A preliminary phylogenetic analysis of Metapenaeopsis (Decapoda : Penaeidae) based on mitochondrial dna sequences of selected species from the Indo-West Pacific

Phylogenetic relationships within Metapenaeopsis remain largely unknown. The modern revision of the genus suggests that the shape of the petasma, followed by the presence of a stidulating organ, are the most important distinguishing taxonomic features. In the present study, phylogenetic relationships were studied among seven Metapenaeopsis species from the Indo-West Pacific based on partial sequences of mitochondrial 16S rRNA and cytochrome c oxidase I (COI) genes. Mean sequence divergence was 6.4% for 16S and 15.8% for COI. A strikingly large nucleotide distance (10.0% for 16S and 16.9% for COI) was recorded between M. commensalis, the only Indo-West Pacific species with a one-valved petasma, and the other species with a two-valved petasma. Phylogenetic analyses using neighbor-joining, maximum parsimony, and maximum likelihood generated mostly identical tree topologies in which M. commensalis is distantly related to the other species. Two clades were resolved for the remaining species, one with and the other without a stridulating organ, supporting the main groupings of the recent taxonomic revision. Results of the present study also indicate that the deep-water forms represent a relatively recent radiation in Metapenaeopsis.

Studies on interaction of bovine serum albumin with indo-1 by fluorescence spectroscopic method

The binding-site number was calculated by using fluorescence spectroscopic method with bovine serum albumin(BSA) and Indo-1 as protein and ligand models, respectively. The method for calculating binding-site number in BSA for Indo-1 was developed based on the relationships between the changes of Indo-1 fluorescence intensity and the analytical concentration of BSA. And the interaction of BSA with Indo-1 was investigated comprehensively by using fluorescence techniques as well as fluorescence resonance energy transfer, and the thermodynamic parameters were calculated according to the changes of enthalpy on temperature.,

牛血清白蛋白与Indo-1相互作用的荧光光谱法研究

以牛血清白蛋白(Bovine serum album in,BSA)与荧光探针Indo-1为蛋白质和配体模型,基于Indo-1的荧光强度与BSA的分析浓度间的关系,建立了计算二者相互作用位点数的方法,并利用荧光共振能量转移及各种荧光技术对Indo-1和BSA的相互作用进行了研究.结果表明,Indo-1在BSA中有3个作用位点,这3个作用位点与BSA中的212位色氨酸(Trp 212)间的距离分别为2.93,2.57和2.40 nm;Indo-1通过疏水性作用进入到BSA的3个疏水性空腔.在荧光猝灭实验中,通过M icrolab 500系列进样器和PTI荧光仪的联用实现了荧光强度的自动和实时记录.

某些镧系化合物化学键特性的INDO研究

本文用INDO方法研究了不同价态镧系化合物的成键性质和4f轨道在成键中的作用,结果表明,镧系化合物的成键受许多因素,如价态、半径、配体、配位数、空间构型等影响。不同配体与镧系元素成键的强度差别较大;高价态的共价性大于低价态的;配位数低的大于配位数高的。某些特殊构型的镧系化合物除σ键外,还形成重叠较好的π配键,使Ln—L键共价性大大增强。4f轨道在成键中的作用比5d的少得多,三价(二价态)的4f轨道基本定域(<0.1％),四价态的4f轨道对成键的贡献明显增大,可接近1％。

Further Indo-West Pacific palaemonoid shrimps (Crustacea : Decapoda : Palaemonoidea), principally from the New Caledonian region

Based on the material deposited in the Museum national d'Histoire naturelle, Paris, collected from the Indo-West Pacific, principally from the New Caledonian region, the present paper reports 117 palaemonoid shrimp species, which belong, respectively, to Anchistioididae ( one genus, one species), Gnathophyllidae ( one genus, one species), Palaemonidae Palaemoninae ( seven genera, nine species), and Palaemonidae Pontoniinae ( 30 genera, 106 species), including eight new species. The new species are all Pontoniinae: Mesopontonia brevicarpalis sp. nov., Palaemonella komaii sp. nov., Periclimenes crosnieri sp. nov., Periclimenes forgesi sp. nov., Periclimenes loyautensis sp. nov., Periclimenes paralcocki sp. nov., Periclimenes paraleator sp. nov., and Periclimenes pseudalcocki sp. nov. The last six new species are members of the deep-water "Periclimenes alcocki species complex'', which has more than two ( usually four) pairs of dorsolateral telson spines anterior to the posterior telson margin, the cornea is usually reduced, the dactyl of the major second chela is generally flanged and the chela is sometimes covered with small tubercles. The complex is usually found at more than 200m depth in the West Pacific. The species can be distinguished from each other by the armature of ambulatory propod and dactyl, diameter of cornea, rostrum shape and the number of pairs of dorsolateral telson spines. Mesopontonia brevicarpalis sp. nov., from the southeast coast of Africa, is the seventh species of the genus. Palaemonella komaii sp. nov. is very similar to Palaemonella dolichodactylus Bruce, 1991 and Palaemonella hachijo Okuno, 1999. These three species share the features of very long and slender ambulatory pereiopods with the dactyl more than eight times longer than its basal depth and with several long setae on the dorsal dactylar margin.

