Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Chemistry

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 29821 - 29850 of 34576

Full-Text Articles in Physical Sciences and Mathematics

Study On Polarographic And Voltammetric Behaviour Of Cu(Ⅱ) Xanthosine Complex, Huizhi Fan, Jinlong Liu, Jinghao Pan May 1997

Study On Polarographic And Voltammetric Behaviour Of Cu(Ⅱ) Xanthosine Complex, Huizhi Fan, Jinlong Liu, Jinghao Pan

Journal of Electrochemistry

The polarographic and voltammetric behaviour of Cu(Ⅱ) xanthosine complex has been studied. A new sharp reduction peak is yielded at the potential of -0.14 V(vs, Ag/AgCl). The conc. of Cu(Ⅱ) is proportional to peak current of NPP in the range of 1×10 -6 ～1×10 -4 mol/L when the conc. of xanthosine is 1×10 -4 mol/L. It is indicated that the current has adsorption character. The mechanism of the electrode reaction was deduced and the ratio of the complex is Cu(Ⅱ) ∶ xanthosine=1∶1.

Go to article

Studies Of Electrocatalytic Properties Of Electrode Of Dispersed Pt On Gc Support In Ethylene Glycol Oxidation, Shengpei Chen, Shigang Lu Guoqiang Sun, Zhiyou Zhou, Shuanjing Hong May 1997

Studies Of Electrocatalytic Properties Of Electrode Of Dispersed Pt On Gc Support In Ethylene Glycol Oxidation, Shengpei Chen, Shigang Lu Guoqiang Sun, Zhiyou Zhou, Shuanjing Hong

Journal of Electrochemistry

The structures and properties of electrocatalyst of dispersed Plutinum(Pt) on glassy carbon(GC) support under different conditions were studied using cyclic voltammetry,potential step technique,x ray diffraction(XRD) and scanning Electron microscopy(SEM). The results indicated that after having been treated in high temperature,the dispersed Pt on GC support was recrystallised with preferented orientation,and the grain of Pt microcrystal become large and regular.It was illustrated that the dispersed Pt on GC support after high temperature treatment exhibited better stability and high activity for ethylene glycol oxidation.

Go to article

Study Of Electrodepositing Bright Tin Cobalt Zinc Alloy From Weak Acid Solution, Zhengzhong Zuo, Runxiang Hou, Shaochun Xia May 1997

Study Of Electrodepositing Bright Tin Cobalt Zinc Alloy From Weak Acid Solution, Zhengzhong Zuo, Runxiang Hou, Shaochun Xia

Journal of Electrochemistry

A new process of electrodeposting bright Tin Cobalt Zinc alloy from weak acid solution is proposed in this paper. The solution compositions and operating conditions are Na 3C 6H 5O 7·2H 2O 100～150,Na 2EDTA·2H 2O 20～30,SnCl 2·2H 2O 15～20,CoSO 4·7H 2O 25～35,ZnCl 2 15～20 g·L -1 ;stabilizer WDZ 1 60～100, brightener WDZ 2 15～20 mL·L -1 ; pH=4～6, D K = 0.5～5.0 A·dm -2 , T= 5～35 ℃. A bright Sn Co Zn deposit having Co about 0.5～3.5% and Zn about 1～10% is produced. The effects of bath compositions on Co or Zn content in deposit is also discussed.

Go to article

A Novel Focusing Electrophoresis Techenique Based On The Mobility Differences, Dongyung Chen, Huashui Lin, Yongliang Zhou, Bingwei Mao, Zhaoxiong Xie, Xiangdong Zhuo, Zhaowu Tian May 1997

A Novel Focusing Electrophoresis Techenique Based On The Mobility Differences, Dongyung Chen, Huashui Lin, Yongliang Zhou, Bingwei Mao, Zhaoxiong Xie, Xiangdong Zhuo, Zhaowu Tian

