scholarly journals Drenagem e acumulação de ar frio em noites de arrefecimento radiativo. Um exemplo no vale de Barcarena (Oeiras)

Finisterra ◽  
2012 ◽  
Vol 30 (59/60) ◽  
Author(s):  
António Lopes
Keyword(s):  
Drainage System ◽  
Field Research ◽  
Intermittent Flow ◽  
Cold Air ◽  
Climatological Field ◽  
Irradiation Process

THE COLD AIR DRAINAGE DURING CALM CLEAR NIGHTS: AN EXAMPLE IN HE BARCARENA VALLEY (OEIRAS, PORTUGAL) - The cold air drainage system is a recent climatological field research in Portugal. In the valley of Barcarena, a few kilometres westward from Lisbon, it was possible to detect the intermittent flow of the cold air drainage during two calm clear nights. We came to the conclusion that the cold air lakes are formed in situ by the irradiation process and also by the accumulation of the cold air drained along the valley slopes. The rugosity of the surface and the slow down of the cold air along the slope could be responsible for the oscillations of the cold air lakes thickness

scholarly journals In Situ Performance Assessment and Evaluation of Hydrophobic and Ultraviolet Protective Treatments for Historic Log Structures

2015 ◽  
Vol 38 ◽  
pp. 100-111
Author(s):  
Courtney Magill ◽  
Frank Matero
Keyword(s):  
Field Research ◽  
Accelerated Weathering ◽  
Assessment And Evaluation ◽  
Appropriate Treatment ◽  
Wood Coatings ◽  
Subsequent Phase ◽  
Initial Results ◽  
Ongoing Project

Beginning in the summer of 2015, research was conducted on protective wood coatings and accelerated weathering testing methods for architectural log and timber. A rack for supplementary natural weathering testing of hydrophobic and ultraviolet protective surface treatments for logs was also erected as a subsequent phase at Grand Teton National Park. This laboratory and field research is part of an ongoing project to develop an appropriate treatment for historic log structures in the region that will preserve their original fabric while maintaining the intended historic appearance of the buildings, i.e., unpainted. The weathering rack will be in place for upwards of five years to verify the lab-based results from Phase I and to determine the long-term durability of the chosen treatments on already aged materials in situ. This report addresses the methods and materials for preparation of the weathering rack and samples as well as the methods being used to monitor their progress and initial results. Readings will be taken yearly to monitor the effects of weathering on each treatment.

scholarly journals Radioactive Contamination due to 241Am Lightning Rod Failure

2020 ◽  
Vol 13 ◽  
pp. 262
Author(s):  
K. L. Karfopoulos ◽  
G. N. Papadakos ◽  
D. J. Karangelos ◽  
P. K. Rouni ◽  
N. P. Petropoulos ◽  
...  
Keyword(s):  
Health Risk ◽  
Gamma Ray ◽  
Surface Soil ◽  
Collection Efficiency ◽  
Drainage System ◽  
Radioactive Material ◽  
Building Roof ◽  
The Public ◽  
The People

It is estimated that until 1978 about 200000 lightning conductor rods with -a emitting sources attached to their end were installed worldwide. The sources were supposed to increase the lighting collection efficiency of these rods through the ionization of the surrounding air. Nevertheless, this improvement has never been established conclusively. Such devices are, in most cases, not accessible by the pub- lic; therefore, the dose to the population is considered insignificant. However, the possibility of radioactive material leakage, due to the source attachment failure, and the subsequent contamination of the surroundings that could lead to possible health risk of the public cannot be excluded. In this work, the case of 241Am contamination due to a lightning rod conductor failure is investigated. This contamination was accidentally detected on the surface soil around a laboratory building in the National Technical University of Athens Campus, during a routine in-situ gamma-ray measurement campaign that took place in 2003. A detailed survey revealed that this 241Am contamination was due to the leakage from two lightning rods on the building roof. Consequently the rods were removed from the building and the contamination pattern on the roof and on the surface soil around the building was examined in detail. From the results obtained so far it may be concluded that there exists well localized contamination on the roof and also around the building. It was established that the pathway through which contamination reached the ground was  the rainwater drainage system of the building. The gamma ray dose rate due to 241Am contamination found on the roof and on the surface soil is low compared to that due to its natural radioactivity and does not seem to pose any health risk to the people working in the building or to the public.