Phylogeny and evolution of the Drosophila nasuta subgroup based on mitochondrial ND4 and ND4L gene sequences

The sequences of the mitochondrial ND4 gene (1339 bp) and the ND4L gene (290 bp) were determined for all the 14 extant taxa of the Drosophila nasuta subgroup The average A + T content of ND4 genes is 76.5% and that of ND4L genes is 83.5%. A total of 114 variable sites were scored. The ND4 gene sequence divergence ranged from 0 to 5.4% within the subgroup. The substitution rate of the ND4 gene is about 1.25% per million years. The base substitution of the genesis strongly transition biased. Neighbor-joining and parsimony were used to construct a phylogeny based on the resultant sequence data set. According to these trees, five, distinct mtDNA clades can be identified. D. niveifrons represents the most diverged lineage. D, sulfurigaster bilimbata and D. kepulauana form two independent lineages. The other two clades are the kohkoa complex and the albomicans complex. The Kohkoa complex consists of D. sulfurigaster sulfurigaster, D. pulaua, D. kohkoa, and Taxon-F. The albomicans complex can be divided into two groups: D. nasuta, D. sulfurigaster neonasuta, D. sulfurigaster albostrigata, and D.. albomicans from Chiangmai form one group; and D. pallidifrons, Taxon-I, Taxon-J, and D. albomicans from China form the other group. High genetic differentiation was found among D. albomicans populations. Based on our phylogenetic results, we hypothesize that D. niveifrons diverged first from the D, nasuta subgroup in Papua New Guinea about 3.5 Mya. The ancestral population spread to the north and when it reached Borneo, it diversified sequentially into the kohkoa complex, D. s. bilimbata, and D. kepulauana. About 1 Mya, another radiation occurred when the ancestral populations reached the Indo-China Peninsula, forming the albomicans complex. Discrepancy between morphological groupings and phylogenetic results suggests that the male morphological traits may not be orthologous. (C) 1999 Academic Press.

Development and characterization of polymorphic microsatellite loci in the endangered Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis)

The finless porpoise (Neophocaena phocaenoides) is one of the smallest cetacean species widely distributed in the shallow coastal waters of the Indo-Pacific Oceans. The population size of the Yangtze subspecies (N. p. asiaeorientalis) has sharply decreased in the last two decades and access to objective data on its population structure and genetic diversity would be of great assistance for their proper management. Here we report on the isolation of nine polymorphic microsatellite using the "Fast Isolation by AFLP of Sequences Containing repeats" (FIASCO) protocol. Polymorphism was assessed using 30 porpoise individuals randomly sampled in the Yangtze River. The number of alleles per locus varies from 2 to 9, with an average value of 5.56, whereas the ranges of observed and expected heterozygosi ties were 0.300-0.633 (mean 0.496) and 0.473-0.804 (mean 0.659), respectively.

