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| Chapter headings and main section headings: Introduction | |
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| Symbolic notation | |
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| Macroscopic Description of Filter Behaviour | |
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| Surface filtration and depth filtration | |
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| Types of filter | |
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| Method of filtration and assessment of efficiency | |
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| Layer efficiency | |
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| Single fibre efficiency | |
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| Filter Structure | |
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| Introduction | |
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| Paper filters | |
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| Carded filters | |
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| Porous foam | |
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| Model filters | |
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| Flow Patterns and Pressure Drop | |
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| Nature of airflow through a filter | |
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| General fluid dynamics theory | |
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| Microscopic airflow patterns in filters | |
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| Filters of irregular or imperfect structure | |
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| Flow in conditions other than simple Stokes flow | |
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| Macroscopic flow patterns | |
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| Flow through filters of non-uniform structure | |
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| Particle Capture by Mechanical Means | |
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| Introduction | |
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| Generalized theory of single fibre efficiency | |
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| Particle capture by direct interception | |
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| Particle capture by inertial impaction | |
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| Capture of particles by gravity | |
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| Capture of particles by diffusional deposition | |
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| Capture of non-spherical particles by fibrous filters | |
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| Combined effect of two or more capture mechanisms | |
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| Variation of deposition site with capture process | |
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| Effect of leakage on filter performance | |
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| Potential problems with model filters | |
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| Electrically Charged Filter Material | |
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| Introduction | |
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| Basic mechanisms of action | |
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| Classification of material | |
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| The importance of electric charge configuration | |
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| Measurement of filter charge | |
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| Charge stability and the effect of storage on filter performance | |
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| Particle Capture by Electric Forces | |
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| Introduction | |
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| Capture by permanently charged fibres | |
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| Capture by image forces | |
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| Experimental observation of electrostatic capture | |
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| Augmentation of filtration efficiency by external electric fields | |
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| Augmentation of filtration efficiency by charging of particles | |
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| Particle Adhesion and Particle Bounce | |
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| Introduction | |
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| Adhesion forces between particles and fibres | |
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| Dynamics of impact | |
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| Effects of Loading | |
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| Introduction | |
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| Qualitative description of filter clogging | |
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| The influence of aerosol properties on clogging rate | |
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| Macroscopic theory of filter clogging | |
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| Airflow pattern and drag force acting on particle complexes | |
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| Theoretical description of clogging | |
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| Experimental observation of dendrite structure on a single fibre | |
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| Experimental observations on model and real fibrous filters | |
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| Fractal structure of particle deposits | |
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| Effect of loading with liquid aerosols | |
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| Time-dependent effects in filter clogging | |
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| The effect of dust loading on the performance of electrically charged filters | |
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| Filter Testing | |
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| Introduction | |
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| Pressure drop measurement | |
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| Area weight measurement | |
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| General problems of aerosol penetration measurement | |
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| Aerosol detectors | |
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| Testing with monodisperse aerosols | |
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| Size-selective testing with polydisperse aerosols | |
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| Non size selective testing with polydisperse aerosols | |
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| Testing of high efficiency filters | |
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| Tests with electrically charged aerosols | |
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| Worst possible case testing | |
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| Realistic prediction of filter performance | |
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| Standard filters | |
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| Conclusion | |
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| Index.150 illus. approx | |