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991.
Özden Öztürk Ali Topal Fikret Akınerdem Necdet Akgün 《Journal of the science of food and agriculture》2008,88(1):141-150
BACKGROUND: Cereals are the main crops in rotation following sugar beet harvest. However, a delay in planting winter cereals as a result of late sugar beet harvest is a disadvantage in sugar beet/cereal rotations. In this study, field trials were carried out to investigate the effects of sowing and harvesting dates on the yield and quality of sugar beet (Beta vulgaris L.) and cereals (wheat, Triticum aestivum L., and six‐rowed barley, Hordeum vulgare L.) during two consecutive years. Beet was sown on three dates and harvested on four dates, followed by cereals which were sown on four dates. Root yield and digestion ratio (sugar beet) and grain yield, 1000‐kernel weight, test weight and protein content (wheat and barley) were determined. RESULTS: The highest root yield (52.53 t ha?1) was obtained from early sown (5 April) and late harvested (1 November) beet, while the highest digestion ratio (17.4%) was obtained from late sown (3 May) and late harvested (1 November) beet. Lower cereal grain yields were obtained from later sowings. The highest grain yields (5.87 and 6.02 t ha?1) were obtained from earlier sown wheat. Protein content was also affected by sowing date, which appeared to be very important under unstable climatic conditions. CONCLUSION: It is essential to consider the timing of sowing of cereal crops when unstable climatic conditions are present. Hence sowing date recommendations in regular climatic conditions may be misleading for countries dependent on winter rainfall for cereal production. Copyright © 2007 Society of Chemical Industry 相似文献
992.
Ali Kemal Şehirlioğlu Cenk Özler 《The International Journal of Advanced Manufacturing Technology》2008,35(7-8):769-777
The response surface methodology (RSM) approach can be used to determine the optimal component tolerances in an assembly.
Frequently, response surface designs such as Box-Behnken design and central composite design are used in tolerance allocation
problems. In this article, mixture experiments, which are essentially constructed for designing a blend composition, are proposed
instead of response surface designs in order to observe the cost values. Also some advantages and disadvantages of mixture
designs are discussed. 相似文献
993.
P. W. Neumann W. Sutthoff Max Müller M. Pleißner G. Sonntag C. A. Neufeld E. Dinslage J. Clement P. Buttenberg und M. Schütz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1910,19(11):660-677
Ohne Zusammenfassung 相似文献
994.
Robert Westlund Eva Malmström Cesar Lopes Johan Öhgren Thomas Rodgers Yuika Saito Satoshi Kawata Eirik Glimsdal Mikael Lindgren 《Advanced functional materials》2008,18(13):1939-1948
Platinum(II) acetylides were incorporated into poly(methyl methacrylate) (PMMA) glasses to obtain solid‐state nonlinear optical devices. We report on device fabrication, structural, chemical, and mechanical properties, as well as the optical limiting capabilities of the final solids. Two different guest‐host systems are presented: 1) Dye molecules functionalized to be readily dispersed in methyl methacrylate (MMA) and subsequent in situ polymerization of the MMA yielding solid PMMA host matrices. 2) Dye molecules functionalized to copolymerize with MMA forming covalent bonds between the guest and the PMMA host matrix. A range of doped organic solids were prepared, reaching concentrations up to 13 wt% of the guest molecule. Raman spectra of the doped solid devices indicate that the chemical structure of the nonlinear dyes remains intact upon the polymerization of the solid matrix. Luminescence spectra confirm that the basic photophysical properties observed for the same solute molecules in THF are maintained also in the solid state. Optical power limiting (OPL) characterization reveal clamping levels for the dyes nonbonded to the solid host being less than 4 µJ at pulse energies up to 110 µJ at 532 nm (f/5 arrangement and 5 ns pulses), which is comparable to the performance of similar dyes in THF solutions. In contrast, the highly crosslinked solid possesses a higher clamping level (8 µJ) at the same nominal concentration. 相似文献
995.
996.
M. Duran Toksarı Ertan Güner 《The International Journal of Advanced Manufacturing Technology》2008,38(7-8):801-808
In this study, we introduce a mixed nonlinear integer programming formulation for parallel machine earliness/tardiness (ET) scheduling with simultaneous effects of learning and linear deterioration, sequence-dependent setups, and a common due-date for all jobs. By the effects of learning and linear deterioration, we propose that the processing time of a job is defined by increasing function of its execution start time and position in the sequence. The developed model allows sequence-dependent setups and sequence-dependent early/tardy penalties. The model can easily provide the optimal solution to problems involving about eleven jobs and two machines. 相似文献
997.
M. Pleißner und M. Schütz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1910,20(8):526-527
Ohne Zusammenfassung 相似文献
998.
Oxidative steam reforming of propane was tested over four Pt–Ni/δ-Al2O3 bimetallic catalysts aiming to investigate the effect of metal loadings and Ni:Pt loading ratio on catalyst performance. A trimetallic Pt–Ni–Au/δ-Al2O3 catalyst was additionally studied aiming to understand the effect of Au presence. Reaction temperature, carbon to oxygen ratio, and residence time were taken as the reaction parameters. The effect of C/O2 ratio on the hydrogen production and H2/CO selectivity was found dependent on the Pt and Ni loadings. The results underlined the importance of C/O2 ratio as an optimization parameter for product distribution. The highest hydrogen production and H2/CO ratio levels were obtained for the highest C/O2 ratio tested. An optimum Ni:Pt weight ratio was found around 50 due to suppressed methanation and enhanced hydrogen production activities of these catalysts. The presence of gold in the trimetallic catalyst caused poor activity and selectivity in comparison to bimetallic catalysts. 相似文献
999.
1000.
Ergüven Vatandas İbrahim Özkol 《International journal for numerical methods in engineering》2008,74(12):1771-1794
In this study, Onera M6 wing has been optimized by two parameters, the wing section and the taper ratio, by combining the recent mostly preferable popular approaches, i.e. parallel computing and evolutionary techniques. For the 3‐D models, developed during the optimization stages, the mesh required has been generated by using dynamic mesh technique. The code developed for this is robust and faster than the codes that produce mesh only by classical techniques. An Euler flow solver (ACER3D) is used to obtain the flow parameters for each member. From the results, it is observed that the optimization process is working as expected. During the optimization process, the lift coefficient and the thickness ratio are tried to be maintained close to the design values determined at the beginning. The taper ratio becomes smaller and converges to a certain value, while the code tries to minimize the drag force. Additionally, this study can be used as a reference for 2‐D or 3‐D aerodynamic body optimization by using heuristic‐type algorithms, since all details are outlined, referenced, and interpreted with their advantages and disadvantages. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献