Studies of interaction between iron (III) and intermediates of synthetic neuromelanin by means of cyclic voltammetry of Fe(CN)(3-)(6) and dopamine

Neuromelanin is a complex polymer pigment found primarily in the dopaminergic neurons of the human substantia nigra, whose composition is complex including production of dopamine auto-oxidation, glutathione and a variety of amino acid. Neuromelanin forms stable complex with iron (111). We observed that 5,6-dihydroxyindole and its ramification possessed strong ability of chelating iron (111), and they are the production of dopamine auto-oxidation under physiological pH condition. In the present Of L-Cysteine, the relative yields of electrochemical oxidation of dopamine also had strong ability of chelating iron (111). The experimental results suggest that 5,6-dihydroxyindole and 5-S-cysteineldopamine play important roles in the process of synthetic neuromelanin chelating iron (111).

PVC-尼龙6树脂应用于天然水中痕量金的价态分析

在王水介质中，ＰＶＣ－尼龙６树脂定量吸附Ａｕ（Ⅲ），而Ａｕ（Ⅰ）基本上不吸附。当存在碘离子时，Ａｕ（Ⅲ）和Ａｕ（Ⅰ）均能形成碘的络阴离子而被树脂定量吸附，从而可分别测出总金和Ａｕ（Ⅲ）的含量并计算出Ａｕ（Ⅰ）的含量。方法的检测限为１．６×１０－１１ｇ／Ｌ，样品加标回收率在８０％以上。为天然水中痕量金的价态分析提供了一个令人满意的方法。

氧化钕填充尼龙6的结晶行为

利用示差扫描量热仪（ＤＳＣ）研究了氧化钕（Ｎｄ２Ｏ３）对尼龙６（ＰＡ６）等温结晶行为的影响。结果表明，Ｎｄ２Ｏ３在ＰＡ６体系中起到了异相成核作用，提高了ＰＡ６的晶体增长速率。

THE CLEAVAGE REACTION OF THE MO-MO TRIPLE BOND - THE CRYSTAL-STRUCTURES OF MOLYBDENUM COMPLEXES [CPMO(CO)(2)(C(5)H(4)NS)], [CPMO(CO)(2)(C(9)H(6)NS)]O=PPH(3) AND [CPMO(CO)(2)(S(2)CNME(2)]

The reactions of [Cp2Mo2(CO)4] (1) with 2,2'-dipyridyl disulphide (C5H4NS-)2, 8,8'-diquinolyl disulphide (C9H6NS-)2 and tetramethyl thiuram disulphide (Me2NC(S)S-)2 in toluene solution resulted in the cleavage of the Mo-Mo triple bond to yield molybdenum complexes [CpMo(CO)2(C5H4NS)] (2), [CpMo(CO)2(C9H6NS)] (3) and [CpMo(CO)2(S2CNMe2)] (4), respectively. The molecular structures of 2, 3 . O=PPh3 and 4 were determined by X-ray diffraction studies. Crystals of 2 are monoclinic, space group P2(1)/n, with Z = 4, in a unit cell of dimensions a = 6.448(1), b = 12.616(2), c = 14.772(2) angstrom, beta = 92.85(1)-degrees. The structure was refined to R = 0.028 and R(w) = 0.039 for 1357 observed reflections. Crystals of 3 . O=PPh3 are triclinic, space group P1BAR, with Z = 2, in a unit cell of dimensions a = 11.351(3), b = 13.409(3), c = 9.895(2) angstrom, alpha = 94.59(2), beta = 90.35(2), gamma = 78.07(2)-degrees. The structure was refined to R = 0.033 and R(w) = 0.037 for 3260 observed reflections. Crystals of 4 are monoclinic, space group P2(1)/a and Z = 4 with a = 12.468(5), b = 7.637(2), c = 13.135(4) angstrom, beta = 96.62(3). The structure was refined to R = 0.032 and R(w) = 0.042 for 1698 observed reflections. Each of complexes 2-4 contains a cyclopentadienyl ligand, a cis pair of carbonyls and a chelate ligand (S,N donor or S,S donor). All the compounds have distorted square-pyramid structures.

马先蒿属6个种的核型与进化研究

分析和报道了马先蒿属（Pedicularis Linn.）分布于青藏高原东北部６个特有种的核型，并根据核型及其有关参数，分析和比较了该６种马先蒿核型的不对称性和相对进化程度。６个种的体细胞染色体数目都是２ｎ＝１６。核型分别为：绵德马先蒿P.pilostachya Maxim.，核型公式Ｋ（２ｎ）＝１６＝４ｍ＋１２ｓｍ，染色体相对长度组成２Ｌ＋６Ｍ２＋６Ｍ１＋２Ｓ，核型不对称系数Ａｓ·Ｋ＝６５．２９％，属于２Ａ型；青海马先蒿P.przewalskii Maxim.，Ｋ（２ｎ）＝１６＝８ｍ（ＳＡＴ）＋４ｓｍ＋２ｓ＋２ｔ，２Ｌ＋８Ｍ２＋２Ｍ１＋４Ｓ，Ａｓ·Ｋ＝６５．０２％，２Ｂ型；华马先蒿P.oederi Vahl.var.sinensis(Maxim.)Hurus.，K(2n)=16=12m+4sm，2L+4M2+8M1+2 S，As·K=59.89%，2B型；粗野马先蒿P.rudis Maxim.，K(2n)=16=4m+10sm+2st，4L+4M2+4M1+2 S，As·K=68.10%，2B型；甘肃马先蒿P.kansuensis Maxim. Subsp. kansuensis，K(2n)=16=6m+6sm+2st+2t，2L+6M2+6M1+2 S，As·K=68.92%，2A型；藓生马先蒿P.muscicola Maxim. K(2n)=16=8m(SAT)+8sm，2L=8M2+4M1+2S，As·K=62.64%，2B型。根据这6个种的核型和已有资料，认为该属的染色体基数x=8，极少数种有多倍体。通过对以上6种核型及进化程度的比较，该属核型变异较大，以中部着丝粒染色体为组成基础（较原始的种类，如华马先蒿和绵穗马先蒿），端部或近端部着丝粒染色体存在与否与该属内种的进化程度有关。核型不对称性所表示的进化程度似乎与花冠的演化有联系。