We report experiments using fluorene and terthiophene copolymer as the active layer in bilayer devices with C60. The highest short circuit current, open circuit voltage and power conversion efficiency upon AM1.5 illumination were 6.8 mA/cm2, 0.68 V and 2.33%, respectively. Density functional theory analysis was used to identify the most stable configurations of the terthiophene moieties in the polymer: the most stable form has the thiophene rings in the alternate configuration (anti) and the second conformation has the thiophene rings pointing to the same direction (syn). Comparing theoretical results with measurements of absorbance, X-ray diffraction, and X-ray reflectometry experiments, we conclude that the annealing treatment produces conformational anti to syn transition along the backbone of poly[9,9′-n-dihexyl-2,7-fluorene-alt-2,5-terthiophene] (LaPPS45). The syn segments of the chain condensed then in a lamellar ordered structure which increases the degree of crystallinity of the annealed samples and improve the light harvest at long wavelengths. From absorption measurements of films submitted to different annealing temperatures and with the help of theoretical calculations we propose a “wave-like” aggregation pattern to the syn segments in those lamellas. 相似文献
In this paper, the problem of single and multiple degree elevation and reduction for DP curves and surfaces is considered and expressed in matrix representations. Using monomial matrix representations of the univariate DP polynomials, single and multiple degree elevation matrices can be derived by minor extension of this monomial matrix. Given this result, matrices of constrained single and multiple degree reduction can be readily obtained. Finally, important and sufficient conditions for degree reduction can also be found from these resulting matrices. 相似文献
Buildings in private and domestic use are responsible for about 30% of the global greenhouse gas emissions attributable mainly to their need for heating and cooling energy. This corresponds to about 40% of the global final energy consumption. Therefore, a viable implementation of building energy efficiency policies is inevitable to realize a transformation of the energy system to mitigate climate change. Within the building sector lies a huge potential for emission reduction consisting in the renovation of the existing building stock and climate-friendly building guidelines applicable to new constructions, both adapting CO2-neutral technology solutions. However, as there are several different pathways leading to a decarbonized energy system, there is always the question which political and technological solutions are most efficient, effective, and feasible. This paper aims to analyze building efficiency policy measures and instruments and the related technological solutions in two front-runner countries of the energy transition, possessing different structural conditions: Germany and Norway. We hence apply a comparative approach which allows us to present and assess the policies in place. The paper answers three research questions: (1) Which policies prevail in Germany and Norway to foster the deployment of energy efficient and decarbonized solutions for residential buildings? (2) How do these policies respond to country-specific barriers to the energy transition in the building sector, and (3) What effects do they have on the actual implementation of technological and societal solutions? This research provides a new insight to the highly relevant topic of energy efficiency in buildings in the context of international Intended Nationally Determined Contribution benchmarking and discusses some unsolved trade-offs in the translation of the global climate governance into the national building sector. 相似文献
Progressive fetal infection/inflammation is strongly associated with neural injury after preterm birth. We aimed to test the hypotheses that progressively developing fetal inflammation leads to neuroinflammation and impaired white matter development and that the histopathological changes can be detected using high-field diffusion tensor magnetic resonance imaging (MRI). Chronically instrumented preterm fetal sheep at 0.7 of gestation were randomly assigned to receive intravenous saline (control; n = 6) or a progressive infusion of lipopolysaccharide (LPS, 200 ng intravenous over 24 h then doubled every 24 h for 5 days to induce fetal inflammation, n = 7). Sheep were killed 10 days after starting the infusions, for histology and high-field diffusion tensor MRI. Progressive LPS infusion was associated with increased circulating interleukin (IL)-6 concentrations and moderate increases in carotid artery perfusion and the frequency of electroencephalogram (EEG) activity (p < 0.05 vs. control). In the periventricular white matter, fractional anisotropy (FA) was increased, and orientation dispersion index (ODI) was reduced (p < 0.05 vs. control for both). Histologically, in the same brain region, LPS infusion increased microglial activation and astrocyte numbers and reduced the total number of oligodendrocytes with no change in myelination or numbers of immature/mature oligodendrocytes. Numbers of astrocytes in the periventricular white matter were correlated with increased FA and reduced ODI signal intensities. Astrocyte coherence was associated with increased FA. Moderate astrogliosis, but not loss of total oligodendrocytes, after progressive fetal inflammation can be detected with high-field diffusion tensor MRI. 相似文献
