Caledonian reworking of Paleoproterozoic basement in the Cathaysia Block: Constraints from zircon U-Pb dating,Hf isotopes and trace elements

A combined study of zircon U-Pb dating, Hf isotopes and trace elements has been carried out for granodioritic neosomes of migmatites from the Tianjingping area in northwestern Fujian Province. Zircons are characterized by zoning, higher Th/U ratios （mostly≥0.1）, HREE enrichment, and positive Ce and negative Eu anomalies, and show features similar to magmatic or anatectic zircons. Apparent ^206Pb/^238U ages for the zircons are 447±2 Ma （95 % conf., MSWD=0.88）, corresponding to a Caledonian event. εHf（t） values are -13.3 to -9.7, indicating a crustal source. Two-stage Hf model ages are 1.7 to 1.9 Ga, suggesting that protolith of the migmates was probably formed in the Paleoproterozoic. The granodioritic neosomes have the characteristics of peraluminous calc-alkaline granite, and their REE patterns and trace elements spidergrams show features of middle to upper crustal rocks. Together with previous studies, we conclude that the protolith of the Cathaysia basement in the Tianjingping area was likely formed in the middle-late Paleoproterozoic and experienced partial melting during the Caledonian period. The recognition of Caledonian reworking of the Paleoproterozoic basement in the Cathaysia Block provides a new insight into the tectonic evolution of the Cathaysia Block in the Caledonian period and the interaction between the Cathaysia Block and the Yangtze Block.     

Responses of rice growth to copper stress under free-air CO2 enrichment （FACE）

The responses of rice to the second degree contamination of copper were studied by pot experiments under free-air CO2 enrichment （FACE） with 570 μmol ·mol^-1 of CO2. The results showed that the content of copper in rice leaves was reduced with the CO2 concentration reaching 570 μmol· mol^-1 and this happened more significantly under the second degree contamination of copper. Under FACE, activities of superoxide dismutase （SOD） enzyme in rice leaves treated by copper contamination were induced, whereas the contents of glutathione （GSH） and glutathione disulfide （GSSG） had no significant difference from the control. In the presence of ambient CO2, activities of SOD enzyme treated by copper pollution were suppressed during the whole rice growth, however, the contents of GSH and GSSG were induced at tillering and jointing stages, and then restored to the control levels in later growth under the second degree contamination of copper. With the rice growing, the content of malondialdehyde （MDA） rises continuously, but there had been no significant difference between the treatments at the same growth stage. Further studies are needed on the response mechanism of rice to Cu stress under elevated CO2.     

Paleoproterozoic reworking of ancient crust in the Cathaysia Block, South China: Evidence from zircon trace elements, U-Pb and Lu-Hf isotopes

A combined study of zircon LA-ICP-MS U-Pb dating, trace elements and Hf isotope was carried out for gneissic granite from the Sanzhishu area in Jingning, SW Zhejiang Province. Nearly all the zircons separated from the granite exhibited oscillatory zoning and high Th/U ratios (>0.1). The REE profile showed a pronounced positive Ce anomaly, negative Eu anomaly and an enrichment of HREE, which are typical characteristics of magmatic zircon. Thirteen concordant or nearly concordant analytical data yielded a weighted mean ²⁰⁷Pb/²⁰⁶Pb age of 1860±13 Ma (MSWD=0.084), representing the formation age of the granite. The magmatic zircons had negative εHf(t) values of −15.6 to −10.0 and two-stage Hf model ages of 3.1 to 3.4 Ga, indicating that the granites were formed by reworking of ancient crust. The major- and trace-element data indicate that the gneissic granites are metaluminous high-K calc-alkaline rocks and exhibit the same geochemical characteristics as aluminous A-type granites, implying the emplacement of the granite in a post-orogenic extensional tectonic setting. We conclude that the Paleoproterozoic crustal reworking event in the Cathaysia Block of South China marked the transition from assembly to break-up of the Columbia supercontinent. Supported by National Natural Science Foundation of China (Grant No. 40873004), Special Funds for National Scientific Research of Commonweal Industries, the Ministry of Land and Resources of China (Grant No. 2008110015), Opening Foundation of State Key Laboratory of Continental Dynamics, Northwest University (Grant No. 06LCD12) and the Project of Land and Resources Bureau of Zhejiang Province (Grant No. 2004005)     

