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  1. 287441
  2. 287442

    Electron flow in organic chemistry a decision-based guide to organic mechanisms / by Scudder, Paul H.

    Published 2013
    Table of Contents: “…Base Theory 41 2.5 Thermodynamics, Position Of Equilibrium 43 2.6 Kinetics, Rate Of Reaction 47 2.7 Solvent Stabilization Of Ions 53 2.8 Enzymatic Catalysis - Lessons From Biochemistry 55 2.9 Summary 57 3 PROTON TRANSFER AND THE PRINCIPLES OF STABILITY 61 3.1 Introduction To Proton Transfer 62 3.2 Ranking Of Acids And Bases, The pKa Chart 63 3.3 Structural Factors That Influence Acid Strength 66 3.4 Structural Factors That Influence Base Strength 70 3.5 Carbon Acids & Ranking Of Electron-Withdrawing Groups 71 3.6 Calculation Of Keq For Proton Transfer 76 3.7 Proton Transfer Mechanisms 77 3.8 Common Errors 81 3.9 Proton Transfer Product Predictions 82 3.10 Summary 83 4 IMPORTANT REACTION ARCHETYPES 88 4.1 Introduction To Reaction Archetypes 89 4.2 Nucleophilic Substitution At A Tetrahedral Center 89 4.3 Elimination Reactions Create Pi Bonds 110 4.4 Addition Reactions To Polarized Multiple Bonds 124 4.5 Nucleophilic Substitution At A Trigonal Planar Center 133 4.6 Electrophilic Substitution At A Trigonal Planar Center 140 4.7 Rearrangements To An Electrophilic Carbon 144 4.8 Reaction Archetype Summary 146 5 CLASSIFICATION OF ELECTRON SOURCES 151 5.1 Generalized Ranking Of Electron Sources 151 5.2 Nonbonding Electrons 152 5.3 Electron-Rich Sigma Bonds 154 5.4 Electron-Rich Pi Bonds 155 5.5 Simple Pi Bonds 156 5.6 Aromatic Rings 159 5.7 Summary Of Generic Electron Sources 160 6 CLASSIFICATION OF ELECTRON SINKS 166 6.1 Generalized Ranking Of Electron Sinks 166 6.2 Electron-Deficient Species 167 6.3 Weak Single Bonds 168 6.4 Polarized Multiple Bonds Without Leaving Groups 170 6.5 Polarized Multiple Bonds With Leaving Groups 172 6.6 Summary Of Generic Electron Sinks 173 7 THE ELECTRON FLOW PATHWAYS 179 7.1 The Dozen Most Common Pathways 180 7.2 Six Minor Pathways 191 7.3 Common Path Combinations 197 7.4 Variations On A Theme 201 7.5 Twelve Major Paths Summary And Crosschecks 208 8 INTERACTION OF ELECTRON SOURCES AND SINKS 213 8.1 Source And Sink Correlation Matrix 214 8.2 H-A Sinks Reacting With Common Sources 214 8.3 Y?…”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  3. 287443

    Enhancing Collaboration in Online Learning by Munyao, Martin, Wachirah, Serah

    Published 2023
    “…Online Learning, Instruction, and Research in Post-Pandemic Higher Education in Africa, edited by Martin Munyao, argues that beyond survival, universities need to adapt to technology-mediated communication learning in order to thrive. …”
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    Book chapter
  4. 287444

    Kenyans are Still Oppressed by Archaic Colonial Laws by Muendo, Mercy

    Published 2023
    “…These laws were inherited from the colonial British government and used to be within the purview oflocal government municipalities under the Local Government Act . This act was repealed whenmunicipalities were replaced by counties after the promulgation of the 2010 Constitution .…”
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    Article
  5. 287445

    E-learning and the science of instruction proven guidelines for consumers and designers of multimedia learning / by Clark, Ruth Colvin

