28 August 2011, Volume 29 Issue 24

    

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  Corrosion Behavior and Law of Copper-Clad Laminate with Immersion Silver Layer in Salt Spray Environment

  XIAO Kui;ZOU Shiwen;DONG Chaofang;WU Junsheng;LI Xiaogang

  . 2011, 29(24): 25-28. https://doi.org/10.3981/j.issn.1000-7857.2011.24.001

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  The corrosion behavior of Copper-Clad Laminate(CCL) with immersion silver layers in the neutral salt spray environment is studied by Electrochemical Impedance Spectroscopy(EIS). The surface morphology and the composition of corrosion products were analyzed by the SEM/EDS surface analysis methods. The results indicate that the immersion silver layers can protect the products in the salt spray environment. On the sample surface, no obvious corrosion could be seen in the initial stage and large impedance values were measured. But local damages would occur in the immersion silver layers due to the chlorides on the sample surface. The impedance values decrease with the test time. For a long salt spray test time, the immersion silver layers cannot effectively prevent corrosion reactions. The increase of the impedance values is due to the continued thickening of the copper rust layers, which prevent the incursion of harmful ions and the further corrosion of matrix.
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  Homoacetogens and Hydrogen Consumption in Anaerobic Activated Sludge Bio-hydrogen Production System

  LI Jianzheng;XU Yiping;ZHANG Liguo;BAN Qiaoying

  . 2011, 29(24): 29-32. https://doi.org/10.3981/j.issn.1000-7857.2011.24.002

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  The impact of homoacetogenesis on the fermentative hydrogen production of the anaerobic activated sludge in a Continuous Stirred-Tank Reactor (CSTR) is investigated by batch cultures. The predominant species in the sludge are identified with the technique of Poly-merase Chain Reaction-Denaturing Gradient Gel Electrophoresis(PCR-DGGE), and it is indicated that the homoacetogen Eubacterium exists in the activated sludge in a remarkable dominance. The hydrogen conversion rate of glucose and the specific hydrogen production rate by the activated sludge in terms of Mixed Liquor Volatile Suspended Solids (MLVSS) are reduced by 31% and 34%, respectively, due to the etabolism of the homoacetogens in the activated sludge. The hydrogen consumption rate of the homoacetogens in the activated sludge reaches 0.33 mmol/(g·d).
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  Synthesis of Water-absorbent Resin from Calcium Lignosulfonate

  LIN Jian;ZHENG Xiaoguang;ZHANG Ming

  . 2011, 29(24): 33-36. https://doi.org/10.3981/j.issn.1000-7857.2011.24.003

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  Calcium Lignosulfonate(CL), with its good performance and cheap price, is widely used as a water reducer. But CL as a superabsorbent resin additive is not well studied. CL super absorbent resin is a kind of new macromolecular network polymer materials, containing hydrophilic groups, which could absorb a large amount of water. This paper studies its preparation process, morphology and structural characterization, and the application in soil. The synthesis of CL superabsorbents is presented. The influence of several factors on absorbency is discussed: the component of CL, the type and amount of initiator, the type and amount of crosslinker, the amount of acrylamide, the neutralization degree, and the drying conditions. Using the single-factor method, the optimum process parameters in this experiment system are obtained (in wt%): acrylic 58.5%, acrylamide 19.5%, calcium lignosulfonate 5.85%, initiator 0.39%, cross-linker 0.19%, and neutralization 15.59%. The copolymers are characterized by IR spectosocopy, thermal analysis and Scanning Electronic Microcopy(SEM). It is shown to have a good thermal stability, and the components of comonomers influence the resin's decomposition temperature and surface morphological characterization notably.
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  Kinetics of Cr(VI) Removal from Aqueous Solution with Nanoscale Zero-Valent Iron