Porphyry Cu-Mo deposits in the eastern Xing’an-Mongolian Orogenic Belt: Mineralization ages and their geodynamic implications

The eastern Xing’an-Mongolian (Xing-Meng) Orogenic Belt (XMOB) is one of the important areas of porphyry copper (Cu)-molybdenum (Mo) deposits in China. However, studies on the exact ages of mineralization and their geodynamic significance are very limited. In this study, granodioritic rocks from the Duobaoshan Cu deposit and Daheishan Mo deposit were selected to make zircon SHRIMP U-Pb analyses in order to constrain their mineralization ages. Geochronological data indicate that two episodes of mineralization took place in the Duobaoshan Cu deposits. The granodiorite related to the Duobaoshan porphyry Cu deposit was formed in the Early Paleozoic with zircon U-Pb age of 485±8 Ma, whereas the granodiorites related to the Sankuanggou skarn-type Cu deposit were emplaced in the Jurassic with zircon U-Pb ages of 176±3 and 177±3 Ma. In the Daheishan area of Jilin Province, the emplacement age of the granodiorite porphyry related to the porphyry Mo deposit was dated at 170±3 Ma, and the unmineralized monzogranite at 178±3 Ma. Therefore, two episodes of Cu-Mo mineralization were developed in the eastern XMOB, at ~485 Ma and ~175 Ma, respectively. Based on the geological history and spatial-temporal distribution of the granitoids in northeastern (NE) China, it is proposed that the Duobaoshan Cu deposit was related to the collision of the Xing’an and Erguna blocks in the Early Paleozoic, and the Sankuanggou Cu and Daheishan Mo deposits were related to subduction of the Paleo-Pacific plate during the Jurassic.     

Synthesis of novel polymer-bonded water-soluble metal porphyrins

The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru₃(CO)₁₂], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a−2d respectively. Treatment of 2a−2d with Merrifield’s peptide resin obtained 3a−3d. The compounds 3a−3d reacted with methyl iodide respectively gave 4a−4d. New complexes 4a−4d have been identified by IR, UV-visible spectra, and AES. Foundation item: Supported by the Natural Science Foundation of Hubei Province Biography: LI Zao-ying (1949-), female, Associate professor.     

Visible light-induced degradation of organic pollutants using Fe（ll） supported on silica gel as an effective catalyst

Silica gel-supported Fe（ll） （SiOFe） was prepared and used for heterogeneous degradation of sulforhodamine B （SRB） and 2,4-dichlorophenol （DCP） under visible irradiation （λ 〉 420 nm） as an effective catalyst. UV-visible spectra, and infrared Spectrophotometry （IR）, fluorescence, total organic carbon （TOC） and electron spin resonance （ESR） measurements were employed to analyze the photoreaction products. The results showed that SRB could be efficiently degraded by SiOFe/H2O2 system under visible irradiation with 100% decolorization and 72.3% TOC removal after 180 min illumination. The results of ESR and fluorescence measurements indicated that the oxidative process was predominated mainly by the hydroxyl radical （.OH） generated in the system.     

Low temperature thermodynamic study of the stable and metastable phases of vanadium

The low temperature thermodynamics of the stable phase of vanadium has been assessed by the polynomial and Debye models from the experimental data available in literature. By means of the con-strained nonlinear least squares curve fitting arithmetic,two sets of parameter values have been de-termined. Expressions of the thermodynamic functions Cp(T) and G(T)-H(298.15 K) at 0―298.15 K are presented. The low temperature thermodynamics of the metastable phase of vanadium can only be extrapolated by the Debye model. The expression of the thermodynamic function Cp(T) at 0―298.15 K is presented.     

