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Big data of online product purchases is an emerging source for obtaining customers’ preferences of product features for new product development. This paper proposes a framework and associated method for product features characterization and customers’ preference prediction based on online product purchase data. Specifications and components of products are firstly analyzed and the relationships between product specifications and components are then established for features characterization. The customers preferred specifications, features and their combinations are predicted for development of new products. The features characterization and customers’ preferences prediction of toy cars were used as an example of illustrating the proposed method. 相似文献
253.
Alberto Paleari Sergio Brovelli Roberto Lorenzi Marco Giussani Alessandro Lauria Natalia Mochenova Norberto Chiodini 《Advanced functional materials》2010,20(20):3511-3518
The design of nanostructured materials with specific physical properties is generally pursued by tuning nanoparticle size, concentration, or surface passivation. An important step forward is to realize “active” systems where nanoparticles are vehicles for controlling, in situ, some specific, tuneable features of a responsive functional material. In this perspective, this work focuses on the rational design of a nanostructured glass with electrically tuneable dielectric function obtained by injection and accumulation of charge on embedded conductive nanocrystals. This enables electrically controlled switching of semiconducting nanophases to charged polarisable states to be achieved, which could lead to smart, field‐enhancement applications in nanophotonics and plasmonics. Here, it is shown that such response switching can be obtained if a percolating charge‐transport mechanism is activated through a disordered tree‐like network, as is demonstrated to be possible in SiO2 films where suitable dispersions of SnO2 nanocrystals, with conductive interfaces, are obtained as a result of a new synthesis strategy. 相似文献
254.
Alessandro Zaggia Gennifer Padoan Lino Conte 《Journal of surfactants and detergents》2010,13(4):409-415
A series of perfluoroalkylated oligo(oxyethylene) glycols as non-ionic fluorinated surfactants was prepared. The synthesis was performed by adding a molecule of a oligo(oxyethylene)glycol of the general formula HO(CH2CH2O)nOH (n = 1, 2, 4, 6.4, 22.3) to 2-(perfluorooctylmethyl) oxirane in the presence of catalytic amounts of a Lewis acid. This procedure led to the formation of an amphiphilic molecule characterized by an hydrophobic lipophobic perfluorinated tail and hydrophilic non-ionic oligo(oxyethylene)chain. Infra red spectroscopy, mass spectroscopy and multinuclear NMR spectroscopy allowed the chemical characterization of the synthesized compounds to be made. Critical micellar concentration, surface tension, interfacial tension and cloud point measurements carries out on aqueous solutions allowed us to evaluate the surface and interfacial properties of the perfluoroalkylated oligo(oxyethylene)glycols. In addition, surface pressure-area (π, A) diagrams allowed us to determine the principal parameters characterizing the state of their monolayers. The aim of the work was to investigate the effect of the hydrophilic chain length on physical and surface properties. 相似文献
255.
Chiara Falciani Dr. Jlenia Brunetti Dr. Chiara Pagliuca Dr. Stefano Menichetti Prof. Lucia Vitellozzi Barbara Lelli Dr. Alessandro Pini Dr. Luisa Bracci Prof. 《ChemMedChem》2010,5(4):567-574
The use of peptide receptors as targets for tumor‐selective therapies was envisaged years ago with the findings that receptors for different endogenous regulatory peptides are overexpressed in several primary and metastatic human tumors, and can be used as tumor antigens. Branched peptides can retain or even increase, through multivalent binding, the biological activity of a peptide and are very resistant to proteolysis, thus having a markedly higher in vivo activity compared with the corresponding monomeric peptides. Oligo‐branched peptides, containing the human regulatory peptide neurotensin (NT) sequence, have been used as tumor‐specific targeting agents. These peptides are able to selectively and specifically deliver effector units, for cell imaging or killing, to tumor cells that overexpress NT receptors. Results obtained with branched NT conjugated to different functional units for tumor imaging and therapy indicate that branched peptides are promising novel multifunctional targeting molecules. This study is focused on the role of the releasing pattern of drug‐conjugated branched NT peptides. We present results obtained with oligo‐branched neurotensin peptides conjugated to 6‐mercaptopurin (6‐MP), combretastain A‐4 (CA4) and monastrol (MON). Drugs were conjugated to oligo‐branched neurotensin through different linkers, and the mode‐of‐release, together with cytotoxicity, was studied in different human cancer cell lines. The results show that branched peptides are very promising pharmacodelivery options. Among our drug‐armed branched peptides, NT4–CA4 was identified as a candidate for further development and evaluation in preclinical pharmacokinetic and pharmacodynamic studies. This peptide–drug exhibits significant activity against pancreas and prostate human cancer cells. Consequently, this derivative is of considerable interest due to the high mortality rates of pancreas neuroendocrine tumors and the high incidence of prostate cancer. 相似文献
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257.
Adriano Fagali de Souza Anselmo Eduardo Diniz Alessandro Roger Rodrigues Reginaldo Teixeira Coelho 《The International Journal of Advanced Manufacturing Technology》2014,71(9-12):1565-1577
This paper presents an investigation of nonplanar tool-workpiece interactions in free-form milling using a ball-end cutting tool, a technique that is widely applied in the manufacturing of dies and molds. The influence of the cutting speed on the cutting forces, surface quality of the workpiece, and chip formation was evaluated by considering the specific alterations of the contact between tool-surface along the cutting time. A trigonometric equation was developed for identifying the tool-workpiece contact along the toolpath and the point where the tool tip leaves the contact with the workpiece. The experimental validation was carried out in a machining center using a carbide ball-end cutting tool and a workpiece of AISI P20 steel. The experimental results demonstrated the negative effect of the engagement of the tool tip into the cut on machining performance. The length of this engagement depends on the tool and workpiece curvature radii and stock material. When the tool tip center is in the cut region, the material is removed by shearing together with plastic deformation. Such conditions increase the cutting force and surface roughness and lead to an unstable machining process, what was also confirmed by the chips collected. 相似文献
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259.
Characterization of a Combined Treatment with Alpha‐Lipoic Acid for the Control of Enzymatic Browning in Fresh‐Cut Golden Delicious Apples
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