Entries by jennie.jenkins

What is the best way to do trace metal sampling?

1. All samplers contaminate or distort in some way. • Plastics may leach metals from ultraviolet inhibitors, metal-organic plasticizers, (rarely) metal catalysts. • Teflon has a rough porous surface into which ions, fine charged particles, and very fine particles may become attached. Errors may occur in your first sample due to these trapped trace elements. […]

What is contained in a sampler kit?

A note about our sampler kits: “Kits” usually include line or cable, messenger and case and are intended for immediate use in the field. Our goal is to provide everything you need, so you don’t waste precious effort and money scrounging. Frankly, we do not recommend purchasing a sampler without a case for obvious reasons: […]

What is a Surber on a stick?

It may sound like something delicious on a hot summer day, but it is actually the new standard sampler recommended by the EPA and USGS. This phrase refers to our modified kick net with 60” handles in 500 mm Nitex® mesh (425-M53 or 425-N53). Also termed a “Slack sampler,” it has sold widely to customers […]

What is a messenger?

The work horse of water sampling is the simple messenger, the bullet-shaped weight which strikes the trip mechanism and snaps the sampler shut. Send the messenger down the line when you are ready to take your sample – you choose where and when. When you lower your bottle or dredge into the water,it remains open […]

What are the uses of analyzing fish?

Fish, which share many physiological properties with mammals, are a highly visible part of most aquatic habitats with over 775 species in North America alone. Critical to many natural food chains, they are a source of food, recreation and economic growth and affect the plankton, macrophytes and other aquatic organisms with whom they coexist. Fish […]

What are Kemmerer bottles?

Based on a 1927 design by Dr. George Kemmerer, University of Wisconsin, the Kemmerer bottle has long been favored by limnologists and fishery biologists. With few moving parts and a foolproof trip, it offers a trouble-free life. Clear acrylic cylinders have the advantage of being transparent: you can see the sample before removal. You can […]

What are Core Samplers?

A core, in marine research, is a cylindrical section taken from sediments underlying a water body. Core samplers, the instruments used to obtain cores, range from the simple to the complex. The variety of corer types reflect the breadth and variety of marine research. For example, the simplest corers are hand-operated types used in shallow […]

What are Characteristics of good core samplers?

Perpendicular placement: The core sampler must make a vertical or straight entry into sediments to secure a reliably representative cross-section sample. Penetration: It must penetrate the sediments you expect to find and adaptable for many field situations. Core retention: There should be minimal loss of any part of the sample during return to the surface. […]

U.S. Standard Sieve Sizes

U.S. standard mesh or sieve numbers, widely used in geological particle sizing, are arbitrary designations and do not refer to actual mesh count. They are the open width of one side of the square aperture and are made to micron sizes, not English measurements, using heavy wire woven with square holes. The standard sieve for […]