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21.
Paola Scarfato Elvira Avallone Pio Iannelli Vincenzo De Feo Domenico Acierno 《应用聚合物科学杂志》2007,105(6):3568-3577
In this paper we report on the preparation and characterization of polyurea‐based microencapsulated systems, containing essential oils as core materials, for potential applications in controlled‐release formulations of agrochemicals. Microcapsules were synthesized by interfacial polymerization in o/w emulsion between polyfunctional isocyanates and diamines, to investigate the effect of the monomer kind on the morphology and properties of the produced samples. The synthetic conditions that gave the best results were used to microencapsulate four essential oils, able to interfere with the seed germination and radicle elongation of some test plants. The produced samples were characterized, with the aim to analyze their morphology and to verify the effectiveness of essential oil microencapsulation. Moreover, preliminary bioassay based on seed germination and subsequent radical growth were carried out to study the effects of the microencapsulated essential oils. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
22.
The process of incorporation of zinc into a copper cathode has been experimentally studied in a molten salt system at 381±2° C and at various current densities. The process is shown to be kinetically controlled by the diffusion of Zn into the solid matrix. A galvanostatic pulse titration technique has been used to determine the chemical diffusion coefficient at various alloy compositions, and an exponential relationship has been found between the diffusivity and the third power of the zinc concentration in the alloy. This relationship was then used in the diffusion equation within the solid matrix and a numerical integration was performed. Very good agreement was found between the calculated and experimental data for Zn interfacial concentration versus time. The same calculation procedure was used to determine zinc concentration profiles in the alloys.Nomenclature
c
A
concentration of the diffusing metal (mol cm–3)
-
D
AB
chemical diffusion coefficient of A into B (cm2 s–1)
-
E
cell e.m.f. (mV)
-
F
Faraday number
-
i
current density (A cm–2)
-
t
time (s)
-
V
M
alloy molar volume (cm3 mol–1)
-
x
linear dimension in the diffusion direction (cm)
-
X
zinc mass fraction in the alloy
-
z
ionic valence of Zn
-
stoichiometric ratio Zn/Cu 相似文献
23.
Using a wetted wall laboratory absorber, the rate of ozone absorption in aqueous phenol solutions has been measured in the pH range 1.75–12.The phenol concentration was varied in a wide range (7–800 ppM) and the ozone partial pressure over a six-fold range. The temperature and the liquidThe results were interpreted by assuming that the rate determining step of a reaction sequence is different in acid and basic solutions. 相似文献
24.
Vincenzo Tufano Roberto Andreozzi Vincenzo Caprio Maria Giovanna D'Amore Amedeo Insola 《臭氧:科学与工程》1994,16(3):181-195
A method for the assessment of the optimal operating conditions for a mechanically stirred gas–liquid reactor is presented. The method exploits both fluid dynamic and chemical information. First, the behavior of the specific stirring power as a function of the stirrer speed allows singling out the dispersion region, in which the most efficient gas–liquid mass transfer is achieved. Inside this region, the analysis of experimental data obtained when considering a chemical system reacting at moderate Hatta numbers (i.e., Ha < about 2) allows determination of the rate constants and the fluid dynamic parameters (i.e., the mass transfer coefficient in the absence of chemical reaction and the characteristic diffusion time). 相似文献
25.
An experimental study was carried out on the ultrafiltration (UF) of protein-containing solutions under different conditions, as compared with a solution of a linear synthetic polymer. Three different fluidynamic regimes were investigated, namely, unstirred batch system, stirred batch system, and recirculating system. The results obtained substantially agree with the predictions of the gel polarization model. A significant effect of the electrolytes on the UF flux has been observed, which can be attributed to solute–solute interaction. The influence of different UF membranes has also been investigated. 相似文献
26.
