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31.
Program environments or operating systems generally leave the decision on the allocation of program entities to the developer, offering either placement directives, or tools available through the manipulation of a graphical interface. These approaches cannot always take into account the dynamic behavior of applications, dynamicity in the execution environment or the heterogeneity of the execution platform. Transparent deployment algorithms are necessary for automizing and optimizing application distribution. The Adaptive Distributed Applications in Java (ADAJ) project deals with placement and migration of Java objects. It automatically deploys parallel Java applications on a cluster of workstations using monitoring information about the application behavior. The transparency obtained through the integration of these tools in the middleware makes such an environment easy to use and improves efficiency. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
32.
Violeta Ivanova Marina Stefova Borimir Vojnoski Ágnes Dörnyei László Márk Violeta Dimovska Traj?e Stafilov Ferenc Kilár 《Food research international (Ottawa, Ont.)》2011,44(9):2851-2860
The composition of polyphenols in the skin, seed and pulp extracts of the grapes of Vranec and Smederevka varieties, and Merlot and Chardonnay as well, was analyzed by liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS) and MS/MS techniques. Thirty-one phenolic compounds, including anthocyanins, flavonols and flavan-3-ols, as well as phenolic acids derivatives, have been identified in the extracts prepared from the grapes at physiological maturity, by mass spectrometry applying electrospray ionization operated in alternating ion mode and by performing tandem MS experiments in the ion trap mass analyzer. Grapes were analyzed at three different phases: (i) veraison, (ii) physiological ripeness and (iii) late harvest, in order to follow the evolution of polyphenolic content during berry development, applying spectrophotometric methods. Vranec had a higher polyphenolic content compared to Merlot due to the higher levels of total phenolics and flavonoids in the skins and seeds as well as a higher content of flavan-3-ols and anthocyanins in the skins, allowing discriminating the varieties. HPLC-DAD-MS analysis presented significantly higher relative amounts of anthocyanin monoglucosides and p-coumaroylglucosides in Vranec grapes. Smederevka seeds had a higher amount of flavan-3-ols than Chardonnay, while a higher content of total phenolics and flavonoids was found in the skins of the Chardonnay variety. Anthocyanin content in both red varieties increased during the berry ripening, while flavan-3-ols in seeds were mainly accumulated in the veraison phase followed by decrease of the content with ripening. 相似文献
33.
Igor Tomasevic Margarita Dodevska Milan Simić Smiljana Raicevic Violeta Matovic Ilija Djekic 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):49-53
In total 7351 meat preparations and fresh processed meat products were analysed from 555 different Serbian meat producers over a 10-year period, 4.5 years before and 5.5 years after mandatory Hazard Analysis and Critical Control Points (HACCP) implementation. From the obtained results, it could be concluded that HACCP has contributed to a better alignment of practices with the legal provisions. The share of non-compliant samples dropped from 18.6% before HACCP to 8.3% after its mandatory implementation. Average sulphite concentrations for all categories of meat preparations and fresh processed meat products decreased by 43%, declining from 33.6 to 19.3 mg kg?1. Typical misuse and frequent abuse of sulphites was independent of a season. Application of HACCP principles in the Serbian meat industry raised awareness about the misuse of sulphites and contributed to a better control, minimising exposure to sulphites. 相似文献
34.
Wireless Personal Communications - In this paper, we propose a scheme allow vehicles in a Vehicular Ad hoc Network share running information among them. We developed a mechanism that can help a... 相似文献
35.
Violeta Paşcalău Emoke Pall Mihaela Tertis Maria Suciu Cecilia Cristea Gheorghe Borodi 《国际聚合物材料杂志》2019,68(1-3):60-72
AbstractThe aim of this study is to develop core shell microcapsules of bovine serum albumin (BSA) gel with a complex polyelectrolite multilayer shell of natural polysaccharides with opposite charges, pectin (P), chitosan (Chi), and hyaluronic acid (HA) respectively, encapsulating Doxorubicin (Dox) as a carrier for targeted anti-tumoral treatment of hepatic cell carcinoma (HCC). A sacrificial CaCO3 template method was used in order to obtain microcapsules with a BSA gel core and a layer-by-layer (Lbl) deposition technique of polyelectrolite complexes formed between P/Chi in the inner layers and HA/Chi in the outer shell layers. The preformed microcapsules, BSA gel/P/Chi/HA, noted as ms, have been applied for Dox encapsulation (ms-Dox). Dox encapsulation and release in different pH media were studied in order to elucidate the interactions between pH dependently charged species involved in the Dox loading/releasing processes. The structure characterization of ms/ms-Dox was evaluated by FTIR and UV-Vis spectroscopy, X-ray diffraction, thermal analy sis, optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy. The in vitro study for citotoxicity assessment on normal and tumoral cells of both ms and ms-Dox was performed using mesenchymal stem cells (MSCs) and Hep2G HCC cell lines. Results of physical-chemical analyses confirm the successful encapsulation of Dox in ms, and the in vitro biological study recommends ms-Dox as a candidate for future in vivo research as a targeted anti-tumoral treatment modality applications. 相似文献
36.