    Published 2011
    Table of Contents: “…Applying the Segmenting and Pretraining Principles: Managing Complexity by Breaking a Lesson into Parts.Segmenting Principle: Break a Continuous Lesson into Bite-Size Segments.Psychological Reasons for the Segmenting Principle.Evidence for Breaking a Continuous Lesson into Bite-Size Segments.Pretraining Principle: Ensure That Learners Know the Names and Characteristics of Key Concepts.Psychological Reasons for the Pretraining Principle.Evidence for Providing Pretraining in Key Concepts.What We Don't Know About Segmenting and Pretraining.11. …”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  6. 287446

    Statistical disclosure control

    Published 2012
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  7. 287447

    Efficient preparations of fluorine compounds

    Published 2013
    Table of Contents: “…Lozano 63 Dehydroxyfluorinations of Primary or Secondary Alcohols Using Perfluoro n-butylsulfonyl Fluoride (nonaflyl Fluoride, NfF) in Combination with 1,8-Diaza-bicyclo[5.4.0]undec-7-ene (DBU) Orlin Petrov, Matthias Schneider, Rolf Bohlmann, Stephan Vettel, Helmut Vorbruggen 64 Preparation of Rare Earth Fluorosulfides and Oxyfluorosulfides A. Demourgues, A.Tressaud 65 Preparation of Carbon-Fluorine Compounds and Fluoride or Oxide Fluoride-Intercalated Graphites Tsuyoshi Nakajima 66 Safe Synthesis of Superstoichiometric Mesoporous Fluorocarbons Valentin N. …”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  8. 287448

