T e Gatan MonoCL uses a mirror arrangement to direct the light to the optics. It may be that the longer wavelengths (red-orange) need a diff erent geometry for optimization of the collection. I would try and move the sample height and see if the spectra sensitivity changes with respect to the red end of the spectrum. T e MonoCl systems typically have a PMT detector to detect the light, and these usually have adjustable gain. Since the longer wavelengths are energetically weak, you may have to increase the gain to detect these less energetic wavelengths. Colin MacRae Mon Nov 20 I believe Colin is correct about fi nding the right focal point with the GatanCL. We also have this detector on a Hitachi 3400 and have no problems with the red signal. However, fi nding the right focal point can be essential. 0.5 mm adjustment in the Z axis or less can make a big diff erence in signal strength. Phil Oshel Mon Nov 20

EDS and SEM: project for outreach

My company runs a community outreach program for local elementary school students (8-10 years old). T ey tour our facility and see quick demonstrations/lectures on a variety of topics. We have had an SEM demo for years, and I would like to incorporate our EDS, but I’m having trouble coming up with samples that kids that age understand, especially since I only have 15 minutes per group and we try to go through at least four samples. I have generated a map of diff erent elements in a vitamin tablet which went over well and gives them a good understanding of what the system is doing. Any recommendations for samples that generate interesting maps or have unexpected elements? I’ll be doing the prep/high quality maps ahead of time so that doesn’t need to be done in the 15 minutes. I’d also like to get a wireless projector to use with our Hitachi SU3500 to project a live image of the screen onto the wall. Our service rep said some models could cause driver issues so if anyone here has a model that works, please let me know. We need to stay under US$500, but under $300 would be ideal. Annie Muske-Dukes Fri Nov 17 I’ve had good results showing young people fossils, shells or dinosaur bone fragments. Kids love those! Also, teeth and hair can be interesting. Hair is especially captivating because they can donate it from their head and it becomes personal. It also contains S which is a surprise to most people. Zack Gainsforth Sat Nov 18 It is always fun to present science to young minds! I would suggest table salt. Nice crystal structure for morphology and an easy spectrum. I’ve also done a comparison with table salt and natural salts (Sea or Himalayan) which can show diff erences in both morphology and spectra. Gene Rodek Mon Nov 20 I once used a nice paper towel with Christmas decorations, gold, silver and black patterns on the blue towel. It is particularly stiff and looks very close to a real woven towel. So I kept one for SEM practicals with students. You should be able to fi nd something similar. I didn’t try it with young children, but I imagine it could do the job. T ey can have the towel in their hands, and see in Se/BSe a synthetic/cellulose fi ber network, in BSe a compositional contrast image, and by EDS in spectrum mode showing that the “gold” is brass, the “silver” is aluminum, and the black is carb. All that shines is not gold. Jacques Faerber Mon Nov 20 Teeth, rocks (granite). Kleo Pullin

Mon Nov 20

I usually show coins and matches (new and burnt) for similar purpose. Coins for oxidation (Copper coin) and metal allergies (Ni alloy). Matches produce nice elemental maps of Cl, K, Na. Elio sem. Mon Nov 20

2018 March •

I usually deal with kids in the 12 - 18 YO range for outreach. In

the past, we off ered a week-long half-day experience in the lab. In my experience, it is critical to fi nd samples that kids can relate to. Insects can be a good for imaging. My favorites are honey bees, house fl ies and fruit fl ies. Kids like the structure of the eye. Epsom salt has a nice structure and is useful for EDX; however, it can take a long time to get vacuum since it is usually hydrated. Best to only use a few crystals or pre-pump. Geological samples. I prefer a thin section to reduce pump time, but bulk sections work too. If you need a thin section, I suspect Spectrum Petrographics could help. I have no fi nancial connection to them, but I know several of our geology Professors have Spectrum do their mounts. I had one student bring hair and feathers from the farm she lives on. T ere is a signifi cant diff erence between animals. House hold dust can be a good sample. Just pick a spot like a window sill and don’t clean it for a week or two. Collect the sample with C tape on a stub. I have seen pollen, insect parts and silicate minerals. Greg Baty Mon Nov 20

I did a CSI type demo using light bulb fi laments. T e scenario was that there was a traffi c accident in the dark and each driver claimed the others headlights were not on. T e headlamps in both cars were broken. T e 2nd driver claims that the 1st driver turned on his headlights aſt er the bulbs were broken in order to cover his fault. T e offi cer collected the light bulb fi laments from the cars, and you are comparing them in the SEM. (You can spin out the story as much as you want!) I took 2 small incandescent bulbs (15 watt if I remember), broke the glass on one and then applied power so that it burned out. I took the 2nd and broke the glass while it was running. I then mounted the 2 fi laments on an SEM sticky tab and put them in the scope. Note: be careful about breaking the glass. Do it safely! I wore safety glasses and leather gloves and used a pair of channel pliers to hold the bulb inside a mostly closed cardboard box to contain the glass fragments. On examination, the student will fi nd small spherical globs on one fi lament and none on the other. Doing EDX shows that the spherical globs are Si and O (i.e. glass that melted). T e inference is that the fi lament was hot when the glass was broken, hence the light bulb was on. T e other bulb is just oxidized and doesn’t show any melted glass. Hence it was not running when the glass broke and was burned out aſt erwards. T ey seemed to enjoy the “real life” problem solving. Henk Colijn Tue Nov 21 T ank you so much for this question. I am always in need of good ideas. We usually have a Solve the Mystery in the Family Aff air, which is changing its name this year to Microscopic Explorations, for the delegates’ families and friends at the M&M conference. T e pattern has developed whereby in a session on the Wednesday aſt ernoon, it typically starts with an introduction and then a lot of hands on activities using loupes and light microscopes adapted from the GEMS Microscopical Explorations activities. At least three of the stations have a “solve the mystery.” At the next meeting in Baltimore, we are developing one step further, and we hope to have Fold scopes and micro meteorites. T en the participants go to the vendor hall where we usually have access to four SEMs to “Solve the Mystery”. I have tried to correlate the mystery with the place and change it each year. For instance, the CSI Albuquerque story was: T e Governor of New Mexico is coming to town. He is a baseball fan, and his favorite team is the Albuquerque Isotopes. He was going to have his photograph taken with the cup the Isotopes just won! But disaster struck! Someone stole the cup! It is very important we get the cup back. We have to fi nd out who did it. T e thief leſt several clues at the scene of the crime: • Some pollen • Some hair • Some sand • Some fi bers


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76