SGER_ Nanoporous Semicrystalline Block Copolymer Blends for Gas Transport Applications
Web Personalization and Mining Using Robust Fuzzy Clustering Methods
SBIR Phase I_ A Wireless Polyvinylidene Flouride _PVDF_ Strain Sensor for Infrastructure Monitoring
Generating Shared_Setups for Enabling Mass Customization
US_Japan Joint Seminar_ Abnormal Flow Phenomena in Turbomachines_From Avoidance to Suppression and Control
SBIR Phase I_ A Face Identification System Using a Novel 3D Camera
CAREER_ Passive and Active Damping Control for Large Civil Structures
Microwave Methods for Lower Fat Patties and Meatballs
Diatoms and Cold Water_ A Novel Hypothesis Regarding Nitrate Uptake and Reduction
University of Maryland Center for Environmental Sciences
U.S._Brazil Cooperative Research_ Chaos Theory Applied to Communication
Research Internships in Telecommunications Engineering _RITE_ Site
ERC_ Engineering Research Center for Computer_Integrated Surgical Systems and Technology
Developing Models of Melt Transfer in Migmatites _ A Pilot Study
Coordinating U.S. Globec_ The Scientific Steering Committee
Support Services Related to NSF Program Solicitation_ NSF 98_103_ _quot_Faculty Early Career Development _CAREER__quot_ Program.
Suppliment_ Parasitism of Bloom_Forming Dinoflagellates_ Host Specificity and Ecological Implications
Acquisition of a Cryogenic Near_Field Scanning Microwave Microscope
U.S._Japan Cooperative Science_ Ecophysiology of Larval_Stage Dispersal in Estuarine Fishes
SBIR Phase II_ Oxidation of Organic Compounds in Water with Cavitating Jets
U.S._Germany Cooperative Research_ Numerical Simulation of Complex Flows Using Asymptotic_Based Schemes
SBIR Phase I_ Software Development for Automatic Scanning and Analysis of Fluorescent Labeled Prostate Cancer Cells
Numerical Modeling of Neutron Star Binaries_ Supernovae and Cosmology
Acquisition of a State of the Art Electron Probe Microanalyzer
A Multi_User_ Research and Training Ultracentrifugation Facility
Community College of Baltimore County_ Catonsville
Improving Integrated Learning of the Sciences Using a MobileComputer_Interfaced Instrumentation Laboratory
Arithematic Manifolds_ Geodesics_ Spectra and L_Functions
Bluff_Body Transient Wind Effects via CFD
GOALI_ Microscopic Basis of Polymer_Supercritical Fluid Phase Behavior_ Polymer_Solvent Interactions and Chain Stiffness
RUI_ Reducing the Cost of Regression Testing
Numerical Methods for III_Posed Problems and Large Scale Eigenvalue Programs
In Situ Biophysical Approach to Cytoskeletal Mechanics and Regulation
FASEB Conference_ Renal Hemodynamics _ Integration of Entegration of Endothelial_ Epithelial _amp_ Vascular_ on June 27 _ July 2_ 1998_ at Saxton_apos_s River_ Vermont
Federation of Amer Societies For Exper Biology
NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY
Electronic Commerce for Next Generation Manufacturing Systems_ 5th Annual Manufacturing Technology Conference_ April 21_22_ 1998_ NIST_ Gaithersburg_ Maryland
Carbohydrate Engineering for Generating Sialylated Glycoproteins in Insect Cells _Collaborative Research_
Instabilities Associated with an Electron Beam in the Presence of Intrinsic Alfven Waves
Experimental Software Systems_ Hardware_Software Co_Design of an Experimental Real_Time Operating System and a Microcontroller Architecture
Use of Molecular Techniques to Assess Diversity Among the Bdellovibrios
NSF Minority Postdoctoral Research Fellowship for 1998
Development of a Multiphase _quot_3_D__quot_ Boundary_Layer Flow Visualization Technique
Henry M Jackson Fdn for Advmt of Military Medicine
Collaborative Research_ Melanopsin _ A Novel Deep Brain Opsin
The Realization of a Retinal Prosthesis for the Totally Blind
Retinal Neurobiology and Visual Processing_ 1998 FASEB Summer Research Conference_ Saxtons River_ VT
U.S._Brazil Workshop on Techno_Regions_ Science_ Technology _amp_ Regional Development_Past_ Present and Future Challenges_ May 7_10_ 1998_ Itaipava_ Brazil
Role of Cyclic Nucleotide_Gated Channels in the CNS
NSF_CGP Fellowship_ Reaction Kinetics and Mechanisms for the Reduction of a Copper Oxide Surface with H Atoms
Analysis of Wind Loads and Structural Resistance Data from Town of Southern Shores Low_Rise Structure
U.S._France Cooperative Research_ Concentration Flux Measurements and Modeling of Scalar Transport in Bounded Turbulent Shear Flows
Dissertation Research_ History of Evolutionary Biology in Germany from the 1880s through the 1920s
REU Site_ SURFing the Materials Science and Engineering Lab_ A NIST_NSF Partnership
Researches on Charles Darwin_apos_s Geological Work
Coping with Darkness_ The Physiological Responses of Marine Microalgae to Aphotic Conditions and their Ecological Implications
1998 FASEB Conference on _quot_Protein Phosphatases_quot_ to be held on June 28_July 3_ 1998_ at Copper Mountain Colorado.
