THE SCHWARZIAN DERIVATIVE IN SEVERAL COMPLEX VARIABLES(II)

ＴＨＥＳＣＨＷＡＲＺＩＡＮＤＥＲＩＶＡＴＩＶＥＩＮＳＥＶＥＲＡＬＣＯＭＰＬＥＸＶＡＲＩＡＢＬＥＳ（ＩＩ）ＧＯＮＧＳＨＥＮＧＹＵＱＩＨＵＡＮＧＺＨＥＮＧＸＵＥＡＮＭａｎｕｓｃｒｉｐｔｒｅｃｅｉｖｅｄＡｕｇｕｓｔ３０，１９９６．Ｄｅ...     

Dimensional Properties of Fractional Brownian Motion

Let B^α = {B^α（t）,t E R^N} be an （N,d）-fractional Brownian motion with Hurst index α∈ （0, 1）. By applying the strong local nondeterminism of B^α, we prove certain forms of uniform Hausdorff dimension results for the images of B^α when N 〉 αd. Our results extend those of Kaufman for one-dimensional Brownian motion.     

高职院校中技能教学的探讨

本文论述高职教育中的技能训练与科技进步及科研之间的关系。     

叠层连续开口圆柱壳的精确解

抛弃任何有关位移和应力模式的假设，引入δ-函数，对正变异性连续开口圆柱壳建立状态方程．给出薄的、中厚的和强厚的叠层连续开口圆柱壳静力问题的统一的精确解．数值结果和SAPS解进行了对比．     

Isolation and Structure Elucidation of Nortriterpenoids from Schisandra rubriflora

Seven new highly oxygenated nortriterpenoids, rubriflorins D–J ( 1 – 7 ), were isolated from the leaves and stems of Schisandra rubriflora, and their structures were elucidated on the basis of extensive analysis of spectroscopic data. These new compounds feature the opening of ring A compared with related known nortriterpenoids isolated from the genus Schisandra and showed weak activity against HIV‐1.     

HPLC法测定阿奇霉素葡萄糖注射液中阿奇霉素的含量

利用高效液相色谱法，以VP-ODS型色谱柱，乙腈-异丙醇-水-氨水（60：25：15：0.1)为流动相，于210nm波长处测定了阿奇霉素葡萄糖注射液中阿奇霉素葡萄糖注射液中阿奇霉素的含量。阿奇霉素的浓度在0.75-1.75mg/mL线性关系良好，线性方程的A=881910.4c-16208.2，相关系数r=0.9999。阿奇霉素的平均回收率为99.59%，测定结果的相对标准偏差为1.31%。     

Impoverishment of Soil Nutrients in Gully Erosion Areas in Yuanmou Basin

The impoverishment of soil nutrients of nine gully head areas in Yuanmou Basin is assessed through an integrated evaluation method established on the basis of Fuzzy mathematics and multivariate mathematical theory. Results show that soil erosion of gully erosion area in Yuanmou basin has resulted in severe impoverishment of soil nutrients. All gully head areas are at high leves of impoverishment except for one at middle. By probing into and analyzing the mechanism of impoverishment of soil nutrients, we find that soil erosion has led to impoverishment of soil nutrients in a way of compacting soil, heightening position of obstacle horizon, and reducing the content of organic matter, as well as the direct loss of nutrient elements. Finally, this paper points out that soil and water conservation arming at the prevention of soil erosion is the most effective way against impoverishment of soil nutrients in Yuanmou basin.     

Ethylene–propylene copolymerization with bis(β‐enaminoketonato) titanium complexes activated with modified methylaluminoxane

Ethylene–propylene copolymerization, using [(Ph)NC(R₂)CHC(R₁)O]₂TiCl₂ (R₁ = CF₃, Ph, or t‐Bu; R₂ = CH₃ or CF₃) titanium complexes activated with modified methylaluminoxane as a cocatalyst, was investigated. High‐molecular‐weight ethylene–propylene copolymers with relatively narrow molecular weight distributions and a broad range of chemical compositions were obtained. Substituents R₁ and R₂ influenced the copolymerization behavior, including the copolymerization activity, methylene sequence distribution, molecular weight, and polydispersity. With small steric hindrance at R₁ and R₂, one complex (R₁ = CF₃; R₂ = CH₃) displayed high catalytic activity and produced copolymers with high propylene incorporation but low molecular weight. The microstructures of the copolymers were analyzed with ¹³C NMR to determine the methylene sequence distribution and number‐average sequence lengths of uninterrupted methylene carbons. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5846–5854, 2006     

Synthesis and light emitting properties of polyacetylenes having pendent fluorene groups

Five novel fluorene‐containing polymers, poly[(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA1 ), poly[(1‐pentyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene) ( PFA2 ), poly[1‐decyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA3 ), poly[1‐phenyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA4 ), and poly[1‐(3,4‐difluorophenyl)‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA5 ) were synthesized by the polymerization of the corresponding fluorene‐substituted acetylenic monomers ( M1–M5), using WCl₆, MoCl_5, and TaCl₅ as catalysts and n‐Bu₄Sn as a cocatalyst. The synthesized polymers were thermally stable and readily soluble in common organic solvents. The degradation temperatures for a 5% weight loss of the polymers were ∼352–503 °C under nitrogen. PFA1–PFA5 show emission peaks from 402 to 590 nm. Besides, their electroluminescent properties were studied in heterostructure light‐emitting diodes (LEDs), using PFA2–PFA5 as an emitting layer. The PFA5 device revealed an orange‐red emission peak at 602 nm with a maximum luminescence of 923 cd/m² at 8 V. A device with the ITO/PEDOT/ a mixture of PFA2 (98 wt %) and PFA5 (2 wt %)/Ca/Al showed near white emission. Its maximum luminance and current efficiency are 450 cd/m² at 15 V and 1.3 cd/A, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 519–531, 2006     

Highly soluble and optically transparent poly (ether imide)s based on 2,6‐ or 2,7‐bis(3,4‐dicarboxyphenoxy)naphthalene dianhydride and aromatic bis(ether amine)s bearing trifluoromethyl groups

Two series of novel fluorinated poly(ether imide)s (coded IIIA and IIIB ) were prepared from 2,6‐bis(3,4‐dicarboxyphenoxy)naphthalene dianhydride and 2,7‐bis(3,4‐dicarboxyphenoxy)naphthalene dianhydride, respectively, with various trifluoromethyl‐substituted aromatic bis(ether amine)s by a standard two‐step process with thermal or chemical imidization of the poly(amic acid) precursors. These fluorinated poly(ether imide)s showed good solubility in many organic solvents and could be solution‐cast into transparent, flexible, and tough films. These films were nearly colorless, with an ultraviolet–visible absorption edge of 364–386 nm. They also showed good thermal stability with glass‐transition temperatures of 221–298 °C, 10% weight loss temperatures in excess of 489 °C, and char yields at 800 °C in nitrogen greater than 50%. The 2,7‐substituted IIIB series also showed better solubility and higher transparency than the isomeric 2,6‐substituted IIIA series. In comparison with nonfluorinated poly (ether imide)s, the fluorinated IIIA and IIIB series showed better solubility, higher transparency, and lower dielectric constants and water absorption. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5909–5922, 2006