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71.
Advanced biogas power generation technology has been attracting attentions, which contributes to the waste disposal and the mitigation of greenhouse gas emissions. This work proposes and models a novel biogas-fed hybrid power generation system consisting of solid oxide fuel cell, water gas shift reaction, thermal swing adsorption and proton exchange membrane fuel cell (SOFC-WGS-TSA-PEMFC). The thermodynamic, exergetic, and thermo-economic analyses of this hybrid system for power generation were conducted to comprehensively evaluate its performance. It was found that the novel biogas-fed hybrid system has a gross energy conversion efficiency of 68.63% and exergy efficiency of 65.36%, indicating high efficiency for this kind of hybrid power technology. The market sensitivity analysis showed that the hybrid system also has a low sensitivity to market price fluctuation. Under the current subsidy level for the distributed biogas power plant, the levelized cost of energy can be lowered to 0.02942 $/kWh for a 1 MW scale system. Accordingly, the payback period and annual return on investment can reach 1.4 year and about 20%, respectively. These results reveal that the proposed hybrid system is promising and economically feasible as a distributed power plant, especially for the small power scale (no more than 2 MW).  相似文献   
72.
为研究沿海台风中的风生飞射物对核电厂电气设备的冲击破坏,以核电厂户外高压电气设备的陶瓷绝缘材料为研究对象,基于LS-DYNA和HyperMesh,分析陶瓷部件在小球和钢管打击下的破坏情况。结果表明:在受到钢管垂直打击时,陶瓷部件很容易发生破坏;在受到小球冲击时,陶瓷部件局部表面发生破坏。进一步计算得到小球对陶瓷部件的临界破坏冲击速度,可为后续设计和研究提供参考。  相似文献   
73.
针对高速率通信网络和Round-Robin(RR)协议影响下网络化时变系统的有限时域[H∞]控制问题,考虑到系统中存在乘性噪声、随机时滞和量化效应,提出了一种基于观测器的有限时域[H∞]控制器的设计方法。利用李雅普诺夫稳定性理论和线性矩阵不等式(Linear Matrix Inequality,LMI)技术得到有限时域[H∞]控制器存在的充分条件。基于锥补线性化(Cone Complementarity Linearization,CCL)方法通过求解一组递归矩阵不等式得到观测器和控制器参数。所设计的控制器保证闭环网络化时变系统在给定的时域内稳定,且满足预定的[H∞]性能指标。数值仿真验证了所提方法的有效性。  相似文献   
74.
文中提出了一种利用有限数量的相量测量单元(PMU)和相量数据集中器(PDC)设计最优监控结构的方法。通过在大量的设定值场景下,使电力系统可观测性曲线的期望值最大化,同时使通信基础设施成本最小化,最终确定PMU和PDC的最佳位置。提出了一种非线性动态扩展卡尔曼滤波(EFK)状态观测器。这种状态观测器可以将暂态行为转换为由代数微分方程描述的广域电力系统,而无需非线性反演技术。最后以IEEE-5电力系统为例,说明了该方法的有效性。  相似文献   
75.
This paper introduces a thick 690 nickel-based alloy plate produced by the former Baosteel Special Steel Co.,Ltd.used as the steam-generator divider plate in the pressurized water reactor nuclear power plant.According to the product characteristics and design requirements of the thick nickel-based alloy plate, multidimensional sampling and testing were conducted to investigate its microstructure and mechanical properties.The results show that all the property indexes of the thick hot-rolled nickel-based alloy plate meet the design requirements, and there is good uniformity in the microstructure and mechanical properties in different dimensions.These findings indicate that China has mastered the core manufacturing technology of thick nickel-based alloy plates for their use as divider plates in nuclear power steam generators.  相似文献   
76.
