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1.
研究了不同的热处理制度对La2O3-MgO—Al2O3-SiO2-ZnO微晶玻璃系统微波介电性能的影响。应用X射线衍射(XRD)分析了它们的晶相组成,结果表明,ZnO质量分数为14%的样品在600℃保温不同时间,其介电常数温度系数(τε)在115.9×10^-6/℃~-81.8×10^-6/℃线性可调,相应的主晶相由MgSiO3变为ZnAl2O4,证明了晶相的组成及其相对质量分数是介电性能变化的根本原因。在600℃保温7h,850℃保温40h获得的样品的参数为:ετ=14.301;Q=1437;ετ=2.5×10^-6/℃。  相似文献   

2.
掷孢酵母对含铬废水的生物吸附   总被引:4,自引:0,他引:4  
研究了掷孢酵母(Sporobolomyretaceae sp.)对含铬电镀废水的生物吸附性能.结果表明,废水的pH值和菌体的培养时间是影响该废水生物吸附的重要因素,适宜的pH为3.5~5.3;培养时间为55~72h.活性污泥的联合使用能有效地促进铬的生物吸附效果.当污泥质量(湿)浓度为10g/L时,25g/L菌体对34.4mg/L总Cr的去除与33.0mg/L Cr^6+的还原分别高达87.3%、91.9%.对吸附机理和毒性的初步探讨结果表明,菌体对铬的吸附由表面吸附、跨壁膜运输和体内积累组成,其中体内积累对吸附的贡献值最大,达到总吸附量的70.6%;细胞壁对铬毒性的抗性理想,300mg/L铬不会对细胞壁产生0.1nm以上的形态破坏:活性污泥的联合使用有助于铬的还原。  相似文献   

3.
研究了山荷叶叶柄愈伤组织的诱导、分化、试管苗生根、移栽所需要的条件,并建立起山荷叶的无性系.结果表明:MS+La(NO3)3·6H2O 1.2mg/L+BA0.5mg/L+NAA1.5mg/L是山荷叶叶柄愈伤组织诱导的理想培养基;MS+La(NO3)3·6H2O 1.2mg/L+BA0.5mg/L+IAA 0.2mg/L是山荷叶愈伤组织分化的理想培养基;1/3MS+IAA 0.5mg/L是生根培养的理想培养基;以炉灰渣为试管苗的移栽扦插基质,移栽成活率为91%;试管苗在原产地生长正常.  相似文献   

4.
添加氧化锆对钢渣微晶玻璃显微结构的影响   总被引:1,自引:0,他引:1  
采用熔融法制备微晶玻璃材料,探讨了钢渣微晶玻璃中引入ZrO2对其显微结构以及性能的影响。用X衍射仪和扫描电镜分析了微晶玻璃的主晶相和显微结构。实验结果表明:引入质量分数为1%的ZrO2时,微晶玻璃的晶粒最小,抗弯强度最大;当ZrO2的添加量进一步增多,晶粒无法发育完全且晶相含量下降,导致微晶玻璃的抗弯强度降低。在该钢渣微晶玻璃中,ZrO2最佳添加量的质量分数为1%。  相似文献   

5.
2005年4月,以在浙江舟山普陀兴海养殖优质种苗选育研究所取得的三疣梭子蟹各期涵状幼体作为实验动物,开展了Hg^2+、Cu^2+、Zn^2+、Cr^6+4种重金属离子对其急性毒性实验.结果表明:三疣梭子蟹幼体对重金属的耐药性均随实验时间延长而明显降低,4种重金属离子对三疣梭子蟹各期幼体的毒性大小依次为Hg^2+、Cu^2+、Zn^2+、Cr^6+,三疣梭子蟹苗种培育中对Cu^2+、Hg^2+、Zn^2+、Cr^6+的安全质量浓度取值分别为0.0156mg/L、0.0025mg/L、0.0686mg,/L和0.5230mg/L.  相似文献   

