铁基样品中锰的中子活化法测定   总被引：1，自引：0，他引：1  

侯小琳 《岩矿测试》1996,15(3):188-191

采用热中子与超热中子照射相结合的中子活化法测定了铁高含量样品中锰的含量。实验测定和理论计算了铁对锰的干扰系数，两者符合较好。对几个标准物质的分析结果与推荐值相符。该方法适用于ｍＦｅ／ｍＭｎ小于２×１０５的样品中锰含量的测定  相似文献   

亳州市电视铁塔倒塌事故的气象原因   总被引：3，自引：2，他引：3       下载免费PDF全文

吕升亮  王兴荣  陈晓平  程小泉 《气象》2001,27(2):52-54

通过实地调查和气象资料分析，得出造成1999年8月30日亳州市教育电视台电视铁塔倒塌事故的气象原因是由于受飑线袭击，铁塔承受了超过满足国家GBJ9－87所规定的铁塔设计风速，此外铁塔位于形成喇叭口形状的两座高楼中的一座上，两座高楼由于特殊结构而形成狭管效应，造成局部风速增大，使铁塔所承受风速比开阔地的风速还要大，从而造成倒塌事件。根据这一分析，得出一些有益结论，能对高层建筑与铁塔建筑设计规范的修正提供借鉴意义。  相似文献   

Comparison of the Concentrations of Chemical Components in Cloudwater Samples Collected during Four Different Field Campaigns     

F. Deutsch  P. Hoffmann  H. M. Ortner 《Journal of Atmospheric Chemistry》2001,40(3):295-304

In this study, the results of four different field experiments concerning the speciation of iron and the concentrations of some other chemical compounds in cloudwater samples are compared to one-another. Hydrogen peroxide concentrations were higher during campaigns, conducted at sites not much influenced by anthropogenic emissions as compared to those conducted at more polluted areas. In contrast, percentages of S(IV) in the cloudwater were lowest at the rural sites and highest at the sites polluted by human activities, indicating a consumption of hydrogen peroxide in the oxidation reaction with S(IV). The concentration of dissolved iron was observed to correlate with the percentage of S(IV), which may be an essential point for the reductive dissolution of oxidic iron compounds of the aerosol particles. As far as the speciation of the dissolved iron is concerned, it became obvious that the percentage of Fe(III) is anticorrelated to the concentration of dissolved iron. This clearly shows the important effect of the chemical and/or photo reductive ways of dissolving the iron(III)-compounds from the aerosol particles. However, a correlation between the pH-value and hydrogen peroxide was observed.  相似文献   

无机高分子絮凝剂絮凝机制的研究进展   总被引：9，自引：0，他引：9  

万鹰昕  程鸿德 《矿物岩石地球化学通报》2001,20(1):62-65

近年来无机高分子絮凝剂的研究已成为水处理药剂研究的热点。本文概述近年来无机高分子絮凝剂絮凝机理的研究进展 ,包括我们所最近研制的三系列含水聚硅酸铝铁钠废水净化剂 ,它们的优缺点及其絮凝机理。重点阐明研制絮凝剂时通常采用共存阴离子和活性硅酸与铝盐或 /和铁盐的聚合作用 ,并探索絮凝剂中各组分对絮凝剂的絮凝效果的贡献。  相似文献   

Re-Os同位素体系在陨石研究中的应用   总被引：2，自引：1，他引：2  

杨刚  谢智  陈江峰 《地学前缘》2001,8(2):339-344

铁陨石中的Re ,Os含量反映其结晶分异历史。通过铁陨石定年修正187Re的衰变常数为 :λ(187Re) =1 6 6 6× 10 -11a-1。ReOs同位素测年法可以直接用于对铁陨石的定年 ,结果表明天然铁陨石大体同时形成 ,但ReOs定年技术已有可能揭示不同化学群铁陨石形成年代的序列 ,但研究尚需深入。这些方法也可以用来探讨铁陨石和石铁陨石的形成源区、冷却历史和后期变化。虽然在石陨石中Re ,Os同位素的浓度很低 ,但也有了探索性研究成果。随着技术的不断发展 ,ReOs同位素体系在天体化学中的作用将愈加明显和重要。  相似文献   

