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Rare Metals 2006年第2期25卷 129-137页

作者： SUN Jibing cui chunxiang ZHANG ying LI lin GAO Jianxia LIU Yuling School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China Postdoctoral Programme School of Information Engineering Hebei University of Technology Tianjin 300130 China

Sm2Fe17-xNbx （x = 0-4） powder was synthesized by HDDR treatment and nitrogenation. The effects of partial Nb substitution for Fe on the structural and magnetic properties of Sm2Fe17-xNbx alloys and their nitlides were investigated. It was seen that Sm2（Fe,Nb）17 phase exists in both annealed and HDDR-treated Sm2Fe17-xNbx alloys. However, its content is decreased with the increase in Nb substitution. In annealed alloys, Sm2（Fe,Nb）17 phase becomes unstable and will dissociate into SmFe2 and Fe-rich phases when x 〉 1.5. With HDDR-treatment, the Nb concentration in recombined Sm2（Fe,Nb）17 phase is decreased, and the content of Fe-rich phases is increased. Sm2Fe17-xNbx powder exhibits dendritic cracks and fine particles with a size of less than 300 nm. In nitrogenated alloys, N atoms mainly enter 2：17-type phase to form Sm2（Fe,Nb）17Ny. Partial Nb atoms in Sm2（Fe,Nb）17Ny phase will be released or excluded by nitrogen atoms. Fe-rich phases increase, and are followed by the amorphous Sm2（Fe,Nb）17Ny phase. Nb substitution for Fe with x = 0.5 and 1.0 in Sm2Fe17-xNbxNy powders increases the coercivity and remanence. But when x is greater than 2.0, Nb substitution will deteriorate the magnetic properties.

关键词： magnetic materials Sm-Fe-Nb-N alloys HDDR structural magnetic properties

Quantitative deconvolution of autocorrelations and cross correlations from two-dimensional lifetime decay maps in fluorescence lifetime correlation spectroscopy

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Science Bulletin 2017年第1期62卷 9-15页

作者： Shanshan Gao Menghua cui Ruiru Li Ling Liang ying Liu Liming Xie CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China University of Chinese Academy of Science Beijing 100049 China

Fluorescence correlation spectroscopy （FCS） is a widely used method for measuring molecular diffusion and chemical kinetics. However, when a mixture of fluorescent species is taken into account, the conven- tional FCS method has limitations in extracting autocorrelations for different species and cross correla- tions between different species. Recently developed fluorescence lifetime correlation spectroscopy （FLCS） based on time-tagged time-resolved （TITR） photon recording, which can record the global and micro arrival time for each individual photon, has been used to discriminate different species according to fluorescence lifetime. Here, based on two-dimensional lifetime decay maps constructed from TITR photon stream, we have developed a quantitative lifetime-deconvolution FCS model （LDFCS） to extract precise chemical rates for chemical conversions in multi-species systems. The key point of LDFCS model is separation of different species according to the global distribution of fluorescence lifetime and then deconvolution of autocorrelations and cross-correlations from the two-dimensional lifetime decay maps constructed bv the micro arrival times of photon pairs at each delay time.

关键词： Fluorescence lifetime Fluorescence correlation spectroscopy Cross correlation

Polybrominated diphenyl ethers in atmosphere and soil of a production area in China:Levels and partitioning

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Journal of Environmental Sciences 2011年第3期23卷 427-433页

作者： Jun Jin ying Wang Weizhi Liu Congqiao Yang Jicheng Hu Jian cui College of Life and Environmental Sciences Minzu University of China Beijing 100081 China Chinese Minority Tradition Medicine Center Minzu University of China Beijing 100081 China

Polybrominated diphenyl ethers （PBDEs） were measured in atmosphere and soil samples taken in winter and summer at a PBDE production area of Laizhou Bay in China. The concentrations of ∑11PBDE were 0.017-1.17 ng/m3 in gaseous phase, 0.5-161.1 ng/m3 in particulate phase, and 73-2629 ng/g dry weight in soil samples. The PBDE congener pattern in the gaseous phase differed from that in the particulate phase, and the PBDE congener pattern in the particulate phase was similar with that in soil. This demonstrated that there was little difference with atmospheric particle-soil transfer efficiency among PBDE congeners. In addition, there were seasonal variations in percentages on particle for lower brominated congeners. The BDE-28 was mostly in the gaseous phase in summer （88.3%）, whereas the average proportion of BDE-28 in gaseous phase in winter was 38.9%. Higher brominated congeners （i.e., BDE-206, BDE- 207, BDE-208, and BDE-209） were bound to the atmospheric particulate phase, and their potentials for long-range migration were mainly affected by the environmental behavior of atmospheric particles. Results indicated that PBDE congeners in summer were closer to gas-particle partition equilibrium than in winter. Temperature should be considered the main factor causing nonequilibrium in winter.

