ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (92,570)
  • Springer  (92,570)
  • 2010-2014  (92,570)
  • Geosciences  (87,341)
  • Technology  (6,958)
Collection
  • Articles  (92,570)
Source
Publisher
Years
Year
Journal
Topic
  • 1
    facet.materialart.
    Unknown
    Mechanical and Durability Behaviour of Structural Lightweight Concrete Produced with Volcanic Scoria (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: In this paper, the mechanical and long-term durability behaviour of structural lightweight concrete (LWC) produced with natural lightweight scoria aggregate (LWSA) from the Azores is analysed. Among the properties studied are the compressive and tensile strength, modulus of elasticity, shrinkage, capillary absorption, carbonation and chloride resistance. To this end, a comprehensive experimental study was carried out on different concrete compositions involving common and high-performance structural concrete produced with coarse or coarse and fine volcanic scoria aggregate. Generally, all the mechanical properties worsened with the incorporation of LWSA. It is concluded that the most efficient LWC with LWSA can attain compressive strength up to about 35 MPa. On the other hand, the production of LWC of more than 50 MPa implies a marked reduction in compressive strength for a small reduction in density. The long-term shrinkage increased with the replacement of normal-weight aggregate by LWA and was higher when coarse and fine scoria were used. However, the early age shrinkage can be counterbalanced by the internal curing effect provided by LWSA. The capillary absorption, chloride and carbonation resistance were affected by the high porosity of LWSA. The absence of the outer shell in scoria aggregate and the surface effects during tests can partly explain the lower performance of the LWC. Nevertheless, it is shown that LWC with scoria can be durable, and even for low- to moderate-strength LWC the corrosion induced by carbonation may not be relevant.
    Print ISSN: 1319-8025
    Electronic ISSN: 2191-4281
    Topics: Natural Sciences in General , Technology
    Published by Springer on behalf of The King Fahd University of Petroleum & Minerals.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Contamination assessment and potential human health risks of heavy metals in Klang urban soils: a preliminary study (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: Urban areas with rapid industrial development have major impacts on environmental soil quality. This study was carried out to determine contamination assessment of heavy metal concentration of urban soil from Klang district (Malaysia). Health risk assessment was used to determine potential health risks (carcinogenic and non-carcinogenic risks) in both adults and children. Moreover, this study was also used to identify the most significant contaminant and exposure pathway with regard to Klang urban soil. Mean bioavailability of heavy metal concentrations were found in the order of Fe (6.65 mg/kg) 〉 Zn (5.61 mg/kg) 〉 Cu (2.96 mg/kg) 〉 Co (0.22 mg/kg) 〉 Cd (0.14 mg/kg) 〉 Pb (0.11 mg/kg) 〉 Cr (0.10 mg/kg). Maximum values of Cd (0.64 mg/kg), Cu (52.14 mg/kg) and Pb (9.18 mg/kg) have exceeded some guidelines and standard values. Study findings showed that total carcinogenic risks values of Cd, Cr and Pb are more than incremental lifetime (1.0E-05). This indicates the likehood of having cancer threat for adults and children. While for total non-carcinogenic risk, none of the heavy metals (Co, Cr, Cu, Pb and Zn) showed Hazard Index values more than one indicating there is no any potential non-carcinogenic risks for adults and children in study area. From this study, Cd is the most significant contaminant as maximum concentration value has exceeded soil guidelines and potential to have carcinogenic risks to adults and children. Pathway order for both carcinogenic and non-carcinogenic risks is ingestion 〉 dermal 〉 inhalation where ingestion pathway contributed the most to potential health risks involving urban soil of Klang.
    Print ISSN: 1866-6280
    Electronic ISSN: 1866-6299
    Topics: Geosciences
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Effect of Coriolis Force on Bénard–Marangoni Convection in a Rotating Ferrofluid Layer with MFD Viscosity (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: The simultaneous effect of Coriolis force due to rotation and magnetic field dependent (MFD) viscosity on the onset of Bénard-Marangoni convection in a horizontal ferrofluid layer in the presence of a uniform vertical magnetic field is studied. The lower boundary is rigid while the upper free boundary is open to the atmosphere and at which the temperature-dependent surface tension effect is allowed for. The Galerkin technique is employed to extract the critical stability parameters numerically. The results show that the onset of Bénard-Marangoni ferroconvection is delayed with an increase in the MFD viscosity parameter Λ, Taylor number T a , magnetic susceptibility χ and Biot number B i but opposite is the case with an increase in the value of magnetic number M 1 and nonlinearity of fluid magnetization M 3 . Further, increase in M 1 , M 3 and decrease in Λ, T a , χ and B i is to decrease the size of the convection cells. Comparisons of results between the present and the existing ones are made under the limiting conditions and good agreement is found.