Journal of Electrochemistry

In this report, we present a novel analytical focusing electrophoresis technique. The principle of the technique is based on the mobility differences and has been proved successfully in our laboratory. The technique is of the same applicability as that of CZE, not limited to the protein like big molecules, with greatly improved efficiency of separation and enrichment. Advantages of this novel technique are:1. Since large volume of dilute sample solution can be injected and very narrow and concentrated zones can be obtained, extremely dilute sample can be analyzed by this novel technique in comparison with CZE. 2. Instead of with …

Go to article

Effects Of Curvature On The Electrochemical Behaviors Of Tubular Electrode, Yirong Wu, Zhenghao Wang May 1997

Effects Of Curvature On The Electrochemical Behaviors Of Tubular Electrode, Yirong Wu, Zhenghao Wang

Journal of Electrochemistry

The convective diffusion equation of tubular electrode was solved with the implicit finite difference numerical method. Comparing with the electrochemical behaviors of channel electrode, the behaviors of tubular electrode were analysised. The effects of curvature on the electrochemical behaviors of tubular electrode and the limit of applying Levich approximation to tubular electrode were discussed.

Go to article

Electrodeposition Of Amorphous Fe Cr Alloy Coating, Danhong Cheng, Weiyi Xu, Yiqin Qin, Liqun Hua, Zhongyan Zhang May 1997

Electrodeposition Of Amorphous Fe Cr Alloy Coating, Danhong Cheng, Weiyi Xu, Yiqin Qin, Liqun Hua, Zhongyan Zhang

Journal of Electrochemistry

The amorphous Fe Cr alloy coatings were obtained by controlling the composition of bath operation conditions. It was found that the pH value, the current density and the content of chromium in Fe Cr alloy coatings effect the amorphous structure of the coatings. The result of anodic polarization shows that the corrosion resistance of the amorphous coatings in acidic media is higher than the corrosion resistance of the crystal ones.

Go to article

Electrochemical Behavior Of Superoxide Dismutase On Gold Minigrid With Thin Layer Cell, Xiaqin Wu, Qian Liu, Bin Xu, Xiaoyun Men, Zongrang Zhang May 1997

Electrochemical Behavior Of Superoxide Dismutase On Gold Minigrid With Thin Layer Cell, Xiaqin Wu, Qian Liu, Bin Xu, Xiaoyun Men, Zongrang Zhang

Journal of Electrochemistry

The electrochemical behavior of superoxide dismutase (Cu, Zn SOD) was investigated on gold wire electrode and gold minigrid with thin layer cell by cyclic voltammetry. A quasi reversible redox wave of SOD has obtained on gold minigrid thin layer electrode, but only oxidation peak has observed on gold wire electrode. The electrochemical reaction parameters, such as the formal potential E 0 ′, diffusion coefficient D and standard rate constant k 0′ were estimated.

Go to article

Surface Modification Of Molten Carbonate Fuel Cell Anode, Baizeng Fang, Xinyu Liu, Xindong Wang, Shuzhen Duan May 1997

Surface Modification Of Molten Carbonate Fuel Cell Anode, Baizeng Fang, Xinyu Liu, Xindong Wang, Shuzhen Duan

Journal of Electrochemistry

In this study, the anode material of molten carbonate fuel cell was modified by the deposition of niobium on nickel surface. The results of polarization experiments reveal that the corrosion resistant properties as well as electrocatalytic activity have been improved greatly.

Go to article

An Analysis On The Microstructure Of Electrodeposited Zro 2 Ni Functionally Graded Materials, Chengjun Quan, Xinghua Xiang, Jingchuan Zhu, Zhongda Yin May 1997

An Analysis On The Microstructure Of Electrodeposited Zro 2 Ni Functionally Graded Materials, Chengjun Quan, Xinghua Xiang, Jingchuan Zhu, Zhongda Yin

Journal of Electrochemistry

The electrodeposited ZrO 2 Ni functionally graded coating was fabricated by controlling the ZrO 2 concentration in the bath, and the microstructure was analyzed by X Ray Diffraction (XRD) and Electron Probe Microanalysis (EPMA). The results show that the functionally graded coating has excellent compositional gradient distribution from the substrate to the surface. The content of ZrO 2 is up to 14.4 vol% in the surface layer and the coating consists of the t ZrO 2, m ZrO 2 and Ni phases. Owing to the ZrO 2 particles pressed by Ni atoms during electrodepositing, t→m transformation has occurred.

