学科分类
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9 个结果
  • 简介:OnNovember18,2001,thesecondphasecofferdamofThreeGorgesProjectwasstartedtodismantle.Thedismantlementofcofferdamwithheightof80oddm,weircrestwidthof15mandoveralllengthof2.4km,marksthebeginningofthesecondtimecutoffofThreeGorgesProject—thecutoffofdiversion

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  • 简介:Thispaperpresentsauniquenoveldesignofthephase-shiftedcascadehighvoltageinverter.Thehighvoltageinverterutilizesfewerpowerswitchesandsuppliesabalanceload.TheusageofphaseshifttransformerandphaseshiftingSPWMensuresthatinputandoutputharmonicwavecontentislowandoutputvoltagechange(du/dt)hasalowrate,meetingalltherequirementsofthepowerauthorities.Themostout-standingfeatureistheenergysavingwithveryfastcostrecovery.

  • 标签: 高压反相器 相移位级联 多级SPWM 功率开关
  • 简介:摘要本文提出了一种相移掩模(PSM)在国产清洗机PMC1500上清洗时phase掉落幅度控制的方法。在相移掩模制备过程中,影响phase值大小的因素较多,干法蚀刻的时间,清洗工艺等对相移掩模的phase值都有很大的影响。177°—183°的phase大小,是PSM版在晶圆工厂使用的常规要求,研究中提出了对相移掩模清洗phase值掉落的控制,在保证清洗能力的情况下,通过对清洗过程中影响phase值掉落的重要因素进行改良,清洗流程包中包含SPM清洗以及SC1清洗的工艺,通过逐一改变SPM以及SC1的清洗条件,实现对PSM掩模phase值掉落的控制研究,最终确定了SC1清洗工艺时间对PSM掩模phase掉落的影响较大,通过控制SC1的清洗工艺方式,有效地控制PSM掩模清洗时phase值的掉落。

  • 标签: 相移掩模 PMC1500 phase SPM SC1
  • 简介:ChinaandCanadahavesignedaprojectawardagreementfortheco-operationfortheQinshanPhaseⅢCandunuclearpowerproject,markingsignificantprogressincommercialnegotiationsbetweenbothcountriesontheconstructionoftwo700megawattclassCanduunits.Theagreement,signedbetweentheChinaNationalNuclearCorp(CNNC)andtheAtomicEnergyofCanadaLtd(AECL)inBeijingonJuly12,finalizedthepriceandcommercialtermsforQinshanPhaseⅢ

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  • 简介:OnOctober15,2001,No.7generatingunitofYunnanXuanweiPowerGenerationCorp.5thphaseprojectwassuccessfullyputintooperationandconnectedtothepowernetwork.Hitherto,XuanweiPowerPlant5thphaseextensionprojectwaswhollycompleted.XuanweiPowerPlant5thphaseextensionprojectis

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