The Water Mandarins: The Contradictions of Urban Water Provision

2004 ◽  
Author(s):  
Erik Swyngedouw
Keyword(s):  
Urban Population ◽  
Water Distribution ◽  
Tap Water ◽  
Water System ◽  
Field Research ◽  
Intermittent Flow ◽  
Urban Water ◽  
Investment Planning ◽  
Water Company ◽  
Water Provision

Billions of litres of water flow through the centre of Guayaquil each day, as the Rivers Daule and Babahoyo converge to form the River Guayas. Given this fact, it is perplexing to find that 35% of the inhabitants of the city do not have access to adequate and reliable water supplies and the whole city suffers from chronic absolute water shortages. In this and the next chapter, we shall explore the contradictions of urban water provision, which result in a sizeable part of the urban population, invariably the poorer end of the social spectrum, not having access to piped potable water. This situation, in turn, makes them easy victims of water speculators, the private water sellers that distribute water in non-serviced areas by means of tankers. In Guayaquil, approximately 400 tankers service a population of half a million people, or approximately 35% of the total urban population. These water-merchants buy water at a highly subsidized price (70 sucres/m3),while they sell it for up to 6,500 sucres/m3 (November 1993), a price of up to 300 times higher than that paid by low-volume consumers who receive water from the water company. We will also explore the strategies and structure of the water company, infrastructure and investment planning, price mechanisms and control structures in the light of these exclusionary and disempowering mechanisms of the existing water system. In short, we shall explore the contradictory dynamics of the ‘Water Mandarins’. The complex networks of those that hold control over the water tap, water infrastructure, and water distribution will be excavated in order to unearth the relations of power that infuse and eventually organize the intermittent flow of water in Guayaquil. Of course, analysing the changing dynamics of water supply in Guayaquil is like trying to hit a moving target. The field research for this book was completed in 1998. Since then, the public water company has awarded a concession to International Water Services, a Dutch-based subsidiary of Bechtel and Edison Spa, to operate, administer, and expand Guayaquil’s water and sewage services and infrastructure (see below).

scholarly journals Novel Copper Photoredox Catalysts for Polymerization: An In Situ Synthesis of Metal Nanoparticles

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2293 ◽  
Author(s):  
Haja Tar ◽  
Tahani I. Kashar ◽  
Noura Kouki ◽  
Reema Aldawas ◽  
Bernadette Graff ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
High Performance ◽  
Gold Chloride ◽  
Au Nps ◽  
Glycol Diacrylate ◽  
Good Production ◽  
Iodonium Salt ◽  
Irradiation Process ◽  
Sem Analyses

The copper II complex (HLCuCl) carrying 2,4 dinitrophenylhydrazone (L) is synthesized and evaluated as a new photoredox catalyst/photoinitiator in combination with triethylamine (TEA) and iodonium salt (Iod) for the radical polymerization of ethylene glycol diacrylate during exposure to visible light using a photoreactor at 419 nm. The copper complex reactivity with TEA/Iod salt/gold chloride showed a good production and stability of gold nanoparticles. Finally, the high performance of Cu (II) complex for radical photopolymerization incorporating gold nanoparticles is provided. The photochemical mechanisms for the production of initiating radicals are studied using cyclic voltammetry. Polymer nanocomposites containing gold nanoparticles (Au NPs) in situ photogenerated during the irradiation process were prepared. The formation of Au NPs inside the polymer matrix was through UV–Vis and EDS/SEM analyses.

Basal Drainage System Response to Increasing Surface Melt on the Greenland Ice Sheet

Science ◽  
2013 ◽  
Vol 341 (6147) ◽  
pp. 777-779 ◽  
Author(s):  
T. Meierbachtol ◽  
J. Harper ◽  
N. Humphrey
Keyword(s):  
Conceptual Models ◽  
Ice Sheet ◽  
Drainage System ◽  
Greenland Ice Sheet ◽  
System Response ◽  
Mountain Glaciers ◽  
In Situ Observations ◽  
Key Aspects ◽  
Conduit Development

Surface meltwater reaching the bed of the Greenland ice sheet imparts a fundamental control on basal motion. Sliding speed depends on ice/bed coupling, dictated by the configuration and pressure of the hydrologic drainage system. In situ observations in a four-site transect containing 23 boreholes drilled to Greenland’s bed reveal basal water pressures unfavorable to water-draining conduit development extending inland beneath deep ice. This finding is supported by numerical analysis based on realistic ice sheet geometry. Slow meltback of ice walls limits conduit growth, inhibiting their capacity to transport increased discharge. Key aspects of current conceptual models for Greenland basal hydrology, derived primarily from the study of mountain glaciers, appear to be limited to a portion of the ablation zone near the ice sheet margin.

