28 September 2017, Volume 35 Issue 18

    

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  On Xi Jinping's thoughts on S&T and innovation

  WANG Chunfa

  Science & Technology Review. 2017, 35(18): 13-19. https://doi.org/10.3981/j.issn.1000-7857.2017.18.001

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  Science and technology are the foundation of the country's prosperity, and the innovation is the soul of the nation's progress. Since the 18th CPC National Congress, with his deep historical insight, broad international horizons and profound strategic visions, President Xi Jinping delivered a series of important discourses on some major issues, such as the S&T innovation evolution, the S&T and industry reform, the international S&T cooperation, the S&T institution reform, the national defense S&T, and the S&T talent cultivation. These discourses are very instructive with important theoretical significance. This paper systematically reviews President Xi's important discourses on the S&T innovation, focusing on 10 prominent features, and briefly discusses their scientific connotations and practical significance.
Spescial Issues
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  Review on soft-bodied robots

  HOU Taogang, WANG Tianmiao, SU Haohong, CHANG Shuai, CHEN Lingkun, HAO Yufei, WEN Li

  Science & Technology Review. 2017, 35(18): 20-28. https://doi.org/10.3981/j.issn.1000-7857.2017.18.002

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  With the advancement of the materials science, the chemistry, and the control technology, substantial knowledge about the mollusks is gained, including the octopus, the worm, and the starfish, which helps the development of a new type of robots:the soft robots. This paper reviews the development of the soft robots in recent years, focusing on the potential challenges in the materials, the driving methods, and the fields of applications. With consideration of China's national condition, this paper discusses the future prospect of the soft robots.
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  Soft materials for artificial robot

  ZHANG Ming, ZHANG Yiyang, LIU Junliang

  Science & Technology Review. 2017, 35(18): 29-38. https://doi.org/10.3981/j.issn.1000-7857.2017.18.003

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  Generally, soft materials for design and manufacture of bionic robots include the soft driving and sensing materials, as the receptor and the effector, respectively. The development of novel soft materials with high performance is very important. This paper reviews the conception of soft materials for bionic robots and the research development of the soft driving materials and sensing materials, including many examples in this area. The challenges and the future trend of this research field are discussed.
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  Review on magnetic powered flexible micro-/nanomotor

  DENG Xinghong, ZHANG Anning, LI Tianlong, ZHANG Guangyu, LI Longqiu

  Science & Technology Review. 2017, 35(18): 39-43. https://doi.org/10.3981/j.issn.1000-7857.2017.18.004

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  Magnetic powered micro-/nanomotors can be used in a variety of fluids, such as water, blood plasma and tissue fluid, because they are not driven by fuels. It can be remotely actuated in living organisms by an external magnetic field, noninvasively. The motion control of magnetic micro-/nanomotors can be easily achieved by modulating the external magnetic field generated by electromagnet. With these inherent advantages, magnetic micro-/nanomotors find a wide range of potential applications for medical treatments such as the targeted drug delivery and the cell manipulation. Swimming devices in a low Reynolds number environment must overcome the high viscosity force to achieve propulsion. The Scallop theorem requires that the flexible micro-/nanomotors must deform in a way which is not invariant in a time-reversal process. By these principles, three types of magnetic powered micro-/nanomotors were developed, which are the surface walkers, the helical magnetic propellers and the flexible magnetic propellers. Natural microorganisms achieve propulsion with flexible flagella or rigid helical flagella to break the time-reversal process. Inspired by swimming of microorganisms, the magnetic powered flexible micro-/nanomotors achieve motion in a low Reynolds number environment by a cyclic deformation powered by an external magnetic field. This type of flexible micro-/nanomotors have a high propulsion efficiency thus require a low magnetic field intensity. Four topics concerning this type of micro-/nanomotor are elaborated in this paper, namely, the fabrication, the mode of locomotion, the propulsion performance and the motion control. At last the problems that remain to be solved and the development tendency of magnetic powered flexible micro-/nanomotors are discussed.
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  A review of the flexible driving mode of underwater software robot and its mechanism of bionic movement

