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1.
用 pH测定法、溶解度法和分光光度法测定了铀试剂Ⅲ的八个离介常数,在离子强度等于0.1时它们分别为: K1=13±1.2; K2=(2.4±1.1)×10-2, H3=(9.6±1.1)××10-4;H4=(3.3±0.1)× 10-5;K5=(5.4±0.3)×10-8;K6=(1.0±0.2)×10-9;K7=(4.7±0.4)×10-11;K8=(4.7±0.5)×10-13。并根据这些常数作出了试剂离介形式随PCH的分布图。  相似文献   

2.
鲢鱼幼鱼对盐,碱耐受性的研究   总被引:6,自引:1,他引:5  
利用盐碱地区氯化物型地下水进行了鲢鱼幼鱼(L=5.4 ̄8.2cm)对盐度(pH=8.60±0.18)、碱度(pH=8.74±0.34)及盐碱混合的急性毒性试验。研究结果表明:鲢鱼幼鱼对盐度的24、48、72和96h的半致死浓度(LC50)分别为:11.2,9.0,8.6和8.2g·L^-1;对碱度的相应LC50值分别为51.4、27.1、23.7和15.7mmol·L^-1。盐碱混合的正交试验表明  相似文献   

3.
锇—钼酸盐—碱性染料显色反应的研究   总被引:1,自引:0,他引:1  
在聚乙烯醇存在下,锇与钼酸铵和碱性染料罗丹明B,丁基罗丹明B,耐尔蓝形成离子缔合物,不同碱性染料所形成的缔合物服从比耳定律的浓度范围和摩尔吸光系分别是:0-1.2μg/25ml和ε570nm=2.62×10^6L.mol^-1cm^-1;0-1.0μg/25ml和ε570nm=2.86×10^6L.cm^-1;0-1.8μg/25ml和ε585nm=2.81×10^6L.cm^-1;0-1.8μg  相似文献   

4.
细胞显微电泳表明,介质PH值对离体玉米精细胞电泳迁移率有较大影响,在HClGly(甘氨酸)缓冲液中,其等电点介于PH2.4-3.0;在PH6.7的MES缓冲液中,电泳后统计分析表明,离体玉米精细胞可以区分为电泳迁移率有差异的2种类型,其电泳迁移率分别为(1.803±0.043)×10^-6和(1.667±0.052)×10^-6m^2.V^-1.s^-1。根据电泳迁移率的差异,利用一种支无持细胞电  相似文献   

5.
藏山羊产乳性能和乳酶及乳清蛋白的测定   总被引:2,自引:4,他引:2  
对分布于青藏高原地区和山谷地区藏山羊的泌乳性能和乳清蛋白组分,及山谷地区域山羊乳酶力进行了测定,结果表明:高原地区藏山羊产乳量平均为24.0kg,乳中营养成分含量(%):乳脂为4.8±1.2、乳糖为4.59±0.75、乳蛋白为4.87±0.61;山谷地区藏山羊产乳量平均为36.62kg,乳中营养成分(%),乳脂为5.3±1.5、乳糖为4.99±0.45、乳蛋白为3.08±0.48.山谷地区的藏山羊乳酶,LDH、AKP,R-GT和LP和活力分别为81.9±37.8、7.7±3.5、437.4±93.0、532.7±202.6单位,LP在体外可被10 ̄(-5)mol/L的硫氰酸根或乳酸根活化,经琼脂糖凝胶平板电脉,可将乳LDH分离出LDH_1、LDH_2和LDH_3三条带,各带所占有百分比分别为50.6±4.5、31.6±4.2和17.8±3;3.采用SDS-pAGE,乳清蛋白显示出五条区带,即SA、Ig-H、Ig-l,β-Lg和α-La。乳清蛋组分(%):高原地区藏山羊SA为6.6±3.0、Ig为22.9±6.5、β-Lg为47.5±9.1和α-La为23.0±10.6;山谷地区藏山羊相应为6.6±2.6、2  相似文献   

6.
通过一系列滴定量热测定,求得了298.15K时十二钨硅酸及其6DMF、8DMSO加合物的标准生成焓,其数值分别为-(13.14±0.01)×10^3KJ·mol^-1、-(13.61±0.01)×10^3KJ·mol^-1及-(13.86±0.01)×10^3KJ·mol^-1。  相似文献   

7.
邻菲咯啉钌(Ⅱ)化学发光分析测定环丙沙星   总被引:5,自引:0,他引:5  
试验表明,在0.01mol·L^-1 NaAc-HAc(pH5.0)底液中,环丙沙星能增强Ce(Ⅳ)氧化Ru(phen)2/3+检测限为4.4×10^-8g·mL^-1,其相对标准偏差分别为2.8%和3.3%,该法用于片剂中环丙沙星含量的测定,获得满意结果。  相似文献   

8.
复合型纳滤膜的制备及表征   总被引:12,自引:0,他引:12  
在聚砜基膜上用界面聚合法制备了两种复合型纳滤膜PA01和PA02。在0.3MPa下,PA01膜对MgSO4溶液和FeCl3溶液的脱直 96.0%和78.0%,水通量分别为8.5(L.m^-2.h^-1)和7.9(L.m^-2.h^-1);PA02膜对MgSO4ipwkiyw (2.0g.L^-1)和CaCl溶液(0.5g.L^-1)的脱盐率分别为98.0%和88.8%,水通量分别为1.0(L。m^  相似文献   

9.
林进  赵汝琪 《应用科技》2000,27(6):24-25,27
研究了以固体超强酯SO4^2-/TiO2/La^3+为催化剂,乙酸和异戊醇为原料合成乙酸异戊酯,并考察了影响反应的因素。结果表明,醇酸摩尔比为1.8:1,催化剂用量为0.5g(乙酸为0.2mol的情况下),带水剂甲苯为15ml,反应时间为2.0h是最适宜的反应条件,酯化率达98.5%。display status  相似文献   

10.
在盐酸底液中,单硝酸异山梨酯在汞电极上于-0.50V和-0.88V产生两个不可逆的还原峰,以下用循环伏安法,微分脉冲极谱,常规脉冲极谱及恒电位电解等多种电化学方法研究了该体系的电地为和电极机理,两个峰的产生是由于硝酸酯的两步不可逆还原所致,利用第一峰单扫描极谱法测定了片剂中单硝酸异山梨酯的含量,线性范围为0.02-20mg.L^-1,检测下限为0.01mg.L^-1,探讨了影响灵敏度的主要因素。  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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