皇冠app体育 Chinasaerospaceinstituteforthefirsttimeenrolledforeignstudents,promptingaChineseexpertonowelcomeitsfirsteightforeignstudentsonMarch19,thefirsttimeChinahasadmittedforeignstudentsintheaerospacefield,thePeople,Belarus,Kazakhstan,studyandoraldefenseoftheirthesis,theywillreceiveaChinesemastersdegreeinaerospacescience,thereportsaid."Chinasaerospaceindustrytechnologyiscomprehensiveespeciallyitssatellitesfornavigation,communicationandmeteorology,afieldinwhichChinacanandwouldliketohelpothercountriescultivatetalent,"JiaoWeixin,aspacescienceprofessoratPekingUniversity,,thecollegecustomizedcoursesthatwouldfitindividualstudentsneeds,akistan,Nigeria,Venezuela,,theacademyhasalsoimproveditstrainingsystem,teachingadministrationandcomprehensivecapabilities,"TheenrollmentofforeignstudentsalsoprovedthatChinastechnologyinthefieldhasmadehugeprogressduringthepastyears,"Jiaosaid."ChinausedtoreceivehelpfromcountriessuchastheformerSovietUnionandnowisabletohelpothers,whichisalsogoodforChinainbuildingitsinternationalimage."ALongMarch-2DrocketwaslaunchedinFebruarycarryingthe730-,Chinawillsee36launchesoftheLongMarchrocketseries,withmissionstoformanetworkforthedomesticnavigationsatellites,theXinhuaNewsAgencyreported.

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　　地下燃气管道埋设的*小覆土厚度应符合如下要求：

　　1.埋设在车行道下时，不得小于0.8m ;

　　2.埋设在非车行道(或街坊)下时，不得小于 0.6m ;

　　3.埋设在庭院内时，不得小于0.3m;

　　4.埋设在水田下时，不得小于0.8m。

　　对于容易漏气、漏油、漏腐蚀性液体的部位，如法兰、阀门等，应在燃气管道上采取保护措施。煤气管道管径DN≥500mm中压管、天然气管道管径DN≥300mm的高中压干管上阀门的两侧宜设置放散管(孔);地下液态液化石油气管道分段阀门之间应设置放散阀，其放散管管口距地面距离不应小于2m，地上液态液化石油气管道两阀门之间的管段上应设置管道安全阀。

　　燃气管道所用钢管(除镀锌钢管外)在安装前应作防腐处理，其中架空钢管的外壁应涂环氧铁红等防锈漆两遍，埋地钢管外壁应按设计要求做外防腐。当设计无规定时，埋地钢管外防腐可采用环氧煤沥青或聚乙烯胶粘带，埋地镀锌钢管外壁及螺纹连接部位应做普通级防腐绝缘，螺纹连接部位的修补可用水柏油涂刷并包扎玻璃布作三油二布处理，或用环氧煤沥青涂刷并包扎玻璃布作二油一布处理。