13 July 2015, Volume 33 Issue 13
    

  • Select all
    |
    Articles
  • Synthesis and Al3+ sensitized luminescence of green-yellow emitting phosphor LiZnPO4:Mn2+, Al3+ for LED
    NONG Rong, HUANG Yingheng, LU Ke, LIAO Sen, TAN Hongyu
    Science & Technology Review. 2015, 33(13): 13-16. https://doi.org/10.3981/j.issn.1000-7857.2015.13.001
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    A series of Li1-xZn0.9-xPO4:Mn0.1, Alx phosphors are prepared by the solid-state method to obtain a new green-yellow phosphor that can be applied for the light emitting diodes (LED). XRD results confirm that the samples contain LiZnPO4 phase of crystals. Photoluminescence properties of the samples are characterized with photoluminescence of excitation (PLE) and emission spectra (PL), and the effect of Al3+ doping on the PL and PLE properties of Li1-xZn0.9-xPO4:Mn0.1, Alx phosphors is discussed. The results indicate that the dependent curve of relative intensity for PLE and PL on Al3+ doping concentration is a parabola curve with mouth downward and maximum value, and the optimal molar concentration of Al3+ for the samples is 3%,with corresponding sample being Li0.97Zn0.87PO4:Mn0.1, Al0.03. The research results indicate that the peak area of emission bands of Li1-xZn0.9-xPO4:Mn0.1, Alx with the optimal x is 3.98 times of that of sample with x=0. The fact suggests that the Al3+ ions can enhance the emission of Mn2+. Furthermore, Al3+ doping only affects the intensity of Mn2+ emission, and cannot influence its mode. The value for chromaticity coordinate of Li0.97Zn0.87 PO4:Mn0.1, Al0.03 indicates that it is a green-yellow emitting phosphor, which can be potentially useful as a UV excited phosphor for LEDs.
  • Geochemical characteristics of black shale of the lower Cambrian in lower Yangtze area
    ZHU Qingjie, HOU Pengfei, YANG Shuaishuai, GUO Haiying, MA Lei, ZHANG Tao, REN Rui
    Science & Technology Review. 2015, 33(13): 17-21. https://doi.org/10.3981/j.issn.1000-7857.2015.13.002
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    The geologic characteristics and their hydrocarbon implication of black shale of the lower Cambrian in lower Yangtze area are analyzed by outcrop observation, sampling and geochemical analysis. The following conclusions are drawn. The black shale of lower Cambrian in lower Yangtze area has great thickness between 100 to 400 meters, and is mainly distributed in Shitai, Jingxian, Ningguo, Quanjiao, Gaoyou and Haian. It has high content of quartz in the mineral composition in this set of black shale, which is good for fracturing. The content of organic carbon ranges from 1% to 4% in lower Yangtze area, and is greater than 2.0% at depositional thickness center. The analysis of microscopic organic composition, carbon isotope of kerogen, Pr/Ph and saturated HC/ aromatic HC indicate that the kerogen type is Ⅰ. The origin of parent materials is aquatic organisms with high potential for hydrocarbon generation. The vitrinite reflectance is in the range of 2.0%~4.0%, in the stage of maturity to over-maturity. The black shale of lower Cambrian in lower Yangtze area has great thickness, high content of organic carbon, good kerogen type and high thermal maturity, which suggests promising exploration prospects.
  • Comprehensive utilization of waste heat from thermal discharge based on ecological engineering theory
    LIU Yongye, LIU Senlin, CHEN Xiaoqiu
    Science & Technology Review. 2015, 33(13): 22-26. https://doi.org/10.3981/j.issn.1000-7857.2015.13.003
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    The nuclear power plants oftoday have a thermal efficiency of about 33%, so the balance of this energy must be discharged to the environment, and therefore the management of this waste heat to provide the minimum impairment to environmental quality is of great importance.With the rapid development of China's nuclear power industry,the negative thermal effect (i.e. thermal pollution) of waste heat emissions of thermal discharge from nuclear power plants has drawn increasing attention of the public.The best way to solve this problem is the beneficial use of waste heat. This paper investigates the comprehensive utilization of waste heatin the background that the approach to waste heat utilization is single and inefficient.The concept of eco-design, relevant principles and integration of waste heat utilization projects and eco-design are elaborated. It is concluded that the final form of eco-design of waste heat utilization is“Venous Industry Based Eco-industrial Parks”, with the utilization of waste heat from thermal discharge as the main objective, and“Sector-specific Eco-industrial Parks”, with the nuclear power plant and the“optimal utilization approach”as the core and foundation.According to the environmental characteristics, environmental planning, industry status and development planning of a typical nuclear power plant in northern China, the "Seawater Desalination (RO, reverse osmosis membrane)" was selected as the "optimal utilization approach", and combined with the concept of eco-design, the conceptual design of waste heat utilization scheme was completed, and the energy saving potentialwas estimated for the typical site (the first phase of the project) when takingfull advantage of thermal discharge waste heat.
