Glossary of Terms
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Glossary Physics (I-Introduction)
1 Glossary Physics (I-introduction) - Efficiency: The percent of the work put into a machine that is converted into useful work output; = work done / energy used [-]. = eta In machines: The work output of any machine cannot exceed the work input (<=100%); in an ideal machine, where no energy is transformed into heat: work(input) = work(output), =100%. Energy: The property of a system that enables it to do work. Conservation o. E.: Energy cannot be created or destroyed; it may be transformed from one form into another, but the total amount of energy never changes. Equilibrium: The state of an object when not acted upon by a net force or net torque; an object in equilibrium may be at rest or moving at uniform velocity - not accelerating. Mechanical E.: The state of an object or system of objects for which any impressed forces cancels to zero and no acceleration occurs. Dynamic E.: Object is moving without experiencing acceleration. Static E.: Object is at rest.F Force: The influence that can cause an object to be accelerated or retarded; is always in the direction of the net force, hence a vector quantity; the four elementary forces are: Electromagnetic F.: Is an attraction or repulsion G, gravit. const.6.672E-11[Nm2/kg2] between electric charges: d, distance [m] 2 2 2 2 F = 1/(40) (q1q2/d ) [(CC/m )(Nm /C )] = [N] m,M, mass [kg] Gravitational F.: Is a mutual attraction between all masses: q, charge [As] [C] 2 2 2 2 F = GmM/d [Nm /kg kg 1/m ] = [N] 0, dielectric constant Strong F.: (nuclear force) Acts within the nuclei of atoms: 8.854E-12 [C2/Nm2] [F/m] 2 2 2 2 2 F = 1/(40) (e /d ) [(CC/m )(Nm /C )] = [N] , 3.14 [-] Weak F.: Manifests itself in special reactions among elementary e, 1.60210 E-19 [As] [C] particles, such as the reaction that occur in radioactive decay. -
Hydrogen Bond Assisted Adhesion in Portland Cement-Based Materials
136 Cerâmica 57 (2011) 136-139 Hydrogen bond assisted adhesion in Portland cement-based materials (Adesão assistida por ligação de hidrogênio em materiais à base de cimento Portland) H. L. Rossetto1,2, V. C. Pandolfelli1 1Departamento de Engenharia de Materiais - DEMa, Universidade Federal de S. Carlos - UFSCar, Rod. Washington Luiz, km 235, S. Carlos, SP 13565-590 2Instituto de Física de S. Carlos, Universidade de S. Paulo - IFSC-USP, Av. Trabalhador São-Carlense 400, S. Carlos, SP 13566-590 [email protected] Abstract Adhesion is a physical-chemical parameter able to render innovations to Portland cement-based materials. However, this concept still lacks experimental evidence to underlie further developments in this subject. This work has demonstrated how distinct substances can impart different adhesion forces after evaluating the hydration degree and the mechanical strength of non-reactive cementitious materials. The substances capable of making tridimensional hydrogen bonds, such as water, for instance, were the most effective in providing cementitious samples with improved bending strength. It implies that water is not only important because of its role in cement hydration, but also because it develops adhesion between hydrated cementitious surfaces. More than speculating the fundamental understanding on adhesion in Portland cement-based materials, the present paper intends to stimulate thinking on how to take the benefits of the water confined between the hydrated cementitious surfaces as an in-built nanoadhesive, so far little explored, but at the same time so prone to yield high performance materials. Keywords: adhesion, hydrogen bond, mechanical properties, Portland cement. Resumo Adesão é um parâmetro físico-químico que pode promover inovações em materiais à base de cimento Portland. -
UNIVERSITY of CALIFORNIA, IRVINE Kinetic Studies Of
UNIVERSITY OF CALIFORNIA, IRVINE Kinetic Studies of Multivalent Nanoparticle Adhesion DISSERTATION submitted in partial satisfaction of the requirements for the deGree of DOCTOR OF PHILOSOPHY in Biomedical EnGineerinG by MinGqiu WanG Dissertation Committee: Assistant Professor Jered Haun, Chair Associate Professor Jun Allard Professor YounG Jik Kwon 2018 © 2018 MinGqiu WanG DEDICATION To my parents, for their unconditional love and support. ii TABLE OF CONTENTS DEDICATION.......................................................................................................................... II TABLE OF CONTENTS........................................................................................................ III LIST OF FIGURES .................................................................................................................. V LIST OF TABLES ................................................................................................................. VII ACKNOWLEDGMENTS ..................................................................................................... VIII CURRICULUM VITAE ........................................................................................................... X ABSTRACT OF THE DISSERTATION ............................................................................... XI 1. INTRODUCTION ........................................................................................................... 1 1.1. TARGET NANOPARTICLE ADHESION ............................................................................................ -
