APPLICATION OF THE MOMENT METHODS TO ANALYSIS OF X-RAY DIFFRACTION LINE PROFILE FOR PA1010-BMI SYSTEM

Pure X-ray diffraction profiles have been analysed for polyamide 1010 and PA1010--BMI system by means of multipeak fitting resolution of X-ray diffraction.The methods ofvariance and fourth moment have been applied to determine the particle size and strainvalues for theparacrystalline materials.The results indicated that both variance and fourthmoment of X-ray diffraction line profile yielded approximately the same values of theparticle size and the strain.The particle sizes of(100)reflection have been found todecrease with increasing BMI content,whereas the strain values increased.     

化合物库的组合技巧和组合合成

从化合物库的组合技巧和组合合成方法两个方面探讨了组合化学及其在药物开发中的应用。     

FTIR－PAS技术在卟啉类化合物中的应用（Ⅲ）──乙酰丙酮－meso－四－（对－氯代）苯基卟啉稀土配合物的红外光声光谱

研究乙酰丙酮－ｍｅｓｏ－四－（对－氯代）苯基卟啉及其Ｎｄ、Ｓｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ、Ｌｕ配合物在３６００～２２０ｃｍ－１范围内的傅立叶变换红外光声光谱，对其主要谱带进行经验归属．实验结果表明，四－（对－氯代）苯基卟啉与稀土乙酰丙酮配合物中的金属离子配位，削弱乙酰丙酮环上的Ｍ－Ｏ键伸缩振动，使该谱带向低波数方向移动．金属敏感带出现在～１５５８、～１４７４、～１４２７、～１２１９、～７９８、～７３３、～２５０ｃｍ－１．     

A New Bislabdane-type Diterpenoid from Cunninghamia lanceolata

Cunninghmia lanceolata Hook. is a traditional Chinese medicine used for thetreatment of hernia, arthritis and strangury. its chemical constituents have beenexamined]' 2' 3' '. In a previous paper we reported a bislabdane-type diterpenoidlanceolatic acid from the roots of the plant 5. Further chemical studies on this plantled to the isolation of another new bislabdane-type diterpenoid, named lanceolatin(I ).Compound I was obtained as white amorphous powder. mp 232-234 'C, [a]."-24 (c 0. 10, C…     

Bentone-34/OV-1毛细管柱的研制及其分离性能

自行研制了Bentone-34/OV-1高效石英毛细管气相色谱柱,并利用该柱分别对二甲苯、二氯苯和二氯甲苯异构体3种体系进行分析.在选用的色谱条件下,难分离物质对二甲苯和间二甲苯分离度达3;间二氯苯和对二氯苯分离度达1 3.结果表明该柱具有分离效果好,分析速度快的优点.     

Ring-opening Polymerization of e-Caprolactone Using Lanthanide Tris(4-tert-butylphenolate)s as a Single-component Initiator

The ring-opening polymerization of e-caprolactone (CL) initiated by novel single lanthanide tris(4-tert-butylphenolate)s [Ln(OTBP)3] is reported. Single-component La(OTBP)3 can effectively prepare polycaprolactone (PCL) with over 90% yield and viscosity average molecular weight about 60 x 10 under quite mild conditions: molar ratio of CL to initiator is 1000, 60 C, 2 h in toluene. Mechanism study indicates that the monomer inserts into the growing chain via the break of acyl-oxygen bond of CL.     

X-Ray Powder Diffraction Studies of Polyhydrates of Cross-Linked Tetraisoamylammonium Polyacrylates

X-ray powder diffraction studies were performed of the polyhydrates, formed at positive temperature in swelled grains of carboxylic cation-exchange resins in the form of tetraisoamylammonium (cross-linked tetraisoamylammonium polyacrylates, differing in the degree of cross-linking: 1, 2 and 3%). It was shown that the polyhydrates exist as the crystalline phase under specific conditions, determined earlier by DTA technique. Diffraction patterns of the samples, recorded at the temperature +3 ± 1 °C, indicate that the polyhydrates crystallize in hexagonal symmetry, the unit cell parameters are close to a=12.25 Å, c=12.72 Å and do not depend significantly upon the degree of cross-linking. The suppositions were made concerning the size of hydrate crystallites, formed in the swelled grains of the studied resins.This revised version was published online in July 2005 with a corrected issue number.     

苯乙烯-异戊二烯嵌段共聚物分子运动的脉冲核磁共振研究

用西德Bruke,MSL-300核磁共振谱仪研究了三个不同系列的苯乙烯-异戊二烯嵌段共聚物的固体回波谱。用PASCAL语言在谱仪提供的计算机上、用线性最小二乘法回归分析把实验曲线分解成快速和慢速两个组分,它们分别对应于嵌段共聚物中刚性相和流动相,从而给出样品两相结构的定性定量信息。     

Structure and Two-photon Excited Blue Fluorescence of an Asymmetrical Substituted Stilbene

In common fluorescence process, molecular excitation is caused by the absorption of at least a single photon with shorter wavelength. When certain laser is used as the pump source, some compounds can be excited by simultaneous absorption of at least two photons and then the emission of up-converted fluorescence may occur. This process is called two-photon excited fluorescence (TPEF)1,2. Because of several advantages of TPEF, including intrinsic high three-dimensional resolution and the p…     

手性双氨基醇-Et2Zn催化的不对称直接羟醛缩合反应

以1,3-二溴丙酮和(2'S)-(二苯基羟甲基)-四氢吡咯为原料,合成了两种新型手性氨基醇1,3-双[(2'S)-(二苯基羟甲基)-1-四氢吡咯基]丙酮(3)和1,3-双[(2'S)-(二苯基羟甲基)-1-四氢吡咯基]-2-丙醇(4),总产率分别为39%和35%.手性双氨基醇3-/4-Et2Zn可催化未修饰醛、酮的不对称直接羟醛缩合反应,对映体过量最高9%.