9 research outputs found

    人乳头瘤病毒18型病毒样颗粒在大肠杆菌中的表达及免疫原性分析

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    利用大肠杆菌表达系统可溶性表达人乳头瘤病毒18型(HPV18)L1蛋白,经过纯化和重组装过程获得HPV18病毒样颗粒(VLPs),研究其免疫原性和诱发中和抗体生成的水平。首先,提取HPV18的基因组DNA,通过PCR扩增获得HPV18 L1基因片段,将其插入pTrxFus表达载体,在大肠杆菌中可溶性表达HPV18 L1蛋白;其次,通过硫酸铵沉淀、离子交换层析和疏水相互作用层析获得高纯度的HPV18 L1蛋白,而后透析去除预先加入的还原剂DTT,使HPV18 L1蛋白自发组装成VLPs;最后,通过动态光散射技术和透射电子显微镜鉴定HPV18 VLPs的大小和形态,利用假病毒细胞中和实验评价HPV18 VLPs在实验动物体内的免疫原性和中和抗体生成水平。结果表明,HPV18L1蛋白可以在大肠杆菌表达系统中以可溶形式表达,经过纯化的HPV18 L1蛋白可以自发组装成为半径约为29.34nm、与HPV病毒外观相似的VLP。该VLPs在小鼠体内的中和抗体半数有效剂量为0.006μg,在兔及山羊体内诱导中和抗体滴度高达107。总之,本研究利用原核表达系统可简便高效地获得具有高度免疫原性的HPV18 VLPs,为HPV18预防性疫苗的开发奠定了基础,具有重要的应用意义

    General environment integrated monitoring and data management system based on virtual instrument

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    Conference Name:2nd International Conference of Electrical and Electronics Engineering, ICEEE 2011. Conference Address: Macau, China. Time:December 1, 2011 - December 2, 2011.International Industrial Electronics CenterFor the lack of integrated and advanced monitoring method and equipment, the existing general environment evaluation methods cannot entirely collect and analyze the monitoring parameters, which objectively reflect the condition of general environment, so an integrated monitoring and data management system for general environment based on virtual instrument technology is proposed in this paper. The monitoring and data management system which adopts a NI CompactDAQ data acquisition system functioning high speed real-time collection of multi-parameters of climate (temperature, wind speed, solar radiation), air quality (formaldehyde, benzene, radon, etc) soil and water quality, etc. Employing the LabVIEW programming tool, the software system was developed with friendly graphical user interface, which can display the real-time monitoring results of the multi-parameters mentioned above. Moreover, the LabSQL kit is used to access the database to search historical records of every parameter, summarize the trend of environment change and further objectively evaluate the condition of environment. This system can be used as parameter acquisition instrument for general environment, and provides a new way for evaluation of the general environment. 漏 2012 Springer-Verlag

    An environmental factors-based automatic control system for folding arm awning

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    Conference Name:2nd International Conference on Advances in Materials and Manufacturing Processes (ICAMMP 2011). Conference Address: Guilin, PEOPLES R CHINA. Time:DEC 16-18, 2011.This paper developed an automatic control system for folding arm awning based on environmental factors, which can overcome the disadvantages of the traditional awning of unitary control mode and low level of intelligence. The system consists of sensor unit, controller, drive motor and transmission mechanism. The sensor unit is used for testing light intensity, wind speed and rain, then an AT89S52 SCM single-chip microcomputer which is the core of the controller is applied to receive testing signal and send instructions to AC motor to realize the extending and withdrawing state of the awning according to the corresponding control logic. Meanwhile, this system is able to switch from automatic control to manual control so as to deal with power outage and other special situation and maintain operation of awning. The results of the prototype test show that this system is running steadily and can adjust the working condition of the awning in time according to the environment change. Compared with the current electric awning, the intelligent folding arm awning controlled according to environmental factors can achieve more energy conservation and environmental protection