  • Stability analysis of pillar in undersea mining based on creep-damage coupling
    LIU Zhixiang, XIAO Siyou, LAN Ming, TANG Zhixiang
    Science & Technology Review. 2015, 33(13): 27-33. https://doi.org/10.3981/j.issn.1000-7857.2015.13.004
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Reservation pillar can control the deformation and the movement of the rock strata in seabed metal mining. But the deformation of pillar is greatly influenced by stress distribution and mining time. Maintaining the stability of pillar under long-term stress and seepage action is directly related to the safety of seabed mining. In order to study the stability of under-sea point pillar stope under long-term stress and seepage action, a new nonlinear creep constitutive model and a damage evolution equation are proposed based on statistical damage theory and Nishihara model. Meanwhile, a judgment method for transition from primary creep to accelerated creep stages is suggested. ANASYS is used to calculate the stress distribution of the stope. On this basis, the model is then applied to analysis of the viscosity-elastic-plastic damage and seepage property of an under-sea point pillar in Xinli district of Sanshandao gold mine. The result shows that the structure of the stope is stable. In the coming design of mine stopping, the number of pillars can be appropriately decreased so that the loss rate of ore will be reduced. The model gives enough thought to the mechanics paramater of rock mass as well as the result of engineering geological survey, so that it can be extended to other rheology models. It is also adapative to other large-scale rock engineering and has a rather high application value.
  • Component model establishment for polymer aging degradation and its application
    LU Xiang'an, JIANG Hanqiao, LI Junjian, FANG Wenchao, ZHAO Lin, PEI Yanli
    Science & Technology Review. 2015, 33(13): 34-38. https://doi.org/10.3981/j.issn.1000-7857.2015.13.005
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Aging degradation refers to the reduction of intrinsic viscosity and apparent viscosity, but the essence of this phenomenon is the breakage of large polymer molecules. During degradation, the distribution of polymer molecular weight changes, but its total mass concentration remains unchanged. If the polymer solution is made up of several pure components with different molecular weights, then a multi-component model can be used to describe the process of polymer degradation. Based on this idea, a twocomponent model of polymer degradation is established. In this model, polymer degradation occurs between two-components, large molecule component and small molecule component. Intrinsic viscosity and degradation coefficient of the latter component are obtained from laboratory experiment. These two parameters are used in the two-component model to describe the change of intrinsic viscosity during degradation. Furthermore, apparent viscosity change is obtained using semi-empirical relationship between intrinsic viscosity and apparent viscosity. Compared with the multi-component model, the two-component model not only reflects the polymer degradation mechanism but also the two parameters required are easier to obtain.
