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Niobium Nitride (NbN) was interesting material for its applications in the medicinal tools or tools field (corresponding to saline serum media) as well as in mechanical properties. The aim of this work was depositing NbN thin films on two types of substrates (stainless steel (SS304) and silicon (100)) using plasma technique at varied powers (100–150 W).

DC magnetron sputtering technique at different powers were used to synthesis NbN films. Film structure was studied using X-ray diffraction (XRD) pattern. Rutherford elastic backscattering and energy dispersive X-ray were used to examine the deposited film composition. The films morphology was studied via atomic force microscopy and scanning electron microscopy images. Corrosion resistance of the three NbN/SS304 films was studied in 0.9% NaCl environment (physiological standard saline).

All properties could be controlled by the modification of DC power, where the crystallinity of samples was changed and consequently the corrosion and microhardness were modified, which correlated with the power. NbN film deposited at higher power (150 W) has shown better corrosion resistance (0.9% NaCl), which had smaller grain size (smoother) and was thicker.

The NbN films have a preferred orientation (111) matching to cubic structure phase. Corrosion resistance was enhanced for the NbN films compared to SS304 substrates (noncoating). Therefore, NbN films deposited on SS304 substrate could be applied as medicinal tools as well as in mechanical fields.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique at room temperature. TiN target has been used to deposit TiN thin film under pure argon (100 percent Ar) gas. Additionally, Ti6Al4V alloy target has been used to deposit TiAlVN under nitrogen and argon gas (50 percent Ar and 50 percent N₂). In this paper, two substrate types have been used: stainless steel 304 and Si(100). This analysis has confirmed that the nitride films, (TiN/Si) and TiAlVN in both cases, have been produced. Energy Depressive X-ray Spectroscopy (EDX) measurement confirmed that the TiN/Si was stoichiometry, where the N/Ti ratio was about 1 with low oxygen contamination. The results obtained have indicated that the TiAlVN has more resistance to corrosion than TiN film in 3.5 percent NaCl at 25°C (seawater). Both films, TiAlVN/SS304 and TiN/SS304, have shown improved corrosion resistance compared with virgin 304 substrate. Microhardness was carried out using Vickers method; the microhardness values for TiN/SS304 and TiAlVN/SS304 were approximately 7.5 GPa and 25.3 GPa, respectively. The paper aims to discuss these issues.

The films were prepared by a DC magnetron sputtering system starting from high pure (99.99 percent) Ti6Al4V target (Al 6wt%, V 4wt% and balance Ti) in plasma discharge argon/nitrogen (50 percent Ar and 50 percent N₂) for deposition of TiAlVN film. Pure TiN target (99.99 percent) was used for preparation of TiN film in pure argon plasma. The diameter of target was 50 mm and the power applied for preparation of the two films was 100 W. A cylindrical high-vacuum chamber (Figure 2) made of stainless steel 316, with height 363 mm diameter, was fabricated locally. Scanning electron microscope images have been used to discover the films morphology. The composition of the films has been determined by EDX technique for films deposited on Si substrate. The electrochemical corrosion test was carried out using conventional three-electrode cell of 300 ml capacity by using Voltalab PGZ 301 system (France) using Tafel extrapolation method and electrochemical impedance spectroscopy techniques.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique without heating of the substrates holder. The effects of the composition of nitride films on mechanical and corrosion properties were investigated. The composition of the films has been determined by EDX technique. The effect of using titanium alloy (Ti with Al and V) on the composition and crystalline quality has been investigated. The microhardness is strongly dependent on the addition of the Al and V elements, and it consequently improves mechanical proprieties. The microhardness values for TiN/SS304 were approximately 7.5 GPa and 25.3 GPa for TiAlVN/SS304. They indicate that prepared films prevent the aggressive action of corrosion media.

TiN and TiAlVN films have been prepared by DC magnetron sputtering method at room temperature. Titanium nitride film, especially TiAlVN, is an effective method to improve the corrosion resistance of SS304. TiAlVN film has exhibited enhanced corrosion resistance and higher microhardness. Independent time-of-flight elastic recoil detection analysis has been used to determine the composition of the film.

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at different powers. Film structure has been analyzed by X-ray diffraction (XRD); the patterns showed that the films possesses a cubic structure with (111) preferred orientation. Photoluminance (PL) intensity of the films has been related to the crystallinity, which is varied with the power.

