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排序方式: 共有491条查询结果,搜索用时 15 毫秒
91.
Irene Schneider Frédéric Gerke Carolina Kinzel Wolfgang Müller Sandra Tertsch Martin Kuprian Anke Bockreis 《?sterreichische Wasser- und Abfallwirtschaft》2016,68(1-2):24-30
Organic waste, especially kitchen and canteen waste, is produced in large quantities and is subject to considerable fluctuations, both in terms of its composition and quantity, due in part to changing seasonal factors. Kitchen waste commonly undergoes biological and primarily anaerobic waste treatment (fermentation), producing both material (digestate, fertilizers and soil conditioners) and energy resources (biogas, electrical and thermal energy). The introduction of decentral collection and treatment systems promises to offer new solutions with regard to resource and energy storage, and with regard to compensating for the previously mentioned fluctuations. Within this study kitchen waste was initially pretreated and processed at laboratory scale. Subsequently, the influence of storage at 5, 20 and 30?°C for a period of 28 days was investigated. It was determined that, when stored, acidification and a corresponding drop in pH value promptly set in. The higher the temperature, the higher the level of acidification and the higher the concentration of organic acids became. In order to analyze the effects of storage on kitchen waste as an energy source, its biogas potential was measured in correlation with storage duration and temperature. Neither factor proved to have any significant influence on gas yield. Due to acidification, which can be seen as a chemical decomposition process, stored substrates produced up to 20?% higher gas yield compared to the original substrate. Accordingly, unavoidable kitchen and canteen waste can be considered valuable energy sources, which can contribute to efficient and needs-oriented energy production. 相似文献
92.
Zhong-Xin Chen Joost van der Eyden† Wouter Koot Rob van den Berg Jan van Mechelen Anke Derking 《Journal of the American Ceramic Society》1995,78(11):2993-3001
Homogeneous thin films of zinc titanate have been successfully prepared on Si(100) wafers by depositing a film of zinc and titanium oxides (ZnO-TiO2 ) by low-pressure metalorganic chemical vapor deposition (MOCVD), followed by an annealing treatment. The precursors used for the deposition were diethylzinc (DEZ), tetraisopropoxide titanium (TPT), and water. By performing the deposition at temperatures between 140 and 350C, the stoichiometry of the as-deposited films could be effectively controlled over Zn/Ti ratios between 0.5 and 2.5, which cover the composition of various zinc titanate phases identified in the literature. The as-deposited ZnO-TiO2 films are amorphous, and possess a fairly smooth surface. XPS and SIMS analysis showed that the composition of these films is uniform over the wafer as well as through the films bulk. An annealing treatment of the as-deposited films at high temperature 相似文献
93.
现阶段,卡尔曼滤波是信息融合领域中广泛使用的融合算法,它在线性高斯模型下能得到最优估计,但在非线性非高斯的模型下不能达到理想的效果.在这种情况下,非线性目标跟踪已被人们广泛重视.扩展卡尔曼滤波器(EKF)是将卡尔曼滤波器(KF)进行Taylor展开,算法简单,计算快捷,适用于非线性程度不强,高斯的环境下.不敏卡尔曼滤波(UKF)是先对状态向量的后验概率密度函数(PDF)进行近似化然后再在标准卡尔曼滤波框架下进行递推滤波.粒子滤波是一种基于蒙特卡罗模拟和递推贝叶斯估计的滤波方法.这种滤波的方法和其他滤波的方法一样,都是可以通过系统的模型方程从测量空间一步步递推得到其相应的状态空间.它可以处理模型方程为非线性、噪声分布为非高斯分布的问题,在许多领域得到了成功的应用.论文中通过仿真试验,进行跟踪性能的比较,结果证明在复杂的非高斯非线性环境中,粒子滤波器的性能要明显优于扩展卡尔曼滤波器. 相似文献
94.
This paper presents a new design method of model predictive control (MPC) based on extended non-minimal state space models, in which the measured input and output variables, their past values together with the defined output errors are chosen as the state variables. It shows that this approach does not need the design of an observer to access the state information any more and by augmenting the process model and its objective function to include the changes of the system state variables, the control performances are superior to those of the controller that does not bear this feature. Furthermore, closed-loop transfer function representation of the model predictive control system facilitates the use of frequency response analysis methods for the nominal control performances of the system. 相似文献
95.
