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排序方式: 共有238条查询结果,搜索用时 62 毫秒
81.
A column generation approach is presented for the split delivery vehicle routing problem with large demand. Columns include route and delivery amount information. Pricing sub-problems are solved by a limited-search-with-bound algorithm. Feasible solutions are obtained iteratively by fixing one route once. Numerical experiments show better solutions than in the literature. 相似文献
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85.
Yasemin Yahsi Elif Gungor M. Burak Coban Hulya Kara 《Molecular Crystals and Liquid Crystals》2016,637(1):67-75
A new linear trinuclear MnIII-MnII-MnIII complex 1 has been synthesized and characterized by elemental, spectral, X-ray and magnetic analysis. X-ray diffraction studies show that the central MnII ion is located at a crystallographic inversion center and is triply bridged to the terminal MnIII ions through one methoxide, one syn-syn carboxylate and one hydroxyl oxygen bridges with the short MnIII…MnII distance that is 3.047 Å. The intermolecular C-H…O, C-H…π and ring-metal interactions are observed in the hydrogen-bonded assembly of 1. Magnetic studies reveal that the mixed-valence complex 1 has S = 3/2 ground state with antiferromagnetic exchange interactions between MnII and MnIII ions. 相似文献
86.
Gamze G
GER Ümmühan TÜRKYOLU Ezgi Nur GÜREN Süleyman YUR Abdullah Burak KARADUMAN Fatih G
GER Mehmet TEKN Gülmira
ZEK 《Turkish Journal of Chemistry》2021,45(2):387
In the present work, essential oil and fatty acids and extracts obtained from aerial parts of Phlomis linearis Boiss. & Bal. were investigated for chemical composition and biological activities. The phytochemical analyses were conducted with gas chromatography-mass spectrometry/flame ionisation detector (GC-MS/FID) and liquid chromatography-mass spectromtetry (LC-MS/MS) techniques. The extracts and essential oil were studied for α-amylase and acetylcholinesterase activities with two different spectrophotometric methods. Antimicrobial activities of the extracts were investigated by microdilution. The extracts were evaluated in vitro for cytotoxic effects against cancer and normal cell lines by MTT assay. The essential oil (EO) contained α-pinene (12.5%) and β-caryophyllene (10.7%) as main compounds. Palmitic (26.5%) and nonadecanoic acids (26.6%) were determined as fatty acids. Phytochemical analysis of the extracts found phenolic acids, phlinosides, verbascoside, and flavonoids. The extracts and essential oil demonstrated poor α-amylase inhibitory activity. The best acetylcholinesterase inhibitory activity was obtained for diethly ether extract of P. linearis (67.2 ± 3.4%) at 10 mg /mL concentration. Ethyl acetate extract found to be effective against Staphlococcus aureus at a minimum inhibitory concentration (MIC) of 156.26 µg/mL. Diethyl ether extract of P. linearis was active on A549 cell lines with an IC50 = 316 ± 4.16 µg/mL when compared with cisplatin IC50 = 24.43 ± 0.14 µg/mL. To the best of our knowledge, the present work is the first comprehensive report on anti-acetylcholinesterase, anti-α-amylase, and antimicrobial activities, as well as cytotoxic effects of P. linearis. 相似文献
87.
Songul Ulag Elif Ilhan Ramazan Demirhan Ali Sahin Betul Karademir Yilmaz Burak Aksu Mustafa Sengor Denisa Ficai Aurel Mihail Titu Anton Ficai Oguzhan Gunduz 《Molecules (Basel, Switzerland)》2021,26(9)
In this research, polyvinyl-alcohol (PVA)/gelatin (GEL)/propolis (Ps) biocompatible nanofiber patches were fabricated via electrospinning technique. The controlled release of Propolis, surface wettability behaviors, antimicrobial activities against the S. aureus and P. aeruginosa, and biocompatibility properties with the mesenchymal stem cells (MSCs) were investigated in detail. By adding 0.5, 1, and 3 wt.% GEL into the 13 wt.% PVA, the morphological and mechanical results suggested that 13 wt.% PVA/0.5 wt.% GEL patch can be an ideal matrix for 3 and 5 wt.% propolis addition. Morphological results revealed that the diameters of the electrospun nanofiber patches were increased with GEL (from 290 nm to 400 nm) and Ps addition and crosslinking process cause the formation of thicker nanofibers. The tensile strength and elongation at break enhancement were also determined for 13 wt.% PVA/0.5 wt.% GEL/3 wt.% Ps patch. Propolis was released quickly in the first hour and arrived at a plateau. Cell culture and contact angle results confirmed that the 3 wt.% addition of propolis reinforced mesenchymal stem cell proliferation and wettability properties of the patches. The antimicrobial activity demonstrated that propolis loaded patches had antibacterial activity against the S. aureus, but for P. aeruginosa, more studies should be performed. 相似文献
88.
Mete?Burak?Calci Huanyin?Chen Sait?HaliciogluEmail author Abdullah?Harmanci 《Mediterranean Journal of Mathematics》2017,14(3):137
Let R be a ring with identity and J(R) denote the Jacobson radical of R. A ring R is called J-reversible if for any a, \(b \in R\), \(ab = 0\) implies \(ba \in J(R)\). In this paper, we give some properties of J-reversible rings. We prove that some results of reversible rings can be extended to J-reversible rings for this general setting. We show that J-quasipolar rings, local rings, semicommutative rings, central reversible rings and weakly reversible rings are J-reversible. As an application it is shown that every J-clean ring is directly finite. 相似文献
89.
Burak ?ekero?lu Fatma Ta?delen 《Journal of Mathematical Analysis and Applications》2007,326(2):896-907
Almost four decades ago, Konhauser introduced and studied a pair of biorthogonal polynomials
90.
A variational formulation of boundary-value problems of the non-linear dynamic theory of elasticity using the Hamilton functional is presented. The quasi-static boundary-value problem for thin plates is considered. The initial system of equations, in a two-dimenonal formulation, is represented in terms of generalized forces and displacements. The sufficient conditions for the existence and uniqueness of a weak solution are established. 相似文献