首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
本文报导了对铀、锌、铜和锂四种元素具有一定吸附性能的几种钦复合吸附剂研制,其中筛选出钛(Ⅳ)铁(Ⅲ)复合吸附剂较佳,它的制备条件是Ti/Fe(摩尔比)=1/0.5,沉淀pH值为6.0,在加浓铀的人工海水中它的吸铀量为15717微克/克干剂,在天然海水中,逆流通海水十天,它的吸铀量亦是同类吸附剂中较高的,述到114.6微克/克吸附剂.另外,这种复合吸附剂在天然海水中吸铜量是16.55微克/克吸附剂,亦是较高的,它在天然海水中吸锌量是256.1微克/克吸附剂,吸锌量也是较高的.这些结果,对海水综合利用、废水利用环境保护方面等,都有重要的参考价值. 另外,在钛复合附剂电性和结构方面的研究,都取得较有价值的信息.吸铀量大的吸附剂,ξ电位绝对值有小的趋势.产生异质同晶的吸附剂吸铀量与吸锌量都较大.  相似文献   

2.
本文报导了对铀具有一定吸附性能的T_i(Ⅳ)一C_r(Ⅲ)复合吸附剂的研制,其中筛选出T_i/C_r(摩尔比)=1/0.1,沉淀PH为6.0,制备温度为40℃的复合吸附剂TCl的吸铀性能最佳。在加浓人工海水中它的吸铀量为8091微克/克千剂。在天然海水中逆流通海水十天,它的吸铀量也是同类吸附剂中最高的,达到105.37微克/克吸附剂。另外,在复合吸附剂的电性方面的研究,取得较有价值的信息,吸铀量大的吸附剂,ξ电位绝对值有小的趋势。  相似文献   

3.
本文报导了对铀、铜和锌具有一定吸附性能的Al(Ⅱ)一Fe(Ⅲ)复合吸附剂的研制。其中筛选出Al/Fe(摩尔比)=1/0.5,沉淀PH值为8.0,制备温度为40℃的复合吸附剂AF3的吸铜、锌性能最佳。在天然海水中吸铜量和吸锌量分别为12.92微克/克吸附剂和199.4微克/克吸附剂。在50mg/1的Cu~(2+)溶液中吸铜量达到42.5毫克/克吸附剂,在50mg/1的Zn~(2+)溶液中吸锌量达到49.0毫克/克吸附剂。这些结果,对海水综合利用,放射性废液处理,矿业和废水处理都有重要的参考价值。  相似文献   

4.
本文报道一种机械强度高,吸铀性能较好的TS系列玻璃钛吸附剂的研制及吸铀性能研究。室内通水吸附剂回收率达99.4%,优于湿法制备的强度较好的水合氧化钛吸附剂。在铀浓度为1微克/毫升时,铀的回收率平均为74.7%。铀在玻璃钛上的吸附是个吸热过程,吸附等温线显示二个平台,属分级交换模式。X射线衍射分析表明玻璃钛主要为无定形成分。  相似文献   

5.
本文报道一种机械强度高,吸铀性能较好的TS系列玻璃钛吸附剂的研制及吸铀性能研究.室内通水吸附剂回收率达99.4%,优于湿法制备的强度较好的水合氧化钛吸附剂.在铀浓度为1微克/毫升时,铀的回收率平均为74.7%.铀在玻璃钛上的吸附是个吸热过程,吸附等温线显示二个平台,属分级交换模式.X射线衍射分析表明玻璃钛主要为无定形成分.  相似文献   

6.
1.TO-35吸附剂(水合氧化钛的编号)在UO_2(ClO_4)_2水溶液中的吸铀量随着溶液pH值的减小而增大.由于吸铀量的增大,在2θ=26.8°的新衍射峰高度亦随之增高,所以,认为是以UO_2~(2 )离子形式被吸附. 2.TO-35吸附剂是锐钛矿型. 3.吸铀后的TO-35,在2θ=25.1°处衍射峰高度比空白吸附剂都明显增高,这可能是由于TO-35对UO_2~(2 )进行化学吸附所致. 4.钛吸附剂吸附UO_2~(2 )离子以后,它有一个最高的特征衍射峰在2θ=26.8°,这在国内外都未见过报导.  相似文献   

7.
本文通过对研制的一系列钛一铁复合吸附剂的吸铀实验及固一液界面电性质实验进行比较,得到了性能较好的吸附剂,与纯钦吸附剂相比具有吸铀量高、吸附速率快、吸铀量受温度影响小、易回收和造价便宜等优点。  相似文献   

8.
用于海水提铀的钛吸附剂的吸附容量与水分有很大关系。所以,钛类吸附剂中水分的研究对改进钛类吸附剂的性能、研究它的吸附机理都有重要的意义。本文用改进后的微量差热装置(作者自装),在慢速升温的条件下,把几种处于不同状态的水分,在微量差热曲线上的峰得到较好的分离。这对吸附剂的吸附性能的进一步研究具有重要的意义。  相似文献   

9.
什么是贫铀武器 铀就在我们周围,它和钨、铅、镉等一样,是重金属,在自然界土壤中的平均含量为百万分之三,好比一货车泥土,铀的量约有一大汤勺.我们每天都会通过空气、水和食物摄入一定量的铀.平均来说,我们每天通过食物和水摄入铀的量为1.9微克(约百万分之二克),从空气中吸入的铀则极少,每天为0.007微克.  相似文献   

10.
铀在钛酸吸附剂上的特性吸附   总被引:2,自引:1,他引:1  
有关钛酸吸附剂提取海水中铀的研究,已进行得很多,但从固-液界面化学行为的角度去研究吸附机理,则报道极少.本文用微电泳法研究了钛酸吸附剂在吸铀前后的电动电位变化及计算了铀在不同pH溶液中的溶存状态分布.根据实验事实及双电层理论分析,推断钛酸吸附剂吸铀,属于特性吸附,其特性吸附自由能为△G_s=-8~-9千卡/摩尔.钛酸吸附剂主要与水溶液中含铀酰的带正电荷质点起化学作用形成表面络合物,使表面电位升高.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
19.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号