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1.
The addition of metallic Ir and Pt to a fullerene-forming, atmospheric-pressure plasma reactor was found to influence the generation of carbonaceous products. It was observed that the added metals were efficiently dispersed into the plasma and that their presence increased the yield of fullerenes. The addition of Ir led to a noticeable shift in the fullerene distribution towards C60, whereas the addition of Pt increased the proportion of C60 oxides and decreased the proportion of higher fullerenes. Addition of Ir also caused a reduction of the soot particle size and the formation of a considerable quantity of carbon nanotubes.  相似文献   
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A novel methanol-tolerant oxygen-reduction catalyst, Iridium-selenium (Ir-Se) chalcogenide, was synthesized by chemical precipitation in an organic solvent. Auger electron spectroscopy (AES) analysis confirmed that the synthesized Ir-Se chalcogenide had a chemical formula of Ir4Se. This chalcogenide showed strong catalytic activity towards the oxygen reduction reaction (ORR) and a high methanol tolerance. It was found that most of the oxygen could be directly reduced to water through a four-electron pathway with less than 10% hydrogen peroxide (H2O2) being produced during the ORR. The improvement in catalytic activity of the Ir-Se chalcogenide in comparison with that of pure Ir might be attributed to the effect of a bimetallic interaction.  相似文献   
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建立了吐温80─N_2O_2体系测定痕量铱的新的化学发光分析法,方法的检测限为3.0×10 ̄(-9)g/ml;线性范围为1.0×1O ̄(-8)~1.0×10 ̄(-5)g/ml;测定100ppb铱溶液的相对标准偏差为6.5%。  相似文献   
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The preparation and characterization of a new cyclometalated iridium complex with 2-(1-naphthalene) pyridine ligand were reported. An electrophosphorescent device was fabricated by using this new iridium complex as guest and poly-(cyano-paraphenylene) as host. Red electrophosphorescence was observed with an emission peak at approximately 600 nm. An external quantum efficiency of 1.3% was achieved in this electrophosphorescent polymer light-emitting devices.  相似文献   
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Polymer-based blue electrophosphorescent light-emitting diodes are reported by doping iridium(III) diazine complex (DFPPM)2Ir(pic) (DFPPM = 2-(2,4-difluorophenyl)-pyrimidine, pic = picolinate) in poly(vinylcarbazole) (PVK) as the source of emission. The iridium(III) diazine complex shows sky blue emission with its maximum emission peak at 476 nm originating from an admixture of triplet metal-to-ligand charge-transfer and ligand-centered states. The (DFPPM)2Ir(pic)-doped device furnishes a maximum external quantum efficiency of 2.2% and power efficiency of 1.9 lm/W at a 10 wt% doping concentration.  相似文献   
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Single-crystalline iridium dioxide nanowires show the time-dependent universal conductance fluctuations (TUCFs) at cryogenic temperatures. The conductance fluctuations persist up to temperature T as high as nearly 10 K. The root-mean-square TUCF magnitudes increase with decreasing T, reaching approximately 0.1 e2 / h at 1.7 K. We ascribe these conductance fluctuations to originating from the conduction electrons scattering upon mobile defects (moving scattering centers). Our measured TUCF characteristics are satisfactorily explained in terms of the existing TUCF theory in its three-dimensional form. The extracted electron dephasing length Lφ(1.7 K) ≃90 nm is smaller than the diameter (≈ 180 nm) of our nanowires.  相似文献   
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Hydrogen gas generation with an effective response to changing application demands was achieved with the use of a hydrogen storage battery based on aqueous cesium bicarbonate hydrogenation/formate dehydrogenation, homogeneously catalyzed by an Ir(I)N-heterocyclic carbene complex. In this device, the storage solution was circulated through a small volume tubular reactor heated to the required high temperature to allow fast hydrogen evolution while the high volume reservoir was kept at ambient temperature at which no H2 was generated. Merely by the control of the reactor temperature, it was possible to regulate the rate of hydrogen evolution as required. The results also demonstrate the feasibility of homogeneous catalysis for the purpose of hydrogen generation in flow systems.  相似文献   
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