Living and working in urban working class communities     

Kevin Ward  Colette Fagan 《Geoforum》2007,38(2):312-325

Much has been written on the apparent urban renaissance in UK cities and the new lifestyle arrangements, working time patterns, economic activities and the more general reordering of work and life that appears to accompany it. Certainly, recent decades have witnessed a range of economic, social and cultural changes in the lives of those living and working in cities and surrounding suburbs. Much of the attention in this work has focused on those groups for whom the changes have appeared most profound: the high-income earners returning to live in the city - the gentrifiers - or those who suffer multiple deprivations as a result of economic restructuring. Seemingly absent from many accounts of urban change are those places where, at first glance, the effects of change have been less pronounced: low-income, working class neighbourhoods where most people continue to get by, albeit in the context of a harsher, and less secure political economic context. In light of this apparent silence, this paper draws on interviews from Wythenshawe in South Manchester, to examine how low-income mothers cope, live and labour, in a rapidly changing city, as they perform paid work at the same time as ensuring the social reproduction of the household.  相似文献   

Detection of iodine monoxide radicals in the marine boundary layer using laser induced fluorescence spectroscopy     

Lisa K. Whalley  Kate L. Furneaux  Tom Gravestock  Helen M. Atkinson  Catherine S. E. Bale  Trevor Ingham  William J. Bloss  Dwayne E. Heard 《Journal of Atmospheric Chemistry》2007,58(1):19-39

A Laser Induced Fluorescence (LIF) instrument has been developed to detect iodine monoxide (IO) radicals in the atmosphere. An all solid-state Nd:YAG pumped Ti:Sapphire laser operating at approximately 445 nm was used to excite the (2,0) band of the IO A²Π_3/2 ← X²Π_3/2 electronic transition, with off-resonance fluorescence in the (2,5) band detected at 521 nm. The sensitivity of the instrument was determined by calibration. IO (between 10 and 150 pptV) was generated following the 184.9 nm photolysis of N₂O/CF₃I/N₂ mixtures with O₃ actinometry used to determine the photolysis flux. The detection limit was determined to be 0.3 pptV for a 300 s integration period, with an uncertainty of 23% (1σ). The instrument was deployed in August/September 2006 during the RHaMBLe (Reactive Halogens in the Marine Boundary Layer) campaign in Roscoff, France. Located on a small jetty, a few metres from the water’s edge at high tide, the instrument measured significant levels of IO on 11 days, with a maximum of 27.6 ± 3.2 pptV observed on one day (averaged over 10 s) representing the highest IO mixing ratio recorded in the marine boundary layer to date. IO displayed a clear diurnal profile with a maximum at low tide during the daytime. These results represent the first point measurements of IO in the atmosphere by LIF.  相似文献   

What to do with the oil when it is scraped up     

Trevor R. Dixon 《Marine pollution bulletin》1981,12(1):3

  相似文献   

Experimental duplication of a high-pressure megacryst/cumulate assemblage in a near-saturated hawaiite     

Janice Knutson  Trevor H. Green 《Contributions to Mineralogy and Petrology》1975,52(2):121-132

The occurrence of corroded megacrysts and cumulates of olivine, clinopyroxene, orthopyroxene, plagioclase, ilmenite and apatite in near-saturated hawaiites from the mid-north coast of New South Wales point to the derivation of these hawaiites at elevated pressures. In an experimental study on one of these hawaiites under conditions ranging from 5–15 kb and 0–5% H₂O, orthopyroxene was identified in only one run with 2% H₂O at 1040° C and 6.5 kb. In this run it was associated with olivine, clinopyroxene and Fe-Ti oxide. The early appearance of plagioclase in the “dry” experimental runs and amphibole in runs with 5% H₂O, indicates that the water content in the natural hawaiite was intermediate to these values. The near-duplication of the natural megacryst-cumulate assemblage suggests that the hawaiite host precipitated these phases at a depth of approximately 20–24 km, prior to rapid eruption to higher crustal levels.  相似文献   

