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The purpose of this paper is to propose a simple physical evaporation route in which catalyst‐free zinc oxide (ZnO) nanoscrewdrivers were deposited on silicon (Si) (111) substrates.

Prior to the deposition, the Si (111) wafer was cut into pieces of 2×2 cm². Then, the wafers were dipped for 1 min into mixture buffered oxide etchant to remove native oxide. Then, the samples were rinsed in an ultrasonic bath cleaned with boiling acetone, ethanol, and de‐ionized (DI) water for 10 min. Lastly, the wafers were rinsed in 25 ml DI water in stirred and then were blown dry with nitrogen. In this technique, the starting material is high‐purity metallic zinc (Zn) powder (99.99 per cent pure). Following, the Zn films were then annealed under air environment in the furnace at 500°C for 1 h deprived of any catalysts.

These ZnO samples were studied by scanning electron microscopy, high‐resolution X‐ray diffraction (HR‐XRD), and photoluminescence (PL) spectroscopy. Atomic force microscope (AFM) images were applied to ascertain surface morphology of produced ZnO nanoscrewdrivers. XRD pattern confirmed that the ZnO nanoscrewdrivers were of polycrystalline structure in universe with a hexagonal close packed type and c‐axis is perpendicular to the substrate. The peak at 34° correspond to the reflection planes of ZnO(002) crystallographic plane is perceived. The AFM surface images disclosed that the surfaces of produced ZnO thin films are not smooth. The PL spectrum of as‐synthesized nanoscrewdrivers shows a UV emission peak at 380 nm and a broad green emission peak at 500 nm.

The paper reports on a simple physical evaporation route, ZnO nanoscrewdrivers were synthesized via the thermal evaporation of the high‐purity Zn powders and annealed at 500°C under air atmosphere without introducing any hetero‐metal catalysts or other carrier gases approach.

The purpose of this paper is to lay the necessary conceptual and empirical groundwork that advances knowledge about paternalistic leadership (PL). PL is reinterpreted as a leadership style consisting of authoritative, moral and benevolent leadership. The mediating role of trust is examined, and a formal, unified construct model of PL is suggested through evidence of construct validity.

An on-site survey was used to collect data from 312 full-time employees in nine organizations in China. Factor analysis, reliability and validity test, and an analysis of bivariate correlations were conducted.

The new construct of PL achieved a positive alignment and coherence among the three dimensions. Subordinates’ trust was found to be critical for paternalistic leaders to be perceived as effective leaders.

Leadership and its effectiveness were examined only at the dyadic level. The levels of the supervisors and their effectiveness differ because some were from middle management, whereas others were from first line managers.

Trust is an important explanatory mechanism for the relationship between PL and employee performance, especially in China. It is a key factor that creates loyalty and builds a good relationship between leaders and subordinates.

Trust signals a strong sense of sharing within the relationship. It induces positive emotional feelings in their leader by the subordinates and, therefore, taps into positive evaluations about the effectiveness of their leader.

This study developed the theoretical underpinnings and provided measurement instruments for PL. It offered a formal, unified construct model of PL.

The purpose of this study is to examine the direct effect of paternalistic leadership on the employee’s feedback orientation in the Egyptian public sector. It also investigates the mediating effect of the employee’s workplace well-being on the relationship between paternalistic leadership and feedback orientation.

The study uses a questionnaire that consists of measures adopted from existing and tested scales. A mediation analysis is conducted using structure equation modelling to examine the hypothesized relationships.

The findings reveal that paternalistic leadership is positively associated with feedback utility, accountability, awareness and self-efficacy. Moreover, the employee’s workplace well-being significantly mediates the proposed relationship between paternalistic leadership and the aforementioned dimensions of feedback orientation.

The relationship between paternalistic leadership and feedback orientation has received an extremely limited academic attention. This study hypothesizes a mediation model which investigates the leadership, well-being and feedback associations in the traditionally under-researched Egyptian context.

The purpose of this paper is to study the structural and optical characterization of Al_x In_y Ga_1−x−y N quaternary epilayers, which were grown on c‐plane (0001) sapphire substrates with AlN as buffer layers using plasma assisted molecular beam epitaxy technique with indium (In) mole fraction y ranging from 0.0 to 0.1 and constant aluminum (Al) mole fraction x=0.06.

High‐resolution X‐ray diffraction rocking curve (HRXRD‐RC), scanning electron microscopy (SEM), energy dispersive X‐ray spectrometry (EDX), and photoluminescence (PL) spectroscopy have been measured on quaternary Al_x In_y Ga_1−x−y N thin films at room temperature.

