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1.
In this paper, we prove some existence results for the Webster scalar curvature problem on the three dimensional CR compact manifolds locally conformally CR equivalent to the unit sphere S3 of C2. Our methods are based on the techniques related to the theory of critical points at infinity.  相似文献   
2.
An easily reproducible protocol allowing inter- or intramolecular spirocyclization on β-dicarbonyl structures is described. This methodology could afford a wide variety of spirocyclic pharmacophores. As examples, highly substituted spirobenzophenanthridin-6(5H)-ones and spirolactones were synthesized. These scaffolds could be used for the design of many compounds exhibiting biological activities.  相似文献   
3.
Krichen  Firas  Walha  Siwar  Kabadou  Ahlem 《Crystallography Reports》2017,62(7):1152-1156
Crystallography Reports - A new mixed-valence coordination polymer [Cu3(SCN)4(DMSO)2] n (SCN– = thiocyanato and DMSO = dimethyl sulfoxide) was prepared and characterized by single crystal...  相似文献   
4.
Operators T that belong to some summing operator ideal can be characterized by means of the continuity of an associated tensor operator \({\overline{T}}\) that is defined between tensor products of sequences spaces. In this paper, we provide a unifying treatment of these tensor product characterizations of summing operators. We work in the more general frame provided by homogeneous polynomials, where an associated “tensor” polynomial—which plays the role of \({\overline{T}}\)—, needs to be determined first. Examples of applications are shown.  相似文献   
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6.
This article proposes a new fractional-order discrete-time chaotic system, without equilibria, included two quadratic nonlinearities terms. The dynamics of this system were experimentally investigated via bifurcation diagrams and largest Lyapunov exponent. Besides, some chaotic tests such as the 0–1 test and approximate entropy (ApEn) were included to detect the performance of our numerical results. Furthermore, a valid control method of stabilization is introduced to regulate the proposed system in such a way as to force all its states to adaptively tend toward the equilibrium point at zero. All theoretical findings in this work have been verified numerically using MATLAB software package.  相似文献   
7.
The synthesis of new unsaturated N-sulfonylcarbamates by the addition of unsaturated alcohols to aroxy(alkoxy)sulfonylisocyanates is reported. The reaction is carried out at room temperature in the presence or absence of solvent, depending on the nature of the starting alcohol. The products were obtained in good yields and characterized with IR, 1H, and 13C NMR and HRMS analyses.  相似文献   
8.
A three step synthesis of various thiobarbiturate derivatives 17-24 was established. The first step is mediated by Mn(OAc)?, in order to generate a carbon-carbon bond between a terminal alkene and malonate. Derivatives 1-8 were obtained in moderate to good yields under mild conditions. This key step allows synthesis of a wide variety of lipophilic thiobarbiturates, which could be tested for their anticonvulsive or anesthesic potential.  相似文献   
9.
Brassica oleracea L. var. capitata f. rubra (Red Cabbage) dye is composed mainly of natural pigment called anthocyanins used as a natural colourant. Wool and silk fibres were dyed with the aqueous extract obtained from red cabbage. The dyeing process was investigated and the combined effects of dyeing conditions on the colour yield parameter (K/S) were studied. Resulted fastness to wash, rubbing and light of the dyed fabrics were evaluated. Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD5) of the residual effluent were measured. Best dyeing conditions were found to be: 50 g/100 mL, pH 2, 60 min and 100 °C, respectively, for the red cabbage weight, pH, dyeing duration and temperature. Good fastnesses properties were found in both cases: for wool and silk fabrics. It was found also that the calculated biodegradability ratio (COD/BOD5) of the residual bath of dyeing wool and silk with red cabbage extract are lower than 1.5 which means that these baths are biodegradable.  相似文献   
10.
Structural Chemistry - CHK1 is a promising molecular target that gained immense attention recently for the development of cancer therapeutics. In this study, a simulation-based investigation was...  相似文献   
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