| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Chen, K., et al.
(författare)
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Ti deficiency effect on the dielectric response of CaCu3Ti4O12 ceramics
- 2007
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Ingår i: Solid State Communications. - : Elsevier. - 0038-1098 .- 1879-2766. ; 141:8, s. 440-444
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Tidskriftsartikel (refereegranskat)abstract
- Single phase ceramics CaCu3Ti4.0O12 and CaCu3Ti3.9O12 have been prepared using the traditional solid-state reaction method. Compared with the stoichiometric ceramics CaCu3Ti4.0O12, Ti-deficient ceramics CaCu3Ti3.9O12 have the larger lattice parameter, the higher force constant, and smaller dielectric constant and the lower dissipation factor, although their fundamental characters of dielectric response are similar. Their characteristic relaxation frequencies are not well fitted with the Arrhenius Law but a tentatively supposed relation. With the Cole-Cole Law, the fitted broadened factors of dissipation peaks are 0.5433 and 0.8651 for CaCu3Ti3.9O12 and CaCu3Ti4.0O12, respectively. All facts mentioned above imply that mutually correlated motion of Ti ions or defects may be expected to be responsible for the giant dielectric constant and high dissipation factor of CaCu3T4.0O12. (c) 2006 Elsevier Ltd. All rights reserved.
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| 3. |
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| 4. |
- Liu, C., et al.
(författare)
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Thermodynamic Analysis for Synthesis of Advanced Materials
- 2009
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Ingår i: Molecular Thermodynamics of Complex Systems. - Berlin : Encyclopedia of Global Archaeology/Springer Verlag. - 9783540691143 ; , s. 193-270
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, thermodynamic modeling for materials-oriented chemical engineering systems were investigated in order to solve critical scientific problems, such as the material structure, chemical properties, thermodynamic properties, and transfer behaviors on the interfaces or under confined circumstances. On the basis of the theory and approaches of chemical engineering, and the principles of chemical engineering thermodynamics and transfer processes, molecular simulations were combined with modern physical characterization methods to study thermodynamic modeling in materials-oriented chemical engineering processes.
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| 5. |
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| 6. |
- Chen, K., et al.
(författare)
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High permittivity in zr doped NiO ceramics
- 2007
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Ingår i: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 102:3, s. 034103-
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Tidskriftsartikel (refereegranskat)abstract
- We report on measurements of the dielectric permittivity of NiO-based ceramics doped with Zr (ZNO). Samples were prepared by the traditional solid-state reaction method. The concentration of Zr has an effect on the dielectric properties of ZNO ceramics. High permittivity values (similar to 10(4)) were observed which remain almost constant from 200 K to 350 K at low frequencies. The high-dielectric-constant response of the ZNO ceramics is attributed mainly to a grain boundary (internal) barrier layer capacitance. (c) 2007 American Institute of Physics.
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| 7. |
- Chen, X. Y., et al.
(författare)
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Application of weak ferromagnetic BiFeO3 films as the photoelectrode material under visible-light irradiation
- 2007
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Ingår i: Applied Physics Letters. - : American Institute of Physics (AIP). - 0003-6951 .- 1077-3118. ; 91:2, s. 022114-
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Tidskriftsartikel (refereegranskat)abstract
- BiFeO3 films prepared by pulsed laser deposition on Pt/TiO2/SiO2/Si substrates were studied as photoelectrode for water splitting. Under visible-light irradiation, the photocurrent intensity of the polycrystalline BiFeO3 film was found to double that of the amorphous one in a three-electrode cell. The incident photon to current conversion efficiency for the polycrystalline BiFeO3 electrode was approximately 16% at 350 nm and 7% at 530 nm at 1.5 V (versus saturated calomel electrode). The ferromagnetism of the amorphous BiFeO3 film was an order of magnitude weaker than that of the polycrystalline one, supporting the "size effect" explanation for magnetic origin. (C) 2007 American Institute of Physics.
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| 8. |
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| 9. |
- Feng, X. M., et al.
(författare)
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Growth of lactic acid bacteria and Rhizopus oligosporus during barley tempeh fermentation
- 2005
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Ingår i: International Journal of Food Microbiology. - Amsterdam, Netherlands : Elsevier. - 0168-1605 .- 1879-3460. ; 104:3, s. 249-256
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Tidskriftsartikel (refereegranskat)abstract
- The zygomycete Rhizopus oligosporus is traditionally used to ferment soybean tempeh, but it is also possible to ferment other legumes and cereals to tempeh, The traditional soybean tempeh harbours a multitude of microorganisms with potentially beneficial or detrimental effects on quality. Lactic acid bacteria (LAB) have positive effects on the safety of soybean tempeh, but the effects of LAB on R. oligosporus growth have not been investigated. We have developed a cereal grain tempeh by fermenting pearled barley with R. oligosporus ATCC 64063. Four LAB species, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus reuteri and Lactococcus lactis were assessed for their growth abilities and their effects on R. oligosporus growth during barley tempeh fermentation. Growth of LAB was assayed as colony forming units (cfu), while growth of R. oligosporus was measured as ergosterol content and hyphal length. The two fungal measurements highly correlated (r=0.83, P < 0.001, n = 90). The ergosterol content of fungal mycelia ranged from 11.7 to 30.1 mg/g fungal dry matter. L. plantarum multiplied from 4.8 to 7.4 log cfu/g dry tempeh and L. fermentum increased from 4.4 to 6.8 log cfu/g during 24 h incubation at 35 degrees C. L. reuteri and L. lactis had significantly slower growth, with increases from 4.8 to 5.6 log cfu/g and 5.0 to 5.4 log cfu/g, respectively. The growth of R. oligosporus and the final pH (4.9) in barley tempeh were not significantly influenced by any of the LAB investigated.
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| 10. |
- Feng, X. M., et al.
(författare)
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Image analysis for monitoring the barley tempeh fermentation process
- 2007
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Ingår i: Journal of Applied Microbiology. - Oxon, United Kingdom : Oxford University Press (OUP). - 1364-5072 .- 1365-2672. ; 103:4, s. 1113-1121
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To develop a fast, accurate, objective and nondestructive method for monitoring barley tempeh fermentation. Methods and Results: Barley tempeh is a food made from pearled barley grains fermented with Rhizopus oligosporus. Rhizopus oligosporus growth is important for tempeh quality, but quantifying its growth is difficult and laborious. A system was developed for analysing digital images of fermentation stages using two image processing methods. The first employed statistical measures sensitive to image colour and surface structure, and these statistical measures were highly correlated (r = 0.92, n = 75, P < 0.001) with ergosterol content of tempeh fermented with R. oligosporus and lactic acid bacteria (LAB). In the second method, an image-processing algorithm optimized to changes in images of final tempeh products was developed to measure number of visible barley grains. A threshold of 5 visible grains per Petri dish indicated complete tempeh fermentation. When images of tempeh cakes fermented with different inoculation levels of R. oligosporus were analysed the results from the two image processing methods were in good agreement. Conclusion: Image processing proved suitable for monitoring barley tempeh fermentation. The method avoids sampling, is nonintrusive, and only requires a digital camera with good resolution and image analysis software. Significance and Impact of the Study: The system provides a rapid visualization of tempeh product maturation and qualities during fermentation. Automated online monitoring of tempeh fermentation by coupling automated image acquisition with image processing software could be further developed for process control.
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