稀土冠醚络合物的研究

稀土冠醚配合物由于其有趣的稀土／冠醚配比和结构以及其在稀土萃取分离、光谱探针等方面应用的可能性，引起了人们极大的研究兴趣，在固体配合物合成、晶体结构、配合物稳定性、冠醚在稀土萃取分离中应用等方面展开了广泛的研究。但是，对于不同配比配合物的反应机理及本质的探讨尚注意不够；三元配合物的合成工作较少；冠醚对稀土元素萃取需要有大体积对阴离子存在，且萃取效率不高，分离因数低。所有这些表明，对稀土冠醚配合物的合成及其性质，有必要作进一步深入的研究。本论文以冠醚(2,2)及其衍生物以及18－冠－6作为配体，研究其稀土配合物的结构及性质，取得了一些有意义的结果。1．合成轻稀土La-Nd硝酸盐与冠醚(2,2)配合物并测定了它们的晶体结构。晶体属于三斜晶系，空间群PT。随着原子序数增加，晶胞体积减小。配合物中，中心离子位于冠醚环中心，三个硝酸根均以双齿形式配位，其中两个位于位阻较小的冠醚环一侧，另一个位于其对侧。中心离子的配位数为12。指出硝酸稀土冠醚(2,2)配合物存在着两种不同的结构: [Ln(NO_3)_3(2,2)I (Ln = La - Sm); [Ln(NO_3)_2(2,2)]NO_3 (Ln = Eu)。用“堆积原理”解释了这种结构差异的原因。2．原INDO法计算了配合物La(NO_3)_3(2,2)的净电荷分布、电子结构、键级。用XPS验证了净电荷分布计算结果。键级计算结果表明，镧与配位原子间的键具有一定程度的共价性。镧的5d轨道对共价成份的贡献最大，而4f轨道基本上不参与成键，镧与冠醚环上氮原子间具有较强的作用，从而提高了稀土冠醚(2,2)配合物的稳定性。3．合成了稀土苦味酸盐与冠醚(2,2)配合物。元素分析结果指出：La、Pr-Sm配合物为无水的1:1配合物，Eu-Lu配合物为含水配合物。用IR、NMR、TG研究了La、Pr-Sm四个配合物的性质。IR研究结果表明，冠醚环上C-O-C、C-N-C反对称伸缩振动频率在形成配合物后向低波数位移40 cm~(-1)左右。N－H伸缩振动频率向低波数位移并发生分裂，其中一个分裂峰位移达-130 cm~(-1)。配位后，苦味酸C－O伸缩振动频率向低波数位移约10 cm~(-1)，苯环上硝基面外摇摆振动发生分裂，表明苦味酸以酚氧原子及硝基氧原子参与配位。~1H NMR结果表明，配位后，冠醚环上质子向高场位移。4．合成了未见文献报道的十五个稀土－PMBP－18C6三元配合物。元素分析结果指出配合物组成为1:3:1，用IR、NMR、FAB－MS TG－DTA研究了配合物性质。IR结果指出：形成配合物后，冠醚C－O－C反对称伸缩振动频率位移较小，表明了稀土与冠醚间的作用较弱。FAB－MS中[Ln(PMBP)_2·18C6]~+谱峰丰度小于[Ln(PMBP)_2]~+，也反映了三元配合物中稀土与冠醚间的较弱的作用，表明三元配合物的稳定性不如二元配合物。选择La~(3+)、Lu~(3+)、Y~(3+)、Pr~(3+)、Eu~(3+)、Ho~(3+)的三元配合物进行了~1H NMR研究。对抗磁性离子La~(3+)、Lu~(3+)、Y~(3+)的配合物，与自由配体比较，各组质子均向高场位移。顺磁性离子Pr~(3+)、Eu~(3+)配合物中，PMBP苯环质子发生更大位移，同时谱峰宽化。冠醚环上质子及PMBP甲基质子共振峰消失。Ho~(3+)配合物由于强烈的宽化作用而没有出现质子核磁共振信号。5．研究冠醚(2,2)的两种衍生物对Pr~(3+)的萃取行为，结果表明，在没有大体积对阴离子存在下，冠醚对Pr(NO_3)_3能有较高的萃取率，这种现象尚未见文献报导。考察了冠醚浓度、稀土浓度等对萃取分配比的影响，随着冠醚浓度增加，萃取分配比增加，而稀土浓度增加时，萃取分配比下降。

