THE EFFECTS OF LANTHANIDE IONS AND THEIR COMPLEXES ON THE PHASE-TRANSITION PROPERTY OF DIPALMITOYLPHOSPHATIDYLETHANOLAMINE LIPOSOMES

The effects of metal ions and lanthanide complexes on the gel-to-liquid crystal phase transition temperature T-m of dipalmitoylphosphatidylethanolamine liposomes have been studied by differential scanning calorimetry (DSC) method. The results show that the addition of metal ions to the dipalmitoylphosphatidylethanolamine (DPPE) liposomes dispersions increases the main phase transition temperature T-m in the order of monovalent< divalent< trivalent cations. The enhancement of T-m is not large as increasing the lanthanide ions concentration. The enhancement of Pr3+ is larger than that of La3+. Remarkable differences were observed between La-citrate and La-lactate complexes at different pH solutions. At pH 7.0, La-citrate complex has no effect on the T-m, La-lactate complex, however, increases the T-m value, and the increase is larger than that of free lanthanide ions at the same concentration. The decrease of pH of complexes solutions lowers the phase transition temperature. We have preliminarily discussed the mechanism of the enhancements of lanthanide ions and the synergism of lanthanide ion and lactate ligand follow the ion induced dehydration of lipid and the potential effects of ion-lipid interaction.

STUDY ON COMPLEXES OF RARE-EARTH WITH L-PHENYLALANINE BY POTENTIOMETRY WITH CALORIMETRY

The stability constants and thermodynamic functions for complexes of rare earth with L-phenylalanine have been determined by potentiometry and calorimetry at 25-degrees-C and ionic strength of 0.15mol.dm-3(NaCl). Stability of the complexes shows the "Tetrad effect". The entropy change makes a predominant contribution to the stability of these complexes. The ligand is coordinated to rare earth ions through its -CO2- and -NH2 group, and dehydration of ions plays an important role in coordination reaction.

THERMAL DECOMPOSITIONS OF SOME BIOINORGANIC COMPLEXES OF EUROPIUM

Thermogravimetric and derivative thermogravimetric investigations for three kinds of bioinorganic complexes of europium with N-acetyl-DL-alanine, N-acetyl-DL-valine and DL-alanyl-DL-alanine have been performed. It was found that the water molecules in these solid state complexes are not directly coordinated to the europium ion and that there may be three or four steps in the thermal decomposition process of these complexes after dehydration. The possible thermal decomposition reactions of these bioinorganic complexes have been suggested and discussed.

CRYSTAL STRUCTURE AND THERMAL ANALYSIS OF ERBIUM COMPLEX WITH BENZENE ACETIC ACID

The crystal structure of erbium (III) complex of benzene acetic acid is reported. The complex crystallizes in the monoclinic space group P2(1)/a with a = 0,9008(3)nm, b=1.4242(5) nm, c=1.8437(7) nm, beta=98.80(3)degrees, V = 2.337(1) nm(3), Z = 4. The mechanism of thermal decomposition of complex has been studied by TG-DTG-DTA. The activation energy for dehydration reaction has been calculated by Freeman Carroll method. The enthalpy change for dehydration and phase change process has been determined.

THERMAL ANALYSIS AND INFRARED SPECTRA OF DIALKYLAMMONIUM TETRAC HLOROCUPRATE

The thermal stability and the solid solid phase transitions in Ills compounds with n = 7-12 have been studied by DSC and TG methods. Comparision with CnZn compounds want made. The nature of three phases of CnCu has been discussed in terms of infrared spectroscopy and the assignment of the phase transitions has been given. The thermal stability of CnCu is lower than that of CnZn and presents an obvious odd even effect. All of these compounds exhibit two solid solid phase transitions in the temperature range of 248-337 K. The peak tempe nature of phase transitions changes regularly. The peak temperature or the main phase transition increases with the chain length. The total transition enthalpies and entropies increase with increasing chain length. When n <= 9, the high temperature phase exists in a partial disorder state. When n >= 10, the high temperature phase exists in a conformational disorder state. The main phase transition and the phase transition at 307.7 K of CnCu may mainly are from the change of the packing structure and the change of the partial conformational order-disorder of alkyl chain, respectively.

