Field meeting in the Mole Gap: Saturday, 6th May, 1933     

A.J. Bull 《Proceedings of the Geologists' Association. Geologists' Association》1933,44(3):312-313

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Field meeting at Godstone,Surrey: Saturday, 11th May, 1946     

A.J. Bull 《Proceedings of the Geologists' Association. Geologists' Association》1946,57(3):172-173

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Distribution Maps of BCS Membership as at 31st December 1969     

J. Bull 《The Cartographic journal》2013,50(2)

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Seismic behavior of steel buildings with out‐of‐plumb          下载免费PDF全文

Ali A. Rad  Gregory A. MacRae  Trevor Z. Yeow  Desmond K. Bull 《地震工程与结构动力学》2015,44(14):2575-2588

A structure that has a permanent offset from a true vertical line is commonly referred to as being ‘out‐of‐plumb’. Out‐of‐plumb may result from construction tolerances or post‐earthquake permanent deformations in steel buildings. This paper quantifies the displacements of buildings with out‐of‐plumb in subsequent seismic events by means of inelastic dynamic time history analysis. Structures considered have different structural heights, force design reduction factors (R), and target inter‐story drifts. It is shown that buildings with greater out of plumb and force design reduction factor have larger normalized peak inter‐story drift ratio and ratio of residual‐to‐peak drift. Also, the ratio of residual‐to‐peak drift was not strongly dependent on structural height or design drift. A design procedure and example provided, based on the results obtained, show how peak and residual inter‐story drift ratio can be estimated. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Links between climate variation and year class strength of New Zealand hoki (Macruronus novaezelandiae): An update     

B. Bull  M. E. Livingston 《新西兰海洋与淡水研究杂志》2013,47(5):871-880

Hoki (Macruronus novaezelandiae Hector) year class strength (YCS) varies substantially from year to year. We examined associations between YCS and climate variables including the Southern Oscillation Index (SOI), satellite sea surface temperatures (SSTs), synoptic weather patterns, wind speeds, and the depth of the west coast, South Island, New Zealand, mixed layer. We evaluated the predictions of a model developed 2 years ago to predict YCS of the western and eastern New Zealand hoki stocks from similar climate variables. New predictive models were developed using updated data. Strong year classes of the western hoki stock were associated with cooler SSTs, a negative SOI, and westerly or south‐westerly flow along the west coast of the South Island. We accordingly predict a moderately strong 1997 year class and weak 1998 and 1999 year classes for the western stock of hoki. The current model cannot predict eastern stock year class strengths with confidence.  相似文献   

Tracking the fate of dung-derived carbohydrates in a temperate grassland soil using compound-specific stable isotope analysis     

Jennifer A.J. Dungait  Roland Bol  Ian D. Bull  Richard P. Evershed 《Organic Geochemistry》2009,40(12):1210-1218

Carbohydrates are major organic components of dung and are likely to contribute substantially to increased carbon stocks in manured soils. To investigate this hypothesis, a field-scale experiment was conducted on a temperate grassland site in Devon, UK. C₄ dung (bulk δ¹³C value ?12.6‰) was applied to a temperate grassland C₃ soil (bulk δ¹³C value ?30.3‰) in April and the surface soil beneath cow pats sampled at seven dates over a year. Total carbohydrates were extracted as their monosaccharide components and analysed as the alditol acetates using gas chromatography. The δ¹³C values of the major monosaccharides glucose (?11.5 ±0.6‰), xylose (?10.4 ±0.4‰), arabinose (?10.4 ±0.5‰) and galactose (?8.3 ±1.6‰) extracted from the C₄ dung via acid hydrolysis were indicative of their source. Their weighted mean δ¹³C value was ?10.8‰, 1.8‰ more ¹³C-enriched than the bulk dung value. The δ¹³C values of individual monosaccharides recovered by acid hydrolysis in the 0–1 cm and 1–5 cm soil horizons beneath C₄ cow pats, compared with control soils determined over 372 days, allowed assessment of the extent of incorporation and fluxes of dung-derived monosaccharides. A maximum of 60% of the dung C in soil was derived from carbohydrates after 56 days, declining to around 20% after 372 days. Incorporation dynamics varied between monosaccharide species. Glucose, xylose and arabinose behaved in a similar manner because of their predominantly plant cell wall derived provenance in the dung, whilst dung-derived galactose and mannose appeared to have a microbial source in the soil. The dynamics of total dung-derived monosaccharides in the top 5 cm was comparable to incorporation and flux of bulk dung C, previously estimated using bulk δ¹³C values. The movement of dung-derived carbohydrates into the soil was inequivalent between the 0–1 cm and 1–5 cm horizons. The lack of a significant difference in concentration, but the evidence for the persistence of dung-derived monosaccharides in soil based on δ¹³C values, indicated replacement of existing pools in the soil, suggesting that the ability of this particular soil to sequester further C derived from carbohydrates was limited.  相似文献   

The Palaeomagnetism of some Hypabyssal Intrusive Rocks from South Victoria Land, Antarctica     

C. Bull  E. Irving 《Geophysical Journal International》1960,3(2):211-224

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Fission-track retention age of the Bondoc mesosiderite     

R.K. Bull  S.A. Durrani 《Earth and Planetary Science Letters》1980,49(2):181-187

Whitlockites have been extracted from the Bondoc mesosiderite and found to contain ～(0.7–2.7) × 10⁶ cm^?2 of spontaneous-fission tracks. Thermal-neutron irradiation of these crystals along with terrestrial apatite age standards, and measurement of the track densities so induced, lead to the determination of a whitlockite track-retention age of 2.68 (±0.30) Gyr for Bondoc, which is essentially independent of the initial (Pu/U) ratio.This young age is in qualitative, and, within the experimental uncertainties, in quantitative, agreement with the slow cooling rates determined for many mesosiderites [1,2] and specifically for Bondoc [6] from Ni distributions in the metal phase.  相似文献   

Chemical textures on quartz grains: An experimental approach using salts     

A. W. Magee  P. A. Bull  A. S. Goudie 《地球表面变化过程与地形》1988,13(8):665-676

Two groups of fresh crushed Brazilian quartz grains (0.4–0.6 mm) were placed in 10 ml of various saturated salt solutions (sodium sulphate, sodium chloride, magnesium sulphate, sodium carbonate, and sodium carbonate and soil). One group was placed in an environmental cabinet programmed to simulate summer diurnal temperature and relative humidity values recorded in Wheeler Valley, a dry valley in southern Victoria Land, Antarctica. The other group was allowed to remain at normal laboratory conditions. Quartz grains from both groups were removed at pre-selected intervals for examination using the scanning electron microscope. After 50 hours chemical surface textures were formed on the quartz grains in all but the sodium sulphate solution. At the 140 hour interval all the salt solutions used were producing chemical surface textures on the quartz grains. This paper demonstrates that chemical surface textures can be produced on quartz grain surfaces by saturated salt solutions in a short period of time and may prove to be representative of chemical surface textures produced in a saturated saline environment.  相似文献   

The design of precast concrete pavements on low bearing capacity subgrades     

R. F. Ackroyd  J. W. Bull 《Computers and Geotechnics》1985,1(4):279-291

By using the finite element method and combining it with Westergaard's analysis for concrete pavements, a new design method using 2 metre by 2 metre precast concrete pavement units is presented for heavy duty pavements on low bearing capacity subgrades. One design example is included.  相似文献