关键词： polybrominated diphenyl ethers atmosphere soil partitioning production area

Study on Unstable Characteristics of Centrifugal Pump under Different Cavitation Stages

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Journal of Thermal Science 2019年第4期28卷 608-620页

作者： DONG Liang SHANG Huanhuan ZHAO Yuqi LIU Houlin DAI cui WANG ying Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China

In order to reveal the regularity of unsteady flow of centrifugal pump under different cavitation stages,a visual closed test-bed is built to collect signals such as the distribution of cavitation bubbles at the impeller inlet and external characteristics,*** the process of cavitation of centrifugal *** with the shape and distribution of bubbles captured by high-speed photography,the cavitation stage of the centrifugal pump is *** addition,the variation of vorticity distribution,pressure pulsation and radial force of centrifugal pump under different cavitation stages are studied using the standard κ-ε turbulence model and the Kunz cavitation *** contributions are as follows:The cavitation bubbles can absorb the energy of vortex core to a certain extent and increase the volume of vortex *** bubbles can also block the flow-path and induce the distortion of the internal flow field,resulting in unstable pressure waves that cause a significant increase in pressure pulsation ***,with the development of cavitation,the radial force on the impeller tends to remain invariable first and then decrease,and trajectory of the radial force changes from closed to open.

关键词： centrifugal pump cavitation development stage cavitation bubble distribution pressure pulsation radial force

Generation and application of human iPS cells

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Chinese Science Bulletin 2009年第1期54卷 9-13页

作者： cui chun RAO LingJun CHENG LinZhao XIAO Lei Laboratory of Molecular Cell Biology Key Laboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology the Cell Bank/Stem Cell bank Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China Stem Cell Program Institute for Cell Engineering Johns Hopkins University School of Medicine Baltimore MD 21205 USA

Human embryonic stem (ES) cells are capable of unlimited proliferation and maintenance of pluripo-tency in vitro;these properties may lead to potential applications in regenerative medicine. However,immune rejection hampers the allogenic application of human ES cells. Over-expression of several specific transcription factors has been used to reprogram human adult cells into induced pluripotent stem (iPS) cells,which are similar to hESCs in many aspects. The iPS technique makes it possible to produce patient-specific pluripotent stem cells for transplantation therapy without immune rejection. However,some challenges remain,including viral vector integration into the genome,the existence of exogenous oncogenic factors,and low induction efficiency. Here,we review recent advances in human iPS methodology,as well as remaining challenges and its potential applications.

关键词：胚胎干细胞多能干细胞分化移植

Novel Synthesis of 2-Amino-3-ethoxycarbonyl Benzopyrans with Onium Salt as Soluble Support

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Chemical Research in Chinese Universities 2011年第3期27卷 435-440页

作者： ZHANG Li LU cui-fen YANG Gui-chun CHEN Zu-xing Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules. Faculty of Chemistry and Chemical Engineering Hubei University Wuhan 430062 P. R. China

Task specific onium salt has been presented as soluble support in the synthesis of benzopyrans in this paper. This method allows for results by far superior to those reported other soluble supports and allows for very... 详细信息

关键词： Onium salt Support Benzopyran

Loads and Dynamic Response Characteristic on FPSO Under Internal Solitary Waves

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China Ocean Engineering 2024年第5期38卷 785-796页

作者： ZHANG Rui-rui LI cui PU chun-rong LIU Qian YOU Yun-xiang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China China Resources(Nanjing)Municipal Design Co. Ltd.Nanjing 315100China State Key Laboratory of Ocean Engineering Shanghai Jiaotong UniversityShanghai 200240China

According to the established prediction model of internal solitary wave loads on FPSO in the previous work,the lumped mass model and the movement equations of finite displacement in time domain,the dynamic response model of interaction between internal solitary waves and FPSO with mooring lines were *** calculations and analysis,time histories of dynamic loads of FPSO exerted by internal solitary waves,FPSO’s motion and dynamic tension of mooring line were *** effects of the horizontal pretension of mooring line,the amplitude of internal solitary wave and layer fluid depth on dynamic response behavior of FPSO were *** was shown that the internal solitary waves had significant influence on FPSO,such as the large magnitude horizontal drift and a sudden tension *** internal solitary wave of −170 m amplitude in the ocean with upper and lower layer fluid depth ratio being 60:550,the dynamic loads reached 991.132 kN(horizontal force),18067.3 kN(vertical force)and−5042.92 kN·m(pitching moment).Maximum of FPSO’s horizontal drift was 117.56 *** increment of upstream mooring line approached 401.48 kN and that of backflow mooring line was−140 ***,the loads remained nearly constant with different pretension but increased obviously with the changing amplitude and layer fluid depth *** increments of mooring lines also changed little with the pretension but increased rapidly when amplitude and layer fluid depth ratio ***,FPSO’s motion increased quickly with not only the horizontal pretension but also the amplitude of internal solitary wave and layer fluid depth ratio.

