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The purpose of the article is to provide further evidence for the work environment hypothesis. According to the work environment hypothesis and as documented by empirical evidence, organizational factors play a crucial role in the development of workplace bullying. However, to better understand and prevent bullying at work and establish sustainable, responsible and ethical workplaces, it is crucial to understand which organizational factors are particularly important in the development of bullying and how these factors, independently and combined, act as precursors to bullying over time. One prominent theory that explains how organizational and individual factors interact is the affective events theory (AET).

In a two-wave, time-lagged study (N = 364), the authors apply AET to test and explain the interplay of organizational factors in the development of bullying at work.

The results revealed that supportive and fair leadership moderates the relationship between role stress and exposure to workplace bullying.

Knowledge of the buffering role of supportive and fair leadership practices is important when implementing organizational interventions aimed at preventing bullying at work.

Although previous studies have shown the general protecting effects of supportive leadership on exposure to bullying, the current study indicates that high level of supportive and fair leadership practices decreases the level of exposure to bullying, even when role ambiguity and role conflict are relatively high.

The purpose of this study was the comparison and analysis of the electrical parameters of two kinds of silicon solar cells (mono- and multicrystalline) of different emitter resistance.

By controlling of diffusion parameters, silicon mono- (Cz-Si) and multicrystalline (mc-Si) solar cells with different emitter resistance values were produced – 22 and 48 Ω/□. On the basis of current-voltage measurements of cells and contact resistance mapping, the properties of final solar cells based on two different materials were compared. Additionally, the influence of temperature on PV cells efficiency and open circuit voltage (U_oc) were investigated. The PC1D simulation was useful to determine spectral dependence of external quantum efficiency of solar cells with different emitter resistance. The silicon solar cells of 25 cm² area and 240 µm thickness were investigated.

Considering the all stages of cell technology, the best structure is silicon solar cell with sheet resistance (R_sheet) of 45-48 Ω/□. Producing of an emitter with this resistance allowed to obtain cells with a fill factor between 0.725 and 0.758, U_oc between 585 and 612 mV, short circuit current (I_sc) between 724 and 820 mA.

Measurements and analysis confirmed that mono- and multicrystalline silicon solar cells with 48 Ω/□ emitter resistance have better parameters than cells with R_sheet of 22 Ω/□. The contact resistance is the highest for mc-Si with R_sheet of 48 Ω/□ and reaches the value 3.8 Ωcm.

The paper aims to present results of investigations carried out on the front electrode of the solar cell. The front-side electrode for solar cells based on crystalline material is obtained by the screen printing method. Screen printing has been the prevailing method of electrode deposition because of its low cost. One of the ways to improve the cell efficiency and reduce the production costs is a further refinement of the metal electrode screen printing process.

The researches were focused on the modification of mechanical parameters of screen printing process to ensure the best possible cross-section of the front electrode geometry. The main printing process parameters were constant, however, the print speed was variable. The obtained fine line of front contact was characterized morphologically – the dimension and geometry of the front contact cross-section – by scanning electron microscopy technique.

The thin paths of 100 μm in width were screen printed applying a new silver-paste made by Du Pont. The printing speed has significant effect on print quality in the way that the lower speed enhanced the printed results.

For newest pastes (e.g. PV17D) influence of screen printing parameters on the front metallic electrodes geometry of solar cell is not so significant. Presented screen printing process can still give good results, but the further optimization for the new paste must be performed to achieve better cross-section geometry.

This paper confirms that one-step screen printing process can still give good results. The screen printed thin paths of 100 μm in width have good cross-section aspect ratio.

The paper aims to show application of the electrochemically deposited coatings for thickening of the screen printed electric paths potentially applied in photovoltaic cells.

The electric paths were screen printed with the use of silver-based paste. The paths were thickened by electrodeposition of thin copper layer in potentiostatic regime from surfactant-free plating bath. The morphology and surface quality of the paths were studied by imaging with scanning electron microscopy.

The electric paths can be thickened successfully, but quality for the screen printed substrate determines quality of deposited layer. The EDX analysis confirmed that the deposited copper layer covered uniformly the printed paths.

The adhesion of the copper-covered path to the silicon wafer surface depends on adhesion of the original screen printed path.

This paper confirms that electrodeposited copper can be applied for screen printed silver paths thickening in a controllable way.

The purpose of this study is to verify the possibility of applying alumina (Al₂O₃) as the passivation and antireflective coating in silicon solar cells.

Model of a studied structure contains the following layers: Al₂O₃/n+/n-type Si/p+/Al₂O₃. Optical parameters of the aluminium oxide films on silicon wafers were measured in the range of wavelengths from 250 to 1,400 nm with a spectrophotometer Perkin Elmer Lambda 900. The minority carrier lifetime at the start of the n-type Si base material and after each of the next technological process was analysed by a quasi-steady-state photoconductance technique. The electrical parameters of the solar cells fabricated with four different thickness of the Al₂O₃ layer were determined on the basis of the current-voltage (I-V) characteristics. The silicon solar cells of 25 cm² area and 300 µm thickness were investigated.

The optimum thickness of alumina as passivation layer is 90 nm. However, considering also antireflective properties of the first layer of a photovoltaic cell, the best structure is silicon with alumina passivation layer of 30 nm thickness and with TiO2 antireflective coatings of 60 nm thickness. Such solution has allowed to produce the cells with the fill factor of 0.77 and open circuit voltage of 618 mV.

Measurements confirmed the possibility of applying the Al₂O₃ as a passivation and antireflective coating (obtained by atomic layer deposition method) for improving the efficiency of solar cells.