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Articles 6811 - 6840 of 6924
Full-Text Articles in Physical Sciences and Mathematics
Candoluminescence Of Cave Gypsum, John R. Sweet, John W. Hess, William B. White
Candoluminescence Of Cave Gypsum, John R. Sweet, John W. Hess, William B. White
International Journal of Speleology
A selection of gypsum specimens from a variety of caves as well as CaSO4 synthesized in the laboratory emit both a green and yellow candoluminescence when excited by a hydrogen diffusion flame. The green emission is attributed to dehydration of gypsum to bassanite and the yellow emission appears upon further dehydration to anhydrite. The source of the luminescence is ascribed to minor concentrations of Mn2+ in the gypsum.
Teaching Resources In Speleology And Karst: A Valuable Educational Tool, Jo De Waele
Teaching Resources In Speleology And Karst: A Valuable Educational Tool, Jo De Waele
International Journal of Speleology
There is a growing need in the speleological community of tools that make teaching of speleology and karst much easier. Despite the existence of a wide range of major academic textbooks, often the caver community has a difficult access to such material. Therefore, to fill this gap, the Italian Speleological Society, under the umbrella of the Union International de Spéléologie, has prepared a set of lectures, in a presentation format, on several topics including geology, physics, chemistry, hydrogeology, mineralogy, palaeontology, biology, microbiology, history, archaeology, artificial caves, documentation, etc. These lectures constitute the “Teaching Resources in Speleology and Karst”, available online. …
Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen
Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen
International Journal of Speleology
The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum speleothems …
Palaeomagnetic Research On Karst Sediments In Slovenia, Nadja Zupan Hajna, Andrej Mihevc, Petr Pruner, Pavel Bosàk
Palaeomagnetic Research On Karst Sediments In Slovenia, Nadja Zupan Hajna, Andrej Mihevc, Petr Pruner, Pavel Bosàk
International Journal of Speleology
We have conducted palaeomagnetic and magnetostratigraphic research on karst sediments in Slovenia since 1997. More than 2,000 samples were taken and analysed in 36 different profiles at 21 locations in caves and on the surface. Standard palaeomagnetic analyses were used (thermal and alternating field demagnetisation, magnetic susceptibility measurements, etc.). There is no evidence of younger marine deposition than Eocene in the SW part of Slovenia. Younger sediments occur only in caves and very rarely on the karst surface (different soils and a few remains of terrigeneous sediments). Marine and terrestrial Tertiary to Plio–Quaternary deposition occurs in the SE and E …
Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet
Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet
International Journal of Speleology
The Choranche Cave system (Vercors, France) is an excellent locality for measuring the growth rates of large numbers soda straws. This is especially the case for the Coufin Cave, as enlargement of the cave entrance in 1875 led to a change in stalactite color from brown to white, thus providing a reliable chronomarker. The date of this brown-to-white calcite transition has been confirmed by lamina counting. We measured and georeferenced the growth-lengths of 306 soda straws in a 1m2 area of the roof of the Coufin Cave entrance chamber. Because of the very slow and sometimes inexistent water feeding …
Do Karst Rivers “Deserve” Their Own Biotic Index? A Ten Years Study On Macrozoobenthos In Croatia, Biljana Rađa, Sanja Puljas
Do Karst Rivers “Deserve” Their Own Biotic Index? A Ten Years Study On Macrozoobenthos In Croatia, Biljana Rađa, Sanja Puljas
International Journal of Speleology
In this study we present the results of a ten year survey of the aquatic macroinvertebrate fauna along four karst rivers: Jadro, Žrnovnica, Grab and Ruda, all of them situated in the Middle Dalmatia region of Croatia, in an attempt to construct the Iliric Biotic Index, which will be more applicable for the water quality analysis than the most frequently applied biotic index in Croatia, the Italian Modification of Extended Biotic Index. The rivers geologically belong to the Dinaric karst, unique geological phenomena in Europe. Benthic macroinvertebrates were collected along each river at 15 sites by standard methods of sampling …
A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio
A Seasonal Study Of Dissolved Cobalt In The Ross Sea, Antarctica: Micronutrient Behavior, Absence Of Scavenging, And Relationships With Zd, Cd, And P., M. A. Saito, T. J. Goepfert, A. E. Noble, E. M. Bertrand, Peter N. Sedwick, Giacomo R. Ditullio
OES Faculty Publications
We report the distribution of cobalt (Co) in the Ross Sea polynya during austral summer 2005-2006 and the following austral spring 2006. The vertical distribution of total dissolved Co (dCo) was similar to soluble reactive phosphate (PO(4)(3-)), with dCo and PO(4)(3-) showing a significant correlation throughout the water column (r(2) = 0.87, 164 samples). A strong seasonal signal for dCo was observed, with most spring samples having concentrations ranging from similar to ~ 45-85 pM, whereas summer dCo values were depleted below these levels by biological activity. Surface transect data from the summer cruise revealed concentrations at the low range …
