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1.
The performance of five hole-transporting layers (HTLs) is investigated in both single-junction perovskite and Cu(In, Ga)Se2 (CIGSe)-perovskite tandem solar cells: nickel oxide (NiOx,), copper-doped nickel oxide (NiOx:Cu), NiOx+SAM, NiOx:Cu+SAM, and SAM, where SAM is the [2-(3,-6Dimethoxy-9H-carbazol-9yl)ethyl]phosphonic acid (MeO-2PACz) self-assembled monolayer. The performance of the devices is correlated to the charge-carrier dynamics at the HTL/perovskite interface and the limiting factors of these HTLs are analyzed by performing time-resolved and absolute photoluminescence ((Tr)PL), transient surface photovoltage (tr-SPV), and X-ray/UV photoemission spectroscopy (XPS/UPS) measurements on indium tin oxide (ITO)/HTL/perovskite and CIGSe/HTL/perovskite stacks. A high quasi-Fermi level splitting to open-circuit (QFLS-Voc) deficit is detected for the NiOx-based devices, attributed to electron trapping and poor hole extraction at the NiOx-perovskite interface and a low carrier effective lifetime in the bulk of the perovskite. Simultaneously, doping the NiOx with 2% Cu and passivating its surface with MeO-2PACz suppresses the electron trapping, enhances the holes extraction, reduces the non-radiative interfacial recombination, and improves the band alignment. Due to this superior interfacial charge-carrier dynamics, NiOx:Cu+SAM is found to be the most suitable HTL for the monolithic CIGSe-perovskite tandem devices, enabling a power-conversion efficiency (PCE) of 23.4%, Voc of 1.72V, and a fill factor (FF) of 71%, while the remaining four HTLs suffer from prominent Voc and FF losses.  相似文献   
2.
The effect of layer thickness disorder in periodic multilayers on x-ray reflectivity is investigated numerically and experimentally. We present ensemble calculations, taking into account absorption and interfacial roughness. It is demonstrated that layer thickness disorder yields band broadening and increased integrated reflectivity For applications we concentrate on extrema of the ensembles, giving the highest integrated reflectivity We develop global optimization methods that can also be used to generate specified reflection band structures. In a few examples, applications of the optimization methods are discussed. To illustrate the practical applicability of the methods, we compare experimental realizations to the calculation. In one case we achieve a 42% increase in integrated reflectivity in the 130 ? < λ < 190 ? spectral range with respect to a periodic multilayer with its first-order Bragg peak in the center of that range. Accurate control of layer thicknesses is our main experimental obstacle.  相似文献   
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To increase understanding of the etiology and epidemiology of nicotine dependence among adolescent smokers, the present study examined the occurrence and development of distinct nicotine dependence symptom profiles in a sample of adolescent smokers. A total of 25 secondary schools throughout the Netherlands participated in a 1-year longitudinal study. Multiple dimensions of nicotine dependence were assessed, at two time points, among 641 adolescents (aged 14–17 years) who were classified as smokers. Results showed 4 distinct, yet stable, nicotine dependence subtypes that could be characterized by quantitative as well as qualitative differences. The symptom profiles were similar for males and females but differentially associated with previously identified correlates of nicotine dependence, namely parental smoking, peer smoking, and depressive mood. Finally, differential links of the 4 subtypes were found with regard to smoking uptake and cessation. The finding of qualitative different subgroups of adolescent smokers may have important implications for intervention efforts regarding nicotine dependence and smoking cessation. Such efforts may need to be tailored to the specific subgroups’ needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
This study examined whether detrimental childhood relationships with parents were related to partner relationship quality and emotional adjustment in adulthood. The authors tested a theoretical model in which (a) low-quality parent-child relationships were related to conflict and low-quality communication with parents in adolescence, (b) parent-adolescent conflict and low-quality communication were linked to low-quality partner relationships in young adulthood, and (c) low-quality partner relationships in young adulthood were predictive of low-quality partner relationships as well as depression, anxiety, and dissatisfaction with life at midlife. Multi-informant data were used from 212 Swedish individuals who were followed from birth into adulthood. Results demonstrated that, as hypothesized, negative parent-child bonds were indirectly related to low-quality partner relationships and dissatisfaction with life in adulthood (but not anxiety and depression) through conflictual parent-adolescent communication and low-quality partner relationships in young adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The dynamic Monte Carlo method has been used to simulate the 2 A + B2 → 2 AB reaction catalyzed by a reconstructing substrate. Oscillatory behavior and spatio-temporal is studied as a function of grid size. Spatio-temporal pattern formation has been simulated in various forms: cellular patterns, target patterns, rotating spirals, and turbulent patterns. Cellular patterns are a manifestation of a local synchronization mechanism in which all reaction fronts periodically extinguish each other. This illustrates that dynamic Monte Carlo simulations form a promising technique and can be used to predict macroscopic kinetic phenomena on a molecular basis.  相似文献   
7.
The combined use of quantum chemistry and spectroscopy to provide a basis of microkinetics modelling is discussed.  相似文献   
8.
Prospects of plasma medicine: Applications of Tissue Tolerable Plasmas (TTP) Based on the current knowledge on the physical properties and biological effects of tissue tolerable plasma (ttp) potential perspectives of plasma medicine are discussed. Currently, the foundations for the following medical applications of ttp are developed by an interdisciplinary research team: Prevention and/or treatment of diseases such as chronic wounds, skin and mucosal infectious diseases, localized tumors, promotion of angiogenesis, and tissue ablation Inhibition and/or elimination of biofilms by prevention of biofilm development due to surface treatment and/or plasma steered application of antimicrobial active layers with drug delivery function on foreign objects implanted into humans (implantable prosthesis, contact lenses, stents etc.) as well as elimination of biofilms by direct action of ttp on surfaces and tissues (chronic wounds, tooth surface, prosthesis) promotion of the incorporation of implants into viable tissue by changing the surface of materials (hydrophobicity) Promotion of penetration of topically applied drugs with therapeutic results Assessment of veterinary indications Improved cleaning performance in reprocessing of medical devices by surface modification.  相似文献   
9.
Recent research has shown that daily changes in self-efficacy predict lapses and relapse into smoking after quitting among adolescent daily smokers, but it is not known if and how momentary self-efficacy is associated with affect-motivational states and external contexts. In the present study, 134 adolescent daily smokers were monitored daily during 1 week prior to and 3 weeks after they began their quit attempt. Participants completed questions on smoking, self-efficacy, affect-motivational states (craving and negative affect), and external contexts (seeing others smoke, experiencing a stressful event, and alcohol and coffee consumption) three times a day. Affect-motivational states as well as all external contexts (except for coffee consumption) were associated with lower self-efficacy when participants were still abstinent, but also after they had lapsed. Associations between the situational contexts and self-efficacy did not largely depend on individual characteristics such as baseline self-efficacy and age. Among girls, however, the negative associations between self-efficacy and negative affect and drinking alcohol were found to be stronger. These results show that adolescents' self-efficacy during a quit attempt may be responsive to affect-motivational states and external contexts, both before and after lapsing. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
正家具最早出现在人类生活中时,是作为提高生活效率的"器具"使用的,它具备基础的功能性,外型和整体架构都十分简单。随着人类社会的不断演变,家具的存在早已被附上一层又一层的定义,设计师们的想象力通过家具的外型得以展现;而它的内部结构,成为展示制造工艺的最好平台;它的质感与视觉效果,通过材料的异同展现出不一样的姿态。荷兰设计师Oato所设计的Stuck Chair映射了工  相似文献   
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