scholarly journals Preliminary map showing construction materials in the south one-half of Williams County, North Dakota

1947 ◽  
Author(s):  
2014 ◽  
Vol 629-630 ◽  
pp. 449-454
Author(s):  
Adamantia Zografou ◽  
Andrew Heath ◽  
Peter Walker

The extraction of china clay in the South West of the UK generates waste in a mass ratio of 1:9 for china clay: waste. Currently, part of the coarser waste, “stent” and sand named “china clay sand” (CCS) in this study, is used as building stone or secondary aggregate in concrete and asphalt but the finest waste fraction, called “mica” waste, is used only for the restoration of old quarries. Looking for innovative solutions for the needs of a new Eco-town in the UK, and with regard to uses commercially applicable to construction and of low environmental impact, the china clay waste is being studied as an aggregate in alkali-activated cements (AAC). Aiming to replace primary aggregates with wastes in low risk construction materials, a series of AAC concrete based on a 50% GGBS and 50% fly ash (FA) blend and an equivalent Portland concrete series were produced. In the mixes the primary aggregate was steadily replaced by forms of the waste and tests in compression showed a decreasing trend in strength accordingly. The two series of concrete follow approximately the same ratios of decrease although in absolute values the AAC series reached higher range of strengths on the 28 day compared to the Portland series. While the use of CCS did not have any negative impact, the addition of mica decreased the strength up to 25% more.


2018 ◽  
Vol 10 (3) ◽  
pp. 79
Author(s):  
Eric Clausen

The Beaver Creek drainage basin is located along the North Dakota-Montana border slightly to the south of a recognized continental ice sheet margin and immediately to the east of the deep northeast-oriented Yellowstone River valley with Beaver Creek flowing in a north and northeast direction to join the north-oriented Little Missouri River. The Beaver Creek drainage basin originates on an escarpment-surrounded upland and its erosional history was determined by analyzing detailed topographic maps aided by previously made field observations that showed coarse-grained and distinctive alluvium had been transported in an east direction across the Beaver Creek drainage basin and across what is now the deep Little Missouri River valley to sediments making up southwest North Dakota high points containing both the distinctive alluvium and Oligocene age fossils. Drainage divides surrounding the Beaver Creek drainage basin show numerous divide crossings (or notches) linking northwest-oriented Yellowstone River tributary valleys with east-oriented Beaver Creek tributary valleys and west- or northwest-oriented Beaver Creek tributary valleys with southeast- or east-oriented Little Missouri River tributary valleys and suggest the Beaver Creek valley eroded headward across a large-scale flood formed anastomosing channel complex. Buttes located just to the east of the Beaver Creek-Little Missouri River drainage divide suggest the east-oriented water removed as much as 150 meters, or more, of Beaver Creek drainage basin bedrock, and even greater amounts of bedrock from regions to the south of the Beaver Creek drainage basin. Topographic map evidence and routes traveled by the distinctive alluvium suggest a continental ice sheet blocked a large and high-level northeast-oriented river and diverted at least some of the water along the ice sheet margin with the east-oriented floodwaters being captured in a progressive sequence by headward erosion of the Little Missouri River, Beaver Creek, and Yellowstone River valleys (in that order).


1962 ◽  
Vol 24 (2) ◽  
pp. 303-322 ◽  
Author(s):  
Bernard Cosman
Keyword(s):  

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.


ASHA Leader ◽  
2006 ◽  
Vol 11 (16) ◽  
pp. 16-17
Author(s):  
Bobbie Houn ◽  
Kolette Trottier
Keyword(s):  

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