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Summary 2-methyl-1,4-benzoquinone as a target compound of the tergal gland secretion of the rove beetle,Aleochara curtula, was quantified from the reservoirs of individual beetles. Males store less secretion than females, and they evaporate more of the secretion as measured by adsorption from the air (closed-loop-stripping-analysis). The amount of emitted quinone is increased during aggressive interactions of rival males. The pulsed emission of the secretion during aggression is demonstrated by a novel technique combining observation of behavior with the on-line measurement of target fragment ions by mass-spectrometry (tandem bioassay — mass fragmentography). The emission of the secretion is used as a weapon in combats between males and may result in the repulsion of subordinate males from the mating site, but may also serve to mimic females chemically in order to avoid aggressive encounters.  相似文献   
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Three treatment cells were operated at a site near Durango, CO. One treatment cell operated for more than 3 years. The treatment cells were used for passive removal of contamination from groundwater at a uranium mill tailings repository site. Zero-valent iron [Fe(0)] that had been powdered, bound with aluminosilicate and molded into plates was used as a reactive material in one treatment cell. The others used granular Fe(0) and steel wool. The treatment cells significantly reduced concentrations of As, Mn, Mo, Se, U, V and Zn in groundwater that flowed through it. Zero-valent iron [Fe(0)], magnetite (Fe3O4), calcite (CaCO3), goethite (FeOOH) and mixtures of contaminant-bearing phases were identified in the solid fraction of one treatment cell. A reaction progress approach was used to model chemical evolution of water chemistry as it reacted with the Fe(0). Precipitation of calcite, ferrous hydroxide [Fe(OH)2] and ferrous sulfide (FeS) were used to simulate observed changes in major-ion aqueous chemistry. The amount of reaction progress differed for each treatment cell. Changes in contaminant concentrations were consistent with precipitation of reduced oxides (UO2, V2O3), sulfides (As2S3, ZnS), iron minerals (FeSe2, FeMoO4) and carbonate (MnCO3). Formation of a free gas phase and precipitation of minerals contributed to loss of hydraulic conductivity in one treatment cell.  相似文献   
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Book reviews     
ANALYTICAL PLANNING: THE ORGANISATION OF SYSTEMS

Thomas L. Saaty and Kevin P. Kearns

Pergamon Press, 1985. Price: U.S. $40.00, U.K. £29.50.

THE GEOGRAPHER AT WORK

Peter Gould

Routledge and Kegan Paul, London 1985’ Price: £8.95.

UTOPIA ON TRIAL

Alice Colman

Hilary Shipman Ltd., 19 Framfield Road, Highbury, London. May 1985 (reprinted August, 1985). Price: £7.95.

SIR RAYMOND UNWIN: ARCHITECT, PLANNER AND VISIONARY

Frank Jackson

A. Zwemmer Ltd., London 1985. 187 pp. with maps and illustrations.

STRATEGIC PLANNING IN ACTION: THE IMPACT OF THE CLYDE VALLEY REGIONAL PLAN 1946–1982

R. Smith and U. Wannop (eds)

Gower, 1985, 272 pp. Price: £16.50.

LOCALITIES, CLASS AND GENDER

The Lancaster Regionalism Group (Linda Murgatroyd, Mike Savage, Dan Shapiro, John Urry, Sylvia Walby, Alan Warde, with Jane Mark‐Lawson)

Pion Ltd., 1985. Price: £12.00.  相似文献   

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Child‐ and youth‐friendly spaces have become a common feature of emergency humanitarian provision. This study reports on the outcomes of child and youth learning centres (CYLCs) in Ethiopia's Buramino Camp established for those fleeing conflict in Somalia. Eighty‐five youths completed baseline assessments shortly after arrival and follow‐up assessments three to six months later. Caregivers of 106 younger children completed similar appraisals. 693 children attending the CYLCs completed pre‐ and post‐educational assessments, which indicated major gains—significant at p<0.0001—in both literacy (younger children, t=9.06; youth, t=13.87) and numeracy (younger children, t=13.94; youths, t=17.10). Children's CYLC attendance increased reports of met needs among caregivers (t=2.53, p<0.05) and youths (t=2.57, p<0.05), and, among caregivers but not youths, significantly moderated protection concerns (t=2.39, p<0.05, and t=?1.90, p=0.06, respectively). There was general improvement in psychosocial well‐being over time for all children; CYLC attendance predicted greater reductions in reported difficulties only among younger children (t=2.51, p<0.05).  相似文献   
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The electrodes in industrial precipitators collect many tons of dust daily, and the efficient transfer of this dust burden to the hoppers is a challenging problem in mechanical engineering. Many varieties of devices have been tried; hammers, vibrators, scrapers, water flushing, gas blasting, etc. Impact devices for this purpose are usually called “rappers.” Laboratory experiments described in this paper show that normal (perpendicular) rapping is more effective than shear rapping; that thick dust layers are more easily removed by rapping than thin ones; that rapping becomes easier with increasing temperature, within limits; and that the electrostatic forces acting upon the precipitated dust layer play an important role. Quantitative data are shown graphically. The relation of these results to previous studies by other investigators is discussed.  相似文献   
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