  • Study on demulsification and dehydration of emulsion of returned acidizing fluids and crude oil
    WAN Liping, KONG Bin, ZHU Li, MENG Yingfeng, ZHOU Bonian, ZHAI Lituan
    Science & Technology Review. 2015, 33(13): 39-45. https://doi.org/10.3981/j.issn.1000-7857.2015.13.006
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    The emulsion that is mixed with returned acidizing fluids and crude oil has strong stability, which may have a great influence on the crude oil dehydration and the safe operation of crude setting tank. The effects of temperature, demulsifier dosage, pH value, viscosity reducer dosage on the viscosity of emulsion and demulsification performance are studied, and the microscopic changes of emulsion at different times are observed. It is indicated by experiments that the viscosity of emulsion mixed with returned acidizing fluids and crude oil declines significantly firstly and then decreases gradually with the increasing temperature; when the temperature is lower than 40℃, the emulsion has stronger stability, however, between the temperature of 50-60℃, the dehydration rate does not increase significantly with the increasing temperature. So it is concluded that the best demulsification temperature is 50℃. It is also found that emulsion viscosity could be decreased by adding demulsifier, but not significantly; the more the dosage of demulsifier is, the better the demulsification performance is, and the dehydration rate is not remarkably increased when the demulsifier dosage is more than 150 mg/L. So it is concluded that the best demulsifier dosage is 150 mg/L. Moreover, it is beneficial for demulsification performance to adjust the returned acidizing fluids pH value to 6.0-7.0. With the increasing pH value, the oil water interface grows suddenly angular and the structure of crude oil after dewatering is more tight. Finally, the dehydrating speed is improved obviously by using viscosity reducer. These conclusions can be used as references to the demulsification and dehydration of emulsion that is flowed back early after the implementation of acidification.
  • An evaluation method of evaluate fracturing efficiency for tight gas well considering slippage
    DOU Xiangji, LIAO Xinwei, ZHAO Xiaoliang, CHEN Zhiming, ZHU Langtao
    Science & Technology Review. 2015, 33(13): 46-51. https://doi.org/10.3981/j.issn.1000-7857.2015.13.007
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    This paper proposes a new fracture half-length and slippage factor determination method for fractured wells in tight gas reservoirs. The tight gas reservoir is mainly developed with hydraulic fracturing. The traditional fracture half-length determination method based on production data analysis may lead to error in some tight gas wells due to ignoring the pressure-dependent gas properties and the existence of gas slippage. Besides, quick and accurate determination of slippage factor is also a problem that remains to be solved. To fulfill this target, relevant equations are modified based on linear flow analysis by introducing new pseudoparameters so as to take the pressure-dependent properties and slippage flow into consideration. By combining the idea of iteration, a new procedure used to evaluate the fracturing efficiency as well as determine the slippage factor is proposed and validated by both synthetic and filed examples. The validation procedure shows that this method is convenient and accurate in fracture efficiency evaluation. Therefore, this method could provide reference for dynamic retrieval of tight sandstone gas reservoir struggling with slippage phenomenon.
  • Optimization of integral fracturing design for horizontal well pattern arrangement in tight gas reservoir
    BIAN Xiaobing, ZHANG Jingchen, LI Shuangming, GUO Tiankui, ZHANG Shicheng
    Science & Technology Review. 2015, 33(13): 52-55. https://doi.org/10.3981/j.issn.1000-7857.2015.13.008
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Depletion development is the main method to exploit tight gas reservoir, and well interference is the unavoidable factor in well network deployment. According to the target area, a new integral fracturing well pattern arrangement model for horizontal wells in tight gas reservoir was set up based on the non-overlapping pressure sweep ellipse areas of all fractured horizontal wells. Firstly, by solving the major semi-axis and minor semi-axis of the equivalent ellipses by commercial reservoir simulator, the move among the target area and equivalent ellipses was simulated from the view of elastic potential energy, and the well pattern arrangement model could be resolved as acquiring the minimum potential-energy function, which was solved by quasi-physical algorithm owing to the high solving efficiency. The method was applied in M block, which is a rectangle tight gas reservoir with an average porosity of 7.2% and an average permeability of 0.43×10-3 μm2. Economic evaluation demonstrated that less fractured horizontal wells could achieve more net benefit when the gas price is low, while more fractured horizontal wells should be developed when the gas price is high.
  • Anti-fatigue effects of Panax ginseng oligopeptide of Jilin Province
    BAO Lei, WANG Junbo, CAI Xiaxia, ZHANG Yuan, SUN Bin, ZHANG Zhaofeng, LI Yong
    Science & Technology Review. 2015, 33(13): 56-60. https://doi.org/10.3981/j.issn.1000-7857.2015.13.009
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    The present study investigated the anti-fatigue effects of Panax ginseng oligopeptide of Jilin. 336 male ICR mice of SPF were randomized divided into 7 groups: control group, whey protein group, and other five groups of panax ginseng oligopeptide of Jilin at doses of 0.125, 0.250, 0.500, 1.000, 2.000 g/kg, respectively. After being fed for 30 days, the loading swimming time was determined by swimming experiment. The content of blood urea nitrogen and the activity of lactic dehydrogenase were measured by an automatic biochemical analyzer. The level of blood lacticacid in mouce was detected by ultraviolet spectrophotometer, and the liver glycogen of mouce was measured according to the kit. There were no significant differences between the control group and whey protein group in terms of the above indicators. Compared with the whey protein group, Panax ginseng oligopeptide of Jilin could significantly increase the burden swimming time, decrease the content of blood urea nitrogen and lactic acid, improve the activity of lactic dehydrogenase and increase the content of liver glycogen in mouce. Thus, it is concluded that panax ginseng oligopeptide of Jilin has excellent anti-fatigue effects in mouce.