Study on elastic modulus of individual ferritin

The mechanical property of individual ferritin was measured with force-volume mapping (FV) under contact mode of atomic force microscopy (AFM) in this work. The elastic modulus of individual ferritin was estimated by the Hertz mode. The estimated value of the elastic modulus of individual ferritin was about 250－800 MPa under a small deformation. In addition, the elastic modulus of individual ferritin was compared with that of the colloid gold nanoparticle.     

Quantum chemical and topological study on the insertion reaction of dichlorcarbene with acetaldehyde

The insertion reaction mechanisms of siglet and striglet CCI2 with CH3CHO have been studied by using the DFT, NBO, CCSD（T） and AIM method. The geometries of reactions, transition state and products were completely optimized by B3LYP/6-31G（d）. All the energy of the species was obtained at the CCSD（T）/6-31G（d,p） level. The calculated results indicated that all the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCl2 can not only insert the Cα--H （reaction I） but also can react with Cβ--H （reaction ll）. There are three main existing pathways and the products are P1 （CH3COHCCl2）, P2 （CH2COHCHCl2） and P4[CHCl2CHCHOH] respectively. Reaction II happens more easily according to the energy changes and the barrier in rate-controlling step. In addition, the important geometries in domain pathways have been studied by AIM theory. And also, the energy changes of H in the inserted C--H bond have been investigated.     

New material of microfossils from the Ediacaran Doushantuo Formation in the Zhangcunping area, Yichang, Hubei Province and its zircon SHRIMP U-Pb age

The Zhangcunping area is located at the north limb of the Huangling anticline in Yichang, Hubei Province. Here, the sedimentary succession of the Ediacaran Doushantuo Formation is similar with that in the Weng’an area, Guizhou Province. A large number of new microfossils (mainly acanthoacritarchs) from the Doushantuo Formation in this area are reported in this paper. The fossil assemblage shows similarity as the phosphatized biota of the Doushantuo Formation at Weng’an, Guizhou Province and the silicified biota of the Doushantuo Formation at the Yangtze Gorges, which suggests that the Zhangcunping area is a key for correlation of the Doushantuo Formation between the Weng’an area, Guizhou Province and the Yangtze Gorges. Besides, a new zircon SHRIMP U-Pb age (614.0±7.6 Ma) is first obtained from a horizon underneath the exposed surface in the middle of the Doushantuo Formation in the Zhangcunping area. This age not only provides a new datum for subdivision of the Ediacaran Doushantuo Formation, but also indicates that the age of the exposed surface in the middle of the Doushantuo Formation in the Yangtze Platform should be posterior to 614.0±7.6 Ma. Due to the horizon of the Weng’an biota situated above the exposed surface, the age of the Weng’an biota should be posterior to 614.0±7.6 Ma as well. Supported jointly by the Basic Foundation of scientific research work from Ministry of Science and Technology of the People’s Republic of China (Grant No. J0716), Science and Technology of China for fundamental work (Grant No. 2006FY120300-2), National Natural Science Foundation of China (Grant Nos. 40772013 and 40672022) and China Geological Survey (1212010611801-3)     

Simultaneous determination of trace rare earth elements and other elements in high purity terbium oxide (Tb4O7) by ICP-AES after HPLC separation using P507 resin

This article describes a new method for the simultaneous determination of trace rare earth elements (REEs) and non rare earth elements (NREEs) in high purity terbium oxide by ICP-AES after HPLC separation using P507 resin. The chromatographic separation of the analytes from the matrix using dilute nitric acid as mobile phase was studied. The experimental results showed that a favorable separation of trace metals (Cu and Gd) from the matrix (Tb) can easily be achieved by elution with dilute nitric acid within 25 min. The proposed method was applied to the determination of trace metals (Ca, Cu, Mg, Mn, Ni, Si, La, Ce, Pr, Nd, Sm, Eu and Gd) in high purity terbium oxide. The detection limits (DLs) for the analytes ranged from 0.4–4.0 μg· g⁻¹, and the recoveries are from 78%–105%. Foundation item: Supported by the National Science Foundation of China (No. 20007010108) and Wuhan Municipal Science & Technology Commission (No. 995004080) Biography, Wanjau Ruth (1961-), female, Ph. D. candidate, Kenyatta University, Kenya, research direction: determination of trace elements.     

