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21.
Dr. Sébastien Lemouzy Florian Cuminet Dimitri Berne Dr. Sylvain Caillol Dr. Vincent Ladmiral Prof. Rinaldo Poli Dr. Eric Leclerc 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(48):e202201135
Vitrimers are a third class of polymers gathering the mechanical properties and solvent resistance of 3D thermosets and the reprocessability of thermoplastics. This unique behaviour is due to the triggering of certain covalent exchange reactions that allow the network to rearrange upon application of a stimulus. The constitutive feature of vitrimers is the adoption of a glass-like viscosity during the rearrangement of the network, often due to an associative mechanism for the exchange reaction. Transesterification networks are one of the most studied type of vitrimers that usually require the incorporation of a catalyst, implying the associated drawbacks. Following up on a recent report on catalyst-free transesterification vitrimers in which the ester functions are particularly reactive thanks to the presence of fluorine atoms in α- or β-position, parallel DFT calculations and an experimental kinetic study on model molecules are presented in order to quantitatively assess the effect of neighbouring fluorinated groups on the transesterification reaction rate. 相似文献
22.
Foroni M Passaro D Poli F Cucinotta A Selleri S Laegsgaard J Bjarklev A 《Optics letters》2007,32(21):3164-3166
The influence of each cross-section geometric parameter on hollow-core Bragg fiber guiding properties has been numerically investigated. Fabricated fibers have been modeled, giving insight into the spectral behavior of the confinement loss. It has been verified that, by changing the amount of silica and air in the fiber cladding, it is possible to change the reflection conditions undergone by the field within the core, thus shifting the confinement loss spectrum. 相似文献
23.
M. Poli D. Petroni A. Berton E. Campani C. Felicini S. Pardini L. Menichetti P. A. Salvadori 《Accreditation and quality assurance》2014,19(5):343-354
The last decade has seen extraordinary growth in the clinical use of Positron Emission Tomography (PET), an in vivo molecular imaging modality widely used in oncology that requires the use of radiopharmaceuticals labeled with short-lived radionuclides. These medicinal products have found widespread application in Nuclear Medicine departments equipped with PET scanners. Due to the great increase in radiopharmaceutical demand, their production has been centralized and moved to industrial manufacturing sites in which Good Manufacturing Practice (GMP) principles and guidelines for medicinal products are to be applied. The production of PET radiopharmaceuticals features particular aspects such as the use of the lot before the completion of all tests, the multiplicity of batches produced per single day and the absence of product stock due to radionuclide short half-life. In this context, the application of quality principles to all stages of the process and the implementation of a quality management system (QMS) are of primary importance. This paper reports on the development of a QMS applied to a GMP manufacturing site of an in vivo PET diagnostic product, and on how its application can describe the performance of the site. Data were collected over a 6-year period (2008–2013) and demonstrate the ability of Key Performance Indicators, strictly related to the structure and organization of the QMS, and quality tools (data analysis, internal audit, etc.) to monitor process performance in terms of effectiveness, efficacy and stability. 相似文献
24.
Dr. Yong Wang Yajun Zhao Shuaishuai Zhu Prof. Dr. Xingping Zhou Prof. Dr. Jing Xu Prof. Dr. Xiaolin Xie Prof. Dr. Rinaldo Poli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6044-6050
A strategy that uses carbon monoxide (CO) as a molecular trigger to switch the polymerization mechanism of a cobalt Salen complex [salen=(R,R)-N,N′-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamine] from ring-opening copolymerization (ROCOP) of epoxides/anhydrides to organometallic mediated controlled radical polymerization (OMRP) of acrylates is described. The key phenomenon is a rapid and quantitative insertion of CO into the Co−O bond, allowing for in situ transformation of the ROCOP active species (Salen)CoIII-OR into the OMRP photoinitiator (Salen)CoIII-CO2R. The proposed mechanism, which involves CO coordination to (Salen)CoIII-OR and subsequent intramolecular rearrangement via migratory insertion has been rationalized by DFT calculations. Regulated by both CO and visible light, on-demand sequence control can be achieved for the one-pot synthesis of polyester-b-polyacrylate diblock copolymers (Đ<1.15). 相似文献
25.