  FENG Jingwei;LIANG Chenghua;WANG Li;ZHANG Xianlong;ZHANG Siyang

  . 2011, 29(24): 37-41. https://doi.org/10.3981/j.issn.1000-7857.2011.24.004

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  A new type of environmental materials, the Nanoscale Zero-Valent Iron(NZVI), was synthesized in aqueous solutions by reduction of Fe³⁺ with NaBH₄ in order to develop a new technology to control or remediate the polluted water containing Cr(VI). The characterization with X-Ray Diffraction(XRD) and Scanning Electron Microscopy(SEM) indicates that the prepared NZVI particles are uniform in distribution and small in diameter with high purity. In the batch removal of Cr(VI) from simulated wastewater, the influences of initial Cr(VI) concentration, temperature and NZVI loading on Cr(VI) reduction on the surface of the NZVI are studied. It is found that each gram of NZVI could remove 198.02 mg of Cr(VI) from the simulated wastewater containing 30.0mg/L of Cr(VI) with an initial pH of 6-7 at room temperature. The kinetics of the Cr(VI) removal is found to follow the pseudo-second-order rate equation. The study reveals that Cr(VI) can be efficiently removed by means of absorption of NZVI in the solution and the key to achieving a high removal rate lies in the appropiate handling of factors involving initial concentration of Cr(VI) and iron loading. The reduction rates are increased with the increase of temperature and iron loading but decreased with the increase of initial Cr(VI) concentration. The experimental data show that the NZVI is very attractive for the removal of Cr(VI) from wastewater.
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  Relationship Between Changes of Prethrombotic State with Coronary Heart Diseases and Traditional Urgur Medicine Syndromes

  AIZEZI Renaguli;WUSHUER Palidan;ABUDOUREYIMU Shajidan;JIN Wei;UPUR Halmurat

  . 2011, 29(24): 42-46. https://doi.org/10.3981/j.issn.1000-7857.2011.24.005

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  To investigate the relationship between changes of prethrombotic state with coronary heart diseases and traditional Urgur medicine syndromes on coronary heart diseases. 245 patients with coronary heart diseases were randomly selected and then grouped according to the traditional Urgur medicine theories. The expression of CD62p on platelets, the level of plasma tissue Plasminogen Activator (t-PA), the level of Serum Endothelin (ET-1), the Activated Partial Thromboplastin Time (APTT), the Fibrinogen (FIB), the Nprothrombin Time(PT), and the Thrombin Time(TT) were determined by flow cytometer, enzyme-linked immunosorbnent assay,radioimmunoassay method, and auto coagulometer. Compared to the control group, the levels of CD62p, FIB, PAI and ET-1 are increased in the abnormal savda group and the non-abnormal savda(abnormal khan, abnormal sepra and abnormal belghem)group (P<0.05); the level of t-PA is decreased in the abnormal savda group and the non-abnormal savda group (P<0.05); the APTT and PT are shortened in the abnormal savda group and the non-abnormal savda group (P<0.05), There are no significant changes of CD41 and TT in all groups (P>0.05). Compared to the abnormal savda group, the level of ET-1 is increased in the abnormal khan and abnormal sepra group(P<0.05), the level of CD62p is increased in the abnormal belghem group(P<0.05),there are no significant differences of the levels of CD41, t-PA, PAI-1, PT, TT and APTT in patients with different traditional Urgur medicine syndrome groups (P>0.05). There is the prethromboitic state in all different Urgur abnormal syndrome groups of coronary heart diseases, which can be observed in the injury of vessel epithelial cells, increased platelet activity, increased blood viscosity, decreased fibronolytic function. The prethromboitic state of the abnormal savda syndrome group with coronary heart diseases is more obvious than other abnormal syndrome groups.
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  A Novel Classification Method for the Tight Sandstone Reservoir