Go to article

Studies On Electrodeposition Of Rare Earth Metals And Their Alloys In Molten Salts, Qiqin Yand May 1997

Studies On Electrodeposition Of Rare Earth Metals And Their Alloys In Molten Salts, Qiqin Yand

Journal of Electrochemistry

The cyclic voltammetry, convolution voltammetry, potentiostatic electrolysis and open circuit potential time curve after electrolysis, current time curve at potential step, potential time curve at current step, X ray diffraction, EDAX, electron probe microanalysis were used to investigate the electrode processes of the reduction of rare earth ions on inert electrodes and alloying electrodes in molten chlorides and fluorides. The free energies of formation for the intermetallic compounds, the diffusion coefficients of rare earth ions in the melt, the diffusion coefficients of rare earth atoms in the alloy phases were determined. The alloys of rare earth with iron, cobalt, nickel, …

Go to article

Polymer Electrolyte Fuel Cell Powered Vehicles, Naichao Li, Baolian Yi May 1997

Polymer Electrolyte Fuel Cell Powered Vehicles, Naichao Li, Baolian Yi

Journal of Electrochemistry

The background, status and commercialization prospect of polymer electrolyte fuel cell vehicles are surveyed in this paper. The technology of this cell and system used in vehicles is discussed.

Go to article

Carboxymethylethanolamine, A Biomarker Of Phospholipid Modification During The Maillard Reaction In Vivo, Jesus R. Requena, Mahtab U. Ahmed, C. Wesley Fountain, Thorsten P. Degenhardt, Sharanya Reddy, Cliff Perez, Timothy J. Lyons, Alicia J. Jenkins, John W. Baynes, Suzanne R. Thorpe May 1997

Carboxymethylethanolamine, A Biomarker Of Phospholipid Modification During The Maillard Reaction In Vivo, Jesus R. Requena, Mahtab U. Ahmed, C. Wesley Fountain, Thorsten P. Degenhardt, Sharanya Reddy, Cliff Perez, Timothy J. Lyons, Alicia J. Jenkins, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Nepsilon-(Carboxymethyl)lysine (CML) is a stable chemical modification of proteins formed from both carbohydrates and lipids during autoxidation reactions. We hypothesized that carboxymethyl lipids such as (carboxymethyl)phosphatidylethanolamine (carboxymethyl-PE) would also be formed in these reactions, and we therefore developed a gas chromatography-mass spectrometry assay for quantification of carboxymethylethanolamine (CME) following hydrolysis of phospholipids. In vitro, CME was formed during glycation of dioleoyl-PE under air and from linoleoylpalmitoyl-PE, but not from dioleoyl-PE, in the absence of glucose. In vivo, CME was detected in lipid extracts of red blood cell membranes, approximately 0.14 mmol of CME/mol of ethanolamine, from control and diabetic subjects, …

Go to article

Grand Canonical Monte Carlo And Modified Singlet Integral Equations For The Density Profile Of A Yukawa Fluid Near A Planar Wall, Douglas Henderson, Wilmer Olivares-Rivas, Leo Degreve, Jacqueline Quintana May 1997

Grand Canonical Monte Carlo And Modified Singlet Integral Equations For The Density Profile Of A Yukawa Fluid Near A Planar Wall, Douglas Henderson, Wilmer Olivares-Rivas, Leo Degreve, Jacqueline Quintana

Faculty Publications

Results for the density profile for Yukawa molecules near a hard wall and an exponential attractive wall are presented for Grand Canonical Monte Carlo (GCMC) simulations, for the singlet hypernetted chain (HNC) integral equation and for a modified version of the Lovett–Mou–Buff–Wertheim (LMBW-1) which uses the exact contact value theorem. The results of the standard singlet HNC are quite poor. If the LMBW equation is modified (but still using the bulk direct correlation function) the results at high temperature become reasonable. However, the results at low temperatures, close to the bulk coexistence curve, are only a partial improvement. The contact …

Go to article

The Voltammetry Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson May 1997

The Voltammetry Of Mn@C82, Mark Anderson, Harry Dorn, Paul Burbank, James Gibson

Mark R. Anderson

No abstract is currently available.