    Fatigue of materials and structures application to design and damage /

    Published 2011
    Table of Contents: “…Superposition" method -- 3.4.5.Superposition method: applicable examples -- 3.4.6.Numerical application exercise -- 3.5.Performing some "damage tolerance" calculations -- 3.5.1.Complementarity of fatigue and damage tolerance -- 3.5.2.Safety coefficients to understand curve a = f(N) -- 3.5.3.Acquisition of the material parameters -- 3.5.4.Negative parameter: corrosion -- "corrosion fatigue" -- 3.6.Application to the residual strength of thin sheets -- 3.6.1.Planar panels: Feddersen diagram -- 3.6.2.Case of stiffened panels -- 3.7.Propagation of cracks subjected to random loading in the aeronautic industry -- 3.7.1.Modeling of the interactions of loading cycles -- 3.7.2.Comparison of predictions with experimental results -- 3.7.3.Rainflow treatment of random loadings -- 3.8.Conclusion -- 3.8.1.Organization of the evolution of "damage tolerance" -- 3.8.2.Structural maintenance program -- 3.8.3.Inspection of structures being used -- 3.9.Damage tolerance within the gigacyclic domain -- 3.9.1.Observations on crack propagation -- 3.9.2.Propagation of a fish-eye with regards to damage tolerance -- 3.9.3.Example of a turbine disk subjected to vibration -- 3.10.Bibliography -- ch. 4 Defect Influence on the Fatigue Behavior of Metallic Materials / Gilles Baudry -- 4.1.Introduction -- 4.2.Some facts -- 4.2.1.Failure observation -- 4.2.2.Endurance limit level -- 4.2.3.Influence of the rolling reduction ratio and the effect of rolling direction -- 4.2.4.Low cycle fatigue: SN curves -- 4.2.5.Wohler curve: existence of an endurance limit -- 4.2.6.Summary -- 4.3.Approaches -- 4.3.1.First models -- 4.3.2.Kitagawa diagram -- 4.3.3.Murakami model -- 4.4.A few examples -- 4.4.1.Medium-loaded components: example of as-forged parts: connecting rods -- effect of the forging skin -- 4.4.2.High-loaded components: relative importance of cleanliness and surface state -- example of the valve spring -- 4.4.3.High-loaded components: Bearings-Endurance cleanliness relationship -- 4.5.Prospects -- 4.5.1.Estimation of lifetimes and their dispersions -- 4.5.2.Fiber orientation -- 4.5.3.Prestressing -- 4.5.4.Corrosion -- 4.5.5.Complex loadings: spectra/over-loadings/multiaxial loadings -- 4.5.6.Gigacycle fatigue -- 4.6.Conclusion -- 4.7.Bibliography -- ch. 5 Fretting Fatigue: Modeling and Applications / Trevor Lindley -- 5.1.Introduction -- 5.2.Experimental methods -- 5.2.1.Fatigue specimens and contact pads -- 5.2.2.Fatigue S-N data with and without fretting -- 5.2.3.Frictional force measurement -- 5.2.4.Metallography and fractography -- 5.2.5.Mechanisms in fretting fatigue -- 5.3.Fretting fatigue analysis -- 5.3.1.The S-N approach -- 5.3.2.Fretting modeling -- 5.3.3.Two-body contact -- 5.3.4.Fatigue crack initiation -- 5.3.5.Analysis of cracks: the fracture mechanics approach -- 5.3.6.Propagation -- 5.4.Applications under fretting conditions -- 5.4.1.Metallic material: partial slip regime -- 5.4.2.Epoxy polymers: development of cracks under a total slip regime -- 5.5.Palliatives to combat fretting fatigue -- 5.6.Conclusions -- 5.7.Bibliography -- ch. 6 Contact Fatigue / Ky Dang Van -- 6.1.Introduction -- 6.2.Classification of the main types of contact damage -- 6.2.1.Background -- 6.2.2.Damage induced by rolling contacts with or without sliding effect -- 6.2.3.Fretting -- 6.3.A few results on contact mechanics -- 6.3.1.Hertz solution -- 6.3.2.Case of contact with friction under total sliding conditions -- 6.3.3.Case of contact with partial sliding -- 6.3.4.Elastic contact between two solids of different elastic modules -- 6.3.5.3D elastic contact -- 6.4.Elastic limit -- 6.5.Elastoplastic contact -- 6.5.1.Stationary methods -- 6.5.2.Direct cyclic method -- 6.6.Application to modeling of a few contact fatigue issues -- 6.6.1.General methodology -- 6.6.2.Initiation of fatigue cracks in rails -- 6.6.3.Propagation of initiated cracks -- 6.6.4.Application to fretting fatigue -- 6.7.Conclusion -- 6.8.Bibliography -- ch. 7 Thermal Fatigue / Luc Remy -- 7.1.Introduction -- 7.2.Characterization tests -- 7.2.1.Cyclic mechanical behavior -- 7.2.2.Damage -- 7.3.Constitutive and damage models at variable temperatures -- 7.3.1.Constitutive laws -- 7.3.2.Damage process modeling based on fatigue conditions -- 7.3.3.Modeling the damage process in complex cases: towards considering interactions with creep and oxidation phenomena -- 7.4.Applications -- 7.4.1.Exhaust manifolds in automotive industry -- 7.4.2.Cylinder heads made from aluminum alloys in the automotive industry -- 7.4.3.Brake disks in the rail and automotive industries -- 7.4.4.Nuclear industry pipes -- 7.4.5.Simple structures simulating turbine blades -- 7.5.Conclusion -- 7.6.Bibliography.…”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  9. 287449

    E-learning and the science of instruction proven guidelines for consumers and designers of multimedia learning / by Clark, Ruth Colvin

    Published 2011
    Table of Contents: “…Applying the Segmenting and Pretraining Principles: Managing Complexity by Breaking a Lesson into Parts.Segmenting Principle: Break a Continuous Lesson into Bite-Size Segments.Psychological Reasons for the Segmenting Principle.Evidence for Breaking a Continuous Lesson into Bite-Size Segments.Pretraining Principle: Ensure That Learners Know the Names and Characteristics of Key Concepts.Psychological Reasons for the Pretraining Principle.Evidence for Providing Pretraining in Key Concepts.What We Don't Know About Segmenting and Pretraining.11. …”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  10. 287450