Study on the specific interaction between angiogenin and aptamer by atomic force microscopy （AFM）

The specific interaction between angiogenin and aptamer has been investigated by using AFM. The specificity of the interaction is revealed by comparing the binding probability of aptamer to other elements in a series of control experiments. The results have shown that there is specific interaction force between angiogenin and aptamer. Moreover, the single molecular pull-off force between angiogenin and aptamer has also been determined using the Poisson statistical method to be 133.7±11.7 pN. These findings obtained are helpful to the better revelation of recognition mechanism between angiogenin and aptamer, which provided basis for further understanding the inhibition of the aptamer to angiogenic activity.     

Tunable multiple-channel filters based on photonic heterostructures using single-negative materials

We studied the multiple-channel filters based on photonic heterostructures consisting of single-negative permittivity and single-negative permeability media. The results showed that the number of resonance modes inside the zero-φeff gap increases as the number of heterogenous interface M increases. The number of resonance modes inside the zero-φeff, gap is equal to that of heterogenous interface M, and it can be used as M channels filter. This result provides a feasible method to adjust the channel number of multiple-channel filters. When losses are involved, the results showed that the electric fields of the resonance modes decay largely with the increase of the number of heterogenous interface and damping factors. Besides, the relationship between the quality factor of multiple-channel filters and the number of heterogenous interface M is linear, and the quality factor of multiple-channel filters decreases with the increase of the damping factor. These results provide feasible methods to adjust the quality factor of multiple-channel filters.     

Dead lithium phase investigation of Sn-Zn alloy as anode materials for lithium ion battery

In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through investigation, we found that the phases Li_xSn₄Zn₄(x = 2, 4, 6, 8) contributed to reversible capacity, while the phases Li_xSn₄Zn_8−(x−4)(x = 4.74, 7.72) led to capacity loss due to high formation energy, namely, they were the dead lithium phases during the charge/discharge process. And we come up with a new idea that stable lithium alloy phase with high lithiation formation energy (dead lithium phase) can also result in high loss of active lithium ion, besides the traditional expression that the formation of solid electrolyte interface film leads to high capacity loss. Supported by the National Natural Science Foundation of China (Grant No. 50771046), Natural Science Foundation of Guangdong Province (Grant No. 05200534), Key Projects of Guangdong Province and Guangzhou City (Grant Nos. 2006A10704003 and 2006Z3-D2031) and China Postdoctoral Science Foundation (Project No. 20080440764)     

Effects of the dispersed droplet sizes on the critical behavior of pseudobinary microemulsion

The critical behavior of pseudobinary microemulsion systems{water/sodium di(2-ethylhexyl)sulfo- succinate(AOT)/n-decane}with various droplet sizes was studied by measurements of refractive index. It was found that the critical exponentsβfor all systems approach 0.327 in a region sufficiently close to the critical temperature,which is consistent with 3D-Ising universality class.The critical temperatures linearly decrease as the dispersed droplet sizes increase.The critical amplitude almost linearly in- creases with increasing the dispersed droplet sizes.     

Investigation of biomembrane-drug interactions of different biomembranes by capillary electrophoresis

Biomembrane-coated capillaries are prepared by coating different kinds of biomembranes including mice red cell membrane, human red cell membrane and S-180 cell membrane on the inner surface of the capillary, respectively. Effects of immobilized biomembrane amount, pH and biomembrane species on the interactions between drugs and biomembranes have been evaluated. The results showed that the chromatographic retention factor for each drug was essentially related to the amount of immobilized biomembrane, the pH and the type of biomembrane.     