HRXRD‐RC measurements confirmed that the Al_x In_y Ga_1−x−y N alloys had wurtzite structure. SEM images, element composition analysis by EDX, provided the evidence to show the existence of defects inside the samples contaminated by silicon from previous growth leading to nonuniformity of the epilayers, which caused decreased in the quality of the samples. PL spectra show reducing of the integrated intensity and an increasing red shift with increasing in content with reference to the ternary sample Al_0.06Ga_0.94N. The existence of a large amount of nonradiative recombination centers are responsible for the reduced the luminescence and the red shift provided evidence to an increase in composition inside the Al_x In_y Ga_1−x−y N quaternary alloys. Photoluminescence is used to determine the behavior of the near band edge emission represent the energy band gap of the quaternary films. The energy band gap decreases with increasing In composition from 0.01 to 0.1 mole fraction. This trend is expected since the incorporation of in reduced the energy band gap of ternary Al_0.06Ga_0.94N (3.529 eV). We have also investigated the bowing parameter of the variation of energy band gaps and found it to be very sensitive on in composition. A value of b=10.95 have been obtain for our quaternary Al_x In_y Ga_1−x−y N alloys.

This study on quaternary samples described in this paper, clearly indicates that the present of defects due to impurity contaminations has a dominant role in determining the structural and optical properties of Al_x In_y Ga_1−x−y N quaternary alloys.

The crystalline quality of wider direct band gap semiconductor (3.4 eV) h-GaN epilayer grown on Si (111) is evaluated by different growth approaches and by using different interlayer's. The investigations of GaN epilayer crystal quality for the template of converted porous GaN layer formed by novel nitridation process of thin (2 and 0.5 μm) GaAs layer on Si (111) and on C⁺ ion implanted very thin SiC layer formed on Si (111) and grown ambient effect are made. Epilayer grown on thinner non-isoelectronic converted SiC templates is found to broaden its PL line width whereas epilayer grown on porously converted GaN layer fromed from iso- electronic GaAs (111) layer on Si (111) is found narrow line width. H₂ ambient grown film better crystalline quality and higher PL Ex. peak energy is found as compared to N₂ ambient grown film. Low temperature PL measurement, similarity between defect related donor-acceptor peaks (DAP) to defect related yellow band luminescence at the room temperature PL measurement is also found. Grown epilayer different characterization reveals better crystalline quality h-GaN is achieved by using thin iso-electronic GaAS interlayer on Si (111) with H₂ grown ambient.

To contribute to the understanding of how to manage turnover, the purpose of this paper is to determine if sales managers have the ability to predict high levels of propensity to leave (PL) from variables readily available in personnel records, and on commonly used employee surveys.

The data used for the analysis of the study variables were collected from the sales forces of a total of ten firms across a variety of consumer and industrial product categories, resulting in a sample of 604 respondents. Data were analyzed via multiple discriminant analysis.

The analysis and test results demonstrate that discriminant sets of attitudinal variables, personal characteristics, and aspects of the job can be identified and used to establish meaningful classifications of a salesperson's PL. Organizational commitment, satisfaction with pay, family status, job involvement, level of education, and compensation plan were all found to be significant. Analysis fails to support the existence of several attitudinal variables generally thought to be predictors of PL.

The overarching implication to be drawn is that any effort to address salesperson turnover must be holistic, rather than limited to a narrow set of variables. These findings hold implications for sales management researchers and human resource/personnel managers.

The purpose of this paper is to enhance the efficiency of the LED by introducing three-step magnesium (Mg) doping profile. Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region). Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region).

Indium gallium nitride (InGaN)–based light-emitting diode (LED) was grown on a 4-inch c-plane patterned sapphire substrate using metal organic chemical vapor deposition. The Cp₂Mg flow rates for the second and third p-GaN layers were set at 50 sccm and 325 sccm, respectively. For the first p-GaN layer, the Cp₂Mg flow rate varied from 150 sccm to 300 sccm to achieve different Mg dopant concentrations.

The full width at half maximum (FWHM) for the GaN (102) plane increases with increasing Cp₂Mg flow rate. FWHM for the sample with 150, 250 and 300 sccm Cp₂Mg flow rates was 233 arcsec, 236 arcsec and 245 arcsec, respectively. This result indicates that the edge and mixed dislocations in the p-GaN layer were increased with increasing Cp₂Mg flow rate. Atomic force microscopy (AFM) results reveal that the sample grown with 300 sccm exhibits the highest surface roughness, followed by 150 sccm and 250 sccm. The surface roughness of these samples is 2.40 nm, 2.12 nm and 2.08 nm, respectively. Simultaneously, the photoluminescence (PL) spectrum of the 250 sccm sample shows the highest band edge intensity over the yellow band ratio compared to that of other samples. The light output power measurements found that the sample with 250 sccm exhibits high output power because of sufficient hole injection toward the active region.