scholarly journals Mass balance of the Lambert Glacier–Amery Ice Shelf system, East Antarctica: a comparison of computed balance fluxes and measured fluxes

2000 ◽  
Vol 46 (155) ◽  
pp. 561-570 ◽  
Author(s):  
Helen A. Fricker ◽  
Roland C. Warner ◽  
Ian Allison
Keyword(s):  
Mass Balance ◽  
Drainage System ◽  
Radar Altimeter ◽  
Drainage Basins ◽  
Ice Shelf ◽  
Amery Ice Shelf ◽  
Ice Sheet Mass Balance ◽  
Lambert Glacier ◽  
Lambert Glacier Basin

AbstractWe combine European Remote-sensing Satellite (ERS-1) radar altimeter surface elevations (Fricker and others, 2000) with six different accumulation distributions to compute balance fluxes for the Lambert Glacier–Amery Ice Shelf drainage system. These interpolated balance fluxes are compared with fluxes derived from in situ measurements of ice thickness and velocity at 73 stations of the Lambert Glacier basin traverse and at 11 stations further downstream, to assess the system’s state of balance. For the upstream line we obtain a range of imbalance estimates, from −23.8% to +19.9% of the observed flux, reflecting the sensitivity to the accumulation distributions. For some of the accumulation distributions the imbalance estimates vary significantly between different parts of the line. Imbalance estimates for the downstream line range from −17.7% to +70.2%, with four of the estimates exceeding +30%, again reflecting the sensitivity of the result to input accumulation, and strongly suggesting that the mass balance of the region between the two lines is positive. Our results confirm the importance of accurate estimates of accumulation in ice-sheet mass-balance studies. Furthermore, they suggest that it is not possible to accurately determine the state of balance of large Antarctic drainage basins on the basis of currently available accumulation distributions.

Microgeographical Patterns of Allozyme Variation in Casuarina cunninghamiana Miq Within and Between the Murrumbidgee and Coastal Drainage Systems

1989 ◽  
Vol 37 (2) ◽  
pp. 181 ◽  
Author(s):  
NJ Moore ◽  
GF Moran
Keyword(s):  
Genetic Diversity ◽  
Large Population ◽  
Drainage System ◽  
Allozyme Variation ◽  
Distance Measures ◽  
Drainage Systems ◽  
Casuarina Cunninghamiana ◽  
Total Genetic Diversity ◽  
Geographic Clustering

Within the Murrumbidgee drainage system, 100 seedlings from each of 14 populations of Casuarina cunninghamiana were assayed for their allozyme genotypes at 14 loci. The levels of genetic variation were fairly similar in all populations. There was no geographic clustering of populations based on genetic distance measures. Only 3.8% of the total genetic diversity could be apportioned among populations within the drainage system. In six additional populations, branchlets from 50 trees per population were assayed for their allozyme genotypes at 27 loci. Three populations were from the Murrumbidgee drainage system and each of the others from a different coastal drainage. The mean expected heterozygosities for coastal and inland zones were 0.139 and 0.093 respectively. Of the total genetic diversity 10.7% could be apportioned among the four drainages. The results of this study suggest that for in situ conservtion of C. cunninghamiana within a region, more emphasis should be placed on conserving one large population from each major drainage system rather than a number of populations within one or two drainage systems.

scholarly journals Architecture in the public space – streets and squares under the conditions of urban globalization

2020 ◽  
Vol 16 (3) ◽  
pp. 50-57
Author(s):  
Dariusz Gaweł
Keyword(s):  
Public Space ◽  
Field Research ◽  
Public Spaces ◽  
The Public ◽  
New Public ◽  
The World ◽  
Build Environment

This article is the result of the research carried out by the author in creating new public spaces and shaping contemporary urban-forming trends in the conditions of globalization. In his research (through literature criticism and in situ field research) the author analyzes selected contemporary architectural realizations in Poland over the last decades, comparing them with similar works around the world, assessing their impact on shaping the cities’ build environment. The comparison is made through the analysis of such factors as: the construction of the form, elements of architecture and construction affecting the location, visibility, perception and created relations between the building and the surroundings.

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