•Effects of thickness and annealing conditions on ZnO thin film properties have been studied.•Thicker and annealed samples under shock thermal had better quality, better crystallization, and lower ...grain size.•High transmittance and lower resistivity have been recorded for thicker and annealed samples under shock thermal.
This work aims to study the influence of shock/ gradual annealing temperature on the properties of ZnO thin film with different film thickness. ZnO thin films have been prepared on glass substrates using a sol-gel method deposing by dip-coating technique. Zinc acetate dihydrate, monoethanolamine, and 2-methoxyethanol were used as starting materials, stabilizer, and solvent respectively. The X-ray diffraction patterns show that all films have the wurtzite structure and the (002) diffraction peak dominated in all of them. The ZnO films with a higher thickness and annealed under thermal shock, show higher peaks intensity and lower grain size compared to the films annealed by gradually increasing temperature. Scanning electron microscopy images confirmed the results of DRX. The best electrical and optical properties have been obtained for the samples with higher thicknesses and annealed by heat shock. ZnO thin films show a resistance value of 1,296 Ω.cm and a band gap value of 3.245 eV with high transmittance (>90%).
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•Effect of crystallite nano-size on the gap energy Eg of ZnO nanopowders.•Effect of crystallite nano-size on the varistor properties.•Effect of Ga-doping on the crystallite size of ZnO ...nanopowders.•Effect of Ga-doping on the linear and nonlinear regions of (I-V)of the ZnO varistor.•The high resistance region in the linear region,also known as the "Ohmic region'.•The non-linear region is expanded, and the ability to discharge impulsive currents is greatly enhanced.
Nanostructured ZnO has received a considerable amount of interest, owing to its unique physical and chemical characteristics, as well as its remarkable performance in the fields of electronics, optics, and photonics. This work aims to study the influence of Ga dopant on the structural, optical, and electrical properties of ZnO nanopowders. Undoped and Ga-doped ZnO (GZO) nanopowders were successfully synthesised with the soft chemical sol-gel method. The solution was prepared using zinc acetate dihydrate and gallium (III) nitrate hydrate as precursors. The ethylene glycol is used as solvent. The X-ray diffractometer, scanning electronic microscope (SEM), UV–Vis, FTIR, and four-point probe method are used to analyse the properties of the synthesised powders. XRD and FTIR measurements show the growth of pure and Ga-doped ZnO crystals, which have a hexagonal wurtzite structure, and the average crystallite size varies from 9.09 nm to 24.8 nm. The nanospherical morphology of the nanopowders synthesised can be seen in the SEM images. The UV–visible spectroscopy shows that the optical gap energy increases with Ga concentration, from 3.59 eV to 3.67 eV. The I-V electrical measurements indicate that the breakdown voltage and the non-linear coefficient increase with Ga doping. This study will open the way for the investigation of a relationship between the electrical and nanostructural features of ZnO-based varistors for future device applications.
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Two-dimensional seismic data and well data from the Sbiba graben in central Tunisia (North Africa) reveal its asymmetrical structural geometry affected by E–W, N–S, NW–SE, and NE–SW master ...strike-slip faults. These faults have been intruded by Upper Triassic evaporites, which can be classified into the following three types: (1) sealed evaporite anticlines and domes along folded structures; (2) extrusional wrinkles of “salt walls” at the borders of the graben related to along-strike displacement of the master fault zone; and (3) evaporite outpouring at the center of the graben interpreted as the result of fault and diapir movement. Detailed seismic-stratigraphic analysis highlights a complex interplay between fault growth and evaporite movement, which strongly controlled the evolution of the graben. During the Mesozoic, tectonic stresses induced multidirectional faulting along inherited faults. The vertical rising of the Upper Triassic evaporites was initiated locally at the intersection of master faults during regional extensional and transtensional events in the sub-evaporite basement. The interaction of normal faulting and evaporite diapirism caused lateral outpouring of surface-piercing evaporites. This phenomenon is well expressed in Upper Cretaceous (upper Cenomanian to lower Turonian) strata. The master faults, which cut the diapir at the border and the crest, have caused the extrusion of evaporites. The downward, gravity-driven flow of these evaporites across the slope surface and subsequent accumulation and preservation in Mesozoic sediments is related to the fault escarpment and the adjacent fault-induced depression. There is an apparent relation between tectonic inheritance and inversions of the graben, where interconnected deep faults and diapirs have been reactivated during extensional and contractional tectonic episodes, causing evolution of the structures with the associated sedimentary lapouts. Several autochthonous Triassic evaporites and associated fault escarpments have induced salt canopy structures.
