An inexpensive apparatus for automatic continuous dehydration

An apparatus is described for automatic dehydration of material using the principle of continuous dilution. Specimens may be dehydrated, in a period chosen by the operator, for as little as 30 min to as much as 16 hr (overnight). The apparatus is inexpensive both to construct and to run.     

An automatic homocontinuous culture apparatus

An apparatus for the cultivation of microorganism under controlled conditions is described. This apparatus is basically a turbidostat improved with automatic devices for sample withdrawal and tube cleaning. The results of experiments, using Euglena gracilis to check the constancy of some physiological parameters (in particular phototactic reactivity), are reported.     

Liquid-metering device for continuous culture

A device is described for aseptically metering liquids at rates as low as 10 ml./hr. The metering rate is constant, but can be readily changed. The device delivers a measured increment of liquid every 10 sec. The volume added is controlled by electrical contants in an electrolyte tube. The medium does not enter this tube.     

Working design for a 5-liter controlled continuous culture apparatus

A continuous culture apparatus of 5-liter capacity is described which is capable of control of dissolved oxygen. Combined turbidostat and constant feed operation permit control of cell population density and one or more nutrients. A system for the measurement of oxygen uptake and CO₂ output is described. Sufficient detail is supplied to enable construction and operation of the apparatus.     

An apparatus for the continuous culture of bacteria at constant generation times

Summary An apparatus for continuous culture of bacteria at constant generation times is described, analogous toNovick andSzilard's “chemostat” and the apparatus ofMonod. Detailed instructions for the use of the apparatus are given and a method for the determination of the vessel constant is described. The theory and the interesting possibilities of the apparatus for a number of fundamental problems in bacteriology are shortly discussed.     

An automatic soil-washing apparatus for fungal isolation

Summary An apparatus for serial washing of soil particles is described. When forest humus was washed 50 times in an illustrative experiment, the proportion of dark and slow-growing mycelia among fungal isolates was increased from 5 to over 50 per cent.     

An automatic recording device for measuring phytochrome with a dual wavelength Ratiospect

Summary An automatic recording device for irradiating and measuring phytochrome in very dense samples with a dual wavelength Ratiospect has been developed. The mechanical and electrical layouts are described in detail.     

An improved electroantennogram apparatus with a new automatic sample injection system

ABSTRACT. An improved electroantennogram (EAG) apparatus with a new automatic sample injection system, based on a cyclic timer connected to a 12VD.C. electrovalve, is described. The device is fully automatic and allows insertion of constant cyclic air puffs of the test compounds to the antenna at predetermined intervals.     

An electrophoretic device concentrating charged macromolecules to a predetermined final solution volume

An apparatus for electrophoretic concentration of charged macromolecules to a predetermined final solution volume has been developed. The concentration process has a yield of near 100%, which implies that it is possible to predetermine the final macromolecule concentration as well. Both the final macromolecule solution volume and concentration are nearly independent of the electrophoresis time when it exceeds a certain minimum value. The electric field strength across the boundary containing the concentrated macromolecule solution is very low. This considerably reduces macromolecule aggregation, adsorption, and denaturation at this boundary compared to conventional electrophoretic concentrator designs. Both one-stage and two-stage versions of the apparatus have been developed. The one-stage version easily yields a 10-fold and the two-stage version a 50-fold concentration of the macromolecules. Typical macromolecule solution start volumes are 20-50 ml.