introduction: the aim of this study was to evaluate and compare microhybride composite treated by bur and different power of erbium, chromium doped yttrium scandium gallium garnet (er,cr:ysgg) laser by scanning electron microscope (sem). methods: 21 microhybride composite blocks (diafil tm, diadent, korea) with 2 × 4 × 4 mm dimensions were made. the bonding surface of these blocks were polished...

density-functional-based and ab initio calculations were implemented at different computational levels to estimate the binding energy of zn2+ ion adsorbed on the available sites of a silicate mel-type adsorbent. b3lyp and mp2 were used in combination with the 6-31g*, 6-31+g*, lanl2dz, 6-311+g*, and def2-tzvp basis sets. the zinc cation was found to preferentially occupy the 6mr sites followed b...

ab initio calculations at hf/6-31g* level of theory for geometry optimization and mp2/6-31g*//hf/6-31g*for total energy calculation are reported for z-cyclooctene (1). the most favorable conformation of 1 is theunsymmetric boat-chair (1-bc) geometry. potential energy profiles for two different boat-chair/boat-chairinterconversion processes were calculated. the process via a chair transition sta...

: In this work, different levels of theory containing HF, B3LYP, and MP2 with different basis sets such as 6-31G, 6-31G*, 6-311G, 6-311+G, 6-31+G*, 6-31+G are used to predict relative acidity constants of some aniline derivatives. Three different kinds of radii containing UAHF, Bondi, and Pauling are used to study how cavity forms change acidity constants. In all cases, DPCM model is used to si...

for a simple digraph $g$ of order $n$ with vertex set${v_1,v_2,ldots, v_n}$, let $d_i^+$ and $d_i^-$ denote theout-degree and in-degree of a vertex $v_i$ in $g$, respectively. let$d^+(g)=diag(d_1^+,d_2^+,ldots,d_n^+)$ and$d^-(g)=diag(d_1^-,d_2^-,ldots,d_n^-)$. in this paper we introduce$widetilde{sl}(g)=widetilde{d}(g)-s(g)$ to be a new kind of skewlaplacian matrix of $g$, where $widetilde{d}(g...

some of the adamantane properties were calculated in this study. chemical shift, free energy ofsolvation, free energy of cavity formation, henry's law constant, and other properties ofadamantane in dry phase, three solvents and three temperatures have been calculated with abinitio method base on density functional theory (dft) at b3lyp/6-31g, b31yp/6-31g*, b3lyp/6-31+g* and b3lyp/6-31++g** leve...

objective(s): the energy resolution of a cadmium-zinc-telluride (czt) solid-state semiconductor detector is about 5%, and is superior to the resolution of the conventional anger type detector which is 10%. also, the window width of the high-energy part and of the low-energy part of a photo peak window can be changed separately. in this study, we used a semiconductor detector and examined the ef...