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91.
Magdolna Háda Veronika Nagy Anikó Takátsy József Deli Jan Hait Attila Agócs 《Tetrahedron letters》2012,53(19):2480-2482
We describe the synthesis of carotenoid derivatives via the azide–alkyne click reaction and optimize the conditions for these sensitive molecules. After finding the mildest conditions possible for the reaction we were able to use the click reaction for the synthesis of PEG–carotenoid conjugates starting from carotenoid pentynoates and PEG azides. 相似文献
92.
Conor T. Riley Tien A. Kieu Joseph S. T. Smalley Si Hui Athena Pan Sung Joo Kim Kirk W. Post Alireza Kargar Dimitri N. Basov Xiaoqing Pan Yeshaiahu Fainman Deli Wang Donald J. Sirbuly 《固体物理学:研究快报》2014,8(11):948-952
Currently there is a strong interest in plasmonic materials operating in the near‐infrared (NIR), however, conventional metals such as gold and silver possess high optical losses in this region. In this work we demonstrate localized surface plasmon resonances (LSPRs) with low loss in the NIR region by utilizing atomic layer deposition to deposit thin films of aluminium doped zinc oxide onto silicon nanopillars created via nanopshere lithography. The deposited films have excellent conformality and the LSPRs can be tuned from the mid‐infrared to the NIR by controlling the doping concentration, deposition temperature and nanostructure morphology. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
93.
The authors introduce the definition of block-wise m-dependent with respect to somepositive real sequence for random variables taking values in a separable Banach space,prove some general results on the strong convergence of blockwise m-dependent randomvariables,and in particular,give positive answers to Móricz conjectures([5])by asharper theorem. 相似文献
94.
规模收益分析的DEA方法 总被引:3,自引:0,他引:3
文章利用规模收益的几何意义得到不同规模收益的判别条件,并进一步由技术有效DEA模型的最优值来分析边界点的规模收益。 相似文献
95.
Wang D Lu S Kulesza PJ Li CM De Marco R Jiang SP 《Physical chemistry chemical physics : PCCP》2011,13(10):4400-4410
Both Keggin-type phosphotungstic acid (HPW) and Pd are not prominent catalysts towards the oxygen reduction (ORR), but their composite Pd-HPW catalyst produces a significantly higher electrochemical activity for the ORR in acidic media. The novel composite catalyst was synthesized by self-assembly of HPW on multi-walled carbon nanotubes (MWCNTs) via the electrostatic attraction between negatively charged HPW and positively charged poly(diallyldimethylammonium (PDDA)-wrapped MWCNTs, followed by dispersion of Pd nanoparticles onto the HPW-PDDA-MWCNT assembly. The as-prepared catalyst was characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). TEM images show that Pd nanoparticles were uniformly dispersed on the surface of MWCNTs even when the Pd loading was increased to 60 wt%. Electrochemical activity of the catalysts for the ORR was evaluated by steady state polarization measurements using a rotating disk electrode. Compared with the acid treated MWCNTs, Pd nanoparticles supported on the HPW-assembled MWCNTs show a much higher ORR activity that is comparable to conventional Pt/C catalysts. The high electrocatalytic activities could be related to high dispersion of Pd nanoparticles as well as synergistic effects originating from the high proton conductivity of HPW. The Pd/HPW-PDDA-MWCNTs system as the cathode catalyst in proton exchange membrane fuel cells is demonstrated. 相似文献
96.
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98.
Deli Xiao Pierre Dramou Hua He Lien Ai Pham-Huy Hui Li Yuyang Yao Chuong Pham-Huy 《Journal of nanoparticle research》2012,14(7):1-12
A poly(vinyl chloride) (PVC) main chain was grafted with poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) containing a quaternary amine group using atom transfer radical polymerization. The successful synthesis of a PVC-g-PDMAEMA graft copolymer was confirmed by Fourier transform infrared, nuclear magnetic resonance, thermogravimetric analysis, and transmission electron microscopy. The PVC-g-PDMAEMA graft copolymer was used as a structure-directing agent (SDA) for the fabrication of a mesoporous thin film containing a titanium dioxide (TiO2) layer. To control the porosity of the resultant inorganic layer, the ratio of SDA to TTIP as well as the concentration of the sol?Cgel was varied. The structure and porosity of the mesoporous film were characterized by XRD and SEM analysis. The mesoporous TiO2 film fabricated on the FTO surface was used as a photoanode for the dye-sensitized solar cell (DSSC). DSSC performance was the greatest when using TiO2 film with a higher porosity and lower interfacial resistance. The highest energy conversion efficiency reached 3.2?% at 100?mW/cm2, which was one of the highest reported values for a quasi-solid-state DSSC with 600-nm-thick TiO2 film. 相似文献
99.
Fossi Jules Tagne Deli Vandi Njitacke Zeric Tabekoueng Mendimi Joseph Marie Kemwoue Florent Feudjio Atangana Jacques 《Nonlinear dynamics》2022,109(2):925-942
Nonlinear Dynamics - The memristor is a nonlinear electronic nanodevice with incredible biomimetic characteristics generally used by neurologists, more specifically in neuromorphics, to design... 相似文献
100.
有顾客需求变动的车辆调度干扰管理研究 总被引:4,自引:0,他引:4
为解决来自顾客需求变动所引发的物流配送干扰问题,提出基于干扰管理思想构建扰动恢复策略与方案.应用虚拟单车场实现了车辆调度扰动恢复问题转化,提出了车辆调度扰动恢复策略以及扰动度量方法,以作为车辆调度干扰管理建模的基础;对有顾客需求变动的车辆调度干扰管理问题,分析了顾客需求变动造成的扰动并进行了辨识;建立了相应的干扰管理模型,并提出了归一化处理办法对VRPTW问题进行有效兼容;结合干扰管理模型的特点,改进了基于顾客的编码表示方法;根据干扰管理思想,设计了遗传算法对干扰管理模型进行了求解.最后通过实验验证了模型与算法的有效性. 相似文献