Biodegradation of pyridine‐based polyether polyurethanes by the Alternaria tenuissima fungus 下载免费PDF全文
The scope of the present work is to study the biodegradability behavior of several novel heterocyclic poly(ether urethanes) when their hard segments are subjected to exposure to the Alternaria tenuissima fungus. The heterocyclic poly(ether urethanes) were chain‐extended with various pyridine derivatives that had different functional groups placed in different positions on the pyridine rings. Different ratios of the reactive components were also used. The measurements obtained by the use of the attenuated total reflectance–Fourier transform infrared spectroscopy revealed the different structural changes that occurred after exposure to fungi. The degradation process was analyzed through measurement of the mechanical properties and surface morphology evolution by scanning electron microscopy. The obtained results show that the nature and design of the functional groups on the pyridine ring determine the strength of the cohesion linkages that in turn influence different degradation behaviors under exposure to fungi. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46096. 相似文献
37.
Violeta Bokan Bosiljkov 《Cement and Concrete Research》2003,33(9):1279-1286
Nonpozzolanic fillers are frequently used to optimise the particle packing and flow behaviour of cementitious paste in self-compacting concrete (SCC) mixes. This paper deals with the influence of finely ground limestone and crushed limestone dust on the properties of SCC mixes in the fresh and hardened state. Mixes were prepared using poorly graded crushed limestone aggregate. To compensate the lack of fine material in the crushed sand, a viscosity agent (VA) was added to the mixtures. The results obtained indicate that finer and better-graded limestone dust significantly increases the deformability of the paste. When a high volume of this filler was added to the SCC mix, the required self-compacting properties were achieved at a lower water/(cement+filler) ratio, and it also appeared that the addition of filler improves the 28-day compressive strength of concrete mixes due to the filler effect and improved fine-particle packing. 相似文献
38.
The synthesis of a new chelating ion exchanger with hydroxamic and amidoxime groups was performed by an aminolysis reaction of an ethylacrylate/acrylonitrile/divinylbenzene copolymer with hydroxylamine in the presence of sodium ethoxylate. We studied the retention property of the new resin for Pb(II), Cd(II), Cu(II), Ni(II), Zn(II), Mn(II), and Fe(III) metal cations from aqueous solutions. The retention capacity depends on the contact time, the pH of the solution, and the types of counterions of the metal cations. Competitive adsorptions of Pb(NO3)2 + Fe2(SO4)3, Pb(NO3)2 + MnSO4, Pb(NO3)2 + Cd(NO3)2, and Pb(NO3)2 + CuCl2 on the new chelating ion exchanger were performed. The results showed that the resin preferentially retained the Pb(II) ions from the binary aqueous mixtures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2956–2962, 2003 相似文献
39.
Egle Sendzikiene Violeta Makareviciene Prutenis Janulis Dovile Makareviciute 《European Journal of Lipid Science and Technology》2007,109(5):493-497
One of the positive features of biofuel concerning environmental protection is its high biodegradability. Fuel is considered to be biodegradable if not less than 90% of it degrades within 21 days. The aim of this work was to determine the biodegradability of various kinds of fatty acid methyl esters and their mixtures with fossil diesel fuel in natural environments. It was determined that fatty acid methyl esters meet the requirements for biodegradability set by the EU. Of rapeseed oil fatty acid methyl esters (RME), 91.2% degraded within 21 days, compared to 94.2% of rapeseed oil fatty acid ethyl esters, 98.3% of linseed oil fatty acid methyl esters (LSME), 90% of tallow fatty acid methyl esters, and 92.5% of pork lard fatty acid methyl esters (LME), while the amount of degraded fossil diesel fuel reached only 57.3%. The biodegradability of multi‐component biofuels containing RME, LSME and LME is similar; the best is of a mixture of 70% RME, 6% LSME and 24% LME. It was determined that more than 90% of multi‐component biofuel and fossil diesel fuel mixtures degrade within 21 days when they contain 35% and more of multi‐component biofuel. 相似文献
40.