A statistical model of the geomagnetic field     

Edward Irving  Martin A. Ward 《Pure and Applied Geophysics》1964,57(1):47-52

Summary A statistical model of the geomagnetic field is derived, based on the assumption of an axial geocentric dipole field of strengthH _e at the equator perturbed by randomly directed components of constant magnitudeh. The model fits the dispersions found from an analysis of the 1945 field, and the ratioh/H _e obtained for this field and from the palaeomagnetic data both average to about 0.4. The model predicts that during reversal of the dipole field, the field intensity falls to between 0.2 and 0.4 of the steady field intensity, and this agrees with estimates made from the palaeomagnetic observations.  相似文献   

Peralkaline rhyolites associated with andesitic arcs of the southwest Pacific     

I.E.M. Smith  B.W. Chappell  G.K. Ward  R.S. Freeman 《Earth and Planetary Science Letters》1977,37(2):230-236

  相似文献   

Cordierite breakdown under high-pressure,hydrous conditions     

Trevor H. Green  R. H. Vernon 《Contributions to Mineralogy and Petrology》1974,46(3):215-226

Clear evidence exists for a cordierite breakdown reaction to amphibole-kyanite-quartz in high-grade metamorphic rocks of the Arunta Complex, Australia. Using the natural minerals this reaction has been duplicated experimentally. It proceeds over a divariant band with a slope of 12±4 bars/°C, occurring between 8 and 10.4 kb at 750° C and between 9.5 and 11.3 kb at 850°C. The reaction is cut off at low temperature by the appearance of talc and at high temperature by the appearance of orthopyroxene. The maximum pressure stability of the amphibole-kyanite-quartz assemblage is about 20 kb. These data suggest that the natural rock was subjected to pressures of at least 8 kb at 750–850° C for high water fugacities. Other experimental data on the hydration of hypersthene and cordierite-hypersthene stability, point to a temperature below 820° C and an upper pressure limit of 9.5 kb at 750–820°C. Experiments at \(P_{{\text{H}}_{\text{2}} {\text{O}}}\) total indicate that the breakdown of cordierite to amphibole-kyanite-quartz is a hydration reaction, and occurred in the natural rock as a result of an increase of water fugacity at constant total pressure (8–9.5 kb) and temperature (750–820°C).  相似文献   

Cosmic‐ray exposure ages of six chondritic Almahata Sitta fragments          下载免费PDF全文

M. E. I. Riebe  K. C. Welten  M. M. M. Meier  R. Wieler  M. I. F. Barth  D. Ward  M. Laubenstein  A. Bischoff  M. W. Caffee  K. Nishiizumi  H. Busemann 《Meteoritics & planetary science》2017,52(11):2353-2374

The Almahata Sitta strewn field is dominated by ureilites, but contains a large fraction of chondritic fragments of various types. We analyzed stable isotopes of He, Ne, Ar, Kr, and Xe, and the cosmogenic radionuclides ¹⁰Be, ²⁶Al, and ³⁶Cl in six chondritic Almahata Sitta fragments (EL6 breccia, EL6, EL3‐5, CB, LL4/5, R‐like). The cosmic‐ray exposure (CRE) ages of five of the six samples have an average of 19.2 ± 3.3 Ma, close to the average of 19.5 ± 2.5 Ma for four ureilites. The cosmogenic radionuclide concentrations in the chondrites indicate a preatmospheric size consistent with Almahata Sitta. This corroborates that Almahata Sitta chondrite samples were part of the same asteroid as the ureilites. However, MS‐179 has a lower CRE age of 11.0 ± 1.4 Ma. Further analysis of short‐lived radionuclides in fragment MS‐179 showed that it fell around the same time, and from an object of similar size as Almahata Sitta, making it almost certain that MS‐179 is an Almahata Sitta fragment. Instead, its low CRE age could be due to gas loss, chemical heterogeneity that may have led to an erroneous ²¹Ne production‐rate, or, perhaps most likely, MS‐179 could represent the true 4π exposure age of Almahata Sitta (or an upper limit thereof), while all other samples analyzed so far experienced exposure on the parent body of similar lengths. Finally, MS‐179 had an extraordinarily high activity of neutron‐capture ³⁶Cl, ~600 dpm kg^?1, the highest activity observed in any meteorite to date, related to a high abundance of the Cl‐bearing mineral lawrencite.  相似文献   