关键词： internal solitary wave(ISW) dynamic response FPSO dynamic loads tension increment

A Holographic Diffraction Label Recognition Algorithm Based on Fusion Double Tensor Features

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Computer Systems Science & Engineering 2021年第9期38卷 291-303页

作者： Li Li Chen cui Jianfeng Lu Shanqing Zhang Ching-chun Chang Hangzhou Dianzi University Hangzhou310018China Zhejiang Police College Hangzhou310018China University of Warwick CoventryCV47ALUK

As an efficient technique for anti-counterfeiting,holographic diffraction labels has been widely applied to various *** to their unique feature,traditional image recognition algorithms are not ideal for the holographic diffraction label *** a tensor preserves the spatiotemporal features of an original sample in the process of feature extraction,in this paper we propose a new holographic diffraction label recognition algorithm that combines two tensor *** HSV(Hue Saturation Value)tensor and the HOG(Histogram of Oriented Gradient)tensor are used to represent the color information and gradient information of holographic diffraction label,***,the tensor decomposition is performed by high order singular value decomposition,and tensor decomposition matrices are *** into consideration of the different recognition capabilities of decomposition matrices,we design a decomposition matrix similarity fusion strategy using a typical correlation analysis algorithm and projection from similarity vectors of different decomposition matrices to the PCA(Principal Component Analysis)sub-space,then,the sub-space performs KNN(K-Nearest Neighbors)classification is *** effectiveness of our fusion strategy is verified by *** double tensor recognition algorithm complements the recognition capability of different tensors to produce better recognition performance for the holographic diffraction label system.

关键词： Label recognition holographic diffraction fusion double tensor matrix similarity

Fabrication and characterization of in situ AlN–TiN/Al composite ribbons

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Rare Metals 2015年第9期34卷 645-649页

作者： Kui Wang chun-Xiang cui Qian Wang Qing-Zhou Wang Hao Wang School of Materials Science and Engineering Hebei University of Technology Key Laboratory for New Type of Functional Materials Hebei University of Technology

The conventional wisdom is that the distribution and sizes of reinforcements, as well as the bonding strength of the matrix–reinforcement interface tend to be the crucial factors in determining the resulting properties of composites: the optimum mechanical properties are likely to be achieved when fine and thermally stable reinforcing particles are homogeneously distributed in a metal *** this study, in situ AlN–TiN/Al composite ribbons were successfully synthesized through plasma jet and subsequent melt-spinning method. The distribution and sizes of the particles in the ribbon were systematically *** average grain sizes of AlN and TiN in the AlN–TiN/Al composite ribbon are determined to be 27.7 and 29.6 nm,respectively. Moreover, analysis by scanning electron microscopy(SEM) results reveal that, compared with the AlN–TiN/Al bulk composite, particles like AlN and TiN could be far more homogeneously distributed in the matrix of the ribbon counterpart. In addition, the reinforcing effect of in situ nanoparticles, including AlN and TiN, was discussed as well.

关键词： Melt-spinning Reinforcing effect Nanoparticles

Sonic Hedgehog signaling pathway in primary liver cancer cells

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Asian Pacific Journal of Tropical Medicine 2014年第9期7卷 735-738页

作者： Lian-Yi Guo Pei Liu ying Wen Wei cui ying Zhou First Hospital Affiliated to Chinese Medical University Shenyang

Objective:To investigate clinical significance of Sonic Hedgehog(SHH)signaling pathway molecular Shh,Smo and Gli2 in primary hepatocellular carcinoma(HCC)***:A total of 30 HCC tissue samples were *** expression of SHH signaling pathway molecules Shh,Smo and Gli2 in HCC tissues and para-carcinoma tissue were detected by using immimohistochemical *** and normal liver tissue specimens were observed as control to analyze the expression of SHH signaling pathway molecular Shh,Smo and Glil mRMA in HCC tissues and corresponding para—carcinoma tissues and its relationship with the onset of ***:There was no expression of Shh,Smo and Gli2 protein in normal liver tissue,while their positive rates were 63.3%,76.79%and 66.7%in HCC tissues,respectively,with a significantly higher expression level than that in the para-carcinoma tissue(P0.05);Shh and Smo protein was detected in part of cirrhosis with positive expression,but Gli2 protein was not observable in cirrhosis ***:In HCC tissues,the high expression level of SHH signaling pathway molecules signal peptide(Shh),membrane protein receiptor(Smo)and nuclear transcription molecular(Gli2)can be indicators of the onset of liver cancer.

关键词： HCC Sonic Hedgehog signaling pathway Expression