Archaeobotany in urban sites: the case of Mutina

The present paper aims to show the importance of analyzing plant macroremains from urban excavations. organic materials preserved below the historical city in waterlogged conditions are a fundamental resource, and the study of seeds and fruits gives a good contribution to historical and archaeological research. archaeobotany in urban contexts provides important results when the examined material comes from several excavations that \u201cphotograph\u201d the territory over quite a long period. an overview of archaeobotanical analyses carried out on material from archaeological sites of Modena (Emilia-Romagna), from the 2nd century BC to the 6th century ad, made by the laboratory of palynology and palaeobotany of the University of Modena and Reggio Emilia, is presented. The floristic list of seed/fruit analyses result is reported and interesting subject matters are tackled concerning both cultivated/cultivable plants (fruits and nuts, vegetables/aromatics/spices/medicinal plants, fibre and oil plants, cereals and pulses, flowers and other ornamental plants) and wild plants of no obvious use, together with wetland plants which are rare and endangered species in Emilia-Romagna today

Synergistic catalysis: cis-cyclopropanation of benzoxazoles

In the present paper we report our latest efforts in pushing the boundaries of Synergistic Catalysis. We propose the use of 3 different catalytic cycles working in concert for the formation of cis cyclopropane derivatives of benzoxazoles with excellent stereoselectivities. This is the proof of concept that synergistic catalysis could be successfully used in cascade reaction

Analisi carpologiche per la Vasca dello Specchio (Ferrara, XIV-XV sec. d.C.): metodologie d’indagine e risultati

Lo scavo condotto tra Corso Porta Reno e Via Vaspergolo, nel centro storico di Ferrara, ha portato alla luce un vano sotterraneo rettangolare denominato “Vasca dello Specchio”, utilizzato per lo smaltimento dei rifiuti tra XIV e XV secolo. Il riempimento, in parte già analizzato e pubblicato, è stato oggetto di nuove analisi carpologiche. I semi e i frutti, conservati prevalentemente per sommersione e in ottimo stato, sono complessivamente oltre 400.000 e la lista floristica comprende 168 taxa. La maggior parte dei reperti appartiene a piante coltivate/coltivabili o spontanee correlate all’uomo, che forniscono nuove informazioni sulla dieta vegetale e sull’ambiente urbano della Ferrara basso-medievale/rinascimentale. I reperti evidenziano anche pratiche domestiche e culinarie talora curiose

Le Piante e la Gloria: una mostra tra Botanica e Filosofia

L’Orto Botanico di Modena collabora da quattro anni con il Festival-Filosofia Modena/Carpi/Sassuolo, ospitando nella sua suggestiva cornice diverse esposizioni e iniziative artistiche e organizzando laboratori per bambini attinenti al tema della manifestazione. Nel 2014 per il tema Gloria è stata proposta la mostra “Gloria in Cielo, Verde sulla Terra. Iconologia vegetale nelle immaginette sacre”, presentando oltre trecento “santini” (1800-1930), da collezioni private, con simboli vegetali caratterizzanti legati a figure sacre e momenti del rito cristiano. Sono così nate le varie sezioni della mostra: il giglio, la palma, la rosa, la vite e l’uva, l’erbario e il giardino mariano, le piante della Passione ecc. La collocazione nelle vetrine dell’Aula Storica dell’Orto ha permesso di affiancare a immaginette e poster i vegetali, freschi o essiccati, dando così materialità al legame tra botanica e gloria celeste. Ancora una volta l’associazione piante-arte si è dimostrata un grande catalizzatore d’interesse e curiosità, portando i visitatori a vivaci scambi tra loro e con il personale addetto all’esposizione

La Xiloteca Storica dell’Orto Botanico di Modena

Nell’ambito dei progetti di valorizzazione museale delle collezioni storiche, in corso presso l’Orto Botanico dell’Università di Modena e Reggio Emilia, un recente intervento ha riguardato la Xiloteca Storica e, in particolare, 345 campioni di legno acquisiti nel periodo 1890-1969, provenienti sia da esemplari abbattuti nell’Orto Botanico modenese che da raccolte effettuate in natura oppure da donazioni da parte di istituzioni o privati

Four-electron Reduction and Functionalization of N₂ by a Uranium(III) Bridging Nitride

N2 is a cheap and widely available but very unreactive molecule. Notably, the only industrial process for the conversion of dinitrogen is the Haber-Bosch process to form ammonia, but under very harsh conditions (high temperature and pressure). Here, we review our recent research leading to the reduction of dinitrogen by four electrons, under ambient conditions by a uranium(III) bridging nitride, K3 U-N-U, where two uranium(III) cations are linked by a nitride group and a flexible metal-ligand scaffold. We also show that the bound dinitrogen can be further functionalized under mild conditions: the addition of acid, hydrogen and protons or carbon monoxide to the uranium hydrazido complex yields to the cleavage of the N-N single bond and to the formation of new N-H and N-C bonds

Combining satellite multispectral imagery and topographic data for the detection and mapping of fluvial avulsion processes in lowland areas