Scanning electron microscope (SEM) images have been used to discover the films’ morphology. The stoichiometry has been confirmed by energy dispersive X-ray spectroscopy (EDX) analysis. MicroRaman spectroscopy has been used to validate the film structure. Gas-sensing studies were carried out by means of a static gas chamber to sense acetone, ethanol, methanol, H₂O and NH₃ vapor in air ambient.

ZnS has a stoichiometric and cubic structure. The band gaps and photoluminance intensity of the films are correlated with the crystallinity, which is varied with the power. The EDX analysis approved the stoichiometry of the prepared films. Acetone, ethanol, humidity (H₂O), methanol and NH₃ vapor gases were used to justify the sensing properties at 25°C of the thickest ZnS film.

High-quality ZnS films have been obtained at different powers without annealing. Gases sensing properties at 25°C are justified for deposited ZnS films using acetone, ethanol, humidity (H₂O), methanol and NH₃ vapor gases. It reveals good response for NH₃ and humidity vapors at room temperature; the sensing functioning at this temperature was attractive in recent research.

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the direct current (DC) magnetron sputtering technique.

DC sputtering at different powers – 80, 100 and 120 W – was used to deposit ZrO₂ thin films onto different substrates (Si/SS304) without annealing of the substrate. Atomic force microscope (AFM), energy-dispersive X-ray spectroscopy (EDS), Tafel extrapolation and contact angle techniques were applied to investigate the surface roughness, chemical compositions, corrosion behavior and hydrophobicity of these films.

Results showed that the thickness of the deposited film increased with power increase, while the corrosion current decreased with power increase. AFM images indicated that the surface roughness decreased with an increase in DC power. EDS analysis showed that the thin film has a stoichiometric ZrO₂ (Zr:O 1:2) composition with basic uniformity. Water contact angle measurements indicated that the hydrophobicity of the synthesized films decreased with an increase in surface roughness.

DC magnetron sputtering technique is infrequently used to deposition thin films. The obtained thin films showed good hydrophobic and anticorrosion properties. Finally, results are compared with other deposition techniques.

This study aims to investigate to what extent the predictability of the standard and poor’s 500 (S&P 500) price levels is enhanced by investors’ sentiments extracted from social media content, specifically platform X.

Two recurrent neural network (RNN) models are developed. The first RNN model is merely based on historical records and technical indicators. In addition to the variables included in the first RNN model, the second RNN model comprises the outputs of the sentiment analysis, performed using the TextBlob library. The study was conducted between December 28, 2011, and December 30, 2021, over 10 years, to obtain better results by feeding the RNN models with a significant quantity of data by extending the period and capturing an extensive timespan.

Comparing the performance of both models reveals that the second model, with sentiment analysis inputs, yields superior outcomes. The mean absolute error (MAE) of the second model registered 72.44, approximately 50% lower than the MAE of the technical model, its percentage value, the mean absolute percentage error, recorded 2.16%, and finally, the median absolute percentage error reached a value of 1.30%. This underscores the significant influence of digital platforms in influencing the behavior of certain assets like the S&P 500, emphasizing the relevance of sentiment analysis from social media in financial forecasting.

This study contributes to the growing body of literature by highlighting the enhanced predictive power of deep learning models that incorporate investor sentiment from social media, thereby advancing the application of behavioral finance in financial forecasting.

This study aims to examine stock price synchronicity during the COVID-19 crisis using 32,452 firms from 61 countries. This paper explores the impact of government effectiveness on synchronicity while distinguishing between developed and emerging markets.

The research analysis employs ordinary OLS pooled regression analysis.

This paper presents worldwide evidence that stock price synchronicity was significantly higher during February and March 2020. This paper shows that synchronicity increased with the intensity of the crisis. In addition, the government's role reduced the COVID-19 impact on synchronicity, which was stronger in developed markets than in emerging markets.

The novelty of the study lies in documenting the impact of the COVID-19 pandemic on stock price synchronicity. The findings add to a deeper understanding of market behavior amid significant disruptive shocks.

The purpose of this paper is to propose and test a conceptual model that explores the effect of job rotation on employees' performance through the mediating role of organizational behavior (namely, motivation, organizational commitment, job satisfaction, job involvement and job burnout).

Data are gathered from employees in the tourism and aviation departments at travel agents category A in Egypt. In total, 788 questionnaires are analyzed using regression-based partial least squares structural equation modeling (PLS-SEM) using Smart PLS 3.21.

The results indicate that organizational behavior (motivation, organizational commitment, job satisfaction, job involvement and job burnout) plays mediation roles in the relationship between job rotation and employees' performance.

