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31.
32.
The aim of the present paper is to define and study semi-slant \(\xi ^\perp \)-Riemannian submersions from Sasakian manifolds onto Riemannian manifolds as a generalization of anti-invariant \(\xi ^\perp \)-Riemannian submersions, semi-invariant \(\xi ^\perp \)-Riemannian submersions and slant Riemannian submersions. We obtain characterizations, investigate the geometry of foliations which arise from the definition of this new submersion. After we investigate the geometry of foliations, we obtain necessary and sufficient condition for base manifold to be a locally product manifold and proving new conditions to be totally umbilical and totally geodesicness, respectively. Moreover, some examples of such submersions are mentioned. 相似文献
33.
New bis(NHC)-Pd complexes were synthesized and characterized by elemental analysis, 1H NMR, 13C NMR, and IR spectroscopy. The reaction of Pd(OAc)2 and bis(benzimidazolium) salts in DMSO gave the monomeric palladium complex in which the N-heterocyclic carbene was bound to the metal centre. The crystal and molecular structure of the cis-dibromo{1,1′-di[2,3,4,5,6-pentamethylbenzyl]-3,3′-butylenedibenzimidazol-2,2′-diylidene}-palladium(II) complex was determined by single-crystal X-ray diffraction. The activity of the Pd(II) complexes in the direct arylation of benzothiazole with arylbromides was investigated. A preliminary catalytic study showed that these bis(NHC)-Pd complexes were highly active in the direct arylation of benzothiazole with arylbromides. 相似文献
34.
Shekhah O Arslan HK Chen K Schmittel M Maul R Wenzel W Wöll C 《Chemical communications (Cambridge, England)》2011,47(40):11210-11212
Thin films of MOFs grown on solid substrates offer a huge potential with regard to tailoring the properties of a surface, in particular if used in connection with post-synthesis modification (PSM). Here, we report on the PSM of surface-supported crystalline MOFs, with target molecules using an amine-based coupling strategy. 相似文献
35.
A. Dilek Azaz Selma Celen Hilmi Namli Onur Turhan Raif Kurtaran Canan Kazak N. Burcu Arslan 《Transition Metal Chemistry》2007,32(7):884-888
A complex of NiII with 2,6-diacetylpyridinedihydrazone (L) towards nickel(II) has been prepared and characterized by means of elemental analyses,
IR, electronic spectra and single crystal X-ray analyses. [NiL2](NO3) was crystallized in the tetragonal space group P-4 21 c. The complex exhibits the expected coordination sphere with six
nitrogen atoms coordinated to the central NiII with a deformation from pseudo-octahedral geometry. Antimicrobial activities of the ligand and its complex were investigated. 相似文献
36.
In a recent paper, Chen and Ji [Chen, K., Ji, P., 2007. A mixed integer programming model for advanced planning and scheduling (APS). European Journal of Operational Research 181, 515–522] develop a mixed integer programming model for advanced planning and scheduling problem that considers capacity constraints and precedence relations between the operations. The orders require processing of several operations on eligible machines. The model presented in the above paper works for the case where each operation can be processed on only one machine. However, machine eligibility means that only a subset of machines are capable of processing a job and this subset may include more than one machine. We provide a general model for advanced planning and scheduling problems with machine eligibility. Our model can be used for problems where there are alternative machines that an operation can be assigned to. 相似文献
37.
Eray Arslan 《PAMM》2013,13(1):89-90
Two analytical models are developed for elastic multi-layered and functionally graded thick walled spherical pressure vessels subjected to uniform internal pressure. Simple and comprehensive recursive algorithms are proposed for the multi-layered vessel. In the model for functionally graded one, the modulus of elasticity is assumed to vary in radial direction according to a power law. Stress distributions of those vessels are compared and the results are presented in graphical form. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
38.
Dominik Jacob Kathrin Thüring Aurellia Galliot Virginie Marchand Adeline Galvanin Akif Ciftci Karin Scharmann Michael Stock Jean‐Yves Roignant Sebastian A. Leidel Yuri Motorin Raffael Schaffrath Roland Klassen Mark Helm 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(28):9666-9670
39.
The fabrication of nanoparticles has been perused as a topic of critical importance in the present decades. Biosynthesis of nanoparticles employs plants extract instead of harmful chemicals. These plant extracts act as reducing and capping agents which is the most appropriate and eco-friendly method among all the preparative routs. In present study, the magnetite nanoparticles (Fe3O4-NPs) were fabricated using rapid, single step and benign biosynthetic rout by reduction of ferric nitrate nonahydrate solution with Ferocactus echidne aqueous extract containing ascorbic acid as a main reducing and capping agent. The structural and morphological properties of prepared iron oxide nanoparticles were investigated by Powder X-ray diffraction and scanning electron microscopy. The size of the synthesized nanoparticles was approximately 15 ± 2 nm as determined by Scherrer equation. The biosynthetically fabricated nanoparticles were employed as catalyst for pyrolysis of nutshells to produce biofuel. Catalytic pyrolysis of biomass yields biofuel as an alternative source of energy and chemical feed stock. Effect of temperature, heating rate, and amount of catalyst were investigated on conversion percentage and product yields. Aniline point, carbon residue, and cetane number of prepared bio-oil were also determined. 相似文献
40.
Alp Arslan Kiraç 《Letters in Mathematical Physics》2008,83(2):149-161
Consider the Mathieu–Hill operator
in , where . We obtain the precise asymptotic formulas for the widths γ
k
of the instability intervals of L. The formula states the isolated terms of arbitrary number in the asymptotics of the sequence γ
k
for large k and verifies the results of Harrell (Am J Math suppl:139–150, 1981) and Avron and Simon (Ann Phys 134:76–84, 1981).
相似文献