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Journal of Intelligent Information Systems - Medical free-text records store a lot of useful information that can be exploited in developing computer-supported medicine. However, extracting the...  相似文献   
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The objective of this study is to establish the corrosion behaviour of the most important structural constituents of the aluminium alloy 2017 in orthophosphoric acid solutions containing heteropolyoxomolybdate, tungstate and vanadate. These are potential candidates for replacing toxic hexavalent chromium species in stripping solution for anodic coatings. The corrosion rate of the alloy is estimated with linear polarisation method. It decreases from 0.58 mA cm−2 in uninhibited solution to 0.10 mA cm−2 in a solution containing heteropolyoxomolybdate species. Microscopic studies reveal that heteropolyoxomolybdate species inhibit corrosion of the matrix and intermetallic Al15(Fe,Mn)3(Si,Cu)2 but not Mg2Si. Intermetallic Al2Cu remains not corroded. Heteropolyoxotungstate species virtually do not inhibit the corrosion of the alloy. The solution containing vanadium species is not stable with time and the corrosion rate is not determined. Nevertheless, corrosion of the matrix is inhibited, but intermetallics Al15(Fe,Mn)3(Si,Cu)2 together with Mg2Si are dissolved. X-ray photoelectron spectroscopy is used for examination of a corrosion product precipitated on the surface.  相似文献   
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The paper presents an influence problem of the rotational flexibility of supporting joints on steel frames behaviour. A substantial part of the paper is devoted to, neglected in the engineering practice, issue of rotational flexibility of the foundation-subgrade system. This problem was analyzed on the assumption that the foundation in the form of a rectangular rigid punch rests on a homogeneous medium of finite depth. Suitable analyses of the foundation were done using several subgrade models: Winkler’s model, elastic half-space (in the classic approach) and with the use of the boundary element method, as well as HS model (hardening soil) by application of the finite elements method. The phenomenon of rotational flexibility of footings resting on a soil subgrade was analyzed within the linear range. It was shown, that the practical assessment of rotational stiffness of footings resting on subgrade can also be performed by using simple methods (e.g., based on the Winkler’s model). The presented evaluation methods of the whole flexibility supported joints were used in the static and stability analyses of the certain steel frame. The presented results confirmed a significant influence of the flexibility of the supporting joints on the steel frames behaviour.  相似文献   
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Nonlinear optical materials are essential in areas such as nanophotonics, optical information processing, and biomedical imaging. However, nanomaterials employed for these diverse applications to date are efficient only for one type of nonlinear optical activity. Herein, the first multimodal nonlinear optically active class of nanomaterials based on lanthanide-doped lithium niobate nanoparticles, which simultaneously exhibit unprecedentedly efficient second and third harmonic generation, as well as up-conversion photoluminescence, is reported. These dielectric nanoparticles retain their high nonlinear optical conversion efficiency both as powder and as aqueous colloidal solution. The high stability also allows for the fabrication of optically active biocompatible micron-sized fibers and polymer-based 3D-printable objects, as well as for fingerprint detection. Finally, the first 8-bit coding platform purely based on multimodal nonlinear optical activity originating from different parametric and nonparametric processes is demonstrated, showcasing the technological potential of these materials for both anti-counterfeiting and advanced optical information processing.  相似文献   
36.
Ganoderma lucidum is an important medicinal mushroom species and there is continuous interest in its bioactive properties. This study evaluated whether it may additionally serve as a nutritional supplement for the trace elements: selenium (Se), copper (Cu), and zinc (Zn). Mushrooms were cultivated on substrates enriched with 0.1 to 0.8 mM of inorganic Se alone or in combination with Zn and/or Cu. Supplementation increased accumulation of the elements in fruiting bodies regardless of the applied cultivation model. G. lucidum demonstrated the ability to accumulate significant amounts of organic Se, maximally amounting to (i) over 44 mg/kg when the substrate was supplemented only with Se, (ii) over 20 mg/kg in the Se+Cu model, (iii) over 25 mg/kg in the Se+Zn model, and (iv) 15 mg/kg in the Se+Cu+Zn model. The accumulation of Cu and Zn steadily increased with their initial substrate concentrations. Maximum concentrations found after supplementation with 0.8 mM amounted to over 55 mg/kg (Se+Zn) and 52 mg/kg (Se+Cu+Zn) of Zn, and 29 mg/kg (Se+Cu) and over 31 mg/kg (Se+Cu+Zn) of Cu. The greater the supplemented concentration and number of supplemented elements, the lower the biomass of G. lucidum fruiting bodies. Nevertheless, it still remained high when the substrate was supplemented up to 0.4 mM with each element. These results highlight that G. lucidum can easily incorporate elements from the substrate and that, when biofortified, its dried fruiting bodies may serve as a nutritional source of these essential elements.  相似文献   
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Coagulation/flocculation (CF) by use of alum and cationic polymer polyDADMAC, was performed as a pretreatment for remediation of oil sands process-affected water (OSPW). Various factors were investigated and the process was optimized to improve efficiency of removal of organic carbon and turbidity. Destabilization of the particles occurred through charge neutralization by adsorption of hydroxide precipitates. Scanning electron microscope images revealed that the resultant flocs were compact. The CF process significantly reduced concentrations of naphthenic acids (NAs) and oxidized NAs by 37 and 86%, respectively, demonstrating the applicability of CF pretreatment to remove a persistent and toxic organic fraction from OSPW. Concentrations of vanadium and barium were decreased by 67-78% and 42-63%, respectively. Analysis of surface functional groups on flocs also confirmed the removal of the NAs compounds. Flocculation with cationic polymer compared to alum, caused toxicity toward the benthic invertebrate, Chironoums dilutus, thus application of the polymer should be limited.  相似文献   
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In the paper, the model of the power supply of the LED lamp in the form dedicated for SPICE is proposed. The form of the worked out by the authors' model is presented, and the results of experimental verification of this model for the LED lamp of the type CLA25 are shown. The presented model is elaborated only for the power supply of LED lamps, in which the constant output voltage is stabilized. This model has the form of a subcircuit for SPICE, and it describes the influence of load resistance, amplitude of the input voltage, and the ambient temperature on both the input current and the output voltage. It is confirmed that the worked out model describes correctly both the waveform of the current received from the electroenergy network and the influence of the load current, the ambient temperature, and the supply voltage on the output voltage.  相似文献   
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The rapid development and expansion of the Internet and the social–based services comprised by the common Web 2.0 idea provokes the creation of the new area of research interests, i.e. social networks on the Internet called also virtual or online communities. Social networks can be either maintained and presented by social networking sites like MySpace, LinkedIn or indirectly extracted from the data about user interaction, activities or achievements such as emails, chats, blogs, homepages connected by hyperlinks, commented photos in multimedia sharing system, etc. A social network is the set of human beings or rather their digital representations that refer to the registered users who are linked by relationships extracted from the data about their activities, common communication or direct links gathered in the internet–based systems. Both digital representations named in the paper internet identities as well as their relationships can be characterized in many different ways. Such diversity yields for building a comprehensive and coherent view onto the concept of internet–based social networks. This survey provides in–depth analysis and classification of social networks existing on the Internet together with studies on selected examples of different virtual communities.  相似文献   
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