| 1. |
- Forzati, Marco, et al.
(författare)
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Performance analysis of single-MZM APRZ transmitter
- 2005
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Ingår i: IET Conference Publications. - : Institution of Engineering and Technology. ; , s. 663-664
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Konferensbidrag (refereegranskat)abstract
- We present the first numerical study of 67%-duty-cycle single-MZM APRZ, comparing it with 33% RZ, 33% APRZ and standard CSRZ. This transmitter is shown to combine CSRZ implementation simplicity with the improved nonlinear tolerance of π/2-APRZ.
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| 2. |
- Forzati, Marco, et al.
(författare)
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Performance Analysis of Single-MZM APRZ Transmitters
- 2006
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Ingår i: IEEE transactions on intelligent transportation systems (Print). - 1524-9050 .- 1558-0016. ; 24, s. 2006-14
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, an efficient single Mach-Zender modulator (MZM) implementation of alternate-phase return to zero (APRZ), which combines carrier-suppressed return to zero (CSRZ)'s ease of implementation with APRZ's nonlinear tolerance, is analyzed. In particular, the first numerical study of 67%-duty-cycle single-MZM APRZ over a 40-Gb/s 5 × 100-km link, in terms of nonlinear, dispersion, and filtering tolerance, comparing it with 33% RZ, 33% APRZ, and standard 67% CSRZ, is presented. The results show that APRZ with phase shift close to π/2 is the optimum choice, independent of specific transmitter implementation. A new mechanism is also discovered, based on the interference of ghost pulses with the original pulse train, which improves the nonlinear tolerance of CSRZ in a 40-Gb/s transmission
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| 3. |
- Jonauskaite, Domicele, et al.
(författare)
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A comparative analysis of colour–emotion associations in 16–88-year-old adults from 31 countries
- 2024
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Ingår i: British Journal of Psychology. - : John Wiley and Sons Ltd. - 0007-1269 .- 2044-8295. ; 115:2, s. 275-
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Tidskriftsartikel (refereegranskat)abstract
- As people age, they tend to spend more time indoors, and the colours in their surroundings may significantly impact their mood and overall well-being. However, there is a lack of empirical evidence to provide informed guidance on colour choices, irrespective of age group. To work towards informed choices, we investigated whether the associations between colours and emotions observed in younger individuals also apply to older adults. We recruited 7393 participants, aged between 16 and 88 years and coming from 31 countries. Each participant associated 12 colour terms with 20 emotion concepts and rated the intensity of each associated emotion. Different age groups exhibited highly similar patterns of colour–emotion associations (average similarity coefficient of.97), with subtle yet meaningful age-related differences. Adolescents associated the greatest number but the least positively biased emotions with colours. Older participants associated a smaller number but more intense and more positive emotions with all colour terms, displaying a positivity effect. Age also predicted arousal and power biases, varying by colour. Findings suggest parallels in colour–emotion associations between younger and older adults, with subtle but significant age-related variations. Future studies should next assess whether colour–emotion associations reflect what people actually feel when exposed to colour.
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| 4. |
- Lucisano, Marco F. C., et al.
(författare)
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The role of evaporative dewatering in impulse pressing
- 2003
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Ingår i: Tappi Journal. - 0734-1415. ; 2:3, s. 26-32
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Tidskriftsartikel (refereegranskat)abstract
- The objective was to link heat transfer to water removal mechanisms, specifically evaporative dewatering, in impulse pressing experiments. Two independent laboratory devices - a platen press and a shoe press - were used to impulse press fiber webs made from softwood bleached kraft (SBK) over a range of basis weights (20-200 g/m2). In the platen press experiments, evaporative dewatering was evaluated by comparing the measured heat input to the amount of heat theoretically required to vaporize the water in excess of unheated wet pressing. Evaporative dewatering was found to be most pronounced for lightweight sheets, and enhanced dewatering can be attributed to this mechanism and other high-temperature mechanisms for basis weights above 60 g/m2. In the shoe press experiments, a composite sheet of five 30-g/m2 webs was used to evaluate profiles for resulting dryness, density, and water retention value (WRV) in the thickness direction. Evaporative effects were confined principally to the layer directly in contact with the heated surface. Application: A better understanding of the water removal mechanisms in impulse pressing process may accelerate the industrial application of impulse technology.
