08 November 2011, Volume 29 Issue 31

    

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  Spatiotemporal Distribution and Controlling Factor of the Late Paleozoic Zoophycos in South China

  ZHANG Lijun;GONG Yiming

  . 2011, 29(31): 18-28. https://doi.org/10.3981/j.issn.1000-7857.2011.31.002

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  Through studying on Zoophycos from three Late Paleozoic sections (the Dahekou Devonian section, the Ercengpuo Carboniferous section, and the Dongpan Permian section) and summarizing the previous related literatures on the Late Paleozoic Zoophycos in South China, the Zoophycos from these regions represent the complex spreiten with well-preserved major and minor lamellae, and consist of marginal tube and cylindrical tunnel. A systematic investigation of morphology and palaeoenvironment of Zoophycos is carried out. The study indicates that (1) both the spiral-like and tougue-like Zoophycos are identified. (2) Zoophycos are mainly distributed in the Early-Middle Devonian (Emsian-Eifelian), Mississippian (Visean), and Guadalupian (Wordian); and mainly occur in the southeast of Guizhou Province, central-southern of Hunan Province, and northeastern of Guangxi Province, and are abundant in a condition with a lower energy and soft substrate from shoreface to subtidal shelf. It seems that the spatiotemporal distributions of the Late Paleozoic Zoophycos in South China are coupled with the Late Paleozoic evolution of atmosphere oxygen (17%—24%), climate and temperature (20—25℃), seawater geochemical compositions (calcite seas, Mg/Ca<2), and mass biological extinction events.
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  Relationship Between Fold-thrust Belt Tectonic Deformation and Transverse River

  YANG Fu;CHEN Gang;DING Chao;MAO Xiaoni;LI Nan;LI Yan

  . 2011, 29(31): 29-33. https://doi.org/10.3981/j.issn.1000-7857.2011.31.003

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  The relation between tectonic deformation and surface process is a research front in recent years. European geologists study on the relationship between tectonic deformation and surface process and make some new progress, especially a coupling relationship between fold thrust belt deformation and surface processes at the smaller length scale. It has altered the traditional concept that tectonic deformation effects on surface processes with one-way control, and the new idea that the transverse river cutting could influence anticline deformation style is put forward. Deformation is influenced by surface processes and terrain slope (tectonic deformation), and there is a two-way coupling between the transverse river cutting and anticline deformation. The research with a numerical model shows that surface processes (mainly fluvial) effect deformation folding through the distribution change of the overlying material weight. Anticline deformation styles are not strongly influenced by lateral erosion of river incision. In order to study the interplay between structure deformation and transverse river at the piedmont region, it should not only consider the influence of tectonic deformation on the river, but also take the active role of river incised erosion, as well as climate factors into account. Therefore, the results provide a new thinking for basin and mountain coupling dynamics.
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  Prediction Method for Fast and Iteration-free Shear Wave Velocity Based on Approximated Fluid Substitution

  HOU Bo;CHEN Xiaohong;ZHANG Xiaozhen;LIANG Donghai;

  . 2011, 29(31): 34-37. https://doi.org/10.3981/j.issn.1000-7857.2011.31.004

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  The information on shear wave velocity is insufficient in realistic well logging data, even though shear wave velocity plays an important role in the reservoir characterization and fluid identification. Therefore it has become an important part of rock physics research to predict shear wave velocity (V_s). Empirical regression equations are based on water saturated rock; therefore, the fluid of hydrocarbon saturated rock must be substituted by water before shear wave velocity prediction. Using fluid substitution without shear wave velocity to predict longitudinal wave velocity (V_p) of water saturated rock, the drawback that traditional fluid substitution needs shear wave velocity for the prediction is overcome. By employing V_p-V_s regression equations of water saturated rock, reservoir shear wave velocities with water saturation are predicted. Furthermore, by using density correction, shear wave velocities of reservoir saturated by hydrocarbon are obtained, and then the method for predicting fast shear wave velocity without iteration is established and is applied to shear wave velocity prediction of realistic well logging data. The results demonstrate that prediction precision of the method proposed is obviously higher than that without fluid substitution, and fast shear wave velocity prediction method without iteration is effective.
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  Finite-element Analysis on the Bar Scatters Regular Pattern of Discrete Rod Warheads

  LI Wei;LIU Ying;JIANG Zhihai;ZHENG Yuanfeng;HU Rongxi

  . 2011, 29(31): 38-42. https://doi.org/10.3981/j.issn.1000-7857.2011.31.005

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  The rod arrangement and scatters way for the discrete rod warheads are in-depth studied in terms of theory, numerical simulation, and experiment. By using AUTODYN-3D software, the three-dimensional finite element model of the discrete rod warheads has been established. Through Lagrange algorithms, the steel rod and the tungsten carbide rod of the discrete rod warheads with or without filling materials are simulated. It is found that the rod material and the cushioning material have a significant effect on the rod scatters behavior, Loading appropriate buffer materials is in favour of reducing the fly of detonation products and improving the energy utilization ratio of explosives. The theoretical analysis might provide some useful reference for the design of the discrete rod warhead.
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  Electric Field Sensitive of Poly(AM-Co-DMDAAC) Hydrogels