U.S._Egypt Cooperative Research_ Environmental Monitoring of Pesticides by Biosensors
The Spatial Dimension of Adsorption and Reaction of Metal Surfaces
CAREER_ Orbital Dynamics of Solar System Dust
Correlative Studies of Dayside Transients
SBIR Phase II_ Diatom Transformation for Product Enhancement
Making the Case for Science to the Reading Community
The Capabilities and Limitations of Atomated Discovery
Support Services for DUE Programs _Task Order ATE Program Support_ for Contract CPO95_96088
Technology Education Leadership Project _TELP_
Reductive Dual Pairs in Exceptional Groups_ Cohomology_ and Unipotent Representations
Collaborative Research_ UV Effects on Marine Production by Bacteria and Phytoplankton_ Assessing the Impact of UVB
SBIR PHASE II_ High Temperature Superconducting Materials Development for High Power Radio Frequency and Microwave Components
FASEB Summer Research Conference on Yeast Chromosome Structure_ Replication and Segregation_ Snowmass Village_ CO
CONF_ Sixth FASEB Summer Conference on _quot_Mechanisms in Plant Development_quot_ August 15_20_ 1998_ Saxton_apos_s River_ Vermont
NIH_AAOS Workshop on New Engineering Technology Transfer in Orthopaedics
Dissertation Research_ From Quantum Revolution to Institutional Transformation_ Edward Condon and the Dynamics of Pure Science in America_ 1928_1954
Mechanics of the Interaction between Concrete and FRP Reinforcing Elements
Riometry in Antarctica and Conjugate Regions
SBIR Phase I_ Integrated Diagnostics for Operations and Maintenance of Installed Systems
Determination of Optimum Radiolytic Treatment Methodologies _lt_br_gt_for Remediation of PCB Contaminated Sites
U.S._Egypt Cooperative_ Feasibility Study of Biomarkers for Hepatocellular Carcinoma in Egypt
Environmental Effects on Non_Self_Interest Behavior
POWRE_ Seagrass Induced Pore Water Advection in Permeable Sediments
Sinai_Ruelle_Bowen Measures for Non_Hyperbolic Attractors
Dr. Martin Luther King Jr. Middle School
Drug Discovery_ Biodiversity Conservation and Sustainable Development
Functional Characterization of a Novel Mammalian Homologue of eIF4E
University of Maryland Biotechnology Institute
Maryland Collaborative for Teacher Preparation_ Institutionalization and Assessment of Innovative Teacher Preparation Programs
SBIR Phase I_ Equipment and Experiment Resources for Fermentation Technology
Mathematical_Computational Tools for Mapping Brain Data Bases
SBIR Phase II_ Ballistics Matching Using Three Dimensional Images of Bullets and Cartridge Cases
CAREER_ Generative Designer Assistance Tools
Technology_Based Problem_Solving Method in Learning
Interior Point Methods Semidefinite Programming
The Introduction of Diversity into a Biology Curriculum
ONR_NSF_AWM Workshops for Women Graduate Students _amp_ Postdoctoral Mathematicians
SGER_ Stability of Self_Assembled Microstructures at KilobarPressures
CAREER_ Software Synthesis for Real_time Signal Processing Systems
U.S._Mexico Workshop_ The Renormalization Group at the Turn of the Millennium_ January 10_15_ 1999_ Taxco_ Mexico
Institute for Learning Innovation Incorporated
Adults Supporting Kids with Science _ASK with Science_
FASEB_ Summer Research Conference Folate_ B12_ and One_Carbon Metabolism to be held from August 1_6_ 1998 at Snowmass Village_ Colorado
A Computational and Molecular Modeling Laboratory to Strengthen a Discovery_Based Chemistry Curriculum
