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NMR investigation of degradation processes of ancient and modern paper at different hydration levels

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Frontiers of physics 2018年第1期13卷 41-50页

作者： Domenico Mallamace Sebastiano Vasi Mauro Missori Francesco Mallamace Carmelo Corsaro consorzio interuniversitario per lo sviluppo dei Sistemi a Grande Interfase - CSGI Via della Lastruccia 3 50019 Sesto Fiorentino Firenze Italy Dipartimento MIFT Sezione di Fisica Universita di Messina Viale F. Stagno D'Alcontres 31 98166 Messina Italy Istituto dei Sistemi Complessi Consiglio Nazionale delle Ricerche Unit Sapienza Piazzale Aldo Moro 5 00185 Roma Italy CNR-IPCF Messina Istituto per i Processi Chimico-Fisici Viale F. Stagno D'Alcontres 37 98158 Messina Italy Center for Polymer Studies and Department of Physics Boston University Boston MA 02215 USA

The degradation process of cellulose-made materials was investigated by means of nuclear magnetic resonance （NMR） spectroscopy, with particular emphasis on the role of water and on the hydration mechanism of cellulose fibrils. To accomplish this, the structure and dynamics of water within ancient and modern samples with different aging histories were investigated. The results mainly indicated that hydrolytic and oxidative reactions provoked the formation of acidic by-products. Furthermore, degradation processes were enhanced by higher amounts of water giving a progressive consumption of the amorphous regions of the cellulose. We propose NMR experiments as a benchmark for character- ization of the degradation state of paper, as well as for investigating the effectiveness of restoration treatments.

关键词： ancient paper degradation NMR hydration solvent dynamics

Raman investigation of air-stable silicene nanosheetson an inert graphite surface

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Nano Research 2018年第11期11卷 5879-5889页

作者： Paola Castrucci Filippo Fabbri Tiziano Delise Manuela Scarselli Matteo Salvato Sara Paseale Roberto Francini Isabelle Berbezier Christoph Lechner Fatme Jardali Holger Vach Maurizio De Crescenzi Dipartimento di Fisica Universita di Roma 'Tor Vergata' Roma 00133 Italy Center for Nanotechnology Innovation c/o NEST Istituto Italiano di Tecnologia Pisa 55127 Italy consorzio di Ricerca Hypatia c/o Italian Space Agency Roma O0133 Italy Dipartimento di Ingegnefia Industfiale Universita di Roma "For Vergata" Roma O0133 Italy CNRS Aix-Marseille UniversitY IM2NP UMR 7334 Marseille 13397 France EDF R&D Department Matefials and Mechanics of Components (MMC) Moret-sur-Loing 77818 France CNRS-LPICM Ecole Polytechnique Universitd Paris-Saclay Palaiseau 91128 France

The fascinating properties of two dimensional (2D) crystals have gained increasing interest for many applications. The synthesis of a 2D silicon structure, namely silicene, is attracting great interest for possible development of next generation electronic devices. The main difficulty in working with silicene remains its strong tendency to oxidation when exposed to air as a consequence of its relatively highly buckled structure. In this work, we univocally identify the Raman mode of air-stable low-buckled silicene nanosheets synthesized on highly oriented pyrolytic graphite (HOPG) located at 542.5 cm-1. The main focus of this work is Raman spectroscopy and mapping analyses in combination with ab initio calculations. Scanning tunneling microscopy images reveal the presence of a patchwork of Si three-dimensional (3D) clusters and contiguous Si areas presenting a honeycomb atomic arrangement, rotated by 30 degrees with respect to the HOPG substrate underneath, with a lattice parameter of 0.41 +/- 0.02 nm and a buckling of the Si atoms of 0.05 nm. Raman analysis supports the co-existence of 3D silicon clusters and 2D silicene. The Raman shift of low-buckled silicene on an inert substrate has not been reported so far and it is completely different from the one calculated for free-standing silicene and the ones measured for silicene grown on Ag(111) surfaces. Our experimental results are perfectly reproduced by our ab initio calculations of deposited silicene nanosheets. This leads us to conclude that the precise value of the observed Raman shift crucially depends on the strain between the silicene and the HOPG substrate.

关键词： 2D materials silicene Raman spectroscopy ab initio calculations scanning tunneling microscopy scanning tunneling spectroscopy

阿司匹林可用于糖尿病患者CVD一级预防吗?

