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Full-Text Articles in Physical Sciences and Mathematics

Cover Crop Biomass Production And Water Use In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Johnathon D. Holman Aug 2015

Cover Crop Biomass Production And Water Use In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Johnathon D. Holman

David C. Nielsen

The water-limited environment of the semiarid Central Great Plains may not produce enough cover crop biomass to generate benefits associated with cover crop use in more humid regions. There have been reports that cover crops grown in mixtures produce more biomass with greater water use efficiency than single-species plantings. This study was conducted to determine differences in cover crop biomass production, water use efficiency, and residue cover between a mixture and single-species plantings. The study was conducted at Akron, CO, and Sidney, NE, during the 2012 and 2013 growing seasons under both rainfed and irrigated conditions. Water use, biomass, and …


Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile Apr 2013

Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile

Ahmed Harb Rabia A.H. Rabia

Aerial photography is an important source of high resolution remotely sensed data. Before 1970, aerial photographs were the only remote sensing data source for land use and land cover classification. Using these old aerial photographs improve the final output of land use and land cover change detection. However, classic techniques of aerial photographs classification like manual interpretation or screen digitization require great experience, long processing time and vast effort. A new technique needs to be developed in order to reduce processing time and effort and to give better results. Geographic object based image analysis (GEOBIA) is a newly developed area …


Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro Mar 2013

Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro

Ahmed Harb Rabia A.H. Rabia

Land suitability assessment for irrigation is a very important tool not only in terms of agriculture development planning, but also to overcome the global problem of water scarcity. The aim of this study is to spatially evaluate land suitability of the study area, Kilte Awulaelo district in Ethiopia, for surface and drip irrigation methods based on GIS and remote sensing approaches. This work has been done as a part of the 29th Course Professional Master in Istituto Agronomico per l’Oltremare, Florence, Italy. Final suitability maps show the irregularity of suitability classes’ distribution over the study area. Results show that only …


Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia Mar 2013

Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia

Ahmed Harb Rabia A.H. Rabia

In an ecosystem, there is need to establish the quantity and quality of resources and their suitability for a certain range of land uses in order to assure its future productivity and sustainability of biodiversity. Parametric methods are widely used for land suitability evaluation. A new parametric concept “equation” of land suitability evaluation has been proposed to improve results of land suitability evaluation. Land suitability assessment for wheat production was conducted in order to compare results of the suggest method with classical parametric methods. Organic matter, CaCO3, pH, Slope, texture, drainage, depth, EC and altitude were recognized as factors affecting …


Travelling In Cuba, Fathi Habashi Feb 2013

Travelling In Cuba, Fathi Habashi

Fathi Habashi

Contact with Cuban scientists was established in 1986 when two researchers from Centro de Investigaciones para Industria Minero Metalurgica in Havana visited Laval University to get acquainted with research activities in the area of extractive metallurgy. This was followed in early 1987 by two more researchers from the same centre. Invitations were then received in late 1987, 1989, and 2008 to visit the nickel refineries in Cuba and to hold seminars at the University of Havana. The present report outlines these activities.


Do We Really Need New Policies? A Study On Soil Sealing In Egypt, Ahmed Harb Rabia Oct 2012

Do We Really Need New Policies? A Study On Soil Sealing In Egypt, Ahmed Harb Rabia

Ahmed Harb Rabia A.H. Rabia

Egypt has the lowest area of agricultural land per individual in Africa. The agricultural land stands for a total of approximately 3.5 million ha which characterized about 3.5% of the total area of Egypt in 2007. The urban encroachment over arable productive agricultural land in Egypt is common and is called (urban desertification). Therefore, the annual loss of arable land to urbanization is 1.2%. This indicates a serious situation to the agricultural area. the Academy of Scientific Research & Technology (1994) has reported that during the period from 1978 to 1984, the annual expansion rates of the dwelling area ranged …


Mapping Soil Erosion Risk Using Rusle, Gis And Remote Sensing Techniques, Ahmed Harb Rabia A.H. Rabia Jul 2012