Collaborative Research_ Global Leadership and Organizational Behavior Research Program _GLOBE_
Time_Resolved IR Studies of Organic Reactive Intermediates
POWRE_ How Race Matters_ Global Perspectives on Ethnicity and Economic Inequality
Elementary Particle Theory and Quantum Field Theory
Powre_ Collaborative Research_ Developing a Theory of Buyer_Seller Networks
Biochemistry of Signal_Responsive Transcription in Plants
_quot_Hard_quot_ and _quot_Soft_quot_ Knowledge in High_Hazard Industries
Acquisition of a Multi_User Scanning Laser Confocal for Science and Engineering Research at Hopkins University
WORKSHOP_ Language Engineering Workshop for Students and Professionals Integrating Research and Education _WS98_
SBIR Phase II_ Computer Interactive Plant Biotechnology Education
Natural Scenes and the Design of the Color Visual Systems of Marine Animals
CAREER_ Space_Time Patterns in Snowmelt_ Research and Education for Hydrologic Forecasting
The Thermodynamics of Protein Separations _Collaborative Research_
Titanic Science_ Exploring New Methods of Interpretation
Momentum and Scalar Flux Measurements to Study LES Modeling in Turbulent Shear Flows
Cooperative Steady_Hand Augmentation of Human Skill in Micromanipulation Tasks
Proposal Processing for the Knowledge and Distributed Intelligence Initiative _KDI_
Optimization Techniques for Problems Arising in Design and Other Engineering Applications
SBIR Phase I_ Intelligent Surveillance Camera
Acquisition of Chromatographic Instrumentation
Protein Purification Using Novel Methods for Buffer Focusing Chromatography
Experiencing Geometry_ Enhancing Prospective Elementary and Middle School Teacher
Conference_ Neurobiology of Entrainment Meeting Support_ July 11 thru July 16_ 1998_ Snowmass_ CO
Support Services for LExEn Proposal Processing
Decision Support for Flow in Porous Media_ Optimal Sampling for Data Assimilation
Technical Assistance to the Engineering Directorate in Program Evaluation
Conference_ Travel Support for the 11th International Workshop for Plant Membrane Biology in Cambridge_ England_ on August 9_14_ 1998
GEM_ The Role of Ring Current Composition in the Recovery Rate of Magnetic Storms
The Internet Science Institute_ A Web_Based Method of Involving Students in Scientific Inquiry
SGER_ Effects of Wildfires on Soil Methane Fluxes in Florida Pine Plantations
Understanding the Basis for Metal Ion Specificity in Fe_ andMn_Superoxide Dismutases_ Learning to Make Bound Metal IonsCatalytically Active
A Paradigm for Inexpensive Service Robots
RUI_ Stability of Spacetimes with Mild Singularities or Cauchy Horizons
Sequencing of Arabidopsis Chromosome 2 _and beyond__ and Development of Resources for Arabidopsisgenome Analysis
US_India Cooperative Research_ The Effects of Realistic Eurasian Snow Cover on the Indian Monsoon_ A Numerical Experiment with A Regional Model
Workshop_ Annual Telluride Workshop on Neuromorphic Engineering_ June 29 thru July 19_ 1998_ Telluride_ CO
Complex Manifolds and Meromorphic Mappings
Collaborative Project_ Astrophysics of Early_Type Dwarf Galaxies
TASK ORDER _2_ Coordination and Technical Assistance for the Urban Research Initiative _URI_
POWRE_ Exploration of Applying Statistical Process Control Strategies to Simulated Annealing Optimization Techniques
FASEB Summer Conferenence_ Molecular Biophysics of CellularMembranes_ to be held in Saxton_apos_s River_ Vermont_ August 1_6_ 1998
