人工触发闪电电流测量及特征性分析

通过对１９９３年７月２７日的人工触发闪电电流、跨步电压的直接测量结果的分析发现,在正电场下触发的慢型放电过程由连续电流和双极性的电流脉冲过程组成,其放电特性与雷暴的电特性有关。闪电电流最大值为１．２ｋＡ,持续时间为２５ｍｓ,中和电荷量为８．９Ｃ。跨步电压与电流的测量结果相一致,是一种间接测量电流的方法。     

合肥遥测台网地震速报系统

论述了适用于遥测地震台网大震速报的一套计算机处理系统,系统设计以《全国遥测台网观测技术规范》和《近震分析》理论为依据,实现了数据输入,震相选择,数据处理,地震定位,震级计算,结果输出及贮存等多项功能,达到了快速确定地震三要素,提高速报速度和精度之目的,是一个较完善的,实用的速报系统。     

The effect of an optically thin region on stability of an accretion disk around a supermassive black hole

We analyse conditions of the innermost portion of an accretion disk and establish a set of equations for this region. A stable innermost region may exist, which can probably explain the observed UV and X-ray spectra, avoiding the unstable emission. We then discuss the detailed radial structure of a disk around a black hole for typical AGN parameters and obtain different kinds of- relationships for different regions of a disk. On the basis of this, we discuss the stability. A new type of cycle is present, which we call a double S shaped cycle. In this cycle, the extent of accretion rate variability is much larger than that in dwarf nova cycles. This probably solves the problem of violent variability of AGN. In the meantime, the very high accretion rate at the hottest state in limit cycles in the unstable region may provide continuous injection of matter to the jet and power the relativistic motion of the jet.     

国家经济地图集的设计和制图可视化的方法技术

国家经济地图集是第一部全面,系统反映我国当前经济社会发展面貌和空间分布的大型科学参考地图集,它的编制是一项重大的制图系统工程,本文简要地阐述了图集编制研究的主要方面,包括从分析我国经济社会发展和现状出发,确定图集设计总体目标,为科学和形象地表达我国经济社会特征,而采用的可视化方法技术,以及智能化的计算机制图系统在图集制中的应用。     

基于GIS的TM数据分类及辅助制图研究

本文初步研究了遥感、GIS和制图一体化实用技术方法。对黄土丘陵区和沙漠地区TM数据进行了特征信息分析;给出了分层分类和GIS辅助分类结果;经模糊推理和人机交互修改,将提“纯”的遥感专题数据作为GIS的动态信息源,对GIS进行扩充与更新;最后在GIS支持下分层提取专题图并进行辅助制图。     

冀西北长城纪宣龙式铁矿层中微体植物化石的发现及其意义

本文研究的是笔者等在冀西北长城系串岭沟组宣龙式铁矿层中发现的微体植物化石,这些化石都保存在铁质叠层石(肾状赤铁矿)和铁质核形石(鲕状赤铁矿)的基本层中。微化石以丝状体为主,部分为球状体。归属于原核生物蓝藻门颤藻科的两个属和色球藻科的一个属。化石层同位素年龄约在1800—1757Ma。这些化石与北美冈弗林特组微化石比较,既有些相似,又有些区别。该化石的发现为研究铁矿的成因,指示沉积环境及层位对比都很有意义。     

Exploiting the dual functions of polymer depressants in fine particle flotation

Fine hydrophilic particles are known to be entrained with water in flotation of many ores. Flocculation of the hydrophilic particles by polymer depressants could potentially reduce the mechanical entrainment of these particles. This paper reports testwork completed on fine particles of several solids, iron oxide, hydroxyapatite and sphalerite, as well as on a relatively coarse quartz sample (− 75 + 38 μm). Dodecylamine was used as a collector for quartz, and several dispersants and polymer depressants, including sodium silicate, sodium metaphosphate, zinc sulfate, cornstarch, corn dextrin and carboxymethyl celluloses (with molecular weights of both 700,000 and 80,000) were used as flotation modifiers. The major part of the testwork involved flotation tests in a 200 mL flotation column. It was observed that flocculation of the fine hydrophilic particles significantly reduced their mechanical entrainment, while dispersion severely aggravated it. Thus, in the flotation separation of synthetic mixtures of the − 75 + 38 μm quartz and fine (reagent grade) iron oxide or hydroxyapatite, polymer depressants that caused flocculation performed better than those that did not cause flocculation.     

中国古代常规日食记录的整理分析

收集并分析了公元前8世纪到公元15世纪的中国古代密集、简略而公式化的日食记录。基于这些记录整理成一个包括938条日食记录的计算机可读形式的“常规日食记录表”。该表给出每次记录的原日期、公历日期、当时首都、所属朝代以及一部分记录所载的进一步详情。对该表的构成作了介绍,并对这些历史记录进行了初步的分析和归纳。