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1.
合成了6个模型化合物4-HO-4’-X-N-(苯亚甲基)苯胺,经~1H NMR和~(13)C NMR进行了分子结构确认.测定了化合物在6种溶剂中的紫外吸收.探讨了取代基和溶剂对其紫外吸收光谱最大吸收波长对应能量ν_(max)的影响.结果表明,基团X对ν_(max)的影响,由取代基基态极性参数σp和激发态取代基参数σ_(CC)~(ex)共同决定;溶剂对ν_(max)的影响,由溶剂在水/正辛醇中分配系数的对数log P和溶剂显色效应参数ET(30)共同表达.此外,二甲亚砜对目标化合物还存在特殊的溶剂效应.  相似文献   

2.
λKν是完全多重图.如果λKν的边集可以划分成一个p2-因子和若干个p3-因子的并,则称λKν存在{p2*,p3}-因子分解.文章主要研究完全多重图λKν的{p2*,p3}-因子分解的充分必要条件为:(1)λ≡1(mod 4),ν≡6(mod 12)或(2)λ≡3(mod 4),ν≡0(mod 12).  相似文献   

3.
利用线性代数知识讨论非负矩阵特征值的估计,简化了如下定理的证明:对于一个非负随机矩阵A的不同于1的特征值λ(A),有|λ(A)|≤1/2maxμ.ν∑i=1^n|αμi-αvi|≤1  相似文献   

4.
通过对所合成的9个可溶性酞菁衍生物在13种不同性质溶剂中吸收光谱的研究,发现其最大吸收波长的波数ν与f(n,ε)具有良好的线性相关性,表明化合物λmax的位移变化主要由与溶剂折射率n相关的Bayliss函数项所决定,且与溶剂的介电常数ε有关;忽略酞菁分子之间的相互作用(即聚集的影响)以及溶剂的配位能力,是引起模型线性相关性偏差的主要原因.  相似文献   

5.
采用硅胶柱色谱、葡聚糖凝胶以及反相高效液相色谱法等对川党参的乙酸乙酯和石油醚部位进行分离纯化,并通过1H NMR和13C NMR等波谱技术进行结构鉴定.利用Sybyl X 2.1.1软件,以Total score值为评价标准,评价川党参化学成分与磷酸二酯酶4D2(PDE4D2)的结合作用.利用Pymol和Discovery Studio 2017 R2 Client软件分析PDE4D2与化合物之间的相互作用力.结果从乙酸乙酯和石油醚部位分离出12个化合物,分别鉴定为mangnostellin D(1)、(7S,8S)-3-methoxy-3’,7-epoxy-8,4’-oxyneoligna-4,9,9,’-triol(2)、isolariciresinol(3)、curcasinlignan B(4)、(4E,12Z)-threo-tetradeca-4,12-diene-8,10-diyne-1,6,7,14-tetraol(5)、(-)-(7R,8S,7’E)-3’,4-dihydroxy-3-methoxy-8,4’-oxyneoli...  相似文献   

6.
设函数f(z)=z+a_2z~2+a_3z~3+…属于K类(单位圆盘D内凸象函数)或S类(D内单叶函数)。对于全体实数λ,μ和ν,本文讨论D内函数类(λz)/(1-μa_2z-νa_3z~2)。给出单叶条件及其象区域。并对K中所有函数f(z),绐出z/2(?)(λz)/(1-μa_2z-νa_3z~2)(?)f(z)的必要条件和(λz)/(1-μa_2z-νa_3z~2)(?)f(z)的充分条件。对S中所有函数f(z),给出z/4(?)(λz)/(1-μa_2z-νa_3z~2)(?)f(z)的必要条件及(λz)/(1-μa_2z-νa_3z~2)(?)f(z)的充分条件。  相似文献   

7.
以量子化学半经验AM1方法优化几何构型为基础,应用INDO/ CI方法对几种D-π-A型二氰基三维苯多烯及其脂环化合物的垂直跃迁能进行了计算,同时应用完全态求和(SOS)公式计算了二阶非线性光学(NLO)系数β.讨论了体系的共轭性、烯链链长变化及烯链脂环化对共轭体系结构和电子光谱的影响.结果表明:随着共轭链长度增加共轭程度增大,体系β值增大,λmax红移;烯链的脂环化使β值变小,而λmax蓝移.  相似文献   

8.
以二硫代乙二酰胺、ω一溴代苯乙酮为起始原料,合成了4,4'-二苯基-2,2'-双噻唑.m.p.216.9℃-217.1℃,收率57.5%.IR,νmax(cm-1):3111(Ar-H),3060(Ph-H),1597,1558,1541,1508,1474,1443(苯环骨架,噻唑环骨架振动),939,742,692(苯环单取代)、后经磺化,中和生成4,4'-二苯基-2,2'-双噻唑-5,5'-二磺酸二钠.m.p.>300℃,收率44%.IR,νmax(cm-1):1236,1184,1126,1047(R-SO3-).1H NMR,δ(ppm):7.63,7.56,7.51(苯H).  相似文献   

9.
以量子化学半经验AM1方法优化几何构型为基础,应用INDO/CI方法对几种具有三维结构的三氰呋喃苯多烯及其脂环化化合物进行电子光谱计算,同时应用完全态求和(SOS)公式计算二阶非线性光学(NLO)系数β.探讨了共轭烯链的长度变化及脂环化对共轭体系电子光谱和β的影响.结果表明,随着共轭链长度增加共轭程度越高,体系β值增大,而λmax红移;烯链的脂环化使β值变小,而λmax变化不大,多烯的脂环化对体系的电子光谱和NLO性质影响不大.  相似文献   

10.
以γ-氯丙基三甲氧基硅烷与对二甲胺基肉桂酸为原料,通过酯化反应合成了对二甲胺基肉桂酰氧基丙基三甲氧基硅烷,利用IR、~1H NMR、~(13)C NMR对其结构进行了表征,并对其紫外吸收性能进行了研究,紫外吸收区域为305~400 nm,最大吸收波长λ_(max)为361.6 nm,最大摩尔吸光系数ε_(max)为1.94×10~4.研究结果表明,该化合物是一种较好的新型的反应性UVA紫外线吸收剂.玻璃涂层试验表明,对于5 mm普通硅酸盐玻璃,当涂层中γ-(对二甲胺基肉桂酰氧基)丙基三甲氧基硅烷的含量达到0.8 g/m~2时,涂层玻璃的紫外线平均透光率仅有0.01.  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.
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   

15.
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   

16.
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   

17.
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   

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.
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   

20.
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   

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