火灾爆炸危险指数法在气分装置安全评价中的应用浅谈

从物质因素和工艺因素两个方面探讨了道化学火灾、爆炸危险指数法对某工厂气分装置和液化烃罐区进行安全评价的适用性,并对其进行了安全评价,得出其安全措施补偿前后的火灾、爆炸指数(F&EI)和危险暴露面积、危害系数、危险等级,实际可能财产损失等指数。评价结果表明安全预防措施可以有效降低气分装置和液化烃罐区的风险程度。     

基于主导变量阻尼控制的双馈风电场次同步振荡抑制

针对双馈风电场经串联电容补偿线路进行输电时,可能发生并网系统的次同步振荡问题.本文首先根据双馈风电场经串联电容补偿并网系统的数学模型建立系统小扰动方程,并通过特征值分析法得到双馈风电场次同步振荡的主导变量.然后,根据系统等效阻抗模型和转子侧控制结构图对主导变量参与次同步振荡的机理进行分析,提出在控制系统中设置由功率阻尼...     

Improving farm management by modeling the contamination of farm tank milk with butyric acid bacteria

Control of contamination of farm tank milk (FTM) with the spore-forming butyric acid bacteria (BAB) is important to prevent the late-blowing defect in semi-hard cheeses. The risk of late blowing can be decreased via control of the contamination level of FTM with BAB. A modeling approach was applied to identify an effective control strategy at the farm level. The simulation model developed was based on a translation of the contamination pathway into a chain of unit operations. Using various simulations, the effects of factors related to feed quality, feed management, cattlehouse hygiene, and milking practices on the contamination level of FTM were evaluated. Contamination level of silage was found to be the most important factor. When silage contains on average less than 3 log₁₀ BAB/g, a basic pretreatment of udder teats before milking (∼75% removal of attached spores) is sufficient to assure an FTM contamination level below 1 BAB/mL. When silage contains more than 5 log₁₀ BAB/g, it should not be fed, because it then becomes almost impossible to assure an FTM contamination level below 1 BAB/mL. Measures aimed at improving cattlehouse hygiene, the contamination via soil, and the contamination level of other feeds contribute only marginally to the control of the contamination of FTM with BAB. Application of the modeling methodology could be beneficial for the control of the contamination of FTM with other microorganisms such as Bacillus cereus.     

风电场微观选址及发电量预测的探讨

对风资源评估、选址地面情况和风机位置的排布等影响风电场微观选址的因素进行了分析.阐述了风电场发电量的预测方法,通过实例说明如何使用相关软件来预测风电场发电量,并根据预测结果对风电场微观选址注意事项进行了探讨.     

对风电场场址地质勘察技术问题的探讨

目前,风电场工程地质勘察的阶段不明确,深度不明确,导致在风电场可行性研究审查过程中出现对区域稳定性、阶段划分、各阶段应完成的主要任务、达到目的的分歧。为此,本文提出了风电场工程地质勘察和审查的建议。     

浅议风电场升压站35kV侧就地动态无功补偿装置

简单介绍了在风电场设计中35 kV母线侧动态无功补偿装置中常用的三种补偿装置,通过工程实践中的应用,罗列出各种补偿方式的接线与平面布置图,做出经济、技术方案的对比,总结出各类补偿装置的特性。     

并网风电场联络线线损分析

风电场在配电网末端并网、风电输送线路较长时,线路损耗非常严重。结合某风电场的运行方式分析了风电场联络线线损过高的原因,提出了降低线损的方案。以并入哈密电网的马莲泉风电场为算例,构建仿真模型,基于实际运行数据对比研究了降低线损方案,并从经济性、风电接纳能力两方面分析了方案的可行性。研究结果有助于制定合理的风电接入方案,提高含风电系统的经济效益。     

考虑风资源影响的风电场电压波动和闪变评估

风电并网后引起的电压波动和闪变水平可能超出国家有关标准,造成严重的电能质量问题,因此,在风电并网之前需对这两者进行评估。采用了一种新的评估方法。区别于国际电工标准(IEC61400-21)中电压波动与闪变的评估,此方法考虑了风电场的风资源情况对这2个指标的影响。对风电场在不同出力下由阵风引起系统的电压波动进行计算,并用IEC闪变仪计算短时间闪变值Pst。用所提方法和IEC标准对我国某一新建的风电场进行评估。结果表明,所提方法不仅能有效地进行电压波动与闪变评估,而且能更好地考虑风速变化对风电场带来的潜在影响。     

Immunotoxicological risk of mycotoxins for domestic animals

Mycotoxins are a group of structurally diverse fungal secondary metabolites that elicit a wide spectrum of toxicological effects. Of particular interest is the capacity of some mycotoxins to alter normal immune function when present in food at levels below observable overt toxicity. The sensitivity of the immune system to mycotoxin-induced immunosuppression arises from the vulnerability of the continually proliferating and differentiating cells that participate in immune-mediated activities and regulate the complex communication network between cellular and humoral components. Mycotoxin-induced immunosuppression may be manifested as depressed T- or B-lymphocyte activity, suppressed antibody production and impaired macrophage/neutrophil-effector functions. The immune system is primarily responsible for defence against invading organisms. Suppressed immune function by mycotoxins may eventually decrease resistance to infectious diseases, reactivate chronic infections and/or decrease vaccine and drug efficacy.     

风电场监控软件集成服务模型设计与应用

大型风电场中的风电机组和监控系统一般由多个厂商提供，相互兼容困难，难以进行统一维护与管理。遵循IEC 61400-25标准的信息模型、信息交换模型及对Web Services的映射方法，设计了基于Web Services的风电场监控软件集成服务模型，讨论了基于该模型的多个异构风电机组与服务端互联互通的问题，给出了风电机组标准服务接口的定义方法和安全通信机制。通过对该模型的工程实现与应用分析，论证了所做工作对风电机组的统一监控和集成管理等问题的解决具有现实意义与应用价值。