水准测量

Overall, 1212 MU were required for each field. Beam flatness was within ±5% and ±10% in the vertical and horizontal dimensions, respectively. Thermoluminescent dosimeters were used to evaluate dose homogeneity at 45 sites.

每一成对照野的射束各与水准轴成上或下20度之夹角，倍率系数经测量为2.68，肿瘤剂量定於皮肤表面下5毫米处（位於90%等剂量曲线），总计每单一照野的照射必须1212 MU。

Project construction is in the national spatial coordinate reference frame, based on the use of high-tech means of Geodesy, in Baotou city, the information on outcomes and quality of the original plane, gravity surveying and mapping information, etc. Based on the results, in accordance with unified planning and overall design principles, laid covering the city's domain sets plane, elevation, gravity field information based on the integrated control network formed by the geodetic datum, elevation and gravity reference base composed of high-precision, three-dimensional center of the earth and practical reference Baotou modern surveying and mapping system for the "Digital Baotou" construction and large-scale mapping projects such as surveying and mapping provides a unified spatial orientation reference.

项目建设是在国家空间坐标基准框架的基础上，利用大地测量的高新技术手段，在包头市原有平面成果资料和水准、重力资料等测绘成果的基础上，按照统一规划、整体设计的原则，布设覆盖全市域集平面、高程、重力场信息于一体的综合性基础控制网，形成由大地基准、高程基准和重力基准等组成的高精度、三维地心、实用的包头市现代测绘基准体系，为&数字包头&建设和大比例尺测图等测绘工程提供了统一的空间定位基准。

The function of astronomical leveling in height survey of position traverse control network is introduced.

简要介绍了天文水准在阵地导线网高程测量中的作用。

The geoid is used to be regarded as the theoretic global vertical reference .The actual national height references are regional mean sea levels determined by tide gauge station. The difference between them is apparent. The satellite altimetry has developed as a kind of important space geodetic technique since 1970s.

大地水准面作为全球高程测量的理论基准面，在现实工作中，国家或者地区高程系统的起算面是利用验潮方法来确定局部平均海平面的，两者之间的差距是显而易见的。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。