-microscopy (AFM) measurements. For understanding physical processes under probe, we carried out conductive-AFM (C-AFM) measurements local current-voltage (I-V) curves as well their derivatives on samples a mixed ionic-electronic conductor Li1...

An indole-azadiene conjugate (1), synthesized by facile one-step condensation, behaves as a highly selective probe for detection of fluoride ion both in colorimetric and fluorometric analyses. The probe 1 shows F(-)-selective color change from colorless to yellow and appearance of green fluorescence. 1H NMR analysis and ab initio calculation reveal that the F(-)-induced colorimetric and fluorom...

A colorimetric and fluorometric dual-model probe for mercury (II) ion was developed employing fluorescein hydrazide (FH) in ethanol-HEPES solution (1:1, v/v, pH 8.0). The probe exhibited high selectivity and sensitivity for Hg detection using UV/Vis and fluorescence spectroscopy. Addition of Hg caused a visual color change from colorless to coloured and a fluorescence change from colorless to b...

Ca(2+) is a fundamental metal ion for physiological functioning. Therefore, molecular probes for Ca(2+) analysis are required. Recently, a hyperpolarized NMR probe has emerged as a promising tool. Here, we report a new design of a hyperpolarized NMR probe for Ca(2+), which showed a large chemical shift change upon binding to Ca(2+) and was applied for Ca(2+) sensing in a hyperpolarized state.

Voltage-gated K channels associate with multiple regulatory proteins to form complexes with diverse gating properties and pharmacological sensitivities. Small molecules which activate or inhibit channel function are valuable tools for dissecting the assembly and function of these macromolecular complexes. My thesis focuses on the discovery and use of small molecules to probe the structure and f...

On-axis plasma potential measurements have been made with an emissive probe in a low pressure !0.044 Pa" rf expanding plasma containing an ion beam. The beam is detected with a retarding field energy analyzer !RFEA", and is seen to disappear at high pressure !0.39 Pa". The emissive probe measurements are in very good agreement with corresponding measurements made with two separate RFEAs, and th...

The absolute densities of positive ions ~Cl2 1 and Cl! are obtained over a 2–20 mTorr pressure range and 5–1000 W input radio-frequency rf power range in a transformer-coupled Cl2 plasma. The relative number density of Cl2 1 is measured by laser-induced fluorescence. These laser-induced fluorescence data are calibrated by Langmuir-probe measurements of total positive-ion density at low powers t...

We analyze two-center interference effects in the yields of ionization of a dissociating hydrogen molecular ion by an ultrashort vuv laser pulse. To this end, we performed numerical simulations of the time-dependent Schrödinger equation for a H2+ model ion interacting with two time-delayed laser pulses. The scenario considered corresponds to a pump-probe scheme, in which the first (pump) pulse ...