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81.
Stefan Thiemann Swetlana J. Sachnov Fredrik Pettersson Roger Bollström Ronald Österbacka Peter Wasserscheid Jana Zaumseil 《Advanced functional materials》2014,24(5):625-634
A new class of biofriendly ionogels produced by gelation of microcellulose thin films with tailored 1‐ethyl‐3‐methylimidazolium methylphosphonate ionic liquids are demonstrated. The cellulose ionogels show promising properties for application in flexible electronics, such as transparency, flexibility, transferability, and high specific capacitances of 5 to 15 μF cm?2. They can be laminated onto any substrate such as multilayer‐coated paper and act as high capacitance dielectrics for inorganic (spray‐coated ZnO and colloidal ZnO nanorods) and organic (poly[3‐hexylthiophene], P3HT) electrolyte‐gated field‐effect transistors (FETs), that operate at very low voltages (<2 V). Field‐effect mobilities in ionogel‐gated spray‐coated ZnO FETs reach 75 cm2 V?1 s?1 and a typical increase of mobility with decreasing specific capacitance of the ionogel is observed. Solution‐processed, colloidal ZnO nanorods and laminated cellulose ionogels enable the fabrication of the first electrolyte‐gated, flexible circuits on paper, which operate at bending radii down to 1.1 mm. 相似文献
82.
Conley DJ Humborg C Rahm L Savchuk OP Wulff F 《Environmental science & technology》2002,36(24):5315-5320
Deep-water oxygen concentrations in the Baltic Sea are influenced by eutrophication, but also by saltwater inflows from the North Sea. In the last two decades, only two major inflows have been recorded and the lack of major inflows is believed to have resulted in a long-term stagnation of the deepest bottom water. Analyzing data from 1970 to 2000 at the basin scale, we show that the estimated volume of water with oxygen, <2 mL L(-1), was actually at a minimum at the end of the longest so-called stagnation period on record. We also show that annual changes in dissolved inorganic phosphate water pools were positively correlated to the area of bottom covered by hypoxic water, but not to changes in total phosphorus load, thus addressing the legacy of eutrophication on a basinwide scale. The variations in phosphorus pools that have occurred during the past decades do not reflect any human action to reduce inputs. The long residence time and internally controlled variation of the large P pool in the Baltic Sea has important implications for management of both N and P inputs into this eutrophicated enclosed basin. 相似文献
83.
84.
A methodology is proposed for glitch-free power switching of unused circuit blocks in leakage dominated deep-submicrometre technologies. With respect to conventional non-glitch-free approaches, significantly faster settling time and lower power consumption during the activation of the block are obtained. 相似文献
85.
Erik Abenius Ulf Andersson Fredrik Edelvik Lasse Eriksson Gunnar Ledfelt 《International journal for numerical methods in engineering》2002,53(9):2185-2199
We present a new approach to time domain hybrid schemes for the Maxwell equations. By combining the classical FD‐TD scheme with two unstructured solvers, one explicit finite volume solver and one implicit finite element solver, we achieve a very efficient and flexible second‐order scheme. The second‐order accuracy of the hybrid scheme is verified through convergence studies on perfectly conducting as well as dielectric and diamagnetic circular cylinders. The numerical results also show its superiority to the FD‐TD scheme. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
86.
R Erttmann T Tafese F Berthold R Kerbl J Mann L Parker F Schilling P Ambros H Christiansen M Favrot H Kabisch B Hero T Philip 《Canadian Metallurgical Quarterly》1998,34(9):1391-1397
Between January 1986 and May 1996, 870,313 children were tested in European neuroblastoma (NB) screening programmes. Among these children, 82 cases of NB (age range 4-24 months, median 11 months) were detected by screening. 83% of the patients had localised NB and 17% were diagnosed with generalised NB (stage 4, 10%; stage 4s, 7%). Unfavourable biological markers (MYCN amplification, loss of heterozygosity (LOH) 1p36, DNA di/tetraploidy) were observed in 14% of 76 biologically examined cases. The median follow-up time of all the patients was 21.5 months (range 1-101 months). To date, 69 patients are in complete remission (CR) and 2 patients have died due to therapy (stage 4, 1 patient; stage 3, 1 patient with unfavourable markers). Apart from screened patients, 16 other patients with NB were found who had previously had a normal screening test, i.e. 'false negative' patients (age range 10-41 months, median 31.5 months). The median interval between screening and diagnosis was 24.5 months (range 6-35 months). 11 of the 'false negative' patients suffered from generalised NB (stage 4) and 5 had localised NB at diagnosis. Unfavourable biological markers were observed in 7/12 patients. 5 patients have died, 2 achieved partial remission and 9 CR. 9 of the 11 patients with unfavourable biological markers diagnosed due to NB screening are currently in CR. It is very likely that, among the patients without unfavourable biological markers, we detected tumours which may have regressed spontaneously. These children may have undergone 'unnecessary,' but unavoidable, diagnostic procedures and therapy. To reduce the number of 'false negative' patients, a later screening could be helpful and should be evaluated. 相似文献
87.
