Electromagnetic Pulse Sounding for Surveying Underground Water

This project supported in part by the Office of Water Resources Research U. S. Department of the Interior Washington, D. C. under Project B-028-OHIOA number of approaches have been explored for measuring the water content of soil electrically. In contrast with traditional measurements, which utilize electric currents at DC or at specific frequencies, our techniques have been based on the transmission and reflection of sharp, regularly repeated pulses. Such pulse measurements can be shown to be equivalent to measuring the electrical properties at all frequencies in a very wide band, and therefore the possibility of extracting the desired information is much greater than with single-frequency measurements. Because the information content of the signal is great, data processing can be used to extract those features which relate most directly to moisture content and reject those which appear to depend more on soil inhomogenieties. For example, it was found that the attenuation in the frequency band of approximately 10 to 20 MHz had a much higher correlation with soil moisture than that in other frequency bands for the actual field conditions under which our measurements were made. This information content increase is obtained by means of sophisticated research equipment. The measurements reported herein were made and processed under real-time computer control. They include the signal scattered from known buried targets, transmission measurements through the ground, and the measurement of reflections in a coaxial test cell, all with pulses containing very wide frequency bands. The results are encouraging in that definite correlations with moisture were found. Unfortunately the one-year time limitation of this effort, much of it spent in instrumentation development, was insufficient to allow testing these correlations quantitatively over extended time periods or in a variety of locations. Thus the techniques must be evaluated at present as promising, but not fully proven. It should be noted that, while the research system to obtain this information is complex, field equipment based on these techniques need not be unduly complicated or expensive. Once the features relating to moisture content under the greatest variety of field conditions are identified, means for extracting this information more simply should be devised. This is proposed as the objective for continuation of this effort.Summary -- Introduction -- 1. The Measuring System -- 2. Data Processing -- 3. Underground Moisture Content Monitoring by Measurement of Buried Target Signatures -- 4. Sampled Moisture Conditions -- 5. Underground Propagation Experiment -- 6. Reflection Measurements on Soil Samples in a Vertical Coaxial Test Cell -- 7. Propagation Calculations -- Conclusions -- Recommendations -- References -- Appendix I - Transmission Measurements using a Buried Antenn

Multiscale Photon Based In Situ and Operando Spectroscopies in Time and Energy Landscapes

Following catalytic reactions, in situ and operando are now the focus of a number of dedicated experiments at light sources which have been developed to track the electronic and molecular structural dynamics of catalysts. The challenges for this goal are two fold first, the development of spectroscopic tools in the energy domain and time domain is required. The photocatalytic processes have early dynamics of tens of femtoseconds, while further reaction takes seconds, minutes, and even hours. Second, a combination of tools to probe processes not only in solids, but also in solutions and at interfaces, is now needed. In this special issue, we present recent developments at the synchrotron facility BESSY II using photon energy from the infrared and extreme ultraviolet up to the soft X ray regime for in situ and operando applications addressing these two major challenges. As this work is a result of contributions from several groups, each section will present the group s activities and related team members involve

Three-Dimensional Stochastic Off-Lattice Model of Binding Chemistry in Crowded Environments

Molecular crowding is one of the characteristic features of the intracellular environment, defined by a dense mixture of varying kinds of proteins and other molecules. Interaction with these molecules significantly alters the rates and equilibria of chemical reactions in the crowded environment. Numerous fundamental activities of a living cell are strongly influenced by the crowding effect, such as protein folding, protein assembly and disassembly, enzyme activity, and signal transduction. Quantitatively predicting how crowding will affect any particular process is, however, a very challenging problem because many physical and chemical parameters act synergistically in ways that defy easy analysis. To build a more realistic model for this problem, we extend a prior stochastic off-lattice model from two-dimensional (2D) to three-dimensional (3D) space and examine how the 3D results compare to those found in 2D. We show that both models exhibit qualitatively similar crowding effects and similar parameter dependence, particularly with respect to a set of parameters previously shown to act linearly on total reaction equilibrium. There are quantitative differences between 2D and 3D models, although with a generally gradual nonlinear interpolation as a system is extended from 2D to 3D. However, the additional freedom of movement allowed to particles as thickness of the simulation box increases can produce significant quantitative change as a system moves from 2D to 3D. Simulation results over broader parameter ranges further show that the impact of molecular crowding is highly dependent on the specific reaction system examined

SAXS signature of the lamellar ordering of ionic domains of perfluorinated sulfonic acid ionomers by electric and magnetic field assisted casting

