Johanson indicizer

Johanson predicted theoretical compactor operating conditions to handle air entrapment effects in materials. In general, he concluded that the critical compacting pressure level is dependent on a number of factors roll speed, roll diameter, powder permeability, compressibility, and compact strength. Johanson indicated, when applying these principles in commercial application, a compactor operator would have to operate the press at slightly less than maximum pressures to allow for material inconsistencies and variable in-feed flow rates. ... 

Johanson developed a very simple device they called the Johanson Indicizer system, or the Johanson Hang-up Indicizer, which they claim can predict material bridging in a hopper. This device was reviewed by Bell et al. In private conversations Johanson stated that they have employed this device with a number of pharmaceuticals. It simply compacts very small amounts of powder into a potential bridge and measures the force to break the bridge and allow the powder to flow. It is not designed to give any detailed information on the powder but only provides a test for powder bridging. This device is commercially available. 

Johanson, J.R. The johanson indicizer system vs. the jenike shear tester. Bulk Sohds Handhng 1992,2, 237-240. 

For the flowability, use the Johanson indices to characterize dry particles (see also related topics conveying solids. Section 2.6, storage bins. Section 10.3, mixing. Section 7.4) These indices are ... 

Table 1.13 Comparison of shear and powder bulk data obtained from a Jenike shear ceU and a Johanson indicizer.

Table 1.14 Comparison of the unconfined stress, /c, from the shear cells of Jenike and Peschl with the Johanson indicizer on BCR 116, a mineral oxide, com starch and flour.

Johanson, J.R. (1992) The Johanson Indicizer System vs. the Jenike Shear Tester. Bulk Solid Handling, 12(April-June), 273-240. 

All these problems are the result of the interaction of solids, solids flow properties, and the design of the equipment. Johanson (2002) has identified seven indices that relate to the bulk flow properties of solids. 

Studies have also been conducted comparing the Jenike direct shear test method to other test methods used to measure a powder s flowability (3), including the Hosokawa Micron Powder Characteristics Tester (Hosokawa Micron, Osaka, Japan), Peschl shear tester, and Johanson Hang-up Indicizer (Johanson Innovations, San Luis Obispo, California, U.S.A.). This is not an exhaustive list of all the powder testers available. In general each tester has its own test method, which measures some property of the powder that changes as the flowability changes. As stated previously, however, the term flowability must be taken in context. 

Bell TA. Ennis. BJ, Grygo RJ, et al. Practical evaluation of the Johanson hang-up indicizer. Bulk Solids Handling 1994 l4(l) 117-25. 

The last set of tests includes solid indicizers pioneered by Johaim-son. These include the Flow Rate and Hang-Up Indicizers [cf. Bell et al.. Practical Evaluaton of the Johanson Hang-Up Indicizer, Bulks Solids Handling, 14(1), 117 (Jan. 1994)]. They represent simplied versions of permeability and shear cell tests. Assumptions are made with regard to typical pressures and wall frictions, and based on these, a... 

Data describing the interaction of 2-butoxyethanol or 2-butoxyethanol acetate with other chemicals are scarce. Simulations of human pharmacokinetics of co-exposure to ethanol (0.1% in the blood) during an 8-hour exposure to 20 ppm 2-butoxyethanol with no exercise predict that the arterial levels of 2-butoxyethanol will be elevated as a result of a decrease in elimination rate (Johanson 1986, 1991a Johanson and Naslund 1988). Because the increase in 2-butoxyethanol is due to decreased elimination and not increased uptake, the rise and fall of blood concentrations of 2-butoxyethanol are slower in the ethanol co-administration model than in the increased workload model. A study in rats indicated that co-administration of ethanol and 2-butoxyethanol resulted in a higher blood level and a prolonged blood... 

Edward, J. T., Johanson, E. and Wold, S. (1988) Use of molecular connectivity indices in socio-historical and business management studies, in Graph Theory Notes of New York XV (eds J. W. Kennedy and L. V. Quintas), New York Academy of Sciences, New York, NY. 

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