  LIAO Liewen;XIAO Linfei;YUE Hangbo;GONG Tao

  . 2011, 29(31): 43-47. https://doi.org/10.3981/j.issn.1000-7857.2011.31.006

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  In order to study the electric field sensitive of cation character DMDAAC hydrogels, Acrylamide/Dimethyldiallylammonium chloride (AM/DMDAAC) hydrogels are prepared by free radical copolymerization in aqueous solution in the presence of N,N methylene bis (acrylamide) (MBAAm) as the crosslink agent, ammonium per sulfate and sodium bisulfite as the redox initiator. Deswelling kinetics and bending behaviors of the sample hydrogels under electric stimulus are illustrated. It is found that monomer amount of DMDAAC, the time as well as the size of applied voltage, and the ion intensity of solution have a favorable impact on the electric sensitive properties of the AM/DMDAAC hydrogels. It might have applications in chemical valve and bionic actuator. Hydrogels display a bending toward anode in NaCl solution of low chroma. The bending toward anode is depressing along with NaCl chroma increasing. Hydrogels show a bending toward cathode in NaCl solution of high chroma. The banding angle of hydrogels is affected by the critical chroma of NaCl from 0.3% to 0.4%. Since these hydrogels are made up of different monomer content, the critical chroma of NaCl is also different.
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  Sluggishing Dust and Disinfection of Typical Green Plants in Anshun City Proper

  ZHANG Lai;ZHANG Xianqiang

  . 2011, 29(31): 48-53. https://doi.org/10.3981/j.issn.1000-7857.2011.31.007

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  The garden greening as a subsystem of the urban ecosystems beautifies the urban environment; it plays an active role for maintaining urban ecological balance and sustainable development. On the basis of surveying the green plants in Anshun city proper, the capability of sluggishing dust and disinfection involving typical plants is studied, and results show that the plant species is few, structure is unitary, species evenness is low; in terms of the index of leaf area, the order is the arbors, climbing plants, flowers and herbs, and shrubs one by one. With the time increasing, the capability of sluggishing dust is increasing for different green plants. Among them, the strongest is Rhododendron simsii that the capability of sluggishing dust reaches 6.6298g/(m²·week) four weeks late, compared with 3.3376g/(m²·week) in the end of the first week, it increases nearly two-fold; the second place belongs to Pinus massoniana, it is up to 5.7413g/(m²·week); the last place belongs to climbing plants. For the open area, the bacterial number is significantly more than that for the plant areas, 11 species of them including Cinnamomum camphora have strong bactericidal effects, their sterilization rates are above 40%.
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  Numerical Simulation of Soil Moisture Variation on Climate

  GUO Yana;PAN Yinong

  . 2011, 29(31): 54-58. https://doi.org/10.3981/j.issn.1000-7857.2011.31.008

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  Water resource appears the serious region difference between southern and northern part of China. The northern part belongs to the dry region which water is hard up; however, the supply exceeds demand that is the character of water resources in the southern part. Along with the economical development and the climatic fluctuation, the contradiction between the supply and demand for water resource in the northern part is gradually becoming serious, since 1980s. The trend of climatic fluctuation is represented by the decreasing precipitation and increasing temperature. The economical loss and the environmental degeneration become more obvious than ever before. The drought affects people's life and work seriously. Water transportation from south part to north part of China is a valid measure to resolve this problem. Through water transportation from south to north part of China, the contradiction involving water shortage could be solved. It could improve environment and accelerate the speed of social development. The change of soil moisture that influences on the local environment of meteorology is researched. The mode of MM5 is used to simulate, and the Oregon State University Land Surface Model(OSULSM)is selected as the land surface mode. It could be found that for the different seasons, with same amount of the initial soil moisture increasing, there is different range of increasing on the seasonal average soil moisture, and it is corresponding with the different range of changing on the precipitation and the ground temperature. For different seasons, with the same variety of soil moisture, the change is larger in the summer than that in the spring in terms of precipitation and the ground temperature.
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  Determination of FHIT and CDKN2A Promoter Methylation Levels in Hazak's Esophageal Cancer Tissue Based on Methylation-sensitive High Resolution Melting Analysis and Its Clinical Significance

  LI Hui;LIU Ling;WANG Hongjiang;CHEN Yan;PANG Zuoliang;JIANG Xiaofang;WU Jun;LI Xiumei;MA Lili;ZHOU Bo;LI Huiwu