Cellulose beads modified by histidine: Preparation and adsorption behavior

Porous cellulose beads modified by histidine (PCBH) were prepared. The adsorption capacity of PCBH for divalent Mg(II), Cu(II), Pb(II) and Hg(II) ions were determined. The effects of the temperature, the initial pH value, the concentration of metal ion and PCBH ligand on the adsorption of Cu(II) Hg (II) were discussed. The adsorption process fitted to Freundlich adsorption isotherms for both metal ions. Adsorption rate constants were also found. Foundation item: Supported by the National Science Foundation of Hubei Province(98J033) Biography: HE Yong-bing (1945-), male, Associate professor.     

Holocene climatic and environmental changes recorded in Baahar Nuur Lake core in the Ordos Plateau, Inner Mongolia of China

A 5.3 m lake core was drilled in Baahar Nuur Lake in the Ordos Plateau, and measurements of meangrain size, organic δ 13C (δ 13Corg), organic carbon content (TOC), C/N, carbonate content, carbonate δ 13C(δ 13Ccar) and δ 18O (δ 18Ocar) were conducted for retrieving the Holocene chronosequence of climaticchanges based on 15 AMS 14C dates. The record documented four major stages of climate change inthe Ordos Plateau: (IV) a cold and dry condition before ～7.65 14C ka BP; (III) a warm and humid stagebetween ～7.65 and ～5.40 ka BP; (II) a generally drier and cooler climate since ～5.40 ka BP with twohumid events occurring from ～4.70 to ～4.60 ka BP and from ～4.20 to ～3.70 ka BP, and (I) a dry climatecharacterized by complete desiccation of the lake after 3.70 ka BP. Stage III can be further divided intothree sub-stages: (IIIa) a warm and humid episode from ～7.65 to ～6.70 ka BP, (IIIb) a warm and relativelydry episode from ～6.70 to ～6.20 ka BP, and (IIIc) the magthermal and maghumid episode of the Holo-cene from ～6.20 to ～5.40 ka BP.     

Influence of location-dependent protuberance damage on cell viability

The influence of femtosecond laser-induced damages on viability of olfactory ensheathing cells (OECs) is investigated. Several cytokinetic processes including cellular damage, recovery and death are discussed. Using femtosecond laser with the power of 100 μW and cutting speed of 2 μm/s, we cut the cellular protuberance with smaller diameter twice in different locations, and then observe the viability of the damaged cells. Under the same conditions, the root of protuberance with larger diameter is cut six times to observe changes of cellular shape. Whether the damage is located in the end, middle or root of protuberance with smaller diameter, the cell viability can recover within 3 h. When the damage is located in the root of protuberance with larger diameter, the damaged cell will die in the way of oncosis. Cytokinetic phenomena including intracellular high Ca²⁺ concentration, cellular morphologic change, recovery and oncosis are discussed. Meanwhile, high Ca²⁺ concentration is observed after femtosecond laser surgery. Therefore, femtosecond laser surgery is an important tool for establishing cell damage model and studying cytokinetics. Supported by National High Technology Research & Development Program of China (Grant No. 2006AA04Z307), Author of National Excellent Doctoral Dissertation of PR China (Grant No. 2006039), National Natural Science Foundation of China (Grant No. 50775104), Natural Science Foundation of Jiangsu Province (Grant No. BK2006507) and Jiangsu Provincial Research Innovation Program for College Graduates (Grant No. CX07B_086z)     

Estimating divergence times among subfamilies in Nymphalidae

The mitochondrial cytochrome oxidase subunit Ⅰ （COⅠ） gene and the nuclear elongation factor 1α （EF-1α） gene were sequenced from 13 species of Nymphalidae. Phylogenetic trees of Nymphalidae, which is the largest family in butterflies, were constructed based on the sequences determined from 13 species sequenced in our laboratory and an additional 43 species obtained from GenBank using the maximum likelihood （ML） and Bayesian methods. Relative-rate tests between lineages in these phylogenetic trees were performed. On the basis of the results of the relative-rate tests and fossil information of Satyrinae, Nymphalinae and Biblidinae, the average divergence times among the subfamilies are estimated as 44.2-87.1 million years ago （Ma）. These results will be helpful for better understanding of the origin and evolution of this family, as well as the divergence time of butterflies and other complex taxa.