    Print ISSN: 0938-0108
    Electronic ISSN: 1875-0494
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Natural Sciences in General , Technology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Free Surface Deformation of Thermo-Solutocapillary Convection in Axisymmetric Liquid Bridge (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: Steady thermo-solutocapillary convection in axisymmetric liquid bridge with dynamic free surface is numerically studied in the absence of gravitational effects. The upper and lower disks of liquid bridge maintain at constant temperature and solute concentration. The deformable free surface is obtained by Level set method. Numerical simulations are carried out for Prantle number Pr = 1, Capillary number Ca = 0.1, Marangoni number 1 ≤ Ma ≤ 100, and thermal to solutal Marangoni number ratio −10≤R σ ≤ 0.1. The results show that there are three modes of free surface deformation in thermo-solutocapillary convection under low Marangoni number: 1) as −10≤R σ 〈−1, the free surface bulges out near the lower disk and bulges in near the upper disk; 2) as R σ =−1 the free surface bulges out near the lower and upper disks and bulges in at the central region of the liquid bridge; 3) as −1R σ ≤−0.1, the free surface bulges out near the upper disk and bulges in near the lower disk. Moreover, the effect of Marangoni number on free surface deformation also is discussed.
    Print ISSN: 0938-0108
    Electronic ISSN: 1875-0494
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Natural Sciences in General , Technology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    A New Highly Accurate CMOS Current-Mode Four-Quadrant Multiplier (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: A new CMOS current-mode four-quadrant analog multiplier is presented. The design is based on the square-difference approach using short-channel MOSFETs operating in saturation region and a rectifier. The squaring circuit used is free of error due to carrier mobility reduction and hence an accurate multiplier is achieved. Tanner T-spice is used to confirm the functionality of the proposed design using 0.18μm TCMS CMOS process technology. Simulation results shows that the relative error is 1.8% and –3dB frequency is 230MHz.
    Print ISSN: 1319-8025
    Electronic ISSN: 2191-4281
    Topics: Natural Sciences in General , Technology
    Published by Springer on behalf of The King Fahd University of Petroleum & Minerals.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Determining and plugging the groundwater recharge channel with comprehensive approach in Siwan coal mine, North China coal basin (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: In North China coal basin, there is an accident: the water which comes from Ordovician system aquifer (O 2 ) discharges into underground coal mines. The coal mining operations would be seriously threatened by this kind of accident. In order to solve this problem, the characteristics of various exploration methods have been discussed. A comprehensive approach involving hydrogeological analysis, geophysical prospecting, hydrogeological drilling, and hydrogeological field test was proposed to explore the groundwater recharge channel. A typical North China coal mine, Siwan coal mine, was taken as an example. The groundwater recharge channel on F 8 fault was precisely explored and plugged. After the curtain grouting, the water discharge rate per unit of drawdown was dropped from 12.0 to 7.0 m 3 /(h m), and the water yield in coal mine was reduced by 600 m 3 /h. A much safer condition can be provided for Siwan coal mine, avoiding the waste of water resource.