Through this study, the three steps of the Mg profile on the p-GaN layer were proposed to show high-efficiency InGaN-based LED. The optimal Mg concentration was studied on the first p-GaN layer (i.e. layer close to active region) to improve the LED performance by varying the Cp₂Mg flow rate. This finding was in line with the result of PL and AFM results when the samples with 250 sccm have the highest Mg acceptor and good surface quality of the p-GaN layer. It can be deduced that the first p-GaN layer doping has a significant effect on the crystalline quality, surface roughness and light emission properties of the LED epi structure.

The purpose of this paper is to synthesize Si (porous silicon (PS)) by laser‐induced etching (LIE) technique. The LIE process has the added advantage of a controlling size and optical properties without using of electrodes. The LIE process is a promising technique for fabricating many optoelectronic devices including: light‐emitting devices, detectors, sensors and large‐scale integrated circuits.

PS has been fabricated by LIE technique. Surface morphology and structural properties of nanostructures are characterized by using scanning electron microscopy and X‐ray diffraction (XRD). Photoluminescence (PL) measurement is also performed at room temperature by using He‐Cd laser (λ=325 nm) and Raman scattering has been investigated using Ar⁺ laser (λ=514 nm).

Surface morphology indicated that chemical reaction has been initiated with laser power density of 12 W/cm², resulting in irregular structure. Micro‐columns are structured on surface with laser power density of 25 W/cm². The pores structures are confined to smaller size, and the walls between the pore become extremely thin and shorter at 64 W/cm² power density and 120 min irradiation time. PL spectra at room temperature for PS prepared at power density of 64 W/cm² and irradiation time of 120 min shows the blue shift of PL at 400 nm and the full‐width and half maximum is about 60 nm. The broadening of the band gap energy occurs with a decrease of the crystallite size. The average diameter of nanosize Si crystallites is about 6‐10 nm. XRD indicated that the broadening in spectrum is due to the small size crystallites.

LIE processes have been used to produce high‐luminescent nanocrystallites with small size and size distribution, which is due to the quantum confinement effect.

There is increasing managerial and academic interest in understanding behavioural loyalty to private label (PL) brands. A widely used behavioural loyalty measure is share of category requirements, or “SCR”. This study aims to examine why some PLs enjoy higher levels of SCR compared to others.

The study models consumer purchase data using the well-accepted NBD-Dirichlet model to identify the circumstances in which PL brands exhibit higher (“excess”) or lower SCR than expected.

The study finds four factors linked to excess SCR for PLs. They are: higher share of overall category sales accounted for by the PL within the retailer's stores, higher penetration of the category by the retailer, low relative price of the PL, and lastly, lower average purchase frequency for the category overall.

While the study uses 13 product categories, its geographic scope is limited to the UK. Further research could examine how the findings generalize to other markets.

The study is original in that it identifies factors that are linked to behavioural loyalty toward specific PL brands. The findings will help marketers in brand management and retailing to understand and contextualize brand performance metrics for PL brands.

The purpose of this paper is to investigate three preparation processes and the photoluminescent (PL) properties of PbS/poly(p‐phenylene vinylene) (PPV) composite fibres.

By the combination of electrospinning technology, chemical vapour deposition and chemical liquid deposition, PbS/PPV composite nanofibres were prepared by three simple methods. The morphologies of the fibres and the PL properties were researched with the transmission electron microscopy (TEM) and the eclipse fluorescence spectrophotometer.

By different synthetic methods, the dispersion morphologies of PbS nanoparticles and the PL properties of their respective PbS/PPV composite fibres were different. Moreover, the effects of PbS nanoparticles on the luminescence quenching of the PPV were observed in all the synthesised PbS/PPV composite fibres, respectively.

The dispersion morphologies of PbS nanoparticles were not uniform enough.

A new method was used for preparing nanoparticles/polymer composite fibres.

The combination of electrospinning technology and chemical liquid deposition was used for the first time to fabricate the sulfide/polymer composite fibres. In addition, we hope that the results obtained here will provide some useful evidences for the interaction mechanism between IV‐VI group semiconductors and conjugated polymers, and the prepared composite fibres will have applications in the nano‐optoelectronic field.