Efficient Numerical Methods for Unsteady Viscous Incompressible Flows
GEM_ Ring Current and Radiation Belt Loss
NSF Postdoctoral Fellowships in Science_ Mathematics_ Engineering _amp_ Technology Education _PFSMETE_
Using Information in Mathematics and Science
Strengthening the Role of Soils in the GLOBE Student_Teacher_Scientist Partnership
The Psychological Dynamics of Radical Social Change_ A Longitudinal Analysis of Employed and Unemployed Ukrainian Men and Women
Petrologic and Isotopic Investigations of Chemically Reactive Fluid Flow During Metamorphism
SGER_ Development of a Novel Approach for the In Situ Analysis of Transcription Factor_DNA Complexes
Undergraduate Research Training at Towson University
RUI_ An Ultrastructural Analysis of the Development of Pigment Pattern in Zebrafish
The Montgomery County Public Schools_apos_ _MCPS_ planning grant
U.S._Japan Joint Seminar_ Minimal Surfaces_ Geometric Analysis_ and Symplectic Geometry
CAREER_ Towards a New Generation of Multimedia Storage Systems
FASEB Summer Conference_ Lipid Modification of Proteins to be held August 8_13_ 1998 Snownmass Village_ Colorado
The Consortium for Statewide Biotechnology Education
NSF_CGP Fellowship_ Growth and Characterization of InGaN Active Layers for Improved Blue_Emitting Laser Diodes
Devils from Hell_ Gunpowder Weaponry During the Hundred Years War
Electrochemical Deposition of Metals on Silicon
Magnetized States of Quantum Spin Chains
LTREB_ Community Ecology on Rocky Shores_ Long_Term Research in the Subtidal Zone _Massachusetts_ 1978 _ 2003_
RUI Protein Conformation_ New Methods for Global Optimization and Parameter
Meeting_ Mechanisms of Nucleic Acid Enzymes_ June 13_18_ 1998_ at Saxton_apos_s River_ Vermont
Free Choice Learning_ Accessing the Informal Science Education Infrastructure
Sudbury Igneous Complex_ The Ultimate Test of the Null Hypothesis
CSEDI Collaborative Research_ The 190Pt_1860s System as a Test of Core_Mantle Interaction_ Phase III
SBIR Phase I_ A Fully Automatic Rapid Prototyping System Using a Novel Rapid 3D Camera
Transmission Conflict in X _ Y Chromosomes and Consequences to Heritable Variation in Fitness in Diopsid Dipterans
Associate Degree for Manufacturing Technicians_ Institutionalizing Change in Technician Education by Expanding a _quot_Work in Progress_quot_
Rhenium_Osmium Isotope Study of the Mantle
LEXEN_ Microbial Adaptation to High Temperature and Pressure
NSF_CGP Fellowship_ A Japan _U.S. Attack on the Unstable Brown_Peterson Homology of Spaces
CISE Research Instrumentation_ Computational Techniques for 3_D Modeling and Analysis of Infrared and MRI Image Sequences
A Study of the Cultural Models of Pfiesteria Piscicida
East Coast Computer Algebra Day_ April 25_ l998_ U.S. Naval Academy_ Annapolis_ MD
The Role of Sequential Signals and Immunocompetence in Female Choice
Oxygen Escape from Mars_ Venus and Earth
FASEB Conference _ Transcriptional Regulation In Cell Growth and Development To Be Held In Snowmass_ CO on July 25_30_ 1998.
Doctoral Dissertation Research_ An Experimental Analysis of Adpative Learning
Implementation of Nanotechnology Studies in the Undergraduate Curriculum
Support for the Directorate of Mathematical and Physical Science for Proposal Processing Support for the ProfessionalOpportunties for Women in Research and Engineering _POWRE_.
