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41.
Let Δ be a simplicial complex and χ be an s-coloring of Δ. Biermann and Van Tuyl have introduced the simplicial complex Δχ. As a corollary of Theorems 5 and 7 in their 2013 article, we obtain that the Stanley–Reisner ring of Δχ over a field is Cohen–Macaulay. In this note, we generalize this corollary by proving that the Stanley–Reisner ideal of Δχ over a field is set-theoretic complete intersection. This also generalizes a result of Macchia.  相似文献   
42.
In this study, the density functional theory computational method is used to investigate the encapsulation process of metformin into three types of the cyclic peptides composed of eight serine (CP1), eight glycine (CP2), and four serine‐glycine (CP3) cyclic peptides as a new model in the process of drug delivery in the gas phase. The obtained results using the B3LYP/6‐31++G (d,p) method indicate that the complexes formed are energetically favored. Furthermore, results reveal that the drug encapsulation process is typically chemisorption. The natural bonding orbital analysis shows that the intermolecular interaction of the C2 complex (metformin/CP2) is stronger than the C1 (Metformin/CP1) and C3 (Metformin/CP3) complexes due to greater total charge transfer energy, and the C1 complex is found to be the most favored complex. The theory of atoms in molecule (AIM) method is used to analyze the nature of interactions in different molecular systems. The results show the investigated cyclic peptides as effective carriers of metformin in the nanomedicine field.  相似文献   
43.
Abstract  Electrochemical oxidation of 2,3-dimethylhydroquinone has been studied in the presence of β-diketones as nucleophiles in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results indicate that the derivatives of 2,3-dimethylhydroquinone participate in a Michael addition reaction to form the corresponding benzofuran derivatives. The electrochemical synthesis has been successfully performed at pH 7.0 and E = 0.1 V versus an Ag|AgCl|KCl (3 M) in an undivided cell in good yield and purity. Graphical Abstract     相似文献   
44.

Abstract  

Electrochemical oxidation of 2,3-dimethylhydroquinone has been studied in the presence of β-diketones as nucleophiles in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The results indicate that the derivatives of 2,3-dimethylhydroquinone participate in a Michael addition reaction to form the corresponding benzofuran derivatives. The electrochemical synthesis has been successfully performed at pH 7.0 and E = 0.1 V versus an Ag|AgCl|KCl (3 M) in an undivided cell in good yield and purity.  相似文献   
45.
Recently, Haghighi, Terai, Yassemi, and Zaare-Nahandi introduced the notion of a sequentially (S r ) simplicial complex. This notion gives a generalization of two properties for simplicial complexes: being sequentially Cohen–Macaulay and satisfying Serre’s condition (S r ). Let Δ be a (d?1)-dimensional simplicial complex with Γ(Δ) as its algebraic shifting. Also let (h i,j (Δ))0≤jid be the h-triangle of Δ and (h i,j (Γ(Δ)))0≤jid be the h-triangle of Γ(Δ). In this paper, it is shown that for a Δ being sequentially (S r ) and for every i and j with 0≤jir?1, the equality h i,j (Δ)=h i,j (Γ(Δ)) holds true.  相似文献   
46.
Let ${\mathbb{K}}$ be a field and ${S = \mathbb{K}[x_1,\dots,x_n]}$ be the polynomial ring in n variables over the field ${\mathbb{K}}$ . In this paper, it is shown that Stanley’s conjecture holds for I and S/I if I is a product of monomial prime ideals or I is a high enough power of a polymatroidal or a stable ideal generated in a single degree.  相似文献   
47.

Abstract  

In this study, we present a convenient and efficient method for the synthesis of novel, highly substituted 2-vinyl furans using a three-component reaction. The zwitterions generated from the reaction of isocyanides and dialkyl acetylenedicarboxylates are reacted with trans-cinnamoyl chlorides to produce the desired products in good yields.  相似文献   
48.
A novel atom economical diastereoselective synthesis of 5-iminooxazolines and their subsequent transformation to α,α-disubstituted dipeptide esters is described. Heating a mixture of cyclohexyl isocyanide and Z-α-benzoyl amino-acrylic acid alkyl esters under solvent-free conditions, afforded 5-iminooxazolines, which, upon specifications provided α,α-disubstituted dipeptide esters in good yield.  相似文献   
49.
In this work, two-step hollow fiber-based liquid-phase microextraction procedure was evaluated for extraction of the zwitterionic cetirizine (CTZ) and basic hydroxyzine (HZ) in human plasma. In the first step of extraction, the pH of sample was adjusted at 5.0 in order to promote liquid-phase microextraction of the zwitterionic CTZ. In the second step, the pH of sample was increased up to 11.0 for extraction of basic HZ. In this procedure, the extraction times for the first and the second steps were 30 and 20 min, respectively. Owing to the high ratio between the volumes of donor phase and acceptor phase, CTZ and HZ were enriched by factors of 280 and 355, respectively. The linearity of the analytical method was investigated for both compounds in the range of 10-500 ng mL(-1) (R(2) > 0.999). Limit of quantification (S/N = 10) for CTZ and HZ was 10 ng mL(-1) , while the limit of detection was 3 ng mL(-1) for both compounds at a signal to noise ratio of 3:1. Intraday and interday relative standard deviations (RSDs, n = 6) were in the range of 6.5-16.2%. This procedure enabled CTZ and HZ to be analyzed simultaneously by capillary electrophoresis.  相似文献   
50.
In this paper the lattice Boltzmann method (LBM) is employed to simulate deformation and breakup of a falling drop under gravity. First the two-phase LBM is applied to verify the Laplace law for static drops. In order to further verify the model, relaxation of a square droplet with two different viscosities is conducted. Then deformation and breakup of a falling drop for some range of Eotvos and Ohnesorge numbers are investigated. It is seen that at relatively low Eotvos numbers, where the surface tension force is dominant, the drop deforms slowly and reaches a steady state without breakup. At higher Eotvos numbers gravitational force prevail over the surface tension force and the drop distorts more. Breakup of the drop can be seen for a large enough Eotvos value. On the other hand the stabilizing effect of the Ohnesorge number, which is the ratio of viscous stresses and surface tension, is shown. It is found that at higher Ohnesorge values, the viscous forces are dominant and the drop tends to maintain its original shape.  相似文献   
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