Mapping Soil Erosion Risk Using Rusle, Gis And Remote Sensing Techniques, Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Soil erosion is one of the major causes of land degradation in arid and semi-arid areas like Ethiopia, including Tigray Highlands, which is highly affected by the risk of desertification. Tackling on-site effects of soil erosion requires understanding of the rates of soil loss as well as identification of the major controlling factors that accelerate or slow down these processes. The study aims to quantify the soil loss by erosion process and to specify the main factor affecting the Erosion development in the study area. The Study area was Kilte Awulaelo District which is situated in the eastern part of …


Modeling Of Soil Sealing By Urban Sprawl In Wukro, Ethiopia Using Remote Sensing And Gis Techniques, Ahmed Harb Rabia A.H. Rabia May 2012

Modeling Of Soil Sealing By Urban Sprawl In Wukro, Ethiopia Using Remote Sensing And Gis Techniques, Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Soil sealing is the covering of the soil surface with materials like concrete and stone, as a result of new buildings, roads, parking places but also other public and private space. Soil sealing by urban sprawl continues to increase all over the world where the area of urbanized land is increasing even more rapidly than the population. The degree of sealing is associated to the land use type and the density of population. Techniques of Remote Sensing and Geographical Information System (GIS) have been used widely to measure urban sprawl and to analyze the spatial features and unique mechanism of …


Gis Spatial Modeling For Land Degradation Assessment In Tigray, Ethiopia., Ahmed Harb Rabia A.H. Rabia May 2012

Gis Spatial Modeling For Land Degradation Assessment In Tigray, Ethiopia., Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Land degradation can be described as reduction in the present and prospective land quality and production, due to natural or anthropogenic dynamics. This phenomenon is one of the most important problems facing farmers and decision makers in several countries. This study aims to use GIS spatial modeling to quantify land (physically and chemically) degradation in the study area based on remotely sensed and field survey’s data. A GIS spatial model has been developed based on the LADA- FAO methodology to apply a land degradation assessment in the study area. Final land degradation map has been produced by combining the outputs …


Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi Jan 2012

Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi

Fathi Habashi

The Book covers the history of pyrite - - how it was a strategic mineral necessary for the production of elemental sulfur needed for making gunpowder for military purposes and for the production of SO2 needed for making sulfuric acid for the chemical industry. Now its presence is a nuisance in tailings ponds. The book also covers the processing of pyrite containing gold, its chemistry and technology, the processing of pyrite cinder for the production of a variety of metals, and its behaviour towards autotrophic microorganisms.


Metalurgia Extractiva Y Política Nacional, Fathi Habashi Jan 2011

Metalurgia Extractiva Y Política Nacional, Fathi Habashi

Fathi Habashi

Should a country export its mineral wealth in form of concentrates or should it locally treat its ores to produce metals as final products? In the past centuries pyrometallurgy was the only route to extract metals from ores and this required a large capital investment many countries could not afford to raise. This situation encouraged marketing of concentrates. Today, metallurgists have the option to use the hydrometallurgical route to process ores and concentrates at a reasonable capital investment. This opened the way to the possibility of processing ores locally. When need arises to increase production new units can be added …


Leaching Mechanism Of Semiconducting Minerals, Fathi Habashi Dec 2010

Leaching Mechanism Of Semiconducting Minerals, Fathi Habashi

Fathi Habashi

The mechanism of leaching of semiconducting minerals such as PbS, ZnS, UO2, etc., has been the subject of intensive speculation by hydrometallurgists in the early 1950s. The electrochemical mechanism proposed in 1970 by the author in volume 2 of his Principles of Extractive Metallurgy avoids the assumption of forming intermediate complexes that cannot be isolated or identified.


Background Fluorescence In Groundwater From A Tropical Karst Island Aquifer, Michelle Hoffman Sep 2010

Background Fluorescence In Groundwater From A Tropical Karst Island Aquifer, Michelle Hoffman

Michelle Hoffman

Background levels of four fluorescent compounds were monitored biweekly at thirteen sampling sites on Guam, consisting of subtidal and intertidal springs, dissolution fractures, and internal upland contact spring discharge, over a 13-month period from 2006 to 2007. Samples were compared to local precipitation and to seawater samples from four nearby reef flats. The data revealed that the concentrations of optical brighteners were consistently two orders of magnitude greater than either sodium fluorescein or rhodamine WT, while Eosine Y was rarely detected. Background levels in seawater, by comparison, accounted for 25% or more of the fluorescent compounds detected at the thirteen …


