反相高效液相色谱法制备银杏叶中聚戊烯醇同系物单体

利用制备高效液相色谱法从银杏叶中分离制备了聚戊烯醇同系物单体。在HiQ sil C18柱上,以异丙醇-甲醇-正己烷-水(体积比为50∶25∶15∶4)为流动相,流速10 mL/min,采用等度洗脱方式,制备了8种化合物,经紫外光谱、红外光谱及质谱分析,确认它们分别为C70,C75,C80,C85,C90,C95,C100和C105聚戊烯醇,其中主要成分为C85及C90聚戊烯醇。高效液相色谱分析表明,制备的C75C105聚戊烯醇化合物的纯度均在96%(质量分数)以上。在该色谱条件下,各色谱峰达到了基线分离,     

A borel-weil-bott approach to representations of sl q (2, ℂ)

We use a quite concrete and simple realization of sl _q (2, ) involving finite difference operators. We interpret them as derivations (in the noncommutative sense) on a suitable graded algebra, which gives rise to the noncommutative scheme ¹ II ^1* as the counterpart of the standard ¹ = Sl(2, )/B.     

Measurement of angular distribution of M shell fluorescent X-rays excited by 5·95 keV photons in thorium

The differential cross-sections for the emission of M shell fluorescent X-rays from Th by 5·95 keV photons at eight angles ranging from 50° to 120° have been measured. The differential cross-section is found to decrease with increase in the emission angle showing anisotropic spatial distribution of M shell fluorescent X-rays. The present results contradict the predictions of the calculations of Cooper and Zare [1] that the atomic inner shell vacancy states produced in photoionization are not aligned but confirm those of Fluggeet al [2] and Scofield [3] that the vacancy states withJ > 1/2 are aligned. The integral M shell fluorescent emission cross sections have been determined from the measured angular distribution coefficients and compared with theoretical integral cross-sections calculated by using theoretical values of M subshell photoionization cross-sections, fluorescence yields and coster kronig transition probabilities available in literature. The experimental and theoretical values of integral crosssections show a reasonable agreement.     

大麦叶肉和叶肉原生质体间若干性状的比较

和叶肉相比，叶肉原生质体的K含量下降，Fe, Zn, Mn, Cu等元素的含量则显著升高，游离ABA水平显著较高;碱性过氧化物酶活性明显下降.以上事实表明，叶肉细胞的脱壁措施会使细胞原生质体的生理、、生化状况产生显著变化.     

关于Fujita类方程组解的有界性和Blow up的一些结论

对Fujita类方程组解的整体存在性和如何在有限时间内发生Blow up现象的研究,具有实际意义.M.Escobedo等人对其二元情形曾做过研究,即在[1]中对非线性项单一如v~(?)或u~(?)的Cauchy问题进行了讨论,本文意在上述基础上作些推广:修改非线性项如u~(?)v~(?)或u~qv~n情形,利用上、下解的方法,证明了在一定条件下,推广后的Cauchy问题亦有[1]中指出的类似的结果.     

Integrable Hamiltonian systems related to the Hilbert–Schmidt ideal

By the application of the coinduction method as well as the Magri method to the ideal of real Hilbert–Schmidt operators we construct the hierarchies of integrable Hamiltonian systems on Banach Lie–Poisson spaces which consist of such types of operators. We also discuss their algebraic and analytic properties and solve them in dimensions, N=2,3,4$N=2,3,4$.     

Experimental intensity patterns obtained from a 2D shearing interferometer with adaptable sensitivity

The interferometric intensity patterns from a 2D shearing interferometer are shown and discussed. The intensity patterns can be obtained in two different approaches incorporating differential and extended wavefront controlled displacements. The reliable directional sensitivity of this interferometer allows the optimization of the measurement parameters to estimate the wavefront of the intensity patterns by regularization techniques.     

Fracture mechanisms of Hg0.8Cd0.2Te induced by pulsed TEA-CO2 laser

The fracture mechanisms of Hg_0.8Cd_0.2Te induced by pulsed TEA-CO₂ laser have been investigated theoretically and experimentally in this paper. The Hg_0.8Cd_0.2Te target was irradiated by a TEA-CO₂ laser with wavelength of 10.6 μm and spike width of 240 ns in an ambient atmosphere. The evident cracks can be found on the surface of the target from the scanning electron microscopy (SEM) photos, indicating that the severe breaks happened during the experiment. Theoretical analysis has also been carried out and the results show that the fracture of Hg_0.8Cd_0.2Te is mainly induced by thermal stresses, although there are three forces (thermal stress, evaporation wave and laser-supported detonation (LSD) wave) exerted on the target surface during the process.     

Inhomogeneous quantum groups and their quantized universal enveloping algebras

The quantum group IGL _q (N), the inhomogenization of GL _q (N), is formulated with -matrices. Theq-deformed universal enveloping algebra is constructed as the algebra of regular functionals in this formulation and contains the partial derivatives of the covariant differential calculus on the quantum space.     

Temperature dependence of the Ho L2‐edge XMCD spectra of Ho6Fe23

An X‐ray magnetic circular dichroism (XMCD) study performed at the Ho L_2,3‐edges in Ho₆Fe₂₃ as a function of temperature is presented. It is demonstrated that the anomalous temperature dependence of the Ho L₂‐edge XMCD signal is due to the magnetic contribution of Fe atoms. By contrast, the Ho L₃‐edge XMCD directly reflects the temperature dependence of the Ho magnetic moment. By combining the XMCD at both Ho L₂‐ and L₃‐edges, the possibility of determining the temperature dependence of the Fe magnetic moment is demonstrated. Then, both μ_Ho(T) and μ_Fe(T) have been determined by tuning only the absorption L‐edges of Ho. This result opens new possibilities of applying XMCD at these absorption edges to obtain quantitative element‐specific magnetic information that is not directly obtained by other experimental tools.