6.
利用油页岩渣制备微晶玻璃   总被引:1,自引:0,他引:1  
以油页岩渣为主要原料制备了微晶玻璃,探讨了微晶玻璃组成、主晶相确定和晶核剂选择等问题.采用DTA,XRD和SEM等测试手段,分析了晶核剂和热处理制度对微晶玻璃的影响.结果表明:复合晶核剂(TiO2+P2O5)能有效促进油页岩渣玻璃晶化;最佳热处理制度为:850℃核化100 min,980℃晶化80 min.微晶玻璃的主晶相为钙铁透辉石,次晶相为钙长石;晶体呈纤维状结构并且交错分布;性能明显优于同类的瓷质砖、大理石和花岗岩等建筑装饰材料.  相似文献   

7.
"马可"百合组培技术研究   总被引:3,自引:0,他引:3  
以“马可”百合(Lilium bulbiferum cv.‘Marco Polo’)鳞片为起始外植体,MS为基本培养基,以不同激素成分及不同浓度水平来诱导“马可”百合产生小鳞茎。结果表明:“马可”百合的诱导可由外植体直接产生小鳞茎而分化成苗。诱导“马可”产生小鳞茎的最佳外植体为鳞茎内部的鳞片,将其作为不切开处理,并以鳞片远轴面紧贴培养基的方式进行接种,在MS+6-BA(1.0mg/L)+IBA(0.3mg/L)培养基上进行诱导培养,其平均分化系数达2.52。“马可”百合最佳扩繁增殖培养基为MS+6-BA(0.3mg/L)+IBA(0.3mg/L),小鳞茎的增殖系数可达2.60。采用1/2MS+6-BA(0.3mg/L)+IBA(0.7mg/L)的培养基对“马可”进行生根培养,根条数可达8.0,生根率为100%。“马可”生根苗应用质量分数为50%多菌灵800倍液进行消毒处理,移植于河泥和珍珠岩的体积比为7.3的基质中,成活率可达98%。  相似文献   

8.
本文以铬渣和铜尾矿为原料,采用熔融法制备微晶玻璃,借助XRD和SEM等分析手段,系统研究了晶化温度对微晶玻璃析晶行为的影响;研究结果表明:随着晶化温度的升高,微晶玻璃的主晶相均为普通辉石,且晶体尺寸增大,晶核数量减少,同时微晶玻璃的表观体积密度和显微硬度呈先增大后减小的趋势,当晶化温度为860℃时,表观体积密度和显微硬度达到最大,其值分别为3.06g.cm-3和925Hv。  相似文献   

9.
山西翼城高炉渣在微晶玻璃中的应用   总被引:1,自引:0,他引:1  
以山西翼城高炉矿渣为主要原料,采用烧结法制备微晶玻璃.利用差热分析仪(DTA)、扫描式电子显微镜(SEM)、X射线粉末衍射仪(XRD),研究矿渣微晶玻璃的成分、制备工艺,以及对显微结构和性能等进行分析.研究结果表明,当基础玻璃化学组成(质量分数)分别为50%~60%(SiO2),4%~8%(Al2 O3),14%~19%(CaO),7%~10%(MgO),0.7%(Fe2O3),4%(Na2O),6%(K2O)时,主晶相为透辉石,高炉渣最大引入量达到47.35%,最小量为28.06%,可以获得性能良好的烧结型微晶玻璃.  相似文献   

10.
利用粉煤灰与石英砂制备微晶玻璃,并对其进行不同工艺的热处理.通过对热处理后的试样研究发现:当粉煤灰质量分数为30%,未加TiO2时,试样在780℃加热时首先析出过渡相Ca2SiO。,在随后的高温晶化过程中,过渡相溶解消失,析出更稳定的平衡相钙长石;当TiO2质量分数为0—15%时,随着TiO2含量的增加,在780℃加热时由析出梭形的Ca2SiO。微晶转变为析出粒状的钙长石微晶;当粉煤灰质量分数增加到40%,TiO2质量分数为3.5%时试样中出现网状微晶组织,而加入的形核剂TiO2质量分数达到5%时试样中无网状微晶组织出现,说明TiO2对网状组织的析出具有明显抑制作用.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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