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1.
设f(z)和g(z)是两个非常数的亚纯函数,a(z)和b(z)(b(?)a~(k),k为非负整数)是关于f(z)和g(z)的小函数,并且6(a)=S(a,f) 6(a,g)>1,如果∞是f(z)和g(z)的CM分担值,b是f~(k)(z)和g~(k)(z)的CM分担值,则或者f~(k)(z)≡g~(k)(z)或者f~(k)(z)=(a~(k))(z)-b(z))e~(h(z)) a~(k))(z)和g~(z)=(a~(k)(z)-b(z))e~(-h(z)) a~(k)(z)成立,其中h(z)是整函数。  相似文献   

2.
几种苯甲酸族化合物对菜青虫多酚氧化酶的抑制作用   总被引:1,自引:0,他引:1  
以菜青虫五龄幼虫为材料,分离提取多酚氧化酶,研究对醛基苯甲酸(a)、对甲氧基苯甲酸(b)、对异丙基苯甲酸(c)、对环已基苯甲酸(d)、对氟苯甲酸(e)、对氯苯甲酸(f)和对溴苯甲酸(g)等苯甲酸族化合物,对该酶催化L-多巴(L-DOPA)氧化活力的影响.测定(a),(b),(c),(d)和(f)抑制作用的IC50分别为10.63、12.22、1.75、2.10和6.64 mmol/L,而(e)和(g)则没有明显的抑制效果.研究上述效应物的抑制作用动力学,结果表明:(a)、(c)和(f)对酶的作用表现为竞争性抑制,其抑制常数分别为6.74、1.08和3.94 mmol/L;(b)和(d)对酶的抑制作用表现为非竞争性类型,其抑制常数分别为13.11和2.21 mmol/L.  相似文献   

3.
选用石英砂和载铁石英砂两种介质模拟环境介质, 以大肠杆菌C3000 为代表细菌, 考察细菌对Pb(Ⅱ) 和Cr(Ⅵ)迁移行为的影响。研究发现, Pb(Ⅱ)和Cr(Ⅵ)在载铁石英砂中迁移的阻滞系数(分别为4.793 和 1.212)分别大于在石英砂中的阻滞系数(1.145 和0.427), 表明Pb(Ⅱ)和Cr(Ⅵ)在载铁石英砂中的迁移能力低于其在石英砂中的迁移。在石英砂中, Pb(Ⅱ)和Cr(Ⅵ)在无细菌时迁移的阻滞系数(分别为1.145 和0.427)与有细菌时迁移的阻滞系数(1.230 和0.369)相近, 表明Pb(Ⅱ)和Cr(Ⅵ)的迁移不受共存细菌的影响。在载铁石英砂中, Pb(Ⅱ)在有细菌时迁移的阻滞系数(6.360)明显大于其在无细菌时的阻滞系数(4.793), 而Cr(Ⅵ)在有细菌时迁移的阻滞系数(1.212)与其在无细菌时的阻滞系数(1.037)相近, 表明细菌的存在会抑制Pb(Ⅱ)的迁移, 而对Cr(Ⅵ)的迁移不产生影响。研究结果可为预测重金属在土壤地下水中的迁移行为提供理论依据。  相似文献   

4.
本文初步研究了厦门港微量金属的间隙水化学,在含S(Ⅱ)间隙水中,用Berner成岩数学模式估算了Fe(Ⅲ)去除反应的速率常数,用热力学方法计算了Fe(Ⅱ)、Fe(Ⅲ)、Pb(Ⅲ)、Cd(Ⅲ)、Cu(Ⅰ)、Cu(Ⅱ)、Zn(Ⅲ)、游离态S(Ⅱ)各无机形态的平衡浓度,结果表明:Cu(Ⅰ)、Cd(Ⅱ)在沉积物和间隙水中的主要无机形态是Cu_2S、CuS_4S_5~(3-)和CdS(greeno-ckite)、Cd(HS)2,间隙水中Fe(Ⅱ)和游离态S(Ⅱ)主要以Fe~(2+)和HS~-形式存在。  相似文献   