  • Rice processing methods of Mylabris and their quality evaluation
    DONG Lei, XIE Lina, LI Chaoying, CHE Yi, SONG Dandan
    Science & Technology Review. 2015, 33(13): 61-65. https://doi.org/10.3981/j.issn.1000-7857.2015.13.010
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    This paper compares different rice processing methods of Mylabris, revealing the effect of rice processing in Mylabris preparation, and establishes a scientific and reasonable quality evaluation standard for Mylabris products. Three processing methods including rice paste stir-frying, rice stir-frying, and rice water method were compared and the quality of Mylabris products was evaluated in terms of appearance, smell and texture, clarity, excipient appearance and cantharidin content. We found that the Mylabris products processed using rice stir-frying had a full and oily appearance with no fluffy gray chips, a specific smell, and crispy texture, which are easy to grind into powder with slightly oily texture. The used rice was yellowish-brown with irregular crack and Mylabris chips on its surface. The cantharidin content in the raw product was 0.503%, which decreased in the processed Mylabris products using the three methods, ranging from 0.017% to 0.397%. The three methods all have scientific significance, with rice paste stirfrying being the optimum method, which guarantees the safety, effect, and quality control of the Mylabris products.
  • Application of wheat corner stone parents and innovation of germplasm resource in Sichuan Province
    LI Bangfa
    Science & Technology Review. 2015, 33(13): 66-70. https://doi.org/10.3981/j.issn.1000-7857.2015.13.011
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    The corner stone parents of 170 registered (recognized) wheat cultivars are analyzed in this paper. It is shown that the corner stone parents of the 58 registered cultivars and the 9 recognized cultivars before year of 2000 belong to Fan 6 and Mianyang No.11 series, respectively; 33 registered cultivars belong to Fan 6 and its total coefficient parentage is 9.25, which accounts for 49.28%; 21 registered cultivars belong to Mianyang No.11 series and the total coefficient parentage is 8.45, which accounts for 31.35%. Years 2001—2013 were a golden period of wheat breeding industry in Sichuan Province, with total 112 registered cultivars for new varieties of wheat, which overcame the weakness of using a single and narrow germplasm resource before 2000. More than 5 registered cultivars of the backbone parents were bred, including Mianyang 26, Guinong 21 and 92R system materials. They accounted for 10.7% , 9.8% , 6.3% of the 112 registered cultivars in this period. In addition, breeders created a batch of new germplasm resources: synthetic cultivar Chuanmai 42, SW system germplasm resources, R system germplasm resources, which started a new round of multiple backbone parent series.
  • Optimization design of a novel FBG anchor dynamometer with temperature self-compensation and its application
    SUI Qingmei, YE Qinglin, JIANG Shanchao, WANG Jing, CAO Yuqiang
    Science & Technology Review. 2015, 33(13): 71-75. https://doi.org/10.3981/j.issn.1000-7857.2015.13.012
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Because existing anchor end load testing instruments can not achieve long-term geotechnical engineering monitoring and long- distance data transmission, a novel FBG anchor dynamometer with simple mechanical structure and temperature selfcompensation suitable for engineering monitoring is proposed based on the axial strain characteristic of fiber Bragg grating. In order to improve strain transfer coefficient of this novel FBG sensor, its internal structure is analyzed by Solidworks 2012 finite element simulation software and further optimized based on axial strain distributions of this FBG anchor dynamometer. The relationship between center wavelength shift ΔλB of pressure sensitivity FBG and external load F is calculated to be ΔλB=9.4735·F theoretically. It is shown by performance experiment data that linearity of this sensor is larger than 0.99, its pressure measurement resolution is 0.093 kN and sensitivity coefficient K is 10.7 pm/kN. Coal mine tunnel pre-stressed anchor experiment data confirm that this sensor can achieve real-time surrounding rock pressure measurement, and that it well matches the measurement requirements under complex situation and has certain practical value.