•The work highlights new structural framework of salt-influenced grabens in Tunisia.•Sealed Salt anticlines, extrusional wrinkles and salt outpouring were identified.•Growth faults junction in the basement induced its vertical rising and outpouring.•Evaporite downward flow related to fault escarpment and fault-induced depression.•Salt canopy structures were highlighted in lozengy depocenters of Tunisia.
The article contains the results of the analysis of the world’s scientific achievements and theoretical generalizations regarding the functions of ethics in business organizations, the range of its ...application in management, and its role and place in ensuring the effectiveness of the company’s economic activity. This study considers ethics not as an obstacle to business development that requires additional resources but as a relationship based on trust and cooperation that determines the firm’s strategy and competitive advantages. The article summarizes approaches to integrating ethics into management practice and considers the taxonomy of management ethics in organizations. Using the example of a family business, the article identifies general mechanisms for reconciling ethical principles and economic efficiency of a company so that care about ethical responsibility has a favorable impact on fulfilling the main mission – making a profit. The ethical practices of family and non-family businesses are compared. Although family businesses do not always have a formal code of ethics, they are more likely to model ethical behaviour through their actions; family values and their transmission from generation to generation play a significant role in shaping ethical practices in this business; family businesses become more involved in social activities and feel responsible to the community; their image and reputation are an absolute priority. Based on the theory of legitimacy, the article examines the concept of socio-emotional wealth using the example of the family business, which includes values related to emotions and non-financial aspects of business that meet the emotional needs of the family (identity, ability to influence the family and perpetuate the family dynasty). The article considers ethics an integral element of a company’s social capital. It summarizes the approaches and stages of ethical policy formation, through which ethical standards are specified and implemented through formal and informal rules and procedures established by individuals and organizations. While forming an ethical policy, it is important to start from the components of the company’s context (culture, values, internal regulations), choose a business model that is consistent with values and ethical principles, and formalize the procedures for the transition from individual ethical behaviour of managers (loyalty, honesty, ethics, fidelity) to the creation of collective ethics (dissemination of these values within the company). The article provides recommendations for the successful integration of ethical policy: coordination between ethics and corporate image, between ethics and company performance, and coordination of mechanisms for formalizing ethics and corporate culture.
The morphology, internal architecture, and emplacement mechanisms of the Central Atlantic Magmatic Province (CAMP) lava flows of the Hartford and Deerfield basins (USA) are presented. The Talcott, ...Holyoke, and Hampden formations within the Hartford basin constitute distinct basaltic units, each exhibiting chemical, mineralogical, and structural differences corresponding to flow fields. Each flow field was the result of several sustained eruptions that produced both inflated pahoehoe flows and subaquatic extrusions: 1–5 eruptions in the Talcott formation and 1–2 in Holyoke and Hampden basalts, where simple flows are dominant. The Deerfield basin displays the Deerfield basalt unit, characterized by pillow lavas and sheet lobes, aligning chemically and mineralogically with the Holyoke basalt unit. Overall, the studied flow fields are composed of thick, simple pahoehoe flows that display the entire range of pahoehoe morphology, including inflated lobes. The three-partite structure of sheet lobes, vertical distribution of vesicles, and segregation structures are typical. The characteristics of the volcanic pile suggest slow emplacement during sustained eruptive episodes and are compatible with a continental basaltic succession facies model. The studied CAMP basalts of the eastern United States are correlated with the well-exposed examples on both sides of the Atlantic Ocean (Canada, Portugal, and Morocco).
Climate Change (CC) is a major issue of our century. Controlling the constraints of Greenhouse Gas (GHG) emissions through transformation into opportunities, in an organization to increase industrial ...production, has become a necessity. The main reason for this adoption was the effectiveness of energy management and responsible linkages that are being developed to determine the issues and opportunities of carbon finance for organizations. Through analysis of the European Union Emissions Trading Scheme (EU ETS) and the Clean Development Mechanism (CDM), this article presents and determinate the variables that influence the performance of the strategies of EU ETS players via the EUA allowances. Our study focuses on price changes in the EUA, being the most liquid carbon asset. In this regard, we highlighted the daily spot price of the EUA to highlight the daily changes affecting this price, given the high volatility in this Carbon financial market. The treatments of the determinants of CO2 prices (EUA) can be used to analyze the evolving and expanding carbon financial markets sphere. It features stylized facts about carbon financial markets from an economics and management perspective, as well as covering key aspects of pricing strategies (institutional decisions, energy prices and extreme weather events), climate change mitigation. Aimed at those with technical analysis, the CO2 prices within the framework of the EU ETS depend on several determinants. This paper constitutes an introduction to emission trading and an overview of the regulations governing Carbon financial markets. First, we detail the price changes in the EUA and primary energy prices. Second, we introduce the main characteristics of emissions trading, be it in terms of spatial and temporal limits, Clean Dark Spread, Clean Spark Spread and Switch Price. Third, we provide a technical analysis of atmospheric variables, structural variations and the Sanitary COVID-19 crisis and their impacts in the price development of EU CO2 allowances and presnt after conclusion some implications for future.
