Base course

The problems which the orbital approximation raises in chemical education have been discussed elsewhere by the author (Scerri [1989], [1991]). Briefly, chemistry textbooks often fail to stress the approximate nature of atomic orbitals and imply that the solution to all difficult chemical problems ultimately lies in quantum mechanics. There has been an increassing tendency for chemical education to be biased towards theories, particularly quantum mechanics. Textbooks show a growing tendency to begin with the establishment of theoretical concepts such as atomic orbitals. Only recently has a reaction begun to take place, with a call for more qualitatively based courses and texts (Zuckermann [1986]). A careful consideration of the orbital model would therefore have consequences for chemical education and would clarify the status of various approximate theories purporting to be based on quantum mechanics. 

Teachers should be aware of the learning styles of both themselves and their students, being able to accommodate differences between the two. The use and value of different schemes of work involving context-based courses, demonstration lectures and cooperative learning have been provided by Tsaparlis (2008). 

Thermal property is another critical property for furnace slag. Because of their more porous structure, blast furnace slag aggregates have lower thermal conductivities than conventional aggregates. Their insulating value is of particular advantage in applications such as frost tapers (transition treatments in pavement subgrades between frost-susceptible and nonfrost-susceptible soils) or pavement base courses over frost-susceptible soils. 

Hunsucker DQ (1993) Evaluating the use of ponded fly ash in roadway base course. Symposium proceedings Recovery and Effective Reuse of Discarded Materials and By-products for Construction of Highway Facilities. Federal Highway Administration, FHA 61... 

FIGURE 16.3 Dependences of the polymer retention volume on the logarithm of its molar mass M or hydrodynamic volume log M [T ] (Section 16.2.2). (a) Idealized dependence with a long linear part in absence of enthalpic interactions. Vq is the interstitial volume in the column packed with porous particles, is the total volume of liquid in the column and is the excluded molar mass, (b) log M vs. dependences for the polymer HPLC systems, in which the enthalpic interaction between macromolecules and column packing exceed entropic (exclusion) effects (1-3). Fully retained polymer molar masses are marked with an empty circle. For comparison, the ideal SEC dependence (Figure 16.3a) is shown (4). (c) log M vs. dependences for the polymer HPLC systems, in which the enthalpic interactions are present but the exclusion effects dominate (1), or in which the full (2) or partial (3,4) compensation of enthalpy and entropy appears. For comparison, the ideal SEC dependence (Figure 16.3a) is shown (5). (d) log M vs. dependences for the polymer HPLC systems, in which the enthalpic interactions affect the exclusion based courses. This leads to the enthalpy assisted SEC behavior especially in the vicinity of For comparison, the ideal SEC dependence (Eigure 16.3a) is shown (4). 

Zenieris, P. Lagutos, J. G. 1988. Fly ash as a binder in aggregate base courses. Materials Research Society Svmposinm Proceedings, 113, 231-240. 

There are a number of good choices, but you will not be completely satisfied with any textbook. 1 was not even completely satisfied when 1 used a textbook that I had written. You will probably choose a textbook that is compatible with your sequence of topics. There is at least one popular two-semester textbook that begins with quantum mechanics. (P) Most of the one-volume textbooks begin with thermodynamics but can accommodate different sequences. There are now physical chemistry textbooks that come in two or even four volumes, which provides for flexibility. In making your choice of textbook, you should consider clarity of presentation for the student. Because you are already familiar with die subject, this can be hard for you to judge. I once chose a textbook that seemed perfectly clear to me, but was not at all clear to the students. Next, you should consider the approach of the book. If you want to teach a more mathematically based course, you will probably decide to choose a textbook that uses this approach and not simply plan to provide supplementary information in class. 

Assumed Pavement Parameters. Two typical pavements were selected for this study. One of these consisted of a 2-in. thick surface course on top of an 8-in. thick base course, and the other pavement has a 3-in. thick surface course land over a 10-in. thick base course. These two pavements were assumed to be placed in three different climates whose temperature variations are listed in Table V. 

The subgrade used in the analysis was assumed to be a clay material (A-6 classification) with a moisture content of about 23% and an elastic modulus of 15,000 psi. The base course used in the analysis was assumed to be a dense graded crushed aggregate with an elastic modulus of 60,000 psi. These two materials were assumed to be elastic and are typical of those used in construction of many pavements throughout the U.S. 

No practical details for doing experiments are included, only the results from some typical experiments. Practical work is left to the discretion of the tutors, if this is used as a complete college-based course. This book is intended as a student study guide. 

Pozzolanic Base Course. Compacted pozzolanic materials have the potential for large scale use of fiy ash or modified fiy ash. Compacted base material usually consists of 10-20% fiy ash, 0-10% lime, and the rest aggregate. The mixture is wetted to about 15% moisture for compacting to maximum density. It is then spread and compacted in place. 

The G. W. H. Corson Co. has also used mixtures of fly ash, lime, and sulfate sludge to produce compositions which can be used as paving and as pozzolanic base course. The material is currently being used in the paving demonstration at Dulles International Airport. A portion of the demonstration pavement was made with modified fly ash from the APCS at the Kansas Power and Light, Lawrence Station. 

Base course Subbase course Bituminous stabilization Crusher-run (M-25) New Recycled Recycled... 

Ohio State 40 quarter Internet-based course... 

Smooth wheel rollers, static or Well-graded sand-gravel Running surface, base courses. Uniform sands... 

D.N. Little, Stabilization of Pavement Subgrades and Base Courses with Lime , The National Lime Association, Kendall/Hunt Publishing Co, ISBN 0-8403-9632-5. 

---