新疆原油的特殊性及其在勘探、开发、炼制中的意义

国外石油中化学元素浓度大于它在岩石圈中平均含量的只有钒Ｖ。而新疆原油中有３３种元素，其含量超过中国岩石圈陆壳平均含量１～３个数量级，是新疆原油密度偏高的原因之一。新疆原油中富含的铼、金、银、镉、铟等元素是地壳稀缺而地幔富集的，说明新疆原油可能有来自地幔的成分；而其含有１８种生物中未发现的元素说明新疆原油可能有非生物成因成分；阿瓦提的油苗与有机成因原油正烷烃结构特征不同，不显奇偶优势的特征正是来自地幔的非生物成因油的特征。新疆原油中含有２３个亲石元素造成储油层亲油憎水特征。新疆原油的特殊性告诉我们：非生物成因烃的可能存在，为新疆的油气勘探提供了新的领域；含亲石元素多的原油，应研究降低密度、降低粘度与增加原油活性的开发技术，如注天然气或ＣＯ２气，以提高最终采收率，并对天然气和ＣＯ２气的勘探提出了需求；新疆原油中含有相对丰富的金、银、镍、钒等多种稀有贵重金属与有色金属的特征，是未来发展石油冶金工业的物质基础。

Analysis of Genetic Diversity of Dendrobium by RSAP Marker

[Objective] This study aimed to analyse the genetic diversity of and genet- ic relationship between 33 Dendrobium species by using RSAP （Restriction Site Amplification Polymorphism） marker technique. [Method] A PCR-reaction system was established, by which 33 pairs of primers screened from 45 pairs were used to con- duct the PCR amplification. [Results] The 33 pairs of primers produced 2 047 ampli- fied fragments, of which 2 044 were polymorphic, with a polymorphism rate of 99.8%, and each pair of primers produced 61.9 polymorphic fragments on average. The genetic similarity coefficients between species ranged from 0.081 to 0.442, sug- gesting that the experimental materials used in this study possess a wide genetic background. According to the result of RSAP, the 33 Dendrobium species were di- vided into 6 groups by the cluster analysis （UPGMA）. The result showed that the genetic relationship between D. acinaciforme and D. guangxiense was the closest, and that between D. sinense and either D. lituiflorum or D. hancockii was the fur- thest. [Conclusion] The result suggested that Dendrobium germplasms have a great genetic diversity. This study provides a molecular basis for the classification and breeding of Dendrobium plants, as well as the selection of hybridization parents in the future.

In situ self-nucleophilic synthesis of nano-Li_(4)Ti_(5)O_(12)/reduced graphite oxide composite with mesopore-oriented porous structure for high-rate lithium ion batteries

It is the core to improve the electron/ion transfer features of Li_(4)Ti_(5)O_(12) for achieving high-rate anode in lithium ion batteries.By directly using graphite oxide powder,nano-Li_(4)Ti_(5)O_(12)/reduced graphite oxide composite with mesopore-oriented porosity is prepared through one-pot facile ball-milling method in this work.Synthesis mechanism underlying the self-nucleophilic effect of oxygen-containing functional groups in graphite oxide is substantiated.Reactants can intercalate into graphite oxide bulk and in-situ generate nanoparticles.Subsequently,graphite oxide with nanoparticles generated inside can obtain a mesopore-oriented porous structure under ball-milling.Furthermore,the synergistic effects of Li_(4)Ti_(5)O_(12) nanoparticles and mesopore-oriented porosity strengthen composites with rapid Li^(+)diffusion and electron conductive frameworks.The obtained optimal LTO/GO-1.75 composite displays excellent high-rate capability(136 mA·h/g at 7000 mA/g)and good cycling stability(a capacity retention of 72%after 1000 cycles at 7000 mA/g).Additionally,the reactants concentration in this demonstrated strategy is as high as 30 wt%−40 wt%,which is over 6 times that of traditional methods with GO suspensions.It means that the strategy can significantly increase the yield,showing big potential for large-scale production.

Graphene oxide quantum dots embedded polysulfone membranes with enhanced hydrophilicity,permeability and antifouling performance

Graphene oxide(GO) has been demonstrated to be an effective hydrophilic nanofiller to modify the polymeric membranes when forming a mixed matrix structure. GO quantum dots(QDs) are promising candidates to fully exert the rich oxygen containing functional groups due to their unique size induced edge effects. In this work, GO QDs modified polysulfone(PSF) ultrafiltration(UF) membranes were prepared by phase inversion method with various GO QDs loadings(0.1–0.5 wt.%). A proper amount of GO QDs addition led to a more porous and hydrophilic membrane structure. With 0.3 wt.% GO QDs, the membranes showed a60% increase in permeability(130.54 vs. 82.52 LMH bar^-1).The pristine PSF membranes had a complete cutoff of bovine serum albumin molecules and it was well maintained with GO QDs incorporated. The membranes with 0.5 wt.% GO QDs exhibited the highest flux recovery ratio of 89.7% and the lowest irreversible fouling of 10.3%(54.5% and 33.3% for the pristine PSF membranes). Our results proved that GO QDs can function as effective nanofillers to enhance the hydrophilicity, permeability and antifouling performance of PSF UF membranes.

Synthesis and characterization of amphiphilic graphene

A simple and effective method for the preparation of amphiphilic graphene(AG)is presented under an organic solvent-free synthetic condition.The synthetic route first involves a cyclization reaction between carboxylic groups on graphene oxide and the amino groups on 5,6-diaminopyrazine-2,3-dicarbonitrile,and subsequent reduction by hydrazine.Results of UV-vis spectroscopy,Fourier transformed infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),thermogravimetric analysis(TGA)and Raman spectroscopy have confirmed that the covalent functionalization of graphene can be achieved through the formation of imidazo[4,5-b]pyrazine on the graphene sheets.As a result,AG can be successfully dispersed in water and common organic solvents.This work successfully provides a facile and efficient way to fabricate AG and may extend the potential applications of graphene-based materials in nanoelectronic devices,polymer fillers and biological field.