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Melvin A. Neuman helped characterize an iron carbonyl tetramer containing a bonded four-metal metal cluster. The structure consists of interpenetrating tetrahedra of iron atoms and bridging carbonyl carbon atoms, giving a concrete example of how diffraction reveals metal–metal connectivity.[ref]
Trinh-Toan helped characterize an iron carbonyl tetramer by diffraction. Its four metal atoms form a bonded tetrahedron, interpenetrated by a second tetrahedron of triply bridging carbonyl carbon atoms. The result is a concrete structural example of a metal metal cluster.[ref]
Lawrence F. Dahl investigated the structure of an iron carbonyl tetramer by diffraction. Four bonded iron atoms form a tetrahedron, while four triply bridging carbonyl carbon atoms form an interpenetrating tetrahedron, connecting an unusual molecular geometry with metal–metal bonding.[ref]
Structural Characterization of the Cyclopentadienyliron Carbonyl Tetramer, Fe4(eta5-C5H5)4(CO)4. A Cubane-Type Structure Containing a Completely Bonding Tetrametal Cluster Unit by Melvin A. Neuman and others. 1972, pp.3383–3388: original diffraction structure and tetrametal cluster unit
Iridium is the chemical element with atomic number 77 and symbol . It is a transition metal. It is a dense platinum-group metal with strong corrosion resistance. Iridium-containing complexes and oxides can serve as catalysts, illustrating how oxidation state and coordination change the behavior of a chemically resistant bulk metal.
A crystal structure specifies the chemical species and spatial arrangement of the chemical atoms or ions in a crystal. For an ideal periodic structure, separate two ingredients: a Bravais lattice specifies the translations that repeat the arrangement, and an atomic basis of a crystal specifies the chemical motif repeated at every lattice point. The outward shape, or crystal habit, is a different description: the internal arrangement is what this article describes.
A crystal structure specifies the chemical species and spatial arrangement of the chemical atoms or ions in a crystal. For an ideal periodic structure, separate two ingredients: a Bravais lattice specifies the translations that repeat the arrangement, and an atomic basis of a crystal specifies the chemical motif repeated at every lattice point. The outward shape, or crystal habit, is a different description: the internal arrangement is what this article describes.
A crystal structure specifies the chemical species and spatial arrangement of the chemical atoms or ions in a crystal. For an ideal periodic structure, separate two ingredients: a Bravais lattice specifies the translations that repeat the arrangement, and an atomic basis of a crystal specifies the chemical motif repeated at every lattice point. The outward shape, or crystal habit, is a different description: the internal arrangement is what this article describes.
A crystal structure specifies the chemical species and spatial arrangement of the chemical atoms or ions in a crystal. For an ideal periodic structure, separate two ingredients: a Bravais lattice specifies the translations that repeat the arrangement, and an atomic basis of a crystal specifies the chemical motif repeated at every lattice point. The outward shape, or crystal habit, is a different description: the internal arrangement is what this article describes.
Theodore K. Koenig coauthored aircraft measurements of iodine species in the stratosphere. Observations of iodine monoxide and particulate iodine constrain delivery of iodine and exchange between gas and particle phases.
Measuring one reactive gas is not the same as measuring the full elemental inventory. Combining species measurements helps connect observed radical abundance with catalytic ozone loss.[ref]
Quantitative detection of iodine in the stratosphere by Theodore K. Koenig and others. Research topic and author attribution in the primary publication
Nicola J. Warwick coauthored modelling of the atmospheric and climatic effects of a future hydrogen economy. The analysis separates leaked molecular hydrogen from changes in other emissions associated with energy-system replacement.
Hydrogen leakage can alter atmospheric oxidation chemistry, affecting methane and ozone. Consequently, the climate effect depends on both leakage and the emissions displaced by the new system.[ref]
Atmospheric composition and climate impacts of a future hydrogen economy by Nicola J. Warwick and others. Research topic and author attribution in the primary publication
Sophie Szopa coauthored the IPCC assessment chapter on short-lived climate forcers. Its treatment of methane separates an atmospheric burden's chemical removal time from the relaxation time of a methane perturbation.
Additional methane can change the abundance of the hydroxyl radical that removes it. This chemical feedback makes the perturbation lifetime a coupled-system property rather than a simple fixed loss constant.[ref]
Short-lived Climate Forcers by Sophie Szopa and others. Research topic and author attribution in the primary publication
P. Heckendorn coauthored coupled aerosol and chemistry-climate simulations of stratospheric aerosol injection. The study examines effects on stratospheric temperature and ozone, rather than treating injected mass as a fixed amount of cooling.
Particle growth changes scattering and settling, while temperature and chemical changes affect ozone. These coupled responses explain why aerosol amount alone does not determine the climatic outcome.[ref]
The impact of geoengineering aerosols on stratospheric temperature and ozone by P. Heckendorn and others. Research topic and author attribution in the primary publication
E. R. Vance coauthored research on the crystal chemistry and phase control of Synroc. The scientific problem is to distribute waste elements among stable ceramic phases with suitable crystal sites.
Changing the overall composition can change which phases form and which ions each phase incorporates. This links phase equilibrium and crystal structure to the chemical durability of a waste form.[ref]
Crystal chemistry and phase manipulation in Synroc by E. R. Vance and others. Research topic and author attribution in the primary publication
B. D. Begg coauthored research on plutonium substitution at zirconium sites in zirconolite. The reported structural changes include transitions between zirconolite variants and a pyrochlore-related structure.
Replacing one ion by another can change preferred coordination and charge compensation. A nominal substitution is consequently a hypothesis about a crystal's atomic sites, not merely a change in its bulk elemental recipe.[ref]
Structural Effect of Pu Substitutions on the Zr-Site in Zirconolite by B. D. Begg and others. Research topic and author attribution in the primary publication
M. W. A. Stewart coauthored research on solid forms for immobilizing wastes from reactor production of molybdenum-99. The work connects material composition with the long-term behaviour of uranium-bearing waste.
Incorporation of suitable neutron absorbers addresses a different property from resistance to aqueous dissolution. A useful waste form must account for both nuclear composition and chemical durability.[ref]
Immobilisation of Higher Activity Wastes from Nuclear Reactor Production of 99Mo by M. W. A. Stewart and others. Research topic and author attribution in the primary publication
B. P. McGrail coauthored measurements of dissolution kinetics in a sodium-calcium-aluminium borosilicate glass developed for waste immobilization. Flow-through experiments and blanks help separate material release from background signals and transport effects.
A measured dissolved concentration is therefore not automatically an intrinsic reaction rate: flow, solution chemistry, and surface area enter the interpretation.[ref]
Measurement of kinetic rate law parameters on a Na-Ca-Al borosilicate glass for low-activity waste by B. P. McGrail and others. Research topic and author attribution in the primary publication
S. Muraoka led a reported Japanese-Australian study of radiation damage and actinide behaviour in Synroc. The research concerns a multiphase ceramic designed to incorporate radioactive elements into crystalline hosts.
Radiation damage and chemical retention are linked but distinct questions: a host can lose structural order while still retaining an element, or preserve order while undergoing selective chemical release.[ref]
JAERI/ANSTO co-operative research on radiation damage and actinide behaviour in Synroc by S. Muraoka and others. Research topic and author attribution in the primary publication
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact