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Can Synthetic All-Metal Cluster Compound Support Multifold (n and a) Aromaticity and d-Orbital Aromaticity?

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Chinese Journal of Chemistry 2019年第2期37卷 126-130,I0002页

作者： Xue-rui you Hua-Jin Zhai Nanocluster Laboratory Institute of Molecular ScienceShanxi UniversityTaiyuanShanxi 030006China

Summary of main observation and conclusion There are active debates on whether the concept of aromaticity should be exte nded bey ond carb on based organic systems. One argument against such extension is that the proposed new aromatic species are not bottleable. We present herein in-depth chemical bonding analyses of a synthetic, core-shell, intermetalloid [Pd3Sn8Bi6]^4-.cluster. The computational data unravel unprecedented five-fold (π and σ) aromaticity, in cludi ng d-orbital aromaticity. Delocalized electr on clouds in this all-metal system cover the Pd3 core, trigonal pyramid Sn4 caps, peripheral Bi6 ring, and roof-like Sn2Bi2 walls, each following the (4n+2) Huckel rule. The present finding is beyond imagination, providing a compelling example that all-metal aromaticity not only exists in bulk compounds, but also can be in multifold π/σ fashion.

关键词： Synthetic All-Metal Cluster Support Multifold

Data-collection system for high-throughput X-ray absorption fine structure measurements

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Nuclear Science and Techniques 2016年第4期27卷 38-45页

作者： rui-you Lu Qian Gao Song-Qi Gu Ya-Yun Yang rui Si Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

A new X-ray absorption fine structure(XAFS)data-collection system based on the Experimental Physics and Industrial Control System software environment has been established at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility. The system provides for automatic sequential analysis of multiple samples for continuous high-throughput(HT) measurements. Specifically, 8 sample pellets are loaded into an alumina holder,and a high-precision two-dimensional translation stage is programmed to switch these samples automatically for collecting the XAFS spectrum of each sample in *** implement HT measurements via a graphical user interface developed with Control System ***, the successful operation of the HT XAFS system is demonstrated by running experiments on two groups of copper–ceria catalysts, each of which contains 8 different powder samples.

关键词： X射线吸收精细结构数据采集系统结构测量高通量上海同步辐射装置 XAFS谱测量与控制系统粉末样品

Mechanism of hydro-viscous soft start of belt conveyor

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Journal of China University of Mining and Technology 2008年第3期18卷 459-465页

作者： MENG Qing-rui HOU you-fu School of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The mechanism of a hydro-viscous soft start is of great importance in the design of a hydro-viscous clutch and its control system. To explain the mechanism of a hydro-viscous soft start, the startup process of a belt conveyor was numerically analyzed with the modified Reynolds equation, an energy equation and a temperature-viscosity equation. The effect of temperature and grooves of the friction disk surface on torque transfer and load capacity of the oil film have also been analyzed. The results show that 1) the grooves are the basis of forming dynamic pressure but they may reduce the capacity of torque transfer to a certain extent, 2) during the startup process, temperature has little effect on torque transfer and load capacity and the variation in load capacity of the oil film is very small, indicating that it is preferable to use the flow rate as a control object than the pressure of the feed cylinder. The results have been verified by an experiment.

关键词： hydro-viscous clutch soft start belt conveyor torque transfer load capacity

Research progress of electronic nose technology in exhaled breath disease analysis

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Microsystems & Nanoengineering 2023年第5期9卷 35-56页

作者： Ying Li Xiangyang Wei Yumeng Zhou Jing Wang rui you School of Instrument Science and Opto-Electronics Engineering Beijing Information Science and Technology UniversityBeijing 100192China Laboratory of Intelligent Microsystems Beijing Information Science and Technology UniversityBeijing 100192China School of Electronics and Information Engineering Changchun University of Science and TechnologyChangchun 130022China

Exhaled breath analysis has attracted considerable attention as a noninvasive and portable health diagnosis method due to numerous advantages,such as convenience,safety,simplicity,and avoidance of *** on many studies,exhaled breath analysis is a promising medical detection technology capable of diagnosing different diseases by analyzing the concentration,type and other characteristics of specific *** the existing gas analysis technology,the electronic nose(eNose)analysis method has great advantages of high sensitivity,rapid response,real-time monitoring,ease of use and ***,this review is intended to provide an overview of the application of human exhaled breath components in disease diagnosis,existing breath testing technologies and the development and research status of electronic nose *** the electronic nose technology section,the three aspects of sensors,algorithms and existing systems are summarized in ***,the related challenges and limitations involved in the abovementioned technologies are also ***,the conclusion and perspective of eNose technology are presented.

关键词： diagnosis analysis simplicity

Molecular Cloning and Bacterial Expression of Germacrene A Synthase cDNA from Crepidiastrum sonchifolium

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Chemical Research in Chinese Universities 2006年第5期22卷 606-611页

作者： REN Jie LIU Yan-qiu YANG Li NI rui you Song School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016 P. R. China

Germacrene A synthase（GAS） catalyzes the biosynthesis of germacrene A, which is a key precursor for sesquiterpone lactones. Cloning of a novel full-length cDNA encoding GAS from the medicinal plant Crepidiastrum sonchifolium（dosignated CsGAS） is reported in this study. The cDNA is 1837 bp long and contains a 1680-bp open reading frame encoding a 559 amino-acid protein. The functional expression of the cDNA in Escherichia coli, as an N-terminal thioredoxin fusion protein, with the pET32a vector yielding a recombinant enzyme. Sequence analysis was used to compare this enzyme with the mechanistically related epi-aristolochene synthase from tobacco, and the effect of possible involvement of a number of amino acids in sesquiterpone synthase on product specificity was also discussed.