Binary and m-ary encoding in applications of tree-based genetic algorithms for QoS routing 总被引:1,自引:1,他引:0
Vincenzo Maniscalco Silvana Greco Polito Antonio Intagliata 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2014,18(9):1705-1714
Ubiquitous and Pervasive Computing (UPC) applications often have Quality of Service (QoS) requirements. These become constraints for the UPC network infrastructure. In this paper, we refer to Mobile ad Hoc Networks, one of the most important technologies supporting UPC, and investigate on Genetic Algorithms (GAs) for QoS routing. GAs are part of the soft computing paradigm and can solve the NP search of QoS routes with multiple constraints. We elaborate on tree-based GAs, which represent the set of paths from source to destination as a tree and encode them through the crossed junctions. While their most well-known applications use m-ary encoding representing single paths in the chromosomes, in this paper we discuss a binary encoding with the objective of improving the convergence speed. The binary encoding represents classes of paths in the chromosomes and allows local search on classes of paths. These classes are both collectively exhaustive and mutually exclusive. Simulation results compare convergence speed and scalability of GA applications with binary and m-ary encoding in networks with an increasing number of nodes and links per node. As the per-class processing is reason of additional computational cost, an hybrid GA application that uses both binary and m-ary encoding is introduced. 相似文献
27.
Andrea Ciancone Mauro Luigi Drago Antonio Filieri Vincenzo Grassi Heiko Koziolek Raffaela Mirandola 《Software and Systems Modeling》2014,13(4):1269-1290
Automatic prediction tools play a key role in enabling the application of non-functional requirements analysis, to simplify the selection and the assembly of components for component-based software systems, and in reducing the need for strong mathematical skills for software designers. By exploiting the paradigm of Model-Driven Engineering (MDE), it is possible to automatically transform design models into analytical models, thus enabling formal property verification. MDE is the core paradigm of the KlaperSuite framework presented in this paper, which exploits the KLAPER pivot language to fill the gap between design and analysis of component-based systems for reliability properties. KlaperSuite is a family of tools empowering designers with the ability to capture and analyze quality of service views of their systems, by building a one-click bridge towards a number of established verification instruments. In this article, we concentrate on the reliability-prediction capabilities of KlaperSuite and we evaluate them with respect to several case studies from literature and industry. 相似文献
28.
Anna Galotta Enrico Giust Mauro Bortolotti Gian D. Sorarù Vincenzo M. Sglavo Mattia Biesuz 《Journal of the American Ceramic Society》2021,104(9):4329-4340
Diatomite, a natural silicate-based sedimentary rock, was densified by cold sintering at room temperature and 150°C under various pressures (100, 200, and 300 MPa) and using different NaOH water solutions (0–3 M). The relative density of cold sintered diatomite can be as high as 90%, a condition that can be achieved by conventional firing only at 1200–1300°C. The cold sintered materials maintain the same mineralogical composition of the starting powder (quartz, glass, and illite) and are constituted by well-deformed and flattened grains oriented orthogonally to the applied pressure. Conversely, an evident phase evolution takes place upon conventional firing with the formation of cristobalite and mullite. The bending strength of cold sintered artifacts can exceed 40 MPa and increases to ≈80 MPa after post-annealing at 800°C, such mechanical strength is much larger than that of conventionally pressed samples sintered at 800°C, which is only ≈1 MPa. 相似文献
29.
Ilaria Bartolini Vincenzo Moscato Ruggero G. Pensa Antonio Penta Antonio Picariello Carlo Sansone Maria Luisa Sapino 《Multimedia Tools and Applications》2016,75(7):3813-3842
The valorization and promotion of worldwide Cultural Heritage by the adoption of Information and Communication Technologies represent nowadays some of the most important research issues with a large variety of potential applications. This challenge is particularly perceived in the Italian scenario, where the artistic patrimony is one of the most diverse and rich of the world, able to attract millions of visitors every year to monuments, archaeological sites and museums. In this paper, we present a general recommendation framework able to uniformly manage heterogeneous multimedia data coming from several web repositories and to provide context-aware recommendation techniques supporting intelligent multimedia services for the users—i.e. dynamic visiting paths for a given environment. Specific applications of our system within the cultural heritage domain are proposed by means of real case studies in the mobile environment related both to an outdoor and indoor scenario, together with some results on user’s satisfaction and system accuracy. 相似文献
30.
The aim of this paper is to present the relation between an evolutionary variational inequality with long-term memory and Lagrange multipliers. More precisely, we study the oligopolistic market equilibrium problem in which the profit function depends also on previous events of the market by means of a long-term memory which takes into account the previous states of the equilibrium. Moreover, thanks to the variational formulation, we are able to show existence and regularity results for equilibrium solutions. Then, we apply the infinite dimensional duality theory through which we obtain the existence of Lagrange multipliers which are great utility in order to understand the behaviour of the market. Finally, an example is provided, which allows to analyse the influence of the long-term memory on the equilibrium solution. 相似文献