28 April 2012, Volume 30 Issue 12

    

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  Dietzia maris Induced by Carbon-ion Beams and Its Biodegradation Ability

  ZHOU Xiang;LIANG Jianping;LI Xuehu;LU Xihong;GUO Zhiting;HAO Baocheng

  . 2012, 30(12): 21-25. https://doi.org/10.3981/j.issn.1000-7857.2012.12.001

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  Biosurfactants have the advantages of non-toxic, biodegradable, and these properties are particularly suitable for the biological viscosity reduction of oil, oil recovery enhancement, and the bioremediation of heavy oil polluted soil. By using Dietzia maris bacteria that are the only one could produce extracellular biosurfactants in the sole carbon source medium radiated by the different doses of ¹²C⁶⁺ ion beam, a positive mutant strain YR9 is screened from the large number of mutants. The studies show that the best mutation rate of the bacteria is obtained with the 25Gy dose irradiation, resulting in surface active dose of 6336.45U/mL. Comparing with the strain without mutagenic treatment, the improvement of 2.65-fold is achieved; it almost able to completely degrade n-C₅, n-C₆, n-C₁₆, toluene, quinoline, carbazole, o-xylene, p-xylene, gasoline, naphthalene, catechol, however for n-C₅, naphthalene degradation is lower. The physical and chemical properties of the surface active agent produced by the bacteria are analyzed, its products are identified, and the condition produced surface active agent is optimized.
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  Graph Analysis for the Motor Cortical Neuron Network Post Spinal Cord Injury

  HUO Yan;LI Ping;MA Chaolin;ZHANG Hang;HE Jiping

  . 2012, 30(12): 26-31. https://doi.org/10.3981/j.issn.1000-7857.2012.12.002

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  The impact of the potential functional reorganization in neuronal populations in motor cortical areas during the functional recovery post a Spinal Cord Injury (SCI) remains unclear. In this study, the cortical neuronal data were recorded from a monkey while it was trained to walk bipedally on a treadmill both before and after the spinal cord injury. A neuronal network graph for multiple steps in different sessions was constructed by using the correlation coefficients between different neurons. The global efficiency and the vulnerability of the graph were then evaluated to reveal the intrinsic relation between the changes of the neuronal activity patterns and the functional recovery. The preliminary results indicate that the observed significant changes in the neuronal activity patterns in the motor cortex suggest that the patterns of the functional reorganization (neural plasticity) in the motor areas of the cortex are correlated and they make contributions to the functional recovery.
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  Effect of Glutathione and Analogue on High Temperature Tolerance of Wheat Seedlings

  GAO Wei;ZHANG Mingcai;DUAN Liusheng

  . 2012, 30(12): 32-36. https://doi.org/10.3981/j.issn.1000-7857.2012.12.003

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  In this experiment, glutathione (GSH), oligopeptide (GCG), and three substances including glutamate (Glu), cysteine (Cys) and gamma aminobutyric acid (GABA) were used as treatments, water was used as control (CK), two wheat (Triticum aestivum L.) seedlings Jingdu 40 and Liaochun 17 were taken to study the effects of different treatments on physiological characteristics under high temperature resistance, and furthermore to determine the physiological activity of the oligopeptide GCG. The results show that under the condition of high temperature stress, the treatments with 200μmol/L GSH and GCG are able to maintain higher leaf relative water content of wheat seedlings, reduce the relative electrolyte leakage and malondialdehyde (MDA) content, and conduce to the integrity of cell membrane. In the meantime, GCG treatment could significantly enhance the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity in wheat seedlings under high temperature stress, and the activities of antioxidative enzymes are also improved to reduce the damage caused by the high temperature. Comparing with the other two kinds of treatments, the effect of GCG treatment is most significant. On the whole, GCG could enhance the high temperature tolerance of wheat through modifying the activities of antioxidative enzymes similar to GSH. Therefore as a kind of synthetic oligopeptide, GCG is expected to develop the applications as an agricultural production regulator.
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  ¹²⁵I-NGF Induces the G₂ Arrest in Glioma U251 Cell Line

