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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

FeCl_(3)沉淀法在水溶液中去除药物抗生素的表现

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地球与环境 2023年第1期51卷 117-124页

作者：张杰 Khan M.G.Mostofa Nicola Senesi Giorgio S.Senesi 李思亮天津大学表层地球系统科学研究院天津300072 天津市“环渤海地球关键带科学与可持续发展”重点实验室天津300072 Dip.to di Scienze del Suolo della Pianta e degli AlimentiUniversita degli Studi di Bari"Aldo Moro"Via G.Amendola 165/ABariItaly 70126 cnr-istituto per la Scienza e Tecnologia dei Plasmi(ISTP)-sedediBariViaAmendola 122/DBariItaly70126 海河可持续化学转化实验室天津300192

药物抗生素(PA)残留物普遍存在于土壤和水环境中;因受去除效率及可产生致癌副产物的制约,目前的生物或光化学降解方法难以有效去除PA,且金属离子与PA的吸附/络合机制尚不清楚。本文用FeCl_(3)从水溶液中去除两种PA—盐酸左氧氟沙星(LH)... 详细信息

药物抗生素(PA)残留物普遍存在于土壤和水环境中;因受去除效率及可产生致癌副产物的制约,目前的生物或光化学降解方法难以有效去除PA,且金属离子与PA的吸附/络合机制尚不清楚。本文用FeCl_(3)从水溶液中去除两种PA—盐酸左氧氟沙星(LH)和盐酸坦索罗辛(TH);发现pH=7.5~8.5时,铁以Fe-PA沉淀物(Fe-PAp)形式将PA从水溶液中分离;连续沉淀5次后,90.3%的LH和87.5%TH被去除;分析LH、TH和Fe-PAp的波峰特征,发现:1)LH和TH主要红外峰:3 433和3 329 cm^(-1)(羧酸OH和NH2)、1 676 cm^(-1)(-COO-)、1 467 cm^(-1)(脂肪族C-H)和1 022 cm^(-1)(-S=O),2)Fe-PAp中前述红外峰强度下降或完全消失。通过化学键分析表明:在Fe-PAp形成过程中,电子从PA内各种官能团转移到Fe3+的空d轨道,形成π-d电子键系统。FeCl_(3)应用广泛:1)作为一种高效且有应用前景的无机吸附剂,能够从水中去除PA,可实现大规模分离生活和工业废水中的有机污染物;2)Fe-PAp的形成表明金属-有机复合物可以在碱性土壤和水中长期稳定,解释了Fe-DOM复合物在环境中的长期稳定/固存机制。

关键词：药物抗生素盐酸左氧氟沙星盐酸坦索罗辛氯化铁

Passively Q-switched femtosecond-laser-written thulium waveguide laser based on evanescent field interaction with carbon nanotubes

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Photonics Research 2018年第10期6卷 971-980页

作者： ESROM KIFLE PAVEL LOIKO JAVIER RODRíGUEZ VáZQUEZ DE ALDANA CAROLINA ROMERO AIRáN RóDENAS SUN YUNG CHOI JI EUN BAE FABIAN ROTERMUND VIKTOR ZAKHAROV ANDREY VENIAMINOV MAGDALENA AGUILó FRANCESC DíAZ UWE GRIEBNER VALENTIN PETROV XAVIER MATEOS Universitat Rovira i Virgili Departament Quimica Fisica i Inorgànica Fisica i Cristal·lografia de Materials i Nanomaterials (FiCMA-FiCNA)-EMaS Campus Sescelades E-43007 Tarragona Spain ITMO University 49 Kronverkskiy pr. 197101 St. Petersburg Russia Aplicaciones del Láser y Fotónica University of Salamanca 37008 Salamanca Spain istituto di Fotonica e Nanotecnologie Consiglio Nazionale delle Ricerche (IFN-CNR) Piazza Leonardo da Vinci 32 20133 Milano Italy Department of Physics KAIST 291 Daehak-ro Yuseong-gu 34141 Daejeon South Korea Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy Max-Bom-Str. 2a D-12489 Berlin Germany