Adhesion and Cohesion
Hindawi Publishing Corporation International Journal of Dentistry Volume 2012, Article ID 951324, 8 pages doi:10.1155/2012/951324 Review Article Adhesion and Cohesion J. Anthony von Fraunhofer School of Dentistry, University of Maryland, Baltimore, MD 21201, USA Correspondence should be addressed to J. Anthony von Fraunhofer, [email protected] Received 18 October 2011; Accepted 14 November 2011 Academic Editor: Cornelis H. Pameijer Copyright © 2012 J. Anthony von Fraunhofer. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The phenomena of adhesion and cohesion are reviewed and discussed with particular reference to dentistry. This review considers the forces involved in cohesion and adhesion together with the mechanisms of adhesion and the underlying molecular processes involved in bonding of dissimilar materials. The forces involved in surface tension, surface wetting, chemical adhesion, dispersive adhesion, diffusive adhesion, and mechanical adhesion are reviewed in detail and examples relevant to adhesive dentistry and bonding are given. Substrate surface chemistry and its influence on adhesion, together with the properties of adhesive materials, are evaluated. The underlying mechanisms involved in adhesion failure are covered. The relevance of the adhesion zone and its impor- tance with regard to adhesive dentistry and bonding to enamel and dentin is discussed. 1. Introduction molecular attraction by which the particles of a body are uni- ted throughout the mass. In other words, adhesion is any at- Every clinician has experienced the failure of a restoration, be traction process between dissimilar molecular species, which it loosening of a crown, loss of an anterior Class V restora- have been brought into direct contact such that the adhesive tion, or leakage of a composite restoration. -
This Ubiquitous Carbon…
Engineering Physics Department Presents Dr. Cristian Contescu Senior Research Staff, Materials Science and Technology Division Oak Ridge National Laboratory This ubiquitous carbon… Abstract: After Stone Age, Bronze Age, and Iron Age, and after the Silicon Age of the informational revolution, the technologies of 21st century are marked by the ubiquitous presence of various forms of carbon allotropes. For a very long time, diamond and graphite were the only known carbon allotropes, but that has changed with the serendipitous discovery of fullerenes, carbon nanotubes, and graphene. Every ten or fifteen years scientists unveil new forms of carbons with new and perplexing properties, while computations suggest that the carbon’s family still has members unknown to us today. At a dramatically accelerated pace, new carbon forms find their place at the leading edge of scientific and technological innovations. At the same time traditional forms of carbon are being used in new and exciting applications that make our life safer, healthier, and more enjoyable. The 21st century may soon be recognized as the Age of Carbon forms. This educational talk will show how carbon, the fourth most abundant element in the Galaxy and the basis of life on Earth, was the engine of most important technological developments throughout the history of civilization. It will emphasize the ability of carbon atoms to generate a variety of mutual combinations and with many other chemical elements. These properties have placed carbon at the core of numerous inventions that define our civilization, while emerging new technologies open a rich path for value-added products in today’s market. -
Properties of Carbon the Atomic Element Carbon Has Very Diverse
Properties of Carbon The atomic element carbon has very diverse physical and chemical properties due to the nature of its bonding and atomic arrangement. fig. 1 Allotropes of Carbon Some allotropes of carbon: (a) diamond, (b) graphite, (c) lonsdaleite, (d–f) fullerenes (C60, C540, C70), (g) amorphous carbon, and (h) carbon nanotube. Carbon has several allotropes, or different forms in which it can exist. These allotropes include graphite and diamond, whose properties span a range of extremes. Despite carbon's ability to make 4 bonds and its presence in many compounds, it is highly unreactive under normal conditions. Carbon exists in 2 main isotopes: 12C and 13C. There are many other known isotopes, but they tend to be short-lived and have extremely short half-lives. Allotropes The different forms of a chemical element. Cabon is the chemical element with the symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. Carbon has 6 protons and 6 Source URL: https://www.boundless.com/chemistry/nonmetallic-elements/carbon/properties-carbon/ Saylor URL: http://www.saylor.org/courses/chem102#6.1 Attributed to: Boundless www.saylor.org Page 1 of 2 neutrons, and has a standard atomic weight of 12.0107 amu. Its electron configuration is denoted as 1s22s22p2. It is a solid, and sublimes at 3,642 °C. It's oxidation state ranges from 4 to -4, and it has an electronegativity rating of 2.55 on the Pauling scale. Carbon has several allotropes, or different forms in which it exists. -
“Mining” Water Ice on Mars an Assessment of ISRU Options in Support of Future Human Missions
