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11.
We consider the quantum optical eight-port homodyne detection scheme in the case that each of the associated photon detectors is assigned with a different quantum efficiency. We give a mathematically rigorous and strictly quantum mechanical proof of the fact that the measured observable (positive operator measure) in the high-amplitude limit is a smearing of the covariant phase space observable related to the ideal measurement, that is, the measurement performed with fully efficient detectors. The result is proved for an arbitary parameter field. Furthermore, we investigate some properties of the measured observable. In particular, we show that detector inefficiencies do not affect the observable's ability to distinguish between different states. 相似文献
12.
Jiale Feng Lupeng Yang Alexander S. Romanov Jirawit Ratanapreechachai Antti‐Pekka M. Reponen Saul T. E. Jones Mikko Linnolahti Timothy J. H. Hele Anna Khler Heinz Bssler Manfred Bochmann Dan Credgington 《Advanced functional materials》2020,30(9)
Carbene‐metal‐amides (CMAs) are a promising family of donor–bridge–acceptor molecular charge‐transfer (CT) emitters for organic light‐emitting diodes. A universal approach is demonstrated to tune the energy of their CT emission. A blueshift of up to 210 meV is achievable in solid state via dilution in a polar host matrix. The origin of this shift has two components: constraint of thermally‐activated triplet diffusion, and electrostatic interactions between guest and polar host. This allows the emission of mid‐green CMA archetypes to be tuned to sky blue without chemical modifications. Monte‐Carlo simulations based on a Marcus‐type transfer integral successfully reproduce the concentration‐ and temperature‐dependent triplet diffusion process, revealing a substantial shift in the ensemble density of states in polar hosts. In gold‐bridged CMAs, this shift does not lead to a significant change in luminescence lifetime, thermal activation energy, reorganization energy, or intersystem crossing rate. These discoveries offer new insight into coupling between the singlet and triplet manifolds in CMA materials, revealing a dominant interaction between states of CT character. The same approach is employed using materials which have been chemically modified to alter the energy of their CT state directly, shifting the emission of sky‐blue chromophores into the practical blue range. 相似文献
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Joseph Hamuyuni Niko Hellstén Guven Akdogan Pekka Taskinen 《Journal of the American Ceramic Society》2015,98(1):320-323
We present experimental results for the liquidus of the pseudo binary system Cu2O–CaO at metallic copper saturation up to 1698 K in steps of 25 K. In this study, we quantified the liquidus (on the CaO side of the binary) by the equilibration, quench, and analysis technique, with Cu2O, CaO, and Cu as the only primary crystalline phases. Experiments were conducted in an atmosphere of pure argon up to the critical temperature (1618 K) in the Cu–O system. Above this temperature, experiments were performed at a fixed oxygen pressure of (PO2 = 1.01 kPa). Equilibrated specimens were quenched in ice‐cold water. We then quantified the liquid chemical compositions by means of energy‐dispersive X‐ray spectroscopy and electron probe micro‐analyzer. Results from this study reveal that below the critical point, some previous studies have overestimated CaO solubility amounts in the molten phase of the system, by up to 4.35 wt% CaO. Thermodynamic modeling of systems containing this binary should therefore also account for this variance. 相似文献
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Ming Yang Suvi Kuittinen Markku Keinänen Jouko Vepsäläinen Henrik Romar Pekka Tynjälä Ulla Lassi Ari Pappinen 《Chemical Engineering Research and Design》2014
In this study, pretreatment liquor of acid-stored green and yellowish barley silage was used for fermentative acetone–butanol–ethanol (ABE) production. Further, the catalytic oxidation of biobutanol over Pt catalysts was studied to investigate the behaviour of butanol as a fuel in the combustion engine. After the hydrothermal treatment of green and yellowish barley silage followed by enzymatic hydrolysis, approximately 88% and 100% of the available sugars were recovered, respectively. Batch fermentations of pretreatment barley silage liquor, supplemented with gelatinised barley grain, showed good fermentability with total ABE concentrations of 9.0 g/L and 10.9 g/L. Butanol yields of 0.20, 0.17 and ABE yields of 0.28, 0.26 (g/g monosaccharide) were obtained, respectively. In catalytic activity measurements, the conversion of biobutanol became appreciable in the 120–140 °C range, whereas conversions greater than 95% were obtained over 200 °C. Selectivities were also high, although formation of by-products, such as butyraldehyde, was observed. 相似文献
17.
Fiseha Tesfaye Dmitry Sukhomlinov Daniel Lindberg Mykola Moroz Pekka Taskinen Leena Hupa 《Mineral Processing and Extractive Metallurgy Review》2019,40(1):67-78
In this article, oxidation processes of Ag-Bi-Sb-based phases were investigated. Synthesized AgBiS2 and AgSbS2-Sb2S3-Sb samples were thermally analyzed in synthetic air by applying the simultaneous DSC-TGA analysis technique. The oxidation processes at PO?=0.2 atm and T<1173 K were observed to take place in many-step sequence of various reactions with an overall reaction 2AgMeS2 + 5.5O2(g) ? 2Ag + Me2O3 + 4SO2(g), where Me=(Bi,Sb). Oxidations of AgBiS2, Sb2S3, and AgSbS2 were observed to begin above 549±2K, 610±2K, and 733±2K, respectively. Furthermore, oxidation processes of AgBi3S5 and Ag3SbS3 were estimated, and thermodynamic functions for the overall oxidation reactions were calculated and discussed. 相似文献
18.
Modern paper machines are equipped with heat recovery systems that transfer heat from the humid exhaust air of the paper machine’s dryer section to different process streams. As a result of process changes, the heat recovery systems may operate in conditions far from the original design point, creating a significant potential for energy efficiency improvement. In this paper we demonstrate this potential with a case study of three operating paper machines. Both operational and structural improvement opportunities are examined. Since the existing retrofit methodologies for heat exchanger networks can not be applied to cases with condensing air, we use thermodynamic simulation models presented earlier to assess the effects of possible changes on the existing heat recovery systems. In order to reduce the required processing time of the simulation models, only a limited number of pre-screened retrofit designs are considered. The pre-screening is carried out on the basis of guidelines presented earlier. The analysis in the case mill revealed savings of 110 GWh/a in process heat with profitable investments. According to the follow-up study, the investments carried out have resulted in 12% lower fuel use and 24% lower CO2 emissions. The results imply that all operating paper machines should be similarly examined. 相似文献
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20.
Five silane blends were evaluated as experimental adhesion-promoter primers. First, five organosilane monomers (silicon esters),
3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, tetrakis-(2-ethyloxyethoxy)silane and bis-[3-(triethoxysilyl)propyl]tetrasulfide, were diluted to 1% (v/v) and blended with a non-functional cross-linking silane, 1,2-bis-(triethoxysilyl)ethane (1%), in 95% ethanol. After activation, each blend was applied to silica-coated Ti coupons. A resin
based on bis-phenol-A-diglycidyldimethacrylate was then bonded and photo-polymerized as stubs to the pretreated Ti coupons. Half of the
specimens were stored in dry conditions and half were artificially aged by thermo-cycling. The primers containing 3-acryloxypropyltrimethoxysilane
and 3-methacryloxypropyltrimethoxysilane produced significantly higher shear bond strength values than the control silane,
a standard pre-activated product used in clinical dentistry. 相似文献