S-Nitrosothiols: Formation, Decomposition, Reactivity And Possible Physiological Effects, Moshood Kayode Morakinyo
S-Nitrosothiols: Formation, Decomposition, Reactivity And Possible Physiological Effects, Moshood Kayode Morakinyo
Dissertations and Theses
Three biologically-active aminothiols cysteamine (CA), DL-cysteine (CYSH) and DL-homocysteine, were studied in this thesis. These aminothiols react with nitrous acid (HNO2), prepared in situ, to produce S-nitrosothiols (RSNOs): S-nitrosocyteamine (CANO), S-nitrosocysteine (CYSNO) and S-nitrosohomocysteine (HCYSNO). They also react with S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylpenicillamine (SNAP) through a transnitrosation reaction to produce their corresponding RSNOs. A detailed kinetics and mechanistic study on the formation of these RSNOs and their subsequent decomposition to release nitric oxide (NO) were studied.
For all three aminothiols the stoichiometry of their reaction with nitrous acid is strictly 1:1 with the formation of one mole …
Document Builder, Thien Tran
Document Builder, Thien Tran
Master's Projects
In this paper, we consider problems related to on-demand content publishing and maintenance. Specifically, we are concerned with the recent concept of structural Content Management Systems (CMS) and its design principles. We focus on Apache Ant, a popular document generator tool for the Java development industry. However, Ant has not been widely extended beyond its capacity to deal with computer programs, which limits its utility. We analyze the Ant build script structure, study its usage, and implement an on-demand document generator for Ant. The focus is to provide a better document build model based on Ant, which can provide document …
Metamorphic Viruses With Built-In Buffer Overflow, Ronak Shah
Metamorphic Viruses With Built-In Buffer Overflow, Ronak Shah
Master's Projects
Metamorphic computer viruses change their structure—and thereby their signature—each time they infect a system. Metamorphic viruses are potentially one of the most dangerous types of computer viruses because they are difficult to detect using signature-based methods. Most anti-virus software today is based on signature detection techniques. In this project, we create and analyze a metamorphic virus toolkit which creates viruses with a built-in buffer overflow. The buffer overflow serves to obfuscate the entry point of the actual virus, thereby making detection more challenging. We show that the resulting viruses successfully evade detection by commercial virus scanners. Several modern operating systems …
Food Phone Application, Shengyu Li
Food Phone Application, Shengyu Li
Master's Projects
This project is about implementing a food menu application for users to search and upload food information by using a mobile phone. People sometimes may just know what food they wish to eat instead of the restaurants' name. Without knowing any restaurants' names, our food application's search only requires the name of the dish (e.g., hamburger, spaghetti, etc) in order to get the list of restaurants that serve these items and their corresponding information (e.g., location, hours, phone number, item's price, etc.). An advantage of using my food application is the system not only includes Google Map, but any information …
Open Source Analysis Of Biomedical Figures, David Shao
Open Source Analysis Of Biomedical Figures, David Shao
Master's Projects
With a selection of biomedical literature available for open access, a natural pairing seems to be the use of open source software to automatically analyze content, in particular, the content of gures. Considering the large number of possible tools and approaches, we choose to focus on the recognition of printed characters. As the problem of optical character recognition (OCR) under rea- sonable conditions is considered to be solved, and as open source software is fully capable of isolating the location of characters and identifying most of them accurately, we instead use OCR as an application area for the relatively recent …
Email Data Mining: An Approach To Construct An Organization Position-Wise Structure While Performing Email Analysis, Bhargav Vadher
Email Data Mining: An Approach To Construct An Organization Position-Wise Structure While Performing Email Analysis, Bhargav Vadher
Master's Projects
In this age of social networking, it is necessary to define the relationships among the members of a social network. Various techniques are already available to define user- to-user relationships across the network. Over time, many algorithms and machine learning techniques were applied to find relationships over social networks, yet very few techniques and information are available to define a relation directly over raw email data. Few educational societies have developed a way to mine the email log files and have found the inter-relation between the users by means of clusters. Again, there is no solid technique available that can …