    Research progress on techniques for artificial propagation of corals

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    在气候变化、环境污染以及人工采集等因素致使珊瑚野生资源不断衰退的背景下,开展珊瑚的人工繁育是修复珊瑚生态系统、保护生物多样性、减少野生珊瑚采集的主要出路之一.本文对国内外珊瑚人工繁育技术和研究进展进行综述,探讨了珊瑚有性和无性繁殖技术以及原地和异地繁育技术的特点与不足;重点从光照、水流、营养盐、微量元素、非自养珊瑚品种的饵料,以及适宜的微生物环境等方面总结了循环海水系统繁育珊瑚的研究进展,并对我国珊瑚研究现状进行了总结.光照是珊瑚水族箱养殖或异地繁殖的关键因素之一,不同种类的珊瑚对光照强度和色温有不同的需求,珊瑚照明创新技术的发展及其能耗对于珊瑚异地繁育非常重要.此外,珊瑚对铵氮、硝氮、亚硝氮及磷酸盐等营养盐的变化非常敏感,各类机械、化学和生物的技术被应用于降低培养体系中营养盐的含量.尽管珊瑚循环海水养殖系统在照明、水流和营养盐控制方面已经有了长足的进步,珊瑚人工繁育仍然任重道远.将来的突破方向在于有性繁殖、性状改造与疾病防治技术等方面.The natural coral reef resources degrade rapidly because of climate change,environmental pollution and exploitation of aquarium species.Artificial propagation is an effective way to facilitate the reduction of wild harvesting,reef restoration,preservation of biodiversity.This paper reviewed the technique and research progresses focused on coral artificial propagation.We compared the advantages and disadvantages of sexual reproduction and asexual reproduction as well as in situ and ex situ propagation.Moreover,we summarized the important roles of irradiation,flow rate,nutrients,feed and other factors in coral propagation within recirculating aquaculture system( RAS).Irradiation is the key to successful ex situ coral culture and different species show different needs of radiation intensity and light spectrum.Therefore,artificial lighting in RAS,as well as power and maintenance costs,are very important for ex situ coral aquaculture.In addition,corals are very sensitive to NH4+,NO3-,NO2-as well as phosphate in RAS,and many physical,chemical and biological methods are acquired to maintain low nutrients condition.Although RAS has progressed a lot in terms of irradiation,flow rate and nutrient control,future studies also should focus on sexual reproduction,genetic modification and disease control.国家海洋局公益性行业科研专项(201305027)资

    Solar powered automatic controlled advertising light box system

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    Conference Name:2011 International Conference on Mechanical Engineering, Materials and Energy, ICMEME 2011. Conference Address: Dalian, China. Time:October 19, 2011 - October 21, 2011.Trans Tech Publications Inc.; BOSI Education and Consultancy Co., LtdThis paper introduces a solar powered automatic controlled advertising light box system functioning box rotation and poster cycling displaying of each panel, which overcomes the disadvantages of ordinary advertising light boxes of humdrum displaying and high energy consumption. The system includes three parts which are box rotation system, poster scrolling system and single-axis sun tracking system which can improve the solar energy efficiency and reduce energy consumption. Sun tracking system which effectively combined the sun angle tracking and photoelectric tracking method can automatically switch between the work mode and hibernate mode according to time and weather condition so as to maximize energy efficiency. A hierarchical control strategy which contained main control system and sun tracking system is adopted to control light box rotation, panel displaying and sun tracking at the same time. The solar advertising light box system was verified by tests that with the hierarchical control strategy the power generated by solar panel increased 38.2% than fixed panel. Experiment results show that the light box works stably and has potential to apply under the situations where cable laying is not convenient. 漏 (2012) Trans Tech Publications, Switzerland

    The integrated testing system for performance parameters of the hydraulic excavator

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    Conference Name:3rd international Conference on Manufacturing Science and Engineering, ICMSE 2012. Conference Address: Xiamen, China. Time:March 27, 2012 - March 29, 2012.Fujian University of Technology; Xiamen University; Fuzhou University; Huaqiao University; University of WollongongThis paper designed and developed an integrated testing system for performance parameters of the Hydraulic excavator. Combined with sensing technology, computer technology and virtual instrument technology this system can detect six key parameters of the excavator including motor speed, hydraulic system pressure, attachment action time, swing speed, walking speed, current characteristics, so as to evaluate the performance of the excavator. The testing system takes full consideration of the interaction between the tester and driver, meanwhile, can automatically detect all parameters by using the parallel test method in order to make sure the whole test completed in one hour. As the testing system is designed base on the idea of modularization, it can add new modules to meet the functional requirements alone with the development of research in the future. This testing system can not only improve the test efficiency, but also be used as analysis tools for the research and optimization of performance parameters of excavators. 漏 (2012) Trans Tech Publications

