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here, a list of some image sources we found for you. |
if you know any other good ones, please share them with us in the arena “tagging” Miri Esther, our responsible for keeping this list up-to-date! |
> the commons (on flickr): from the world’s public photography archives. |
> retronaut’s time capsules: see the past like you wouldn’t believe. |
> the new york public library: digitalized original images from books, magazines and newspapers, mostly created before 1923. |
> medieval and renaissance material culture: occupations, clothing, animals, tools, utensils, games, pastimes, crime, punishment… from the middle ages + renaissance! |
> google art project: artworks, high-res + walk-through museums feature! |
> world wonders project: explore historic sites as if you were there. |
> historic moments: stories behind significant moments in human history. |
> pixabay.com: free high res images, free videos as well! |
> morguefile.com: high res stock photos by creatives for creatives! |
> foter.com: free for non commercial use. “buildings” section is great. |
> everystockphoto.com: a serch engine for free images or wirth a specific licence. |
> im creator: some free, some not, but worth it! |
#arc1o1exhibition goes to ural industrial biennial of contemporary art! |
curator yana novoslugina for welcoming our matchboxes in such a beautifully curated way. |
another very special thank you to our crew member dina neri for organizing the collaboration with okno gallery. |
Comments Off on #arc1o1exhibition goes to ural industrial biennial of contemporary art! |
we publish some as well! |
in collages we really trust! |
you like to write ? |
Traditionally, quantum theory has been viewed as a "difficult" topic, mainly because of the symbolic-mathematical content. For example, Francl notes that two semesters of calculus is usually required for physical chemistry (1), and this is certainly true for quantum theory. The traditional approach emphases the use of ... |
Interestingly, the last 20-30 years has witnessed a paradigm shift in the practice of quantum chemistry. Leading up to the 1970s, quantum chemistry was monopolized by theoretical chemists, who were as much mathematicians as chemists. One had to be conversant with the mathematical methodology in order to perform a quant... |
The "new calculus" in mathematics education (eg, 2) advocates the "rule of four" (numerical, graphical, symbolic and verbal descriptions) to deepen students' conceptual understanding (eg, 3). This "new calculus" acknowledges that a predominantly symbolic approach to mathematics is suitable for some, but not all, studen... |
This paper describes the use of spreadsheets to generate approximate numerical solutions and visual (graphical) descriptions as a method of avoiding or minimizing symbolic manipulations, mathematical derivations and numerical computation. The aim here is to teach the qualitative results that arise from quantum theory, ... |
Electrons (and atoms?) exhibit both wave-like and particle-like behavior. |
Students are usually first introduced to quantum theory through the wavefunctions for the 1-dimensional Schrödinger equation. Exact solutions are derived for the particle-in-a-box (the Kuhn model (4)) and the simple harmonic oscillator model. The shapes of the potentials for these models are shown in Figure 1. |
Figure 1. Potential functions for the particle-in-a-box model (left) and the simple harmonic oscillator model (right). |
where Hn(x) is the Hermite polynomial of order n. The novice learner sees the differences between Equation 1 and Equation 2 and concludes that every potential is treated as a special case! |
Potentials such has the triangular and stepped-valley models, shown in Figure 2, have no closed-form (ie analytic) wavefunction solutions. Similarly, the quantized energies cannot be given by any analytic equation. Here, the novice learner concludes incorrectly either that quantum mechanics does not apply, or that many... |
Figure 2. Simple piecewise-continuous potential functions for which the wavefunction does not have any closed form: a triangular potential (left) and a stepped-valley potential (right). |
In p-chem classes at Deakin University, the derivative is explained as the "slope of a function". The 2nd order differential Schrödinger equation for an electron-in-a-box (the Kuhn model (4)) is explained as "finding the slope of a slope". The 1st order Euler method for generating numerical solutions is explained. No c... |