At present, small angle X ray scattering SAXS studies of perfluorinated sulfonic acid ionomers PFSAs are unable to fully determine the true shape of their building blocks, as recent SAXS modelling predicts disk and rod like nanoionic domains as being equally possible. This scenario requires evidence based findings to unravel the real shape of PFSA building blocks. Herein, a SAXS pattern signature for a lamellar nanophase separation of the ionic domains of Nafion is presented, backed by mid and far infrared spectroscopy MIR and FIR and wide angle X ray scattering WAXS data of Nafion in different ionic forms, a broad range of ionic phase contents EW amp; 8764; 859 42 amp; 8198;252 g eq amp; 8722;1 and temperatures. The study indicates that the lamellar arrangement of the ionic domains is the most representative morphology that accounts for the physical properties of this ionomer. The lamellar SAXS reflections of Nafion are enhanced in electric and magnetic field aligned membranes, as confirmed by atomic force microscopy AFM . Electric and magnetic field assisted casting of Nafion allowed producing nanostructured and anisotropic films with the lamellas stacked perpendicularly to the field vector, which is the direction of interest for several applications. Such nanostructured Nafion membranes are bestowed with advanced optical and proton transport properties, making them promising materials for solar and fuel cell

Occurrence of polycyclic aromatic hydrocarbons, microplastics and biofilms in Alqueva surface water at touristic spots

Freshwater pollution is a huge concern. A study aiming to evaluate physico chemical characteristics, microbiota, occurrence of two groups of persistent environmental pollutants with similar chemical properties polycyclic aromatic hydrocarbons PAHs and microplastics MPs in Alqueva s surface water was performed during 2021. Water samples were collected at three spots related to touristic activities two beaches and one marina during the Winter, Spring, Summer and Autumn seasons. In addition, the presence of biofilms on plastic and natural materials stone, wood vegetal materials were assessed and compared. Water quality based on physicochemical parameters was acceptable with a low eutrophication level. PAHs concentration levels were lower than the standard limits established for surface waters by international organizations. However, carcinogenic compounds were detected in two sampling locations, which can pose a problem for aquatic ecosystems. PAHs profiles showed significant differences when comparing the dry seasons with the rainy seasons, with a higher number of different compounds detected in Spring. Low molecular weigh compounds, usually associated with the atmospheric deposition and petroleum contamination, were more prevalent. MPs were detected in all samples except one during the Winter season. The polymers detected were poly methyl 2 methylpropenoate , polystyrene, polyethylene terephthalate, polyamide, polypropylene, styrene butadiene, polyvinyl chloride and low high density polyethylene with the last being the most frequent. Biofilms were more often detected on plastics than on natural materials. In addition, biofilms detected on plastics were more complex with higher microbial diversity e.g., bacteria, fungi yeast and phytoplancton organisms and richer in extrapolymeric material. Based on morphological analysis a good agreement between microbiota and microorganism present in the biofilms was found. Among microbiota were identified microorganisms previously linked to plastic and PAHs detoxification suggesting the need for further studies to evaluate the viability of using biofilms as part of a green bioremediation strategy to mitigate water pollutio

Unified regression model of binding equilibria in crowded environments

Molecular crowding is a critical feature distinguishing intracellular environments from idealized solution-based environments and is essential to understanding numerous biochemical reactions, from protein folding to signal transduction. Many biochemical reactions are dramatically altered by crowding, yet it is extremely difficult to predict how crowding will quantitatively affect any particular reaction systems. We previously developed a novel stochastic off-lattice model to efficiently simulate binding reactions across wide parameter ranges in various crowded conditions. We now show that a polynomial regression model can incorporate several interrelated parameters influencing chemistry under crowded conditions. The unified model of binding equilibria accurately reproduces the results of particle simulations over a broad range of variation of six physical parameters that collectively yield a complicated, non-linear crowding effect. The work represents an important step toward the long-term goal of computationally tractable predictive models of reaction chemistry in the cellular environment

The Use of PRV-Bartha to Define Premotor Inputs to Lumbar Motoneurons in the Neonatal Spinal Cord of the Mouse