We demonstrate in this communication that stable high internal phase emulsions consisting of a majority dispersed cement slurry as aqueous phase and a continuous but minority monomer oil phase can be produced. Polymerisation of the monomer phase using both a conventional thermal method as well as by fast setting using carbon fibres as resistance heaters results in bicontinuous polymer cement hybrid materials. We found that a reduction of the polymerisation time from 24 h to 90 min did not affect the physical characteristics, such as density and porosity, of the polymer-cement hybrids but results in a decrease of the crush strength and a significantly reduced elastic modulus. 相似文献
This article appraises the career of architect Ralph Erskine focusing on the context for his contribution to Swedish and British social housing and planning. Erskine's formative experience during the 1930s and his subsequent transnational career are utilized to explore the mutual influences of planning ideals across national boundaries. The Garden City ideal, Functionalism and the urban village concept are considered for their long-term contribution to his work. In addition, vernacular architecture and participatory planning are explored as influences on the evolution of his community architecture vision by the 1970s. Drawing on evidence from urban developments in Britain and Sweden, the discussion demonstrates that Erskine's cultural transfer of international planning ideals essentialized aspects of British and Swedish historical culture. The article concludes with a discussion of the 1970s and Erskine's role in the redevelopment of Byker in Newcastle upon Tyne. This process was hailed as a pioneer moment in the English community architecture movement. However, this study demonstrates that Erskine should be distinguished from the grassroots activism of the community architecture movement. Rather the discussion emphasizes that his participatory planning was underpinned by a structural tension between social engineering and democratic participation that was generated and reinforced by his transnational career. 相似文献
This paper establishes a connection between structure sensitive categorial inference and classical modal logic. The embedding theorems for non-associative Lambek Calculus and the whole class of its weak Sahlqvist extensions demonstrate that various resource sensitive regimes can be modelled within the framework of unimodal temporal logic. On the semantic side, this requires decomposition of the ternary accessibility relation to provide its correlation with standard binary Kripke frames and models. 相似文献
Polyamidoamines were synthesized by Michael-type polyaddition reaction and conjugates characterized by 1H NMR, 31Mosmann, T.Rapid Colorimetric Assay for Cellular Growth and Survival: Application to Proliferation and Cytotoxicity Assays. J. Immunol. Meth. 1983, 65, 55–63.[Crossref], [PubMed], [Web of Science ®], [Google Scholar]P NMR, FTIR, SEM, and EDX. The biological evaluation of the new materials revealed 12–30% inhibition of the human breast cancer cells (MCF7) and 25% of the Plasmodium falciparum malaria parasites by the conjugates. The hemolysis assay revealed that these materials did not have any effect on the host red blood cell membrane. The release mechanism of neridronate followed Korsmeyer–Peppas model at pH 1.2 with a diffusion coefficient of 0.45 indicating a Fickian diffusion mechanism; Higuchi model at pH 6.0 thus indicating a diffusion mechanism. 相似文献
Detection of enzyme biomarkers originating from either bio-fluids or contaminating microorganisms is of utmost importance in clinical diagnostics and food safety. Herein, we present a simple, low-cost and easy-to-use sensing approach based on the switchable peroxidase-mimicking activity of plasmonic gold nanoparticles (AuNPs) that can catalyse for the oxidation of 3,3’,5’5-tetramethylbenzidine (TMB) for the determination of protease enzyme. The AuNP surface is modified with casein, showing dual functionalities. The first function of the coating molecule is to suppress the intrinsic peroxidase-mimicking activity of AuNPs by up to 77.1%, due to surface shielding effects. Secondly, casein also functions as recognition sites for the enzyme biomarker. In the presence of protease, the enzyme binds to and catalyses the degradation of the coating layer on the AuNP surface, resulting in the recovery of peroxidase-mimicking activity. This is shown visually in the development of a blue colored product (oxidised TMB) or spectroscopically as an increase in absorbance at 370 and 650 nm. This mechanism allows for the detection of protease at 44 ng·mL−1 in 90 min. The nanosensor circumvents issues associated with current methods of detection in terms of ease of use, compatibility with point-of-care testing, low-cost production and short analysis time. The sensing approach has also been applied for the detection of protease spiked in ultra-heat treated (UHT) milk and synthetic human urine samples at a limit of detection of 490 and 176 ng·mL−1, respectively, showing great potential in clinical diagnostics, food safety and quality control.