The article “Stability of Silico-Ferrite of Calcium and Aluminum (SFCA) in Air-Solid Solution Limits Between 1240°C and 1390°C and Phase Relationships within the Fe2O3-CaO-Al2O3-SiO2 (FCAS) System” (T. Patrick and M. Pownceby, Metallurgical and Materials Transactions B, 2002:79–90) investigates properties of silico-ferrites of calcium and aluminum (SFCA). The data in the following table present the ratio of the weights of Fe2O3 and CaO for SFCA specimens with several different weight percents of Al2O3 and C4S3.
Al2O3(%) |
C4S3 |
Fe2O3/CaO |
|||
1.0 |
Low (3%-6%) |
7.25 |
6.92 |
6.60 |
6.31 |
1.0 |
Medium (7%-10%) |
6.03 |
5.78 |
5.54 |
5.31 |
1.0 |
High (11%-14%) |
5.10 |
4.90 |
4.71 |
4.53 |
5.0 |
Low (3%-6%) |
6.92 |
6.59 |
6.29 |
6.01 |
5.0 |
Medium (7%-10%) |
5.74 |
5.26 |
5.04 |
4.84 |
5.0 |
High (11%-14%) |
4.84 |
4.65 |
4.47 |
4.29 |
10.0 |
Low (3%-6%) |
6.50 |
6.18 |
5.89 |
5.63 |
10.0 |
Medium (7%-10%) |
5.37 |
5.14 |
4.92 |
4.71 |
10.0 |
High (11%-14%) |
4.52 |
4.33 |
4.16 |
3.99 |
a. Estimate all main effects and interactions.
b. Construct an ANOVA table. You may give ranges for the P-values.
c. Do the data indicate that there are any interactions between the weight percent of Al2O3 and the weight percent of C4S3? Explain.
d. Do the data convincingly demonstrate that the Fe2O3/CaO ratio depends on the weight percent of A12O3? Explain.
e. Do the data convincingly demonstrate that the Fe2O3/CaO ratio depends on the weight percent of C4S3? Explain.
Chapter 2: Measurement 2.1 Significant Figures A. Accuracy and Precision 1) Accuracy: how close a measured value is to _____ the actual value__. 2) Precision: how close measured values are to _each other (average)_ B. Measured numbers • There will be some _uncertainty_ in where to round off a measured quantity based upon the precision of the measuring instrument. • The level of uncertainty is reported by using Significant Figures_ • The _more_ Significant Figures reported, the _more certain_ the measurement. C. Significant Figures (SF) 1 1) A number is Significant if it is: a) Not zero