  WANG Lichang;WANG Zhizhang;TAO Guo

  . 2011, 29(24): 47-50. https://doi.org/10.3981/j.issn.1000-7857.2011.24.006

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  Reservoir classification is one of the important parts of the study involving oil and gas exploration and development. Engineering data indicate that reserves of tight sandstone reservoir account for a large proportion of the total reserves in low permeability reservoirs, therefore it is meaningful to work on the tight sandstone reservoir classification. Considering the specialty and various kinds of parameters of the tight sandstone gas field of Xinchang Xu-2 formation in the west part of Sichuan Province, the four parameters, that is, porosity, permeability, flow unit, and shale content are selected as reservoir parameters, and the K-means clustering method is used to divide the formations into five categories. On basis of this, by comparing the accuracy of the discriminant analysis with that of decision tree, the decision tree classification method is used to build the quantitative evaluation of the reservoir model. It is proved by the actual data that decision tree has a better result for enhancing the effect of reservoir classification and evaluation.
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  Detection and Classification of High-frequency Cycles in the S3 Sand Member of Shanshan Oil Field, Xinjiang

  QIU Yubo;YI Haisheng;ZHANG Jun;WEN Jun;WU Chihua

  . 2011, 29(24): 51-56. https://doi.org/10.3981/j.issn.1000-7857.2011.24.007

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  In an oilfield, the sublayers, sedimented at the same time, are the elementary units of its oil/gas development, as well as the main body of the sedimentary cycles of the reservoir bed. In the classification and correlation of sublayers, a sand body in the reservoir is usually taken as the reference. But the distribution of sand bodies in a strata space is often variable, which increases the uncertainty of the classification of sublayers. In this paper, the natural GR curves are used and the method of the evolutive spectral analysis is applied. Through the comparative analysis of several wells in Shanshan oil field, 6 cycle boundaries and 5 high-frequency cycles are identified in the S3 Sand Member of Sanjianfang Formation. The appearance of cycle boundaries is consistent with the abrupt interface of the cyclic wavelength peak in the frequency spectrum. The cyclic wavelength is found to be controlled by the sedimentation rate, but has not direct relation with the lithological change and the appearance of the sandbody. So this method can be used to deal with the classification of oil layers marked by lithology. The thicknesses of these cycles range between several meters and ten or more meters. They are very close to the cycle scale of a sublayer, and these cycle boundaries detected by an abrupt change of the sedimentation rate are isochronous in the regional geologic domain. These high-frequency cycles can also be laterally compared and be considered as an important geologic parameter and a criterion in the classification and the correlation of sublayers in the oilfield development.
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  Analysis of the Fractal and Sample Size Effects of the Rock Joint Surface Roughness

  CAO Ping;LUO Lei;LIU Taoying;ZHANG Ke

  . 2011, 29(24): 57-61. https://doi.org/10.3981/j.issn.1000-7857.2011.24.008

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  The surface roughness of rock joints is a major factor that influences the rock mass deformation, displacement and strength. So its determination is very important for the evaluation of rock mechanical properties. The rock joint surface may be assumed to have fractal characteristics, and its fractal dimension can be used to describe the roughness of the surface joints, but the surface roughness of rock joints generally does not strictly have the nature of fractal self-similarity, so, the measurement results of surface fractal parameters (fractal dimension D and the intercept A) would be affected by the scale. In this study, the 3-D superficial laser topography instrument was used to scan samples of 10 different sizes (ranging from 100mm×100mm to 1000mm×1000mm ). It is shown that both the fractal dimension D and the intercept A are indeed scale-dependent, but the scale effect and their values decrease with the increase of the size of the sampling windows, and a limit size exists. Considering the rock surface size, the sample length and the measurement scale on the rock joint surface roughness, an acceptable solution for fractal measurements is proposed to assess the properties of rocks.
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  Laboratory Study of Water Locking Damage Under Imbibition in Volcanic Gas Reseroirs

