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61.
赵铁领 《时代汽车》2021,(8):107-108
电磁汽车发动机是一款,利用永磁铁和电磁铁同磁极之间,相互排斥的原理,设计出来的一款全新理念的汽车发动机。  相似文献   
62.
采用格林函数退耦合方法研究了非对称周期性Anderson模型.结果表明,在相干区随杂化作用的增强体系有能隙产生,且能隙具有较强的温度依赖.体系的磁化率随温度非单调变化.上述结果与Kondo绝缘体的行为一致.  相似文献   
63.
磁链轨迹控制在机车辅助逆变电源中的应用   总被引:1,自引:0,他引:1  
从逆变器供电的电压空间矢量和磁链轨迹控制原理出发,充分利用80196KC单片机的特点,分析磁链轨迹控制在软件实现方法和过程;并给出了在应用系统中实测的电压波形和电流波形以及利用磁链轨迹控制的逆变器控制系统在机车辅助逆变电源上的运用情况。  相似文献   
64.
液化蒸气爆炸——火球对人体的伤害评价   总被引:3,自引:0,他引:3  
郭海鹏  李浩 《世界海运》2002,25(5):17-18
为了使操作及管理人员对液化蒸气爆炸所产生的火球对人体所造成的伤害有一个具体的评判标准,本文通过数学公式及计算,结合图表,将液化气体容量与伤害范围以及对人体的伤害程度联系起来。通过此评价方法,人们可以方便地了解到爆炸火球与人体伤害程度的关系,以求更好地避免人体伤亡。实验结果证明了该算法的有效性。  相似文献   
65.
Measurements of boundary layer moisture have been acquired from Rotronic MP-100 sensors deployed on two NDBC buoys in the northern Gulf of Mexico from June through November 1993. For one sensor, which was retrieved approximately 8 months after deployment, the post- and precalibrations agreed closely and fell well within WMO specifications for accuracy. The second sensor operated continuously from June 1993 to February 1997 (3.5 years). Buoy observations of relative humidity and supporting data were used to calculate specific humidity and the surface fluxes of latent and sensible heat. Specific humidities from the buoys were compared with observations of moisture obtained from nearby ship reports, and the correlations were generally high (0.7–0.9). Surface gravity wave spectra were also acquired. The time series of specific humidity and the other buoy parameters revealed three primary scales of variability, small (h), synoptic (days), and seasonal (months). The synoptic variability was clearly dominant and occurred primarily during September, October, and November. Most of the synoptic variability was due to frontal systems that dropped down into the Gulf of Mexico from the continental US followed by air masses which were cold and dry. Cross-correlation analyses of the buoy data indicated that: (1) the moisture field was highly coherent over distances of 800 km or more in the northern Gulf of Mexico; and (2) both specific humidity and air temperature served as tracers of the motion associated with propagating atmospheric disturbances. These correlation analyses also revealed that the prevailing weather systems generally entered the buoy domain from the South prior to September, but primarily from the North thereafter. Spectra of the various buoy parameters indicated strong diurnal and semidiurnal variability for barometric pressure and sea surface temperature (SST) and lesser variability for air temperature, wind speed and significant wave height. The surface fluxes of latent and sensible heat were dominated by the synoptic events which took place from September through November with the transfer of latent heat being primarily from the ocean to the atmosphere. Finally, an analysis of the surface wave observations from each buoy, which included calculations of wave age and estimates of surface roughness, indicate that major heat and moisture flux events coincide with periods of active wave growth, although the data were insufficient to identify any causal relationships.  相似文献   
66.
A mathematical model was used to simulate monthly responses of the Gulf of Mexico hypoxia to variations in climate and anthropogenic nutrient loading over a 45-year period. We examined six hypothetical future scenarios that are based on observed and projected changes in the Mississippi River discharge, Mississippi River nitrate concentrations, and ambient water temperatures. In particular, we investigated the implications of a 30% decrease in the Mississippi River nitrogen flux, which was recently proposed by the Mississippi River Watershed/Gulf of Mexico Hypoxia Task Force as a measure to reduce the size of the hypoxic zone. Model simulations suggest that the frequency of hypoxia in the northern Gulf of Mexico is highly sensitive to variations in riverine nitrate flux, but also to variations in freshwater discharge and ambient water temperatures. A 30% decrease in the Mississippi River nitrate flux, for example, would reduce the frequency of hypoxia by 37%. Nevertheless, a 20% increase the Mississippi River discharge, which may occur under some climate change scenarios, would produce an increase in the frequency of hypoxia of the same magnitude. Thus, if the potential climatic variations are taken into account, a 30% decrease in the nitrogen flux of the Mississippi River may not be sufficient to accomplish the proposed hypoxia management goal.  相似文献   
67.
提高双波峰焊机焊接质量的分析及方法   总被引:1,自引:0,他引:1  
吴蕴 《舰船电子工程》2005,25(3):126-130
主要叙述了有关双波峰焊机各技术参数对焊接质量的影响,对关键技术方面进行了相应的分析。分别从焊接前的质量控制、工艺材料及工艺参数等几个方面探讨了如何提高波峰焊质量的有效方法,围绕如何用好波峰焊机,充分发挥其内在的潜力,提出一些见解。  相似文献   
68.
为解决洋山港三期工程预制构件早期强度较低的问题,对抗氯盐硅酸盐水泥的配方进行改进,开发出早强型抗氯盐硅酸盐水泥。研究结果表明,应用该水泥配制的高性能混凝土均具有较高的早期强度和后期强度,混凝土的电通量较低。综合考虑高性能混凝土的工作性、强度和耐久性,早强型抗氯盐硅酸盐水泥的三氧化硫的含量宜控制在1.3% ̄2.2%。  相似文献   
69.
周耀忠 《中国修船》2006,19(5):29-31
文章首先通过引入半空间区域的格林函数,推导出船舶空间磁场分布的理论计算公式;然后,应用离散方法将双重积分转化为双重求和,得出了可用于船舶空间磁场工程计算的实际公式,具有实用价值。  相似文献   
70.
VALUEOFMOTOREVOKEDPOTENTIALSBYMAGNETICSTIMULATIONINDIAGNOSISOFLUMBOSACRALRADICULOPATHYYangZhe;ChenJunchang;ZhaoLongzhuWangKun...  相似文献   
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