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[en] In a clap-raw silk the contents the humidity makes 30 and more than percents. For draining of a damp clap-raw silk the hot air-heat-carrier with temperature in 363....573 K. But the present job is applied are investigated process draining of a clap-raw silk of a selection version Gissar, with degree of humidity 7.68 and 11.60%
[en] By experimentally at high-frequency bridge method on dependence of a tangent of a corner of dielectric losses of soil fom humidity and frequency of an electromagnetic field are investigated. In air-dry samples of soils the size of the most probable time of a relaxation and its maximum is established. It is shown that in the field of gravitational humidity, in the soil sample, at a maximum of a tangent of a corner of dielectric losses through conductivity will be veiled, i.e. obviously is not shown. As a result of the received data it is established that in the field of the adsorbed soil moisture the spectrum of time of relaxation is characterized by the wide strip reflecting heterogeneity of its dielectric properties. All this is offered to be used at designing of delkometric hydrometers and measurement of soil humidity
[en] A study is made regarding the nature and the amount of condensed tannin which can extract of bark from 11 tree species present in Costa Rica: guanacaste (Enterolobium cyclocarpum), cork oak (Licania arborea), jobo (Spondias mombin), pochote (Pachira quinata), loquat (Manilkara chicle), almond (Andira inermis), oak (Tabebuia rosea), cedar (Cedrela odorata), cenizaro (Samanea saman), pine (Pinus caribaea) and cypress (Cupressus lusitanica). The cortex samples were prepared, dried and extracted with ethanol. The ethanolic extracts were analyzed for condensed tannin content through the number of Stiasny, and characterized by infrared spectroscopy (FT-IR). The species with the highest proportion of extracted material were: guanacaste (9.5841% w/w), pochote (15.0066% w/w), pine (19.3400% w/w) and cypress (10.5300% w/w). The extracts with a higher proportion of condensed tannins have been: cork oak (61.9% w/w), jobo (66.1% w/w), pochote (72.8% w/w), loquat (50.5% w/w), cedar (72.7% w/w) and pine (70.7% w/w). (author)
[es]Un estudio es realizado sobre la naturaleza y la cantidad del tanino condensado que se puede extraer de la corteza de 11 especies arboreas presentes en Costa Rica: guanacaste (Enterolobium cyclocarpum), alcornoque (Licania arborea), jobo (Spondias mombin), pochote (Pachira quinata), nispero (Manilkara chicle), almendro (Andira inermis), roble (Tabebuia rosea), cedro (Cedrela odorata), cenizaro (Samanea saman), pino (Pinus caribaea) y cipres (Cupressus lusitanica). Las muestras de corteza han sido preparadas, secadas y extraidas con etanol. Los extractos etanolicos se han analizado para determinar el contenido de taninos condensados a traves del numero de Stiasny, y se han caracterizado mediante espectroscopia infrarroja (FT-IR). Las especies con mayor proporcion de material extraido han sido: guanacaste (9.5841% m/m), pochote (15.0066% m/m), pino (19.3400% m/m) y cipres (10.5300% m/m). Los extractos con una mayor proporcion de taninos condensados han sido: alcornoque (61.9% m/m), jobo (66.1% m/m), pochote (72.8% m/m), nispero (50.5% m/m), cedro (72.7% m/m) y pino(70.7% m/m). (autor)
[en] 8,500 archived radiographs were assessed for predominant fault developed within the archival period of five years. 4,625 radiographs representing 54.4 per cent were of poor quality. 'Hypo' stain (brownish discoloration) was the single largest contributor to poor archival quality (74 per cent, n = 3410) and appeared on radiographs stored even under a year. However, thiosulphate retention in film, a major cause of 'hypo' stain was found to be within acceptable limits (0.01 - 0.02 gm m-2) in most centres (85 per cent, n 846) due to good darkroom practices but no significant differences were noted in the level among the hospital/centres (p > 0.5). A linear regression analysis shows dependence of hypo stain formation on the physical conditions of temperature and humidity of the film libraries, with the former being a stronger causative factor. It is suggested that the high temperatures particularly, mean range - 24.5-32 degree C and high relative humidities (68-83 per cent) of the film library facilities characteristic of tropical climate, are responsible for the early onset of hypo stain in this study. Manual processing could be adopted where automatic method is unattainable but library facilities for archiving radiographs in the tropics should be air-conditioned. This is considered to be cost effective when compared with possible litigations and loss of teaching and review radiographs. Copyright (1998) Australian Institute of Radiography
[en] Fatigue crack growth in the low growth regime has been investigated by a new method called cyclic condensation environment. Using this method a growing crack is cyclically exposed to environment with high and low humidity. This variation causes the formation of a periodic pattern on the fracture surface called beach marks (BM). These markings give information about the successive position of the crack front. The formation of beach marks is directly related to the crack growth rate and they form when the growth rate is low and stop forming when the growth rate increases. This method have been used to study crack growth in different aluminium alloys in regions where crack growth rate is low, at the initiation zone of short cracks, near the threshold of long cracks and in the overload affected region. The mechanisms of beach mark formation is the same in all materials and in all three regions. The microscopic crack growth rate obtained from beach mark spacings gives a good correspondence with the macroscopic growth data obtained from crack length measurements. The beach mark appearance indicates that crack growth occurs in a continuous stepwise manner due to environmental changes. The mechanism of crack growth in the post-overload region is the same as in the initiation zone of a crack. The beach markings indicate that the crack growth after an overload occurs by an instantaneous retardation of the growth rate and a reinitiation of the crack along the crack front. The materials used in this investigation are 7075-T651, 8090-T851, 2024-T3, and 7075 aluminium glass fibre epoxy laminate (GLARE 1). The specimen types used are unnotched, compact tension (CT) and centre crack tension (CCT). The test were carried out at stress ratios 0.75 and 0.1 and frequencies 1-10 Hz. (au)
[en] Steel is a very versatile metallic material and widely used in modern life. Unfortunately, this material is prone to the phenomenon of corrosion and over time, can contribute to the failure of the product. In order to minimize this process, different types of coatings are used, due to their efficiency, economy and ease of application. The degradation of the film applied to steel by atmospheric agents is the result of the combination of various environmental factors, due to the highly destructive cyclic variations. The present work intends to determine the existence of significant statistical differences in the thickness distribution of coating in duplex systems (Fe/Zn/Paint), before and after conducting the humidity and temperature test with condensation in a constant atmosphere, from different tests carried out in the Stat graphics Centurion software. The influence of the preset conditions on the coating thickness before and after the test was demonstrated was demonstrated. These values were found in a suitable interval to guarantee the resistance to corrosion, not showing visible deterioration in the surface of the analyzed specimens.
