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41.
饱和-非饱和非稳定渗流作用下岩质边坡稳定性分析   总被引:2,自引:0,他引:2  
对岩质边坡在水位下降时坡体内的饱和—非饱和非稳定渗流和坡体稳定性进行了分析,渗流分析采用有限元法,坡体稳定分析采用有限元强度折减法。以塑性区位移突变作为边坡失稳判据,此时折减系数值即为坡体安全系数。以十里铺水库为例,对库岸岩体边坡进行了分析,并得出在水库水位降落影响下边坡的稳定安全系数随降落时间的增长而增大的结论。  相似文献   
42.
电容器投切开关的动态响应时间是动态无功补偿装置的一个重要性能指标,对补偿的效果有很大影响。文中对基于固态继电器的电容投切开关的动态响应时间进行了理论分析,并通过实验证明其正确性,为无功补偿装置的选型提供参考,有实际应用意义。  相似文献   
43.
“Claus+SSR”技术在硫磺装置上的应用   总被引:1,自引:0,他引:1  
罗勤高 《辽宁化工》2009,38(7):475-480
九江分公司Ⅲ套硫磺装置采用中石化自主开发的“Claus+SSR”硫磺回收技术,装置开工初期负荷只有设计的50%,目前装置已连续正常运行两年半,硫磺收率99.95%以上、排放烟气S02浓度95mg/m^3、装置能耗2819.39MJ/t(1kg EO=41.868MJ),达到了装置设计水平,完全满足《大气污染物综合排放标准》GB16297—1996烟气SO2浓度≯960mg/m^3的要求。该技术具有操作简单、能耗物耗较低的特点,是一种成熟可靠的硫回收工艺技术。  相似文献   
44.
基于Prony算法的次同步谐振检测方法   总被引:1,自引:0,他引:1  
提出一种可实时检测次同步谐振SSR(sub-synchronous resonance)的方法。基于电气量测量的思想,采样瞬时电流作为检测量。首先对采样电流信号进行滤噪处理,接着利用Prony算法进行分析,辨识出次同步分量的幅值,观察其在连续时间段上的变化规律,进而判定次同步谐振发生与否。此外介绍了Prony算法具体的实现步骤、噪声的处理方法以及Prony算法用于次同步谐振检测的性能优势。最后在IEEE第一标准测试系统模型上进行仿真,试验结果证明了基于Prony算法的次同步谐振检测方法的有效性。  相似文献   
45.
应用静止无功补偿器抑制发电机次同步振荡的研究   总被引:1,自引:0,他引:1  
文章针对静止无功补偿器(SVC)在抑制次同步振荡(SSR)方面的应用进行研究,对串联补偿电路中次同步振荡的产生机理进行了分析,对SVC抑制SSR的基本工作原理、控制策略进行了总结。在IEEE次同步振荡第一基准测试模型的基础上,建立了SVC的真实时域仿真模型,通过时域仿真验证了SVC在抑制SSR方面的有效性。  相似文献   
46.
利用抗、感矮化病毒病的花生品种ICGV86699和远杂9102为亲本配制杂交组合,构建重组近交系群体(RIL),采用SSR技术和BSA分析方法,结合F6各个家系接种病毒后ELISA的鉴定结果,得到1个与花生矮化病毒病抗性连锁的分子标记XY38。此标记与抗性基因间的遗传距离为7.5cM,具有作为抗性育种辅助选择技术的潜力。  相似文献   
47.
The relationship between genetic diversity and phenotype in olive, instrumental to improve the efficacy of olive clonal selection, is still far from being fully understood. This work reports on a comparison made between plant SSR genetic data and quality of monovarietal olive oils. Nine monovarietal oils produced by selected genotypes were characterised under chemical and sensory profiles. Fatty acid compositions were determined to evaluate quantitative differences among oils; some fatty acids are actually highly correlated with the genetic matrix, and PCA of fatty acids composition explains 85.53% variability. Moreover some oils characterised by high levels of oleic acid appeared interesting from a nutritional standpoint. Organoleptic profiles evidenced differences especially for the attributes defined as “pleasant flavours”; oils obtained by different genetic matrices were characterised by different flavour intensities of tomato or artichoke, almond or aromatic herbs, correspondence analysis among sensory pleasant attributes and olive oil samples explaining 91.68% variability.  相似文献   
48.
利用过零式固态继电器实现功率调整的方法   总被引:1,自引:0,他引:1  
提出了一种基于微处理器和利用固态继电器实现交流功率连续调整的方法.文中给出了具体的硬件控制电路、软件算法及详尽的程序清单.该方法已成功的应用于蒸汽锅炉加热功率控制.  相似文献   
49.
Present article embodies the design and analysis of an octagonal shaped split ring resonator based multiband antenna fed at vertex for wireless applications with frequency‐band reconfigurable characteristics. The proposed antenna is printed on FR4 substrate with electrical dimension of 0.4884 λ × 0.4329 λ × 0.0178 λ (44 × 39 × 1.6 mm3), at lower frequency of 3.33 GHz. The antenna consists of SRR based vertex fed octagonal ring as the radiation element and switchable reclined L‐shaped slotted ground plane. Antenna achieves six bands for wireless standards viz: upper WLAN (5.0/5.8 GHz), lower WiMAX (3.3 GHz), super extended C‐band (6.6 GHz), middle X band (9.9 GHz—for space communication), and lower KU band (15.9 GHz—for satellite communication systems operating band). Stable radiation patterns are observed for the operating bands with low cross polarization. The proposed design achieves hexa band characteristics during switching ON state of PIN diode located at reclined L‐shaped slot in the ground plane. Experimental characteristic of antenna shows close agreement with those obtained by simulation of the proposed antenna.  相似文献   
50.
During the 1950s–1960s, the Merkys river basin, the largest protected area of Lithuania, underwent severe anthropogenic regulations. Within the Baltic States, the genetic diversity of Phalaris arundinacea populations is unknown and how they might be affected by anthropogenic activities such as river regulation. The objectives of this study were to compare molecular parameters (SSRs or microsatellite loci) within and among populations from natural river fragments with populations from regulated river parts. Study populations have greater genetic diversity within, rather than among, populations. The upstream portion of the Merkys basin populations had lower genetic diversity compared with further downstream. The mean number of polymorphic SSR loci was lower for populations from regulated parts of the river basin compared with natural ones. Main principle coordinate analysis revealed populations of regulated rivers at marginal positions. Bayesian clustering showed that current populations are admixtures of 3 distinct genetic groups, based on STRUCTURE analysis (K = 3 groupings) in geographic subdivisions of (a) downstream populations (Var?n?, Verseka, Upper Grūda, Lower Grūda, Upper Merkys, Lower Merkys), (b) upstream populations (Upper ?al?ia, Ber??, Lower ?al?ia, Visin?ia, Lower ?altyk??ia, Nedil?), and (c) the 2 regulated sites in the distinct geographic area of Taurupis and Upper ?altyk??ia. P. arundinacea in the Merkys river basin does not all belong to a single, random‐mating population encompassing its tributaries or among populations across its geographic scales. In several instances, river regulation might impair the genetic diversity of P. arundinacea populations.  相似文献   
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