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1.
In this paper,the principle of complex source point and various analyt-ical methods of complex ray are summarized.Some possible applications ofcomplex ray method to underwater acoustics are proposed,including complexray analysis of directional acoustic fields,complex ray simulation of directivityof acoustic radiator arrays,complex ray transformation of acoustic fields fromnear zone to far zone,as wel1 as theoretical prediction of sonar target strengthby complex ray method.  相似文献   

2.
用JASCO J-20C自动记录旋光仪测定了β-cyclodextrindien,β-cyclodextrindien-Cu^2+配合物,β-cyclodextrindien-苯甲酸配合物及β-cyclodextrindien-Cu^2+-苯甲酸三元配合物的园二色谱,并利用Cu^2+配合物及苯甲酸的轨道能级顺序对谱带进行了归属。并根据Cu^2+配合物的结构特征及KAJART扇形规则确定了配合物的结  相似文献   

3.
We study complex Lagrangian submanifolds of a compact hyper-Kähler manifold and prove two results: (a) that an involution of a hyper-Kähler manifold which is antiholomorphic with respect to one complex structure and which acts non-trivially on the corresponding symplectic form always has a fixed point locus which is complex Lagrangian with respect to one of the other complex structures, and (b) there exist Lagrangian submanifolds which are complex with respect to one complex structure and are not the fixed point locus of any involution which is anti-holomorphic with respect to one of the other complex structures.  相似文献   

4.
5.
复杂系统重构   总被引:2,自引:0,他引:2       下载免费PDF全文
远离平衡态的开放复杂系统遍及自然、社会和技术领域,是复杂性科学的主要研究对象.通过与外界的能量和物质交换,复杂系统通过自组织形成了多种多样的内在结构、秩序和规律,对认识和预测复杂系统提出了艰巨的挑战.随着实验技术的提高和科技的进步,反映和体现各种复杂系统机理的数据呈指数增长,为研究复杂系统提供了新的机遇.通过系统行为表象数据,揭示复杂系统结构和动力学属于物理领域的反问题,是认识复杂系统的基础,是预测系统状态演化的前提,对于实现系统状态的调控必不可少.然而,复杂系统的多样性和复杂性给解决这一反问题造成了极大的困难.因此,需要开阔思路,借助多学科的交叉与融合,充分挖掘数据中隐藏的知识和深层次机理.本文综述了近年来复杂系统,特别是复杂结构重构和推断方面的研究成果,希望能够启发复杂系统反问题方面的创新.同时,也希望呼吁各领域学者都能关注复杂系统反问题,推动自然、社会、经济、生物、科技领域的交叉与融合,解决大家共同面对的科学问题.  相似文献   

6.
采用紫外分光光度法测定了Cu(Ⅱ)和L-组氨酸二元配合物的组成及Cu(Ⅱ)与L-组氨酸和泮托拉唑三元配合物组成,研究了配合物的紫外吸收光谱性质,考察了溶液pH对配合物稳定性的影响。Cu(Ⅱ)和L-组氨酸二元配合物的组成比为1∶2,Cu(Ⅱ)与L-组氨酸和泮托拉唑三元配合物组成比为1∶1∶1,碱性条件有利于配合物的生成。该结果应用于高效液相色谱法分离泮托拉唑对映体,分离度为1.4。  相似文献   

7.
吴亚波  邵颖  董鹏 《物理学报》2004,53(9):2846-2851
通过引入二重复对称度规张量,建立了一种二重复对称引力理论. 从一个二重实的作用量出发,导出了静态球对称二重复度规的具体表达式. 该理论扩展了Moffat结果,不仅自然地得到了双曲复对称引力理 论,而且把著名的Schwarzschild解作为特殊情况包含在其中,并且在线性化的弱场近似下自动摆脱了Moffat理论中存在的负 能鬼态问题. 进一步,通过将二重复坐标推广到满足二重非对易关系以及将Moyal星积二重 化,由此构造出二重非交换复对称引力场作用量. 关键词: 非交换几何 复对称度规 非对易坐标 引力场作用量  相似文献   

