1,721,470 research outputs found
Archeometria ed Archeologia: il fascino di un amore difficile.
No full textThe difficult but fascinating relationship between archaeometry and archaeology continuously offers challenges and topics for discussion. A few personal thoughts were stimulated by the recent publication of the revised versions of volumes having a substantial archaeometric content and an interesting methodological approach
Scientific methods and the cultural heritage. An introduction to the application of materials science to archaeometry and conservation science.
No full textThe book is intended as an entry-level introduction to the methods and rationales of scientific investigation of cultural heritage materials, with emphasis placed on the analytical strategies, modes of operation, and resulting information rather than on technicalities. The extensive and updated reference list should be a useful starting point for further reading. Students and researchers from the humanities approaching scientific investigations should find it useful, as well as scientists applying familiar techniques and methods to unfamiliar problems related to cultural heritage
Utilizzo della luce di sincrotrone nelle Scienze della Terra
No full textSyJlchrotnm radiljltion is todaythe most powctft.l source oi Xrays
in ine high energy tegioll. Most research filJldsil1 the
Earih Scienceshauestarted to. :takeadvantage of iheintense
!iynchrotran sqf<Fces and of .ehe pec!11iarcharactel'istics of the
emitied .radiatidntò ir,npr:ove our J...-nmq/edgeof thw suucture,
bçnding ana, èlJmposrliQIJ ofF:ar.th maieiials. To date ihe largest
l1umber oJ experimeni« haue been per/ormed in thè area oJ
.X-ray sedtterin:g; e~peèiti.lly with Bragg-difftaction techniques.
and X-ray llbAorpliiln;·especially with XANES and EXAFS techniquee.
AmO;J1:g a variety of nove! applications, ihe use oJ
synchròtrorì,;g;.Pllys:·Ìi<sca.~ring and obsorptionexperimeats
.allow In 5ìw. stuiIies.ofminemlsl1nd me/ts al high temperature
and. pressllre~1 hWumlò nnaceessible 011Ìllboratory aources.
A numoer bf r!jffetàit experimentol meihàd« also tah 'aduantase
oJ th« fli~b~lfty, brightness, rind in(riiisic COllima/ion oj
synehrOtton rarfiabiorr, and tliey yie1d chemioai and physiçal
tnfonnaHon aJ great impact 'in t1Je study of Earth arid planetarlj
processes. Among tl,'esè teçhniquee are: synchrotron induéed
X-ray enf~sion a11'fJ.lysis ojabundance and distribwtion
af trace elelp11ts' iI!'è,OJJflen.sl1dmrde.ria.'/sand flui4 incl!lsiòl1S,
X-ray topogri lowelement
eoneentrati011S', éxireme H'TfHP eonaWbns, and rapld data acquisition
TI;qurrea:lrgdYlta;nic proceeeesand. reaciicnkineues
The crystal structure of garronite
No full textThe structures of the natural zeolite garronite, NaCa2.5Al6Si10O32.13H2O, from Goble, Oregon, and Fara Vicentina, Italy, have been determined and refined by X-ray powder diffraction methods with the use of the full-profile Rietveld technique. The framework topology has the gismondine structure type (GIS), although the topological symmetry I4(1)/amd is lowered to I4BARm2. Cell dimensions are Goble, a = 9.9266(2), c = 10.3031(3) angstrom; Fara Vicentina, a = 9.8712(2), c = 10.2987(3) angstrom. The space group assumed in the refinements accounts for the presence in the garronite powder pattern of reflections violating the d glide extinctions. Deviation from the maximum framework symmetry can be explained in terms of cation and H2O arrangements in the zeolitic cavities
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