  FENG Yun;CHEN Xi;LIANG Wei;YANG Yong;ELAHI Gulshan

  . 2012, 30(12): 37-41. https://doi.org/10.3981/j.issn.1000-7857.2012.12.004

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  The DNA-damage process of the U251 cells after being treated with ¹²⁵I-NGF is observed to show the antitumor mechanism of ¹²⁵I-NGF. The cell cycle arrest and the Western Blotting analysis were adopted to display the inherent mechanism. The micronucleus test and the single cell gel electrophoresis methods were used to observe DNA-damage changes of the U251 cells. The mechanisms involve the activation of ATM and ATR pathways by ¹²⁵I-NGF, which perhaps explains some of its anticancer activities related with nuclear transportations. In a dose-dependent manner, ¹²⁵I-NGF reduces the Cyclin B1 expression protein level rather than mRNA level in human cell lines of glioma. In U251 cells, phosphorylated Chk1, Chk2 and Cdc25c protein levels are elevated, whereas p53 and p21 levels remain unchanged. In summary, this study demonstrates that ¹²⁵I-NGF plays a role in glioma cancer growth via DNA-damage, ATM and ATR activation mechanisms and multiple proteins involved in the process.
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  The Control System Design of the Wireless Remote Control Pruning Machine

  ZHANG Junmei;KE Qiuhong;LI Wenbin;YANG Kai

  . 2012, 30(12): 42-45. https://doi.org/10.3981/j.issn.1000-7857.2012.12.005

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  Automatic pruning machine is the important equipment for artificial forest pruning thinning replaced the artificial work to do the tree pruning and training. Taking the automatic pruning machine as the control object, a wireless remote control system, which is composed of the Complex Programmable Logic Device (CPLD) and a wireless data transmission module, is designed. The receiving module receives the control command, then CPLD control outputs pulse width modulation signal to drive the two servos, ensuring that the pruning machine works in the desired state. The CPLD chip used in the design is Altera Company's Zero power chip EPM240ZM100, and the receiving module used in the design is the low-power CZS-7B. The circuit has the advantages of simple structure, low power consumption. And after the actual measurement, it is found that the control system of the normal operating current is only 50mA.
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  A Drilling Fluid System for Sulfide-controlling and Sealing While Drilling

  SUN Jiewen;ZOU Honglan;DING Yunhong

  . 2012, 30(12): 46-49. https://doi.org/10.3981/j.issn.1000-7857.2012.12.006

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  The lost circulation and the sulfured hydrogen corrosion are two problems in drilling in a fractured abnormal low pressure acidic gas field. To deal with these problems, the drilling fluid system for the lost circulation while drilling-LCM is developed. The related laboratory experiments and field applications were carried out. The LCM system consists of the desulphurization agent, the inhibitor, the corrosion inhibitor and the plugging agent, and it is shown to be of stable performance, good suspension property and good compatibility. This system has been applied in three wells. The application in the field shows that it can inhibit the sulfide effectively without affecting the drilling speed in the process of drilling, and can successfully build a man-made sidewall to plug effectively for the lost circulation interval of 110m rapidly. It is shown that the LCM system can effectively inhibit the sulfide with good liner cementation and geologic logs. The system can also reduce the operation time and the drilling fluid amount, thus to reduce the operation cost and shorten the operation cycle, as well as ensure the operation quality.
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  Properties of Subdifferentials and Approximate Subdifferentials of L⁰-Valued Functions on Random Locally Convex Modules

  YANG Yujie

  . 2012, 30(12): 50-53. https://doi.org/10.3981/j.issn.1000-7857.2012.12.007

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  The random convex analysis of subdifferentials and approximate subdifferentials is carried out in this paper. Based on the analysis of the stratification structure and the recently developed separation theorems in random locally convex modules, some nice basic properties about subdifferentials and approximate subdifferentials of a L⁰-valued function on random locally convex modules are obtained. The main results are as follows. First, for a proper and T_c-lower semicontinuous L⁰-valued L⁰(F)-convex function f defined on a random locally convex module (E, Λ) where both E and Λ have the countable concatenation property, it is proven that the approximate subdifferential of f is nonempty. Second, for two propers and T_c-lower semicontinuous L⁰-valued L⁰(F)-convex functions, denoted by f and g, which are defined on a random locally convex module (E, Λ) where both E and Λ have the countable concatenation property, the formula about the subdifferentials of f+g is given.
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  An Analytical Method for Mixed Dislocation in a Simple Cubic Crystal

  ZHANG Dongbo;LI Tieping

  . 2012, 30(12): 54-56. https://doi.org/10.3981/j.issn.1000-7857.2012.12.008

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  The governing equation of Peierls-Nabarro (PN) model is very complex, and its solution is given often without any solving process, which restricts the application of the PN model. A new method is proposed to describe the propagation of a mixed dislocation in a simple cubic crystal. First, the shear stress field and the dislocation density field on the slip plane are expressed as the trigonometric series and the first Chebyshev polynomial series, respectively, and then a set of governing equations are obtained; finally, the Newton-Raphson method is used to solve the governing equations. The results show that the method proposed in this paper is simple and effective for analyzing the propagation of mixed dislocations in a simple cubic crystal.
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  Energy Consumption and Energy Potential of Miraco Bubble Aerated Oxidation Ditch & BAF and Measures of Energy Saving