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| 5. |
- Lucisano, Marco F. C., et al.
(författare)
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Visualization of liquid-vapor phase change phenomena in impulse technology
- 2006
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Ingår i: Tappi Journal. - 0734-1415. ; 5:6, s. 15-21
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses two unresolved aspects in the physics of impulse technology. In our initial study, we used a modified laboratory platen press to investigate contact phenomena at the interface between the wet web and the hot press. We replaced the heated press platen with a preheated glass plate and used high-speed photography to visualize the interfacial interactions. The results confirm that little or no steam is formed before the point of maximum applied load for contact times typical of industrial pressing operations (25 ms). Steam generation during the nip compression phase could be observed only for pulse lengths well beyond those encountered in industrially relevant impulse press nips (250 ms). In a complementary study, flashing phenomena were investigated in STFI's FlashLab, an experimental facility for the study of phase-change phenomena in water-saturated porous media. Model experiments under well-defined conditions showed that delamination can be prevented by an appropriate unloading strategy. Moreover, we observed that flashing-assisted displacement dewatering occurred when the hydraulic pressure was released. We discuss its significance for impulse pressing efficiency in this report.
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| 6. |
- Martin, Andrew R., et al.
(författare)
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Characterizing liquid-vapor phase change phenomena in impulse technology with resistivity probes
- 2006
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Ingår i: Tappi Journal. - 0734-1415. ; 5:5, s. 22-26
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Tidskriftsartikel (refereegranskat)abstract
- This study used resistivity probes for the dynamic detection of liquid-vapor phase change inside wet paper webs undergoing impulse pressing. The probes were made from thin copper wires insulated with a high-temperature polymeric material (overall diameter of 50 urn).The gap between the exposed ends served as the probe tip. The validity of this technique in impulse pressing experiments was demonstrated in two ways: (1) tests with both dry and wet sheets showed that the probe response was unaffected by the fiber network itself; and (2) heated trials with low applied pressure and long residence times (> 1 s) clearly showed the propagation of a vapor front through the sheet, as predicted by theory. Impulse pressing experiments were subsequently conducted with a platen press under realistic operating conditions (i.e. surface temperatures up to 300°C, nip residence times of approximately 25 ms, and maximum applied pressure around 4 MPa). Results show that steam was detected inside the sheet only upon unloading of the hot nip for the layers closest to the heated surface.
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| 7. |
- Slanina, Tomáš, et al.
(författare)
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Impact of Excited-State Antiaromaticity Relief in a Fundamental Benzene Photoreaction Leading to Substituted Bicyclo[3.1.0]hexenes
- 2020
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society. - 0002-7863 .- 1520-5126. ; 142:25, s. 10942-10954
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Tidskriftsartikel (refereegranskat)abstract
- Benzene exhibits a rich photochemistry which can provide access to complex molecular scaffolds that are difficult to access with reactions in the electronic ground state. While benzene is aromatic in its ground state, it is antiaromatic in its lowest ππ∗ excited states. Herein, we clarify to what extent relief of excited-state antiaromaticity (ESAA) triggers a fundamental benzene photoreaction: the photoinitiated nucleophilic addition of solvent to benzene in acidic media leading to substituted bicyclo[3.1.0]hex-2-enes. The reaction scope was probed experimentally, and it was found that silyl-substituted benzenes provide the most rapid access to bicyclo[3.1.0]hexene derivatives, formed as single isomers with three stereogenic centers in yields up to 75% in one step. Two major mechanism hypotheses, both involving ESAA relief, were explored through quantum chemical calculations and experiments. The first mechanism involves protonation of excited-state benzene and subsequent rearrangement to bicyclo[3.1.0]hexenium cation, trapped by a nucleophile, while the second involves photorearrangement of benzene to benzvalene followed by protonation and nucleophilic addition. Our studies reveal that the second mechanism is operative. We also clarify that similar ESAA relief leads to puckering of S1-state silabenzene and pyridinium ion, where the photorearrangement of the latter is of established synthetic utility. Finally, we identified causes for the limitations of the reaction, information that should be valuable in explorations of similar photoreactions. Taken together, we reveal how the ESAA in benzene and 6π-electron heterocycles trigger photochemical distortions that provide access to complex three-dimensional molecular scaffolds from simple reactants.
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