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糖尿病天地(临床) 2011年第6期5卷 264-266页

作者：安东尼奥庄稼英意大利consorzio Mario Negri Sud研究所临床药理和流行病医学部

心血管疾病(CVD)是糖尿病患者死亡的主要原因。除了与几个经典的心血管危险因素相关外,糖尿病还会加速动脉粥样硬化和炎症的进展,进而促使CVD并发症的发生。基于此,旨在降低缺血

关键词：糖尿病患者阿司匹林乙酰水杨酸一级预防 CVD

Vegetation Dynamism in the Mixed Conifer/Broadleaves Species Artificial Stands Crossed by Fire： The Arci Mountain Case Study in Sardinia

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Journal of Environmental Science and Engineering(B) 2012年第5期1卷 606-610页

作者： Michele Puxeddu Simona Pallanza Giorgio Citterio Raffaello Giannini Sardinia Forest Agency Loc. Campulongu Oristano 09070 Italy Sardinia Forest Corp via Donizetti 15 Oristano 09070 Italy consorzio Sa Corona Arrubia Villanovaforru Lodine (U) 08020 Italy University of Florence via S. Bonaventura 13 Florence 50145 Italy

Immediate cutting and logging of mixed conifer/broadleaves species in a man-made forest crossed by fire in 2009 in the Arci Mountain in Sardinia can not guarantee as the best post-fire regeneration. The study case reports the differences in the density and in the height of seedlings. The release of damaged Pinus halepensis Mill. stems seems to confirm the tree seeder role of this species.

关键词： Man-made forest post-fire regeneration Pinus halepensis Quercus ilex Quercus suber.

Monitoring Domoic Acid in Marine Phytoplankton by Disposable Immunosensors

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American Journal of Plant Sciences 2017年第5期8卷 1077-1091页

作者： Roberta Congestri Laura Micheli Giuseppe Palleschi Laboratory of Biology of Algae Department of Biology University of Rome “Tor Vergata”—Via Cracovia 1 Rome Italy Department of Chemical Sciences and Technologies University of Rome “Tor Vergata”—Via della Ricerca Scientifica Rome Italy consorzio Interuniversitario Biostrutture e Biosistemi “INBB” Viale Medaglie d’Oro 305 Rome Italy

Advances in sensor technology have allowed the significant progress in the monitoring of noxious compounds in the sea, providing real-time detection so as to prevent risks associated with the diffusion and dispersion of toxic substances in the environment. An important element in the overall picture is the harmful algal blooms which pose serious threats to marine ecosystems through the production of toxins that accumulate in filter-feeders and ultimately impact both human health and fisheries. Domoic acid is a neurotoxic amino acid produced by marine planktonic diatoms of the genus Pseudo-nitzschia. Here we monitored domoic acid production by natural Pseudo-nitzschia populations in phytoplankton samples collected along the Middle Tyrrhenian coast, over the course of one year, using selective immunosensors based on screenprinted electrodes, using differential pulse voltammetry as the electrochemical technique, to yield quantitative outputs. In this work, disposable devices have been applied for monitoring the production of domoic acid on algal extracts and the results have been validated by conventional high pressure liquid chromatography-ultraviolet detection methods. The data obtained revealed the presence of domoic acid in Italian phytoplankton, especially in coastal impacted areas, highlighting the potential risk of toxin entering into marine food webs and the environment. Immunosensors based on screen-printed electrodes prove to be effective tools for annual monitoring of domoic acid in seawater samples, thus providing a reliable early warning system relative to health and economic impact of algal toxins.

关键词： Domoic Acid Monitoring Immunosensors Screen Printed Electrodes Toxic Pseudo-nitzschia

Stable Methylammonium-Free p-i-n Perovskite Solar Cells and Mini-Modules with Phenothiazine Dimers as Hole-Transporting Materials

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Energy & Environmental Materials 2023年第6期6卷 383-392页

作者： Luigi Angelo Castriotta Rossella Infantino Luigi Vesce Maurizio Stefanelli Alessio Dessì Carmen Coppola Massimo Calamante Gianna Reginato Alessandro Mordini Adalgisa Sinicropi Aldo Di Carlo Lorenzo Zani Centre for Hybrid and Organic Solar Energy(C.H.O.S.E.) Department of Electronic EngineeringUniversity of Rome Tor Vergata00133 RomeItaly Institute of Chemistry of Organometallic Compounds(CNR-ICCOM) Via Madonna del Piano 1050019 Sesto FiorentinoItaly Department of Biotechnology Chemistry and PharmacyUniversity of SienaVia Aldo Moro 253100 SienaItaly CSGI Consorzio per lo Sviluppo dei Sistemi a Grande InterfaseVia della Lastruccia 350019 Sesto FiorentinoItaly Department of Chemistry“U.Schiff” University of FlorenceVia della Lastruccia 1350019 Sesto FiorentinoItaly Institute of Structure of Matter(CNR-ISM) Via del Fosso del Cavaliere 10000133 RomeItaly