  • Low-energy consumption tree routing security for wireless sensor networks
    QIN Danyang, JIA Shuang, WANG Erfu, DING Shuchun, ZHEN Jiaqi, ZHAO Bing
    Science & Technology Review. 2015, 33(13): 76-83. https://doi.org/10.3981/j.issn.1000-7857.2015.13.013
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Safe and reliable wireless sensor network (WSN) is an important branch of modern communication systems, and is an important technical support for ubiquitous communication. However, a large number of network attacks will threaten data security, which will seriously affect network reliability and greatly reduce the use value of WSN. This paper proposes a security model for lowenergy consumption tree routing protocols (LCTR), which achieves authentication and data integration using message authentication code (MAC) and digital signature (DS) techniques. Some common MACs and DSs have been taken as the reference to analyze the performance of LCTR. Simulating results show that with the model of LCTR, the safe transmitting rate of information is increased by 23% at most, and the network lifetime is increased by 5% at most.
    • Reviews
  • Progress on real-time monitoring technology in oil and gas industry based with fiber Bragg grating sensing
    SUN Yankun, LI Qi, LI Xiaying, YANG Duoxing
    Science & Technology Review. 2015, 33(13): 84-91. https://doi.org/10.3981/j.issn.1000-7857.2015.13.014
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    FBG (fiber Bragg grating) has been used to develop a kind of high precision and real-time monitoring technology, which possesses some unique advantages of high temperature and high pressure endurance, resistance to electromagnetic interference, ease of reuse and networking, etc. Obviously, it is bound to become the most promising monitoring method in oil and gas field, including carbon geological utilization and storage, acid gas injection, and earthquake net-working. In this paper, a development history and working principle of FBG are presented firstly, and the latest application status of FBG sensors in pipeline integrity monitoring, logging, seismic exploration is analyzed. Then, some key issues on real-time monitoring under complex environment conditions are discussed, and finally, development and application trends are put forward.
    • Focus
  • Industrialization of biochar from biomass pyrolysis:A new option for straw burning ban and green agriculture of China
    PAN Genxing, LI Lianqing, LIU Xiaoyu, CHENG Kun, BIAN Rongjun, JI Chunying, ZHENG Jufeng, ZHANG Xuhui, ZHENG Jinwei
    Science & Technology Review. 2015, 33(13): 92-101. https://doi.org/10.3981/j.issn.1000-7857.2015.13.015
    Abstract ( ) Download PDF ( ) HTML   Knowledge map   Save
    Treatment of crop straw has been an increasingly great challenge for China's agriculture and rural environment in the past decade. To break up institutional obstacles existing in straw treatment and burning ban, industrialized treatment for commercialized products has to be developed in line with market economy. Such industrialized treatment should focus on balanced utilization of energy and nutrients recycled in agriculture. In this review, biomass pyrolysis is introduced and its merits in straw treatment are discussed in detail. Addressing the properties and functions of biochar in soils and the agro-environment, we review the development of straw pyrolysis and biochar production, focusing on soil quality improvement and safe crop production in green agriculture. Industrialization of biomass pyrolysis and biochar production offers safe treatment of crop straw as well as new resources for agricultural production as biochar can be used to improve soil fertility, providing a green and innovative way for crop straw recycling. In the context of straw burning ban, the government is suggested to establish and improve subsidy policies for straw treatment, enhance supporting services for straw collection, and encourage the emerging industrial advantages of biomass pyrolysis to solve the problem of straw treatment through marketized development of green agriculture for developing sustainable agriculture in China.

Contact

  • Add：No. 86 Xueyuan South Road, Haidian District, Beijing　 Postal Code：100081
  • Tel: +86-10-62138113　Fax: +86-10-62138113
  • E-mail：kjdbbjb@cast.org.cn

    • Visited

      Total visitors:
      Visitors of today:
      Now online:
    Copyright © Science & Technology Review, All Rights Reserved.