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111.
Delissen Arnoud van Keulen Fred Langelaar Matthijs 《Structural and Multidisciplinary Optimization》2020,61(6):2557-2575
Structural and Multidisciplinary Optimization - In many engineering applications, the dynamic frequency response of systems is of high importance. In this paper, we focus on limiting the extreme... 相似文献
112.
Anton Matthijs Berghuis Alexei Halpin Quynh Le‐Van Mohammad Ramezani Shaojun Wang Shunsuke Murai Jaime Gmez Rivas 《Advanced functional materials》2019,29(36)
An enhanced delayed fluorescence is demonstrated experimentally in tetracene single crystals strongly coupled to optical modes in open cavities formed by arrays of plasmonic nanoparticles. Hybridization of singlet excitons with collective plasmonic resonances in the arrays leads to the splitting of the material dispersion into a lower and an upper polariton band. This splitting significantly modifies the dynamics of the photoexcited tetracene crystal, resulting in an increase of the delayed fluorescence by a factor of 4. The enhanced delayed fluorescence is attributed to the emergence of an additional radiative decay channel, where the lower polariton band harvests long‐lived triplet states. There is also an increase in total emission, which is wavelength dependent, and can be explained by the direct emission from the lower polariton band, the more efficient light out‐coupling, and the enhancement of the excitation intensity. The observed enhanced fluorescence opens the possibility of efficient radiative triplet harvesting in open optical cavities, to improve the performance of organic light emitting diodes. 相似文献
113.
Upali S. Amarasinghe Jacobus Vijverberg Wasantha S. Weliange Matthijs Vos 《Lakes & Reservoirs: Research and Management》2014,19(1):56-69
The food webs for three Sri Lankan reservoirs, Minneriya (ancient and shallow), Udawalawe (young and shallow) and Victoria (young and deep), were compared. The species richness of the fish communities was highest in Minneriya (30 species), intermediate in Udawalawe (21 species) and lowest in Victoria (18 species). The fish species belonged to 11 families, with Cyprinidae dominating the community in terms of both abundance and species richness. The daily quantity of food consumed per fish species was used to distinguish weak from strong trophic interactions in these food webs. The fish community consumption pattern was characterized by a few strong interactions and many weak ones. The number of major consumers (i.e. contributing >5% of the total fish community consumption) for each reservoir was small and similar for all three reservoirs. Dawkinsia singhala and Amblypharyngodon melettinus were the two major consumers in all three reservoir food webs. Puntius chola was a major consumer in Minneriya and Victoria, although not in Udawalawe, where it fed less on detritus than for the other two food webs. The fish community fed mainly at the bottom of the food web, primarily on algae, macrophytes and detritus in all three reservoirs, with very little piscivory occurring. The average food‐web length was measured as the mean trophic index weighted for the consumption rates of the various fish populations that together comprised the fish community. The average food‐web length in these three Sri Lankan reservoirs relatively short, compared with most other tropical lake/reservoir food webs in Asia and Africa for which relevant data were available. Furthermore, traditionally unexploited species (Oreochromis mossambicus; O. niloticus), in contrast to species of commercial fisheries interest, are major role players in the trophic dynamics of reservoir ecosystems. Thus, based on this study, the potential of their exploitation should be considered in the management of reservoir fisheries. 相似文献
114.
Chris E. Finlayson Richard H. Friend Matthijs B. J. Otten Erik Schwartz Jeroen J. L. M. Cornelissen Roeland J. M. Nolte Alan E. Rowan Paolo Samorì Vicenzo Palermo Andrea Liscio Kalina Peneva Klaus Müllen Sara Trapani David Beljonne 《Advanced functional materials》2008,18(24):3947-3955
The electronic transport properties of stacks of perylene‐bis(dicarboximide) (PDI) chromophores, covalently fixed to the side arms of rigid, helical polyisocyanopeptides, are studied using thin‐film transistors. In device architectures where the transistor channel lengths are somewhat greater than the average polymer chain length, carrier mobilities of order 10?3 cm2 V?1 s?1 at 350 K are found, which are limited by inter‐chain transport processes. The influence of π–π interactions on the material properties is studied by using PDIs with and without bulky substituents in the bay area. In order to attain a deeper understanding of both the electronic and the electronic‐transport properties of these systems, studies of self‐assembly on surfaces are combined with electronic characterization using Kelvin probe force microscopy, and also a theoretical study of electronic coupling. The use of a rigid polymer backbone as a scaffold to achieve a full control over the position and orientation of functional groups is of general applicability and interest in the design of building blocks for technologically important functional materials, as well as in more fundamental studies of chromophoric interactions. 相似文献
115.
Tom J. Savenije Martien J. W. Vermeulen Matthijs P. de Haas John M. Warman 《Solar Energy Materials & Solar Cells》2000,61(1)
We have used the flash-photolysis time-resolved microwave conductivity technique (TRMC) to monitor charge separation between a smooth film of anatase TiO2 (ca 80 nm) and spin-coated layers of a dialkoxyphenylene-vinylene polymer (20–140 nm thick) on nanosecond flash-photolysis in the polymer absorption band at 544 nm. The quantum efficiency of electron injection into the TiO2 from photons absorbed in the polymer layer can be calculated by comparing the conductivity resulting from 544 nm irradiation with that from direct band gap excitation of the anatase layer at 308 nm. The maximum efficiency per incident photon, is ca 6% for thicknesses in the range of 30–50 nm of the polymer layer. Charge separation persists well into the microsecond region. 相似文献
116.
