Original Hanau Hollow Cathode Lamps (Cadmium)

Chemical Engineering

Accession Number: 2018.che.133.1-2

Description:

Two glass cathode lamps. Each lamp consists of a sealed glass tube with a black and white label housed in a grey plastic case with a clear lid and an orange-brown foam liner. The glass tubes are cylindrical. At the base of each tube is a silver and black tube plug with two metallic electrical pins protruding from one end.

Both tubes are “Cd” (Cadmium) tubes. Both tubes have a labelled max current of 10 MA.

2018.133.che.1: Has a paper insert in its plastic container. The glass of the tube is cloudy with a noticeable imperfection on the envelope. This tube has a narrow foam cushion between the glass tube and the case lid.

2018.133.che.2: Has a black mark along one side of the tube that may be a crack.

Primary Materials: Glass, Metal.

Markings:

2018.133.che.1: A black and white label affixed to the glass tube includes the following information: “Best.-Nr. 052 220”, “Nr. B 3 187”, A mark made by an inked stamp on the label reads “K. Q.”.

2018.133.che.2: A black and white label affixed to the glass tube includes the following information: “Best.-Nr. 052220”, “Nr. Do 250”.

Dimensions (cm):

Plastic cases are: Height = 6, Width = 9.6, Length = 17.2; Tubes: Length 14, Max Diameter = 4.5.

Function:

A Hollow Cathode Lamp (HCL) is a standard light source that produces a spectrum of light representing one or more chemical elements.

HCLs are used in atomic analysis instruments such as the atomic absorption spectrometer. The sealed glass tube contains an inert gas such as argon or neon. An element of interest is housed in the hollow cathode within the glass envelope. Current applied across the anode and cathode ionizes the gas within the tube creating a plasma. This ionized gas is accelerated towards the cathode, which sputters atoms off the sample element at the cathode. These freed atoms are excited by collisions within the plasma. When these atoms decay to a lower energy state, they produce a characteristic spectrum of light that can be compared to that of a sample for the purpose of chemical analysis.

Condition:

Good: The plastic cases are worn and dirty but intact. The tube of 2018.133.che.1 is cloudy with a noticeable imperfection on the envelope. 2018.133.che.2 has a black mark along one side of the tube that may be a crack.

Manufacturer: Original Hanau, Germany.

Date of Manufacture: 20th century, post c. 1955.

Provenance:

This artifact was acquired by the UTSIC collection from the University of Toronto Department of Chemical Engineering and Applied Chemistry on June 15, 2018.

  • Donated to UTSIC