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1.
研究了次黄嘌呤在铜电极上的电化学行为。实验发现,以1.96×10^-3 ̄4×10^-4mol·L^-1NaOH作支持电解质时,在-0.25 ̄-0.40V的电位范围内有一灵敏的阴极峰,它是吸附于铜电极表面的Hxa与Cu^+络合物的溶出伏安峰,在选择的实验条件下,峰高与Hxa的浓度在1.46×10^-6 ̄2×10^-3mol·L^-1范围内呈良好的线性关系,最低检测限为5.6×10^-8mol·L^-  相似文献   

2.
茂钛络合物,以纳米NaH为助催化剂催化苯乙烯氢化,初速率为3.7×10^3-8.3×10^3mol/(mol.min)(H2/Ti),催化效率为6.4×10^3-18.5×10^3mol/mol(H2/Ti),均高于文献的其他2茂钛催化体系,考察了不同温度对催化反应的影响,反应温度在275-315K时,活化能为20.3kJ/mol,与催化体系活性高一致。  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.
以热流分析为基础,估算了Ni原子分数分别为53%和72%的NiAl金属间化合物快速凝固过程中的速率,研究了合金比热,熔化潜热及结晶温度间隔等对冷却速率的影响。结果发现,NiAl金属间化合物快速凝固过程中的冷却速率为2.56×10^4-8.02×10^5K/s之间。快速凝固开始后的冷却速率将有所下降,下降幅度和熔化潜热及结晶温度间隔的大小有关。  相似文献   

5.
几种含硫有机化合物与铜的络合物的极谱行为研究   总被引:1,自引:0,他引:1  
高胱氨酸、6-巯基嘌呤和硫尿嘧啶均能与铜离子作用而在汞电极上产生两个吸附波、在柠檬酸钠溶液中,高胱氨酸与铜的络合物在-0.06V处产生的阳极化波较为灵敏,其检测限为2×10^-8mol/L高胱氨酸,线性范围为8×10-6~1×10^-5mol/L.6-巯基嘌呤和硫尿嘧啶在乙二胺介质中与铜产生的络合物波较好,前者在-0.83V处和后者在-0.44V处的阴极波较适合于分析,它们的检测限分别为8×10^  相似文献   

6.
研究了一种以丁二酮肟(C4H8N2O2,DMG)为修饰剂的碳糊化学修饰电极(CME)。该电极在pH=8.8的NH3-NH4Cl缓冲溶液中,对Ni2+浓度的负对数有线性电位响应。线性范围是5.0×10-7~1.0×10-3mol/L。电极修饰简单、性能稳定,每修饰一次可稳定测试10个标准系列。对钢铁试样中的微量Ni进行了测定,效果良好  相似文献   

7.
用间接方法研究了胶束中化学反应的近似处理方法,推导出胶束溶液中反应的表现速率常数k与胶束浓度「M」的关系式,并将其应用于SOD模拟物的研究。在25℃,0.8Ec(Cc为临界胶束浓度)CTAB体系中Cu(Thr)2催化O^.-2歧化反应的表观速率常数为8.37×10^8mol^-1·L·s^-1,与脉冲辐解法所得结果9.25×10^8mol^-1·L·s^-1比较接近,说明这种近似处理方法是可行的。  相似文献   

8.
以石墨电极为基体制成碳糊电极,研究了马钱子碱在该电极上的测定方法,在0.01mol·L^-1H2SO4底液中,选择阳极电位为0.35V,峰电流与马钱子碱的浓度在1.0×10^-7-1.0×10^-4mol·L^-1范围内呈良好的线性关系,该法的检测下限为5.0×10^-8mol·L^-1,回收范围为95.8-105.9%中变量的取值和相对标准偏 3.3%。本方法准确、快速、简便。  相似文献   

9.
研究了温度和应变速率对常规铸造和部分凝固铸造Zn-20%Al金合的半固态压缩形变的影响规律。试验温度和应变速率范围分别为380~430℃和2.1×10^-1×10^-4S^-1。试验结果表明,金属在半固态时的形变抗力比固态时大幅度降低;部分凝固铸造合金的形变能力优于常规铸造合金;在高温(430℃)、低应变速率(8,.4×10^-4S^-1)条件下,常规铸造合金也能获得较好的极限塑性和低的变形抗力…  相似文献   

10.
在pH为6.3的六次甲基四胺-盐酸介质中,铜(Ⅱ)-O-NPF-CTMAB络合物的最大吸收波长为595nm,摩尔吸光系数值ε为1.25×10^5L·mol^-1·cm^-1。铜浓度在0-7μg/25ml8范围内服从比耳定律,用本法测定了铝合金和天然水中微量铜。  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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