HYDROGENATION OF CO_2 OVER ULTRAFINECuO-ZnO-SiO_2 CATALYST-REACTION CONDITIONS AND MECHANISM

IntroductionAsoncofthemostabundantandcheapestcarbonsourccs,Co2u,ithsteadilyincreasingconcentrationintheatmospherenotonlyleadstothelossofcarbonsource,butalsocausesgrccnhouseeffects.Recently,Co2wastestedasafecdstockformcthanolproductionovcrdiffcrentcatalystsclse.'hcrell'21,butmostofthesecatalystswerebasedonthecombinationofcoppcrandzincandpreparedbycoprecipitation,ioncxchangcor'l3'4]Accordingtoextensivestudiesaboutsupports,SiO2wasoncoftheimpregnationl3'4]Accordingtoextensivestudiesaboutsupport…     

热脱附谱表征SmNtn03表面氧的吸附态

从SmMnO,的清洁表面上吸附Oz后的热脱附谱图中发现，气相氧不仅在SmMnO,表面吸附，而且也大量进入由于高温(820K)抽空而造成的晶格氧缺陷中.实验结果表明，O:在SmMnO，的表面吸附存在着两种化学吸附态，且均为二级吸附，即O}以离解方式吸附在SmMnOa的表面，同时对氧的热脱附谱采用脱附速率等温线法处理，结果得到这两种化学吸附态的平均脱附活化能分别为67. 0和93. 9k1 /mol，其中脱附活化能较大的那一种吸附态仅在较高温度下吸附时才出现，因而该吸附态应具有较大的吸附活化能.     

Properties of Optical Phase-Locked Loop Based on Four Wave Mixing in Semiconductor Laser Amplifiers

In this paper, the properties of the optical phase-locked loop(PLL) based on the four-wave mixing in the semiconductor laser amplifiers (SLAs) are discussed. The components that achieve the function of detecting the bit phase of the input optical signal are concerned and discussed in detail together as a function module named as the optical bit phase detector referred to the general electronic PLL. Therefore, most of the properties of the optical PLL can be analyzed by applying the general phase-locked theory. Here the stability of the optical PLL is discussed. It's shown that the variance of input signal power in the practical application will cause optical PLL system unstable because of its long loop delay. The influence on the output phase jitter of the optical PLL is also investigated.     

Graphene-supported anatase TiO2 nanosheets for fast lithium storage

We have designed a unique hybrid structure by directly growing ultrathin anatase TiO(2) nanosheets onto graphene support for fast lithium storage. With exposed (001) high-energy facets, these TiO(2) nanosheets serve as ideal hosts for fast and efficient lithium storage. On the other hand, the graphene support serves as a highly conductive substrate that is beneficial to the high-rate performance.     

Ellipsoidal hollow nanostructures assembled from anatase TiO2 nanosheets as a magnetically separable photocatalyst

A simple approach was proposed to synthesize three types of ellipsoidal hollow nanostructures whose shells are assembled from anatase TiO(2) nanosheets (NSs) with exposed (001) facets. Among them, ellipsoid Fe(3)O(4)@TiO(2)-NS nanorattles can be readily generated as a magnetically separable photocatalyst with enhanced activity through in situ reduction of the α-Fe(2)O(3) core.     

The influence of triplet energy levels of bridging ligands on energy transfer processes in Ir(III)/Eu(III) dyads

A series of N^N,O^O-bridging ligands based on substituted 1-(pyridin-2-yl)-3-methyl-5-pyrazolone and their corresponding heteroleptic iridium(III) complexes as well as Ir-Eu bimetallic complexes were synthesized and fully characterized. The influence of the triplet energy levels of the bridging ligands on the energy transfer (ET) process from the Ir(III) complexes to Eu(III) ions in solution was investigated at 77 K in Ir(III)/Eu(III) dyads. Photophysical experiment results show the bridging ligands play an important role in the ET process. Only when the triplet energy level of the bridging ligand was lower than the triplet metal-to-ligand charge transfer ((3)MLCT) energy level of the Ir moiety, was pure emission from the Eu(III) ion observed, implying complete ET took place from the Ir moiety to the Eu(III) ion.     

Formation of SnO2 hollow nanospheres inside mesoporous silica nanoreactors

We report an interesting approach for efficient synthesis of SnO(2) hollow spheres inside mesoporous silica "nanoreactors". The as-prepared products are shown to have a uniform size distribution and good structural stability. When evaluated for their lithium storage properties, these SnO(2) hollow spheres manifest improved capacity retention.     

Effects of additives on the morphology of solution phase aggregates formed by active layer components of high-efficiency organic solar cells

Processing additives are used in organic photovoltaic systems to optimize the active layer film morphology. However, the actual mechanism is not well understood. Using X-ray scattering techniques, we analyze the effects of an additive diiodooctane (DIO) on the aggregation of a high-efficiency donor polymer PTB7 and an acceptor molecule PC(71)BM under solar cell processing conditions. We conclude that DIO selectively dissolves PC(71)BM aggregates, allowing their intercalation into PTB7 domains, thereby optimizing both the domain size and the PTB7-PC(71)BM interface.