排序方式: 共有102条查询结果,搜索用时 15 毫秒
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扁壶,又称扁瓶,主体呈扁圆或扁方形壶腹,两侧有桥形或半圆形系,底部方形或椭圆形,圈足侧而各有一孔,因其可穿绳背挂,故又叫做穿带壶(或穿带瓶)。该器型最早出现于新石器时代,为陶器,西晋时始有瓷制器。辽、宋、金、西夏时期北方少数民族地区最为流行,适于游牧、行旅中作酒壶或水壶用,多为黑釉、黄釉、褐釉及白釉印花器(图1)。 相似文献
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热力管道方形热补偿器的制作安装技术 总被引:1,自引:0,他引:1
文章系统分析了热力管道热膨胀情况和介绍常用方形补偿器的制作与安装技术. 相似文献
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工厂对大批量生产方形曲面槽,在工艺上零件加工长度超过X62铣床纵向行程长度,拟采用的办法是在C620普通车床的基础上,根据铣削的原理、特点,自行设计铣削靠模装置和车床改造,使之能够车床代替铣床进行方形曲面槽加工,并通过车床改造与生产证明了车床代替铣床改造的加工效果,解决了零件加工长度超过X62铣床纵向行程长度的问题,并对方形曲面槽的加工能有效地减少对大型机床设备的投资,这种加工方法是符合实际情况。 相似文献
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Novel circularly-polarized ceramic dielectric resonator antenna excited by a corner-cut square patch
A ceramic dielectric resonator antenna excited by a corner-cut square patch for the circularly-polarized operation is introduced.
The effect of patch size and cut size is investigated, showing that the resonant frequency of the antenna can be changed by
simply changing the patch size. The reflection, axial ratio, and radiation characteristics of the antenna are found. Measurements
were carried out to verify the design. The antenna is compact in structure, which is attractive in the application as the
satellite communication terminals. 相似文献
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