5.
研究了罗丹明B-NaCl-丙醇体系萃取汞的新方法.探讨了罗丹明B的浓度、NaCl的浓度、丙醇的浓度和酸度等对Hg(Ⅱ)萃取的影响,确定了萃取分离Hg(Ⅱ)的最佳条件,并讨论了Hg(Ⅱ)的萃取机理.当溶液中罗丹明B、NaCl和丙醇的浓度分别为0.27g/L、160g/L和30%(V/V)时,Hg(Ⅱ)的萃取率达到98.0%以上,实现了Hg(Ⅱ)与Pb(Ⅱ)、Zn(Ⅱ)、Ir(Ⅳ)、Ni(Ⅱ)、Ag(Ⅰ)、Rh(Ⅲ)、Cu(Ⅱ)、Cr(III)、Mg(Ⅱ)、Fe(Ⅲ)、Al(Ⅲ)和Co(Ⅱ)离子定量分离.  相似文献   

6.
双核钨羰基-亚硝基化合物W2(NO)2(CO)n(n=8,7)在BP86和MPW1PW91理论水平下优化出9个相对稳定的异构体。得到的W2(NO)2(CO)8和W2(NO)2(CO)7基态分别具有D4d和C1的对称性,均含有2个端亚硝基。比较W2(NO)2(CO)n(n=8,7)与其等电子体Re2(CO)n(n=10,9),发现W2(NO)2(CO)n(n=8,7)的低能构型和前人预测的Re2(CO)n+2的低能构型类似。  相似文献   

7.
采用BP86和MPW1PW91两种密度泛函理论方法对双核金属钌羰基-亚硝基配位化合物Ru2(NO)2(CO)n(n=8,7,6,5)进行了量子化学理论计算,优化后得到了19个单态和三态异构体,讨论了它们的结构和键的性质。得到的Ru2(NO)2(CO)8,Ru2(NO)2(CO)7,Ru2(NO)2(CO)6和Ru2(NO)2(CO)5的基态分别是C2v,C1,C2v和C1构型的单态。将Ru2(NO)2(CO)n(n=7,6,5)与同族铁的配合物Fe2(NO)2(CO)n(n=7,6,5)进行比较,发现二者的稳定构型特点不一致。  相似文献   

8.
目的 主要刻画对称算子空间上的2个映射M:J(H)→K(H)和M*:K(H)→J(H)是可加的,其中J(H)和K(H)分别表示H上的J-对称算子全体和K-对称算子全体.方法 利用M和M*的性质以及对称算子分块的性质进行证明.结果 与结论证明了若映射M:J(H)→K(H)和M*:K(H)→ J(H)满足{M(AM*(B)C+CM*(B)A)=M(A)BM(C)+M(C)BM(A),M*(BM(A)D+DM(A)B)=M*(B)AM*(D)+M*(D)AM*(B)且M和M*是满射,则M和M*是可加的.  相似文献   

9.
以长根菇菌丝体为材料,测定其对Pb(Ⅱ)和Cd(Ⅱ)的富集能力,以及不同浓度的Pb(Ⅱ)和Cd(Ⅱ)对菌丝体超氧化物歧化酶(SOD)和过氧化氢酶(CAT)酶活的影响,研究发现:低浓度Pb(Ⅱ)(100mg/L)明显刺激长根菇菌丝体的生长,而高浓度的Pb(Ⅱ)和Cd(Ⅱ)则抑制其生长;Pb(Ⅱ)和Cd(Ⅱ)的浓度越大,菌丝体对其富集能力越强,其最大富集量可分别达1.2132× 104 mg/kg(Pb(Ⅱ))和1.99872×103 mg/kg(Cd(Ⅱ)).此外,研究还发现,Pb(Ⅱ)和Cd(Ⅱ)可提高菌丝抗氧化酶的活性,其CAT酶活可分别提高至1.131 U/g(Pb(Ⅱ),100mg/L)和2.263 U/g(Cd(Ⅱ),1 mg/L);其SOD酶活可分别提高至13.976 U/g(Pb(Ⅱ),200mg/L)和14.668 U/g(Cd(Ⅱ),2 mg/L).  相似文献   

10.
设f(z)和g(z)是整函数且f(f)=g(g),本文讨论了f(z)和g(z)的级型间的关系,且对几类特殊的函数完全确定了f(z)和g(z)间的关系,从而补充了Urabe(4)中的内容。  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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