8.
Research on the interaction of cr(III) complex of genistein with DNA   总被引:1,自引:0,他引:1  
The interaction of the Cr(III) complex of genistein (GEN-Cr) with calf thymus DNA (ctDNA) in Tris (pH 7.2) buffer was investigated using UV spectra, DNA melting, fluorescence spectra and viscosity. From the absorption titration experiment, no obvious red shift was found, but the notable hypochromicities were observed. When C(DNA)/C(GEN-Cr) = 3, the pi-pi* transitions of the complex at 272 nm showed a decrease in intensity of 29.1%, which indicated that there was remarkable intercalation between complex and DNA base pairs, involving a strong pi-stacking interacting between them. The binding constant for the complex was K = 1.9 x 10(5) mol x L(-1). From the melting curves of ctDNA in the absence and presence of the complex, the melting temperature of ctDNA was found to increase by 5.5 degrees C from 74 to 79.5 degrees C, owing to the increased stability of the helix in the presence of the complex that was intercalated into the double helix. The complex could emit weak luminescence in Tris buffer. The emission intensity of the complex at 340 nm increased steadily with the addition of ctDNA. The result suggested that the complex got into a hydrophobic environment inside the DNA and avoided the effect of solvent water molecules. The strong interaction of the complex and ctDNA also resulted in greatly enhanced intensity of the resonance light scattering spectra. The emission intensity of DNA-EB system at 600 nm decreased remarkably with increasing the complex concentration, which indicated that the complex could be intercalated into DNA and replace EB from the DNA-EB system. According to the classical Stern-Volmer equation, the quenching plots at 25 and 37 degrees C both appeared approximately linear. These results showed that there was one predominant quenching style in this process. Viscosity experiments were carried out by an Ubbelodhe viscometer at 20.0 (+/- 0.1) degrees C. The relative viscosity of ctDNA increased steadily with the increased in the complex. The result clearly showed that the complex could be intercalated between DNA base pairs, causing an extension of the helix, and thus increased the viscosity of DNA. The results above indicated that there is a relatively strong interaction between the GEN-Cr complex and ctDNA, and the complex could bind ctDNA mainly by intercalation. The research suggested that the GEN-Cr complex may be a promising candidate for anticancer, which deserves further research.  相似文献   

9.
Study of complex huygens' principle   总被引:1,自引:0,他引:1  
Complex Huygens' principle provides an exact base for the simulation of wave propagation through a complex medium by complex ray. In this article, presented is the general formula of complex Huygens' principle, i. e. the complex point source representation of three-dimensional wave propagation, and the analytic formula of the strength of complex point source is derived here for the special case that wave sources are enclosed in a sphere.  相似文献   

10.
An alternative to the representation of complex relativity by self‐dual complex 2‐forms on the spacetime manifold is presented by assuming that the bundle of real 2‐forms is given an almost‐complex structure. From this, one can define a complex orthogonal structure on the bundle of 2‐forms, which results in a more direct representation of the complex orthogonal group in three complex dimensions. The geometrical foundations of general relativity are then presented in terms of the bundle of oriented complex orthogonal 3‐frames on the bundle of 2‐forms in a manner that essentially parallels their construction in terms of self‐dual complex 2‐forms. It is shown that one can still discuss the Debever‐Penrose classification of the Riemannian curvature tensor in terms of the representation presented here.  相似文献   

11.
Quercetin-iron (II) complex was synthesized and characterized by elemental analysis, ultraviolet-visible spectrophotometry, fourier transform infrared spectroscopy, mass spectrometry, proton nuclear magnetic resonance spectroscopy, thermogravimetry and differential scanning calorimetry, scanning electron micrography and molar conductivity. The low molar conductivity value investigates the non-electrolyte nature of the complex. The elemental analysis and other physical and spectroscopic methods reveal the 1:2 stoichiometric ratio (metal:ligand) of the complex. Antioxidant study of the quercetin and its metal complex against 2, 2-di-phenyl-1-picryl hydrazyl radical showed that the complex has much more radical scavenging activity than free quercetin. The interaction of quercetin-iron (II) complex with DNA was determined using ultraviolet visible spectra, fluorescence spectra and agarose gel electrophoresis. The results showed that quercetin-iron (II) complex can intercalate moderately with DNA, quench a strong intercalator ethidium bromide and compete for the intercalative binding sites. The complex showed significant cleavage of pBR 322 DNA from supercoiled form to nicked circular form and these cleavage effects were dose-dependent. Moreover, the mechanism of DNA cleavage indicated that it was an oxidative cleavage pathway. These results revealed the potential nuclease activity of complex to cleave DNA. In addition, antibacterial activity of complex on E.coli and S. aureus was also investigated. The results showed that complex has higher antibacterial activity than ligand.  相似文献   

12.
Through introducing the concept of complex current and resetting cross-coupling term, this paper proposes a novel complex permanent magnet synchronous motor system and analyzes its properties. Based on a complex permanent magnet synchronous motor system, we design controllers and achieve lag synchronizations both in real part and imaginary part with backstepping method. In our study, we take complex current, time delay, and structure of complex system into consideration. Numerical simulation results demonstrate the validity of controllers.  相似文献   