Parallel Programming Recipes, Thuy C. Nguyenphuc
Parallel Programming Recipes, Thuy C. Nguyenphuc
Master's Projects
Parallel programming has become vital for the success of commercial applications since Moore’s Law will now be used to double the processors (or cores) per chip every technology generation. The performance of applications depends on how software executions can be mapped on the multi-core chip, and how efficiently they run the cores. Currently, the increase of parallelism in software development is necessary, not only for taking advantage of multi-core capability, but also for adapting and surviving in the new silicon implementation. This project will provide the performance characteristics of parallelism for some common algorithms or computations using different parallel languages. …
Exhaustive Statistical Analysis For Detection Of Metamorphic Malware, Aditya Govindaraju
Exhaustive Statistical Analysis For Detection Of Metamorphic Malware, Aditya Govindaraju
Master's Projects
Malware is a serious threat to the security of the system. With the widespread use of the World Wide Web, there has been a tremendous increase in virus attacks, making computer security an essential for every personal computer. The rat-race between virus writers and detectors has led to improved viruses and detection techniques. In recent years, metamorphic malwares have posed serious challenge to anti-virus writers. Current signature based detection techniques, heuristic based techniques are not comprehensive solutions. A formidable solution to detection of metamorphic malware is void. This paper investigates the problem of malware detection, specifically metamorphic malwares. The paper …
Approximate Disassembly, Dhivyakrishnan Radhakrishnan
Approximate Disassembly, Dhivyakrishnan Radhakrishnan
Master's Projects
For the past two decades, computer viruses have been a constant security threat. A computer virus is a type of malware that may damage computer systems by destroying data, crashing the system, or through other malicious activity. Among the different types of viruses, metamorphic viruses are one of the most difficult to detect since such viruses change their internal structures with each mutation, making signature-based detection infeasible. Many construction kits are available that can be used to easily generate metamorphic strains of any given virus. Previous work has shown that metamorphic viruses are detectable using Hidden Markov Models (HMM). In …
Basic Skills Testing In Math 2008, Susie M. Lanier, Sharon Taylor, Donna B. Saye
Basic Skills Testing In Math 2008, Susie M. Lanier, Sharon Taylor, Donna B. Saye
Proceedings of the Annual Meeting of the Georgia Association of Mathematics Teacher Educators
Math 2008 is an Area F course for early childhood majors in the University System of Georgia. The course covers basic skills that pre-service teachers will most likely be teaching in their career. At Georgia Southern University, many students in the course do not possess or have forgotten these basic skills. In Fall 2009, a basic skills test was implemented for Math 2008. Students must earn a score of 90 or higher on the test in order to pass the course. The test not only serves to let students know their areas of weakness, but also informs the instructor’s teaching. …
Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova
Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova
LSU Doctoral Dissertations
This dissertation is concerned with the applications of the Riemann-Hilbert problem on a hyperelliptic Riemann surface to problems on supercavitating flows of a liquid around objects. For a two-dimensional steady irrotational flow of liquid it is possible to introduce a complex potential w(z) which allows to apply the powerful methods of complex analysis to the solution of fluid mechanics problems. In this work problems on supercavitating flows of a liquid around one or two wedges have been stated. The Tulin single-spiral-vortex model is employed as a cavity closure condition. The flow domain is transformed into an auxiliary domain with known …
Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl
Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl
LSU Doctoral Dissertations
The Earth’s geochemical evolution is recorded in the rocks that compose its lithosphere. Specifically, sulfate minerals have been identified as being repositories of information concerning the past hydrosphere, atmosphere and biosphere. This is due to the non-labile nature of SO42- and its ability to store a record of the oxidative reactions and oxygen sources involved in its formation. Microbial dissimilatory sulfate reduction (MDSR) and sulfide oxidation cause oxygen from H2O and O2 to be trapped to varying degrees in ambient, dissolved SO42-. In order to better interpret the H2O and O2 signals in SO42-, we must deepen our understanding of …
Modeling Thermal Phenomena And Searching For New Thermally Induced Monitor Signals In Large Sale Gravitational Wave Detectors, Rupal Shashikant Amin
