DETERMINATION OF DEGREE OF CRYSTALLINITY OF NYLON 1212 BY WIDE-ANGLE X-RAY DIFFRACTION

Based on the X-ray scattering intensity theory and using the approximate expression for the atomic scattering factor, the correction factors for three crystalline peaks and an amorphous peak of Nylon 1212 were calculated and the formula of degree of crystallinity of Nylon 1212 was derived by a graphic multipeak resolution method. The degree of crystallinity calculated from the WAXD method is compatible with those obtained by density and calorimetry methods.     

地下水水质评价中相关性分析方法的应用

在对四川省红层丘陵区浅层地下水水质评价的基础上,应用SPSS和Excel以及Surfer 3种方法分析了样品中的元素含量和进行了相关性分析。结果表明,SPSS和Surfer 8.0联用,能较好地阐明污染物的相关性和元素分布的特征,更直观地作出宜宾市屏山县浅层地下水水质现状评价。     

STUDIES ON PREPARATION OF INACTIVATED VACCINES FROM CELL CULTURES OF MINK ENTERITIS VIRUS (MEV) AND THEIR IMMUNITY

In this paper, superhigh reproductive rate strains of MEV with titre more than HA8192* or TCID50 log9.7 10 have been achieved both by cultivation in cell lines with different susceptibility to MEV and by isolating and identifying in field by the author. The systematic tests proved that S18 and L12 strains of MEV are the best strains for vaccine preparation. In this study, the best means for the tissue cultivation of MEV and the most advanced technological process for the production and detection of serum-free cell-cultured MEV fluids with super-high HA titre in batches in large quantities have been established for the first time. Optimum conditions for MEV inactivation were determined, and safe and effective inactivated vaccines with mineral oil or A1(OH)3 gel adjuvant were successfully prepared with serum-free cell-cultured MEV fluids. Both vaccines with different adjuvants can be manufactured in batches in large quantities and have been widely used all over China since 1986. The change laws of the imm     

Effect of pressure on oxygen enrichment of liquid crystalline cellulose ether membranes at elevated temperature

Cholesteric liquid crystalline triheptyl cellulose (THC)/ethyl cellulose binary blend membranes were prepared and the effect of pressure on their oxygen enrichment at elevated temperature was investigated using a constant pressure-variable volume method. The oxygen enrichment increased with the increase of transmembrane pressure difference or with slight increase of the THC content in the blend membranes. The oxygen concentration through the membranes increased linearly with decreasing pressure ratio. Air was directly separated through a 17 m-thick THC/EC(1.5/98.5) membrane to prepare an oxygen-enriched air containing 39.5% oxygen at the flux of 6.99×10^–4 cm³ (STP)/s.cm² at the pressure difference of 0.43 MPa and 85 °C.     

Non-solvated aluminum hydride. Crystallization from diethyl ether-benzene solutions

Crystallization of non-solvated aluminum hydride from a diethyl ether-benzene mixed solvent was studied. The desolvation of AlH₃·(Et₂O)_x etherate in solution and the crystallization of α-AlH₃ during polythermal heating of the solution occur only in the presence of ≥10 wt.% LiAlH₄. The process is multistage, and the crystallization begins with the formation of the AlH₃·0.25Et₂O solvate, which recrystallizes in the solid phase into γ-AlH₃ and then α-AlH₃. Four crystalline modifications of aluminum hydride were characterized by X-ray diffraction and electron microscopy. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1259–1265, July, 2007.     

化学模式识别技术评价中药厚朴质量的研究

本文对不同产地和市售的二十四种厚朴药材及饮片的萃取液进行了高效液相色谱、气相色谱及紫外光谱分析;对所得数据用主成分分析进行分类,概括出不同样品化学成分的异同,认为大叶木兰可做为厚朴的代用品,而在陕西安康购得的样品不应做厚朴使用,后者经生药学鉴定为厚朴伪品凹叶木兰。化学模式识别技术可为寻找药材的代用品、评价中药质量及鉴定伪劣药材提供依据。     

Sonochemical synthesis of mass single-crystal PbS nanobelts

Based on sonochemical technique, large-scale PbS nanobelts are successfully synthesized in the mixed solution of PbCl₂ and Na₂S₂O₃. These nanobelts are characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), selected area electronic diffraction, energy dispersive X-ray spectroscopy, and high-resolution TEM. The as-synthesized PbS nanobelts have width of about 80 nm, length up to several millimeters, and width-to-thickness ratio of about 5. In addition, the growth mechanism of PbS nanobelts is suggested.     

Studies on the thermotropic liquid crystalline polymer. VII. Synthesis and properties of photocrosslinkable poly(ether-ester) containing cinnamic group

A series of semi-aromatic poly(ether-ester)s containing cinnamic group was prepared from 4,4′-diacrylic acid-α,ω-phenoxyalkanes with diols in the presence of diphenylchlorophosphate (DPCP) and pyridine as a catalyst and solvent. The phase behavior of these polymers was studied by differential scanning calorimetry (DSC), optical polarizing microscopy equipped with a heating stage, and wide-angle x-ray diffraction (WAXD). All of the poly(ether-ester)s, except P3 , show nematic or smectic thermotropic liquid crystalline behaviour under optical polarizing microscopic observation. These polymers can undergo photocrosslinking reaction upon heating, as examined by IR, solubility, and DSC analysis. © 1993 John Wiley & Sons, Inc.     

聚砜-聚芳酯嵌段共聚物的合成及其液晶性

本文以对笨二甲酰氯(TC)、对苯二酚(HQ)及不同分子量的端羟基聚砜低聚物(PSF)为原料,通过熔融缩聚法制得了一系列含有聚砜间隔段的三组分嵌段共聚酯。对产物用偏光显微镜下的双折射、搅动乳光和X-光衍射等手段研究了其液晶行为。分别以分子量为1.05×10~3和2.05×10~3的PSF为原料,所得其聚酯出现液晶性所需介晶单元的最小用量各为30和50mol％,若以双酚A(BPA)或双酚S(BPS)残基单元代替PSF基元计算,则为8.3和9.9mol％。