Go to article

Stereoselective Adsorptive Bubble Process, Daniel W. Armstrong, Yubing Tang May 1997

Stereoselective Adsorptive Bubble Process, Daniel W. Armstrong, Yubing Tang

Chemistry Faculty Research & Creative Works

Process for enriching the concentration of an enantiomer (or a diastereomer) in a mixture of optically active isomers. The process includes preparing a solution containing the mixture of the optically active isomers and a chiral collector in which the chiral collector and the enantiomer (or diastereomer) are associated with each other. A gas is bubbled through a pool of the solution to form a foam, the surfaces of the bubbles in the foam having the chiral collector and the enantiomer (or diastereomer) preferentially adsorbed thereto so that the concentration ratio of the optically active isomers at said bubble surfaces differs …

Go to article

Celluloid Blackness : Race, Modernity, And The Conflicted Roots Of American Cinema (1915-1939), Lincoln Farr May 1997

Celluloid Blackness : Race, Modernity, And The Conflicted Roots Of American Cinema (1915-1939), Lincoln Farr

Honors Theses

Introduction: "The Problem of the Twentieth Century" In a full page interview in the New York Times on May 29, 1912, the Swiss psychiatrist Dr. Carl G. Jung told the American people, "It seems to me that you are about to discover yourselves. You have discovered everything else-all the land of this continent; all the resources, all the hidden things of nature."Jung used the interview to address the American people, at a moment which he somehow recognized as crucial in the development of human civilization. America, the "tragic" country which he struggled to comprehend, would soon become the harbinger of …

Go to article

Signal Transduction Pathways In Volvox Carteri, Heide Girardin May 1997

Signal Transduction Pathways In Volvox Carteri, Heide Girardin

Honors Theses

The green alga Volvox carteri exhibits a virtual absence of protein synthesis in the dark, but begins synthesizing proteins necessary for growth and development almost immediately after exposure to the light. The regulation of protein synthesis in this system is known to be translational since extracts prepared in the dark have identical pools and quantities of mRNA as extracts prepared in the light (Kirk and Kirk, 1983). Exploration of the mechanism of translational regulation has led us to consider the importance of signal transduction pathways. By using a variety of commercially available drugs that affect specific components of known signaling …

Go to article

Laser-Initiated Decomposition Products Of Indocyanine Green (Icg) And Carbon Black Sensitized Biological Tissues, John M. Kokosa, Andrzej Przyjazny, Kenneth Eugene Bartels, Massoud Motamedi, Donald J. Hayes, David B. Wallace, Christopher J. Frederickson May 1997

Laser-Initiated Decomposition Products Of Indocyanine Green (Icg) And Carbon Black Sensitized Biological Tissues, John M. Kokosa, Andrzej Przyjazny, Kenneth Eugene Bartels, Massoud Motamedi, Donald J. Hayes, David B. Wallace, Christopher J. Frederickson

Chemistry & Biochemistry Publications

Organic dyes have found increasing use a s sensitizers in laser surgical procedures, due to their high optical absorbances. Little is known, however, about the nature of the degradation products formed when these dyes are irradiated with a laser. Previous work in our laboratories has shown that irradiation of polymeric and biological tissues with CO2 and Nd:YAG lasers produces a host of volatile and semivolatile by-products, some of which are known to be potential carcinogens. This work focuses on the identification of the chemical by-products formed by diode laser and Nd:YAG laser irradiation of indocyanine green (ICG) and carbon black …

Go to article

Thermal Decomposition Reactions Of Acetaldehyde And Acetone On Si(100), J.L. Armstrong, J.M. White, Marjorie Langell May 1997

Thermal Decomposition Reactions Of Acetaldehyde And Acetone On Si(100), J.L. Armstrong, J.M. White, Marjorie Langell

Marjorie A. Langell Publications

We have studied the thermal interactions of acetone and acetaldehyde on Si(100), both sputtered and annealed, using high resolution electron energy loss spectroscopy, (HREELS), x-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). There is no carbonyl stretch in HREELS and the C and O(1s) XPS peaks reflect two different carbonyl processes, one involving bond cleavage, the other a reduction of the C–O bond order. Hydrogen TPD gives a peak at 840–850 K which is as much as threefold more intense than from H-saturated Si(100). SiO desorbs near 1050 K and XPS shows total loss of oxygen and …

Go to article

41. Akio Nakajima, 1921-1997, Otto Vogl, Toshio Hayashi May 1997

41. Akio Nakajima, 1921-1997, Otto Vogl, Toshio Hayashi

Otto Vogl

No abstract provided.

