Stormwater particles often provide transport for metals and other contaminants, however only larger particles are effectively removed by typical best management practices. Fine particles and their associated constituents are more likely to reach receiving waters; this merits further investigation regarding the metal contribution of fine (d p <10 μm) and very fine (d p <1.5 μm) particles. Road associated particles were collected by vacuuming a road surface and by collecting highway stormwater runoff. A cell sorter was employed to sort road associated particles into four size ranges: 0.1-0.3, 0.3-0.5, 0.5-1.0, and 1.0-1.5 μm. These very fine particles, along with six particle size ranges (total range <2-63 μm) separated using a settling column, were analyzed for Al, Mn, Fe, Cr, Ni, Cu, Zn, and Pb using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Enrichment factors (EFs), calculated using Al as a basis to represent crustal contributions, were similar for the vacuumed road dust and the stormwater runoff. Fe and Mn were minimally depleted (0.1x) or near Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. unity for all size ranges (Fe EF range 0.01-3.7; Mn EF range 0.02-10.6). Cr, Ni, Cu, Zn, and Pb were moderately (10x) to considerably (>100x) enriched for most size ranges; these metals were most enriched in the very fine fractions (max EF~4900 in Zn, 0.1-0.3 μm). Based on this preliminary study, a cell sorter is an acceptable means of fractionating aqueous particles of diameter 0.1-1.5 μm. In spite of their minimal relative mass contribution, the very fine particles are environmentally relevant due to their mobility and enrichment in potentially toxic metals.. NIH Public Access

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A MMIC chip set for millimeter-wave (mmW) communication systems has been developed. The highlights are a 3-stage Q-band LNA with 2.0 dB NW 22 dB of gain and a 2-stage V-band LNA with 2.3 dB NFI 15 dB of gain. Altogether, 7 MMIC chips (2 LNAs, 2 mixers, 2 downconverters, and 1 LO amplifier) make up this effort to develop low noise mmW building block functions in the InP HEMT technology.INTRODUCTION The MMIC chip set described here represents critical con kponents in future lightweight communication satellite applications. Not only are there considerable size and weight reductions in implementing higher levels of integration such as a downconverter MMIC chip ( Figures 1 aitd 2), but the improved reliability from having fewer Figure 1. Q-band MMIC downconvertet macro-cell layout.con iponents makes the creation of MMIC building block functions highly desirable. Future satellitv payloads have a ]wed for size and weight reductions in the EHF payload without sacrificing the system performam e. InP HEMTs can play a major role in meeting those needs. The InP HEMT structure (also known as AlInAs/CaIrtAs HEMT) ha., produced the lowest reported dtvice noise figure pthiformance at 60 GHz (about 1 d R ) with 9 dB of associated gain and the highest cutoff frequency ( > 300 GJ-lz)l. This paper djscusstIs the fabric.ation process, model development, circuit design, and measured results of 7 MMIC building block chips. 1133CH 1577-4/95/0-1133$01.00 0 1995 IEEE Figure 2. V-band MMIC downconverter macro-cell layout.

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