13.
Chaotic systems demonstrate complex behaviour in their state variables and their parameters, which generate some challenges and consequences. This paper presents a new synchronisation scheme based on integral sliding mode control (ISMC) method on a class of complex chaotic systems with complex unknown parameters. Synchronisation between corresponding states of a class of complex chaotic systems and also convergence of the errors of the system parameters to zero point are studied. The designed feedback control vector and complex unknown parameter vector are analytically achieved based on the Lyapunov stability theory. Moreover, the effectiveness of the proposed methodology is verified by synchronisation of the Chen complex system and the Lorenz complex systems as the leader and the follower chaotic systems, respectively. In conclusion, some numerical simulations related to the synchronisation methodology is given to illustrate the effectiveness of the theoretical discussions.  相似文献   

14.
To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes.  相似文献   

15.
16.
We prove that a set of nonsingular free solutions of Maxwell's equations forms a representation of the group obtained by analytic continuation of the Poincaré group to complex values of the group parameters, and that a set of singular solutions forms a representation of the group obtained by analytic continuation of the conformal group to complex values of the group parameters. These results are obtained by constructing a theory governing 2 × 2 complex matrix fields defined for complex values of position and time; the equations of this theory are invarient with respect to complex Poincaré transformations and complex conformal transformations, but the set of nonsingular solutions is in one-to-one correspondence with a set of nonsingular solutions of Maxwell's equations, and a similar correspondence exists for the singular solutions. Certain collections of solutions of Maxwell's equations for the field of a current form representations of these complex groups if both magnetic and electric currents are permitted, in which case complex transformations provide a natural connection between electric and magnetic charge. A class of complex transformations also yield natural relations between sources moving slower than light and sources moving faster than light.  相似文献   

17.
The complex of o-phenylenediamine (o-PDA) and benzoin (BN) was synthesized adopting solid state reaction by mixing of their melt together followed by chilling. The phase diagram study shows the formation of a complex in 1:1 molar ratio with congruent melting point and two eutectics lying on either side of complex. The formation of complex was confirmed using the FTIR, NMR, mass spectroscopy, powder XRD and DSC studies. The optical properties of the parent component, their complex and few other compositions nearby the complex were studied using absorption and laser luminescence techniques. The significantly higher green/yellow emission was noted with newly synthesized complex as compared to that of their parents as well as other compositions of o- PDA and BN.  相似文献   

18.
合成了新的配合物EuL3phen,[HL=4,4,4-三氟-1-(4’-间三联苯基)-1,3-丁二酮,phen=邻菲咯啉]。采用元素分析,红外光谱,质谱对该配合物的结构进行了表征。该化合物在半导体InGaN芯片发出的近紫外光激发下,发出铕(Ⅲ)离子5D0—7FJ(J=0~4)跃迁特征红光,最大发射峰位于613 nm,发光量子效率为13%。配合物寿命为470μs,寿命曲线很好地和单指数衰减拟合曲线相吻合。配合物热稳定性达到220℃,满足制备LED器件的要求。将配合物EuL3phen和半导体395 nm发射InGaN芯片组合,成功地制备了红色发光二极管。发光二极管的色坐标、发光效率、配合物和硅胶质量比相关,在配合物和硅胶质量比为1∶25时,器件色坐标为x=0.64,y=0.35,光效为0.89 lm.W-1。该配合物是充当制作白光LED用的潜在的红色发光组分。  相似文献   

19.
从20世纪中叶至今,复杂系统研究迅速发展,成为了引人注目并具有广泛应用的新领域.复杂系统要么具有结构的复杂性,要么具有演化的复杂性,在多数情况下二者兼具.不同于传统物理学通常处理的规则介质,许多复杂系统具有复杂结构,近年来受到极大关注的复杂网络结构就是其中最典型的代表.同时复杂系统也可表现为演化行为的多样性和复杂性.即便系统结构并不复杂,系统中的非线性相互作用可能产生复杂的演化行为,包括:形形色色的不稳定性;丰富的斑图动力学;各种各样的自组织、涌现及进化行为等等.物理学从一开始就深深进入了复杂系统研究领域,其中统计物理无疑是研究和理解复杂系统最主要的工具.  相似文献   

20.
在乙醇和水的混合溶液中,制备出钕、邻菲口罗啉和荧光素的三元络合物。通过对生成物的红外和拉曼光谱的综合分析,发现当反应比例为邻菲口罗啉:钕离子:荧光素为1:2:3时,三者能有效络合。光谱分析的结果表明:荧光素的羧基以单齿形式与金属离子配合。依据实验和理论分析对实验中的相关现象做出了解释。  相似文献   

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