建立作为1∶10000比例尺和等高线间隔为一公尺地形测量的测图控制的特点(续前)

测图导线在敷设测图导线时,可以采用为敷设基本高程导线所用的同样的仪器（工程水准仪）,以及望远镜上附有水准器的远镜照准仪,和附有垂直度盘或附有斯托多耳凯维奇高程折光镜的普通远镜照准仪。现有的实施细则主要规定这样的工作布置,即：当水准仪仅应用为敷设基本高程导线时,测图导线,照例,则用平板和远镜照准仪来敷设。如果远镜照准仪的望远镜上没有附有水     

CONCENTRATION AND FLUX OF CO_2, TURBULENCE FLUXES AND RADIATION BALANCE IN THE NEAR SURFACE LAYER OVER WHEAT FIELD

The gradient of CO_2 concentration, photosynthetically active radiation (PAR). net radiation.soil heat flux, profiles of wind speed, and air temperature and humidity were measured above awheat field during May and June 1985 at Beijing Agro-Ecosystems Experimental Station. Beijing,China. Fluxes of carbon dioxide, sensible heat, latent heat and momentum were calculated byusing the aerodynamic method. The observation site. equipment, calibration techniques, theerrors associated with the measurement, and the computational procedures are described. Theresults show that the diurnal variations of amplitude of CO_2 concentrations were 103.8 to 27. 0. 86.3 to 22.8 and 69.8 to 11.6 ppm: the average CO_2 concentrations were 331.5. 339.9 and 364.6 ppmfor the photosynthesis type, and 369.6. 364.0 and 375.2 ppm for the respiration type at 1. 2 and10 m above surface, respectively, from May 14 to June 15. In the daytime, transfer direction ofthe CO_2 fluxes and gradients is from air to crop canopy, and at noon (1100 to 1300 BT (BeijingTime)) the transfer rate reaches negative maximum value. At night, transfer of CO_2 fluxes andgradients is in the reversed direction and reaches positive maximum in the early morning (0400 to0600 BT). There are strong negative correlations between CO_2 flux and the net radiation (Rn),available energy (H LE). photosynthetically active radiation (PAR) and momentum flux (τ).     

白云鄂博REE-Nb-Fe矿床成因的氧、碳和锶同位素及微量元素地球化学证据

根据白云鄂博赋矿白云石大理岩的岩石学特征及地质产状将其分为两类：粗粒和细粒白云石大理岩．它们的氧、碳和锶同位素及微量元素地球化学特征显然有别于分布在宽沟背斜以北典型的沉积石灰岩和白云岩,而和幢源火成碳酸岩十分相似．与矿床进行对比研究说明,成矿流体和矿质主要起源于碳酸岩浆的分异作用,其放射性成因同位素和微量元素保持了地但指纹,而氧和碳同位素组成却向壳源方向漂移,证实碳酸岩浆侵位过程中受大陆地壳的混染作用非常微弱,但是由碳酸岩浆活动所引起的成矿热液体系中却有一定的地表水混人认为白云鄂博REE-Nb-Fe超大型矿床的成因应归属于火成碳酸岩型矿床．     

热带气旋周围15米/秒风的半径和频率

1.引言海上交通常受台风海浪的影响。为了最大地保证船只的安全以及减少船只改变航线而付出的代价,我们必须预报出大风的水平范围。对于海面状态,地面风速为15米/秒的半径是一个重要的参数。本研究使用西北太平洋和西大西洋的无线电测风资料,计算了离台风和飓风中心各个距点上地面风≥15米/秒的发生概率。文章探讨了15米/秒等风速线与风暴强度和范围之间的关系,还讨论了沿     

“长生鸟计划”概述——介绍一个行星边界层试验研究计划

1.引言美国海洋大气局(NOAA)波传播实验室(WPL)和美国国家大气研究中心(NCAR)大气技术部(ATD)会同其它一些单位,于1978年9月在博尔德(Boulder)观象台(BAO)进行了一次大规模的野外试验,取名为“长生鸟计划”。该计划动用了装有探测仪器的飞机、地面气象网、雷达、激光雷达、声波探测器、微波辐射计、光学测风仪、无线电探空测风仪、定高气球以及为积累基本资料用的     

苏联土尔盖地区火山——沉积类型铁矿床

与沉积-火山地层同生的矿石暂时仅在三个矿床内查明:伊尔泰I、Ⅱ和Ⅳ,并已被一系列勘探钻孔所揭示。但分布面积不大,因此关于它们在矿区中特别是在矿带中的分布特征了解较少。所见该类型矿石在空间上均与交代矿石相伴生的特征十分明显。在海底喷发条件下带出,并随之在火山口附近或某一距离内沉积的金属物质所形成的矿石,属于火山-沉积类型(B·N·斯米尔诺夫等)。这里并不排除部分金属物质可能由火山岛或毗邻大陆呈易溶化合物状态被带入。由此可见,矿石的铁质来源可以是不同的。     

地震形变的断层分层、分段活动模式

采用横向分段、纵向分层的断层位错模式研究了美国加州帝国河谷地区四期三角复测资料,确定了1940年该河谷地区的M_ W=7.1级地震的断层活动方式及震后不同时期的滑动速率。 模式的要点是:大震间歇期发震层(孕震层)是闭锁或接近于闭锁状态,地表浅层和地壳深层可以发生无震滑动(蠕动);地震发生时,浅层与发震层产生滑动,且滑动量沿断层呈非均匀分布。     

Is China Over-Populated?

The object of this paper is to show that the general poverty of the Chinese people is not caused by over-population, but by the primitive methods of production, the existing system of exploitation, the political chaos and the political and     

Is China Over-Populated?

The object of this paper is to show that the general poverty of the Chinese people is not caused by over-population, but by the primitive methods of production, the existing system of exploitation, the political chaos and the political and