  . 2011, 29(31): 59-63. https://doi.org/10.3981/j.issn.1000-7857.2011.31.009

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  The promoter methylation of tumor suppressor gene is one of the most important mechanisms of tumorigenesis. The method of Methylation-Sensitive High-Resolution Melting-curve (MS-HRM) analysis was used to analyze methylation differences at the FHIT, CDKN2A locus in DNA samples from individuals with Esophageal Cancer (EC) (n=30) and adjacent normal tissues (n=30). After extracting and modifying DNA by methylating-agents, the standard DNA samples were mixed with the completely methylated DNA to make the dilute methyled DNAs of 0%, 5%, 25%, 50%, 75%, and 100%, respectively. And then their sensitivity and repeatability were evaluated. Using HRM, the methylation level was detected. And the relation between the methylation levels of FHIT and CDKN2A promoters and the development of EC is discussed. The high-resolution melting-curves of 100%, 80%, 50%, 30%, 10%, and 0% methylated DNA are decreasingly arranged from right to left, the locations on the standard curve denote the methylation level. The lowest detection limit of HRM is 1%, and it is more sensitive than the 10% detection limit of MSP. With the MS-HRM assay, 36.7% of the FHIT promoters (11/30) are methylated. Among them, there are eight cases with methylation level between 0%—5%,and three cases with methylation level between 5%—10%. 100% of the CDKN2A promoters (30/30) are methylated. There are seven cases with methylation level between 0%—5%, 11 cases with methylation level between 5%—10%, and 12 cases with methylation level between 10%—25%. Compared with the adjacent normal tissues, there is no significant relationship between the methylation and the development of the Hazak's EC. There is no significant relationship either between the methylation and the TNM or between methylation and differentiation of two genes in the Hazak's esophageal cancer. It is found that the MS-HRM is a simple, rapid, and robust method for screening methylation differences at the FHIT, CDKN2A locus; furthermore the more suppressor genes will be screened and found as the early diagnostic markers.
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  Statistics and Analysis of Abstract Information Included in Chinese Science Abstracts (Chinese Edition) in 2010

  XU Bing;LIU Yuanmin;ZHANG Baoqing;TANG Zhen;WANG Shuaishuai

  . 2011, 29(31): 64-69. https://doi.org/10.3981/j.issn.1000-7857.2011.31.010

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  Based on the statistics of 396 scientific and technical journals indexed by Chinese Science Abstracts(Chinese Edition) in 24 issues published in 2010 including 48534 abstracts, this paper analyzes the academic levels of the source journals, the geographical distribution of author's working places, the distribution of author's affiliations and research fields, which can reflect the scientific research capacity and the academic level of different regions and institutions to some extent, and the results are compared with those in 2009.
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  Cordierite Honeycomb Ceramics Used for Purification of Vehicle Exhaust

  WANG Wei;WU Xiaodong;WENG Duan;HUANG Feihui;PAN Jiqing

  . 2011, 29(31): 70-74. https://doi.org/10.3981/j.issn.1000-7857.2011.31.011

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  Cordierite honeycomb ceramic is one of key materials for vehicle exhaust purification as a support material in catalytic converters and diesel particulate filters, owing to its superior thermal and mechanical properties. In view of more and more stringent emission standards, the improvement of cordierite honeycomb ceramic becomes an important issue, especially in product specifications and performances. The extrusion method of cordierite honeycomb is reviewed in this paper with focuses on the process choice, raw materials specifications and impurity elements. In the context of the huge market demand for cordierite honeycomb ceramics, some key problems are discussed, including the possible routes to improve the product quality and the challenge of the international competitiveness.
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  Research Progress on Antitumor Effect of Polyoxometalates

  GAN Qiang;LIU Xia;FENG Changgen

  . 2011, 29(31): 75-79. https://doi.org/10.3981/j.issn.1000-7857.2011.31.012

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  Polyoxometalates have attracted much attention in the field of medicine because of their good bioactivities, including antitumor, antibacterial and antivirus activities. With its unique characteristics in structure, polyoxometalates could be modified by introducing different types of organic or inorganic groups into their structure, to improve their stability and bioactivity. The synthesis of new polyoxometalates with high bioactivities and low toxicity is an issue widely studied. This paper reviews studies of polyoxometalates derivatives, the antitumor mechanism and the biological effects of polyoxometalates in recent years. Organic and organometallic derivatives have remarkable antitumor activities against several types of tumor cells. According to the oxidation-reduction theory, the antitumor activity of polyoxometalates is related with the oxidation-reduction property of polyanions, and the theory is well supported by many evidences. However, the nucleic acid degradation effect observed in the in vitro implies that polyoxometalates could suppress tumor growth by the interaction with DNA or RNA. Moreover, it is found that polyoxometalates have effects on apoptosis, autophagic cell death and the immune system in the process of tumor inhibition, where the apoptosis effect plays an important role in the antitumor activity of polyoxometalates.