  FU Kejie, CAO Xunuo, ZHANG Zhen, LIU Xianwei, LI Guorui, LIANG Yiming, LI Tiefeng

  Science & Technology Review. 2017, 35(18): 44-51. https://doi.org/10.3981/j.issn.1000-7857.2017.18.005

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  With the increase of the underwater operation requirements and the development of the soft robot technology, the underwater soft robot becomes one of the top choices in the underwater robots. The underwater soft robots with artificial muscles to realize the drive control and the bionic motion become a research hot spot. This paper introduces underwater soft robots in seven kinds of the existing drive modes, based on the artificial muscles. The underwater soft robots can have five bionic movement forms. At the end, the future applications of underwater robots in the underwater exploration are discussed.
Reviews
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  50 Year's progress since the pulsar discovery and the detection of gravitational waves

  ZHANG Chengmin, WANG Shuangqiang, SHANG Lunhua, YANG Yiyan

  Science & Technology Review. 2017, 35(18): 52-57. https://doi.org/10.3981/j.issn.1000-7857.2017.18.006

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  The observation and the theoretical study of the pulsar have made a great progress since the first pulsar was discovered in 1967, honored with two Nobel Prizes. It is an extremely large physical laboratory in the universe, which not only can test the general relativity, but also measure the predicted gravitational waves. In this paper, we review the history and the properties of pulsars, and analyze its applications in the gravitational wave detection and the pulsar navigation. The pulsar detection of the five-hundred-meter Aperture Spherical Radio Telescope (FAST) is discussed, at the end.
Articles
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  Distributed multiple antenna reader positioning system for fast moving objects

  CUI Yinghua

  Science & Technology Review. 2017, 35(18): 58-63. https://doi.org/10.3981/j.issn.1000-7857.2017.18.007

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  In recent years, the RFID is widely used in indoor positioning fields. The existing positioning systems using the RFID technology have some problems in the aspects of the location accuracy, the efficiency, the reliability, the cost and others. A distributed multiple antenna array reader positioning system can achieve a fast and accurate positioning according to the signal intensity and the phase difference detected by receiving antennas. The local identification code can simplify the identification process and achieve a high-speed identification of target tags and meet the requirements of the fast moving object positioning. Compared with the traditional positioning method, the proposed algorithm has prominent advantages in the positioning speed, the positioning accuracy and the anti-interference ability.
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  Characteristics of ultrasonic propagation in carbonate rock pore model

  ZHOU You, CHEN Qiao, CHENG Liang, CAO Hai'an, XIE Zhiguo, LIU Jingcheng

  Science & Technology Review. 2017, 35(18): 64-72. https://doi.org/10.3981/j.issn.1000-7857.2017.18.008

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  This paper studies the characteristics of ultrasonic propagation in a model of a small pillar of the pore-cave type carbonate rock of different size and shape and distribution and in ultrasonic multi frequency, using the numerical simulation method of two-dimensional ultrasound and physical model experiments, from the perspective of kinematics and dynamics. The results show that in the single pore-cave discontinuous distribution, the size change almost has no effect on the velocity but is correlated with the attenuation coefficient positively; in the case of the same size, with the increase of the test frequency, the velocity increases, with the attenuation coefficient and the frequency in an exponential increasing relation. The influence of the hole shape (round holes or square holes) is related with the porosity. The porosity of 9% is the critical value. When it is less than 9%, the effects can be neglected; when it is more than 9%, the influence of circular holes is greater than that of square holes on the attenuation coefficient. The influence of elliptical holes is related with the aspect ratio, when the aspect ratio is greater than 1, with the increase of the aspect ratio, the attenuation coefficient changes little, whereas the attenuation coefficient varies greatly when the aspect ratio is less than 1. With the increase of the concentration of the pore distribution, the wave velocity decreases linearly, and the attenuation coefficient increases linearly.
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  Assessment of disaster-inducing gale hazard for expressway transportation

