• Title/Summary/Keyword: Shanghai

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Mesocarbon microbead densified matrix graphite A3-3 for fuel elements in molten salt reactors

  • Wang, Haoran;Xu, Liujun;Zhong, Yajuan;Li, Xiaoyun;Tang, Hui;Zhang, Feng;Yang, Xu;Lin, Jun;Zhu, Zhiyong;You, Yan;Lu, Junqiang;Zhu, Libing
    • Nuclear Engineering and Technology
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    • v.53 no.5
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    • pp.1569-1579
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    • 2021
  • This study aims to provide microstructural characterization for the matrix graphite which molten salt reactors (MSRs) use, and improve resistance to molten salt infiltration of the matrix graphite for fuel elements. Mesocarbon microbeads (MCMB) densified matrix graphite A3-3 (MDG) was prepared by a quasi-isostatic pressure process. After densification by MCMBs with average particle sizes of 2, 10, and 16 ㎛, the pore diameter of A3-3 decreased from 924 nm to 484 nm, 532 nm, and 778 nm, respectively. Through scanning electron microscopy, the cross-section energy spectrum and time-of-flight secondary ion mass spectrometry, resistance levels of the matrix graphite to molten salt infiltration were analyzed. The results demonstrate that adding a certain proportion of MCMB powders can improve the anti-infiltration ability of A3-3. Meanwhile, the closer the particle size of MCMB is to the pore diameter of A3-3, the smaller the average pore diameter of MDG and the greater the densification. As a matrix graphite of fuel elements in MSR was involved, the thermal and mechanical properties of matrix graphite MDG were also studied. When densified by the MCMB matrix graphite, MDGs can meet the molten salt anti-infiltration requirements for MSR operation.

Rapid Detection of SdhBP225F and SdhBH272R Mutations in Boscalid Resistant Botrytis cinerea Strains by ARMS-PCR

  • Liu, Xin;Zeng, Rong;Gao, Shigang;Xu, Lihui;Dai, Fuming
    • The Plant Pathology Journal
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    • v.35 no.1
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    • pp.71-76
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    • 2019
  • $SdhB^{P225F}$ and $SdhB^{H272R}$ mutations have been found associated with boscalid resistance in Botrytis cinerea from strawberry in Shanghai, China. For rapid detection of two mutations, tetra-primers were designed and optimized to gain the relatively high accuracy and specificity based on the ARMS-PCR technique, by which resistance can be identified with different lengths of products on agarose gels. The tetra-primer ARMS-PCR systems for $SdhB^{P225F}$ and $SdhB^{H272R}$ were validated by 9 SdhB-squenced strains repeatedly. Then, sensitivity of 30 more strains were also tested by the methods, which were accordant with genotypes by sequencing and the sensitivity of conidial germination to boscalid by 100%. Thus, the methods developed in this study are proved to be rapid, inexpensive, accurate and practical for resistance detection of Botrytis cinerea caused by $SdhB^{P225F}$ and $SdhB^{H272R}$ mutations.

Return Migration in Regional Innovation Systems

  • Sternberg, Rolf;Muller, Claudia
    • Journal of Technology Innovation
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    • v.13 no.2
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    • pp.71-95
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    • 2005
  • This study aims to explore and understand the role of return migrants in the regional innovation system of a transition economy (China) by analyzing the activities of returning entrepreneurs in two emerging high-tech industries in Shanghai. The empirical analysis is based on in-depth interviews with founders of high-tech companies and experts in Shanghai. The results of the analysis reveal that return migrants are a significant factor for the Shanghai innovation system, which is presently in a transition from a former manufacturing site to a metropolitan region comprising a range of industries (including high-tech) and services. First of all, return migrants are important for the Shanghai RIS in terms of numbers. Second, they engage in activities in the medium range of high-tech which reflects prevailing weaknesses of the framework conditions for innovation in Shanghai. However, due to their international background, returning entrepreneurs are able to overcome these weaknesses, and thus contribute to the development of high-tech industries in Shanghai and to a reduction of the technological lock-in.

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Study of the Key Technology of Ghost Imaging Based on Rosette Scanning

  • Zhang, Leihong;Kang, Yi;Pan, Zilan;Liang, Dong;Li, Bei;Zhang, Dawei;Ma, Xiuhua
    • Current Optics and Photonics
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    • v.1 no.5
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    • pp.491-499
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    • 2017
  • Ghost imaging offers great potential, with respect to standard imaging, for imaging objects in optically harsh or noisy environments. It can solve the problems that are difficult to solve by conventional imaging techniques. Recently, it has become a hot topic in quantum optics. In this paper, we propose a scheme for ghost imaging based on rosette scanning, named rosette ghost imaging. Sampling a small area sampling instead of the whole object, the instantaneous field of view of rosette scanning is used as the modulation light field in ghost imaging. This scheme reduces energy loss, the number of samples, and the sampling time, while improving the quality of the reconstructed image.

Gd effect on microstructure and properties of the Modified-690 alloy for function structure integrated thermal neutron shielding

  • Cheng Zhang;Jie Pan;Zixie Wang;Zhaoyu Wu;Qiliang Mei;Qianxue Ding;Jing Gao;Xueshan Xiao
    • Nuclear Engineering and Technology
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    • v.55 no.5
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    • pp.1541-1558
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    • 2023
  • The new Modified-690Gd alloy, namely as Ni-30Cr-(10-x) Fe-xGd (x = 0.5, 1.0, 1.5,2.0, 3.0 wt%) for function structure integrated thermal neutron shielding has been prepared and characterized. The Modified-690Gd alloy was mainly composed of γ austenite matrix and (Ni, Cr, Fe)5Gd precipitated along grain boundaries. The new Modified-690Gd alloy had great mechanical properties, which had the tensile strength exceeding 620 MPa and the elongation being above 50%. Meanwhile, this alloy had excellent weldability and good corrosion resistance in boric acid. The new Modified-690Gd alloy is expected to be a kind of high efficiency thermal neutron shielding materials.

The Study on the Development of Fast Railway Transportation Corridor Between Shanghai and Nanjing

  • Xu, Rui-Hua;Ji, Ling;Gong, Jia-Chong
    • Proceedings of the KOR-KST Conference
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    • 1996.06a
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    • pp.43-49
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    • 1996
  • In this paper, the south-north railway transportation demand and the present situation of Huning line(from Shanghai to Nanjing) are analyzed, and the important significance and the simulation, we also discuss the transportation organization plans, the transportation capacities, the stage by stage implement programs and the comprehensive social economic benefits on the condition of raising the train speed on Huning line.

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Chemical Constituents from Mussaenda Pubescens

  • Zhao, Weimin;Xu, Rensheng;Qin, Guowei;Tang, Xican;Li, Xiaoyu
    • Natural Product Sciences
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    • v.1 no.1
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    • pp.61-65
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    • 1995
  • A new triterpenoid saponin named Mussaendoside F(1), along with five known compounds (2-6) were isolated from aerial part of Mussaenda pubescens.

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