National Aeronautics and Space Administration “Mining” Water Ice on Mars An Assessment of ISRU Options in Support of Future Human Missions Stephen Hoffman, Alida Andrews, Kevin Watts July 2016 Agenda • Introduction • What kind of water ice are we talking about • Options for accessing the water ice • Drilling Options • “Mining” Options • EMC scenario and requirements • Recommendations and future work Acknowledgement • The authors of this report learned much during the process of researching the technologies and operations associated with drilling into icy deposits and extract water from those deposits. We would like to acknowledge the support and advice provided by the following individuals and their organizations: – Brian Glass, PhD, NASA Ames Research Center – Robert Haehnel, PhD, U.S. Army Corps of Engineers/Cold Regions Research and Engineering Laboratory – Patrick Haggerty, National Science Foundation/Geosciences/Polar Programs – Jennifer Mercer, PhD, National Science Foundation/Geosciences/Polar Programs – Frank Rack, PhD, University of Nebraska-Lincoln – Jason Weale, U.S. Army Corps of Engineers/Cold Regions Research and Engineering Laboratory Mining Water Ice on Mars INTRODUCTION Background • Addendum to M-WIP study, addressing one of the areas not fully covered in this report: accessing and mining water ice if it is present in certain glacier-like forms – The M-WIP report is available at http://mepag.nasa.gov/reports.cfm • The First Landing Site/Exploration Zone Workshop for Human Missions to Mars (October 2015) set the target -
Usgs Water Data
USGS WATER RESOURCES ONLINE PLACES TO START USGS Water home page http://water.usgs.gov/ USGS Water data page http://water.usgs.gov/data/ USGS Publications Warehouse http://pubs.er.usgs.gov/ USGS National Real-Time Water Quality http://nrtwq.usgs.gov/ USGS Water Science Centers http://xx.water.usgs.gov/ (where “xx” is two-letter State code) USGS WATER DATA NWIS-Web http://waterdata.usgs.gov/ NWIS-Web is the general online interface to the USGS National Water Information System (NWIS). Discrete water-sample and time-series data from 1.5 million sites in all 50 States. Results from 5 million water samples with 90 million water-quality results are available from a wide variety of retrieval methods including standard and customized map interfaces. Time-series retrievals include instantaneous measurements back to October 2007, soon to include the longer historical record. BioData http://aquatic.biodata.usgs.gov/ Access to results from more than 15,000 macroinvertebrate, algae, and fish community samples from more than 2,000 sites nationwide. StreamStats http://streamstats.usgs.gov/ssonline.html A map-based tool that allows users to easily obtain streamflow statistics, drainage-basin characteristics, and other information for user-selected sites on streams. Water Quality Portal http://www.waterqualitydata.us/ A cooperative service sponsored by USGS, EPA, and NWQMC that integrates publicly available water-quality data from the USGS NWIS database and the EPA STORET data warehouse. NAWQA Data Warehouse http://water.usgs.gov/nawqa/data.html A collection of chemical, biological, and physical water quality data used in the National Water Quality Assessment (NAWQA) program, drawn partly from NWIS and BioData. -
Sp Carbon Chain Interaction with Silver Nanoparticles Probed by Surface Enhanced Raman Scattering
sp carbon chain interaction with silver nanoparticles probed by Surface Enhanced Raman Scattering A. Lucotti1, C. S. Casari2, M. Tommasini1, A. Li Bassi2, D. Fazzi1, V. Russo2, M. Del Zoppo1, C. Castiglioni1, F. Cataldo3, C. E. Bottani2, G. Zerbi1 1 Dipartimento di Chimica, Materiali e Ingegneria Chimica ‘G. Natta’ and NEMAS - Center for NanoEngineered MAterials and Surfaces, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy 2 Dipartimento di Energia and NEMAS - Center for NanoEngineered MAterials and Surfaces, Politecnico di Milano, via Ponzio 34/3, I-20133 Milano, Italy 3 Actinium Chemical Research srl, via Casilina 1626/A, 00133 Roma, Italy and INAF – Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy Abstract Surface Enhanced Raman Spectroscopy (SERS) is exploited here to investigate the interaction of isolated sp carbon chains (polyynes) in a methanol solution with silver nanoparticles. Hydrogen-terminated polyynes show a strong interaction with silver colloids used as the SERS active medium revealing a chemical SERS effect. SERS spectra after mixing polyynes with silver colloids show a noticeable time evolution. Experimental results, supported by density functional theory (DFT) calculations of the Raman modes, allow us to investigate the behaviour and stability of polyynes of different lengths and the overall sp conversion towards sp2 phase. 1 2 1. Introduction Linear carbon chains with sp hybridization represent one of the simplest one dimensional systems and have therefore attracted a great interest for many years [1, 2]. sp chains can display two types of carbon-carbon bonding: polyynes, chains with single-triple alternating bonds (…-C≡C- C≡C-…) and polycumulenes, chains with all double bonds (…=C=C=C=…). -
Agricultural Soil Carbon Credits: Making Sense of Protocols for Carbon Sequestration and Net Greenhouse Gas Removals
