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排序方式: 共有82条查询结果,搜索用时 15 毫秒
2.
本设计提出了一种基于CPLD的0.01S计时器的设计方案。应用高速集成电路以硬件描述语言VHDL语言描述,采用Altera公司的可编程逻辑器件(CPLD)EPM7064SL84实现的现代智能计时仪表,为广大用户提供了方便。系统具有可靠性高,便于功能扩展,成本低,易普及等优点。 相似文献
3.
APPLICATIONOFHMB-45MONOCLONALANTIBODYANDS100PROTEININTHEIMMUNOHISTOCHEMICALDIAGNOSISOFMELANOMALiuDanya(刘丹亚);SuBaoshan(苏宝山);Xu... 相似文献
4.
急性过度通气对颅内高压家犬S100B和C反应蛋白的影响 总被引:1,自引:0,他引:1
目的观察急性过度通气对颅内压增高犬脑功能的影响。方法16条急性硬膜外血肿家犬均分为4组。A组为对照组,机械通气维持PETCO2在35-45 mmHg。B、C和D组则采用过度通气,使PETCO2分别维持在28-35 mmHg、20-27 mmHg及20 mmHg以下各1 h,在术前(T1)、机械通气后2 h(T2)6、h(T3)、12 h(T4)、24 h(T5)和48 h(T6)分别测定S100B和C反应蛋白(CRP)含量。结果实验组S100B和CRP含量术后不同程度升高。D组S100B 6 h后升高,12 h达到峰值,24 h轻微下降,与术前及对照组比较差异显著(P<0.05),而CRP 2 h后增高,6 h达峰值且持续到48 h,与术前及对照组比较差异显著(P<0.05),B组、C组与对照组比较无差异。结论轻、中度过度通气对家犬脑功能影响较小,重度过度通气对硬膜外血肿犬可引起脑缺血。 相似文献
5.
国产微型汽车只带有3个前进挡和1个倒挡的变速器,因此在差速器驱动桥上增设了一个具有2个前进挡和1个直接挡的“动力储备变速箱”,使微车拥有6个前进挡,实现了微车驱动轮的输出转矩和速度的变化范围扩大,提高了整车的动力性和经济性. 相似文献
6.
Laurence C. Breaker David B. Gilhousen Hendrik L. Tolman Lawrence D. Burroughs 《Journal of Marine Systems》1998,16(3-4)
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
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8.
王剑博 《城市轨道交通研究》2021,24(2):30-33
100%低地板现代有轨电车具有节能、环保、投资小、载客量适中、乘坐舒适性高、后期维护费用低等特点,同时面临着严峻的轻量化及减重要求。对车体结构轻量化以及车体部件和内饰部件轻量化材料的应用开展研究,介绍了相关设计结构及应用方案。 相似文献
9.
利用S-100蛋白抗体对126例涎腺肿瘤(多形性腺瘤、恶性多形性腺瘤、粘液表皮样癌、腺样囊性癌、基底细胞腺瘤和乳头状囊腺瘤等)进行了免疫组化研究。结果发现:5种肿瘤中都有瘤细胞或部分瘤细胞表达S-100蛋白;但乳头状囊腺瘤的肿瘤性上皮则呈S-100蛋白阴性反应。提示:S-100蛋白抗原在涎腺肿瘤性肌上皮细胞中均有表达。 相似文献
10.
范晓云 《城市轨道交通研究》2015,18(7):129-132
100%低地板有轨电车的车底空间狭窄,复轨救援与常规轨道交通车辆有所不同。结合广州海珠区储能式100%低地板有轨电车的技术条件和相应复轨救援设备的特点,分析了100%低地板有轨电车头车出轨、中间车出轨,以及列车在曲线段出轨、转向架轴承卡死等各种出轨工况下的复轨救援模式。大部分工况下是可以使用复轨装置进行复轨操作的;在曲线段出轨时,可结合现场情况选择吊机复轨方式;中间车出现轮轴卡死时,在紧急情况下可采取必要的破坏性措施。 相似文献