Automatic evolutionary modeling by the Lattice-Boltzmann method

The Lattice-Boltzmann method is an effective tool for solving fluid mechanics problems, but there isn’t still a good scheme to determinate some parameters in Boltzmann equations. In this paper, a technique using evolutionary algorithm to automatically model Boltzmann equations is introduced. Numerical simulation shows that the designed scheme is fast and efficient. Biography: Chen Ju-hua ( 1963-), male, Associate professor, research direction: Lattice-Boltzmann method, evolutionary algorithm.     

A preliminary study of crassulacean acid metabolism (CAM) in the endangered aquatic quillwortIsoetes sinensis Palmer in China

Isoetes sinensis Palmer (Isoetaceae) is an aquatic or amphibious plant that is critically endangered in China. Previous studies have revealed the crassulacean acid metabolism (CAM)-like photosynthetic pathway occurs commonly in submerged leaves in genusIsoetes. Water chemistry parameters and the titratable acidity content of the plant extract were measured from samples obtained in the early morning (7∶00) and late afternoon (15∶00) from twoI. sinensis populations in China. One population occurs in the eulittoral zone of a freshwater tidal river at low elevation (134 m) and another occurs in a densely vegetated, high elevation (1 100 m) alpine shallow pool. Significant differences in pH and titratable acidity of the plant extract were detected between the morning and afternoon samples. These changes are associated with diurnal changes in water chemistry. Our results provide the first evidence for the existence of the CAM pathway in the East Asian endemicIsoetes sinensis Palmer. The magnitude of fluctuations in the titratable acidity of the plant extract may be correlated with the severe carbon limitation imposed on the plants by its aquatic habitat. Foundation item: Supported by the State Key Basic Research and Development Plan (G2000046805) Biography:Pang Xin-an (1974-), male, Master candidate, research direction: conservation biology.     

Stress corrosion cracking and its anisotropy of a PZT ferroelectric ceramics

It is known that some types of ceramics, like Al2O3 and ZrO2, undergo stress corrosion cracking (SCC) or static fatigue fracture under static loading, ever in a rela-tively mild environment, such as moist atmosphere or water at room temperature, which leads to a time-dependent fracture[1—4]. For a transmission electron microscopy specimen of YBa2Cu3O7-x ceramics superconductor, SCC induced by residual stress can occur in an atmosphere with low moisture content[5]. For a lead zirconate ti…     

Do multiple cycles of aeolian deposit-pedogenesis exist in the reticulate red clay sections in southern China?

Since the Quaternary scientists successfully dis-closed the paleoclimatic significance of the loess-paleo- sol sequence in the Loess Plateau, Northwest China, the loess-paleosol sequence has become well-known terres-trial materials revealing the multiple cyclic changes of Quaternary climates. As a carrier of paleoenvironmental information, it could compare beauty with the deep ocean deposit[8]. In recent years, however, the researchers began to put their sights to southern China. They try t…     

The age of formation of the mirabilite and sand wedges in the Hexi Corridor and their paleoclimatic interpretation

The Hexi Corridor is located at the transition zone of the Asian summer monsoon and westerly airflow, and lies in an important position in terms of its ecological fragility and climatic sensitivity. During a recent field expedition to this region, we found a sedimentary mirabilite layer in a number of localities including Suwushan, Yanchi, Baitujing, Yanchi Gaotai, Huahai, Yumen, Halanuo扙r, and Dunhuang (Fig. 1), which have the potential to provide important information about environmenta…     

Temperature variations on the Tibetan Plateau over the last two millennia

The paleoclimate data recovered from ice cores,tree rings and lake sediments indicate regional features of cfimatic change on the Tibeta n Plateau (TP) during the last 2000 years. The composite temperature reconstructions in-dicate that several main climatic episodes, such as the “LittleIce Age“ between 1400 and 1900, the “Medieval Warm Pe-riod“ in 1150-1400, a less warm period in 800-1100, and an earlier cold period between the 3rd and 5th centuries,occurred in the TP. In addition, temperature varied from region to region. The period from AD 800 to 1100, which waswarm in northeastern TP, was contemporaneous with cool-ing in the western and southern TP. The southern TP ex-perienced warming between 1150 and 1400. For western TP,the δ^18O records of the Guliya ice core indicate that the pe-Hod 1250-1500 witnessed a clear warming. Large-scaletrends in the temperature history from northeastern TP aremore similar to those in eastern China than are the trendsfrom the Guliya ice cap far to the west and southern TP. The most prominent similarities between the temperature varia-tions of the TP and eastern China are such cold phases as 1100-1150, 1500-1550, 1650-1700 and 1800-1850, andthe latter three cold events match with three widespreadg lacial advances which occurred on the TP during the Little Ice A2e.     

Time-division phase modulated single-photon interference in a Sagnac interferometer

We introduce a stable, long-distance singlephoton Sagnac interferometer, which has a balanced configuration to efficiently compensate phase drift caused by change of the fiber-optic path. By using time-division phase modulation, single-photon interference was realized at 1550nm in a 5-km-long as well as 27-km-long Sagnac fiber loops,with a fringe visibility higher than 90% and long-term stability. The stable performance of the single-photon interference indicated that the time-division phase-modulated Sagnac interferometer might readily lead to practical applications in single-photon routing and quantum cryptography.     

Expression of human clotting factor Ⅸ mediated by recom- binant lentiviral vector in cultured cells and hemophilia B mice

To explore the expression of human clotting factor Ⅸ (hFⅨ) cDNA in vitro and the feasibility of gene therapy for hemophilia B mice mediated by recombinant lentiviral vector, a recombinant hFⅨ lentiviral vector driven by ubiquitin-C promoter, FUXW, and by ABP liver specific promoter, FAXW, was constructed respectively. Recombinant lentivirus was harvested from 293T cells by calcium phosphate-mediated transient cotransfection of three plasmids (transgene vector, CMV腞8.2, VSV-G). hFⅨ expression was detected in supernatant of 293T, BHK and L-02 cells infected with FUXW virus, whereas higher expression of hFⅨ levels (630 ng/106 cells/48 h) was detected only in L-02 cells infected with FAXW virus. Serum hFⅨ antigen was detected in all hemophilia B mice treated with FAXW virus by tail vein injection, an efficiency level of hFⅨ was observed (45 ng/mL, approximately 1% of normal human levels), the expression lasted for more than 60 d. The results indicated that HIV-based lentiviral vectors offer a promising approach to the gene therapy of hemophilia B.     

鄂尔多斯盆地低渗透油田注水开发的调整与优化

根据鄂尔多斯盆地成功开发的主要特低渗油田——安塞、靖安、华池油田长6、长3油层的储层特征及开发实践,提出了改善特低渗油田注水开发效果的注采参数、注水方式优化及调整技术,从而达到提高单井产量及最终采收率,降低开发投资和生产成本,以提高整体开发效益的目的.