虚拟同步发电机及其在多能互补微电网中的运行控制策略

针对西藏措勤县微网示范电站具有光伏、风电以及水电等在内的多能互补微网特性,研究并提出可以灵活实现微网组网的虚拟同步发电机(VSG)控制策略,讨论了多能互补微网系统各单元的组成及其控制,阐述了VSG的原理与系统建模,研究并分析了系统运行中光电站独立供电模式、光伏电站与水电站联合供电模式以及两种模式间的无缝切换策略,通过该微网的运行考核验证了所提控制策略的可行性与有效性。结果表明,所提的VSG控制策略具有较好的有功、无功均分性能;同时,还能很好地为系统提供惯性和阻尼,提升微网的供电质量与稳定运行能力;此外,还能满足微网不同运行模式之间的无缝切换。     

From demand response to integrateddemand response: review and prospect ofresearch and application

In the traditional power system demand response, customers respond to electricity price or incentive and change their original power consumption pattern accordingly to gain additional benefits. With the development of multienergy systems (MES) in which electricity, heat, natural gas and other forms of energy are coupled with each other, all types of energy customers are able to participate in demand response, leading to the concept of integrated demand response (IDR). In IDR, energy consumers can response not only by reducing energy consumption or opting for off-peak energy consumption but also by changing the type of the consumed energy. Taking the traditional demand response in power system as a starting point, the studies of the fundamental theory, framework design and potential estimation of demand response in power system are reviewed, and the practical cases and software development of demand response are introduced. Finally, the current theoretical research and application of IDR are assessed.     

梳棉机采用柔性梳理工艺提高成纱质量

采用实验分析的方法,研究在梳棉机上采用柔性梳理工艺提高成纱质量的问题。文章通过优选锡林刺辊速度,确定合理的锡林与活动盖板、刺辊与给棉板、锡林与道夫、锡林与前后固定盖板隔距等参数,选择配套合理性价比高的大白鲨针布等技术措施,使成纱质量有较大程度的改善。     

多能点γ准直标定源的建立及其应用

介绍了利用工业60Co线状源建立多能点γ准直标定源的方法。阐述了理论依据、大幅度降低散射本底的措施、理论计算方法、注量率实测方法、对安全防护和承重问题的考虑等，并对实验结果进行了讨论。     

DCS、PLC、状态监测仪实现大型

以乙烯厂聚乙烯装置C400压缩机的监控为例,介绍了状态监测仪、PLC和DCS的性能和特点,提出了基于以上三者的压缩机监控方案,并介绍了这套系统的优良性能.     

电热水器标准现状及发展趋势分析

本文对电热水器标准体系的发展情况及现状进行了梳理，对近几年电热水器标准制修订的重点进行了解析，并对电热水器标准未来的制修订方向提出了见解。     

Functional replacement of yeast flavocytochrome b2 with bacterial l-lactate dehydrogenase

Using yeast genetic complementation, we show here that Rhodobacter sphaeroidesl-lactate dehydrogenase can functionally replace flavocytochrome b₂ in Saccharomyces cerevisiae, only when a matrix-targeting signal of flavocytochrome b₂ is fused with the bacterial enzyme. The recombinant l-lactate dehydrogenase may add alternative route of mitochondrial electron transport other than flavocytochrome b₂.     

A Cautionary Note on the Use of Split-YFP/BiFC in Plant Protein-Protein Interaction Studies

Since its introduction in plants 10 years ago, the bimolecular fluorescence complementation (BiFC) method, or split-YFP (yellow fluorescent protein), has gained popularity within the plant biology field as a method to study protein-protein interactions. BiFC is based on the restoration of fluorescence after the two non-fluorescent halves of a fluorescent protein are brought together by a protein-protein interaction event. The major drawback of BiFC is that the fluorescent protein halves are prone to self-assembly independent of a protein-protein interaction event. To circumvent this problem, several modifications of the technique have been suggested, but these modifications have not lead to improvements in plant BiFC protocols. Therefore, it remains crucial to include appropriate internal controls. Our literature survey of recent BiFC studies in plants shows that most studies use inappropriate controls, and a qualitative rather than quantitative read-out of fluorescence. Therefore, we provide a cautionary note and beginner’s guideline for the setup of BiFC experiments, discussing each step of the protocol, including vector choice, plant expression systems, negative controls, and signal detection. In addition, we present our experience with BiFC with respect to self-assembly, peptide linkers, and incubation temperature. With this note, we aim to provide a guideline that will improve the quality of plant BiFC experiments.     

Molecular cloning of CaYRB1, the Candida albicans RanBP1/YRB1 homologue.

The yeast Ran binding protein 1 (Yrb1p) is a small protein of 23 kDa that is highly conserved among eukaryotes. It stimulates the GTPase activity of Gsp1p in the presence of the GTPase activating protein Rna1p. In addition to its role in nucleocytoplasmic transport of macromolecules, YRB1/RanBP1 could be involved in the regulation of microtubules structure and dynamics. Since microtubules are tightly associated with morphological changes, we have been interested to study the role and function of YRB1 in the pathogenic fungus Candida albicans, where there is regulated change in cellular morphology. The gene product of CaYRB1 encodes a 212 amino acid protein displaying 73% homology to the S. cerevisiae homologue. The bacterially expressed gene product has an apparent molecular weight of 35.7 kDa. We show that it can complement a S. cerevisiae yrb1 null mutant and that its mRNA does not appear to be regulated in response to conditions inducing morphological changes in C. albicans.     

Heating control schemes for energy management in buildings

Because of both the global energy crisis and the necessary improvement of energy efficiency in buildings, one of the largest sectors of energy consumption and greenhouse gases emissions, a strategy allowing managing energy resources is proposed. Its aim is reducing energy consumption and promoting the use of renewable energy, while ensuring thermal comfort, when heating “multi-energy” buildings, thanks to indoor temperature control schemes. Three schemes (based on a commonly used PID controller and on the combination of PID and model predictive or fuzzy controllers) were tested in simulation, using dynamic models describing the thermal behavior of a building, and fully met the management strategy's requirements, especially reducing the consumption of fossil energy. Three criteria describing the way energy is used and controlled in real-time were defined with the aim of evaluating the control schemes performance and adapting the strategy to the specific use of a building. The PID-MPC provided the best results while the PID-FLC proved to be a very good compromise, thanks to both the flexibility and the adaptability offered by fuzzy logic, between the easy-to-develop but not-very-efficient PID and the efficient but hard-to-develop PID-MPC.