In this paper a fully IC-compatible silicon wafer-to-wafer fusion-bonding process is described. Before the bonding, the silicon surfaces are treated by chemicals which do not attack the electronic circuits or aluminium patterns on the silicon. The prebonding of the two silicon wafers is performed at room temperature. after which bonding takes place through annealing at temperatures between 120 and 400°C without affecting the performance of the electronic circuitry. The bonding is sufficiently strong for microsensor applications. 相似文献
88.
Treatment with beta-blockers has been reported to be associated with the development of hypertriglyceridemia. The etiology, even the existence, of this phenomenon is controversial. The purpose of our study was to examine whether the nonselective beta-blocker propranolol causes hypertriglyceridemia in the rat and whether its action is mediated by the modulation of lipoprotein lipase (LPL) messenger RNA (mRNA) accumulation or activity. LPL activity was assayed in fresh tissue by incubation with tritiated triglycerides. LPL mRNA was quantified in total RNA by slot-blot analysis using a mouse LPL complementary DNA probe. We have conducted three series of experiments in unanaesthetized rats in order to study the effects of different single doses of propranolol (1.5 to 6 mg i.p.) and different durations of treatment (15 min to 4 wk). We measured triglyceride and cholesterol levels in plasma as well as the LPL activity and mRNA levels in the heart and adipose tissue before and after propranolol administration. In these experiments we did not find any significant decrease in either the activity or the amount of mRNA of lipoprotein lipase nor was there any change in plasma lipids following treatment. Our results lead us to the conclusion that the nonselective beta-blocker propranolol affects neither the activity nor the mRNA level of LPL in the rat. 相似文献
89.
Ralf Keller Fredrik Alriksson Zoltán Richárd Turányi György Miklós 《Wireless Personal Communications》2005,33(3-4):217-225
The mobile network evolution from second generation to third generation systems has opened possibilities for inclusion of new technologies both in the network infrastructure as well as on the radio access. Within this paper, we concentrate on the evolution of the network infrastructure towards a future mobile network that balances the demand for increased flexibility with the necessity of limiting system complexity. Based on existing architectures, to lower complexity such as layered architecture for the core network and mobile packet backbone, we describe one possible evolution path for the control layer. Our approach is a step towards a control space that includes packetpipe control functions for a multitude of packetpipes. Such control function needs to be supported in the heterogeneous networks of today and the future. 相似文献
90.
The purpose of this paper is to analyze the costs for reducing CO2 emissions in the power-generating sectors in Croatia, the European part of Russia, Macedonia, Serbia and the Ukraine in 2020 by using a linear programming model. The model takes into account the impact of technology learning and is based on the underlying assumptions of the so-called RAINS model frequently used to assess the potential and the costs for reducing air pollution in Europe. The results based on an exogenously given 15 percent reduction target for CO2 emissions show that the marginal cost for switching from a carbon-intense fuel to either a low-carbon or to a renewable energy source differs significantly among the countries. The marginal costs range from 4 to 90€ per ton CO2, and are mainly due to country differences in the availability of renewables, existing technologies and costs. The results also indicate that although it is clear that the Eastern European countries are not homogeneous in terms of CO2 abatement potential and costs, no general conclusions can be made of the region. This may have important implications for future JI/CDM activities. For instance, risk factors such as policy uncertainty and institutional obstacles may become crucial in determining the future allocation of JI/CDM projects across the region. 相似文献