Collaborative Research_ The Demand for Female Labor
SBIR Phase I_ Materials for Structural Vibration Avoidance
Proposal Processing and Data Entry Support for the Digital Libraries Initiative_Phase 2
Intrahousehold Nutrition Patterns in the Marshall Islands
Support Services for DUE Programs _Task Order _171 for CETP Program_ for Contract CPO_95_96088
Workshop on Computational Aerosciences in the 21st Century_ Hampton_ VA
Individiual Award_ Evaluator for International _quot_TIE_quot_ Program between Microcontamination Control Center and QUESTOR_ Belfast_ Northern Ireland
A Comprehensive Approach to Increasing Minority Graduates in Science_ Engineering _amp_ Mathematics Through Innovative Pedagogy_ Technology _amp_ Research
MRI_ Acquisition of a Phase Doppler Anemometer for Engineering Education and Research in Multiphase Flow
US_Turkey Cooperative Research_ Investigation of the Novel Electronic_ Stuctural and Dynamical Properties of Cubane and Various Cubane Derivatives
187Re_187Os_ 190Pt_186Os_ 34S_32S Isotopic Systematics of the Subcontinental Mantle of the Western United States
Conference on Auctions and Infrastructure to be Hosted by the University of Maryland in Spring 1998
Mathematical Sciences_ Research Experiences in Parallel Numerical Linear Algebra
VLSI Implementation of Computation Sensors for Visual Information Processing
International Research Fellow Awards_ Computational Fluid Dynamics Study of the Systemic to Pulmonary Shunt in Hypoplastic Left Heart Syndromes _amp_ Single Ventricles
SGER_ A Study of State Political Party Endorsement Systems in Gubernatorial Nominations
Development of Si Light Emitting Devices for Enabling Optical Interconnect Technology in Si Integrated Circuits
Geometric Algorithm Design and Implementation
Cobordism of Configuration Spaces and Its Applications
Workshop on October 15_16_ 1998 in Washington DC area_ Symposium for Information Technology and R_amp_D Program for the 21st Century
Center Evaluator for Texas A _amp_ M University Industry_ University Cooperative Research Center for Ergonomics
Support of the workshop _quot_Mathematical Cognition_quot__ Spring 1998 in Bethesda_ MD
National Institute of Health _NIH_NICHD_
Activation of C_F Bonds by Aryl Carbocations
Minority Institutions Infrastructure_ LEARN Laboratory_ based Educational and Research Network
Structure of Homeodomain Gene Regulatory Complexes
Decadal Variability and the Analysis of WOCE Upper Ocean Observations
Nutrition of Reef Corals_ Effects of Morphology_ Resource Availability_ and Water Flow
Measurement of Aerodynamic Performance of the Houston Ship Channel Bridge
CAREER_ Immuno_Optical Biosensors for Plasma Factors_ Application of TQM in Bioengineering Education
U.S._Germany Cooperative Research_ Kernel_Based Classifiers and Regression Algorithms
Fundamental Experimental Properties of Mesoscopic Systems
Probability and Combinatorial Structures
Chemical and Spectroscopic Studies of Nitrenium Ions and Related Species
Dissertation Research_ Three_Dimensional Comparisons of Craniofacial Growth Patterns in Modern Humans and Neandertals
Combustion Reactions Induced by Ball Milling
Chaos with Multiple Positive Lyapunov Exponents
Social Reasoning About Group Inclusion and Exclusion
Representations of the Fundamental Group and Connections with Deformation Theory_ Geometry and Integrable Systems
Accreditation Board for Engineering and Technology Inc _ABET_
Integration of Wind and Sound Cues in the Bat Evasion System of Praying Mantises
Challenges and Promise of In Situ Sensing for Nowcasting_ Forecasting and Predicting Environmental Trends in Coastal Ecosystems_ A Workshop Proposal for Multi Agency Support
Doctoral Dissertation Research_ Economic Development in the Liberal State
Support Assistance for the SBER_apos_s Economic_ Decision _amp_ Management Sciences Cluster
Shaping the Future_ Creating Collaborations for Undergraduate Science_ Mathematics_ Engineering and Technology
Numerical and Theoretical Analysis of Shallow Water Flow with Applications to the Global Oceanic Circulation
Computational Methods for the Simulation of Chemical Vapor Deposition on Rough Surfaces
SGER_ An Analysis of Japanese Elementary School MathematicsTeachers_apos_ Manuals
Topology and Dynamics of Moduli Spaces of Geometric Structures
Family Stability in Cooperative Breeding Primates
