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1.
The potentiodynamic anodic behavior of zinc, nickel, and their alloy is studied depending on the compositions of both the electrolyte for dissolution and electroplates to be dissolved. Zinc deposits are indifferent to the presence of chloride ions in solutions. However, the latter ions strongly affect the anodic behavior of Ni and Zn–Ni alloy. The curves of increasing the polarization of the alloys containing more than 70% Ni demonstrate peaks corresponding to the dissolution of both the Zn–Ni solid solution in a range from –0.2 to +0.2 V and nickel in a range from 0.6 to 0.9 V. For alloys containing less than 31% Ni, no peak of its anodic dissolution is observed, because all Ni is bound with Zn.  相似文献   
2.
In this study, a series of donor–acceptor–donor (D-A-D) type small molecules based on the fluorene and diphenylethenyl enamine units, which are distinguished by different acceptors, as holetransporting materials (HTMs) for perovskite solar cells is presented. The incorporation of the malononitrile acceptor units is found to be beneficial for not only carrier transportation but also defects passivation via Pb–N interactions. The highest power conversion efficiency of over 22% is achieved on cells based on V1359, which is higher than that of spiro-OMeTAD under identical conditions. This st shows that HTMs prepared via simplified synthetic routes are not only a low-cost alternative to spiro-OMeTAD but also outperform in efficiency and stability state-of-art materials obtained via expensive cross-coupling methods.  相似文献   
3.
The paper reflects on the unique experience of social and technological development in Lithuania since the regaining of independence as a newly reshaped society constructing a distinctive competitive IST-based model at global level. This has presented Lithuanian pattern of how to integrate different experiences and relations between generations in implementing complex information society approaches. The resulting programme in general is linked to the Lisbon objectives of the European Union. The experience of transitional countries in Europe, each different but facing some common problems, may be useful to developing countries in Africa.
Arunas Augustinaitis (Corresponding author)Email:
Richard EnnalsEmail:
Egle MalinauskieneEmail:
Rimantas PetrauskasEmail:
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5.
BACKGROUND: Carbazole derivatives are well known to exhibit interesting electro‐ and photo‐active properties due to their hole‐transporting ability, strong absorption in the ultraviolet spectral region and blue‐light emission. One of the most widely studied materials among carbazole‐containing oligomers is poly[9‐(2,3‐epoxypropyl)carbazole] (PEPK). The main field of application of this oligomer is electrophotographic microfilming. It is also used for the manufacture of multicolour slides and in the photothermoplastic recording of information. Unfortunately, due to its high ionization potential, which reaches 5.86 eV, the possibilities of application of this compound in optoelectronic devices are rather limited. RESULTS: PEPK‐based charge transporting oligomers, incorporating hydrazone moieties, are reported. The oligomers were prepared by chemical modification of PEPK. The materials obtained were examined using various techniques including differential scanning calorimetry and ultraviolet, infrared and NMR spectroscopy. Electron photoemission spectra of layers of the synthesized oligomers showed ionization potentials (Ip) in the range 5.4–5.5 eV. CONCLUSION: The synthesized oligomers possess a larger π‐conjugated system and show ionization potentials of ca 5.4 eV. Therefore, they are more suitable for use in optoelectronic devices with quicker photoresponse than unmodified PEPK. Copyright © 2008 Society of Chemical Industry  相似文献   
6.
The purpose of intelligent built environment is to improve inhabitant's quality of life and to satisfy inhabitants by replacing routine work with smart devices and robots. Smart devices and robots can interpret changes in the built environment and respond appropriately. The problem is how to define a rational intelligent built environment when many various stakeholders are involved, projects have thousands of alternative versions and the quality of life and economical efficiency changes with alterations in micro and macro environmental conditions and the constituent parts of the process in question. Moreover, the realization of some objectives seems more rational from the economic perspective though their significance is varied from other perspectives. The formalized Model for Complex Analysis of Intelligent Built Environment and the Multiple Criteria Decision Support System of Intelligent Built Environment developed by the authors of this paper show how changes in project alternatives and the extent to which the goals of various stakeholders are satisfied cause respective changes in the value and utility degree of a project. To achieve the above-mentioned aims new multiple criteria analysis methods were developed.  相似文献   
7.