During the last decade,perovskite solar technologies underwent an impressive development,with power conversion efficiencies reaching 25.5%for single-junction devices and 29.8%for Silicon-Perovskite tandem *** though research mainly focused on improving the efficiency of perovskite photovoltaics(PV),stability and scalability remain fundamental aspects of a mature photovoltaics *** n-i-p structure perovskite solar cells,using poly-triaryl(amine)(PTAA)as hole transport layer(HTL)allowed to achieve marked improvements in device stability compared with other common hole *** p-i-n structure,poly-triaryl(amine)is also routinely used as dopant-free hole transport layer,but problems in perovskite film growth,and its limited resistance to stress and imperfect batch-to-batch reproducibility,hamper its use for device *** previous computational investigations,in this work,we report the synthesis of two small-molecule organic hole transport layers(BPT-1,2),aiming to solve the above-mentioned issues and allow upscale to the module *** using BPT-1 and methylammonium-free perovskite,*** conversion efficiencies of 17.26%and 15.42%on a small area(0.09 cm^(2))and mini-module size(2.25 cm^(2)),respectively,were obtained,with a better reproducibility than with poly-triaryl(amine).Moreover,BPT-1 was demonstrated to yield more stable devices compared with poly-triaryl(amine)under ISOS-D1,T1,and L1 accelerated life-test protocols,reaching maximum T_(90)values>1000 h on all tests.

关键词： methylammonium-free perovskite mini-modules organic hole-transporting layers perovskite solar cells stability studies

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Covalent functionalization of decellularized tissues accelerates endothelialization

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Bioactive Materials 2021年第11期6卷 3851-3864页

作者： Eleonora Dal Sasso Annj Zamuner Andrea Filippi Filippo Romanato Tiziana Palmosi Luca Vedovelli Dario Gregori Jose Luís Gòmez Ribelles Teresa Russo Antonio Gloria Laura Iop Gino Gerosa Monica Dettin Department of Cardiac Thoracic and Vascular Sciences and Venetian Institute of Molecular MedicinePaduaItaly Department of Industrial Engineering University of PaduaPaduaItaly LIFELAB Program Consorzio per la Ricerca SanitariaCORISVeneto RegionItaly Department of Physics and Astronomy“G.Galilei” University of PaduaPaduaItaly Fondazione Bruno Kessler TrentoItaly Institute of Pediatric Research Citt`a della Speranza PaduaItaly Center for Biomaterials and Tissue Engineering CBITUniversitat Polit`ecnica de Val`enciaVal`enciaSpain Biomedical Research Networking Center on Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)ValenciaSpain Institute of Polymers Composites and BiomaterialsNational Research Council of ItalyNaplesItaly

In the field of tissue regeneration,the lack of a stable endothelial lining may affect the hemocompatibility of both synthetic and biological *** drawbacks might be prevented by specific biomaterial functionalization to induce selective endothelial cell(EC)*** bovine pericardia and porcine aortas were selectively functionalized with a REDV tetrapeptide at 10^(-5)M and 10^(-6)M working *** scaffold-bound peptide was quantified and REDV potential EC adhesion enhancement was evaluated in vitro by static seeding of human umbilical vein *** viable cells and MTS production were statistically higher in functionalized tissues than in *** histoarchitecture,geometrical features,and mechanical properties were unaffected by peptide *** selective immobilization of REDV was effective in accelerating ECs adhesion while promoting proliferation in functionalized decellularized tissues intended for blood-contacting applications.

关键词： Decellularized pericardium Decellularized aorta Covalent functionalization Endothelialization REDV Mechanical analysis

Evaluation of mercury biogeochemical cycling at the sediment–water interface in anthropogenically modified lagoon environments

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Journal of Environmental Sciences 2018年第6期30卷 5-23页

作者： Elisa Petranich Stefano Covelli Alessandro Acquavita Jadran Faganeli Milena Horvat Marco Contin Dipartimento di Matematica e Geoscienze Universita degli Studi di Trieste Via Weiss 2 34128 Trieste Italy Dipartimento di Scienze della Vita Universita degli Studi di Trieste Via Licio Giorgieri 5 34128 Trieste Italy CoN.I.S.Ma. consorzio Nazionale Interuniversitario per le Scienze del Mare Piazzale Flaminio 9 00196 Rome Italy Agenzia Regionale per la Protezione Ambientale del Friuli Venezia Giulia ARPA FVC Via Cairoli 14 33057 Palmanoua (Udine) Italy Marine Biological Station Fornace 41 6330 Piran Slovenia Department of Environmental Sciences Joker Stefan Institute Jamova 39 1000 Ljubljana Slovenia Dipartimento di Scienze Agro-Alimentari Ambientali e Animali Universita di Udine Via delle Scienze 206 33100 Udine Italy