TWO SPECIFIC CAUSES OF CELL MORTALITY IN FREEZE-THAW CYCLE OF YOUNG THALLI OF PORPHYRA YEZOENSIS (BANGIALES, RHODOPHYTA)1

Porphyra yezoensis Ueda is an important marine aquaculture crop with single-layered gametophytic thalli. In this work, the influences of thallus dehydration level, cold-preservation (freezing) time, and thawing temperature on the photosynthetic recovery of young P. yezoensis thalli were investigated employing an imaging pulse-amplitude-modulation (PAM) fluorometer. The results showed that after 40 d of frozen storage when performing thallus thawing under 10 degrees C, the water content of the thalli showed obvious effects on the photosynthetic recovery of the frozen thalli. The thalli with absolute water content (AWC) of 10%-40% manifested obvious superiority compared to the thalli with other AWCs, while the thalli thawed at 20 degrees C showed very high survival rate (93.10%) and no obvious correlation between thallus AWCs and thallus viabilities. These results indicated that inappropriate thallus water content contributed to the cell damage during the freeze-thaw cycle and that proper thawing temperature is very crucial. Therefore, AWC between 10% and 40% is the suitable thallus water content range for frozen storage, and the thawing process should be as short as possible. However, it is also shown that for short-term cold storage the Porphyra thallus water content also showed no obvious effect on the photosynthetic recovery of the thalli, and the survival rate was extremely high (100%). These results indicated that freezing time is also a paramount contributor of the cell damage during the freeze-thaw cycle. Therefore, the frozen nets should be used as soon as time permits.

Cloning and characterization of beta-carotene ketolase gene promoter in Haematococcus pluvialis

The unicellular green alga Haematococcus pluvialis accumulates a highly valuable ketocarotenoid, astaxanthin, under various environmental stresses. beta-carotene ketolase (BKT) plays a key role in astaxanthin biosynthesis in H. pluvialis. In this paper, an approximate 700 bp 5'-flanking region of the bkt gene containing a putative promoter was cloned through walking upstream. The results of the sequence analysis showed that this bkt 5'-flanking region might have cis-acting elements such as sterol regulatory element (SRE-1)-like motifs, the C-repeat/dehydration responsive element (DRE) and al-3 proximal element (APE)-like motifs, except for typical TATA and CCAAT boxes. The results of the P-galactosidase assay and the transient expression of lacZ driven by a series of sequential deletions revealed that a minimal promoter-like region might exist from -630 to -408 bp, and the highest promoter activity was observed to span the positions from -630 to -308 bp. The results of the site-directed mutagenesis of a C-repeat/DRE and two APE-like motifs in a promoter-like region (-630 to -308 bp) suggested that two APE-like motifs might be essential for transcriptional control of the bkt gene.

Molecular cloning, characterization and evolutionary analysis of phytoene desaturase (PDS) gene from Haematococcus pluvialis

Phytoene desaturase is one of the most important enzymes necessary for the biosynthesis of carotenoids in some cyanobacteria, green algae and plants. In this study, genomic DNA and cDNA of pds were cloned from unicellular green alga Haematococcus pluvialis strain323 using PCR and RT-PCR methods. The cDNA was cloned into plasmid pET-28a and efficiently expressed in Escherichia coli BL21. The complete genomic PDS gene of H. pluvialis, 3.3 kb in size, included eight exons and seven introns. To locate transcriptional regulation elements, an approximate 1 kb of 5'-flanking region was isolated by genome-walking method. Results of bioinformatic analysis showed several putative cis-elements e.g. the ABRE motif (abscisic acid responsive element), the C-repeat/DRE (dehydration responsive element) motif and the GCN4 motif were located in 5'-flanking region of pds. Results of phylogenetic analyses reveal that different sources of PDS genes form a separate clade, respectively, with 100% bootstrap support. Moreover, a maximum likelihood approach was employed to detect evidence of positive selection in the evolution of PDS genes. Results of branch-site model analysis suggest that 7.9% of sites along the green algal branch are under positive selection, and the PDS gene in green algae exhibits a different evolutionary pattern from its counterparts in cyanobacteria and plants.