CONF_ 57th Society for Developmental Biology Annual MeetingPalo Alto_ California_ June 20_25_ 1998
Study Feasibility of Accreditation of Programs in Computer Information Science_Systems_Technology
Collaborative Research_ Fundamental Investigation of Modeling for LES of Atmospheric Boundary Layer Flow Near the Land_Atmosphere Interface
Development of Light Emitting Devices in Wide Band Gap MetalOxide_Nitride Systems using Pulsed Laser Deposition and Focused Ion Beam Technology
CAREER_ Integrated Environment for Interactive Rendering of Large_Scale Solid Models
_RUI_ Collaboration_ Quantitative Modeling of Cold_Atom Bose_Einstein Condensates and Atom Lasers
The Use of Gas Chromatography_Mass Spectrometry to Enhance the Undergraduate Laboratory Experience
SBIR PHASE II_ Intelligent Prevention and Information System for Earthquake_Induced Urban Fires _IPIS EF_
Regulation and Assembly of a Type III Protein Secretion Apparatus in Pseudomonas syringae
POWRE_ Metabolism of the Plant Hormone Indole_3_Acetic Acid During Somatic Embryogenesis
Parametric Design of Embedded Real_Time Systems
Regulation of Tryptophan Genes in Arabidopsis
Dissertation Research_ Direct and Indirect Effects of Plant Morphological Complexity on the Efficiency of Predation of Coccinella septempunctata L
Plant Physiology_ Phytohormone Research_ and Agricultural Herbicides 1920_1950
Collaborative Research_ _quot_The Impact of Education Finance Equalization on Students_ Teachers_ Schools and State Governments_quot_
Proposal Processing and Data Entry Suppport for Course_ Curriculum and Laboratory Improvement _CCLI_ under NSF Contract DAS_9816737
Experimental Study of Criticality _amp_ Crossover Phenomena in _lt_br_gt_Complex Fluid Mixtures
Uniformity and Diversity in Multi_Institutional Collaborations in Science
CAREER_ Evolution of the Locomotor Apparatus in Arthropods
Purchase of a Flow Cytometer for the Large_scale Assessment of Biogenic Particles in Estuarine and Coastal Systems
Retrospective Analysis of Dispersive and Retentive Behaviors of Young_of_the_Year Estuarine Fishes_ Are Fish Otoliths Environmental Chronometers_
Magnetospheric States and State Transitions
Learning and Evaluating Science through Art_ Scientific Illustrators Work with Teachers
FASEB Conference_ Intracellular RNA Sorting_ Transport and Localization_ to be held in Snowmass_ Colorado_ June 6_11_ 1998
Contract CPO_9596088 Response to Task Order_172
Crystallographic Studies of Phosphoryl Group Transfer Reactions
Implementing Consumer Right_To_Know Provisions_ A Normative _amp_ Conceptual Analysis
n_Widths and Singular Perturbation Problems
Transition Pool Boiling Heat Transfer Mechanisms on a Strip Heater Using Microscale Heater Arrays
International Workshop on the Physics and Mechanics of Soil Liquefaction.
Affect and Processing of Negative Information
Asymptotic Problems for Stochastic Processes and PDE_apos_s
The Structure of the Universe Beyond 100 Mpc
Managerial Personality_ Organizational Climate_ and Customer Satisfaction
SBIR Phase II_ Design of a New and Improved Print Reading Machine for the Blind
Regularity Properties of Partial Differential Equations
American Association of Physics Teachers
Undergraduate Physics Programs for the 21st Century Conference
Solid_State Alloying and Amorphization of Immiscible Elements
CAREER_ Multivariate Visualization of Importance_Varying Data
Acquisition and Upgrade of X_ray Diffractometers at the University of Maryland
Technological Innovation and Policy Decision_Making_ Radio and Television Broadcasting in the United States_ 1910_1996
Openness_Secrecy_ Authorship_ Ownership_ Studies in the Technical_ Practical_ and Knowledge Traditions of Premodern and Early Modern Europe
Dissertation Research_ An Experimental Test of Fisher_apos_s Geometric Model of the Adaptive Process
Subcommittee on Construction and Building_ National Science and Technology Council
Intelligent Control_ A Dynamic Game Approach
U.S._Singapore Cooperative Research_ Database Integration in the Drosophila Developmental Pathway
CAREER_ Structural Basis of Bacterial Conjugation
The Fluorescence of Indole_ Tryptophan and Proteins
Seasonal Differences in Air_Snow Chemical Relationships at Summit_ Greenland
Investigation of Pairing Symmetry and Normal State Properties of Electron_Doped Copper Oxides