[es]El acero es un material metálico muy versátil y ampliamente utilizado en la vida moderna. Desafortunadamente, este material está propenso al fenómeno de la corrosión y el pasar del tiempo, puede contribuir a la falla del producto. Para lograr minimizar este proceso se utilizan diferentes tipos de recubrimientos, debido a su eficacia, economía y facilidad de aplicación. La degradación de la película aplicada sobre el acero por los agentes atmosféricos es resultado de la combinación de diversos factores ambientales, debido a las variaciones cíclicas altamente destructivas. El presente trabajo pretende determinar la existencia de diferencias estadísticas significativas en las distribuciones del espesor de recubrimiento en sistemas dúplex (Fe/Zn/Pintura), antes y después de realizado el ensayo de humedad y temperatura con condensación en atmósfera constante, a partir de diferentes pruebas realizadas en el software Statgraphics Centurion. Se demostró la influencia de las condiciones prefijadas sobre el espesor de recubrimiento antes y después de realizado el ensayo. Dichos valores se encontraron en un intervalo adecuado para garantizar la resistencia a la corrosión, no evidenciándose deterioro visible en la superficie de las probetas analizadas.
[en] Dam basin agriculture consists in planting the gentle slopes of the dams as they are uncovered by receding waters. Crops use only soil water in their production cycle which occurs during the dry season. Since data on the water dynamics of dam basin agriculture in Northeast Brazil have not been published, a water balance study was established in a bare soil plot in the basin of Flocos dam, municipality of Tuparetama, PE (7 deg 36' S and 37 deg 18' O). The plot was equipped with one neutron probe access tube, one piezometer and tensiometers at different soil depths. Humidity was measured with a Nardeaux-20 neutron probe. Rainfall and class A tank evaporation were measured in a nearby micro-meteorological station. The water balance was performed for the top 30 cm soil layer, along 67 days (September 29 to December 5, 1998) which were divided in seven sub-periods. Soil water content indicated three time intervals with different soil water dynamics. For the complete period, soil water content decreased 53.9 mm and average daily evaporation and reference evaporation were 4.3 and 7.9 mm, respectively. (author)
[en] The soil moisture has a significant effect in the rates of N mineralization, being observed large values when the moisture is close to the Field Capacity. This work aimed to evaluated the influence of the soil moisture in the gross rates of N mineralization in a TRE clay soil. It was sampled cores of soil, with pvc rings. A randomized design with five treatments and four replications was used: T1- constant soil moisture of 9% (w/w; water mass for soil mass); T2 - constant soil moisture of 14% (w/w); T3 - constant soil moisture of 28% (w/w); T3 - constant soil moisture of 19% (m/m); T4 - constant soil moisture of 23% (w/w) and T5 - moisture of 28% (w/w). The gross rates of N mineralization for time period of 0-5 days were 0,31; 1,81; 1,66; 3,19 and 2,04 mg kg -1 day -1 and for the interval of time of 0-10 days were 0,33; 0,96, 0,96, 0,94 and 1,17 mg kg -1 day-1, respectively, for the treatments T1; T2; T3; T4 and T5. It was verified that the gross N mineralization was influenced by water content of soil. (author)
[en] A new technique for measuring cloud liquid water, mean droplet radius, and droplet number density is outlined. The technique is based on simultaneously measuring Raman and Mie scattering from cloud liquid droplets using a Raman lidar. Laboratory experiments on liquid microspheres have shown that the intensity of Raman scattering is proportional to the amount of liquid present in the spheres. This fact is used as a constraint on calculated Mie intensity assuming a gamma function particle size distribution. The resulting retrieval technique is shown to give stable solutions with no false minima. It is tested using Raman lidar data where the liquid water signal was seen as an enhancement to the water vapor signal. The general relationship of retrieved average radius and number density is consistent with traditional cloud physics models. Sensitivity to the assumed maximum cloud liquid water amount and the water vapor mixing ratio calibration are tested. Improvements to the technique are suggested. (c) 1999 American Geophysical Union
[en] Present article is devoted to durability of waveguide fibers at cyclic change of loading, temperature and humidity. The mounting scheme and loading of sample is presented. The dependence of glass fiber durability on number of thermal cycles at various humidity rates was considered. The dependence of number of cycles on maximal loading at cyclic temperature change was studied.