新构造断裂对莱芜铁矿田中岩溶地面塌陷的控制作用   总被引：1，自引：0，他引：1       下载免费PDF全文

刘建茂  郑文忠 《地质找矿论丛》2002,17(4):282-286

莱芜铁矿田中，一般情况下地表水、第四系潜水与岩溶水无水力联系，地表无塌陷产生，只有在新构造断裂发育的地段，才有可能产生岩溶地面塌陷。而在这些地质，灰岩顶部岩溶裂隙发育的程度，覆盖层结构，地表水、第四系潜水与岩溶水的水力联系均有新构造断裂控制，而这几方面正是岩溶地面塌陷产生的必要条件，所以，莱芜铁矿田中的岩溶地面塌陷由新构造断裂控制。  相似文献   

电子探针定量分析直接测定含铁矿物中二价和三价铁     

陈克樵  欧阳菲 《岩矿测试》1992,(4)

研究表明,含铁矿物中铁的平均价态(反映Fe~(2+)和Fe~(3+)含量)与Fe Lβ/Fe Lα值呈正比关系曲线。未知样品只要测得TFeO含量和Fe Lβ、Fe Lα的计数值,就可以分别获得FeO和Fe_2O_3的定量分析结果。经几种含铁矿物测定实例验证,说明方法可行。  相似文献   

火山岩中交代岩和铁矿的实验研究   总被引：4，自引：1，他引：4  

梁祥济  乔莉 《岩石矿物学杂志》1991,10(4):300-314

本文作者在火山岩地区的新疆磁海、雅满苏和内蒙黄岗梁三个铁矿床进行野外工作的基础上,模拟火山气热液与次火山岩-火山岩(辉绿岩、安山质凝灰岩、安山岩和凝灰质砂岩)相互作用。实验结果证明了在380—700℃和(250—800)x105Pa的温度和压力下形成了与上述三个矿床相似的交代岩的矿物共生组合,并且从次火山岩-火山岩中萃取出TFe(11.89—3881.89mg/1)。由此可见,晚期火山气热液继续沿构造断裂上升,作用于沿途所经过的早先形成的次火山岩-火山岩,从中萃取出大量的铁,并在适宜的温度和压力等物理化学条件下形成了磁海、雅满苏和黄岗梁(西段)铁矿床。  相似文献   

Measurement of total dissolved phosphorus in small volumes of iron rich interstitial water     

René Gächter  André Tessier  Erno Szabo  Richard Carignan 《Aquatic Sciences - Research Across Boundaries》1992,54(1):1-9

It is shown that sorption of orthophosphate to iron compounds, formed during persulfate digestion, can cause a significant underestimation of total dissolved phosphorus in interstitial waters rich in iron and poor in phosphorus. Labelling the samples with carrier free³²PO₄ before digestion allows to correct for these losses.  相似文献   

Sulfides in Sandy Sediments: New Insights on the Reactions Responsible for Sedimentary Pyrite Formation     

John W. Morse 《Aquatic Geochemistry》1999,5(1):75-85

The formation of sedimentary iron sulfides was studied in sandy sediments of the Laguna Madre, TX, in order to better understand how this process operates in sediments where reactive iron is likely to be limiting for sulfide mineral formation. These sediments usually had reactive iron and total reduced sulfide concentrations one to two orders of magnitude less than in typical shallow water terrigenous muds, but organic-C concentrations typical of fine-grained sediments due to the extensive presence of seagrass beds. This resulted in moderate (0–150 m) dissolved H2S concentrations with maximum concentrations in the upper (3–:5 cm) root zone. Based on citrate dithionite extractable-Fe the degree of sulfidization was usually 100% or greater. Acid volatile sulfides (AVS) typically comprised roughly 60% of total reduced sulfur and the proportion of AVS generally increased instead of decreasing with depth. The unusual proportion of TRS as AVS and persistence of AVS are attributed to exceptionally slow pyrite formation kinetics. The probable reasons for these slow reaction kinetics are the high (>7.8) pH of the sediments, which favors the slow polysulfide pathway for pyrite formation, high (typically about 2–4 mm) dissolved organic carbon concentrations that inhibit growth of pyrite and the low concentration of reactants which greatly increases the average transport distances necessary for diffusion controlled reactions.  相似文献