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101.
102.
Journal of Solid State Electrochemistry - The motion of the ion pairs under the applied electric field is an important phenomenon in the storage properties of the capacitive devices. In this study,...  相似文献   
103.
We have demonstrated polarization insensitive AWGs by controlling the doping concentration of Boron in overcladding and the etching depth of waveguide. The proposed method uses the conventional fabrication process and does not degrade optical properties and reliability characteristics.  相似文献   
104.
Kinetic studies on nucleophilic substitution reaction of benzyl tosylates with anilines are reported. The reaction was found to proceed via a dissociative SN2 mechanism with less than 50 % bond formation and extensive bond breaking at the transition state. It was found that positive charge development at the benzylic carbon is substantial and para-substituent effect on the substrate is predominantly of resonance type. Bond formation is shown to be favored by a better nucleophile, by an electron withdrawing group on the substrate and by the more polar(higher MeCN content) solvent. The substrate, nucleophile and solvent were found to follow the RSP.  相似文献   
105.
The synthesis of six new [2+2] metallarectangles through the coordination‐driven self‐assembly of octahedral RuII‐based acceptors with ambidentate pyridyl‐carboxylate donors is described. These molecular rectangles are fully characterized by 1H NMR spectroscopy, high‐resolution electrospray mass spectrometry, and single‐crystal X‐ray diffraction. In each case, despite the possible formation of multiple isomers, based on the relative orientation of the pyridyl and carboxylate groups (head‐to‐head versus head‐to‐tail), evidence for the formation of a single preferred ensemble (head‐to‐tail) was found in the 1H NMR spectra. Furthermore, the cytotoxicities of all of the rectangles were established against A549 (lung), AGS (gastric), HCT‐15 (colon), and SK hep 1 (liver) human cancer cell lines. The cytotoxicities of rectangles that contained the 5,8‐dihydroxy‐1,4‐naphthaquinonato bridging moiety between the Ru centers ( 9 – 11 ) were particularly high against AGS cancer cells, with IC50 values that were comparable to that of reference drug cisplatin.  相似文献   
106.
Successive dialkylation of methyl acetoacetate with allylic functions 2 and 5, followed by oxidation, gave an α,β-unsaturated aldehyde 7. Intramolecular Michael addition of 7 to give a cyclopentanone 8, conversion to diester 9, and Krapcho decarbomethoxylation furnished methyl dl-jasmonate.  相似文献   
107.
Colony-stimulating factor 1 receptor (CSF1R, also known as c-FMS) is a receptor tyrosine kinase. Macrophage colony-stimulating factor (M-CSF) and IL-34 are ligands of CSF1R. CSF1R-mediated signaling is crucial for the survival, function, proliferation, and differentiation of myeloid lineage cells, including osteoclasts, monocytes/macrophages, microglia, Langerhans cells in the skin, and Paneth cells in the intestine. CSF1R also plays an important role in oocytes and trophoblastic cells in the female reproductive tract and in the maintenance and maturation of neural progenitor cells. Given that CSF1R is expressed in a wide range of myeloid cells, altered CSF1R signaling is implicated in inflammatory, neoplastic, and neurodegenerative diseases. Inhibiting CSF1R signaling through an inhibitory anti-CSF1R antibody or small molecule inhibitors that target the kinase activity of CSF1R has thus been a promising therapeutic strategy for those diseases. In this review, we cover the recent progress in our understanding of the various roles of CSF1R in osteoclasts and other myeloid cells, highlighting the therapeutic applications of CSF1R inhibitors in disease conditions.Subject terms: Osteoimmunology, Cell signalling, Targeted bone remodelling, Differentiation  相似文献   
108.
Interaction of a transition metal atom with defects in single-walled carbon nanotubes (SWNTs) were investigated through density functional theory calculations. For three kinds of intrinsic defects (single vacancies, double vacancies and Stone-Wales defects) in (5,5) armchair and (10,0) zigzag SWNTs, stable configurations were analyzed. The orientation of the specific bonds of the defects is related to the most stable configuration among several possible configurations. The stable adsorption sites and binding energies of a Ni atom on three intrinsic defects were calculated and compared to those on perfect side walls. All defects enhance Ni adsorption, and the single vacancy shows the most exothermic binding. These results shed light on the nature of the interaction of the transition metal with defects in SWNT, an important topic to the many aspects of carbon nanotubes interacting with transition metals. Particularly, this is useful for the fabrication of nanosized transition metal particles supported on carbon nanotubes.  相似文献   
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110.
A new electrochemical DNA detection method using double-stranded probes and competitive hybridization reaction offers highly selective discrimination of single base mismatch without post-hybridization washing.  相似文献   
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