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81.
Siamak Shoravi Gustaf D. Olsson Bj?rn C. G. Karlsson Ian A. Nicholls 《International journal of molecular sciences》2014,15(6):10622-10634
Aspects of the molecular-level basis for the function of ethylene glycol dimethacrylate and trimethylolproprane trimethacrylate crosslinked methacrylic acid copolymers molecularly imprinted with (S)-propranolol have been studied using a series of all-component and all-atom molecular dynamics studies of the corresponding prepolymerization systems. The crosslinking agents were observed to contribute to template complexation, and the results were contrasted with previously reported template-recognition behavior of the corresponding polymers. Differences in the extent to which the two crosslinkers interacted with the functional monomer were identified, and correlations were made to polymer-ligand recognition behavior and the results of nuclear magnetic resonance spectroscopic studies studies. This study demonstrates the importance of considering the functional monomer–crosslinker interaction when designing molecularly imprinted polymers, and highlights the often neglected general contribution of crosslinker to determining the nature of molecularly imprinted polymer-template selectivity. 相似文献
82.
In a Combined Heat and Power (CHP) network, it is sometimes optimal to install a device for storing heat from one period of time to another. Several possibilities exist. If the electricity demand is high, while at the same time the district heating load is too small to take care of the heat from the CHP plant, it could be optimal to store heat from peak periods and discharge the storage under off-peak. It might also be optimal to store heat during off-peak and use it under the district heating peak load. The storage is then used for decreasing either the district heating demand or for decreasing the electricity load used for space heating. The paper shows how a mixed integer program is developed for use in the optimization process. As a case study, the CHP system of Malmö, Sweden, is used. Further, a sensitivity analysis is elaborated in order to show how the optimal solution will vary due to changes in certain input data. 相似文献
83.
A method to estimate the annual collected energy and the annual average optical efficiency factor is suggested. The radiation distribution on the absorber of an asymmetric CPC collector with a flat bi-facial absorber is measured for three different absorber mounting angles using a photo diode. The annual optical efficiency factors and a relative measure of the annual collected energy are determined for collectors with the absorber fin thickness 0.5 and 1 mm, and for a collector with a teflon convection suppression film mounted around the absorber. With the local optical efficiency factors and the annual incident solar energy distribution considered, the analysis indicates that the energy gain for a mounting angle of 20° is higher than for a collector with 65° absorber mounting angle. The annual collected energy is increased with 6–8% if the absorber fin thickness is increased from 0.5 to 1 mm. The annual average optical efficiency factor is relatively independent of the absorber mounting angle. It was found to be 0.87–0.88 for a collector with a 0.5 mm thick absorber fin and 0.92 for a collector with a 1 mm thick absorber fin or for a collector with 0.5 mm thick absorber fin with a teflon convection suppression film added. The low annual average optical efficiency factor is not caused by the uneven irradiance distribution but by the relatively high UL-values. 相似文献
84.
85.
Yolanda HedbergOskar Karlsson Peter SzakalosInger Odnevall Wallinder 《Materials Letters》2011,65(14):2089-2092
Electron Backscatter Diffraction (EBSD) studies clearly revealed a different crystallographic structure of the smallest particle size fraction of gas-atomized AISI 316 L stainless steel powder (< 4 μm) compared with larger sized fractions of the same powder (< 45 μm). Despite similar chemical compositions, the predominating structure of the smallest particle size fraction was ferritic (i.e., has ferromagnetic properties) whereas the larger sized particle fractions and massive 316 L revealed an expected austenitic and non-magnetic structure. From these findings, it follows that direct magnetic separation can be applied to separate very fine sized particles. These structural differences explain previously observed dissimilarities from corrosion and metal release perspectives. 相似文献
86.