Go to article

Fragment Distributions For Highly Charged Systems, C. Williams, W. G. Lynch, C. Schwarz, M. B. Tsang, W. C. Hsi, M. J. Huang, D. R. Bowman, J. Dinius, C. K. Gelbke, D. O. Handzy, G. J. Kunde, M. A. Lisa, Graham F. Peaslee, L. Phair, A. Botvina, M-C. Lemaire, S. R. Souza, G. Van Buren, R. J. Charity, L. G. Sobotka, U. Lynen, J. Pochodzalla, H. Sann, W. Trautmann, D. Fox, R. T. De Souza, N. Carlin May 1997

Fragment Distributions For Highly Charged Systems, C. Williams, W. G. Lynch, C. Schwarz, M. B. Tsang, W. C. Hsi, M. J. Huang, D. R. Bowman, J. Dinius, C. K. Gelbke, D. O. Handzy, G. J. Kunde, M. A. Lisa, Graham F. Peaslee, L. Phair, A. Botvina, M-C. Lemaire, S. R. Souza, G. Van Buren, R. J. Charity, L. G. Sobotka, U. Lynen, J. Pochodzalla, H. Sann, W. Trautmann, D. Fox, R. T. De Souza, N. Carlin

Faculty Publications

Charge and transverse energy distributions for intermediate mass fragments have been extracted for central 84Kr+197Au collisions at E/A=35-400 MeV. The slopes of the measured fragment charge distributions decrease monotonically with incident energy, consistent with the expectations for highly charged systems, but not with recent critical exponent analyses. Statistical model calculations, which reproduce the experimental trends, suggest that post-breakup fragment secondary decays alter significantly the observed charge distributions. Radial expansion velocities extracted from these calculations follow the systematics of Au+Au collisions.

Go to article

In Situ Observations Of Air Traffic Emission Signatures In The North Atlantic Flight Corridor, Hans Schlager, Paul Konopka, P. Schulte, U. Schumann, H. Ziereis, F. Arnold, M. Klemm, Donald E. Hagen, Philip D. Whitefield, J. Ovarlez May 1997

In Situ Observations Of Air Traffic Emission Signatures In The North Atlantic Flight Corridor, Hans Schlager, Paul Konopka, P. Schulte, U. Schumann, H. Ziereis, F. Arnold, M. Klemm, Donald E. Hagen, Philip D. Whitefield, J. Ovarlez

Physics Faculty Research & Creative Works

Focussed aircraft measurements have been carried out over the eastern North Atlantic to search for signals of air traffic emissions in the flight corridor region. Observations include NO, NO2, HNO3, SO2, O3, H2O, total condensation nuclei (CN), and meteorological parameters. A flight pattern with constant-altitude north-south legs across the major North Atlantic air traffic tracks was flown. Signatures of air traffic emissions were clearly detected for NOx, SO2, and CN with peak concentrations of 2 ppbv, 0.25 ppbv, and 500 cm-3, respectively, exceeding background …

Go to article

Computer Modeling Of Molecular Vibration Frequencies And Its Application To The Modeling Of Silane Compounds, Ryan T. Merrell May 1997

Computer Modeling Of Molecular Vibration Frequencies And Its Application To The Modeling Of Silane Compounds, Ryan T. Merrell

Honors Capstone Projects and Theses

No abstract provided.

Go to article

Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone May 1997

Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.