Surface channel waveguides(WGs) were fabricated in a monoclinic Tm^(3+):KLu(WO_4)_2 crystal by femtosecond direct laser writing(fs-DLW). The WGs consisted of a half-ring cladding with diameters of 50 and 60 μm located just beneath the crystal surface. They were characterized by confocal laser microscopy and μ-Raman spectroscopy,indicating a reduced crystallinity and stress-induced birefringence of the WG cladding. In continuous-wave(CW)mode, under Ti:sapphire laser pumping at 802 nm, the maximum output power reached 171.1 mW at 1847.4 nm,corresponding to a slope efficiency η of 37.8% for the 60 μm diameter WG. The WG propagation loss was0.7 0.3 d B∕cm. The top surface of the WGs was spin-coated by a polymethyl methacrylate film containing randomly oriented(spaghetti-like) arc-discharge single-walled carbon nanotubes serving as a saturable absorber based on evanescent field coupling. Stable passively Q-switched(PQS) operation was achieved. The PQS60 μm diameter WG laser generated a record output power of 150 m W at 1846.8 nm with η = 34.6%. The conversion efficiency with respect to the CW mode was 87.6%. The best pulse characteristics(energy/duration)were 105.6 nJ/98 ns at a repetition rate of 1.42 MHz.

关键词：激光技术波导技术发展现状通讯技术

A PARALLEL APPROACH FOR IMPLEMENTING GENETIC ALGORITHMS

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A PARALLEL APPROACH FOR IMPLEMENTING GENETIC ALGORITHMS

Neutron Imaging by Boric Acid

IJCNN International Joint Conference on Neural Networks

作者： I.De Falco R.del Balio E.Tarantino R.Vaccaro istituto per la Ricerca sui Sistemi Informatici Paralleli（IRSIP）-cnr Via P.Castellino 11180128Naples（ITALY）

＜正＞Many methods have been proposed for the solution of optimization problems.A great deal of research is currently underway in investigating parallel genetic optimization methods.A basic question of such research is to establish whether a high diffusion process of good local minima among subpopulations can be used effectively as a technique for improving performance of Genetic *** this aim,in this paper,the structure of a defined Parallel Genetic Algorithm has been mapped onto a reconfigurable microcomputer array whose processors have been configured both in a ring and in a chordal-ring *** Parallel Genetic Algorithm has been applied,specifically,to the Travelling Salesman *** results achieved are shown and compared;they prove that high improvement in performance can be obtained by exploiting a high local density diffusion process.

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Detection 2013年第2期1卷 30-35页

作者： Fabio Cardone Giovanni Cherubini Walter Perconti Andrea Petrucci Alberto Rosada ARPA Radiation Laboratories Via Montezebio Viterbo Italy GNFM Istituto Nazionale di Alta Matematica “F. Severi” Città Universitaria Roma Italy Italian National Agency for New Technologies Energy and Sustainable Economic Development (ENEA) Roma Italy istituto per lo Studio dei Materiali Nanostrutturati (ISMN-cnr) Via dei Taurini Roma Italy GNFM Istituto Nazionale di Alta Matematica “F. Severi” Città Universitaria Roma Italy istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA) Roma Italy Unità Tecnica Tecnologie e Impianti per la Fissione e la Gestione del Materiale Nucleare (UTFISST) Laboratorio Caratterizzazione Materiali Nucleari (CATNUC) Italian National Agency for New Technologies Energy and Sustainable Economic Development (ENEA) Roma Italy

In this paper a new type of passive neutron detector based on the already existing one, CR39, is described. Its operation was verified by three different neutron sources: an Americium-Beryllium (Am241-Be) source;a TRIGA type nuclear reactor;and a fast neutron reactor called TAPIRO. The obtained results, reported here, positively confirm its operation and the accountability of the new developed detecting technique.

