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1.
油菜萝卜胞质不育系恢复材料Ad-6(F4)测交二代恢复株TCF2,在MS附加5mg/L 6-BA+0.5mg/L NAA,3mg/L,6-BA+0.2mg/L NAA,3mg/L 6-BA|0.3mg/L NAA+600mg/L水解5mg/L-6-BA+0.3mg/L NAA+5mg/L AgNO3对TCF2诱导丛生芽有较好的效果。  相似文献   

2.
本研究首次观察到在水溶液中溶解有Cl^-,NO3^-,F^-,HCO3^-和SO4^-五种阴离子时,只有F^-在浓度高于4.0mg/L时会对声致发光产生影响,当在4.0mg/L ̄2.0mg/L范围内改变F^-的浓度,声致发光强度随F^-浓度的增加而下降,F^-的引入使得空化区域的低温等离子体的形成变为可以控制。  相似文献   

3.
沉淀法测定S(Ⅳ)的方法用于测定空气中的SO2。用含TRIS(羟基甲基-氨基甲烷)和叠氮钠的溶液在空气流速为15 ̄40L/h富集空气中的SO2,时间为30min。加入高氯酸、Co^2+和Mn^2+的溶液促使叠氮-Co(Ⅲ)络合物的形成(最后NH3/N3^-缓冲溶液的pH为5.2 ̄5.4),与吸收溶液中的S(Ⅳ) 成正比。用分光光度法,在365nm、标准曲线斜率为(3.07±0.03)×10L·mo  相似文献   

4.
在pH=5-12的乙醇水溶液中,Cu62+与丙酮醛双,N.N‘-缩氨基硫脲可形成1:1型络合物,其λmax=488nm,ε488=1.09×10^4L.mol^-1.Cu^2+浓度在0-5.0mg/L内服从比耳定律;若用氯仿萃取后测定,其ε488=1.77×10^5L.mol^-1cm^-2,Cu^2+浓度在0-0.50mg/L内服从比耳定律。  相似文献   

5.
珍珠花丛生芽的诱导及生根条件的研究   总被引:5,自引:0,他引:5  
诱导珍珠花(Staphylea bumalda DC)丛生芽的最佳培养基为MS基本培养基附加NAA0.2mg.L^-1和BA5MG.l^-1,无菌苗在1/2MS培养基中附加NAA1mg.L^-1、活性碳0.45g.L^-1、硫胺素1mg.L^-1、蔗糖20g.L^-1能长根形成完整植株。  相似文献   

6.
Cl-和SO2-4对厌氧废水处理的抑制阈值   总被引:4,自引:0,他引:4  
用人工配制高浓度有机废水分别研究了Cl^-和SO4^2-对厌氧生物废水处理的抑制作用和抑制阈值。在全混流厌氧恒化器和上流式厌氧污泥床(UASB)反应器中分别得到了对厌氧消化基本无抑制作用(全混流恒化器:Cl^-〈4.5g/L,SO4^2-〈1.8g/L;UASB:Cl^-〈7.2g/L,SO4^2-〈3.0g/L);轻度抑制(全混流恒化器:Cl^-=4.5 ̄6.0g/L,SO4^2-=1.8 ̄3.  相似文献   

7.
催化动力学光度法测定S^2—的研究   总被引:2,自引:0,他引:2  
依据S^2-能催化碱性品红褪色的指示反应,建立了测定微量S^2-的催化动力学地在PH9.20的硼砂缓冲介质中,室温(10℃)下,本法线性测定范围为0.03-2.00mg/L,检测下限为0.016μg/mL,除SO^2-3外,其余离子不影响测定。SO^2-3的干扰可加入甲醛除去,用本法测定了水样和模拟样品中S^2-的含量,结果令人满意。  相似文献   

8.
用c(NH4F)=0.015mol/L的NH4F和c(HCl)=0.3mol/L的LCl提土壤样品中有效磷,以钼锑抗分光光度法测定有效磷的含量。在c(H2SO4)=0.2~0.3mol/L的H2SO4和Sb^3+存在下,到与钼酸铵反应形成磷锑钼杂多酸,该杂多酸在常温下被抗坏血酸还原为磷钼蓝络合物,它的最大吸收波长于700nm处,磷量在0.1~1400μg/L内服从比尔定律,检出限为0.024μg/  相似文献   

9.
单柱离子色谱法同时测定土壤中溴和碘的研究   总被引:3,自引:0,他引:3  
本文研究了以邻苯二甲酸/三羟甲基氨基甲烷为淋洗液的单柱离子色谱法同时测定土壤中微量溴和碘离子的方法。样品采用碳酸钠-氧化镁混合熔剂半熔,热水浸提,无基体干扰。淋洗液最佳浓度为2.2mmol.L^-1,H2C8H4O4/2.0mmol.L^-1H2NC(CH2OH)3。最低检测限Br^-0.065μg/ml.I^-0.027μg/ml。相对标准偏差Br^-,1.96%,I^-3.17%,回收率Br^  相似文献   

10.
微量钒的停流流动注射-动力学光度法测定   总被引:1,自引:0,他引:1  
依据V(Ⅳ)-Cr(Ⅵ)反应对Cr(Ⅵ)-Ⅰ-氧化还原反应的诱导,以淀粉络合物为指示剂建立了一种测定微量钒的停流-诱导动力学光度法.线性范围为0~1.8mg/L,方法检测限为0.008mg/L.除Fe2+、Sb3+外,大部分共存离子不影响测定.测定了土样中钒含量,结果满意.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
20.
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   

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