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41.
On the basis of absorption measurements in the near-infrared (NIR) spectral range, a new method for the quantification of the ethanol content of beer is presented. Instead of the multivariate calibration models most commonly employed in NIR spectroscopic works, we use interpretive difference spectroscopy: Two wavelengths are selected according to the assignment of the absorption bands of the main substances of content of beer in the NIR region, and the difference between the absorbances at these wavelengths is used for ethanol quantification. Absorption spectra of the dominating beer ingredients are discussed and the calibration procedure with ethanol/water mixtures is shown. Robustness against the carbohydrate content of beer samples was demonstrated by analyzing solutions of ethanol and maltose in water. Validation of the method was performed with various beer samples with an ethanol concentration range between 0.5 and 7.7 vol %. The pertinent advantage of the procedure developed in this work is the indication that the results are independent from seasonal variations of the ingredients, which is of high interest for products with natural ingredients such as beer. 相似文献
42.
Tanner RJ Bartlett DT Hager LG Jones LN Molinos C Roberts NJ Taylor GC Thomas DJ 《Radiation protection dosimetry》2004,110(1-4):763-767
Improvements have been made to the Monte Carlo modelling used to calculate the response of the neutron survey instruments most commonly used in the UK, for neutron energies up to 20 MeV. The improved modelling of the devices includes the electronics and battery pack, allowing better calculations of both the energy and angle dependence of response. These data are used to calculate the response of the instruments in rotationally and fully isotropic, as well as unidirectional fields. Experimental measurements with radionuclide sources and monoenergetic neutron fields have been, and continue to be made, to test the calculated response characteristics. The enhancements to the calculations have involved simulation of the sensitivity of the response to variations in instrument manufacture, and will include the influence of the user and floor during measurements. The practical implications of the energy and angle dependence of response, variations in manufacture, and the influence of the user are assessed by folding the response characteristics with workplace energy and direction distributions. 相似文献
43.
For the altitude range and inclination of the International Space Station (ISS), secondary neutrons can be a major contributor to dose equivalent inside a spacecraft. The exact proportion is very dependent on the amount of shielding of the primary galactic cosmic radiation and trapped particles, but is likely to lie in the range of 10-50%. Personal neutron dosemeters of simple design, processed using simple techniques developed for personal dosimetry, may be used to estimate this neutron component. 相似文献
44.
45.
In this paper, we study the problem of estimating correlated multiple-input multiple-output (MIMO) channels in the presence of colored interference. The linear minimum mean square error (MMSE) channel estimator is derived and the optimal training sequences are designed based on the MSE of channel estimation. We propose an algorithm to estimate the long-term channel statistics needed for the construction of the optimal training sequences. We also design an efficient scheme to feed back the required information to the transmitter where we can approximately construct the optimal sequences. Numerical results show that the optimal training sequences provide substantial performance gain for channel estimation when compared with other training sequences 相似文献
46.
Lidija Mandic Sonja Grgic Mislav Grgic 《International journal of imaging systems and technology》2007,17(4):244-251
In this article, the corresponding‐color data for complex images reproduced on different media were obtained by simultaneous matching using an adjustment method. In our experiment printed color images and images displayed on a monitor were compared in different viewing conditions. The viewing condition varied in surround relative luminance and background. The experimental data show that surround relative luminance has little influence on color matching between printed and monitor images while changes in background modify color appearance. These results were used to evaluate different chromatic adaptation transforms (CAT). We found that for the same viewing conditions the SHARP transform shows the best agreement between the experimental and predicted data. SHARP transform can not predict accurately corresponding colors for blue and black regions. Therefore, we proposed new CAT that shows better characteristics than other transforms for cyan, green, and black colors and similar characteristics for other colors. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 244–251, 2007 相似文献
47.
Organizations should look at humans as multilayered, not only as professional entities. In synergy, not only individually, we define humans as: (1) physical, (2) mental, (3) social, (4) spiritual, and (5) economic entities, marked by requisitely holistic patterns of relatively permanent characteristics, due to which individuals differ from each other; they differ also as specialized professionals. All these and other attributes form synergies. On this basis, the behavior of individuals who are willing to practice interdisciplinary cooperation becomes socially responsible and they have a high level of well-being.Individuals as well as organizations seek requisite personal holism (RPH) on the one hand and psychic well-being (PWB) on the other hand. Thus, individuals implement individual techniques and organizations implement special strategies, programs, and actions in the frame of human resource management (HRM). That is how organizations in the frame of HRM, more specifically in the frame of management well-being, are developing special programs for managing PWB. These programs are based on their RPH and organizations might help employees to feel respected and valued in their work settings, without regard to their culture, religion, ethnicity, gender, age, disability, or other individual differences. The most-often applied programs of the kind include: (1) stress management programs, (2) diversity management programs, (3) wellness programs, (4) employee assistance programs, and (5) programs for personal growth. 相似文献
48.
Wild-type chloroperoxidase catalyzes the efficient chiral epoxidation of secondary olefins but is rapidly inactivated in a mechanism-based suicide reaction when incubated with hydrogen peroxide and primary olefins. Directed evolution mutants of chloroperoxidase have now been isolated that are resistant to suicidal inactivation. Plasmid vectors containing error-prone copies of the chloroperoxidase gene and a hygromycin B resistance marker gene have been used to transform Caldariomyces fumago spheroplasts and produce mutant libraries. The mutant library clones were screened for their ability to resist mechanism-based inactivation by allylbenzene. Four generations of PCR-based random mutagenesis and screening yielded mutants that were completely resistant to the suicide-inactivation reaction. Rather surprisingly, the fourth generation mutant developed enhanced epoxidation activity in addition to resistance to allylbenzene inactivation. These initial results suggest that the directed evolution technique can be used to produce chloroperoxidase variants that can further exploit the potential of chloroperoxidase for the synthesis of chiral intermediates. 相似文献
49.
The effect of temperature on gross slip fretting wear of cold-sprayed nickel coatings on Ti6Al4V interfaces 总被引:1,自引:0,他引:1
Fretting wear is an accumulation of damage that occurs at component interfaces that are subjected to high contact stresses coupled with low-amplitude oscillation. In metallic contacts, surface oxides, adhesion, and material transfer play a primary role in the initial stages of fretting wear degradation. Given these behaviors, the focus of this study was to determine the effect of temperature on inter-metallic fretting wear between Ti6Al4V (titanium, 6% aluminum, 4% vanadium) and cold-sprayed, commercially pure nickel coatings. The results presented herein show that increased temperature decreases friction through the formation of a uniform NiO layer, and by a reduction of Ni2O3 in contacts. In addition, it was found that a localized minimum friction coefficient is achieved at approximately 300 °C, above which friction increases slightly due to annealing of the cold-sprayed coatings. 相似文献
50.