    Statistical disclosure control

    Published 2012
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  11. 287451

    Efficient preparations of fluorine compounds

    Published 2013
    Table of Contents: “…Lozano 63 Dehydroxyfluorinations of Primary or Secondary Alcohols Using Perfluoro n-butylsulfonyl Fluoride (nonaflyl Fluoride, NfF) in Combination with 1,8-Diaza-bicyclo[5.4.0]undec-7-ene (DBU) Orlin Petrov, Matthias Schneider, Rolf Bohlmann, Stephan Vettel, Helmut Vorbruggen 64 Preparation of Rare Earth Fluorosulfides and Oxyfluorosulfides A. Demourgues, A.Tressaud 65 Preparation of Carbon-Fluorine Compounds and Fluoride or Oxide Fluoride-Intercalated Graphites Tsuyoshi Nakajima 66 Safe Synthesis of Superstoichiometric Mesoporous Fluorocarbons Valentin N. …”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  12. 287452

    Fatigue of materials and structures application to design and damage /

    Published 2011
    Table of Contents: “…Superposition" method -- 3.4.5.Superposition method: applicable examples -- 3.4.6.Numerical application exercise -- 3.5.Performing some "damage tolerance" calculations -- 3.5.1.Complementarity of fatigue and damage tolerance -- 3.5.2.Safety coefficients to understand curve a = f(N) -- 3.5.3.Acquisition of the material parameters -- 3.5.4.Negative parameter: corrosion -- "corrosion fatigue" -- 3.6.Application to the residual strength of thin sheets -- 3.6.1.Planar panels: Feddersen diagram -- 3.6.2.Case of stiffened panels -- 3.7.Propagation of cracks subjected to random loading in the aeronautic industry -- 3.7.1.Modeling of the interactions of loading cycles -- 3.7.2.Comparison of predictions with experimental results -- 3.7.3.Rainflow treatment of random loadings -- 3.8.Conclusion -- 3.8.1.Organization of the evolution of "damage tolerance" -- 3.8.2.Structural maintenance program -- 3.8.3.Inspection of structures being used -- 3.9.Damage tolerance within the gigacyclic domain -- 3.9.1.Observations on crack propagation -- 3.9.2.Propagation of a fish-eye with regards to damage tolerance -- 3.9.3.Example of a turbine disk subjected to vibration -- 3.10.Bibliography -- ch. 4 Defect Influence on the Fatigue Behavior of Metallic Materials / Gilles Baudry -- 4.1.Introduction -- 4.2.Some facts -- 4.2.1.Failure observation -- 4.2.2.Endurance limit level -- 4.2.3.Influence of the rolling reduction ratio and the effect of rolling direction -- 4.2.4.Low cycle fatigue: SN curves -- 4.2.5.Wohler curve: existence of an endurance limit -- 4.2.6.Summary -- 4.3.Approaches -- 4.3.1.First models -- 4.3.2.Kitagawa diagram -- 4.3.3.Murakami model -- 4.4.A few examples -- 4.4.1.Medium-loaded components: example of as-forged parts: connecting rods -- effect of the forging skin -- 4.4.2.High-loaded components: relative importance of cleanliness and surface state -- example of the valve spring -- 4.4.3.High-loaded components: Bearings-Endurance cleanliness relationship -- 4.5.Prospects -- 4.5.1.Estimation of lifetimes and their dispersions -- 4.5.2.Fiber orientation -- 4.5.3.Prestressing -- 4.5.4.Corrosion -- 4.5.5.Complex loadings: spectra/over-loadings/multiaxial loadings -- 4.5.6.Gigacycle fatigue -- 4.6.Conclusion -- 4.7.Bibliography -- ch. 5 Fretting Fatigue: Modeling and Applications / Trevor Lindley -- 5.1.Introduction -- 5.2.Experimental methods -- 5.2.1.Fatigue specimens and contact pads -- 5.2.2.Fatigue S-N data with and without fretting -- 5.2.3.Frictional force measurement -- 5.2.4.Metallography and fractography -- 