Here we describe the new, rich lacustrine paleontological and archeological site of Wadi Sarrat (Le Kef, northeastern Tunisia), dated to the beginning of the Middle Pleistocene, ∼0.7 Ma, by a ...combination of paleomagnetism and biochronology. This locality preserves the earliest record of auroch, Bos primigenius, the ancestor of the worldwide extant domestic cattle species Bos taurus, which is represented by a nearly complete, giant-sized cranium (specimen OS1). Both the cranial anatomy and the size of this specimen reflect the phylogenetic legacy inherited from its ancestor, the late Early Pleistocene African Bos buiaensis, recorded in the eastern African paleoanthropological site of Buia, Eritrea (1.0 Ma). Given that the latter species is an evolved form of the classical Early Pleistocene African buffalo Pelorovis oldowayensis, the finding of B. primigenius at Wadi Sarrat shows that the genus Bos evolved in Africa and dispersed into Eurasia at the beginning of the Middle Pleistocene, which coincides with the spread of the Acheulian technocomplex in northern Africa and Europe. Therefore, the lineage of Pelorovis-Bos has been part of the human ecological landscape since the appearance of the genus Homo in the African Early Pleistocene.
Tunisia is one of the North African countries, geographically situated in a central position at the crossroad between Africa and Europe. The demographic features of the Tunisian population include ...among others high rates of consanguinity. We report, here on the spectrum of genetic diseases in Tunisia. The review of the literature, including other available information (gray literature) showed that there are at least 346 genetic disorders for which cases have been identified in the Tunisian population. Among these, 62.9% are autosomal recessive, 23% autosomal dominant, 5.4% X-linked, and the remaining are of Y-linked, mitochondrial, and unknown mode of transmission. Fifty percent of the reported conditions in this study are caused by at least one mutation. For autosomal recessive diseases, most of the mutations were identified at homozygous state among the affected individuals. Part of the mutations was the result of a founder effect; these are the consequences of the high rate of consanguinity. The congenital malformations, diseases of the nervous system and metabolic disorders are the major groups of genetic diseases affecting the Tunisian population. The large spectrum of diseases and their relatively high frequency could be explained by the high degree of inbreeding and the presence of multiple mutations, either allelic or in different genes. This is due to the richness of the genetic background of the studied population. A multidisciplinary approach is essential to develop adequate preventive programmes adapted to the social, cultural, and economic context.
Fanconi anemia (FA) is a rare autosomal recessive disease characterized by progressive pancytopenia, congenital malformations, and predisposition to acute myeloid leukemia. Fanconi anemia is ...genetically heterogeneous, with at least eight distinct complementation groups of FA (A, B, C, D1, D2, E, F, and G) having been defined by somatic cell fusion studies. Six genes (FANCA, FANCC, FANCD2, FANCE, FANCG, and FANCF) have been cloned. Mutations of the seventh Fanconi anemia gene, BRCA2, have been shown to lead to FAD1 and probably FAB groups. In order to characterize the molecular defects underlying FA in Tunisia, 39 families were genotyped with microsatellite markers linked to known FA gene. Haplotype analysis and homozygosity mapping assigned 43 patients belonging to 34 families to the FAA group, whereas one family was probably not linked to the FANCA gene or to any known FA genes. For patients belonging to the FAA group, screening for mutations revealed four novel mutations: two small homozygous deletions 1693delT and 1751-1754del, which occurred in exon 17 and exon 19, respectively, and two transitions, viz., 513G-->A in exon 5 and A-->G at position 166 (IVS24+166A-->G) of intron 24. Two new polymorphisms were also identified in intron 24 (IVS24-5G/A and IVS24-6C/G).
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