Figure 3. Approximate trial wavefunctions for the triangular potential (Figure 2), arranged from high energy (top) to low energy (bottom). Shaded domains are the forbidden region: V(x) < E. |
Students discover that energy determines the wavelength of the wavefunction, and that valid solutions require that only special ("allowed") wavelengths will fit the dimension of the potential (Figure 3). It is observed that, as wavelength decreases, the number of nodes (the zeroes or roots of the wavefunction) increase... |
For example, the molecular orbitals for cyclopentadienyl have, in increasing order of energy, no nodes, one node and two nodes respectively (Figure 4). Similarly, the rotational wavefunctions can be generated by considering nodal patterns on the surface of a sphere. Much of Schrödinger's original work was based on Hami... |
Figure 4. molecular orbitals for cyclopentadienyl. Shading of the circles in the centre panels represent the sign (direction) of the pz orbitals. The pzorbitals change sign across nodal planes, which are shown as blue lines. |
On further exploration with the spreadsheet quantum_well.xls, students discover that the shapes of the allowed one-dimensional wavefunctions are similar (Figure 5), even for different potential models: ie, the lowest-energy wavefunctions all have one "bump", with no nodes. |
Figure 5. Lowest-energy approximate wavefunctions for the particle-in-a-box (top panel), simple harmonic oscillator (2nd panel), triangular (3rd panel) and stepped-valley (bottom panel) potentials of Figure 1 andFigure 2. Shaded domains are the forbidden region: V(x) < E. |
the use of a series of square wells separated by barriers (extended Kronig-Penney model) illustrates that interactions between wells split energy levels. As the number of wells increases, the (single-well) energy splits into a quasi-continuous band of energies, giving rise to the band theory for conductors and semi-con... |
Although there has been a substantial history in the use of spreadsheet and graphical applications in education (eg 9,10), the author believes that full utilization of the technology, especially in chemical education, has not been realized. |
The aim of this paper is to teach the qualitative results that arise from applying mathematics to physical and chemical systems, but without the mathematical rigor: "teaching maths with minimal maths". The "new calculus" advocates the "rule of four" (numerical, graphical, symbolic and verbal descriptions) to deepen stu... |
The Logical-Mathematical intelligence is only one of multiple "intelligences" (11). By changing the emphasis away from mathematical calculus, the numerical-experimental activity, can also cater to those students who favor Spatial or Bodily-Kinesthetic intelligences. A combination of this spreadsheet approach with the t... |
This paper has focused on the use of spreadsheets but, in principle, the simulations can be done using symbolic mathematical packages such as Mathematica, Maple or MathCAD. This would only be feasible for students who already have a strong mathematical background. This author prefers the use of spreadsheets for weaker ... |
While weaker students will use the spreadsheets, discussed in this paper, as "black boxes", more able students can construct similar, appropriate spreadsheets (eg17-19). Instructors will need to be careful in deciding to use the "black box" approach or to require students construct their own. If successfully completed,... |
The key feature of using spreadsheets is that students do "numerical experiments". (There is an interesting discussion of the use of numerical experiments in (20-22). Numerical experiments (eg 23) were also a key part of the development of chaos theory (20).) By playing with "what-if" scenarios, students can test the v... |
This paper is an expanded version of case studies to be published by LTSN Maths, Stats & OR Network <http://ltsn.mathstore.ac.uk/mathsteam> and by LTSN Physical Sciences <http://www.physsci.ltsn.ac.uk>. |
KFL thanks Ms Jeanne Lee ( ) (Australian Catholic University) for encouraging and helpful discussions, Dr Paul Yates<http://www.keele.ac.uk/depts/ch/staff/pcy/pcy.html> (Keele University, UK) for suggestions to improve the spreadsheet quantum_well.xls, and Associate Professor (Emeritus) Ian Johnston <http://www.physics... |
All URLs checked on 7 March 2003. |
Francl, M., Survival Guide for Physical Chemistry; Physics Curriculum and Instruction: Lakeville (MN), 2001. |