关键词： Neutrons Neutron Passive Detectors Boron Photographic Film PADC Nuclear Track Detectors (CR39) Neutron Spectrometer

Effect of Yb^(3+) concentration on Er^(3+) luminescence properties of sol-gelderived silica-alumina xerogels

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Optoelectronics Letters 2006年第5期2卷 354-357页

作者： K.Tran Ngoc H.Pham Thanh C.Nguyen Duc C.Armellini A.Chiasera M.Ferrari Y.Jestin M.Montagna E.Moser S.Pelli G.C.Righini cnr-IFN istituto di Fotonica e Nanotecnologie CSMFO groupvia Sommarie 14I-38050 PovoTrentoItaly ITIMS-Hanoi University of Technology No 1Dai Co VietHanoiVietnam Dipartimento di Fisica Università di TrentoCSMFO groupvia Sommarive 14I-38050 PovoTrentoItaly cnr-IFAC Nello Carrara Institute of Applied Physics Lab.of Optoelectronic TechnologiesVia Madonna del Piano 1050019 Sesto FiorentinoFirenzeItaly

Er3+/Yb3+ co-doped silica-alumina monolithic xerogels were prepared with the same concentration on 2 000 Er/Si ppm and 6 000 Al/Si *** Yb/Si content was varied from 0 to 4 000 *** of the samples was achieved by thermal treatment in air at 950 ℃ for 120 hours with a heating rate 0.1 ℃/*** spectroscopy was used to obtain information about the effective excitation efficiency of Er3+ ions by co-doping with Yb 3+ *** infrared-to-visible up-conversion luminescence has been investigated upon continuous wave excitation at 980 *** samples exhibit red,green and blue up-conversion *** is found that the intensity of up-conversion luminescence increases with increasing Yb3+ doping *** opposite behavior is observed for the 4I13/2 luminescence of the Er3+ ions.

关键词：铒离子二氧化硅干凝胶光致发光

Fluorescein derivatives potentiate CFTR by altering the ATP affinity and efficacy of channel gating

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Fluorescein derivatives potentiate CFTR by altering the ATP ...

THE X-RAY AFTERGLOW OF THE GAMMA-RAY BURST OF 1997 MAY 8:SPECTRAL VARIABILITY AND POSSIBLE EVIDENCE OF AN IRON LINE

2008北京国际生理科学学术大会

作者： MORAN Oscar SHEPPARD David N istituto di Biofisica CNRVia DeMarini 616149 GenoaItaly Department of Physiology and Pharmacology University of BristolBristolBS8 1TDUK

The fluorescein derivative phloxine B is a potent modulator of the cystic fibrosis transmembrane conductance regulator(CFTR)Cl *** micromolar concentrations of phloxine B potentiate ATP-dependent channel gating,whereas higher concentrations occlude the channel *** determine whether fluorescein derivatives (FDs)affect the ATP affinity of CFTR and the efficacy of channel gating,we investigated the effects of FDs on the gating behaviour of CFTR using excised inside-out membrane patches from C127 cells expressing wild-type human *** employed a simple linear three-state scheme(C(?)C(?)O)to describe CFTR channel *** this scheme,C represents the long duration closed state separating channel openings,C the brief closures that interrupt channel openings,and O the open *** between the three states are described by the forward rate constantsβ,β and the backward rate constantsα andα.Given that CFTR is an agonist-activated channel gated by intracellular ATP and this scheme is reminiscent of the del Castillo-Katz mechanism,we can calculate the ATP affinity(α/β)and gating efficacy of CFTR(β/α).The FDs phloxine B(1μmol/L)and eosin Y(1μmol/L) augment channel gating by prolonging mean burst duration(MBD)without changing the interburst interval(IBI), whereas dichlorofluorescein(DCF;20μmol/L)decreases the IBI without changing MBD(n=4-15).Interestingly, phloxine B(1μmol/L)and DCF(20μmol/L)decreasedα/β(enhanced affinity),whereas only phloxine B(1μmol/L) elevatedβ/α(augmented gating efficacy).To understand better how FDs affect the relationship between the ATP affinity and gating efficacy,we examined the ATP-dependence of channel gating(n>5).Increasing ATP concentrations enhanced markedly both the ATP affinity and gating efficacy of ***,phloxine B(1μmol/L) augmented both the ATP affinity and gating efficacy of CFTR,particularly at low ATP *** interpret our results to suggest that the ATP affinity and gating efficacy of CFTR are t

关键词： CFTR channel gating ATP affinity gating efficacy

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THE X-RAY AFTERGLOW OF THE GAMMA-RAY BURST OF 1997 MAY 8:SPE...

