乙烯-辛烯共聚物/淀粉共混体系的非等温结晶动力学(英文)

通过差示扫描量热仪(DSC)研究了乙烯-辛烯共聚物/淀粉共混体系的非等温结晶动力学,用Jeziorny和Ozawa方程描述了结晶动力学过程.共混物的结晶温度和结晶焓强烈依赖于淀粉含量和冷却速率.结果表明,随着冷却速率的增加,每个试样的结晶放热曲线均变宽,并向低温区移动.当温度一定高时,所有试样均具有较快的结晶速率. Jeniorzy方程可以较好地描述POE/淀粉共混物的非等温结晶模式,而Ozawa方程对于POE/淀粉共混体系不太适合.     

Synthesis and Primary Research on Antitumor Activity of Three New Panaxadiol Fatty Acid Esters

For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs,three new fatty acid ester compounds: 3β-acetoxy panaxadiol ( Ⅰ ), 3β-palmitic acid aceloxy panaxadiol ( Ⅱ ), and 3β-octadecanoic acid aceloxy panaxadiol( Ⅰ , Ⅱ , and Ⅲ ) were synthesized with panaxadiol, diacetyl oxide, palmityl chloride and stearyl chloride, and their structures were determined via MS, 13C NMR, IR, TLC, and so on. The molar yields of the three compounds are 75.14%, 79. 08%, and 72. 57%, respectively. Meanwhile, the antitumor activity of the three new panaxadiol fatty acid ester derivatives and panaxadiol was compared by using the method of MTT. Tumor cell used was Vero cell line. Positive control was 5-FU, blank was an RPMI1640 culture medium, negative control was an RPMI1640 culture medium and the solvent for drugs to be tested. Compound Ⅰ has the strongest antitumor activity followed by panaxadiol; compounds Ⅱ and Ⅲ have similar and weakest antitumor activities.Furthermore, the antitumor activities of the panaxadiol fatty acid ester derivatives show positive correlation with the concentration of the test group, but show no relationship with the molecular weight of fatty acid. The methods that are used to synthesize the three compounds with high yields and strong antitumor activities are simple and show a great potential for meeting the needs of industrial manufacture of these drugs.     

微波辐照下无皂阳离子聚(St-MMA)高分子纳米粒子的制备和表征

讨论了微波辐照下 ,以丙酮 水为分散介质 ,利用阳离子型自由基引发剂偶氮二异丁基脒盐酸盐(AIBA)引发苯乙烯 (St)和甲基丙烯酸甲酯 (MMA)共聚 ,合成出表面带正电荷的P(St MMA)共聚物纳米粒子 ,考察了丙酮用量、单体和引发剂浓度对纳米粒子粒径、粒径分布和乳液稳定性的影响 .结果表明 ,丙酮 水的体积比由 0增加到 1 2 6∶1时 ,粒子的平均水化半径从 12 2 2 1nm降低到 2 4 6 8nm ,粒径分布变宽 ,乳液抗电解质稳定性逐渐增强 ;增加引发剂和共聚单体MMA的浓度 ,粒子的水化半径逐渐减小 ,粒径分散系数增大 .     

Two New C—21 Steroidal Glycosides from Cynanchum aurichulatum

Two new C-21 steroidal glycosides, cynanauriculoside I and cynanauriculoside Ⅱ, were isolated from the roots of Cynanchum aurichulatum. Their structures were established using spectroscopic methods including one and two-dimensional NMR.     

金(Ⅲ)与杯[4]乙酯合钠(Ⅰ)超分子化合物: [Na(C60H80O12)]+[Au(SCN)4]-的合成、结构及性能

A novel super molecule [Na(C₆₀H₈₀O₁₂)]⁺[Au(SCN)₄]^- was obtained by extraction of calix[4] arene (L) for an aqueous solution containing [AuCl₄]^-, and NaCl into CH₂Cl₂. The crystal structure and properties of the title super molecule were characterized by single-crystal X-ray diffraction, IR and ¹H NMR spectra. The X-ray single crystal structure analysis shows that the crystal was Tetragonal system with space group P4/n and the unit cell parameters were as follows: a=2.880 8(18) nm, b=2.880 8(18) nm, c=2.292 4(5) nm, and final R indices [I>2σ(I)]: R₁=0.048 5, wR₂=0.106 1. CCDC: 243229.     

FTIR-ATR技术研究聚氨酯类文物保护材料的光降解

Polyurethanes are one kind of relic protection materials commonly used. During artificial photo-ageing, three polyurethanes, HDI-based polyurethane, MDI-based polyurethane and TDI-based polyurethane, have been considered to undergo UV radiation. Photochemical degradation of the polyurethanes has been monitored by means of Fourier transform infrared spectroscopy with attenuated total reflection accessory （FTIR-ATR）. It was proved that the mechanism of the photochemical degradation of polyurethanes might be the scissions of carbamate （urethane） groups and the re-reactions of radical groups formed in the scission reactions. From the experiment results HDI-based polyurethane, an aliphatic diisocyanate, could be considered to be more suitably used as relic protection materials among these three polyurethanes for its ageing products with less color.     