Evaluation of the pyrolytic and kinetic characteristics of Enteromorpha prolifera as a source of renewable bio-fuel from the Yellow Sea of China

The pyrolytic and kinetic characteristics of Enteromorpha prolifera from the Yellow Sea were evaluated at heating rates of 10, 20 and 50 degrees C min(-1), respectively. The results indicated that three stages appeared during pyrolysis; dehydration, primary devolatilization and residual decomposition. Differences in the heating rates resulted in considerable differences in the pyrolysis of E. prolifera. Specifically, the increase of heating rates resulted in shifting of the initial temperature, peak temperature and the maximum weight loss to a higher value. The average activation energy of E. prolifera was 228.1 kJ mol(-1), the pre-exponential factors ranged from 49.93 to 63.29 and the reaction orders ranged from 2.2 to 3.7. In addition, there were kinetic compensation effects between the pre-exponential factors and the activation energy. Finally, the minimum activation energy was obtained when a heating rate of 20 degrees C min(-1) was used. (C) 2009 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Trace element composition of peridotites from the southern Mariana forearc: Insights into the geochemical effects of serpentinization and/or seafloor weathering

Peridotites from the southern Mariana forearc were sampled on the landward trench slope of the Izu-Bonin-Mariana (IBM) subduction zone by dredging. These mantle wedge peridotites underwent hydration by fluid derived from a dehydrated descending slab, and later interacted with seawater after emplacement at or near the seafloor. This study investigates how these two different rock-fluid interaction processes influenced trace element distribution in the southern Mariana forearc peridotites. We measured trace element concentrations of peridotites from the southern Mariana forearc. The southern Mariana forearc peridotites are characterized by a distinct seawater-like REE pattern with an obvious negative Ce anomaly, and La shows good correlation with other REEs (except Ce). In addition, there is a great enrichment of U, Pb, Sr and Li elements, which show a distinct positive anomaly relative to adjacent elements in the multi-element diagram. For the seawater-like REE pattern, we infer that REEs are mainly influenced by seawater during peridotite-seawater interactions after their emplacement at or near the seafloor, by serpentinization or by marine weathering. Furthermore, the anomalous behavior of Ce, compared with other rare earth elements in these samples, may indicate that they have undergone reactions involving Ce (IV) when the peridotites interacted with seawater. Positive U, Pb, Sr and Li anomalies are inferred to be related to seawater and/or fluids released during dehydration of the subducting slab.

Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye

In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.

俯冲带深部流体特征——以西南天山变质俯冲杂岩为例

The subduction zone is an important site of the fluid activity and recycling of chemical elements. The fluid characteristic of deep subduction zones is a top scientific problem attracting the petrologists, geochemists and tectonists. In this dissertation, the characteristics of fluid activity within a deep subduction zone have been explored on the basis of the studies on the petrography, mineral chemistry, fluid inclusions, geochemistry and metamorphic P–T conditions of the omphacite-bearing high-pressure veins and related hosts from the low-temperature/high-pressure metamorphic belt in southwestern Tianshan, China. Multiple high-pressure veins are exposed in host eclogites and blueschists. The veins are composed predominantly of omphacite, garnet, quartz, and other minerals. Some veins contain cm-sized rutiles. In general, the vein can be divided into three types, the ‘in situ dehydration’ vein, the ‘external transport’ vein and the ‘composite’ vein. The omphacites within the veins and related host rocks contain lots of two-phase or three-phase primary fluid inclusions. The final melting temperature (Tfm) of fluid inclusions varies mainly from -0.6 to -4.3 °C, the homogeneous temperature (Th) varies from 185 to 251 °C, the salinity varies from 1.1 to 6.9 wt.% NaCl equivalent and the density varies from 0.81 to 0.9 g/cm3. The fluids were released under the conditions of T = 520–580°C and P = 15–19 kbar at blueschist facies to eclogite facies transition. The fluids include not only Li, Be, LILE, La, Pb-enriched and HFSE- and HREE-depleted aqueous fluids but also HFSE (Ti-Nb-Ta)-rich aqueous fluids. The complex composed of aluminosilicate polymers and F was the catalyst which had caused the Ti-Nb-Ta to be dissolved into the fluids. During the transport of the LILE-rich and HFSE- and HREE-poor fluids, they can exchange some chemical elements with country rocks and leach some trace elements in some extent. The rutile could be precipitated from the HFSE (Ti-Nb-Ta)-rich aqueous fluids when CO2 was added into the fluids. The host rocks could obtain some elements, such as Ca, Cs, Rb, Ba and Th, from the external fluids. The fluids with complex composition had been released within the deep subduction zone (>50 km) in Early Carboniferous during the subduction of the South Tianshan Ocean under the Yili–Central Tianshan Plate. The results obtained in this dissertation have made new progress compared with the published data (e.g. Tatsumi, 1989; Becker et al., 1999; Scambelluri and Philippot, 2001; Manning, 2004; Hermann et al., 2006; Spandler and Hermann, 2006).

