无机敏化对金红石光吸收特性的影响

用过渡金属氧化物对金红石单晶作无机敏化处理，用 ＵＶ－ＶＩＳ， ＸＦＡ， ＸＲＤ和 ＬＲＳ等测试方法分析敏化前后的金红石单晶，研究无机敏化对金红石单晶光吸收特性的Ｘ卜向结果表明， Ｃｒ，Ｍｎ氧化物的敏化使金红石的本征吸收边红移， Ｃｏ； Ｆｅ， Ｖ氧化物的敏化使吸收边的尾部抬高 Ｃｒ离子与基质晶体形成了固溶体 Ｃｒ２ＴｉＯ５是吸收边红移的原因， Ｃｒ２ＴｉＯ５在可见波段有光吸收。

D-A-π-A型有机敏化染料的光谱调控与稳定性提升

有机功能染料在新型光电子领域具有重要的应用前景,染料的光学特性与稳定性是影响其应用价值的重要因素。应用于有机太阳电池的敏化染料是决定电池器件光电转换效率和长期稳定性的关键组分。传统有机敏化染料的设计主要遵循电子给体-共轭桥连-电子受体(D-π-A)模型,但其对设计宽光谱、高效率、高稳定性的有机敏化染料存在明显的局限性。近年来系统引入额外的强吸电子基团作为电荷分离'阱'受体,成功发展高稳定性敏化染料,显著提升敏化染料稳定性及光电转换效率,创新地提出D-A-π-A型纯有机敏化染料概念。本文主要依据在纯有机敏化染料设计与合成方面的相关工作,简单介绍D-A-π-A模型中额外受体对染料能级、光谱等性能的调控机制,以及该模型对提升有机敏化染料稳定性方面的作用及原理。

从“神魂相搏”中医理论探讨药物成瘾的动机敏化机制

药物成瘾动机敏化理论的核心内容为强迫用药、觅药行为的发生。中医认为气血亏虚、心神失养、肝魂失摄是成瘾性发生的关键,"神魂相搏"理论很好地阐释了强迫用药和觅药行为的发生机制。

高柔土建结构振动主动控制的研究进展

阐述了高耸柔性结构振动主动控制的必要性、基本概念及其关键技术，综述了其研究现状及存在的问题，并指出高耸柔性结构机敏化／智能化是确保结构安全性与耐久性的重要途径。

中医七情之“思”与成瘾心理渴求的辩证关系

渴求及继发觅药行为是精神依赖的主要表现,为复吸的动机力量。动机敏化理论的提出为成瘾复吸提供了较为合理的解释,为成瘾的神经生物学机制研究提供了理论基础。本文从文献复习角度探讨了中医七情之"思"与成瘾心理渴求之间存在的辩证关系。

Study on Mechanization Hybrid Rice Seed Production Technology and Combine Breeding Advances

[Objectives]Current hybrid rice seed production mechanization and a new kind of hybrid rice seed production mechanization using Bentazone sensitive lethal genes for mechanized seed production technology are introduced in this paper.[Method]Sensitive Restorer Bentazone lethal dose of filtering,parental and seed weight are bred combinations of several aspects of the system described,and presented mechanized seed technology new research directions.[Results]The method of using Bentazone sensitive lethal genes for mechanized seed production technology is feasible,economic,seed production and combination advantages.[Conclusions] Using Bentazone sensitive lethal genes for mechanized seed production technology is the new study direction of mechanic production.

Mechanized Seed Production of Xinhunyou No.6 through Mixed Seeding of Parents' Seeds

Hybrid rice Xinhunyou No. 6 could be cultivated by mixing male and fe- male parents and performing seedling raising followed by transplanting, mechanical planting or mechanical direct seeding according to the production methods of com- mercial rice. During flowering stage, leaf cutting, application of ＂920＂ and pollination were conducted; after pollination, bentazon with a certain concentration was sprayed to kill the male parent; and the hybrid rice was harvested mechanically. Before storage, color separation was performed to remove little remaining male parent, thereby achieving whole-process mechanization of hybrid rice seed production. This study introduced mechanized seed production of Xinhunyou No. 6 through mixed- seeding from the aspects including mechanical direct seeding, seeding raising fol- lowed by transplanting and mechanical planting.

Photovoltaic Performance of Triphenylamine Dyes-sensitized Solar Cells Employing Cobalt Redox Shuttle and Influence of π-conjugated Spacers

Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells （DSSCs）. The DSSCs incorporating tris（1,10-phenanthroline）eobalt（Ⅱ/Ⅲ）-based redox elec- trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the w-conjugated spacers of organic dyes upon the photovoltage and photocur- rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination.

Doping [Ru(bpy)3]^(2+ )into metal-organic framework to facilitate the separation and reuse of noble-metal photosensitizer during CO2 photoreduction

It is desirable to develop highly efficient and sustainable catalytic systems for CO_(2) photoreduction using efficient heterogeneous photosensitizers(PSs);however,this remains a great challenge.In this study,we doped[Ru(bpy)3]^(2+) into UiO-metal-organic frameworks(MOFs)to facilitate the separation and reuse of noble metal PS.By simply adjusting the loading amount,a series of heterogeneous photoactive MOFs,namely,UiO-Ru-1,UiO-Ru-2,and UiO-Ru-3,were constructed to act as heterogeneous PSs to drive the efficient CO_(2) photoreduction under visible-light irradiation.Remarkably,UiO-Ru-2 exhibited the best photosensitizing ability among the prepared MOFs in sensitizing the iron quarterpyridine catalyst(C-l),and the CO yield reached as high as 171 mmol/g with ca.100%selectivity,which is a record value among all the MOF-based photocatalysts.This photoactive MOF can be recycled and reused three times without any obvious activity loss,signifying its good photochemical stability.Experimental investigations confirmed that the strong visible absorption,long-lived excited state,appropriate redox potential,good photocatalytic stability,and excellent collaboration with C-l were attributable to the superior catalytic activity.This work highlights an avenue for constructing heterogeneous PSs with excellent recyclability using MOF as the platform for efficient CO_(2) reduction.