At concentrations up to 6.7 ppm, 8-methoxypsoralen, sphondin, and khellin are not toxic to first-instar larvae of the mosquitoAedes aegypti. The irradiation of sensitized larvae with long-wavelength ultraviolet light did not always produce any immediate toxicity enhancement, but delayed effects were clearly visible. These were observed over the development of the organisms from first-instar larvae to adults. No adverse effects were noted when larvae were irradiated in the absence of sensitizers, or when they were placed in solutions of sensitizers which had been previously irradiated with the same light sources. 8-Methoxypsoralen was slightly more phototoxic than its isomer sphondin. Khellin, recently reported to undergo photoinduced cyclization with DNA components, showed minimal phototoxicity in the concentration range used.  相似文献   
8.
Alpha-terthienyl is toxic toAedes aegypti larvae in the dark, but its activity is much enhanced in the presence of ultraviolet light. The development of first-instar larvae treated with alpha-terthienyl and ultraviolet light was followed until the emergence of adults. The LC50 value for first instars was about 0.002 ppm. Practically all the larvae which survived 24 hr reached adulthood. Fourth-instar larvae were also sensitive to photochemical treatment. When their development into adults was followed, the LC50 value was 0.45 ppm. Contrary to earlier reports, alpha-terthienyl was also phototoxic in pupae, but not when the adults were about to emerge. The LC50 value was ca. 0.06 ppm for pupae which were 1 or 2 days old. This is the first example where the activity of a photoinsecticide has been demonstrated in pupae. Alpha-terthienyl did not affect the hatching of eggs.  相似文献   
9.
LANDSAT (ERTS-1) multispectral scanner band 5 (0.6–0.7 μm) and band 7 (0.8–1.1 μm) images have been visually interpreted to prepare geologic, tectonic and geomorphologic maps of the Mentese region of southwestern Turkey. Band 7 was most valuable for identifying geologic formations, tectonic fault lines and geomorphologic slope contrast. Band 5 supplemented the information obtained from band 7, by providing information on rock-soil boundaries, tectonic relationships between vegetation and structure, and vegetational tonal differences between steep slopes and flat surfaces.  相似文献   
10.
Cocaine is one of the most widely abused illicit drugs worldwide and has long been recognised as an agent of cardiac dysfunction in numerous cases of drug overdose. Cocaine has previously been shown to up-regulate cytoskeletal rearrangements and morphological changes in numerous tissues; however, previous literature observes such changes primarily in clinical case reports and addiction studies. An investigation into the fundamental cytoskeletal parameters of migration, adhesion and proliferation were studied to determine the cytoskeletal and cytotoxic basis of cocaine in cardiac cells. Treatment of cardiac myocytes with cocaine increased cell migration and adhesion (p < 0.05), with no effect on cell proliferation, except with higher doses eliciting (1–10 μg/mL) its diminution and increase in cell death. Cocaine downregulated phosphorylation of cofilin, decreased expression of adhesion modulators (integrin-β3) and increased expression of ezirin within three hours of 1 μg/mL treatments. These functional responses were associated with changes in cellular morphology, including alterations in membrane stability and a stellate-like phenotype with less compaction between cells. Higher dose treatments of cocaine (5–10 μg/mL) were associated with significant cardiomyocyte cell death (p < 0.05) and loss of cellular architecture. These results highlight the importance of cocaine in mediating cardiomyocyte function and cytotoxicity associated with the possible loss of intercellular contacts required to maintain normal cell viability, with implications for cardiotoxicity relating to hypertrophy and fibrogenesis.  相似文献   
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