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161.
The ErAuxNi1−xIn (0 ≤ x ≤ 1) quasiternary compounds crystallize in the hexagonal layered crystal structure of ZrNiAl-type. ErAuIn was reported to be an antiferromagnet with TN = 3 K and magnetic moments having triangular arrangement within the basal plane (the magnetic order is described by the propagation vector ). On the contrary ErNiIn is a ferromagnet with TC = 9 K and magnetic moments pointing along the c-axis. The magnetic ordering in ErAuxNi1−xIn (0 < x < 1) solid solution, has been investigated by neutron diffractometry in the temperature range between 1.5 and 15 K. Moreover, bulk magnetic measurements have been carried out in the range 1.72–400 K. All alloys of intermediate composition were found to be antiferromagnets with TN between 4.6 and 7 K. Below 2 K their magnetic order is described by the propagation vector and magnetic moments are aligned along the c-axis. However, for alloys with 0.2 ≤ x ≤ 0.7 the propagation vector was found to turn into with increasing temperature. 相似文献
162.
In the present work, fast pyrolysis of Alternanthera philoxeroides was evaluated with a focus to study the chemical and physical characteristics of bio-oil produced and to determine its practicability as a transportation fuel. Pyrolysis of A.philoxeroides was conducted inside a semi batch quartz glass reactor to determine the effect of different operating conditions on the pyrolysis product yield. The thermal pyrolysis of A. philoxeroides were performed at a temperature range from 350 to 550 °C at a constant heating rate of 25 °C/min & under nitrogen atmosphere at a flow rate of 0.1 L/min, which yielded a total 40.10 wt.% of bio-oil at 450 °C. Later, some more sets of experiments were also performed to see the effect on pyrolysis product yield with change in operating conditions like varying heating rates (50 °C/min, 75 °C/min & 100 °C/min) and different flow rates of nitrogen (0.2, 0.3, 0.4 & 0.5 L/min). The yield of bio-oil during different heating rate (25, 50, 75 and 100 °C/min) was found to be more (43.15 wt.%) at a constant heating rate of 50 °C/min with 0.2 L/min N2 gas flow rate and at a fixed pyrolysis temperature of 450 °C. The High Heating Value (HHV) value of bio-oil (8.88 MJ/kg) was very less due to presence of oxygen in the biomass. However, the high heating value of bio-char (20.41 MJ/kg) was more, and has the potential to be used as a solid fuel. The thermal degradation of A. philoxeroides was studied in TGA under inert atmosphere. The characterization of bio-oil was done by elemental analyser (CHNS/O analyser), FT-IR, & GC/MS. The char was characterized by elemental analyser (CHNS/O analysis), SEM, BET and FT-IR techniques. The chemical characterization showed that the bio-oil could be used as a transportation fuel if upgraded or blended with other fuels. The bio-oil can also be used as feedstock for different chemicals. The bio-char obtained from A. philoxeroides can be used for adsorption purposes because of its high surface area. 相似文献
163.
Eray Baran Ryan Rohne Catherine E. French Arturo E. Schultz 《Canadian Metallurgical Quarterly》2009,14(5):319-326
Static load tests were performed on support details used at the ends of prestressed concrete pedestrian bridge girders to determine the resistance characteristics of girder supports in the direction perpendicular to the longitudinal axis of the girders. The specimens tested represent support details that have also been widely used in prestressed concrete highway bridges in Minnesota and in other states. Two specimens, one representing the free-end detail and one representing the restrained-end detail were subjected to a combination of vertical and lateral loads. The applied loading was intended to simulate the loading conditions to which the girder ends would be subjected in the event of an over-height vehicle collision with the bridge. The tests revealed two types of lateral load resisting mechanisms depending on the type of support detail. The specimen with the free-end detail resisted the lateral loading through sliding friction between the components of the support assembly. Deformation of this specimen was a combination of shear deformation of the bearing pad and sliding of various support components. The restrained-end detail exhibited larger lateral load capacity than the free-end detail due to the resistance provided by the anchor rods that were intended to prevent the lateral movement of the girder ends. Failure of the specimen with restrained-end detail was due to the concrete breakout and bending of the anchor rods. 相似文献
164.
Ya. Zhydachevskii L. Lipińska M. Baran M. Berkowski A. Suchocki A. Reszka 《Materials Chemistry and Physics》2014
Comparative study of the broadband down-conversion processes in Bi3+–Yb3+-codoped yttrium oxide (Y2O3) and various yttrium–aluminum oxides (Y3Al5O12, YAlO3 and Y4Al2O9) has been performed from the point of view of search for materials suitable for enhancement of efficiency of silicon solar cells. The studied materials in the form of nanopowders have been synthesized by sol–gel method and characterized by X-ray powder diffraction, scanning electron microscopy and luminescence techniques. Relative down-conversion efficiency for studied materials has been estimated. It was shown that optimal concentration of Yb3+ ions should be 2–4 at.% simultaneously with Bi3+ ions in the amount of about 1 at.%. Such dopants content provides the highest emission intensity of Yb3+ ions in near-infrared when excited into Bi3+ ions absorption in ultraviolet. Perspectives of the studied materials for enhancement of silicon solar cells are discussed. 相似文献
165.
