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991.
992.
In the following, different techniques for a heat‐induced pretreatment of lignocellulosic biomass for the production of solid fuels are described. Thereby, also changes at the molecular level of the biomass are discussed. The discussed techniques (torrefaction, hydrothermal carbonization, vapothermal carbonization, and autoclaving) proceed in a temperature range up to 300 °C. Finally, a classification of the different techniques takes place to evaluate the specific advantages and disadvantages.  相似文献   
993.
The ELM coils in ITER are intended to provide control of Edge Localized Modes (ELMs). These coils are located on the outboard side of ITER between the shield modules and vacuum vessel (VV) and are subject to high radiation levels. Detailed three-dimensional (3-D) models of the toroidal and poloidal legs of the ELM coil and surrounding region for the MCNP code were updated to reflect the latest design changes. Neutronics calculations were performed to determine a variety of radiation damage parameters for the ELM coils as well as the VV located behind them. Additionally, detailed CAD based models for the upper ELM coil region were used to perform a CAD based analysis using the DAG-MCNP5 code. The results show that the ELM coil will meet the specified material radiation limits. However, the nuclear heating on the vacuum vessel behind the poloidal multi-pipe manifolds will exceed the specified limit.  相似文献   
994.
The regeneration of complex capital goods is afflicted with a high degree of uncertainty. Neither the extent of the damage to the goods nor the resulting maintenance workload is known in advance, and that poses challenges for capacity planning. Data fusion in the form of Bayesian networks is used to prepare forecasts in order to estimate the workload in maintenance processes. The objective is to optimize the planability of the capacities required.  相似文献   
995.
996.
We describe a novel methodology that examines perceptions of urban space, and present a study using this methodology that explores people’s perceptions of their neighbourhood. Previous studies of spatial cues have involved a variety of tasks such as pointing and sketching to externalise participants’ internal spatial maps. Our methodology extends these approaches by introducing mobile technologies alongside traditional materials and tasks. Participants use mobile phones to carry out self-guided neighbourhood tours. We collected rich qualitative data from 15 participants during two workshops and a self-directed neighbourhood tour. Our study highlights the use of public and private landmarks, differences in spatial maps of rural versus urban dwellers, and individual variance in orientation strategies. These themes suggest guidelines for the design of technologies with personalised spatial profiles.  相似文献   
997.
Business interests and agendas have been amongst the most influential drivers in the restructuring of the UK planning system over the past 30 years. Yet questions regarding the nature of business and business agendas and the power and influence of business interests have been somewhat under-developed in recent planning theory. In this paper we adopt a distinctive approach to theorizing business interest representation and business–state relations based on a strategic-relational approach. This seeks to establish an explicit focus on the dynamics of business–state relations, a standpoint of particular salience to planning and planning theory. It also offers distinctive theoretical perspectives regarding questions of business power and the evaluation of business influence, as well as informing contemporary debates around the engagement of business in planning processes. These insights hold significant potential in extending understanding of governance dynamics and the realities of planning politics and practice.  相似文献   
998.
Bernie Weir 《今日电子》2010,(10):40-41,45
过去几年来,高亮度发光二极管(HB-LED)在每封装流明输出和光效(单位为1 m/W)方面的性能快速提升。商用的1W LED已提供有冷色温LED(色温5000K)的每封装流明输出超过1001 m,光效达1001m/W,而相同功率等级的暖色温白光LED(色温3000~3500K)也超过了70~801 m。与两年前相比,这些性能等级提高了30%~40%。  相似文献   
999.

Object

Ultra-high field (UHF) neuroimaging is usually conducted with volume transmit (Tx) and phased array receive (Rx) coils, both tightly enclosing the object. The travelling-wave (TW) concept allows a remote excitation offering more flexible experimental setups. To investigate the feasibility of primate MRI in horizontal UHF MRI, we first compared the distribution of the electromagnetic fields in an oil phantom and then verified the concept with an in vivo experiment.

Materials and methods

In the phantom experiments an in-house circularly polarized hybrid birdcage coil and a self-developed patch antenna were used for Tx and an eight-element phased array antenna for Rx. B 1 + fields were calculated and measured for both approaches. For in vivo experiments the Rx part was replaced with an optimized three-element phased array head coil. The SAR was calculated using field simulation.

Results

In the phantom the field distribution was homogenous in a central volume of interest of about 10 cm diameter. The TW concept showed a slightly better homogeneity. Examination of a female crab-eating macaque led to homogeneous high-contrast images with a good delineation of anatomical details.

Conclusion

The TW concept opens up a new approach for MRI of medium-sized animals in horizontal UHF scanners.  相似文献   
1000.
The production of liquid hydrocarbons based on CO2 and renewable H2 is a multi‐step process consisting of water electrolysis, reverse water‐gas shift, and Fischer‐Tropsch synthesis (FTS). The syngas will then also contain CO2 and probably sometimes H2O, too. Therefore, the kinetics of FTS on a commercial cobalt catalyst was studied with syngas containing CO, CO2, H2, and H2O. The intrinsic kinetic parameters as well as the influence of pore diffusion (technical particles) were determined. CO2 and H2O showed only negligible or minor influence on the reaction rate. The intrinsic kinetic parameters of the rate of CO consumption were evaluated using a Langmuir‐Hinshelwood (LH) approach. The effectiveness factor describing diffusion limitations was calculated by two different Thiele moduli. The first one was derived by a simplified pseudo first‐order approach, the second one by the LH approach. Only the latter, more complex model is in good agreement with the experimental results.  相似文献   
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