117.
Vincenzo Palermo Erik Schwartz Chris E. Finlayson Andrea Liscio Matthijs B. J. Otten Sara Trapani Klaus Müllen David Beljonne Richard H. Friend Roeland J. M. Nolte Alan E. Rowan Paolo Samorì 《Advanced materials (Deerfield Beach, Fla.)》2010,22(8):E81-E88
The optimization of the electronic properties of molecular materials based on optically or electrically active organic building blocks requires a fine‐tuning of their self‐assembly properties at surfaces. Such a fine‐tuning can be obtained on a scale up to 10 nm by mastering principles of supramolecular chemistry, i.e., by using suitably designed molecules interacting via pre‐programmed noncovalent forces. The control and fine‐tuning on a greater length scale is more difficult and challenging. This Research News highlights recent results we obtained on a new class of macromolecules that possess a very rigid backbone and side chains that point away from this backbone. Each side chain contains an organic semiconducting moiety, whose position and electronic interaction with neighboring moieties are dictated by the central macromolecular scaffold. A combined experimental and theoretical approach has made it possible to unravel the physical and chemical properties of this system across multiple length scales. The (opto)electronic properties of the new functional architectures have been explored by constructing prototypes of field‐effect transistors and solar cells, thereby providing direct insight into the relationship between architecture and function. 相似文献
118.
Matthijs J. Koornstra 《Sadhana》2007,32(4):365-395
The macroscopic trend of road traffic fatalities in any motorized country is described and predicted by the product of rather
well fitting functions of time for the exponential decay of fatality risk per unit of traffic volume and the S-shaped Gompertz
function of traffic volume growth. This product defines a single-peaked development of road traffic deaths, where its peak
reaches earlier the sooner and faster a nation or region motorizes massively. Since in developing countries long series of
traffic volume data are absent, another model for the fit and prediction of road traffic fatalities for developing countries
is used, based on the relationships of income level per capita with road traffic mortality. Also this model implies that at
some point in time road traffic deaths will start declining for ever, also worldwide. After empirically derived corrections
for missing or incomplete data and police under-reporting, it is estimated that 1·2 million deaths and almost 8 million serious
injuries are caused by road traffic worldwide in 2000. Using realistic income level predictions the new income-dependent model
predicts markedly later and higher fatality peaks than the verified time-dependent model. It might be assumed that the developing
countries could learn faster to increase their road safety by knowledge transfer from developed countries. Four prediction
scenarios are specified for modified income-dependent models of road traffic death and serious injury developments up to 2050.
Depending on the scenario the world total of road fatalities begins to reduce soon or only after 2035 with a global peak of
about 1·8 million road traffic deaths, where the national fatality reduction starts later the lower the national income per
capita is. Without the potentially achievable learning scenario the road fatality reductions in developed countries may not
be enough to compensate the road fatality increases in developing countries, while road fatality increases may even occur
after 2060 in countries with the lowest levels of income per capita. 相似文献
119.
Matthijs W. Leeuw 《Propellants, Explosives, Pyrotechnics》1990,15(3):92-96
In this paper a novel method to determine the reliability of a bridgewire fuze head is proposed. It is assumed that a bridgewire will respond positively to a current pulse if the bridgewire temperature exceeds a critical value as a result of the pulse. To calculate the bridgewire temperature the distributions of four thermal parameters that characterize the electrothermal response of a bridgewire fuze head are used. Preliminary results indicate that this novel approach is in agreement with classical methods. Furthermore, one needs to test a limited amount of items and only a fraction of the tested items is destroyed. 相似文献
120.
Poting Liu Alexander Schleusener Gabriel Zieger Arne Bochmann Matthijs A. van Spronsen Vladimir Sivakov 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2206318
Tin-containing layers with different degrees of oxidation are uniformly distributed along the length of silicon nanowires formed by a top-down method by applying metalorganic chemical vapor deposition. The electronic and atomic structure of the obtained layers is investigated by applying nondestructive surface-sensitive X-ray absorption near edge spectroscopy using synchrotron radiation. The results demonstrated, for the first time, a distribution effect of the tin-containing phases in the nanostructured silicon matrix compared to the results obtained for planar structures at the same deposition temperatures. The amount and distribution of tin-containing phases can be effectively varied and controlled by adjusting the geometric parameters (pore diameter and length) of the initial matrix of nanostructured silicon. Due to the occurrence of intense interactions between precursor molecules and decomposition by-products in the nanocapillary, as a consequence of random thermal motion of molecules in the nanocapillary, which leads to additional kinetic energy and formation of reducing agents, resulting in effective reduction of tin-based compounds to a metallic tin state for molecules with the highest penetration depth in the nanostructured silicon matrix. This effect will enable clear control of the phase distributions of functional materials in 3D matrices for a wide range of applications. 相似文献