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111.
Synthesis of Nano‐ and Micro‐Scale Topographies by Combining Colloidal Lithography and Glancing Angle Deposition (GLAD)
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112.
A multi-source forest inventory (MSFI) method has been developed for use in the Norwegian National Forest Inventory (NFI). The method is based on a k-nearest neighbour rule and uses field plots from the NFI, land cover maps, and satellite image data from Landsat Thematic Mapper. The inventory method is used to produce maps of selected forest variables and to estimate the selected forest variables for large areas such as municipalities. In this study, focus has been on the qualitative variables ‘dominating species group’ and ‘development class’ because these variables are of central interest to forest managers. A mid-summer Landsat 5 TM scene was used as image data, and all NFI plots inside the scene were used as a reference dataset. The relationship between the spectral bands and the forest variables was analysed, and it was found that the levels of association were low. A leave-one-out method based on the reference dataset was used to estimate the pixel-level accuracies. They were found to be relatively low with 63% agreement for species groups. An independent control survey was available for a municipality and estimates from the MSFI were compared to it. The levels of error were quite high. It was concluded that the large area estimates were biased by the reference dataset. 相似文献
113.
Steen B. Schougaard Niels Reitzel Kristian Kjaer Torben R. Jensen Ramon Colorado Jr. J.-H. Choi David Derro John T. McDevitt 《Thin solid films》2007,515(23):8424-8429
A self-assembled monolayer of CF3(CF2)3(CH2)11NH2 atop the (001) surface of the high-temperature superconductor YBa2Cu3O7-x was imaged by atomic force microscopy (AFM). The AFM images provide direct 2D-structural evidence for the epitaxial 5.5 Å square √2 × √2R45° unit cell previously predicted for alkyl amines by molecular modeling [J.E. Ritchie, C.A. Wells, J.-P. Zhou, J. Zhao, J.T. McDevitt, C.R. Ankrum, L. Jean, D.R. Kanis, J. Am. Chem. Soc. 120 (1998) 2733]. Additionally, the 3D structure of an analogous Langmuir monolayer of CF3(CF2)9(CH2)11NH2 on water was studied by grazing-incidence X-ray diffraction and specular X-ray reflectivity. Structural differences and similarities between the water-supported and superconductor-localized monolayers are discussed. 相似文献
114.
Kathrin Sundberg Kristian Dreij Bengt Jernström Albrecht Seidel 《Polycyclic Aromatic Compounds》2013,33(3-4):947-953
V79MZ cells expressing human glutathione transferases (hGST) have been constructed and used to study glutathione (GSH) conjugation of anti -diol epoxides (DEs) of dibenzo[ a,l ]pyrene ( DBPDE ), and benzo[ a ]pyrene ( BPDE ). Cells expressing hGSTM1-1 were more effective with ( m )- anti - DBPDE than hGSTP1-1. The opposite was observed with (+)- anti - BPDE . Rates of cellular DE uptake and solvolysis in conjunction with oil/water partition coefficients were used to calculate the amount of DEs available for GST-catalyzed conjugation in the cells. Using this information and the known values of k cat /K M for (+)- anti - BPDE and ( m )- anti - DBPDE with purified hGSTs, it was calculated that up to 3% of available (+)- anti - BPDE forms GSH conjugates whereas the corresponding figure with the less reactive and more lipophilic ( m )- anti - DBPDE was about 19%. In part, the lower fraction of (+)- anti -BPDE conjugated in cells is probably due to rapid and competing reactions with cellular constituents. 相似文献
115.
The energy policy in Europe regarding buildings and the energy efficiency sector are regulated by two directives: 2002/91/CE - EPBD and 2006/32/CE - EEESD
[1] and [2].The CEN has elaborated a standard to revise all European normatives about building energy performance and HVAC plants. The “CEN Umbrella” CEN/TR 15615 [3] includes a new version of EN ISO 13790:2008 [4] and a new standard about heating plant, use and contributions of renewable energy sources. Furthermore, the CEN Standard provides a software version for technicians.In this paper we present a Round Robin Test between a selection of softwares applied to an Italian case study. The selected calculation methodologies, range from research packages to extra-simplified software. Furthermore, the Italian procedure described in UNI TS 11300 [5] has been analyzed and considered as the reference for all other calculation methodologies.The results of the Round Robin Test show the relationship between thoroughness of data input and energy evaluation accurancy. The more the input data is affected by uncertainty, the less precise is the energy efficiency calculation. On the other hand the energy performance of building evaluation accurancy depends on the aim of the simulation: the energy audit, the energy design or the energy labeling (certification). 相似文献
116.