  GUO Hekun;LI Taiwei;LI Haibo;LIU Jiankun;XUE Xiaojia

  . 2011, 29(24): 62-66. https://doi.org/10.3981/j.issn.1000-7857.2011.24.009

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  Water locking happens widely in volcanic gas reservoirs. and will seriouly affect the reservoir development. Based on the lab experiments combined with the NMR technology, the damage degree and the damage mechanism under the spontaneous imbibition condition are studied, and the water lock removal process in volcanic gas reservoirs is simulated by the gas flood experiment. It is shown that the water saturation due to the spontaneous imbibition is not linear with respect to the imbibition time, the saturation in the cores is increased dramatically in the first 2h from the time when the imbibition begins, after 16 hours the spontaneous imbibitions are stopped and the saturation remains almost unchanged. Applying the NMR technology to the relation between the water absorption and the pore structure, it is found that the more complex the pore structure, the larger the amount of the water imbibitions will be. The gas is used to draw the water from the cores, and it is discovered that with the increase of the pore volume, the water saturation and the damage rate due to the water locking decrease and they tend to be in moderate levels, the water lock damage is basically avoided after 25 pore volumes are driven by gas. To overcome the drawbacks of the evaluation methodology in water blocking, an improved method, the dynamic evaluation method in water blocking, is proposed.
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  Numerical Simulation of Diffusion of Unsymmetrical Dimethylhrazine Under Storage Condition

  HUANG Zhiyong;LUO Feng;SHI Huiwei;WANG Xuanjun

  . 2011, 29(24): 67-70. https://doi.org/10.3981/j.issn.1000-7857.2011.24.010

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  This paper studies the diffusing characteristics and the concentration distribution of unsymmetrical dimethylhydrazine (UDMH) released on the ground and formed into a pool under the storage condition due to some causes. The change process of concentration of UDMH evaporated from the pool on the ground is numerically simulated with Fluent software by the Computational Fluid Dynamic (CFD) method. The movement of the storeroom-air and the space-time distribution characteristics of the concentration of UDMH evaporated continually under some specified aeration conditions are studied. It is shown that the effect of gravity on the dispersion is significant; under the condition of air exhaust by devices and air intake by subatmospheric pressure, the storeroom-air moves in cycles; high concentration areas are mainly under the air intake where the speed of air is low; in the cutter tip of z axis, UDMH is distributed in circles. These results can provide some food of thought for accident disposal.
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  Study and Implementation of Wireless Sensor Networks' Trust Collaboration based on Bio-inspired Trust and Reputation Model

  MENG Jing;LIU Shouqiang;

  . 2011, 29(24): 71-76. https://doi.org/10.3981/j.issn.1000-7857.2011.24.011

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  Wireless sensor networks are usually deployed in the non-controlled environment without maintenance, facing problems of a general disclosure of information, information tampering, replay attacks, denial of service and other threats, and also facing the threat of the mass nodes being easily targeted by physical manipulation, with the information stored in the sensor nodes being taken and used for the manipulators to control a part of the network. Based on the studies of the collaboration of the ant colony system, a trust model based on biologically inspired (BTRM) trust in the cooperation mechanism is proposed for the use in wireless sensor networks. Some trust models of collaboration curently in use are analyzed, and a wireless sensor network based on BTRM collaborative trust simulation software features and software architecture is proposed. The principles and the implementations of the collaborative trust simulation system are discussed. The simulation shows the output average path length, the average satisfaction, the average deviation, which indicates an improved performance.
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  Comparison Between IPv4 and IPv6 and Transition Strategy

  WANG Hongzhi;SHANG Zunyi

  . 2011, 29(24): 77-79. https://doi.org/10.3981/j.issn.1000-7857.2011.24.012

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  With the rapid development and popular use of the Internet, the network applications, the network services and the network requirements become important issues. The resource of IPv4 addresses is dwindling now to the limit of exhaustion, at the same time, the inherent shortcomings of IPv4 are very obvious: running out of address resources, slow network speed, poor mobility, poor quality of service and low security, so IPv4 cannot meet the requirements of the rapid Internet development. On the other hand, IPv6 shows great advantages in performance in many aspects such as full address resources, high quality of service, convenient mobility, strong ability of automatic configuration and high security; The transition from IPv4 to IPv6 is an inevitable trend of the Internet's further development. Through the strategy of dual-stack, tunneling and NET-PT conversion, the IPv6 pilot and application will be vigorously promoted, and IPv4 will be gradually upgraded and transited to IPv6. It will lay the foundation for the better development of the Internet.