Photogenerated carrier transfer mechanism and photocatalysis properties of TiO_2 sensitized by Zn(Ⅱ) phthalocyanine

The Zn(Ⅱ) phthalocyanine sensitized TiO2(ZnPc-TiO2) nanoparticles were prepared by hydrothermal method via impregnation with ZnPc.The as-prepared photocatalysts were characterized by X-ray diffractometry(XRD) and diffuse reflectance spectroscopy(DRS),and the surface photovoltage spectroscopy(SPS) and photocatalytic degradation of rhodamine B(RhB) were studied under illuminating.The experimental results indicate that TiO2 sensitized by ZnPc extends its absorption band into the visible region effectively,and the sensitized TiO2 has higher activity than TiO2(Degussa P-25) under the simulated solar light and the visible light.Based on the DRS and SPS results,the mechanism about the photogenerated carrier transfer between TiO2 and ZnPc is proposed.At a lower ZnPc content(≤0.20 μmol/g),ZnPc monomer acts as the electron donor,which provides the photoinduced electrons to the conduction band of TiO2.These photoinduced electrons can transfer to molecular oxygen(O2),leading to the formation of active species,such as superoxide/hydroxide radicals and singlet oxygen,which is beneficial to the photocatalytic reaction.While at a higher ZnPc content(>0.20 μmol/g),the formation of ZnPc dimer results in the decrease of photocatalytic activities of ZnPc-TiO2 photocatalyst.

A Reduced Mechanism for Flame Inhibition by Phosphorus-containing Compounds Based on Level of Importance Analysis

A reduced mechanism for propane/air combustion and its flame inhibition by phosphorus-containing compounds (PCCs) is constructed with the level of importance (LOI) method. The analysis is performed on solutions of freely propagating premixed flames with detailed chemical kinetics involving 121 species and 682 reactions proposed by Jayaweera et al. For the non-homogeneous reaction-diffusion system, the chemical lifetime of each species is weighted by its diffusion timescale, and the characteristic flame timescale is used to normalize the chemical lifetime. The definition of sensitivity in LOI is extended so that multi-parameters can be used as sensitivity targets. Propane, oxygen, dimethyl methylphosphonate (DMMP), and flame speed are selected to be perturbed for sensitivity analysis, the species with low LOI index are removed, and reactions involving the redundant species are excluded from the mechanism. A skeletal mechanism is obtained, which consists of 57 species and 268 elementary reactions. Calculations for laminar flame speeds, key flame radicals and catalytic cycles using the skeletal mechanism are in good agreement with those by using the detailed mechanism over a wide range of equivalence ratio undoped and doped with DMMP.

Explicit diagnosis of the local ozone production rate and the ozone-NOx-VOC sensitivities

In the troposphere, ozone is a harmful gas compound to both human health and vegetation. Ozone is produced from the reaction of NO_x(@NO + NO_2) and VOCs(volatile organic compounds) with light. Due to the highly nonlinear relationships between ozone and its precursors, proper ozone mitigation relies on the knowledge of chemical mechanisms. In this study, an observation-based method is used to simulate ozone formation and elucidate its controlling factors for a rural site on the North China Plain. The instantaneous ozone production rate is calculated utilizing a box model using the dataset obtained from the Wangdu campaign. First, the model was operated in a time-dependent mode to calculate the ozone production rate at each time stamp. The calculated ozone formation rate showed a diurnal average maximum value of 17 ppbv/h(1-h diurnal averaged). The contribution of individual peroxy radicals to ozone production was analyzed. In addition, the functional dependence of calculated P(O_3) reveals that ozone production was in a NO_x-limited regime during the campaign. Furthermore, the missing peroxy radical source will further extend NO_x-limited conditions to earlier in the day, making NO_xlimitation dominate more of a day than the current chemical model predicts. Finally, a multiple scenarios mode,also known as EKMA(empirical kinetic modeling approach), was used to simulate the response of P(O_3) to the imaginary change in precursor concentrations. We found that ozone production was in the NO_x-limited region. However, the use of NO_2 measured by the molybdenum converter and/or the absence of a peroxy radical source in the current chemical model could over-emphasize the VOC-limited effect on ozone production.

Plasma density evolution in plasma opening switch obtained by a time-resolved sensitive He-Ne interferometer

To understand the formation process of vacuum gap in coaxial microsecond conduction time plasma opening switch(POS),we have made measurements of the line-integrated plasma density during switch operation using a time-resolved sensitive He-Ne interferometer.The conduction current and conduction time in experiments are about 120 kA and 1 s,respectively.As a result,more than 85%of conduction current has been transferred to an inductive load with rise time of 130 ns.The radial dependence of the density is measured by changing the radial location of the line-of-sight for shots with the same nominal POS parameters.During the conduction phase,the line-integrated plasma density in POS increases at all radial locations over the gun-only case by further ionization of material injected from the guns.The current conduction is observed to cause a radial redistribution of the switch plasma.A vacuum gap forms rapidly in the plasma at 5.5 mm from the center conductor,which is consistent with the location where magnetic pressure is the largest,allowing current to be transferred from the POS to the load.