华北克拉通孔玆岩系中石榴子石花岗岩的成因：熔体与残留相混合机制的研究

The most widespread rock associations in the Western Block of North China Craton are khondalites distributed mainly in Jining, Liangcheng and Datong. A large quantitiy of garnet-bearing granites are contained in the khondalites. A great deal of research has been carried out on them by previous researchers. Studies of these garnet-bearing granites consist essentially of structural characteristics, petrography and geochemistry, and finally geochronological determinations. Summing up these researches, it will not be difficult to see that all of these authors have regarded these large numbers of garnets (up to 20%) contained in granites as crystallized products from magmas, but they have not proved this from petrological perspective. Theoretically, there are possibly three kinds of petrogenesis as to these garnets. The first one is that they have been transferred to the granites from khondalites by melt when anatexis happened to khondalites, and they, in essence, are residual metamorphic garnets; The second one is that when the khondalites were being melted, these garnets were produced from biotite dehydration melting, and the newly formed garnets intruded together with the melt and eventually molded the garnet-bearing granites. Garnets of this possible kind either showed independent crystals, or garnets from khondalites took place secondary growth under favorable temperature and pressure conditions for their crystallization; The last possibility is that these garnets were crystallized from magmas in which suitable pressure, temperature and composition were available. These garnets, generally, should be fine-grained. The aim of this study is, through examining the mineral chemistry of the garnets and the whole rock chemistry, to ascertain under which kind of mechanism, in the world, did these garnets form? Besides, we try to calculate the temperatures under which khondalites began melting and reactions of the garnets and the cooled melts happened by garnet-biotite thermometry. The whole rock chemistry analyses of the garnet-bearing granites tell us that all the samples are strongly peraluminous (A/CNK greater than 1.1) on the A/NK vs. A/CNK plot. On the SiO2-K2O plot, the granites are mainly constrained to be high-K calc-alkaline and calc-alkaline series, consistent with previous researches. On the ACF（（Al2O3-Na2O-K2O）-FeO(T)-CaO） discrimination plot, all the six garnet-bearing granite samples drop into the area of S-type granites. The relationship between CaO/Na2O and SiO2 shows that the overwhelming majority of garnet-bearing granites have a CaO/Na2O value over 0.3, revealing that they probably come from metagreywacke precursors or mediate-felsic orthogeneisses compositionally similar to them. Detailed EPMA analyses conducted on the garnets contained in the garnet-bearing granites show that all the garnets are dominated by almandine and pyrope, which occupy 92-96% (Weight Percentage) of each garnet analyzed, typical of granulite facies. Their chemical composition is entirely different from those crystallized in magmas, but extremely similar to those of typical granulite facies metapelites in khondalites and typical granulites, indicating all the garnets to be metamorphogenic. In addition, REEs distribution patterns of the garnets are totally different from typical biotite granites and peraluminous granites. In other words, both LREE and HREE of our garnets are evidently lower than those from these two kinds of rocks. Moreover, compared to the REE pattern of the garnets from typical amphibolites, LREE content of our garnets is obviously higher and HREE content is a little lower. However, REE patterns of our garnets are completely in harmony with those of garnets from typical granulites. So, the REE patterns of garnets, again, prove that all the garnets we studied are metamorphogenic. Biotites appear in two forms, being as inclusions in the garnet and as selvages immediately adjacent to the garnet, respectively. Two reactions and their corresponding temperatures, with the help of petrography and Garnet-Biotite geothermometers, could be obtained, which are Bt+ Pl+ Qtz→Kfs+ Opx+ Grt+ melt as positive reaction and Kfs+ Grt+ melt→Bt+ Pl+ Qtz as reverse reaction, respectively. Summing up the discussion above, we declare that the garnet-bearing granites distributed in the Western Block of North China Craton are the mixture of melts and restites resulted from biotite dehydration melting. The garnets contained in the restites are the products from biotite dehydration melting and restites from the khondalites, respectively.