    分辨率对DOAS测量二硫化碳影响的研究

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    差分光学吸收光谱技术(DOAS)由于易操作,耗费低,且具有高准确性和高分辨率等优点,非常适合对大气中难闻的有毒气体二硫化碳(CS2)进行实时监测。在DOAS测量过程中,分辨率的选择直接决定了CS2测量准确度。文章主要研究了分辨率对CS2被检测到的特征吸收结构形状的影响,以及CS2差分吸收截面随分辨率的变化趋势,从而确定了分辨率对CS2的最低可检测浓度的影响。通过研究分辨率与光强的关系,确定了分辨率与信噪比(S/N)的函数关系式,得出了DOAS测量CS2的最佳信噪比范围为0.41~0.50nm(FWHM)。在此范围既能够实现对CS2的准确定性定量分析(五种标样线性相关性r=0.999 9,测量10次的相对标准偏差小于0.3%),又能达到对CS2测量所需要的高灵敏度,高选择性和适用的时间分辨率同时保证了CS2具有区别于其他物质的特征吸收结构。最后对北京市丰台区的CS2进行了实时、连续地监测,取得了良好的效果

    在具有Cu衬底层的Si(111)面上自组装Co团簇的研究

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    Nanodots as low dimensional surface structures exhibit interesting physical properties which can be exploited in numerous applications such as a single electron transistor, optoelectronic- and magnetic storage-devices etc. Since the top-down techniques used currently are reaching their limits, the bottom-up self-assembly is probably the most promising technique for the growth of nanoscale systems due to the striving of a system toward a minimal energy and the formation of nanosized structures down to the atomic level. Nevertheless, controlling and tailoring the size and distribution of these nanodotes for possible devices is a challenge and requires a thorough knowledge of the complex interaction between atoms and surface. Since cobalt is regarded as one of the most important elements used in magnetic materials for magnetic or magneto-optical devices and silicon is the key element used in the semiconductor industry, the combination of these two materials will promote the development of materials and devices for next-century magnetoelectronics. However, it is known that Co reacts easily with Si even at room temperature [1]. Nevertheless, recent works have shown that a buffer layer still strongly affects the surface diffusion of deposited atoms and the subsequent island nucleation [2-5]. Annealing of monolayer (ML) amounts of Cu on Si(111) leads to an (5.55×5.55) periodic reconstruction with excellent thermal stability. Although the Cu/Si(111) layer does not exhibit a true long range periodicity, its good stability, together with the significant removal of the Si dangling bonds, indicates that it is a good template for the fabrication of self-assembled Co nanoclusters. As far as we know, there are few studies of Co/Cu/Si(111) system. The present study provides the structural property of self-assembled Co nanoclusters on Cu/Si(111) surface using scanning tunneling microscopy (STM). STM and LEED results show that the Co nanolusters changes not only in the island size but also in the island shape and structures on the top of the islands with increasing substrate temperature from room temperature to 830K during deposition. It was confirmed that the ultrathin buffer layer on Si (111) surface has a significant influence on the surface morphology after subsequent depostiong of Co. On one hand it can partly prevent Co to form Co silicide. On the other hand the diffusion of Co atoms on the surface can be greatly enhanced. [1] J. M. Phillips, J. L. Batstone, J. C. Hensel, I. Wu. M. Cerullo, J. Mater. Res. 5, 1032 (1990). [2] X. Liu, T. Iimori, K. Nakatsuji, and F. Komori, Appl. Phys. Lett. 88, 133102 (2006). [3] T. Schmidt, J. I. Flege, S. Gangopadhyay, T. Clausen, A. Locatelli, S. Heun, and J. Falta, Phys. Rev. Lett. 98, 066104 (2007) [4] P. Aivaliotis, L. R. Wilson, E. A. Zibik, J. W. Cockburn, M. J. Steer, and H. Y. Liu, Appl. Phys. Lett. 91, 013503 (2007). [5] Y. Takagi, A. Nishimura, A. Nagashima, and J. Yoshino, Surf. Sci. 514, 167 (2002). Keywords: STM, Si surface, Co silicide, nanoclusters
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