Modeling Thermal Phenomena And Searching For New Thermally Induced Monitor Signals In Large Sale Gravitational Wave Detectors, Rupal Shashikant Amin
LSU Doctoral Dissertations
The Laser Interferometer Gravitational-wave Observatory (LIGO) array’s 4 km detectors have transitioned from an initial configuration (iLIGO) to an enhanced configuration (eLIGO) [1]. Both configurations relied on high circulating laser powers to achieve sensitivity goals between 150 Hz and 8 kHz. These power levels were sufficient to induce thermally driven focal affects in the primary optics. Since the detectors were designed to achieve maximum sensitivity when laser light was optimally coupled (mode matched) into the antenna, small deviations in focal parameters influenced performance. A laser based thermal compensation system (TCS) was installed for use in both configurations to counteract excessive …
Orthogonal Grassmannians And Hermitian K-Theory In A¹-Homotopy Theory Of Schemes, Girja Shanker Tripathi
Orthogonal Grassmannians And Hermitian K-Theory In A¹-Homotopy Theory Of Schemes, Girja Shanker Tripathi
LSU Doctoral Dissertations
In this work we prove that the hermitian K-theory is geometrically representable in the A^1 -homotopy category of smooth schemes over a field. We also study in detail a realization functor from the A^1 -homotopy category of smooth schemes over the field R of real numbers to the category of topological spaces. This functor is determined by taking the real points of a smooth R-scheme. There is another realization functor induced by taking the complex points with a similar description although we have not discussed this other functor in this dissertation. Using these realization functors we have concluded in brief …
Three-Body Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron C. Laforge
Three-Body Dynamics In Single Ionization Of Atomic Hydrogen By 75 Kev Proton Impact, Aaron C. Laforge
Doctoral Dissertations
"Doubly differential cross sections (DDCS) for single ionization of atomic hydrogen by 75 keV proton impact have been measured as a function of the projectile scattering angle and energy loss. This pure three-body collision system represents a fundamental test case for the study of the reaction dynamics in few-body systems. A comparison between theory and experiment reveals that three-body dynamics is important at all scattering angles, and that an accurate description of the role of the projectile-target nucleus interaction as well as the second order projectile-electron interaction remains a major challenge to theory. However, progress is being made in understanding …
Analysis And Occurrence Of Disinfection By-Products In Fresh And Salt Water, Honglan Shi
Analysis And Occurrence Of Disinfection By-Products In Fresh And Salt Water, Honglan Shi
Doctoral Dissertations
"Haloacetic acids, trihalomethanes, and bromate are important toxic water disinfection by-products (DBPs) that the US Environmental Protection Agency (USEPA) regulates in drinking water. Iodoacetic acids and halonitromethanes (HNMs) are the unregulated emerging DBPs that have been recently found in the disinfected drinking waters, and which have much higher toxicity than the regulated DBPs. The purpose of this study was to develop new analytical methods for analysis of these emerging DBPs, to study their occurrence in Missouri drinking water systems, and to investigate the occurrence and formation of these DBPs in saltwater and seawater based marine park aquaria. A new rapid …
Design Sensitivities Of The Superconducting Parallel-Bar Cavity, Subashini U. De Silva, Jean Delayen
Design Sensitivities Of The Superconducting Parallel-Bar Cavity, Subashini U. De Silva, Jean Delayen
Physics Faculty Publications
The superconducting parallel-bar cavity has properties that makes it attractive as a deflecting or crabbing rf structure. For example it is under consideration as an rf separator for the Jefferson Lab 12 GeV upgrade and as a crabbing structure for a possible LHC luminosity upgrade. In order to maintain the purity of the deflecting mode and avoid mixing with the near accelerating mode caused by geometrical imperfection, a minimum frequency separation is needed which depends on the expected deviations from perfect symmetry. We have done an extensive analysis of the impact of several geometrical imperfections on the properties of the …
Electromagnetic Structure And Reactions Of Few-Nucleon Systems In Χeft, L. Girlanda, S. Pastore, R. Schiavilla, M. Viviani
Electromagnetic Structure And Reactions Of Few-Nucleon Systems In Χeft, L. Girlanda, S. Pastore, R. Schiavilla, M. Viviani
Physics Faculty Publications
We summarize our recent work dealing with the construction of the nucleon-nucleon potential and associated electromagnetic currents up to one loop in chiral effective field theory (χEFT). The magnetic dipole operators derived from these currents are then used in hybrid calculations of static properties and low-energy radiative capture processes in few-body nuclei. A preliminary set of results are presented for the magnetic moments of the deuteron and trinucleons and thermal neutron captures on p, d, and ³He.
Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani
Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani
Physics Faculty Publications
We present a study of high energy photodisintegration of proton-pairs through the γ + 3He → p + p + n channel. Photon energies, Eγ , from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. The s−11 scaling of the cross section, as predicted by the constituent counting rule for two nucleon photodisintegration, was observed for the first time. The onset of the scaling is at a higher energy and the cross section is significantly lower than for deuteron (pn pair) photodisintegration. …
Excitation-Induced Germanium Quantum Dot Formation On Si (100)-(2×1), Ali Oguz Er, Hani E. Elsayed-Ali
Excitation-Induced Germanium Quantum Dot Formation On Si (100)-(2×1), Ali Oguz Er, Hani E. Elsayed-Ali
Physics Faculty Publications
The effect of nanosecond pulsed laser excitation on the self-assembly of Ge quantum dots grown by pulsed laser deposition on Si (100)-(2×1) was studied. In situ reflection high-energy electron diffraction and ex situ atomic force microscopy were used to probe the quantum dot structure and morphology. At room temperature, applying the excitation laser decreased the surface roughness of the grown Ge film. With surface electronic excitation, crystalline Ge quantum dots were formed at 250 °C, a temperature too low for their formation without excitation. At a substrate temperature of 390 °C, electronic excitation during growth was found to improve the …
Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein
Measurement Of Single- And Double-Spin Asymmetries In Deep Inelastic Pion Electroproduction With A Longitudinally Polarized Target, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, G. Dodge, G. Gavalian, N. Guler, A. Klein, S E. Kuhn, D. Martinez, M. R. Niroula, F. Sabatié, H. Seraydaryan, S. Tkachenko, L. B. Weinstein
Physics Faculty Publications
We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations …
Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku
Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku
Physics Faculty Publications
We present measurements of the charge balance function, from the charged particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au collisions at √sNN = 200 GeV using the STAR detector at RHIC. We observe that the balance function is boost-invariant within the pseudorapidity coverage [ − 1.3 , 1.3 ] . The balance function properly scaled by the width of the observed pseudorapidity window does not depend on the position or size of the pseudorapidity window. This scaling property also holds for particles in different transverse momentum ranges. In addition, we find that the width …
Plasma Treatment Of Bulk Niobium Surface For Superconducting Rf Cavities: Optimization Of The Experimental Conditions On Flat Samples, M. Rašković, J. Upadhyay, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips
Plasma Treatment Of Bulk Niobium Surface For Superconducting Rf Cavities: Optimization Of The Experimental Conditions On Flat Samples, M. Rašković, J. Upadhyay, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips
Physics Faculty Publications
Accelerator performance, in particular the average accelerating field and the cavity quality factor, depends on the physical and chemical characteristics of the superconducting radio-frequency (SRF) cavity surface. Plasma based surface modification provides an excellent opportunity to eliminate nonsuperconductive pollutants in the penetration depth region and to remove the mechanically damaged surface layer, which improves the surface roughness. Here we show that the plasma treatment of bulk niobium (Nb) presents an alternative surface preparation method to the commonly used buffered chemical polishing and electropolishing methods. We have optimized the experimental conditions in the microwave glow discharge system and their influence on …