F Wu A Gericke CR Flach TR Mealy BA Seaton R Mendelsohn 《Canadian Metallurgical Quarterly》1998,74(6):3273-3281
Annexins comprise a family of proteins that exhibit a Ca2+-dependent binding to phospholipid membranes that is possibly relevant to their in vivo function. Although substantial structural information about the ternary (protein/lipid/Ca2+) interaction in bulk phases has been derived from a variety of techniques, little is known about the temporal and spatial organization of ternary monolayer films. The effect of Ca2+ on the interactions between annexin V (AxV) and anionic DMPA monolayers was therefore investigated using three complementary approaches: surface pressure measurements, infrared reflection-absorption spectroscopy (IRRAS), and Brewster angle microscopy (BAM). In the absence of Ca2+, the injection of AxV into an aqueous subphase beneath a DMPA monolayer initially in a liquid expanded phase produced BAM images revealing domains of protein presumably surrounded by liquid-expanded lipid. The protein-rich areas expanded with time, resulting in reduction of the area available to the DMPA and, eventually, in the formation of condensed lipid domains in spatial regions separate from the protein film. There was thus no evidence for a specific binary AxV/lipid interaction. In contrast, injection of AxV/Ca2+ at a total Ca2+ concentration of 10 microM beneath a DMPA monolayer revealed no pure protein domains, but rather the slow formation of pinhead structures. This was followed by slow (>2 h) rigidification of the whole film accompanied by an increase in surface pressure, and connection of solid domains to form a structure resembling strings of pearls. These changes were characteristic of this specific ternary interaction. Acyl chain conformational order of the DMPA, as measured by nu(sym)CH2 near 2850 cm(-1), was increased in both the AxV/DMPA and AxV/DMPA/Ca2+ monolayers compared to either DMPA monolayers alone or in the presence of Ca2+. The utility of the combined structural and temporal information derived from these three complementary techniques for the study of monolayers in situ at the air/water interface is evident from this work. 相似文献
96.
97.
Boris Eisenbart Kilian Gericke Lucienne T. M. Blessing 《Research in Engineering Design》2017,28(3):299-331
Interdisciplinary system development requires the integration of diverse expertise to combine different engineering technologies and—increasingly often—services, in order to provide users with expected value and desired functionality in newly developed products. Failure to achieve integration of disciplines can result in design errors posing a direct threat to the users and to the company. Function modelling is expected to provide suitable means for the integration of disciplines early in the development process. However, a plethora of function models can be found within different disciplines or even across, and their divergence has proven to hamper shared, cross-disciplinary function modelling in design teams. This article presents research on function modelling in different disciplines in practice. Conducted research comprises empirical studies in ten companies developing mechatronic systems and/or Product-Service Systems in diverse market areas. The studies provide insights into the utilisation of different function models in different disciplines and across, as well as the specific needs and preferences of practicing designers regarding interdisciplinary function modelling. Finally, the obtained insights and their implications for supporting interdisciplinary function modelling are being discussed. Indications are derived which may guide future research endeavours pertaining to the development of support for collaborative, (cross-)disciplinary function modelling. 相似文献
98.
99.
Intrusive reexperiencing in posttraumatic stress disorder (PTSD) has been linked to perceptual priming for trauma-related material. A prospective longitudinal study (N = 69) investigated perceptual priming for trauma-related, general threat, and neutral words in assault survivors with and without PTSD, using a new version of the word-stem completion task. Survivors with PTSD showed enhanced priming for trauma-related words. Furthermore, priming for trauma-related words measured soon after the trauma was associated with subsequent PTSD severity at 3, 6, and 9 months. The enhanced priming effect was specific to trauma-related words. Enhanced perceptual priming for traumatic material appears to be one of the cognitive processes operating in PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
We have achieved the covalent functionalisation of detonation nanodiamond by an esterification reaction of carboxylic acid chlorides on hydroxylated nanodiamond. The resulting “nanodiamond esters” with a surface loading of 0.3–0.4 mmol g− 1 of alkyl groups have been characterized by FTIR spectroscopy, thermogravimetry and elemental analysis. They exhibit a significantly improved dispersibility in organic solvents such as tetrahydrofurane and dichloromethane. 相似文献