EXTREME PHYSICS UNIT I - NANO-EXPLORATION

 

 

Instructional Goals

 

1.†† Offer empirical observation challenges patterned after real nano-world adventures.

 

††††† In particular, begin with applet-based "virtual-microscope" models that provide geometric information on size scales ranging from macroscopic to atomic, and access to...

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††††† (a) visceral experience with objects ranging in size from millimeters to atoms

††††† (b) real-world characterization problems open to a wide range of problem-solving styles

††††† (c) tasks start with description/estimation of distances, areas, volumes, and shapes...

††††† (d) ...but can extend to molecule recognition, crystal defect analysis, even nano-assembly.

 

††††† In some cases through telepresence, web-mediated access to real live structures on the micron and atomic scale will become possible in the years ahead.

 

2.†† Offer access to diverse and robust forms of data to work with...

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††††† ...including a wide diversity of viewpoints, magnifications, data output formats (e.g. prints, digital images, machine estimates) and calculation tools (e.g. 2D Fourier analysis).In the long run, ability to examine a large number of different:regions (presently limited mainly by memory sizes), signals (e.g. diffraction patterns, x-ray and electron energy spectra, force and I-V curves, secondary and backscattered electron images, etc.) and contrast processes (electron phase contrast, diffraction contrast, darkfield and weak-beam contrast, z-contrast, etc.) will be offered as well.

 

3.†† Work with models that are in practice unknown, and accessible only through a window which involves some experimental uncertainty so that a "literature of discovery" on individual specimens might in fact be developed over time.

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††††† In other words, there is no one right answer or correct way, but only style and resourcefulness and credibility in putting quantitative constraints on what is present in the specimen.As with real world specimens, a literature of discovery (including responsibility for citing previous results) might develop on some of the virtual specimens.

 

4.†† Four use-formats considered:

5.All of the tools (so far at least) can be made available free to web-accessible classrooms

 

††††† One objective here is to let energetic teachers drive content modernization as well as pedagogy, giving book publishers an option to do something they are much better at than modernization, namely following the market.


 

Overview

 

Individual teachers, equipped with materials they and their students can access via the web, are a developing force in the modernization of both pedagogy and content.Although inquiry-based learning is oft considered a method for helping students master facts and algorithms, the perspective from the modern workplace is that empirical discovery and reporting skills in the subject matter of a course deserve to be a goal in themselves.We show here how the nano-frontier provides a robust setting for challenges that put the student in the shoes of real nano-world detectives, and how diverse challenges can be made available on the web by a single "virtual unknown" for students at home, in lecture settings, and even on timed tests.

Our group has provided industry and university researchers across the state with access to new methods, and atom-resolution microscopy capability using both electrons and scanning probes, for over a decade.In addition, weíve also had opportunities to further regional contributions in both materials astronomy (the laboratory study of small but previously stand-alone astrophysical objects) and gigascale integrated circuit silicon manufacturing. These experiences, and our contacts as part of a robust and growing regional nano-characterization alliance, give us insight into characterization tools, methods, applications, and most importantly a large and growing list of past and future challenges.

In this context, the proposed project activities will: (i) expand the list of web-accessible nano-worlds that we presently make available,(ii) develop and deploy storylines suitable for a variety of introductory undergraduate science courses based on real (past, present, or future) characterization challenges along with evaluation rubrics in the form of nano-world WebQuests, and(iii) implement/evaluate the effect of these exercises during two years of introductory classes at UM-StL involving a total of about one thousand students.The goals with respect to participating students are to: (a) increase understanding and ability to gather data, discern patterns, and solve problems posed by real nanoworld studies involving the subject matter of each course;(b) understand and successfully participate in a peer-review of their, and another studentís, report about nano-world observations specific to course subject matter; and(c) enhance awareness of the nano-world, and challenges posed by characterization of matter down to the atomic scale, as it may be encountered in later course work and careers.

Broader Impacts

1. Observation and reporting challenges for courses elsewhere: The materials being developed will be deployed on the web concurrently with their use in our courses, and hence immediately available to web connected classes everywhere.To get the word out, we are talking with regional organizations already (e.g. Saint Louis Area Physics Teachers, American Chemical Society, American Association of Physics Teachers, Central States Microscopy and Microanalysis Society).This project will convert teaching assistants into active meeting participants.It further allows us to follow through on undergraduate education committee interest in teacher workshops at national AAPT meetings, and request by an Am. J. Phys. co-editor for a paper on the strategy.A paper for J. Chem. Ed. may be prepared as well.††

2. Web-based content-modernization generally:It is difficult for text publishers to lead content-modernization, particularly if the courses donít directly address specific career needs of the students taking them.This project generates material for augmenting existing (and two emergent content) classes, and makes it available for use by web-connected teachers worldwide.Given the need for inquiry-based content tied to real-world challenges, it could offer a significant contribution by making figures "come to life" in a variety of intro-science classes.

 

 


Attachments

 

Fleas on Fleas Lab

 

Apparatus

 

††††† The explorer applet

 

Pre-lab discussion

 

Lab performance notes

 

Post-lab discussion

 

Powers of Ten Lab

 

Apparatus

 

††††† The explorer applet

 

Pre-lab discussion

 

 

Lab performance notes

 

 

Post-lab discussion

 

 

 

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