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101.
基于伴随表示,通过引入Jacobi-Ostrogradsky坐标,获得了Guo族约束流的Lax表示,Poisson结构和r-矩阵,最后,借助Poisson结构和r-矩阵,说明了Guo族约束 是Liouville可积的。 相似文献
102.
IntroductionTheproblemofgivendifferentialequationandseekingitsequivalentHamiltonianiansystembelongstoinverseproblemofanalyticalmechanics,andthelatterisoneofprimeproblemsinclassicalmechanics.ThefamousPoincare_CartonproblemistogettheHamiltonianianregula… 相似文献
103.
2+1-维变系数广义Kadomtsev-Petviashvili方程的相似约化 总被引:4,自引:0,他引:4
借助于MATHEMATICA软件,将直接约化法推广并应用到2+1-维变系数广义Kadomtsev-Petviashvili(VCGKP)方程,获得了VCGKP方程的若干相似约化,其中包括PainleveⅠ型、PainleveⅡ型和PainleveⅣ型的约化. 相似文献
104.
Preparation of Fe3O4@SiO2@MnO2 microspheres as an adsorbent for Th(IV) removal from aqueous solution
Zhou Weini Wang Hongqing Hou Sanying Wang Shiyv 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):253-263
Journal of Radioanalytical and Nuclear Chemistry - A magnetic nano-composites Fe3O4@SiO2@MnO2 were fabricated for efficient removal of Th(IV) from aqueous solutions, and characterized by SEM, TEM,... 相似文献
105.
本文立足于中国传统文化提出非线性学习方法, 使数学物理中国化、简单化、个性化. 从八卦的角度统一看待非线性科学中的孤子、混沌、分形和机器学习, 以诗联网引领学科之间的对话, 实现学科之间的乾坤大挪移. 相似文献
106.
This paper introduces a discrete homotopy analysis method (DHAM) to obtain approximate solutions of linear or nonlinear partial differential equations (PDEs). The DHAM can take the many advantages of the continuous homotopy analysis method. The proposed DHAM also contains the auxiliary parameter ?, which provides a simple way to adjust and control the convergence region of solution series. The convergence of the DHAM is proved under some reasonable hypotheses, which provide the theoretical basis of the DHAM for solving nonlinear problems. Several examples, including a simple diffusion equation and two-dimensional Burgers’ equations, are given to investigate the features of the DHAM. The numerical results obtained by this method have been compared with the exact solutions. It is shown that they are in good agreement with each other. 相似文献
107.
A new criterion ω2, defined as Tg/(2Tx?Tg)?Tg/Tl (wherein Tg is the glass transition temperature, Tx the onset crystallization temperature, and Tl the liquidus temperature), has been proposed to assess the glass-forming ability (GFA) of bulk metallic glasses (BMGs) based on the classical crystallization theory and the crystallization resistance. The analysis indicates that the factors Tg/(2Tx?Tg) and Tg/Tl could reflect the crystallization resistance and liquid phase stability of metallic glasses, respectively. From the available experimental data in literatures, the new criterion ω2 has a better correlation with the GFA of metallic glasses than all other existing criteria such as Trg(=Tg/Tl), ΔTx(=Tx?Tg), γ(=Tx/(Tg+Tl)), ΔTrg(=(Tx ? Tg)/(Tl ? Tg)), α(=Tx/Tl), β(=Tx/Tg + Tg/Tl), δ(=Tx/(Tl ? Tg)), φ(=Trg(ΔTx/Tg)0.143), γm(=(2Tx ? Tg)/Tl), β(=Tx × Tg/(Tl ? Tx)2) and ξ(=ΔTx/Tx+Tg/Tl). It has also been demonstrated that this ω2 parameter is a simple and efficient guideline for exploring new BMG formers. 相似文献
108.
Guanjun Liu Chengsheng Wang Hongqing Zhu Shijia Chen Xiao-yan Wu 《Journal of Dispersion Science and Technology》2017,38(5):699-703
As a function of temperature in aqueous solutions, the adsorption and aggregation of N,N’-bis (tetradecyl dimethyl)-1,2-dibromide-ethanediyl ammonium salt (GS14-2-14) and N,N’-bis (hexadecyl dimethyl)-1,2-dibromide-ethanediyl ammonium salt (GS16-2-16), were researched with drop-volume technique and conductometry, respectively. The results of surface tension measurements, which were analyzed by originally developed thermodynamic equations, illustrate that GS14-2-14 has a better surface activity and arranges more tightly in the adsorbed film than GS16-2-16. The data of conductivity were used to find critical micelle concentration (cmc) and counterion binding degree of micelle (β). Thermodynamic parameters of micellization were also obtained from the temperature dependence of cmc values. From the study, it is discovered that the micellization process is spontaneous and exothermic in nature and it is mainly driven by entropy. 相似文献
109.
We report on a highly sensitive chemiluminescent (CL) biosensor for the sequenc-specific detection of DNA using a novel bio barcode DNA probe modified with gold nanoparticles that were covered with a dendrimer. The modified probe is composed of gold nanoparticles, a dendrimer, the CL reagent, and the DNA. The capture probe DNA was immobilized on magnetic beads covered with gold. It first hybridizes with the target DNA and then with one terminal end of the signal DNA on the barcoded DNA probe. CL was generated by adding H2O2 and Co(II) ions as the catalyst. The immobilization of dendrimer onto the gold nanoparticles can significantly enhance sensitivity and gives a detection limit of 6 fmol L-1 of target DNA. Graphical Abstract
A sensitive chemiluminescent biosensor for the sequenc-specific detection of DNA using a novel bio barcode DNA probe modified with gold nanoparticle that were covered with a dendrimer was reported. The immobilization of dendrimer onto the gold nanoparticles enhances sensitivity and gives a detection limit of 6 fM of target DNA. 相似文献
110.