等环的

The production methods of glutaraldehyde,including those of addition reaction of acraldehyde , oxidation of 1,5-pentadiol,reduction of glutaryl chloride and oxidation of cyclopentene,are summarized.

综述了丙烯醛加成、 1，5 -戊二醇氧化、戊二酰氯还原和环戊烯氧化等戊二醛的合成路线和制备方法，考察了目前戊二醛的生产厂家及其在皮革鞣剂、油田注水杀菌剂和医药杀菌等领域的应用市

In this paper, after the introduction of the basic concepts and the main results on K〓 theory, relative K〓 theory and the theory of classical groups of degree 2 which is related to K〓 theory, we study the problems of the computation of K〓 for the ring of integers of quadratic imaginary fields, examples of subrings of quadratic fields which are not universal for GE〓 and generating set of the Cokernel of the canonical homomorphism from K〓 to K〓.

本文在介绍了K〓理论和相对K〓理论以及与K〓理论有关的2阶典型群的基本概念及主要成果之后，对于虚二次域代数整环的K〓群的计算，非GE〓泛的虚二次域的子环以及K〓到K〓的自然同态的余核的生成元集等问题进行了研究。

The design of teaching contents combines Logo and art. The Logo includes know Logo learning environment, basic commands practice and the procedure in assembly basic commands; the artistic course introduces the repetition principle and hue circle of color.

教学内容设计上分为Logo及艺术两部分，其中Logo包括认识Logo学习环境、基本指令操作、将基本指令组合成为程序等三项，艺术包括色相环的运用、重复原理的运用等二项。

Whereas the tin hydride is used, for preparing functional fivemembered rings ,to induced alkenyl radical translocation/ cyclization process ——oxidaton process by selective activation of a C H bond——developed by Curran et al., thiophenol, non-tin chemical, is used in this new synthetic method for preparing cyclopentane derivatives through a 1,5-hydrogen transfer/cyclization sequenceEq.

在这些目标中，发展无毒、环保试剂实施有效的自由基反应是一具有挑战性的目标。Curran等发明了用氢化锡介导的自由基易位/环化过程是一种通过C H键的选择性氧化制备功能五元环的高效的方法。

The 4-acetylenyl phenylformic acid synthesized with the method contains carboxyl and terminal alkynyl, and is a valuable synthesized used in organic chemistry and is of great prospect to be applied in biomedicine, medicine field, etc, particularly in replacing phenylacetylene which is recently widely used in the synthesis of aromatic heterocycle, such as triazole.

本发明方法合成的4-乙炔基苯甲酸结构中含有羧基和末端炔基，是有机化学中极有价值的合成"砌块"，在生物医学、医药等领域有着十分重要应用前景，特别是取代苯乙炔近年来被广泛用于三唑等芳香性杂环的合成。

By using in a sequence the eigen-decomposition,a permutation,the inverse discrete Fourier transformand a truncation on the matrix,an exact and explicit parametrization formula for Loop subdivision surfaces is proposed.

利用控制网格拓扑结构的对称性，通过将奇异点周围1-环和2-环的控制顶点进行离散Fourier变换得到分块对角阵，将其进行特征分解及排序之后，再通过离散Fourier逆变换和截断等操作得到细分矩阵的高次幂的表达式，从而得到Loop 细分曲面新的精确参数化公式

Those ions will perform stable oscillation nearby the beam orbit while their mass is larger than a critical mass. The accumulation of trapped ions nearby the beam orbit, interacting with beam, can cause the tune shift of beam, blowup of beam emittance, increase of local vacuum pressure, and can even lead to the occurrence of beam instability.

这些被俘获的离子在束流轨道附近的积累并和束流的相互作用，会引起束流振荡频率的漂移和展宽、束流发射度的增加、局部真空度的恶化等各种负效应，有时甚至会导致束流不稳定的发生，从而影响储存环的正常工作，在这种情况下采用离子清洗方法将离子清洗掉对保证储存环的长期、稳定的运行是必要的。

Advances in Research on Plants Reactions under Phosphate Starvation;2. Topics discussed in this article includes synthesis and structures of R2M24, the reactions of its metal-metal triple bond with various reagents such as nucleophiles, carbon-carbon mu.

本文对一类重要的ⅥB族金属叁键化合物R_2M_2_4(R为环戊二烯基及类环戊二烯基)近年来的研究成果进行了综述，综述重点是这类化合物的官能团M≡M参键的化学活性，全文包括R_2M_2_4的合成及结构，M≡M叁键与亲核试剂、与碳-碳重键，与氧或与金属羰基物等试剂的反应及其应用。

Topics discussed in this article includes synthesis and structures of R2M24, the reactions of its metal-metal triple bond with various reagents such as nucleophiles, carbon-carbon mu.

本文对一类重要的ⅥB族金属叁键化合物R_2M_2_4(R为环戊二烯基及类环戊二烯基)近年来的研究成果进行了综述，综述重点是这类化合物的官能团M≡M参键的化学活性，全文包括R_2M_2_4的合成及结构，M≡M叁键与亲核试剂、与碳-碳重键，与氧或与金属羰基物等试剂的反应及其应用。

Since there are some disadvantages, such as magnitudes, reference systems and difficulties in observing an asteroid during its motion in its whole orbit, etc., when the asteroid is observed simply by means of the meridian or photograph methods, a new method for observing asteroids with a lower latitude meridian circle and a CCD measuring device is proposed according to the conditions of the geographic latitude of the Yunnan Observatory which can be used to observe the whole orbit of an asteroid.

考虑到单纯用子午方法或照相方法对小行星进行观测存在着因星等、定标星系统，以及难于在小行星运行全轨道上进行观测等方面的不利因素，在本文中，根据云南天文台能观测小行星全轨道的地理纬度条件，提出利用低纬子午环与CCD测量装置相配合，并利用低纬子午环直接提供的定标星，在一个统一的基本仪器系统中，通过对小行星在全轨道上均匀分布的观测，获得高精度的小行星观测资料，以便得到更准确的星表零点改正。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。