  SONG Jianyang, LIU Yanxiang, TIAN Hua, GAO Jingjing, LI Wanyu

  Science & Technology Review. 2017, 35(18): 73-79. https://doi.org/10.3981/j.issn.1000-7857.2017.18.009

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  Based on the observations of the 10-minute mean wind speed during 2005 to 2014 and the hourly extreme wind speed during 2009 to 2014 in 2373 national meteorological stations, and with consideration of the grades of wind effects on the expressway transportation in the meteorological standard (QX/T111-2010), the frequency and the intensity of the disaster-inducing gale are selected as the evaluation indexes, and the hazard of the disaster-inducing factors is evaluated with the entropy weight method. The nationwide distribution of the disaster-inducing gale hazard for the expressway transportation is obtained, which illustrates that the highest risk areas are mainly located in the west-central Inner Mongolia, the north and west Tibetan plateau, and Alashan Passes, Daban City, Sanshili and Baili Wind areas of Xinjiang. The second high risk areas are mainly distributed in the middle and west Inner Mongolia, the western Gansu, the western and southern Qinghai, the east and north-central Xinjiang, the northwest of Northern Xinjiang and the coastal areas of the northeastern Shandong Peninsula, the southeastern Fujian, the southwestern Hainan. The disaster-inducing gale hazard is relatively low in other regions.
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  Adsorption characteristics of heavy metal ions from aqueous solution by fermented stalk

  DONG Jing, SUN Changhong, WANG Yonggang, WANG Jianlong

  Science & Technology Review. 2017, 35(18): 80-85. https://doi.org/10.3981/j.issn.1000-7857.2017.18.010

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  The biosorption is a new technology, which can be widely applied for the removal of heavy metals from wastewater. The development of an efficient and low-cost adsorbent is a key in the biosorption technology. The adsorption performance of Pb(Ⅱ) by the fermented sweet sorghum stalks (FSSR) is discussed in this paper. The adsorption process is a chemical one and follows the pseudo-second order kinetics. After fermented, the equilibrium adsorption capacity of the material is increased from 3.32 mg/g to 6.92 mg/g. The isotherm adsorption is fitted well with the linear Langmuir model. When the temperature rises from 10℃ to 40℃, the maximum adsorption capacity of Pb (Ⅱ) is increased from 5.92 mg/g to 7.23 mg/g. In binary and ternary systems, the adsorption capacities are in the order of Pb(Ⅱ) > Cu (Ⅱ) > Zn(Ⅱ). There are more active functional groups on the surface of the stalk after fermentation, and these changes will be beneficial to the adsorption reaction and can improve the adsorption capacity.
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  Characteristics of photosynthesis and grain-filling of various winter wheat cultivars under extremely-late sown and water-saving cultivation conditions

  WANG Bin, ZHANG Meng, CHEN Jingtian, ZHANG Yinghua, HUANG Qin, WANG Zhimin

  Science & Technology Review. 2017, 35(18): 86-91. https://doi.org/10.3981/j.issn.1000-7857.2017.18.011

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  To select a suitable winter wheat cultivar under extremely-late sown and limited irrigation conditions in the heilonggang region, a 3 year field experiment is conducted using three cultivars varying in spike types:the large spike cultivar Weimai 8, the small spike cultivar Hengshui4399, and the medium spike cultivar Jimai 22. Characteristics of photosynthesis post-anthesis and dynamic of grainfilling are investigated for these extremely-late sown wheat cultivars. Results show that the yield differences among the cultivars are mainly due to the differences in the 1000 grain weight (TGW), with the Jimai 22 having the highest TGW and yield. Comparing with the Weimai 8 and the Hengshui 4399, the higher TGW of the Jimai 22 comes largely from the longer grain-filling period, especially, the active grainfilling period, and the higher grain-filling rate in the late grain-filling stages, closely associated with the higher light interception rate and photosynthetic rate. Thus, the medium spike cultivar Jimia 22 is a suitable cultivar under extremely-late sown and limited irrigation conditions in the heilonggang region.