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This month's installment discusses the laboratory deployment of gas cylinders with appropriate pressure regulators, gas filtration, and gas fittings, as well as the question of cylinder retirement. A previous 'GC [...]

The Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (Pittcon) returned to Chicago's McCormick Place for its 65th annual meeting on March 2-6, 2014. This year, more than 16,200 conferees [...]

Carrier and detector gases, when not generated directly on-site, are transported to laboratory facilities in gas cylinders and stored there until they are used. A recent 'GC Connections' installment (1) [...]

Have you wondered how the gas chromatography (GC) carrier gases helium, hydrogen, argon, and nitrogen are transformed from their natural conditions or precursors into highly purified compressed states inside laboratory [...]

While gas chromatographers may take their septa for granted, in fact these small and seemingly unremarkable polymer disks keep air out of the carrier-gas stream when used in an inlet [...]

Questions about how practical proposed gas chromatography (GC) method changes are often come up during optimization for speed and resolution, or while converting to a different carrier gas. Related objective [...]

L Laminar flow: The smooth time-invariant flow that develops when a liquid is moving under conditions where viscous forces dominant over inertial forces. Laminar flow is characterized by a low [...]

This month in 'GC Connections' John Hinshaw examines the anatomy of chromatographic peaks with attention to features that help determine the suitability of individual chromatographs for a specific analysis task [...]

In this month's installment, we examine long-distance running as a metaphor for gas chromatography separations. For those readers who cannot stop thinking about work while on vacation, here is a [...]

John Hinshaw's review of gas chromatography (GC) instruments and accessories that were newly on display at the Pittsburgh Conference in March 2013, or were introduced to the marketplace in the [...]

Obtaining and reproducing accurate, repeatable flow measurements is of great importance to chromatographers. The quantitative accuracy of their instruments depends on being able to accurately set and measure flow rates [...]

This month we complete a list of questions about gases that began in an earlier installment. The range questions about gases in gas chromatography (GC) is wide and complex. Even [...]

Gas chromatography (GC) resolution and sensitivity are often limited by matrix effects in 'real world' samples that originate outside of a laboratory. GC separation and detection may encounter interference from [...]

It has been about nine years since this list was last published in LCGC (1). During the interim, my toolbox has gained some new items, and a few others have [...]

The 2012 Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (Pittcon) was held March 11-15 in Orlando, Florida, at the Orange County Convention Center. The 63rd annual occurrence of this [...]

At some point, you may need to bring an idle capillary GC inlet, column, and detector back to operating condition. Here is what to do--including column installation, electronic pneumatic control [...]

This month's GC Connections discusses the fundamentals of instrumentation for headspace sampling, including vial thermostating pressurization, and transfer to the gas chromatograph's inlet. ********** The previous installment of this column [...]

Previous installments in this series covered the basics of valving and its applications in gas chromatography (GC). This month, we will discuss the use of fluidic switching devices for open-tubular [...]

Headspace sampling for gas chromatography (HSGC) prevents nonvolatile residue accumulation in the inlet and column entrance while simplifying sample preparation. This installment of 'GC Connections' addresses some of the details [...]

Multidimensional gas chromatography (MDGC) as practiced today may be divided into two main application areas: Classical MDGC and comprehensive two-dimensional gas chromatography (GCXGC). Classical MDGC involves redirecting a portion, or [...]

The 62nd annual Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (Pittcon), March 13-18, 2011, returned to Atlanta, Georgia, for the first time since 1997. I particularly enjoyed Atlanta for [...]

Chromatographers have employed valves for sample injection and flow redirection since the beginnings of gas chromatography (GC). In this issue, John Hinshaw begins a series of articles on valves for [...]

Gas chromatographers are using hydrogen carrier gas more and more as both an inexpensive and a readily available substitute for helium, as well as to gain some performance improvements. In [...]

The previous installment in this series looked at how moderate peak tailing affects resolution and degree of peak overlap. When peaks tail, even moderately, extra time between them is required [...]

Part I of this series (1) reviewed the calculation of the resolution of two adjacent peaks, repeated here in equation 1. A version of the resolution equation commonly used in [...]

The 61st annual gathering of the Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy migrated south to Orlando, Florida, and met February 28-March 5, 2010. On Wednesday night, Universal Studios' [...]

Technologies for laboratory analysis advance continuously, just as do computer technologies or transportation technologies. Small advances tend to occur fairly often while major new technologies appear less frequently. As new [...]

In this month's 'GC Connections,' John Hinshaw investigates how much air enters a gas stream in the face of extreme leaks in an attempt to gauge the potential effects of [...]

In this month's installment of "GC Connections," John Hinshaw takes a break from the purely technical and visits a number of chromatography forums and discussion groups, both virtual and old-fashioned [...]

In the world of practical chromatography, peak shapes only approach an ideal Gaussian statistical distribution. Solute band shapes are perturbed by extracolumn volumes, nonideal retention processes, and strong adsorptive interactions [...]

The Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy returned to McCormick Place in Chicago, Illinois March 8-12, 2009, for the conference's 60th annual gathering. This year, conferees were spared [...]

In an ideal world, chromatographic peaks always would be perfectly shaped, symmetrical Gaussian entities, but in the real world of inlets, columns, and detectors, much can happen to distort peaks' [...]

Detectors are another link in the chain of signals that a chromatographic analysis generates. After separation, a detector transduces the chemical signals of eluted analytes to an electrical signal that [...]

Chromatographers are choosing hydrogen carrier gas more often for their applications for reasons of performance and, in the face of increasing helium prices, for cost reasons as well. In this [...]

This month in "GC Connections," John Hinshaw concludes a two part series on what happens when high voltage spikes attack modern electronic equipment, what to do when they occur, and [...]