Strongly enhanced light trapping in a two-dimensional silicon nanowire random fractal array

中国天文学会高能分会2004年学术年会

作者： L.Piro E.Costa M.Feroci F.Frontera L.Amati D.Dal Fiume L.A.Antonelli J.Heise J.in’t Zand A.Owens A.N.Parmar G.Cusumano M.Vietri G.C.Perola istituto Astrofi sica Spaziale Consiglio Nazionale delle Ricerche Via Fosso del Cavaliere 100 00133 Rome Italy istituto Astrofi sica Spaziale Consiglio Nazionale delle Ricerche Via Fosso del Cavaliere 100 00133 Rome Italy istituto Astrofi sica Spaziale Consiglio Nazionale delle Ricerche Via Fosso del Cavaliere 100 00133 Rome Italy istituto Tecnologie e Studio delle Radiazioni Extraterrestri Consiglio Nazionale delle Ricerche Via Gobetti 101 40129 Bologna Italy.Dipartimento di Fisica Universita` Ferrara Via Paradiso 12 Ferrara Italy istituto Tecnologie e Studio delle Radiazioni Extraterrestri Consiglio Nazionale delle Ricerche Via Gobetti 101 40129 Bologna Italy istituto Tecnologie e Studio delle Radiazioni Extraterrestri Consiglio Nazionale delle Ricerche Via Gobetti 101 40129 Bologna Italy BeppoSAX Scienti?c Data Center present address: Osservatorio Astron-omico di Roma Space Research Organization in the Netherlands Sorbonnelaan 2 3584 CA Utrecht Netherlands Space Research Organization in the Netherlands Sorbonnelaan 2 3584 CA Utrecht Netherlands Space Science Department of ESA European Space Research and Tech- nology Centre 2200 AG Noordwijk Netherlands Space Science Department of ESA European Space Research and Tech- nology Centre 2200 AG Noordwijk Netherlands istituto Fisica Cosmica e applicazioni calcolo Informatico Consiglio Nazionale delle Ricerche Via La Malfa 153 90138 Palermo Italy Dipartimento di Fisica Universit Roma Tre Via della Vasca Navale 84 00146 Roma Italy Dipartimento di Fisica Universit Roma Tre Via della Vasca Navale 84 00146 Roma Italy

We report the possible detection (99.3% of statistical signi?cance) of redshifted iron line emission in the X-ray afterglow of gamma-ray burst GRB 970508 observed by BeppoSAX. Its energy is consisten

关键词： gamma rays: bursts — line: formation — X-rays: general

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Light(Science & Applications) 2016年第1期5卷 855-861页

作者： Barbara Fazio Pietro Artoni Maria Antonia Iatì Cristiano D’Andrea Maria JosèLo Faro Salvatore del Sorbo Stefano Pirotta Pietro Giuseppe Gucciardi Paolo Musumeci Cirino Salvatore Vasi Rosalba Saija Matteo Galli Francesco Priolo Alessia Irrera cnr-IPCF Istituto per i Processi Chimico Fisici98158 MessinaItaly Dipartimento di Fisica e Astronomia Universitàdi Catania95123 CataniaItaly cnr-MATIS IMM Istituto per la Microelettronica e Microsistemi95123 CataniaItaly Dipartimento di Fisica Universitàdegli Studi di Pavia27100 PaviaItaly Dipartimento di Scienze Matematiche e Informatiche Scienze Fisiche e Scienze della TerraUniversitàdi Messina98166 MessinaItaly Scuola Superiore di Catania Universitàdi Cataniavia Valdisavoia995123 CataniaItaly

We report on the unconventional optical properties exhibited by a two-dimensional array of thin Si nanowires arranged in a random fractal geometry and fabricated using an inexpensive,fast and maskless process compatible with Si *** structure allows for a high light-trapping efficiency across the entire visible range,attaining total reflectance values as low as 0.1%when the wavelength in the medium matches the length scale of maximum heterogeneity in the *** show that the random fractal structure of our nanowire array is responsible for a strong in-plane multiple scattering,which is related to the material refractive index fluctuations and leads to a greatly enhanced Raman scattering and a bright *** strong emissions are correlated on all length scales according to the refractive index *** relevance and the perspectives of the reported results are discussed as promising for Si-based photovoltaic and photonic applications.

关键词： light trapping multiple scattering Raman enhancement random fractal silicon nanowires