Agricultural Soil Carbon Credits: Making sense of protocols for carbon sequestration and net greenhouse gas removals NATURAL CLIMATE SOLUTIONS About this report This synthesis is for federal and state We contacted each carbon registry and policymakers looking to shape public marketplace to ensure that details investments in climate mitigation presented in this report and through agricultural soil carbon credits, accompanying appendix are accurate. protocol developers, project developers This report does not address carbon and aggregators, buyers of credits and accounting outside of published others interested in learning about the protocols meant to generate verified landscape of soil carbon and net carbon credits. greenhouse gas measurement, reporting While not a focus of the report, we and verification protocols. We use the remain concerned that any end-use of term MRV broadly to encompass the carbon credits as an offset, without range of quantification activities, robust local pollution regulations, will structural considerations and perpetuate the historic and ongoing requirements intended to ensure the negative impacts of carbon trading on integrity of quantified credits. disadvantaged communities and Black, This report is based on careful review Indigenous and other communities of and synthesis of publicly available soil color. Carbon markets have enormous organic carbon MRV protocols published potential to incentivize and reward by nonprofit carbon registries and by climate progress, but markets must be private carbon crediting marketplaces. paired with a strong regulatory backing. Acknowledgements This report was supported through a gift Conservation Cropping Protocol; Miguel to Environmental Defense Fund from the Taboada who provided feedback on the High Meadows Foundation for post- FAO GSOC protocol; Radhika Moolgavkar doctoral fellowships and through the at Nori; Robin Rather, Jim Blackburn, Bezos Earth Fund. -
Unique Properties of Water!
Name: _______ANSWER KEY_______________ Class: _____ Date: _______________ Unique Properties of Water! Word Bank: Adhesion Evaporation Polar Surface tension Cohesion Freezing Positive Universal solvent Condensation Melting Sublimation Dissolve Negative 1. The electrons are not shared equally between the hydrogen and oxygen atoms of water creating a Polar molecule. 2. The polarity of water allows it to dissolve most substances. Because of this it is referred to as the universal solvent 3. Water molecules stick to other water molecules. This property is called cohesion. 4. Hydrogen bonds form between adjacent water molecules because the positive charged hydrogen end of one water molecule attracts the negative charged oxygen end of another water molecule. 5. Water molecules stick to other materials due to its polar nature. This property is called adhesion. 6. Hydrogen bonds hold water molecules closely together which causes water to have high surface tension. This is why water tends to clump together to form drops rather than spread out into a thin film. 7. Condensation is when water changes from a gas to a liquid. 8. Sublimation is when water changes from a solid directly to a gas. 9. Freezing is when water changes from a liquid to a solid. 10. Melting is when water changes from a solid to a liquid. 11. Evaporation is when water changes from a liquid to a gas. 12. Why does ice float? Water expands as it freezes, so it is LESS DENSE AS A SOLID. 13. What property refers to water molecules resembling magnets? How are these alike? Polar bonds create positive and negative ends of the molecule. -
Multidisciplinary Design Project Engineering Dictionary Version 0.0.2
Multidisciplinary Design Project Engineering Dictionary Version 0.0.2 February 15, 2006 . DRAFT Cambridge-MIT Institute Multidisciplinary Design Project This Dictionary/Glossary of Engineering terms has been compiled to compliment the work developed as part of the Multi-disciplinary Design Project (MDP), which is a programme to develop teaching material and kits to aid the running of mechtronics projects in Universities and Schools. The project is being carried out with support from the Cambridge-MIT Institute undergraduate teaching programe. For more information about the project please visit the MDP website at http://www-mdp.eng.cam.ac.uk or contact Dr. Peter Long Prof. Alex Slocum Cambridge University Engineering Department Massachusetts Institute of Technology Trumpington Street, 77 Massachusetts Ave. Cambridge. Cambridge MA 02139-4307 CB2 1PZ. USA e-mail: [email protected] e-mail: [email protected] tel: +44 (0) 1223 332779 tel: +1 617 253 0012 For information about the CMI initiative please see Cambridge-MIT Institute website :- http://www.cambridge-mit.org CMI CMI, University of Cambridge Massachusetts Institute of Technology 10 Miller’s Yard, 77 Massachusetts Ave. Mill Lane, Cambridge MA 02139-4307 Cambridge. CB2 1RQ. USA tel: +44 (0) 1223 327207 tel. +1 617 253 7732 fax: +44 (0) 1223 765891 fax. +1 617 258 8539 . DRAFT 2 CMI-MDP Programme 1 Introduction This dictionary/glossary has not been developed as a definative work but as a useful reference book for engi- neering students to search when looking for the meaning of a word/phrase. It has been compiled from a number of existing glossaries together with a number of local additions.