Application of Multispectral Reflectance Studies of Soils: Pre-Landsat

It was recognized in the 1960\u27s that measuring the spectral, spatial and temporal variation of electromagnetic fields reflected and emitted from the Earth\u27s surface had many potential applications in the field of agriculture. As a result, computer-implemented pattern recognition techniques were used to analyze multispectral data for the purpose of delineating soil differences. Spectral data were obtained (1) in the laboratory by scanning soil samples with a double-beam spectrophotometer (Beckman DK-2A) and (2) in the field by scanning large areas of soils with an airborne multispectral scanner. The results obtained through this early research clearly illustrated relationships between the reflected and emitted energy from soils and other physical and chemical properties of those soils. The possibility of sampling large geographic areas and obtaining information about various soil parameters within a relatively short time period appeared to be of great value to potential users, i.e. soil surveyors, soil conservationists and other resource management personnel

Mechanical properties and fracture patterns of graphene (graphitic) nanowiggles

publisher: Elsevier articletitle: Mechanical properties and fracture patterns of graphene (graphitic) nanowiggles journaltitle: Carbon articlelink: http://dx.doi.org/10.1016/j.carbon.2017.04.018 content_type: article copyright: © 2017 Elsevier Ltd. All rights reserved.publisher: Elsevier articletitle: Mechanical properties and fracture patterns of graphene (graphitic) nanowiggles journaltitle: Carbon articlelink: http://dx.doi.org/10.1016/j.carbon.2017.04.018 content_type: article copyright: © 2017 Elsevier Ltd. All rights reserved.This work was supported in part by the Brazilian Agencies CNPq, CAPES and FAPESP. The authors would like to thank the Center for Computational Engineering and Sciences at Unicamp for financial support through the FAPESP/CEPID Grant 2013/08293-7. N.M.P. is supported by the European Research Council PoC 2015 “Silkene” No. 693670, by the European Commission H2020 under the Graphene Flagship Core 1 No. 696656 (WP14 “Polymer Nanocomposites”) and under the Fet Proactive “Neurofibres” No. 732344

Interfacial Chemistry in Al/CuO Reactive Nanomaterial and Its Role in Exothermic Reaction.

Interface layers between reactive and energetic materials in nanolaminates or nanoenergetic materials are believed to play a crucial role in the properties of nanoenergetic systems. Typically, in the case of Metastable Interstitial Composite nanolaminates, the interface layer between the metal and oxide controls the onset reaction temperature, reaction kinetics, and stability at low temperature. So far, the formation of these interfacial layers is not well understood for lack of in situ characterization, leading to a poor control of important properties. We have combined in situ infrared spectroscopy and ex situ X-ray photoelectron spectroscopy, differential scanning calorimetry, and high resolution transmission electron microscopy, in conjunction with firstprinciples calculations to identify the stable configurations that can occur at the interface and determine the kinetic barriers for their formation. We find that (i) an interface layer formed during physical deposition of aluminum is composed of a mixture of Cu, O, and Al through Al penetration into CuO and constitutes a poor diffusion barrier (i.e., with spurious exothermic reactions at lower temperature), and in contrast, (ii) atomic layer deposition (ALD) of alumina layers using trimethylaluminum (TMA)produces a conformal coating that effectively prevents Al diffusion even for ultrathin layer thicknesses (∼0.5 nm), resulting in better stability at low temperature and reduced reactivity. Importantly, the initial reaction of TMA with CuO leads to the extraction of oxygen from CuO to form an amorphous interfacial layer that is an important component for superior protection properties of the interface and is responsible for the high system stability. Thus, while Al e-beam evaporation and ALD growth of an alumina layer on CuO both lead to CuO reduction, the mechanism for oxygen removal is different, directly affecting the resistance to Al diffusion. This work reveals that it is the nature of the monolayer interface between CuO and alumina/Al rather than the thickness of the alumina layer that controls the kinetics of Al diffusion, underscoring the importance of the chemical bonding at the interface in these energetic materials