稀土——冠醚配合物的合成、结构、性质及应用研究

近20年来，冠醚类化合物的络合选择性以及稀土——冠醚络合物在结构和性质上的特殊性一直吸引着人们的研究兴趣，研究稀土冠醚的配位作用，探讨冠醚在稀土分离，作为光谱探等方面的应用一直为人们所重视，并取得了丰富的研究资料，但由于稀土冠醚配位作用的复杂性，目前人们尚无法解释许多实验事实，因此，有必要进行配合物的深入研究，同时考虑到目前高纯稀土生产中，对少量的矸金属、矸土金属杂质仍无十分有效的分离方法，而冠醚对矸金属、矸土金属的配位能力大于稀土，利用冠醚有可能实现这一分离，为此我们完成了如下工作：研究了水合稀土硝酸盐与B12C4、Cy12C4和B15C5络合物的合成结构和性质。对于B12C4，轻重稀土均可得到稳定的无水络合物（1：1），对Pr、Cd、Lu的络合物的晶体结构分析表明，三者具有相同的结构特征。Cy12C4表现出了与B12C4相似的配位性能，它与轻重稀土均可得到稳定的无水络合物；对La、Eu、Lu络合物的晶体结构研究表明，La、Eu络合物中三个NO_3~-呈不对称排列，这在“伞型”结构的稀土硝酸盐络合物中尚无报道；对于B15C5，轻重稀土表现出了不同的配位能力，其中，轻稀土络合能力较强，可以得到无水的直接配位络合物R(NO_3)_3、B15C5(R=La-Gd)，但Sm和Gd络合物的稳定性已变差，晶体结构及红外数据表明，这些络合物具有相同的结构特征；重稀土与B15C5得到含水配恰 物；通过对典型含水重稀土络合物Yb(NO_3)_3、3H_2O、B15C5和的结构和性质研究，指出B15C5不参与中心离子配位是含水重稀土-B15C5络合物的结构特点。研究了La(NO_3)_3、L(L=16C5, Me_216C5)及Lu(NO_3)_3、3H_2O、16C6的合成结构和性质，分析了它们的结构特点。初步总结了水合稀土盐与冠醚的配位特点，分析了1：2冠醚直接配位型络合物难以形成的原因及影响冠醚与水配竞争的因素，总结了稀土——冠醚络合物的结构特征。用INDO法研究了Lu(NO_3)_3、B12C4及Lu(NO_3)_3、Cy12C4电子结构，比较了取代基苯环和单环已基对配体配位性能的影响。研究了DCC对HNO_3溶液中Ca和La的萃取，指出DCC对硝酸镧基本不萃取，对Ca萃取率可达20%。因而具有明显的分离作用。

中性芳烃烯土氯化铝配合物的合成结构及催化反应性能

本文以经铝粉活化的AlCl_3与无水氯化稀土在芳烃溶剂中反应，分离到了一系列含有不同芳烃配体的中性芳烃稀土氯化铝配合物。对这些配合物进行了元素分析和水解色谱分析，证实了配合物的组成。这是迄今为止继Cotton 报道的S_m(C_6Me_6)(AlCl_4)_3之后仅有的溶液中合成的芳烃配合物的例子。对配合物进行了红外、校磁共振谱的测定，发现配合物中配合体的特征吸收和化学位移与游函的配体一致，说明配合物中配体与中心金属函子的作用较弱。对典型的配合物进行了X－射线晶体结构测定。对含相同中心函子不同配体的配合物结构研究发现，在配体与中心金属函子的作用中，电子效应和空间效应同时反方向起作用，即电子效应加强配体与中心金属函子的作用，空间效应阻碍配体与中心金属离子作用。这两种作大约在二甲基苯为配体时达到平衡。其后，随着电子性的甲基增多，两种效应对配体与中心金属离子作用的影响相互抵消。同时对含有相同配体不同中心金属离子的配合物的结构研究中发现，中心金属离子对配合物的结构没有明显的影响，其键参数的差别主要来自离子半径的变化。对配合物的电子结构进行了研究。对S_m(CH_3C_6H_6)(AlCl_4)_3的INDO计算表明：1．配体甲苯环上电子云密度有所下降，并且邻、对位下降幅度较间位大、六个环上C原子电子云分布与游离和甲苯比较差别缩小。2．环上H原子的电子云密度降低，说明配位对环上H原子有一定的活化作用。3．中心离子的正电荷下降。中心稀土离子主要以5d、6s、6p参与成键。用L_a(C_6H_6)(AlCl_4)_3和Nd(C_6H_6)(AlCl_4)_3作催化剂研究了苯与已烯－1的烷基化反应，发现配合物的催化活性比相应的氯化稀土大，这可能是由于配合物的生成使Zn~(3+)在芳烃菏剂中可以均相存在，因而提高了催化剂的活性。另外发现，反应在较低产率即达到平衡，这可能是存在着已烯－1与苯在催化剂上的络合一释络平衡。