Oskar Rexfelt Lars Almefelt Daniel Zackrisson Teres Hallman Johan Malmqvist MariAnne Karlsson 《Research in Engineering Design》2011,22(3):153-171
This paper outlines the results of a project aiming to develop and apply methods for service co-creation with customers, focusing
on the early phases of service development. The project is collaboration between a manufacturing firm in the automotive industry,
one of their B2B-customers (a transportation firm), as well as a university, all in Sweden. The research team selected and
developed methods and work practices for problem analysis, idea generation, development and evaluation of services. Thus doing,
methodological influence was taken from the area of engineering design. The proposed approaches were applied in a service
development experiment mainly based on workshops. The experiment was followed up by an analysis of the resulting output, an
interview series, and an evaluation by peers in focus groups. The goal of this article is to answer the following research
questions: (1) What is the industrial applicability of co-creating services using a structured approach, e.g. what are the
benefits and challenges? (2) What do the different actors contribute with using this approach, and what possible factors influence
the nature and quality of the actors’ contributions? (3) Based on the answers to the questions above, what aspects should
be considered to support situated planning and execution of future service co-creation projects? A central conclusion is that
a structured approach is industrially applicable, but it is also evident that there is no completely universal recipe for
service innovation. Addressing these insights, the paper also contributes with guidelines to support the situation-adapted
set-up of future service co-creation projects. 相似文献
87.
Doubts have been raised on whether the car industry will manage to reach the goal set by the Voluntary Agreement with the
European Commission, unless tougher measures are taken to reduce CO2 emissions. Taking a stance from the concept of downsizing, we study the historical development of two strategies: first,
shifting the market toward smaller cars, market downsizing; second, a technical downsizing, i.e., technical improvements that
have enabled a reduction of engine size. We focus on the Swedish new car market from 1975 to 2002. Analysis is done by combining
sales statistics with databases over car model parameters. The development of the top and bottom 10% and 20% of the car market
of various parameters points to an increased differentiation of the market; still, the market share of small models remains
low. We identify the potential for downsizing created by increase of maximum specific torque and power and conclude that these
have enabled the cylinder volume to stabilize around 2 l. Increase in engine size has also partly been dampened by the utilization
of supercharging. The potential savings of fuel use presented by the introduction of a sixth gear in manual gearboxes have
not materialized since gearshifts have not systematically been used to lower engine speed. We conclude that there are few
signs of a downsizing in the Swedish new car fleet. From a market perspective, larger cars are still dominant and the technical
potentials to reduce engine size have not been harnessed.
相似文献
Frances SpreiEmail: |
88.
J Kartus S Stener R Nilsén U Nilsson BI Eriksson J Karlsson 《Canadian Metallurgical Quarterly》1998,8(6):449-455
Dairy calves under 14 days of age with naturally occurring, uncomplicated diarrhea were treated for 3 days with a hypertonic oral electrolyte solution with (n = 15) or without (n = 12) psyllium. Clinical response and clinical pathology data were compared between the 2 groups. Glucose absorption was evaluated on days 1 and 3 by measurement of plasma glucose and lactate and serum insulin concentrations for 4 hours after formula administration. On day 1, glucose, lactate, and insulin concentrations were lower in psyllium-fed calves than in control calves, with significant differences noted in glucose and lactate concentrations at several time points (P < 0.05). Plasma lactate concentrations were higher at several times in both treatment groups on day 3 than on day 1 (P < 0.05). Fecal consistency was markedly different in psyllium-fed calves as compared with control calves within 24 hours of psyllium supplementation. Fecal percent dry matter content was lower in psyllium-fed calves than in control calves at least once a day during supplementation and on day 3 compared with day 0 in the psyllium-fed calves (P < 0.05). There were no significant differences in clinical performance scores, hydration status, arterial blood gas, serum anion gap, electrolyte, or total CO2 concentrations. Addition of psyllium to an oral electrolyte solution resulted in immediate alterations in glucose absorption without impairing rehydration in diarrheic calves, but differences were transient and did not affect clinical outcome. 相似文献
89.
T Jensen EM Aliouat B Lundgren OP Settnes A Karlsson C Dahlgren E Dei-Cas N Obel 《Canadian Metallurgical Quarterly》1998,45(5):544-547
The production of free radicals in human neutrophils was studied in both Pneumocystis carinii derived from cultures of L2 rat lung epithelial-like cells and Pneumocystis carinii purified from human lung. Using the cytochrome C technique, which selectively measured extracellular superoxide generation, hardly any free radical production was observed after stimulation with cultured rat-derived P. carinii. A chemiluminescence technique, which separately measured intra- and extracellular free radical production, was subsequently employed to differentiate the free radical generation. It was established that 1) P. carinii stimulated intra- but not extracellular free radical production in human neutrophils, 2) opsonized cultured rat-derived P. carinii stimulated human neutrophils to a strong intracellular response of superoxide production, and 3) opsonized P. carinii, purified from human lung also stimulated human neutrophils to produce intracellular free radicals. 相似文献
90.