557 resultados para Kraft pulping


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Studies conducted in the laboratory and field have shown that iced fish can be preserved for longer periods in fresh and edible condition in conventional bamboo baskets by providing additional insulated linings of double layer of gunny and polythene or bitumen coated kraft paper. The quality of fish is adjudged by chemical and organoleptic evaluations.

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The expression of the histo-blood group carbohydrate structures T-nouvelle (Tn, CD175), sialylated To (CD175s) and the Thomsen-Friedenreich disaccharide (TF, CD176) on human leukemia cell lines was analyzed by their reactivity with specific monoclonal ant

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An established Stochastic Reactor Model (SRM) is used to simulate the transition from Spark Ignition (SI) to Homogeneous Charge Compression Ignition (HCCI) combustion mode in a four cylinder in-line four-stroke naturally aspirated direct injection SI engine with cam profile switching. The SRM is coupled with GT-Power, a one-dimensional engine simulation tool used for modelling engine breathing during the open valve portion of the engine cycle, enabling multi-cycle simulations. The mode change is achieved by switching the cam profiles and phasing, resulting in a Negative Valve Overlap (NVO), opening the throttle, advancing the spark timing and reducing the fuel mass as well as using a pilot injection. A proven technique for tabulating the model is used to create look-up tables in both SI and HCCI modes. In HCCI mode several tables are required, including tables for the first NVO, transient valve timing NVO, transient valve timing HCCI and steady valve timing HCCI and NVO. This results in the ability to simulate the transition with detailed chemistry in very short computation times. The tables are then used to optimise the transition with the goal of reducing NO x emissions and fluctuations in IMEP. Copyright © 2010 SAE International.

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A Stochastic Reactor Model (SRM) has been used to simulate the transition from Spark Ignition (SI) mode to Homogeneous Charge Compression Ignition (HCCI) mode in a four cylinder in-line four-stroke naturally aspirated direct injection SI engine with cam profile switching. The SRM is coupled with GT-Power, a one-dimensional engine simulation tool used for modelling engine breathing during the open valve portion of the engine cycle, enabling multi-cycle simulations. The model is initially calibrated in both modes using steady state data from SI and HCCI operation. The mode change is achieved by switching the cam profiles and phasing, resulting in a Negative Valve Overlap (NVO), opening the throttle, advancing the spark timing and reducing the fuel mass as well as utilising a pilot injection. Experimental data is presented along with the simulation results. The model is used to investigate key control parameters and their effects on parameters that are difficult to measure experimentally. The effect of the spark in the first HCCI cycles is found to have a major impact on the stability of the transition. Copyright © 2010 SAE International.

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在栅扫描束流配送系统下,进行了重离子束对运动靶体进行适形照射的可行性实验研究.利用实时修正束流扫描参数的方法,使得束流追踪靶体在横向上的运动;在纵向上利用一个机械驱动的束流降能装置(称深度扫描器)迅速调节束流能量,使得重离子束高剂量的Bragg峰区落在运动靶体需治疗的断层之上.实验结果表明:栅扫描器主动补偿靶体横向运动及深度扫描器补偿靶体纵向运动是可行的.

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从理论上研究了在主动型栅扫描束流配送系统下,靶体运动对靶区剂量均匀性以及重离子治疗适形程度的影响.模拟计算了在实验测量得到的脉冲束流照射下,栅扫描系统引导束流对运动靶体实施照射后,靶体运动模式与靶区各等能量断层剂量分布均匀性的关系.由这些模拟计算结果,得到了一些针对运动靶体提高靶区剂量分布均匀性的策略.模拟计算提供了一种评估运动靶体上剂量分布的有效手段,其结果及内涵为今后该方向上的可行性实验研究奠定了坚实的基础.

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Within the framework of the pilot heavy-ion therapy facility at GSI equipped with an active beam delivery system of advanced raster scanning technique, a feasibility study on actively conformal heavy-ion irradiation to moving tumors has been experimentally conducted. Laterally, real-time corrections to the beam scanning parameters by the raster scanner, leading to an active beam tracing, compensate for the lateral motion of a target volume. Longitudinally, a mechanically driven wedge energy degrader (called depth scanner) is applied to adjust the beam energy so as to locate the high-dose Bragg peak of heavy ion beam to the slice under treatment for the moving target volume. It has been experimentally shown that compensations for lateral target motion by the raster scanner and longitudinal target shift by the depth scanner are feasible.

