Polymerization of 1,3-butadiene with VO(P-204)(2) and VO(P-507)(2) activated by alkylaluminum

The oxovanadium phosphonates (VO(P-204)(2) and VO(P-507)(2)) activated by various alkylaluminums (AlR3, R = Et, i-Bu, n-Oct; HAIR(2), R = Et, i-Bu) were examined in butadiene (Bd) polymerization. Both VO(P-204)(2) and VO(P-507)(2) showed higher activity than those of classical vanadium-based catalysts (e.g. VOCl3, V(acac)(3)). Among the examined catalysts, the VO(P-204)(2)/Al(Oct)(3) system (I) revealed the highest catalytic activity, giving the poly(Bd) bearing M-n of 3.76 x 10(4) g/mol, and M-w/M-n ratio of 2.9, when the [Al]/[V] molar ratio was 4.0 at 40 degrees C. The polymerization rate for I is of the first order with respect to the concentration of monomer. High thermal stability of I was found, since a fairly good catalytic activity was achieved even at 70 degrees C (polymer yield > 33%); the M-n value and M-w/M-n, ratio were independent of polymerization temperature in the range of 40-70 degrees C. By IR and DSC, the poly(Bd)s obtained had high 1,2-unit content (> 65%) with atactic configuration. The 1,2-unit content of the polymers obtained by I was nearly unchanged, regardless of variation of reaction conditions, i.e. [Al]/[V], ageing time, and reaction temperature, indicating the high stability of stereospecificity of the active sites.

萃取分离稀土元素及计算机模拟计算的研究

为了改变稀土萃取工艺单靠人工模拟实验确定的落后状况和满足生产自动化的需要，近十多年来，国内外许多国家相继开展了稀土萃取数学模型的研究。但大部分工作侧重于两相平衡分配模型方面，所提出的相平衡分配模型中，用来进行串级计算的尚不多见，进行串级计算的也大多采取逐级计算法。对于P_(507)的萃取体系的数学模型的研究及用矩阵法进行串级模拟计算，国外尚未见报导。本论文在单级实验的基础上，对15个单一稀土的RECl_3-HCl-P_(507)体系及部分二元稀土的RECl_3-HCl-P_(507)和Re(NO_3)_3-HNO_3-P_(507)体系进行了萃取平衡的讨论，求出了上述体系中，单个稀土的表现浓度平衡常数；为了串级模拟计算的需要，提出了一个形式简单、较为通用的相平衡模型，用FORTRAN语言编写了该模型的回归程序，通过回归上述体系的单级实验数据，得到了各模型的系数。进行了(Sm-Gd)(NO_3)_3-HNO_3-P_(507)体系的分馏萃取实验，和中科院化工冶金所协作，对该体系的串级模拟计算进行研究。所用串级模型把两相稀土浓度、酸度、萃取剂浓度作为变量，由以上的相平衡模型和各级稀土、酸、萃取剂的物料稀算式构成的大型非线性方程组，采用改进牛顿法求解该方程组进行计算，用FORTRAN语言编写了计算程序，计算结果和实验结果较为一致。在此基础上，独立地继续进行研究，对串级模型进行了很大的改动，改进后的串级模型把酸度、萃取剂浓度这些变量隐含在相平衡模型中，去掉了原来串级模型的酸、萃取剂的物料稀算式。和原来串级模型相比，所含的变量及方程数均减少了2N个，大大减少了占用计算机的存贮单元，提高计算收敛速度。对计算方法作了扩大迭代方向，导找最优松弛因子，采用更为合理的保证解的笔挺理意义的限制等改进，使解的收敛稳定性得到了改善。根据以上的改进用FORTRAN语言编写了新的计算程序，计算结果和实验结果吻合很好，在拟合精度，迭代次数各方面都比用原来串级模型要好得多。此外，进行了改变串级条件的模拟计算，所得结果符合萃取规律的变化。对（Ho-Er)(NO_3)_3-HNO_3-P(507)进行了2个不同工艺条件的分馏萃取实验，模拟计算值和实验值相当吻合，该体系的改变工艺条件的计算，也得到了与萃取变化规律一致的计算结果。对于文献报导的P_(204)萃取体系的分馏萃取，也同样进行了模拟计算，计算值和实验值的吻合程度也相当令人满意。通过以上不同串级体系的模拟计算，说明了所提出的相平衡模型适用于串级模拟计算；秘诀进后的串级模型及计算方法更为可靠；证明了计算机辅助实验及工艺设计的可能性。为达到这个目标打下了基础。对环烷酸分离钇的萃取体系进行了合成料及龙南稀土料的分馏萃取实验，取得了出口水相钇的纯度>97%，有机相出口非钇稀土的纯度>94%的结果。根据该体系的实际情况，简化了串级模型，提出了一种处理多元稀土体系的模拟计算方法，用FORTRAN语言编写了逐级计算程序，计算结果和实验结果有一致的趋势，但具体数值差别较大，说明该简化的串级模型及计算方法均有不够完善之处，有待深入研究。提出了一种新的萃取方式，它具有三个物料出口，可同时把若干个稀土元素分成难、中、萃三组，经试探实验初步肯定了该萃取方式的实用性。若能将之用于工厂生产上，将会带来很大的经济效益，故值得进一步研究和推广应用。

含水层介质对氯酚类污染物的吸附-解吸特性

为探讨含水层介质对氯酚类污染物的吸附规律,以吉林市含水层介质--砂土为实验材料,采用批量吸附实验方法分别研究了2,4-二氯酚、2,4,6-三氯酚及五氯酚单独存在和共存条件下在砂土上的吸附-解吸行为,并对pH、离子强度对吸附过程的影响进行了探讨。结果表明,砂土对三种氯酚的吸附-解吸符合Freundlieh等温模型,吸附常数Kd分别为5.659、2.507和2.104,解吸常数分别为22.642、8.222和4.488;吸附反应符合二级吸附速率动力学方程,吸附速率常数K分别为0.4851kg·mg-1·h-1、0.0299kg·mg-1·h-1和0.1225kg·mg-1·h-1。氯酚在砂土上的吸附机理以疏水分配和配位体交换为主。在实验范围值内,吸附量随pH增加而减小,增加离子强度可以明显加强氯酚在砂土上的吸附.

P_（507）萃淋树脂分离—火花源质谱法定量分析高纯Nd_（2）O_3中痕量稀土元素

本采用萃取色谱法，以Ｐ５０７萃淋树脂为固定相，以ＨＣｌ－ＮＨ４Ｃｌ体系为淋洗液，研究了高纯Ｎｄ２Ｏ３（９９．９９９％～９９．９９９９％）中稀土杂质与Ｎｄ基体的分离方法。选择螯合剂－活性碳柱富集淋洗液中痕量稀土，采用火花源质谱法分析，测定下限０．０１μｇ／ｇ。

有机磷农药在水生态系中生物净化机理研究——2.CTP-02降解对硝基酚的特性和动力学

从鸭儿湖氧化塘中分离出具有分解对硝基酚能力的细菌Pseudomonas sp.,代号CTP-02。在实验室条件下,细菌培养物降解对硝基酚的速度与时间之间的动力学方程为dc/dt=-K_1t-K_2,细菌降解对硝基酚的最适温度为35℃,最适pH为7.5。CTP-02菌降解对硝基酚过程中首先发生脱硝基作用。

Microcystin-RR-induced accumulation of reactive oxygen species and alteration of antioxidant systems in tobacco BY-2 cells