Metals: Typical And Less Typical, Transition And Inner Transition, Fathi Habashi Mar 2010

Metals: Typical And Less Typical, Transition And Inner Transition, Fathi Habashi

Fathi Habashi

While most chemists agree on what is a metal and what is a non-metal there is a disagreement with respect to what is a metalloid and what is a transition metal. It is believed that this problem can be solved if two new terms are adopted: typical and less typical metals. These new terms will also help reconcile the European Periodic Table versus the North American regarding numbering of groups as well as the IUPAC numbering which could be as well abandoned in favour of group names as will be shown in the manuscript.


Phosphate Industry And The Radon Problem, Fathi Habashi Feb 2010

Phosphate Industry And The Radon Problem, Fathi Habashi

Fathi Habashi

The problem of radon generated during the treatment of phosphate rock by sulfuric acid to produce fertilizers can be solved by using nitric acid. In this case radium, which is the source of radon, goes into solution and can be precipitated by a controlled method and safely disposed of. A variety of options are discussed. Text in Farsi with English translation.


Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi Jan 2010

Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi

Fathi Habashi

Water a component of the Four Elements considered by the ancient philosophers as essential for survival, played, and is still playing an essential role in society. Great civilizations in ancient times developed along great rivers. The ancient peoples knew how to manage water supplies by digging canals, controlling floods, and using water for irrigation. They designed equipment that used water to measure the time, to determine the density of solids, to fight fires, and to create vacuum. Modern engineers exploited water flow to design and construct huge hydroelectric power stations. Waterways and navigation systems were also an essential element for …


Chemistry And Metallurgy In The Great Empires, Fathi Habashi Jan 2009

Chemistry And Metallurgy In The Great Empires, Fathi Habashi

Fathi Habashi

It is remarkable that certain countries expand to become great empires then as time goes by they gradually decline while others rise. This book attempts to briefly trace the history of chemistry and metallurgy through the different empires that became at one time great and then faded away. In 272 pages 21.5 x 28 cm, the author outlines the inter-relation of chemistry, metallurgy, mining, and medicine, the idea of the divinity of kings and the formation of nations, and finally the rise and fall of the empires. He then covers the ancient and medieval empires, followed by the empires from …


Science, Technology, And Society, Fathi Habashi Jan 2009

Science, Technology, And Society, Fathi Habashi

Fathi Habashi

Science, technology, and society is a vast and complex question. It is discussed here from five points: social responsibility of scientists, migration and movement of scholars, philanthropy and its role in education and culture, enlightened despots and their influence on science and culture, and finally the social aspects of mining. The book is meant for the general reader but can benefit scientists as well. It is fully illustrated with colored pictures. It is hoped that it will serve as an introduction to this field to the young generation and inspire them to serve society.


Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams Jan 2008

Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams

Noah D Hall

The Earth’s climate is warming. This is the unequivocal conclusion of climate scientists. Despite the complexities of climatology, certain consistent trends emerge with implications for water availability: as the world gets warmer, it will experience increased regional variability in precipitation, with more frequent heavy precipitation events and more susceptibility to drought. These simple facts will have a profound impact on freshwater resources throughout the United States, as the warmer climate will reduce available water supplies and increase water demand. Unfortunately, current water law and policy are not up to the new challenges of climate change and resulting pressures on freshwater …


Ecological And Agricultural Applications Of Synchrotron Ir Microscopy, Ted K. Raab, John P. Vogel Sep 2004

Ecological And Agricultural Applications Of Synchrotron Ir Microscopy, Ted K. Raab, John P. Vogel

Ted K. Raab

The diffraction-limited spot size of synchrotron-based IR microscopes provides cell-specific, spectrochemical imaging of cleared leaf, stem and root tissues of the model genetic organism Arabidopsis thaliana, and mutant plants created either by T-DNA insertional inactivation or chemical mutagenesis. Spectra in the wavelength region from 6 to 12 microns provide chemical and physical information on the cell wall polysaccharides of mutants lacking particular biosynthetic enzymes (‘‘Cellulose synthase-like’’ genes). In parallel experiments, synchrotron IR microscopy delineates the role of Arabidopsis cell wall enzymes as susceptibility factors to the fungus Erysiphe cichoracearum, a causative agent of powdery mildew disease. Three genes, pmr4, pmr5, …