中国华北和美国加州地区地震层析成像研究

In recent years seismic tomography has become a powerful tool for studying the three-dimensional crust and mantle structure. In this study, we collected a large number of regional and teleseismic travel-time data and used seismic tomography method to study the relationship between earthquake occurrence and crustal heterogeneity for the 1992 Landers earthquake, heterogeneity and evolution of lithosphere under North China Craton and Southern California, and deep structure and origin of the Changbai intraplate volcano in Northeast China. Our results show a correlation between the seismic rupture zone and crustal heterogeneity. The distribution of the Landers aftershocks is cluster-like and separated or terminated in areas where low-velocity anomalies exist．Most of the large earthquakes with magnitudes >4.0 occurred in or around areas with high P-wave velocity．The possibility is that high-velocity areas are brittle and strong parts which can sustain seismogenic stress，and so can generate earthquakes. Our tomographic images show a very heterogeneous structure in the crust and upper mantle beneath Southern California. Three major anomalies in the upper mantle are revealed clearly beneath the southern Sierra Nevada, Transverse Ranges and Salton Trough. We consider that the high-velocity anomaly beneath the Transverse Ranges was formed through asymmetrical two-side convergence of subcrustal lithosphere and sinking to asthenosphere. Formation of the dense crust root and “drip structure” caused the high-velocity anomaly under the southern Sierra Nevada. The Salton Trough low is the response to the lithospheric extension when the Pacific plate was rifted away from the North American Plate. The tomograpic images beneath the North China Craton show that there exist different lithospheric structures under the different blocks. Complex, prominent low-velocity and high-velocity anomalies are imaged beneath the North China Basin, Trans-North China Orogen (TNCO), and Ordos Block which correspond to rifted, orogenic and cratonic lithospheres, respectively. The thickness of the three-type lithospheres is about 70, 90 and >250 km, respectively. Our results suggest that lithospheric thinning under the eastern part of North China Craton is due to long-term replacement and chemical and thermal erosion of the ancient lithosphere by the hot asthenosphere. The remains of ancient lithosphere exist either in the present upper mantle or have sunk into the mantle transition zone. Our tomographic result of the Changbai volcanic area suggests that the origin of the Changbai volcano is related to the deep dehydration of the subducted Pacific slab and corner flow in the big mantle wedge (BMW) above the stagnant Pacific slab.

扬子板块西部大陆地幔地球化学特征及壳幔演化－有关基性岩超基性岩的地球化学研究

The continental mantle geochemical characteristics and crust-mantle evolution in the west of Yangtze Plate was discussed through the study of some within-plate basic-ultrabasic rocks from Lower Proterozoic to Later Paleozoic in this paper. In the Lower Proterozoic, the plate subduction between the pre-Tethys Proterozoic Ocean Plate and paleo-Yangtze Plate induced some basic volcanic formed in the island arc-back arc surrounding, which were represented by Ailaoshan Group-Dibadu Formation-Dahongshan Group, and there existed EM I component in the mantle source. The Middle Proterozoic Caiziyuan peridotite was formed in the epicontinental basin at the ocean-land boundary or within-continent rift basin. Its mantle source could be metasomatized by the dehydration fluid of subducted plate, and much initial radioactive ~(143)Nd was added to the source. In the Later Proterozoic, some rifts at the epicontinent or within-continent was formed due to the pre-Tethys oceanic plate subduction, and within-plate hot-spot Dahongshan diabase came into being. The whole-rock isochronal age of diabase is 1066±110Ma, and its mantle source was enriched Nd isotope and trace element which was related to the primary volatile component from asthenosphere and mantle plume. Its mantle source was included "FOZO" component representing mantle plume. The layer ultramafic rocks located at the Panxi Rift in the Middle-Later Paleozoic were resulted from different period and source. The early ultramafic indicated the incipient action of Panxi Rift, which is residue of continental lithospheric partial melting. Its mantle source involved subducted material and had distinct EM II component. The Emeishan basalt in the Later Paleozoic was typical continental flood basalt and its source also contained EM II component. The subduction of paleo-Tethys Ocean Plate provided essential dynamic condition for the large-scale opening of Panxi Rift, while the mantle plume supplied much material for Emeishan basalt. However, the plume was contaminated by the metasomatized continental mantle lithosphere in its upwelling process, which resulted in the Sr isotopic and incompatible elemental enrichment, and the Nd isotope kept down the weak-depleted character of mantle plume. The magmatic history in the west of Yangtze Plate is the tectonic process between pre-Tethys, paleo-Tethys Oceanic Plate and Yangtze Plate in a long history. Due to the subduction of oceanic plate, the crustal source material took part in the crust-mantle evolution widely. the continental mantle lithosphere in the west of Yangtze Plate was metasomatized by the fluid released by the subducted plate and the primary volatile from deeper mantle, and the mantle source include obvious enriched component.