Monitoring of Heavy Metals By Energy Dispersive X-Ray Fluorescence Spectrometry

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Fundamentals and salient features of a projected heavy metals monitoring system are discussed. Determination of mass concentrations is achieved by using a new dust emission monitor, consisting of a "Zero Pressure Probe" for isokinetic sampling, which is connected to a "Longitudinally Oscillating Band" mass detector. The thin dust layer, precipitated on the surface of heat resistant filter tapes could be analysed nondestructively by energy-dispersive X-ray fluorescence (EDXRF). Using a small portable EDXRF-system with radioisotope-excitation, quasi-continuous monitoring of particulate heavy metals (Cd, Hg, Pb, Cu, Sb, Zn, Sn) suspended in incinerator stack gases is expected to be feasible. Another application of EDXRF-analysis is the reported investigation of electrostatic precipitator ash (ESP-fly ash). Using the "Linear Multi-Elemental-Standard Addition Method" as a fast and simple routine technique, results are reported for the concentrations of Pb, Cd, Cu and Zn in fly ash samples which had been collected in different fields (hoppers) of the electrostatic precipitator

Testimony of Lawrence Z. Lorber on Behalf of the National Association of Manufacturers Before the Commission on the Future of Worker-Management Relations

Testimony_Lorber_092994.pdf: 91 downloads, before Oct. 1, 2020

Enhanced Post-Learning Memory Consolidation is Influenced by Arousal Predisposition and Emotion Regulation but Not By Stimulus Valence or Arousal

Emotionally arousing stimuli are more memorable than neutral ones and arousal induced after learning enhances later retrieval. However, there is as yet little study of how stimulus qualities might interact with induced arousal and how individual differences might influence the modulation of memory. Thus, the present study examined the effect of arousal induced after learning on memory for words that varied in both arousal and valence quality, as well as the influence of three individual differences factors that are known to influence arousal response: emotional suppression, emotional reappraisal, and arousal predisposition. Seventy-six adults (57 female) viewed and rated 60 words that normatively ranged from high to low in arousal and valence. Ten minutes later, they viewed a 3-min comedic or neutral video clip. Arousal induced after learning enhanced 1-week delayed memory, spanning the lengthy task without preference for word type or serial position, contrasting with reports of arousal effects interacting with stimulus qualities. Importantly, being predisposed to arousal led to greater enhancement of long-term memory modulation, while the use of emotional reappraisal, which reduces arousal responding, inhibited the ability of arousal to induce memory enhancement. Thus, individual differences that influence arousal responding can contribute to or interfere with memory modulation

An unsteady helicopter rotor: Fuselage interaction analysis

A computational method was developed to treat unsteady aerodynamic interactions between a helicopter rotor, wake, and fuselage and between the main and tail rotors. An existing lifting line prescribed wake rotor analysis and a source panel fuselage analysis were coupled and modified to predict unsteady fuselage surface pressures and airloads. A prescribed displacement technique is used to position the rotor wake about the fuselage. Either a rigid blade or an aeroelastic blade analysis may be used to establish rotor operating conditions. Sensitivity studies were performed to determine the influence of the wake fuselage geometry on the computation. Results are presented that describe the induced velocities, pressures, and airloads on the fuselage and on the rotor. The ability to treat arbitrary geometries is demonstrated using a simulated helicopter fuselage. The computational results are compared with fuselage surface pressure measurements at several locations. No experimental data was available to validate the primary product of the analysis: the vibratory airloads on the entire fuselage. A main rotor-tail rotor interaction analysis is also described, along with some hover and forward flight

Unsteady transition measurements on a pitching three-dimensional wing

Boundary layer transition measurements were made during an experimental study of the aerodynamics of a rectangular wing undergoing unsteady pitching motions. The wing was tested at chordwise Mach numbers between 0.2 and 0.6, at sweep angles of 0, 15, and 30 deg, and for steady state, sinusoidal, and constant pitch rate motions. The model was scaled to represent a full size helicopter rotor blade, with chord Reynolds numbers between 2 and 6 x 10(exp 6). Sixteen surface hot-film gages were located along three spanwise stations: 0.08, 0.27, and 0.70 chords from the wing tip. Qualitative heat transfer information was obtained to identify the unsteady motion of the point of transition to turbulence. In combination with simultaneous measurements of the unsteady surface pressure distributions, the results illustrate the effects of compressibility, sweep, pitch rate, and proximity to the wing tip on the transition and relaminarization locations

Airfoil stall penetration at constant pitch rate and high Reynolds number

The model wing consists of a set of fiberglass panels mounted on a steel spar that spans the 8 ft test section of the UTRC Large Subsonic Wind Tunnel. The first use of this system was to measure surface pressures and flow conditions for a series of constant pitch rate ramps and sinusoidal oscillations a Mach number range, a Reynolds number range, and a pitch angle range. It is concluded that an increased pitch rate causes stall events to be delayed, strengthening of the stall vortex, increase in vortex propagation, and increase in unsteady airloads. The Mach number range causes a supersonic zone near the leading edge, stall vortex to be weaker, and a reduction of unsteady airloads

Online monitoring of vinyl chloride polymerization in a microreactor using raman spectroscopy

A novel capillary-based microfluidic device has been designed to follow the vinyl chloride polymerization reaction. The use of a co-flow generation system enabled obtaining monodisperse vinyl chloride droplets within 200 µm in diameter, each one being considered as a polymerization reactor. During polymerization VCM droplets were visualized with a high speed camera. At the end of the reaction PVC grains were observed with a Scanning Electron Microscopy technique. Real-time non-invasive Raman measurement has been performed on stationary vinyl chloride monomer droplets and has provided values of effective reaction orders n and effective rate constants k. This microdevice allowed the investigation in difficult conditions (pressure, temperature) with a minimal amount of reagents and consequently under safe conditions

Regional Development Problems of Podravje

Novo oblikovani regionalni razvojni programi so nastali z namenom zmanjševanja regionalnih razlik in krepitve ekonomske in socialne kohezije, in naj bi zagotovili skladnejši regionalni razvoj slovenskega ozemlja. Z enakomernejšim razvojem bo Slovenija postala konkurenčnejša na skupnem evropskem trgu in v globalizacijskih procesih. Splošne regionalne razvojne značilnosti Slovenije kažejo, da obstajajo velike razlike na področju gospodarskega, socialnega in prostorskega razvoja posameznih območij. Med statističnimi regijami je Podravje opredeljeno kot območje s strukturnimi problemi in kot ekonomsko šibko ter socialno nestabilno območje s staro industrijsko strukturo in s pretežno agrarno usmeritvijo. Kako okrepiti splošni razvoj na obmejnem območju z Avstrijo in Hrvaško, preprečiti nadaljnjo socio-ekonomsko zaostajanje in zagotoviti trajnostni razvoj, predstavlja ključno strateško vprašanje Podravja v naslednjem desetletju.The newly designed regional development programs were formed with the intention of reducing regional differences and strengthening economic and social cohesion in order to ensure a more harmonious regional development of Slovenian territory. Due to the more proportionate development, Slovenia will become more competitive in the Common European Market as well as in globalisation processes. General regional developmental characteristics of Slovenia indicate the existence of considerable differences in the field of economic, social and spatial development between individual regions. Among statistical regions, the Podravje area is defined as the area having structural problems and being an economically weak and socially unstable territory with old industrial structure and predominantly agriculturally oriented. Strengthening general development in the border region with Austria and Croatia and preventing further socio-economic setback as well as ensuring sustainable development are the key strategic issues of the Podravje region in the next decade