Go to article

Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell May 1997

Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell

Undergraduate Honors Capstone Projects

The pyrrolo[2,3-d] pyrimidine ring systems are present in a variety of antibacterial/anticancer compounds. A scarcity of natural sources has made necessary the need for researchers to find more efficient methodologies to synthesize such compounds.1 The Edstrom research group is currently exploring new routes to these compounds, varying the protecting groups and the precursors used to make them.

Go to article

Xenon Isotope Record Of Nucleosynthesis And The Early Solar System, Jauh-Tzuoh Lee, Bin Li, Oliver Manuel May 1997

Xenon Isotope Record Of Nucleosynthesis And The Early Solar System, Jauh-Tzuoh Lee, Bin Li, Oliver Manuel

Chemistry Faculty Research & Creative Works

No abstract provided.

Go to article

A Study Of Combustion Profiles Of Co-Fired Coal/Biomass/Limestone Samples In A Fluidized Bed Combustor, Beverly Campbell May 1997

A Study Of Combustion Profiles Of Co-Fired Coal/Biomass/Limestone Samples In A Fluidized Bed Combustor, Beverly Campbell

Masters Theses & Specialist Projects

Concerns over declining landfill space and a renewed interest in waste-toenergy technologies have increased the possibilities of co-firing different types of fuels in atmospheric fluidized bed combustion systems. The laboratory sized atmospheric fluidized bed combustor (AFBC) at Western Kentucky University was designed to serve as a highly flexible research and development facility to gain operating experience, evaluate combustion performance, and estimate the effect of flue gas emissions on the atmosphere. The operating conditions for the AFBC system are similar to those used at the TVA 160-MW AFBC Pilot Plant located near Paducah, Kentucky. AFBC systems are ideal for co-firing because …

Go to article

Mass Balance Of Major, Minor And Trace Elements During Afbc Combustion Of Fuels, Qianwen Cao May 1997

Mass Balance Of Major, Minor And Trace Elements During Afbc Combustion Of Fuels, Qianwen Cao

Masters Theses & Specialist Projects

The proposed ASTM procedures for the determination of 13 major and minor., and 11 trace elements, in solid coal and coke combustion residues by inductively coupled plasma-atomic emission spectrometry (ICP-AES) were checked for routine use. In this study, the ICP analysis values and XRF analysis values of major and minor elements in two kinds of coal and two kinds of limestone were compared. It was shown that over 95% closure of the mass balances of the 24 major, minor, and trace elements was obtained with the proposed ASTM procedure. Also, it was demonstrated that trace elements may be lost through …

Go to article

Development Of Methods For The Determination Of Major And Minor Elements And Hydrocarbon Residues In Solid Combustion Products, Xiaoliu Chi May 1997

Development Of Methods For The Determination Of Major And Minor Elements And Hydrocarbon Residues In Solid Combustion Products, Xiaoliu Chi

Masters Theses & Specialist Projects

Methods for the determination of inorganic constituents in coal fly ash by glow discharge spectrometry (GDS) and for the extraction of the organic compounds from coal and ash by supercritical fluid extraction (SFE) at temperatures below 150°C are reviewed. The inorganic elements studied included Al, Ca, C, Cu, Fe, Mg, Mn, P, S, Si and Ti. The organic compounds were measured by weight loss of the sample. The goal of this research was to find easier and faster ways to measure the concentration of inorganic elements in coal ash and to measure extractability of the coal itself, to make coal …

Go to article

Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard Apr 1997

Ac-Mode Atomic Force Microscope Imaging In Air And Solutions With A Thermally Driven Bimetallic Cantilever Probe, Andrew C. Hillier, Allen J. Bard

Andrew C. Hillier

An ac imaging mode for atomic force microscopy ~AFM! has been developed that employs a thermally driven bimetallic cantilever to sense surface topography. Oscillations are induced in a composite cantilever, comprising a Si3N4 layer and Au overcoat, by local heating with a resistive wire heater placed in close proximity to the cantilever. Cantilever bending occurs upon heating due to the difference in thermal expansion coefficients of the Si3N4 and Au layers. The magnitude of this bending is a function of the heat input, the cantilever geometry, the frequency of the excitation, and the thermal properties of the surrounding medium. A …

Go to article

First Prev Next Last