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131.
Raman Scattering Mapping: Sensitive and Reproducible Immunoassay of Multiple Mycotoxins Using Surface‐Enhanced Raman Scattering Mapping on 3D Plasmonic Nanopillar Arrays (Small 39/2018) 下载免费PDF全文
132.
Polymerization processes are probably the most relevant example of a chemical reaction activated by catalysts or radical initiators. Among polymers, polyethylene is by far the most common and largely produced. Here we present a high-pressure synthesis of high-density crystalline polyethylene by using only physical tools such as pressure and light. Low-density polyethylene is obtained by compressing ethylene at room temperature above 3 GPa in the ordered crystal phase, and a highly crystalline polymer is produced in the fluid phase at pressures lower than 1 GPa by using continuous-wave laser lines (lambda < or = 460 nm) as an optical catalyst. The photo-activation is based on a two-photon absorption process to pi* antibonding states, where the change in molecular geometry favours the polymeric chain formation. The high yield and crystallinity of the polymer recovered by the photoinduced reaction and the simplicity of the synthesis make this process appealing for large-scale applications. 相似文献
133.
Coccoli V Luciani A Orsi S Guarino V Causa F Netti PA 《Journal of materials science. Materials in medicine》2008,19(4):1703-1711
Drug delivery applications using biodegradable polymeric microspheres are becoming an important means of delivering therapeutic
agents. The aim of this work was to modulate the microporosity of poly(ε-caprolactone) (PCL) microcarriers to control protein
loading capability and release profile. PCL microparticles loaded with BSA (bovine serum albumin) have been de novo synthesized
with double emulsion solvent evaporation technique transferred and adapted for different polymer concentrations (1.7 and 3%
w/v) and stabilizer present in the inner aqueous phase (0.05, 0.5 and 1% w/v). SEM (scanning electron microscope) and CLSM
(confocal laser scanning microscope) analysis map the drug distribution in homogeneously distributed cavities inside the microspheres
with dimensions that can be modulated by varying double emulsion process parameters. The inner structure of BSA-loaded microspheres
is greatly affected by the surfactant concentration in the internal aqueous phase, while a slight influence of polymer concentration
in the oil phase was observed. The surfactant concentration mainly determines microspheres morphology, as well as drug release
kinetics, as confirmed by our in-vitro BSA release study. Moreover, the entrapped protein remained unaltered during the protein
encapsulation process, retaining its bio-activity and structure, as shown through a dedicated gel chromatographic analytical
method. 相似文献
134.
Vincenzo Levis 《Calcolo》1964,1(3-4):299-336
This Note takes again a late work byM. Volpato, which indicates the resolution. with method of dynamics programming, of a non-linear problem in Econometrics, for decide
theoptimum in a buying and selling business. When involved functions are linear, the question becomes aLP problem whose solutions is given from known methods.
Here, subject shows, by method of Volpato, a very easy proceeding involving only comparisons among the dates of question.
Moreover, the result confirms an intuitive rule of Economical Policy which, perhaps for the first time, is strictly justified.
Lavoro eseguito nell'ambito dell'attività del Gruppo di Ricerca n0 38 (Univ. ca' Foscari-Venezia) del Comitato per la matematica del C.N.R. per l'A.A. 1963–64. 相似文献
Lavoro eseguito nell'ambito dell'attività del Gruppo di Ricerca n0 38 (Univ. ca' Foscari-Venezia) del Comitato per la matematica del C.N.R. per l'A.A. 1963–64. 相似文献
135.
Table olive quality depends on a number of factors, including fruit characteristics, ripening and processing technologies. Volatile and semi-volatile organic compounds, present both in the sample matrix and in the headspace aroma, are responsible for the olive fruit flavour influencing the consumer’s preference. 相似文献
136.
In this paper, we report on our experiences of using lightweight formal methods for the partial validation of natural language requirements documents. We describe our approach to checking properties of models obtained by shallow parsing of natural language requirements, and apply it to a case study based on part of a NASA specification of the Node Control Software on the International Space Station. The experience reported supports our position that it is feasible and useful to perform automated analysis of requirements expressed in natural language. Indeed, we identified a number of errors in our case study that were also independently discovered and corrected by NASA's Independent Validation and Verification Facility in a subsequent version of the same document, and others that were not discovered. The paper describes the techniques we used, the errors we found and reflects on the lessons learned. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
137.
Annalisa Dalmoro Anna Angela Barba Marina Lamberti Mina Mazzeo Vincenzo Venditto Gaetano Lamberti 《Journal of Materials Science》2014,49(17):5986-5996
In this work, the degradation phenomena and the release kinetics of an active molecule from matrices systems made of random copolymers of ε-caprolactone (CL) and l-lactide (LA) were investigated by exposing the matrices, shaped as thin films, to simulated physiological environments. α-tocopherol was incorporated into the films as hydrophobic model molecule with the aim to investigate both its release pattern and its effect on erosion phenomena. In particular, the films have been kept at controlled conditions (temperature, stirring, pH) and they were characterized in terms of weight loss, water uptake, thermal properties, and change of number average molecular weight, in order to explain the molecule release kinetics and the degradation pathways of the copolymers. The main findings of this study are that the erosion phenomena take place significantly only when a critical value of the molecular mass was obtained in the sample; that the presence of the drug stabilizes the matrix and it decreases the rate of molecular mass decrease; and that crystallinity, reducing the chain mobility, causes lower erosion rates. 相似文献
138.
Leveraging the Ambipolar Transport in Polymeric Field‐Effect Transistors via Blending with Liquid‐Phase Exfoliated Graphene 下载免费PDF全文
139.
140.
Fortuna Iannuzzo Vincenzo Piccolo Ettore Novellino Elisabetta Schiano Emanuela Salviati Vincenzo Summa Pietro Campiglia Gian Carlo Tenore Maria Maisto 《International journal of molecular sciences》2022,23(21)
Proanthocyanidins (PACs) are a group of bioactive molecules found in a variety of plants and foods. Their bioavailability depends on their molecular size, with monomers and dimers being more bioavailable than those that have a higher polymerization degree. This study aimed to develop a method to convert high-molecular-weight PACs to low-molecular-weight ones in a grape seed extract (GSE) from Vitis vinifera L. Therefore, GSE was subjected to alkaline treatment (ATGSE), and its difference in chemical composition, compared to GSE, was evaluated using a molecular networking (MN) approach based on results obtained from HPLC-ESI HRMS/MS characterization analysis. The network analysis mainly noted the PAC cluster with about 142 PAC compounds identified. In particular, the obtained results showed a higher content of monomeric and dimeric PACs in ATGSE compared to GSE, with 58% and 49% monomers and 31% and 24% dimers, respectively. Conversely, trimeric (9%), polymeric (4%), and galloylated PACs (14%) were more abundant in GSE than in ATGSE (6%, 1%, and 4%, respectively). Moreover, in vitro antioxidant and anti-inflammatory activities were investigated, showing the high beneficial potential of both extracts. In conclusion, ATGSE could represent an innovative natural matrix rich in bioavailable and bioaccessible PACs for nutraceutical applications with potential beneficial properties. 相似文献