Preparing for a New Calculus; Solow, A. E., ed. Mathematical Association of America: Washington (DC), 1994; Vol. 36. |
Stewart, J., "Introduction" in Calculus; 4th Ed.; Brooks/Cole: Pacific Grove (CA), 1999. |
Kuhn, H., "A quantum-mechanics theory of light absorption of organic dyes and similar compounds", J. Chem. Phys. 1949, 17, 1198. |
Levine, I. N., Quantum Chemistry; 5th Ed.; Prentice Hall: Upper Saddle River (NJ), 2000. |
Press, A. H.; Teukolsky, S. A.; Vetterling, W. T.; Flannery, B. P., Numerical Recipes in Fortran 77: The Art of Scientific Computing; 2nd Ed.; Cambridge University Press: New York, 1996; Vol. 1. |
de Bono, E., Lateral Thinking: A textbook of creativity; Penguin: London, 1990. |
McMurry, J., Organic Chemistry; 5th Ed.; Brooks/Cole: Pacific Grove (CA), 2000. |
Bridges, R., "Graphical spreadsheets", Mathematics in Schools 1991, 20, 2. |
Wood, J., "Utilizing the spreadsheet and charting capabilities of Microsoft Works in the the mathematics classroom", Journal of Computers in Mathematics and Science Teaching 1990, 9, 65. |
Gardner, H., Frames of Mind: The Theory of Multiple Intelligences; 2nd Ed.; Fontana: London, 1993. |
Galbraith, P.; Pemberton, M., "Convergence or divergence? Students, Maple, and mathematics learning", in Mathematics Education in the South Pacific; B. Barton, K. C. Irwin, M. Pfannkuch and M. O. J. Thomas, eds.; Mathematics Education Research Group of Australasia: Pymble (NSW), 2002; Vol. 1; p 285. |
Ehrmann, S. C., "Asking the right question: What does research tell us about technology and higher learning?" Change: The Magazine of Higher Learning1995, 27 (2), 20 <http://www.learner.org/edtech/rscheval/rightquestion.html>. |
[supplementary material: Journal of Chemical Education: Webware, paper WW003 <http://jchemed.chem.wisc.edu/JCEWWW/Features/WebWare/WW003/index.html>]. |
Maddux, C. D.; Johnson, D. L.; Willis, J. W., Educational Computing: Learning with tomorrow's technologies; Allyn and Bacon: Needham Heights (MA), 1997. |
Miles, D. G., Jr.; Francis, T. A., "A survey of computer use in undergraduate physical chemistry", J. Chem. Educ. 2002, 79, 1477 <http://jchemed.chem.wisc.edu/Journal/Issues/2002/Dec/abs1477.html>. |
de Levie, R., How to Use Excel in Analytical Chemistry and in General Scientific Data Analysis; Cambridge University Press: Cambridge (UK), 1999. |
Diamond, D.; Hanratty, V. C. A., Spreadsheet Applications in Chemistry Using Microsoft Excel; Wiley: New York, 1997. |
Kaess, M.; Easter, J.; Cohn, K., "Visual Basic and Excel in chemical modeling", J. Chem. Educ. 1998, 75, 642 <http://jchemed.chem.wisc.edu/Journal/Issues/1998/May/abs642.html>. |
Gleick, J., Chaos; Viking: New York, 1987. |
Redish, E. F.; Wilson, J. M., "Student programming in the introductory physics course: M.U.P.P.E.T." Am. J. Phys. 1993, 61, 222 <http://www2.physics.umd.edu/~redish/Papers/mupajp.html>. |
Redish, E. F., University of Maryland, Published papers describing M.U.P.P.E.T. <http://www.physics.umd.edu/ripe/muppet/papers.html>, 1995 (accessed 20 December 2001). |
Hénon, M.; Heiles, C., "The applicability of the third integral of motion: some numerical experiments", Astron. J. 1964, 69, 73. |
Bee, H. L., The Developing Child; 8th Ed.; Longman: New York, 1997. |
McInerney, D. M.; McInerney, V., Educational Psychology: Constructing knowledge; 2nd Ed.; Prentice Hall: Sydney, 1998. |
Kieran F. Lim ( ) obtained his BSc (Hons) and PhD in theoretical chemistry from the University of Sydney. He was awarded an Archbishop Mannix Travelling Scholarship to Stanford University and been a faculty member at the University of New England, the University of Melbourne and Deakin University, where he is currently... |
Dr Lim is a recipient of the Royal Australian Chemical Institute's Division of Chemical Education Citation for significant contributions to chemical education (2002) and the Faculty of Science and Technology's Excellence in Teaching Award (1996 and 2000). |
New materials pictured below are coming soon! We still have current materials on hand, so let us know what you need. |
Two-sided information card. 2" x 3.5" |
Agora can provide you with posters, brochures and cards to give out to your friends, family, neighbors, clients, students...or anyone else you can think of! |
The acclaimed British artist is having a moment. |
David Hockney, Woldgate Woods, 24, 25 and 26 October, 2006(2006). The painting carries a $9 million–12 million estimate, which would set a new auction record for the artist. Courtesy of Sotheby’s New York. |
