grade n. 1.等级,级别;阶段;程度,标准,水平。 2.〔美国〕(中小学的)年级;某一年级的学生。 3.〔pl.〕 〔美国〕小学校 (=grade school). 4.(学校考试的)评分等级。 5.〔主美〕坡度,斜坡,倾斜度。 6.【畜牧】改良杂种。 7.【语言学】母音交替。 a poor grade of tea 低级茶。 grade A eggs 甲级鸡蛋。 teach in the grades 做小学教师。 at grade 〔美国〕在同一水准面上。 make the grade 1. 上陡坡。 2. 达到标准;成功。 on the down grade 走下坡路,在衰败中。 on the up grade 走上坡路,在兴盛中。 up to grade 合格。 vt. 1.定…的次序,定…的等级,给…分类,给…分级。 2.〔美国〕减缓(坡度);【地质学;地理学】均夷;使(色调)渐浓[渐淡]。 3.给…记分数。 4.【畜牧】通过杂交改良 (up)。 vi. 1.属某种等级。 2.(颜色等)渐次调和[变化]。
According to the types , height and fireproof grade of the buildings , four basic ringed arrangements are brought up , namely the ringed arrangemensts of branch lines , the ringed arrangements of cross mains , the ringed arrangements of feed mains and the ringed arrangements of fire waterhead . on the basis of analyzing the means , characteristic and applicability of the four basic ringed arrangements , several practicality ringed arrangements are brought up , namely the ringed arrangements of branch lines and cross mains , the ringed arrangements of cross mains and feed mains , the ringed arrangements of branch lines and feed mains , the vertical ringed arrangements of feed mains and the ringed arrangements of sprinkler system in the abnormity buildings 根据建筑物的类型、高度和防火等级等因素,提出配水支管环状、配水干管环状、立管环状和消防水源环状这四种基本环状形式,分析了四种环状管网的环状布置方法、特点和适用性。在此基础上又提出了支管与干管环状、干管与立管环状、支管与立管环状、立管竖向环状以及不规则区域环状等几种实用的环状形式。