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31.
Several empirical studies have proved that better organisational learning induces higher organisational performance. However, none of them addressed the issue of organisational learning process simultaneously in several countries. In our contribution, we aim to test differences in the way companies learn in Slovenia, Croatia, and Malaysia. We used the OLIMP questionnaire, a measurement instrument developed and tested by [Dimovski, V. (1994), Organisational learning and competitive advantage. PhD Thesis, Cleveland, Ohio; Dimovski, V., & Škerlavaj, M. (2005). Performance effects of organisational learning in a transitional economy. Problems and Perspectives in Management 3(4), 56–67]. It employs three measurement variables (information acquisition, information interpretation, and behavioural and cognitive changes) as well as 38 items (presented in the paper) to measure the organisational learning construct. In autumn 2005 data from 203 Slovenian, 202 Croatian and 300 Malaysian companies were gathered. The results indicate that companies in all three countries under scrutiny are closest in terms of behavioural and cognitive changes, meaning that globalisation and other challenges of the modern business environment demand all of them to change and adapt quickly. However, the ways they are coping with these challenges are different. There are more similarities than dissimilarities between Slovenia and Croatia, while this is not the case when comparing both countries to Malaysia. When acquiring information, Slovenian and Croatian companies rely more on internal sources (own employees, past decisions, etc.), while Malaysian companies tend to rely more on external sources and more often have employees dedicated to searching for external information. When trying to interpret the information acquired, Slovenian and Croatian companies rely more on personal contacts, informal team meetings and believe that information given to subordinates must be simple and concise, while Malaysian companies tend to use more formal collective decision-making and written communication to understand the meaning of information.  相似文献   
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33.
The solid solubility of the aliovalent dopants Fe3+ and Nb5+ in the BaBi4Ti4O15 compound, a member of the family of Aurivillius bismuth-based layer-structure perovskites, has been studied using quantitative wavelength-dispersive spectroscopic microanalysis (SEM/EPMA) in combination with X-ray powder diffractometry (XRPD). The samples with nominal (starting) compositions corresponding to the chemical formulas BaBi4Ti4–4 X Fe4 X O15 and BaBi4Ti4–4 X Nb4 X O15 were prepared by hot forging a mixture of BaTiO3 and Bi4Ti3O12 with additions of Fe2O3 or Nb2O5 followed by a long annealing at 1100°C. The study showed that an excess charge introduced into the structure by the substitution of Ti4+ ions with aliovalent dopants was preferentially compensated by a change in the ratio of Ba2+ to Bi3+ ions in the host structure according to the general formulas of the solid solutions Ba1–4 X Bi4+4 X Ti4–4 X Fe'4 X O15 and Ba1+4 X Bi4–4 X Ti4–4 X Nb·4 X O15.  相似文献   
34.
Guanine-rich DNA sequences self-assemble into highly stable fourfold structures known as DNA-quadruplexes (or G-quadruplexes). G-quadruplexes have furthermore the tendency to associate into one-dimensional supramolecular aggregates termed G-wires. We studied the formation of G-wires in solutions of the sequences d(G4C2)n with n = 1, 2, and 4. The d(G4C2)n repeats, which are associated with some fatal neurological disorders, especially amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), represent a challenging research topic due to their extensive structural polymorphism. We used dynamic light scattering (DLS) to measure translational diffusion coefficients and consequently resolve the length of the larger aggregates formed in solution. We found that all three sequences assemble into longer structures than previously reported. The d(G4C2) formed extremely long G-wires with lengths beyond 80 nm. The d(G4C2)2 formed a relatively short stacked dimeric quadruplex, while d(G4C2)4 formed multimers corresponding to seven stacked intramolecular quadruplexes. Profound differences between the multimerization properties of the investigated sequences were also confirmed by the AFM imaging of surface films. We propose that π-π stacking of the basic G-quadruplex units plays a vital role in the multimerization mechanism, which might be relevant for transformation from the regular medium-length to disease-related long d(G4C2)n repeats.  相似文献   
35.
A new, simple, low-temperature method for the synthesis of superparamagnetic, photocatalytic, nanocomposite particles for applications in the decomposition of pollutants in water is presented. The method is based on the coating of clusters of superparamagnetic maghemite (γ-Fe2O3) nanoparticles with a photocatalytic anatase layer using the hydrolysis of aqueous TiOSO4. The clusters of an appropriate size between 100 and 200 nm form by the simultaneous agglomeration of the aminopropyl-triethoxy-silane-grafted maghemite nanoparticles with a size of approximately 15 nm in a suspension of diluted TiOSO4. During a sudden increase of pH with the addition of NaOH the titania is heterogeneously nucleated at the cluster surfaces. If the hydrolysis was conducted at an elevated temperature of 90 °C, the titania layer was nanocrystalline anatase. The composition of the nanocomposite particles, i.e., the thickness of the anatase layer, can be controlled simply by changing the starting TiOSO4/Fe2O3 ratio for low titania contents, and by multiple coatings to get high titania contents. The photocatalytic activity of the nanocomposites was evaluated in the photocatalytic decomposition of formic acid. The activity seems to increase with an increase in the thickness and the crystallinity of the anatase coating, whereas it decreased after the calcination of the as-synthesized nanocomposite. The coating of the maghemite nanoparticles with a thin layer of insulating silica also slightly improves the photocatalytic activity.  相似文献   
36.
