Development of an Atmospheric Particle Dry Deposition Model

A model to predict the atmospheric dry deposition velocities of particles has been developed that is similar to a model developed for the prediction of particle deposition velocities in vertical pipes. The model correlates the particle deposition velocity (V_d ) with Stokes settling velocity (V _st), friction velocity (V*), dimensionless inertial deposition velocity (V ⁺ _di ), and dimensionless Brownian diffusion deposition velocity (V ⁺ _dd ). V ⁺ _di      

Time domain constrained H∞‐synthesis

Structured H_∞‐synthesis subject to time domain performance specifications is introduced. Our method allows to control trajectories of the linearized system and the underlying nonlinear dynamics simultaneously. A non‐smooth bundle optimization method for this class of programs is proposed and discussed. Our approach is tested against two benchmark studies: control of a rotational actuator to attenuate vibration noise, and control of a continuous crystallizer. Our algorithm gives a local convergence certificate and is suited for systems with large state dimension. Copyright © 2010 John Wiley & Sons, Ltd.     

Temperature and gas evolution during large scale outside storage of wood chips

The temperature and gas concentrations in a newly established pine-wood debris pile of 20?m×15?m×6?m in dimensions (approximately 400?tons of fresh weight material) were monitored for 150?days. Temperature was measured at ten different positions within the pile, while concentrations of CO₂, O₂, CO and CH₄ were taken at four different representative locations. The pile was characterized by a strong temperature increase within the first 10?C12?days of storage. Results of the gas analysis in this period suggest that the temperature increase was caused by microbial processes. In particular, reduced oxygen concentration and almost complete absence of methane indicate mainly aerobic respiration processes. Effects of weather conditions on the temperature/gas distribution and time evolution are also discussed in the paper.     

Characterization of atmospheric concentrations and partitioning of PAHs in the Chicago atmosphere

An intensive sampling program has been undertaken in the absence of precipitation at an urban site, Chicago, to characterize the atmospheric concentration and partitioning of PAHs. Two different sampling programs have been carried out with a large number of samples. Measured ambient concentrations of PAHs were classified as Land and Lake samples based on wind direction and back trajectory calculations. Differences in ambient concentrations of PAHs were observed between Land and Lake samples. The concentrations of PAHs when air originated over the Land were approximately two-four times higher than the concentrations measured when air originated over the Lake. It has been demonstrated that partitioning of PAHs shows a consistent difference between samples taken when wind came from off the land rather than off the water. This was most evident by more shallow slopes for Lake samples compared to the slopes for Land samples, when partition coefficient (K(p)) is plotted on a log-log scale vs. the subcooled liquid vapor pressure (P(L)(0)). Experimentally, determined K(p) values were compared with the results obtained using two different models, one based on absorption into aerosol organic matter and the other adsorption onto soot carbon. Experimental K(p) values generally agreed well with the soot+octanol based model predictions.     

Grief Processing and Deliberate Grief Avoidance: A Prospective Comparison of Bereaved Spouses and Parents in the United States and the People's Republic of China.

In this study, the authors measured grief processing and deliberate grief avoidance and examined their relationship to adjustment at 4 and 18 months of bereavement for 2 types of losses (spouse, child) in 2 cultures (People's Republic of China, United States). Three hypotheses were compared: the traditional grief work assumption, a conditional grief work hypothesis, and a view of grief processing as a form of rumination absent among resilient individuals. Although cultural differences in grief processing and avoidance were observed, the factor structure of these measures proved invariant across cultures. Consistent with the grief work as rumination hypothesis, both grief processing and deliberate grief avoidance predicted poor long-term adjustment for U.S. participants. Furthermore, initial grief processing predicted later grief processing in both cultures. However, among the participants in the People's Republic of China, neither grief processing nor deliberate avoidance evidenced clear psychological consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Integrating explicit path planning with reactive control of mobile robots using Trulla

This article describes and investigates a method of interleaving explicit path planning with reactive control. The Trulla all-paths planner computes an a priori set of optimal paths. Minor reactions to obstacles and terrain changes serve to switch the robot from the precomputed path to a new precomputed path, eliminating subgoal obsession. Major deviations suggest that the a priori map is significantly wrong; explicit replanning should be triggered to ensure continued progress of the robot. The dot product is used as the intrinsic measure of a major deviation. This methodology is particularly well-suited for computationally bound robots such as planetary rovers and robots operating in indoor environments with a large number of minor unmodeled obstacles.

The article describes the Trulla and dot product algorithms, and reports on experimental data collected from a mobile robot under representative scenarios. The method is compared to continuous and fixed frequency replanning under differing environments and robot velocities. The results show that the deferred replanning with the Trulla/dot product methodology produced actual paths similar to more frequent replanning in distance and time but with up to 100 times less computation. The reduced computation led to a 8.75% increase in distance traveled and 24% increase in travel time. In the presence of faulty sensor data, Trulla outperformed the other methods which radically changed the path back and forth due to spurious sensor readings.     

Corrected formula for the calculation of the electrical heart axis

Right brain damage results in a variety of cognitive and behavioural dysfunctions. Mutism however, has been described only with left or bihemispheric lesions involving the parietal lobe. We report an elderly man who had left faciobrachial monoparesis and concomitant mutism. His auditory-verbal comprehension was intact. MRI revealed a right parietal infarct involving the cortical and subcortical regions. Recovery from mutism during the course of treatment was abrupt and complete with no residual dysarthria. A possibility of diaschisis or impaired modulation of left hemispheric function due to right cerebral infarct, presenting as conversion reaction, is proposed for this rare association.     

In situ Profiles of Oxygen Diffusion in SrTiO3: Bulk Behavior and Boundary Effects

Diffusion profiles have been recorded in situ and evaluated using an optical technique. In this way, bulk diffusion coefficients have been reliably and quantitatively measured. It is shown that the values agree with calculations without using adjustable parameters if the coupling of the diffusing species to internal redox changes of the dopants is accounted for. Measurements on single crystals and on bicrystals with and without crack formation provide worthwhile information on the influence of free relaxed surfaces, freshly produced (crack) surfaces, and grain boundaries on the surface reaction rate and diffusional process. The inward diffusion of oxygen via crack surfaces is characterized by enhanced diffusion coefficients.     

Liquid Membrane Permeation with Supported Liquid Membranes and their Application in Li-ion Battery Recycling

A study of liquid membrane permeation with supported flat sheet membranes was performed. The goal of the project was to improve the stability and accuracy of supported liquid membranes (SLM) by avoiding short circuiting of phases with technical measures. Mass transfer and stability tests were carried out with the test system Zn²⁺|HDEHPA|H⁺. The effect of operation conditions on mass transfer and accumulation of Zn²⁺ in the stripping phase was investigated. A process for the recycling of Li-ion batteries including two SLM separation stages was developed. Experimental findings confirmed the feasibility of this process, yielding high purity streams of aqueous copper, cobalt, and lithium solutions.