The Marano and Grado Lagoon is well known for being contaminated by mercury（Hg） from the Idrija mine（Slovenia） and the decommissioned chlor-alkali plant of Torviscosa（Italy）.Experimental activities were conducted in a local fish farm to understand Hg cycling at the sediment–water interface. Both diffusive and benthic fluxes were estimated in terms of chemical and physical features. Mercury concentration in sediments（up to 6.81 μg/g）showed a slight variability with depth, whereas the highest methylmercury（MeHg） values（up to 10 ng/g） were detected in the first centimetres. MeHg seems to be produced and stored in the 2–3 cm below the sediment–water interface, where sulphate reducing bacteria activity occurs and hypoxic–anoxic conditions become persistent for days. DMeHg in porewaters varied seasonally（from 0.1 and 17% of dissolved Hg（DHg）） with the highest concentrations in summer. DHg diffusive effluxes higher（up to 444 ng/m^2/day） than those reported in the open lagoon（~ 95 ng/m^2/day）, whereas DMeHg showed influxes in the fish farm（up to-156 ng/m^2/day）. The diurnal DHg and DMeHg benthic fluxes were found to be higher than the highest summer values previously reported for the natural lagoon environment. Bottom sediments, especially in anoxic conditions, seem to be a significant source of MeHg in the water column where it eventually accumulates. However, net fluxes considering the daily trend of DHg and DMeHg, indicated possible DMeHg degradation processes. Enhancing water dynamics in the fish farm could mitigate environmental conditions suitable for Hg methylation.

关键词： Mercury Benthic fluxes Biogeochemistry lagoons Sediment–water interface

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合成氨工业催化剂的一种新型前躯体—维氏体

浙江工业大学学报 2004年第2期32卷 123-130页

作者： N. Pernicone F. Ferrero I. Rossetti L. Forni P. Canton P. Riello G. Fagherazzi M. Signoretto F. Pinna Dipartimento di Chimica Fisica ed Elettrochimica Università di MilanoDipartimento di Chimica Fisica ed Elettrochimica Università di MilanoDipartimento di Chimica Fisica Università di VeneziaDipartimento di Chimica Fisica Università di VeneziaDipartimento di Chimica Fisica Università di VeneziaDipartimento di Chimica Università di VeneziaDipartimento di Chimica Università di Venezia Via Pansa 728100 Novara Italy Via Turbigo 2828100 Pernate Novara ItalyVia Golgi 19 20133 Milan ItalyVia Golgi 19 20133 Milan ItalyVia Torino 155b 30170 Venezia Mestre ItalyConsorzio INSTM UDR di Venezia Venezia Italy Via Torino 155b 30170 Venezia Mestre ItalyConsorzio INSTM UDR di Venezia Venezia Italy Via Torino 155b 30170 Venezia Mestre ItalyConsorzio INSTM UDR di Venezia Venezia Italy Dorsoduro 2137 30123 Venezia ItalyConsorzio INSTM UDR di Venezia Venezia Italy Dorsoduro 2137 30123 Venezia ItalyConsorzio INSTM UDR di Venezia Venezia Italy

关于合成氨铁系催化剂最佳氧化态前躯体相矛盾的实验结果推动了当前以维氏体和磁铁矿为母体的催化剂的比较研究。测定了两种催化剂的许多物理性质(密度、孔结构、晶相、还原速率、金属表面、磨耗量)和催化性能(动力学常数、耐热性)。证... 详细信息

关于合成氨铁系催化剂最佳氧化态前躯体相矛盾的实验结果推动了当前以维氏体和磁铁矿为母体的催化剂的比较研究。测定了两种催化剂的许多物理性质(密度、孔结构、晶相、还原速率、金属表面、磨耗量)和催化性能(动力学常数、耐热性)。证明了以维氏体为母体的催化剂具有更高的活性,尤其是在低温下,除了在高转化率情况下之外,可以达到Ru/C催化剂的性能。本文讨论了以维氏体为母体的催化剂具有这种特性的可能原因,并且建议有必要对合成氨铁系催化剂现有统一的理论知识进行重新考虑。

关键词：合成氨工业维氏体催化剂磁铁矿催化剂前躯体动力学常数还原速率

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