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Effect of Arsenic (III) on the Denitrification Process Presented in 12 th International Conference on Integrated Diffuse Pollution Management (IWA DIPCON 2008). Research Center for Environmental and Hazardous Substance Management (EHSM) Effect of Arsenic
No full textAbstract A sequencing batch reactor (SBR) was operated to develop denitrifying bacteria that had a mean specific denitrification rate of 0.11 g NO 3 --N/gVSS/day. Another system (an anaerobic digester) was operated to generate volatile fatty acids (VFAs) with the effluent concentration being measured to be 5655 876 mg/L as acetic acid. Using the denitrifying biomass developed in the SBR and VFAs generated in the digester as an external carbon source, a series of denitrification batch tests were conducted. The denitrification batch reactors were spiked with N
Analysis of HBT Behavior After Strong Electrothermal Stress
No full textAbstract-We present two-dimensional simulations of onefinger power InGaP/GaAs Heterojunction Bipolar Transistors (HBTs) before and after both electrical and thermal stress aging. It is well known that GaAs-HBTs with InGaP emitter material can be improved with respect to reliability if the emitter material covers the complete p-doped base layer forming outside the active emitter the so-called InGaP ledge. We analyze the influence of the ledge thickness and of of the surface charges on the device performance and its impact on reliability. The possibility t o explain device degradation mechanisms by means of numerical simulation is of high practical importance
Electron Multiplying CCDs
Get PDFElectron multiplying CCD (EMCCD) technology has found important initial applications in low light surveillance and photon starved scientific instrumentation. This paper provides a description of the technology and discusses the attributes of the EMCCD which may make it useful for other detectors, particularly those which are photon starve
Global welfare comparisons
Get PDFAbstract To provide a normative foundation for transfers between different economies, one needs information on their "per capita welfare". This paper considers various methods for doing this. The main conclusion is that such global welfare comparisons are more informationally demanding than usually thought. Moreover, the ranking of methods is opposite as for local (e.g., over-time) comparisons, with real comprehensive per capita NNP being the least impractical method. The lesson is that global welfare comparison should be performed with great care. The comparisons must be made in local real prices calculated according to "purchasingpower-parity", where non-traded environmental amenities play an important role
PROGRESS REPORT ON DEVELOPMENT OF NOVEL ULTRAFAST MID- IR LASER SYSTEM*
Get PDFAbstract Of particular interest to X-ray FEL light source facilities is Enhanced Self-Amplified Spontaneous Emission (ESASE) technique. Such a technique requires an ultrafast (20-50 fs) high peak power, high repetition rate reliable laser systems working in the mid-IR range of spectrum (2µm or more). The approach of this proposed work is to design a novel Ultrafast Mid-IR Laser System based on optical parametric chirped-pulse amplification (OPCPA). OPCPA is a technique ideally suited for production of ultrashort laser pulses at the center wavelength of 2 µm. Some of the key features of OPCPA are the wavelength agility, broad spectral bandwidth and negligible thermal load. This paper reports on the progress of the development of the Ultrafast Mid-IR Laser System
Nucleon Axial Charge in Full Lattice QCD
Get PDFThe nucleon axial charge is calculated as a function of the pion mass in full QCD. Using domain wall valence quarks and improved staggered sea quarks, we present the first calculation with pion masses as light as 354 MeV and volumes as large as 3:5 fm 3 . We show that finite volume effects are small for our volumes and that a constrained fit based on finite volume chiral perturbation theory agrees with experiment within 7% statistical errors
Based on observations obtained with VISTA at the Paranal Observatory under programme ID 179
Get PDFABSTRACT We present results based on Y JK s photometry of star clusters in the Large Magellanic Cloud (LMC), distributed throughout the central part of the galaxy's bar and the 30 Doradus region. We analysed the field-star decontaminated colour-magnitude diagrams of 313 clusters to estimate their reddening values and ages. The clusters are affected by a mean reddening of E(B − V ) ∈ [0.2, 0.3] mag, where the average internal LMC reddening amounts to ∼ 0.1-0.2 mag. The region covering 30 Doradus includes clusters with reddening values in excess of E(B − V ) = 0.4 mag. Our cluster sample spans the age range 7.0 log(t yr −1 ) < 9.0, represents an increase of 30 per cent in terms of the number of clusters with robust age estimates and comprises a statistically complete sample in the LMC regions of interest here. The resulting cluster frequencies suggest that the outermost regions of the LMC bar first experienced enhanced cluster formation -log(t yr −1 ) ∈ [8.5, 9.0] -before the activity proceeded, although in a patchy manner, to the innermost regions, for log(t yr −1 ) < 7.7. Cluster frequencies in the 30 Doradus region show that the area is dominated by very recent cluster formation. The derived star-formation frequencies suggest that the cluster and field-star populations do not seem to have fully evolved as fully coupled systems during the last ∼ 100 Myr
RESEARCH ON THE IMPACT OF ICTS ON THE LOCATION AND SPATIAL DEVELOPMENT OF FIRMS
Get PDFThis article resulted out of primary data produced on the basis o