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81.
Matias Sevel Rasmussen Tor Justesen Anders Dohn Jesper Larsen 《European Journal of Operational Research》2012
In the Home Care Crew Scheduling Problem a staff of home carers has to be assigned a number of visits to patients’ homes, such that the overall service level is maximised. The problem is a generalisation of the vehicle routing problem with time windows. Required travel time between visits and time windows of the visits must be respected. The challenge when assigning visits to home carers lies in the existence of soft preference constraints and in temporal dependencies between the start times of visits. 相似文献
82.
Manson JL Baldwin AG Scott BL Bendix J Del Sesto RE Goddard PA Kohama Y Tran HE Ghannadzadeh S Singleton J Lancaster T Möller JS Blundell SJ Pratt FL Zapf VS Kang J Lee C Whangbo MH Baines C 《Inorganic chemistry》2012,51(14):7520-7528
[Ni(HF(2))(3-Clpy)(4)]BF(4) (py = pyridine) is a simple one-dimensional (1D) coordination polymer composed of compressed NiN(4)F(2) octahedra that form chains with bridging HF(2)(-) ligands. In spite of significant distortion of the HF(2)(-) bridge, a quasi-1D antiferromagnetic (AFM) behavior was observed with J(FHF) = 4.86 K. 相似文献
83.
Dr. Chenguang Lou Josephine Tuborg Boesen Dr. Niels Johan Christensen Dr. Kasper K. Sørensen Prof. Peter W. Thulstrup Dr. Martin Nors Pedersen Prof. Ernest Giralt Prof. Knud J. Jensen Prof. Jesper Wengel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(25):5676-5684
DNA nanostructures have been designed and used in many different applications. However, the use of nucleic acid scaffolds to promote the self-assembly of artificial protein mimics is only starting to emerge. Herein five coiled-coil peptide structures were templated by the hybridization of a d -DNA triplex or its mirror-image counterpart, an l -DNA triplex. The self-assembly of the desired trimeric structures in solution was confirmed by gel electrophoresis and small-angle X-ray scattering, and the stabilizing synergy between the two domains was found to be chirality-independent but orientation-dependent. This is the first example of using a nucleic acid scaffold of l -DNA to template the formation of artificial protein mimics. The results may advance the emerging POC-based nanotechnology field by adding two extra dimensions, that is, chirality and polarity, to provide innovative molecular tools for rational design and bottom-up construction of artificial protein mimics, programmable materials and responsive nanodevices. 相似文献
84.
Møller Jesper Christensen Heidi S. Cuevas-Pacheco Francisco Christoffersen Andreas D. 《Methodology and Computing in Applied Probability》2021,23(2):569-591
Methodology and Computing in Applied Probability - This paper concerns space-sphere point processes, that is, point processes on the product space of $\mathbb {R}^{d}$ (the d-dimensional Euclidean... 相似文献
85.
Jesper Lægsgaard Peter J. Roberts Morten Bache 《Optical and Quantum Electronics》2007,39(12-13):995-1008
Photonic crystal fibers (PCFs) have had a substantial impact on nonlinear fiber optics and shortpulsed fiber laser systems due to their novel dispersion properties. The large normal or anomalous waveguide dispersion available in such fibers opens up a number of new opportunities not accessible with standard fiber technology. In this contribution, the fundamentals of PCF dispersion are briefly reviewed along with earlier results. In addition, some of our recent work on dispersion tailoring to facilitate nonlinear processes, and dispersion control in lasers will be presented. 相似文献
86.
Jesper Makholm Byskov 《Operations Research Letters》2004,32(6):547-556
We give tight upper bounds on the number of maximal independent sets of size k (and at least k and at most k) in graphs with n vertices. As an application of the proof, we construct improved algorithms for graph colouring and computing the chromatic number of a graph. 相似文献
87.