Bayesian modelling of the cool core galaxy group NGC 4325     

Paul A. Russell  Trevor J. Ponman  Alastair J. R. Sanderson 《Monthly notices of the Royal Astronomical Society》2007,378(4):1217-1228

We present an X-ray analysis of the radio-quiet cool-core galaxy group NGC 4325  ( z = 0.026)  based on Chandra and ROSAT observations. The Chandra data were analysed using xspec deprojection, 2D spectral mapping and forward-fitting with parametric models. Additionally, a Markov Chain Monte Carlo method was used to perform a joint Bayesian analysis of the Chandra and ROSAT data. The results of the various analysis methods are compared, particularly those obtained by forward-fitting and deprojection. The spectral mapping reveals the presence of cool gas displaced up to 10 kpc from the group centre. The Chandra X-ray surface brightness shows the group core to be highly disturbed, and indicates the presence of two small X-ray cavities within 15 kpc of the group core. The xspec deprojection analysis shows that the group has a particularly steep entropy profile, suggesting that an active galactic nucleus (AGN) outburst may be about to occur. With the evidence of prior AGN activity, but with no radio emission currently observed, we suggest that the group in a pre-outburst state, with the cavities and displaced gas providing evidence of a previous, weak AGN outburst.  相似文献   

Cosmochemical and spectroscopic properties of Northwest Africa 7325—A consortium study          下载免费PDF全文

I. Weber  A. Morlok  A. Bischoff  H. Hiesinger  D. Ward  K. H. Joy  S. A. Crowther  N. D. Jastrzebski  J. D. Gilmour  P. L. Clay  R. A. Wogelius  R. C. Greenwood  I. A. Franchi  C. Münker 《Meteoritics & planetary science》2016,51(1):3-30

This work is part of a project to build an infrared database in order to link IR data of planetary materials (and therefore possible Mercury material) with remote sensing observations of Mercury, which will probably be obtained by the MERTIS instrument on the forthcoming BepiColombo mission. The unique achondrite Northwest Africa (NWA) 7325, which has previously been suggested to represent the first sample from Mercury, was investigated by optical and electron microscopy, and infrared and Raman spectroscopy. In addition, the oxygen, strontium, xenon, and argon isotopes were measured and the abundance of selected trace elements determined. The meteorite is a cumulate rock with subchondritic abundances of HFSE and REE and elevated Sr contents, which underwent a second heating and partial remelting process. Oxygen isotope measurements show that NWA 7325 plots in the ureilite field, close to the ALM‐A trachyandesitic fragment found in the unique Almahata Sitta meteorite breccia. On the other hand, mineralogical investigations of the pyroxenes in NWA 7325 provide evidence for similarities to the lodranites and acapulcoites. Furthermore, the rock is weakly shocked and argon isotope data record ancient (~4.5 Ga) plateau ages that have not been reset. The sample records a cosmogenic exposure age of ~19 Ma. Systematics of Rb‐Sr indicate an extreme early volatile depletion of the precursor material, similar to many other achondrite groups. However, despite its compositional similarities to other meteorite groups, our results suggest that this meteorite is unique and unrelated to any other known achondrite group. An origin for NWA 7325 as a sample from the planet Mercury is not supported by the results of our investigation. In particular, the evidence from infrared spectroscopy indicates that a direct relationship between NWA 7325 and the planet Mercury can be ruled out: no acceptable spectral match between laboratory analyses and remote sensing observations from Mercury has been obtained. However, we demonstrate that infrared spectroscopy is a rapid and nondestructive method to characterize mineral phases and thus an excellent tool for planetary surface characterization in space missions.  相似文献