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The relationship between digitalization, CO 2 emissions, and financial development
Get PDFThis paper first examines the relationship between digitalization and CO 2 emissions to test the inverted U-shaped relationship predicted by the Environmental Kuznets Hypothesis. The results using the fixed effects, two-stage least squares, and generalized method of moments estimation coincide with this inverted U-shaped relationship suggesting that increases in digitalization increase CO 2 emissions up to a certain threshold of digitalization and then decrease it. An interaction term with financial development was then included in the model to determine the role that it plays in this inverted U-shaped relationship. Overall, results indicated that there is no strong evidence that financial development plays a role in the relationship between digitalization and CO 2 emissions. Since the nature of the relationship depends on the level of digital development of a country, this suggests that countries should have different policies when attempting to reduce emissions as they continue to digitalize
Chemometrics and Spectroscopic Analyses of Peganum harmala Plant’s Seeds by Laser‐Induced Breakdown Spectroscopy
Get PDFIn the present work, the rapid identification of elements and their relative chemical com‐ position in various Peganum harmala seed samples were investigated using a calibration‐free laser‐ induced breakdown spectroscopy technique (CF‐LIBS). A pulsed Nd:YAG laser‐source with a 5 ns pulse‐duration, and 10 Hz pulse repetition rates providing 400 and 200 mJ energy at 1064 and 532 nm wavelength, respectively, was focused on the Peganum harmala seed samples for ablation. A LIBS 2000+ spectrometer within the wavelength range (200 to 720 nm), emission‐spectra were recorded. The measured spectra of the Peganum harmala sample gives spectral lines of Carbon (C), Magnesium (Mg), Lithium (Li), Sodium (Na), Calcium (Ca), Silicon (Si), Iron (Fe), Strontium (Sr), Copper (Cu), Potassium (K), and Lead (Pb). A CF‐LIBS technique has been employed for the compositional study of the elements exist in the Peganum harmala seed samples. The measured results demonstrate that C, Mg, and Ca are found to be major elements in the Peganum harmala seed samples with composi‐ tions of ~36.64%, ~24.09%, and ~19.03%, respectively. Along with the major elements, the elements including Li, Na, Si, K, Fe, and Sr were identified as minor elements with compositions of ~2.87%, ~2.33%, ~3.72%, ~7.17%, ~2.83%, and ~1.14%, respectively. Besides Cu (~8.07 μg/g), and Pb (~1.10 μg/g) elements were observed as trace elements exist in the Peganum harmala seed samples. Further‐ more, the electron number density including the plasma excitation‐temperature were calculated using the stark‐broadening line profile method and the Saha–Boltzmann plot method, respectively. The plasma parameters versus laser‐irradiance and the distance from the sample were further in‐ vestigated. Moreover, a principal component analysis (PCA) method was also utilized to the spec‐ tral data obtained by using LIBS to discriminate various seed samples with four classes, namely, α, β, γ, and Δ. Three principal‐components (PCs) calculated from eigenvalues of score matrix de‐ scribed 87.6%, 4.6%, and 2.5% of total variance for PC1, PC2, and PC3, respectively. The LIBS spec‐ tral data variance covered by the initial 3 PCS was found as ~94.7% of total variance. The PCA results have successfully demonstrated the different classes of the Peganum harmala seed samples based on the different doping compositional ratios of the Zn element. This study confirmed the feasibility and ability of LIBS and PCA for the rapid analysis of Peganum harmala seed samples. Finally, the results achieved using CF‐LIBS were incorporated with those obtained from the XRF and EDX an‐ alytical techniques