Geologic Interpretation of Remote Sensor Data for the Big Desert Area of Idaho

Investigated area covers basalt lava flows in the Big Desert Area and surroundings, Landsat data collected August 23, 1978, covering the area roughly from 112°45\u27 to 114°00\u27 west and 43°00\u27 to 43°45\u27 north was used for the analysis. To facilitate computer analysis procedures, the area was divided into two equal parts: eastern and western, A systematic procedure was used to sample and cluster data representing 2% of the area. The resulting cluster classes were merged until the divergences between classes were generally greater than 1500. This resulted in 22 and 19 separable spectral classes for the eastern and western parts, respectively. The final classification was made using a minimum distance to the mean classification algorithm. Visual analyses utilizing aerial photography of the area were performed to characterize different lava types and to compare with the computer classification results of the Landsat data. In addition, structural analyses and interpretation of fissures within the lava flows and fractures of the surrounding area were performed in order to develop a geological model of the structural control of the lava flows of the Big Desert Area

Mapping and Estimating Areal Extent of Severely Eroded Soils of Selected Sites in Northern Indiana

The importance of soil conservation and the devastating effects of soil erosion have been noted throughout recorded human history. In the United States it has been estimated that up to two-thirds of the nation\u27s cropland is losing soil at rates up to 5 tons/A (11 mt/ha) while nearly 15% is losing more than 10 ton/A (22 mt/ha) per year. The Soil Conservation Service of the USDA and the Environmental Protection Agency are actively engaged in programs to reduce soil loss and subsequent stream pollution. Rapid methods of pinpointing areas undergoing accelerated erosion are needed to assist in these efforts. The use of remote sensing techniques such as conventional black and white photography has been utilized in soil survey for many years. In recent years Landsat (formerly ERTS) satellite data have been used in soil mapping for both large scale and more detailed mapping. Digital analysis techniques developed at LARS have been used to produce spectral maps with a scale as large as 1:15840 which are used to assist in mapping soils in the field. The objective of this study was to produce a ground cover classification map using computer-implemented analysis of Landsat multispectral scanner data and to evaluate the usefulness of this map in delineating severely eroded soil areas under cultivated conditions

Use of Landsat Digital Data to Assist in Mapping Soils on Arizona Rangelands

The outline and results of more than three years of field and laboratory studies are presented. The work was done in cooperation with the Soil Conservation Service, the Bureau of Land Management, and the Forest Service. Spectral maps generated from Landsat satellite data were used to aid in soil and vegetation surveys of five sites in southeastern Arizona. The sites are rangeland with varied physiography and relief, but generally sparse vegetation. It was found that spectral maps show a very positive correlation with grey tones or color patterns on photographs, and can be an excellent auxiliary tool for locating boundaries of mapping units. They can also aid in the location of representative sites for pedon descriptions, and could be used as an aid to quality control and map correlation studies in the field. The type and/or color of the geologic parent material was the dominant factor affecting the response recorded by the satellite

Landsat MSS Data as an Aid to Soil Survey - An Operational Concept

With the urgency throughout the country to complete the modern soil survey at the earliest possible date, new techniques and tools are being devised to carry out the soils mapping program. One such new mapping tool is a series of maps, derived from Landsat data, showing the spectral characteristics of soils. Whereas Jennings County, Indiana was the first county in the nation to be mapped using aerial photographs as base maps, Jasper County, Indiana is the first county to be mapped using spectral maps as an aid in. the county soil survey program. These spectral maps depict the pattern and boundaries of the soils occurring throughout the landscape of Jasper County. The spectral information was produced using computer-aided analysis (LARSYS) of Landsat-1 multispectral scanner (MSS) data collected on 9 June 1973. Prior to analysis, the Landsat data were geometrically corrected and registered to aerial photography (1:15,840) collected for the USDA/Soil Conservation Service on 3 May 1976. Soil parent material boundaries visually interpreted from the Landsat imagery were used to stratify the county and classify spectral responses representing various soils within unique parent material areas. Correlation of the spectral responses with soil characteristics was accomplished by comparing the spectral maps with conventionally prepared soil maps for randomly selected quarter sections throughout the county. Correlation of the spectral responses with soil characteristics such as surface color, surface texture, organic matter content and soil drainage was possible. The final spectral maps were correlated only with soil drainage characteristics since this correlation proved to be most consistent. The mapping of Jasper County is being carried out on half tone positive mylar which show the aerial photographic image of the mapping area. These mylar images can be overlaid on the spectral maps, thus allowing the soil scientist the benefit of both conventional aerial photography and the soil spectral characteristics for use as guides in delineating map unit boundaries. The use of the soil spectral characteristics should greatly enhance the efficiency of producing a higher quality soil survey