Photophysics of Molecular‐Weight‐Induced Losses in Indacenodithienothiophene‐Based Solar Cells
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Nicola Gasparini Athanasios Katsouras Mamantos I. Prodromidis Apostolos Avgeropoulos Derya Baran Michael Salvador Stefanie Fladischer Erdmann Spiecker Christos L. Chochos Tayebeh Ameri Christoph J. Brabec 《Advanced functional materials》2015,25(30):4898-4907
The photovoltaic performance and optoelectronic properties of a donor–acceptor copolymer are reported based on indacenodithienothiophene (IDTT) and 2,3‐bis(3‐(octyloxy)phenyl)quinoxaline moieties (PIDTTQ) as a function of the number‐average molecular weight (Mn). Current–voltage measurements and photoinduced charge carrier extraction by linear increasing voltage (photo‐CELIV) reveal improved charge generation and charge transport properties in these high band gap systems with increasing Mn, while polymers with low molecular weight suffer from diminished charge carrier extraction because of low mobility–lifetime (μτ) product. By combining Fourier‐transform photocurrent spectroscopy (FTPS) with electroluminscence spectroscopy, it is demonstrate that increasing Mn reduces the nonradiative recombination losses. Solar cells based on PIDTTQ with Mn = 58 kD feature a power conversion efficiency of 6.0% and a charge carrier mobility of 2.1 × 10?4 cm2 V?1 s?1 when doctor bladed in air, without the need for thermal treatment. This study exhibits the strong correlations between polymer fractionation and its optoelectronics characteristics, which informs the polymer design rules toward highly efficient organic solar cells. 相似文献
166.
Sema Bağdat Eda Köse Baran Feyzullah Tokay 《International Journal of Food Science & Technology》2014,49(2):392-398
Fractionation analyses are essential to investigate the effects of dietary constituents on bioavailability of elements. A sequential separation procedure has been applied for elemental fractionation patterns in infant formula, coffee cream, milk powder, whey powder and rice flour. The protein, lipid and serum fractions were separated successfully, and fractions were analysed for various essential (Fe, Cu, Zn, Mn, Mg, Ca, Cr and Co) and nonessential (Ni, V, Al, Mo, Pb, Sn, Ba and Cd) elements by ICP‐OES. Basically, three main fractions namely protein, lipid and serum were separated. Organically bounded fraction was calculated from the sum of the element contents in protein and lipid fractions. The organically bounded fraction can be retained longer in the body than the other fractions, and its percentages of whole elements are between 3.8% and 92.2% in the samples. Additionally, the distribution tendency of each studied metal was variable, which is based on the sample characteristics and complexation reactivity of the metal. The organically bounded fraction for Fe, Cu, Zn and Mn is higher than the other elements in whole samples except whey powder. Investigated elements are basically included in ionic forms in whey powder. Additionally, Mg and Ca are usually observed as uncomplexed structures in the samples. 相似文献
167.
The decline of the European eel (Anguilla anguilla) stock has led the European Commission to enforce a regulation (Council Regulation N° 1100/2007), in which each member state was required to establish an eel management plan. Various measures in the French plan aim at restoring river connectivity by mitigating the impact of obstacles on the colonization of continental water by eels. Consequently, many obstacles are going to be equipped with elver ladder in the near future. In this context, a method to assess the passability of an obstacle seems essential. In this study, we developed a tag–recapture method, appropriate to glass eels and elvers, and an associated multi‐state mark–recapture model (i) to assess the passability of a ladder and (ii) to quantify the effect of various environmental factors on this passability. An application to a specific obstacle is applied as an illustrative example that demonstrates the relevance of the assessment method, and how the results can be used to propose technical solution to improve the efficiency of the ladder. Nine tag–recapture campaigns were carried on this obstacle, and about 4400 young eels were tagged. The model demonstrates that the efficiency of the ladder was rather low, especially during low river flow periods, mainly because of accessibility problems. The model also demonstrates the major influence of the river flow on the probability for an eel to pass the ladder; consequently, managing river flow during the migration period can be a relevant measure to improve river connectivity and facilitate colonization of the watershed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
168.
This study aimed to make an energy analysis of sugar beet production in K?rklareli Province of Turkey during production season in 2012–2013. In order to determine energy input-output of sugar beet, the surveys were performed in 48 sugar beet farms, selected by using Neyman method, located in K?rklareli Province. The data were collected by face-to-face questionnaires and observations. The energy input and output were calculated as 34,201.75 and as 285,600 MJ ha?1, respectively, in sugar beet production. Energy inputs consist of 41.97 % chemical fertilizer’s energy, 21.16 % diesel fuel energy, 11.97 % irrigation, 11.96 % electricity energy, 6.47 % human labour energy, 5.53 % machinery energy, 0.61 % seed energy and 0.33 % chemical energy. Energy usage efficiency, energy productivity, specific energy and net energy in sugar beet production were calculated as 8.35, 1.98 kg MJ?1, 0.50 MJ kg?1 and 251,398.25 MJ ha?1, respectively. 相似文献
169.
170.