Records could fall at Sotheby’s New York “Contemporary Art Evening Auction” on November 17, where the house is predicting a mammoth $9 million–12 million hammer price for Woldgate Woods, 24, 25 and 26, 2006, a massive 2006 landscape painting by David Hockney. |
The acclaimed British artist is having a moment, riding off this summer’s international release of Randall Wright’s documentary Hockney, and looking ahead to the publication of his new book with art critic Martin Gayford, A History of Pictures: From the Cave to the Computer Screen, due out October 18. |
Hockney, who will turn 80 next year, will also be the subject of a massive retrospective at Tate Britain, scheduled to run February 9–May 29, 2017. Billed as his most comprehensive exhibition to date, the show will include a number of never-before-seen works. |
David Hockney, Beverly Hills Housewife(1966–67). Courtesy of Christie’s New York. |
According to the artnet Price Database, Hockney’s current record at auction is $7.92 million, set in May 2009 at Christie’s New York with Beverly Hills Housewife. The 1966–67 diptych, from the “California Dreaming” series, is a portrait of the late art philanthropist and photographer Betty Freeman in front of her Los A... |
The artist has had five other sales in excess of $5 million, all over the last 10 years. |
This number appears to be somewhat of a sweet spot for Hockney, as none of those lots topped $5.5 million. The first sale at that price point came in 2006 at Sotheby’s London, for the iconic 1966 swimming pool painting, The Splash. |
David Hockney, The Splash (1966). Courtesy of Sotheby’s London. |
A Yorkshire native, Hockney took to the Woldgate Woods in 2006, painting en plein air throughout the seasons, documenting the changes in light and color over the course of the year. He wanted to work on a monumental scale, but the large canvases he had in mind wouldn’t fit up the stairs at his studio, so he combined a ... |
David Hockney painting May 17th 2006, Woldgate Woods, East Yorkshire. Courtesy of Sotheby’s, photo © Jean-Pierra Goncalves de Lima, artwork © David Hockney. |
Three prints of works depicting Woldgate have come to auction in recent years (two fetched under $1,000, the third went unsold), but the upcoming sale marks a first for one of the original canvases. |
David Hockney, Woldgate Woods 2006(2006). Courtesy of Venator & Hanstein, Germany. |
“With the opening of the Tate retrospective early next year, along with collectors’ tremendous appetite for quality, now is the perfect time to present one of the great accomplishments of the artist’s late career,” said Grégoire Billault, head of the contemporary art department, in a statement. |
Ahead of the sale, Woldgate Woods will be on view at Sotheby’s London October 1–7, 2016, and at Sotheby’s New York November 4–17. Other potential big ticket items at the auction include a pair of Willem de Kooning canvases—Untitled (1976–77) and Untitled XXXIX (1983)—both of which could fetch $8 million–12 million. |
Ciclesonide is used to prevent and reduce the symptoms (wheezing and shortness of breath) caused by asthma. Controlling asthma symptoms may decrease time lost from work or school. This medication belongs to a class of drugs known as corticosteroids. It works by reducing the swelling of the airways in the lungs to make ... |
At the first European Forum Let’s Liberate Diversity! in Poitiers, France, the idea has emerged on the creation of a European network committed to the conservation and renewal of crop biodiversity in farms and gardens. First, an informal network has been established with the aim to organize exchanges among different co... |
Exchanging information and experiences between member organizations at the European level as well as partners outside of Europe, particularly in the Mediterranean region. |
The 6th European forum “Let’s Liberate Diversity!” on agricultural biodiversity took place on February 25-26, 2011 in Szeged, Hungary. |
The Let’s Liberate Diversity! forums are the annual gatherings of farmers’ organisations and associations working on agricultural biodiversity in Europe. |
The 2011 edition of the forum will be held in Szeged, Hungary, during the Hungarian presidency of the European Union. Its central theme will be the question of Farmers’ Rights related to the conservation, sustainable use and development of agricultural biodiversity. |
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