    Print ISSN: 1866-7511
    Electronic ISSN: 1866-7538
    Topics: Geosciences
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    A Case Study of Seismic Hazard Analysis at Al-Tajiat and Al-Zawraa Stadiums in Baghdad/Iraq Region (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: The purpose of this study was to conduct seismic hazard analysis for Al-Tajiat and Al-Zawraa stadiums using probabilistic and deterministic approaches. The stadiums of Al-Tajiat and Al-Zawraa are located at latitude of \({33^{\circ}}\) 25ʹ25.80ʺN, longitude of \({44^{\circ}}\) 17ʹ9.28ʺE and latitude of \({33^{\circ}}\) 20ʹ39ʺN, longitude of \({44^{\circ}}\) 22ʹ5.81ʺE, respectively. To assess the seismic hazard, the region was divided into five seismic sources, and the seismic parameters were calculated for each selected seismic source. According to the results obtained from probabilistic seismic hazard analysis, the maximum horizontal accelerations on bedrock for return periods of 75, 475, and 2,475 years are equal to 0.06, 0.12, and 0.21 g, respectively. The result of deterministic seismic hazard assessment proves that the maximum horizontal and vertical acceleration on bedrock are 0.31 and 0.16 g, respectively. In order to analyze the response of structures against calculated acceleration, studies related to response spectrum and design spectrum have been carried out based on statistical analysis of appropriate time histories. The computer program Equivalent linear Earthquake Response Analysis was used to process the selected records and to consider the effect of soil conditions. Design spectrum has also been presented based on the response spectrum of the selected time histories and then was compared with the corresponding ones in UBC 1997 and ISIRI 2800 codes. The comparison shows that the presented design spectrum is more conservative than the results provided by the above codes.
    Print ISSN: 1319-8025
    Electronic ISSN: 2191-4281
    Topics: Natural Sciences in General , Technology
    Published by Springer on behalf of The King Fahd University of Petroleum & Minerals.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Dependence of Turbulent Velocities on Wind Speed and Stratification (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: We examine the dependence of several turbulence quantities on the wind speed and stability using nocturnal data from the Shallow Cold Pool Experiment. The turbulent quantities (velocities) are defined in terms of the standard deviation of the horizontal and vertical velocity fluctuations, two different calculations of the friction velocity, and two turbulent velocities based on the heat flux. The dependence of the turbulent velocities on the wind speed shows a transition between the weak-wind regime of small slope and the stronger wind regime of larger slope, as found in previous studies. This transition occurs for all of the turbulent velocities examined and occurs for a wide range of averaging times. Although this study concentrates primarily on data over a flat surface above the valley, the transition also occurs at the other 18 stations that have non-zero local slopes up to about 10 %. At the same time, the relationship between the turbulence and the wind speed cannot be universal because of the influence of stratification and site-dependent non-stationarity in the weak-wind regime. The wind speed of the transition increases with increasing stratification at a rate that is an order of magnitude slower than that predicted by a constant transition bulk Richardson number. For the weakest winds, the impact of stratification is unexpectedly small.
    Print ISSN: 0006-8314
    Electronic ISSN: 1573-1472
    Topics: Geosciences , Physics
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Monitoring infiltration under a real on-site treatment system of domestic wastewater and evaluation of soil transfer function (Paris Basin, France) (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Description: The problem of evacuation of treated domestic wastewater has been investigated through a field study on a real undrained on-site treatment system (UOSTS). This system imposes a special mode of infiltration into the soil which is irregular. To characterize the hydraulic properties of this type of flow, soil texture, organic matter content and in situ saturated hydraulic conductivity (Ks) were measured for each 15 m 2 of soil under the bottom of the UOSTS. In addition, the variation of water table and rainfall and the evolution of soil moisture and matrix potential were monitored using the sensors implanted under the system. The mean of the measured Ks is 100 times higher than values deduced from empirical pedotransfer functions based on the soil matrix properties. The measured Ks varies greatly in the 15 m 2 area. Moreover, large and variable quantities of stone fragments (〉2 mm) were found in the soil samples. These results suggest that a heterogeneous flow may occur in the stony soil via the macropores which shortcut the soil matrix. Indeed, according to their position, a non-uniform reaction of the sensors to the infiltration of treated wastewater was observed. In addition, two daily periodic peaks of water consumption in the house have been detected by the water content and tensiometer probes, confirming that the saturation rate is controlled by infiltration and not the water table.
    Print ISSN: 1866-6280
    Electronic ISSN: 1866-6299
    Topics: Geosciences
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    A Case Study of Seismic Hazard Analysis at Al-Tajiat and Al-Zawraa Stadiums in Baghdad/Iraq Region (2014)
    Springer
    Details
    Publication Date: 2014-12-31
    Print ISSN: 1319-8025
    Electronic ISSN: 2191-4281
    Topics: Natural Sciences in General , Technology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...