Ab initio study on the mechanism of reaction HNCO+NH_2

Ab initio UMP2 and UQCISD(T) calculations, with 6-311G** basis sets, were performed for the titled reactions. The results show that the reactions have two product channels: NH2+ HNCO→NH3+NCO (1) and NH2+HNCO-N2H3+CO (2), where reaction (1) is a hydrogen abstraction reaction via an H-bonded complex (HBC), lowering the energy by 32.48 kJ/mol relative to reactants. The calculated QCISD(T)//MP2(full) energy barrier is 29.04 kJ/mol, which is in excellent accordance with the experimental value of 29.09 kJ/mol. In the range of reaction temperature 2300-2700 K, transition theory rate constant for reaction (1) is 1.68 × 1011- 3.29 × 1011 mL · mol-1· s-1, which is close to the experimental one of 5.0 ×1011 mL× mol-1· s-1 or less. However, reaction (2) is a stepwise reaction proceeding via two orientation modes, cis and trans, and the energy barriers for the rate-control step at our best calculations are 92.79 kJ/mol (for cis-mode) and 147.43 kJ/mol (for trans-mode), respectively, which is much higher than     

螺[1-氯-4-l-孟氧基-5-氧杂-6-氧代双环[3·1·0]己烷-2,3'-(4'-吗啉基-5'-l-孟氧基丁内酯)]合丙酮的合成及晶体结构

利用新手性源,5-(l-孟氧基)-3-氯-2(5H)-呋喃酮4与亲核试剂吗啉通过串联不对称双Michael加成/分子内亲核取代反应合成了一般方法难以得到的含有多个手性中心的螺-环丙烷双内酯化合物C32H50O7NCl.其单晶为C32H50O7NCl(OC3H6)0.5,正交晶系, 空间群为P212121, 晶胞参数a = 17.149(3), b = 20.384(4), c = 10.831(2) , V = 3786.1(12) 3, Z = 4, Dc = 1.097 g/cm3, F(000) = 1352, μ= 0.144 mm-1; 射线类型为MoK?( = 0.71073 ?, 偏离因子R = 0.0755, wR = 0.1956, 独立衍射点3710个, 其中可观测点数2318个.分子中共有六个环, 12个手性中心, 3个六元环呈椅式构象, 两个五员内酯环呈信封式构象, 并分别与环丙烷形成[2.4]螺环和 [3.1.0] 稠环, 4个新生成的手性中心的绝对构型为C(3)(S), C(4)(S), C(5)(R), C(8)(R).     

MoCo/Y, MoNi/Y氮化物催化剂的结构和CH4+CO2重整反应性能

采用氨气还原法制备了NaY分子筛负载的MoCo/Y、MoNi／Y双组氮化物催化剂，用XRD和EXAFS方法征了样品的结构，并测定了其在CH4＋CO2重整反应中的活性，在氧化态时，MoCo/Y样品中主要存在CoMoO4和Co3O4两种物相，Mo的配位状态接近于CoMoO4，而Co的配位状态更接近于Co3O4，MoNi／Y样品中主要有NiMoO4和NiO两种物相，Mo的配位状态接近于MiMoO4，而Ni的配位状态可能是NiMoO4和NiO两种化合物中Ni配位状态的平均效果，Ni-Mo之间的朴素作用似乎比Co-Mo相对较强，在氮化态时，两种样品中Mo的配位状态较为相似，但即不同于MoO3，也不同于单组分γ－Mo2N.Co和Ni的配位状态都不同于各在氧化态下的状态，且都在相同的位置出现一个新强峰，这似乎表明MoCo和MoNi生成了结构相似的氮化物，在CH4＋CO2重整反应中，氮化态MoCO/Y和MoNi/Y的活性大大超过非负载单组分γ－Mo2N催化剂，其中MoNi/Y的活性相对更好一些，且活性随Ni含量增加而提高。     

IONIC CONDUCTIVITY OF METHYLSILOXANE TERMINATED POLYETHYLENE OXIDE WITH LITHIUM PERCHLORATE NETWORK FILMS

Complex films of crosslinked poly(methylsiloxane-co-ethylene oxide) and lithium perchlorate were prepared. These solid state polymeric electrolytes show a markedly higher ionic conductivity, and excellent flexibility. The ionic conductivity of the network films closed to 10~(-5) Scm~(-1) at room temperature. The effects of Li~+ content, species and contents of crosslinking agents, molecular weight of poly(ethylene oxide) and temperature on the ionic conductivity of the network films were also investigated.