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1.
1000kV交流线路长串绝缘子污秽特性的研究   总被引:1,自引:5,他引:1  
针对我国准备建设的1000 kV电压等级的交流输电线路用的长串绝缘子,按照真型布置进行人工污秽特性研究。其研究内容包括绝缘子串长与50%人工污秽工频耐受电压U50关系;普通型、双伞型绝缘子及异型串的污耐压特性;附盐密度SDD、附灰密度NSDD、上下表面不均匀积污比对污耐压特性的影响等。指出绝缘子串的U50与串长呈非线性趋势;按线性拟合所求取的U50较试验所求取的U50要高1.6%-10.2%;单片绝缘子污耐压随着海拔的增加而下降等。其研究结果对1000 kV交流输电线路工程造价、线路的可靠运行及污秽外绝缘的合理设计具有重要意义。  相似文献   
2.
本文介绍了新世纪有线、无线电视台在制作、传输、管理方面的数字化、网络化、智能化的一些方针、策略,并且对电视台的采、编、录、播一体化的信息综合管理进行了探讨。  相似文献   
3.
为消除低浓度矿井煤层气对煤层开采存在的安全隐患,提出了低浓度矿井煤层气硫化物脱氧新工艺。采用热重分析进行了脱氧剂和脱氧催化剂(自行研制的SDD催化剂)选择,在固定床反应器上进行了催化Na2S氧化研究,并用热重试选了CO还原Na2SO4反应的催化剂。研究结果表明:以Na2S为脱氧剂,SDD为脱氧催化剂,在温度180~380℃、原料气空速100~190 h-1的条件下进行脱氧,然后在600~630℃,以Fe2O3为催化剂对脱氧后生成的Na2SO4进行CO还原,生成的Na2S可循环使用。该脱氧方法操作简便、温度低,无杂质气混入,效果较好。  相似文献   
4.
Pantel R 《Ultramicroscopy》2011,111(11):1607-1618
In this paper, during dopant analysis of silicon devices, we have observed a phenomenon generally neglected in EDX analysis: the coherent Bremsstrahlung (CB). We discussed the reason why and came to the conclusion that the analytical TEM used for these experiments presents a configuration and performances, which makes this equipment very sensitive to the CB effect. This is due to large collection solid angle and high counting rate of the four silicon drift EDX detectors (SDD), a high brightness electron source providing large probe current and moreover a geometry favorable to on axis crystal observations. We analyzed silicon devices containing Si [110] and Si [100] crystal areas at different energies (80–120–200 keV). We also observed relaxed SiGe (27 and 40 at% of Ge). The CB effect, whose intensity is maximum near zone axis beam alignment, manifests as characteristic broad peaks present in the X-ray spectrum background. The peak energies are predicted by a simple formula deduced for the CB models found in the literature and that we present simply. We evaluate also the CB peak intensities and discuss the importance of this effect on the detection and quantification traces of impurities. The CB peaks also give information on the analyzed crystal structure (measurement of the periodicity along the zone axis) and allow, in every particular experiment or system, to determine the median take off angle of the EDX detectors.  相似文献   
5.
A new model of whey protein thermal inactivation has been combined with a CFD model developed for skim milk spray drying. Extensive evaporation and particle formation models were used to calculate particle moisture contents, temperatures and residence times. Calculated parameters were then used as input data for an experimentally developed quality model based on Williams-Landel-Ferry (WLF) equations for inactivation kinetics. The developed quality model was implemented into the CFD code and calculated in parallel to simulations of skim milk droplets evaporation based on the characteristic drying curve approach. The quality model and the simulation procedure were validated by comparison of protein activity levels obtained from the CFD with data obtained from differential scanning calorimetry (DSC) of milk powder samples collected during skim milk spray drying experiments. The simulations for different feed rates fit well with measurement results and show that the loss of whey protein activity is lower at higher feed rates, due to lower temperature fields in this case.  相似文献   
6.
针对前期SDD1型机车牵引主动齿轮陆续出现断齿的问题进行了分析和整改,并将这些整改措施应用到SDD8型机车牵引主动齿轮的设计上。通过参数的优化、材料的选取、热处理的控制和压装过盈量的确定,对SDD8型机车的牵引主动齿轮进行了重新设计,期望该齿轮能达到机车运用1个大修周期的要求。  相似文献   
7.
王晓  任聪 《内燃机车》2010,(3):13-16
SDD10型机车是资阳机车有限公司根据土耳其KARABUK钢铁公司的要求设计制造的准轨电传动内燃调车机车。详细介绍了机车的总体布置、性能参数、主要系统特点及试验运用情况。  相似文献   
8.
1 INTRODUCTIONNumerousinvestigationshaveshownthatthemechanicalactioncaneffectivelychangethestateofamaterial,catalyzesomechemicalreactions ,bringaboutsomechemicalconversionsandconsiderablyac celeratemultiphaseprocesses .However,thiskindofresearchwasmostly…  相似文献   
9.
出口苏丹机车的运用与改进   总被引:1,自引:0,他引:1  
SDD1重型内燃机车、SDD1A轻型内燃机车是南车资阳机车有限公司2005--2006年先后为苏丹铁路研制的两种干线货运机车。介绍了这两种机车的主要结构、实际运用情况及主要改进措施。  相似文献   
10.
The Ignalina NPP has a pressure suppression type of confinement, which is referred to as the accident localization system (ALS). The ALS prevents the release of the radioactive material from the NPP to the environment during a loss-of-coolant accident (LOCA). Ten water pools are located in the two ALS towers (five pools in each tower), which separate the dry well from the wet well. These water pools condense the accident-generated steam and prevent high overpressures in the compartments.The steam distribution device (SDD), with the vertical vent pipes (nozzles) that are inserted under the water of the condensing pools, connects the dry well and the wet well. In case of an accident, these components must be capable of withstanding the dynamic loads generated by a LOCA for successful pressure suppression function.This paper presents the transient analysis of the SDD and their connections to the vertical steam corridors following a LOCA. A thermo-hydraulic analysis of the SDD was performed using the state-of-the-art COCOSYS code to determine pressure and temperature histories resulting from a LOCA. The finite element code NEPTUNE was used to evaluate the structural integrity of the SDD and its supporting reinforced concrete wall. Results show that, although portions of the SDD undergo plastic response and the outside surface of the vertical steam corridor reinforced concrete wall cracks, the structural integrity of the SDD and wall are maintained during a LOCA.  相似文献   
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