A Primer for Sampling Solids, Liquids, and

How does a marble manufacturer know that the color will be consistent throughout the products being made? How can you tell if liquid at the bottom of a container is the same consistency as at the top? How does a pellet manufacturer know if the pellets are consistently the same size? How does a chemical manufacturer know if the percent purity in a sample is representative of the whole batch? These and similar questions are answered in A Primer for Sampling Solids, Liquids, and Gases: Based on the Seven Sampling Errors of Pierre Gy. Author Patricia L. Smith illustrates what to look for in sampling devices and procedures to obtain correct samples from bulk materials. She gives sampling guidelines that can be applied immediately and shows how to analyze protocols to uncover sampling problems.

Preface

xi

Foreword

xv

List of Terms and Symbols

xvii

Some Views of Sampling

1

(6)

The goal of good sampling

1

(1)

Sampling differences

2

(1)

Sampling as scapegoat

2

(1)

A big problem

3

(2)

A structured approach

5

(2)

The Material: Sampling and Material Variation

7

(10)

The nature of heterogeneity

7

(1)

Constitution heterogeneity

8

(1)

Distribution heterogeneity

9

(2)

Quantifying heterogeneity

11

(1)

Reducing the variance of the fundamental error (FE)

12

(1)

Relationship between chemical sample size and statistical sample size

12

(2)

Reducing the grouping and segregation error (GSE)

14

(1)

Summary

15

(2)

The Tools and Techniques: Sampling, Sample Collection, and Sample Handling

17

(20)

Representative sampling

17

(1)

Random sampling

17

(1)

The principle of correct sampling

18

(1)

Grab sampling: A common but poor practice

19

(1)

A crucial determination: The sampling dimension of the lot

20

(6)

Defining and extracting the sample

26

(7)

Sample handling

33

(2)

Summary

35

(2)

The Process: Sampling and Process Variation

37

(18)

Variation over time

37

(1)

Time plots

38

(5)

Time plot summary

43

(1)

The variogram

43

(2)

Intuitive explanation of the variogram

45

(1)

The nugget effect

46

(1)

A caution about irregular sampling or missing samples

47

(2)

Examples

49

(4)

Use of historical data for time plots and variograms

53

(1)

Summary

54

(1)

A Strategy: Putting Theory into Practice

55

(6)

A logical approach

55

(1)

Audit

55

(3)

Assessment

58

(1)

Action

59

(1)

Summary

60

(1)

Appendix A. Introduction to Gy's Seven Sampling Errors

61

(6)

A.1 A structure for sampling

61

(4)

A.2 Grouping used in this primer

65

(2)

Appendix B. The Variance of the Fundamental Error

67

(10)

B.1 Importance

67

(1)

B.2 Heterogeneity of an individual unit

67

(1)

B.3 Theoretical formula for the variance of the fundamental error

68

(1)

B.4 General approximation

69

(1)

B.5 Approximation for particle size distribution

70

(2)

B.6 Other applications

72

(1)

B.7 The effects of particle size reduction (grinding)

72

(2)

B.8 Comparison of measures of variation

74

(3)

Appendix C. Obtaining a Sequential Random Sample

77

(2)

Appendix D. Calculation of the Variogram

79

(6)

Appendix E. Experiments

85

(6)

Appendix F. Sampling Safely

91

(2)

F.1 Introduction

91

(1)

F.2 The material

91

(1)

F.3 The equipment

91

(1)

F.4 The setting

92

(1)

References

93

(2)

Index

95

What is included with this book?

The New copy of this book will include any supplemental materials advertised. Please check the title of the book to determine if it should include any access cards, study guides, lab manuals, CDs, etc.

The Used, Rental and eBook copies of this book are not guaranteed to include any supplemental materials. Typically, only the book itself is included. This is true even if the title states it includes any access cards, study guides, lab manuals, CDs, etc.

FREE SHIPPING

Amazon no longer offers textbook rentals. We do!

A Primer for Sampling Solids, Liquids, and Gases

Summary

Table of Contents

Supplemental Materials