Microcystins are cyclic heptapeptide hepatoxins produced by cyanobacteria. It has been shown that microcystins have adverse effects on animals and on plants as well. Previous researches also indicated that microcystins were capable of inducing oxidative damage in animals both in vivo and in vitro. In this study, tobacco BY-2 suspension cell line was applied to examine the effects of microcystin-RR on plant cells. Cell viability and five biochemical parameters including reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GPX) and peroxide dismutase (POD) were investigated when cells were exposed to 50 mg/L microcystin-RR. Results showed that microcystin-RR evoked decline of the cell viability to approximately 80% after treating for 144 h. ROS levels, POD and GPX activities of the treated cells were gradually increased with a time dependent manner. Changes of SOD and CAT activities were also detected in BY-2 cells. After 168 h recovery, ROS contents, POD, GPX and CAT activities returned to normal levels. These results suggest that the microcystin-RR can cause the increase of ROS contents in plant cells and these changes led to oxidant stress, at the same time, the plant cells would improve their antioxidant abilities to combat mirocystin-RR induced oxidative injury. (c) 2005 Elsevier Ltd. All rights reserved.

Synthesis, electrochemistry and fluorescence of four new Ru(phen)(3)(2+) derivatives

Four typical LB monolayer film materials, Ru(phen)(3)(2+) complexes with one ligand attached to different long chain alkyl amides, were designed and synthesized. Their chemical structures were identified by the techniques of FT-IR, H-1 NMR and ESI-MS. Also, UV-Vis, electrochemistry and fluorescence of these complexes are reported.

Studies on organolanthanide complexes .58. Syntheses of 1,1'-(3-oxa-pentamethylene)dicyclopentadienyl divalent organolanthanides (Ln=Sm, Yb) and X-ray molecular structure of O(CH2CH2C5H4)(2)Yb(DME)

The compounds O(CH2CH2C5H4)(2)Ln(THF)(2) [Ln = Sm(1), Yb(2)] were synthesized by the reduction of O(CH2CH2C5H4)(2)LnCl with sodium metal in tetrahydrofuran (THF) at room temperature. Recrystallization of 2 from dimethoxyethane (DME) produced the single-crystal O(CH2CH2C5H4)(2)Yb(DME) (3) whose structure has been determined by an X-ray diffraction study. The crystals are orthorhombic, space group Pcab, with a = 14.168(4), b = 13.541(6), c = 19.314(8) Angstrom, Z = 8, D-calc. = 1.66 g cm(-3).

2-乙基己基膦酸单(2-乙基己基)酯树脂色层分离电感耦合等离子体原子发射光谱法测定钢中微量稀土元素

本文采用2-乙基己基膦酸单(2-乙基己基)酯(P-507)树脂,使微量稀土元素与钢中的基体元素,铁、钛、钒和钼分离,以 3.0 mol/L盐酸溶液洗脱P-507色层柱上的稀土元素,采用电感耦合等离子体原子光谱法(ICP-AES)同时测定了钢中La、Ce、Pr、Nd、Sm、Y和 Gd 7种微量稀土元素.试样的标准加入回收率99.3％～108％;相对标准偏差小于5％.

P_（507）萃淋树脂分离－火花源质谱法测定高纯Er_2O_3中痕量稀土杂质

本文采用萃取色谱法以Ｐ５０７萃淋树脂为固定相，以ＨＣｌ－ＮＨ４Ｃｌ体系为淋洗液，研究了高纯Ｅｒ２Ｏ３（９９．９９９％～９９．９９９９％）中稀土杂质和Ｅｒ基体的分离方法，并选择了富集方法和火花源质谱测定条件，达到了纯度为９９．９９９９％的超纯Ｅｒ２Ｏ３的分析要求。

P_(507)萃取重稀土元素

研究了P_(507)从HNO_3体系和HCl体系萃取重稀土Er、Tm、Yb、Lu的规律。从HNO_3体系中萃取,不论是单一组份或者多元混合组份,很快达到平衡。但从HCl体系中萃取,平衡缓慢,萃取单一稀土时温度、水相稀土浓度和酸度对平衡时间都有明显影响,萃取多元混合稀土时即使是在稀土浓度较高而酸度较低的情况下萃取平衡亦是相当缓慢的。HCl体系中Cl增加对平衡时间无明显影响,而加入少量NO_3~-离子不论是单一或者多元混合稀土体系,萃取平衡时间大大缩短。