The study contributes to the current literature by linking job rotation to employees' performance through organizational behavior (motivation, organizational commitment, job satisfaction, job involvement and job burnout). The findings of the study hold practical and theoretical implications for tourism and hospitality organizations.

This study aims to determine the factors affecting the adoption of digital entrepreneurship among the pioneers of private schools in the Nineveh Governorate, using the unified theory of acceptance and use of technology (UTAUT). The study seeks to address an academic problem represented by the low level of interest in the research literature on digital entrepreneurship. By contrast, the problem in the field is the failure of several entrepreneurial organizations, in general, and private schools, in particular.

The researchers chose the private school sector in the Nineveh Governorate, Republic of Iraq, as the field of study. The targeted individuals represented school founders serving as investors and entrepreneurs, totaling 154 participants. The deductive approach was used as the main research method, with the survey approach as a sub-method. A questionnaire was used for data collection, and the researchers used structural equation modeling software, SmartPLS.

The results revealed that constructs such as effort expectation, social influence, facilitating conditions, behavioral intention and experience are factors contributing to predicting the transition to digital entrepreneurship.

This study contributes to bridging the academic gap identified in previous research and addresses the spatial gap by focusing on private schools in the Nineveh Governorate. It aims to assess the level of interest in adopting digital leadership within this context.

One of the most important implications of the results of the current research is the potential expansion of the use of digital entrepreneurship by understanding the behaviors of entrepreneurs. This understanding can have positive outcomes in attracting broad segments of society to engage in this type of work due to its low costs, low risks and the absence of the need for practicing licenses. Such an expansion could contribute to the establishment of digital pioneering projects aimed at reducing unemployment in society. Additionally, this study offers insights that can guide policymakers in the country toward establishing digital business incubators that provide a suitable work environment for initiating and supporting such projects.

The current study presents a unique contribution, represented by using the UTAUT, to identify the acceptance of digital entrepreneurship in private schools in Iraq. This can bring benefits to entrepreneurs and educational policymakers in the country.

This study aims to identify the main factors that drive the differences in the levels of forward-looking information disclosure (FLID) across four countries. This study goes beyond the firm-specific characteristics to the countries-specific factors to explain the observable differences in the level of FLID among the UK, Italian, Hong Kong and Chinese American Depositary Receipts (ADRs) firms trading in US Exchanges.

To validate the levels of FLID, corporate financial information environment (CFIE)-final reports structure extractor (FRSE) was conducted on the annual reports of a sample of 353 listed firm observations in 2020 across four different countries. Also, the ordinary least square regression model was used to examine the proposed relationships.

The empirical results indicate that the level of FLID is highest among the Chinese ADRs firms trading in US Exchanges and UK listed firms. Also, ownership concentration and gender diversity have a positive correlation with the level of FLID. Additionally, long-term orientation positively influences the level of FLID. Considering the moderation effect of power distance and masculinity dimensions, countries with larger power distance tend to have a lower impact of ownership concentration on the level of FLID, whereas countries with higher masculinity tend to have a lesser positive relationship between gender diversity and the level of FLID.

Notwithstanding, this study provides novel and persuasive evidence regarding the effects of firm- and country-specific characteristics as possible determinants of forward-looking disclosures, drawing on evidence from international companies with free floats, boards with female quotas and cultural values including masculinity and long-term orientation. This work offers unique insights from the upper echelons lens, which implies that firms need to obtain a critical mass of gender diversity to achieve a more balanced forward-looking perspective on their annual reports.

This study aims to examine the under-researched relationship between audit committee independence and earnings management in a number of emerging Middle Eastern and North African (MENA) countries.

Ordinary least squares regression was used to study the association between audit committee independence and earnings management in a sample of 3,206 firm-year observations during the years 2007–2017. Data were obtained from the Thomson Reuters Compustat database.

The main results show that audit committee independence has a negative association with accrual-based earnings management. The results also document no evidence to suggest that audit committee independence has any significant relationship with real earnings management.

This study provides new evidence of the impact of the independence of the audit committee in decreasing earnings management in MENA region, which was not addressed in previous studies.

This study has a significant practical implication for regulators and corporate governance policymakers in MENA countries and other countries with a similar institutional setting, whose responsibility is to prescribe proper corporate governance structures to guarantee that shareholders are protected.

The author contributes to the still limited research on the impact of audit committee independence on earnings management since the extant literature focuses on the Anglo-Saxon countries. The author tries to provide new insights into this relationship within the developing context, the case of MENA countries that have a different environment compared to advanced markets. To the best of the author’s knowledge, this study is among the pioneering efforts to investigate the influence of audit committee independence on earnings management in MENA countries.