Quelques Conseils À Nos Nouveau Diplomés, Fathi Habashi Jun 2003

Quelques Conseils À Nos Nouveau Diplomés, Fathi Habashi

Fathi Habashi

An advice, the old wise man Polonius offered to the young Hamlet was “Neither a borrower, nor a lender be”, may be no longer pertinent. Some more relevant advices are offered to new graduates of the twentieth century. Available in English, French, and Spanish


From Alchemy To Atomic Bombs. Book Review By George Kauffman, Fathi Habashi Jan 2003

From Alchemy To Atomic Bombs. Book Review By George Kauffman, Fathi Habashi

Fathi Habashi

Review of the book "From Alchemy to Atomic Bombs" by Fathi Habashi published by Métallurgie Extractive Québec. The review is written by Professor George Kauffman at California State University, Fresno.


Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville Sep 2002

Pmr6, A Pectate Lyase–Like Gene Required For Powdery Mildew Susceptibility In Arabidopsis, John P. Vogel, Ted K. Raab, Celine Schiff, Shauna C. Somerville

Ted K. Raab

The plant genes required for the growth and reproduction of plant pathogens are largely unknown. In an effort to identify these genes, we isolated Arabidopsis mutants that do not support the normal growth of the powdery mildew pathogen Erysiphe cichoracearum. Here, we report on the cloning and characterization of one of these genes, PMR6. PMR6 encodes a pectate lyase-like protein with a novel C-terminal domain. Consistent with its predicted gene function, mutations in PMR6 alter the composition of the plant cell wall, as shown by Fourier transform infrared spectroscopy. pmr6-mediated resistance requires neither salicylic acid nor the ability to perceive …


Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin May 2001

Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin

Ted K. Raab

A bright synchrotron light source operated by the Lawrence Berkeley National Laboratory served as an external source for infrared (IR) microscopy of plant root microcosms. Mid-IR light from synchrotrons is 2-3 orders of magnitude brighter than conventional sources, providing contrast based on the chemical information in the reflected signal at a spatial resolution near the diffraction-limit of 3-10 microns. In an experiment using plant root microcosms fitted with zinc selenide IR-transmissive windows (50 mm x 20 mm x 1 mm), we describe chemical differences and similarities within the root zone of mung bean (Vigna radiata L.), grown with or without …


Toward An Ecosystem Approach To Remediation In The Great Basin, Ted K. Raab Jan 2000

Toward An Ecosystem Approach To Remediation In The Great Basin, Ted K. Raab

Ted K. Raab

We consider the web of interactions among geologic materials, soils, plants, and animals to ask, "If mining or other extractive energy technologies occur in desert regions, what do we need to know to return the land to productivity?" The Great Basin represents a formidable challenge in this regard, as winters in these cold deserts and seasonal lack of moisture during parts of the year severely constrain the growing season for vegetation. Due to the nature of current or proposed mining activities in this region, we have chosen to concentrate on two potential pollutants: the trace element selenium (Se) and nitrate …


A Memorable Meeting, February 1994, Fathi Habashi Feb 1994

A Memorable Meeting, February 1994, Fathi Habashi

Fathi Habashi

Decision taken at the Steering Committee Meeting of the International Mineral Processing Congress in San Francisco February 1994 to name the IMPC Award.


Hidrometalurjide Yeni, Fathi Habashi Jan 1979

Hidrometalurjide Yeni, Fathi Habashi

Fathi Habashi

Turkish translation of F. Habashi, “Recent Advances in Hydrometallurgy,” Proceedings International Mineral Processing Congress, Warsaw, 1979, edited by J. Laskowski, published by Elsevier, pp. 902–935


Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi Jan 1975

Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi

Fathi Habashi

Review of the first volume of Progress in Extractive Metallurgy edited by Fathi Habashi and published by Gordon & Breach in New York in 1975. The review was written by Professor Dobrokhotov at the Leningrad Mining Institute.