Yong Wang Yajun Zhao Shuaishuai Zhu Xingping Zhou Jing Xu Xiaolin Xie Rinaldo Poli 《Angewandte Chemie (International ed. in English)》2020,59(15):5988-5994
A strategy that uses carbon monoxide (CO) as a molecular trigger to switch the polymerization mechanism of a cobalt Salen complex [salen=(R,R)‐N,N′‐bis(3,5‐di‐tert‐butylsalicylidene)‐1,2‐cyclohexanediamine] from ring‐opening copolymerization (ROCOP) of epoxides/anhydrides to organometallic mediated controlled radical polymerization (OMRP) of acrylates is described. The key phenomenon is a rapid and quantitative insertion of CO into the Co?O bond, allowing for in situ transformation of the ROCOP active species (Salen)CoIII‐OR into the OMRP photoinitiator (Salen)CoIII‐CO2R. The proposed mechanism, which involves CO coordination to (Salen)CoIII‐OR and subsequent intramolecular rearrangement via migratory insertion has been rationalized by DFT calculations. Regulated by both CO and visible light, on‐demand sequence control can be achieved for the one‐pot synthesis of polyester‐b‐polyacrylate diblock copolymers (?<1.15). 相似文献
26.
D. Petroni M. Poli L. Campisi P. A. Salvadori L. Menichetti 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(3):757-762
Positron Emission Tomography has become increasingly relevant in clinical practice for diagnostic purposes. A major concern regarding radiopharmaceuticals in general is how quality requirements can be guaranteed in nuclear medicine departments or in cases where marketing authorization has been granted. This article focuses on issues related to the small-volume preparation of radiopharmaceuticals by a Research Institute after Good Manufacturing Practice implementation. 相似文献
27.
28.
S. Torilov S. Thummerer W. von Oertzen Tz Kokalova G. de Angelis H. G. Bohlen A. Tumino M. Axiotis E. Farnea N. Marginean T. Martinez D. R. Napoli M. De Poli S. M. Lenzi C. Ur M. Rousseau P. Papka 《The European Physical Journal A - Hadrons and Nuclei》2004,19(3):307-317
We have studied the reactions
as well as the binary channel
, in order to search for deformed states, which form rotational bands in 40Ca. We observe positive- and negative-parity bands. The negative-parity band is proposed to be a partner of an inversion doublet with the positive-parity states being based on 4p-4h configurations. The properties of the positive-parity states are discussed on the basis of the shell model and the parity doublet on the basis of a cluster model with intrinsic reflection asymmetric shapes.Received: 2 May 2003, Revised: 23 September 2003, Published online: 20 January 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.60.Gx Cluster models 相似文献
29.
30.
D. Sohler Zs. Dombrádi J. Blomqvist J. Cederkäll J. Huijnen M. Lipoglavšek M. Palacz A. Atac C. Fahlander H. Grawe A. Johnson A. Kerek W. Klamra J. Kownacki A. Likar L.-O. Norlin J. Nyberg J. Persson D. Seweryniak G. de Angelis P. Bednarczyk D. Foltescu D. Jerrestam S. Juutinen E. Mäkelä M. de Poli H.A. Roth T. Shizuma Ö. Skeppstedt G. Sletten J. Timár S. Törmänen M. Weiszflog 《The European Physical Journal A - Hadrons and Nuclei》2003,16(2):171-175
Excited states of 99Ag were populated via the 50Cr + 58Ni (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction
channel separation. On the basis of the measured γγ-coincidence relations and angular distribution ratios a significantly
extended level scheme has been constructed up to E
x ∼ 7.8 MeV and I = 35/2. The experimental results were described within the framework of the shell model. Candidates for states fully aligned
in the πg
9/2
-3ν(d
5/2, g
7/2)2 valence configuration space were found at 4109 and 6265 keV.
Received: 18 June 2002 / Accepted: 11 October 2002 / Published online: 4 February 2003
RID="a"
ID="a"e-mail: sohler@atomki.hu
Communicated by J. ?yst? 相似文献