In this paper a combination of NIR spectroscopy and FTIR and Raman microspectroscopy was used to elucidate the effects of different salts (NaCl, KCl and MgSO4) on structural proteins and their hydration in muscle tissue. Multivariate multi-block technique Consensus Principal Component Analysis enabled integration of different vibrational spectroscopic techniques: macroscopic information obtained by NIR spectroscopy is directly related to microscopic information obtained by FTIR and Raman microspectroscopy. Changes in protein secondary structure observed at different concentrations of salts were linked to changes in protein hydration affinity. The evidence for this was given by connecting the underlying FTIR bands of the amide I region (1700–1600 cm−1) and the water region (3500–3000 cm−1) with water vibrations obtained by NIR spectroscopy. In addition, Raman microspectroscopy demonstrated that different cations affected structures of aromatic amino acid residues differently, which indicates that cation–π interactions play an important role in determination of the final structure of protein molecules. 相似文献
117.
Kristian Tønder 《Tribology International》2010,43(12):2303-2307
Surface texturing effects on the properties of pivoted plane hydrodynamic bearings are studied by numerical simulation based on the Reynolds equation. The texturing, in the form of dimples, covers the whole bearing surface. The calculations employed are more dependable than those previously used by the author. It is found that under certain operating conditions, friction is increased but the specific load capacity is increased even more. This results in a reduction in the coefficient of friction. Dynamic coefficients such as lubricant film stiffness and damping may also be improved under certain conditions. However, it is found that conditions giving high stiffness also give high coefficients of friction. 相似文献
118.
119.
Kristian Petersen Nørgaard Kim Dam-Johansen Pere Català Søren Kiil 《Progress in Organic Coatings》2014
Protection of steel structures, using so-called intumescent coatings, is an efficient and space saving way to prolong the time before a building, with load bearing steel constructions, collapses in the event of a fire. In addition to the intumescent coating, application of a primer may be required, either to ensure adhesion of the intumescent coating to the steel or to provide corrosion resistance. It is essential to document the performance of the intumescent coating together with the primer to ensure the overall quality of coating system. In the present work, two epoxy primers were used to investigate the potential failure mechanism of a primer applied prior to an intumescent coating. The analysis was carried out using; (1) gas-fired test furnace, (2) a specially designed electrically heated oven, and (3) thermo gravimetric analysis. When tested below an acrylic intumescent coating, exposed to a gas-fired furnace following the ISO834 fire curve (a so-called cellulosic fire), one of the primers selected performed well and the other poorly. From tests in the electrically heated oven, it was found that both primers were sensitive to the film thickness employed and the presence of oxygen. At oxygen-rich conditions, higher primer thicknesses gave weaker performance. In addition, a color change from red to black was observed in nitrogen, while the color remained red in the oxygen–nitrogen mixture. In summary, the results suggest that an adequate choice of primer, primer thickness, and intumescent coating is essential for a good performance of an intumescent coating system. 相似文献
120.
Mølhave K Gudnason SB Pedersen AT Clausen CH Horsewell A Bøggild P 《Nano letters》2006,6(8):1663-1668
We present repeated structural and electrical measurements on individual multiwalled carbon nanotubes, alternating between electrical measurements under ambient conditions and transmission electron microscopy (TEM). The multiwalled carbon nanotubes made by chemical vapor deposition were manipulated onto cantilever electrodes extending from a specially designed microfabricated chip. Repeated TEM investigations were then made of the progressive destruction of the nanotube structure induced by Joule heating in air. The electrical measurements indicate that the studied nanotubes behave as diffusive conductors with remarkably predictable electrical properties despite extensive structural damage. 相似文献