关键词： Germacrene A synthase Crepidiastrum sonchifolium Sesquiterpene synthase Expression Fusion protein

Investigation of sorptive interactions between volatile organic compounds and supramolecules at dynamic oscillation using bulk acoustic wave resonator virtual sensor arrays

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Microsystems & Nanoengineering 2024年第4期10卷 175-184页

作者： Zilun Wang Zeyu Zhao Suhan Jin Feilong Bian Ye Chang Xuexin Duan Xiangdong Men rui you State Key Laboratory of NBC Protection for Civilian Beijing 102205China State Key Laboratory of Precision Measuring Technology&Instruments Tianjin UniversityTianjin 300072China School of Instrument Science and Opto-Electronics Engineering Beijing Information Science and Technology UniversityBeijing 100192China

Supramolecules are considered as promising materials for volatile organic compounds(VOCs)sensing *** proper understanding of the sorption process taking place in host-guest interactions is critical in improving the pattern recognition of supramolecules-based sensing ***,we report a novel approach to investigate the dynamic host-guest recognition process by employing a bulk acoustic wave(BAW)resonator capable of producing multiple oscillation amplitudes and simultaneously recording multiple responses to ***-assembled monolayers(SAMs)ofβ-cyclodextrin(β-CD)were modified on four BAW sensors to demonstrate the gas-surface interactions regarding oscillation amplitude and SAM *** on the method,a virtual sensor array(VSA)type electronic nose(e-nose)can be realized by pattern recognition of multiple responses at different oscillation amplitudes of a single *** analysis was realized respectively by using principal component analysis(PCA)for individual VOC identification and linear discriminant analysis(LDA)for VOCs mixtures classification.

关键词： oscillation volatile dynamic

Synthesis and Biological Evaluation of Novel 5,7-Diphenylimidazo[1,2-a]pyridine Derivatives

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Chemical Research in Chinese Universities 2014年第5期30卷 759-763页

作者： LIAO Huimin CHONG Lian'e TAN Li CHEN Xiaodan you rui GONG Ping Key Laboratory of Structure-Based Drug Design and Discovery Ministry of Education Shenyang Pharmaceutical University Shenyang 110016 P. R. China

A series of novel 5,7-diphenylimidazo[1,2-a]pyridine derivatives was designed and synthesized. The in vitro cytotoxic activities of all the target compounds against human colorectal cancer（HT-29）, human lung can- cer（H460）, human gastric cancer（MKN45） and human breast cancer（MDA-MB-231） cell lines were evaluated. The pharmacological results indicated that most of the target compounds showed moderate to excellent activities against the tested cell lines. The most promising compound 4h（0.20, 0.006, 0.08, 0.021 μmol/L） was 2.6, 5.1, 3.6 and 21.9 times more active than EPC2407（0.52, 0.031, 0.29, 0.46 μmol/L） against HT-29, H460, MKN45 and MDA-MB-231 cell lines, respectively.

关键词： Imidazo[1,2-a]pyridine Biological evaluation Antitumor activity

Soller slits automatic focusing method for multi-element fluorescence detector

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Nuclear Science and Techniques 2016年第5期27卷 179-187页

作者： Ya-Yun Yang Qian Gao Song-Qi Gu Hai-Sheng Yu rui-you Lu Yu-Ying Huang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

In X-ray absorption fine structure(XAFS) experiments,Soller slits are widely used as filter devices in order to improve the signal to noise *** high accuracy manual focusing operations is a time-consuming process;therefore,this work introduces an automatic focusing method for Soller slits in multi-element fluorescence *** method establishes a relation model between the fluorescence intensity distribution and the coordinates of the fluorescence excitation *** to this relation model,the actual coordinates of the fluorescence excitation point can be deduced from the detected fluorescence intensity distribution and used in focusing *** method has proven to be feasible in an XAFS experiment at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility.

关键词：荧光检测器聚焦方法狭缝 X射线吸收精细结构 XAFS实验关系模型光强度分布高信噪比

Stability of NiCrAlY coating/titanium alloy system under pure thermal exposure

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Rare Metals 2017年第8期36卷 659-665页

作者： Xiao-Min Peng An-Ru Wu Li-Jun Dong you-rui Tao Wei-Guo Gao Xiang-Lin Zhou State Key Laboratory of Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Hunan Institute of EngineeringXiangtan 411101China

In this paper,NiCrAlY coating was deposited on TC4 titanium alloy using arc ion plating,and the stability of NiCrAlY coating/TC4 substrate system under pure thermal exposure was analyzed in a wide temperature *** the thermal exposure,β→γ′→γphase transformation takes place in the NiCrAlY *** NiCrAlY coating phases totally decompose above the allotropic transformation temperature of *** allotropic transformation ofα-Ti to β-Ti of the substrate significantly influences the stability of NiCrAlY coating/TC4 substrate *** coating elements are mainly consumed by interfacial reactions below the allotropic transformation temperature of *** the allotropic transformation temperature of TC4,NiCrAlY coating elements are mainly consumed by element dissolution in β-*** NiCrAlY coating totally degrades for the dissolution of coating elements in the substrate to form thickβ-Ti stabilized layer.

关键词： NiCrAlY coating Titanium alloy Stability Pure thermal exposure Degradation