John V. Hinshaw | Authors


Take Control of Resolution

Separation scientists may seek an optimum spot between chromatographic performance required to obtain sufficient results quality, and the time and resources needed to do so. This instalment of “GC Connections” examines the factors that control peak resolution-one of the main drivers of separation quality-and how chromatographers can use this information to find an optimum between time, cost, and performance.

Flow, Pressure, and Temperature Calibration: Part II

In last month's installment of "GC Connections," John Hinshaw discussed how peak retention times depend upon relationships between pressure, flow rate, oven temperature, column dimensions, and stationary phase. This concluding installment of a two-part series discusses the effects that column variability has on isothermal capillary gas chromatography and explores instrument calibration with the goal of maximizing instrument-to-instrument similarity of retention times.

Strategies for GC Optimization, Part II - Columns

In this month's "GC Connections," John Hinshaw examines optimization strategies for gas chromatography columns in the second installment of a multipart series. He starts with a question from a reader and then discusses broader column issues.

Basic GC Measurements and Calculations

This month's column reviews some basic GC measurements and calculations that can be applied to questions of column quality. By understanding the analytical process, chromatographers can improve the quality of their results.