Understanding energy transport in metal halide perovskites is essential to effectively guide further optimization of materials and device designs. However, difficulties to disentangle charge carrier diffusion, photon recycling, and photon transport have led to contradicting reports and uncertainty regarding which mechanism dominates. In this study, monocrystalline CsPbBr3 nanowires serve as 1D model systems to help unravel the respective contribution of energy transport processes in metal-halide perovskites. Spatially, temporally, and spectrally resolved photoluminescence (PL) microscopy reveals characteristic signatures of each transport mechanism from which a robust model describing the PL signal accounting for carrier diffusion, photon propagation, and photon recycling is developed. For the investigated CsPbBr3 nanowires, an ambipolar carrier mobility of μ = 35 cm2 V−1 s−1 is determined, and is found that charge carrier diffusion dominates the energy transport process over photon recycling. Moreover, the general applicability of the developed model is demonstrated on different perovskite compounds by applying it to data provided in previous related reports, from which clarity is gained as to why conflicting reports exist. These findings, therefore, serve as a useful tool to assist future studies aimed at characterizing energy transport mechanisms in semiconductor nanowires using PL.  相似文献   
77.
纳米药物非临床药代动力学的研究策略及关注要点   总被引:1,自引:0,他引:1  
随着纳米技术的迅速发展,纳米药物的研发已成为目前药物创新的发展方向之一。纳米药物具有基于纳米结构的尺度效应,其药代动力学特征与普通药物相比存在明显差异,其药代动力学研究与普通药物相比也有其特殊性。本文着重探讨纳米药物的非临床药代动力学的研究策略及关注要点,包括受试物、体内/外试验、生物样本分析、数据评价分析等,期望为研发者提供参考。  相似文献   
78.
With the development of intelligent manufacturing (IM), the Digital twin (DT) has become an important means to the evolution mechanism of the process. Many researchers pay attention on the realization of DT in different industries. Based on the DT and Digital Twin Shop Floor (DTS) model, a novel, high throughput metrology method is proposed in the process quality monitoring and control of the Series Solar Cell Production Line (SSCPL) for detailed performance analysis. The variance of individual loss parameters and their impact on quality performance are quantified and mapped into the virtual space. The nature of their distributions and correlations provide great insights about quality loss mechanisms in process monitoring, helping to prioritize efforts for optimizing the control of the SSCPL in the physical space. Additionally, the parameters can be tied back to the physical space, allowing the data to be used directly for the control in the manufacturing. The data-loop of “Autonomous perception of process parameters - Dynamic behaver mapping - Online monitoring - Online data analysis - Parameters configuration & control” can be obtained in the model. This paper provides an application paradigm for DT and IM.  相似文献   
79.
The fashionable Parr–Pearson (PP) atoms-in-molecule/bonding (AIM/AIB) approach for determining the exchanged charge necessary for acquiring an equalized electronegativity within a chemical bond is refined and generalized here by introducing the concepts of chemical power within the chemical orthogonal space (COS) in terms of electronegativity and chemical hardness. Electronegativity and chemical hardness are conceptually orthogonal, since there are opposite tendencies in bonding, i.e., reactivity vs. stability or the HOMO-LUMO middy level vs. the HOMO-LUMO interval (gap). Thus, atoms-in-molecule/bond electronegativity and chemical hardness are provided for in orthogonal space (COS), along with a generalized analytical expression of the exchanged electrons in bonding. Moreover, the present formalism surpasses the earlier Parr–Pearson limitation to the context of hetero-bonding molecules so as to also include the important case of covalent homo-bonding. The connections of the present COS analysis with PP formalism is analytically revealed, while a numerical illustration regarding the patterning and fragmentation of chemical benchmarking bondings is also presented and fundamental open questions are critically discussed.  相似文献   
80.
杨旻  李光 《包装工程》2021,42(9):221-229
目的为了解决柑橘在实际包装过程中因于人工手动装袋、装箱等导致的效率低下问题,设计一条全自动柑橘包装生产线。方法基于“不知火”柑橘的特殊体型特征,使用传送带分级装置对其进行分级;通过倾斜皮带解决柑橘排列姿态的整理问题;经给袋式包装机装袋后,采用扭结式扎口装置对其进行封口;利用并联机器人对其进行装箱。通过计算生产节拍,合理规划每个工序的循环时间,并通过Flexsim软件对该生产线进行仿真分析与平衡优化。结果该生产线整体效率由89%提升到93%,能够正常运行且满足生产力的需求。结论该柑橘包装生产线实现了柑橘的分级、整料、装袋、装箱等工序,降低了工作强度,提高了生产效率,实现了包装过程的自动化。  相似文献   
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