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Respiration-induced target motion is a major problem in intensity-modulated radiation therapy. Beam segments are delivered serially to form the total dose distribution. In the presence of motion, the spatial relation between dose deposition from different segments will be lost. Usually, this results in over-and underdosage. Besides such interplay effects between target motion and dynamic beam delivery as known from photon therapy, changes in internal density have an impact on delivered dose for intensity-modulated charged particle therapy. In this study, we have analysed interplay effects between raster scanned carbon ion beams and target motion. Furthermore, the potential of an online motion strategy was assessed in several simulations. An extended version of the clinical treatment planning software was used to calculate dose distributions to moving targets with and without motion compensation. For motion compensation, each individual ion pencil beam tracked the planned target position in the lateral aswell as longitudinal direction. Target translations and rotations, including changes in internal density, were simulated. Target motion simulating breathing resulted in severe degradation of delivered dose distributions. For example, for motion amplitudes of +/- 15 mm, only 47% of the target volume received 80% of the planned dose. Unpredictability of resulting dose distributions was demonstrated by varying motion parameters. On the other hand, motion compensation allowed for dose distributions for moving targets comparable to those for static targets. Even limited compensation precision (standard deviation similar to 2 mm), introduced to simulate possible limitations of real-time target tracking, resulted in less than 3% loss in dose homogeneity.

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Geoacoustic properties of the seabed have a controlling role in the propagation and reverberation of sound in shallow-water environments. Several techniques are available to quantify the important properties but are usually unable to adequately sample the region of interest. In this paper, we explore the potential for obtaining geotechnical properties from a process-based stratigraphic model. Grain-size predictions from the stratigraphic model are combined with two acoustic models to estimate sound speed with distance across the New Jersey continental shelf and with depth below the seabed. Model predictions are compared to two independent sets of data: 1) Surficial sound speeds obtained through direct measurement using in situ compressional wave probes, and 2) sound speed as a function of depth obtained through inversion of seabed reflection measurements. In water depths less than 100 m, the model predictions produce a trend of decreasing grain-size and sound speed with increasing water depth as similarly observed in the measured surficial data. In water depths between 100 and 130 m, the model predictions exhibit an increase in sound speed that was not observed in the measured surficial data. A closer comparison indicates that the grain-sizes predicted for the surficial sediments are generally too small producing sound speeds that are too slow. The predicted sound speeds also tend to be too slow for sediments 0.5-20 m below the seabed in water depths greater than 100 m. However, in water depths less than 100 m, the sound speeds between 0.5-20-m subbottom depth are generally too fast. There are several reasons for the discrepancies including the stratigraphic model was limited to two dimensions, the model was unable to simulate biologic processes responsible for the high sound-speed shell material common in the model area, and incomplete geological records necessary to accurately predict grain-size

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Das Augustinerchorherrenstift Bernried ist eine Gründung des 12. Jahrhunderts und beheimatete bis zur Säkularisation 1803 einen Augustinerchorherrenkonvent. Die Stiftung des Grafenpaares Otto und Adelheid von Valley gehörte zu den neuen geistlichen Niederlassungen, die im Zuge der Reformbewegung der Regularkanoniker fundiert wurden. Für die Region um Bernried am Starnberger See wirkte das Stift als gestalterische Kraft über sechs Jahrhunderte hinweg. Großen Aufschwung nahm das Stift erneut im 18. Jahrhundert, als herausragende Pröpste gerade die musikalische Entwicklung des Konventes förderten: einige Pröpste wirkten als Komponisten; von den Musikalien haben sich zahlreiche Handschriften und Instrumente erhalten. Nach dem bewährten Schema der Germania Sacra skizziert die Autorin Walburga Scherbaum kenntnisreich die Geschichte, die Verfassung, das geistige und religiöse Leben, die Besitzgeschichte und vor allem das Personal des Stiftes von seiner Gründung bis zur Aufhebung. Mit diesem Werk werden die Bemühungen der Germania Sacra um die geistlichen Institutionen im Alten Reich um eine weitere geistliche Niederlassung im bayerischen Raum neben Raitenhaslach (Germania Sacra N. F. 11), Dietramszell (Germania Sacra N. F. 24), Benediktbeuern (Germania Sacra N. F. 28) und Wessobrunn (Germania Sacra N. F. 39) bereichert.