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101.
Vladimir S. Koroliuk Raimondo Manca Guglielmo D’Amico 《Journal of Mathematical Sciences》2014,196(5):644-651
The storage impulsive processes given by a sum of random variables on a superposition of two renewal processes are considered on increasing time intervals. The averaging, diffusion approximation, and large deviation problem are studied in the series scheme with a small parameter series under suitable scaling. 相似文献
102.
Vladimir Martis Martin Martis John Lipp Dirk Detollenaere Trevor Rayment Gopinathan Sankar Wim Bras 《Journal of synchrotron radiation》2014,21(4):744-750
Energy‐resolved electron‐yield X‐ray absorption spectroscopy is a promising technique for probing the near‐surface structure of nanomaterials because of its ability to discriminate between the near‐surface and bulk of materials. So far, the technique has only been used in model systems. Here, the local structural characterization of nanoporous cobalt‐substituted aluminophosphates is reported and it is shown that the technique can be employed for the study of open‐framework catalytically active systems. Evidence that the cobalt ions on the surface of the crystals react differently to those in the bulk is found. 相似文献
103.
Vladimir Dolgovskiy Stéphane Schilt Nikola Bucalovic Gianni Di Domenico Serge Grop Benoît Dubois Vincent Giordano Thomas Südmeyer 《Applied physics. B, Lasers and optics》2014,116(3):593-601
We demonstrate the first ultra-stable microwave generation based on a 1.5-μm diode-pumped solid-state laser (DPSSL) frequency comb. Our system relies on optical-to-microwave frequency division from a planar-waveguide external cavity laser referenced to an ultra-stable Fabry–Perot cavity. The evaluation of the microwave signal at ~10 GHz uses the transportable ultra-low-instability signal source ULISS®, which employs a cryo-cooled sapphire oscillator. With the DPSSL comb, we measured ?125 dBc/Hz phase noise at 1 kHz offset frequency, likely limited by the photo-detection shot-noise or by the noise floor of the reference cryo-cooled sapphire oscillator. For comparison, we also generated low-noise microwave using a commercial Er:fiber comb stabilized in similar conditions and observed >20 dB lower phase noise in the microwave generated from the DPSSL comb. Our results confirm the high potential of the DPSSL technology for low-noise comb applications. 相似文献
104.
Alexey V. Salin Albert R. Fatkhutdinov Anton V. Il'in Vladimir I. Galkin 《国际化学动力学杂志》2014,46(4):206-215
Quaternization of triphenylphosphine with maleic and cis‐aconitic acids is strongly accelerated by participation of the cis‐carboxyl group in stabilization of the phosphonium zwitterion intermediate by intramolecular hydrogen bonding, in spite of steric hindrance by the acid's reaction center. A similar effect for trans‐isomeric acids is not observed, which can be rationalized on the basis of spatial structures of the generated zwitterions, implying an electrostatic interaction between the phosphonium center and carbonyl oxygen atom. The effect of anchimeric assistance decreases when the intramolecular hydrogen bonding disfavors attack of the phosphine on the sterically less hindered carbon atom of the C=C bond, as observed for cis‐aconitic acid. 相似文献
105.
106.
Huijuan Yang Hui Wang Shan Ji Yanjiao Ma Vladimir Linkov Rongfang Wang 《Journal of Solid State Electrochemistry》2014,18(6):1503-1512
Development of suitable supports has been proven as an important preparation process for high active catalysts of fuel cell. In this work, a carbon material was prepared by pyrolyzing cocoons with ferric chloride as activator, and then Pt nanoparticles (ca. 50 wt.%) were deposited on its surface. The characteristics of X-ray diffraction and transmission electron microscopy showed that the face-centered cubic structured Pt nanoparticles with nano-sized crystals interconnected each other via grain boundaries were formed on the surface of pyrolyzed cocoons. Afterwards, electrochemical results demonstrate that the nanostructured Pt supported on this support exhibits higher catalytic activity and CO tolerance than Pt nanoparticles supported on Vulcan carbon for methanol oxidation reaction. 相似文献
107.
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109.
Matveev Vladimir B. Semenov-Tian-Shansky Michel 《Letters in Mathematical Physics》2019,109(6):1269-1270
Letters in Mathematical Physics - 相似文献
110.
Design of pincer complexes based on (methylsulfanyl)acetic/propionic acid amides with ancillary S‐ and N‐donors as potential catalysts and cytotoxic agents 下载免费PDF全文
Svetlana G. Churusova Diana V. Aleksanyan Andrei A. Vasil'ev Ekaterina Yu. Rybalkina Olga Yu. Susova Zinaida S. Klemenkova Rinat R. Aysin Yulia V. Nelyubina Vladimir A. Kozlov 《应用有机金属化学》2018,32(6)
Pincer complexes featuring readily tunable tridentate ligand frameworks comprise one of the most actively studied classes of organometallic and metal–organic compounds and find extensive use in catalysis, organic synthesis, materials science, and other fields of chemistry and allied disciplines. Currently growing attention is devoted to non‐classical ligand scaffolds, such as functionalized carboxamides, which offer multiple options for directed structural modifications. In this study, the reactions of (methylsulfanyl)acetyl and propanoyl chlorides with 2‐(aminomethyl)pyridine, 2‐(2‐aminoethyl)pyridine, 8‐aminoquinoline and 2‐(diphenylthiophosphoryl)aniline afford a series of new pincer‐type ligands based on functionalized carboxamides. The ligands obtained readily undergo direct cyclopalladation under the action of PdCl2(NCPh)2 in dichloromethane at room temperature, resulting in Pd(II) pincer complexes with N,N,S‐ and S,N,S‐donor sets. Importantly, some of the cyclopalladated derivatives can also be produced efficiently under solvent‐free conditions according to the approach recently developed by our group. The complexes obtained have been tested for cytotoxicity against several human cancer cell lines and catalytic activity in the model Suzuki reaction. The results have been compared to those for the related Pd(II) pincer complexes to define the main structure–activity relationships and to outline the most promising structures for further investigations. 相似文献