Composite coatings from different volume ratios of hexaferrite (BaFe12O19 or SrFe12O19) and polyethylene were prepared, for the first time, with flame spraying. The hexaferrite phase retained its crystal structure and microstructure during the process, while the polyethylene melted and resolidified. The coatings showed magnetic hysteresis loops with high coercivities. The measured electromagnetic behaviour proved that the studied composite coatings would be suitable for electromagnetic wave absorbers in the U-band.  相似文献   
37.
Superparamagnetic Ba-hexaferrite nanoparticles were prepared using modified hydrothermal synthesis. The precursor and hydroxide [OH] concentrations were optimized and the synthesis temperature and time were drastically reduced. The size and the morphology of synthesized nanoparticles was confirmed by transmission electron microscopy (TEM) images. The crystal structure of the nanoparticles was characterized by X-ray diffraction data. Powders synthesized at 160 °C exhibit a bimodal particle size distribution while those synthesized at TS = 150 °C show a monomodal particle size distribution. Zero-field-cooling (ZFC) and field-cooling (FC) magnetization measurements were performed using a superconducting quantum interference device magnetometer from 2 to 300 K to investigate the magnetic properties of nanoparticles. The FC/ZFC magnetization measurements showed a typical superparamagnetic behavior. The synthesized superparamagnetic particles exhibit a disc-like shape, in average 11 nm wide and 3 nm thick with a room temperature magnetization of approximately 10 Am2/kg at 5 T.  相似文献   
38.
Copper ethanolamine preservatives are one of the most important solutions for wood preservation. As copper itself can not ensure sufficient protection against wood destroying organisms we combine it with other co-biocides like quaternary ammonium compounds, azoles and/or boron. Influence of different boron compounds and octanoic acid on copper fixation as well as performance of spruce wood impregnated with different copper/ethanolamine/boron based aqueous solutions is described in this paper. Copper fixation was determined according to the modified ENV 1250 (1994) standard method, while performance against Antrodia vaillantii, Gloeophyllum trabeum and Trametes versicolor was tested according to the mini block procedure. The results showed that addition of boron increases copper leaching, but on the contrary improves performance against wood decay fungi. On the other hand, addition of octanoic acid improves copper fixation, and slightly decreases resistance against copper tolerant fungi.  相似文献   
39.
Within the Slovenian region of Istria, the olive growing and oil production industry is strong. This industry has a long history and the olives grown here have high levels of biologically active compounds including a variety of phenolic compounds. Using residual materials generated by this industry in potential wood protection systems would not only valorise low-value materials and stimulate rural economies but would also provide an alternative to currently used oil-based protection systems. The objective of this study was to produce an oil treatment for wood protection and assess its efficacy in reducing leaching, weathering effects, and fungal decay. Two maleinisation techniques were used to chemically modify low-value lampante oil in an attempt to limit leaching when impregnated in wood. Pinus sylvestris (Scots pine) and Fagus sylvatica (European beech) were treated with the modified oils and underwent leaching, accelerated weathering, and decay tests. Leaching of the treatment oils was relatively low compared with other experiments and beech wood specimens treated with a direct maleinisation treatment showed improvement in performance compared to control specimens. In addition, it was found that the modified oils were not completely removed from the wood after solvent extraction indicating that they could potentially be used as an immobilisation agent in combination with other treatments thereby reducing the amount of active component of the protective agent.  相似文献   
40.
Novel polymeric systems with antibacterial properties based on medical-grade polyvinyl chloride and antibiotics (Ampicillin, Minocycline, and Rifampicin) in the concentrations up to 1 wt% were prepared by thermoplastic compounding. Thermal stability of the antibiotics was corroborated by IR spectroscopy, X-ray diffraction, differential scanning calorimetry, and 1H nuclear magnetic resonance spectroscopy. The effect of chemical structure on mechanical properties of the prepared systems was determined by tensile testing measurements and correlated with optical microscopy observations. In vitro antibacterial properties of samples were determined by agar diffusion and adhesion test against Gram-negative and Gram-positive bacteria. Antibiotic release experiments in distilled water and physiological saline solution and follow-up detecting by Ultraviolet–Visible spectroscopy were carried out. A mathematical model was applied to evaluate the release kinetics of the antibiotics from prepared polymeric systems. The results show significant influence of antibiotic’s chemical structure on all studied characteristics of the systems due to the various interactions with polyvinyl chloride matrix.  相似文献   
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