二聚

The catalyst system for polyisocyanates has high reality and prompts to generate thiourea dione accounting for large proportion of polyisocyanates.

本发明所提供的异氰酸酯低聚用催化剂体系，具有高活性并且还促使生成占制成的多异氰酸酯中相当比例的脲二酮。

Its steps include these:(1) purification of WPA;(2) neutralization reaction between purified WPA and sodium carbonate for the salt mixture of disodium hydrogen phosphate and monometallic sodium orthophosphate;(3) adjustment of the mixture's neutralizing degree with additive acid or alkali;(4) quick separation of crystal with additive organic solvent under continue stir;(5) polymerization of crystal under the high temperature for the high quality product of STPP.

其步骤为：(1)湿法磷酸净化；(2)净化后的磷酸与碳酸钠中和反应生成磷酸一氢钠和磷酸二氢钠混合盐溶液；(3)用酸、碱调节确定该混合盐溶液的中和度；(4)加入有机溶剂，通过不断地搅拌使晶体快速析出；(5)晶体经高温聚合，生成高品质的三聚磷酸钠。

It's obviously that the polyethylene glycol 1000 as disperser can improve the disperstiveness of BST powder in water.

使用聚乙二醇1000作为分散剂，可以使BST粉体的ζ电位由-9.61改变为-31.46，大大改善BST粉体在水中的分散性。

Since most of the large molecules containing phosphorus element have double bonds, it is necessary to consider the special structures of double bonds in order to deal with these large systems more accurately. So, based on density functional theory and electronegativity equalization principle, applying a general atom-bond electronegativity equalization method , using separated program, through regression and least-squares optimization , the parameters of atoms and bonds in molecules are determined . By these parameters , the charge distributions and the energy of some molecules containing phosphorus element, especial the fragment of DNA, RNA, are calculated . The results are quite good.

由于这些含磷生物大分子体系都含有双键，为了明确的处理双键，进而更准确的解释带有双键和共轭双键的含磷生物大分子结构与性质的关系，我们以密度泛函理论~([1-4])和电负性均衡原理~([5-9])为基础，应用和开发原子-键电负性均衡方法中的σπ模型，利用最小二乘法，拟合确定了一些分子（含碳、氮、氧、氢以及磷等原子）的各种类型原子及化学键区域的参数，并利用上述参数计算了一些多聚核苷酸的电荷分布以及分子的总能量，进行了讨论，得到的结果可以和从头算相媲美。

Experiments and application situation on determination of dysprosium by fluorescence analysis and derivative spectrum analysis method are reviewed.

对近10a来的用荧光法和导数光谱法测定镝的研究及应用进行了综合报道。研究了在聚乙二醇2000 硫酸铵铝试剂双水相体系中，铝试剂作萃取剂，对镧、镨、镝的萃取行为。

Moreover, the size of nanorods changes with the concentration of the precursor SnCl4. We also fabricate dysprosium hydroxide by means of the similar method.

我们利用相同的路线制备出了Dy3纳米管，合成过程中，聚乙二醇充当了模板剂，反应在180°C水热条件下完成。

To evaluate the salt tolerance, the salt tolerance of 93 accessions of wild emmer from Israel was studied prilimarily with water culture method .

野生二粒小麦与普通小麦的A、B染色体组在聚类图中可以大致被分为两类，二者之间的遗传相似系数不高。

Every three month for 20 years this little hand of healers met at the Walton Hotel behind locked doors and engaged in unknown emprise lasting till dawn.

二十年来，这一小撮医生，每隔三个月，就聚在华尔饭店开一次会，直到黎明，不知其做些什么。

0 Of polyamidoamine has been synthesized by a divergent method with ethylenediamine as core.

采用发散合成法，合成了以乙二胺为核的1.0代树枝状大分子聚酰胺-胺(PAMAM1.0)，用静态法测定了树枝状大分子在高硅溶液中对胶体硅的阻垢性能。

As the result of using Euclidean norm metric, the performance of traditional FCM clustering algorithm is subject to the structure of sample patterns in feature space.

一是针对SAR图象，提出了基于混合偏移Rayleigh分布假设的最小误差算法；二是针对低质量图象，提出了基于散射图SEM估计的MAP聚类算法。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。