The neonatal mouse has become a model system for studying the locomotor function of the lumbar spinal cord. However, information about the synaptic connectivity within the governing neural network remains scarce. A neurotropic pseudorabies virus (PRV) Bartha has been used to map neuronal connectivity in other parts of the nervous system, due to its ability to travel trans-neuronally. Its use in spinal circuits regulating locomotion has been limited and no study has defined the time course of labelling for neurons known to project monosynaptically to motoneurons.Here we investigated the ability of PRV Bartha, expressing green and/or red fluorescence, to label spinal neurons projecting monosynaptically to motoneurons of two principal hindlimb muscles, the tibialis anterior (TA) and gastrocnemius (GC). As revealed by combined immunocytochemistry and confocal microscopy, 24-32 h after the viral muscle injection the label was restricted to the motoneuron pool while at 32-40 h the fluorescence was seen in interneurons throughout the medial and lateral ventral grey matter. Two classes of ipsilateral interneurons known to project monosynaptically to motoneurons (Renshaw cells and cells of origin of C-terminals) were consistently labeled at 40 h post-injection but also a group in the ventral grey matter contralaterally. Our results suggest that the labeling of last order interneurons occurred 8-12 h after motoneuron labeling and we presume this is the time taken by the virus to cross one synapse, to travel retrogradely and to replicate in the labeled cells.The study establishes the time window for virally-labelling monosynaptic projections to lumbar motoneurons following viral injection into hindlimb muscles. Moreover, it provides a good foundation for intracellular targeting of the labeled neurons in future physiological studies and better understanding the functional organization of the lumbar neural networks

Saving Big Bucks with Your Log Sheets

This paper speaks to a common problem in a lot of industrial and institutional boilerhouses. Most boilerhouses do an excellent job at collecting information. Circular chart recorders churn out pressures, temperatures, and flows for everything from steam to natural gas to city water consumption. If your facility is like most, this stuff all gets chucked into a drawer or file cabinet daily. Have you ever wondered why you collect and record what you do? What were people thinking when the existing logs were set up? This paper attempts to challenge the original thought process and hopes to evoke in you and your staff a renewed vision of what should be collected, how, and then what can be done with it. It seems that most "good old days" data collection efforts were centered around identifying equipment operability and reliability problems. If a line suddenly jumped off the chart, hopefully someone would notice and react in just the right way to keep the plant operating. However, 99% of the time when things change slightly over days or when things seem normal, no one gets excited about anything. This is because action points or things to care about (TCA's) for energy savings are few and far between. This paper hopes to help you define lots of energy cost-related TCA's. This is all about data mining. It's all about finding gold buried in what you thought was waste. This paper can't give you specifics. It can however point you to appropriate TCA concepts. TCA's must be individually tailored to a particular boilerhouse's equipment, people, needs, utility costs, maintenance patterns, and a number of other critical factors. The goal of this paper is not to define new and expensive data acquisition or control system projects, It is instead to show you how to develop systems that only require paper, pencils, and people who are motivated and care. These people are probably already being paid by you to do most of this work. Our experience is that if these people are treated with respect and given some simple tools they will do amazing things beyond what you thought was possible. This is a low tech humanistic approach that has a fabulous rate of return. It's also something that can be immediately implemented

The Mechanism of Stress-Relief Cracking in a Ferritic Alloy Steel

A novel stress-relaxation technique and extensive microstructural characterization of the carbide precipitation, elemental segregation, and fracture modes were used to investigate stress-relief cracking in a ferritic alloy steel ABSTRACT. Stress-relief cracking is a major cause of weld failures in creepresistant, precipitation-strengthened materials such as ferritic alloy steels, stainless steels, and Ni-based superalloys. Stressrelief cracking occurs primarily in the coarse-grained heat-affected zone of weldments. Although the general causes of stress-relief cracking are known, the underlying mechanisms are very much a topic of debate. The mechanism of stressrelief cracking in the coarse-grained heataffected zone (CGHAZ) of a new ferritic alloy steel (HCM2S) was investigated through stress-relaxation testing and detailed microstructural characterization. The CGHAZ simulation and stress-relaxation testing was performed using Gleeble techniques. The time to failure exhibited C-curve behavior as a function of temperature. A balance of intergranular and intragranular carbide precipitation controlled the stress-relief cracking susceptibility. Cracking initiated at prior austenite grain boundaries by cavity nucleation on incoherent, Fe-rich M3C carbides. The grain interiors were resistant to plastic deformation due to precipitation strengthening by small (5-40 nm) alloy carbides. Elemental segregation played no detectable role in the stress-relief cracking failures. Much of the microstructural characterization was performed using a VG603 FEG STEM having a probe size of about 1.5 nm. The small probe size allowed nano-sized precipitates to be individually analyzed by using EDS and elemental EDS traces taken across prior austenite grain boundaries. In addition, SE STEM imaging with the VG603 FEG STEM was able to resolve small precipitates that were previously unobservable using conventional TEM and STEM techniques. The results of this study form a basis for heat treatment and welding process variables for HCM2S to avoid stress-relief cracking. In addition, these procedures and analytical results can be applied to other materials to avoid microstructures that are susceptible to stress-relief cracking