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Binary bismuth sulfide (Bi2S3) and ternary aluminum-doped bismuth sulfide (Al@Bi2S3) thin films were prepared by the chemical bath deposition method for photovoltaic applications. The newly designed materials synthesized at room temperature were thoroughly analyzed by several characterization techniques i.e., X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, optical absorption, thickness measurement, and Hall effect techniques. Correlation between structural, morphological, optical, electrical, and transport properties was evaluated. The parent material i.e., Bi2S3 is reported to have an orthorhombic phase, while doped derivatives revealed the amorphous phase. Optical band gaps in the range of 1.6–1.3 eV and absorption coefficients were found in the range of 104 to 106 cm−1. The thickness of the films changed with the change in the composition of the solution matrix and the films were well adhered, compact, and crack free. Hall measurements show that the dominant carriers in all studied compounds were electrons and that the carrier density for ternary films is almost two orders of magnitude greater than binary Bi2S3. The disorderliness in these newly designed materials is traced through the estimation of the change in the Urbach energy. [ABSTRACT FROM AUTHOR]

In this article, we present the continuity analysis of the 3D models produced by the tensor product scheme of (m + 1) -point binary refinement scheme. We use differences and divided differences of the bivariate refinement scheme to analyze its smoothness. The C 0 , C 1 and C 2 continuity of the general bivariate scheme is analyzed in our approach. This gives us some simple conditions in the form of arithmetic expressions and inequalities. These conditions require the mask and the complexity of the given refinement scheme to analyze its smoothness. Moreover, we perform several experiments by using these conditions on established schemes to verify the correctness of our approach. These experiments show that our results are easy to implement and are applicable for both interpolatory and approximating types of the schemes. [ABSTRACT FROM AUTHOR]

Families of parameter dependent univariate and bivariate subdivision schemes are presented in this paper. These families are new variants of the Lane-Riesenfeld algorithm. So the subdivision algorithms consist of both refining and smoothing steps. In refining step, we use the quartic B-spline based subdivision schemes. In smoothing step, we average the adjacent points. The bivariate schemes are the non-tensor product version of our univariate schemes. Moreover, for odd and even number of smoothing steps, we get the primal and dual schemes respectively. Higher regularity of the schemes can be achieved by increasing the number of smoothing steps. These schemes can be nicely generalized to contain local shape parameters that allow the user to adjust locally the shape of the limit curve/surface. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s10854-021-07154-0. Affiliation of Dr. Ahmad Nauman Shah Saqib incorrectly written as "Department of Chemistry, Education University-Attock Campus (EU) Attock, Sargodha, Pakistan" is changed to "Department of Chemistry, University of Education Lahore, Attock campus, Attock-43600, Pakistan". [Extracted from the article]

A complete set of NMR coupling constants (1JC-H, 2JC-H, 3JC-H, and 3JH-H) were calculated for the eight stereoisomers of quinic acid, at the B3LYP/6-311G(d,p)/PCM(methanol) level of theory. The Fermi contact term of the coupling constants was computed with a modified, uncontracted, version of the 6-311G(d,p) basis set, with additional tight polarization functions. 1H and 13C NMR chemical shifts were determined at the same level using the gauge-invariant atomic orbital (GIAO) method. The magnitude of the spin-spin coupling constants was found to be affected by the orientation (axial or equatorial) of the coupling proton and the orientation of the hydroxy group on the coupling carbon, whereas the chemical shifts depend on the presence or absence of electron-withdrawing hydroxy groups attached to the carbon atoms involved.Nuclear magnetic resonance coupling constants, computed with density functional theory, can be used to differentiate and identify the different stereoisomers of quinic acid. [ABSTRACT FROM AUTHOR]