Fluvial avulsion is an important process in the dynamics of the riverscapes and plays a key role in the drainage network evolution in lowland areas, also influencing past and present social processes and economic activities. Crevasse splays represent significant geomorphological features for understanding the fluvial morphodynamics in lowland areas dominated by avulsion processes. Within wide floodplains characterized by very low elevation ranges, the detection and accurate mapping of crevasse splay morphology and features, such as crevasse channels, levees, and deposit, can be very challenging considering floodplain extension, anthropic impact on the natural channels network, logistic difficulties, and in some cases, climate conditions that prevent field work. This research aims at improving the detection and mapping of crevasse splays in lowland areas through the combination of different remote sensing techniques based on optical multispectral imagery and topographic data derived from satellite earth observation missions. The Lower Mesopotamia Plain (LMP) offers a unique opportunity to study the avulsion processes because it presents numerous examples of crevasse splays, characterized by different sizes and states of activity. Furthermore, in this area, a strong correlation exists between the formation and development of crevasse splays and the expansion of agriculture and early societies since the Early Holocene. Different supervised classification (SC) methods of Landsat 8 satellite images have been tested together with topographic analysis of the microrelief, carried out based on two different 1-arcsec DEMs (AW3D30 and GDEM2). The results of this study demonstrate that the combination of multispectral imagery analysis and topographic analysis of the microrelief is useful for discerning different crevasse elements, distinguishing between active and relict landforms. The methodological approach proved helpful for improving the mapping of erosional and depositional landforms generated by the avulsion process and, in the study area, provided the best results for the active landforms

CO Cleavage and CO2 Functionalization under Mild Conditions by a Multimetallic CsU2 Nitride Complex

Novel efficient chemical processes involving cheap and widely accessible carbon dioxide or carbon monoxide under mild conditions for the production of valuable chemical products are highly desirable in the current energetic context. Uranium nitride materials act as high activity catalysts in the Haber-Bosch process but the reactivity of molecular nitride compounds remains unexplored. Here we review recent results obtained in our group showing that a multimetallic nitride complex [Cs{[U(OSi(OtBu)(3))(3)](2)(mu-N)}] (1) with a CsUIV-N-U-IV core, is able to promote N-C bond formation due to its strong nucleophile behaviour. In particular, complex 1, in the presence of excess CO2 leads to a remarkable dicarbamate product. The multimetallic CsUIV-N-U-IV nitride also readily cleaves the C O bond under mild conditions

Nitrogen reduction and functionalization by a multimetallic uranium nitride complex

Molecular nitrogen (N-2) is cheap and widely available, but its unreactive nature is a challenge when attempting to functionalize it under mild conditions with other widely available substrates (such as carbon monoxide, CO) to produce value-added compounds. Biological N-2 fixation can do this, but the industrial Haber–Bosch process for ammonia production operates under harsh conditions (450 degrees Celsius and 300 bar), even though both processes are thought to involve multimetallic catalytic sites (1, 2). And although molecular complexes capable of binding and even reducing N-2 under mild conditions are known, with co-operativity between metal centres considered crucial for the N-2 reduction step (1-14), the multimetallic species involved are usually not well defined, and further transformation of N-2-binding complexes to achieve N–H or N–C bond formation is rare (2, 6, 8, 10, 15, 16). Haber noted (17), before an iron-based catalyst was adopted for the industrial Haber–Bosch process, that uranium and uranium nitride materials are very effective heterogeneous catalysts for ammonia production from N-2. However, few examples of uranium complexes binding N-2 are known (18-22), and soluble uranium complexes capable of transforming N-2 into ammonia or organonitrogen compounds have not yet been identified. Here we report the four-electron reduction of N-2 under ambient conditions by a fully characterized complex with two U-iii ions and three K+ centres held together by a nitride group and a flexible metalloligand framework. The addition of H-2 and/or protons, or CO to the resulting N-2(4-)complex results in the complete cleavage of N-2 with concomitant N-2 functionalization through N–H or N–C bond-forming reactions. These observations establish that a molecular uranium complex can promote the stoichiometric transformation of N-2 into NH3 or cyanate, and that a flexible, electron-rich, multimetallic, nitride-bridged core unit is a promising starting point for the design of molecular complexes capable of cleaving and functionalizing N-2 under mild conditions

Reversible Dihydrogen Activation and Hydride Transfer by a Uranium Nitride Complex

Abstract: Cleavage of dihydrogen is an important step in the industrial and enzymatic transformation of N2 into ammonia. The reversible cleavage of dihydrogen was achieved under mild conditions (room temperature and 1 atmosphere of H2) by the molecular uranium nitride complex, [Cs{U(OSi-(OtBu)3)3}2(m-N)] 1, leading to a rare hydride–imide bridged diuranium(IV) complex, [Cs{U(OSi(OtBu)3)3}2(m-H)(m- NH)], 2 that slowly releases H2 under vacuum. This complex is highly reactive and quickly transfers hydride to acetonitrile and carbon dioxide at room temperature, affording the ketimide- and formate-bridged UIV species [Cs{U(OSi-(OtBu)3)3}2(m-NH)(m-CH3CHN)], 3 and [Cs{U(OSi-(OtBu)3)3}2(m-HCOO)(m-NHCOO)], 4