5.2.5.Mechanisms in fretting fatigue -- 5.3.Fretting fatigue analysis -- 5.3.1.The S-N approach -- 5.3.2.Fretting modeling -- 5.3.3.Two-body contact -- 5.3.4.Fatigue crack initiation -- 5.3.5.Analysis of cracks: the fracture mechanics approach -- 5.3.6.Propagation -- 5.4.Applications under fretting conditions -- 5.4.1.Metallic material: partial slip regime -- 5.4.2.Epoxy polymers: development of cracks under a total slip regime -- 5.5.Palliatives to combat fretting fatigue -- 5.6.Conclusions -- 5.7.Bibliography -- ch. 6 Contact Fatigue / Ky Dang Van -- 6.1.Introduction -- 6.2.Classification of the main types of contact damage -- 6.2.1.Background -- 6.2.2.Damage induced by rolling contacts with or without sliding effect -- 6.2.3.Fretting -- 6.3.A few results on contact mechanics -- 6.3.1.Hertz solution -- 6.3.2.Case of contact with friction under total sliding conditions -- 6.3.3.Case of contact with partial sliding -- 6.3.4.Elastic contact between two solids of different elastic modules -- 6.3.5.3D elastic contact -- 6.4.Elastic limit -- 6.5.Elastoplastic contact -- 6.5.1.Stationary methods -- 6.5.2.Direct cyclic method -- 6.6.Application to modeling of a few contact fatigue issues -- 6.6.1.General methodology -- 6.6.2.Initiation of fatigue cracks in rails -- 6.6.3.Propagation of initiated cracks -- 6.6.4.Application to fretting fatigue -- 6.7.Conclusion -- 6.8.Bibliography -- ch. 7 Thermal Fatigue / Luc Remy -- 7.1.Introduction -- 7.2.Characterization tests -- 7.2.1.Cyclic mechanical behavior -- 7.2.2.Damage -- 7.3.Constitutive and damage models at variable temperatures -- 7.3.1.Constitutive laws -- 7.3.2.Damage process modeling based on fatigue conditions -- 7.3.3.Modeling the damage process in complex cases: towards considering interactions with creep and oxidation phenomena -- 7.4.Applications -- 7.4.1.Exhaust manifolds in automotive industry -- 7.4.2.Cylinder heads made from aluminum alloys in the automotive industry -- 7.4.3.Brake disks in the rail and automotive industries -- 7.4.4.Nuclear industry pipes -- 7.4.5.Simple structures simulating turbine blades -- 7.5.Conclusion -- 7.6.Bibliography.…”
    An electronic book accessible through the World Wide Web; click to view
    Electronic eBook
  13. 287453

    Eroding local capacity : international humanitarian action in africa.

    Published 2002
    Book
  14. 287454

    Eroding local capacity : international humanitarian action in africa.

    Published 2002
    Book
  15. 287455
  16. 287456
  17. 287457

    The Use of Electronic Tracking and Monitoring Systems and the Right to Privacy by Moni, Wekesa, Muendo, Mercy, Mikinyango, Asha

    Published 2023
    “…On the other side Governments have employed electronic monitoring and tracking techniques as part of their security tool kit. The employment of electronic monitoring has an impact on the individual’s right to privacy. …”
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    Article
  18. 287458

    Developing a Framework for Promoting Blended Learning (Teachnology) among Communication Students at Daystar University by Kowuor, Rosemary Nyaole

    Published 2021
    “…This implies that my data analysis was part of data gathering. It was a continuous process, as we reflected on learning activities during previous classes; adopted instructional practices that promoted reflective learning and discarded those that inhibited reflective learning. …”
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    Other
  19. 287459
  20. 287460