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This work presents a rapid and facile way to access the cell wall of wood with magnetic nanoparticles (NPs), providing insights into a method of wood modification to prepare hybrid bio-based functional materials. Diffusion-driven infiltration into Scots pine (Pinus sylvestris L.) sapwood was achieved using colloidal Fe3O4 nanoparticles. Optical microscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray powder diffraction analyses were used to detect and assess the accessibility of the cell wall to Fe3O4. The structural changes, filling of tracheids (cell lumina), and NP infiltration depth were further evaluated by performing X-ray microcomputed tomography analysis. Fourier transform infrared spectroscopy was used to assess the chemical changes in Scots pine induced by the interaction of the wood with the solvent. The thermal stability of Fe3O4-modified wood was studied by thermogravimetric analysis. Successful infiltration of the Fe3O4 NPs was confirmed by measuring the magnetic properties of cross-sectioned layers of the modified wood. The results indicate the feasibility of creating multiple functionalities that may lead to many future applications, including structural nanomaterials with desirable thermal properties, magnetic devices, and sensors.

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In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure. This resulted, likely due to substrate surface influence, in all coatings having mixed phases of both garnet and perovskite. Thermogravimetric (TG) analysis of the precursor gels was carried out. All the samples were investigated by X-ray powder diffraction (XRD) analysis. The coatings were also investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Mössbauer spectroscopy. Magnetic measurements were also carried out.

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Over the past decade, in the light of intensive robotisation, job insecurity referring to the employees' overall concern about the continued availability of their jobs in the future has become a hot topic. A general assumption supported by the findings is that job insecurity causes far-reaching negative consequences for the employee well-being and health, attitudes towards the job and organisation, and behaviours at work. However, the focus on behavioural outcomes, especially on employee performance at work, is still scant. Trying to narrow the gap, the paper aims at revealing the linkage between job insecurity and two dimensions of performance, namely task performance and organisational citizenship behaviour. Building on the hindrance stressor dimension of the stress model, the paper claims that a negative relationship exists between the constructs. Quantitative data were collected in a survey of robotised production lines operators working in the furniture sector in Lithuania. As predicted, the results revealed that job insecurity had a negative impact on both the task performance and organisational citizenship behaviour. These findings affirmed that job insecurity was a hindrance stressor, which needed to be considered when managing human resources in a robotised production environment.

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Over the past decade, job insecurity referring to the employees' perceived threat to the continuity and stability of employment as it is currently experienced has become a hot topic. A general assumption, supported by the findings, is that job insecurity causes far-reaching negative consequences for the employee health and well-being, attitudes toward organization and the job, and behaviors at work. However, the focus on behavioral outcomes, especially on employee performance at work, is still scant. Moreover, the literature remains fragmented concerning the impact of job insecurity on employee trust in the organization and how the trust influences employee subjective well-being (SWB), which in turn affects employee performance. Consequently, the link between job insecurity and SWB needs more investigation. Trying to narrow the gap, the paper aims at revealing the linkage between job insecurity, trust in the organization, SWB, and task performance. Quantitative data were collected in Lithuania. As predicted, the results revealed that job insecurity had a negative impact on trust in the organization and employee SWB. In case of linkage between job insecurity and task performance, the hypothesis was rejected. In general, these findings affirmed that job insecurity was a hindrance stressor, which needed to be considered when managing human resources in the current volatility, uncertainty, complexity, and ambiguity context.

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Sustainability needs the socially responsible orientation of public institutions, but not only externally. How civil servants and municipal employees consider what local governments do in relation to their internal social responsibility is the main question of this study. Through structural equation modelling and a sample of 294 employees in local governments in a Spanish region (Extremadura), it is demonstrated that responsible job position design, as well as good communication and team building, both have positive and significant effects on the personal identification of employees with the city council. That has been interpreted as the essence of internal social responsibility and the first step for building external social responsibility at the municipal level. Practical implications and future directions are discussed.

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The accelerated movement of people towards cities led to the fact that the world's urban population is now growing by 60-million persons per year. The increased number of cities' population has a significant impact on the produced volume of household waste, which must be collected and recycled in time. The collection of household waste, especially in downtown areas, has a wide range of challenges; the collection system must be reliable, flexible, cost efficient, and green. Within the frame of this paper, the authors describe the application possibilities of Industry 4.0 technologies in waste collection solutions and the optimization potential in their processes. After a systematic literature review, this paper introduces the waste collection process of downtowns as a cyber-physical system. A mathematical model of this waste collection process is described, which incorporates routing, assignment, and scheduling problems. The objectives of the model are the followings: (1) optimal assignment of waste sources to garbage trucks; (2) scheduling of the waste collection through routing of each garbage truck to minimize the total operation cost, increase reliability while comprehensive environmental indicators that have great impact on public health are to be taken into consideration. Next, a binary bat algorithm is described, whose performance is validated with different benchmark functions. The scenario analysis validates the model and then evaluates its performance to increase the cost-efficiency and warrant environmental awareness of waste collection process.

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The objective of this study was to explore an effect of the combined inorganic materials on the wood hardness and flame-retardancy properties in a concept of sustainable material management. Herein, the reinforcement of Scots pine (Pinus sylvestris L.) sapwood with sodium silicate and TiO2 nanoparticles via vacuum-pressure technique is reported. Pyrolysis of modified wood was studied by TG-FTIR analysis; the results showed that maximum weight loss for the modified wood was obtained at 40-50 °C lower temperatures compared to the reference untreated wood. The Gram-Schmidt profiles and spectra extracted at maxima absorption from Gram-Schmidt plots indicated chemical changes in wood-inorganic composites. SEM/EDS analysis revealed the presence of Na-O-Si solid gel within the wood-cell lumen and showed that TiO2 was homogeneously distributed within the amorphous Na-O-Si glass-forming phase to form a thin surface coating. EDS mapping further revealed the higher diffusivity of sodium into the cell wall compared to the silicon compound. The presence of amorphous sodium silicate and nano-TiO2 was additionally confirmed by XRD analysis. FTIR spectra confirmed the chemical changes in Scots pine sapwood induced by alkalization. Brinell hardness test showed that the hardness of the modified wood increased with the highest value (44% increase in hardness) obtained for 10% Na2SiO3-nTiO2 modified wood. The results showed good correlation between TG and flammability test; limiting oxygen index (LOI) values for the wood-inorganic composites increased by 9-14% compared to the untreated wood.

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[This corrects the article DOI: 10.1039/C9RA05200C.].