Extension of Laboratory-Measured Soil Spectra to Field Conditions

Spectral responses of two glaciated soils, Chalmers silty clay loam and Fincastle silt loam, formed under prairie grass and forest vegetation, respectively, were measured both in the laboratory under controlled moisture equilibria, and in the field under various moisture and crop residue conditions. An Exotech Model 20C spectroradiometer was used to obtain spectral data in the laboratory under artificial illumination. Reflectance measurements ranged from 0.52-to 2.32-µm in 0.01 µm increments. Asbestos tension tables were used to maintain a 0.10-bar moisture equilibrium following saturation of crushed, sieved soil samples. The same spectroradiometer was used outdoors under solar illumination to obtain spectral response from dry and moistened field plots with and without corn residue cover, representing the two different soils. Results indicate that laboratory-measured spectra of moist soil are directly proportional to the spectral response of that same field-measured moist bare soil over the 0.52- to 1.75-µm wavelength range. The magnitudes of difference in spectral response between identically treated Chalmers and Fincastle soils are greatest in the 0.64-to 0.8-µm transition region between the visible and near infrared, regardless of field condition or laboratory preparation studied

Evaluation of Change Detection Techniques for Monitoring Coastal Zone Environments

Development of satisfactory techniques for detecting change in coastal zone environments is required before operational monitoring procedures can be established. In an effort to meet this need a study was directed toward developing and evaluating different types of change detection techniques, based upon computer-aided analysis of Landsat multispectral scanner (MSS) data, to monitor these environments. Four change detection techniques were designed and implemented for evaluation: a) post classification comparison change detection, b) delta data change detection, c) spectrali/temporal change classification, and d) layered spectral/temporal change classification. The post classification comparison technique reliably identified areas of change and was used as the standard for qualitatively evaluating the other three techniques. The layered spectral/temporal change classification and the delta data change detection results generally agreed with the post classification comparison technique results; however, many small areas of change were not identified. Major discrepancies existed between the post classification comparison and spectral/temporal change detection results

Fine Structure in the Spectral Reflectance of Vegetation and Soils

The spectral reflective response of plants, soils, and rocks may contain information concentrated in relatively narrow spectral regions defined by the light absorption properties of the constituent atoms and molecules. The hope exists that such information will be of value in remote sensing in discriminating information classes, in identifying growth stages and stress conditions in crops, and in delineating the chemical and physical properties of soils and rocks. Satellite sensors measuring spectral regions possibly as narrow as 0.02 µm, a spectral resolution significantly better than that (0.1 µm) of the Landsat multispectral scanner, appear feasible. Fine structure in crop spectra has been reported by Collins who identified a shift in the radiance of wheat measured in the far red (near-infrared 0.73 µm) wavelengths, a shift that occurs at the onset of heading. Wiersma grouped spectra from bare soil and vegetation and found a significant amount of non-redundant information in the near-infrared wavelength region in bands 0.02 µm apart. The paper addresses the key issue raised by Wiersma; if there is information in narrow wavelength bands in reflectance spectra of bare soil and vegetation, is that information attributable to properties of the soil, the vegetation, or both. Four hundred eighty-one spectra representing soils from throughout the United States were analyzed. More than 1000 wheat spectra from four fields measured at four growth stages, several view directions, and several illumination angles were analyzed. The analyses involved the correlation coefficient computed for the spectral reflectance of adjacent wavelengths 0.02 µm apart. The analysis results show clearly the large water absorption bands at 1.4 and 1.9 µm, prominent in soil and vegetation spectra, The iron oxide absorption band at 0.9 µm is quite pronounced in the analysis results of the soils data. The vegetation analysis results show clearly the transition wavelength region between the visible and the near-infrared, anomalies at 0.53 and 0.57 µm, and minor water absorption bands at 0.95 and 1.15 µm. At three wavelengths, 0.85, 1.05, and 1.25 µm, small anomalies in the results may indicate fine structure in the reflectance data but the finding is tenuous at best