Dual‐Function Cobalt–Nickel Nanoparticles Tailored for High‐Temperature Induction‐Heated Steam Methane Reforming 下载免费PDF全文
Morten G. Vinum Mads R. Almind Dr. Jakob S. Engbæk Dr. Søren B. Vendelbo Dr. Mikkel F. Hansen Prof. Dr. Cathrine Frandsen Prof. Dr. Jesper Bendix Dr. Peter M. Mortensen 《Angewandte Chemie (International ed. in English)》2018,57(33):10569-10573
The tailored chemical synthesis of binary and ternary alloy nanoparticles with a uniform elemental composition is presented. Their dual use as magnetic susceptors for induction heating and catalytic agent for steam reforming of methane to produce hydrogen at temperatures near and above 800 °C is demonstrated. The heating and catalytic performance of two chemically synthesized samples of CoNi and Cu ? CoNi are compared and held against a traditional Ni‐based reforming catalyst. The structural, magnetic, and catalytic properties of the samples were characterized by X‐ray diffraction, elemental analysis, magnetometry, and reactivity measurements. For induction‐heated catalysts, the conversion rate of methane is limited by chemical reactivity, as opposed to the case of traditional externally heated reformers where heat transport limitations are the limiting factor. Catalyst production by the synthetic route allows controlled doping with miniscule concentrations of auxiliary metals. 相似文献
88.
The feasibility of using the affinity CE methodologies pre-equilibrium CZE and CE frontal analysis was tested on interaction systems exhibiting rapid on-and-off kinetics. Experimentally, the methodologies differ only with respect to the volume of sample introduced into the capillary. Pre-equilibrium CZE has been considered amendable to interactions with slow on-and-off kinetics only; however, it has recently been applied in studies of interactions with fast on-and-off kinetics. The effect of varying the sample volume introduced hydrodynamically into the capillary on the apparent degree of complexation was studied. For two different binding systems, the fraction of free analyte was found to be overestimated using pre-equilibrium CZE as compared to volumes providing plateau peak conditions as used with frontal analysis. Results indicate that frontal analysis conditions lead to more robust binding assays and thus more reliable data. The validity of data obtained by pre-equilibrium CZE may be low, thus the use of an experimental setup providing plateau peaks is highly recommended. It is suggested that the effect of altering the sample volume on the degree of binding should be investigated as part of method development and validation. 相似文献
89.
Microemulsion electrokinetic chromatography (MEEKC) was assessed as a tool for determination of octanol-water partition coefficients using 34 solutes encompassing 8 carbonate esters. It was confirmed that microemulsions containing 1.44-2.88% w/w SDS, 6.49% w/w 1-butanol, and 0.82% w/w n-heptane constitute a good model of octanol-water partitioning in the pH range of 1.4-7.4. Use of the migration index concept led to improved repeatability of the MEEKC method compared to the use of retention factors. Using a dynamical coating, a high electroosmotic flow at pH 1.4 and 4.75 was achieved expanding the practical pH working range of the MEEKC system. The correlation obtained between the migration index and log P was unaffected by pH indicating that the properties of the microemulsion droplets and, thus, partitioning are independent of pH. No evidence for congeneric behavior was found for the sample set comprising solutes with different hydrogen bonding properties suggesting that simple reference compounds can be used as calibrators. Lipophilicity estimates for the series of carbonate esters were obtained. The increase in lipophilicity with chain length was smaller than expected from the Hansch substituent constant, pi. 相似文献
90.
Jurriaan M Zwier Albert M Brouwer Tamás Keszthelyi Gurusamy Balakrishnan Jesper F Offersgaard Robert Wilbrandt Frédérique Barbosa Urs Buser Jér?me Amaudrut Georg Gescheidt Stephen F Nelsen Charles D Little 《Journal of the American Chemical Society》2002,124(1):159-167
The radical cation of 1,3,6,8-tetraazatricyclo [4.4.1.1(3,8)]dodecane (TTD) has been studied using magnetic resonance and optical spectroscopic methods and computational techniques. With the help of deuterated isotopomers, assignments of EPR and resonance Raman spectra could be unequivocally established. The results demonstrate that the radical cation has D(2d) symmetry, and instantaneous electron delocalization over the four equivalent nitrogen atoms occurs. This extensive delocalization in a completely saturated system is a unique feature of the TTD radical cation. The spectroscopy of TTD, in contrast to that of simpler diamines such as 1,4-diaza[2.2.2]bicyclooctane, simultaneously reveals the consequences of orbital interactions through space and through bonds. The relationship between nitrogen pyramidalization and hyperfine coupling constants in nitrogen-centered radical cations with a number of different bonding arrangements is reviewed. 相似文献