  SHI Zhangming;SHEN Hao;JIANG Xinjie;CHEN Tong;YU Huang

  . 2012, 30(12): 57-61. https://doi.org/10.3981/j.issn.1000-7857.2012.12.009

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  The advanced treatment of urban sewage and the related energy consumption are issues for concern. The wastewater treatment process of miraco bubble-aerated oxidation ditch and biological aerated filter is studied in this paper, its energy consumption and the process energy potential are analyzed from the perspective of the technical process. The results show that the maximum power consumption in the process of miraco bubble-aerated oxidation ditch accounts for 54.59% in the total power consumption, followed by those in water pumping stations, sludge pumping stations and water pumping stations, respectively, which account for 13.49%, 9.56% and 8.69% in the total power consumption. The aeration system and the sewage sludge dynamic system take still the most important part in the energy consumption. The reductions of chemical energy potential and biological energy potential in the entire process are 231.6×10⁶kJ/d and 201.5×10⁶kJ/d. The potential energy in the sewage water is higher than the total energy consumption, the rates of the increase in the energy consumption and decrease in the energy potential are the greatest in the miraco bubble-aerated oxidation ditch. Some energy-saving measures are proposed for the process, the electrical equipment and the re-use of resources.
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  Advances in Electric Aircraft Technology

  ZHAO Changhui;CHEN Liwei;LU Libo;ZHANG Qinman;SUN Lu

  . 2012, 30(12): 62-70. https://doi.org/10.3981/j.issn.1000-7857.2012.12.010

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  Electric aircraft is a new type of aircraft, with extraordinary advantages of environment friendly, high efficiency, energy saving etc., which may have important impact on the future development of aviation, and a good prospect. Design methodology and techniques of electric aircraft are outlined in this paper. A brief introduction of the electric aircraft development since the 1970's is given firstly, followed by an analysis of its performance through related data, and its shortcomings. Then the conceptual design methodology of different types of electric aircraft (solar powered, battery powered, fuel cell powered, retrofitted) is summarized and analyzed in detail, together with related design tools and support systems. Specific techniques of electric aircraft design, including the aerodymanic configuration and the general layout, the electric propulsion system, the structure and the materials, are discussed finally.
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  Developing Status and Development Trend of Vertical Axis Turbine-type Tidal Current Energy Power Generation Device

  MA Yong;ZHANG Liang;MA Liang;CHEN Zhan

  . 2012, 30(12): 71-75. https://doi.org/10.3981/j.issn.1000-7857.2012.12.011

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  Energy shortage and environment pollutes aggravate ceaselessly all over the world. As a green clean pollution-free renewable energy, tidal current energy has characteristics such as large reserves, wide distribution, predictability, little environmental pollution, etc. Development and utilization of tidal energy has important practical significance to ease the energy shortage and reduce the pollution of the environment. The main form to utilize tidal energy is to generate power, this paper studies the vertical axis turbine-type tidal current energy power generation device, describes the present development situation of the power generation device which could be divided into three kinds, namely the floating structures, the seabed piled structures and the sit seabed structures, analyzes the characteristic of different structural forms of the power generation device, pointed out the development trend and key technology of the power generation device. This paper will provide reference for theory study and engineering application of the vertical axis turbine-type tidal current energy power generation device.
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  The International Working Definitions of "Nanomaterials"

  ZHANG Tianlong

  . 2012, 30(12): 76-79. https://doi.org/10.3981/j.issn.1000-7857.2012.12.012

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  There are unknown security risks and unexpected dangers when using the nanomaterials based and nanotech-enabled products. For the benefits of human health and the environment, it is necessary to conduct a risk assessment on the production and the application of nanomaterials and nanotech-enabled products. Moreover, a uniform regulation of registering the nanotech-enabled products can help supervise the nanotechnology industry. For both risk assessment and product register system, the definitions of nanomaterials are the primary requirement. Based on an overview of the existing various international working definitions of "nanomaterials", a comparison analysis is conducted with respect to size, internal structure, physical and chemical characteristics. So far, seeking an inclusive size range and using a hierarchical approach are two significant methods to define the nanomaterials. However, neither approaches actually address the associated uncertainties when the definitions of "nanomaterials" are requested for the use as "enforceable terms" in a specific regulatory setting. A more detailed regulatory definition should be introduced for supervision. The other factors included in the definition must apply to all nanomaterials.